Interference-free SDMA for FBMC-OQAM
NASA Astrophysics Data System (ADS)
Horlin, François; Fickers, Jessica; Deleu, Thibault; Louveaux, Jérome
2013-12-01
Filter-bank multi-carrier (FBMC) modulations have recently been considered for the emerging wireless communication systems as a means to improve the utilization of the physical resources and the robustness to channel time variations. FBMC divides the overall frequency channel in a set of subchannels of bandwidth proportionally decreasing with the number of subchannels. If the number of subchannels is high enough, the bandwidth of each subchannel is small enough to assume that it is approximately flat. On the other hand, space-division multiple access (SDMA) is a recognized technique to support multiple access in the downlink of a multi-user system. The user signals are precoded at the base station equipped with multiple antennas to separate the users in the spatial domain. The application of SDMA to FBMC is unfortunately difficult when the channel is too frequency selective (or when the number of subchannels to too small) to assume flat subchannels. In that case, the system suffers from inter-symbol and inter-subchannel interference, besides the multi-user interference inherent to SDMA. State-of-the art solutions simply neglect the inter-symbol/subchannel interference. This article proposes a new SDMA precoder for FBMC capable of mitigating the three sources of interference. It is constructed per subchannel in order to keep an acceptable complexity and has the structure of a filter applied on each subchannel and its neighbors at twice the symbol rate. Numerical results demonstrate that the precoder can get rid of all the interference present in the system and benefit therefore from the diversity and power gains achievable with multiple antenna systems.
Exploitation of Multi-beam Directional Antennas for a Wireless TDMA/FDD MAC
NASA Astrophysics Data System (ADS)
Atmaca, Sedat; Ceken, Celal; Erturk, Ismail
2008-05-01
The effects of the multi-beam directional antennas on the performance of a new wireless TDMA/FDD MAC system are presented. Directional antennas intrinsically enable development of the SDMA systems and allow transmitting and receiving signals simultaneously at the same time slot. Employing a dynamic slot allocation table at a base station with 4 or 8 sector directional antennas and holding the wireless terminals' location information, a new SDMA/TDMA/FDD frame structure has been developed for wireless communications. The simulation studies realized using OPNET Modeler show that the proposed SDMA/TDMA/FDD system has substantially increased the traditional TDMA/FDD system capacity and provides 1.37 to 4 times better mean delay results when the number of users is increased from 4 to 32 under the same load in the wireless network models.
Dahlem, D P; Neiger, R; Schweighauser, A; Francey, T; Yerramilli, M; Obare, E; Steinbach, S M L
2017-05-01
Symmetric dimethylarginine (SDMA) is considered a biomarker for early detection of renal dysfunction in human patients with acute kidney injury (AKI). At present, no studies exist analyzing the relevance of SDMA in dogs with AKI. SDMA would correctly identify dogs with renal disease but would not be able to differentiate between AKI and CKD. Eighteen healthy control dogs, 48 dogs with AKI, and 29 dogs with CKD. Prospective study. Dogs with kidney disease were categorized as having AKI or CKD according to the history, clinical signs, laboratory findings, and results of diagnostic imaging. Plasma SDMA concentration was measured by IDEXX Laboratories. SDMA/creatinine ratio was calculated in dogs with AKI or CKD. Median SDMA concentrations were 8.5 μg/dL (6-12 μg/dL), 39.5 μg/dL (8->100 μg/dL), and 35 μg/dL (12->100 μg/dL), in healthy, AKI, and CKD, respectively. SDMA concentrations were significantly higher in dogs with AKI (P < .0001) or CKD (P < .0001) in comparison with healthy dogs. Median SDMA/creatinine ratio in dogs with AKI and CKD was 6.5 (1.7-20.9) and 10 (2.4-33.9) (P = .0004), respectively. Although there was overlap of the SDMA/creatinine ratio in dogs with AKI or CKD, it was significantly higher in dogs with CKD compared to dogs with AKI (P = .0004). In this population, SDMA was suitable for identifying dogs affected by AKI or CKD, but could not differentiate between them. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Dimitroulas, Theodoros; Sandoo, Aamer; Hodson, James; Smith, Jacqueline P; Kitas, George D
2016-07-01
To examine associations between asymmetric (ADMA), symmetric dimethylarginine (SDMA) and ADMA:SDMA ratio with assessments of endothelial function and coronary artery perfusion in RA patients. ADMA and SDMA levels were measured in 197 RA individuals [144 (77.4%) females, median age: 66 years (quartiles: 59-73)]. Patients underwent assessments of microvascular endothelium-dependent and endothelium-independent function, macrovascular endothelium-dependent and endothelium-independent function and vascular morphology (pulse wave analysis, carotid intima-media thickness (cIMT), and carotid plaque). Coronary perfusion was assessed by subendocardial viability ratio (SEVR). SEVR correlated with SDMA (r = 0.172, p = 0.026) and ADMA:SDMA (r = -0.160, p = 0.041) in univariable analysis, but not in multivariable analysis accounting for confounding factors. Neither ADMA:SDMA ratio nor SDMA were significantly correlated with microvascular or macrovascular endothelial function, or with arterial stiffness and cIMT. Within subgroup of patients (n = 26) with high inflammatory markers, a post-hoc analysis showed that SDMA and the ADMA:SDMA ratio were significantly associated with endothelium-dependent microvascular function in univariable analysis, with Pearson's r correlation coefficients of -0.440 (p = 0.031) and 0.511 (p = 0.011), respectively. Similar finding were established between ADMA:SDMA ratio and arterial stiffness in univariable analysis, with Pearson's r of 0.493, (p = 0.024). Dimethylarginines were not found to be significantly associated with several assessments of vascular function and morphology in patients with RA, however, post-hoc analysis indicates that there may be associations in patients with raised inflammatory markers. Our results suggest that dysregulated NO metabolism may not be the sole mechanism for the development of preclinical atherosclerosis in RA.
