Use of Near-Infrared Spectroscopy and Chemometrics for the Nondestructive Identification of Concealed Damage in Raw Almonds (Prunus dulcis).

PubMed

Rogel-Castillo, Cristian; Boulton, Roger; Opastpongkarn, Arunwong; Huang, Guangwei; Mitchell, Alyson E

2016-07-27

Concealed damage (CD) is defined as a brown discoloration of the kernel interior (nutmeat) that appears only after moderate to high heat treatment (e.g., blanching, drying, roasting, etc.). Raw almonds with CD have no visible defects before heat treatment. Currently, there are no screening methods available for detecting CD in raw almonds. Herein, the feasibility of using near-infrared (NIR) spectroscopy between 1125 and 2153 nm for the detection of CD in almonds is demonstrated. Almond kernels with CD have less NIR absorbance in the region related with oil, protein, and carbohydrates. With the use of partial least squares discriminant analysis (PLS-DA) and selection of specific wavelengths, three classification models were developed. The calibration models have false-positive and false-negative error rates ranging between 12.4 and 16.1% and between 10.6 and 17.2%, respectively. The percent error rates ranged between 8.2 and 9.2%. Second-derivative preprocessing of the selected wavelength resulted in the most robust predictive model.

8 CFR 1101.2 - Presumption of lawful admission; entry under erroneous name or other errors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... the purpose of concealing his identity when obtaining a passport or visa, or for the purpose of using the passport or visa of another person or otherwise evading any provision of the immigration laws, and... time prior to making application for a passport or visa to have permitted the issuing authority or...

8 CFR 1101.2 - Presumption of lawful admission; entry under erroneous name or other errors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the purpose of concealing his identity when obtaining a passport or visa, or for the purpose of using the passport or visa of another person or otherwise evading any provision of the immigration laws, and... time prior to making application for a passport or visa to have permitted the issuing authority or...

8 CFR 1101.2 - Presumption of lawful admission; entry under erroneous name or other errors.

Code of Federal Regulations, 2012 CFR

2012-01-01

... the purpose of concealing his identity when obtaining a passport or visa, or for the purpose of using the passport or visa of another person or otherwise evading any provision of the immigration laws, and... time prior to making application for a passport or visa to have permitted the issuing authority or...

8 CFR 1101.2 - Presumption of lawful admission; entry under erroneous name or other errors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... the purpose of concealing his identity when obtaining a passport or visa, or for the purpose of using the passport or visa of another person or otherwise evading any provision of the immigration laws, and... time prior to making application for a passport or visa to have permitted the issuing authority or...

8 CFR 1101.2 - Presumption of lawful admission; entry under erroneous name or other errors.

Code of Federal Regulations, 2013 CFR

2013-01-01

... the purpose of concealing his identity when obtaining a passport or visa, or for the purpose of using the passport or visa of another person or otherwise evading any provision of the immigration laws, and... time prior to making application for a passport or visa to have permitted the issuing authority or...

Brain fingerprinting field studies comparing P300-MERMER and P300 brainwave responses in the detection of concealed information.

PubMed

Farwell, Lawrence A; Richardson, Drew C; Richardson, Graham M

2013-08-01

Brain fingerprinting detects concealed information stored in the brain by measuring brainwave responses. We compared P300 and P300-MERMER event-related brain potentials for error rate/accuracy and statistical confidence in four field/real-life studies. 76 tests detected presence or absence of information regarding (1) real-life events including felony crimes; (2) real crimes with substantial consequences (either a judicial outcome, i.e., evidence admitted in court, or a $100,000 reward for beating the test); (3) knowledge unique to FBI agents; and (4) knowledge unique to explosives (EOD/IED) experts. With both P300 and P300-MERMER, error rate was 0 %: determinations were 100 % accurate, no false negatives or false positives; also no indeterminates. Countermeasures had no effect. Median statistical confidence for determinations was 99.9 % with P300-MERMER and 99.6 % with P300. Brain fingerprinting methods and scientific standards for laboratory and field applications are discussed. Major differences in methods that produce different results are identified. Markedly different methods in other studies have produced over 10 times higher error rates and markedly lower statistical confidences than those of these, our previous studies, and independent replications. Data support the hypothesis that accuracy, reliability, and validity depend on following the brain fingerprinting scientific standards outlined herein.

Study and application of new Raman spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Qiushi; Zhang, Xiaohua

2016-03-01

Spatially Offset Raman Spectroscopy (SORS) is a new type of Raman Spectroscopy technology, which can detect the medium concealed in the opaque or sub-transparent material fast and nondestructively. The article summarized Spatially Offset Raman Spectroscopy`s international and domestic study and application progress on contraband detecting, medical science (bone ingredient, cancer diagnose etc.), agricultural products, historical relic identification etc. and stated the technology would become an effective measurement which had wide application prospect.

Impact of packet losses in scalable 3D holoscopic video coding

NASA Astrophysics Data System (ADS)

Conti, Caroline; Nunes, Paulo; Ducla Soares, Luís.

2014-05-01

Holoscopic imaging became a prospective glassless 3D technology to provide more natural 3D viewing experiences to the end user. Additionally, holoscopic systems also allow new post-production degrees of freedom, such as controlling the plane of focus or the viewing angle presented to the user. However, to successfully introduce this technology into the consumer market, a display scalable coding approach is essential to achieve backward compatibility with legacy 2D and 3D displays. Moreover, to effectively transmit 3D holoscopic content over error-prone networks, e.g., wireless networks or the Internet, error resilience techniques are required to mitigate the impact of data impairments in the user quality perception. Therefore, it is essential to deeply understand the impact of packet losses in terms of decoding video quality for the specific case of 3D holoscopic content, notably when a scalable approach is used. In this context, this paper studies the impact of packet losses when using a three-layer display scalable 3D holoscopic video coding architecture previously proposed, where each layer represents a different level of display scalability (i.e., L0 - 2D, L1 - stereo or multiview, and L2 - full 3D holoscopic). For this, a simple error concealment algorithm is used, which makes use of inter-layer redundancy between multiview and 3D holoscopic content and the inherent correlation of the 3D holoscopic content to estimate lost data. Furthermore, a study of the influence of 2D views generation parameters used in lower layers on the performance of the used error concealment algorithm is also presented.

Sub-component modeling for face image reconstruction in video communications

NASA Astrophysics Data System (ADS)

Shiell, Derek J.; Xiao, Jing; Katsaggelos, Aggelos K.

2008-08-01

Emerging communications trends point to streaming video as a new form of content delivery. These systems are implemented over wired systems, such as cable or ethernet, and wireless networks, cell phones, and portable game systems. These communications systems require sophisticated methods of compression and error-resilience encoding to enable communications across band-limited and noisy delivery channels. Additionally, the transmitted video data must be of high enough quality to ensure a satisfactory end-user experience. Traditionally, video compression makes use of temporal and spatial coherence to reduce the information required to represent an image. In many communications systems, the communications channel is characterized by a probabilistic model which describes the capacity or fidelity of the channel. The implication is that information is lost or distorted in the channel, and requires concealment on the receiving end. We demonstrate a generative model based transmission scheme to compress human face images in video, which has the advantages of a potentially higher compression ratio, while maintaining robustness to errors and data corruption. This is accomplished by training an offline face model and using the model to reconstruct face images on the receiving end. We propose a sub-component AAM modeling the appearance of sub-facial components individually, and show face reconstruction results under different types of video degradation using a weighted and non-weighted version of the sub-component AAM.

Component pattern analysis of chemicals using multispectral THz imaging system

NASA Astrophysics Data System (ADS)

Kawase, Kodo; Ogawa, Yuichi; Watanabe, Yuki

2004-04-01

We have developed a novel basic technology for terahertz (THz) imaging, which allows detection and identification of chemicals by introducing the component spatial pattern analysis. The spatial distributions of the chemicals were obtained from terahertz multispectral transillumination images, using absorption spectra previously measured with a widely tunable THz-wave parametric oscillator. Further we have applied this technique to the detection and identification of illicit drugs concealed in envelopes. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

Non-destructive terahertz imaging of illicit drugs using spectral fingerprints

NASA Astrophysics Data System (ADS)

Kawase, Kodo; Ogawa, Yuichi; Watanabe, Yuuki; Inoue, Hiroyuki

2003-10-01

The absence of non-destructive inspection techniques for illicit drugs hidden in mail envelopes has resulted in such drugs being smuggled across international borders freely. We have developed a novel basic technology for terahertz imaging, which allows detection and identification of drugs concealed in envelopes, by introducing the component spatial pattern analysis. The spatial distributions of the targets are obtained from terahertz multispectral transillumination images, using absorption spectra measured with a tunable terahertz-wave source. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

Testing a potential alternative to traditional identification procedures: Reaction time-based concealed information test does not work for lineups with cooperative witnesses.

PubMed

Sauerland, Melanie; Wolfs, Andrea C F; Crans, Samantha; Verschuere, Bruno

2017-11-27

Direct eyewitness identification is widely used, but prone to error. We tested the validity of indirect eyewitness identification decisions using the reaction time-based concealed information test (CIT) for assessing cooperative eyewitnesses' face memory as an alternative to traditional lineup procedures. In a series of five experiments, a total of 401 mock eyewitnesses watched one of 11 different stimulus events that depicted a breach of law. Eyewitness identifications in the CIT were derived from longer reaction times as compared to well-matched foil faces not encountered before. Across the five experiments, the weighted mean effect size d was 0.14 (95% CI 0.08-0.19). The reaction time-based CIT seems unsuited for testing cooperative eyewitnesses' memory for faces. The careful matching of the faces required for a fair lineup or the lack of intent to deceive may have hampered the diagnosticity of the reaction time-based CIT.

Prediction of transmission distortion for wireless video communication: analysis.

PubMed

Chen, Zhifeng; Wu, Dapeng

2012-03-01

Transmitting video over wireless is a challenging problem since video may be seriously distorted due to packet errors caused by wireless channels. The capability of predicting transmission distortion (i.e., video distortion caused by packet errors) can assist in designing video encoding and transmission schemes that achieve maximum video quality or minimum end-to-end video distortion. This paper is aimed at deriving formulas for predicting transmission distortion. The contribution of this paper is twofold. First, we identify the governing law that describes how the transmission distortion process evolves over time and analytically derive the transmission distortion formula as a closed-form function of video frame statistics, channel error statistics, and system parameters. Second, we identify, for the first time, two important properties of transmission distortion. The first property is that the clipping noise, which is produced by nonlinear clipping, causes decay of propagated error. The second property is that the correlation between motion-vector concealment error and propagated error is negative and has dominant impact on transmission distortion, compared with other correlations. Due to these two properties and elegant error/distortion decomposition, our formula provides not only more accurate prediction but also lower complexity than the existing methods.

Studies on image compression and image reconstruction

NASA Technical Reports Server (NTRS)

Sayood, Khalid; Nori, Sekhar; Araj, A.

1994-01-01

During this six month period our works concentrated on three, somewhat different areas. We looked at and developed a number of error concealment schemes for use in a variety of video coding environments. This work is described in an accompanying (draft) Masters thesis. In the thesis we describe application of this techniques to the MPEG video coding scheme. We felt that the unique frame ordering approach used in the MPEG scheme would be a challenge to any error concealment/error recovery technique. We continued with our work in the vector quantization area. We have also developed a new type of vector quantizer, which we call a scan predictive vector quantization. The scan predictive VQ was tested on data processed at Goddard to approximate Landsat 7 HRMSI resolution and compared favorably with existing VQ techniques. A paper describing this work is included. The third area is concerned more with reconstruction than compression. While there is a variety of efficient lossless image compression schemes, they all have a common property that they use past data to encode future data. This is done either via taking differences, context modeling, or by building dictionaries. When encoding large images, this common property becomes a common flaw. When the user wishes to decode just a portion of the image, the requirement that the past history be available forces the decoding of a significantly larger portion of the image than desired by the user. Even with intelligent partitioning of the image dataset, the number of pixels decoded may be four times the number of pixels requested. We have developed an adaptive scanning strategy which can be used with any lossless compression scheme and which lowers the additional number of pixels to be decoded to about 7 percent of the number of pixels requested! A paper describing these results is included.

Imaging terahertz radar for security applications

NASA Astrophysics Data System (ADS)

Semenov, Alexei; Richter, Heiko; Böttger, Ute; Hübers, Heinz-Wilhelm

2008-04-01

Detection of concealed threats is a key issue in public security. In short range applications, passive imagers operating at millimeter wavelengths fulfill this task. However, for larger distances, they will suffer from limited spatial resolution. We will describe the design and performance of 0.8-THz imaging radar that is capable to detect concealed objects at a distance of more than 20 meter. The radar highlights the target with the built-in cw transmitter and analyses the returned signal making use of a heterodyne receiver with a single superconducting hot-electron bolometric mixer. With an integration time of 0.3 sec, the receiver distinguishes a temperature difference of 2 K at the 20 m distance. Both the transmitter and the receiver use the same modified Gregorian telescope consisting from two offset elliptic mirrors. The primary mirror defines limits the lateral resolution of the radar to 2 cm at 20 m distance. At this distance, the field of view of the radar has the diameter 0.5 m. It is sampled with a high-speed conical scanner that allows for a frame time less than 5 sec. The transmitter delivers to the target power with a density less than ten microwatt per squared centimeter, which is harmless for human beings. The radar implements a sensor fusion technique that greatly improves the ability to identify concealed objects.

Deep Raman spectroscopy for the non-invasive standoff detection of concealed chemical threat agents.

PubMed

Izake, Emad L; Cletus, Biju; Olds, William; Sundarajoo, Shankaran; Fredericks, Peter M; Jaatinen, Esa

2012-05-30

Deep Raman spectroscopy has been utilized for the standoff detection of concealed chemical threat agents from a distance of 15 m under real life background illumination conditions. By using combined time and space resolved measurements, various explosive precursors hidden in opaque plastic containers were identified non-invasively. Our results confirm that combined time and space resolved Raman spectroscopy leads to higher selectivity towards the sub-layer over the surface layer as well as enhanced rejection of fluorescence from the container surface when compared to standoff spatially offset Raman spectroscopy. Raman spectra that have minimal interference from the packaging material and good signal-to-noise ratio were acquired within 5 s of measurement time. A new combined time and space resolved Raman spectrometer has been designed with nanosecond laser excitation and gated detection, making it of lower cost and complexity than picosecond-based laboratory systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Quantum Image Steganography and Steganalysis Based On LSQu-Blocks Image Information Concealing Algorithm

NASA Astrophysics Data System (ADS)

A. AL-Salhi, Yahya E.; Lu, Songfeng

2016-08-01

Quantum steganography can solve some problems that are considered inefficient in image information concealing. It researches on Quantum image information concealing to have been widely exploited in recent years. Quantum image information concealing can be categorized into quantum image digital blocking, quantum image stereography, anonymity and other branches. Least significant bit (LSB) information concealing plays vital roles in the classical world because many image information concealing algorithms are designed based on it. Firstly, based on the novel enhanced quantum representation (NEQR), image uniform blocks clustering around the concrete the least significant Qu-block (LSQB) information concealing algorithm for quantum image steganography is presented. Secondly, a clustering algorithm is proposed to optimize the concealment of important data. Finally, we used Con-Steg algorithm to conceal the clustered image blocks. Information concealing located on the Fourier domain of an image can achieve the security of image information, thus we further discuss the Fourier domain LSQu-block information concealing algorithm for quantum image based on Quantum Fourier Transforms. In our algorithms, the corresponding unitary Transformations are designed to realize the aim of concealing the secret information to the least significant Qu-block representing color of the quantum cover image. Finally, the procedures of extracting the secret information are illustrated. Quantum image LSQu-block image information concealing algorithm can be applied in many fields according to different needs.

Self-Concealment and Suicidal Behaviors

ERIC Educational Resources Information Center

Friedlander, Adam; Nazem, Sarra; Fiske, Amy; Nadorff, Michael R.; Smith, Merideth D.

2012-01-01

Understanding self-concealment, the tendency to actively conceal distressing personal information from others, may be important in developing effective ways to help individuals with suicidal ideation. No published study has yet assessed the relation between self-concealment and suicidal behaviors. Additionally, most self-concealment research has…

Spatial pattern separation of chemicals and frequency-independent components by terahertz spectroscopic imaging

NASA Astrophysics Data System (ADS)

Watanabe, Yuuki; Kawase, Kodo; Ikari, Tomofumi; Ito, Hiromasa; Ishikawa, Youichi; Minamide, Hiroaki

2003-10-01

We separated the component spatial patterns of frequency-dependent absorption in chemicals and frequency-independent components such as plastic, paper, and measurement noise in terahertz (THz) spectroscopic images, using known spectral curves. Our measurement system, which uses a widely tunable coherent THz-wave parametric oscillator source, can image at a specific frequency in the range 1-2 THz. The component patterns of chemicals can easily be extracted by use of the frequency-independent components. This method could be successfully used for nondestructive inspection for the detection of illegal drugs and devices of bioterrorism concealed, e.g., inside mail and packages.

Spatial autocorrelation among automated geocoding errors and its effects on testing for disease clustering

PubMed Central

Li, Jie; Fang, Xiangming

2010-01-01

Automated geocoding of patient addresses is an important data assimilation component of many spatial epidemiologic studies. Inevitably, the geocoding process results in positional errors. Positional errors incurred by automated geocoding tend to reduce the power of tests for disease clustering and otherwise affect spatial analytic methods. However, there are reasons to believe that the errors may often be positively spatially correlated and that this may mitigate their deleterious effects on spatial analyses. In this article, we demonstrate explicitly that the positional errors associated with automated geocoding of a dataset of more than 6000 addresses in Carroll County, Iowa are spatially autocorrelated. Furthermore, through two simulation studies of disease processes, including one in which the disease process is overlain upon the Carroll County addresses, we show that spatial autocorrelation among geocoding errors maintains the power of two tests for disease clustering at a level higher than that which would occur if the errors were independent. Implications of these results for cluster detection, privacy protection, and measurement-error modeling of geographic health data are discussed. PMID:20087879

The nest-concealment hypothesis: New insights from a comparative analysis

USGS Publications Warehouse

Borgmann, Kathi L.; Conway, Courtney J.

2015-01-01

Selection of a breeding site is critical for many animals, especially for birds whose offspring are stationary during development. Thus, birds are often assumed to prefer concealed nest sites. However, 74% of studies (n = 106) that have evaluated this relationship for open-cup nesting songbirds in North America failed to support the nest-concealment hypothesis. We conducted a comparative analysis to identify factors that contribute to variation in the ability of researchers to find support for the nest-concealment hypothesis. We found that some of the discrepancy among studies can be explained by interspecific differences in morphological and extrinsic factors that affect nest predation. Moreover, methods that investigators used to estimate concealment affected whether studies found support for the nest-concealment hypothesis; 33% of the studies that used quantitative estimates found support for the nest-concealment hypothesis whereas only 10% of the studies that used qualitative estimates found support. The timing of measurements also explained some of the ambiguity; studies that provided little information regarding the timing of their foliage density estimates were less likely to support the nest-concealment hypothesis. Species with more conspicuous male plumage were less likely to support the nest-concealment hypothesis when we analyzed studies that used visual estimates. Whereas species with more conspicuous female plumage were more likely to support the nest-concealment hypothesis when we analyzed studies that used quantitative measures. Our results demonstrate that support for the nest-concealment hypothesis has been equivocal, but that some of the ambiguity can be explained by morphological traits and methods used to measure concealment.

Relationship between concealment of emotions at work and musculoskeletal symptoms: results from the third Korean Working Conditions Survey.

PubMed

Jung, Kyungyong; Kim, Dae Hwan; Ryu, Ji Young

2018-05-11

In this study, we explored the relationship between concealing emotions at work and musculoskeletal symptoms in Korean workers using data from a national, population-based survey. Data were obtained from the third Korean Working Conditions Survey in 2011. We investigated the prevalence of three musculoskeletal symptoms ("back pain", "pain in the upper extremities", and "pain in the lower extremities"). Multiple logistic regression analysis was also performed to determine odds ratios (ORs) for musculoskeletal symptoms according to concealing emotions at work, adjusting for socioeconomic factors. In both sexes, the emotion-concealing group showed a significantly higher prevalence of "pain in the upper extremities" and "pain in the lower extremities" than the non-emotion-concealing group. For back pain, male - but not female - workers who concealed their emotions showed a higher prevalence than their non-emotion-concealing counterparts; the difference was statistically significant. Adjusted ORs for musculoskeletal symptoms (excluding "back pain" for female workers) in the emotion-concealing group were significantly higher. Our study suggests that concealment of emotions is closely associated with musculoskeletal symptoms, and the work environment should operate in consideration not only of the physical health work condition of workers but also of their emotional efforts including concealing emotion at work.

An Exploratory Investigation of Social Stigma and Concealment in Patients with Multiple Sclerosis.

PubMed

Cook, Jonathan E; Germano, Adriana L; Stadler, Gertraud

2016-01-01

We conducted a preliminary investigation into dimensions of stigma and their relation to disease concealment in a sample of American adults living with multiple sclerosis (MS). Fifty-three adults with MS in the United States completed an online survey assessing anticipated, internalized, and isolation stigma, as well as concealment. Responses to all the scales were relatively low, on average, but above scale minimums (P < .001). Ratings of isolation stigma and concealment were highest. Anticipated stigma strongly predicted concealment. Many adults living with MS may be concerned that they will be the target of social stigma because of their illness. These concerns are associated with disease concealment. More research is needed to investigate how MS stigma and concealment may be independent contributors to health in patients with MS.

Concealment of sexual orientation.

PubMed

Sylva, David; Rieger, Gerulf; Linsenmeier, Joan A W; Bailey, J Michael

2010-02-01

Sex-atypical behaviors may be used to identify a person as homosexual. To shield themselves from prejudice, homosexual people may attempt to conceal these behaviors. It is not clear how effectively they can do so. In Study 1, we asked homosexual participants to conceal their sex-atypical behaviors while talking about the weather. Raters watched videos of the participants and judged the likelihood that each participant was homosexual. Homosexual participants were able to partially conceal signs of their orientation, but they remained distinguishable from heterosexual participants. In Study 2, we tested the ability to conceal signs of one's sexual orientation in a more demanding situation: a mock job interview. In this scenario, homosexual men were even less effective at concealing their orientation. Higher cognitive demands in this new situation may have interfered with their ability to conceal.

A definitional framework for the human/biometric sensor interaction model

NASA Astrophysics Data System (ADS)

Elliott, Stephen J.; Kukula, Eric P.

2010-04-01

Existing definitions for biometric testing and evaluation do not fully explain errors in a biometric system. This paper provides a definitional framework for the Human Biometric-Sensor Interaction (HBSI) model. This paper proposes six new definitions based around two classifications of presentations, erroneous and correct. The new terms are: defective interaction (DI), concealed interaction (CI), false interaction (FI), failure to detect (FTD), failure to extract (FTX), and successfully acquired samples (SAS). As with all definitions, the new terms require a modification to the general biometric model developed by Mansfield and Wayman [1].

Local indicators of geocoding accuracy (LIGA): theory and application

PubMed Central

Jacquez, Geoffrey M; Rommel, Robert

2009-01-01

Background Although sources of positional error in geographic locations (e.g. geocoding error) used for describing and modeling spatial patterns are widely acknowledged, research on how such error impacts the statistical results has been limited. In this paper we explore techniques for quantifying the perturbability of spatial weights to different specifications of positional error. Results We find that a family of curves describes the relationship between perturbability and positional error, and use these curves to evaluate sensitivity of alternative spatial weight specifications to positional error both globally (when all locations are considered simultaneously) and locally (to identify those locations that would benefit most from increased geocoding accuracy). We evaluate the approach in simulation studies, and demonstrate it using a case-control study of bladder cancer in south-eastern Michigan. Conclusion Three results are significant. First, the shape of the probability distributions of positional error (e.g. circular, elliptical, cross) has little impact on the perturbability of spatial weights, which instead depends on the mean positional error. Second, our methodology allows researchers to evaluate the sensitivity of spatial statistics to positional accuracy for specific geographies. This has substantial practical implications since it makes possible routine sensitivity analysis of spatial statistics to positional error arising in geocoded street addresses, global positioning systems, LIDAR and other geographic data. Third, those locations with high perturbability (most sensitive to positional error) and high leverage (that contribute the most to the spatial weight being considered) will benefit the most from increased positional accuracy. These are rapidly identified using a new visualization tool we call the LIGA scatterplot. Herein lies a paradox for spatial analysis: For a given level of positional error increasing sample density to more accurately follow the underlying population distribution increases perturbability and introduces error into the spatial weights matrix. In some studies positional error may not impact the statistical results, and in others it might invalidate the results. We therefore must understand the relationships between positional accuracy and the perturbability of the spatial weights in order to have confidence in a study's results. PMID:19863795

Student attitudes toward concealed handguns on campus at 2 universities.

PubMed

Cavanaugh, Michael R; Bouffard, Jeffrey A; Wells, William; Nobles, Matt R

2012-12-01

We examined student support for a policy that would allow carrying of concealed handguns on university campuses. Large percentages of students at 2 universities expressed very low levels of comfort with the idea of permitting concealed handgun carrying on campus, suggesting that students may not welcome less restrictive policies. Students held slightly different opinions about concealed handguns on and off campus, suggesting that they view the campus environment as unique with respect to concealed handgun carrying.

Student Attitudes Toward Concealed Handguns on Campus at 2 Universities

PubMed Central

Bouffard, Jeffrey A.; Wells, William; Nobles, Matt R.

2012-01-01

We examined student support for a policy that would allow carrying of concealed handguns on university campuses. Large percentages of students at 2 universities expressed very low levels of comfort with the idea of permitting concealed handgun carrying on campus, suggesting that students may not welcome less restrictive policies. Students held slightly different opinions about concealed handguns on and off campus, suggesting that they view the campus environment as unique with respect to concealed handgun carrying. PMID:22720763

Spatiotemporal Filtering Using Principal Component Analysis and Karhunen-Loeve Expansion Approaches for Regional GPS Network Analysis

NASA Technical Reports Server (NTRS)

Dong, D.; Fang, P.; Bock, F.; Webb, F.; Prawirondirdjo, L.; Kedar, S.; Jamason, P.

2006-01-01

Spatial filtering is an effective way to improve the precision of coordinate time series for regional GPS networks by reducing so-called common mode errors, thereby providing better resolution for detecting weak or transient deformation signals. The commonly used approach to regional filtering assumes that the common mode error is spatially uniform, which is a good approximation for networks of hundreds of kilometers extent, but breaks down as the spatial extent increases. A more rigorous approach should remove the assumption of spatially uniform distribution and let the data themselves reveal the spatial distribution of the common mode error. The principal component analysis (PCA) and the Karhunen-Loeve expansion (KLE) both decompose network time series into a set of temporally varying modes and their spatial responses. Therefore they provide a mathematical framework to perform spatiotemporal filtering.We apply the combination of PCA and KLE to daily station coordinate time series of the Southern California Integrated GPS Network (SCIGN) for the period 2000 to 2004. We demonstrate that spatially and temporally correlated common mode errors are the dominant error source in daily GPS solutions. The spatial characteristics of the common mode errors are close to uniform for all east, north, and vertical components, which implies a very long wavelength source for the common mode errors, compared to the spatial extent of the GPS network in southern California. Furthermore, the common mode errors exhibit temporally nonrandom patterns.

Subject-based discriminative sparse representation model for detection of concealed information.

PubMed

Akhavan, Amir; Moradi, Mohammad Hassan; Vand, Safa Rafiei

2017-05-01

The use of machine learning approaches in concealed information test (CIT) plays a key role in the progress of this neurophysiological field. In this paper, we presented a new machine learning method for CIT in which each subject is considered independent of the others. The main goal of this study is to adapt the discriminative sparse models to be applicable for subject-based concealed information test. In order to provide sufficient discriminability between guilty and innocent subjects, we introduced a novel discriminative sparse representation model and its appropriate learning methods. For evaluation of the method forty-four subjects participated in a mock crime scenario and their EEG data were recorded. As the model input, in this study the recurrence plot features were extracted from single trial data of different stimuli. Then the extracted feature vectors were reduced using statistical dependency method. The reduced feature vector went through the proposed subject-based sparse model in which the discrimination power of sparse code and reconstruction error were applied simultaneously. Experimental results showed that the proposed approach achieved better performance than other competing discriminative sparse models. The classification accuracy, sensitivity and specificity of the presented sparsity-based method were about 93%, 91% and 95% respectively. Using the EEG data of a single subject in response to different stimuli types and with the aid of the proposed discriminative sparse representation model, one can distinguish guilty subjects from innocent ones. Indeed, this property eliminates the necessity of several subject EEG data in model learning and decision making for a specific subject. Copyright © 2017 Elsevier B.V. All rights reserved.

Concealing Concealment: The Mediating Role of Internalized Heterosexism in Psychological Distress Among Lesbian, Gay, and Bisexual Older Adults

PubMed Central

Hoy-Ellis, Charles P.

2016-01-01

Recent population-based studies indicate that sexual minorities aged 50 and older experience significantly higher rates of psychological distress than their heterosexual age-peers. The minority stress model has been useful in explaining disparately high rates of psychological distress among younger sexual minorities. The purpose of this study is to test a hypothesized structural relationship between two minority stressors—internalized heterosexism and concealment of sexual orientation—and consequent psychological distress among a sample of 2,349 lesbian, gay, and bisexual adults aged 50 to 95 years old. Structural equation modeling indicates that concealment has a nonsignificant direct effect on psychological distress but a significant indirect effect that is mediated through internalized heterosexism; the effect of concealment is itself concealed. This may explain divergent results regarding the role of concealment in psychological distress in other studies, and the implications will be discussed. PMID:26322654

Wavelet Fusion for Concealed Object Detection Using Passive Millimeter Wave Sequence Images

NASA Astrophysics Data System (ADS)

Chen, Y.; Pang, L.; Liu, H.; Xu, X.

2018-04-01

PMMW imaging system can create interpretable imagery on the objects concealed under clothing, which gives the great advantage to the security check system. Paper addresses wavelet fusion to detect concealed objects using passive millimeter wave (PMMW) sequence images. According to PMMW real-time imager acquired image characteristics and storage methods firstly, using the sum of squared difference (SSD) as the image-related parameters to screen the sequence images. Secondly, the selected images are optimized using wavelet fusion algorithm. Finally, the concealed objects are detected by mean filter, threshold segmentation and edge detection. The experimental results show that this method improves the detection effect of concealed objects by selecting the most relevant images from PMMW sequence images and using wavelet fusion to enhance the information of the concealed objects. The method can be effectively applied to human body concealed object detection in millimeter wave video.

25 CFR 11.444 - Carrying concealed weapons.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Carrying concealed weapons. 11.444 Section 11.444 Indians... ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in public places armed with a dangerous weapon concealed upon his or her person is guilty of a misdemeanor unless...

25 CFR 11.444 - Carrying concealed weapons.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Carrying concealed weapons. 11.444 Section 11.444 Indians... ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in public places armed with a dangerous weapon concealed upon his or her person is guilty of a misdemeanor unless...

25 CFR 11.444 - Carrying concealed weapons.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Carrying concealed weapons. 11.444 Section 11.444 Indians... ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in public places armed with a dangerous weapon concealed upon his or her person is guilty of a misdemeanor unless...

25 CFR 11.444 - Carrying concealed weapons.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Carrying concealed weapons. 11.444 Section 11.444 Indians... ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in public places armed with a dangerous weapon concealed upon his or her person is guilty of a misdemeanor unless...

25 CFR 11.444 - Carrying concealed weapons.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Carrying concealed weapons. 11.444 Section 11.444 Indians... ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in public places armed with a dangerous weapon concealed upon his or her person is guilty of a misdemeanor unless...

Mental Layouts of Concealed Objects as a Function of Bizarre Imagery and Retention Interval.

ERIC Educational Resources Information Center

Iaccino, James; And Others

To determine whether concealed imagery was an effective mnemonic aid in the recall of paired objects, two studies were conducted with explicitly worded instructions to conceal targets and with variable image formation periods. In each study, 40 subjects were presented with counterbalanced verbal descriptions of Concealed, Pictorial, and Separate…

Mapping Fearscapes of a Mammalian Herbivore using Terrestrial LiDAR and UAV Imagery

NASA Astrophysics Data System (ADS)

Olsoy, P.; Nobler, J. D.; Forbey, J.; Rachlow, J. L.; Burgess, M. A.; Glenn, N. F.; Shipley, L. A.

2013-12-01

Concealment allows prey animals to remain hidden from a predator and can influence both real and perceived risks of predation. The heterogeneous nature of vegetative structure can create a variable landscape of concealment - a 'fearscape' - that may influence habitat quality and use by prey. Traditional measurements of concealment rely on a limited number of distances, heights, and vantage points, resulting in small snapshots of concealment available to a prey animal. Our objective was to demonstrate the benefits of emerging remote sensing techniques to map fearscapes for pygmy rabbits (Brachylagus idahoensis) in sagebrush steppe habitat across a continuous range of scales. Specifically, we used vegetation height rasters derived from terrestrial laser scanning (TLS) to create viewsheds from multiple vantage points, representing predator visibility. The sum of all the viewsheds modeled horizontal concealment of prey at both the shrub and patch scales. We also used a small, unmanned aerial vehicle (UAV) to determine vertical concealment at a habitat scale. Terrestrial laser scanning provided similar estimates of horizontal concealment at the shrub scale when compared to photographic methods (R2 = 0.85). Both TLS and UAV provide the potential to quantify concealment of prey from multiple distances, heights, or vantage points, allowing the creation of a manipulable fearscape map that can be correlated with habitat use by prey animals. The predictive power of such a map also could identify shrubs or patches for fine scale nutritional and concealment analysis for future investigation and conservation efforts. Fearscape map at the mound-scale. Viewsheds were calculated from 100 equally spaced observer points located 4 m from the closest on-mound sagebrush of interest. Red areas offer low concealment, while green areas provide high concealment.

Students’ Errors in Geometry Viewed from Spatial Intelligence

NASA Astrophysics Data System (ADS)

Riastuti, N.; Mardiyana, M.; Pramudya, I.

2017-09-01

Geometry is one of the difficult materials because students must have ability to visualize, describe images, draw shapes, and know the kind of shapes. This study aim is to describe student error based on Newmans’ Error Analysis in solving geometry problems viewed from spatial intelligence. This research uses descriptive qualitative method by using purposive sampling technique. The datas in this research are the result of geometri material test and interview by the 8th graders of Junior High School in Indonesia. The results of this study show that in each category of spatial intelligence has a different type of error in solving the problem on the material geometry. Errors are mostly made by students with low spatial intelligence because they have deficiencies in visual abilities. Analysis of student error viewed from spatial intelligence is expected to help students do reflection in solving the problem of geometry.

Campaign for Right to Carry Concealed Guns on Campuses Gains Traction

ERIC Educational Resources Information Center

Wiseman, Rachel

2012-01-01

Five years after the Virginia Tech massacre prompted a student in Texas to start a Facebook page in favor of the right to carry concealed weapons on college campuses, the resulting group, Students for Concealed Carry, has advanced its cause. In more than a dozen states, legislation has been introduced to allow the carrying of concealed firearms on…

Regulatory focus moderates the social performance of individuals who conceal a stigmatized identity.

PubMed

Newheiser, Anna-Kaisa; Barreto, Manuela; Ellemers, Naomi; Derks, Belle; Scheepers, Daan

2015-12-01

People often choose to hide a stigmatized identity to avoid bias. However, hiding stigma can disrupt social interactions. We considered whether regulatory focus qualifies the social effects of hiding stigma by examining interactions in which stigmatized participants concealed a devalued identity from non-stigmatized partners. In the Prevention Focus condition, stigmatized participants were instructed to prevent a negative impression by concealing the identity; in the Promotion Focus condition, they were instructed to promote a positive impression by concealing the identity; in the Control condition, they were simply asked to conceal the identity. Both non-stigmatized partners and independent raters rated the interactions more positively in the Promotion Focus condition. Thus, promotion focus is interpersonally beneficial for individuals who conceal a devalued identity. © 2015 The British Psychological Society.

Attachment style, self-concealment, and interpersonal distance among Japanese undergraduates.

PubMed

Yukawa, Shintaro; Tokuda, Hideji; Sato, Jun

2007-06-01

The relationships among attachment style, self-concealment, and interpersonal distance were studied with 71 Japanese undergraduates (33 men and 38 women, ages 18 to 20 years, M = 18.7, SD= .6). Participants completed a questionnaire about Self-concealment and Attachment Styles (Secure, Anxious, and Avoidant). One week later, Interpersonal Distance, which individuals maintain between themselves and others, was measured by the stop-distance paradigm. Analysis showed that scores for more Anxious and Avoidant Attachment Styles were positively correlated with those for greater Self-concealment. Scores for greater Self-concealment and more Anxious Attachment Style were also correlated with longer Interpersonal Distance.

Canceling the momentum in a phase-shifting algorithm to eliminate spatially uniform errors.

PubMed

Hibino, Kenichi; Kim, Yangjin

2016-08-10

In phase-shifting interferometry, phase modulation nonlinearity causes both spatially uniform and nonuniform errors in the measured phase. Conventional linear-detuning error-compensating algorithms only eliminate the spatially variable error component. The uniform error is proportional to the inertial momentum of the data-sampling weight of a phase-shifting algorithm. This paper proposes a design approach to cancel the momentum by using characteristic polynomials in the Z-transform space and shows that an arbitrary M-frame algorithm can be modified to a new (M+2)-frame algorithm that acquires new symmetry to eliminate the uniform error.

Accounting for the measurement error of spectroscopically inferred soil carbon data for improved precision of spatial predictions.

PubMed

Somarathna, P D S N; Minasny, Budiman; Malone, Brendan P; Stockmann, Uta; McBratney, Alex B

2018-08-01

Spatial modelling of environmental data commonly only considers spatial variability as the single source of uncertainty. In reality however, the measurement errors should also be accounted for. In recent years, infrared spectroscopy has been shown to offer low cost, yet invaluable information needed for digital soil mapping at meaningful spatial scales for land management. However, spectrally inferred soil carbon data are known to be less accurate compared to laboratory analysed measurements. This study establishes a methodology to filter out the measurement error variability by incorporating the measurement error variance in the spatial covariance structure of the model. The study was carried out in the Lower Hunter Valley, New South Wales, Australia where a combination of laboratory measured, and vis-NIR and MIR inferred topsoil and subsoil soil carbon data are available. We investigated the applicability of residual maximum likelihood (REML) and Markov Chain Monte Carlo (MCMC) simulation methods to generate parameters of the Matérn covariance function directly from the data in the presence of measurement error. The results revealed that the measurement error can be effectively filtered-out through the proposed technique. When the measurement error was filtered from the data, the prediction variance almost halved, which ultimately yielded a greater certainty in spatial predictions of soil carbon. Further, the MCMC technique was successfully used to define the posterior distribution of measurement error. This is an important outcome, as the MCMC technique can be used to estimate the measurement error if it is not explicitly quantified. Although this study dealt with soil carbon data, this method is amenable for filtering the measurement error of any kind of continuous spatial environmental data. Copyright © 2018 Elsevier B.V. All rights reserved.

Concealing Emotions at Work Is Associated with Allergic Rhinitis in Korea.

PubMed

Seok, Hongdeok; Yoon, Jin-Ha; Won, Jong-Uk; Lee, Wanhyung; Lee, June-Hee; Jung, Pil Kyun; Roh, Jaehoon

2016-01-01

Concealing emotions at work can cause considerable psychological stress. While there is extensive research on the adverse health effects of concealing emotions and the association between allergic diseases and stress, research has not yet investigated whether concealing emotions at work is associated with allergic rhinitis. Allergic rhinitis is a common disease in many industrialized countries, and its prevalence is increasing. Thus, our aim was to determine the strength of this association using data from three years (2007-2009) of the 4th Korean National Health and Nutrition Examination Survey. Participants (aged 20-64) were 8,345 individuals who were economically active and who had completed the questionnaire items on concealing emotions at work. Odds ratio (OR) and 95% confidence intervals (95% CIs) were calculated for allergic rhinitis using logistic regression models. Among all participants, 3,140 subjects (37.6%) reported concealing their emotions at work: 1,661 men and 1,479 women. The OR (95% CIs) for allergic rhinitis among those who concealed emotions at work versus those who did not was 1.318 (1.148-1.512). Stratified by sex, the OR (95% CIs) was 1.307 (1.078-1.585) among men and 1.346 (1.105-1.639) among women. Thus, individuals who concealed their emotions at work were significantly more likely to have a diagnosis of AR in comparison to those who did not. Because concealing emotions at work has adverse health effects, labor policies that aim to reduce this practice are needed.

Diving into the consumer nutrition environment: A Bayesian spatial factor analysis of neighborhood restaurant environment.

PubMed

Luan, Hui; Law, Jane; Lysy, Martin

2018-02-01

Neighborhood restaurant environment (NRE) plays a vital role in shaping residents' eating behaviors. While NRE 'healthfulness' is a multi-facet concept, most studies evaluate it based only on restaurant type, thus largely ignoring variations of in-restaurant features. In the few studies that do account for such features, healthfulness scores are simply averaged over accessible restaurants, thereby concealing any uncertainty that attributed to neighborhoods' size or spatial correlation. To address these limitations, this paper presents a Bayesian Spatial Factor Analysis for assessing NRE healthfulness in the city of Kitchener, Canada. Several in-restaurant characteristics are included. By treating NRE healthfulness as a spatially correlated latent variable, the adopted modeling approach can: (i) identify specific indicators most relevant to NRE healthfulness, (ii) provide healthfulness estimates for neighborhoods without accessible restaurants, and (iii) readily quantify uncertainties in the healthfulness index. Implications of the analysis for intervention program development and community food planning are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Verriest Lecture: Color lessons from space, time, and motion

PubMed Central

Shevell, Steven K.

2012-01-01

The appearance of a chromatic stimulus depends on more than the wavelengths composing it. The scientific literature has countless examples showing that spatial and temporal features of light influence the colors we see. Studying chromatic stimuli that vary over space, time or direction of motion has a further benefit beyond predicting color appearance: the unveiling of otherwise concealed neural processes of color vision. Spatial or temporal stimulus variation uncovers multiple mechanisms of brightness and color perception at distinct levels of the visual pathway. Spatial variation in chromaticity and luminance can change perceived three-dimensional shape, an example of chromatic signals that affect a percept other than color. Chromatic objects in motion expose the surprisingly weak link between the chromaticity of objects and their physical direction of motion, and the role of color in inducing an illusory motion direction. Space, time and motion – color’s colleagues – reveal the richness of chromatic neural processing. PMID:22330398

Method for imaging a concealed object

DOEpatents

Davidson, James R [Idaho Falls, ID; Partin, Judy K [Idaho Falls, ID; Sawyers, Robert J [Idaho Falls, ID

2007-07-03

A method for imaging a concealed object is described and which includes a step of providing a heat radiating body, and wherein an object to be detected is concealed on the heat radiating body; imaging the heat radiating body to provide a visibly discernible infrared image of the heat radiating body; and determining if the visibly discernible infrared image of the heat radiating body is masked by the presence of the concealed object.

TeraSCREEN: multi-frequency multi-mode Terahertz screening for border checks

NASA Astrophysics Data System (ADS)

Alexander, Naomi E.; Alderman, Byron; Allona, Fernando; Frijlink, Peter; Gonzalo, Ramón; Hägelen, Manfred; Ibáñez, Asier; Krozer, Viktor; Langford, Marian L.; Limiti, Ernesto; Platt, Duncan; Schikora, Marek; Wang, Hui; Weber, Marc Andree

2014-06-01

The challenge for any security screening system is to identify potentially harmful objects such as weapons and explosives concealed under clothing. Classical border and security checkpoints are no longer capable of fulfilling the demands of today's ever growing security requirements, especially with respect to the high throughput generally required which entails a high detection rate of threat material and a low false alarm rate. TeraSCREEN proposes to develop an innovative concept of multi-frequency multi-mode Terahertz and millimeter-wave detection with new automatic detection and classification functionalities. The system developed will demonstrate, at a live control point, the safe automatic detection and classification of objects concealed under clothing, whilst respecting privacy and increasing current throughput rates. This innovative screening system will combine multi-frequency, multi-mode images taken by passive and active subsystems which will scan the subjects and obtain complementary spatial and spectral information, thus allowing for automatic threat recognition. The TeraSCREEN project, which will run from 2013 to 2016, has received funding from the European Union's Seventh Framework Programme under the Security Call. This paper will describe the project objectives and approach.

Spatial durbin error model for human development index in Province of Central Java.

NASA Astrophysics Data System (ADS)

Septiawan, A. R.; Handajani, S. S.; Martini, T. S.

2018-05-01

The Human Development Index (HDI) is an indicator used to measure success in building the quality of human life, explaining how people access development outcomes when earning income, health and education. Every year HDI in Central Java has improved to a better direction. In 2016, HDI in Central Java was 69.98 %, an increase of 0.49 % over the previous year. The objective of this study was to apply the spatial Durbin error model using angle weights queen contiguity to measure HDI in Central Java Province. Spatial Durbin error model is used because the model overcomes the spatial effect of errors and the effects of spatial depedency on the independent variable. Factors there use is life expectancy, mean years of schooling, expected years of schooling, and purchasing power parity. Based on the result of research, we get spatial Durbin error model for HDI in Central Java with influencing factors are life expectancy, mean years of schooling, expected years of schooling, and purchasing power parity.

Bayesian learning for spatial filtering in an EEG-based brain-computer interface.

PubMed

Zhang, Haihong; Yang, Huijuan; Guan, Cuntai

2013-07-01

Spatial filtering for EEG feature extraction and classification is an important tool in brain-computer interface. However, there is generally no established theory that links spatial filtering directly to Bayes classification error. To address this issue, this paper proposes and studies a Bayesian analysis theory for spatial filtering in relation to Bayes error. Following the maximum entropy principle, we introduce a gamma probability model for describing single-trial EEG power features. We then formulate and analyze the theoretical relationship between Bayes classification error and the so-called Rayleigh quotient, which is a function of spatial filters and basically measures the ratio in power features between two classes. This paper also reports our extensive study that examines the theory and its use in classification, using three publicly available EEG data sets and state-of-the-art spatial filtering techniques and various classifiers. Specifically, we validate the positive relationship between Bayes error and Rayleigh quotient in real EEG power features. Finally, we demonstrate that the Bayes error can be practically reduced by applying a new spatial filter with lower Rayleigh quotient.

A method to estimate the effect of deformable image registration uncertainties on daily dose mapping

PubMed Central

Murphy, Martin J.; Salguero, Francisco J.; Siebers, Jeffrey V.; Staub, David; Vaman, Constantin

2012-01-01

Purpose: To develop a statistical sampling procedure for spatially-correlated uncertainties in deformable image registration and then use it to demonstrate their effect on daily dose mapping. Methods: Sequential daily CT studies are acquired to map anatomical variations prior to fractionated external beam radiotherapy. The CTs are deformably registered to the planning CT to obtain displacement vector fields (DVFs). The DVFs are used to accumulate the dose delivered each day onto the planning CT. Each DVF has spatially-correlated uncertainties associated with it. Principal components analysis (PCA) is applied to measured DVF error maps to produce decorrelated principal component modes of the errors. The modes are sampled independently and reconstructed to produce synthetic registration error maps. The synthetic error maps are convolved with dose mapped via deformable registration to model the resulting uncertainty in the dose mapping. The results are compared to the dose mapping uncertainty that would result from uncorrelated DVF errors that vary randomly from voxel to voxel. Results: The error sampling method is shown to produce synthetic DVF error maps that are statistically indistinguishable from the observed error maps. Spatially-correlated DVF uncertainties modeled by our procedure produce patterns of dose mapping error that are different from that due to randomly distributed uncertainties. Conclusions: Deformable image registration uncertainties have complex spatial distributions. The authors have developed and tested a method to decorrelate the spatial uncertainties and make statistical samples of highly correlated error maps. The sample error maps can be used to investigate the effect of DVF uncertainties on daily dose mapping via deformable image registration. An initial demonstration of this methodology shows that dose mapping uncertainties can be sensitive to spatial patterns in the DVF uncertainties. PMID:22320766

Direct and indirect links between parenting styles, self-concealment (secrets), impaired control over drinking and alcohol-related outcomes.

PubMed

Hartman, Jessica D; Patock-Peckham, Julie A; Corbin, William R; Gates, Jonathan R; Leeman, Robert F; Luk, Jeremy W; King, Kevin M

2015-01-01

Self-concealment reflects uncomfortable feelings, thoughts, and information people have about themselves that they avoid telling others (Larson & Chastain, 1990). According to Larson and Chastain (1990) these secrets range from the slightly embarrassing to the very distressing with an individual's most traumatic experiences often concealed. Parental attitudes including those involving self-disclosure are thought to be expressed in their choice of parenting style (Brand, Hatzinger, Beck, & Holsboer-Trachsler, 2009). The specific aim of this investigation was to examine the direct and indirect influences of parenting styles on self-concealment, impaired control over drinking (i.e. the inability to stop drinking when intended), alcohol use (quantity/frequency), and alcohol-related problems. A structural equation model with 419 (223 men, 196 women) university students was examined. Two and three path mediated effects were examined with the bias corrected bootstrap technique in Mplus. Having an authoritarian mother was directly linked to more self-concealment, while having an authoritative father was directly linked to less self-concealment. Higher levels of mother authoritarianism were indirectly linked to both increased alcohol use and alcohol-related problems through more self-concealment and more impaired control over drinking. Moreover, higher levels of father authoritativeness were indirectly linked to less alcohol use and alcohol-related problems through less self-concealment and less impaired control over drinking. These findings suggest that parenting styles influence vulnerabilities such as self-concealment in the impaired control over the drinking pathway to alcohol use and alcohol-related problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Disclosure and concealment of sexual orientation and the mental health of non-gay-identified, behaviorally bisexual men.

PubMed

Schrimshaw, Eric W; Siegel, Karolynn; Downing, Martin J; Parsons, Jeffrey T

2013-02-01

Although bisexual men report lower levels of mental health relative to gay men, few studies have examined the factors that contribute to bisexual men's mental health. Bisexual men are less likely to disclose, and more likely to conceal (i.e., a desire to hide), their sexual orientation than gay men. Theory suggests that this may adversely impact their mental health. This report examined the factors associated with disclosure and with concealment of sexual orientation, the association of disclosure and concealment with mental health, and the potential mediators (i.e., internalized homophobia, social support) of this association with mental health. An ethnically diverse sample of 203 non-gay-identified, behaviorally bisexual men who do not disclose their same-sex behavior to their female partners were recruited in New York City to complete a single set of self-report measures. Concealment was associated with higher income, a heterosexual identification, living with a wife or girlfriend, more frequent sex with women, and less frequent sex with men. Greater concealment, but not disclosure to friends and family, was significantly associated with lower levels of mental health. Multiple mediation analyses revealed that both internalized homophobia and general emotional support significantly mediated the association between concealment and mental health. The findings demonstrate that concealment and disclosure are independent constructs among bisexual men. Further, they suggest that interventions addressing concerns about concealment, emotional support, and internalized homophobia may be more beneficial for increasing the mental health of bisexual men than those focused on promoting disclosure.

Disclosure and Concealment of Sexual Orientation and the Mental Health of Non-Gay-Identified, Behaviorally-Bisexual Men

PubMed Central

Schrimshaw, Eric W.; Siegel, Karolynn; Downing, Martin J.; Parsons, Jeffrey T.

2013-01-01

Objective Although bisexual men report lower levels of mental health relative to gay men, few studies have examined the factors that contribute to bisexual men’s mental health. Bisexual men are less likely to disclose, and more likely to conceal (i.e., a desire to hide), their sexual orientation than gay men. Theory suggests that this may adversely impact their mental health. This report examined the factors associated with disclosure and with concealment of sexual orientation, the association of disclosure and concealment with mental health, and the potential mediators (i.e., internalized homophobia, social support) of this association with mental health. Method An ethnically-diverse sample of 203 non-gay-identified, behaviorally-bisexual men who do not disclose their same-sex behavior to their female partners were recruited in New York City to complete a single set of self-report measures. Results Concealment was associated with higher income, a heterosexual identification, living with a wife or girlfriend, more frequent sex with women, and less frequent sex with men. Greater concealment, but not disclosure to friends and family, was significantly associated with lower levels of mental health. Multiple mediation analyses revealed that both internalized homophobia and general emotional support significantly mediated the association between concealment and mental health. Conclusions The findings demonstrate that concealment and disclosure are independent constructs among bisexual men. Further, they suggest that interventions addressing concerns about concealment, emotional support, and internalized homophobia may be more beneficial for increasing the mental health of bisexual men than those focused on promoting disclosure. PMID:23276123

Fourier decomposition of spatial localization errors reveals an idiotropic dominance of an internal model of gravity.

PubMed

De Sá Teixeira, Nuno Alexandre

2014-12-01

Given its conspicuous nature, gravity has been acknowledged by several research lines as a prime factor in structuring the spatial perception of one's environment. One such line of enquiry has focused on errors in spatial localization aimed at the vanishing location of moving objects - it has been systematically reported that humans mislocalize spatial positions forward, in the direction of motion (representational momentum) and downward in the direction of gravity (representational gravity). Moreover, spatial localization errors were found to evolve dynamically with time in a pattern congruent with an anticipated trajectory (representational trajectory). The present study attempts to ascertain the degree to which vestibular information plays a role in these phenomena. Human observers performed a spatial localization task while tilted to varying degrees and referring to the vanishing locations of targets moving along several directions. A Fourier decomposition of the obtained spatial localization errors revealed that although spatial errors were increased "downward" mainly along the body's longitudinal axis (idiotropic dominance), the degree of misalignment between the latter and physical gravity modulated the time course of the localization responses. This pattern is surmised to reflect increased uncertainty about the internal model when faced with conflicting cues regarding the perceived "downward" direction.

Detecting Spatial Patterns in Biological Array Experiments

PubMed Central

ROOT, DAVID E.; KELLEY, BRIAN P.; STOCKWELL, BRENT R.

2005-01-01

Chemical genetic screening and DNA and protein microarrays are among a number of increasingly important and widely used biological research tools that involve large numbers of parallel experiments arranged in a spatial array. It is often difficult to ensure that uniform experimental conditions are present throughout the entire array, and as a result, one often observes systematic spatially correlated errors, especially when array experiments are performed using robots. Here, the authors apply techniques based on the discrete Fourier transform to identify and quantify spatially correlated errors superimposed on a spatially random background. They demonstrate that these techniques are effective in identifying common spatially systematic errors in high-throughput 384-well microplate assay data. In addition, the authors employ a statistical test to allow for automatic detection of such errors. Software tools for using this approach are provided. PMID:14567791

Geometry, structure, and concealed lithology of the San Rafael Basin, southeastern Arizona

USGS Publications Warehouse

Bultman, Mark W.

1999-01-01

The contiguous United States has been well explored for exposed conventional mineral deposits. Therefore, it is likely that many economically viable and strategically significant conventional undiscovered mineral deposits will be found in bedrock concealed beneath basin sediments. Mineral resource assessments must incorporate an understanding of the geometry, structure, and concealed lithology of basins in order to be accurate. This report presents an analysis of the basin geometry and structure of the San Rafael basin in southeastern Arizona. In addition, a new methodology for inferring concealed lithology is presented and applied in the San Rafael basin. Gravity data is used to model the geometry of the basin using recent models of sediment density vs. depth developed in the region. This modeling indicates that the basin has a maximum depth of approximately 1.05 km plus or minus 0.10 km. In the southern portion, the basin can be modeled as an asymmetric graben faulted on the western margin. The northern portion of the basin is structurally more complex and may have high angle faults on the western, northern, and eastern margin. Near-ground closely spaced Earth’s total intensity magnetic field data is used to locate concealed faults within the basin. This data is also used to infer lithology concealed by shallow basin sediments. Airborne Earth’s total intensity magnetic field data is used to help infer concealed lithology in deep portions of the basin. The product of integrating all data and interpretations is a map which presents the geometry of the basin, faults and contacts concealed by basin sediments, and an estimate of the bedrock lithology concealed by basin sediment. Based on basin geometry and concealed lithology, the San Rafael basin has a high potential for concealed mineral deposits on its western and northern margin. In particular, a newly discovered magnetic anomaly in the northern portion of the basin can be modeled as a granitic intrusion with highly altered margins and may represent a potential mineral resource target. Based on the permeability and porosity of upper basin fill found in nearby basins, the San Rafael basin may contain an aquifer up to 300 meters thick over a substantial area of the basin.

Multi-photon self-error-correction hyperentanglement distribution over arbitrary collective-noise channels

NASA Astrophysics Data System (ADS)

Gao, Cheng-Yan; Wang, Guan-Yu; Zhang, Hao; Deng, Fu-Guo

2017-01-01

We present a self-error-correction spatial-polarization hyperentanglement distribution scheme for N-photon systems in a hyperentangled Greenberger-Horne-Zeilinger state over arbitrary collective-noise channels. In our scheme, the errors of spatial entanglement can be first averted by encoding the spatial-polarization hyperentanglement into the time-bin entanglement with identical polarization and defined spatial modes before it is transmitted over the fiber channels. After transmission over the noisy channels, the polarization errors introduced by the depolarizing noise can be corrected resorting to the time-bin entanglement. Finally, the parties in quantum communication can in principle share maximally hyperentangled states with a success probability of 100%.

Spatial Representativeness Error in the Ground-Level Observation Networks for Black Carbon Radiation Absorption

NASA Astrophysics Data System (ADS)

Wang, Rong; Andrews, Elisabeth; Balkanski, Yves; Boucher, Olivier; Myhre, Gunnar; Samset, Bjørn Hallvard; Schulz, Michael; Schuster, Gregory L.; Valari, Myrto; Tao, Shu

2018-02-01

There is high uncertainty in the direct radiative forcing of black carbon (BC), an aerosol that strongly absorbs solar radiation. The observation-constrained estimate, which is several times larger than the bottom-up estimate, is influenced by the spatial representativeness error due to the mesoscale inhomogeneity of the aerosol fields and the relatively low resolution of global chemistry-transport models. Here we evaluated the spatial representativeness error for two widely used observational networks (AErosol RObotic NETwork and Global Atmosphere Watch) by downscaling the geospatial grid in a global model of BC aerosol absorption optical depth to 0.1° × 0.1°. Comparing the models at a spatial resolution of 2° × 2° with BC aerosol absorption at AErosol RObotic NETwork sites (which are commonly located near emission hot spots) tends to cause a global spatial representativeness error of 30%, as a positive bias for the current top-down estimate of global BC direct radiative forcing. By contrast, the global spatial representativeness error will be 7% for the Global Atmosphere Watch network, because the sites are located in such a way that there are almost an equal number of sites with positive or negative representativeness error.

Spatial and temporal variability of the overall error of National Atmospheric Deposition Program measurements determined by the USGS collocated-sampler program, water years 1989-2001

USGS Publications Warehouse

Wetherbee, G.A.; Latysh, N.E.; Gordon, J.D.

2005-01-01

Data from the U.S. Geological Survey (USGS) collocated-sampler program for the National Atmospheric Deposition Program/National Trends Network (NADP/NTN) are used to estimate the overall error of NADP/NTN measurements. Absolute errors are estimated by comparison of paired measurements from collocated instruments. Spatial and temporal differences in absolute error were identified and are consistent with longitudinal distributions of NADP/NTN measurements and spatial differences in precipitation characteristics. The magnitude of error for calcium, magnesium, ammonium, nitrate, and sulfate concentrations, specific conductance, and sample volume is of minor environmental significance to data users. Data collected after a 1994 sample-handling protocol change are prone to less absolute error than data collected prior to 1994. Absolute errors are smaller during non-winter months than during winter months for selected constituents at sites where frozen precipitation is common. Minimum resolvable differences are estimated for different regions of the USA to aid spatial and temporal watershed analyses.

Concealed object segmentation and three-dimensional localization with passive millimeter-wave imaging

NASA Astrophysics Data System (ADS)

Yeom, Seokwon

2013-05-01

Millimeter waves imaging draws increasing attention in security applications for weapon detection under clothing. In this paper, concealed object segmentation and three-dimensional localization schemes are reviewed. A concealed object is segmented by the k-means algorithm. A feature-based stereo-matching method estimates the longitudinal distance of the concealed object. The distance is estimated by the discrepancy between the corresponding centers of the segmented objects. Experimental results are provided with the analysis of the depth resolution.

Guilt, censure, and concealment of active smoking status among cancer patients and family members after diagnosis: a nationwide study.

PubMed

Shin, Dong Wook; Park, Jong Hyock; Kim, So Young; Park, Eal Whan; Yang, Hyung Kook; Ahn, Eunmi; Park, Seon Mee; Lee, Young Joon; Lim, Myong Cheol; Seo, Hong Gwan

2014-05-01

We aimed to identify the prevalence of feelings of guilt, censure, and concealment of smoking status among cancer patients and their family members who continued to smoke after the patient's diagnosis. Among 990 patient-family member dyads, 45 patients and 173 family members who continued to smoke for at least 1 month after the patients' diagnoses were administered questions examining feelings of guilt, censure, and smoking concealment. Most patients who continued to smoke reported experiencing feelings of guilt toward their families (75.6%) and censure from their family members (77.8%), and many concealed their smoking from their family members (44.4%) or healthcare professionals (46.7%). Family members who continued to smoke also reported feelings of guilt with respect to the patient (63.6%) and that the patient was critical of them (68.9%), and many concealed their smoking from the patient (28.5%) or healthcare professionals (9.3%). Patients' feeling of guilt was associated with concealment of smoking from family members (55.9% vs. 10.0%) or health care professionals (55.9% vs. 20.0%). Family members who reported feeling guilty (36.5% vs. 16.3%) or censured (34.5% vs. 16.7%) were more likely to conceal smoking from patients. Many patients and family members continue to smoke following cancer diagnosis, and the majority of them experience feelings of guilt and censure, which can lead to the concealment of smoking status from families or health care professionals. Feelings of guilt, censure, and concealment of smoking should be considered in the development and implementation of smoking cessation programs for cancer patients and family members. Copyright © 2013 John Wiley & Sons, Ltd.

Management of a concealable stigmatized identity: A qualitative study of concealment, disclosure and role flexing among young, resilient sexual and gender minority individuals

PubMed Central

Bry, Laura Jane; Mustanski, Brian; Garofalo, Robert; Burns, Michelle Nicole

2017-01-01

Disclosure of a sexual or gender minority status has been associated with both positive and negative effects on wellbeing. Few studies have explored the disclosure and concealment process in young people. Interviews were conducted with 10 sexual and/or gender minority individuals, aged 18–22 years, of male birth sex. Data were analyzed qualitatively, yielding determinants and effects of disclosure and concealment. Determinants of disclosure included holding positive attitudes about one’s identity and an implicit devaluation of acceptance by society. Coming out was shown to have both positive and negative effects on communication and social support, and was associated with both increases and decreases in experiences of stigma. Determinants of concealment included lack of comfort with one’s identity and various motivations to avoid discrimination. Concealment was also related to hypervigilance and unique strategies of accessing social support. Results are discussed in light of their clinical implications. PMID:27633070

A Qualitative Study Examining Experiences and Dilemmas in Concealment and Disclosure of People Living With Serious Mental Illness.

PubMed

Bril-Barniv, Shani; Moran, Galia S; Naaman, Adi; Roe, David; Karnieli-Miller, Orit

2017-03-01

People with mental illnesses face the dilemma of whether to disclose or conceal their diagnosis, but this dilemma was scarcely researched. To gain in-depth understanding of this dilemma, we interviewed 29 individuals with mental illnesses: 16 with major depression/bipolar disorders and 13 with schizophrenia. Using a phenomenological design, we analyzed individuals' experiences, decision-making processes, and views of gains and costs regarding concealment and disclosure of mental illness. We found that participants employed both positive and negative disclosure/concealment practices. Positive practices included enhancing personal recovery, community integration, and/or supporting others. Negative practices occurred in forced, uncontrolled situations. We also identified various influencing factors, including familial norms of sharing, accumulated experiences with disclosure, and ascribed meaning to diagnosis. Based on these findings, we deepen the understanding about decision-making processes and the consequences of disclosing or concealing mental illness. We discuss how these finding can help consumers explore potential benefits and disadvantages of mental illness disclosure/concealment occurrences.

Physician Beliefs about Physical and Mental Competency of Patients Applying for Concealed Weapon Permits.

PubMed

Goldstein, Adam O; Viera, Anthony J; Pierson, John; Barnhouse, Kathy K; Tulsky, James A; Richman, Barak D

2015-06-01

Law enforcement officials have asked health care providers to evaluate patient applications for concealed weapon permits. The current study was designed to examine physician beliefs regarding competency to carry a concealed weapon for patients with specific physical and mental conditions. Among 222 North Carolina physicians who participated in this survey (40% response rate), large variation and uncertainty existed for determining competency. Physicians most frequently chose mild dementia, post-traumatic stress disorder, and recent depression as conditions that would render a patient not competent to carry a concealed weapon. Male physicians and those owning a gun were more likely to deem a patient competent. Almost a third of physicians were unsure about competence for most conditions. Physicians asked to assess competency of patients to carry a concealed weapon have quite disparate views on competency and little confidence in their decisions. If physicians are expected to assess patient competence to carry a concealed weapon, more objective criteria and training are needed. Copyright © 2015 John Wiley & Sons, Ltd.