Relationship between lean body mass and serum renal biomarkers in healthy dogs.
Hall, Jean A; Yerramilli, Maha; Obare, Edward; Yerramilli, Murthy; Melendez, Lynda D; Jewell, Dennis E
2015-01-01
Symmetric dimethylarginine (SDMA) is an accurate and precise biomarker for estimating glomerular filtration rate (GFR) in humans and cats. Serum creatinine (sCr) also correlates with GFR, but has limitations as a biomarker of renal function because nonrenal factors can influence its concentration. Differences in lean body mass (LBM) influence sCr, but not serum SDMA concentrations. Forty-one healthy Beagles, mean age 9.9 years (range: 3.1-14.8 years), were studied over a 6 month period. Serum biomarkers of renal function were measured prospectively at baseline, and 1, 3, and 6 months. SDMA concentrations were measured by liquid chromatography-mass spectroscopy and sCr concentrations by enzymatic colorimetry. Body composition was determined by dual energy x-ray absorptiometry. LBM (P < .001) and age (P = .006) were significant explanatory variables for sCr concentration (R(2) = 0.38), but not SDMA concentration. Time on food was the only significant explanatory variable for SDMA concentration (R(2) = 0.49). SDMA concentrations decreased across time (P < .001). LBM was affected by sex (males > females; P = .02). Mature adult dogs (<8 years) had greater LBM compared with geriatric dogs (≥8 years; P < .001). sCr concentrations, but not SDMA concentrations, are influenced by LBM, which limits sCr utility as a biomarker for monitoring renal function in dogs with decreased LBM. Reductions in LBM can lower sCr concentration and overestimate GFR. SDMA concentrations, but not sCr concentrations were influenced by time on food. SDMA could have clinical advantages over sCr in monitoring response to nutritional interventions. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Serum concentrations of symmetric dimethylarginine and creatinine in cats with kidney stones.
Hall, Jean A; Yerramilli, Maha; Obare, Edward; Li, Jun; Yerramilli, Murthy; Jewell, Dennis E
2017-01-01
Serum concentrations of symmetric dimethylarginine (SDMA) correlate with renal function in cats and SDMA has been shown to be a more reliable and earlier marker for chronic kidney disease (CKD) compared with serum creatinine (Cr). Calcium oxalate uroliths tend to develop in mid-to-older aged cats and kidney stones may cause a reduction in renal function with increased SDMA, but normal serum Cr. The purpose of this retrospective study was to determine if cats with kidney stones had increased serum SDMA concentrations, and whether SDMA increased earlier than serum creatinine concentrations. Cats in the colony with kidney stones diagnosed between August 2010 and December 2015 (n = 43) were compared with healthy geriatric cats (n = 21) without kidney stones. Serum SDMA concentrations were determined by liquid chromatography-mass spectrometry and serum Cr concentrations were determined by enzymatic colorimetry. Cats with kidney stones were diagnosed antemortem by radiographic imaging (n = 12) or by postmortem necropsy (n = 31). Retrospectively, serum SDMA was found to be increased above the upper reference limit in 39 of 43 cats with kidney stones. Serum Cr was increased above the upper reference limit in 18 of 43 cats; 6 of these 18 cats had terminal azotemia only. The mean time that serum SDMA was increased before serum Cr was increased was 26.9 months (range 0 to 60 months). Kidney stones were composed of calcium oxalate in 30 of 34 cats. The lifespan for cats with kidney stones (mean, 12.5 years; range, 6.1 to 18.1 years) was shorter (P < 0.001) than for control cats (mean, 15.2 years; range, 13.0 to 17.2 years), suggesting that non-obstructive kidney stones have an effect on mortality rate or rate of CKD progression. In conclusion, if SDMA concentrations are elevated in mid-to-older aged cats, further imaging studies are warranted to check for the presence of kidney stones.
Serum concentrations of symmetric dimethylarginine and creatinine in cats with kidney stones
Hall, Jean A.; Yerramilli, Maha; Obare, Edward; Li, Jun; Yerramilli, Murthy; Jewell, Dennis E.