Management of a Concealable Stigmatized Identity: A Qualitative Study of Concealment, Disclosure, and Role Flexing Among Young, Resilient Sexual and Gender Minority Individuals.

PubMed

Bry, Laura Jane; Mustanski, Brian; Garofalo, Robert; Burns, Michelle Nicole

2017-01-01

Disclosure of a sexual or gender minority status has been associated with both positive and negative effects on wellbeing. Few studies have explored the disclosure and concealment process in young people. Interviews were conducted with 10 sexual and/or gender minority individuals, aged 18-22 years, of male birth sex. Data were analyzed qualitatively, yielding determinants and effects of disclosure and concealment. Determinants of disclosure included holding positive attitudes about one's identity and an implicit devaluation of acceptance by society. Coming out was shown to have both positive and negative effects on communication and social support and was associated with both increases and decreases in experiences of stigma. Determinants of concealment included lack of comfort with one's identity and various motivations to avoid discrimination. Concealment was also related to hypervigilance and unique strategies of accessing social support. Results are discussed in light of their clinical implications.

Estimating Prediction Uncertainty from Geographical Information System Raster Processing: A User's Manual for the Raster Error Propagation Tool (REPTool)

USGS Publications Warehouse

Gurdak, Jason J.; Qi, Sharon L.; Geisler, Michael L.

2009-01-01

The U.S. Geological Survey Raster Error Propagation Tool (REPTool) is a custom tool for use with the Environmental System Research Institute (ESRI) ArcGIS Desktop application to estimate error propagation and prediction uncertainty in raster processing operations and geospatial modeling. REPTool is designed to introduce concepts of error and uncertainty in geospatial data and modeling and provide users of ArcGIS Desktop a geoprocessing tool and methodology to consider how error affects geospatial model output. Similar to other geoprocessing tools available in ArcGIS Desktop, REPTool can be run from a dialog window, from the ArcMap command line, or from a Python script. REPTool consists of public-domain, Python-based packages that implement Latin Hypercube Sampling within a probabilistic framework to track error propagation in geospatial models and quantitatively estimate the uncertainty of the model output. Users may specify error for each input raster or model coefficient represented in the geospatial model. The error for the input rasters may be specified as either spatially invariant or spatially variable across the spatial domain. Users may specify model output as a distribution of uncertainty for each raster cell. REPTool uses the Relative Variance Contribution method to quantify the relative error contribution from the two primary components in the geospatial model - errors in the model input data and coefficients of the model variables. REPTool is appropriate for many types of geospatial processing operations, modeling applications, and related research questions, including applications that consider spatially invariant or spatially variable error in geospatial data.

Entropy of space-time outcome in a movement speed-accuracy task.

PubMed

Hsieh, Tsung-Yu; Pacheco, Matheus Maia; Newell, Karl M

2015-12-01

The experiment reported was set-up to investigate the space-time entropy of movement outcome as a function of a range of spatial (10, 20 and 30 cm) and temporal (250-2500 ms) criteria in a discrete aiming task. The variability and information entropy of the movement spatial and temporal errors considered separately increased and decreased on the respective dimension as a function of an increment of movement velocity. However, the joint space-time entropy was lowest when the relative contribution of spatial and temporal task criteria was comparable (i.e., mid-range of space-time constraints), and it increased with a greater trade-off between spatial or temporal task demands, revealing a U-shaped function across space-time task criteria. The traditional speed-accuracy functions of spatial error and temporal error considered independently mapped to this joint space-time U-shaped entropy function. The trade-off in movement tasks with joint space-time criteria is between spatial error and timing error, rather than movement speed and accuracy. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluate error correction ability of magnetorheological finishing by smoothing spectral function

NASA Astrophysics Data System (ADS)

Wang, Jia; Fan, Bin; Wan, Yongjian; Shi, Chunyan; Zhuo, Bin

2014-08-01

Power Spectral Density (PSD) has been entrenched in optics design and manufacturing as a characterization of mid-high spatial frequency (MHSF) errors. Smoothing Spectral Function (SSF) is a newly proposed parameter that based on PSD to evaluate error correction ability of computer controlled optical surfacing (CCOS) technologies. As a typical deterministic and sub-aperture finishing technology based on CCOS, magnetorheological finishing (MRF) leads to MHSF errors inevitably. SSF is employed to research different spatial frequency error correction ability of MRF process. The surface figures and PSD curves of work-piece machined by MRF are presented. By calculating SSF curve, the correction ability of MRF for different spatial frequency errors will be indicated as a normalized numerical value.

Correction of mid-spatial-frequency errors by smoothing in spin motion for CCOS

NASA Astrophysics Data System (ADS)

Zhang, Yizhong; Wei, Chaoyang; Shao, Jianda; Xu, Xueke; Liu, Shijie; Hu, Chen; Zhang, Haichao; Gu, Haojin

2015-08-01

Smoothing is a convenient and efficient way to correct mid-spatial-frequency errors. Quantifying the smoothing effect allows improvements in efficiency for finishing precision optics. A series experiments in spin motion are performed to study the smoothing effects about correcting mid-spatial-frequency errors. Some of them use a same pitch tool at different spinning speed, and others at a same spinning speed with different tools. Introduced and improved Shu's model to describe and compare the smoothing efficiency with different spinning speed and different tools. From the experimental results, the mid-spatial-frequency errors on the initial surface were nearly smoothed out after the process in spin motion and the number of smoothing times can be estimated by the model before the process. Meanwhile this method was also applied to smooth the aspherical component, which has an obvious mid-spatial-frequency error after Magnetorheological Finishing processing. As a result, a high precision aspheric optical component was obtained with PV=0.1λ and RMS=0.01λ.

Spatial Representativeness Error in the Ground‐Level Observation Networks for Black Carbon Radiation Absorption

PubMed Central

Andrews, Elisabeth; Balkanski, Yves; Boucher, Olivier; Myhre, Gunnar; Samset, Bjørn Hallvard; Schulz, Michael; Schuster, Gregory L.; Valari, Myrto; Tao, Shu

2018-01-01

Abstract There is high uncertainty in the direct radiative forcing of black carbon (BC), an aerosol that strongly absorbs solar radiation. The observation‐constrained estimate, which is several times larger than the bottom‐up estimate, is influenced by the spatial representativeness error due to the mesoscale inhomogeneity of the aerosol fields and the relatively low resolution of global chemistry‐transport models. Here we evaluated the spatial representativeness error for two widely used observational networks (AErosol RObotic NETwork and Global Atmosphere Watch) by downscaling the geospatial grid in a global model of BC aerosol absorption optical depth to 0.1° × 0.1°. Comparing the models at a spatial resolution of 2° × 2° with BC aerosol absorption at AErosol RObotic NETwork sites (which are commonly located near emission hot spots) tends to cause a global spatial representativeness error of 30%, as a positive bias for the current top‐down estimate of global BC direct radiative forcing. By contrast, the global spatial representativeness error will be 7% for the Global Atmosphere Watch network, because the sites are located in such a way that there are almost an equal number of sites with positive or negative representativeness error. PMID:29937603

Self-Concealment Mediates the Relationship Between Perfectionism and Attitudes Toward Seeking Psychological Help Among Adolescents.

PubMed

Abdollahi, Abbas; Hosseinian, Simin; Beh-Pajooh, Ahmad; Carlbring, Per

2017-01-01

One of the biggest barriers in treating adolescents with mental health problems is their refusing to seek psychological help. This study was designed to examine the relationships between two forms of perfectionism, self-concealment and attitudes toward seeking psychological help and to test the mediating role of self-concealment in the relationship between perfectionism and attitudes toward seeking psychological help among Malaysian high school students. The participants were 475 Malaysian high school students from four high schools in Kuala Lumpur, Malaysia. Structural equation modelling results indicated that high school students with high levels of socially prescribed perfectionism, high levels of self-concealment, and low levels of self-oriented perfectionism reported negative attitudes toward seeking psychological help. Bootstrapping analysis showed that self-concealment emerged as a significant, full mediator in the link between socially prescribed perfectionism and attitudes toward seeking psychological help. Moderated mediation analysis also examined whether the results generalized across men and women. The results revealed that male students with socially prescribed perfectionism are more likely to engage in self-concealment, which in turn, leads to negative attitudes toward seeking psychological help more than their female counterparts. The results suggested that students high in socially prescribed perfectionism were more likely to engage in self-concealment and be less inclined to seek psychological help.

Randomized clinical trials in dentistry: Risks of bias, risks of random errors, reporting quality, and methodologic quality over the years 1955–2013

PubMed Central

Armijo-Olivo, Susan; Cummings, Greta G.; Amin, Maryam; Flores-Mir, Carlos

2017-01-01

Objectives To examine the risks of bias, risks of random errors, reporting quality, and methodological quality of randomized clinical trials of oral health interventions and the development of these aspects over time. Methods We included 540 randomized clinical trials from 64 selected systematic reviews. We extracted, in duplicate, details from each of the selected randomized clinical trials with respect to publication and trial characteristics, reporting and methodologic characteristics, and Cochrane risk of bias domains. We analyzed data using logistic regression and Chi-square statistics. Results Sequence generation was assessed to be inadequate (at unclear or high risk of bias) in 68% (n = 367) of the trials, while allocation concealment was inadequate in the majority of trials (n = 464; 85.9%). Blinding of participants and blinding of the outcome assessment were judged to be inadequate in 28.5% (n = 154) and 40.5% (n = 219) of the trials, respectively. A sample size calculation before the initiation of the study was not performed/reported in 79.1% (n = 427) of the trials, while the sample size was assessed as adequate in only 17.6% (n = 95) of the trials. Two thirds of the trials were not described as double blinded (n = 358; 66.3%), while the method of blinding was appropriate in 53% (n = 286) of the trials. We identified a significant decrease over time (1955–2013) in the proportion of trials assessed as having inadequately addressed methodological quality items (P < 0.05) in 30 out of the 40 quality criteria, or as being inadequate (at high or unclear risk of bias) in five domains of the Cochrane risk of bias tool: sequence generation, allocation concealment, incomplete outcome data, other sources of bias, and overall risk of bias. Conclusions The risks of bias, risks of random errors, reporting quality, and methodological quality of randomized clinical trials of oral health interventions have improved over time; however, further efforts that contribute to the development of more stringent methodology and detailed reporting of trials are still needed. PMID:29272315

Randomized clinical trials in dentistry: Risks of bias, risks of random errors, reporting quality, and methodologic quality over the years 1955-2013.

PubMed

Saltaji, Humam; Armijo-Olivo, Susan; Cummings, Greta G; Amin, Maryam; Flores-Mir, Carlos

2017-01-01

To examine the risks of bias, risks of random errors, reporting quality, and methodological quality of randomized clinical trials of oral health interventions and the development of these aspects over time. We included 540 randomized clinical trials from 64 selected systematic reviews. We extracted, in duplicate, details from each of the selected randomized clinical trials with respect to publication and trial characteristics, reporting and methodologic characteristics, and Cochrane risk of bias domains. We analyzed data using logistic regression and Chi-square statistics. Sequence generation was assessed to be inadequate (at unclear or high risk of bias) in 68% (n = 367) of the trials, while allocation concealment was inadequate in the majority of trials (n = 464; 85.9%). Blinding of participants and blinding of the outcome assessment were judged to be inadequate in 28.5% (n = 154) and 40.5% (n = 219) of the trials, respectively. A sample size calculation before the initiation of the study was not performed/reported in 79.1% (n = 427) of the trials, while the sample size was assessed as adequate in only 17.6% (n = 95) of the trials. Two thirds of the trials were not described as double blinded (n = 358; 66.3%), while the method of blinding was appropriate in 53% (n = 286) of the trials. We identified a significant decrease over time (1955-2013) in the proportion of trials assessed as having inadequately addressed methodological quality items (P < 0.05) in 30 out of the 40 quality criteria, or as being inadequate (at high or unclear risk of bias) in five domains of the Cochrane risk of bias tool: sequence generation, allocation concealment, incomplete outcome data, other sources of bias, and overall risk of bias. The risks of bias, risks of random errors, reporting quality, and methodological quality of randomized clinical trials of oral health interventions have improved over time; however, further efforts that contribute to the development of more stringent methodology and detailed reporting of trials are still needed.

Comparison of spatial association approaches for landscape mapping of soil organic carbon stocks

NASA Astrophysics Data System (ADS)

Miller, B. A.; Koszinski, S.; Wehrhan, M.; Sommer, M.

2015-03-01

The distribution of soil organic carbon (SOC) can be variable at small analysis scales, but consideration of its role in regional and global issues demands the mapping of large extents. There are many different strategies for mapping SOC, among which is to model the variables needed to calculate the SOC stock indirectly or to model the SOC stock directly. The purpose of this research is to compare direct and indirect approaches to mapping SOC stocks from rule-based, multiple linear regression models applied at the landscape scale via spatial association. The final products for both strategies are high-resolution maps of SOC stocks (kg m-2), covering an area of 122 km2, with accompanying maps of estimated error. For the direct modelling approach, the estimated error map was based on the internal error estimations from the model rules. For the indirect approach, the estimated error map was produced by spatially combining the error estimates of component models via standard error propagation equations. We compared these two strategies for mapping SOC stocks on the basis of the qualities of the resulting maps as well as the magnitude and distribution of the estimated error. The direct approach produced a map with less spatial variation than the map produced by the indirect approach. The increased spatial variation represented by the indirect approach improved R2 values for the topsoil and subsoil stocks. Although the indirect approach had a lower mean estimated error for the topsoil stock, the mean estimated error for the total SOC stock (topsoil + subsoil) was lower for the direct approach. For these reasons, we recommend the direct approach to modelling SOC stocks be considered a more conservative estimate of the SOC stocks' spatial distribution.

Comparison of spatial association approaches for landscape mapping of soil organic carbon stocks

NASA Astrophysics Data System (ADS)

Miller, B. A.; Koszinski, S.; Wehrhan, M.; Sommer, M.

2014-11-01

The distribution of soil organic carbon (SOC) can be variable at small analysis scales, but consideration of its role in regional and global issues demands the mapping of large extents. There are many different strategies for mapping SOC, among which are to model the variables needed to calculate the SOC stock indirectly or to model the SOC stock directly. The purpose of this research is to compare direct and indirect approaches to mapping SOC stocks from rule-based, multiple linear regression models applied at the landscape scale via spatial association. The final products for both strategies are high-resolution maps of SOC stocks (kg m-2), covering an area of 122 km2, with accompanying maps of estimated error. For the direct modelling approach, the estimated error map was based on the internal error estimations from the model rules. For the indirect approach, the estimated error map was produced by spatially combining the error estimates of component models via standard error propagation equations. We compared these two strategies for mapping SOC stocks on the basis of the qualities of the resulting maps as well as the magnitude and distribution of the estimated error. The direct approach produced a map with less spatial variation than the map produced by the indirect approach. The increased spatial variation represented by the indirect approach improved R2 values for the topsoil and subsoil stocks. Although the indirect approach had a lower mean estimated error for the topsoil stock, the mean estimated error for the total SOC stock (topsoil + subsoil) was lower for the direct approach. For these reasons, we recommend the direct approach to modelling SOC stocks be considered a more conservative estimate of the SOC stocks' spatial distribution.

A map overlay error model based on boundary geometry

USGS Publications Warehouse

Gaeuman, D.; Symanzik, J.; Schmidt, J.C.

2005-01-01

An error model for quantifying the magnitudes and variability of errors generated in the areas of polygons during spatial overlay of vector geographic information system layers is presented. Numerical simulation of polygon boundary displacements was used to propagate coordinate errors to spatial overlays. The model departs from most previous error models in that it incorporates spatial dependence of coordinate errors at the scale of the boundary segment. It can be readily adapted to match the scale of error-boundary interactions responsible for error generation on a given overlay. The area of error generated by overlay depends on the sinuosity of polygon boundaries, as well as the magnitude of the coordinate errors on the input layers. Asymmetry in boundary shape has relatively little effect on error generation. Overlay errors are affected by real differences in boundary positions on the input layers, as well as errors in the boundary positions. Real differences between input layers tend to compensate for much of the error generated by coordinate errors. Thus, the area of change measured on an overlay layer produced by the XOR overlay operation will be more accurate if the area of real change depicted on the overlay is large. The model presented here considers these interactions, making it especially useful for estimating errors studies of landscape change over time. ?? 2005 The Ohio State University.

Spatial heterogeneity of type I error for local cluster detection tests

PubMed Central

2014-01-01

Background Just as power, type I error of cluster detection tests (CDTs) should be spatially assessed. Indeed, CDTs’ type I error and power have both a spatial component as CDTs both detect and locate clusters. In the case of type I error, the spatial distribution of wrongly detected clusters (WDCs) can be particularly affected by edge effect. This simulation study aims to describe the spatial distribution of WDCs and to confirm and quantify the presence of edge effect. Methods A simulation of 40 000 datasets has been performed under the null hypothesis of risk homogeneity. The simulation design used realistic parameters from survey data on birth defects, and in particular, two baseline risks. The simulated datasets were analyzed using the Kulldorff’s spatial scan as a commonly used test whose behavior is otherwise well known. To describe the spatial distribution of type I error, we defined the participation rate for each spatial unit of the region. We used this indicator in a new statistical test proposed to confirm, as well as quantify, the edge effect. Results The predefined type I error of 5% was respected for both baseline risks. Results showed strong edge effect in participation rates, with a descending gradient from center to edge, and WDCs more often centrally situated. Conclusions In routine analysis of real data, clusters on the edge of the region should be carefully considered as they rarely occur when there is no cluster. Further work is needed to combine results from power studies with this work in order to optimize CDTs performance. PMID:24885343

Aspects of spatial and temporal aggregation in estimating regional carbon dioxide fluxes from temperate forest soils

NASA Technical Reports Server (NTRS)

Kicklighter, David W.; Melillo, Jerry M.; Peterjohn, William T.; Rastetter, Edward B.; Mcguire, A. David; Steudler, Paul A.; Aber, John D.

1994-01-01

We examine the influence of aggregation errors on developing estimates of regional soil-CO2 flux from temperate forests. We find daily soil-CO2 fluxes to be more sensitive to changes in soil temperatures (Q(sub 10) = 3.08) than air temperatures (Q(sub 10) = 1.99). The direct use of mean monthly air temperatures with a daily flux model underestimates regional fluxes by approximately 4%. Temporal aggregation error varies with spatial resolution. Overall, our calibrated modeling approach reduces spatial aggregation error by 9.3% and temporal aggregation error by 15.5%. After minimizing spatial and temporal aggregation errors, mature temperate forest soils are estimated to contribute 12.9 Pg C/yr to the atmosphere as carbon dioxide. Georeferenced model estimates agree well with annual soil-CO2 fluxes measured during chamber studies in mature temperate forest stands around the globe.

[Management of moderate to severe pediatric concealed penis in children by Devine's technique via incision between the penis and scrotum].

PubMed

Zhang, Xin-Sheng; Liu, Shi-Xiong; Xiang, Xue-Yan; Zhang, Wen-Gang; Tang, Da-Xing

2014-04-01

To search for a simple and effective surgical approach to the management of moderate to severe pediatric concealed penis in children. We used Devine's technique via incision between the penis and scrotum in the treatment of 68 cases of moderate to severe pediatric concealed penis. The patients were aged 3 -13 (mean 6.5) years, 30 with moderate and 38 with severe pediatric concealed penis. This strategy achieved good near- and long-term effects and satisfactory appearance of the penis, which was similar to that of circumcision. At 3 months after surgery, the penile length was 3 - 5.2 cm, averaging (2.35 +/- 0.35) cm. Devine's technique via incision between the penis and scrotum is a simple and effective surgical option for moderate to severe pediatric concealed penis in children.

Spatial sampling considerations of the CERES (Clouds and Earth Radiant Energy System) instrument

NASA Astrophysics Data System (ADS)

Smith, G. L.; Manalo-Smith, Natividdad; Priestley, Kory

2014-10-01

The CERES (Clouds and Earth Radiant Energy System) instrument is a scanning radiometer with three channels for measuring Earth radiation budget. At present CERES models are operating aboard the Terra, Aqua and Suomi/NPP spacecraft and flights of CERES instruments are planned for the JPSS-1 spacecraft and its successors. CERES scans from one limb of the Earth to the other and back. The footprint size grows with distance from nadir simply due to geometry so that the size of the smallest features which can be resolved from the data increases and spatial sampling errors increase with nadir angle. This paper presents an analysis of the effect of nadir angle on spatial sampling errors of the CERES instrument. The analysis performed in the Fourier domain. Spatial sampling errors are created by smoothing of features which are the size of the footprint and smaller, or blurring, and inadequate sampling, that causes aliasing errors. These spatial sampling errors are computed in terms of the system transfer function, which is the Fourier transform of the point response function, the spacing of data points and the spatial spectrum of the radiance field.

Concealable Stigmatized Identities and Psychological Well-Being

PubMed Central

Quinn, Diane M.; Earnshaw, Valerie A.

2013-01-01

Many people have concealable stigmatized identities: Identities that can be hidden from others and that are socially devalued and negatively stereotyped. Understanding how these concealable stigmatized identities affect psychological well-being is critical. We present our model of the components of concealable stigmatized identities including valenced content – internalized stigma, experienced discrimination, anticipated stigma, disclosure reactions, and counter-stereotypic/positive information – and magnitude – centrality and salience. Research has shown that negatively valenced content is related to increased psychological distress. However, smaller identity magnitude may buffer this distress. We review the research available and discuss important areas for future work. PMID:23730326

Entropy of Movement Outcome in Space-Time.

PubMed

Lai, Shih-Chiung; Hsieh, Tsung-Yu; Newell, Karl M

2015-07-01

Information entropy of the joint spatial and temporal (space-time) probability of discrete movement outcome was investigated in two experiments as a function of different movement strategies (space-time, space, and time instructional emphases), task goals (point-aiming and target-aiming) and movement speed-accuracy constraints. The variance of the movement spatial and temporal errors was reduced by instructional emphasis on the respective spatial or temporal dimension, but increased on the other dimension. The space-time entropy was lower in targetaiming task than the point aiming task but did not differ between instructional emphases. However, the joint probabilistic measure of spatial and temporal entropy showed that spatial error is traded for timing error in tasks with space-time criteria and that the pattern of movement error depends on the dimension of the measurement process. The unified entropy measure of movement outcome in space-time reveals a new relation for the speed-accuracy.

Precoded spatial multiplexing MIMO system with spatial component interleaver.

PubMed

Gao, Xiang; Wu, Zhanji

In this paper, the performance of precoded bit-interleaved coded modulation (BICM) spatial multiplexing multiple-input multiple-output (MIMO) system with spatial component interleaver is investigated. For the ideal precoded spatial multiplexing MIMO system with spatial component interleaver based on singular value decomposition (SVD) of the MIMO channel, the average pairwise error probability (PEP) of coded bits is derived. Based on the PEP analysis, the optimum spatial Q-component interleaver design criterion is provided to achieve the minimum error probability. For the limited feedback precoded proposed scheme with linear zero forcing (ZF) receiver, in order to minimize a bound on the average probability of a symbol vector error, a novel effective signal-to-noise ratio (SNR)-based precoding matrix selection criterion and a simplified criterion are proposed. Based on the average mutual information (AMI)-maximization criterion, the optimal constellation rotation angles are investigated. Simulation results indicate that the optimized spatial multiplexing MIMO system with spatial component interleaver can achieve significant performance advantages compared to the conventional spatial multiplexing MIMO system.

Diffraction analysis of sidelobe characteristics of optical elements with ripple error

NASA Astrophysics Data System (ADS)

Zhao, Lei; Luo, Yupeng; Bai, Jian; Zhou, Xiangdong; Du, Juan; Liu, Qun; Luo, Yujie

2018-03-01

The ripple errors of the lens lead to optical damage in high energy laser system. The analysis of sidelobe on the focal plane, caused by ripple error, provides a reference to evaluate the error and the imaging quality. In this paper, we analyze the diffraction characteristics of sidelobe of optical elements with ripple errors. First, we analyze the characteristics of ripple error and build relationship between ripple error and sidelobe. The sidelobe results from the diffraction of ripple errors. The ripple error tends to be periodic due to fabrication method on the optical surface. The simulated experiments are carried out based on angular spectrum method by characterizing ripple error as rotationally symmetric periodic structures. The influence of two major parameter of ripple including spatial frequency and peak-to-valley value to sidelobe is discussed. The results indicate that spatial frequency and peak-to-valley value both impact sidelobe at the image plane. The peak-tovalley value is the major factor to affect the energy proportion of the sidelobe. The spatial frequency is the major factor to affect the distribution of the sidelobe at the image plane.

Stereo sequence transmission via conventional transmission channel

NASA Astrophysics Data System (ADS)

Lee, Ho-Keun; Kim, Chul-Hwan; Han, Kyu-Phil; Ha, Yeong-Ho

2003-05-01

This paper proposes a new stereo sequence transmission technique using digital watermarking for compatibility with conventional 2D digital TV. We, generally, compress and transmit image sequence using temporal-spatial redundancy between stereo images. It is difficult for users with conventional digital TV to watch the transmitted 3D image sequence because many 3D image compression methods are different. To solve such a problem, in this paper, we perceive the concealment of new information of digital watermarking and conceal information of the other stereo image into three channels of the reference image. The main target of the technique presented is to let the people who have conventional DTV watch stereo movies at the same time. This goal is reached by considering the response of human eyes to color information and by using digital watermarking. To hide right images into left images effectively, bit-change in 3 color channels and disparity estimation according to the value of estimated disparity are performed. The proposed method assigns the displacement information of right image to each channel of YCbCr on DCT domain. Each LSB bit on YCbCr channels is changed according to the bits of disparity information. The performance of the presented methods is confirmed by several computer experiments.

Coincident disruptive coloration

PubMed Central

Cuthill, Innes C.; Székely, Aron

2008-01-01

Even if an animal matches its surroundings perfectly in colour and texture, any mismatch between the spatial phase of its pattern and that of the background, or shadow created by its three-dimensional relief, is potentially revealing. Nevertheless, for camouflage to be fully broken, the shape must be recognizable. Disruptive coloration acts against object recognition by the use of high-contrast internal colour boundaries to break up shape and form. As well as the general outline, characteristic features such as eyes and limbs must also be concealed; this can be achieved by having the colour patterns on different, but adjacent, body parts aligned to match each other (i.e. in phase). Such ‘coincident disruptive coloration’ ensures that there is no phase disjunction where body parts meet, and causes different sections of the body to blend perceptually. We tested this theory using field experiments with predation by wild birds on artificial moth-like targets, whose wings and (edible pastry) bodies had colour patterns that were variously coincident or not. We also carried out an experiment with humans searching for analogous targets on a computer screen. Both experiments show that coincident disruptive coloration is an effective mechanism for concealing an otherwise revealing body form. PMID:18990668

Geology and surface geochemistry of the Roosevelt Springs Known Geothermal Resource Area, Utah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lovell, J.S.; Meyer, W.T.; Atkinson, D.J.

1980-01-01

Available data on the Roosevelt area were synthesized to determine the spatial arrangement of the rocks, and the patterns of mass and energy flow within them. The resulting model lead to a new interpretation of the geothermal system, and provided ground truth for evaluating the application of soil geochemistry to exploration for concealed geothermal fields. Preliminary geochemical studies comparing the surface microlayer to conventional soil sampling methods indicated both practical and chemical advantages for the surface microlayer technique, which was particularly evident in the case of As, Sb and Cs. Subsequent multi-element analyses of surface microlayer samples collected over anmore » area of 100 square miles were processed to produce single element contour maps for 41 chemical parameters. Computer manipulation of the multi-element data using R-mode factor analysis provided the optimum method of interpretation of the surface microlayer data. A trace element association of As, Sb and Cs in the surface microlayer provided the best indication of the leakage of geothermal solutions to the surface, while regional mercury trends may reflect the presence of a mercury vapour anomaly above a concealed heat source.« less

Analysis of spatial correlation in predictive models of forest variables that use LiDAR auxiliary information

Treesearch

F. Mauro; Vicente J. Monleon; H. Temesgen; L.A. Ruiz

2017-01-01

Accounting for spatial correlation of LiDAR model errors can improve the precision of model-based estimators. To estimate spatial correlation, sample designs that provide close observations are needed, but their implementation might be prohibitively expensive. To quantify the gains obtained by accounting for the spatial correlation of model errors, we examined (

Keeping up appearances: the role of identity concealment in the workplace among adults with degenerative eye conditions and its relationship with wellbeing and career outcomes.

PubMed

Spiegel, Tali; De Bel, Vera; Steverink, Nardi

2016-01-01

This study aims to describe the interplay between the work trajectories and the passing patterns of individuals with degenerative eye conditions in different phases of their career, as well as the disease progression and the career and well-being outcomes associated with different works and passing trajectories. Qualitative interviews on the topic of work trajectories were conducted with 36 working or retired individuals with degenerative eye conditions. The "bigger picture" method was used to explore passing and concealment behavioral patterns, and their associations with various work trajectories. Five patterns of passing and concealment behavior in the workplace were identified and were linked with various work trajectories among visually impaired study participants: (1) no career adjustments, concealed condition throughout career; (2) revealed condition after adjusting career plans; (3) increasingly open about their condition over the course of their career; (4) engaged in career planning, always open about their condition; and (5) engaged in limited career planning, always open about their condition. Patterns characterized by less planning and more identity concealment were associated with more stress and lower levels of self-acceptance, while patterns characterized by more planning for vision deterioration and less passing behavior were associated with higher levels self-acceptance and fewer obstacles over the course of an individual's career. The study's findings can serve as a guide for health professionals. Many individuals with degenerative eye conditions try to conceal their identity as visually impaired in the professional setting. Different aspects of career outcomes (e.g. age of retirement) and wellbeing outcomes (e.g. self-acceptance and stress) associate with identity concealment patterns of individuals throughout their careers. Identifying concealment patterns will allow health professionals to tackle particular adverse outcomes and challenges associated with these patterns.

THz-wave parametric source and its imaging applications

NASA Astrophysics Data System (ADS)

Kawase, Kodo

2004-08-01

Widely tunable coherent terahertz (THz) wave generation has been demonstrated based on the parametric oscillation using MgO doped LiNbO3 crystal pumped by a Q-switched Nd:YAG laser. This method exhibits multiple advantages like wide tunability, coherency and compactness of its system. We have developed a novel basic technology for terahertz (THz) imaging, which allows detection and identification of chemicals by introducing the component spatial pattern analysis. The spatial distributions of the chemicals were obtained from terahertz multispectral transillumination images, using absorption spectra previously measured with a widely tunable THz-wave parametric oscillator. Further we have applied this technique to the detection and identification of illicit drugs concealed in envelopes. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

The Invisible Work of Closeting: A Qualitative Study About Strategies Used by Lesbian and Gay Persons to Conceal Their Sexual Orientation.

PubMed

Malterud, Kirsti; Bjorkman, Mari

2016-10-01

The last decades have offered substantial improvement regarding human rights for lesbian and gay (LG) persons. Yet LG persons are often in the closet, concealing their sexual orientation. We present a qualitative study based on 182 histories submitted from 161 LG individuals to a Web site. The aim was to explore experiences of closeting among LG persons in Norway. A broad range of strategies was used for closeting, even among individuals who generally considered themselves to be out of the closet. Concealment was enacted by blunt denial, clever avoidance, or subtle vagueness. Other strategies included changing or eliminating the pronoun or name of the partner in ongoing conversations. Context-dependent concealment, differentiating between persons, situations, or arenas, was repeatedly applied for security or convenience. We propose a shift from "being in the closet" to "situated concealment of sexual orientation."

Accounting for spatial correlation errors in the assimilation of GRACE into hydrological models through localization

NASA Astrophysics Data System (ADS)

Khaki, M.; Schumacher, M.; Forootan, E.; Kuhn, M.; Awange, J. L.; van Dijk, A. I. J. M.

2017-10-01

Assimilation of terrestrial water storage (TWS) information from the Gravity Recovery And Climate Experiment (GRACE) satellite mission can provide significant improvements in hydrological modelling. However, the rather coarse spatial resolution of GRACE TWS and its spatially correlated errors pose considerable challenges for achieving realistic assimilation results. Consequently, successful data assimilation depends on rigorous modelling of the full error covariance matrix of the GRACE TWS estimates, as well as realistic error behavior for hydrological model simulations. In this study, we assess the application of local analysis (LA) to maximize the contribution of GRACE TWS in hydrological data assimilation. For this, we assimilate GRACE TWS into the World-Wide Water Resources Assessment system (W3RA) over the Australian continent while applying LA and accounting for existing spatial correlations using the full error covariance matrix. GRACE TWS data is applied with different spatial resolutions including 1° to 5° grids, as well as basin averages. The ensemble-based sequential filtering technique of the Square Root Analysis (SQRA) is applied to assimilate TWS data into W3RA. For each spatial scale, the performance of the data assimilation is assessed through comparison with independent in-situ ground water and soil moisture observations. Overall, the results demonstrate that LA is able to stabilize the inversion process (within the implementation of the SQRA filter) leading to less errors for all spatial scales considered with an average RMSE improvement of 54% (e.g., 52.23 mm down to 26.80 mm) for all the cases with respect to groundwater in-situ measurements. Validating the assimilated results with groundwater observations indicates that LA leads to 13% better (in terms of RMSE) assimilation results compared to the cases with Gaussian errors assumptions. This highlights the great potential of LA and the use of the full error covariance matrix of GRACE TWS estimates for improved data assimilation results.

Forensic and homeland security applications of modern portable Raman spectroscopy.

PubMed

Izake, Emad L

2010-10-10

Modern detection and identification of chemical and biological hazards within the forensic and homeland security contexts may well require conducting the analysis in field while adapting a non-contact approach to the hazard. Technological achievements on both surface and resonance enhancement Raman scattering re-developed Raman spectroscopy to become the most adaptable spectroscopy technique for stand-off and non-contact analysis of hazards. On the other hand, spatially offset Raman spectroscopy proved to be very valuable for non-invasive chemical analysis of hazards concealed within non-transparent containers and packaging. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Improved segmentation of occluded and adjoining vehicles in traffic surveillance videos

NASA Astrophysics Data System (ADS)

Juneja, Medha; Grover, Priyanka

2013-12-01

Occlusion in image processing refers to concealment of any part of the object or the whole object from view of an observer. Real time videos captured by static cameras on roads often encounter overlapping and hence, occlusion of vehicles. Occlusion in traffic surveillance videos usually occurs when an object which is being tracked is hidden by another object. This makes it difficult for the object detection algorithms to distinguish all the vehicles efficiently. Also morphological operations tend to join the close proximity vehicles resulting in formation of a single bounding box around more than one vehicle. Such problems lead to errors in further video processing, like counting of vehicles in a video. The proposed system brings forward efficient moving object detection and tracking approach to reduce such errors. The paper uses successive frame subtraction technique for detection of moving objects. Further, this paper implements the watershed algorithm to segment the overlapped and adjoining vehicles. The segmentation results have been improved by the use of noise and morphological operations.

Spatial Assessment of Model Errors from Four Regression Techniques

Treesearch

Lianjun Zhang; Jeffrey H. Gove; Jeffrey H. Gove

2005-01-01

Fomst modelers have attempted to account for the spatial autocorrelations among trees in growth and yield models by applying alternative regression techniques such as linear mixed models (LMM), generalized additive models (GAM), and geographicalIy weighted regression (GWR). However, the model errors are commonly assessed using average errors across the entire study...

Concealed identification symbols and nondestructive determination of the identification symbols

DOEpatents

Nance, Thomas A.; Gibbs, Kenneth M.

2014-09-16

The concealing of one or more identification symbols into a target object and the subsequent determination or reading of such symbols through non-destructive testing is described. The symbols can be concealed in a manner so that they are not visible to the human eye and/or cannot be readily revealed to the human eye without damage or destruction of the target object. The identification symbols can be determined after concealment by e.g., the compilation of multiple X-ray images. As such, the present invention can also provide e.g., a deterrent to theft and the recovery of lost or stolen objects.

Fusion of radar and ultrasound sensors for concealed weapons detection

NASA Astrophysics Data System (ADS)

Felber, Franklin S.; Davis, Herbert T., III; Mallon, Charles E.; Wild, Norbert C.

1996-06-01

An integrated radar and ultrasound sensor, capable of remotely detecting and imaging concealed weapons, is being developed. A modified frequency-agile, mine-detection radar is intended to specify with high probability of detection at ranges of 1 to 10 m which individuals in a moving crowd may be concealing metallic or nonmetallic weapons. Within about 1 to 5 m, the active ultrasound sensor is intended to enable a user to identify a concealed weapon on a moving person with low false-detection rate, achieved through a real-time centimeter-resolution image of the weapon. The goal for sensor fusion is to have the radar acquire concealed weapons at long ranges and seamlessly hand over tracking data to the ultrasound sensor for high-resolution imaging on a video monitor. We have demonstrated centimeter-resolution ultrasound images of metallic and non-metallic weapons concealed on a human at ranges over 1 m. Processing of the ultrasound images includes filters for noise, frequency, brightness, and contrast. A frequency-agile radar has been developed by JAYCOR under the U.S. Army Advanced Mine Detection Radar Program. The signature of an armed person, detected by this radar, differs appreciably from that of the same person unarmed.

Re-assessing acalculia: Distinguishing spatial and purely arithmetical deficits in right-hemisphere damaged patients.

PubMed

Benavides-Varela, S; Piva, D; Burgio, F; Passarini, L; Rolma, G; Meneghello, F; Semenza, C

2017-03-01

Arithmetical deficits in right-hemisphere damaged patients have been traditionally considered secondary to visuo-spatial impairments, although the exact relationship between the two deficits has rarely been assessed. The present study implemented a voxelwise lesion analysis among 30 right-hemisphere damaged patients and a controlled, matched-sample, cross-sectional analysis with 35 cognitively normal controls regressing three composite cognitive measures on standardized numerical measures. The results showed that patients and controls significantly differ in Number comprehension, Transcoding, and Written operations, particularly subtractions and multiplications. The percentage of patients performing below the cutoffs ranged between 27% and 47% across these tasks. Spatial errors were associated with extensive lesions in fronto-temporo-parietal regions -which frequently lead to neglect- whereas pure arithmetical errors appeared related to more confined lesions in the right angular gyrus and its proximity. Stepwise regression models consistently revealed that spatial errors were primarily predicted by composite measures of visuo-spatial attention/neglect and representational abilities. Conversely, specific errors of arithmetic nature linked to representational abilities only. Crucially, the proportion of arithmetical errors (ranging from 65% to 100% across tasks) was higher than that of spatial ones. These findings thus suggest that unilateral right hemisphere lesions can directly affect core numerical/arithmetical processes, and that right-hemisphere acalculia is not only ascribable to visuo-spatial deficits as traditionally thought. Copyright © 2017 Elsevier Ltd. All rights reserved.

Accounting for substitution and spatial heterogeneity in a labelled choice experiment.

PubMed

Lizin, S; Brouwer, R; Liekens, I; Broeckx, S

2016-10-01

Many environmental valuation studies using stated preferences techniques are single-site studies that ignore essential spatial aspects, including possible substitution effects. In this paper substitution effects are captured explicitly in the design of a labelled choice experiment and the inclusion of different distance variables in the choice model specification. We test the effect of spatial heterogeneity on welfare estimates and transfer errors for minor and major river restoration works, and the transferability of river specific utility functions, accounting for key variables such as site visitation, spatial clustering and income. River specific utility functions appear to be transferable, resulting in low transfer errors. However, ignoring spatial heterogeneity increases transfer errors. Copyright © 2016 Elsevier Ltd. All rights reserved.

A new polishing process for large-aperture and high-precision aspheric surface

NASA Astrophysics Data System (ADS)

Nie, Xuqing; Li, Shengyi; Dai, Yifan; Song, Ci

2013-07-01

The high-precision aspheric surface is hard to be achieved due to the mid-spatial frequency error in the finishing step. The influence of mid-spatial frequency error is studied through the simulations and experiments. In this paper, a new polishing process based on magnetorheological finishing (MRF), smooth polishing (SP) and ion beam figuring (IBF) is proposed. A 400mm aperture parabolic surface is polished with this new process. The smooth polishing (SP) is applied after rough machining to control the MSF error. In the middle finishing step, most of low-spatial frequency error is removed by MRF rapidly, then the mid-spatial frequency error is restricted by SP, finally ion beam figuring is used to finish the surface. The surface accuracy is improved from the initial 37.691nm (rms, 95% aperture) to the final 4.195nm. The results show that the new polishing process is effective to manufacture large-aperture and high-precision aspheric surface.

Deterministic error correction for nonlocal spatial-polarization hyperentanglement

PubMed Central

Li, Tao; Wang, Guan-Yu; Deng, Fu-Guo; Long, Gui-Lu

2016-01-01

Hyperentanglement is an effective quantum source for quantum communication network due to its high capacity, low loss rate, and its unusual character in teleportation of quantum particle fully. Here we present a deterministic error-correction scheme for nonlocal spatial-polarization hyperentangled photon pairs over collective-noise channels. In our scheme, the spatial-polarization hyperentanglement is first encoded into a spatial-defined time-bin entanglement with identical polarization before it is transmitted over collective-noise channels, which leads to the error rejection of the spatial entanglement during the transmission. The polarization noise affecting the polarization entanglement can be corrected with a proper one-step decoding procedure. The two parties in quantum communication can, in principle, obtain a nonlocal maximally entangled spatial-polarization hyperentanglement in a deterministic way, which makes our protocol more convenient than others in long-distance quantum communication. PMID:26861681

Deterministic error correction for nonlocal spatial-polarization hyperentanglement.

PubMed

Li, Tao; Wang, Guan-Yu; Deng, Fu-Guo; Long, Gui-Lu

2016-02-10

Hyperentanglement is an effective quantum source for quantum communication network due to its high capacity, low loss rate, and its unusual character in teleportation of quantum particle fully. Here we present a deterministic error-correction scheme for nonlocal spatial-polarization hyperentangled photon pairs over collective-noise channels. In our scheme, the spatial-polarization hyperentanglement is first encoded into a spatial-defined time-bin entanglement with identical polarization before it is transmitted over collective-noise channels, which leads to the error rejection of the spatial entanglement during the transmission. The polarization noise affecting the polarization entanglement can be corrected with a proper one-step decoding procedure. The two parties in quantum communication can, in principle, obtain a nonlocal maximally entangled spatial-polarization hyperentanglement in a deterministic way, which makes our protocol more convenient than others in long-distance quantum communication.

The association between concealing emotions at work and medical utilization in Korea.

PubMed

Seok, Hongdeok; Yoon, Jin-Ha; Lee, Wanhyung; Lee, June-Hee; Jung, Pil Kyun; Kim, Inah; Won, Jong-Uk; Roh, Jaehoon

2014-01-01

We aimed to investigate the association between concealing emotions at work and medical utilization. Data from the 2007-2009 4th Korea National Health and Nutrition Examination Survey (KNHANES IV) was used, 7,094 participants (3,837 males, 3,257 females) aged between 20 and 54 who were economically active and completed all necessary questionnaire items were included. Odds ratios (ORs) and 95% confidence intervals (95% CI) for differences in hospitalization, outpatient visits, and pharmaceutical drug use between those who concealed their emotions and those who did not were investigated using logistic regression models with and without gender stratification. Among those who concealed their emotions (n = 2,763), 47.4% were females, and 50.1% had chronic disease. In addition, 9.7% of the concealing emotions group had been hospitalized within the last year, 24.8% had been outpatients in the last two weeks, and 28.3% had used pharmaceutical drugs in the last two weeks. All ORs represent the odds of belonging to the concealing emotions group over the non-concealing emotions group. After adjustment for individual, occupational, socioeconomic and disease factors, the adjusted ORs (95% CI) in hospitalization are 1.29 (1.08 ~ 1.53) in the total population, 1.25 (0.98 ~ 1.60) in males and 1.30 (1.02 ~ 1.66) in females, in outpatient visits are 1.15 (1.02 ~ 1.29) in the total population, 1.05 (0.88 ~ 1.24) in males and 1.25 (1.06 ~ 1.47) in females and in pharmaceutical drug use are 1.12 (1.01 ~ 1.25) in the total population, 1.08 (0.92 ~ 1.27) in males and 1.14 (0.98 ~ 1.33) in females. Those who concealed their emotions at work were more likely to use medical services. Moreover, the health effects of concealing emotions at work might be more detrimental in women than in men.

Concealment of type 1 diabetes at work in Finland: a mixed-method study

PubMed Central

Munir, Fehmidah; Moilanen, Leena; Räsänen, Kimmo; Hänninen, Vilma

2018-01-01

Objectives To explore the possible reasons for concealing type 1 diabetes (T1D) at work. Methods The main set of data came from a cross-sectional survey (response rate 49.3%), the participants of which were 688 wage earners with T1D. Concealment of T1D was measured by asking respondents have they ever during their working career hidden their diabetes from their (A) colleagues and (B) line manager. Furthermore, semistructured interviews (n=20) were conducted to obtain deeper understanding. Questionnaire data were analysed using logistic regression analyses and qualitative interviews with inductive thematic analysis. Results About 30% of wage earners with T1D had concealed their condition during their working career from their colleagues and almost 20% from their line manager. Individuals aged 18–44 years age were more likely to conceal their T1D from their colleagues than older workers during their working career. Not disclosing T1D to the extended family (OR 5.24 (95% CI 2.06 to 13.35)), feeling an outsider at work (OR 2.47 (95% CI 1.58 to 3.84)), being embarrassed by receiving special attention at work (OR 1.99 (95% CI 1.33 to 2.96)) and neglecting treatment at work (OR 1.59 (95% CI 1.01 to 2.48)) were all associated with concealment of T1D from colleagues. The youngest age group of 18–24 years were more likely to conceal their T1D from their line managers than the older age groups during their working career. Not disclosing T1D to the extended family (OR 4.41 (95% CI 1.72 to 11.32)), feeling like an outsider at work (OR 2.51 (1.52 to 4.14)) and being embarrassed by receiving special attention at work (OR 1.81 (95% CI 1.13 to 2.91)) were associated with concealment of T1D from line managers. From the interviews, five main themes related to concealment emerged, expressing fears related to the consequences of telling: (1) being perceived as weak, (2) job discrimination, (3) unwanted attention, (4) being seen as a person who uses their T1D for seeking advantages and (5) losing privacy. Conclusions A considerable proportion of wage earners with T1D are concealing their diagnosis often because of feelings associated with stigma. Both overemphasis and underestimation of T1D at work by the colleagues or line manager may lead to concealing T1D and may thus be harmful to self-management of T1D. The obstacles in disclosing T1D might be diminished by giving adequate information at the workplace about the condition and its significance. PMID:29331976

A Concealed Barcode Identification System Using Terahertz Time-domain Spectroscopy

NASA Astrophysics Data System (ADS)

Guan, Yu; Yamamoto, Manabu; Kitazawa, Toshiyuki; Tripathi, Saroj R.; Takeya, Kei; Kawase, Kodo

2015-03-01

We present a concealed terahertz barcode/chipless tag to achieve remote identification through an obstructing material using terahertz radiation. We show scanned terahertz reflection spectral images of barcodes concealed by a thick obstacle. A concealed and double- side printed terahertz barcode structure is proposed, and we demonstrate that our design has better performance in definition than a single-side printed barcode using terahertz time-domain spectroscopy. This technique combines the benefits of a chipless tag to read encoded information covered by an optically opaque material with low cost and a simple fabrication process. Simulations are also described, along with an explanation of the principle of the terahertz barcode identification system.

Drug concealment in custody deaths--two cases.

PubMed

Busuttil, A

1994-06-01

Internal concealment of drugs of abuse is a well established method of transporting such substances to avoid detection while they are being smuggled across international frontier lines.(1,2) The same method has been used by dealers and 'pushers' in between purchases on their selling rounds to avoid detection by the police. These methods of hiding drugs may be used by persons taken into short-term custody, in their belief that potential withdrawal effects would thus be avoided by continued availability of their drugs. Two cases are reported in which such concealment was discovered at autopsy after death had occurred while in police custody. In one case the drug concealed was dihydrocodeine and was directly responsible for the death.

Out and healthy: Being more "out" about a concealable stigmatized identity may boost the health benefits of social support.

PubMed

Weisz, Bradley M; Quinn, Diane M; Williams, Michelle K

2016-12-01

This research examined whether the relationship between perceived social support and health would be moderated by level of outness for people living with different concealable stigmatized identities (mental illness, substance abuse, domestic violence, rape, or childhood abuse). A total of 394 people living with a concealable stigmatized identity completed a survey. Consistent with hypotheses, at high levels of outness, social support predicted better health; at low levels of outness, social support was less predictive of health. People concealing a stigmatized identity may only be able to reap the health benefits of social support if they are "out" about the stigmatized identity. © The Author(s) 2015.

Post-parturition habitat selection by elk calves and adult female elk in New Mexico

USGS Publications Warehouse

Pitman, James W.; Cain, James W.; Liley, Stewart; Gould, William R.; Quintana, Nichole T.; Ballard, Warren

2014-01-01

Neonatal survival and juvenile recruitment are crucial to maintaining viable elk (Cervus elaphus) populations. Neonate survival is known to be influenced by many factors, including bed-site selection. Although neonates select the actual bed-site location, they must do so within the larger calf-rearing area selected by the mother. As calves age, habitat selection should change to meet the changing needs of the growing calf. Our main objectives were to characterize habitat selection at 2 spatial scales and in areas with different predator assemblages in New Mexico. We evaluated bed-site selection by calves and calf-rearing area selection by adult females. We captured 108 elk calves by hand and fitted them with ear tag transmitters in two areas in New Mexico: the Valle Vidal and Blue Range Wolf Recovery Area. In both study areas, we found that concealing cover structure and distance to that cover influenced bed-site selection of young calves (i.e., <2 weeks of age). Older calves (i.e., 3–10 weeks of age) still selected areas in relation to distance to cover, but also preferred areas with higher visibility. At the larger spatial scale of calf-rearing habitat selection by the adult female, concealing cover (e.g., rocks, shrubs, and logs) and other variables important to the hiding calves were still in the most supported models, but selection was also influenced by forage availability and indices of forage quality. Studies that seek to obtain insight into microhabitat selection of ungulate neonates should consider selection by the neonate and selection by the adult female, changes in selection as neonates age, and potential selection differences in areas of differing predation risk. By considering these influences together and at multiple scales, studies can achieve a broader understanding of neonatal ungulate habitat requirements. 

Concealed wire tracing apparatus

DOEpatents

Kronberg, J.W.

1994-05-31

An apparatus and method that combines a signal generator and a passive signal receiver to detect and record the path of partially or completely concealed electrical wiring without disturbing the concealing surface is disclosed. The signal generator applies a series of electrical pulses to the selected wiring of interest. The applied pulses create a magnetic field about the wiring that can be detected by a coil contained within the signal receiver. An audible output connected to the receiver and driven by the coil reflects the receivers position with respect to the wiring. The receivers audible signal is strongest when the receiver is directly above the wiring and the long axis of the receivers coil is parallel to the wiring. A marking means is mounted on the receiver to mark the location of the wiring as the receiver is directed over the wiring's concealing surface. Numerous marks made on various locations of the concealing surface will trace the path of the wiring of interest. 4 figs.

Associations Between Secret-Keeping and Quality of Life in Older Adults.

PubMed

Maas, Joyce; Wismeijer, Andreas A J; Van Assen, Marcel A L M

2018-01-01

This study examined the effects of secrecy on quality of life in a sample consisting of older adults (>50 years; N = 301). Three key components of secrecy were examined with the Tilburg Secrecy Scale-25 (TSS25; possession of a secret, self-concealment, and cognitive preoccupation). The TSS25 distinguishes between the tendency to conceal personal information (self-concealment) and the tendency to worry or ruminate about the secret (cognitive preoccupation), thereby enabling investigation of the effects of secrecy on quality of life in detail. Confirming previous findings in younger samples, we found a positive effect of possession of a secret on quality of life, after controlling for both TSS25's self-concealment and cognitive preoccupation. This suggests that keeping secrets may have a positive association with quality of life in older adults as well, as long as they do not have the tendency to self-conceal and are not cognitively preoccupied with their secret.

Geochemical Data for Samples Collected in 2008 Near the Concealed Pebble Porphyry Cu-Au-Mo Deposit, Southwest Alaska

USGS Publications Warehouse

Fey, David L.; Granitto, Matthew; Giles, Stuart A.; Smith, Steven M.; Eppinger, Robert G.; Kelley, Karen D.

2009-01-01

In the summer of 2007, the U.S. Geological Survey (USGS) began an exploration geochemical research study over the Pebble porphyry copper-gold-molybdenum deposit. This report presents the analytical data collected in 2008. The Pebble deposit is world class in size, and is almost entirely concealed by tundra, glacial deposits, and post-Cretaceous volcanic rocks. The Pebble deposit was chosen for this study because it is concealed by surficial cover rocks, is relatively undisturbed (except for exploration company drill holes), is a large mineral system, and is fairly well-constrained at depth by the drill hole geology and geochemistry. The goals of this study are to 1) determine whether the concealed deposit can be detected with surface samples, 2) better understand the processes of metal migration from the deposit to the surface, and 3) test and develop methods for assessing mineral resources in similar concealed terrains. The analytical data are presented as an integrated Microsoft Access 2003 database and as separate Excel files.

Impact of Spatial Soil and Climate Input Data Aggregation on Regional Yield Simulations

PubMed Central

Hoffmann, Holger; Zhao, Gang; Asseng, Senthold; Bindi, Marco; Biernath, Christian; Constantin, Julie; Coucheney, Elsa; Dechow, Rene; Doro, Luca; Eckersten, Henrik; Gaiser, Thomas; Grosz, Balázs; Heinlein, Florian; Kassie, Belay T.; Kersebaum, Kurt-Christian; Klein, Christian; Kuhnert, Matthias; Lewan, Elisabet; Moriondo, Marco; Nendel, Claas; Priesack, Eckart; Raynal, Helene; Roggero, Pier P.; Rötter, Reimund P.; Siebert, Stefan; Specka, Xenia; Tao, Fulu; Teixeira, Edmar; Trombi, Giacomo; Wallach, Daniel; Weihermüller, Lutz; Yeluripati, Jagadeesh; Ewert, Frank

2016-01-01

We show the error in water-limited yields simulated by crop models which is associated with spatially aggregated soil and climate input data. Crop simulations at large scales (regional, national, continental) frequently use input data of low resolution. Therefore, climate and soil data are often generated via averaging and sampling by area majority. This may bias simulated yields at large scales, varying largely across models. Thus, we evaluated the error associated with spatially aggregated soil and climate data for 14 crop models. Yields of winter wheat and silage maize were simulated under water-limited production conditions. We calculated this error from crop yields simulated at spatial resolutions from 1 to 100 km for the state of North Rhine-Westphalia, Germany. Most models showed yields biased by <15% when aggregating only soil data. The relative mean absolute error (rMAE) of most models using aggregated soil data was in the range or larger than the inter-annual or inter-model variability in yields. This error increased further when both climate and soil data were aggregated. Distinct error patterns indicate that the rMAE may be estimated from few soil variables. Illustrating the range of these aggregation effects across models, this study is a first step towards an ex-ante assessment of aggregation errors in large-scale simulations. PMID:27055028

Impact of Spatial Soil and Climate Input Data Aggregation on Regional Yield Simulations.

PubMed

Hoffmann, Holger; Zhao, Gang; Asseng, Senthold; Bindi, Marco; Biernath, Christian; Constantin, Julie; Coucheney, Elsa; Dechow, Rene; Doro, Luca; Eckersten, Henrik; Gaiser, Thomas; Grosz, Balázs; Heinlein, Florian; Kassie, Belay T; Kersebaum, Kurt-Christian; Klein, Christian; Kuhnert, Matthias; Lewan, Elisabet; Moriondo, Marco; Nendel, Claas; Priesack, Eckart; Raynal, Helene; Roggero, Pier P; Rötter, Reimund P; Siebert, Stefan; Specka, Xenia; Tao, Fulu; Teixeira, Edmar; Trombi, Giacomo; Wallach, Daniel; Weihermüller, Lutz; Yeluripati, Jagadeesh; Ewert, Frank

2016-01-01

We show the error in water-limited yields simulated by crop models which is associated with spatially aggregated soil and climate input data. Crop simulations at large scales (regional, national, continental) frequently use input data of low resolution. Therefore, climate and soil data are often generated via averaging and sampling by area majority. This may bias simulated yields at large scales, varying largely across models. Thus, we evaluated the error associated with spatially aggregated soil and climate data for 14 crop models. Yields of winter wheat and silage maize were simulated under water-limited production conditions. We calculated this error from crop yields simulated at spatial resolutions from 1 to 100 km for the state of North Rhine-Westphalia, Germany. Most models showed yields biased by <15% when aggregating only soil data. The relative mean absolute error (rMAE) of most models using aggregated soil data was in the range or larger than the inter-annual or inter-model variability in yields. This error increased further when both climate and soil data were aggregated. Distinct error patterns indicate that the rMAE may be estimated from few soil variables. Illustrating the range of these aggregation effects across models, this study is a first step towards an ex-ante assessment of aggregation errors in large-scale simulations.

Experimental power spectral density analysis for mid- to high-spatial frequency surface error control.

PubMed

Hoyo, Javier Del; Choi, Heejoo; Burge, James H; Kim, Geon-Hee; Kim, Dae Wook

2017-06-20

The control of surface errors as a function of spatial frequency is critical during the fabrication of modern optical systems. A large-scale surface figure error is controlled by a guided removal process, such as computer-controlled optical surfacing. Smaller-scale surface errors are controlled by polishing process parameters. Surface errors of only a few millimeters may degrade the performance of an optical system, causing background noise from scattered light and reducing imaging contrast for large optical systems. Conventionally, the microsurface roughness is often given by the root mean square at a high spatial frequency range, with errors within a 0.5×0.5  mm local surface map with 500×500 pixels. This surface specification is not adequate to fully describe the characteristics for advanced optical systems. The process for controlling and minimizing mid- to high-spatial frequency surface errors with periods of up to ∼2-3  mm was investigated for many optical fabrication conditions using the measured surface power spectral density (PSD) of a finished Zerodur optical surface. Then, the surface PSD was systematically related to various fabrication process parameters, such as the grinding methods, polishing interface materials, and polishing compounds. The retraceable experimental polishing conditions and processes used to produce an optimal optical surface PSD are presented.

Spatial abstraction for autonomous robot navigation.

PubMed

Epstein, Susan L; Aroor, Anoop; Evanusa, Matthew; Sklar, Elizabeth I; Parsons, Simon

2015-09-01

Optimal navigation for a simulated robot relies on a detailed map and explicit path planning, an approach problematic for real-world robots that are subject to noise and error. This paper reports on autonomous robots that rely on local spatial perception, learning, and commonsense rationales instead. Despite realistic actuator error, learned spatial abstractions form a model that supports effective travel.

Detection of a concealed object

DOEpatents

Keller, Paul E [Richland, WA; Hall, Thomas E [Kennewick, WA; McMakin, Douglas L [Richland, WA

2010-11-16

Disclosed are systems, methods, devices, and apparatus to determine if a clothed individual is carrying a suspicious, concealed object. This determination includes establishing data corresponding to an image of the individual through interrogation with electromagnetic radiation in the 200 MHz to 1 THz range. In one form, image data corresponding to intensity of reflected radiation and differential depth of the reflecting surface is received and processed to detect the suspicious, concealed object.

Detection of a concealed object

DOEpatents

Keller, Paul E [Richland, WA; Hall, Thomas E [Kennewick, WA; McMakin, Douglas L [Richland, WA

2008-04-29

Disclosed are systems, methods, devices, and apparatus to determine if a clothed individual is carrying a suspicious, concealed object. This determination includes establishing data corresponding to an image of the individual through interrogation with electromagnetic radiation in the 200 MHz to 1 THz range. In one form, image data corresponding to intensity of reflected radiation and differential depth of the reflecting surface is received and processed to detect the suspicious, concealed object.

Impact of exposure measurement error in air pollution epidemiology: effect of error type in time-series studies.

PubMed

Goldman, Gretchen T; Mulholland, James A; Russell, Armistead G; Strickland, Matthew J; Klein, Mitchel; Waller, Lance A; Tolbert, Paige E

2011-06-22

Two distinctly different types of measurement error are Berkson and classical. Impacts of measurement error in epidemiologic studies of ambient air pollution are expected to depend on error type. We characterize measurement error due to instrument imprecision and spatial variability as multiplicative (i.e. additive on the log scale) and model it over a range of error types to assess impacts on risk ratio estimates both on a per measurement unit basis and on a per interquartile range (IQR) basis in a time-series study in Atlanta. Daily measures of twelve ambient air pollutants were analyzed: NO2, NOx, O3, SO2, CO, PM10 mass, PM2.5 mass, and PM2.5 components sulfate, nitrate, ammonium, elemental carbon and organic carbon. Semivariogram analysis was applied to assess spatial variability. Error due to this spatial variability was added to a reference pollutant time-series on the log scale using Monte Carlo simulations. Each of these time-series was exponentiated and introduced to a Poisson generalized linear model of cardiovascular disease emergency department visits. Measurement error resulted in reduced statistical significance for the risk ratio estimates for all amounts (corresponding to different pollutants) and types of error. When modelled as classical-type error, risk ratios were attenuated, particularly for primary air pollutants, with average attenuation in risk ratios on a per unit of measurement basis ranging from 18% to 92% and on an IQR basis ranging from 18% to 86%. When modelled as Berkson-type error, risk ratios per unit of measurement were biased away from the null hypothesis by 2% to 31%, whereas risk ratios per IQR were attenuated (i.e. biased toward the null) by 5% to 34%. For CO modelled error amount, a range of error types were simulated and effects on risk ratio bias and significance were observed. For multiplicative error, both the amount and type of measurement error impact health effect estimates in air pollution epidemiology. By modelling instrument imprecision and spatial variability as different error types, we estimate direction and magnitude of the effects of error over a range of error types.

Documentation of procedures for textural/spatial pattern recognition techniques

NASA Technical Reports Server (NTRS)

Haralick, R. M.; Bryant, W. F.

1976-01-01

A C-130 aircraft was flown over the Sam Houston National Forest on March 21, 1973 at 10,000 feet altitude to collect multispectral scanner (MSS) data. Existing textural and spatial automatic processing techniques were used to classify the MSS imagery into specified timber categories. Several classification experiments were performed on this data using features selected from the spectral bands and a textural transform band. The results indicate that (1) spatial post-processing a classified image can cut the classification error to 1/2 or 1/3 of its initial value, (2) spatial post-processing the classified image using combined spectral and textural features produces a resulting image with less error than post-processing a classified image using only spectral features and (3) classification without spatial post processing using the combined spectral textural features tends to produce about the same error rate as a classification without spatial post processing using only spectral features.

THz-wave parametric sources and imaging applications

NASA Astrophysics Data System (ADS)

Kawase, Kodo

2004-12-01

We have studied the generation of terahertz (THz) waves by optical parametric processes based on laser light scattering from the polariton mode of nonlinear crystals. Using parametric oscillation of MgO-doped LiNbO3 crystal pumped by a nano-second Q-switched Nd:YAG laser, we have realized a widely tunable coherent THz-wave sources with a simple configuration. We have also developed a novel basic technology for THz imaging, which allows detection and identification of chemicals by introducing the component spatial pattern analysis. The spatial distributions of the chemicals were obtained from terahertz multispectral trasillumination images, using absorption spectra previously measured with a widely tunable THz-wave parametric oscillator. Further we have applied this technique to the detection and identification of illicit drugs concealed in envelopes. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

Functional analysis of concealment: a novel application of prospect and refuge theory.

PubMed

Singh, Punya; Ellard, Colin G

2012-09-01

According to prospect-refuge theory, humans prefer environments that afford protection from threat (refuge), but also provide large fields of view (prospect). Prospect-refuge theory in the past has traditionally only been applied to humans, but many of the same contingencies governing spatial preference ought to also hold true in animals. The focus of this study was to examine if this phenomena also occurs in animals. Gerbils were placed in an arena containing three dome shaped refuges that varied in prospect-refuge levels. A simulated predator was released during the trial to examine how contextual factors may influence the degree of prospect and refuge preferred. The results indicate a preference for the enclosed refuge at stimulus onset even though this was not reflective of what happened prior to predator release. The results suggest spatial preferences in animals are influenced by prospect-refuge considerations in certain contexts. Copyright © 2012 Elsevier B.V. All rights reserved.

Relationship authenticity partially mediates the effects of attachment on relationship satisfaction.

PubMed

Rasco, Danney; Warner, Rebecca M

2017-01-01

Individuals with anxious and avoidant attachment tend to experience less satisfaction in their relationships. Past research suggests the negative effects of attachment on relationship satisfaction may be partially mediated by self-disclosure and self-concealment; the present study evaluated relationship authenticity as a potential additional mediator. Confirmatory factor analysis indicated that relationship authenticity is distinct from self-disclosure and self-concealment. Relationship authenticity predicted additional variance in relationship satisfaction controlling for attachment, self-disclosure, and self-concealment. The results were consistent with relationship authenticity, along with self-disclosure and self-concealment, partially mediating the effects of attachment on relationship satisfaction. These findings suggest that relationship authenticity may play a unique role in understanding how attachment influences relationship satisfaction. Theoretical and clinical implications are discussed.

Spatial measurement error and correction by spatial SIMEX in linear regression models when using predicted air pollution exposures.