2017-01-01
Serum concentrations of symmetric dimethylarginine (SDMA) correlate with renal function in cats and SDMA has been shown to be a more reliable and earlier marker for chronic kidney disease (CKD) compared with serum creatinine (Cr). Calcium oxalate uroliths tend to develop in mid-to-older aged cats and kidney stones may cause a reduction in renal function with increased SDMA, but normal serum Cr. The purpose of this retrospective study was to determine if cats with kidney stones had increased serum SDMA concentrations, and whether SDMA increased earlier than serum creatinine concentrations. Cats in the colony with kidney stones diagnosed between August 2010 and December 2015 (n = 43) were compared with healthy geriatric cats (n = 21) without kidney stones. Serum SDMA concentrations were determined by liquid chromatography-mass spectrometry and serum Cr concentrations were determined by enzymatic colorimetry. Cats with kidney stones were diagnosed antemortem by radiographic imaging (n = 12) or by postmortem necropsy (n = 31). Retrospectively, serum SDMA was found to be increased above the upper reference limit in 39 of 43 cats with kidney stones. Serum Cr was increased above the upper reference limit in 18 of 43 cats; 6 of these 18 cats had terminal azotemia only. The mean time that serum SDMA was increased before serum Cr was increased was 26.9 months (range 0 to 60 months). Kidney stones were composed of calcium oxalate in 30 of 34 cats. The lifespan for cats with kidney stones (mean, 12.5 years; range, 6.1 to 18.1 years) was shorter (P < 0.001) than for control cats (mean, 15.2 years; range, 13.0 to 17.2 years), suggesting that non-obstructive kidney stones have an effect on mortality rate or rate of CKD progression. In conclusion, if SDMA concentrations are elevated in mid-to-older aged cats, further imaging studies are warranted to check for the presence of kidney stones. PMID:28384169
Memon, Lidija; Spasojevic-Kalimanovska, Vesna; Bogavac-Stanojevic, Natasa; Kotur-Stevuljevic, Jelena; Simic-Ogrizovic, Sanja; Giga, Vojislav; Dopsaj, Violeta; Jelic-Ivanovic, Zorana; Spasic, Slavica
2013-01-01
The study was designed to evaluate associations between symmetric dimethylarginine (SDMA), inflammation, and superoxide anion (O2∙-) with endothelial function and to determine their potential for screening of endothelial dysfunction in patients with chronic kidney disease (CKD) and renal transplant (RT) recipients. We included 64 CKD and 52 RT patients. Patients were stratified according to brachial artery flow-mediated dilation (FMD). Logistic regression analysis showed that high SDMA and high sensitive C-reactive protein (hs-CRP) were associated with impaired FMD in CKD and RT patients, after adjustment for glomerular filtration rate. The ability of inflammation, SDMA, and O2∙- to detect impaired FMD was investigated by receiving operative characteristic analysis. Hs-CRP (area under the curves (AUC) = 0.754, P < 0.001), IL-6 (AUC = 0.699, P = 0.002), and SDMA (AUC = 0.689, P = 0.007) had the highest ability to detect impaired FMD. SDMA in combination with inflammatory parameters and/or O2∙- had better screening performance than SDMA alone. Our results indicate a strong predictable association between hs-CRP, SDMA, and endothelial dysfunction in CKD patients and RT recipients. The individual marker that showed the strongest discriminative ability for endothelial dysfunction is hs-CRP, but its usefulness as a discriminatory marker for efficient diagnosis of endothelial dysfunction should be examined in prospective studies.
Structural Basis for Methylarginine-dependent Recognition of Aubergine by Tudor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, H.; Wang, J; Huang, Y
2010-01-01
Piwi proteins are modified by symmetric dimethylation of arginine (sDMA), and the methylarginine-dependent interaction with Tudor domain proteins is critical for their functions in germline development. Cocrystal structures of an extended Tudor domain (eTud) of Drosophila Tudor with methylated peptides of Aubergine, a Piwi family protein, reveal that sDMA is recognized by an asparagine-gated aromatic cage. Furthermore, the unexpected Tudor-SN/p100 fold of eTud is important for sensing the position of sDMA. The structural information provides mechanistic insights into sDMA-dependent Piwi-Tudor interaction, and the recognition of sDMA by Tudor domains in general.