PubMed

Alexeeff, Stacey E; Carroll, Raymond J; Coull, Brent

2016-04-01

Spatial modeling of air pollution exposures is widespread in air pollution epidemiology research as a way to improve exposure assessment. However, there are key sources of exposure model uncertainty when air pollution is modeled, including estimation error and model misspecification. We examine the use of predicted air pollution levels in linear health effect models under a measurement error framework. For the prediction of air pollution exposures, we consider a universal Kriging framework, which may include land-use regression terms in the mean function and a spatial covariance structure for the residuals. We derive the bias induced by estimation error and by model misspecification in the exposure model, and we find that a misspecified exposure model can induce asymptotic bias in the effect estimate of air pollution on health. We propose a new spatial simulation extrapolation (SIMEX) procedure, and we demonstrate that the procedure has good performance in correcting this asymptotic bias. We illustrate spatial SIMEX in a study of air pollution and birthweight in Massachusetts. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The role of visual spatial attention in adult developmental dyslexia.

PubMed

Collis, Nathan L; Kohnen, Saskia; Kinoshita, Sachiko

2013-01-01

The present study investigated the nature of visual spatial attention deficits in adults with developmental dyslexia, using a partial report task with five-letter, digit, and symbol strings. Participants responded by a manual key press to one of nine alternatives, which included other characters in the string, allowing an assessment of position errors as well as intrusion errors. The results showed that the dyslexic adults performed significantly worse than age-matched controls with letter and digit strings but not with symbol strings. Both groups produced W-shaped serial position functions with letter and digit strings. The dyslexics' deficits with letter string stimuli were limited to position errors, specifically at the string-interior positions 2 and 4. These errors correlated with letter transposition reading errors (e.g., reading slat as "salt"), but not with the Rapid Automatized Naming (RAN) task. Overall, these results suggest that the dyslexic adults have a visual spatial attention deficit; however, the deficit does not reflect a reduced span in visual-spatial attention, but a deficit in processing a string of letters in parallel, probably due to difficulty in the coding of letter position.

Soil pH Errors Propagation from Measurements to Spatial Predictions - Cost Benefit Analysis and Risk Assessment Implications for Practitioners and Modelers

NASA Astrophysics Data System (ADS)

Owens, P. R.; Libohova, Z.; Seybold, C. A.; Wills, S. A.; Peaslee, S.; Beaudette, D.; Lindbo, D. L.

2017-12-01

The measurement errors and spatial prediction uncertainties of soil properties in the modeling community are usually assessed against measured values when available. However, of equal importance is the assessment of errors and uncertainty impacts on cost benefit analysis and risk assessments. Soil pH was selected as one of the most commonly measured soil properties used for liming recommendations. The objective of this study was to assess the error size from different sources and their implications with respect to management decisions. Error sources include measurement methods, laboratory sources, pedotransfer functions, database transections, spatial aggregations, etc. Several databases of measured and predicted soil pH were used for this study including the United States National Cooperative Soil Survey Characterization Database (NCSS-SCDB), the US Soil Survey Geographic (SSURGO) Database. The distribution of errors among different sources from measurement methods to spatial aggregation showed a wide range of values. The greatest RMSE of 0.79 pH units was from spatial aggregation (SSURGO vs Kriging), while the measurement methods had the lowest RMSE of 0.06 pH units. Assuming the order of data acquisition based on the transaction distance i.e. from measurement method to spatial aggregation the RMSE increased from 0.06 to 0.8 pH units suggesting an "error propagation". This has major implications for practitioners and modeling community. Most soil liming rate recommendations are based on 0.1 pH unit increments, while the desired soil pH level increments are based on 0.4 to 0.5 pH units. Thus, even when the measured and desired target soil pH are the same most guidelines recommend 1 ton ha-1 lime, which translates in 111 ha-1 that the farmer has to factor in the cost-benefit analysis. However, this analysis need to be based on uncertainty predictions (0.5-1.0 pH units) rather than measurement errors (0.1 pH units) which would translate in 555-1,111 investment that need to be assessed against the risk. The modeling community can benefit from such analysis, however, error size and spatial distribution for global and regional predictions need to be assessed against the variability of other drivers and impact on management decisions.

Design Considerations of Polishing Lap for Computer-Controlled Cylindrical Polishing Process

NASA Technical Reports Server (NTRS)

Khan, Gufran S.; Gubarev, Mikhail; Arnold, William; Ramsey, Brian D.

2009-01-01

This paper establishes a relationship between the polishing process parameters and the generation of mid spatial-frequency error. The consideration of the polishing lap design to optimize the process in order to keep residual errors to a minimum and optimization of the process (speeds, stroke, etc.) and to keep the residual mid spatial-frequency error to a minimum, is also presented.

Noninvasive deep Raman detection with 2D correlation analysis

NASA Astrophysics Data System (ADS)

Kim, Hyung Min; Park, Hyo Sun; Cho, Youngho; Jin, Seung Min; Lee, Kang Taek; Jung, Young Mee; Suh, Yung Doug

2014-07-01

The detection of poisonous chemicals enclosed in daily necessaries is prerequisite essential for homeland security with the increasing threat of terrorism. For the detection of toxic chemicals, we combined a sensitive deep Raman spectroscopic method with 2D correlation analysis. We obtained the Raman spectra from concealed chemicals employing spatially offset Raman spectroscopy in which incident line-shaped light experiences multiple scatterings before being delivered to inner component and yielding deep Raman signal. Furthermore, we restored the pure Raman spectrum of each component using 2D correlation spectroscopic analysis with chemical inspection. Using this method, we could elucidate subsurface component under thick powder and packed contents in a bottle.

Prospects for quantum cascade lasers as transmitters and local oscillators in coherent terahertz transmitter/receiver systems

NASA Astrophysics Data System (ADS)

Waldman, Jerry; Danylov, Andriy A.; Goyette, Thomas M.; Coulombe, Michael J.; Giles, Robert H.; Gatesman, Andrew J.; Goodhue, William D.; Li, Jin; Linden, Kurt J.; Nixon, William E.

2009-02-01

Coherent terahertz radar systems, using CO2 laser-pumped molecular lasers have been used during the past decade for radar scale modeling applications, as well as proof-of-principle demonstrations of remote detection of concealed weapons. The presentation will consider the potential for replacement of molecular laser sources by quantum cascade lasers. While the temporal and spatial characteristics of current THz QCLs limit their applicability, rapid progress is being made in resolving these issues. Specifications for satisfying the requirements of coherent short-range THz radars will be reviewed and the feasibility of incorporating existing QCL devices into such systems will be described.

A review of visual perception mechanisms that regulate rapid adaptive camouflage in cuttlefish.

PubMed

Chiao, Chuan-Chin; Chubb, Charles; Hanlon, Roger T

2015-09-01

We review recent research on the visual mechanisms of rapid adaptive camouflage in cuttlefish. These neurophysiologically complex marine invertebrates can camouflage themselves against almost any background, yet their ability to quickly (0.5-2 s) alter their body patterns on different visual backgrounds poses a vexing challenge: how to pick the correct body pattern amongst their repertoire. The ability of cuttlefish to change appropriately requires a visual system that can rapidly assess complex visual scenes and produce the motor responses-the neurally controlled body patterns-that achieve camouflage. Using specifically designed visual backgrounds and assessing the corresponding body patterns quantitatively, we and others have uncovered several aspects of scene variation that are important in regulating cuttlefish patterning responses. These include spatial scale of background pattern, background intensity, background contrast, object edge properties, object contrast polarity, object depth, and the presence of 3D objects. Moreover, arm postures and skin papillae are also regulated visually for additional aspects of concealment. By integrating these visual cues, cuttlefish are able to rapidly select appropriate body patterns for concealment throughout diverse natural environments. This sensorimotor approach of studying cuttlefish camouflage thus provides unique insights into the mechanisms of visual perception in an invertebrate image-forming eye.

Fringe order correction for the absolute phase recovered by two selected spatial frequency fringe projections in fringe projection profilometry.

PubMed

Ding, Yi; Peng, Kai; Yu, Miao; Lu, Lei; Zhao, Kun

2017-08-01

The performance of the two selected spatial frequency phase unwrapping methods is limited by a phase error bound beyond which errors will occur in the fringe order leading to a significant error in the recovered absolute phase map. In this paper, we propose a method to detect and correct the wrong fringe orders. Two constraints are introduced during the fringe order determination of two selected spatial frequency phase unwrapping methods. A strategy to detect and correct the wrong fringe orders is also described. Compared with the existing methods, we do not need to estimate the threshold associated with absolute phase values to determine the fringe order error, thus making it more reliable and avoiding the procedure of search in detecting and correcting successive fringe order errors. The effectiveness of the proposed method is validated by the experimental results.

A new surgical technique for concealed penis using an advanced musculocutaneous scrotal flap.

PubMed

Han, Dong-Seok; Jang, Hoon; Youn, Chang-Shik; Yuk, Seung-Mo

2015-06-19

Until recently, no single, universally accepted surgical method has existed for all types of concealed penis repairs. We describe a new surgical technique for repairing concealed penis by using an advanced musculocutaneous scrotal flap. From January 2010 to June 2014, we evaluated 12 patients (12-40 years old) with concealed penises who were surgically treated with an advanced musculocutaneous scrotal flap technique after degloving through a ventral approach. All the patients were scheduled for regular follow-up at 6, 12, and 24 weeks postoperatively. The satisfaction grade for penile size, morphology, and voiding status were evaluated using a questionnaire preoperatively and at all of the follow-ups. Information regarding complications was obtained during the postoperative hospital stay and at all follow-ups. The patients' satisfaction grades, which included the penile size, morphology, and voiding status, improved postoperatively compared to those preoperatively. All patients had penile lymphedema postoperatively; however, this disappeared within 6 weeks. There were no complications such as skin necrosis and contracture, voiding difficulty, or erectile dysfunction. Our advanced musculocutaneous scrotal flap technique for concealed penis repair is technically easy and safe. In addition, it provides a good cosmetic appearance, functional outcomes and excellent postoperative satisfaction grades. Lastly, it seems applicable in any type of concealed penis, including cases in which the ventral skin defect is difficult to cover.

Research on image evidence in land supervision and GIS management

NASA Astrophysics Data System (ADS)

Li, Qiu; Wu, Lixin

2006-10-01

Land resource development and utilization brings many problems. The numbers, the scale and volume of illegal land use cases are on the increasing. Since the territory is vast, and the land violations are concealment, it is difficulty for an effective land supervision and management. In this paper, the concepts of evidence, and preservation of evidence were described first. The concepts of image evidence (IE), natural evidence (NE), natural preservation of evidence (NPE), general preservation of evidence (GPE) were proposed based on the characteristics of remote sensing image (RSI) which has a characteristic of objectiveness, truthfulness, high spatial resolution, more information included. Using MapObjects and Visual Basic 6.0, under the Access management to implement the conjunction of spatial vector database and attribute data table; taking RSI as the data sources and background layer; combining the powerful management of geographic information system (GIS) for spatial data, and visual analysis, a land supervision and GIS management system was design and implemented based on NPE. The practical use in Beijing shows that the system is running well, and solved some problems in land supervision and management.

Distance-dependent pattern blending can camouflage salient aposematic signals.

PubMed

Barnett, James B; Cuthill, Innes C; Scott-Samuel, Nicholas E

2017-07-12

The effect of viewing distance on the perception of visual texture is well known: spatial frequencies higher than the resolution limit of an observer's visual system will be summed and perceived as a single combined colour. In animal defensive colour patterns, distance-dependent pattern blending may allow aposematic patterns, salient at close range, to match the background to distant observers. Indeed, recent research has indicated that reducing the distance from which a salient signal can be detected can increase survival over camouflage or conspicuous aposematism alone. We investigated whether the spatial frequency of conspicuous and cryptically coloured stripes affects the rate of avian predation. Our results are consistent with pattern blending acting to camouflage salient aposematic signals effectively at a distance. Experiments into the relative rate of avian predation on edible model caterpillars found that increasing spatial frequency (thinner stripes) increased survival. Similarly, visual modelling of avian predators showed that pattern blending increased the similarity between caterpillar and background. These results show how a colour pattern can be tuned to reveal or conceal different information at different distances, and produce tangible survival benefits. © 2017 The Author(s).

Cancer survivors' concealment or disclosure of diagnosis: Implications for return to work.

PubMed

Morrison, T L; Thomas, R L

2015-01-01

The ability to return to work (RTW) is a significant quality of life indicator for many working aged cancer survivors. In the void of available support, many are left to independently navigate the RTW process which includes such important considerations as disclosure or concealment of diagnosis with concomitant sequellae. This article reviews participants' variable approaches to concealment, disclosure, or even an open educative stance as well as the associated benefits and limitations. Photovoice methods combined with interviewing. While most participants disclosed their diagnosis and many extolled the benefits of an open, educative stance, there were drawbacks experienced. Similarly, those who concealed their diagnosis also experienced benefits and challenges. In the current void of appropriate cancer rehabilitation supports, cancer survivors must independently negotiate their RTW process. Although most participants openly disclosed their diagnosis and associated limitations, a few concealed or camouflaged. There are benefits and limitations to both approaches of which survivors should be made aware at the outset as such will shape their RTW experience. Multidisciplinary rehabilitation support services would best guide survivors' management of the myriad of factors that will impact their work reintegration.

Decision Makers Use Norms, Not Cost-Benefit Analysis, When Choosing to Conceal or Reveal Unfair Rewards

PubMed Central

Heimann, Marco; Girotto, Vittorio; Legrenzi, Paolo; Bonnefon, Jean-François

2013-01-01

We introduce the Conceal or Reveal Dilemma, in which individuals receive unfair benefits, and must decide whether to conceal or to reveal this unfair advantage. This dilemma has two important characteristics: it does not lend itself easily to cost-benefit analysis, neither to the application of any strong universal norm. As a consequence, it is ideally suited to the study of interindividual and intercultural variations in moral-economic norms. In this paper we focus on interindividual variations, and we report four studies showing that individuals cannot be swayed by financial incentives to conceal or to reveal, and follow instead fixed, idiosyncratic strategies. We discuss how this result can be extended to individual and cultural variations in the tendency to display or to hide unfair rewards. PMID:24066040

Decision makers use norms, not cost-benefit analysis, when choosing to conceal or reveal unfair rewards.

PubMed

Heimann, Marco; Girotto, Vittorio; Legrenzi, Paolo; Bonnefon, Jean-François

2013-01-01

We introduce the Conceal or Reveal Dilemma, in which individuals receive unfair benefits, and must decide whether to conceal or to reveal this unfair advantage. This dilemma has two important characteristics: it does not lend itself easily to cost-benefit analysis, neither to the application of any strong universal norm. As a consequence, it is ideally suited to the study of interindividual and intercultural variations in moral-economic norms. In this paper we focus on interindividual variations, and we report four studies showing that individuals cannot be swayed by financial incentives to conceal or to reveal, and follow instead fixed, idiosyncratic strategies. We discuss how this result can be extended to individual and cultural variations in the tendency to display or to hide unfair rewards.

Optimal configurations of spatial scale for grid cell firing under noise and uncertainty

PubMed Central

Towse, Benjamin W.; Barry, Caswell; Bush, Daniel; Burgess, Neil

2014-01-01

We examined the accuracy with which the location of an agent moving within an environment could be decoded from the simulated firing of systems of grid cells. Grid cells were modelled with Poisson spiking dynamics and organized into multiple ‘modules’ of cells, with firing patterns of similar spatial scale within modules and a wide range of spatial scales across modules. The number of grid cells per module, the spatial scaling factor between modules and the size of the environment were varied. Errors in decoded location can take two forms: small errors of precision and larger errors resulting from ambiguity in decoding periodic firing patterns. With enough cells per module (e.g. eight modules of 100 cells each) grid systems are highly robust to ambiguity errors, even over ranges much larger than the largest grid scale (e.g. over a 500 m range when the maximum grid scale is 264 cm). Results did not depend strongly on the precise organization of scales across modules (geometric, co-prime or random). However, independent spatial noise across modules, which would occur if modules receive independent spatial inputs and might increase with spatial uncertainty, dramatically degrades the performance of the grid system. This effect of spatial uncertainty can be mitigated by uniform expansion of grid scales. Thus, in the realistic regimes simulated here, the optimal overall scale for a grid system represents a trade-off between minimizing spatial uncertainty (requiring large scales) and maximizing precision (requiring small scales). Within this view, the temporary expansion of grid scales observed in novel environments may be an optimal response to increased spatial uncertainty induced by the unfamiliarity of the available spatial cues. PMID:24366144

Small threat and contraband detection with TNA-based systems.

PubMed

Shaw, T J; Brown, D; D'Arcy, J; Liu, F; Shea, P; Sivakumar, M; Gozani, T

2005-01-01

The detection of small threats, such as explosives, drugs, and chemical weapons, concealed or encased in surrounding material, is a major concern in areas from security checkpoints to UneXploded Ordnance (UXO) clearance. Techniques such as X-ray and trace detection are often ineffectual in these applications. Thermal neutron analysis (TNA) provides an effective method for detecting concealed threats. This paper shows the effectiveness of Ancore's SPEDS, based on TNA, in detecting concealed liquid threats and differentiating live from inert mortar shells.

Discrete distributed strain sensing of intelligent structures

NASA Technical Reports Server (NTRS)

Anderson, Mark S.; Crawley, Edward F.

1992-01-01

Techniques are developed for the design of discrete highly distributed sensor systems for use in intelligent structures. First the functional requirements for such a system are presented. Discrete spatially averaging strain sensors are then identified as satisfying the functional requirements. A variety of spatial weightings for spatially averaging sensors are examined, and their wave number characteristics are determined. Preferable spatial weightings are identified. Several numerical integration rules used to integrate such sensors in order to determine the global deflection of the structure are discussed. A numerical simulation is conducted using point and rectangular sensors mounted on a cantilevered beam under static loading. Gage factor and sensor position uncertainties are incorporated to assess the absolute error and standard deviation of the error in the estimated tip displacement found by numerically integrating the sensor outputs. An experiment is carried out using a statically loaded cantilevered beam with five point sensors. It is found that in most cases the actual experimental error is within one standard deviation of the absolute error as found in the numerical simulation.

Comparison of different spatial transformations applied to EEG data: A case study of error processing.

PubMed

Cohen, Michael X

2015-09-01

The purpose of this paper is to compare the effects of different spatial transformations applied to the same scalp-recorded EEG data. The spatial transformations applied are two referencing schemes (average and linked earlobes), the surface Laplacian, and beamforming (a distributed source localization procedure). EEG data were collected during a speeded reaction time task that provided a comparison of activity between error vs. correct responses. Analyses focused on time-frequency power, frequency band-specific inter-electrode connectivity, and within-subject cross-trial correlations between EEG activity and reaction time. Time-frequency power analyses showed similar patterns of midfrontal delta-theta power for errors compared to correct responses across all spatial transformations. Beamforming additionally revealed error-related anterior and lateral prefrontal beta-band activity. Within-subject brain-behavior correlations showed similar patterns of results across the spatial transformations, with the correlations being the weakest after beamforming. The most striking difference among the spatial transformations was seen in connectivity analyses: linked earlobe reference produced weak inter-site connectivity that was attributable to volume conduction (zero phase lag), while the average reference and Laplacian produced more interpretable connectivity results. Beamforming did not reveal any significant condition modulations of connectivity. Overall, these analyses show that some findings are robust to spatial transformations, while other findings, particularly those involving cross-trial analyses or connectivity, are more sensitive and may depend on the use of appropriate spatial transformations. Copyright © 2014 Elsevier B.V. All rights reserved.

Spatial uncertainty analysis: Propagation of interpolation errors in spatially distributed models

USGS Publications Warehouse

Phillips, D.L.; Marks, D.G.

1996-01-01

In simulation modelling, it is desirable to quantify model uncertainties and provide not only point estimates for output variables but confidence intervals as well. Spatially distributed physical and ecological process models are becoming widely used, with runs being made over a grid of points that represent the landscape. This requires input values at each grid point, which often have to be interpolated from irregularly scattered measurement sites, e.g., weather stations. Interpolation introduces spatially varying errors which propagate through the model We extended established uncertainty analysis methods to a spatial domain for quantifying spatial patterns of input variable interpolation errors and how they propagate through a model to affect the uncertainty of the model output. We applied this to a model of potential evapotranspiration (PET) as a demonstration. We modelled PET for three time periods in 1990 as a function of temperature, humidity, and wind on a 10-km grid across the U.S. portion of the Columbia River Basin. Temperature, humidity, and wind speed were interpolated using kriging from 700- 1000 supporting data points. Kriging standard deviations (SD) were used to quantify the spatially varying interpolation uncertainties. For each of 5693 grid points, 100 Monte Carlo simulations were done, using the kriged values of temperature, humidity, and wind, plus random error terms determined by the kriging SDs and the correlations of interpolation errors among the three variables. For the spring season example, kriging SDs averaged 2.6??C for temperature, 8.7% for relative humidity, and 0.38 m s-1 for wind. The resultant PET estimates had coefficients of variation (CVs) ranging from 14% to 27% for the 10-km grid cells. Maps of PET means and CVs showed the spatial patterns of PET with a measure of its uncertainty due to interpolation of the input variables. This methodology should be applicable to a variety of spatially distributed models using interpolated inputs.

Three-dimensional FLASH Laser Radar Range Estimation via Blind Deconvolution

DTIC Science & Technology

2009-10-01

scene can result in errors due to several factors including the optical spatial impulse response, detector blurring, photon noise , timing jitter, and...estimation error include spatial blur, detector blurring, noise , timing jitter, and inter-sample targets. Unlike previous research, this paper ac- counts...for pixel coupling by defining the range image mathematical model as a 2D convolution between the system spatial impulse response and the object (target

Knowledge of display rules in prelingually deaf and hearing children.

PubMed

Hosie, J A; Russell, P A; Gray, C D; Scott, C; Hunter, N; Banks, J S; Macaulay, M C

2000-03-01

Deaf children of elementary and secondary school age participated in a study designed to examine their understanding of display rules, the principles governing the expression and concealment of emotion in social situations. The results showed that deaf children's knowledge of display rules, as measured by their reported concealment of emotion, was comparable to that of hearing children of the same age. However, deaf children were less likely to report that they would conceal happiness and anger. They were also less likely to produce reasons for concealing emotion and a smaller proportion of their reasons were prosocial, that is, relating to the feelings of others. The results suggest that the understanding of display rules (which function to protect the feelings of other people) may develop more gradually in deaf children raised in a spoken language environment than it does in hearing children.

Determinants of felt stigma in epilepsy.

PubMed

Aydemir, N; Kaya, B; Yıldız, G; Öztura, I; Baklan, B

2016-05-01

The present study aimed to determine the level of felt stigma, overprotection, concealment, and concerns related to epilepsy in different life domains by using culturally-specific scales for Turkish individuals with epilepsy. Also, it aimed to detect relations among the study variables and to determine the variables which predict felt stigma. For this purpose, felt stigma scale, overprotection scale, concealment of epilepsy scale, and concerns of epilepsy scale were administered to two hundred adult persons with epilepsy (PWE). The results showed that almost half of the participants reported felt stigma, overprotection, concealment of epilepsy, concerns related to future occupation, and concerns related to social life. Almost all the study variables show correlations with each other. Concealment of epilepsy, concerns related to social life, and concerns related to future occupation were found as the predictors of felt stigma. Copyright © 2016 Elsevier Inc. All rights reserved.

Parasitism rate, parasitoid community composition and host specificity on exposed and semi-concealed caterpillars from a tropical rainforest.

PubMed

Hrcek, Jan; Miller, Scott E; Whitfield, James B; Shima, Hiroshi; Novotny, Vojtech

2013-10-01

The processes maintaining the enormous diversity of herbivore-parasitoid food webs depend on parasitism rate and parasitoid host specificity. The two parameters have to be evaluated in concert to make conclusions about the importance of parasitoids as natural enemies and guide biological control. We document parasitism rate and host specificity in a highly diverse caterpillar-parasitoid food web encompassing 266 species of lepidopteran hosts and 172 species of hymenopteran or dipteran parasitoids from a lowland tropical forest in Papua New Guinea. We found that semi-concealed hosts (leaf rollers and leaf tiers) represented 84% of all caterpillars, suffered a higher parasitism rate than exposed caterpillars (12 vs. 5%) and their parasitoids were also more host specific. Semi-concealed hosts may therefore be generally more amenable to biological control by parasitoids than exposed ones. Parasitoid host specificity was highest in Braconidae, lower in Diptera: Tachinidae, and, unexpectedly, the lowest in Ichneumonidae. This result challenges the long-standing view of low host specificity in caterpillar-attacking Tachinidae and suggests higher suitability of Braconidae and lower suitability of Ichneumonidae for biological control of caterpillars. Semi-concealed hosts and their parasitoids are the largest, yet understudied component of caterpillar-parasitoid food webs. However, they still remain much closer in parasitism patterns to exposed hosts than to what literature reports on fully concealed leaf miners. Specifically, semi-concealed hosts keep an equally low share of idiobionts (2%) as exposed caterpillars.

Quantifying the impact of material-model error on macroscale quantities-of-interest using multiscale a posteriori error-estimation techniques

DOE PAGES

Brown, Judith A.; Bishop, Joseph E.

2016-07-20

An a posteriori error-estimation framework is introduced to quantify and reduce modeling errors resulting from approximating complex mesoscale material behavior with a simpler macroscale model. Such errors may be prevalent when modeling welds and additively manufactured structures, where spatial variations and material textures may be present in the microstructure. We consider a case where a <100> fiber texture develops in the longitudinal scanning direction of a weld. Transversely isotropic elastic properties are obtained through homogenization of a microstructural model with this texture and are considered the reference weld properties within the error-estimation framework. Conversely, isotropic elastic properties are considered approximatemore » weld properties since they contain no representation of texture. Errors introduced by using isotropic material properties to represent a weld are assessed through a quantified error bound in the elastic regime. Lastly, an adaptive error reduction scheme is used to determine the optimal spatial variation of the isotropic weld properties to reduce the error bound.« less

Seasonal Differences in Spatial Scales of Chlorophyll-A Concentration in Lake TAIHU，CHINA

NASA Astrophysics Data System (ADS)

Bao, Y.; Tian, Q.; Sun, S.; Wei, H.; Tian, J.

2012-08-01

Spatial distribution of chlorophyll-a (chla) concentration in Lake Taihu is non-uniform and seasonal variability. Chla concentration retrieval algorithms were separately established using measured data and remote sensing images (HJ-1 CCD and MODIS data) in October 2010, March 2011, and September 2011. Then parameters of semi- variance were calculated on the scale of 30m, 250m and 500m for analyzing spatial heterogeneity in different seasons. Finally, based on the definitions of Lumped chla (chlaL) and Distributed chla (chlaD), seasonal model of chla concentration scale error was built. The results indicated that: spatial distribution of chla concentration in spring was more uniform. In summer and autumn, chla concentration in the north of the lake such as Meiliang Bay and Zhushan Bay was higher than that in the south of Lake Taihu. Chla concentration on different scales showed the similar structure in the same season, while it had different structure in different seasons. And inversion chla concentration from MODIS 500m had a greater scale error. The spatial scale error changed with seasons. It was higher in summer and autumn than that in spring. The maximum relative error can achieve 23%.

Concealing with structured light.

PubMed

Sun, Jingbo; Zeng, Jinwei; Wang, Xi; Cartwright, Alexander N; Litchinitser, Natalia M

2014-02-13

While making objects less visible (or invisible) to a human eye or a radar has captured people's imagination for centuries, current attempts towards realization of this long-awaited functionality range from various stealth technologies to recently proposed cloaking devices. A majority of proposed approaches share a number of common deficiencies such as design complexity, polarization effects, bandwidth, losses and the physical size or shape requirement complicating their implementation especially at optical frequencies. Here we demonstrate an alternative way to conceal macroscopic objects by structuring light itself. In our approach, the incident light is transformed into an optical vortex with a dark core that can be used to conceal macroscopic objects. Once such a beam passed around the object it is transformed back into its initial Gaussian shape with minimum amplitude and phase distortions. Therefore, we propose to use that dark core of the vortex beam to conceal an object that is macroscopic yet small enough to fit the dark (negligibly low intensity) region of the beam. The proposed concealing approach is polarization independent, easy to fabricate, lossless, operates at wavelengths ranging from 560 to 700 nm, and can be used to hide macroscopic objects providing they are smaller than vortex core.

Cycles of abuse nurtured by concealment: a clinical report.

PubMed

Wijma, Barbro; Thapar-Björkert, Suruchi; Hammarström, Nevija Cah; Swahnberg, Katarina

2007-09-01

At present, health care staff do not seem to have sufficient knowledge about their patients' abusive experiences. The aim of the present study is to analyze and discuss what the implications might be for the encounter between patients and health care professionals, when experiences of abuse are concealed. The methodology of this article is varied: a personal narrative, medical records, sociological theoretical literature and empirical evidence. From the narrative we learn that concealment of abuse was devastating for the patient. She was "treated" in vain as a correct diagnosis was not made, while abuse by her father continued. Health care staff also violated her, which she told her therapist, but her protests were not acknowledged. Ten years of treatment thus made her even more sick. This case story focuses on the mechanisms which nurture concealment of a patient's history of abuse, such as structural and symbolic violence. We also suggest ways to break "cycles of abuse". Help the patient to stop concealing also means that she/he leaves a victim role, gets in charge of the situation and takes a first step towards empowerment. In this way, health care settings can become enabling and empowering environments.

[Cardioversion for paroxysmal supraventricular tachycardia during lung surgery in a patient with concealed Wolff-Parkinson-White syndrome].

PubMed

Sato, Yoshiharu; Nagata, Hirofumi; Inoda, Ayako; Miura, Hiroko; Watanabe, Yoko; Suzuki, Kenji

2014-10-01

We report a case of paroxysmal supraventricular tachycardia (PSVT) that occurred during video-assisted thoracoscopic (VATS) lobectomy in a patient with concealed Wolff-Parkinson-White (WPW) syndrome. A 59-year-old man with lung cancer was scheduled for VATS lobectomy under general anesthesia. After inserting a thoracic epidural catheter, general anesthesia was induced with intravenous administration of propofol. Anesthesia was maintained with inhalation of desfurane in an air/oxygen mixture and intravenous infusion of remifentanil. Recurrent PSVT occurred three times, and the last episode of PSVT continued for 50 minutes regardless of administration of antiarrhythmic drugs. Synchronized electric shock via adhesive electrode pads on the patient's chest successfully converted PSVT back to normal sinus rhythm. The remaining course and postoperative period were uneventful. An electrophysiological study performed after hospital discharge detected concealed WPW syndrome, which had contributed to the development of atrioventricular reciprocating tachycardia. Concealed WPW syndrome is a rare, but critical complication that could possibly cause lethal atrial tachyarrhythmias during the perioperative period. In the present case, cardioversion using adhesive electrode pads briefly terminated PSVT in a patient with concealed WPW syndrome.

Spatial Resolution, Grayscale, and Error Diffusion Trade-offs: Impact on Display System Design

NASA Technical Reports Server (NTRS)

Gille, Jennifer L. (Principal Investigator)

1996-01-01

We examine technology trade-offs related to grayscale resolution, spatial resolution, and error diffusion for tessellated display systems. We present new empirical results from our psychophysical study of these trade-offs and compare them to the predictions of a model of human vision.

Simulation of wave propagation in three-dimensional random media

NASA Astrophysics Data System (ADS)

Coles, Wm. A.; Filice, J. P.; Frehlich, R. G.; Yadlowsky, M.

1995-04-01

Quantitative error analyses for the simulation of wave propagation in three-dimensional random media, when narrow angular scattering is assumed, are presented for plane-wave and spherical-wave geometry. This includes the errors that result from finite grid size, finite simulation dimensions, and the separation of the two-dimensional screens along the propagation direction. Simple error scalings are determined for power-law spectra of the random refractive indices of the media. The effects of a finite inner scale are also considered. The spatial spectra of the intensity errors are calculated and compared with the spatial spectra of

Predictive value of ADAMTS-13 on concealed chronic renal failure in COPD patients

PubMed Central

Zeng, Mian; Chen, Qingui; Liang, Wenjie; He, Wanmei; Zheng, Haichong; Huang, Chunrong

2017-01-01

Background Impaired renal function is often neglected in COPD patients. Considering that COPD patients usually have an ongoing prothrombotic state and systemic inflammation status, we investigated the association among them and explored the predictive value of a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS-13), on concealed chronic renal failure (CRF) in COPD patients. Methods COPD patients were recruited from the First Affiliated Hospital of Sun Yat-Sen University between January 2015 and December 2016. Control was selected from contemporaneous hospitalized patients without COPD and matched by age and gender at a ratio of 1:1. Estimated glomerular filtration rate (eGFR) was calculated by using the Chronic Kidney Disease Epidemiology Collaboration formula, and all subjects were categorized as having normal renal function (eGFR ≥60 mL min−1 1.73 m−2) and having concealed CRF (normal serum creatinine while eGFR <60 mL min−1 1.73 m−2). Independent correlates of concealed CRF were investigated by logistic regression analysis, and receiver operating characteristic (ROC) curves were used to determine the predictive value of ADAMTS-13. Results In total, 106 COPD and 106 non-COPD patients were finally recruited, and the incidences of concealed CRF were 19.81% and 7.55%, respectively. ADAMTS-13 (odds ratio [OR] =0.858, 95% CI =0.795–0.926), D-dimer (OR =1.095, 95% CI =1.027–1.169), and C-reactive protein (OR =1.252, 95% CI =1.058–1.480) were significantly associated with concealed CRF. Sensitivity and specificity at an ADAMTS-13 cutoff of 318.72 ng/mL were 100% and 81.2%, respectively. The area under the ROC curve was 0.959. Conclusion Prothrombotic state and systemic inflammation status might contribute to explaining the high incidence of concealed CRF in COPD, and plasma ADAMTS-13 levels may serve as a strong predictor. PMID:29255356

Concealed renal failure and adverse drug reactions in older patients with type 2 diabetes mellitus.

PubMed

Corsonello, Andrea; Pedone, Claudio; Corica, Francesco; Mazzei, Bruno; Di Iorio, Angelo; Carbonin, Pierugo; Incalzi, Raffaele Antonelli

2005-09-01

In elderly patients serum creatinine may be normal despite decreased glomerular filtration rate (GFR). The aim of this study was to evaluate the prevalence of this "concealed" renal failure, i.e., renal failure with normal serum creatinine levels, in elderly diabetic patients, and to verify whether it is a risk factor for adverse drug reactions (ADR) to hydrosoluble drugs. We used data on 2257 hospitalized patients with type 2 diabetes mellitus enrolled in the Gruppo Italiano di Farmacovigilanza nell'Anziano study. On the basis of serum creatinine and calculated GFR, patients were grouped as follows: normal renal function (normal serum creatinine levels and normal GFR), concealed (normal serum creatinine levels and reduced GFR), or overt (increased creatinine levels and reduced GFR) renal failure. GFR was calculated using the Modification of Diet in Renal Disease (MDRD) equation. The outcome of the study was the incidence of ADR to hydrosoluble drugs during the hospital stay. The relationship between renal function and ADR was evaluated using Cox regression analysis including potential confounders. Concealed renal failure was observed in 363 (16.1%) of patients studied. Patients with concealed or overt renal failure were older, had more frequently cognitive impairment and polypharmacy, and had lower serum albumin levels than did those with normal renal function. Both concealed (hazard ratio = 1.90; 95% confidence interval, 1.04-3.48; p =.036) and overt (hazard ratio = 2.23; 95% confidence interval, 1.40-3.55; p =.001) renal failure were significantly associated with ADR to hydrosoluble drugs. The use of more than four drugs also qualified as an independent risk factor for ADRs to hydrosoluble drugs during hospital stay. Older diabetic patients should be systematically screened to ascertain the presence of concealed renal failure in an attempt to optimize the pharmacological treatment and reduce the risk of ADRs.

How do patients with neglect see a horizontal line? Analysis of performances in coloured line bisection task.

PubMed

Misonou, Kaori; Ishiai, Sumio; Seki, Keiko; Koyama, Yasumasa; Nakano, Naomi

2004-06-01

Twelve patients with left unilateral spatial neglect were examined with a newly devised "coloured line bisection task". They were presented with a horizontal line printed in blue on one side and in red on the other side; the proportions of the blue and red segments were varied. Immediately after placement of the subjective midpoint, the line was concealed and the patients were asked to name the colours of the right and left ends. Five patients who identified the left-end colour almost correctly had no visual field defect, while the other seven whose colour naming was impaired on the left side had left visual field defect. The rightward bisection errors were similarly distributed in the fair and poor colour-naming patients except for two patients from the latter group. The lesions of the fair colour-naming patients spared the lingual and fusiform gyri, which are known to be engaged in colour processing. Patients with neglect whose visual field is preserved may neglect the leftward extension of a line but not the colour in the neglected space. The poor colour-naming patients frequently failed to name the left-end colour that appeared to the left of their subjective midpoint, which indicates that they hardly searched leftward beyond that point. In such trials, they reported that the left end had the same colour as the right end. The results suggest that in patients with neglect and left visual field defect, both the leftward extent and the colour of a line may be represented on the basis of the information from the attended right segment.

Psychological and social correlates of HIV status disclosure: the significance of stigma visibility.

PubMed

Stutterheim, Sarah E; Bos, Arjan E R; Pryor, John B; Brands, Ronald; Liebregts, Maartje; Schaalma, Herman P

2011-08-01

HIV-related stigma, psychological distress, self-esteem, and social support were investigated in a sample comprising people who have concealed their HIV status to all but a selected few (limited disclosers), people who could conceal but chose to be open (full disclosers), and people who had visible symptoms that made concealing difficult (visibly stigmatized). The visibly stigmatized and full disclosers reported significantly more stigma experiences than limited disclosers, but only the visibly stigmatized reported more psychological distress, lower self-esteem, and less social support than limited disclosers. This suggests that having a visible stigma is more detrimental than having a concealable stigma. Differences in psychological distress and self-esteem between the visibly stigmatized and full disclosers were mediated by social support while differences between the visibly stigmatized and limited disclosers were mediated by both social support and stigma. These findings suggest that social support buffers psychological distress in people with HIV.

Sexual and gender minority identity disclosure during undergraduate medical education: "in the closet" in medical school.

PubMed

Mansh, Matthew; White, William; Gee-Tong, Lea; Lunn, Mitchell R; Obedin-Maliver, Juno; Stewart, Leslie; Goldsmith, Elizabeth; Brenman, Stephanie; Tran, Eric; Wells, Maggie; Fetterman, David; Garcia, Gabriel

2015-05-01

To assess identity disclosure among sexual and gender minority (SGM) students pursuing undergraduate medical training in the United States and Canada. From 2009 to 2010, a survey was made available to all medical students enrolled in the 176 MD- and DO-granting medical schools in the United States and Canada. Respondents were asked about their sexual and gender identity, whether they were "out" (i.e., had publicly disclosed their identity), and, if they were not, their reasons for concealing their identity. The authors used a mixed-methods approach and analyzed quantitative and qualitative survey data. Of 5,812 completed responses (of 101,473 eligible respondents; response rate 5.7%), 920 (15.8%) students from 152 (of 176; 86.4%) institutions identified as SGMs. Of the 912 sexual minorities, 269 (29.5%) concealed their sexual identity in medical school. Factors associated with sexual identity concealment included sexual minority identity other than lesbian or gay, male gender, East Asian race, and medical school enrollment in the South or Central regions of North America. The most common reasons for concealing one's sexual identity were "nobody's business" (165/269; 61.3%), fear of discrimination in medical school (117/269; 43.5%), and social or cultural norms (110/269; 40.9%). Of the 35 gender minorities, 21 (60.0%) concealed their gender identity, citing fear of discrimination in medical school (9/21; 42.9%) and lack of support (9/21; 42.9%). SGM students continue to conceal their identity during undergraduate medical training. Medical institutions should adopt targeted policies and programs to better support these individuals.

Microwave Technique for Detecting and Locating Concealed Weapons

DOT National Transportation Integrated Search

1971-12-01

The subject of this report is the evaluation of a microwave technique for detecting and locating weapons concealed under clothing. The principal features of this technique are: persons subjected to search are not exposed to 'objectional' microwave ra...

Perceptual Color Characterization of Cameras

PubMed Central

Vazquez-Corral, Javier; Connah, David; Bertalmío, Marcelo

2014-01-01

Color camera characterization, mapping outputs from the camera sensors to an independent color space, such as XY Z, is an important step in the camera processing pipeline. Until now, this procedure has been primarily solved by using a 3 × 3 matrix obtained via a least-squares optimization. In this paper, we propose to use the spherical sampling method, recently published by Finlayson et al., to perform a perceptual color characterization. In particular, we search for the 3 × 3 matrix that minimizes three different perceptual errors, one pixel based and two spatially based. For the pixel-based case, we minimize the CIE ΔE error, while for the spatial-based case, we minimize both the S-CIELAB error and the CID error measure. Our results demonstrate an improvement of approximately 3% for the ΔE error, 7% for the S-CIELAB error and 13% for the CID error measures. PMID:25490586

Examining Impulse-Variability in Kicking.

PubMed

Chappell, Andrew; Molina, Sergio L; McKibben, Jonathon; Stodden, David F

2016-07-01

This study examined variability in kicking speed and spatial accuracy to test the impulse-variability theory prediction of an inverted-U function and the speed-accuracy trade-off. Twenty-eight 18- to 25-year-old adults kicked a playground ball at various percentages (50-100%) of their maximum speed at a wall target. Speed variability and spatial error were analyzed using repeated-measures ANOVA with built-in polynomial contrasts. Results indicated a significant inverse linear trajectory for speed variability (p < .001, η2= .345) where 50% and 60% maximum speed had significantly higher variability than the 100% condition. A significant quadratic fit was found for spatial error scores of mean radial error (p < .0001, η2 = .474) and subject-centroid radial error (p < .0001, η2 = .453). Findings suggest variability and accuracy of multijoint, ballistic skill performance may not follow the general principles of impulse-variability theory or the speed-accuracy trade-off.

Left neglect dyslexia: Perseveration and reading error types.

PubMed

Ronchi, Roberta; Algeri, Lorella; Chiapella, Laura; Gallucci, Marcello; Spada, Maria Simonetta; Vallar, Giuseppe

2016-08-01

Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect. Copyright © 2016 Elsevier Ltd. All rights reserved.

Divided spatial attention and feature-mixing errors.

PubMed

Golomb, Julie D

2015-11-01

Spatial attention is thought to play a critical role in feature binding. However, often multiple objects or locations are of interest in our environment, and we need to shift or split attention between them. Recent evidence has demonstrated that shifting and splitting spatial attention results in different types of feature-binding errors. In particular, when two locations are simultaneously sharing attentional resources, subjects are susceptible to feature-mixing errors; that is, they tend to report a color that is a subtle blend of the target color and the color at the other attended location. The present study was designed to test whether these feature-mixing errors are influenced by target-distractor similarity. Subjects were cued to split attention across two different spatial locations, and were subsequently presented with an array of colored stimuli, followed by a postcue indicating which color to report. Target-distractor similarity was manipulated by varying the distance in color space between the two attended stimuli. Probabilistic modeling in all cases revealed shifts in the response distribution consistent with feature-mixing errors; however, the patterns differed considerably across target-distractor color distances. With large differences in color, the findings replicated the mixing result, but with small color differences, repulsion was instead observed, with the reported target color shifted away from the other attended color.

Spatiotemporal integration for tactile localization during arm movements: a probabilistic approach.

PubMed

Maij, Femke; Wing, Alan M; Medendorp, W Pieter

2013-12-01

It has been shown that people make systematic errors in the localization of a brief tactile stimulus that is delivered to the index finger while they are making an arm movement. Here we modeled these spatial errors with a probabilistic approach, assuming that they follow from temporal uncertainty about the occurrence of the stimulus. In the model, this temporal uncertainty converts into a spatial likelihood about the external stimulus location, depending on arm velocity. We tested the prediction of the model that the localization errors depend on arm velocity. Participants (n = 8) were instructed to localize a tactile stimulus that was presented to their index finger while they were making either slow- or fast-targeted arm movements. Our results confirm the model's prediction that participants make larger localization errors when making faster arm movements. The model, which was used to fit the errors for both slow and fast arm movements simultaneously, accounted very well for all the characteristics of these data with temporal uncertainty in stimulus processing as the only free parameter. We conclude that spatial errors in dynamic tactile perception stem from the temporal precision with which tactile inputs are processed.

The use of far infra-red radiation for the detection of concealed metal objects

DOT National Transportation Integrated Search

1971-11-01

The use of infrared radiation for the detection of concealed metal objects has been investigated both theoretically and experimentally. The investigation was divided into two phases, one which considered passive techniques, and another which involved...

The use of far infra-red radiation for the detection of concealed metal objects.

DOT National Transportation Integrated Search

1971-11-01

Abstract The use of infrared radiation for the detection : of concealed metal objects has been investigated both : theoretically and experimentally. The investigation was : divided into two phases, one which considered passive : techniques, and anoth...

20 CFR 404.502 - Overpayments.

Code of Federal Regulations, 2010 CFR

2010-04-01

... representative payee for payments made after the beneficiary's death. We will not recover such overpayments from... intentional false statement or representation, or willful concealment of, or deliberate failure to furnish... individual's intentional false statement or representation, or willful concealment of, or deliberate failure...

Management of concealed penis with modified penoplasty.

PubMed

Xu, Jian-Guo; Lv, Chuan; Wang, Yu-Chong; Zhu, Ji; Xue, Chun-Yu

2015-03-01

To investigate the effect of penile degloving in combination with penoscrotal angle reconstruction for the correction of concealed penis. A foreskin circumcision incision was made along the coronal sulcus. After a sharp dissection under the superficial layer of tunica albuginea, the penile shaft was degloved to release the fibrous bands of the tunica dartos. Through a longitudinal incision or Z-plasty at the penoscrotal junction, securing of the tunica albuginea to the proximal tunica dartos was performed. The penoscrotal angle was reconstructed. This procedure effectively corrected the concealed penis, while correcting other problems such as phimosis. From August 2008 to August 2013, we performed 41 procedures for concealed penis. Correction was successful in all patients with an improved median length of 2.1 cm in the flaccid state. Follow-up ranged from 6 months to 2 years, and satisfactory cosmetic outcomes were obtained without scars or erectile discomfort. Our technique includes degloving and penoscrotal angle reconstruction, which provides proper visualization for fixation of the penile base. The longitudinal or Z-plasty incision also opened the degloving dead cavity, which was good for drainage. The procedure is straight forward with good functional and cosmetic outcomes and is thus ideal for correction of the concealed penis. Copyright © 2015 Elsevier Inc. All rights reserved.

Modified penoplasty for concealed penis in children.

PubMed

Yang, Tianyou; Zhang, Liyu; Su, Cheng; Li, Zhongmin; Wen, Yingquan

2013-09-01

To report a modified penoplasty technique for concealed penis in children. Between January 2006 and June 2012, 201 cases of concealed penis were surgically repaired with modified penoplasty. The modified penoplasty technique consisted of 3 major steps: (1) degloved the penile skin and excised the inner prepuce, (2) advanced penoscrotal skin to cover penile shaft, and (3) fixed the penis base and reconstructed the penoscrotal angle. Two hundred one cases of concealed penis were enrolled in this study over a period of 6 years. Mean age at the time of surgery was 5.3 years (range 1-13 years) and mean operative time was 40 minutes (range 30-65minutes). All patients were routinely followed up at 1, 3, and 6 months after surgery. Most patients developed postoperative edema and were resolved within 1 month, whereas 20 cases developed prolonged postoperative edema, especially at the site of frenulum, which took 3 months to be resolved. Ten cases had retraction after surgery. No erection difficulties were recorded. Patients/parents reported better hygiene and improved visualization and accessibility of penis after surgery and were satisfied with the cosmetic outcome. The result of this study shows that the modified penoplasty technique is a simple, safe, and effective procedure for concealed penis with satisfied cosmetic outcome. Copyright © 2013 Elsevier Inc. All rights reserved.

Hiding and finding: the relationship between visual concealment and visual search.

PubMed

Smilek, Daniel; Weinheimer, Laura; Kwan, Donna; Reynolds, Mike; Kingstone, Alan

2009-11-01

As an initial step toward developing a theory of visual concealment, we assessed whether people would use factors known to influence visual search difficulty when the degree of concealment of objects among distractors was varied. In Experiment 1, participants arranged search objects (shapes, emotional faces, and graphemes) to create displays in which the targets were in plain sight but were either easy or hard to find. Analyses of easy and hard displays created during Experiment 1 revealed that the participants reliably used factors known to influence search difficulty (e.g., eccentricity, target-distractor similarity, presence/absence of a feature) to vary the difficulty of search across displays. In Experiment 2, a new participant group searched for the targets in the displays created by the participants in Experiment 1. Results indicated that search was more difficult in the hard than in the easy condition. In Experiments 3 and 4, participants used presence versus absence of a feature to vary search difficulty with several novel stimulus sets. Taken together, the results reveal a close link between the factors that govern concealment and the factors known to influence search difficulty, suggesting that a visual search theory can be extended to form the basis of a theory of visual concealment.

Prospective effects of social support on internalized homonegativity and sexual identity concealment among middle-aged and older gay men: a longitudinal cohort study.

PubMed

Lyons, Anthony; Pepping, Christopher A

2017-09-01

Middle-aged and older gay men experience higher rates of depression and anxiety compared to their heterosexual counterparts, with internalized homonegativity and sexual identity concealment known to be major stress-related contributors. This study examined the prospective effect of different types and sources of social support on internalized homonegativity and sexual identity concealment experienced among middle-aged and older gay men. A longitudinal survey involving two waves of data collection separated by 12 months was conducted among a cohort of 186 gay-identified men aged 40 years and older. Two types of social support were found to be important. Greater baseline tangible or practical support independently predicted lower internalized homonegativity at 12-month follow-up, while greater baseline emotional or psychological support independently predicted a lower tendency toward sexual identity concealment at 12-month follow-up. Greater baseline support from community or government agencies, such as health services and support organizations, predicted higher internalized homonegativity at 12-month follow-up. These findings suggest that tangible and emotional support may be beneficial in reducing internalized homonegativity and sexual identity concealment among middle-aged and older gay men. Ensuring that services provide environments that do not compound the stressful impact of stigma also appears to be important.

Benefit transfer and spatial heterogeneity of preferences for water quality improvements.

PubMed

Martin-Ortega, J; Brouwer, R; Ojea, E; Berbel, J

2012-09-15

The improvement in the water quality resulting from the implementation of the EU Water Framework Directive is expected to generate substantial non-market benefits. A wide spread estimation of these benefits across Europe will require the application of benefit transfer. We use a spatially explicit valuation design to account for the spatial heterogeneity of preferences to help generate lower transfer errors. A map-based choice experiment is applied in the Guadalquivir River Basin (Spain), accounting simultaneously for the spatial distribution of water quality improvements and beneficiaries. Our results show that accounting for the spatial heterogeneity of preferences generally produces lower transfer errors. Copyright © 2012 Elsevier Ltd. All rights reserved.

Testing a dynamic-field account of interactions between spatial attention and spatial working memory.

PubMed

Johnson, Jeffrey S; Spencer, John P

2016-05-01

Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: If attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal was reexamined in light of a neural-process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color discrimination task during the delay interval of a spatial-recall task. In the critical shifting-attention condition, the color stimulus could appear either toward or away from the midline reference axis, relative to the memorized location. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors, but no change in directional errors, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations-as predicted by the model-systematic changes in the patterns of spatial-recall errors should occur that would depend on the direction of the shift. The results were consistent with the latter possibility-recall errors were biased toward the locations of discrimination targets appearing during the delay.

Testing a Dynamic Field Account of Interactions between Spatial Attention and Spatial Working Memory

PubMed Central

Johnson, Jeffrey S.; Spencer, John P.

2016-01-01

Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: if attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal is reexamined in light of a neural process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color-discrimination task during the delay interval of a spatial recall task. In the critical shifting attention condition, the color stimulus could appear either toward or away from the memorized location relative to a midline reference axis. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors but no change in directional error, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations—as predicted by the model—there should be systematic changes in the pattern of spatial recall errors depending on the direction of the shift. Results were consistent with the latter possibility—recall errors were biased toward the location of discrimination targets appearing during the delay. PMID:26810574

A heteroskedastic error covariance matrix estimator using a first-order conditional autoregressive Markov simulation for deriving asympotical efficient estimates from ecological sampled Anopheles arabiensis aquatic habitat covariates

PubMed Central

Jacob, Benjamin G; Griffith, Daniel A; Muturi, Ephantus J; Caamano, Erick X; Githure, John I; Novak, Robert J

2009-01-01

Background Autoregressive regression coefficients for Anopheles arabiensis aquatic habitat models are usually assessed using global error techniques and are reported as error covariance matrices. A global statistic, however, will summarize error estimates from multiple habitat locations. This makes it difficult to identify where there are clusters of An. arabiensis aquatic habitats of acceptable prediction. It is therefore useful to conduct some form of spatial error analysis to detect clusters of An. arabiensis aquatic habitats based on uncertainty residuals from individual sampled habitats. In this research, a method of error estimation for spatial simulation models was demonstrated using autocorrelation indices and eigenfunction spatial filters to distinguish among the effects of parameter uncertainty on a stochastic simulation of ecological sampled Anopheles aquatic habitat covariates. A test for diagnostic checking error residuals in an An. arabiensis aquatic habitat model may enable intervention efforts targeting productive habitats clusters, based on larval/pupal productivity, by using the asymptotic distribution of parameter estimates from a residual autocovariance matrix. The models considered in this research extends a normal regression analysis previously considered in the literature. Methods Field and remote-sampled data were collected during July 2006 to December 2007 in Karima rice-village complex in Mwea, Kenya. SAS 9.1.4® was used to explore univariate statistics, correlations, distributions, and to generate global autocorrelation statistics from the ecological sampled datasets. A local autocorrelation index was also generated using spatial covariance parameters (i.e., Moran's Indices) in a SAS/GIS® database. The Moran's statistic was decomposed into orthogonal and uncorrelated synthetic map pattern components using a Poisson model with a gamma-distributed mean (i.e. negative binomial regression). The eigenfunction values from the spatial configuration matrices were then used to define expectations for prior distributions using a Markov chain Monte Carlo (MCMC) algorithm. A set of posterior means were defined in WinBUGS 1.4.3®. After the model had converged, samples from the conditional distributions were used to summarize the posterior distribution of the parameters. Thereafter, a spatial residual trend analyses was used to evaluate variance uncertainty propagation in the model using an autocovariance error matrix. Results By specifying coefficient estimates in a Bayesian framework, the covariate number of tillers was found to be a significant predictor, positively associated with An. arabiensis aquatic habitats. The spatial filter models accounted for approximately 19% redundant locational information in the ecological sampled An. arabiensis aquatic habitat data. In the residual error estimation model there was significant positive autocorrelation (i.e., clustering of habitats in geographic space) based on log-transformed larval/pupal data and the sampled covariate depth of habitat. Conclusion An autocorrelation error covariance matrix and a spatial filter analyses can prioritize mosquito control strategies by providing a computationally attractive and feasible description of variance uncertainty estimates for correctly identifying clusters of prolific An. arabiensis aquatic habitats based on larval/pupal productivity. PMID:19772590

Evaluation of normalization methods for cDNA microarray data by k-NN classification

PubMed Central

Wu, Wei; Xing, Eric P; Myers, Connie; Mian, I Saira; Bissell, Mina J

2005-01-01

Background Non-biological factors give rise to unwanted variations in cDNA microarray data. There are many normalization methods designed to remove such variations. However, to date there have been few published systematic evaluations of these techniques for removing variations arising from dye biases in the context of downstream, higher-order analytical tasks such as classification. Results Ten location normalization methods that adjust spatial- and/or intensity-dependent dye biases, and three scale methods that adjust scale differences were applied, individually and in combination, to five distinct, published, cancer biology-related cDNA microarray data sets. Leave-one-out cross-validation (LOOCV) classification error was employed as the quantitative end-point for assessing the effectiveness of a normalization method. In particular, a known classifier, k-nearest neighbor (k-NN), was estimated from data normalized using a given technique, and the LOOCV error rate of the ensuing model was computed. We found that k-NN classifiers are sensitive to dye biases in the data. Using NONRM and GMEDIAN as baseline methods, our results show that single-bias-removal techniques which remove either spatial-dependent dye bias (referred later as spatial effect) or intensity-dependent dye bias (referred later as intensity effect) moderately reduce LOOCV classification errors; whereas double-bias-removal techniques which remove both spatial- and intensity effect reduce LOOCV classification errors even further. Of the 41 different strategies examined, three two-step processes, IGLOESS-SLFILTERW7, ISTSPLINE-SLLOESS and IGLOESS-SLLOESS, all of which removed intensity effect globally and spatial effect locally, appear to reduce LOOCV classification errors most consistently and effectively across all data sets. We also found that the investigated scale normalization methods do not reduce LOOCV classification error. Conclusion Using LOOCV error of k-NNs as the evaluation criterion, three double-bias-removal normalization strategies, IGLOESS-SLFILTERW7, ISTSPLINE-SLLOESS and IGLOESS-SLLOESS, outperform other strategies for removing spatial effect, intensity effect and scale differences from cDNA microarray data. The apparent sensitivity of k-NN LOOCV classification error to dye biases suggests that this criterion provides an informative measure for evaluating normalization methods. All the computational tools used in this study were implemented using the R language for statistical computing and graphics. PMID:16045803

Evaluation of normalization methods for cDNA microarray data by k-NN classification.

PubMed

Wu, Wei; Xing, Eric P; Myers, Connie; Mian, I Saira; Bissell, Mina J

2005-07-26

Non-biological factors give rise to unwanted variations in cDNA microarray data. There are many normalization methods designed to remove such variations. However, to date there have been few published systematic evaluations of these techniques for removing variations arising from dye biases in the context of downstream, higher-order analytical tasks such as classification. Ten location normalization methods that adjust spatial- and/or intensity-dependent dye biases, and three scale methods that adjust scale differences were applied, individually and in combination, to five distinct, published, cancer biology-related cDNA microarray data sets. Leave-one-out cross-validation (LOOCV) classification error was employed as the quantitative end-point for assessing the effectiveness of a normalization method. In particular, a known classifier, k-nearest neighbor (k-NN), was estimated from data normalized using a given technique, and the LOOCV error rate of the ensuing model was computed. We found that k-NN classifiers are sensitive to dye biases in the data. Using NONRM and GMEDIAN as baseline methods, our results show that single-bias-removal techniques which remove either spatial-dependent dye bias (referred later as spatial effect) or intensity-dependent dye bias (referred later as intensity effect) moderately reduce LOOCV classification errors; whereas double-bias-removal techniques which remove both spatial- and intensity effect reduce LOOCV classification errors even further. Of the 41 different strategies examined, three two-step processes, IGLOESS-SLFILTERW7, ISTSPLINE-SLLOESS and IGLOESS-SLLOESS, all of which removed intensity effect globally and spatial effect locally, appear to reduce LOOCV classification errors most consistently and effectively across all data sets. We also found that the investigated scale normalization methods do not reduce LOOCV classification error. Using LOOCV error of k-NNs as the evaluation criterion, three double-bias-removal normalization strategies, IGLOESS-SLFILTERW7, ISTSPLINE-SLLOESS and IGLOESS-SLLOESS, outperform other strategies for removing spatial effect, intensity effect and scale differences from cDNA microarray data. The apparent sensitivity of k-NN LOOCV classification error to dye biases suggests that this criterion provides an informative measure for evaluating normalization methods. All the computational tools used in this study were implemented using the R language for statistical computing and graphics.

Impact of temporal upscaling and chemical transport model horizontal resolution on reducing ozone exposure misclassification

NASA Astrophysics Data System (ADS)

Xu, Yadong; Serre, Marc L.; Reyes, Jeanette M.; Vizuete, William

2017-10-01

We have developed a Bayesian Maximum Entropy (BME) framework that integrates observations from a surface monitoring network and predictions from a Chemical Transport Model (CTM) to create improved exposure estimates that can be resolved into any spatial and temporal resolution. The flexibility of the framework allows for input of data in any choice of time scales and CTM predictions of any spatial resolution with varying associated degrees of estimation error and cost in terms of implementation and computation. This study quantifies the impact on exposure estimation error due to these choices by first comparing estimations errors when BME relied on ozone concentration data either as an hourly average, the daily maximum 8-h average (DM8A), or the daily 24-h average (D24A). Our analysis found that the use of DM8A and D24A data, although less computationally intensive, reduced estimation error more when compared to the use of hourly data. This was primarily due to the poorer CTM model performance in the hourly average predicted ozone. Our second analysis compared spatial variability and estimation errors when BME relied on CTM predictions with a grid cell resolution of 12 × 12 km2 versus a coarser resolution of 36 × 36 km2. Our analysis found that integrating the finer grid resolution CTM predictions not only reduced estimation error, but also increased the spatial variability in daily ozone estimates by 5 times. This improvement was due to the improved spatial gradients and model performance found in the finer resolved CTM simulation. The integration of observational and model predictions that is permitted in a BME framework continues to be a powerful approach for improving exposure estimates of ambient air pollution. The results of this analysis demonstrate the importance of also understanding model performance variability and its implications on exposure error.

Impact of random pointing and tracking errors on the design of coherent and incoherent optical intersatellite communication links

NASA Technical Reports Server (NTRS)

Chen, Chien-Chung; Gardner, Chester S.

1989-01-01

Given the rms transmitter pointing error and the desired probability of bit error (PBE), it can be shown that an optimal transmitter antenna gain exists which minimizes the required transmitter power. Given the rms local oscillator tracking error, an optimum receiver antenna gain can be found which optimizes the receiver performance. The impact of pointing and tracking errors on the design of direct-detection pulse-position modulation (PPM) and heterodyne noncoherent frequency-shift keying (NCFSK) systems are then analyzed in terms of constraints on the antenna size and the power penalty incurred. It is shown that in the limit of large spatial tracking errors, the advantage in receiver sensitivity for the heterodyne system is quickly offset by the smaller antenna gain and the higher power penalty due to tracking errors. In contrast, for systems with small spatial tracking errors, the heterodyne system is superior because of the higher receiver sensitivity.

Rain radar measurement error estimation using data assimilation in an advection-based nowcasting system

NASA Astrophysics Data System (ADS)

Merker, Claire; Ament, Felix; Clemens, Marco

2017-04-01

The quantification of measurement uncertainty for rain radar data remains challenging. Radar reflectivity measurements are affected, amongst other things, by calibration errors, noise, blocking and clutter, and attenuation. Their combined impact on measurement accuracy is difficult to quantify due to incomplete process understanding and complex interdependencies. An improved quality assessment of rain radar measurements is of interest for applications both in meteorology and hydrology, for example for precipitation ensemble generation, rainfall runoff simulations, or in data assimilation for numerical weather prediction. Especially a detailed description of the spatial and temporal structure of errors is beneficial in order to make best use of the areal precipitation information provided by radars. Radar precipitation ensembles are one promising approach to represent spatially variable radar measurement errors. We present a method combining ensemble radar precipitation nowcasting with data assimilation to estimate radar measurement uncertainty at each pixel. This combination of ensemble forecast and observation yields a consistent spatial and temporal evolution of the radar error field. We use an advection-based nowcasting method to generate an ensemble reflectivity forecast from initial data of a rain radar network. Subsequently, reflectivity data from single radars is assimilated into the forecast using the Local Ensemble Transform Kalman Filter. The spread of the resulting analysis ensemble provides a flow-dependent, spatially and temporally correlated reflectivity error estimate at each pixel. We will present first case studies that illustrate the method using data from a high-resolution X-band radar network.

A method to map errors in the deformable registration of 4DCT images1

PubMed Central

Vaman, Constantin; Staub, David; Williamson, Jeffrey; Murphy, Martin J.

2010-01-01

Purpose: To present a new approach to the problem of estimating errors in deformable image registration (DIR) applied to sequential phases of a 4DCT data set. Methods: A set of displacement vector fields (DVFs) are made by registering a sequence of 4DCT phases. The DVFs are assumed to display anatomical movement, with the addition of errors due to the imaging and registration processes. The positions of physical landmarks in each CT phase are measured as ground truth for the physical movement in the DVF. Principal component analysis of the DVFs and the landmarks is used to identify and separate the eigenmodes of physical movement from the error eigenmodes. By subtracting the physical modes from the principal components of the DVFs, the registration errors are exposed and reconstructed as DIR error maps. The method is demonstrated via a simple numerical model of 4DCT DVFs that combines breathing movement with simulated maps of spatially correlated DIR errors. Results: The principal components of the simulated DVFs were observed to share the basic properties of principal components for actual 4DCT data. The simulated error maps were accurately recovered by the estimation method. Conclusions: Deformable image registration errors can have complex spatial distributions. Consequently, point-by-point landmark validation can give unrepresentative results that do not accurately reflect the registration uncertainties away from the landmarks. The authors are developing a method for mapping the complete spatial distribution of DIR errors using only a small number of ground truth validation landmarks. PMID:21158288

Spatial regression methods capture prediction uncertainty in species distribution model projections through time

Treesearch

Alan K. Swanson; Solomon Z. Dobrowski; Andrew O. Finley; James H. Thorne; Michael K. Schwartz

2013-01-01

The uncertainty associated with species distribution model (SDM) projections is poorly characterized, despite its potential value to decision makers. Error estimates from most modelling techniques have been shown to be biased due to their failure to account for spatial autocorrelation (SAC) of residual error. Generalized linear mixed models (GLMM) have the ability to...

Self-error-rejecting photonic qubit transmission in polarization-spatial modes with linear optical elements

NASA Astrophysics Data System (ADS)

Jiang, YuXiao; Guo, PengLiang; Gao, ChengYan; Wang, HaiBo; Alzahrani, Faris; Hobiny, Aatef; Deng, FuGuo

2017-12-01

We present an original self-error-rejecting photonic qubit transmission scheme for both the polarization and spatial states of photon systems transmitted over collective noise channels. In our scheme, we use simple linear-optical elements, including half-wave plates, 50:50 beam splitters, and polarization beam splitters, to convert spatial-polarization modes into different time bins. By using postselection in different time bins, the success probability of obtaining the uncorrupted states approaches 1/4 for single-photon transmission, which is not influenced by the coefficients of noisy channels. Our self-error-rejecting transmission scheme can be generalized to hyperentangled n-photon systems and is useful in practical high-capacity quantum communications with photon systems in two degrees of freedom.

A parametric multiclass Bayes error estimator for the multispectral scanner spatial model performance evaluation

NASA Technical Reports Server (NTRS)

Mobasseri, B. G.; Mcgillem, C. D.; Anuta, P. E. (Principal Investigator)

1978-01-01

The author has identified the following significant results. The probability of correct classification of various populations in data was defined as the primary performance index. The multispectral data being of multiclass nature as well, required a Bayes error estimation procedure that was dependent on a set of class statistics alone. The classification error was expressed in terms of an N dimensional integral, where N was the dimensionality of the feature space. The multispectral scanner spatial model was represented by a linear shift, invariant multiple, port system where the N spectral bands comprised the input processes. The scanner characteristic function, the relationship governing the transformation of the input spatial, and hence, spectral correlation matrices through the systems, was developed.

The use of far infra-red radiation for the detection of concealed metal objects.

DOT National Transportation Integrated Search

1971-11-01

The use of infra-red radiation for the detection : of conceal ed metal objects has been investiga ted both : theoretically and experimentally. The investigation was : divided into two phases, one which considered passive : techniques, and another whi...

New capability for hazardous materials ID within sealed containers using a portable spatially offset Raman spectroscopy (SORS) device

NASA Astrophysics Data System (ADS)

Stokes, Robert J.; Bailey, Mike; Bonthron, Stuart; Stone, Thomas; Maskall, Guy; Presly, Oliver; Roy, Eric; Tombling, Craig; Loeffen, Paul W.

2016-10-01

Raman spectroscopy allows the acquisition of molecularly specific signatures of pure compounds and mixtures making it a popular method for material identification applications. In hazardous materials, security and counter terrorism applications, conventional handheld Raman systems are typically limited to operation by line-of-sight or through relatively transparent plastic bags / clear glass vials. If materials are concealed behind thicker, coloured or opaque barriers it can be necessary to open and take a sample. Spatially Offset Raman Spectroscopy (SORS)[1] is a novel variant of Raman spectroscopy whereby multiple measurements at differing positions are used to separate the spectrum arising from the sub layers of a sample from the spectrum at the surface. For the first time, a handheld system based on SORS has been developed and applied to hazardous materials identification. The system - "Resolve" - enables new capabilities in the rapid identification of materials concealed by a wide variety of non-metallic sealed containers such as; coloured and opaque plastics, paper, card, sacks, fabric and glass. The range of potential target materials includes toxic industrial chemicals, explosives, narcotics, chemical warfare agents and biological materials. Resolve has the potential to improve the safety, efficiency and critical decision making in incident management, search operations, policing and ports and border operations. The operator is able to obtain a positive identification of a potentially hazardous material without opening or disturbing the container - to gain access to take a sample - thus improving safety. The technique is fast and simple thus suit and breathing gear time is used more efficiently. SORS also allows Raman to be deployed at an earlier stage in an event before more intrusive techniques are used. Evidential information is preserved and the chain of custody protected. Examples of detection capability for a number of materials and barrier types are presented below.

'I am doing fine only because I have not told anyone': the necessity of concealment in the lives of people living with HIV in India.

PubMed

George, Mathew Sunil; Lambert, Helen

2015-01-01

In HIV prevention and care programmes, disclosure of status by HIV-positive individuals is generally encouraged to contain the infection and provide adequate support to the person concerned. Lack of disclosure is generally framed as a barrier to preventive behaviours and accessing support. The assumption that disclosure is beneficial is also reflected in studies that aim to identify determinants of disclosure and recommend individual-level measures to promote disclosure. However, in contexts where HIV infection is stigmatised and there is fear of rejection and discrimination among those living with HIV, concealment of status becomes a way to try and regain as much as possible the life that was disrupted by the discovery of HIV infection. In this study of HIV-positive women and children in India, concealment was considered essential by individuals and families of those living with HIV to re-establish and maintain their normal lives in an environment where stigma and discrimination were prevalent. This paper describes why women and care givers of children felt the need to conceal HIV status, the various ways in which people tried to do so and the implications for treatment of people living with HIV. We found that while women were generally willing to disclose their status to their husband or partner, they were very keen to conceal their status from all others, including family members. Parents and carers with an HIV-positive child were not willing to disclose this status to the child or to others. Understanding the different rationales for concealment would help policy makers and programme managers to develop more appropriate care management strategies and train care providers to assist clients in accessing care and support without disrupting their lives.

‘I am doing fine only because I have not told anyone’: the necessity of concealment in the lives of people living with HIV in India

PubMed Central

George, Mathew Sunil; Lambert, Helen

2015-01-01

In HIV prevention and care programmes, disclosure of status by HIV-positive individuals is generally encouraged to contain the infection and provide adequate support to the person concerned. Lack of disclosure is generally framed as a barrier to preventive behaviours and accessing support. The assumption that disclosure is beneficial is also reflected in studies that aim to identify determinants of disclosure and recommend individual-level measures to promote disclosure. However, in contexts where HIV infection is stigmatised and there is fear of rejection and discrimination among those living with HIV, concealment of status becomes a way to try and regain as much as possible the life that was disrupted by the discovery of HIV infection. In this study of HIV-positive women and children in India, concealment was considered essential by individuals and families of those living with HIV to re-establish and maintain their normal lives in an environment where stigma and discrimination were prevalent. This paper describes why women and care givers of children felt the need to conceal HIV status, the various ways in which people tried to do so and the implications for treatment of people living with HIV. We found that while women were generally willing to disclose their status to their husband or partner, they were very keen to conceal their status from all others, including family members. Parents and carers with an HIV-positive child were not willing to disclose this status to the child or to others. Understanding the different rationales for concealment would help policy makers and programme managers to develop more appropriate care management strategies and train care providers to assist clients in accessing care and support without disrupting their lives. PMID:25706959

Injury reporting rates and injury concealment patterns differ between high-school cirque performers and basketball players.

PubMed

Long, Ashley S; Ambegaonkar, Jatin P; Fahringer, Patty M

2011-12-01

The performing arts style of cirque has grown in popularity, with high-school participants increasingly practicing this style. Still, little research has examined the injury reporting rates and patterns in this population. Our study aimed to compare injury reporting rates and injury concealment patterns between high-school cirque performers and a peer-group of basketball players. Fifty participants (30 cirque, 20 basketball) completed a 12-item injury history and concealment instrument with chi-squared analyses and Fisher's exact tests comparing groups (p = 0.05). While no group differences (p = 0.36) existed in injuries reported, basketball players were more likely (p = 0.01) to miss participation due to injury than cirque performers. No significant difference existed between participants regarding which healthcare provider they reported to first (p = 0.27), but basketball players reported their injuries to the athletic trainer at higher rates (50%) than cirque performers (20%). A nonsignificant trend (p = 0.08) was noted in promptness to report injury, with more cirque performers (13%) concealing their injuries than basketball players (5%). Several reasons were noted for concealment of injury, with the most common being the belief that the injury would "go away" on its own. Knee injuries were most common in basketball players (23.7%) and back and knee injuries (10.5% each) in cirque performers. Despite similar injury rates, cirque participants concealed injuries more than peer-basketball players. Reasons may include losing performance roles, unfamiliarity and low trust with healthcare providers, ignorance about initially minor-looking injuries, and higher pain tolerance thresholds. Education and communication are essential to allow performing artists to seek healthcare support. Research is needed to appropriately understand and meet the needs of this underserved performing artist population.

The need for randomization in animal trials: an overview of systematic reviews.

PubMed

Hirst, Jennifer A; Howick, Jeremy; Aronson, Jeffrey K; Roberts, Nia; Perera, Rafael; Koshiaris, Constantinos; Heneghan, Carl

2014-01-01

Randomization, allocation concealment, and blind outcome assessment have been shown to reduce bias in human studies. Authors from the Collaborative Approach to Meta Analysis and Review of Animal Data from Experimental Studies (CAMARADES) collaboration recently found that these features protect against bias in animal stroke studies. We extended the scope the work from CAMARADES to include investigations of treatments for any condition. We conducted an overview of systematic reviews. We searched Medline and Embase for systematic reviews of animal studies testing any intervention (against any control) and we included any disease area and outcome. We included reviews comparing randomized versus not randomized (but otherwise controlled), concealed versus unconcealed treatment allocation, or blinded versus unblinded outcome assessment. Thirty-one systematic reviews met our inclusion criteria: 20 investigated treatments for experimental stroke, 4 reviews investigated treatments for spinal cord diseases, while 1 review each investigated treatments for bone cancer, intracerebral hemorrhage, glioma, multiple sclerosis, Parkinson's disease, and treatments used in emergency medicine. In our sample 29% of studies reported randomization, 15% of studies reported allocation concealment, and 35% of studies reported blinded outcome assessment. We pooled the results in a meta-analysis, and in our primary analysis found that failure to randomize significantly increased effect sizes, whereas allocation concealment and blinding did not. In our secondary analyses we found that randomization, allocation concealment, and blinding reduced effect sizes, especially where outcomes were subjective. Our study demonstrates the need for randomization, allocation concealment, and blind outcome assessment in animal research across a wide range of outcomes and disease areas. Since human studies are often justified based on results from animal studies, our results suggest that unduly biased animal studies should not be allowed to constitute part of the rationale for human trials.

Geophysical and geochemical data from the area of the Pebble Cu-Au-Mo porphyry deposit, southwestern Alaska: Contributions to assessment techniques for concealed mineral resources

USGS Publications Warehouse

Anderson, E.D.; Smith, S.M.; Giles, S.A.; Granitto, Matthew; Eppinger, R.G.; Bedrosian, P.A.; Shah, A.K.; Kelley, K.D.; Fey, D.L.; Minsley, B.J.; Brown, P.J.

2011-01-01

In 2007, the U.S. Geological Survey began a multidisciplinary study in southwest Alaska to investigate the setting and detectability of mineral deposits in concealed volcanic and glacial terranes. The study area hosts the world-class Pebble porphyry Cu-Au-Mo deposit, and through collaboration with the Pebble Limited Partnership, a range of geophysical and geochemical investigations was carried out in proximity to the deposit. The deposit is almost entirely concealed by tundra, glacial deposits, and post-mineralization volcanic rocks. The discovery of mineral resources beneath cover is becoming more important because most of the mineral resources at the surface have already been discovered. Research is needed to identify ways in which to assess for concealed mineral resources. This report presents the uninterpreted geophysical measurements and geochemical and mineralogical analytical data from samples collected during the summer field seasons from 2007 to 2010, and makes the data available in a single Geographic Information System (GIS) database.

The inconspicuous penis in children.

PubMed

Cimador, Marcello; Catalano, Pieralba; Ortolano, Rita; Giuffrè, Mario

2015-04-01

The term 'inconspicuous penis' refers to a group of anatomical abnormalities in which the penis looks smaller than is expected. Micropenis can be defined as 'true micropenis'--which results from a defect in the hypothalamic-pituitary-gonadal axis--and 'micropenis secondary to congenital anatomical anomalies of the surrounding and overlying structures'--also known as 'concealed penis'. The different forms of concealed penis include webbed penis, congenital megaprepuce and partially hidden penis caused by prepubic adiposity. This disorder can also have iatrogenic causes resulting from adhesions that are secondary to circumcision--this type of concealed penis is known as 'trapped penis'. However, in both groups, micropenis is defined as a stretched penile length that is at least 2.5 SD below the mean for the patient's age, but without any other penile defects. Patients with true micropenis can be managed with testosterone, which has demonstrated good penile elongation results in the long term. Surgery also has a pivotal role in reconstruction for elongating the penis and for correction of anatomical abnormalities in concealed penis.

Spatially coupled low-density parity-check error correction for holographic data storage

NASA Astrophysics Data System (ADS)

Ishii, Norihiko; Katano, Yutaro; Muroi, Tetsuhiko; Kinoshita, Nobuhiro

2017-09-01

The spatially coupled low-density parity-check (SC-LDPC) was considered for holographic data storage. The superiority of SC-LDPC was studied by simulation. The simulations show that the performance of SC-LDPC depends on the lifting number, and when the lifting number is over 100, SC-LDPC shows better error correctability compared with irregular LDPC. SC-LDPC is applied to the 5:9 modulation code, which is one of the differential codes. The error-free point is near 2.8 dB and over 10-1 can be corrected in simulation. From these simulation results, this error correction code can be applied to actual holographic data storage test equipment. Results showed that 8 × 10-2 can be corrected, furthermore it works effectively and shows good error correctability.

Spatial averaging errors in creating hemispherical reflectance (albedo) maps from directional reflectance data

NASA Technical Reports Server (NTRS)

Kimes, D. S.; Kerber, A. G.; Sellers, P. J.

1993-01-01

Spatial averaging errors which may occur when creating hemispherical reflectance maps for different cover types from direct nadir technique to estimate the hemispherical reflectance are assessed by comparing the results with those obtained with a knowledge-based system called VEG (Kimes et al., 1991, 1992). It was found that hemispherical reflectance errors provided by using VEG are much less than those using the direct nadir techniques, depending on conditions. Suggestions are made concerning sampling and averaging strategies for creating hemispherical reflectance maps for photosynthetic, carbon cycle, and climate change studies.

High spatial precision nano-imaging of polarization-sensitive plasmonic particles

NASA Astrophysics Data System (ADS)

Liu, Yunbo; Wang, Yipei; Lee, Somin Eunice

2018-02-01

Precise polarimetric imaging of polarization-sensitive nanoparticles is essential for resolving their accurate spatial positions beyond the diffraction limit. However, conventional technologies currently suffer from beam deviation errors which cannot be corrected beyond the diffraction limit. To overcome this issue, we experimentally demonstrate a spatially stable nano-imaging system for polarization-sensitive nanoparticles. In this study, we show that by integrating a voltage-tunable imaging variable polarizer with optical microscopy, we are able to suppress beam deviation errors. We expect that this nano-imaging system should allow for acquisition of accurate positional and polarization information from individual nanoparticles in applications where real-time, high precision spatial information is required.

Sensitivity and specificity of CT scanning for determining the number of internally concealed packages in 'body-packers'.

PubMed

Asha, Stephen Edward; Higham, Matthew; Child, Peter

2015-05-01

If package counts on abdominal CTs of body-packers were known to be accurate, follow-up CTs could be avoided. The objective was to determine the accuracy of CT for the number of concealed packages in body-packers, and the reliability of package counts reported by body-packers who admit to concealing drugs. Suspected body-packers were identified from the emergency departments (ED) database. The medical record and radiology reports were reviewed for package counts determined by CT, patient-reported and physically retrieved. The last method was used as the reference standard. Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were calculated for CT package count accuracy. Reliability of patient-reported package counts was assessed using Pearson's correlation coefficient. There were 50 confirmed body-packers on whom 104 CT scans were performed. Data for the index and reference tests were available for 84 scans. The sensitivity, specificity, PPV and NPV for CT package count were 63% (95% CI 46% to 77%), 82% (95% CI 67% to 92%), 76% (95% CI 58% to 89%) and 71% (95% CI 56% to 83%) respectively. For CTs with a package count<15, the sensitivity, specificity, PPV and NPV for CT package count were 96% (95% CI 80% to 99%), 95% (95% CI 82% to 99%), 93% (95% CI 76% to 99%) and 97% (95% CI 86% to 100%), respectively. Correlation between patient-reported package counts and the number of packages retrieved was high (r=0.90, p<0.001, R2=81%). The accuracy of CT for determining the number of concealed packages is poor, although when applied to patients with few concealed packages accuracy is high and is useful as a rule-out test. Among patients who have admitted to drug concealment, the number of packages reported to be concealed is reliable. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Spatial effects, sampling errors, and task specialization in the honey bee.

PubMed

Johnson, B R

2010-05-01

Task allocation patterns should depend on the spatial distribution of work within the nest, variation in task demand, and the movement patterns of workers, however, relatively little research has focused on these topics. This study uses a spatially explicit agent based model to determine whether such factors alone can generate biases in task performance at the individual level in the honey bees, Apis mellifera. Specialization (bias in task performance) is shown to result from strong sampling error due to localized task demand, relatively slow moving workers relative to nest size, and strong spatial variation in task demand. To date, specialization has been primarily interpreted with the response threshold concept, which is focused on intrinsic (typically genotypic) differences between workers. Response threshold variation and sampling error due to spatial effects are not mutually exclusive, however, and this study suggests that both contribute to patterns of task bias at the individual level. While spatial effects are strong enough to explain some documented cases of specialization; they are relatively short term and not explanatory for long term cases of specialization. In general, this study suggests that the spatial layout of tasks and fluctuations in their demand must be explicitly controlled for in studies focused on identifying genotypic specialists.

The "double life" of bulimia: patients' experiences in daily life interactions.

PubMed

Pettersen, Gunn; Rosenvinge, Jan H; Ytterhus, Borgunn

2008-01-01

This qualitative study, using interviews with 38 subjects, explored how and why they conceal bulimic symptoms and the understanding of concealing in terms of social interaction. A "double life" was described as a dichotomy between being active and outgoing versus performing shameful bulimic behaviors and constantly living with fear of stigmatization, and striving against exposure. Concealing was well planned to avoid such fear, and to preserve dignity. Bulimia may be understood as volitional exertion of interaction control, not just as a result of poor impulse regulation. Understanding the meaning of secrecy and "double life" may facilitate help seeking behavior and guide treatment.

Audio-magnetotelluric survey to characterize the Sunnyside porphyry copper system in the Patagonia Mountains, Arizona

USGS Publications Warehouse

Sampson, Jay A.; Rodriguez, Brian D.

2010-01-01

The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size, resistivity, and skin depth of the polarizable mineral deposit concealed beneath thick overburden, a regional east-west audio-magnetotelluric sounding profile was acquired. The purpose of this report is to release the audio-magnetotelluric sounding data collected along that east-west profile. No interpretation of the data is included.

Detection and identification of concealed weapons using matrix pencil

NASA Astrophysics Data System (ADS)

Adve, Raviraj S.; Thayaparan, Thayananthan

2011-06-01

The detection and identification of concealed weapons is an extremely hard problem due to the weak signature of the target buried within the much stronger signal from the human body. This paper furthers the automatic detection and identification of concealed weapons by proposing the use of an effective approach to obtain the resonant frequencies in a measurement. The technique, based on Matrix Pencil, a scheme for model based parameter estimation also provides amplitude information, hence providing a level of confidence in the results. Of specific interest is the fact that Matrix Pencil is based on a singular value decomposition, making the scheme robust against noise.

Reducing representativeness and sampling errors in radio occultation-radiosonde comparisons

NASA Astrophysics Data System (ADS)

Gilpin, Shay; Rieckh, Therese; Anthes, Richard

2018-05-01

Radio occultation (RO) and radiosonde (RS) comparisons provide a means of analyzing errors associated with both observational systems. Since RO and RS observations are not taken at the exact same time or location, temporal and spatial sampling errors resulting from atmospheric variability can be significant and inhibit error analysis of the observational systems. In addition, the vertical resolutions of RO and RS profiles vary and vertical representativeness errors may also affect the comparison. In RO-RS comparisons, RO observations are co-located with RS profiles within a fixed time window and distance, i.e. within 3-6 h and circles of radii ranging between 100 and 500 km. In this study, we first show that vertical filtering of RO and RS profiles to a common vertical resolution reduces representativeness errors. We then test two methods of reducing horizontal sampling errors during RO-RS comparisons: restricting co-location pairs to within ellipses oriented along the direction of wind flow rather than circles and applying a spatial-temporal sampling correction based on model data. Using data from 2011 to 2014, we compare RO and RS differences at four GCOS Reference Upper-Air Network (GRUAN) RS stations in different climatic locations, in which co-location pairs were constrained to a large circle ( ˜ 666 km radius), small circle ( ˜ 300 km radius), and ellipse parallel to the wind direction ( ˜ 666 km semi-major axis, ˜ 133 km semi-minor axis). We also apply a spatial-temporal sampling correction using European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim) gridded data. Restricting co-locations to within the ellipse reduces root mean square (RMS) refractivity, temperature, and water vapor pressure differences relative to RMS differences within the large circle and produces differences that are comparable to or less than the RMS differences within circles of similar area. Applying the sampling correction shows the most significant reduction in RMS differences, such that RMS differences are nearly identical to the sampling correction regardless of the geometric constraints. We conclude that implementing the spatial-temporal sampling correction using a reliable model will most effectively reduce sampling errors during RO-RS comparisons; however, if a reliable model is not available, restricting spatial comparisons to within an ellipse parallel to the wind flow will reduce sampling errors caused by horizontal atmospheric variability.

Decreased Leftward ‘Aiming’ Motor-Intentional Spatial Cuing in Traumatic Brain Injury

PubMed Central

Wagner, Daymond; Eslinger, Paul J.; Barrett, A. M.

2016-01-01

Objective To characterize the mediation of attention and action in space following traumatic brain injury (TBI). Method Two exploratory analyses were performed to determine the influence of spatial ‘Aiming’ motor versus spatial ‘Where’ bias on line bisection in TBI participants. The first experiment compared performance according to severity and location of injury in TBI. The second experiment examined bisection performance in a larger TBI sample against a matched control group. In both experiments, participants bisected lines in near and far space using an apparatus that allowed for the fractionation of spatial Aiming versus Where error components. Results In the first experiment, participants with severe injuries tended to incur rightward error when starting from the right in far space, compared with participants with mild injuries. In the second experiment, when performance was examined at the individual level, more participants with TBI tended to incur rightward motor error compared to controls. Conclusions TBI may cause frontal-subcortical cognitive dysfunction and asymmetric motor perseveration, affecting spatial Aiming bias on line bisection. Potential effects on real-world function need further investigation. PMID:27571220

Language-specific dysgraphia in Korean patients with right brain stroke: influence of unilateral spatial neglect.

PubMed

Jang, Dae-Hyun; Kim, Min-Wook; Park, Kyoung Ha; Lee, Jae Woo

2015-03-01

The purpose of the present study was to investigate the relationship between Korean language-specific dysgraphia and unilateral spatial neglect in 31 right brain stroke patients. All patients were tested for writing errors in spontaneous writing, dictation, and copying tests. The dysgraphia was classified into visuospatial omission, visuospatial destruction, syllabic tilting, stroke omission, stroke addition, and stroke tilting. Twenty-three (77.4%) of the 31 patients made dysgraphia and 18 (58.1%) demonstrated unilateral spatial neglect. The visuospatial omission was the most common dysgraphia followed by stroke addition and omission errors. The highest number of errors was made in the copying and the least was in the spontaneous writing test. Patients with unilateral spatial neglect made a significantly higher number of dysgraphia in the copying test than those without. We identified specific dysgraphia features such as a right side space omission and a vertical stroke addition in Korean right brain stroke patients. In conclusion, unilateral spatial neglect influences copy writing system of Korean language in patients with right brain stroke.

Rotational wind indicator enhances control of rotated displays

NASA Technical Reports Server (NTRS)

Cunningham, H. A.; Pavel, Misha

1991-01-01

Rotation by 108 deg of the spatial mapping between a visual display and a manual input device produces large spatial errors in a discrete aiming task. These errors are not easily corrected by voluntary mental effort, but the central nervous system does adapt gradually to the new mapping. Bernotat (1970) showed that adding true hand position to a 90 deg rotated display improved performance of a compensatory tracking task, but tracking error rose again upon removal of the explicit cue. This suggests that the explicit error signal did not induce changes in the neural mapping, but rather allowed the operator to reduce tracking error using a higher mental strategy. In this report, we describe an explicit visual display enhancement applied to a 108 deg rotated discrete aiming task. A 'wind indicator' corresponding to the effect of the mapping rotation is displayed on the operator-controlled cursor. The human operator is instructed to oppose the virtual force represented by the indicator, as one would do if flying an airplane in a crosswind. This enhancement reduces spatial aiming error in the first 10 minutes of practice by an average of 70 percent when compared to a no enhancement control condition. Moreover, it produces adaptation aftereffect, which is evidence of learning by neural adaptation rather than by mental strategy. Finally, aiming error does not rise upon removal of the explicit cue.

College Students' Reasons for Concealing Suicidal Ideation

ERIC Educational Resources Information Center

Burton Denmark, Adryon; Hess, Elaine; Becker, Martin Swanbrow

2012-01-01

Self-reported reasons for concealing suicidal ideation were explored using data from a national survey of undergraduate and graduate students: 558 students indicated that they seriously considered attempting suicide during the previous year and did not tell anyone about their suicidal thoughts. Content analysis of students' qualitative responses…

Behavioral Indicators of Legal and Illegal Gun Carrying

DTIC Science & Technology

2015-05-01

wide variety of handguns , in a wide variety of sizes and shapes, made of a wide variety of materials , and this variation is likely to have a subtle...Under Clothing/Belt ..................................................................................................... 23 Concealment of Handgun ...in Center of Chest ..................................................................................... 24 Concealment of Handgun in Groin Area with

An interfering Go/No-go task does not affect accuracy in a Concealed Information Test.

PubMed

Ambach, Wolfgang; Stark, Rudolf; Peper, Martin; Vaitl, Dieter

2008-04-01

Following the idea that response inhibition processes play a central role in concealing information, the present study investigated the influence of a Go/No-go task as an interfering mental activity, performed parallel to the Concealed Information Test (CIT), on the detectability of concealed information. 40 undergraduate students participated in a mock-crime experiment and simultaneously performed a CIT and a Go/No-go task. Electrodermal activity (EDA), respiration line length (RLL), heart rate (HR) and finger pulse waveform length (FPWL) were registered. Reaction times were recorded as behavioral measures in the Go/No-go task as well as in the CIT. As a within-subject control condition, the CIT was also applied without an additional task. The parallel task did not influence the mean differences of the physiological measures of the mock-crime-related probe and the irrelevant items. This finding might possibly be due to the fact that the applied parallel task induced a tonic rather than a phasic mental activity, which did not influence differential responding to CIT items. No physiological evidence for an interaction between the parallel task and sub-processes of deception (e.g. inhibition) was found. Subjects' performance in the Go/No-go parallel task did not contribute to the detection of concealed information. Generalizability needs further investigations of different variations of the parallel task.

A non-imaging polarized terahertz passive system for detecting and identifying concealed explosives

NASA Astrophysics Data System (ADS)

Karam, Mostafa A.; Meyer, Doug

2011-06-01

Existing terahertz THz systems for detecting concealed explosives are not capable of identifying explosive type which leads to higher false alarm rates. Moreover, some of those systems are imaging systems that invade personal privacy, and require more processing and computational resources. Other systems have no polarization preference which makes them incapable of capturing the geometric features of an explosive. In this study a non-imaging polarized THz passive system for detecting and identifying concealed explosives overcoming the forgoing shortcomings is developed. The system employs a polarized passive THz sensor in acquiring emitted data from a scene that may have concealed explosives. The acquired data are decomposed into their natural resonance frequencies, and the number of those frequencies is used as criteria in detecting the explosive presence. If the presence of an explosive is confirmed, a set of physically based retrieval algorithms is used in extracting the explosive dielectric constant/refractive index value from natural resonance frequencies and amplitudes of associated signals. Comparing the refractive index value against a database of refractive indexes of known explosives identifies the explosive type. As an application, a system having a dual polarized radiometer operating within the frequency band of 0.62- 0.82 THz is presented and used in detecting and identifying person borne C-4 explosive concealed under a cotton garment. The system showed higher efficiencies in detecting and identifying the explosive.

Anxiety and Related Disorders and Concealment in Sexual Minority Young Adults.

PubMed

Cohen, Jeffrey M; Blasey, Christine; Barr Taylor, C; Weiss, Brandon J; Newman, Michelle G

2016-01-01

Sexual minorities face greater exposure to discrimination and rejection than heterosexuals. Given these threats, sexual minorities may engage in sexual orientation concealment in order to avoid danger. This social stigma and minority stress places sexual minorities at risk for anxiety and related disorders. Given that three fourths of anxiety disorder onset occurs before the age of 24, the current study investigated the symptoms of generalized anxiety disorder, social phobia, panic disorder, posttraumatic stress disorder, and depression in sexual minority young adults relative to their heterosexual peers. Secondarily, the study investigated sexual orientation concealment as a predictor of anxiety and related disorders. A sample of 157 sexual minority and 157 heterosexual young adults matched on age and gender completed self-report measures of the aforementioned disorders, and indicated their level of sexual orientation concealment. Results revealed that sexual minority young adults reported greater symptoms relative to heterosexuals across all outcome measures. There were no interactions between sexual minority status and gender, however, women had higher symptoms across all disorders. Sexual minority young women appeared to be at the most risk for clinical levels of anxiety and related disorders. In addition, concealment of sexual orientation significantly predicted symptoms of social phobia. Implications are offered for the cognitive and behavioral treatment of anxiety and related disorders in this population. Copyright © 2015. Published by Elsevier Ltd.

Spatial Dynamics and Determinants of County-Level Education Expenditure in China

ERIC Educational Resources Information Center

Gu, Jiafeng

2012-01-01

In this paper, a multivariate spatial autoregressive model of local public education expenditure determination with autoregressive disturbance is developed and estimated. The existence of spatial interdependence is tested using Moran's I statistic and Lagrange multiplier test statistics for both the spatial error and spatial lag models. The full…

Spatial serial order processing in schizophrenia.

PubMed

Fraser, David; Park, Sohee; Clark, Gina; Yohanna, Daniel; Houk, James C

2004-10-01

The aim of this study was to examine serial order processing deficits in 21 schizophrenia patients and 16 age- and education-matched healthy controls. In a spatial serial order working memory task, one to four spatial targets were presented in a randomized sequence. Subjects were required to remember the locations and the order in which the targets were presented. Patients showed a marked deficit in ability to remember the sequences compared with controls. Increasing the number of targets within a sequence resulted in poorer memory performance for both control and schizophrenia subjects, but the effect was much more pronounced in the patients. Targets presented at the end of a long sequence were more vulnerable to memory error in schizophrenia patients. Performance deficits were not attributable to motor errors, but to errors in target choice. The results support the idea that the memory errors seen in schizophrenia patients may be due to saturating the working memory network at relatively low levels of memory load.

Aging and the intrusion superiority effect in visuo-spatial working memory.

PubMed

Cornoldi, Cesare; Bassani, Chiara; Berto, Rita; Mammarella, Nicola

2007-01-01

This study investigated the active component of visuo-spatial working memory (VSWM) in younger and older adults testing the hypotheses that elderly individuals have a poorer performance than younger ones and that errors in active VSWM tasks depend, at least partially, on difficulties in avoiding intrusions (i.e., avoiding already activated information). In two experiments, participants were presented with sequences of matrices on which three positions were pointed out sequentially: their task was to process all the positions but indicate only the final position of each sequence. Results showed a poorer performance in the elderly compared to the younger group and a higher number of intrusion (errors due to activated but irrelevant positions) rather than invention (errors consisting of pointing out a position never indicated by the experiementer) errors. The number of errors increased when a concurrent task was introduced (Experiment 1) and it was affected by different patterns of matrices (Experiment 2). In general, results show that elderly people have an impaired VSWM and produce a large number of errors due to inhibition failures. However, both the younger and the older adults' visuo-spatial working memory was affected by the presence of activated irrelevant information, the reduction of the available resources, and task constraints.

Visualizing Uncertainty of Point Phenomena by Redesigned Error Ellipses

NASA Astrophysics Data System (ADS)

Murphy, Christian E.

2018-05-01

Visualizing uncertainty remains one of the great challenges in modern cartography. There is no overarching strategy to display the nature of uncertainty, as an effective and efficient visualization depends, besides on the spatial data feature type, heavily on the type of uncertainty. This work presents a design strategy to visualize uncertainty con-nected to point features. The error ellipse, well-known from mathematical statistics, is adapted to display the uncer-tainty of point information originating from spatial generalization. Modified designs of the error ellipse show the po-tential of quantitative and qualitative symbolization and simultaneous point based uncertainty symbolization. The user can intuitively depict the centers of gravity, the major orientation of the point arrays as well as estimate the ex-tents and possible spatial distributions of multiple point phenomena. The error ellipse represents uncertainty in an intuitive way, particularly suitable for laymen. Furthermore it is shown how applicable an adapted design of the er-ror ellipse is to display the uncertainty of point features originating from incomplete data. The suitability of the error ellipse to display the uncertainty of point information is demonstrated within two showcases: (1) the analysis of formations of association football players, and (2) uncertain positioning of events on maps for the media.

Distributed optical fiber-based monitoring approach of spatial seepage behavior in dike engineering

NASA Astrophysics Data System (ADS)

Su, Huaizhi; Ou, Bin; Yang, Lifu; Wen, Zhiping

2018-07-01

The failure caused by seepage is the most common one in dike engineering. As to the characteristics of seepage in dike, such as longitudinal extension engineering, the randomness, strong concealment and small initial quantity order, by means of distributed fiber temperature sensor system (DTS), adopting an improved optical fiber layer layout scheme, the location of initial interpolation point of the saturation line is obtained. With the barycentric Lagrange interpolation collocation method (BLICM), the infiltrated surface of dike full-section is generated. Combined with linear optical fiber monitoring seepage method, BLICM is applied in an engineering case, which shows that a real-time seepage monitoring technique is presented in full-section of dike based on the combination method.

A spatial error model with continuous random effects and an application to growth convergence

NASA Astrophysics Data System (ADS)

Laurini, Márcio Poletti

2017-10-01

We propose a spatial error model with continuous random effects based on Matérn covariance functions and apply this model for the analysis of income convergence processes (β -convergence). The use of a model with continuous random effects permits a clearer visualization and interpretation of the spatial dependency patterns, avoids the problems of defining neighborhoods in spatial econometrics models, and allows projecting the spatial effects for every possible location in the continuous space, circumventing the existing aggregations in discrete lattice representations. We apply this model approach to analyze the economic growth of Brazilian municipalities between 1991 and 2010 using unconditional and conditional formulations and a spatiotemporal model of convergence. The results indicate that the estimated spatial random effects are consistent with the existence of income convergence clubs for Brazilian municipalities in this period.

Loss tolerant speech decoder for telecommunications

NASA Technical Reports Server (NTRS)

Prieto, Jr., Jaime L. (Inventor)

1999-01-01

A method and device for extrapolating past signal-history data for insertion into missing data segments in order to conceal digital speech frame errors. The extrapolation method uses past-signal history that is stored in a buffer. The method is implemented with a device that utilizes a finite-impulse response (FIR) multi-layer feed-forward artificial neural network that is trained by back-propagation for one-step extrapolation of speech compression algorithm (SCA) parameters. Once a speech connection has been established, the speech compression algorithm device begins sending encoded speech frames. As the speech frames are received, they are decoded and converted back into speech signal voltages. During the normal decoding process, pre-processing of the required SCA parameters will occur and the results stored in the past-history buffer. If a speech frame is detected to be lost or in error, then extrapolation modules are executed and replacement SCA parameters are generated and sent as the parameters required by the SCA. In this way, the information transfer to the SCA is transparent, and the SCA processing continues as usual. The listener will not normally notice that a speech frame has been lost because of the smooth transition between the last-received, lost, and next-received speech frames.

27 CFR 447.62 - False statements or concealment of facts.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true False statements or concealment of facts. 447.62 Section 447.62 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.62 - False statements or concealment of facts.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false False statements or concealment of facts. 447.62 Section 447.62 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.62 - False statements or concealment of facts.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true False statements or concealment of facts. 447.62 Section 447.62 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.62 - False statements or concealment of facts.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false False statements or concealment of facts. 447.62 Section 447.62 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.62 - False statements or concealment of facts.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false False statements or concealment of facts. 447.62 Section 447.62 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

Information Management Strategies in Early Adolescence: Developmental Change in Use and Transactional Associations with Psychological Adjustment

ERIC Educational Resources Information Center

Laird, Robert D.; Marrero, Matthew D.; Melching, Jessica A.; Kuhn, Emily S.

2013-01-01

Adolescents use various strategies to manage their parents' access to information. This study tested developmental change in strategy use, longitudinal associations between disclosing and concealing strategies, and longitudinal associations linking disclosing and concealing strategies with antisocial behavior and depressive symptoms. Self-report…

Automated Human Screening for Detecting Concealed Knowledge

ERIC Educational Resources Information Center

Twyman, Nathan W.

2012-01-01

Screening individuals for concealed knowledge has traditionally been the purview of professional interrogators investigating a crime. But the ability to detect when a person is hiding important information would be of high value to many other fields and functions. This dissertation proposes design principles for and reports on an implementation…

The Effects of Concealing Academic Achievement Information on Adolescents' Self-Concept

ERIC Educational Resources Information Center

Zhang, Baoshan; Wang, Mo; Li, Juan; Yu, Guoliang; Bi, Yan-Ling

2011-01-01

Using an experimental design, the effect of concealing academic achievement information on adolescents' self-concept was examined in the current study. Specifically, adolescents with low academic achievement and adolescents with average to high academic achievement (N = 129) were randomly assigned to different interview contexts wherein…

Concealed Questions. In Search of Answers

ERIC Educational Resources Information Center

Frana, Ilaria

2010-01-01

This dissertation examines the semantic interpretation of various types of DPs in so-called concealed-question (CQ) constructions, as "Bill's phone number" in the sentence "John knows Bill's phone number". The peculiar characteristic of DP-CQs is that they are interpreted as having the meaning of an embedded question. So, for instance, the…

Hard x-ray focusing optics for concealed object detection

NASA Astrophysics Data System (ADS)

Jannson, Tomasz; Gertsenshteyn, Michael

2006-05-01

In this paper, we discuss hard x-ray optics, in general, and lobster-eye focusing optics, in particular, for concealed object detection, at longer distances. The longer distance (~50m) scenario is important for Improvised Explosives Detection (IED), "seeing through walls," "seeing objects under ground," and related applications.

Ground roost resource selection for Merriam's wild turkeys

Treesearch

Chad P. Lehman; Daniel J. Thompson; Mark A. Rumble

2010-01-01

Concealment cover is important for ground-roosting wild turkey (Meleagris gallopavo) poults immediately following hatch during the vulnerable, preflight stage. We compared concealment cover resources selected at ground roosts to those of nest sites and available resources for Merriam's turkeys (Meleagris gallopavo merriami) in the Black Hills of South Dakota, USA...

EMC: Air Quality Forecast Home page

Science.gov Websites

archive NAM Verification Meteorology Error Time Series EMC NAM Spatial Maps Real Time Mesoscale Analysis Precipitation verification NAQFC VERIFICATION CMAQ Ozone & PM Error Time Series AOD Error Time Series HYSPLIT Smoke forecasts vs GASP satellite Dust and Smoke Error Time Series HYSPLIT WCOSS Upgrade (July

Neuropsychology of selective attention and magnetic cortical stimulation.

PubMed

Sabatino, M; Di Nuovo, S; Sardo, P; Abbate, C S; La Grutta, V

1996-01-01

Informed volunteers were asked to perform different neuropsychological tests involving selective attention under control conditions and during transcranial magnetic cortical stimulation. The tests chosen involved the recognition of a specific letter among different letters (verbal test) and the search for three different spatial orientations of an appendage to a square (visuo-spatial test). For each test the total time taken and the error rate were calculated. Results showed that cortical stimulation did not cause a worsening in performance. Moreover, magnetic stimulation of the temporal lobe neither modified completion time in both verbal and visuo-spatial tests nor changed error rate. In contrast, magnetic stimulation of the pre-frontal area induced a significant reduction in the performance time of both the verbal and visuo-spatial tests always without an increase in the number of errors. The experimental findings underline the importance of the pre-frontal area in performing tasks requiring a high level of controlled attention and suggest the need to adopt an interdisciplinary approach towards the study of neurone/mind interface mechanisms.

Evaluation of spatial filtering on the accuracy of wheat area estimate

NASA Technical Reports Server (NTRS)

Dejesusparada, N. (Principal Investigator); Moreira, M. A.; Chen, S. C.; Delima, A. M.

1982-01-01

A 3 x 3 pixel spatial filter for postclassification was used for wheat classification to evaluate the effects of this procedure on the accuracy of area estimation using LANDSAT digital data obtained from a single pass. Quantitative analyses were carried out in five test sites (approx 40 sq km each) and t tests showed that filtering with threshold values significantly decreased errors of commission and omission. In area estimation filtering improved the overestimate of 4.5% to 2.7% and the root-mean-square error decreased from 126.18 ha to 107.02 ha. Extrapolating the same procedure of automatic classification using spatial filtering for postclassification to the whole study area, the accuracy in area estimate was improved from the overestimate of 10.9% to 9.7%. It is concluded that when single pass LANDSAT data is used for crop identification and area estimation the postclassification procedure using a spatial filter provides a more accurate area estimate by reducing classification errors.

Hiding in plain sight: use of realistic surrogates to reduce exposure of protected health information in clinical text.

PubMed

Carrell, David; Malin, Bradley; Aberdeen, John; Bayer, Samuel; Clark, Cheryl; Wellner, Ben; Hirschman, Lynette

2013-01-01

Secondary use of clinical text is impeded by a lack of highly effective, low-cost de-identification methods. Both, manual and automated methods for removing protected health information, are known to leave behind residual identifiers. The authors propose a novel approach for addressing the residual identifier problem based on the theory of Hiding In Plain Sight (HIPS). HIPS relies on obfuscation to conceal residual identifiers. According to this theory, replacing the detected identifiers with realistic but synthetic surrogates should collectively render the few 'leaked' identifiers difficult to distinguish from the synthetic surrogates. The authors conducted a pilot study to test this theory on clinical narrative, de-identified by an automated system. Test corpora included 31 oncology and 50 family practice progress notes read by two trained chart abstractors and an informaticist. Experimental results suggest approximately 90% of residual identifiers can be effectively concealed by the HIPS approach in text containing average and high densities of personal identifying information. This pilot test suggests HIPS is feasible, but requires further evaluation. The results need to be replicated on larger corpora of diverse origin under a range of detection scenarios. Error analyses also suggest areas where surrogate generation techniques can be refined to improve efficacy. If these results generalize to existing high-performing de-identification systems with recall rates of 94-98%, HIPS could increase the effective de-identification rates of these systems to levels above 99% without further advancements in system recall. Additional and more rigorous assessment of the HIPS approach is warranted.

Void Growth and Coalescence Simulations

DTIC Science & Technology

2013-08-01

distortion and damage, minimum time step, and appropriate material model parameters. Further, a temporal and spatial convergence study was used to...estimate errors, thus, this study helps to provide guidelines for modeling of materials with voids. Finally, we use a Gurson model with Johnson-Cook...spatial convergence study was used to estimate errors, thus, this study helps to provide guidelines for modeling of materials with voids. Finally, we

BaTMAn: Bayesian Technique for Multi-image Analysis

NASA Astrophysics Data System (ADS)

Casado, J.; Ascasibar, Y.; García-Benito, R.; Guidi, G.; Choudhury, O. S.; Bellocchi, E.; Sánchez, S. F.; Díaz, A. I.

2016-12-01

Bayesian Technique for Multi-image Analysis (BaTMAn) characterizes any astronomical dataset containing spatial information and performs a tessellation based on the measurements and errors provided as input. The algorithm iteratively merges spatial elements as long as they are statistically consistent with carrying the same information (i.e. identical signal within the errors). The output segmentations successfully adapt to the underlying spatial structure, regardless of its morphology and/or the statistical properties of the noise. BaTMAn identifies (and keeps) all the statistically-significant information contained in the input multi-image (e.g. an IFS datacube). The main aim of the algorithm is to characterize spatially-resolved data prior to their analysis.

Identifying the location of a concealed object through unintentional eye movements

PubMed Central

Neuman, Yair; Assaf, Dan; Israeli, Navot

2015-01-01

In some investigative and interrogative contexts, the investigator is seeking to identify the location of an object (e.g., implanted bomb) which is known to a given subject (e.g., a terrorist). In this paper, we present a non-intrusive methodology for uncovering the loci of a concealed object by analyzing the subject's eye movements. Using a combination of eye tracking, psychological manipulation and a search algorithm, we have performed two experiments. In the first experiment, we have gained 58% hit rate in identifying the location of the concealed object and in the second experiment 56% hit rate. The pros and cons of the methodology for forensic investigation are discussed. PMID:25904879

The relationship between perfectionism and engagement in preventive health behaviours: the mediating role of self-concealment.

PubMed

Williams, Charlotte J; Cropley, Mark

2014-10-01

If perfectionists avoid engaging in preventive health behaviours, they may be putting their long-term health and well-being at risk. Correlational analyses based on a sample of 370 university students identified maladaptive perfectionism to be associated with decreased levels of engagement in preventive health behaviours, life satisfaction and well-being and increased levels of self-concealment and psychological distress. Adaptive perfectionism was associated with higher levels of engagement in preventive health behaviours. Self-concealment was identified as a partial mediator in the relationship between maladaptive perfectionism and both engagement in preventive health behaviours and psychological distress. Implications of the findings are discussed. © The Author(s) 2013.

Being and feeling unique: statistical deviance and psychological marginality.

PubMed

Frable, D E

1993-03-01

Two studies tested the hypothesis that people with culturally stigmatized and concealable conditions (e.g., gays, epileptics, juvenile delinquents, and incest victims) would be more likely to feel unique than people with culturally valued or conspicuous conditions (e.g., the physically attractive, the intellectually gifted, the obese, and the facially scarred). In Study 1, culturally stigmatized individuals with concealable conditions were least likely to perceive consensus between their personal preferences and those of others. In Study 2, they were most likely to describe themselves as unique and to make these self-relevant decisions quickly. Marginality is a psychological reality, not just a statistical one, for those with stigmatized and concealable "master status" conditions.

Simulation of wave propagation in three-dimensional random media

NASA Technical Reports Server (NTRS)

Coles, William A.; Filice, J. P.; Frehlich, R. G.; Yadlowsky, M.

1993-01-01

Quantitative error analysis for simulation of wave propagation in three dimensional random media assuming narrow angular scattering are presented for the plane wave and spherical wave geometry. This includes the errors resulting from finite grid size, finite simulation dimensions, and the separation of the two-dimensional screens along the propagation direction. Simple error scalings are determined for power-law spectra of the random refractive index of the media. The effects of a finite inner scale are also considered. The spatial spectra of the intensity errors are calculated and compared to the spatial spectra of intensity. The numerical requirements for a simulation of given accuracy are determined for realizations of the field. The numerical requirements for accurate estimation of higher moments of the field are less stringent.

Haptic spatial matching in near peripersonal space.

PubMed

Kaas, Amanda L; Mier, Hanneke I van

2006-04-01

Research has shown that haptic spatial matching at intermanual distances over 60 cm is prone to large systematic errors. The error pattern has been explained by the use of reference frames intermediate between egocentric and allocentric coding. This study investigated haptic performance in near peripersonal space, i.e. at intermanual distances of 60 cm and less. Twelve blindfolded participants (six males and six females) were presented with two turn bars at equal distances from the midsagittal plane, 30 or 60 cm apart. Different orientations (vertical/horizontal or oblique) of the left bar had to be matched by adjusting the right bar to either a mirror symmetric (/ \\) or parallel (/ /) position. The mirror symmetry task can in principle be performed accurately in both an egocentric and an allocentric reference frame, whereas the parallel task requires an allocentric representation. Results showed that parallel matching induced large systematic errors which increased with distance. Overall error was significantly smaller in the mirror task. The task difference also held for the vertical orientation at 60 cm distance, even though this orientation required the same response in both tasks, showing a marked effect of task instruction. In addition, men outperformed women on the parallel task. Finally, contrary to our expectations, systematic errors were found in the mirror task, predominantly at 30 cm distance. Based on these findings, we suggest that haptic performance in near peripersonal space might be dominated by different mechanisms than those which come into play at distances over 60 cm. Moreover, our results indicate that both inter-individual differences and task demands affect task performance in haptic spatial matching. Therefore, we conclude that the study of haptic spatial matching in near peripersonal space might reveal important additional constraints for the specification of adequate models of haptic spatial performance.

Measurement Error Correction for Predicted Spatiotemporal Air Pollution Exposures.

PubMed

Keller, Joshua P; Chang, Howard H; Strickland, Matthew J; Szpiro, Adam A

2017-05-01

Air pollution cohort studies are frequently analyzed in two stages, first modeling exposure then using predicted exposures to estimate health effects in a second regression model. The difference between predicted and unobserved true exposures introduces a form of measurement error in the second stage health model. Recent methods for spatial data correct for measurement error with a bootstrap and by requiring the study design ensure spatial compatibility, that is, monitor and subject locations are drawn from the same spatial distribution. These methods have not previously been applied to spatiotemporal exposure data. We analyzed the association between fine particulate matter (PM2.5) and birth weight in the US state of Georgia using records with estimated date of conception during 2002-2005 (n = 403,881). We predicted trimester-specific PM2.5 exposure using a complex spatiotemporal exposure model. To improve spatial compatibility, we restricted to mothers residing in counties with a PM2.5 monitor (n = 180,440). We accounted for additional measurement error via a nonparametric bootstrap. Third trimester PM2.5 exposure was associated with lower birth weight in the uncorrected (-2.4 g per 1 μg/m difference in exposure; 95% confidence interval [CI]: -3.9, -0.8) and bootstrap-corrected (-2.5 g, 95% CI: -4.2, -0.8) analyses. Results for the unrestricted analysis were attenuated (-0.66 g, 95% CI: -1.7, 0.35). This study presents a novel application of measurement error correction for spatiotemporal air pollution exposures. Our results demonstrate the importance of spatial compatibility between monitor and subject locations and provide evidence of the association between air pollution exposure and birth weight.

The effects of spatial autoregressive dependencies on inference in ordinary least squares: a geometric approach

NASA Astrophysics Data System (ADS)

Smith, Tony E.; Lee, Ka Lok

2012-01-01

There is a common belief that the presence of residual spatial autocorrelation in ordinary least squares (OLS) regression leads to inflated significance levels in beta coefficients and, in particular, inflated levels relative to the more efficient spatial error model (SEM). However, our simulations show that this is not always the case. Hence, the purpose of this paper is to examine this question from a geometric viewpoint. The key idea is to characterize the OLS test statistic in terms of angle cosines and examine the geometric implications of this characterization. Our first result is to show that if the explanatory variables in the regression exhibit no spatial autocorrelation, then the distribution of test statistics for individual beta coefficients in OLS is independent of any spatial autocorrelation in the error term. Hence, inferences about betas exhibit all the optimality properties of the classic uncorrelated error case. However, a second more important series of results show that if spatial autocorrelation is present in both the dependent and explanatory variables, then the conventional wisdom is correct. In particular, even when an explanatory variable is statistically independent of the dependent variable, such joint spatial dependencies tend to produce "spurious correlation" that results in over-rejection of the null hypothesis. The underlying geometric nature of this problem is clarified by illustrative examples. The paper concludes with a brief discussion of some possible remedies for this problem.

Evaluation of the predicted error of the soil moisture retrieval from C-band SAR by comparison against modelled soil moisture estimates over Australia

PubMed Central

Doubková, Marcela; Van Dijk, Albert I.J.M.; Sabel, Daniel; Wagner, Wolfgang; Blöschl, Günter

2012-01-01

The Sentinel-1 will carry onboard a C-band radar instrument that will map the European continent once every four days and the global land surface at least once every twelve days with finest 5 × 20 m spatial resolution. The high temporal sampling rate and operational configuration make Sentinel-1 of interest for operational soil moisture monitoring. Currently, updated soil moisture data are made available at 1 km spatial resolution as a demonstration service using Global Mode (GM) measurements from the Advanced Synthetic Aperture Radar (ASAR) onboard ENVISAT. The service demonstrates the potential of the C-band observations to monitor variations in soil moisture. Importantly, a retrieval error estimate is also available; these are needed to assimilate observations into models. The retrieval error is estimated by propagating sensor errors through the retrieval model. In this work, the existing ASAR GM retrieval error product is evaluated using independent top soil moisture estimates produced by the grid-based landscape hydrological model (AWRA-L) developed within the Australian Water Resources Assessment system (AWRA). The ASAR GM retrieval error estimate, an assumed prior AWRA-L error estimate and the variance in the respective datasets were used to spatially predict the root mean square error (RMSE) and the Pearson's correlation coefficient R between the two datasets. These were compared with the RMSE calculated directly from the two datasets. The predicted and computed RMSE showed a very high level of agreement in spatial patterns as well as good quantitative agreement; the RMSE was predicted within accuracy of 4% of saturated soil moisture over 89% of the Australian land mass. Predicted and calculated R maps corresponded within accuracy of 10% over 61% of the continent. The strong correspondence between the predicted and calculated RMSE and R builds confidence in the retrieval error model and derived ASAR GM error estimates. The ASAR GM and Sentinel-1 have the same basic physical measurement characteristics, and therefore very similar retrieval error estimation method can be applied. Because of the expected improvements in radiometric resolution of the Sentinel-1 backscatter measurements, soil moisture estimation errors can be expected to be an order of magnitude less than those for ASAR GM. This opens the possibility for operationally available medium resolution soil moisture estimates with very well-specified errors that can be assimilated into hydrological or crop yield models, with potentially large benefits for land-atmosphere fluxes, crop growth, and water balance monitoring and modelling. PMID:23483015

Do Children Understand That People Selectively Conceal or Express Emotion?

ERIC Educational Resources Information Center

Hayashi, Hajimu; Shiomi, Yuki

2015-01-01

This study examined whether children understand that people selectively conceal or express emotion depending upon the context. We prepared two contexts for a verbal display task for 70 first-graders, 80 third-graders, 64 fifth-graders, and 71 adults. In both contexts, protagonists had negative feelings because of the behavior of the other…

The Psychological Implications of Concealing a Stigma: A Cognitive-Affective-Behavioral Model

ERIC Educational Resources Information Center

Pachankis, John E.

2007-01-01

Many assume that individuals with a hidden stigma escape the difficulties faced by individuals with a visible stigma. However, recent research has shown that individuals with a concealable stigma also face considerable stressors and psychological challenges. The ambiguity of social situations combined with the threat of potential discovery makes…

The Cost of Question Concealment: Eye-Tracking and MEG Evidence

ERIC Educational Resources Information Center

Harris, Jesse; Pylkkanen, Liina; McElree, Brian; Frisson, Steven

2008-01-01

Although natural language appears to be largely compositional, the meanings of certain expressions cannot be straightforwardly recovered from the meanings of their parts. This study examined the online processing of one such class of expressions: "concealed questions", in which the meaning of a complex noun phrase ("the proof of the theorem")…

Turkey habitat use and nesting characteristics in ponderosa pine

Treesearch

Mark A. Rumble; Stanley H. Anderson

1987-01-01

Turkeys (Meleagris gallapovo) selected nest sites that provided good horizontal concealment. Rock or rock outcrops were selected most frequently for nest concealment on first-nest attempts. Renest attempts showed a selection preference for shrubs as nest cover; most of these were located in meadows. Nesting success doubled for renests versus first...

Gender-specific health implications of minority stress among lesbians and gay men.

PubMed

Bariola, Emily; Lyons, Anthony; Leonard, William

2016-12-01

Lesbians and gay men are exposed to unique minority stressors. We examined the health implications of one type of distal minority stressor (victimisation) and one type of proximal minority stressor (sexual identity concealment due to anticipated stigma) among lesbians and gay men. Gender-specific health implications were assessed. Data were collected via an online survey involving an Australian sample of 1,470 gay men and 1,264 lesbians. Survey questions assessed demographics, experiences of different forms of sexual identity-related victimisation and sexual identity concealment in a variety of contexts. Health outcomes included self-reported general health, illicit drug use, frequency of alcohol consumption, smoking status, and weight status. Gay men reported higher rates of victimisation and identity concealment than lesbians. Controlling for demographic differences, experiences of victimisation were associated with poorer self-rated health, illicit drug use, and smoking among both gay men and lesbians. In contrast, identity concealment was linked with poorer health outcomes among lesbians only. Our findings offer new insights into the potential antecedents of the health inequalities that have previously been reported for these populations. © 2016 Public Health Association of Australia.

Image fusion based on millimeter-wave for concealed weapon detection

NASA Astrophysics Data System (ADS)

Zhu, Weiwen; Zhao, Yuejin; Deng, Chao; Zhang, Cunlin; Zhang, Yalin; Zhang, Jingshui

2010-11-01

This paper describes a novel multi sensors image fusion technology which is presented for concealed weapon detection (CWD). It is known to all, because of the good transparency of the clothes at millimeter wave band, a millimeter wave radiometer can be used to image and distinguish concealed contraband beneath clothes, for example guns, knives, detonator and so on. As a result, we adopt the passive millimeter wave (PMMW) imaging technology for airport security. However, in consideration of the wavelength of millimeter wave and the single channel mechanical scanning, the millimeter wave image has law optical resolution, which can't meet the need of practical application. Therefore, visible image (VI), which has higher resolution, is proposed for the image fusion with the millimeter wave image to enhance the readability. Before the image fusion, a novel image pre-processing which specifics to the fusion of millimeter wave imaging and visible image is adopted. And in the process of image fusion, multi resolution analysis (MRA) based on Wavelet Transform (WT) is adopted. In this way, the experiment result shows that this method has advantages in concealed weapon detection and has practical significance.

Assessing uncertainty in SRTM elevations for global flood modelling

NASA Astrophysics Data System (ADS)

Hawker, L. P.; Rougier, J.; Neal, J. C.; Bates, P. D.

2017-12-01

The SRTM DEM is widely used as the topography input to flood models in data-sparse locations. Understanding spatial error in the SRTM product is crucial in constraining uncertainty about elevations and assessing the impact of these upon flood prediction. Assessment of SRTM error was carried out by Rodriguez et al (2006), but this did not explicitly quantify the spatial structure of vertical errors in the DEM, and nor did it distinguish between errors over different types of landscape. As a result, there is a lack of information about spatial structure of vertical errors of the SRTM in the landscape that matters most to flood models - the floodplain. Therefore, this study attempts this task by comparing SRTM, an error corrected SRTM product (The MERIT DEM of Yamazaki et al., 2017) and near truth LIDAR elevations for 3 deltaic floodplains (Mississippi, Po, Wax Lake) and a large lowland region (the Fens, UK). Using the error covariance function, calculated by comparing SRTM elevations to the near truth LIDAR, perturbations of the 90m SRTM DEM were generated, producing a catalogue of plausible DEMs. This allows modellers to simulate a suite of plausible DEMs at any aggregated block size above native SRTM resolution. Finally, the generated DEM's were input into a hydrodynamic model of the Mekong Delta, built using the LISFLOOD-FP hydrodynamic model, to assess how DEM error affects the hydrodynamics and inundation extent across the domain. The end product of this is an inundation map with the probability of each pixel being flooded based on the catalogue of DEMs. In a world of increasing computer power, but a lack of detailed datasets, this powerful approach can be used throughout natural hazard modelling to understand how errors in the SRTM DEM can impact the hazard assessment.

Dual Systems for Spatial Updating in Immediate and Retrieved Environments: Evidence from Bias Analysis.

PubMed

Liu, Chuanjun; Xiao, Chengli

2018-01-01

The spatial updating and memory systems are employed during updating in both the immediate and retrieved environments. However, these dual systems seem to work differently, as the difference of pointing latency and absolute error between the two systems vary across environments. To verify this issue, the present study employed the bias analysis of signed errors based on the hypothesis that the transformed representation will bias toward the original one. Participants learned a spatial layout and then either stayed in the learning location or were transferred to a neighboring room directly or after being disoriented. After that, they performed spatial judgments from perspectives aligned with the learning direction, aligned with the direction they faced during the test, or a novel direction misaligned with the two above-mentioned directions. The patterns of signed error bias were consistent across environments. Responses for memory aligned perspectives were unbiased, whereas responses for sensorimotor aligned perspectives were biased away from the memory aligned perspective, and responses for misaligned perspectives were biased toward sensorimotor aligned perspectives. These findings indicate that the spatial updating system is consistently independent of the spatial memory system regardless of the environments, but the updating system becomes less accessible as the environment changes from immediate to a retrieved one.

Dual Systems for Spatial Updating in Immediate and Retrieved Environments: Evidence from Bias Analysis

PubMed Central

Liu, Chuanjun; Xiao, Chengli

2018-01-01

The spatial updating and memory systems are employed during updating in both the immediate and retrieved environments. However, these dual systems seem to work differently, as the difference of pointing latency and absolute error between the two systems vary across environments. To verify this issue, the present study employed the bias analysis of signed errors based on the hypothesis that the transformed representation will bias toward the original one. Participants learned a spatial layout and then either stayed in the learning location or were transferred to a neighboring room directly or after being disoriented. After that, they performed spatial judgments from perspectives aligned with the learning direction, aligned with the direction they faced during the test, or a novel direction misaligned with the two above-mentioned directions. The patterns of signed error bias were consistent across environments. Responses for memory aligned perspectives were unbiased, whereas responses for sensorimotor aligned perspectives were biased away from the memory aligned perspective, and responses for misaligned perspectives were biased toward sensorimotor aligned perspectives. These findings indicate that the spatial updating system is consistently independent of the spatial memory system regardless of the environments, but the updating system becomes less accessible as the environment changes from immediate to a retrieved one. PMID:29467698

Underestimating the effects of spatial heterogeneity due to individual movement and spatial scale: infectious disease as an example

USGS Publications Warehouse

Cross, Paul C.; Caillaud, Damien; Heisey, Dennis M.

2013-01-01

Many ecological and epidemiological studies occur in systems with mobile individuals and heterogeneous landscapes. Using a simulation model, we show that the accuracy of inferring an underlying biological process from observational data depends on movement and spatial scale of the analysis. As an example, we focused on estimating the relationship between host density and pathogen transmission. Observational data can result in highly biased inference about the underlying process when individuals move among sampling areas. Even without sampling error, the effect of host density on disease transmission is underestimated by approximately 50 % when one in ten hosts move among sampling areas per lifetime. Aggregating data across larger regions causes minimal bias when host movement is low, and results in less biased inference when movement rates are high. However, increasing data aggregation reduces the observed spatial variation, which would lead to the misperception that a spatially targeted control effort may not be very effective. In addition, averaging over the local heterogeneity will result in underestimating the importance of spatial covariates. Minimizing the bias due to movement is not just about choosing the best spatial scale for analysis, but also about reducing the error associated with using the sampling location as a proxy for an individual’s spatial history. This error associated with the exposure covariate can be reduced by choosing sampling regions with less movement, including longitudinal information of individuals’ movements, or reducing the window of exposure by using repeated sampling or younger individuals.

Patient identification using a near-infrared laser scanner

NASA Astrophysics Data System (ADS)

Manit, Jirapong; Bremer, Christina; Schweikard, Achim; Ernst, Floris

2017-03-01

We propose a new biometric approach where the tissue thickness of a person's forehead is used as a biometric feature. Given that the spatial registration of two 3D laser scans of the same human face usually produces a low error value, the principle of point cloud registration and its error metric can be applied to human classification techniques. However, by only considering the spatial error, it is not possible to reliably verify a person's identity. We propose to use a novel near-infrared laser-based head tracking system to determine an additional feature, the tissue thickness, and include this in the error metric. Using MRI as a ground truth, data from the foreheads of 30 subjects was collected from which a 4D reference point cloud was created for each subject. The measurements from the near-infrared system were registered with all reference point clouds using the ICP algorithm. Afterwards, the spatial and tissue thickness errors were extracted, forming a 2D feature space. For all subjects, the lowest feature distance resulted from the registration of a measurement and the reference point cloud of the same person. The combined registration error features yielded two clusters in the feature space, one from the same subject and another from the other subjects. When only the tissue thickness error was considered, these clusters were less distinct but still present. These findings could help to raise safety standards for head and neck cancer patients and lays the foundation for a future human identification technique.

Effects of modified penoplasty for concealed penis in children.

PubMed

Chen, Chao; Li, Ning; Luo, Yi-Ge; Wang, Hong; Tang, Xian-Ming; Chen, Jia-Bo; Dong, Chun-Qiang; Liu, Qiang; Dong, Kun; Su, Cheng; Yang, Ti-Quan

2016-10-01

To evaluate the effect of modified penoplasty in the management of concealed penis. We retrospectively reviewed 96 consecutive patients with concealed penis, which had been surgically corrected between July 2013 and July 2015. All patients underwent modified Shiraki phalloplasty. All patients were scheduled for regular follow-up at 1, 3, and 6 months after the surgery. Data on the patients' age, operative time, postoperative complications, and parents' satisfaction grade were collected and analyzed. The mean follow-up period was 17.4 months (range 7-31 months). The mean operative time was 63.2 ± 8.7 min. The mean perpendicular penile length was 1.89 ± 0.77 cm preoperatively and 4.42 ± 0.87 cm postoperatively, with an improved mean length of 2.5 ± 0.68 cm in the flaccid state postoperatively (p < 0.05). The patients' satisfaction grades after the surgery were improved significantly (p < 0.05). Fifty-two patients had penile lymphedema postoperatively; however, it disappeared spontaneously within 3 months. Additionally, postoperative wound infection occurred in two patients. There were no complications such as flap necrosis, penile shaft contracture, voiding difficulty, and erection difficulties. The modified Shiraki phalloplasty for concealed penis can achieve maximum utilization of prepuce to assure coverage of the exposed penile shaft. It has fewer complications, achieving marked asthetics, and functional improvement. It is a relatively ideal means for treating concealed penis.