Jaźwińska-Kozuba, Aleksandra; Martens-Lobenhoffer, Jens; Surdacki, Andrzej; Kruszelnicka, Olga; Rycaj, Jarosław; Godula-Stuglik, Urszula; Bode-Böger, Stefanie M
2012-11-21
The structural isomer of asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), is eliminated almost entirely by urinary excretion and considered a sensitive index of glomerular filtration rate (GFR). However, reports on this relationship in healthy subjects younger than 18 years of age are rare. Therefore, our aim was to investigate relations between endogenous dimethylarginines and renal function indices in healthy children and adolescents. We studied 40 subjects aged 3–18 years free of coexistent diseases or subclinical carotid atherosclerosis. A serum creatinine-derived estimated GFR (eGFR) was calculated by the revised bedside Schwartz equation. L-arginine, ADMA and SDMA were measured by liquid chromatography-tandem mass spectrometry. Mean eGFR was 122 ± 22 (SD) mL/min per 1.73 m2. Creatinine and eGFR exhibited closer correlations with the SDMA/ADMA ratio (r = 0.64, p < 0.0001; r = −0.63, p < 0.0001, respectively) than with SDMA (r = 0.31, p = 0.05; r = −0.35, p = 0.03). Neither creatinine nor eGFR correlated with ADMA or L-arginine. Adjustment for age or height only slightly attenuated the associations between the SDMA/ADMA ratio and eGFR or creatinine. Our findings suggest the superiority of the SDMA/ADMA ratio over SDMA as a renal function index in healthy children. Thus, further studies are warranted to verify our preliminary results in a larger group of subjects below 18 years of age.
Giga, Vojislav; Dopsaj, Violeta; Jelic-Ivanovic, Zorana
2013-01-01
Objectives. The study was designed to evaluate associations between symmetric dimethylarginine (SDMA), inflammation, and superoxide anion (O2∙−) with endothelial function and to determine their potential for screening of endothelial dysfunction in patients with chronic kidney disease (CKD) and renal transplant (RT) recipients. Materials and Methods. We included 64 CKD and 52 RT patients. Patients were stratified according to brachial artery flow-mediated dilation (FMD). Results. Logistic regression analysis showed that high SDMA and high sensitive C-reactive protein (hs-CRP) were associated with impaired FMD in CKD and RT patients, after adjustment for glomerular filtration rate. The ability of inflammation, SDMA, and O2∙− to detect impaired FMD was investigated by receiving operative characteristic analysis. Hs-CRP (area under the curves (AUC) = 0.754, P < 0.001), IL-6 (AUC = 0.699, P = 0.002), and SDMA (AUC = 0.689, P = 0.007) had the highest ability to detect impaired FMD. SDMA in combination with inflammatory parameters and/or O2∙− had better screening performance than SDMA alone. Conclusions. Our results indicate a strong predictable association between hs-CRP, SDMA, and endothelial dysfunction in CKD patients and RT recipients. The individual marker that showed the strongest discriminative ability for endothelial dysfunction is hs-CRP, but its usefulness as a discriminatory marker for efficient diagnosis of endothelial dysfunction should be examined in prospective studies. PMID:24167363
Memon, Lidija; Spasojevic-Kalimanovska, Vesna; Stanojevic, Natasa Bogavac; Kotur-Stevuljevic, Jelena; Simic-Ogrizovic, Sanja; Giga, Vojislav; Dopsaj, Violeta; Jelic-Ivanovic, Zorana; Spasic, Slavica
2013-11-01
The aim of the study was to determine the clinical usefulness of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and symmetric dimethylarginine (SDMA) for detection of renal and left ventricular (LV) diastolic dysfunction in chronic kidney disease (CKD) patients and renal transplant (RT) recipients. We included 98 CKD and 44 RT patients. We assessed LV function using pulsed-wave Doppler ultrasound. Diastolic dysfunction was defined when the E:A ratio was <1. Independent predictors of NT-proBNP levels were age, creatinine, and albumin in CKD patients and age and urea in RT patients. Determinants of SDMA in CKD patients were glomerular filtration rate (GFR) and NT-proBNP and creatinine in RT patients. In RT patients with diastolic dysfunction, NT-proBNP and SDMA were significantly higher than in patients without diastolic dysfunction (F = 7.478, P < 0.011; F = 2.631, P < 0.017). After adjustment for GFR, the differences were not seen. In CKD patients adjusted NT-proBNP and SDMA values for GFR were not significantly higher in patients with diastolic dysfunction than in patients without diastolic dysfunction. NT-proBNP is useful for detection of LV diastolic dysfunction in RT recipients. When evaluating both NT-proBNP and SDMA it is necessary to consider GFR as a confounding factor. © 2013 Wiley Periodicals, Inc.
Hall, Jean A.; MacLeay, Jennifer; Yerramilli, Maha; Obare, Edward; Yerramilli, Murthy; Schiefelbein, Heidi; Paetau-Robinson, Inke; Jewell, Dennis E.