Switching between Spatial Stimulus-Response Mappings: A Developmental Study of Cognitive Flexibility

ERIC Educational Resources Information Center

Crone, Eveline A.; Ridderinkhof, K. Richard; Worm, Mijkje; Somsen, Riek J. M.; van der Molen, Maurits W.

2004-01-01

Four different age groups (8-9-year-olds, 11-12-year-olds, 13-15-year-olds and young adults) performed a spatial rule-switch task in which the sorting rule had to be detected on the basis of feedback or on the basis of switch cues. Performance errors were examined on the basis of a recently introduced method of error scoring for the Wisconsin Card…

Prevention of firearm-related injuries with restrictive licensing and concealed carry laws: An Eastern Association for the Surgery of Trauma systematic review.

PubMed

Crandall, Marie; Eastman, Alexander; Violano, Pina; Greene, Wendy; Allen, Steven; Block, Ernest; Christmas, Ashley Britton; Dennis, Andrew; Duncan, Thomas; Foster, Shannon; Goldberg, Stephanie; Hirsh, Michael; Joseph, D'Andrea; Lommel, Karen; Pappas, Peter; Shillinglaw, William

2016-11-01

In the past decade, more than 300,000 people in the United States have died from firearm injuries. Our goal was to assess the effectiveness of two particular prevention strategies, restrictive licensing of firearms and concealed carry laws, on firearm-related injuries in the US Restrictive Licensing was defined to include denials of ownership for various offenses, such as performing background checks for domestic violence and felony convictions. Concealed carry laws allow licensed individuals to carry concealed weapons. A comprehensive review of the literature was performed. We used Grading of Recommendations Assessment, Development, and Evaluation methodology to assess the breadth and quality of the data specific to our Population, Intervention, Comparator, Outcomes (PICO) questions. A total of 4673 studies were initially identified, then seven more added after two subsequent, additional literature reviews. Of these, 3,623 remained after removing duplicates; 225 case reports, case series, and reviews were excluded, and 3,379 studies were removed because they did not focus on prevention or did not address our comparators of interest. This left a total of 14 studies which merited inclusion for PICO 1 and 13 studies which merited inclusion for PICO 2. PICO 1: We recommend the use of restrictive licensing to reduce firearm-related injuries.PICO 2: We recommend against the use of concealed carry laws to reduce firearm-related injuries.This committee found an association between more restrictive licensing and lower firearm injury rates. All 14 studies were population-based, longitudinal, used modeling to control for covariates, and 11 of the 14 were multi-state. Twelve of the studies reported reductions in firearm injuries, from 7% to 40%. We found no consistent effect of concealed carry laws. Of note, the varied quality of the available data demonstrates a significant information gap, and this committee recommends that we as a society foster a nurturing and encouraging environment that can strengthen future evidence based guidelines. Systematic review, level III.

Sensitivity and Specificity of Emergency Physicians and Trainees for Identifying Internally Concealed Drug Packages on Abdominal Computed Tomography Scan: Do Lung Windows Improve Accuracy?

PubMed

Asha, Stephen Edward; Cooke, Andrew

2015-09-01

Suspected body packers may be brought to emergency departments (EDs) close to international airports for abdominal computed tomography (CT) scanning. Senior emergency clinicians may be asked to interpret these CT scans. Missing concealed drug packages have important clinical and forensic implications. The accuracy of emergency clinician interpretation of abdominal CT scans for concealed drugs is not known. Limited evidence suggests that accuracy for identification of concealed packages can be increased by viewing CT images on "lung window" settings. To determine the accuracy of senior emergency clinicians in interpreting abdominal CT scans for concealed drugs, and to determine if this accuracy was improved by viewing scans on both abdominal and lung window settings. Emergency clinicians blinded to all patient identifiers and the radiology report interpreted CT scans of suspected body packers using standard abdominal window settings and then with the addition of lung window settings. The reference standard was the radiologist's report. Fifty-five emergency clinicians reported 235 CT scans. The sensitivity, specificity, and accuracy of interpretation using abdominal windows was 89.9% (95% confidence interval [CI] 83.0-94.7), 81.9% (95% CI 73.7-88.4), and 86.0% (95% CI 81.5-90.4), respectively, and with both window settings was 94.1% (95% CI 88.3-97.6), 76.7% (95% CI 68.0-84.1), 85.5% (95% CI 81.0-90.0), respectively. Diagnostic accuracy was similar regardless of the clinician's experience. Interrater reliability was moderate (kappa 0.46). The accuracy of interpretation of abdominal CT scans performed for the purpose of detecting concealed drug packages by emergency clinicians is not high enough to safely discharge these patients from the ED. The use of lung windows improved sensitivity, but at the expense of specificity. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Precise method of compensating radiation-induced errors in a hot-cathode-ionization gauge with correcting electrode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saeki, Hiroshi, E-mail: saeki@spring8.or.jp; Magome, Tamotsu, E-mail: saeki@spring8.or.jp

2014-10-06

To compensate pressure-measurement errors caused by a synchrotron radiation environment, a precise method using a hot-cathode-ionization-gauge head with correcting electrode, was developed and tested in a simulation experiment with excess electrons in the SPring-8 storage ring. This precise method to improve the measurement accuracy, can correctly reduce the pressure-measurement errors caused by electrons originating from the external environment, and originating from the primary gauge filament influenced by spatial conditions of the installed vacuum-gauge head. As the result of the simulation experiment to confirm the performance reducing the errors caused by the external environment, the pressure-measurement error using this method wasmore » approximately less than several percent in the pressure range from 10{sup −5} Pa to 10{sup −8} Pa. After the experiment, to confirm the performance reducing the error caused by spatial conditions, an additional experiment was carried out using a sleeve and showed that the improved function was available.« less

Mathematics skills in good readers with hydrocephalus.

PubMed

Barnes, Marcia A; Pengelly, Sarah; Dennis, Maureen; Wilkinson, Margaret; Rogers, Tracey; Faulkner, Heather

2002-01-01

Children with hydrocephalus have poor math skills. We investigated the nature of their arithmetic computation errors by comparing written subtraction errors in good readers with hydrocephalus, typically developing good readers of the same age, and younger children matched for math level to the children with hydrocephalus. Children with hydrocephalus made more procedural errors (although not more fact retrieval or visual-spatial errors) than age-matched controls; they made the same number of procedural errors as younger, math-level matched children. We also investigated a broad range of math abilities, and found that children with hydrocephalus performed more poorly than age-matched controls on tests of geometry and applied math skills such as estimation and problem solving. Computation deficits in children with hydrocephalus reflect delayed development of procedural knowledge. Problems in specific math domains such as geometry and applied math, were associated with deficits in constituent cognitive skills such as visual spatial competence, memory, and general knowledge.

Adaptive optics system performance approximations for atmospheric turbulence correction

NASA Astrophysics Data System (ADS)

Tyson, Robert K.

1990-10-01

Analysis of adaptive optics system behavior often can be reduced to a few approximations and scaling laws. For atmospheric turbulence correction, the deformable mirror (DM) fitting error is most often used to determine a priori the interactuator spacing and the total number of correction zones required. This paper examines the mirror fitting error in terms of its most commonly used exponential form. The explicit constant in the error term is dependent on deformable mirror influence function shape and actuator geometry. The method of least squares fitting of discrete influence functions to the turbulent wavefront is compared to the linear spatial filtering approximation of system performance. It is found that the spatial filtering method overstimates the correctability of the adaptive optics system by a small amount. By evaluating fitting error for a number of DM configurations, actuator geometries, and influence functions, fitting error constants verify some earlier investigations.

Performance evaluation of spatial compounding in the presence of aberration and adaptive imaging

NASA Astrophysics Data System (ADS)

Dahl, Jeremy J.; Guenther, Drake; Trahey, Gregg E.

2003-05-01

Spatial compounding has been used for years to reduce speckle in ultrasonic images and to resolve anatomical features hidden behind the grainy appearance of speckle. Adaptive imaging restores image contrast and resolution by compensating for beamforming errors caused by tissue-induced phase errors. Spatial compounding represents a form of incoherent imaging, whereas adaptive imaging attempts to maintain a coherent, diffraction-limited aperture in the presence of aberration. Using a Siemens Antares scanner, we acquired single channel RF data on a commercially available 1-D probe. Individual channel RF data was acquired on a cyst phantom in the presence of a near field electronic phase screen. Simulated data was also acquired for both a 1-D and a custom built 8x96, 1.75-D probe (Tetrad Corp.). The data was compounded using a receive spatial compounding algorithm; a widely used algorithm because it takes advantage of parallel beamforming to avoid reductions in frame rate. Phase correction was also performed by using a least mean squares algorithm to estimate the arrival time errors. We present simulation and experimental data comparing the performance of spatial compounding to phase correction in contrast and resolution tasks. We evaluate spatial compounding and phase correction, and combinations of the two methods, under varying aperture sizes, aperture overlaps, and aberrator strength to examine the optimum configuration and conditions in which spatial compounding will provide a similar or better result than adaptive imaging. We find that, in general, phase correction is hindered at high aberration strengths and spatial frequencies, whereas spatial compounding is helped by these aberrators.

A priori discretization error metrics for distributed hydrologic modeling applications

NASA Astrophysics Data System (ADS)

Liu, Hongli; Tolson, Bryan A.; Craig, James R.; Shafii, Mahyar

2016-12-01

Watershed spatial discretization is an important step in developing a distributed hydrologic model. A key difficulty in the spatial discretization process is maintaining a balance between the aggregation-induced information loss and the increase in computational burden caused by the inclusion of additional computational units. Objective identification of an appropriate discretization scheme still remains a challenge, in part because of the lack of quantitative measures for assessing discretization quality, particularly prior to simulation. This study proposes a priori discretization error metrics to quantify the information loss of any candidate discretization scheme without having to run and calibrate a hydrologic model. These error metrics are applicable to multi-variable and multi-site discretization evaluation and provide directly interpretable information to the hydrologic modeler about discretization quality. The first metric, a subbasin error metric, quantifies the routing information loss from discretization, and the second, a hydrological response unit (HRU) error metric, improves upon existing a priori metrics by quantifying the information loss due to changes in land cover or soil type property aggregation. The metrics are straightforward to understand and easy to recode. Informed by the error metrics, a two-step discretization decision-making approach is proposed with the advantage of reducing extreme errors and meeting the user-specified discretization error targets. The metrics and decision-making approach are applied to the discretization of the Grand River watershed in Ontario, Canada. Results show that information loss increases as discretization gets coarser. Moreover, results help to explain the modeling difficulties associated with smaller upstream subbasins since the worst discretization errors and highest error variability appear in smaller upstream areas instead of larger downstream drainage areas. Hydrologic modeling experiments under candidate discretization schemes validate the strong correlation between the proposed discretization error metrics and hydrologic simulation responses. Discretization decision-making results show that the common and convenient approach of making uniform discretization decisions across the watershed performs worse than the proposed non-uniform discretization approach in terms of preserving spatial heterogeneity under the same computational cost.

Self-Concealment, Avoidance of Psychological Services, and Perceived Likelihood of Seeking Professional Help.

ERIC Educational Resources Information Center

Cepeda-Benito, Antonio; Short, Paul

1998-01-01

New information about the role of self-concealment in the decision to seek psychological services is investigated. Different types of distress selectively predict students' perceived likelihood of seeking help according to the problems for which help would be sought (N=732). Results are discussed in contrast to previous researchers' findings. (EMK)

Concealment of Child Sexual Abuse in Sports

ERIC Educational Resources Information Center

Hartill, Mike

2013-01-01

When the sexual abuse of children is revealed, it is often found that other nonabusing adults were aware of the abuse but failed to act. During the past twenty years or so, the concealment of child sexual abuse (CSA) within organizations has emerged as a key challenge for child protection work. Recent events at Pennsylvania State University (PSU)…

University Presidents' Perceptions and Practice Regarding the Carrying of Concealed Handguns on College Campuses

ERIC Educational Resources Information Center

Price, James H.; Thompson, Amy; Khubchandani, Jagdish; Dake, Joseph; Payton, Erica; Teeple, Karen

2014-01-01

Objective: To assess the perceptions and practices of a national sample of college and university presidents regarding their support for concealed handguns being carried on college campuses. Participants: The sample for this study consisted of a national random sample of 900 college or university presidents. Methods: In the spring of 2013, a…

Guns on Campus: A Current Debate. E-Fact Sheet

ERIC Educational Resources Information Center

Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2010

2010-01-01

Almost all U.S. college campuses ban concealed weapons. But in the aftermath of the tragic shooting deaths at Virginia Tech in 2007, the debate on whether guns should be permitted at colleges and universities has intensified. Dozens of states have considered proposals to lift bans on concealed weapons at colleges and universities, but so far none…

Color digital lensless holographic microscopy: laser versus LED illumination.

PubMed

Garcia-Sucerquia, Jorge

2016-08-20

A comparison of the performance of color digital lensless holographic microscopy (CDLHM) as utilized for illumination of RGB lasers or a super-bright white-light LED with a set of spectral filters is presented. As the use of lasers in CDLHM conceals the possibility of having a compact, lightweight, portable, and low cost microscope, and additionally the limited available laser radiation wavelengths limit a real multispectral imaging microscope, here we present the use of super-bright white-light LED and spectral filters for illuminating the sample. The performance of RGB laser-CDLHM and LED-CDLHM is evaluated on imaging a section of the head of a Drosophila melanogaster fly. This comparison shows that there is trade-off between the spatial resolution of the microscope and the light sources utilized, which can be understood with regard to the coherence properties of the illuminating light. Despite the smaller spatial coherence features of LED-CDLHM in comparison with laser-CDLHM, the former shows promise as a portable RGB digital lensless holographic microscope that could be extended to other wavelengths by the use of different spectral filters.

Effects of Head Rotation on Space- and Word-Based Reading Errors in Spatial Neglect

ERIC Educational Resources Information Center

Reinhart, Stefan; Keller, Ingo; Kerkhoff, Georg

2010-01-01

Patients with right hemisphere lesions often omit or misread words on the left side of a text or the beginning letters of single words which is termed neglect dyslexia (ND). Two types of reading errors are typically observed in ND: omissions and word-based reading errors. The prior are considered as space-based omission errors on the…

Estimating pixel variances in the scenes of staring sensors

DOEpatents

Simonson, Katherine M [Cedar Crest, NM; Ma, Tian J [Albuquerque, NM

2012-01-24

A technique for detecting changes in a scene perceived by a staring sensor is disclosed. The technique includes acquiring a reference image frame and a current image frame of a scene with the staring sensor. A raw difference frame is generated based upon differences between the reference image frame and the current image frame. Pixel error estimates are generated for each pixel in the raw difference frame based at least in part upon spatial error estimates related to spatial intensity gradients in the scene. The pixel error estimates are used to mitigate effects of camera jitter in the scene between the current image frame and the reference image frame.

Every photon counts: improving low, mid, and high-spatial frequency errors on astronomical optics and materials with MRF

NASA Astrophysics Data System (ADS)

Maloney, Chris; Lormeau, Jean Pierre; Dumas, Paul

2016-07-01

Many astronomical sensing applications operate in low-light conditions; for these applications every photon counts. Controlling mid-spatial frequencies and surface roughness on astronomical optics are critical for mitigating scattering effects such as flare and energy loss. By improving these two frequency regimes higher contrast images can be collected with improved efficiency. Classically, Magnetorheological Finishing (MRF) has offered an optical fabrication technique to correct low order errors as well has quilting/print-through errors left over in light-weighted optics from conventional polishing techniques. MRF is a deterministic, sub-aperture polishing process that has been used to improve figure on an ever expanding assortment of optical geometries, such as planos, spheres, on and off axis aspheres, primary mirrors and freeform optics. Precision optics are routinely manufactured by this technology with sizes ranging from 5-2,000mm in diameter. MRF can be used for form corrections; turning a sphere into an asphere or free form, but more commonly for figure corrections achieving figure errors as low as 1nm RMS while using careful metrology setups. Recent advancements in MRF technology have improved the polishing performance expected for astronomical optics in low, mid and high spatial frequency regimes. Deterministic figure correction with MRF is compatible with most materials, including some recent examples on Silicon Carbide and RSA905 Aluminum. MRF also has the ability to produce `perfectly-bad' compensating surfaces, which may be used to compensate for measured or modeled optical deformation from sources such as gravity or mounting. In addition, recent advances in MRF technology allow for corrections of mid-spatial wavelengths as small as 1mm simultaneously with form error correction. Efficient midspatial frequency corrections make use of optimized process conditions including raster polishing in combination with a small tool size. Furthermore, a novel MRF fluid, called C30, has been developed to finish surfaces to ultra-low roughness (ULR) and has been used as the low removal rate fluid required for fine figure correction of mid-spatial frequency errors. This novel MRF fluid is able to achieve <4Å RMS on Nickel-plated Aluminum and even <1.5Å RMS roughness on Silicon, Fused Silica and other materials. C30 fluid is best utilized within a fine figure correction process to target mid-spatial frequency errors as well as smooth surface roughness 'for free' all in one step. In this paper we will discuss recent advancements in MRF technology and the ability to meet requirements for precision optics in low, mid and high spatial frequency regimes and how improved MRF performance addresses the need for achieving tight specifications required for astronomical optics.

Stitching-error reduction in gratings by shot-shifted electron-beam lithography

NASA Technical Reports Server (NTRS)

Dougherty, D. J.; Muller, R. E.; Maker, P. D.; Forouhar, S.

2001-01-01

Calculations of the grating spatial-frequency spectrum and the filtering properties of multiple-pass electron-beam writing demonstrate a tradeoff between stitching-error suppression and minimum pitch separation. High-resolution measurements of optical-diffraction patterns show a 25-dB reduction in stitching-error side modes.

Merging gauge and satellite rainfall with specification of associated uncertainty across Australia

NASA Astrophysics Data System (ADS)

Woldemeskel, Fitsum M.; Sivakumar, Bellie; Sharma, Ashish

2013-08-01

Accurate estimation of spatial rainfall is crucial for modelling hydrological systems and planning and management of water resources. While spatial rainfall can be estimated either using rain gauge-based measurements or using satellite-based measurements, such estimates are subject to uncertainties due to various sources of errors in either case, including interpolation and retrieval errors. The purpose of the present study is twofold: (1) to investigate the benefit of merging rain gauge measurements and satellite rainfall data for Australian conditions and (2) to produce a database of retrospective rainfall along with a new uncertainty metric for each grid location at any timestep. The analysis involves four steps: First, a comparison of rain gauge measurements and the Tropical Rainfall Measuring Mission (TRMM) 3B42 data at such rain gauge locations is carried out. Second, gridded monthly rain gauge rainfall is determined using thin plate smoothing splines (TPSS) and modified inverse distance weight (MIDW) method. Third, the gridded rain gauge rainfall is merged with the monthly accumulated TRMM 3B42 using a linearised weighting procedure, the weights at each grid being calculated based on the error variances of each dataset. Finally, cross validation (CV) errors at rain gauge locations and standard errors at gridded locations for each timestep are estimated. The CV error statistics indicate that merging of the two datasets improves the estimation of spatial rainfall, and more so where the rain gauge network is sparse. The provision of spatio-temporal standard errors with the retrospective dataset is particularly useful for subsequent modelling applications where input error knowledge can help reduce the uncertainty associated with modelling outcomes.

Combined fabrication technique for high-precision aspheric optical windows

NASA Astrophysics Data System (ADS)

Hu, Hao; Song, Ci; Xie, Xuhui

2016-07-01

Specifications made on optical components are becoming more and more stringent with the performance improvement of modern optical systems. These strict requirements not only involve low spatial frequency surface accuracy, mid-and-high spatial frequency surface errors, but also surface smoothness and so on. This presentation mainly focuses on the fabrication process for square aspheric window which combines accurate grinding, magnetorheological finishing (MRF) and smoothing polishing (SP). In order to remove the low spatial frequency surface errors and subsurface defects after accurate grinding, the deterministic polishing method MRF with high convergence and stable material removal rate is applied. Then the SP technology with pseudo-random path is adopted to eliminate the mid-and-high spatial frequency surface ripples and high slope errors which is the defect for MRF. Additionally, the coordinate measurement method and interferometry are combined in different phase. Acid-etched method and ion beam figuring (IBF) are also investigated on observing and reducing the subsurface defects. Actual fabrication result indicates that the combined fabrication technique can lead to high machining efficiency on manufaturing the high-precision and high-quality optical aspheric windows.

A New Stratified Sampling Procedure which Decreases Error Estimation of Varroa Mite Number on Sticky Boards.

PubMed

Kretzschmar, A; Durand, E; Maisonnasse, A; Vallon, J; Le Conte, Y

2015-06-01

A new procedure of stratified sampling is proposed in order to establish an accurate estimation of Varroa destructor populations on sticky bottom boards of the hive. It is based on the spatial sampling theory that recommends using regular grid stratification in the case of spatially structured process. The distribution of varroa mites on sticky board being observed as spatially structured, we designed a sampling scheme based on a regular grid with circles centered on each grid element. This new procedure is then compared with a former method using partially random sampling. Relative error improvements are exposed on the basis of a large sample of simulated sticky boards (n=20,000) which provides a complete range of spatial structures, from a random structure to a highly frame driven structure. The improvement of varroa mite number estimation is then measured by the percentage of counts with an error greater than a given level. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Memory Detection 2.0: The First Web-Based Memory Detection Test

PubMed Central

Kleinberg, Bennett; Verschuere, Bruno

2015-01-01

There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262) tried to hide 2 high salient (birthday, country of origin) and 2 low salient (favourite colour, favourite animal) autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research. PMID:25874966

Automatic specular reflections removal for endoscopic images

NASA Astrophysics Data System (ADS)

Tan, Ke; Wang, Bin; Gao, Yuan

2017-07-01

Endoscopy imaging is utilized to provide a realistic view about the surfaces of organs inside the human body. Owing to the damp internal environment, these surfaces usually have a glossy appearance showing specular reflections. For many computer vision algorithms, the highlights created by specular reflections may become a significant source of error. In this paper, we present a novel method for restoration of the specular reflection regions from a single image. Specular restoration process starts with generating a substitute specular-free image with RPCA method. Then the specular removed image was obtained by taking the binary weighting template of highlight regions as the weighting for merging the original specular image and the substitute image. The modified template was furthermore discussed for the concealment of artificial effects in the edge of specular regions. Experimental results on the removal of the endoscopic image with specular reflections demonstrate the efficiency of the proposed method comparing to the existing methods.

Scientific journal publishes second eratum regarding false information by scientists funded by asbestos interests.

PubMed

Ruff, Kathleen; Mirabelli, Dario; Magnani, Corrado

2016-01-01

In a paper published on Epidemiology, Biostatistics and Public Health, Ilgren et al. claimed that cases of mesothelioma among workers of the Balangero (a municipality of the province of Turin, Northern Italy) chrysotile mine and nearby residents were not caused by chrysotile, but by other forms of asbestos. In support, they cited a reference where no pertaining evidence can be found. One year after the paper, an erratum was published by the journal editors in chief, warning that an erroneous citation was present. The erratum is weak and misleading, concealing the fact that a false statement was supported by such error and that it may serve the interests of the chrysotile industry, by dismissing evidence of chrysotile carcinogenicity. Some of the article authors, of the editors in chief and members of the journal editorial board had financial ties to asbestos interests.

[Complications in pediatric anesthesia].

PubMed

Becke, K

2014-07-01

As in adult anesthesia, morbidity and mortality could be significantly reduced in pediatric anesthesia in recent decades. This fact cannot conceal the fact that the incidence of anesthetic complications in children is still much more common than in adults and sometimes with a severe outcome. Newborns and infants in particular but also children with emergency interventions and severe comorbidities are at increased risk of potential complications. Typical complications in pediatric anesthesia are respiratory problems, medication errors, difficulties with the intravenous puncture and pulmonal aspiration. In the postoperative setting, nausea and vomiting, pain, and emergence delirium can be mentioned as typical complications. In addition to the systematic prevention of complications in pediatric anesthesia, it is important to quickly recognize disturbances of homeostasis and treat them promptly and appropriately. In addition to the expertise of the performing anesthesia team, the institutional structure in particular can improve quality and safety in pediatric anesthesia.

Concealing their communication: exploring psychosocial predictors of young drivers' intentions and engagement in concealed texting.

PubMed

Gauld, Cassandra S; Lewis, Ioni; White, Katherine M

2014-01-01

Making a conscious effort to hide the fact that you are texting while driving (i.e., concealed texting) is a deliberate and risky behaviour involving attention diverted away from the road. As the most frequent users of text messaging services and mobile phones while driving, young people appear at heightened risk of crashing from engaging in this behaviour. This study investigated the phenomenon of concealed texting while driving, and utilised an extended Theory of Planned Behaviour (TPB) including the additional predictors of moral norm, mobile phone involvement, and anticipated regret to predict young drivers' intentions and subsequent behaviour. Participants (n=171) were aged 17-25 years, owned a mobile phone, and had a current driver's licence. Participants completed a questionnaire measuring their intention to conceal texting while driving, and a follow-up questionnaire a week later to report their behavioural engagement. The results of hierarchical multiple regression analyses showed overall support for the predictive utility of the TPB with the standard constructs accounting for 69% of variance in drivers' intentions, and the extended predictors contributing an additional 6% of variance in intentions over and above the standard constructs. Attitude, subjective norm, PBC, moral norm, and mobile phone involvement emerged as significant predictors of intentions; and intention was the only significant predictor of drivers' self-reported behaviour. These constructs can provide insight into key focal points for countermeasures including advertising and other public education strategies aimed at influencing young drivers to reconsider their engagement in this risky behaviour. Copyright © 2013 Elsevier Ltd. All rights reserved.

The formulation and estimation of a spatial skew-normal generalized ordered-response model.

DOT National Transportation Integrated Search

2016-06-01

This paper proposes a new spatial generalized ordered response model with skew-normal kernel error terms and an : associated estimation method. It contributes to the spatial analysis field by allowing a flexible and parametric skew-normal : distribut...

Effects of errors and gaps in spatial data sets on assessment of conservation progress.

PubMed

Visconti, P; Di Marco, M; Álvarez-Romero, J G; Januchowski-Hartley, S R; Pressey, R L; Weeks, R; Rondinini, C

2013-10-01

Data on the location and extent of protected areas, ecosystems, and species' distributions are essential for determining gaps in biodiversity protection and identifying future conservation priorities. However, these data sets always come with errors in the maps and associated metadata. Errors are often overlooked in conservation studies, despite their potential negative effects on the reported extent of protection of species and ecosystems. We used 3 case studies to illustrate the implications of 3 sources of errors in reporting progress toward conservation objectives: protected areas with unknown boundaries that are replaced by buffered centroids, propagation of multiple errors in spatial data, and incomplete protected-area data sets. As of 2010, the frequency of protected areas with unknown boundaries in the World Database on Protected Areas (WDPA) caused the estimated extent of protection of 37.1% of the terrestrial Neotropical mammals to be overestimated by an average 402.8% and of 62.6% of species to be underestimated by an average 10.9%. Estimated level of protection of the world's coral reefs was 25% higher when using recent finer-resolution data on coral reefs as opposed to globally available coarse-resolution data. Accounting for additional data sets not yet incorporated into WDPA contributed up to 6.7% of additional protection to marine ecosystems in the Philippines. We suggest ways for data providers to reduce the errors in spatial and ancillary data and ways for data users to mitigate the effects of these errors on biodiversity assessments. © 2013 Society for Conservation Biology.

Accuracy and Spatial Variability in GPS Surveying for Landslide Mapping on Road Inventories at a Semi-Detailed Scale: the Case in Colombia

NASA Astrophysics Data System (ADS)

Murillo Feo, C. A.; Martnez Martinez, L. J.; Correa Muñoz, N. A.

2016-06-01

The accuracy of locating attributes on topographic surfaces when, using GPS in mountainous areas, is affected by obstacles to wave propagation. As part of this research on the semi-automatic detection of landslides, we evaluate the accuracy and spatial distribution of the horizontal error in GPS positioning in the tertiary road network of six municipalities located in mountainous areas in the department of Cauca, Colombia, using geo-referencing with GPS mapping equipment and static-fast and pseudo-kinematic methods. We obtained quality parameters for the GPS surveys with differential correction, using a post-processing method. The consolidated database underwent exploratory analyses to determine the statistical distribution, a multivariate analysis to establish relationships and partnerships between the variables, and an analysis of the spatial variability and calculus of accuracy, considering the effect of non-Gaussian distribution errors. The evaluation of the internal validity of the data provide metrics with a confidence level of 95% between 1.24 and 2.45 m in the static-fast mode and between 0.86 and 4.2 m in the pseudo-kinematic mode. The external validity had an absolute error of 4.69 m, indicating that this descriptor is more critical than precision. Based on the ASPRS standard, the scale obtained with the evaluated equipment was in the order of 1:20000, a level of detail expected in the landslide-mapping project. Modelling the spatial variability of the horizontal errors from the empirical semi-variogram analysis showed predictions errors close to the external validity of the devices.

Detecting concealed objects at a checkpoint

DOEpatents

McMakin, Douglas L [Richland, WA; Hall, Thomas E [Kennewick, WA; Sheen, David M [Richland, WA; Severtsen, Ronald H [Richland, WA

2008-07-29

Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed object is being carried. This determination includes establishing data corresponding to an image of the individual with a pair of opposed, semi-cylindrical array panels each configured to interrogate the individual with electromagnetic radiation in the 200 MHz to 1 THz range.

The Disclosure Processes Model: Understanding Disclosure Decision Making and Postdisclosure Outcomes among People Living with a Concealable Stigmatized Identity

ERIC Educational Resources Information Center

Chaudoir, Stephenie R.; Fisher, Jeffrey D.

2010-01-01

Disclosure is a critical aspect of the experience of people who live with concealable stigmatized identities. This article presents the disclosure processes model (DPM)--a framework with which to examine when and why interpersonal disclosure may be beneficial. The DPM suggests that antecedent goals representing approach and avoidance motivational…

How Many More Guns?: Estimating the Effect of Allowing Licensed Concealed Handguns on a College Campus

ERIC Educational Resources Information Center

Bouffard, Jeffrey A.; Nobles, Matt R.; Wells, William; Cavanaugh, Michael R.

2012-01-01

Among other arguments, advocates for lifting bans on carrying concealed handguns on campus propose that this would increase the prevalence of legitimately carried handguns, which might then deter crimes or be used to intervene in campus shooting incidents like the one that took place at Virginia Tech in 2007. Opponents suggest that increased…

Mental Health Stigma, Self-Concealment, and Help-Seeking Attitudes among Asian American and European American College Students with No Help-Seeking Experience

ERIC Educational Resources Information Center

Masuda, Akihiko; Boone, Matthew S.

2011-01-01

The present study examined whether mental health stigma (i.e., negative attitudes toward people with a psychological disorder) and self-concealment are unique predictors of help-seeking attitudes in Asian American and European American college students with no history of seeking professional psychological services. The Asian American group had…

Fear Perceptions in Public Parks: Interactions of Environmental Concealment, the Presence of People Recreating, and Gender

ERIC Educational Resources Information Center

Jorgensen, Lisa J.; Ellis, Gary D.; Ruddell, Edward

2013-01-01

This research examined the effect of concealment (environmental cues), presence or absence of people recreating (social cues), and gender on individuals' fear of crime in a community park setting. Using a 7-point single-item indicator, 732 participants from two samples (540 park visitors and 192 college students) rated their estimates of fear of…

Forum: The Future of Instructional Communication. Guns on Campus: Creating Research to Inform Practice

ERIC Educational Resources Information Center

Horan, Sean M.; Bryant, Leah E.

2017-01-01

This essay encourages research on the presence of guns in college classrooms. Readers are asked to consider that around 11 million individuals have concealed carry permits (Crime Prevention Research Center, 2014), and roughly 20% of states allow concealed guns on campus (e.g., Anderson, 2016). Given the centrality of guns in our culture, and…

Mental Health Stigma and Self-Concealment as Predictors of Help-Seeking Attitudes among Latina/o College Students in the United States

ERIC Educational Resources Information Center

Mendoza, Hadrian; Masuda, Akihiko; Swartout, Kevin M.

2015-01-01

The study examined whether mental health stigma and self-concealment are uniquely related to various dimensions of attitudes toward seeking professional psychological services (i.e., help-seeking attitudes) in Latina/o college students. Data from 129 Latina/o undergraduates (76% female) were used in the analysis. Results revealed that mental…

A technique for evaluating the influence of spatial sampling on the determination of global mean total columnar ozone

NASA Technical Reports Server (NTRS)

Tolson, R. H.

1981-01-01

A technique is described for providing a means of evaluating the influence of spatial sampling on the determination of global mean total columnar ozone. A finite number of coefficients in the expansion are determined, and the truncated part of the expansion is shown to contribute an error to the estimate, which depends strongly on the spatial sampling and is relatively insensitive to data noise. First and second order statistics are derived for each term in a spherical harmonic expansion which represents the ozone field, and the statistics are used to estimate systematic and random errors in the estimates of total ozone.

Self-stigma among concealable minorities in Hong Kong: conceptualization and unified measurement.

PubMed

Mak, Winnie W S; Cheung, Rebecca Y M

2010-04-01

Self-stigma refers to the internalized stigma that individuals may have toward themselves as a result of their minority status. Not only can self-stigma dampen the mental health of individuals, it can deter them from seeking professional help lest disclosing their minority status lead to being shunned by service providers. No unified instrument has been developed to measure consistently self-stigma that could be applied to different concealable minority groups. The present study presented findings based on 4 studies on the development and validation of the Self-Stigma Scale, conducted in Hong Kong with community samples of mental health consumers, recent immigrants from Mainland China, and sexual minorities. Upon a series of validation procedures, a 9-item Self-Stigma Scale-Short Form was developed. Initial support on its reliability and construct validity (convergent and criterion validities) were found among 3 stigmatized groups. Utility of this unified measure was to establish an empirical basis upon which self-stigma of different concealable minority groups could be assessed under the same dimensions. Health-care professionals could make use of this short scale to assess potential self-stigmatization among concealable minorities, which may hamper their treatment process as well as their overall well-being.

[Half-gloving cordectomy: a modified procedure for concealed penis].

PubMed

Sun, Wei-Gui; Zheng, Qi-Chuan; Jiang, Kun

2012-06-01

To search for a simple surgical procedure for the treatment of concealed penis that may have better effect and less complications. We used a modified surgical method in the treatment of 58 patients with concealed penis aged from 3 to 15 (mean 6.8) years. The operation was simplified and involved the following steps: wholly unveiling the penis glans, half-degloving the foreskins, cutting off all the adhesive fibers up to the penile suspensory ligaments, and liberating the external penis. The operation was successful in all the patients, with the operative time of 15 -45 (mean 33) minutes, hospital stay of 2 - 5 (mean 3.5) days, but no complications except mild foreskin edema in 5 cases. The external penis was prolonged from 0.5 - 2.8 (mean 1.4) cm preoperatively to 3.2 - 8.5 (mean 3.9) cm postoperatively. The patients were followed up for 1 -3 years, all satisfied with the length and appearance of the penis, and their sexual and reproductive functions were normal. The modified surgical procedure for concealed penis is simple and effective, with desirable outcomes, few postoperative complications and no damage to sexual and reproductive functions.

"When you're in a crisis like that, you don't want people to know": mortgage strain, stigma, and mental health.

PubMed

Keene, Danya E; Cowan, Sarah K; Baker, Amy Castro

2015-05-01

We analyzed experiences of stigmatization, concealment, and isolation among African American homeowners who were experiencing mortgage strain. We conducted semistructured interviews between March 2012 and May 2013 with 28 African American homeowners in a northeastern US city who were experiencing mortgage strain. We coded all of the transcripts and reviewed data for codes relating to stigma, sharing information, social support, social isolation, and the meaning of homeownership. Our data showed that mortgage strain can be a concealable stigma. Participants internalized this stigma, expressing shame about their mortgage situation. Additionally, some participants anticipated that others would view them as less worthy given their mortgage trouble. In an effort to avoid stigmatization, many concealed their mortgage trouble, which often led to isolation. This stigmatization, concealment, and isolation seemed to contribute to participants' depression, anxiety, and emotional distress. Stigma may exacerbate stress associated with mortgage strain and contribute to poor mental health, particularly among upwardly mobile African Americans who have overcome significant structural barriers to home ownership. Reducing stigma associated with mortgage strain may help to reduce the health consequences of this stressful life event.

Examination of an Electronic Patient Record Display Method to Protect Patient Information Privacy.

PubMed

Niimi, Yukari; Ota, Katsumasa

2017-02-01

Electronic patient records facilitate the provision of safe, high-quality medical care. However, because personnel can view almost all stored information, this study designed a display method using a mosaic blur (pixelation) to temporarily conceal information patients do not want shared. This study developed an electronic patient records display method for patient information that balanced the patient's desire for personal information protection against the need for information sharing among medical personnel. First, medical personnel were interviewed about the degree of information required for both individual duties and team-based care. Subsequently, they tested a mock display method that partially concealed information using a mosaic blur, and they were interviewed about the effectiveness of the display method that ensures patient privacy. Participants better understood patients' demand for confidentiality, suggesting increased awareness of patients' privacy protection. However, participants also indicated that temporary concealment of certain information was problematic. Other issues included the inconvenience of removing the mosaic blur to obtain required information and risk of insufficient information for medical care. Despite several issues with using a display method that temporarily conceals information according to patient privacy needs, medical personnel could accept this display method if information essential to medical safety remains accessible.

Crime Modeling using Spatial Regression Approach

NASA Astrophysics Data System (ADS)

Saleh Ahmar, Ansari; Adiatma; Kasim Aidid, M.

2018-01-01

Act of criminality in Indonesia increased both variety and quantity every year. As murder, rape, assault, vandalism, theft, fraud, fencing, and other cases that make people feel unsafe. Risk of society exposed to crime is the number of reported cases in the police institution. The higher of the number of reporter to the police institution then the number of crime in the region is increasing. In this research, modeling criminality in South Sulawesi, Indonesia with the dependent variable used is the society exposed to the risk of crime. Modelling done by area approach is the using Spatial Autoregressive (SAR) and Spatial Error Model (SEM) methods. The independent variable used is the population density, the number of poor population, GDP per capita, unemployment and the human development index (HDI). Based on the analysis using spatial regression can be shown that there are no dependencies spatial both lag or errors in South Sulawesi.

The study design elements employed by researchers in preclinical animal experiments from two research domains and implications for automation of systematic reviews.

PubMed

O'Connor, Annette M; Totton, Sarah C; Cullen, Jonah N; Ramezani, Mahmood; Kalivarapu, Vijay; Yuan, Chaohui; Gilbert, Stephen B

2018-01-01

Systematic reviews are increasingly using data from preclinical animal experiments in evidence networks. Further, there are ever-increasing efforts to automate aspects of the systematic review process. When assessing systematic bias and unit-of-analysis errors in preclinical experiments, it is critical to understand the study design elements employed by investigators. Such information can also inform prioritization of automation efforts that allow the identification of the most common issues. The aim of this study was to identify the design elements used by investigators in preclinical research in order to inform unique aspects of assessment of bias and error in preclinical research. Using 100 preclinical experiments each related to brain trauma and toxicology, we assessed design elements described by the investigators. We evaluated Methods and Materials sections of reports for descriptions of the following design elements: 1) use of comparison group, 2) unit of allocation of the interventions to study units, 3) arrangement of factors, 4) method of factor allocation to study units, 5) concealment of the factors during allocation and outcome assessment, 6) independence of study units, and 7) nature of factors. Many investigators reported using design elements that suggested the potential for unit-of-analysis errors, i.e., descriptions of repeated measurements of the outcome (94/200) and descriptions of potential for pseudo-replication (99/200). Use of complex factor arrangements was common, with 112 experiments using some form of factorial design (complete, incomplete or split-plot-like). In the toxicology dataset, 20 of the 100 experiments appeared to use a split-plot-like design, although no investigators used this term. The common use of repeated measures and factorial designs means understanding bias and error in preclinical experimental design might require greater expertise than simple parallel designs. Similarly, use of complex factor arrangements creates novel challenges for accurate automation of data extraction and bias and error assessment in preclinical experiments.

Spatial interpolation schemes of daily precipitation for hydrologic modeling

USGS Publications Warehouse

Hwang, Y.; Clark, M.R.; Rajagopalan, B.; Leavesley, G.

2012-01-01

Distributed hydrologic models typically require spatial estimates of precipitation interpolated from sparsely located observational points to the specific grid points. We compare and contrast the performance of regression-based statistical methods for the spatial estimation of precipitation in two hydrologically different basins and confirmed that widely used regression-based estimation schemes fail to describe the realistic spatial variability of daily precipitation field. The methods assessed are: (1) inverse distance weighted average; (2) multiple linear regression (MLR); (3) climatological MLR; and (4) locally weighted polynomial regression (LWP). In order to improve the performance of the interpolations, the authors propose a two-step regression technique for effective daily precipitation estimation. In this simple two-step estimation process, precipitation occurrence is first generated via a logistic regression model before estimate the amount of precipitation separately on wet days. This process generated the precipitation occurrence, amount, and spatial correlation effectively. A distributed hydrologic model (PRMS) was used for the impact analysis in daily time step simulation. Multiple simulations suggested noticeable differences between the input alternatives generated by three different interpolation schemes. Differences are shown in overall simulation error against the observations, degree of explained variability, and seasonal volumes. Simulated streamflows also showed different characteristics in mean, maximum, minimum, and peak flows. Given the same parameter optimization technique, LWP input showed least streamflow error in Alapaha basin and CMLR input showed least error (still very close to LWP) in Animas basin. All of the two-step interpolation inputs resulted in lower streamflow error compared to the directly interpolated inputs. ?? 2011 Springer-Verlag.

Open-area concealed-weapon detection system

NASA Astrophysics Data System (ADS)

Pati, P.; Mather, P.

2011-06-01

Concealed Weapon Detection (CWD) has become a significant challenge to present day security needs; individuals carrying weapons into airplanes, schools, and secured establishments are threat to public security. Although controlled screening, of people for concealed weapons, has been employed in many establishments, procedures and equipment are designed to work in restricted environments like airport passport control, military checkpoints, hospitals, school and university entrance. Furthermore, screening systems do not effectively decipher between threat and non-threat metal objects, thus leading to high rate of false alarms which can become a liability to daily operational needs of establishments. Therefore, the design and development of a new CWD system to operate in a large open area environment with large numbers of people reduced incidences of false alarms and increased location accuracy is essential.

Could plate tectonics on Venus be concealed by volcanic deposits

NASA Technical Reports Server (NTRS)

Kaula, W. M.; Muradian, L. M.

1982-01-01

The present investigation is supplementary to a study reported by Kaula and Phillips (1981). From an analysis of Pioneer Venus altimetry, Kaula and Phillips had inferred that any heat loss from the planet by plate tectonics must be small compared to that from the earth. However, it has been suggested by others that plate tectonic may exist on Venus, but that the expected 'square root of s' dependence of the topographic drop off is not observed because it is concealed by lava flows. The present investigation has the objective to conduct an examination whether this suggestion of concealment by lava flow is correct. On the basis of the performed analysis, it is concluded that the results obtained by Kaula and Phillips appear to be well justified.

A simulation study to quantify the impacts of exposure ...

EPA Pesticide Factsheets

BackgroundExposure measurement error in copollutant epidemiologic models has the potential to introduce bias in relative risk (RR) estimates. A simulation study was conducted using empirical data to quantify the impact of correlated measurement errors in time-series analyses of air pollution and health.MethodsZIP-code level estimates of exposure for six pollutants (CO, NOx, EC, PM2.5, SO4, O3) from 1999 to 2002 in the Atlanta metropolitan area were used to calculate spatial, population (i.e. ambient versus personal), and total exposure measurement error.Empirically determined covariance of pollutant concentration pairs and the associated measurement errors were used to simulate true exposure (exposure without error) from observed exposure. Daily emergency department visits for respiratory diseases were simulated using a Poisson time-series model with a main pollutant RR = 1.05 per interquartile range, and a null association for the copollutant (RR = 1). Monte Carlo experiments were used to evaluate the impacts of correlated exposure errors of different copollutant pairs.ResultsSubstantial attenuation of RRs due to exposure error was evident in nearly all copollutant pairs studied, ranging from 10 to 40% attenuation for spatial error, 3–85% for population error, and 31–85% for total error. When CO, NOx or EC is the main pollutant, we demonstrated the possibility of false positives, specifically identifying significant, positive associations for copoll

Extreme Universe Space Observatory (EUSO) Optics Module

NASA Technical Reports Server (NTRS)

Young, Roy; Christl, Mark

2008-01-01

A demonstration part will be manufactured in Japan on one of the large Toshiba machines with a diameter of 2.5 meters. This will be a flat PMMA disk that is cut between 0.5 and 1.25 meters radius. The cut should demonstrate manufacturing the most difficult parts of the 2.5 meter Fresnel pattern and the blazed grating on the diffractive surface. Optical simulations, validated with the subscale prototype, will be used to determine the limits on manufacturing errors (tolerances) that will result in optics that meet EUSO s requirements. There will be limits on surface roughness (or errors at high spatial frequency); radial and azimuthal slope errors (at lower spatial frequencies) and plunge cut depth errors in the blazed grating. The demonstration part will be measured to determine whether it was made within the allowable tolerances.

Spatial cues more salient than color cues in cotton-top tamarins (Saguinus oedipus) reversal learning.

PubMed

Gaudio, Jennifer L; Snowdon, Charles T

2008-11-01

Animals living in stable home ranges have many potential cues to locate food. Spatial and color cues are important for wild Callitrichids (marmosets and tamarins). Field studies have assigned the highest priority to distal spatial cues for determining the location of food resources with color cues serving as a secondary cue to assess relative ripeness, once a food source is located. We tested two hypotheses with captive cotton-top tamarins: (a) Tamarins will demonstrate higher rates of initial learning when rewarded for attending to spatial cues versus color cues. (b) Tamarins will show higher rates of correct responses when transferred from color cues to spatial cues than from spatial cues to color cues. The results supported both hypotheses. Tamarins rewarded based on spatial location made significantly more correct choices and fewer errors than tamarins rewarded based on color cues during initial learning. Furthermore, tamarins trained on color cues showed significantly increased correct responses and decreased errors when cues were reversed to reward spatial cues. Subsequent reversal to color cues induced a regression in performance. For tamarins spatial cues appear more salient than color cues in a foraging task. (PsycINFO Database Record (c) 2008 APA, all rights reserved).

[IR spectral-analysis-based range estimation for an object with small temperature difference from background].

PubMed

Fu, Xiao-Ning; Wang, Jie; Yang, Lin

2013-01-01

It is a typical passive ranging technology that estimation of distance of an object is based on transmission characteristic of infrared radiation, it is also a hotspot in electro-optic countermeasures. Because of avoiding transmitting energy in the detection, this ranging technology will significantly enhance the penetration capability and infrared conceal capability of the missiles or unmanned aerial vehicles. With the current situation in existing passive ranging system, for overcoming the shortage in ranging an oncoming target object with small temperature difference from background, an improved distance estimation scheme was proposed. This article begins with introducing the concept of signal transfer function, makes clear the working curve of current algorithm, and points out that the estimated distance is not unique due to inherent nonlinearity of the working curve. A new distance calculation algorithm was obtained through nonlinear correction technique. It is a ranging formula by using sensing information at 3-5 and 8-12 microm combined with background temperature and field meteorological conditions. The authors' study has shown that the ranging error could be mainly kept around the level of 10% under the condition of the target and background apparent temperature difference equal to +/- 5 K, and the error in estimating background temperature is no more than +/- 15 K.

Digital halftoning methods for selectively partitioning error into achromatic and chromatic channels

NASA Technical Reports Server (NTRS)

Mulligan, Jeffrey B.

1990-01-01

A method is described for reducing the visibility of artifacts arising in the display of quantized color images on CRT displays. The method is based on the differential spatial sensitivity of the human visual system to chromatic and achromatic modulations. Because the visual system has the highest spatial and temporal acuity for the luminance component of an image, a technique which will reduce luminance artifacts at the expense of introducing high-frequency chromatic errors is sought. A method based on controlling the correlations between the quantization errors in the individual phosphor images is explored. The luminance component is greatest when the phosphor errors are positively correlated, and is minimized when the phosphor errors are negatively correlated. The greatest effect of the correlation is obtained when the intensity quantization step sizes of the individual phosphors have equal luminances. For the ordered dither algorithm, a version of the method can be implemented by simply inverting the matrix of thresholds for one of the color components.

Examining Impulse-Variability Theory and the Speed-Accuracy Trade-Off in Children's Overarm Throwing Performance.

PubMed

Molina, Sergio L; Stodden, David F

2018-04-01

This study examined variability in throwing speed and spatial error to test the prediction of an inverted-U function (i.e., impulse-variability [IV] theory) and the speed-accuracy trade-off. Forty-five 9- to 11-year-old children were instructed to throw at a specified percentage of maximum speed (45%, 65%, 85%, and 100%) and hit the wall target. Results indicated no statistically significant differences in variable error across the target conditions (p = .72), failing to support the inverted-U hypothesis. Spatial accuracy results indicated no statistically significant differences with mean radial error (p = .18), centroid radial error (p = .13), and bivariate variable error (p = .08) also failing to support the speed-accuracy trade-off in overarm throwing. As neither throwing performance variability nor accuracy changed across percentages of maximum speed in this sample of children as well as in a previous adult sample, current policy and practices of practitioners may need to be reevaluated.

Disclosure and Concealment of Sexual Orientation and the Mental Health of Non-Gay-Identified, Behaviorally Bisexual Men

ERIC Educational Resources Information Center

Schrimshaw, Eric W.; Siegel, Karolynn; Downing, Martin J., Jr.; Parsons, Jeffrey T.

2013-01-01

Objective: Although bisexual men report lower levels of mental health relative to gay men, few studies have examined the factors that contribute to bisexual men's mental health. Bisexual men are less likely to disclose, and more likely to conceal (i.e., a desire to hide), their sexual orientation than gay men. Theory suggests that this may…

Non-Linear Acoustic Concealed Weapons Detector

DTIC Science & Technology

2006-05-01

signature analysis 8 the interactions of the beams with concealed objects. The Khokhlov- Zabolotskaya-Kuznetsov ( KZK ) equation is the most widely used...Hamilton developed a finite difference method based on the KZK equation to model pulsed acoustic emissions from axial symmetric sources. Using a...College of William & Mary, we have developed a simulation code using the KZK equation to model non-linear acoustic beams and visualize beam patterns

To Be or Not to Be Out in the Classroom: Exploring Communication Privacy Management Strategies of Lesbian, Gay, and Queer College Teachers

ERIC Educational Resources Information Center

McKenna-Buchanan, Tim; Munz, Stevie; Rudnick, Justin

2015-01-01

Lesbian, gay, and queer (LGQ) teachers often deal with the tension between disclosing and concealing their sexual orientations in the college classroom. This article presents the results of a qualitative interview study with 29 self-identified LGQ college teachers about their choices to disclose or conceal their sexual identities. Using…

Self-Concealment, Social Network Sites Usage, Social Appearance Anxiety, Loneliness of High School Students: A Model Testing

ERIC Educational Resources Information Center

Dogan, Ugur; Çolak, Tugba Seda

2016-01-01

This study was tested a model for explain to social networks sites (SNS) usage with structural equation modeling (SEM). Using SEM on a sample of 475 high school students (35% male, 65% female) students, model was investigated the relationship between self-concealment, social appearance anxiety, loneliness on SNS such as Twitter and Facebook usage.…

Syzygies, Pluricanonical Maps, and the Birational Geometry of Varieties of Maximal Albanese Dimension

NASA Astrophysics Data System (ADS)

Tesfagiorgis, Kibrewossen B.

Satellite Precipitation Estimates (SPEs) may be the only available source of information for operational hydrologic and flash flood prediction due to spatial limitations of radar and gauge products in mountainous regions. The present work develops an approach to seamlessly blend satellite, available radar, climatological and gauge precipitation products to fill gaps in ground-based radar precipitation field. To mix different precipitation products, the error of any of the products relative to each other should be removed. For bias correction, the study uses a new ensemble-based method which aims to estimate spatially varying multiplicative biases in SPEs using a radar-gauge precipitation product. Bias factors were calculated for a randomly selected sample of rainy pixels in the study area. Spatial fields of estimated bias were generated taking into account spatial variation and random errors in the sampled values. In addition to biases, sometimes there is also spatial error between the radar and satellite precipitation estimates; one of them has to be geometrically corrected with reference to the other. A set of corresponding raining points between SPE and radar products are selected to apply linear registration using a regularized least square technique to minimize the dislocation error in SPEs with respect to available radar products. A weighted Successive Correction Method (SCM) is used to make the merging between error corrected satellite and radar precipitation estimates. In addition to SCM, we use a combination of SCM and Bayesian spatial method for merging the rain gauges and climatological precipitation sources with radar and SPEs. We demonstrated the method using two satellite-based, CPC Morphing (CMORPH) and Hydro-Estimator (HE), two radar-gauge based, Stage-II and ST-IV, a climatological product PRISM and rain gauge dataset for several rain events from 2006 to 2008 over different geographical locations of the United States. Results show that: (a) the method of ensembles helped reduce biases in SPEs significantly; (b) the SCM method in combination with the Bayesian spatial model produced a precipitation product in good agreement with independent measurements .The study implies that using the available radar pixels surrounding the gap area, rain gauge, PRISM and satellite products, a radar like product is achievable over radar gap areas that benefits the operational meteorology and hydrology community.

Carbon-oxygen isotopes and rare earth elements as an exploration vector for Carlin-type gold deposits: A case study of the Shuiyindong gold deposit, Guizhou Province, SW China

NASA Astrophysics Data System (ADS)

Tan, Qin-Ping; Xia, Yong; Wang, Xueqiu; Xie, Zhuo-Jun; Wei, Dong-Tian

2017-10-01

The Shuiyindong gold deposit is a deeply concealed strata-bound Carlin-type deposit in southwestern Guizhou Province, China. The deposit lies on the eastern limb of the Huijiabao anticline with ores mainly along the anticline axis and hosted in bioclastic limestone, containing calcite veins, of the Permian Longtan Formation units. In this study, we measured carbon and oxygen isotopic ratios and rare earth element (REE) concentrations of the host rocks and calcite veins along a profile across the Shuiyindong deposit. Orebodies in the upper unit of the Longtan Formation have higher δ18O values (20.6-22.4‰) and lower δ13C values (-3.7 to -0.5‰) than the country rocks (δ18O: 18.8-21.4‰; δ13C: -0.7 to 0.8‰). However, there are no obvious trends of δ18O and δ13C values from the country rocks to the orebodies in the middle unit of the Longtan Formation. The spatial distribution of the calcite veins displays distinct halos of δ13C and δ18O values and REE concentrations. Calcite veins along the anticlinal axis and major reverse fault are enriched in Middle REE (Sm, Eu, Gd, and Tb) and 18O and depleted in 13C. Surficial veining calcite-filled fractures/faults that connect to deep concealed strata-bound gold mineralization systems can be vectors toward deep ores in southwestern Guizhou Province, China.

On the sub-model errors of a generalized one-way coupling scheme for linking models at different scales

NASA Astrophysics Data System (ADS)

Zeng, Jicai; Zha, Yuanyuan; Zhang, Yonggen; Shi, Liangsheng; Zhu, Yan; Yang, Jinzhong

2017-11-01

Multi-scale modeling of the localized groundwater flow problems in a large-scale aquifer has been extensively investigated under the context of cost-benefit controversy. An alternative is to couple the parent and child models with different spatial and temporal scales, which may result in non-trivial sub-model errors in the local areas of interest. Basically, such errors in the child models originate from the deficiency in the coupling methods, as well as from the inadequacy in the spatial and temporal discretizations of the parent and child models. In this study, we investigate the sub-model errors within a generalized one-way coupling scheme given its numerical stability and efficiency, which enables more flexibility in choosing sub-models. To couple the models at different scales, the head solution at parent scale is delivered downward onto the child boundary nodes by means of the spatial and temporal head interpolation approaches. The efficiency of the coupling model is improved either by refining the grid or time step size in the parent and child models, or by carefully locating the sub-model boundary nodes. The temporal truncation errors in the sub-models can be significantly reduced by the adaptive local time-stepping scheme. The generalized one-way coupling scheme is promising to handle the multi-scale groundwater flow problems with complex stresses and heterogeneity.

Integrating Map Algebra and Statistical Modeling for Spatio- Temporal Analysis of Monthly Mean Daily Incident Photosynthetically Active Radiation (PAR) over a Complex Terrain.

PubMed

Evrendilek, Fatih

2007-12-12

This study aims at quantifying spatio-temporal dynamics of monthly mean dailyincident photosynthetically active radiation (PAR) over a vast and complex terrain such asTurkey. The spatial interpolation method of universal kriging, and the combination ofmultiple linear regression (MLR) models and map algebra techniques were implemented togenerate surface maps of PAR with a grid resolution of 500 x 500 m as a function of fivegeographical and 14 climatic variables. Performance of the geostatistical and MLR modelswas compared using mean prediction error (MPE), root-mean-square prediction error(RMSPE), average standard prediction error (ASE), mean standardized prediction error(MSPE), root-mean-square standardized prediction error (RMSSPE), and adjustedcoefficient of determination (R² adj. ). The best-fit MLR- and universal kriging-generatedmodels of monthly mean daily PAR were validated against an independent 37-year observeddataset of 35 climate stations derived from 160 stations across Turkey by the Jackknifingmethod. The spatial variability patterns of monthly mean daily incident PAR were moreaccurately reflected in the surface maps created by the MLR-based models than in thosecreated by the universal kriging method, in particular, for spring (May) and autumn(November). The MLR-based spatial interpolation algorithms of PAR described in thisstudy indicated the significance of the multifactor approach to understanding and mappingspatio-temporal dynamics of PAR for a complex terrain over meso-scales.

Not to put too fine a point on it - does increasing precision of geographic referencing improve species distribution models for a wide-ranging migratory bat?

USGS Publications Warehouse

Hayes, Mark A.; Ozenberger, Katharine; Cryan, Paul M.; Wunder, Michael B.

2015-01-01

Bat specimens held in natural history museum collections can provide insights into the distribution of species. However, there are several important sources of spatial error associated with natural history specimens that may influence the analysis and mapping of bat species distributions. We analyzed the importance of geographic referencing and error correction in species distribution modeling (SDM) using occurrence records of hoary bats (Lasiurus cinereus). This species is known to migrate long distances and is a species of increasing concern due to fatalities documented at wind energy facilities in North America. We used 3,215 museum occurrence records collected from 1950–2000 for hoary bats in North America. We compared SDM performance using five approaches: generalized linear models, multivariate adaptive regression splines, boosted regression trees, random forest, and maximum entropy models. We evaluated results using three SDM performance metrics (AUC, sensitivity, and specificity) and two data sets: one comprised of the original occurrence data, and a second data set consisting of these same records after the locations were adjusted to correct for identifiable spatial errors. The increase in precision improved the mean estimated spatial error associated with hoary bat records from 5.11 km to 1.58 km, and this reduction in error resulted in a slight increase in all three SDM performance metrics. These results provide insights into the importance of geographic referencing and the value of correcting spatial errors in modeling the distribution of a wide-ranging bat species. We conclude that the considerable time and effort invested in carefully increasing the precision of the occurrence locations in this data set was not worth the marginal gains in improved SDM performance, and it seems likely that gains would be similar for other bat species that range across large areas of the continent, migrate, and are habitat generalists.

Holographic radar imaging privacy techniques utilizing dual-frequency implementation

NASA Astrophysics Data System (ADS)

McMakin, Douglas L.; Hall, Thomas E.; Sheen, David M.

2008-04-01

Over the last 15 years, the Pacific Northwest National Laboratory has performed significant research and development activities to enhance the state of the art of holographic radar imaging systems to be used at security checkpoints for screening people for concealed threats hidden under their garments. These enhancement activities included improvements to privacy techniques to remove human features and providing automatic detection of body-worn concealed threats. The enhanced privacy and detection methods used both physical and software imaging techniques. The physical imaging techniques included polarization-diversity illumination and reception, dual-frequency implementation, and high-frequency imaging at 60 GHz. Software imaging techniques to enhance the privacy of the person under surveillance included extracting concealed threat artifacts from the imagery to automatically detect the threat. This paper will focus on physical privacy techniques using dual-frequency implementation.

Photonic generation of polarization-resolved wideband chaos with time-delay concealment in three-cascaded vertical-cavity surface-emitting lasers.

PubMed

Liu, Huijie; Li, Nianqiang; Zhao, Qingchun

2015-05-10

Optical chaos generated by chaotic lasers has been widely used in several important applications, such as chaos-based communications and high-speed random-number generators. However, these applications are susceptible to degradation by the presence of time-delay (TD) signature identified from the chaotic output. Here we propose to achieve the concealment of TD signature, along with the enhancement of chaos bandwidth, in three-cascaded vertical-cavity surface-emitting lasers (VCSELs). The cascaded system is composed of an external-cavity master VCSEL, a solitary intermediate VCSEL, and a solitary slave VCSEL. Through mapping the evolutions of TD signature and chaos bandwidth in the parameter space of the injection strength and frequency detuning, photonic generation of polarization-resolved wideband chaos with TD concealment is numerically demonstrated for wide regions of the injection parameters.

Holographic Radar Imaging Privacy Techniques Utilizing Dual-Frequency Implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMakin, Douglas L.; Hall, Thomas E.; Sheen, David M.

2008-04-18

Over the last 15 years, the Pacific Northwest National Laboratory has performed significant research and development activities to enhance the state of the art of holographic radar imaging systems to be used at security checkpoints for screening people for concealed threats hidden under their garments. These enhancement activities included improvements to privacy techniques to remove human features and providing automatic detection of body-worn concealed threats. The enhanced privacy and detection methods used both physical and software imaging techniques. The physical imaging techniques included polarization-diversity illumination and reception, dual-frequency implementation, and high-frequency imaging at 60 GHz. Software imaging techniques to enhancemore » the privacy of the person under surveillance included extracting concealed threat artifacts from the imagery to automatically detect the threat. This paper will focus on physical privacy techniques using dual-frequency implementation.« less

How Men Manage Bulbar Urethral Stricture by Concealing Urinary Symptoms.

PubMed

Whybrow, Paul; Rapley, Tim; Pickard, Robert; Hrisos, Susan

2015-10-01

In this article, we present findings from research conducted as part of a multi-center surgical trial. Bulbar urethral stricture, a narrowing of the middle urethra, is a common cause of urinary problems in men that can have a profound impact on their lives. Semi-structured interviews were conducted with a sample of 19 men seeking treatment for urethral stricture. The findings reveal how men tend to develop routines and tactics to adapt to their symptoms and hide them from others rather than seek help. We argue that this concealment becomes an inseparable part of how the disease is managed and is an additional hidden practical and emotional burden for these men. In addition, we suggest that the patients only sought curative treatments once practices of social concealment are no longer viable. © The Author(s) 2015.

Induction detection of concealed bulk banknotes

NASA Astrophysics Data System (ADS)

Fuller, Christopher; Chen, Antao

2012-06-01

The smuggling of bulk cash across borders is a serious issue that has increased in recent years. In an effort to curb the illegal transport of large numbers of paper bills, a detection scheme has been developed, based on the magnetic characteristics of bank notes. The results show that volumes of paper currency can be detected through common concealing materials such as plastics, cardboard, and fabrics making it a possible potential addition to border security methods. The detection scheme holds the potential of also reducing or eliminating false positives caused by metallic materials found in the vicinity, by observing the stark difference in received signals caused by metal and currency. The detection scheme holds the potential to detect for both the presence and number of concealed bulk notes, while maintaining the ability to reduce false positives caused by metal objects.

Design of a steganographic virtual operating system

NASA Astrophysics Data System (ADS)

Ashendorf, Elan; Craver, Scott

2015-03-01

A steganographic file system is a secure file system whose very existence on a disk is concealed. Customarily, these systems hide an encrypted volume within unused disk blocks, slack space, or atop conventional encrypted volumes. These file systems are far from undetectable, however: aside from their ciphertext footprint, they require a software or driver installation whose presence can attract attention and then targeted surveillance. We describe a new steganographic operating environment that requires no visible software installation, launching instead from a concealed bootstrap program that can be extracted and invoked with a chain of common Unix commands. Our system conceals its payload within innocuous files that typically contain high-entropy data, producing a footprint that is far less conspicuous than existing methods. The system uses a local web server to provide a file system, user interface and applications through a web architecture.

Spatial perception predicts laparoscopic skills on virtual reality laparoscopy simulator.