2016-01-01
A prospective study was conducted in client-owned geriatric cats to evaluate the short- term effects of a test food on serum symmetric dimethylarginine (SDMA) and creatinine (Cr) concentrations. Test food contained functional lipids (fish oil), antioxidants (vitamins C and E), L-carnitine, botanicals (vegetables), highly bioavailable protein, and amino acid supplements. Cats (n = 80) were fed either test food or owner’s-choice foods (non-nutritionally controlled cohort). Cats were included based on age (≥ 9 years), indoor only, neutered, and free of chronic disease. At baseline, all cats had serum Cr concentrations within the reference interval. Renal function biomarkers and urinalysis results at baseline and after consuming test food or owner’s-choice foods for 3 and 6 months were evaluated. Cats consuming test food showed significant decreases in serum Cr and BUN concentrations across time. Overall, cats consuming owner’s-choice foods showed significant increases in serum SDMA concentrations at 3 and 6 months compared with baseline (P ≤ 0.05), whereas in cats consuming test food serum SDMA concentrations did not change. At baseline or during the 6-month feeding trial, 23 (28.8%) cats had increased serum SDMA, but normal serum Cr consistent with IRIS Stage 1 chronic kidney disease. This included 6 cats fed test food and 17 cats fed owner’s-choice foods. In the 6 cats fed test food, serum SDMA decreased in 3 cats and remained stable in 1 cat, whereas in the 17 cats fed owner’s-choice foods, serum SDMA increased in 13 cats and decreased or remained stable in 4 cats. The increase in serum SDMA concentration was significant (P = 0.02) only for cats fed owner’s-choice foods. These results suggest that nonazotemic cats with elevated serum SDMA (early renal insufficiency) when fed a food designed to promote healthy aging are more likely to demonstrate stable renal function compared with cats fed owner’s-choice foods. Cats fed owner’s-choice foods were more likely to demonstrate progressive renal insufficiency. PMID:27078852
Appel, Daniel; Seeberger, Miriam; Schwedhelm, Edzard; Czorlich, Patrick; Goetz, Alwin E; Böger, Rainer H; Hannemann, Juliane
2018-03-20
Delayed cerebral ischemia (DCI) is the major cause of lethality and neuronal damage in patients who survived the primary subarachnoid hemorrhage (SAH). Asymmetric and symmetric dimethylarginines (ADMA and SDMA) inhibit nitric oxide production from L-arginine via distinct mechanisms. Elevated ADMA levels are associated with vasospasm after SAH. We aimed to study the time course of ADMA and SDMA in plasma and ventricular cerebrospinal fluid (CSF) and their associations with DCI and outcome. We measured ADMA and SDMA in 34 SAH patients with an external ventricular drain at admission and on days 3, 6, 8, 12, and 15 and followed them up for clinical status and neurological outcome until 30 days post-discharge. DCI was defined as the appearance of new infarctions on cerebral computed tomography or magnetic resonance imaging. ADMA and SDMA plasma concentrations did not differ significantly at baseline between patients who suffered DCI (N = 14; 41%) and not; however, plasma ADMA reached a peak on days 8 and 15 after hemorrhage in patients with DCI (0.81-0.91 µmol/l). Baseline plasma L-arginine/ADMA ratio was significantly lower in patients with DCI (57.1 [34.3; 70.8] vs. 68.7 [55.7; 96.2]; p < 0.05). ADMA and SDMA concentrations in CSF were significantly higher in patients with DCI than without. In multivariable-adjusted linear regression models, CSF ADMA was negatively associated with the incidence of DCI (OR 0.03 [0.02-0.70]; p = 0.04), whereas CSF SDMA on the day of hemorrhage predicted poor neurological outcome until 30 days after discharge (OR 22.4 [1.21-416.02]; p = 0.04). Our study shows that ADMA and the L-arginine/ADMA ratio are associated with the incidence of DCI after SAH. By contrast, SDMA was associated with initial neuronal damage and poor neurological outcome after SAH. These data support the hypothesis that ADMA and L-arginine affect the pathophysiology of cerebral ischemia after SAH, while SDMA is a biomarker of neurological outcome after SAH.
Lamglait, Benjamin; Vandenbunder-Beltrame, Marielle
2017-09-01
Symmetric dimethylarginine (SDMA) has been shown to be a valuable biomarker for early detection of chronic kidney disease (CKD) in canine and feline patients. Recognition of early (subclinical) kidney disease would be of value in cheetahs (Acinonyx jubatus) as prevalence of CKD is relatively high in this species in captivity. Fifty-eight banked serum and plasma samples from seven adult cheetahs that died of CKD were analyzed for creatinine, urea, and SDMA. A marked increase in SDMA was noted on five of the tested cheetahs earlier than the rise of serum creatinine and urea (estimated 8-35 mo; mean 21.4 mo; median 22 mo). SDMA appears as an early biomarker to evaluate renal function for the diagnosis of CKD in cheetahs regardless of the cause of this disease.