PubMed

Hassan, I; Gerdes, B; Koller, M; Dick, B; Hellwig, D; Rothmund, M; Zielke, A

2007-06-01

This study evaluates the influence of visual-spatial perception on laparoscopic performance of novices with a virtual reality simulator (LapSim(R)). Twenty-four novices completed standardized tests of visual-spatial perception (Lameris Toegepaste Natuurwetenschappelijk Onderzoek [TNO] Test(R) and Stumpf-Fay Cube Perspectives Test(R)) and laparoscopic skills were assessed objectively, while performing 1-h practice sessions on the LapSim(R), comprising of coordination, cutting, and clip application tasks. Outcome variables included time to complete the tasks, economy of motion as well as total error scores, respectively. The degree of visual-spatial perception correlated significantly with laparoscopic performance on the LapSim(R) scores. Participants with a high degree of spatial perception (Group A) performed the tasks faster than those (Group B) who had a low degree of spatial perception (p = 0.001). Individuals with a high degree of spatial perception also scored better for economy of motion (p = 0.021), tissue damage (p = 0.009), and total error (p = 0.007). Among novices, visual-spatial perception is associated with manual skills performed on a virtual reality simulator. This result may be important for educators to develop adequate training programs that can be individually adapted.

What aspects of vision facilitate haptic processing?

PubMed

Millar, Susanna; Al-Attar, Zainab

2005-12-01

We investigate how vision affects haptic performance when task-relevant visual cues are reduced or excluded. The task was to remember the spatial location of six landmarks that were explored by touch in a tactile map. Here, we use specially designed spectacles that simulate residual peripheral vision, tunnel vision, diffuse light perception, and total blindness. Results for target locations differed, suggesting additional effects from adjacent touch cues. These are discussed. Touch with full vision was most accurate, as expected. Peripheral and tunnel vision, which reduce visuo-spatial cues, differed in error pattern. Both were less accurate than full vision, and significantly more accurate than touch with diffuse light perception, and touch alone. The important finding was that touch with diffuse light perception, which excludes spatial cues, did not differ from touch without vision in performance accuracy, nor in location error pattern. The contrast between spatially relevant versus spatially irrelevant vision provides new, rather decisive, evidence against the hypothesis that vision affects haptic processing even if it does not add task-relevant information. The results support optimal integration theories, and suggest that spatial and non-spatial aspects of vision need explicit distinction in bimodal studies and theories of spatial integration.

Fast scattering simulation tool for multi-energy x-ray imaging

NASA Astrophysics Data System (ADS)

Sossin, A.; Tabary, J.; Rebuffel, V.; Létang, J. M.; Freud, N.; Verger, L.

2015-12-01

A combination of Monte Carlo (MC) and deterministic approaches was employed as a means of creating a simulation tool capable of providing energy resolved x-ray primary and scatter images within a reasonable time interval. Libraries of Sindbad, a previously developed x-ray simulation software, were used in the development. The scatter simulation capabilities of the tool were validated through simulation with the aid of GATE and through experimentation by using a spectrometric CdTe detector. A simple cylindrical phantom with cavities and an aluminum insert was used. Cross-validation with GATE showed good agreement with a global spatial error of 1.5% and a maximum scatter spectrum error of around 6%. Experimental validation also supported the accuracy of the simulations obtained from the developed software with a global spatial error of 1.8% and a maximum error of around 8.5% in the scatter spectra.

The challenge of estimating the SWOT signal and error spectra over the Ocean and its applications to CalVal and state estimation problems

NASA Astrophysics Data System (ADS)

Ubelmann, C.; Gerald, D.

2016-12-01

The SWOT data validation will be a first challenge after launch, as the nature of the measurement, in particular the two-dimensionality at short spatial scales, is new in altimetry. If the comparison with independent observations may be locally possible, a validation of the full signal and error spectrum will be challenging. However, some recent analyses in simulations have shown the possibility to separate the geophysical signals from the spatially coherent instrumental errors in the spectral space, through cross-spectral analysis. These results suggest that rapidly after launch, the instrument error canl be spectrally separated providing some validations and insights on the Ocean energy spectrum, as well as optimal calibrations. Beyond CalVal, such spectral computations will be also essential for producing high-level Ocean estimates (two and three dimensional Ocean state reconstructions).

Analytic score distributions for a spatially continuous tridirectional Monte Carol transport problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Booth, T.E.

1996-01-01

The interpretation of the statistical error estimates produced by Monte Carlo transport codes is still somewhat of an art. Empirically, there are variance reduction techniques whose error estimates are almost always reliable, and there are variance reduction techniques whose error estimates are often unreliable. Unreliable error estimates usually result from inadequate large-score sampling from the score distribution`s tail. Statisticians believe that more accurate confidence interval statements are possible if the general nature of the score distribution can be characterized. Here, the analytic score distribution for the exponential transform applied to a simple, spatially continuous Monte Carlo transport problem is provided.more » Anisotropic scattering and implicit capture are included in the theory. In large part, the analytic score distributions that are derived provide the basis for the ten new statistical quality checks in MCNP.« less

A simulation study to quantify the impacts of exposure measurement error on air pollution health risk estimates in copollutant time-series models.

PubMed

Dionisio, Kathie L; Chang, Howard H; Baxter, Lisa K

2016-11-25

Exposure measurement error in copollutant epidemiologic models has the potential to introduce bias in relative risk (RR) estimates. A simulation study was conducted using empirical data to quantify the impact of correlated measurement errors in time-series analyses of air pollution and health. ZIP-code level estimates of exposure for six pollutants (CO, NO x , EC, PM 2.5 , SO 4 , O 3 ) from 1999 to 2002 in the Atlanta metropolitan area were used to calculate spatial, population (i.e. ambient versus personal), and total exposure measurement error. Empirically determined covariance of pollutant concentration pairs and the associated measurement errors were used to simulate true exposure (exposure without error) from observed exposure. Daily emergency department visits for respiratory diseases were simulated using a Poisson time-series model with a main pollutant RR = 1.05 per interquartile range, and a null association for the copollutant (RR = 1). Monte Carlo experiments were used to evaluate the impacts of correlated exposure errors of different copollutant pairs. Substantial attenuation of RRs due to exposure error was evident in nearly all copollutant pairs studied, ranging from 10 to 40% attenuation for spatial error, 3-85% for population error, and 31-85% for total error. When CO, NO x or EC is the main pollutant, we demonstrated the possibility of false positives, specifically identifying significant, positive associations for copollutants based on the estimated type I error rate. The impact of exposure error must be considered when interpreting results of copollutant epidemiologic models, due to the possibility of attenuation of main pollutant RRs and the increased probability of false positives when measurement error is present.

Spatial-temporal-covariance-based modeling, analysis, and simulation of aero-optics wavefront aberrations.

PubMed

Vogel, Curtis R; Tyler, Glenn A; Wittich, Donald J

2014-07-01

We introduce a framework for modeling, analysis, and simulation of aero-optics wavefront aberrations that is based on spatial-temporal covariance matrices extracted from wavefront sensor measurements. Within this framework, we present a quasi-homogeneous structure function to analyze nonhomogeneous, mildly anisotropic spatial random processes, and we use this structure function to show that phase aberrations arising in aero-optics are, for an important range of operating parameters, locally Kolmogorov. This strongly suggests that the d5/3 power law for adaptive optics (AO) deformable mirror fitting error, where d denotes actuator separation, holds for certain important aero-optics scenarios. This framework also allows us to compute bounds on AO servo lag error and predictive control error. In addition, it provides us with the means to accurately simulate AO systems for the mitigation of aero-effects, and it may provide insight into underlying physical processes associated with turbulent flow. The techniques introduced here are demonstrated using data obtained from the Airborne Aero-Optics Laboratory.

Attitudes toward Face-to-Face and Online Counseling: Roles of Self-Concealment, Openness to Experience, Loss of Face, Stigma, and Disclosure Expectations among Korean College Students

ERIC Educational Resources Information Center

Bathje, Geoff J.; Kim, Eunha; Rau, Ellen; Bassiouny, Muhammad Adam; Kim, Taehoon

2014-01-01

This study examined attitudes toward face-to-face (f2f) and online counseling among 228 Korean college students. In addition, it tested a hypothesized model proposing that general propensities (i.e., self-concealment, openness to experience, and loss of face) would influence counseling-specific expectations (i.e., self-stigma and disclosure…

Protection of Public Figures. Symposium Proceedings, May 16-18, 1972

DTIC Science & Technology

1972-01-01

192 EXPLOSIVE TRACE VAPOR DETECTION, Maryland D. Keyrw, USAMERDC.. 194 ATOMIC AND MOLECULAR DETECTION...subject through a doorway, a hallway, a portal, a fence, and thus subject him to co- vert surveillance for weapons or explosives concealed on his person...who has weapons or conceal- ed explosives on his person. So insofar as 4ERDC is concerned, the two broad scenarios that we will be talking about are

Preventing Shoulder-Surfing Attack with the Concept of Concealing the Password Objects' Information

PubMed Central

Ho, Peng Foong; Kam, Yvonne Hwei-Syn; Wee, Mee Chin

2014-01-01

Traditionally, picture-based password systems employ password objects (pictures/icons/symbols) as input during an authentication session, thus making them vulnerable to “shoulder-surfing” attack because the visual interface by function is easily observed by others. Recent software-based approaches attempt to minimize this threat by requiring users to enter their passwords indirectly by performing certain mental tasks to derive the indirect password, thus concealing the user's actual password. However, weaknesses in the positioning of distracter and password objects introduce usability and security issues. In this paper, a new method, which conceals information about the password objects as much as possible, is proposed. Besides concealing the password objects and the number of password objects, the proposed method allows both password and distracter objects to be used as the challenge set's input. The correctly entered password appears to be random and can only be derived with the knowledge of the full set of password objects. Therefore, it would be difficult for a shoulder-surfing adversary to identify the user's actual password. Simulation results indicate that the correct input object and its location are random for each challenge set, thus preventing frequency of occurrence analysis attack. User study results show that the proposed method is able to prevent shoulder-surfing attack. PMID:24991649

The effects of sweep numbers per average and protocol type on the accuracy of the p300-based concealed information test.

PubMed

Dietrich, Ariana B; Hu, Xiaoqing; Rosenfeld, J Peter

2014-03-01

In the first of two experiments, we compared the accuracy of the P300 concealed information test protocol as a function of numbers of trials experienced by subjects and ERP averages analyzed by investigators. Contrary to Farwell et al. (Cogn Neurodyn 6(2):115-154, 2012), we found no evidence that 100 trial based averages are more accurate than 66 or 33 trial based averages (all numbers led to accuracies of 84-94 %). There was actually a trend favoring the lowest trial numbers. The second study compared numbers of irrelevant stimuli recalled and recognized in the 3-stimulus protocol versus the complex trial protocol (Rosenfeld in Memory detection: theory and application of the concealed information test, Cambridge University Press, New York, pp 63-89, 2011). Again, in contrast to expectations from Farwell et al. (Cogn Neurodyn 6(2):115-154, 2012), there were no differences between protocols, although there were more irrelevant stimuli recognized than recalled, and irrelevant 4-digit number group stimuli were neither recalled nor recognized as well as irrelevant city name stimuli. We therefore conclude that stimulus processing in the P300-based complex trial protocol-with no more than 33 sweep averages-is adequate to allow accurate detection of concealed information.

Assessment of Registration Information on Methodological Design of Acupuncture RCTs: A Review of 453 Registration Records Retrieved from WHO International Clinical Trials Registry Platform

PubMed Central

Gu, Jing; Wang, Qi; Wang, Xiaogang; Li, Hailong; Gu, Mei; Ming, Haixia; Dong, Xiaoli; Yang, Kehu; Wu, Hongyan

2014-01-01

Background. This review provides the first methodological information assessment of protocol of acupuncture RCTs registered in WHO International Clinical Trials Registry Platform (ICTRP). Methods. All records of acupuncture RCTs registered in the ICTRP have been collected. The methodological design assessment involved whether the randomization methods, allocation concealment, and blinding were adequate or not based on the information of registration records (protocols of acupuncture RCTs). Results. A total of 453 records, found in 11 registries, were examined. Methodological details were insufficient in registration records; there were 76.4%, 89.0%, and 21.4% records that did not provide information on randomization methods, allocation concealment, and blinding respectively. The proportions of adequate randomization methods, allocation concealment, and blinding were only 107 (23.6%), 48 (10.6%), and 210 (46.4%), respectively. The methodological design improved year by year, especially after 2007. Additionally, methodology of RCTs with ethics approval was clearly superior to those without ethics approval and different among registries. Conclusions. The overall methodological design based on registration records of acupuncture RCTs is not very well but improved year by year. The insufficient information on randomization methods, allocation concealment, and blinding maybe due to the relevant description is not taken seriously in acupuncture RCTs' registration. PMID:24688591

Assessment of Registration Information on Methodological Design of Acupuncture RCTs: A Review of 453 Registration Records Retrieved from WHO International Clinical Trials Registry Platform.

PubMed

Gu, Jing; Wang, Qi; Wang, Xiaogang; Li, Hailong; Gu, Mei; Ming, Haixia; Dong, Xiaoli; Yang, Kehu; Wu, Hongyan

2014-01-01

Background. This review provides the first methodological information assessment of protocol of acupuncture RCTs registered in WHO International Clinical Trials Registry Platform (ICTRP). Methods. All records of acupuncture RCTs registered in the ICTRP have been collected. The methodological design assessment involved whether the randomization methods, allocation concealment, and blinding were adequate or not based on the information of registration records (protocols of acupuncture RCTs). Results. A total of 453 records, found in 11 registries, were examined. Methodological details were insufficient in registration records; there were 76.4%, 89.0%, and 21.4% records that did not provide information on randomization methods, allocation concealment, and blinding respectively. The proportions of adequate randomization methods, allocation concealment, and blinding were only 107 (23.6%), 48 (10.6%), and 210 (46.4%), respectively. The methodological design improved year by year, especially after 2007. Additionally, methodology of RCTs with ethics approval was clearly superior to those without ethics approval and different among registries. Conclusions. The overall methodological design based on registration records of acupuncture RCTs is not very well but improved year by year. The insufficient information on randomization methods, allocation concealment, and blinding maybe due to the relevant description is not taken seriously in acupuncture RCTs' registration.

Feasibility, diagnostic validity and limits of postmortem evaluation of a newborn infant following an extremely prolonged freezing interval: a thanatological case study.

PubMed

Krajčovič, Jozef; Janík, Martin; Novomeský, František; Straka, Lubomír; Hejna, Petr

2014-11-01

In forensic assessment, denial and concealment of pregnancy has wide-ranging implications including criminal abortions, extramural deliveries, concealment of birth, newborn infant abandonment or even neonaticide. Clarification of whether a newborn was born alive is the most important factor when evaluating an abandoned neonate or concealment of birth. Other points that need to be addressed are determination of viability and maturity of the newborn infant, and the identity of the mother. A prolonged postmortem interval following illegal disposal of a dead body often leads to advanced decomposition, making postmortem elucidation difficult. We report an exceptionally uncommon autopsy case of a well-preserved female newborn, which was accidentally found after eight years in a home freezer. Despite the prolonged postmortem interval, tissue preservation was sufficient for a meaningful autopsy including a comprehensive histopathological study. The purpose of the present investigations was to expand our understanding of thanatological processes, as well as detectability of particular histological findings on the remains of a newborn after extremely prolonged storage in an artificially frozen environment. In addition, this article discusses forensically important issues regarding concealment of newborn infant under specific conditions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Concealed neuroanatomy in Michelangelo's Separation of Light From Darkness in the Sistine Chapel.

PubMed

Suk, Ian; Tamargo, Rafael J

2010-05-01

Michelangelo Buonarroti (1475-1564) was a master anatomist as well as an artistic genius. He dissected cadavers numerous times and developed a profound understanding of human anatomy. From 1508 to 1512, Michelangelo painted the ceiling of the Sistine Chapel in Rome. His Sistine Chapel frescoes are considered one of the monumental achievements of Renaissance art. In the winter of 1511, Michelangelo entered the final stages of the Sistine Chapel project and painted 4 frescoes along the longitudinal apex of the vault, which completed a series of 9 central panels depicting scenes from the Book of Genesis. It is reported that Michelangelo concealed an image of the brain in the first of these last 4 panels, namely, the Creation of Adam. Here we present evidence that he concealed another neuronanatomic structure in the final panel of this series, the Separation of Light From Darkness, specifically a ventral view of the brainstem. The Separation of Light From Darkness is an important panel in the Sistine Chapel iconography because it depicts the beginning of Creation and is located directly above the altar. We propose that Michelangelo, a deeply religious man and an accomplished anatomist, intended to enhance the meaning of this iconographically critical panel and possibly document his anatomic accomplishments by concealing this sophisticated neuroanatomic rendering within the image of God.

Technology addiction's contribution to mental wellbeing: The positive effect of online social capital.

PubMed

Magsamen-Conrad, Kate; Billotte-Verhoff, China; Greene, Kathryn

2014-11-01

This research examines the effect of online social capital and Internet use on the normally negative effects of technology addiction, especially for individuals prone to self-concealment. Self-concealment is a personality trait that describes individuals who are more likely to withhold personal and private information, inhibiting catharsis and wellbeing. Addiction, in any context, is also typically associated with negative outcomes. However, we investigate the hypothesis that communication technology addiction may positively affect wellbeing for self-concealing individuals when online interaction is positive, builds relationships, or fosters a sense of community. Within these parameters, increased communication through mediated channels (and even addiction) may reverse the otherwise negative effects of self-concealment on wellbeing. Overall, the proposed model offers qualified support for the continued analysis of mediated communication as a potential source for improving the wellbeing for particular individuals. This study is important because we know that healthy communication in relationships, including disclosure, is important to wellbeing. This study recognizes that not all people are comfortable communicating in face-to-face settings. Our findings offer evidence that the presence of computers in human behaviors (e.g., mediated channels of communication and NCTs) enables some individuals to communicate and fos ter beneficial interpersonal relationships, and improve their wellbeing.

Technology addiction's contribution to mental wellbeing: The positive effect of online social capital

PubMed Central

Magsamen-Conrad, Kate; Billotte-Verhoff, China; Greene, Kathryn

2014-01-01

This research examines the effect of online social capital and Internet use on the normally negative effects of technology addiction, especially for individuals prone to self-concealment. Self-concealment is a personality trait that describes individuals who are more likely to withhold personal and private information, inhibiting catharsis and wellbeing. Addiction, in any context, is also typically associated with negative outcomes. However, we investigate the hypothesis that communication technology addiction may positively affect wellbeing for self-concealing individuals when online interaction is positive, builds relationships, or fosters a sense of community. Within these parameters, increased communication through mediated channels (and even addiction) may reverse the otherwise negative effects of self-concealment on wellbeing. Overall, the proposed model offers qualified support for the continued analysis of mediated communication as a potential source for improving the wellbeing for particular individuals. This study is important because we know that healthy communication in relationships, including disclosure, is important to wellbeing. This study recognizes that not all people are comfortable communicating in face-to-face settings. Our findings offer evidence that the presence of computers in human behaviors (e.g., mediated channels of communication and NCTs) enables some individuals to communicate and fos ter beneficial interpersonal relationships, and improve their wellbeing. PMID:25568591

Multiple window spatial registration error of a gamma camera: 133Ba point source as a replacement of the NEMA procedure.

PubMed

Bergmann, Helmar; Minear, Gregory; Raith, Maria; Schaffarich, Peter M

2008-12-09

The accuracy of multiple window spatial resolution characterises the performance of a gamma camera for dual isotope imaging. In the present study we investigate an alternative method to the standard NEMA procedure for measuring this performance parameter. A long-lived 133Ba point source with gamma energies close to 67Ga and a single bore lead collimator were used to measure the multiple window spatial registration error. Calculation of the positions of the point source in the images used the NEMA algorithm. The results were validated against the values obtained by the standard NEMA procedure which uses a liquid 67Ga source with collimation. Of the source-collimator configurations under investigation an optimum collimator geometry, consisting of a 5 mm thick lead disk with a diameter of 46 mm and a 5 mm central bore, was selected. The multiple window spatial registration errors obtained by the 133Ba method showed excellent reproducibility (standard deviation < 0.07 mm). The values were compared with the results from the NEMA procedure obtained at the same locations and showed small differences with a correlation coefficient of 0.51 (p < 0.05). In addition, the 133Ba point source method proved to be much easier to use. A Bland-Altman analysis showed that the 133Ba and the 67Ga Method can be used interchangeably. The 133Ba point source method measures the multiple window spatial registration error with essentially the same accuracy as the NEMA-recommended procedure, but is easier and safer to use and has the potential to replace the current standard procedure.

Field evaluation of the error arising from inadequate time averaging in the standard use of depth-integrating suspended-sediment samplers

USGS Publications Warehouse

Topping, David J.; Rubin, David M.; Wright, Scott A.; Melis, Theodore S.

2011-01-01

Several common methods for measuring suspended-sediment concentration in rivers in the United States use depth-integrating samplers to collect a velocity-weighted suspended-sediment sample in a subsample of a river cross section. Because depth-integrating samplers are always moving through the water column as they collect a sample, and can collect only a limited volume of water and suspended sediment, they collect only minimally time-averaged data. Four sources of error exist in the field use of these samplers: (1) bed contamination, (2) pressure-driven inrush, (3) inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration, and (4) inadequate time averaging. The first two of these errors arise from misuse of suspended-sediment samplers, and the third has been the subject of previous study using data collected in the sand-bedded Middle Loup River in Nebraska. Of these four sources of error, the least understood source of error arises from the fact that depth-integrating samplers collect only minimally time-averaged data. To evaluate this fourth source of error, we collected suspended-sediment data between 1995 and 2007 at four sites on the Colorado River in Utah and Arizona, using a P-61 suspended-sediment sampler deployed in both point- and one-way depth-integrating modes, and D-96-A1 and D-77 bag-type depth-integrating suspended-sediment samplers. These data indicate that the minimal duration of time averaging during standard field operation of depth-integrating samplers leads to an error that is comparable in magnitude to that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. This random error arising from inadequate time averaging is positively correlated with grain size and does not largely depend on flow conditions or, for a given size class of suspended sediment, on elevation above the bed. Averaging over time scales >1 minute is the likely minimum duration required to result in substantial decreases in this error. During standard two-way depth integration, a depth-integrating suspended-sediment sampler collects a sample of the water-sediment mixture during two transits at each vertical in a cross section: one transit while moving from the water surface to the bed, and another transit while moving from the bed to the water surface. As the number of transits is doubled at an individual vertical, this error is reduced by ~30 percent in each size class of suspended sediment. For a given size class of suspended sediment, the error arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration depends only on the number of verticals collected, whereas the error arising from inadequate time averaging depends on both the number of verticals collected and the number of transits collected at each vertical. Summing these two errors in quadrature yields a total uncertainty in an equal-discharge-increment (EDI) or equal-width-increment (EWI) measurement of the time-averaged velocity-weighted suspended-sediment concentration in a river cross section (exclusive of any laboratory-processing errors). By virtue of how the number of verticals and transits influences the two individual errors within this total uncertainty, the error arising from inadequate time averaging slightly dominates that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. Adding verticals to an EDI or EWI measurement is slightly more effective in reducing the total uncertainty than adding transits only at each vertical, because a new vertical contributes both temporal and spatial information. However, because collection of depth-integrated samples at more transits at each vertical is generally easier and faster than at more verticals, addition of a combination of verticals and transits is likely a more practical approach to reducing the total uncertainty in most field situatio

Patient safety culture in China: a case study in an outpatient setting in Beijing

PubMed Central

Liu, Chaojie; Liu, Weiwei; Wang, Yuanyuan; Zhang, Zhihong; Wang, Peng

2014-01-01

Objectives To investigate the patient safety culture in an outpatient setting in Beijing and explore the meaning and implications of the safety culture from the perspective of health workers and patients. Methods A mixed methods approach involving a questionnaire survey and in-depth interviews was adopted. Among the 410 invited staff members, 318 completed the Hospital Survey of Patient Safety Culture (HSOPC). Patient safety culture was described using 12 subscale scores. Inter-subscale correlation analysis, ANOVA and stepwise multivariate regression analyses were performed to identify the determinants of the patient safety culture scores. Interviewees included 22 patients selected through opportunity sampling and 27 staff members selected through purposive sampling. The interview data were analysed thematically. Results The survey respondents perceived high levels of unsafe care but had personally reported few events. Lack of ‘communication openness’ was identified as a major safety culture problem, and a perception of ‘penalty’ was the greatest barrier to the encouragement of error reporting. Cohesive ‘teamwork within units’, while found to be an area of strength, conversely served as a protective and defensive mechanism for medical practice. Low levels of trust between providers and consumers and lack of management support constituted an obstacle to building a positive patient safety culture. Conclusions This study in China demonstrates that a punitive approach to error is still widespread despite increasing awareness of unsafe care, and managers have been slow in acknowledging the importance of building a positive patient safety culture. Strong ‘teamwork within units’, a common area of strength, could fuel the concealment of errors. PMID:24351971

Standoff passive video imaging at 350 GHz with 251 superconducting detectors

NASA Astrophysics Data System (ADS)

Becker, Daniel; Gentry, Cale; Smirnov, Ilya; Ade, Peter; Beall, James; Cho, Hsiao-Mei; Dicker, Simon; Duncan, William; Halpern, Mark; Hilton, Gene; Irwin, Kent; Li, Dale; Paulter, Nicholas; Reintsema, Carl; Schwall, Robert; Tucker, Carole

2014-06-01

Millimeter wavelength radiation holds promise for detection of security threats at a distance, including suicide bomb belts and maritime threats in poor weather. The high sensitivity of superconducting Transition Edge Sensor (TES) detectors makes them ideal for passive imaging of thermal signals at these wavelengths. We have built a 350 GHz video-rate imaging system using a large-format array of feedhorn-coupled TES bolometers. The system operates at a standoff distance of 16m to 28m with a spatial resolution of 1:4 cm (at 17m). It currently contains one 251-detector subarray, and will be expanded to contain four subarrays for a total of 1004 detectors. The system has been used to take video images which reveal the presence of weapons concealed beneath a shirt in an indoor setting. We present a summary of this work.

Decomposition of Sources of Errors in Seasonal Streamflow Forecasts in a Rainfall-Runoff Dominated Basin

NASA Astrophysics Data System (ADS)

Sinha, T.; Arumugam, S.

2012-12-01

Seasonal streamflow forecasts contingent on climate forecasts can be effectively utilized in updating water management plans and optimize generation of hydroelectric power. Streamflow in the rainfall-runoff dominated basins critically depend on forecasted precipitation in contrast to snow dominated basins, where initial hydrological conditions (IHCs) are more important. Since precipitation forecasts from Atmosphere-Ocean-General Circulation Models are available at coarse scale (~2.8° by 2.8°), spatial and temporal downscaling of such forecasts are required to implement land surface models, which typically runs on finer spatial and temporal scales. Consequently, multiple sources are introduced at various stages in predicting seasonal streamflow. Therefore, in this study, we addresses the following science questions: 1) How do we attribute the errors in monthly streamflow forecasts to various sources - (i) model errors, (ii) spatio-temporal downscaling, (iii) imprecise initial conditions, iv) no forecasts, and (iv) imprecise forecasts? and 2) How does monthly streamflow forecast errors propagate with different lead time over various seasons? In this study, the Variable Infiltration Capacity (VIC) model is calibrated over Apalachicola River at Chattahoochee, FL in the southeastern US and implemented with observed 1/8° daily forcings to estimate reference streamflow during 1981 to 2010. The VIC model is then forced with different schemes under updated IHCs prior to forecasting period to estimate relative mean square errors due to: a) temporally disaggregation, b) spatial downscaling, c) Reverse Ensemble Streamflow Prediction (imprecise IHCs), d) ESP (no forecasts), and e) ECHAM4.5 precipitation forecasts. Finally, error propagation under different schemes are analyzed with different lead time over different seasons.

Evaluation of snow cover and snow depth on the Qinghai-Tibetan Plateau derived from passive microwave remote sensing

NASA Astrophysics Data System (ADS)

Dai, Liyun; Che, Tao; Ding, Yongjian; Hao, Xiaohua

2017-08-01

Snow cover on the Qinghai-Tibetan Plateau (QTP) plays a significant role in the global climate system and is an important water resource for rivers in the high-elevation region of Asia. At present, passive microwave (PMW) remote sensing data are the only efficient way to monitor temporal and spatial variations in snow depth at large scale. However, existing snow depth products show the largest uncertainties across the QTP. In this study, MODIS fractional snow cover product, point, line and intense sampling data are synthesized to evaluate the accuracy of snow cover and snow depth derived from PMW remote sensing data and to analyze the possible causes of uncertainties. The results show that the accuracy of snow cover extents varies spatially and depends on the fraction of snow cover. Based on the assumption that grids with MODIS snow cover fraction > 10 % are regarded as snow cover, the overall accuracy in snow cover is 66.7 %, overestimation error is 56.1 %, underestimation error is 21.1 %, commission error is 27.6 % and omission error is 47.4 %. The commission and overestimation errors of snow cover primarily occur in the northwest and southeast areas with low ground temperature. Omission error primarily occurs in cold desert areas with shallow snow, and underestimation error mainly occurs in glacier and lake areas. With the increase of snow cover fraction, the overestimation error decreases and the omission error increases. A comparison between snow depths measured in field experiments, measured at meteorological stations and estimated across the QTP shows that agreement between observation and retrieval improves with an increasing number of observation points in a PMW grid. The misclassification and errors between observed and retrieved snow depth are associated with the relatively coarse resolution of PMW remote sensing, ground temperature, snow characteristics and topography. To accurately understand the variation in snow depth across the QTP, new algorithms should be developed to retrieve snow depth with higher spatial resolution and should consider the variation in brightness temperatures at different frequencies emitted from ground with changing ground features.

Transferring Error Characteristics of Satellite Rainfall Data from Ground Validation (gauged) into Non-ground Validation (ungauged)

NASA Astrophysics Data System (ADS)

Tang, L.; Hossain, F.

2009-12-01

Understanding the error characteristics of satellite rainfall data at different spatial/temporal scales is critical, especially when the scheduled Global Precipitation Mission (GPM) plans to provide High Resolution Precipitation Products (HRPPs) at global scales. Satellite rainfall data contain errors which need ground validation (GV) data for characterization, while satellite rainfall data will be most useful in the regions that are lacking in GV. Therefore, a critical step is to develop a spatial interpolation scheme for transferring the error characteristics of satellite rainfall data from GV regions to Non-GV regions. As a prelude to GPM, The TRMM Multi-satellite Precipitation Analysis (TMPA) products of 3B41RT and 3B42RT (Huffman et al., 2007) over the US spanning a record of 6 years are used as a representative example of satellite rainfall data. Next Generation Radar (NEXRAD) Stage IV rainfall data are used as the reference for GV data. Initial work by the authors (Tang et al., 2009, GRL) has shown promise in transferring error from GV to Non-GV regions, based on a six-year climatologic average of satellite rainfall data assuming only 50% of GV coverage. However, this transfer of error characteristics needs to be investigated for a range of GV data coverage. In addition, it is also important to investigate if proxy-GV data from an accurate space-borne sensor, such as the TRMM PR (or the GPM DPR), can be leveraged for the transfer of error at sparsely gauged regions. The specific question we ask in this study is, “what is the minimum coverage of GV data required for error transfer scheme to be implemented at acceptable accuracy in hydrological relevant scale?” Three geostatistical interpolation methods are compared: ordinary kriging, indicator kriging and disjunctive kriging. Various error metrics are assessed for transfer such as, Probability of Detection for rain and no rain, False Alarm Ratio, Frequency Bias, Critical Success Index, RMSE etc. Understanding the proper space-time scales at which these metrics can be reasonably transferred is also explored in this study. Keyword: Satellite rainfall, error transfer, spatial interpolation, kriging methods.

Comparison of different interpolation methods for spatial distribution of soil organic carbon and some soil properties in the Black Sea backward region of Turkey

NASA Astrophysics Data System (ADS)

Göl, Ceyhun; Bulut, Sinan; Bolat, Ferhat

2017-10-01

The purpose of this research is to compare the spatial variability of soil organic carbon (SOC) in four adjacent land uses including the cultivated area, the grassland area, the plantation area and the natural forest area in the semi - arid region of Black Sea backward region of Turkey. Some of the soil properties, including total nitrogen, SOC, soil organic matter, and bulk density were measured on a grid with a 50 m sampling distance on the top soil (0-15 cm depth). Accordingly, a total of 120 samples were taken from the four adjacent land uses. Data was analyzed using geostatistical methods. The methods used were: Block kriging (BK), co - kriging (CK) with organic matter, total nitrogen and bulk density as auxiliary variables and inverse distance weighting (IDW) methods with the power of 1, 2 and 4. The methods were compared using a performance criteria that included root mean square error (RMSE), mean absolute error (MAE) and the coefficient of correlation (r). The one - way ANOVA test showed that differences between the natural (0.6653 ± 0.2901) - plantation forest (0.7109 ± 0.2729) areas and the grassland (1.3964 ± 0.6828) - cultivated areas (1.5851 ± 0.5541) were statistically significant at 0.05 level (F = 28.462). The best model for describing spatially variation of SOC was CK with the lowest error criteria (RMSE = 0.3342, MAE = 0.2292) and the highest coefficient of correlation (r = 0.84). The spatial structure of SOC could be well described by the spherical model. The nugget effect indicated that SOC was moderately dependent on the study area. The error distributions of the model showed that the improved model was unbiased in predicting the spatial distribution of SOC. This study's results revealed that an explanatory variable linked SOC increased success of spatial interpolation methods. In subsequent studies, this case should be taken into account for reaching more accurate outputs.

Evaluation of seasonal and spatial variations of lumped water balance model sensitivity to precipitation data errors

NASA Astrophysics Data System (ADS)

Xu, Chong-yu; Tunemar, Liselotte; Chen, Yongqin David; Singh, V. P.

2006-06-01

Sensitivity of hydrological models to input data errors have been reported in the literature for particular models on a single or a few catchments. A more important issue, i.e. how model's response to input data error changes as the catchment conditions change has not been addressed previously. This study investigates the seasonal and spatial effects of precipitation data errors on the performance of conceptual hydrological models. For this study, a monthly conceptual water balance model, NOPEX-6, was applied to 26 catchments in the Mälaren basin in Central Sweden. Both systematic and random errors were considered. For the systematic errors, 5-15% of mean monthly precipitation values were added to the original precipitation to form the corrupted input scenarios. Random values were generated by Monte Carlo simulation and were assumed to be (1) independent between months, and (2) distributed according to a Gaussian law of zero mean and constant standard deviation that were taken as 5, 10, 15, 20, and 25% of the mean monthly standard deviation of precipitation. The results show that the response of the model parameters and model performance depends, among others, on the type of the error, the magnitude of the error, physical characteristics of the catchment, and the season of the year. In particular, the model appears less sensitive to the random error than to the systematic error. The catchments with smaller values of runoff coefficients were more influenced by input data errors than were the catchments with higher values. Dry months were more sensitive to precipitation errors than were wet months. Recalibration of the model with erroneous data compensated in part for the data errors by altering the model parameters.

Spatial perseveration error by alpacas (Vicugna pacos) in an A-not-B detour task.

PubMed

Abramson, José Z; Paulina Soto, D; Beatriz Zapata, S; Lloreda, María Victoria Hernández

2018-05-01

Spatial perseveration has been documented for domestic animals such as mules, donkeys, horses and dogs. However, evidence for this spatial cognition behavior among other domestic species is scarce. Alpacas have been domesticated for at least 7000 years yet their cognitive ability has not been officially reported. The present article used an A-not-B detour task to study the spatial problem-solving abilities of alpacas (Vicugna pacos) and to identify the perseveration errors, which refers to a tendency to maintain a learned route, despite having another available path. The study tested 51 alpacas, which had to pass through a gap at one end of a barrier in order to reach a reward. After one, two, three or four repeats (A trials), the gap was moved to the opposite end of the barrier (B trials). In contrast to what has been found in other domestic animals tested with the same task, the present study did not find clear evidence of spatial perseveration. Individuals' performance in the subsequent B trials, following the change of gap location, suggests no error persistence in alpacas. Results suggest that alpacas are more flexible than other domestic animals tested with this same task, which has important implications in planning proper training for experimental designs or productive purposes. These results could contribute toward enhancing alpacas' welfare and our understanding of their cognitive abilities.

Sampling design optimization for spatial functions

USGS Publications Warehouse

Olea, R.A.

1984-01-01

A new procedure is presented for minimizing the sampling requirements necessary to estimate a mappable spatial function at a specified level of accuracy. The technique is based on universal kriging, an estimation method within the theory of regionalized variables. Neither actual implementation of the sampling nor universal kriging estimations are necessary to make an optimal design. The average standard error and maximum standard error of estimation over the sampling domain are used as global indices of sampling efficiency. The procedure optimally selects those parameters controlling the magnitude of the indices, including the density and spatial pattern of the sample elements and the number of nearest sample elements used in the estimation. As an illustration, the network of observation wells used to monitor the water table in the Equus Beds of Kansas is analyzed and an improved sampling pattern suggested. This example demonstrates the practical utility of the procedure, which can be applied equally well to other spatial sampling problems, as the procedure is not limited by the nature of the spatial function. ?? 1984 Plenum Publishing Corporation.

Performance of GPS-devices for environmental exposure assessment.

PubMed

Beekhuizen, Johan; Kromhout, Hans; Huss, Anke; Vermeulen, Roel

2013-01-01

Integration of individual time-location patterns with spatially resolved exposure maps enables a more accurate estimation of personal exposures to environmental pollutants than using estimates at fixed locations. Current global positioning system (GPS) devices can be used to track an individual's location. However, information on GPS-performance in environmental exposure assessment is largely missing. We therefore performed two studies. First, a commute-study, where the commute of 12 individuals was tracked twice, testing GPS-performance for five transport modes and two wearing modes. Second, an urban-tracking study, where one individual was tracked repeatedly through different areas, focused on the effect of building obstruction on GPS-performance. The median error from the true path for walking was 3.7 m, biking 2.9 m, train 4.8 m, bus 4.9 m, and car 3.3 m. Errors were larger in a high-rise commercial area (median error=7.1 m) compared with a low-rise residential area (median error=2.2 m). Thus, GPS-performance largely depends on the transport mode and urban built-up. Although ~85% of all errors were <10 m, almost 1% of the errors were >50 m. Modern GPS-devices are useful tools for environmental exposure assessment, but large GPS-errors might affect estimates of exposures with high spatial variability.

Increasing accuracy of dispersal kernels in grid-based population models

USGS Publications Warehouse

Slone, D.H.

2011-01-01

Dispersal kernels in grid-based population models specify the proportion, distance and direction of movements within the model landscape. Spatial errors in dispersal kernels can have large compounding effects on model accuracy. Circular Gaussian and Laplacian dispersal kernels at a range of spatial resolutions were investigated, and methods for minimizing errors caused by the discretizing process were explored. Kernels of progressively smaller sizes relative to the landscape grid size were calculated using cell-integration and cell-center methods. These kernels were convolved repeatedly, and the final distribution was compared with a reference analytical solution. For large Gaussian kernels (σ > 10 cells), the total kernel error was <10 &sup-11; compared to analytical results. Using an invasion model that tracked the time a population took to reach a defined goal, the discrete model results were comparable to the analytical reference. With Gaussian kernels that had σ ≤ 0.12 using the cell integration method, or σ ≤ 0.22 using the cell center method, the kernel error was greater than 10%, which resulted in invasion times that were orders of magnitude different than theoretical results. A goal-seeking routine was developed to adjust the kernels to minimize overall error. With this, corrections for small kernels were found that decreased overall kernel error to <10-11 and invasion time error to <5%.

Error Types and Error Positions in Neglect Dyslexia: Comparative Analyses in Neglect Patients and Healthy Controls

ERIC Educational Resources Information Center

Weinzierl, Christiane; Kerkhoff, Georg; van Eimeren, Lucia; Keller, Ingo; Stenneken, Prisca

2012-01-01

Unilateral spatial neglect frequently involves a lateralised reading disorder, neglect dyslexia (ND). Reading of single words in ND is characterised by left-sided omissions and substitutions of letters. However, it is unclear whether the distribution of error types and positions within a word shows a unique pattern of ND when directly compared to…

The dependence of crowding on flanker complexity and target-flanker similarity

PubMed Central

Bernard, Jean-Baptiste; Chung, Susana T.L.

2013-01-01

We examined the effects of the spatial complexity of flankers and target-flanker similarity on the performance of identifying crowded letters. On each trial, observers identified the middle character of random strings of three characters (“trigrams”) briefly presented at 10° below fixation. We tested the 26 lowercase letters of the Times-Roman and Courier fonts, a set of 79 characters (letters and non-letters) of the Times-Roman font, and the uppercase letters of two highly complex ornamental fonts, Edwardian and Aristocrat. Spatial complexity of characters was quantified by the length of the morphological skeleton of each character, and target-flanker similarity was defined based on a psychometric similarity matrix. Our results showed that (1) letter identification error rate increases with flanker complexity up to a certain value, beyond which error rate becomes independent of flanker complexity; (2) the increase of error rate is slower for high-complexity target letters; (3) error rate increases with target-flanker similarity; and (4) mislocation error rate increases with target-flanker similarity. These findings, combined with the current understanding of the faulty feature integration account of crowding, provide some constraints of how the feature integration process could cause perceptual errors. PMID:21730225

Multiscale measurement error models for aggregated small area health data.

PubMed

Aregay, Mehreteab; Lawson, Andrew B; Faes, Christel; Kirby, Russell S; Carroll, Rachel; Watjou, Kevin

2016-08-01

Spatial data are often aggregated from a finer (smaller) to a coarser (larger) geographical level. The process of data aggregation induces a scaling effect which smoothes the variation in the data. To address the scaling problem, multiscale models that link the convolution models at different scale levels via the shared random effect have been proposed. One of the main goals in aggregated health data is to investigate the relationship between predictors and an outcome at different geographical levels. In this paper, we extend multiscale models to examine whether a predictor effect at a finer level hold true at a coarser level. To adjust for predictor uncertainty due to aggregation, we applied measurement error models in the framework of multiscale approach. To assess the benefit of using multiscale measurement error models, we compare the performance of multiscale models with and without measurement error in both real and simulated data. We found that ignoring the measurement error in multiscale models underestimates the regression coefficient, while it overestimates the variance of the spatially structured random effect. On the other hand, accounting for the measurement error in multiscale models provides a better model fit and unbiased parameter estimates. © The Author(s) 2016.

Medical makeup for concealing facial scars.

PubMed

Mee, Donna; Wong, Brian J F

2012-10-01

Surgical, laser, and pharmacological therapies are all used to correct scars and surgical incisions, though have limits with respect to how well facial skin can be restored or enhanced. The use of cosmetics has long been a relevant adjunct to all scar treatment modalities. In recent years, technical advancements in the chemistry and composition of cosmetic products have provided the patient with a broader range of products to employ for concealing scars. This review will provide an overview of contemporary methods for concealing facial scars, birthmarks, and pigmentary changes without the use of traditional/dated, heavy appearing camouflage products. Additionally, general guidelines and information will be provided with respect to identifying competent makeup artists for care of the medical patient. The article by no means is meant to be a tutorial, but rather serves as a starting point in this allied field of medicine. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Passive millimeter-wave concealed weapon detection

NASA Astrophysics Data System (ADS)

Sinclair, Gordon N.; Anderton, Rupert N.; Appleby, Roger

2001-02-01

A method of detecting weapons concealed under clothing using passive millimeter wave imaging is described. The optical properties of clothing are discussed and examples given of the spectral reflectivity and transmission. The transmission tends to be constant from 60 to 150 GHz above which it decreases for some clothing materials. The transmission of a cotton T-shirt is typically 95% and of a leather jacket up to 85% at lower frequencies. A model is presented for calculating the contrast of a metallic concealed weapon when hidden under clothing and it indicates contrasts as large as 200 K can be realized outdoors. The advantages of real time over static frame imagery are discussed. It is concluded that real time imagery offers considerable advantages as weapons can be very varied in size, position and orientation and movement offers vital clues to the human observer which aid the recognition process.

High-resolution wavefront control of high-power laser systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brase, J; Brown, C; Carrano, C

1999-07-08

Nearly every new large-scale laser system application at LLNL has requirements for beam control which exceed the current level of available technology. For applications such as inertial confinement fusion, laser isotope separation, laser machining, and laser the ability to transport significant power to a target while maintaining good beam quality is critical. There are many ways that laser wavefront quality can be degraded. Thermal effects due to the interaction of high-power laser or pump light with the internal optical components or with the ambient gas are common causes of wavefront degradation. For many years, adaptive optics based on thing deformablemore » glass mirrors with piezoelectric or electrostrictive actuators have be used to remove the low-order wavefront errors from high-power laser systems. These adaptive optics systems have successfully improved laser beam quality, but have also generally revealed additional high-spatial-frequency errors, both because the low-order errors have been reduced and because deformable mirrors have often introduced some high-spatial-frequency components due to manufacturing errors. Many current and emerging laser applications fall into the high-resolution category where there is an increased need for the correction of high spatial frequency aberrations which requires correctors with thousands of degrees of freedom. The largest Deformable Mirrors currently available have less than one thousand degrees of freedom at a cost of approximately $1M. A deformable mirror capable of meeting these high spatial resolution requirements would be cost prohibitive. Therefore a new approach using a different wavefront control technology is needed. One new wavefront control approach is the use of liquid-crystal (LC) spatial light modulator (SLM) technology for the controlling the phase of linearly polarized light. Current LC SLM technology provides high-spatial-resolution wavefront control, with hundreds of thousands of degrees of freedom, more than two orders of magnitude greater than the best Deformable Mirrors currently made. Even with the increased spatial resolution, the cost of these devices is nearly two orders of magnitude less than the cost of the largest deformable mirror.« less

The problem of latent attentional capture: Easy visual search conceals capture by task-irrelevant abrupt onsets.

PubMed

Gaspelin, Nicholas; Ruthruff, Eric; Lien, Mei-Ching

2016-08-01

Researchers are sharply divided regarding whether irrelevant abrupt onsets capture spatial attention. Numerous studies report that they do and a roughly equal number report that they do not. This puzzle has inspired numerous attempts at reconciliation, none gaining general acceptance. The authors propose that abrupt onsets routinely capture attention, but the size of observed capture effects depends critically on how long attention dwells on distractor items which, in turn, depends critically on search difficulty. In a series of spatial cuing experiments, the authors show that irrelevant abrupt onsets produce robust capture effects when visual search is difficult, but not when search is easy. Critically, this effect occurs even when search difficulty varies randomly across trials, preventing any strategic adjustments of the attentional set that could modulate probability of capture by the onset cue. The authors argue that easy visual search provides an insensitive test for stimulus-driven capture by abrupt onsets: even though onsets truly capture attention, the effects of capture can be latent. This observation helps to explain previous failures to find capture by onsets, nearly all of which used an easy visual search. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Improvement of individual camouflage through background choice in ground-nesting birds.

PubMed

Stevens, Martin; Troscianko, Jolyon; Wilson-Aggarwal, Jared K; Spottiswoode, Claire N

2017-09-01

Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal's own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest that individuals from several animal taxa could select backgrounds or positions to improve concealment. Here, we test whether individual wild animals choose backgrounds in complex environments, and whether this improves camouflage against predator vision. We studied nest site selection by nine species of ground-nesting birds (nightjars, plovers and coursers) in Zambia, and used image analysis and vision modeling to quantify egg and plumage camouflage to predator vision. Individual birds chose backgrounds that enhanced their camouflage, being better matched to their chosen backgrounds than to other potential backgrounds with respect to multiple aspects of camouflage. This occurred at all three spatial scales tested (a few cm and five meters from the nest, and compared to other sites chosen by conspecifics), and was the case for the eggs of all bird groups studied, and for adult nightjar plumage. Thus, individual wild animals improve their camouflage through active background choice, with choices highly refined across multiple spatial scales.

Improvement of individual camouflage through background choice in ground-nesting birds

PubMed Central

Stevens, Martin; Troscianko, Jolyon; Wilson-Aggarwal, Jared K.; Spottiswoode, Claire N.

2017-01-01

Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal's own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest that individuals from several animal taxa could select backgrounds or positions to improve concealment. Here, we test whether individual wild animals choose backgrounds in complex environments, and whether this improves camouflage against predator vision. We studied nest site selection by nine species of ground-nesting birds (nightjars, plovers and coursers) in Zambia, and used image analysis and vision modeling to quantify egg and plumage camouflage to predator vision. Individual birds chose backgrounds that enhanced their camouflage, being better matched to their chosen backgrounds than to other potential backgrounds with respect to multiple aspects of camouflage. This occurred at all three spatial scales tested (a few cm and five meters from the nest, and compared to other sites chosen by conspecifics), and was the case for the eggs of all bird groups studied, and for adult nightjar plumage. Thus, individual wild animals improve their camouflage through active background choice, with choices highly refined across multiple spatial scales. PMID:28890937

The Problem of Latent Attentional Capture: Easy Visual Search Conceals Capture by Task-Irrelevant Abrupt Onsets

PubMed Central

Gaspelin, Nicholas; Ruthruff, Eric; Lien, Mei-Ching

2016-01-01

Researchers are sharply divided regarding whether irrelevant abrupt onsets capture spatial attention. Numerous studies report that they do and a roughly equal number report that they do not. This puzzle has inspired numerous attempts at reconciliation, none gaining general acceptance. We propose that abrupt onsets routinely capture attention, but the size of observed capture effects depends critically on how long attention dwells on distractor items which, in turn, depends critically on search difficulty. In a series of spatial cuing experiments, we show that irrelevant abrupt onsets produce robust capture effects when visual search is difficult, but not when search is easy. Critically, this effect occurs even when search difficulty varies randomly across trials, preventing any strategic adjustments of the attentional set that could modulate probability of capture by the onset cue. We argue that easy visual search provides an insensitive test for stimulus-driven capture by abrupt onsets: even though onsets truly capture attention, the effects of capture can be latent. This observation helps to explain previous failures to find capture by onsets, nearly all of which employed an easy visual search. PMID:26854530

Terahertz parametric sources and imaging applications

NASA Astrophysics Data System (ADS)

Yamashita, M.; Ogawa, Y.; Otani, C.; Kawase, K.

2005-12-01

We have studied the generation of terahertz (THz) waves by optical parametric processes based on laser light scattering from the polariton mode of nonlinear crystals. Using parametric oscillation of LiNbO 3 or MgO-doped LiNbO 3 crystal pumped by a nano-second Q-switched Nd:YAG laser, we have realized a widely tunable coherent THz-wave sources with a simple configuration. We report the detailed characteristics of the oscillation and the radiation including tunability, spatial and temporal coherency, uni directivity, and efficiency. A Fourier transform limited THz-wave spectrum narrowing was achieved by introducing the injection seeding method. Further, we have developed a spectroscopic THz imaging system using a TPO, which allows detection and identification of drugs concealed in envelopes, by introducing the component spatial pattern analysis. Several images of the envelope are recorded at different THz frequencies and then processed. The final result is an image that reveals what substances are present in the envelope, in what quantity, and how they are distributed across the envelope area. The example presented here shows the identification of three drugs, two of which illegal, while one is an over-the-counter drug.

Terahertz parametric sources and imaging applications

NASA Astrophysics Data System (ADS)

Kawase, Kodo; Ogawa, Yuichi; Minamide, Hiroaki; Ito, Hiromasa

2005-07-01

We have studied the generation of terahertz (THz) waves by optical parametric processes based on laser light scattering from the polariton mode of nonlinear crystals. Using parametric oscillation of LiNbO3 or MgO-doped LiNbO3 crystal pumped by a nano-second Q-switched Nd:YAG laser, we have realized a widely tunable coherent THz-wave source with a simple configuration. We report the detailed characteristics of the oscillation and the radiation including tunability, spatial and temporal coherency, uni-directivity, and efficiency. A Fourier transform limited THz-wave spectrum narrowing was achieved by introducing the injection seeding method. Further, we have developed a spectroscopic THz imaging system using a THz-wave parametric oscillator, which allows detection and identification of drugs concealed in envelopes, by introducing the component spatial pattern analysis. Several images of the envelope are recorded at different THz frequencies and then processed. The final result is an image that reveals what substances are present in the envelope, in what quantity, and how they are distributed across the envelope area. The example presented here shows the identification of three drugs, two of which are illegal, while one is an over-the-counter drug.

Assessing representation errors of IAGOS CO2, CO and CH4 profile observations: the impact of spatial variations in near-field emissions

NASA Astrophysics Data System (ADS)

Boschetti, Fabio; Thouret, Valerie; Nedelec, Philippe; Chen, Huilin; Gerbig, Christoph

2015-04-01

Airborne platforms have their main strength in the ability of collecting mixing ratio and meteorological data at different heights across a vertical profile, allowing an insight in the internal structure of the atmosphere. However, rental airborne platforms are usually expensive, limiting the number of flights that can be afforded and hence on the amount of data that can be collected. To avoid this disadvantage, the MOZAIC/IAGOS (Measurements of Ozone and water vapor by Airbus In-service airCraft/In-service Aircraft for a Global Observing System) program makes use of commercial airliners, providing data on a regular basis. It is therefore considered an important tool in atmospheric investigations. However, due to the nature of said platforms, MOZAIC/IAGOS's profiles are located near international airports, which are usually significant emission sources, and are in most cases close to major urban settlements, characterized by higher anthropogenic emissions compared to rural areas. When running transport models at finite resolution, these local emissions can heavily affect measurements resulting in biases in model/observation mismatch. Model/observation mismatch can include different aspects in both horizontal and vertical direction, for example spatial and temporal resolution of the modeled fluxes, or poorly represented convective transport or turbulent mixing in the boundary layer. In the framework of the IGAS (IAGOS for GMES Atmospheric Service) project, whose aim is to improve connections between data collected by MOZAIC/IAGOS and Copernicus Atmospheric Service, the present study is focused on the effect of the spatial resolution of emission fluxes, referred to here as representation error. To investigate this, the Lagrangian transport model STILT (Stochastic Time Inverted Lagrangian Transport) was coupled with EDGAR (Emission Database for Global Atmospheric Research) version-4.3 emission inventory at European regional scale. EDGAR's simulated fluxes for CO, CO2 and CH4 with a spatial resolution of 10x10 km for the time frame 2006-2011 was be aggregated into coarser and coarser grid cells in order to evaluate the representation error at different spatial scales. The dependence of representation error from wind direction and month of the year was evaluated for different location in the European domain, for both random and bias component. The representation error was then validated against the model-data mismatch derived from the comparison of MACC (Monitoring Atmospheric Composition and Climate) reanalysis with IAGOS observations for CO to investigate its suitability for modeling applications. We found that the random and bias components of the representation error show a similar pattern dependent on wind direction. In addition, we found a clear linear relationship between the representation error and the model-data mismatch for both (random and bias) components, indicating that about 50% of the model-data mismatch is related to the representation error. This suggests that the representation error derived using STILT provides useful information for better understanding causes for model-data mismatch.

Why do we miss rare targets? Exploring the boundaries of the low prevalence effect

PubMed Central

Rich, Anina N.; Kunar, Melina A.; Van Wert, Michael J.; Hidalgo-Sotelo, Barbara; Horowitz, Todd S.; Wolfe, Jeremy M.

2011-01-01

Observers tend to miss a disproportionate number of targets in visual search tasks with rare targets. This ‘prevalence effect’ may have practical significance since many screening tasks (e.g., airport security, medical screening) are low prevalence searches. It may also shed light on the rules used to terminate search when a target is not found. Here, we use perceptually simple stimuli to explore the sources of this effect. Experiment 1 shows a prevalence effect in inefficient spatial configuration search. Experiment 2 demonstrates this effect occurs even in a highly efficient feature search. However, the two prevalence effects differ. In spatial configuration search, misses seem to result from ending the search prematurely, while in feature search, they seem due to response errors. In Experiment 3, a minimum delay before response eliminated the prevalence effect for feature but not spatial configuration search. In Experiment 4, a target was present on each trial in either two (2AFC) or four (4AFC) orientations. With only two response alternatives, low prevalence produced elevated errors. Providing four response alternatives eliminated this effect. Low target prevalence puts searchers under pressure that tends to increase miss errors. We conclude that the specific source of those errors depends on the nature of the search. PMID:19146299

Triple collocation-based estimation of spatially correlated observation error covariance in remote sensing soil moisture data assimilation

NASA Astrophysics Data System (ADS)

Wu, Kai; Shu, Hong; Nie, Lei; Jiao, Zhenhang

2018-01-01

Spatially correlated errors are typically ignored in data assimilation, thus degenerating the observation error covariance R to a diagonal matrix. We argue that a nondiagonal R carries more observation information making assimilation results more accurate. A method, denoted TC_Cov, was proposed for soil moisture data assimilation to estimate spatially correlated observation error covariance based on triple collocation (TC). Assimilation experiments were carried out to test the performance of TC_Cov. AMSR-E soil moisture was assimilated with a diagonal R matrix computed using the TC and assimilated using a nondiagonal R matrix, as estimated by proposed TC_Cov. The ensemble Kalman filter was considered as the assimilation method. Our assimilation results were validated against climate change initiative data and ground-based soil moisture measurements using the Pearson correlation coefficient and unbiased root mean square difference metrics. These experiments confirmed that deterioration of diagonal R assimilation results occurred when model simulation is more accurate than observation data. Furthermore, nondiagonal R achieved higher correlation coefficient and lower ubRMSD values over diagonal R in experiments and demonstrated the effectiveness of TC_Cov to estimate richly structuralized R in data assimilation. In sum, compared with diagonal R, nondiagonal R may relieve the detrimental effects of assimilation when simulated model results outperform observation data.

Deterministic ion beam material adding technology for high-precision optical surfaces.

PubMed

Liao, Wenlin; Dai, Yifan; Xie, Xuhui; Zhou, Lin

2013-02-20

Although ion beam figuring (IBF) provides a highly deterministic method for the precision figuring of optical components, several problems still need to be addressed, such as the limited correcting capability for mid-to-high spatial frequency surface errors and low machining efficiency for pit defects on surfaces. We propose a figuring method named deterministic ion beam material adding (IBA) technology to solve those problems in IBF. The current deterministic optical figuring mechanism, which is dedicated to removing local protuberances on optical surfaces, is enriched and developed by the IBA technology. Compared with IBF, this method can realize the uniform convergence of surface errors, where the particle transferring effect generated in the IBA process can effectively correct the mid-to-high spatial frequency errors. In addition, IBA can rapidly correct the pit defects on the surface and greatly improve the machining efficiency of the figuring process. The verification experiments are accomplished on our experimental installation to validate the feasibility of the IBA method. First, a fused silica sample with a rectangular pit defect is figured by using IBA. Through two iterations within only 47.5 min, this highly steep pit is effectively corrected, and the surface error is improved from the original 24.69 nm root mean square (RMS) to the final 3.68 nm RMS. Then another experiment is carried out to demonstrate the correcting capability of IBA for mid-to-high spatial frequency surface errors, and the final results indicate that the surface accuracy and surface quality can be simultaneously improved.

Mapping Patterns and Trends in the Spatial Availability of Alcohol Using Low-Level Geographic Data: A Case Study in England 2003-2013.

PubMed

Angus, Colin; Holmes, John; Maheswaran, Ravi; Green, Mark A; Meier, Petra; Brennan, Alan

2017-04-12

Much literature examines the relationship between the spatial availability of alcohol and alcohol-related harm. This study aims to address an important gap in this evidence by using detailed outlet data to examine recent temporal trends in the sociodemographic distribution of spatial availability for different types of alcohol outlet in England. Descriptive analysis of measures of alcohol outlet density and proximity using extremely high resolution market research data stratified by outlet type and quintiles of area-level deprivation from 2003, 2007, 2010 and 2013 was undertaken and hierarchical linear growth models fitted to explore the significance of socioeconomic differences. We find that overall availability of alcohol changed very little from 2003 to 2013 (density +1.6%), but this conceals conflicting trends by outlet type and area-level deprivation. Mean on-trade density has decreased substantially (-2.2 outlets within 1 km (Inter-Quartile Range (IQR) -3-0), although access to restaurants has increased (+1.0 outlets (IQR 0-1)), while off-trade access has risen substantially (+2.4 outlets (IQR 0-3)). Availability is highest in the most deprived areas ( p < 0.0001) although these areas have also seen the greatest falls in on-trade outlet availability ( p < 0.0001). This study underlines the importance of using detailed, low-level geographic data to understand patterns and trends in the spatial availability of alcohol. There are significant variations in these trends by outlet type and deprivation level which may have important implications for health inequalities and public health policy.

Mapping Patterns and Trends in the Spatial Availability of Alcohol Using Low-Level Geographic Data: A Case Study in England 2003–2013

PubMed Central

Angus, Colin; Holmes, John; Maheswaran, Ravi; Green, Mark A.; Meier, Petra; Brennan, Alan

2017-01-01

Much literature examines the relationship between the spatial availability of alcohol and alcohol-related harm. This study aims to address an important gap in this evidence by using detailed outlet data to examine recent temporal trends in the sociodemographic distribution of spatial availability for different types of alcohol outlet in England. Descriptive analysis of measures of alcohol outlet density and proximity using extremely high resolution market research data stratified by outlet type and quintiles of area-level deprivation from 2003, 2007, 2010 and 2013 was undertaken and hierarchical linear growth models fitted to explore the significance of socioeconomic differences. We find that overall availability of alcohol changed very little from 2003 to 2013 (density +1.6%), but this conceals conflicting trends by outlet type and area-level deprivation. Mean on-trade density has decreased substantially (−2.2 outlets within 1 km (Inter-Quartile Range (IQR) −3–0), although access to restaurants has increased (+1.0 outlets (IQR 0–1)), while off-trade access has risen substantially (+2.4 outlets (IQR 0–3)). Availability is highest in the most deprived areas (p < 0.0001) although these areas have also seen the greatest falls in on-trade outlet availability (p < 0.0001). This study underlines the importance of using detailed, low-level geographic data to understand patterns and trends in the spatial availability of alcohol. There are significant variations in these trends by outlet type and deprivation level which may have important implications for health inequalities and public health policy. PMID:28417941

Clothing adjustments for concealed soft body armor during moderate physical exertion.

PubMed

Ryan, Greg A; Bishop, Stacy H; Herron, Robert L; Katica, Charles P; Elbon, Bre'anna L; Bosak, Andrew M; Bishop, Phillip

2015-01-01

Previous research has studied the impact of Level II concealed soft body armor (SBA) on the augmentation of heat storage in a hot environment simulating a typical summer day in the southeastern United States (wet bulb globe temperature [WBGT] = 30°C) and noted a significant difference between macro- and micro-WBGTs. The purpose of this study was to characterize the microclimate (micro-WBGT) under a concealed Level II SBA during 60 min of moderately intense work at two separate macro-WBGTs (26°C and 30°C), and to establish WBGT corrections to allow prediction of heat strain in an individual wearing a concealed Level II SBA. A single trial was performed with nine volunteers (27 ± 4 years) outfitted with a simulated standard law enforcement uniform and a traditional concealed Level II SBA, in a moderately warm environment (WBGT = 26°C). Each participant performed cycles of 12 min of walking (1.25 L · min(-1)) and 3 min of arm curls (14.3 kg, 0.6 L · min(-1)) with a 5 min rest after every other cycle, for a total of 60 minutes. This trial was compared to an identical previously completed 60-min work bout at 30°C. A two-way repeated measures ANOVA with Post hoc Bonferroni and paired samples t-test analysis was conducted. A greater difference between macro- micro-WBGTs existed at 26°C compared to the 30°C macro-WBGT. Under these conditions, a moderate work in Level II SBA requires a WBGT correction of 8.9°C and 6.2°C at macro-WBGTs of 26°C and 30°C, respectively. A modified simple linear regression prediction model was established for mean Micro-WBGT for each macro-WBGTs after the plateau point at the 30 min mark. The derivation regressions at 26°C (R(2) = 0.99), and 30°C (R(2) = 0.99) indicate that micro-WBGT could be predicted for each 15 minutes time at both macro-WBGTs tested for individuals doing moderate intensity (300 Kcals · hr(-1)) work wearing concealed Level II SBA.

Results on the spatial resolution of repetitive transcranial magnetic stimulation for cortical language mapping during object naming in healthy subjects.

PubMed

Sollmann, Nico; Hauck, Theresa; Tussis, Lorena; Ille, Sebastian; Maurer, Stefanie; Boeckh-Behrens, Tobias; Ringel, Florian; Meyer, Bernhard; Krieg, Sandro M

2016-10-24

The spatial resolution of repetitive navigated transcranial magnetic stimulation (rTMS) for language mapping is largely unknown. Thus, to determine a minimum spatial resolution of rTMS for language mapping, we evaluated the mapping sessions derived from 19 healthy volunteers for cortical hotspots of no-response errors. Then, the distances between hotspots (stimulation points with a high error rate) and adjacent mapping points (stimulation points with low error rates) were evaluated. Mean distance values of 13.8 ± 6.4 mm (from hotspots to ventral points, range 0.7-30.7 mm), 10.8 ± 4.8 mm (from hotspots to dorsal points, range 2.0-26.5 mm), 16.6 ± 4.8 mm (from hotspots to apical points, range 0.9-27.5 mm), and 13.8 ± 4.3 mm (from hotspots to caudal points, range 2.0-24.2 mm) were measured. According to the results, the minimum spatial resolution of rTMS should principally allow for the identification of a particular gyrus, and according to the literature, it is in good accordance with the spatial resolution of direct cortical stimulation (DCS). Since measurement was performed between hotspots and adjacent mapping points and not on a finer-grained basis, we only refer to a minimum spatial resolution. Furthermore, refinement of our results within the scope of a prospective study combining rTMS and DCS for resolution measurement during language mapping should be the next step.