Torrent, Esther; Planellas, Marta; Ordeix, Laura; Pastor, Josep; Rodon, Jaume; Solano-Gallego, Laia
2018-01-01
The aims of the study were to determine whether symmetric dimethylarginine (SDMA) was increased in dogs with leishmaniosis and to assess its relationship with creatinine concentration and urinary protein : creatinine ratio (UPC) to determine its utility as a marker of early excretory dysfunction. Fifty-three dogs with leishmaniosis classified according to the LeishVet clinical staging (stage I, n = 5, stage II, n = 30; stage III, n = 12; stage IV, n = 6) were selected and compared with 41 clinically healthy dogs. Thirty-nine dogs with leishmaniosis were also followed up for six months. SDMA concentrations on the day of diagnosis were significantly higher in dogs with leishmaniosis with respect to control dogs and in dogs from LeishVet stage IV when compared with the other stages. Increased UPC (>0.5), SDMA (>19 μ g/dL), and creatinine concentrations (≥1.4 mg/dL) were found in 47.1%, 15.1%, and 9.4% of dogs with leishmaniosis, respectively. SDMA concentration was increased in 24% of proteinuric dogs, in 7% of nonproteinuric dogs, and in four of five dogs with increased creatinine. SDMA concentration ≥ 25 μ g/dL was associated with clinical chronic kidney disease (CKD) after six months. Our results did not demonstrate advantages in using SDMA concentration as an early marker of CKD when compared to creatinine and UPC in canine leishmaniosis.
Torrent, Esther; Planellas, Marta; Ordeix, Laura; Pastor, Josep; Rodon, Jaume
2018-01-01
The aims of the study were to determine whether symmetric dimethylarginine (SDMA) was increased in dogs with leishmaniosis and to assess its relationship with creatinine concentration and urinary protein : creatinine ratio (UPC) to determine its utility as a marker of early excretory dysfunction. Fifty-three dogs with leishmaniosis classified according to the LeishVet clinical staging (stage I, n = 5, stage II, n = 30; stage III, n = 12; stage IV, n = 6) were selected and compared with 41 clinically healthy dogs. Thirty-nine dogs with leishmaniosis were also followed up for six months. SDMA concentrations on the day of diagnosis were significantly higher in dogs with leishmaniosis with respect to control dogs and in dogs from LeishVet stage IV when compared with the other stages. Increased UPC (>0.5), SDMA (>19 μg/dL), and creatinine concentrations (≥1.4 mg/dL) were found in 47.1%, 15.1%, and 9.4% of dogs with leishmaniosis, respectively. SDMA concentration was increased in 24% of proteinuric dogs, in 7% of nonproteinuric dogs, and in four of five dogs with increased creatinine. SDMA concentration ≥ 25 μg/dL was associated with clinical chronic kidney disease (CKD) after six months. Our results did not demonstrate advantages in using SDMA concentration as an early marker of CKD when compared to creatinine and UPC in canine leishmaniosis.
Reimann, Manja; Hamer, Mark; Malan, Nicolaas T; Schlaich, Markus P; Lambert, Gavin W; Ziemssen, Tjalf; Boeger, Rainer H; Malan, Leoné
2013-10-01
This study investigated the impact of stress on effectors of the L-arginine/nitric oxide (NO) system including the endogenous inhibitor asymmetric dimethylarginine (ADMA). Black (n = 168) and white (n = 206) South African teachers were exposed to a mental and a physical stressor for 1 minute, respectively. Serum samples for determination of l-arginine, NO metabolites, ADMA, and symmetric dimethylarginine (SDMA) were obtained at rest and during stress exposure. Perception of task stressfulness was assessed on a 7-point Likert scale, and psychological distress was estimated by the General Health Questionnaire. Black South Africans exhibited higher resting levels of NO metabolites (adjusted mean [standard error of the mean] = 11.3 [1.3] versus 3.9 [1.1] μmol/l, p < .001) but lower circulating ADMA (0.62 [0.02] versus 0.70 [0.02] μmol/l, p = .004) and SDMA (0.41 [0.01] versus 0.53 [0.01] μmol/l, p < .001) than did white South Africans. Ethnicity-by-psychological distress interaction was observed for resting levels of ADMA (p = .002), SDMA (p = .038), and L-arginine (p = .048). Ethnic differences in responses to experimental stress were evident for NO metabolites (blacks versus whites: 5.94 [1.55] versus -0.74 [1.25] μmol/l, p = .004) and SDMA (blacks versus whites: -0.02 [0.01] versus 0.02 [0.01] μmol/l, p = .004). Ethnicity-by-psychological distress interaction for stress responses was found for l-arginine/ADMA ratio (p = .027). The l-arginine/NO system is affected by psychosocial distress with higher susceptibility in black South Africans. This interaction may contribute to the higher cardiovascular disease risk in black South Africans.
Two distinct arginine methyltransferases are required for biogenesis of Sm-class ribonucleoproteins.
Gonsalvez, Graydon B; Tian, Liping; Ospina, Jason K; Boisvert, François-Michel; Lamond, Angus I; Matera, A Gregory
2007-08-27
Small nuclear ribonucleoproteins (snRNPs) are core components of the spliceosome. The U1, U2, U4, and U5 snRNPs each contain a common set of seven Sm proteins. Three of these Sm proteins are posttranslationally modified to contain symmetric dimethylarginine (sDMA) residues within their C-terminal tails. However, the precise function of this modification in the snRNP biogenesis pathway is unclear. Several lines of evidence suggest that the methyltransferase protein arginine methyltransferase 5 (PRMT5) is responsible for sDMA modification of Sm proteins. We found that in human cells, PRMT5 and a newly discovered type II methyltransferase, PRMT7, are each required for Sm protein sDMA modification. Furthermore, we show that the two enzymes function nonredundantly in Sm protein methylation. Lastly, we provide in vivo evidence demonstrating that Sm protein sDMA modification is required for snRNP biogenesis in human cells.
Two distinct arginine methyltransferases are required for biogenesis of Sm-class ribonucleoproteins
Gonsalvez, Graydon B.; Tian, Liping; Ospina, Jason K.; Boisvert, François-Michel; Lamond, Angus I.; Matera, A. Gregory
2007-01-01
Small nuclear ribonucleoproteins (snRNPs) are core components of the spliceosome. The U1, U2, U4, and U5 snRNPs each contain a common set of seven Sm proteins. Three of these Sm proteins are posttranslationally modified to contain symmetric dimethylarginine (sDMA) residues within their C-terminal tails. However, the precise function of this modification in the snRNP biogenesis pathway is unclear. Several lines of evidence suggest that the methyltransferase protein arginine methyltransferase 5 (PRMT5) is responsible for sDMA modification of Sm proteins. We found that in human cells, PRMT5 and a newly discovered type II methyltransferase, PRMT7, are each required for Sm protein sDMA modification. Furthermore, we show that the two enzymes function nonredundantly in Sm protein methylation. Lastly, we provide in vivo evidence demonstrating that Sm protein sDMA modification is required for snRNP biogenesis in human cells. PMID:17709427
Lüneburg, Nicole; Lieb, Wolfgang; Zeller, Tanja; Chen, Ming-Huei; Maas, Renke; Carter, Angela M.; Xanthakis, Vanessa; Glazer, Nicole L; Schwedhelm, Edzard; Seshadri, Sudha; Ikram, M. Arfan; Longstreth, W.T.; Fornage, Myriam; König, Inke R.; Loley, Christina; Ojeda, Francisco M.; Schillert, Arne; Wang, Thomas J.; Sticht, Heinrich; Kittel, Anja; König, Jörg; Benjamin, Emelia J.; Sullivan, Lisa M.; Bernges, Isabel; Anderssohn, Maike; Ziegler, Andreas; Gieger, Christian; Illig, Thomas; Meisinger, Christa; Wichmann, H.-Erich; Wild, Philipp S.; Schunkert, Heribert; Psaty, Bruce M.; Wiggins, Kerri L.; Heckbert, Susan R.; Smith, Nicholas; Lackner, Karl; Lunetta, Kathryn L.; Blankenberg, Stefan; Erdmann, Jeanette; Munzel, Thomas; Grant, Peter J.; Vasan, Ramachandran S.; Böger, Rainer H.
2016-01-01
Background Dimethylarginines (DMA) interfere with nitric oxide (NO) formation by inhibiting NO synthase (asymmetric dimethylarginine, ADMA) and L-arginine uptake into the cell (ADMA and symmetric dimethylarginine, SDMA). In prospective clinical studies ADMA has been characterized as a cardiovascular risk marker whereas SDMA is a novel marker for renal function and associated with all-cause mortality after ischemic stroke. The aim of the current study was to characterise the environmental and genetic contributions to inter-individual variability of these biomarkers. Methods and Results This study comprised a genome-wide association analysis of 3 well-characterized population-based cohorts (FHS (n=2992), GHS (n=4354) and MONICA/KORA F3 (n=581)) and identified replicated loci (DDAH1, MED23, Arg1 and AGXT2) associated with the inter-individual variability in ADMA, L-arginine and SDMA. Experimental in-silico and in-vitro studies confirmed functional significance of the identified AGXT2 variants. Clinical outcome analysis in 384 patients of the Leeds stroke study demonstrated an association between increased plasma levels of SDMA, AGXT2 variants and various cardiometabolic risk factors. AGXT2 variants were not associated with post-stroke survival in the Leeds study, nor were they associated with incident stroke in the CHARGE consortium. Conclusion These GWAS support the importance of DDAH1 and MED23/Arg1 in regulating ADMA and L-arginine metabolism, respectively, and identify a novel regulatory renal pathway for SDMA by AGXT2. AGXT2 variants might explain part of the pathogenic link between SDMA, renal function, and outcome. An association between AGXT2 variants and stroke is unclear and warrants further investigation. PMID:25245031
Hall, Jean A.; MacLeay, Jennifer; Yerramilli, Maha; Obare, Edward; Yerramilli, Murthy; Schiefelbein, Heidi; Paetau-Robinson, Inke; Jewell, Dennis E.