Asymmetric generalization in adaptation to target displacement errors in humans and in a neural network model.

PubMed

Westendorff, Stephanie; Kuang, Shenbing; Taghizadeh, Bahareh; Donchin, Opher; Gail, Alexander

2015-04-01

Different error signals can induce sensorimotor adaptation during visually guided reaching, possibly evoking different neural adaptation mechanisms. Here we investigate reach adaptation induced by visual target errors without perturbing the actual or sensed hand position. We analyzed the spatial generalization of adaptation to target error to compare it with other known generalization patterns and simulated our results with a neural network model trained to minimize target error independent of prediction errors. Subjects reached to different peripheral visual targets and had to adapt to a sudden fixed-amplitude displacement ("jump") consistently occurring for only one of the reach targets. Subjects simultaneously had to perform contralateral unperturbed saccades, which rendered the reach target jump unnoticeable. As a result, subjects adapted by gradually decreasing reach errors and showed negative aftereffects for the perturbed reach target. Reach errors generalized to unperturbed targets according to a translational rather than rotational generalization pattern, but locally, not globally. More importantly, reach errors generalized asymmetrically with a skewed generalization function in the direction of the target jump. Our neural network model reproduced the skewed generalization after adaptation to target jump without having been explicitly trained to produce a specific generalization pattern. Our combined psychophysical and simulation results suggest that target jump adaptation in reaching can be explained by gradual updating of spatial motor goal representations in sensorimotor association networks, independent of learning induced by a prediction-error about the hand position. The simulations make testable predictions about the underlying changes in the tuning of sensorimotor neurons during target jump adaptation. Copyright © 2015 the American Physiological Society.

Asymmetric generalization in adaptation to target displacement errors in humans and in a neural network model

PubMed Central

Westendorff, Stephanie; Kuang, Shenbing; Taghizadeh, Bahareh; Donchin, Opher

2015-01-01

Different error signals can induce sensorimotor adaptation during visually guided reaching, possibly evoking different neural adaptation mechanisms. Here we investigate reach adaptation induced by visual target errors without perturbing the actual or sensed hand position. We analyzed the spatial generalization of adaptation to target error to compare it with other known generalization patterns and simulated our results with a neural network model trained to minimize target error independent of prediction errors. Subjects reached to different peripheral visual targets and had to adapt to a sudden fixed-amplitude displacement (“jump”) consistently occurring for only one of the reach targets. Subjects simultaneously had to perform contralateral unperturbed saccades, which rendered the reach target jump unnoticeable. As a result, subjects adapted by gradually decreasing reach errors and showed negative aftereffects for the perturbed reach target. Reach errors generalized to unperturbed targets according to a translational rather than rotational generalization pattern, but locally, not globally. More importantly, reach errors generalized asymmetrically with a skewed generalization function in the direction of the target jump. Our neural network model reproduced the skewed generalization after adaptation to target jump without having been explicitly trained to produce a specific generalization pattern. Our combined psychophysical and simulation results suggest that target jump adaptation in reaching can be explained by gradual updating of spatial motor goal representations in sensorimotor association networks, independent of learning induced by a prediction-error about the hand position. The simulations make testable predictions about the underlying changes in the tuning of sensorimotor neurons during target jump adaptation. PMID:25609106

Importance of spatial autocorrelation in modeling bird distributions at a continental scale

USGS Publications Warehouse

Bahn, V.; O'Connor, R.J.; Krohn, W.B.

2006-01-01

Spatial autocorrelation in species' distributions has been recognized as inflating the probability of a type I error in hypotheses tests, causing biases in variable selection, and violating the assumption of independence of error terms in models such as correlation or regression. However, it remains unclear whether these problems occur at all spatial resolutions and extents, and under which conditions spatially explicit modeling techniques are superior. Our goal was to determine whether spatial models were superior at large extents and across many different species. In addition, we investigated the importance of purely spatial effects in distribution patterns relative to the variation that could be explained through environmental conditions. We studied distribution patterns of 108 bird species in the conterminous United States using ten years of data from the Breeding Bird Survey. We compared the performance of spatially explicit regression models with non-spatial regression models using Akaike's information criterion. In addition, we partitioned the variance in species distributions into an environmental, a pure spatial and a shared component. The spatially-explicit conditional autoregressive regression models strongly outperformed the ordinary least squares regression models. In addition, partialling out the spatial component underlying the species' distributions showed that an average of 17% of the explained variation could be attributed to purely spatial effects independent of the spatial autocorrelation induced by the underlying environmental variables. We concluded that location in the range and neighborhood play an important role in the distribution of species. Spatially explicit models are expected to yield better predictions especially for mobile species such as birds, even in coarse-grained models with a large extent. ?? Ecography.

Optical Oversampled Analog-to-Digital Conversion

DTIC Science & Technology

1992-06-29

hologram weights and interconnects in the digital image halftoning configuration. First, no temporal error diffusion occurs in the digital image... halftoning error diffusion ar- chitecture as demonstrated by Equation (6.1). Equation (6.2) ensures that the hologram weights sum to one so that the exact...optimum halftone image should be faster. Similarly, decreased convergence time suggests that an error diffusion filter with larger spatial dimensions

Sinusoidal Siemens star spatial frequency response measurement errors due to misidentified target centers

DOE PAGES

Birch, Gabriel Carisle; Griffin, John Clark

2015-07-23

Numerous methods are available to measure the spatial frequency response (SFR) of an optical system. A recent change to the ISO 12233 photography resolution standard includes a sinusoidal Siemens star test target. We take the sinusoidal Siemens star proposed by the ISO 12233 standard, measure system SFR, and perform an analysis of errors induced by incorrectly identifying the center of a test target. We show a closed-form solution for the radial profile intensity measurement given an incorrectly determined center and describe how this error reduces the measured SFR of the system. As a result, using the closed-form solution, we proposemore » a two-step process by which test target centers are corrected and the measured SFR is restored to the nominal, correctly centered values.« less

The effect of the dynamic wet troposphere on radio interferometric measurements

NASA Technical Reports Server (NTRS)

Treuhaft, R. N.; Lanyi, G. E.

1987-01-01

A statistical model of water vapor fluctuations is used to describe the effect of the dynamic wet troposphere on radio interferometric measurements. It is assumed that the spatial structure of refractivity is approximated by Kolmogorov turbulence theory, and that the temporal fluctuations are caused by spatial patterns moved over a site by the wind, and these assumptions are examined for the VLBI delay and delay rate observables. The results suggest that the delay rate measurement error is usually dominated by water vapor fluctuations, and water vapor induced VLBI parameter errors and correlations are determined as a function of the delay observable errors. A method is proposed for including the water vapor fluctuations in the parameter estimation method to obtain improved parameter estimates and parameter covariances.

Contribution of stimulus attributes to errors in duration and distance judgments--a developmental study.

PubMed

Matsuda, F; Lan, W C; Tanimura, R

1999-02-01

In Matsuda's 1996 study, 4- to 11-yr.-old children (N = 133) watched two cars running on two parallel tracks on a CRT display and judged whether their durations and distances were equal and, if not, which was larger. In the present paper, the relative contributions of the four critical stimulus attributes (whether temporal starting points, temporal stopping points, spatial starting points, and spatial stopping points were the same or different between two cars) to the production of errors were quantitatively estimated based on the data for rates of errors obtained by Matsuda. The present analyses made it possible not only to understand numerically the findings about qualitative characteristics of the critical attributes described by Matsuda, but also to add more detailed findings about them.

Beam Width Robustness of a 670 GHz Imaging Radar

NASA Technical Reports Server (NTRS)

Cooper, K. B.; Llombart, N.; Dengler, R. J.; Siegel, P. H.

2009-01-01

Detection of a replica bomb belt concealed on a mannequin at 4 m standoff range is achieved using a 670 GHz imaging radar. At a somewhat larger standoff range of 4.6 m, the radar's beam width increases substantially, but the through-shirt image quality remains good. This suggests that a relatively modest increase in aperture size over the current design will be sufficient to detect person-borne concealed weapons at ranges exceeding 25 meters.

Understanding Where Americas Public Discussion Takes Place In Todays Society: Case Studies of Concealed Weapons Carry Reform

DTIC Science & Technology

2016-06-01

media sources on the public discourse. This research compares and contrasts the roles and importance of traditional and social media in the public...alternative media , social media 15. NUMBER OF PAGES 73 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY...importance of traditional and social media in the public sphere today, as evidenced by the coverage of concealed-carry laws and related stories. The

Parasystole due to re-entry as the possible mechanism of ventricular parasystole with second-degree entrance block.

PubMed

Kinoshita, Shinji; Katoh, Takakazu; Yoshida, Hiroshi

2010-05-01

In 1974, Kinoshita reported a case of 'irregular parasystole' due to type I second-degree entrance block. Since then, many cases of such 'irregular' parasystole have been reported by us. To explain the mechanism of 'irregular' parasystole, two theories have been suggested, namely, 'electrotonic modulation' by Jalife and Moe, and 'type I second-degree entrance block' by us. On the contrary, in 1960, Kinoshita et al. reported a case of concealed bigeminy for the first time. The electrocardiographic findings in concealed bigeminy have suggested that there are dual re-entrant pathways with markedly long effective refractory periods in the re-entrant pathway. We have suggested that parasystole may be caused by re-entry in such re-entrant pathways. In this article, attempts are made to explain the mechanism of all the electrocardiographic findings in our cases of parasystole by 'parasystole due to re-entry'. Using 24 studies on parasystole and 21 studies on concealed extrasystoles that we have reported over 50 years, as well as three exemplary cases in this article, attempts are made to explain all electrocardiographic findings in parasystole by 'parasystole due to re-entry'. The electrocardiographic findings in our previous clinical cases of parasystole and concealed extrasystoles, as well as exemplary cases and diagrams in the present article, strongly suggest 'parasystole due to re-entry' as the mechanism of ventricular parasystole with second-degree entrance block.

[Concealed penis and its surgical correction: a report of 63 cases].

PubMed

Cheng, Fan; Zhang, Xiaobin; Liu, Xiuheng; Zhou, Jiangqiao; Xia, Yue; Ge, Minghuan

2004-02-01

To evaluate the basic principles of surgical correction of concealed penis. From Jan. 1999 to Dec. 2002, 63 cases of concealed penis, aged from 1 year and 6 months to 19 years with a mean age of 7 years and 2 months, were corrected with two different approaches: 37 cases of group A with obesity were corrected by anchoring micrus tissue onto the pubis at the base of the penis, and 26 cases of group B by fixing the subcutateous tissues at both sides of the penile shaft to the deep tunica albuginea at the penile root. Then prepuce plasty was carried out. Six-month postoperative follow-up found adequate exposure of the penis in all of group A, prepuce oedema in 7 cases, abdomen fat liquidization in 3 cases, unsatisfactory recovery of incision hollow in 3 cases and patchy numbness of the glans in 1 case. The 25 cases of group B had satisfactory exposure of the penis, with no obvious prepuce oedema, 1 case with retraction of the penis 7 days after operation. Various surgical procedures could be adopted for concealed penis, and the key to the satisfactory appearance is the restoration of penile tunicae and the fixation at the base of the penis. Further study is needed to determine the natural history of these disorders as well as which conditions and what age will benefit most from surgical intervention.

Micro-topography mediates interactions between corals, algae, and herbivorous fishes on coral reefs

NASA Astrophysics Data System (ADS)

Brandl, S. J.; Hoey, A. S.; Bellwood, D. R.

2014-06-01

Processes occurring during the early life stages of corals are important for the replenishment of coral assemblages and the resilience of coral reefs. However, the factors influencing early life stages of corals are not well understood, and the role of micro-topographic complexity for habitat associations of juvenile corals is largely unexplored. This study investigated the microhabitat distribution patterns of early life stages of corals and a potential macroalgal competitor ( Turbinaria ornata) across two reef zones (reef crest and outer reef flat) on Lizard Island, Great Barrier Reef. In both reef zones, both corals and T. ornata were significantly more abundant in concealed microhabitats than in semi-concealed or open microhabitats (GLMM: P < 0.001). The prevalence of juvenile corals and T. ornata within concealed environments suggests that they might be effective refuges from grazing by herbivorous fishes. The density of juvenile corals was positively related, and density of T. ornata negatively related to the abundance of two groups of herbivorous fishes, pairing rabbitfishes, and surgeonfishes in the genus Zebrasoma (BEST ENV-BIO: r s = 0.72, P < 0.01), which feed in concealed microhabitats. This correlative evidence suggests that crevices may be important for early life stages of both coral and macroalgae, and that a specific suite of crevice-feeding fishes may influence benthic community dynamics in these microhabitats.

Standoff concealed weapon detection using a 350-GHz radar imaging system

NASA Astrophysics Data System (ADS)

Sheen, David M.; Hall, Thomas E.; Severtsen, Ronald H.; McMakin, Douglas L.; Hatchell, Brian K.; Valdez, Patrick L. J.

2010-04-01

The sub-millimeter (sub-mm) wave frequency band from 300 - 1000 GHz is currently being developed for standoff concealed weapon detection imaging applications. This frequency band is of interest due to the unique combination of high resolution and clothing penetration. The Pacific Northwest National Laboratory (PNNL) is currently developing a 350 GHz, active, wideband, three-dimensional, radar imaging system to evaluate the feasibility of active sub-mm imaging for standoff detection. Standoff concealed weapon and explosive detection is a pressing national and international need for both civilian and military security, as it may allow screening at safer distances than portal screening techniques. PNNL has developed a prototype active wideband 350 GHz radar imaging system based on a wideband, heterodyne, frequency-multiplier-based transceiver system coupled to a quasi-optical focusing system and high-speed rotating conical scanner. This prototype system operates at ranges up to 10+ meters, and can acquire an image in 10 - 20 seconds, which is fast enough to scan cooperative personnel for concealed weapons. The wideband operation of this system provides accurate ranging information, and the images obtained are fully three-dimensional. During the past year, several improvements to the system have been designed and implemented, including increased imaging speed using improved balancing techniques, wider bandwidth, and improved image processing techniques. In this paper, the imaging system is described in detail and numerous imaging results are presented.

Enhancing the use of Argos satellite data for home range and long distance migration studies of marine animals.

PubMed

Hoenner, Xavier; Whiting, Scott D; Hindell, Mark A; McMahon, Clive R

2012-01-01

Accurately quantifying animals' spatial utilisation is critical for conservation, but has long remained an elusive goal due to technological impediments. The Argos telemetry system has been extensively used to remotely track marine animals, however location estimates are characterised by substantial spatial error. State-space models (SSM) constitute a robust statistical approach to refine Argos tracking data by accounting for observation errors and stochasticity in animal movement. Despite their wide use in ecology, few studies have thoroughly quantified the error associated with SSM predicted locations and no research has assessed their validity for describing animal movement behaviour. We compared home ranges and migratory pathways of seven hawksbill sea turtles (Eretmochelys imbricata) estimated from (a) highly accurate Fastloc GPS data and (b) locations computed using common Argos data analytical approaches. Argos 68(th) percentile error was <1 km for LC 1, 2, and 3 while markedly less accurate (>4 km) for LC ≤ 0. Argos error structure was highly longitudinally skewed and was, for all LC, adequately modelled by a Student's t distribution. Both habitat use and migration routes were best recreated using SSM locations post-processed by re-adding good Argos positions (LC 1, 2 and 3) and filtering terrestrial points (mean distance to migratory tracks ± SD = 2.2 ± 2.4 km; mean home range overlap and error ratio = 92.2% and 285.6 respectively). This parsimonious and objective statistical procedure however still markedly overestimated true home range sizes, especially for animals exhibiting restricted movements. Post-processing SSM locations nonetheless constitutes the best analytical technique for remotely sensed Argos tracking data and we therefore recommend using this approach to rework historical Argos datasets for better estimation of animal spatial utilisation for research and evidence-based conservation purposes.

Characterization of errors in a coupled snow hydrology-microwave emission model

USGS Publications Warehouse

Andreadis, K.M.; Liang, D.; Tsang, L.; Lettenmaier, D.P.; Josberger, E.G.

2008-01-01

Traditional approaches to the direct estimation of snow properties from passive microwave remote sensing have been plagued by limitations such as the tendency of estimates to saturate for moderately deep snowpacks and the effects of mixed land cover within remotely sensed pixels. An alternative approach is to assimilate satellite microwave emission observations directly, which requires embedding an accurate microwave emissions model into a hydrologic prediction scheme, as well as quantitative information of model and observation errors. In this study a coupled snow hydrology [Variable Infiltration Capacity (VIC)] and microwave emission [Dense Media Radiative Transfer (DMRT)] model are evaluated using multiscale brightness temperature (TB) measurements from the Cold Land Processes Experiment (CLPX). The ability of VIC to reproduce snowpack properties is shown with the use of snow pit measurements, while TB model predictions are evaluated through comparison with Ground-Based Microwave Radiometer (GBMR), air-craft [Polarimetric Scanning Radiometer (PSR)], and satellite [Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)] TB measurements. Limitations of the model at the point scale were not as evident when comparing areal estimates. The coupled model was able to reproduce the TB spatial patterns observed by PSR in two of three sites. However, this was mostly due to the presence of relatively dense forest cover. An interesting result occurs when examining the spatial scaling behavior of the higher-resolution errors; the satellite-scale error is well approximated by the mode of the (spatial) histogram of errors at the smaller scale. In addition, TB prediction errors were almost invariant when aggregated to the satellite scale, while forest-cover fractions greater than 30% had a significant effect on TB predictions. ?? 2008 American Meteorological Society.

Improving the Non-Hydrostatic Numerical Dust Model by Integrating Soil Moisture and Greenness Vegetation Fraction Data with Different Spatiotemporal Resolutions.

PubMed

Yu, Manzhu; Yang, Chaowei

2016-01-01

Dust storms are devastating natural disasters that cost billions of dollars and many human lives every year. Using the Non-Hydrostatic Mesoscale Dust Model (NMM-dust), this research studies how different spatiotemporal resolutions of two input parameters (soil moisture and greenness vegetation fraction) impact the sensitivity and accuracy of a dust model. Experiments are conducted by simulating dust concentration during July 1-7, 2014, for the target area covering part of Arizona and California (31, 37, -118, -112), with a resolution of ~ 3 km. Using ground-based and satellite observations, this research validates the temporal evolution and spatial distribution of dust storm output from the NMM-dust, and quantifies model error using measurements of four evaluation metrics (mean bias error, root mean square error, correlation coefficient and fractional gross error). Results showed that the default configuration of NMM-dust (with a low spatiotemporal resolution of both input parameters) generates an overestimation of Aerosol Optical Depth (AOD). Although it is able to qualitatively reproduce the temporal trend of the dust event, the default configuration of NMM-dust cannot fully capture its actual spatial distribution. Adjusting the spatiotemporal resolution of soil moisture and vegetation cover datasets showed that the model is sensitive to both parameters. Increasing the spatiotemporal resolution of soil moisture effectively reduces model's overestimation of AOD, while increasing the spatiotemporal resolution of vegetation cover changes the spatial distribution of reproduced dust storm. The adjustment of both parameters enables NMM-dust to capture the spatial distribution of dust storms, as well as reproducing more accurate dust concentration.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Naughton, M.J.; Bourke, W.; Browning, G.L.

The convergence of spectral model numerical solutions of the global shallow-water equations is examined as a function of the time step and the spectral truncation. The contributions to the errors due to the spatial and temporal discretizations are separately identified and compared. Numerical convergence experiments are performed with the inviscid equations from smooth (Rossby-Haurwitz wave) and observed (R45 atmospheric analysis) initial conditions, and also with the diffusive shallow-water equations. Results are compared with the forced inviscid shallow-water equations case studied by Browning et al. Reduction of the time discretization error by the removal of fast waves from the solution usingmore » initialization is shown. The effects of forcing and diffusion on the convergence are discussed. Time truncation errors are found to dominate when a feature is large scale and well resolved; spatial truncation errors dominate for small-scale features and also for large scale after the small scales have affected them. Possible implications of these results for global atmospheric modeling are discussed. 31 refs., 14 figs., 4 tabs.« less

On the representation and estimation of spatial uncertainty. [for mobile robot

NASA Technical Reports Server (NTRS)

Smith, Randall C.; Cheeseman, Peter

1987-01-01

This paper describes a general method for estimating the nominal relationship and expected error (covariance) between coordinate frames representing the relative locations of objects. The frames may be known only indirectly through a series of spatial relationships, each with its associated error, arising from diverse causes, including positioning errors, measurement errors, or tolerances in part dimensions. This estimation method can be used to answer such questions as whether a camera attached to a robot is likely to have a particular reference object in its field of view. The calculated estimates agree well with those from an independent Monte Carlo simulation. The method makes it possible to decide in advance whether an uncertain relationship is known accurately enough for some task and, if not, how much of an improvement in locational knowledge a proposed sensor will provide. The method presented can be generalized to six degrees of freedom and provides a practical means of estimating the relationships (position and orientation) among objects, as well as estimating the uncertainty associated with the relationships.

Fast adaptive diamond search algorithm for block-matching motion estimation using spatial correlation

NASA Astrophysics Data System (ADS)

Park, Sang-Gon; Jeong, Dong-Seok

2000-12-01

In this paper, we propose a fast adaptive diamond search algorithm (FADS) for block matching motion estimation. Many fast motion estimation algorithms reduce the computational complexity by the UESA (Unimodal Error Surface Assumption) where the matching error monotonically increases as the search moves away from the global minimum point. Recently, many fast BMAs (Block Matching Algorithms) make use of the fact that global minimum points in real world video sequences are centered at the position of zero motion. But these BMAs, especially in large motion, are easily trapped into the local minima and result in poor matching accuracy. So, we propose a new motion estimation algorithm using the spatial correlation among the neighboring blocks. We move the search origin according to the motion vectors of the spatially neighboring blocks and their MAEs (Mean Absolute Errors). The computer simulation shows that the proposed algorithm has almost the same computational complexity with DS (Diamond Search), but enhances PSNR. Moreover, the proposed algorithm gives almost the same PSNR as that of FS (Full Search), even for the large motion with half the computational load.

Generalization of Prism Adaptation

ERIC Educational Resources Information Center

Redding, Gordon M.; Wallace, Benjamin

2006-01-01

Prism exposure produces 2 kinds of adaptive response. Recalibration is ordinary strategic remapping of spatially coded movement commands to rapidly reduce performance error. Realignment is the extraordinary process of transforming spatial maps to bring the origins of coordinate systems into correspondence. Realignment occurs when spatial…

The “Good Cop, Bad Cop” Effect in the RT-Based Concealed Information Test: Exploring the Effect of Emotional Expressions Displayed by a Virtual Investigator

PubMed Central

Varga, Mihai; Visu-Petra, George; Miclea, Mircea; Visu-Petra, Laura

2015-01-01

Concealing the possession of relevant information represents a complex cognitive process, shaped by contextual demands and individual differences in cognitive and socio-emotional functioning. The Reaction Time-based Concealed Information Test (RT-CIT) is used to detect concealed knowledge based on the difference in RTs between denying recognition of critical (probes) and newly encountered (irrelevant) information. Several research questions were addressed in this scenario implemented after a mock crime. First, we were interested whether the introduction of a social stimulus (facial identity) simulating a virtual investigator would facilitate the process of deception detection. Next, we explored whether his emotional displays (friendly, hostile or neutral) would have a differential impact on speed of responses to probe versus irrelevant items. We also compared the impact of introducing similar stimuli in a working memory (WM) updating context without requirements to conceal information. Finally, we explored the association between deceptive behavior and individual differences in WM updating proficiency or in internalizing problems (state / trait anxiety and depression). Results indicated that the mere presence of a neutral virtual investigator slowed down participants' responses, but not the appended lie-specific time (difference between probes and irrelevants). Emotional expression was shown to differentially affect speed of responses to critical items, with positive displays from the virtual examiner enhancing lie-specific time, compared to negative facial expressions, which had an opposite impact. This valence-specific effect was not visible in the WM updating context. Higher levels of trait / state anxiety were related to faster responses to probes in the negative condition (hostile facial expression) of the RT-CIT. These preliminary findings further emphasize the need to take into account motivational and emotional factors when considering the transfer of deception detection techniques from the laboratory to real-life settings. PMID:25699516

Psychometric Evaluation of the Pain Attitudes Questionnaire-Revised for People With Advanced Cancer.

PubMed

Mah, Kenneth; Tran, Kim T; Gauthier, Lynn R; Rodin, Gary; Zimmermann, Camilla; Warr, David; Librach, S Lawrence; Moore, Malcolm; Shepherd, Frances A; Gagliese, Lucia

2017-07-01

Pain-related stoicism and cautiousness are theorized to be more prevalent in older than younger patients and to lead to greater pain under-reporting and consequently inadequate pain management in older patients. The Pain Attitudes Questionnaire-Revised (PAQ-R), which measures 5 pain-related stoicism (fortitude, concealment, superiority) and cautiousness (self-doubt, reluctance) factors in chronic pain, can help test this hypothesis in advanced cancer but requires validation. We conducted a psychometric evaluation of the PAQ-R in 155 younger (younger than 60 years) and 114 older (aged 60 years and older) patients with advanced cancer. Participants showed disagreement with self-doubt items and floor effects with the subscale. Confirmatory factor analyses revealed good fit of the PAQ-R's 5 factors to younger and older groups' data but collinearity between fortitude and concealment. Multisample confirmatory factor analyses supported partial scalar invariance between age groups. Few hypothesized age-related differences were observed. Younger patients reported higher superiority scores than older patients. Whereas older patients showed greater fortitude and superiority with lower average pain intensity, younger patients showed greater concealment or fortitude with greater worst and average pain intensity. Furthermore, whereas older patients displayed greater superiority with lower interference in relations with others, younger patients displayed greater concealment and superiority with greater interference in walking ability and greater concealment and self-doubt with more interference in relations with others. Cross-validation of the PAQ-R's factor structure and identification of pathways to the factors and effect on pain-related outcomes using multivariate approaches are warranted. This article presents the psychometric properties of a measure of 2 particular pain-related attitudes. The measure can help clarify whether these attitudes adversely influence pain reporting in older patients with advanced cancer as hypothesized and, in turn, explain the inadequate pain management frequently reported with this clinical group. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.

Is anterior N2 enhancement a reliable electrophysiological index of concealed information?

PubMed

Ganis, Giorgio; Bridges, David; Hsu, Chun-Wei; Schendan, Haline E

2016-12-01

Concealed information tests (CITs) are used to determine whether an individual possesses information about an item of interest. Event-related potential (ERP) measures in CITs have focused almost exclusively on the P3b component, showing that this component is larger when lying about the item of interest (probe) than telling the truth about control items (irrelevants). Recent studies have begun to examine other ERP components, such as the anterior N2, with mixed results. A seminal CIT study found that visual probes elicit a larger anterior N2 than irrelevants (Gamer and Berti, 2010) and suggested that this component indexes cognitive control processes engaged when lying about probes. However, this study did not control for potential intrinsic differences among the stimuli: the same probe and irrelevants were used for all participants, and there was no control condition composed of uninformed participants. Here, first we show that the N2 effect found in the study by Gamer and Berti (2010) was in large part due to stimulus differences, as the effect observed in a concealed information condition was comparable to that found in two matched control conditions without any concealed information (Experiments 1 and 2). Next, we addressed the issue of the generality of the N2 findings by counterbalancing a new set of stimuli across participants and by using a control condition with uninformed participants (Experiment 3). Results show that the probe did not elicit a larger anterior N2 than the irrelevants under these controlled conditions. These findings suggest that caution should be taken in using the N2 as an index of concealed information in CITs. Furthermore, they are a reminder that results of CIT studies (not only with ERPs) performed without stimulus counterbalancing and suitable control conditions may be confounded by differential intrinsic properties of the stimuli employed. Copyright © 2016 Elsevier Inc. All rights reserved.

Concealed weapons detection using electromagnetic resonances

NASA Astrophysics Data System (ADS)

Hunt, Allen R.; Hogg, R. Douglas; Foreman, William

1998-12-01

Concealed weapons pose a significant threat to both law enforcement and security agency personnel. The uncontrolled environments associated with peacekeeping and the move toward relaxation of concealed weapons laws here in the U.S. provide a strong motivation for developing weapons detection technologies which are noninvasive and can function noncooperatively. Existing weapons detection systems are primarily oriented to detecting metal and require the cooperation of the person being searched. The new generation of detectors under development that focuses primarily on imaging methods, faces problems associated with privacy issues. There remains a need for a weapons detector which is portable, detects weapons remotely, avoids the issues associated with privacy rights, can tell the difference between car keys and a knife, and is affordable enough that one can be issued to every peacekeeper and law enforcement officer. AKELA is developing a concealed weapons detector that uses wideband radar techniques to excite natural electromagnetic resonances that characterize the size, shape, and material composition of an object. Neural network processing is used to classify the difference between weapons and nuisance objects. We have constructed both time and frequency domain test systems and used them to gather experimental data on a variety of armed and unarmed individuals. These experiments have been performed in an environment similar to the operational environment. Preliminary results from these experiments show that it is possible to detect a weapon being carried by an individual from a distance of 10 to 15 feet, and to detect a weapon being concealed behind the back. The power required is about 100 milliwatts. A breadboard system is being fabricated and will be used by AKELA and our law enforcement partner to gather data in operationally realistic situations. While a laptop computer will control the breadboard system, the wideband radar electronics will fit in a box the size of a CD ROM drive of a computer.

BATMAN: Bayesian Technique for Multi-image Analysis

NASA Astrophysics Data System (ADS)

Casado, J.; Ascasibar, Y.; García-Benito, R.; Guidi, G.; Choudhury, O. S.; Bellocchi, E.; Sánchez, S. F.; Díaz, A. I.

2017-04-01

This paper describes the Bayesian Technique for Multi-image Analysis (BATMAN), a novel image-segmentation technique based on Bayesian statistics that characterizes any astronomical data set containing spatial information and performs a tessellation based on the measurements and errors provided as input. The algorithm iteratively merges spatial elements as long as they are statistically consistent with carrying the same information (I.e. identical signal within the errors). We illustrate its operation and performance with a set of test cases including both synthetic and real integral-field spectroscopic data. The output segmentations adapt to the underlying spatial structure, regardless of its morphology and/or the statistical properties of the noise. The quality of the recovered signal represents an improvement with respect to the input, especially in regions with low signal-to-noise ratio. However, the algorithm may be sensitive to small-scale random fluctuations, and its performance in presence of spatial gradients is limited. Due to these effects, errors may be underestimated by as much as a factor of 2. Our analysis reveals that the algorithm prioritizes conservation of all the statistically significant information over noise reduction, and that the precise choice of the input data has a crucial impact on the results. Hence, the philosophy of BaTMAn is not to be used as a 'black box' to improve the signal-to-noise ratio, but as a new approach to characterize spatially resolved data prior to its analysis. The source code is publicly available at http://astro.ft.uam.es/SELGIFS/BaTMAn.

Scoping a field experiment: error diagnostics of TRMM precipitation radar estimates in complex terrain as a basis for IPHEx2014

NASA Astrophysics Data System (ADS)

Duan, Y.; Wilson, A. M.; Barros, A. P.

2014-10-01

A diagnostic analysis of the space-time structure of error in Quantitative Precipitation Estimates (QPE) from the Precipitation Radar (PR) on the Tropical Rainfall Measurement Mission (TRMM) satellite is presented here in preparation for the Integrated Precipitation and Hydrology Experiment (IPHEx) in 2014. IPHEx is the first NASA ground-validation field campaign after the launch of the Global Precipitation Measurement (GPM) satellite. In anticipation of GPM, a science-grade high-density raingauge network was deployed at mid to high elevations in the Southern Appalachian Mountains, USA since 2007. This network allows for direct comparison between ground-based measurements from raingauges and satellite-based QPE (specifically, PR 2A25 V7 using 5 years of data 2008-2013). Case studies were conducted to characterize the vertical profiles of reflectivity and rain rate retrievals associated with large discrepancies with respect to ground measurements. The spatial and temporal distribution of detection errors (false alarm, FA, and missed detection, MD) and magnitude errors (underestimation, UND, and overestimation, OVR) for stratiform and convective precipitation are examined in detail toward elucidating the physical basis of retrieval error. The diagnostic error analysis reveals that detection errors are linked to persistent stratiform light rainfall in the Southern Appalachians, which explains the high occurrence of FAs throughout the year, as well as the diurnal MD maximum at midday in the cold season (fall and winter), and especially in the inner region. Although UND dominates the magnitude error budget, underestimation of heavy rainfall conditions accounts for less than 20% of the total consistent with regional hydrometeorology. The 2A25 V7 product underestimates low level orographic enhancement of rainfall associated with fog, cap clouds and cloud to cloud feeder-seeder interactions over ridges, and overestimates light rainfall in the valleys by large amounts, though this behavior is strongly conditioned by the coarse spatial resolution (5 km) of the terrain topography mask used to remove ground clutter effects. Precipitation associated with small-scale systems (< 25 km2) and isolated deep convection tends to be underestimated, which we attribute to non-uniform beam-filling effects due to spatial averaging of reflectivity at the PR resolution. Mixed precipitation events (i.e., cold fronts and snow showers) fall into OVR or FA categories, but these are also the types of events for which observations from standard ground-based raingauge networks are more likely subject to measurement uncertainty, that is raingauge underestimation errors due to under-catch and precipitation phase. Overall, the space-time structure of the errors shows strong links among precipitation, envelope orography, landform (ridge-valley contrasts), and local hydrometeorological regime that is strongly modulated by the diurnal cycle, pointing to three major error causes that are inter-related: (1) representation of concurrent vertically and horizontally varying microphysics; (2) non uniform beam filling (NUBF) effects and ambiguity in the detection of bright band position; and (3) spatial resolution and ground clutter correction.

Scoping a field experiment: error diagnostics of TRMM precipitation radar estimates in complex terrain as a basis for IPHEx2014

NASA Astrophysics Data System (ADS)

Duan, Y.; Wilson, A. M.; Barros, A. P.

2015-03-01

A diagnostic analysis of the space-time structure of error in quantitative precipitation estimates (QPEs) from the precipitation radar (PR) on the Tropical Rainfall Measurement Mission (TRMM) satellite is presented here in preparation for the Integrated Precipitation and Hydrology Experiment (IPHEx) in 2014. IPHEx is the first NASA ground-validation field campaign after the launch of the Global Precipitation Measurement (GPM) satellite. In anticipation of GPM, a science-grade high-density raingauge network was deployed at mid to high elevations in the southern Appalachian Mountains, USA, since 2007. This network allows for direct comparison between ground-based measurements from raingauges and satellite-based QPE (specifically, PR 2A25 Version 7 using 5 years of data 2008-2013). Case studies were conducted to characterize the vertical profiles of reflectivity and rain rate retrievals associated with large discrepancies with respect to ground measurements. The spatial and temporal distribution of detection errors (false alarm, FA; missed detection, MD) and magnitude errors (underestimation, UND; overestimation, OVR) for stratiform and convective precipitation are examined in detail toward elucidating the physical basis of retrieval error. The diagnostic error analysis reveals that detection errors are linked to persistent stratiform light rainfall in the southern Appalachians, which explains the high occurrence of FAs throughout the year, as well as the diurnal MD maximum at midday in the cold season (fall and winter) and especially in the inner region. Although UND dominates the error budget, underestimation of heavy rainfall conditions accounts for less than 20% of the total, consistent with regional hydrometeorology. The 2A25 V7 product underestimates low-level orographic enhancement of rainfall associated with fog, cap clouds and cloud to cloud feeder-seeder interactions over ridges, and overestimates light rainfall in the valleys by large amounts, though this behavior is strongly conditioned by the coarse spatial resolution (5 km) of the topography mask used to remove ground-clutter effects. Precipitation associated with small-scale systems (< 25 km2) and isolated deep convection tends to be underestimated, which we attribute to non-uniform beam-filling effects due to spatial averaging of reflectivity at the PR resolution. Mixed precipitation events (i.e., cold fronts and snow showers) fall into OVR or FA categories, but these are also the types of events for which observations from standard ground-based raingauge networks are more likely subject to measurement uncertainty, that is raingauge underestimation errors due to undercatch and precipitation phase. Overall, the space-time structure of the errors shows strong links among precipitation, envelope orography, landform (ridge-valley contrasts), and a local hydrometeorological regime that is strongly modulated by the diurnal cycle, pointing to three major error causes that are inter-related: (1) representation of concurrent vertically and horizontally varying microphysics; (2) non-uniform beam filling (NUBF) effects and ambiguity in the detection of bright band position; and (3) spatial resolution and ground-clutter correction.

Midline Body Actions and Leftward Spatial “Aiming” in Patients with Spatial Neglect

PubMed Central

Chaudhari, Amit; Pigott, Kara; Barrett, A. M.

2015-01-01

Spatial motor–intentional “Aiming” bias is a dysfunction in initiation/execution of motor–intentional behavior, resulting in hypokinetic and hypometric leftward movements. Aiming bias may contribute to posture, balance, and movement problems and uniquely account for disability in post-stroke spatial neglect. Body movement may modify and even worsen Aiming errors, but therapy techniques, such as visual scanning training, do not take this into account. Here, we evaluated (1) whether instructing neglect patients to move midline body parts improves their ability to explore left space and (2) whether this has a different impact on different patients. A 68-year-old woman with spatial neglect after a right basal ganglia infarct had difficulty orienting to and identifying left-sided objects. She was prompted with four instructions: “look to the left,” “point with your nose to the left,” “point with your [right] hand to the left,” and “stick out your tongue and point it to the left.” She oriented leftward dramatically better when pointing with the tongue/nose, than she did when pointing with the hand. We then tested nine more consecutive patients with spatial neglect using the same instructions. Only four of them made any orienting errors. Only one patient made >50% errors when pointing with the hand, and she did not benefit from pointing with the tongue/nose. We observed that pointing with the tongue could facilitate left-sided orientation in a stroke survivor with spatial neglect. If midline structures are represented more bilaterally, they may be less affected by Aiming bias. Alternatively, moving the body midline may be more permissive for leftward orienting than moving right body parts. We were not able to replicate this effect in another patient; we suspect that the magnitude of this effect may depend upon the degree to which patients have directional akinesia, spatial Where deficits, or cerebellar/frontal cortical lesions. Future research could examine these hypotheses. PMID:26217211

Comparison of direct and heterodyne detection optical intersatellite communication links

NASA Technical Reports Server (NTRS)

Chen, C. C.; Gardner, C. S.

1987-01-01

The performance of direct and heterodyne detection optical intersatellite communication links are evaluated and compared. It is shown that the performance of optical links is very sensitive to the pointing and tracking errors at the transmitter and receiver. In the presence of random pointing and tracking errors, optimal antenna gains exist that will minimize the required transmitter power. In addition to limiting the antenna gains, random pointing and tracking errors also impose a power penalty in the link budget. This power penalty is between 1.6 to 3 dB for a direct detection QPPM link, and 3 to 5 dB for a heterodyne QFSK system. For the heterodyne systems, the carrier phase noise presents another major factor of performance degradation that must be considered. In contrast, the loss due to synchronization error is small. The link budgets for direct and heterodyne detection systems are evaluated. It is shown that, for systems with large pointing and tracking errors, the link budget is dominated by the spatial tracking error, and the direct detection system shows a superior performance because it is less sensitive to the spatial tracking error. On the other hand, for systems with small pointing and tracking jitters, the antenna gains are in general limited by the launch cost, and suboptimal antenna gains are often used in practice. In which case, the heterodyne system has a slightly higher power margin because of higher receiver sensitivity.

Spatial-temporal features of thermal images for Carpal Tunnel Syndrome detection

NASA Astrophysics Data System (ADS)

Estupinan Roldan, Kevin; Ortega Piedrahita, Marco A.; Benitez, Hernan D.

2014-02-01

Disorders associated with repeated trauma account for about 60% of all occupational illnesses, Carpal Tunnel Syndrome (CTS) being the most consulted today. Infrared Thermography (IT) has come to play an important role in the field of medicine. IT is non-invasive and detects diseases based on measuring temperature variations. IT represents a possible alternative to prevalent methods for diagnosis of CTS (i.e. nerve conduction studies and electromiography). This work presents a set of spatial-temporal features extracted from thermal images taken in healthy and ill patients. Support Vector Machine (SVM) classifiers test this feature space with Leave One Out (LOO) validation error. The results of the proposed approach show linear separability and lower validation errors when compared to features used in previous works that do not account for temperature spatial variability.

Invisibility Cloak Printed on a Photonic Chip

PubMed Central

Feng, Zhen; Wu, Bing-Hong; Zhao, Yu-Xi; Gao, Jun; Qiao, Lu-Feng; Yang, Ai-Lin; Lin, Xiao-Feng; Jin, Xian-Min

2016-01-01

Invisibility cloak capable of hiding an object can be achieved by properly manipulating electromagnetic field. Such a remarkable ability has been shown in transformation and ray optics. Alternatively, it may be realistic to create a spatial cloak by means of confining electromagnetic field in three-dimensional arrayed waveguides and introducing appropriate collective curvature surrounding an object. We realize the artificial structure in borosilicate by femtosecond laser direct writing, where we prototype up to 5,000 waveguides to conceal millimeter-scale volume. We characterize the performance of the cloak by normalized cross correlation, tomography analysis and continuous three-dimensional viewing angle scan. Our results show invisibility cloak can be achieved in waveguide optics. Furthermore, directly printed invisibility cloak on a photonic chip may enable controllable study and novel applications in classical and quantum integrated photonics, such as invisualising a coupling or swapping operation with on-chip circuits of their own. PMID:27329510

Cases of violence involving transvestites and transsexuals in a northeastern Brazilian city.

PubMed

Silva, Glauber Weder Dos Santos; Souza, Emanoel Fhilipe Leite; Sena, Romeika Carla Ferreira de; Moura, Izabella Bezerra de Lima; Sobreira, Maura Vanessa Silva; Miranda, Francisco Arnoldo Nunes de

2016-06-01

Objective To analyze cases of violence against transvestites and transsexuals based on their sociodemographic profile. Method Cross-sectional, descriptive research performed in Cajazeiras / Paraíba, consisting of 16 transvestites and transsexuals. Data collection took place in April 2014 and was analyzed descriptively. Results The typology of violence that victimized transvestites and transsexuals were: verbal (91.96%), psychological (58.33%) and physical (33.33%), often between 24 hours and six months preceding the survey. Regarding the spatiality: the street, school and health services were all scenarios of aggression. With respect to the offending agent, the findings point towards neighbors, family members and health professionals. All forms of violence happened between agents and spaces of aggression. Conclusions Violence among this population, silence around the situations of abuse became more pronounced as did its invisibility in the social and institutional context, reflecting the inhibition of human rights and concealment of reality.

Study on multispectral imaging detection and recognition

NASA Astrophysics Data System (ADS)

Jun, Wang; Na, Ding; Gao, Jiaobo; Yu, Hu; Jun, Wu; Li, Junna; Zheng, Yawei; Fei, Gao; Sun, Kefeng

2009-07-01

Multispectral imaging detecting technology use target radiation character in spectral spatial distribution and relation between spectral and image to detect target and remote sensing measure. Its speciality is multi channel, narrow bandwidth, large amount of information, high accuracy. The ability of detecting target in environment of clutter, camouflage, concealment and beguilement is improved. At present, spectral imaging technology in the range of multispectral and hyperspectral develop greatly. The multispectral imaging equipment of unmanned aerial vehicle can be used in mine detection, information, surveillance and reconnaissance. Spectral imaging spectrometer operating in MWIR and LWIR has already been applied in the field of remote sensing and military in the advanced country. The paper presents the technology of multispectral imaging. It can enhance the reflectance, scatter and radiation character of the artificial targets among nature background. The targets among complex background and camouflage/stealth targets can be effectively identified. The experiment results and the data of spectral imaging is obtained.

Mapping wildland fuels for fire management across multiple scales: integrating remote sensing, GIS, and biophysical modeling

USGS Publications Warehouse

Keane, Robert E.; Burgan, Robert E.; Van Wagtendonk, Jan W.

2001-01-01

Fuel maps are essential for computing spatial fire hazard and risk and simulating fire growth and intensity across a landscape. However, fuel mapping is an extremely difficult and complex process requiring expertise in remotely sensed image classification, fire behavior, fuels modeling, ecology, and geographical information systems (GIS). This paper first presents the challenges of mapping fuels: canopy concealment, fuelbed complexity, fuel type diversity, fuel variability, and fuel model generalization. Then, four approaches to mapping fuels are discussed with examples provided from the literature: (1) field reconnaissance; (2) direct mapping methods; (3) indirect mapping methods; and (4) gradient modeling. A fuel mapping method is proposed that uses current remote sensing and image processing technology. Future fuel mapping needs are also discussed which include better field data and fuel models, accurate GIS reference layers, improved satellite imagery, and comprehensive ecosystem models.

A Geothermal GIS for Nevada: Defining Regional Controls and Favorable Exploration Terrains for Extensional Geothermal Systems

USGS Publications Warehouse

Coolbaugh, M.F.; Taranik, J.V.; Raines, G.L.; Shevenell, L.A.; Sawatzky, D.L.; Bedell, R.; Minor, T.B.

2002-01-01

Spatial analysis with a GIS was used to evaluate geothermal systems in Nevada using digital maps of geology, heat flow, young faults, young volcanism, depth to groundwater, groundwater geochemistry, earthquakes, and gravity. High-temperature (>160??C) extensional geothermal systems are preferentially associated with northeast-striking late Pleistocene and younger faults, caused by crustal extension, which in most of Nevada is currently oriented northwesterly (as measured by GPS). The distribution of sparse young (160??C) geothermal systems in Nevada are more likely to occur in areas where the groundwater table is shallow (<30m). Undiscovered geothermal systems may occur where groundwater levels are deeper and hot springs do not issue at the surface. A logistic regression exploration model was developed for geothermal systems, using young faults, young volcanics, positive gravity anomalies, and earthquakes to predict areas where deeper groundwater tables are most likely to conceal geothermal systems.

Invisibility Cloak Printed on a Photonic Chip

NASA Astrophysics Data System (ADS)

Feng, Zhen; Wu, Bing-Hong; Zhao, Yu-Xi; Gao, Jun; Qiao, Lu-Feng; Yang, Ai-Lin; Lin, Xiao-Feng; Jin, Xian-Min

2016-06-01

Invisibility cloak capable of hiding an object can be achieved by properly manipulating electromagnetic field. Such a remarkable ability has been shown in transformation and ray optics. Alternatively, it may be realistic to create a spatial cloak by means of confining electromagnetic field in three-dimensional arrayed waveguides and introducing appropriate collective curvature surrounding an object. We realize the artificial structure in borosilicate by femtosecond laser direct writing, where we prototype up to 5,000 waveguides to conceal millimeter-scale volume. We characterize the performance of the cloak by normalized cross correlation, tomography analysis and continuous three-dimensional viewing angle scan. Our results show invisibility cloak can be achieved in waveguide optics. Furthermore, directly printed invisibility cloak on a photonic chip may enable controllable study and novel applications in classical and quantum integrated photonics, such as invisualising a coupling or swapping operation with on-chip circuits of their own.

Habitat drives dispersal and survival of translocated juvenile desert tortoises

USGS Publications Warehouse

Nafus, Melia G.; Esque, Todd C.; Averill-Murray, Roy C.; Nussear, Kenneth E.; Swaisgood, Ronald R.

2017-01-01

5.Synthesis and applications. Resource managers using translocations as a conservation tool should prioritize acquiring data linking habitat to fitness. In particular, for species that depend on avoiding detection, refuges such as burrows and habitat that improved concealment had notable ability to improve survival and dispersal. Our study on juvenile Mojave desert tortoises showed that refuge availability or the distributions of habitat appropriate for concealment are important considerations for identifying translocation sites for species highly dependent on crypsis, camouflage, or other forms of habitat matching.

Training Objectives for Tank Platoon Leaders Covering Tasks Performed during Four Armor Operations

DTIC Science & Technology

1983-01-01

screens to conceal their movement to covered and concealed positions. The M250 grenade launcher consists of two six-barreled dischargers wired for two...generates smoke by the injestion of fuel onto the hot engine exhaust system. The smoke screen generated by VEESS is used to compli- ment the M250 smoke...grenade system by reinforcing and sustaining the screen created by the M250 system. The purpose of the smoke producing systems is to make it more

Comparative assessment of LANDSAT-D MSS and TM data quality for mapping applications in the Southeast

NASA Technical Reports Server (NTRS)

1984-01-01

Rectifications of multispectral scanner and thematic mapper data sets for full and subscene areas, analyses of planimetric errors, assessments of the number and distribution of ground control points required to minimize errors, and factors contributing to error residual are examined. Other investigations include the generation of three dimensional terrain models and the effects of spatial resolution on digital classification accuracies.

Characteristics of Chinese-English bilingual dyslexia in right occipito-temporal lesion.

PubMed

Ting, Simon Kang Seng; Chia, Pei Shi; Chan, Yiong Huak; Kwek, Kevin Jun Hong; Tan, Wilnard; Hameed, Shahul; Tan, Eng-King

2017-11-01

Current literature suggests that right hemisphere lesions produce predominant spatial-related dyslexic error in English speakers. However, little is known regarding such lesions in Chinese speakers. In this paper, we describe the dyslexic characteristics of a Chinese-English bilingual patient with a right posterior cortical lesion. He was found to have profound spatial-related errors during his English word reading, in both real and non-words. During Chinese word reading, there was significantly less error compared to English, probably due to the ideographic nature of the Chinese language. He was also found to commit phonological-like visual errors in English, characterized by error responses that were visually similar to the actual word. There was no significant difference in visual errors during English word reading compared with Chinese. In general, our patient's performance in both languages appears to be consistent with the current literature on right posterior hemisphere lesions. Additionally, his performance also likely suggests that the right posterior cortical region participates in the visual analysis of orthographical word representation, both in ideographical and alphabetic languages, at least from a bilingual perspective. Future studies should further examine the role of the right posterior region in initial visual analysis of both languages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of random errors in planar PIV data on pressure estimation in vortex dominated flows

NASA Astrophysics Data System (ADS)

McClure, Jeffrey; Yarusevych, Serhiy

2015-11-01

The sensitivity of pressure estimation techniques from Particle Image Velocimetry (PIV) measurements to random errors in measured velocity data is investigated using the flow over a circular cylinder as a test case. Direct numerical simulations are performed for ReD = 100, 300 and 1575, spanning laminar, transitional, and turbulent wake regimes, respectively. A range of random errors typical for PIV measurements is applied to synthetic PIV data extracted from numerical results. A parametric study is then performed using a number of common pressure estimation techniques. Optimal temporal and spatial resolutions are derived based on the sensitivity of the estimated pressure fields to the simulated random error in velocity measurements, and the results are compared to an optimization model derived from error propagation theory. It is shown that the reductions in spatial and temporal scales at higher Reynolds numbers leads to notable changes in the optimal pressure evaluation parameters. The effect of smaller scale wake structures is also quantified. The errors in the estimated pressure fields are shown to depend significantly on the pressure estimation technique employed. The results are used to provide recommendations for the use of pressure and force estimation techniques from experimental PIV measurements in vortex dominated laminar and turbulent wake flows.

Improving the spatial and temporal resolution with quantification of uncertainty and errors in earth observation data sets using Data Interpolating Empirical Orthogonal Functions methodology

NASA Astrophysics Data System (ADS)

El Serafy, Ghada; Gaytan Aguilar, Sandra; Ziemba, Alexander

2016-04-01

There is an increasing use of process-based models in the investigation of ecological systems and scenario predictions. The accuracy and quality of these models are improved when run with high spatial and temporal resolution data sets. However, ecological data can often be difficult to collect which manifests itself through irregularities in the spatial and temporal domain of these data sets. Through the use of Data INterpolating Empirical Orthogonal Functions(DINEOF) methodology, earth observation products can be improved to have full spatial coverage within the desired domain as well as increased temporal resolution to daily and weekly time step, those frequently required by process-based models[1]. The DINEOF methodology results in a degree of error being affixed to the refined data product. In order to determine the degree of error introduced through this process, the suspended particulate matter and chlorophyll-a data from MERIS is used with DINEOF to produce high resolution products for the Wadden Sea. These new data sets are then compared with in-situ and other data sources to determine the error. Also, artificial cloud cover scenarios are conducted in order to substantiate the findings from MERIS data experiments. Secondly, the accuracy of DINEOF is explored to evaluate the variance of the methodology. The degree of accuracy is combined with the overall error produced by the methodology and reported in an assessment of the quality of DINEOF when applied to resolution refinement of chlorophyll-a and suspended particulate matter in the Wadden Sea. References [1] Sirjacobs, D.; Alvera-Azcárate, A.; Barth, A.; Lacroix, G.; Park, Y.; Nechad, B.; Ruddick, K.G.; Beckers, J.-M. (2011). Cloud filling of ocean colour and sea surface temperature remote sensing products over the Southern North Sea by the Data Interpolating Empirical Orthogonal Functions methodology. J. Sea Res. 65(1): 114-130. Dx.doi.org/10.1016/j.seares.2010.08.002

Visuo-vestibular interaction: predicting the position of a visual target during passive body rotation.

PubMed

Mackrous, I; Simoneau, M

2011-11-10

Following body rotation, optimal updating of the position of a memorized target is attained when retinal error is perceived and corrective saccade is performed. Thus, it appears that these processes may enable the calibration of the vestibular system by facilitating the sharing of information between both reference frames. Here, it is assessed whether having sensory information regarding body rotation in the target reference frame could enhance an individual's learning rate to predict the position of an earth-fixed target. During rotation, participants had to respond when they felt their body midline had crossed the position of the target and received knowledge of result. During practice blocks, for two groups, visual cues were displayed in the same reference frame of the target, whereas a third group relied on vestibular information (vestibular-only group) to predict the location of the target. Participants, unaware of the role of the visual cues (visual cues group), learned to predict the location of the target and spatial error decreased from 16.2 to 2.0°, reflecting a learning rate of 34.08 trials (determined from fitting a falling exponential model). In contrast, the group aware of the role of the visual cues (explicit visual cues group) showed a faster learning rate (i.e. 2.66 trials) but similar final spatial error 2.9°. For the vestibular-only group, similar accuracy was achieved (final spatial error of 2.3°), but their learning rate was much slower (i.e. 43.29 trials). Transferring to the Post-test (no visual cues and no knowledge of result) increased the spatial error of the explicit visual cues group (9.5°), but it did not change the performance of the vestibular group (1.2°). Overall, these results imply that cognition assists the brain in processing the sensory information within the target reference frame. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Local Use-Dependent Sleep in Wakefulness Links Performance Errors to Learning

PubMed Central

Quercia, Angelica; Zappasodi, Filippo; Committeri, Giorgia; Ferrara, Michele

2018-01-01

Sleep and wakefulness are no longer to be considered as discrete states. During wakefulness brain regions can enter a sleep-like state (off-periods) in response to a prolonged period of activity (local use-dependent sleep). Similarly, during nonREM sleep the slow-wave activity, the hallmark of sleep plasticity, increases locally in brain regions previously involved in a learning task. Recent studies have demonstrated that behavioral performance may be impaired by off-periods in wake in task-related regions. However, the relation between off-periods in wake, related performance errors and learning is still untested in humans. Here, by employing high density electroencephalographic (hd-EEG) recordings, we investigated local use-dependent sleep in wake, asking participants to repeat continuously two intensive spatial navigation tasks. Critically, one task relied on previous map learning (Wayfinding) while the other did not (Control). Behaviorally awake participants, who were not sleep deprived, showed progressive increments of delta activity only during the learning-based spatial navigation task. As shown by source localization, delta activity was mainly localized in the left parietal and bilateral frontal cortices, all regions known to be engaged in spatial navigation tasks. Moreover, during the Wayfinding task, these increments of delta power were specifically associated with errors, whose probability of occurrence was significantly higher compared to the Control task. Unlike the Wayfinding task, during the Control task neither delta activity nor the number of errors increased progressively. Furthermore, during the Wayfinding task, both the number and the amplitude of individual delta waves, as indexes of neuronal silence in wake (off-periods), were significantly higher during errors than hits. Finally, a path analysis linked the use of the spatial navigation circuits undergone to learning plasticity to off periods in wake. In conclusion, local sleep regulation in wakefulness, associated with performance failures, could be functionally linked to learning-related cortical plasticity. PMID:29666574

Impacts of visuomotor sequence learning methods on speed and accuracy: Starting over from the beginning or from the point of error.

PubMed

Tanaka, Kanji; Watanabe, Katsumi

2016-02-01

The present study examined whether sequence learning led to more accurate and shorter performance time if people who are learning a sequence start over from the beginning when they make an error (i.e., practice the whole sequence) or only from the point of error (i.e., practice a part of the sequence). We used a visuomotor sequence learning paradigm with a trial-and-error procedure. In Experiment 1, we found fewer errors, and shorter performance time for those who restarted their performance from the beginning of the sequence as compared to those who restarted from the point at which an error occurred, indicating better learning of spatial and motor representations of the sequence. This might be because the learned elements were repeated when the next performance started over from the beginning. In subsequent experiments, we increased the occasions for the repetitions of learned elements by modulating the number of fresh start points in the sequence after errors. The results showed that fewer fresh start points were likely to lead to fewer errors and shorter performance time, indicating that the repetitions of learned elements enabled participants to develop stronger spatial and motor representations of the sequence. Thus, a single or two fresh start points in the sequence (i.e., starting over only from the beginning or from the beginning or midpoint of the sequence after errors) is likely to lead to more accurate and faster performance. Copyright © 2016 Elsevier B.V. All rights reserved.

Error Estimation in an Optimal Interpolation Scheme for High Spatial and Temporal Resolution SST Analyses

NASA Technical Reports Server (NTRS)

Rigney, Matt; Jedlovec, Gary; LaFontaine, Frank; Shafer, Jaclyn

2010-01-01

Heat and moisture exchange between ocean surface and atmosphere plays an integral role in short-term, regional NWP. Current SST products lack both spatial and temporal resolution to accurately capture small-scale features that affect heat and moisture flux. NASA satellite is used to produce high spatial and temporal resolution SST analysis using an OI technique.

Object Identity in Infancy: The Interaction of Spatial Location Codes in Determining Search Errors

ERIC Educational Resources Information Center

Butterworth, George

1975-01-01

Reports two experiments which were designed to establish whether errors in infants' manual searches for objects are caused by changes in the location of an object or by the change in the relation between old and new hiding places. (JMB)

Sound localization skills in children who use bilateral cochlear implants and in children with normal acoustic hearing

PubMed Central

Grieco-Calub, Tina M.; Litovsky, Ruth Y.

2010-01-01

Objectives To measure sound source localization in children who have sequential bilateral cochlear implants (BICIs); to determine if localization accuracy correlates with performance on a right-left discrimination task (i.e., spatial acuity); to determine if there is a measurable bilateral benefit on a sound source identification task (i.e., localization accuracy) by comparing performance under bilateral and unilateral listening conditions; to determine if sound source localization continues to improve with longer durations of bilateral experience. Design Two groups of children participated in this study: a group of 21 children who received BICIs in sequential procedures (5–14 years old) and a group of 7 typically-developing children with normal acoustic hearing (5 years old). Testing was conducted in a large sound-treated booth with loudspeakers positioned on a horizontal arc with a radius of 1.2 m. Children participated in two experiments that assessed spatial hearing skills. Spatial hearing acuity was assessed with a discrimination task in which listeners determined if a sound source was presented on the right or left side of center; the smallest angle at which performance on this task was reliably above chance is the minimum audible angle. Sound localization accuracy was assessed with a sound source identification task in which children identified the perceived position of the sound source from a multi-loudspeaker array (7 or 15); errors are quantified using the root-mean-square (RMS) error. Results Sound localization accuracy was highly variable among the children with BICIs, with RMS errors ranging from 19°–56°. Performance of the NH group, with RMS errors ranging from 9°–29° was significantly better. Within the BICI group, in 11/21 children RMS errors were smaller in the bilateral vs. unilateral listening condition, indicating bilateral benefit. There was a significant correlation between spatial acuity and sound localization accuracy (R2=0.68, p<0.01), suggesting that children who achieve small RMS errors tend to have the smallest MAAs. Although there was large intersubject variability, testing of 11 children in the BICI group at two sequential visits revealed a subset of children who show improvement in spatial hearing skills over time. Conclusions A subset of children who use sequential BICIs can acquire sound localization abilities, even after long intervals between activation of hearing in the first- and second-implanted ears. This suggests that children with activation of the second implant later in life may be capable of developing spatial hearing abilities. The large variability in performance among the children with BICIs suggests that maturation of sound localization abilities in children with BICIs may be dependent on various individual subject factors such as age of implantation and chronological age. PMID:20592615

The propagation of inventory-based positional errors into statistical landslide susceptibility models

NASA Astrophysics Data System (ADS)

Steger, Stefan; Brenning, Alexander; Bell, Rainer; Glade, Thomas

2016-12-01

There is unanimous agreement that a precise spatial representation of past landslide occurrences is a prerequisite to produce high quality statistical landslide susceptibility models. Even though perfectly accurate landslide inventories rarely exist, investigations of how landslide inventory-based errors propagate into subsequent statistical landslide susceptibility models are scarce. The main objective of this research was to systematically examine whether and how inventory-based positional inaccuracies of different magnitudes influence modelled relationships, validation results, variable importance and the visual appearance of landslide susceptibility maps. The study was conducted for a landslide-prone site located in the districts of Amstetten and Waidhofen an der Ybbs, eastern Austria, where an earth-slide point inventory was available. The methodological approach comprised an artificial introduction of inventory-based positional errors into the present landslide data set and an in-depth evaluation of subsequent modelling results. Positional errors were introduced by artificially changing the original landslide position by a mean distance of 5, 10, 20, 50 and 120 m. The resulting differently precise response variables were separately used to train logistic regression models. Odds ratios of predictor variables provided insights into modelled relationships. Cross-validation and spatial cross-validation enabled an assessment of predictive performances and permutation-based variable importance. All analyses were additionally carried out with synthetically generated data sets to further verify the findings under rather controlled conditions. The results revealed that an increasing positional inventory-based error was generally related to increasing distortions of modelling and validation results. However, the findings also highlighted that interdependencies between inventory-based spatial inaccuracies and statistical landslide susceptibility models are complex. The systematic comparisons of 12 models provided valuable evidence that the respective error-propagation was not only determined by the degree of positional inaccuracy inherent in the landslide data, but also by the spatial representation of landslides and the environment, landslide magnitude, the characteristics of the study area, the selected classification method and an interplay of predictors within multiple variable models. Based on the results, we deduced that a direct propagation of minor to moderate inventory-based positional errors into modelling results can be partly counteracted by adapting the modelling design (e.g. generalization of input data, opting for strongly generalizing classifiers). Since positional errors within landslide inventories are common and subsequent modelling and validation results are likely to be distorted, the potential existence of inventory-based positional inaccuracies should always be considered when assessing landslide susceptibility by means of empirical models.

Influence of survey strategy and interpolation model on DEM quality

NASA Astrophysics Data System (ADS)

Heritage, George L.; Milan, David J.; Large, Andrew R. G.; Fuller, Ian C.

2009-11-01

Accurate characterisation of morphology is critical to many studies in the field of geomorphology, particularly those dealing with changes over time. Digital elevation models (DEMs) are commonly used to represent morphology in three dimensions. The quality of the DEM is largely a function of the accuracy of individual survey points, field survey strategy, and the method of interpolation. Recommendations concerning field survey strategy and appropriate methods of interpolation are currently lacking. Furthermore, the majority of studies to date consider error to be uniform across a surface. This study quantifies survey strategy and interpolation error for a gravel bar on the River Nent, Blagill, Cumbria, UK. Five sampling strategies were compared: (i) cross section; (ii) bar outline only; (iii) bar and chute outline; (iv) bar and chute outline with spot heights; and (v) aerial LiDAR equivalent, derived from degraded terrestrial laser scan (TLS) data. Digital Elevation Models were then produced using five different common interpolation algorithms. Each resultant DEM was differentiated from a terrestrial laser scan of the gravel bar surface in order to define the spatial distribution of vertical and volumetric error. Overall triangulation with linear interpolation (TIN) or point kriging appeared to provide the best interpolators for the bar surface. Lowest error on average was found for the simulated aerial LiDAR survey strategy, regardless of interpolation technique. However, comparably low errors were also found for the bar-chute-spot sampling strategy when TINs or point kriging was used as the interpolator. The magnitude of the errors between survey strategy exceeded those found between interpolation technique for a specific survey strategy. Strong relationships between local surface topographic variation (as defined by the standard deviation of vertical elevations in a 0.2-m diameter moving window), and DEM errors were also found, with much greater errors found at slope breaks such as bank edges. A series of curves are presented that demonstrate these relationships for each interpolation and survey strategy. The simulated aerial LiDAR data set displayed the lowest errors across the flatter surfaces; however, sharp slope breaks are better modelled by the morphologically based survey strategy. The curves presented have general application to spatially distributed data of river beds and may be applied to standard deviation grids to predict spatial error within a surface, depending upon sampling strategy and interpolation algorithm.

Computer-Controlled Cylindrical Polishing Process for Large X-Ray Mirror Mandrels

NASA Technical Reports Server (NTRS)

Khan, Gufran S.; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian

2010-01-01

We are developing high-energy grazing incidence shell optics for hard-x-ray telescopes. The resolution of a mirror shells depends on the quality of cylindrical mandrel from which they are being replicated. Mid-spatial-frequency axial figure error is a dominant contributor in the error budget of the mandrel. This paper presents our efforts to develop a deterministic cylindrical polishing process in order to keep the mid-spatial-frequency axial figure errors to a minimum. Simulation software is developed to model the residual surface figure errors of a mandrel due to the polishing process parameters and the tools used, as well as to compute the optical performance of the optics. The study carried out using the developed software was focused on establishing a relationship between the polishing process parameters and the mid-spatial-frequency error generation. The process parameters modeled are the speeds of the lap and the mandrel, the tool s influence function, the contour path (dwell) of the tools, their shape and the distribution of the tools on the polishing lap. Using the inputs from the mathematical model, a mandrel having conical approximated Wolter-1 geometry, has been polished on a newly developed computer-controlled cylindrical polishing machine. The preliminary results of a series of polishing experiments demonstrate a qualitative agreement with the developed model. We report our first experimental results and discuss plans for further improvements in the polishing process. The ability to simulate the polishing process is critical to optimize the polishing process, improve the mandrel quality and significantly reduce the cost of mandrel production

First- and second-language phonological representations in the mental lexicon.

PubMed

Sebastian-Gallés, Núria; Rodríguez-Fornells, Antoni; de Diego-Balaguer, Ruth; Díaz, Begoña

2006-08-01

Performance-based studies on the psychological nature of linguistic competence can conceal significant differences in the brain processes that underlie native versus nonnative knowledge of language. Here we report results from the brain activity of very proficient early bilinguals making a lexical decision task that illustrates this point. Two groups of Spanish-Catalan early bilinguals (Spanish-dominant and Catalan-dominant) were asked to decide whether a given form was a Catalan word or not. The nonwords were based on real words, with one vowel changed. In the experimental stimuli, the vowel change involved a Catalan-specific contrast that previous research had shown to be difficult for Spanish natives to perceive. In the control stimuli, the vowel switch involved contrasts common to Spanish and Catalan. The results indicated that the groups of bilinguals did not differ in their behavioral and event-related brain potential measurements for the control stimuli; both groups made very few errors and showed a larger N400 component for control nonwords than for control words. However, significant differences were observed for the experimental stimuli across groups: Specifically, Spanish-dominant bilinguals showed great difficulty in rejecting experimental nonwords. Indeed, these participants not only showed very high error rates for these stimuli, but also did not show an error-related negativity effect in their erroneous nonword decisions. However, both groups of bilinguals showed a larger correct-related negativity when making correct decisions about the experimental nonwords. The results suggest that although some aspects of a second language system may show a remarkable lack of plasticity (like the acquisition of some foreign contrasts), first-language representations seem to be more dynamic in their capacity of adapting and incorporating new information.

Patient safety culture in China: a case study in an outpatient setting in Beijing.

PubMed

Liu, Chaojie; Liu, Weiwei; Wang, Yuanyuan; Zhang, Zhihong; Wang, Peng

2014-07-01

To investigate the patient safety culture in an outpatient setting in Beijing and explore the meaning and implications of the safety culture from the perspective of health workers and patients. A mixed methods approach involving a questionnaire survey and in-depth interviews was adopted. Among the 410 invited staff members, 318 completed the Hospital Survey of Patient Safety Culture (HSOPC). Patient safety culture was described using 12 subscale scores. Inter-subscale correlation analysis, ANOVA and stepwise multivariate regression analyses were performed to identify the determinants of the patient safety culture scores. Interviewees included 22 patients selected through opportunity sampling and 27 staff members selected through purposive sampling. The interview data were analysed thematically. The survey respondents perceived high levels of unsafe care but had personally reported few events. Lack of 'communication openness' was identified as a major safety culture problem, and a perception of 'penalty' was the greatest barrier to the encouragement of error reporting. Cohesive 'teamwork within units', while found to be an area of strength, conversely served as a protective and defensive mechanism for medical practice. Low levels of trust between providers and consumers and lack of management support constituted an obstacle to building a positive patient safety culture. This study in China demonstrates that a punitive approach to error is still widespread despite increasing awareness of unsafe care, and managers have been slow in acknowledging the importance of building a positive patient safety culture. Strong 'teamwork within units', a common area of strength, could fuel the concealment of errors. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Spatio-temporal filtering for determination of common mode error in regional GNSS networks

NASA Astrophysics Data System (ADS)

Bogusz, Janusz; Gruszczynski, Maciej; Figurski, Mariusz; Klos, Anna

2015-04-01

The spatial correlation between different stations for individual components in the regional GNSS networks seems to be significant. The mismodelling in satellite orbits, the Earth orientation parameters (EOP), largescale atmospheric effects or satellite antenna phase centre corrections can all cause the regionally correlated errors. This kind of GPS time series errors are referred to as common mode errors (CMEs). They are usually estimated with the regional spatial filtering, such as the "stacking". In this paper, we show the stacking approach for the set of ASG-EUPOS permanent stations, assuming that spatial distribution of the CME is uniform over the whole region of Poland (more than 600 km extent). The ASG-EUPOS is a multifunctional precise positioning system based on the reference network designed for Poland. We used a 5- year span time series (2008-2012) of daily solutions in the ITRF2008 from Bernese 5.0 processed by the Military University of Technology EPN Local Analysis Centre (MUT LAC). At the beginning of our analyses concerning spatial dependencies, the correlation coefficients between each pair of the stations in the GNSS network were calculated. This analysis shows that spatio-temporal behaviour of the GPS-derived time series is not purely random, but there is the evident uniform spatial response. In order to quantify the influence of filtering using CME, the norms L1 and L2 were determined. The values of these norms were calculated for the North, East and Up components twice: before performing the filtration and after stacking. The observed reduction of the L1 and L2 norms was up to 30% depending on the dimension of the network. However, the question how to define an optimal size of CME-analysed subnetwork remains unanswered in this research, due to the fact that our network is not extended enough.

Spatio-temporal representativeness of ground-based downward solar radiation measurements

NASA Astrophysics Data System (ADS)

Schwarz, Matthias; Wild, Martin; Folini, Doris

2017-04-01

Surface solar radiation (SSR) is most directly observed with ground based pyranometer measurements. Besides measurement uncertainties, which arise from the pyranometer instrument itself, also errors attributed to the limited spatial representativeness of observations from single sites for their large-scale surrounding have to be taken into account when using such measurements for energy balance studies. In this study the spatial representativeness of 157 homogeneous European downward surface solar radiation time series from the Global Energy Balance Archive (GEBA) and the Baseline Surface Radiation Network (BSRN) were examined for the period 1983-2015 by using the high resolution (0.05°) surface solar radiation data set from the Satellite Application Facility on Climate Monitoring (CM-SAF SARAH) as a proxy for the spatiotemporal variability of SSR. By correlating deseasonalized monthly SSR time series form surface observations against single collocated satellite derived SSR time series, a mean spatial correlation pattern was calculated and validated against purely observational based patterns. Generally decreasing correlations with increasing distance from station, with high correlations (R2 = 0.7) in proximity to the observational sites (±0.5°), was found. When correlating surface observations against time series from spatially averaged satellite derived SSR data (and thereby simulating coarser and coarser grids), very high correspondence between sites and the collocated pixels has been found for pixel sizes up to several degrees. Moreover, special focus was put on the quantification of errors which arise in conjunction to spatial sampling when estimating the temporal variability and trends for a larger region from a single surface observation site. For 15-year trends on a 1° grid, errors due to spatial sampling in the order of half of the measurement uncertainty for monthly mean values were found.

Estimating riparian understory vegetation cover with beta regression and copula models

USGS Publications Warehouse

Eskelson, Bianca N.I.; Madsen, Lisa; Hagar, Joan C.; Temesgen, Hailemariam

2011-01-01

Understory vegetation communities are critical components of forest ecosystems. As a result, the importance of modeling understory vegetation characteristics in forested landscapes has become more apparent. Abundance measures such as shrub cover are bounded between 0 and 1, exhibit heteroscedastic error variance, and are often subject to spatial dependence. These distributional features tend to be ignored when shrub cover data are analyzed. The beta distribution has been used successfully to describe the frequency distribution of vegetation cover. Beta regression models ignoring spatial dependence (BR) and accounting for spatial dependence (BRdep) were used to estimate percent shrub cover as a function of topographic conditions and overstory vegetation structure in riparian zones in western Oregon. The BR models showed poor explanatory power (pseudo-R2 ≤ 0.34) but outperformed ordinary least-squares (OLS) and generalized least-squares (GLS) regression models with logit-transformed response in terms of mean square prediction error and absolute bias. We introduce a copula (COP) model that is based on the beta distribution and accounts for spatial dependence. A simulation study was designed to illustrate the effects of incorrectly assuming normality, equal variance, and spatial independence. It showed that BR, BRdep, and COP models provide unbiased parameter estimates, whereas OLS and GLS models result in slightly biased estimates for two of the three parameters. On the basis of the simulation study, 93–97% of the GLS, BRdep, and COP confidence intervals covered the true parameters, whereas OLS and BR only resulted in 84–88% coverage, which demonstrated the superiority of GLS, BRdep, and COP over OLS and BR models in providing standard errors for the parameter estimates in the presence of spatial dependence.

A spatially adaptive total variation regularization method for electrical resistance tomography

NASA Astrophysics Data System (ADS)

Song, Xizi; Xu, Yanbin; Dong, Feng

2015-12-01

The total variation (TV) regularization method has been used to solve the ill-posed inverse problem of electrical resistance tomography (ERT), owing to its good ability to preserve edges. However, the quality of the reconstructed images, especially in the flat region, is often degraded by noise. To optimize the regularization term and the regularization factor according to the spatial feature and to improve the resolution of reconstructed images, a spatially adaptive total variation (SATV) regularization method is proposed. A kind of effective spatial feature indicator named difference curvature is used to identify which region is a flat or edge region. According to different spatial features, the SATV regularization method can automatically adjust both the regularization term and regularization factor. At edge regions, the regularization term is approximate to the TV functional to preserve the edges; in flat regions, it is approximate to the first-order Tikhonov (FOT) functional to make the solution stable. Meanwhile, the adaptive regularization factor determined by the spatial feature is used to constrain the regularization strength of the SATV regularization method for different regions. Besides, a numerical scheme is adopted for the implementation of the second derivatives of difference curvature to improve the numerical stability. Several reconstruction image metrics are used to quantitatively evaluate the performance of the reconstructed results. Both simulation and experimental results indicate that, compared with the TV (mean relative error 0.288, mean correlation coefficient 0.627) and FOT (mean relative error 0.295, mean correlation coefficient 0.638) regularization methods, the proposed SATV (mean relative error 0.259, mean correlation coefficient 0.738) regularization method can endure a relatively high level of noise and improve the resolution of reconstructed images.

Factor structure and correlates of the Mandarin version of the Managing the Emotions of Others (MEOS) scale.

PubMed

Saklofske, Donald H; Austin, Elizabeth J; Yan, Gonggu; Smith, Martin M

2016-02-01

The English-language version of the Managing the Emotions of Others (MEOS) scale has been found to have a six-factor structure. This includes two pairs (Enhance, Divert and Worsen, Inauthentic) that respectively describe prosocial and non-prosocial interpersonal emotion management, together with an emotional concealment factor (Conceal) and a factor assessing poor self-rated emotional skills. A Mandarin translation of the MEOS was completed by 277 Chinese student participants. Factor analysis indicated a four-factor structure comprising a merged Enhance/Divert factor, together with Worsen, Inauthentic and Conceal factors. The emergence of a different factor structure compared to Western samples may be related to culture-dependent attitudes to emotional expression. The associations of the MEOS factors with Five-Factor model personality, the Dark Triad and trait emotional intelligence (EI) were examined; these were similar to but generally weaker than those found for the English-language version. © 2015 International Union of Psychological Science.

Body packing and intra-vaginal body pushing of cocaine: A case report.

PubMed

Wankhade, Vishwajit Kishor; Chikhalkar, B G

2018-03-01

Drug trafficking is an international problem. The prevalence of drug trafficking and newer concealing methods has been ever increasing. Body packing is described as using the abdominal or pelvic cavity for concealing illegal drugs. Body pushers smuggle illicit drugs by inserting them into rectum or vagina. These cases are either presented to the emergency departments as Body Packer Syndrome or as asymptomatic cases for observation, detained for alleged possession of contraband substances. We report a unique case of an asymptomatic white female who was detained at Mumbai International Airport under suspicion and brought to hospital for observation. X ray and CT scan examination revealed 7 wrapped packets in gastrointestinal track and 1 large packet in vagina. A case of female body packer using multiple modalities of concealment especially in vagina is rare in India so it is becomes imperative to present this case in the light of body packing and body pushing of contraband substances. Copyright © 2017 Elsevier B.V. All rights reserved.

How Much Did Maine's Molocket and Metallak Know about Rapid Climate Change? Did They Utilize Psychological Strategies and Cover Stories to Conceal Their Impact Communities, Observational Sites and Data Collection?

NASA Astrophysics Data System (ADS)

Bates, Tiffany R.; Mc Leod, Roger D.; Mc Leod, David M.

2003-10-01

The Pequakets Molocket (adherent of God La[ngued]oc Christ Cathar Spirit-signal) and Metallak operated in NH and the western border area of ME, during the early 1800s. Molocket requested shelter in South Paris, ME during a powerful thunderstorm. Denied access, she cursed that area. Our interests have led us to recognize that there may be psychological reasons that deception is good strategic procedure for concealing valuable activities associated with impact power groups striving to protect their operating turf. Many sites associated with tradition-respecting Native Americans are quite electromagnetically responsive to climate change. Metallak (mathematician-applied astronomer God Spirit-signal) is purported to have driven off his son over purloined furs; that elder son then operated among the MiKmaw/Micmacs of ME and the Canadian Maritimes. They are purported to make the weather. Information protection and surreptitious data collection may indicate an impact groups concealed interests.

Minority Stress and Same-Sex Relationship Satisfaction: The Role of Concealment Motivation.

PubMed

Pepping, Christopher A; Cronin, Timothy J; Halford, W Kim; Lyons, Anthony

2018-04-30

Most lesbian, gay, and bisexual (LGB) people want a stable, satisfying romantic relationship. Although many of the predictors of relationship outcomes are similar to those of heterosexual couples, same-sex couples face some additional challenges associated with minority stress that also impact upon relationship quality. Here, we investigate the association between minority stressors and relationship quality in a sample of 363 adults (M age = 30.37, SD = 10.78) currently in a same-sex romantic relationship. Internalized homophobia and difficulties accepting one's LGB identity were each negatively associated with relationship satisfaction via heightened concealment motivation. We also examined the protective role of identity affirmation on relationship quality, finding a direct positive relationship between the two variables. Minority stressors were negatively associated with couple relationship satisfaction via heightened concealment motivation. The finding that identity affirmation directly predicted increased couple satisfaction also highlights the important role of protective factors in same-sex couple relationships. © 2018 Family Process Institute.

Audiomagnetotelluric data to characterize the Revett-type copper-silver deposits at Rock Creek in the Cabinet Mountains Wilderness, Montana

USGS Publications Warehouse

Sampson, Jay A.; Rodriguez, Brian D.

2011-01-01

The Revett-type deposits at Rock Creek are part of the concealed stratabound copper-silver deposits located in the Cabinet Mountains Wilderness of Montana. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. Geologic, geochemical, geophysical, and mineral resources data are being evaluated with existing and new mineral deposit models to predict the possibility and probability of undiscovered deposits in covered terranes. To help characterize the size, resistivity, and depth of the mineral deposit concealed beneath thick overburden, a regional southwest-northeast audiomagnetotelluric sounding profile was acquired. Further studies will attempt to determine if induced polarization parameters can be extracted from the magnetotelluric data to determine the size of the mineralized area. The purpose of this report is to release the audiomagnetotelluric sounding data collected along that southwest-northeast profile. No interpretation of the data is included.

Resolution requirements for aero-optical simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mani, Ali; Wang Meng; Moin, Parviz

2008-11-10

Analytical criteria are developed to estimate the error of aero-optical computations due to inadequate spatial resolution of refractive index fields in high Reynolds number flow simulations. The unresolved turbulence structures are assumed to be locally isotropic and at low turbulent Mach number. Based on the Kolmogorov spectrum for the unresolved structures, the computational error of the optical path length is estimated and linked to the resulting error in the computed far-field optical irradiance. It is shown that in the high Reynolds number limit, for a given geometry and Mach number, the spatial resolution required to capture aero-optics within a pre-specifiedmore » error margin does not scale with Reynolds number. In typical aero-optical applications this resolution requirement is much lower than the resolution required for direct numerical simulation, and therefore, a typical large-eddy simulation can capture the aero-optical effects. The analysis is extended to complex turbulent flow simulations in which non-uniform grid spacings are used to better resolve the local turbulence structures. As a demonstration, the analysis is used to estimate the error of aero-optical computation for an optical beam passing through turbulent wake of flow over a cylinder.« less

Task-irrelevant distractors in the delay period interfere selectively with visual short-term memory for spatial locations.

PubMed

Marini, Francesco; Scott, Jerry; Aron, Adam R; Ester, Edward F

2017-07-01

Visual short-term memory (VSTM) enables the representation of information in a readily accessible state. VSTM is typically conceptualized as a form of "active" storage that is resistant to interference or disruption, yet several recent studies have shown that under some circumstances task-irrelevant distractors may indeed disrupt performance. Here, we investigated how task-irrelevant visual distractors affected VSTM by asking whether distractors induce a general loss of remembered information or selectively interfere with memory representations. In a VSTM task, participants recalled the spatial location of a target visual stimulus after a delay in which distractors were presented on 75% of trials. Notably, the distractor's eccentricity always matched the eccentricity of the target, while in the critical conditions the distractor's angular position was shifted either clockwise or counterclockwise relative to the target. We then computed estimates of recall error for both eccentricity and polar angle. A general interference model would predict an effect of distractors on both polar angle and eccentricity errors, while a selective interference model would predict effects of distractors on angle but not on eccentricity errors. Results showed that for stimulus angle there was an increase in the magnitude and variability of recall errors. However, distractors had no effect on estimates of stimulus eccentricity. Our results suggest that distractors selectively interfere with VSTM for spatial locations.

Entanglement renormalization, quantum error correction, and bulk causality

NASA Astrophysics Data System (ADS)

Kim, Isaac H.; Kastoryano, Michael J.

2017-04-01

Entanglement renormalization can be viewed as an encoding circuit for a family of approximate quantum error correcting codes. The logical information becomes progres-sively more well-protected against erasure errors at larger length scales. In particular, an approximate variant of holographic quantum error correcting code emerges at low energy for critical systems. This implies that two operators that are largely separated in scales behave as if they are spatially separated operators, in the sense that they obey a Lieb-Robinson type locality bound under a time evolution generated by a local Hamiltonian.

An empirical understanding of triple collocation evaluation measure

NASA Astrophysics Data System (ADS)

Scipal, Klaus; Doubkova, Marcela; Hegyova, Alena; Dorigo, Wouter; Wagner, Wolfgang

2013-04-01

Triple collocation method is an advanced evaluation method that has been used in the soil moisture field for only about half a decade. The method requires three datasets with an independent error structure that represent an identical phenomenon. The main advantages of the method are that it a) doesn't require a reference dataset that has to be considered to represent the truth, b) limits the effect of random and systematic errors of other two datasets, and c) simultaneously assesses the error of three datasets. The objective of this presentation is to assess the triple collocation error (Tc) of the ASAR Global Mode Surface Soil Moisture (GM SSM 1) km dataset and highlight problems of the method related to its ability to cancel the effect of error of ancillary datasets. In particular, the goal is to a) investigate trends in Tc related to the change in spatial resolution from 5 to 25 km, b) to investigate trends in Tc related to the choice of a hydrological model, and c) to study the relationship between Tc and other absolute evaluation methods (namely RMSE and Error Propagation EP). The triple collocation method is implemented using ASAR GM, AMSR-E, and a model (either AWRA-L, GLDAS-NOAH, or ERA-Interim). First, the significance of the relationship between the three soil moisture datasets was tested that is a prerequisite for the triple collocation method. Second, the trends in Tc related to the choice of the third reference dataset and scale were assessed. For this purpose the triple collocation is repeated replacing AWRA-L with two different globally available model reanalysis dataset operating at different spatial resolution (ERA-Interim and GLDAS-NOAH). Finally, the retrieved results were compared to the results of the RMSE and EP evaluation measures. Our results demonstrate that the Tc method does not eliminate the random and time-variant systematic errors of the second and the third dataset used in the Tc. The possible reasons include the fact a) that the TC method could not fully function with datasets acting at very different spatial resolutions, or b) that the errors were not fully independent as initially assumed.

Evaluation and error apportionment of an ensemble of atmospheric chemistry transport modeling systems: multivariable temporal and spatial breakdown

EPA Science Inventory

Through the comparison of several regional-scale chemistry transport modelling systems that simulate meteorology and air quality over the European and American continents, this study aims at i) apportioning the error to the responsible processes using time-scale analysis, ii) hel...

A Concealed Information Test with multimodal measurement.

PubMed

Ambach, Wolfgang; Bursch, Stephanie; Stark, Rudolf; Vaitl, Dieter

2010-03-01

A Concealed Information Test (CIT) investigates differential physiological responses to deed-related (probe) vs. irrelevant items. The present study focused on the detection of concealed information using simultaneous recordings of autonomic and brain electrical measures. As a secondary issue, verbal and pictorial presentations were compared with respect to their influence on the recorded measures. Thirty-one participants underwent a mock-crime scenario with a combined verbal and pictorial presentation of nine items. The subsequent CIT, designed with respect to event-related potential (ERP) measurement, used a 3-3.5s interstimulus interval. The item presentation modality, i.e. pictures or written words, was varied between subjects; no response was required from the participants. In addition to electroencephalogram (EEG), electrodermal activity (EDA), electrocardiogram (ECG), respiratory activity, and finger plethysmogram were recorded. A significant probe-vs.-irrelevant effect was found for each of the measures. Compared to sole ERP measurement, the combination of ERP and EDA yielded incremental information for detecting concealed information. Although, EDA per se did not reach the predictive value known from studies primarily designed for peripheral physiological measurement. Presentation modality neither influenced the detection accuracy for autonomic measures nor EEG measures; this underpins the equivalence of verbal and pictorial item presentation in a CIT, regardless of the physiological measures recorded. Future studies should further clarify whether the incremental validity observed in the present study reflects a differential sensitivity of ERP and EDA to different sub-processes in a CIT. Copyright 2009 Elsevier B.V. All rights reserved.

[EFFECTIVENESS OF ADVANCED SKIN FLAP AND V-SHAPED VENTRAL INCISION ALONG THE ROOT OF PENILE SHAFT FOR CONCEALED PENIS].

PubMed

Lin, Junshan; Li, Dumiao; Zhang, Jianxing; Wu, Qiang; Xu, Yali; Lin, Li

2015-09-01

To investigate effectiveness of advanced skin flap and V-shaped ventral incision along the root of penile shaft for concealed penis in children. Between July 2007 and January 2015, 121 boys with concealed penis were treated with advanced skin flap and V-shaped ventral incision along the root of penile shaft. The age varied from 18 months to 13 years (mean, 7.2 years). Repair was based on a vertical incision in median raphe, complete degloving of penis and tacking its base to the dermis of the skin. Advanced skin flap and a V-shaped ventral incision along the root of penile shaft were used to cover the penile shaft. The operation time ranged from 60 to 100 minutes (mean, 75 minutes). Disruption of wound occurred in 1 case, and was cured after dressing change; and primary healing of incision was obtained in the others. The follow-up period ranged from 3 months to 7 years (median, 24 months). All patients achieved good to excellent cosmetic results with a low incidence of complications. The results were satisfactory in exposure of penis and prepuce appearance. No obvious scar was observed. The penis had similar appearance to that after prepuce circumcision. A combination of advanced skin flap and V-shaped ventral incision along the root of penile shaft is a simple, safe, and effective procedure for concealed penis with a similar appearance result to the prepuce circumcision.

Concealed Accessory Pathways with a Single Ventricular and Two Discrete Atrial Insertion Sites.

PubMed

Kipp, Ryan T; Abu Sham'a, Raed; Hiroyuki, Ito; Han, Frederick T; Refaat, Marwan; Hsu, Jonathan C; Field, Michael E; Kopp, Douglas E; Marcus, Gregory M; Scheinman, Melvin M; Hoffmayer, Kurt S

2017-03-01

Atrioventricular reciprocating tachycardia (AVRT) utilizing a concealed accessory pathway is common. It is well appreciated that some patients may have multiple accessory pathways with separate atrial and ventricular insertion sites. We present three cases of AVRT utilizing concealed pathways with evidence that each utilizing a single ventricular insertion and two discrete atrial insertion sites. In case one, two discrete atrial insertion sites were mapped in two separate procedures, and only during the second ablation was the Kent potential identified. Ablation of the Kent potential at this site remote from the two atrial insertion sites resulted in the termination of the retrograde conduction in both pathways. Case two presented with supraventricular tachycardia (SVT) with alternating eccentric atrial activation patterns without alteration in the tachycardia cycle length. The two distinct atrial insertion sites during orthodromic AVRT and ventricular pacing were targeted and each of the two atrial insertion sites were successfully mapped and ablated. In case three, retrograde decremental conduction utilizing both atrial insertion sites was identified prior to ablation. After mapping and ablation of the first discrete atrial insertion site, tachycardia persisted utilizing the second atrial insertion site. Only after ablation of the second atrial insertion site was SVT noninducible, and VA conduction was no longer present. Concealed retrograde accessory pathways with discrete atrial insertion sites may have a common ventricular insertion site. Identification and ablation of the ventricular insertion site or the separate discrete atrial insertion sites result in successful treatment. © 2017 Wiley Periodicals, Inc.

Effect of Spatial Titration on Task Performance

ERIC Educational Resources Information Center

Glowacki, Lawrence

1976-01-01

A reinforcement schedule and spatial titration method were used to determine task-reinforcement area separation most preferred and effective in two third-grade boys. Errors in task performance decreased task-reinforcement area separation, while correct responses in task performance increased task-reinforcement area separation. (Author)

Carrier-phase multipath corrections for GPS-based satellite attitude determination

NASA Technical Reports Server (NTRS)

Axelrad, A.; Reichert, P.

2001-01-01

This paper demonstrates the high degree of spatial repeatability of these errors for a spacecraft environment and describes a correction technique, termed the sky map method, which exploits the spatial correlation to correct measurements and improve the accuracy of GPS-based attitude solutions.

Online and offline awareness deficits: Anosognosia for spatial neglect.

PubMed

Chen, Peii; Toglia, Joan

2018-04-12

Anosognosia for spatial neglect (ASN) can be offline or online. Offline ASN is general unawareness of having experienced spatial deficits. Online ASN is an awareness deficit of underestimating spatial difficulties that likely to occur in an upcoming task (anticipatory ASN) or have just occurred during the task (emergent ASN). We explored the relationships among spatial neglect, offline ASN, anticipatory ASN, and emergent ASN. Research Method/Design: Forty-four survivors of stroke answered questionnaires assessing offline and online self-awareness of spatial problems. The online questionnaire was asked immediately before and after each of 4 tests for spatial neglect, including shape cancellation, address and sentence copying, telephone dialing, and indented paragraph reading. Participants were certain they had difficulties in daily spatial tasks (offline awareness), in the task they were about to perform (anticipatory awareness) and had just performed (emergent awareness). Nonetheless, they consistently overestimated their spatial abilities, indicating ASN. Offline and online ASN appeared independent. Online ASN improved after task execution. Neglect severity was not positively correlated with offline ASN. Greater neglect severity correlated with both greater anticipatory and emergent ASN. Regardless of neglect severity, we found task-specific differences in emergent ASN but not in anticipatory ASN. Individuals with spatial neglect acknowledge their spatial difficulty (certainty of error occurrence) but may not necessarily recognize the extent of their difficulty (accuracy of error estimation). Our findings suggest that offline and online ASN are independent. A potential implication from the study is that familiar and challenging tasks may facilitate emergence of self-awareness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Classification of radiological errors in chest radiographs, using support vector machine on the spatial frequency features of false- negative and false-positive regions

NASA Astrophysics Data System (ADS)

Pietrzyk, Mariusz W.; Donovan, Tim; Brennan, Patrick C.; Dix, Alan; Manning, David J.

2011-03-01

Aim: To optimize automated classification of radiological errors during lung nodule detection from chest radiographs (CxR) using a support vector machine (SVM) run on the spatial frequency features extracted from the local background of selected regions. Background: The majority of the unreported pulmonary nodules are visually detected but not recognized; shown by the prolonged dwell time values at false-negative regions. Similarly, overestimated nodule locations are capturing substantial amounts of foveal attention. Spatial frequency properties of selected local backgrounds are correlated with human observer responses either in terms of accuracy in indicating abnormality position or in the precision of visual sampling the medical images. Methods: Seven radiologists participated in the eye tracking experiments conducted under conditions of pulmonary nodule detection from a set of 20 postero-anterior CxR. The most dwelled locations have been identified and subjected to spatial frequency (SF) analysis. The image-based features of selected ROI were extracted with un-decimated Wavelet Packet Transform. An analysis of variance was run to select SF features and a SVM schema was implemented to classify False-Negative and False-Positive from all ROI. Results: A relative high overall accuracy was obtained for each individually developed Wavelet-SVM algorithm, with over 90% average correct ratio for errors recognition from all prolonged dwell locations. Conclusion: The preliminary results show that combined eye-tracking and image-based features can be used for automated detection of radiological error with SVM. The work is still in progress and not all analytical procedures have been completed, which might have an effect on the specificity of the algorithm.

Proximity to natural amenities: A seemingly unrelated hedonic regression model with spatial durbin and spatial error processes

Treesearch

German M. Izon; Michael S. Hand; Daniel W. Mccollum; Jennifer A. Thacher; Robert P. Berrens

2016-01-01

The existing literature suggests that the presence of natural amenities, such as open spaces, can be highly valued and affect economic decisions about where people live and work. This article contributes to previous research by testing this hypothesis using a unique micro-level data set and by examining spatial variations in income levels and housing prices in the...

Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

NASA Astrophysics Data System (ADS)

Chen, J. M.; Chen, X.; Ju, W.

2013-03-01

Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs) for predicting land-atmosphere interactions and carbon-climate feedbacks. In this study, a simple spatial scaling algorithm is developed to correct errors in net primary productivity (NPP) estimates made at a coarse spatial resolution based on sub-pixel information of vegetation heterogeneity and surface topography. An eco-hydrological model BEPS-TerrainLab, which considers both vegetation and topographical effects on the vertical and lateral water flows and the carbon cycle, is used to simulate NPP at 30 m and 1 km resolutions for a 5700 km2 watershed with an elevation range from 518 m to 3767 m in the Qinling Mountain, Shaanxi Province, China. Assuming that the NPP simulated at 30 m resolution represents the reality and that at 1 km resolution is subject to errors due to sub-pixel heterogeneity, a spatial scaling index (SSI) is developed to correct the coarse resolution NPP values pixel by pixel. The agreement between the NPP values at these two resolutions is improved considerably from R2 = 0.782 to R2 = 0.884 after the correction. The mean bias error (MBE) in NPP modeled at the 1 km resolution is reduced from 14.8 g C m-2 yr-1 to 4.8 g C m-2 yr-1 in comparison with NPP modeled at 30 m resolution, where the mean NPP is 668 g C m-2 yr-1. The range of spatial variations of NPP at 30 m resolution is larger than that at 1 km resolution. Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous areas, because of its influence on the lateral water redistribution, affecting water table, soil moisture and plant growth. Other factors including leaf area index (LAI), elevation and aspect have small and additive effects on improving the spatial scaling between these two resolutions.

Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

NASA Astrophysics Data System (ADS)

Chen, J. M.; Chen, X.; Ju, W.

2013-07-01

Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs) for predicting land-atmosphere interactions and carbon-climate feedbacks. In this study, a simple spatial scaling algorithm is developed to correct errors in net primary productivity (NPP) estimates made at a coarse spatial resolution based on sub-pixel information of vegetation heterogeneity and surface topography. An eco-hydrological model BEPS-TerrainLab, which considers both vegetation and topographical effects on the vertical and lateral water flows and the carbon cycle, is used to simulate NPP at 30 m and 1 km resolutions for a 5700 km2 watershed with an elevation range from 518 m to 3767 m in the Qinling Mountain, Shanxi Province, China. Assuming that the NPP simulated at 30 m resolution represents the reality and that at 1 km resolution is subject to errors due to sub-pixel heterogeneity, a spatial scaling index (SSI) is developed to correct the coarse resolution NPP values pixel by pixel. The agreement between the NPP values at these two resolutions is improved considerably from R2 = 0.782 to R2 = 0.884 after the correction. The mean bias error (MBE) in NPP modelled at the 1 km resolution is reduced from 14.8 g C m-2 yr-1 to 4.8 g C m-2 yr-1 in comparison with NPP modelled at 30 m resolution, where the mean NPP is 668 g C m-2 yr-1. The range of spatial variations of NPP at 30 m resolution is larger than that at 1 km resolution. Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous areas, because of its influence on the lateral water redistribution, affecting water table, soil moisture and plant growth. Other factors including leaf area index (LAI) and elevation have small and additive effects on improving the spatial scaling between these two resolutions.

Baseline Error Analysis and Experimental Validation for Height Measurement of Formation Insar Satellite

NASA Astrophysics Data System (ADS)

Gao, X.; Li, T.; Zhang, X.; Geng, X.

2018-04-01

In this paper, we proposed the stochastic model of InSAR height measurement by considering the interferometric geometry of InSAR height measurement. The model directly described the relationship between baseline error and height measurement error. Then the simulation analysis in combination with TanDEM-X parameters was implemented to quantitatively evaluate the influence of baseline error to height measurement. Furthermore, the whole emulation validation of InSAR stochastic model was performed on the basis of SRTM DEM and TanDEM-X parameters. The spatial distribution characteristics and error propagation rule of InSAR height measurement were fully evaluated.

Correction of concealed penis with preservation of the prepuce.

PubMed

Valioulis, I A; Kallergis, I C; Ioannidou, D C

2015-10-01

By definition, congenital concealed penis presents at birth. Children are usually referred to physicians because of parental anxiety caused by their child's penile size. Several surgical procedures have been described to treat this condition, but its correction is still technically challenging. The present study reports a simple surgical approach, which allows preservation of the prepuce. During the last 6 years, 18 children with concealed penis (according to the classification by Maizels et al.) have been treated in the present department (mean age 4.5 years, range 3-12 years). Patients with other conditions that caused buried penis were excluded from the study. The operation was performed through a longitudinal midline ventral incision, which was extended hemi-circumferentially at the penile base. The dysgenetic dartos was identified and its distal part was resected. Dissection of the corpora cavernosa was carried down to the suspensory ligament, which was sectioned. Buck's fascia was fixed to Scarpa's fascia and shaft skin was approximated in the midline. Penoscrotal angle was fashioned by Z-plasty or V-Y plasty. The median follow-up was 24 months (range 8-36). The postoperative edema was mild and resolved within a week. All children had good to excellent outcomes. The median pre-operative to postoperative difference in penile length in the flaccid state was 2.6 cm (range 2.0-3.5). No serious complications or recurrent penile retraction were noted. Recent literature mostly suggests that concealed penis is due to deficient proximal attachments of dysgenetic dartos. Consequences of this include: difficulties in maintaining proper hygiene, balanitis, voiding difficulties with prepuce ballooning and urine spraying, and embarrassment among peers. Surgical treatment for congenital concealed penis is warranted in children aged 3 years or older. The basis of the technique is the perception that in boys with congenital concealed penis, the penile integuments are normal but they have abnormal attachments, and that incision of the skin and dartos will allow the shaft to extend. Furthermore, incisions of the fundiform and suspensory ligaments facilitate this maneuver. With this technique, the blood supply of the penile skin is not interrupted and postoperative lymphedema, a difficult complication to deal with, is prevented. One major advantage is the preservation of the prepuce, giving a normal penile appearance and an excellent cosmetic result. The method proposed here is simple and has no serious complications. It is suggested that this condition be treated in pre-school-aged children in order to prevent psychological impairment. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Tactile Cueing as a Gravitational Substitute for Spatial Navigation During Parabolic Flight

NASA Technical Reports Server (NTRS)

Montgomery, K. L.; Beaton, K. H.; Barba, J. M.; Cackler, J. M.; Son, J. H.; Horsfield, S. P.; Wood, S. J.

2010-01-01

INTRODUCTION: Spatial navigation requires an accurate awareness of orientation in your environment. The purpose of this experiment was to examine how spatial awareness was impaired with changing gravitational cues during parabolic flight, and the extent to which vibrotactile feedback of orientation could be used to help improve performance. METHODS: Six subjects were restrained in a chair tilted relative to the plane floor, and placed at random positions during the start of the microgravity phase. Subjects reported their orientation using verbal reports, and used a hand-held controller to point to a desired target location presented using a virtual reality video mask. This task was repeated with and without constant tactile cueing of "down" direction using a belt of 8 tactors placed around the mid-torso. Control measures were obtained during ground testing using both upright and tilted conditions. RESULTS: Perceptual estimates of orientation and pointing accuracy were impaired during microgravity or during rotation about an upright axis in 1g. The amount of error was proportional to the amount of chair displacement. Perceptual errors were reduced during movement about a tilted axis on earth. CONCLUSIONS: Reduced perceptual errors during tilts in 1g indicate the importance of otolith and somatosensory cues for maintaining spatial awareness. Tactile cueing may improve navigation in operational environments or clinical populations, providing a non-visual non-auditory feedback of orientation or desired direction heading.

[The effect of the new nootropic dipeptide GVS-111 in different functional disorders of the escape reaction].

PubMed

Inozemtsev, A N; Trofimov, S S; Borlikova, G G; Firova, F A; Pragina, L L; Gudasheva, T A; Ostrovskaia, R U; Tushmalova, N A; Voronina, T A

1998-01-01

The authors studied the effect of a new nootropic agent with anxiolytic properties GVS-111 (ethyl ether N-phenylacetyl-L-prolylglycine) on formation of the avoidance reaction (AR) in rats and its functional disorders which were induced by two methods. In one case the stereotype of the relations between the stimulus, reaction and its consequence which developed during the experiment were urgently disturbed: the change of the animal to the other half of the chamber in response to a conditioned stimulus did not lead to its cutting off and prevention of the electropain stimulation for three successive combinations (AR error). In another case the spatial stereotype of the experiment was altered by changing the place of the opening through which the animal avoided the stimulus (spatial remodeling). Intraperitoneal injection of GVS-111 (0.1 mg/kg/day) improved the learning, but the effect differed from experiment to experiment. Along with this, the dipeptide prevented AR disturbance during the error and quickened restoration of the habit in spatial remodeling. It was shown earlier that AR disorders during an error are prevented by anxiolytics and nootropic agents but during spatial remodeling only by nootropic agents. It may be assumed that the positive effect of GSV-111 on AR in functional disorders is due to its nootropic effect.

Quantified pH imaging with hyperpolarized (13) C-bicarbonate.

PubMed

Scholz, David Johannes; Janich, Martin A; Köllisch, Ulrich; Schulte, Rolf F; Ardenkjaer-Larsen, Jan H; Frank, Annette; Haase, Axel; Schwaiger, Markus; Menzel, Marion I

2015-06-01

Because pH plays a crucial role in several diseases, it is desirable to measure pH in vivo noninvasively and in a spatially localized manner. Spatial maps of pH were quantified in vitro, with a focus on method-based errors, and applied in vivo. In vitro and in vivo (13) C mapping were performed for various flip angles for bicarbonate (BiC) and CO2 with spectral-spatial excitation and spiral readout in healthy Lewis rats in five slices. Acute subcutaneous sterile inflammation was induced with Concanavalin A in the right leg of Buffalo rats. pH and proton images were measured 2 h after induction. After optimizing the signal to noise ratio of the hyperpolarized (13) C-bicarbonate, error estimation of the spectral-spatial excited spectrum reveals that the method covers the biologically relevant pH range of 6 to 8 with low pH error (< 0.2). Quantification of pH maps shows negligible impact of the residual bicarbonate signal. pH maps reflect the induction of acute metabolic alkalosis. Inflamed, infected regions exhibit lower pH. Hyperpolarized (13) C-bicarbonate pH mapping was shown to be sensitive in the biologically relevant pH range. The mapping of pH was applied to healthy in vivo organs and interpreted within inflammation and acute metabolic alkalosis models. © 2014 Wiley Periodicals, Inc.

Space-Time Data Fusion

NASA Technical Reports Server (NTRS)

Braverman, Amy; Nguyen, Hai; Olsen, Edward; Cressie, Noel

2011-01-01

Space-time Data Fusion (STDF) is a methodology for combing heterogeneous remote sensing data to optimally estimate the true values of a geophysical field of interest, and obtain uncertainties for those estimates. The input data sets may have different observing characteristics including different footprints, spatial resolutions and fields of view, orbit cycles, biases, and noise characteristics. Despite these differences all observed data can be linked to the underlying field, and therefore the each other, by a statistical model. Differences in footprints and other geometric characteristics are accounted for by parameterizing pixel-level remote sensing observations as spatial integrals of true field values lying within pixel boundaries, plus measurement error. Both spatial and temporal correlations in the true field and in the observations are estimated and incorporated through the use of a space-time random effects (STRE) model. Once the models parameters are estimated, we use it to derive expressions for optimal (minimum mean squared error and unbiased) estimates of the true field at any arbitrary location of interest, computed from the observations. Standard errors of these estimates are also produced, allowing confidence intervals to be constructed. The procedure is carried out on a fine spatial grid to approximate a continuous field. We demonstrate STDF by applying it to the problem of estimating CO2 concentration in the lower-atmosphere using data from the Atmospheric Infrared Sounder (AIRS) and the Japanese Greenhouse Gasses Observing Satellite (GOSAT) over one year for the continental US.

Analysis and correction of gradient nonlinearity bias in apparent diffusion coefficient measurements.

PubMed

Malyarenko, Dariya I; Ross, Brian D; Chenevert, Thomas L

2014-03-01

Gradient nonlinearity of MRI systems leads to spatially dependent b-values and consequently high non-uniformity errors (10-20%) in apparent diffusion coefficient (ADC) measurements over clinically relevant field-of-views. This work seeks practical correction procedure that effectively reduces observed ADC bias for media of arbitrary anisotropy in the fewest measurements. All-inclusive bias analysis considers spatial and time-domain cross-terms for diffusion and imaging gradients. The proposed correction is based on rotation of the gradient nonlinearity tensor into the diffusion gradient frame where spatial bias of b-matrix can be approximated by its Euclidean norm. Correction efficiency of the proposed procedure is numerically evaluated for a range of model diffusion tensor anisotropies and orientations. Spatial dependence of nonlinearity correction terms accounts for the bulk (75-95%) of ADC bias for FA = 0.3-0.9. Residual ADC non-uniformity errors are amplified for anisotropic diffusion. This approximation obviates need for full diffusion tensor measurement and diagonalization to derive a corrected ADC. Practical scenarios are outlined for implementation of the correction on clinical MRI systems. The proposed simplified correction algorithm appears sufficient to control ADC non-uniformity errors in clinical studies using three orthogonal diffusion measurements. The most efficient reduction of ADC bias for anisotropic medium is achieved with non-lab-based diffusion gradients. Copyright © 2013 Wiley Periodicals, Inc.

Analysis and correction of gradient nonlinearity bias in ADC measurements

PubMed Central

Malyarenko, Dariya I.; Ross, Brian D.; Chenevert, Thomas L.

2013-01-01

Purpose Gradient nonlinearity of MRI systems leads to spatially-dependent b-values and consequently high non-uniformity errors (10–20%) in ADC measurements over clinically relevant field-of-views. This work seeks practical correction procedure that effectively reduces observed ADC bias for media of arbitrary anisotropy in the fewest measurements. Methods All-inclusive bias analysis considers spatial and time-domain cross-terms for diffusion and imaging gradients. The proposed correction is based on rotation of the gradient nonlinearity tensor into the diffusion gradient frame where spatial bias of b-matrix can be approximated by its Euclidean norm. Correction efficiency of the proposed procedure is numerically evaluated for a range of model diffusion tensor anisotropies and orientations. Results Spatial dependence of nonlinearity correction terms accounts for the bulk (75–95%) of ADC bias for FA = 0.3–0.9. Residual ADC non-uniformity errors are amplified for anisotropic diffusion. This approximation obviates need for full diffusion tensor measurement and diagonalization to derive a corrected ADC. Practical scenarios are outlined for implementation of the correction on clinical MRI systems. Conclusions The proposed simplified correction algorithm appears sufficient to control ADC non-uniformity errors in clinical studies using three orthogonal diffusion measurements. The most efficient reduction of ADC bias for anisotropic medium is achieved with non-lab-based diffusion gradients. PMID:23794533

Digital spatial data for observed, predicted, and misclassification errors for observations in the training dataset for nitrate and arsenic concentrations in basin-fill aquifers in the Southwest Principal Aquifers study area

USGS Publications Warehouse

McKinney, Tim S.; Anning, David W.

2012-01-01

This product "Digital spatial data for observed, predicted, and misclassification errors for observations in the training dataset for nitrate and arsenic concentrations in basin-fill aquifers in the Southwest Principal Aquifers study area" is a 1:250,000-scale point spatial dataset developed as part of a regional Southwest Principal Aquifers (SWPA) study (Anning and others, 2012). The study examined the vulnerability of basin-fill aquifers in the southwestern United States to nitrate contamination and arsenic enrichment. Statistical models were developed by using the random forest classifier algorithm to predict concentrations of nitrate and arsenic across a model grid that represents local- and basin-scale measures of source, aquifer susceptibility, and geochemical conditions.

Far field and wavefront characterization of a high-power semiconductor laser for free space optical communications

NASA Technical Reports Server (NTRS)

Cornwell, Donald M., Jr.; Saif, Babak N.

1991-01-01

The spatial pointing angle and far field beamwidth of a high-power semiconductor laser are characterized as a function of CW power and also as a function of temperature. The time-averaged spatial pointing angle and spatial lobe width were measured under intensity-modulated conditions. The measured pointing deviations are determined to be well within the pointing requirements of the NASA Laser Communications Transceiver (LCT) program. A computer-controlled Mach-Zehnder phase-shifter interferometer is used to characterize the wavefront quality of the laser. The rms phase error over the entire pupil was measured as a function of CW output power. Time-averaged measurements of the wavefront quality are also made under intensity-modulated conditions. The measured rms phase errors are determined to be well within the wavefront quality requirements of the LCT program.

Comparison Spatial Pattern of Land Surface Temperature with Mono Window Algorithm and Split Window Algorithm: A Case Study in South Tangerang, Indonesia

NASA Astrophysics Data System (ADS)

Bunai, Tasya; Rokhmatuloh; Wibowo, Adi

2018-05-01

In this paper, two methods to retrieve the Land Surface Temperature (LST) from thermal infrared data supplied by band 10 and 11 of the Thermal Infrared Sensor (TIRS) onboard the Landsat 8 is compared. The first is mono window algorithm developed by Qin et al. and the second is split window algorithm by Rozenstein et al. The purpose of this study is to perform the spatial distribution of land surface temperature, as well as to determine more accurate algorithm for retrieving land surface temperature by calculated root mean square error (RMSE). Finally, we present comparison the spatial distribution of land surface temperature by both of algorithm, and more accurate algorithm is split window algorithm refers to the root mean square error (RMSE) is 7.69° C.

Evaluation and testing of image quality of the Space Solar Extreme Ultraviolet Telescope

NASA Astrophysics Data System (ADS)

Peng, Jilong; Yi, Zhong; Zhou, Shuhong; Yu, Qian; Hou, Yinlong; Wang, Shanshan

2018-01-01

For the space solar extreme ultraviolet telescope, the star point test can not be performed in the x-ray band (19.5nm band) as there is not light source of bright enough. In this paper, the point spread function of the optical system is calculated to evaluate the imaging performance of the telescope system. Combined with the actual processing surface error, such as small grinding head processing and magnetorheological processing, the optical design software Zemax and data analysis software Matlab are used to directly calculate the system point spread function of the space solar extreme ultraviolet telescope. Matlab codes are programmed to generate the required surface error grid data. These surface error data is loaded to the specified surface of the telescope system by using the communication technique of DDE (Dynamic Data Exchange), which is used to connect Zemax and Matlab. As the different processing methods will lead to surface error with different size, distribution and spatial frequency, the impact of imaging is also different. Therefore, the characteristics of the surface error of different machining methods are studied. Combining with its position in the optical system and simulation its influence on the image quality, it is of great significance to reasonably choose the processing technology. Additionally, we have also analyzed the relationship between the surface error and the image quality evaluation. In order to ensure the final processing of the mirror to meet the requirements of the image quality, we should choose one or several methods to evaluate the surface error according to the different spatial frequency characteristics of the surface error.

An Efficient Silent Data Corruption Detection Method with Error-Feedback Control and Even Sampling for HPC Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di, Sheng; Berrocal, Eduardo; Cappello, Franck

The silent data corruption (SDC) problem is attracting more and more attentions because it is expected to have a great impact on exascale HPC applications. SDC faults are hazardous in that they pass unnoticed by hardware and can lead to wrong computation results. In this work, we formulate SDC detection as a runtime one-step-ahead prediction method, leveraging multiple linear prediction methods in order to improve the detection results. The contributions are twofold: (1) we propose an error feedback control model that can reduce the prediction errors for different linear prediction methods, and (2) we propose a spatial-data-based even-sampling method tomore » minimize the detection overheads (including memory and computation cost). We implement our algorithms in the fault tolerance interface, a fault tolerance library with multiple checkpoint levels, such that users can conveniently protect their HPC applications against both SDC errors and fail-stop errors. We evaluate our approach by using large-scale traces from well-known, large-scale HPC applications, as well as by running those HPC applications on a real cluster environment. Experiments show that our error feedback control model can improve detection sensitivity by 34-189% for bit-flip memory errors injected with the bit positions in the range [20,30], without any degradation on detection accuracy. Furthermore, memory size can be reduced by 33% with our spatial-data even-sampling method, with only a slight and graceful degradation in the detection sensitivity.« less

Phase measurement error in summation of electron holography series.

PubMed

McLeod, Robert A; Bergen, Michael; Malac, Marek

2014-06-01

Off-axis electron holography is a method for the transmission electron microscope (TEM) that measures the electric and magnetic properties of a specimen. The electrostatic and magnetic potentials modulate the electron wavefront phase. The error in measurement of the phase therefore determines the smallest observable changes in electric and magnetic properties. Here we explore the summation of a hologram series to reduce the phase error and thereby improve the sensitivity of electron holography. Summation of hologram series requires independent registration and correction of image drift and phase wavefront drift, the consequences of which are discussed. Optimization of the electro-optical configuration of the TEM for the double biprism configuration is examined. An analytical model of image and phase drift, composed of a combination of linear drift and Brownian random-walk, is derived and experimentally verified. The accuracy of image registration via cross-correlation and phase registration is characterized by simulated hologram series. The model of series summation errors allows the optimization of phase error as a function of exposure time and fringe carrier frequency for a target spatial resolution. An experimental example of hologram series summation is provided on WS2 fullerenes. A metric is provided to measure the object phase error from experimental results and compared to analytical predictions. The ultimate experimental object root-mean-square phase error is 0.006 rad (2π/1050) at a spatial resolution less than 0.615 nm and a total exposure time of 900 s. The ultimate phase error in vacuum adjacent to the specimen is 0.0037 rad (2π/1700). The analytical prediction of phase error differs with the experimental metrics by +7% inside the object and -5% in the vacuum, indicating that the model can provide reliable quantitative predictions. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

COSMETIC CAMOUFLAGE IN VITILIGO

PubMed Central

Sarveswari, K N

2010-01-01

Vitiligo is not a life–threatening nor a contagious disease. But the disfigurement of vitiligo can be devastating to its sufferers, especially dark-skinned individuals. Available treatment options are disappointing and sufferers often use various forms of camouflage. Remedial cosmetic cover creams help conceal the blemish of vitiligo at least temporarily. A high concentration of pigment is incorporated into water–free or anhydrous foundations to give a color that matches the patient’s skin, thereby concealing vitiligo patches. The article highlights the content and technique of application of these creams. PMID:21063508

Methods to achieve accurate projection of regional and global raster databases

USGS Publications Warehouse

Usery, E.L.; Seong, J.C.; Steinwand, D.R.; Finn, M.P.

2002-01-01

This research aims at building a decision support system (DSS) for selecting an optimum projection considering various factors, such as pixel size, areal extent, number of categories, spatial pattern of categories, resampling methods, and error correction methods. Specifically, this research will investigate three goals theoretically and empirically and, using the already developed empirical base of knowledge with these results, develop an expert system for map projection of raster data for regional and global database modeling. The three theoretical goals are as follows: (1) The development of a dynamic projection that adjusts projection formulas for latitude on the basis of raster cell size to maintain equal-sized cells. (2) The investigation of the relationships between the raster representation and the distortion of features, number of categories, and spatial pattern. (3) The development of an error correction and resampling procedure that is based on error analysis of raster projection.

Dynamic changes in brain activity during prism adaptation.

PubMed

Luauté, Jacques; Schwartz, Sophie; Rossetti, Yves; Spiridon, Mona; Rode, Gilles; Boisson, Dominique; Vuilleumier, Patrik

2009-01-07

Prism adaptation does not only induce short-term sensorimotor plasticity, but also longer-term reorganization in the neural representation of space. We used event-related fMRI to study dynamic changes in brain activity during both early and prolonged exposure to visual prisms. Participants performed a pointing task before, during, and after prism exposure. Measures of trial-by-trial pointing errors and corrections allowed parametric analyses of brain activity as a function of performance. We show that during the earliest phase of prism exposure, anterior intraparietal sulcus was primarily implicated in error detection, whereas parieto-occipital sulcus was implicated in error correction. Cerebellum activity showed progressive increases during prism exposure, in accordance with a key role for spatial realignment. This time course further suggests that the cerebellum might promote neural changes in superior temporal cortex, which was selectively activated during the later phase of prism exposure and could mediate the effects of prism adaptation on cognitive spatial representations.

Improving demodulation accuracy of low-coherence interferometer against spatial-frequency nonlinearity

NASA Astrophysics Data System (ADS)

Wang, Shuang; Liu, Tiegen; Jiang, Junfeng; Liu, Kun; Yin, Jinde; Wu, Fan; Zhao, Bofu; Xue, Lei; Mei, Yunqiao; Wu, Zhenhai

2013-12-01

We present an effective method to compensate the spatial-frequency nonlinearity for polarized low-coherence interferometer with location-dependent dispersion element. Through the use of location-dependent dispersive characteristics, the method establishes the exact relationship between wave number and discrete Fourier transform (DFT) serial number. The jump errors in traditional absolute phase algorithm are also avoided with nonlinearity compensation. We carried out experiments with an optical fiber Fabry-Perot (F-P) pressure sensing system to verify the effectiveness. The demodulated error is less than 0.139kPa in the range of 170kPa when using our nonlinearity compensation process in the demodulation.

A framework for simulating map error in ecosystem models

Treesearch

Sean P. Healey; Shawn P. Urbanski; Paul L. Patterson; Chris Garrard

2014-01-01

The temporal depth and spatial breadth of observations from platforms such as Landsat provide unique perspective on ecosystem dynamics, but the integration of these observations into formal decision support will rely upon improved uncertainty accounting. Monte Carlo (MC) simulations offer a practical, empirical method of accounting for potential map errors in broader...

Handwriting Error Patterns of Children with Mild Motor Difficulties.

ERIC Educational Resources Information Center

Malloy-Miller, Theresa; And Others

1995-01-01

A test of handwriting legibility and 6 perceptual-motor tests were completed by 66 children ages 7-12. Among handwriting error patterns, execution was associated with visual-motor skill and sensory discrimination, aiming with visual-motor and fine-motor skills. The visual-spatial factor had no significant association with perceptual-motor…

Errors in Representing Regional Acid Deposition with Spatially Sparse Monitoring: Case Studies of the Eastern US Using Model Predictions

EPA Science Inventory

The current study uses case studies of model-estimated regional precipitation and wet ion deposition to estimate errors in corresponding regional values derived from the means of site-specific values within regions of interest located in the eastern US. The mean of model-estimate...

Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters

NASA Technical Reports Server (NTRS)

Strangman, Gary; Franceschini, Maria Angela; Boas, David A.; Sutton, J. P. (Principal Investigator)

2003-01-01

Near-infrared spectroscopy (NIRS) can be used to noninvasively measure changes in the concentrations of oxy- and deoxyhemoglobin in tissue. We have previously shown that while global changes can be reliably measured, focal changes can produce erroneous estimates of concentration changes (NeuroImage 13 (2001), 76). Here, we describe four separate sources for systematic error in the calculation of focal hemoglobin changes from NIRS data and use experimental methods and Monte Carlo simulations to examine the importance and mitigation methods of each. The sources of error are: (1). the absolute magnitudes and relative differences in pathlength factors as a function of wavelength, (2). the location and spatial extent of the absorption change with respect to the optical probe, (3). possible differences in the spatial distribution of hemoglobin species, and (4). the potential for simultaneous monitoring of multiple regions of activation. We found wavelength selection and optode placement to be important variables in minimizing such errors, and our findings indicate that appropriate experimental procedures could reduce each of these errors to a small fraction (<10%) of the observed concentration changes.

Design Considerations of Polishing Lap for Computer-Controlled Cylindrical Polishing Process

NASA Technical Reports Server (NTRS)

Khan, Gufran S.; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian

2010-01-01

The future X-ray observatory missions, such as International X-ray Observatory, require grazing incidence replicated optics of extremely large collecting area (3 m2) in combination with angular resolution of less than 5 arcsec half-power diameter. The resolution of a mirror shell depends ultimately on the quality of the cylindrical mandrels from which they are being replicated. Mid-spatial-frequency axial figure error is a dominant contributor in the error budget of the mandrel. This paper presents our efforts to develop a deterministic cylindrical polishing process in order to keep the mid-spatial-frequency axial figure errors to a minimum. Simulation studies have been performed to optimize the operational parameters as well as the polishing lap configuration. Furthermore, depending upon the surface error profile, a model for localized polishing based on dwell time approach is developed. Using the inputs from the mathematical model, a mandrel, having conical approximated Wolter-1 geometry, has been polished on a newly developed computer-controlled cylindrical polishing machine. We report our first experimental results and discuss plans for further improvements in the polishing process.

Measuring Two Decades of Ice Mass Loss using GRACE and SLR

NASA Astrophysics Data System (ADS)

Bonin, J. A.; Chambers, D. P.

2016-12-01

We use Satellite Laser Ranging (SLR) to extend the time series of ice mass change back in time to 1994. The SLR series is of far lesser spatial resolution than GRACE, so we apply a constrained inversion technique to better localize the signal. We approximate the likely errors due to SLR's measurement errors combined with the inversion errors from using a low-resolution series, then estimate the interannual mass change over Greenland and Antarctica.

Optimizing dynamic downscaling in one-way nesting using a regional ocean model

NASA Astrophysics Data System (ADS)

Pham, Van Sy; Hwang, Jin Hwan; Ku, Hyeyun

2016-10-01

Dynamical downscaling with nested regional oceanographic models has been demonstrated to be an effective approach for both operationally forecasted sea weather on regional scales and projections of future climate change and its impact on the ocean. However, when nesting procedures are carried out in dynamic downscaling from a larger-scale model or set of observations to a smaller scale, errors are unavoidable due to the differences in grid sizes and updating intervals. The present work assesses the impact of errors produced by nesting procedures on the downscaled results from Ocean Regional Circulation Models (ORCMs). Errors are identified and evaluated based on their sources and characteristics by employing the Big-Brother Experiment (BBE). The BBE uses the same model to produce both nesting and nested simulations; so it addresses those error sources separately (i.e., without combining the contributions of errors from different sources). Here, we focus on discussing errors resulting from the spatial grids' differences, the updating times and the domain sizes. After the BBE was separately run for diverse cases, a Taylor diagram was used to analyze the results and recommend an optimal combination of grid size, updating period and domain sizes. Finally, suggested setups for the downscaling were evaluated by examining the spatial correlations of variables and the relative magnitudes of variances between the nested model and the original data.

Optimization of spatial frequency domain imaging technique for estimating optical properties of food and biological materials

USDA-ARS?s Scientific Manuscript database

Spatial frequency domain imaging technique has recently been developed for determination of the optical properties of food and biological materials. However, accurate estimation of the optical property parameters by the technique is challenging due to measurement errors associated with signal acquis...

Space Station Human Factors Research Review. Volume 4: Inhouse Advanced Development and Research

NASA Technical Reports Server (NTRS)

Tanner, Trieve (Editor); Clearwater, Yvonne A. (Editor); Cohen, Marc M. (Editor)

1988-01-01

A variety of human factors studies related to space station design are presented. Subjects include proximity operations and window design, spatial perceptual issues regarding displays, image management, workload research, spatial cognition, virtual interface, fault diagnosis in orbital refueling, and error tolerance and procedure aids.

Categorical Biases in Spatial Memory: The Role of Certainty

ERIC Educational Resources Information Center

Holden, Mark P.; Newcombe, Nora S.; Shipley, Thomas F.

2015-01-01

Memories for spatial locations often show systematic errors toward the central value of the surrounding region. The Category Adjustment (CA) model suggests that this bias is due to a Bayesian combination of categorical and metric information, which offers an optimal solution under conditions of uncertainty (Huttenlocher, Hedges, & Duncan,…

What do results from coordinate-based meta-analyses tell us?

PubMed

Albajes-Eizagirre, Anton; Radua, Joaquim

2018-08-01

Coordinate-based meta-analyses (CBMA) methods, such as Activation Likelihood Estimation (ALE) and Seed-based d Mapping (SDM), have become an invaluable tool for summarizing the findings of voxel-based neuroimaging studies. However, the progressive sophistication of these methods may have concealed two particularities of their statistical tests. Common univariate voxelwise tests (such as the t/z-tests used in SPM and FSL) detect voxels that activate, or voxels that show differences between groups. Conversely, the tests conducted in CBMA test for "spatial convergence" of findings, i.e., they detect regions where studies report "more peaks than in most regions", regions that activate "more than most regions do", or regions that show "larger differences between groups than most regions do". The first particularity is that these tests rely on two spatial assumptions (voxels are independent and have the same probability to have a "false" peak), whose violation may make their results either conservative or liberal, though fortunately current versions of ALE, SDM and some other methods consider these assumptions. The second particularity is that the use of these tests involves an important paradox: the statistical power to detect a given effect is higher if there are no other effects in the brain, whereas lower in presence of multiple effects. Copyright © 2018 Elsevier Inc. All rights reserved.

Gamma-resonance Contraband Detection using a high current tandem accelerator

NASA Astrophysics Data System (ADS)

Milton, B. F.; Beis, J.; Dale, D.; Debiak, T.; Kamykowski, E.; Melnychuk, S.; Rathke, J.; Rogers, J.; Ruegg, R.; Sredniawski, J.

1999-04-01

TRIUMF and Northrop Grumman have developed a new system for the detection of concealed explosives and drugs. This Contraband Detection System (CDS) is based on the resonant absorption by 14N of gammas produced using 13C(p,γ)14N. The chosen reaction uses protons at 1.75 MeV and the gammas have an energy of 9.17 MeV. By measuring both the resonant and the non-resonant absorption using detectors with good spatial resolution, and applying standard tomographic techniques, we are able to produce 3D images of both the nitrogen partial density and the total density. The images together may be utilized with considerable confidence to determine if small amounts of nitrogen based explosives, heroin or cocaine are present in the interrogated containers. Practical Gamma Resonant Absorption (GRA) scanning requires an intense source of protons. However this proton source must also be very stable, have low energy spread, and have good spatial definition. These demands suggested a tandem as the accelerator of choice. We have therefore constructed a 2 MeV H- tandem optimized for high current (10 mA) operation, while minimizing the overall size of the accelerator. This has required several special innovations which will be presented in the paper. We will also present initial commissioning results.

Becoming a high-fidelity - super - imitator: what are the contributions of social and individual learning?

PubMed

Subiaul, Francys; Patterson, Eric M; Schilder, Brian; Renner, Elizabeth; Barr, Rachel

2015-11-01

In contrast to other primates, human children's imitation performance goes from low to high fidelity soon after infancy. Are such changes associated with the development of other forms of learning? We addressed this question by testing 215 children (26-59 months) on two social conditions (imitation, emulation) - involving a demonstration - and two asocial conditions (trial-and-error, recall) - involving individual learning - using two touchscreen tasks. The tasks required responding to either three different pictures in a specific picture order (Cognitive: Airplane→Ball→Cow) or three identical pictures in a specific spatial order (Motor-Spatial: Up→Down→Right). There were age-related improvements across all conditions and imitation, emulation and recall performance were significantly better than trial-and-error learning. Generalized linear models demonstrated that motor-spatial imitation fidelity was associated with age and motor-spatial emulation performance, but cognitive imitation fidelity was only associated with age. While this study provides evidence for multiple imitation mechanisms, the development of one of those mechanisms - motor-spatial imitation - may be bootstrapped by the development of another social learning skill - motor-spatial emulation. Together, these findings provide important clues about the development of imitation, which is arguably a distinctive feature of the human species. © 2014 John Wiley & Sons Ltd.