2016-01-01
A prospective study was conducted in client-owned geriatric dogs to evaluate the short-term effects of a test food on serum symmetric dimethylarginine (SDMA) and creatinine (Cr) concentrations. Test food contained functional lipids (fish oil), antioxidants (lipoic acid, vitamins C and E), L-carnitine, botanicals (fruits and vegetables), controlled sodium concentration, and high quality protein sources (high bioavailability and an ideal amino acid composition). Dogs (n = 210) were fed either test food or owner’s-choice foods (non-nutritionally controlled cohort). Dogs were included based on age and body weight: small (6.8 to 11.4 kg) and medium dogs (11.5 to 22.7 kg) were ≥ 9 years, whereas dogs >22.7 kg were ≥ 7 years at baseline. At baseline, all dogs had to have serum Cr concentrations within the reference interval and be free of chronic disease. Renal function biomarkers and urinalysis results at baseline, and after consuming test food or owner’s-choice foods for 3 and 6 months, were evaluated. Only dogs consuming test food showed significant decreases in serum SDMA and Cr concentrations (both P ≤ 0.05) across time. At baseline or during the 6-month feeding trial, 18 dogs (8.6%) had increased serum SDMA, but normal serum Cr, consistent with IRIS Stage 1 chronic kidney disease. This included 9 dogs fed test food and 9 dogs fed owner’s-choice foods. Compared with baseline, after feeding 9 dogs test food for 6 months, serum SDMA decreased in 8 dogs and increased in 1 dog. After feeding 9 dogs owner’s-choice foods for 6 months, serum SDMA decreased in 4 dogs and increased in 4 dogs (remained stable in 1 dog). The decreases in serum SDMA and Cr concentrations were significant (both P = 0.03) only for dogs fed test food. These results suggest that nonazotemic dogs with elevated serum SDMA (early renal insufficiency) when fed a test food designed to promote healthy aging are more likely to demonstrate improved renal function compared with dogs fed owner’s-choice foods. PMID:27088214
Nitric oxide synthase inhibitors and hypertension in children and adolescents.
Goonasekera, C D; Rees, D D; Woolard, P; Frend, A; Shah, V; Dillon, M J
1997-08-01
To establish the role played by the circulating nitric oxide synthase inhibitors N(G)-monomethyl-L-arginine (L-NMMA), asymmetrical dimethyl arginine (ADMA) and symmetric dimethyl arginine (SDMA) and its association with hypertension of children and adolescents. We measured plasma concentrations of L-NMMA, ADMA and SDMA in 38 hypertensives (median age 7.7 years) and in nine healthy normotensive controls (median age 8.2 years) using high-performance liquid chromatography. In addition, their plasma renin activity was determined. The subjects' glomerular filtration rates were calculated from plasma creatinine and height measurements. To determine the vasoactive potency of the arginine analogues, concentration-response curves were plotted for the responses in isolated endothelium-intact and endothelium-denuded mouse aortic rings that had been pre-contracted by administration of a threshold concentration of phenylephrine. Plasma ADMA and SDMA concentrations in members of the hypertensive group [0.23 +/- 0.03 and 1.37 +/- 0.06 micromol/l, respectively (means +/- SEM)] were significantly higher than those in members of the control group (ADMA 0.10 +/- 0.01 micromol/l and SDMA 1.18 +/- 0.06 micromol/l). Plasma concentrations of L-NMMA were similar in members of the hypertensive (0.21 +/- 0.01 micromol/l) and control (0.18 +/- 0.02 micromol/l) groups. The glomerular filtration rate of the hypertensive group was below normal [70.4 +/- 5.4 ml/min per 1.73 m2 (mean +/- SEM)] and was significantly associated with elevated plasma concentrations of ADMA (r = -0.77, P < 0.001), SDMA (r = -0.38, P = 0.02) and L-NMMA (r = 0.35, P = 0.03). Higher plasma ADMA concentrations were associated with a lower plasma renin activity (r = -0.36, P = 0.04). The vasoactive potencies of ADMA (concentration for half-maximal effect with the endothelium intact 25.4 +/- 7.1 micromol/l) and L-NMMA (concentration for half-maximal effect with the endothelium intact 8.2 +/- 2.9 micromol/l) was significantly (P < 0.05) greater than that of SDMA. Both ADMA and L-NMMA (at 3 micromol/l concentrations) initiated a significant vasocontractile response from baseline (P = 0.03 and P < 0.001, respectively). These effects were absent after the endothelium had been removed. SDMA had no effect. Plasma ADMA and SDMA levels are increased in hypertensive children. By inference from in-vitro data, ADMA appears to attain sufficient concentrations to produce a significant change in vascular tone and hence might play a role in the pathophysiology of childhood hypertension.
Boelaert, Jente; Schepers, Eva; Glorieux, Griet; Eloot, Sunny; Vanholder, Raymond; Lynen, Frédéric
2016-05-13
Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis, and its structural isomer symmetric dimethylarginine (SDMA) are uremic toxins accumulating in chronic kidney disease (CKD) patients. The objective of this study was to develop and validate a robust UPLC-MS/MS method for the simultaneous determination of ADMA and SDMA in human serum. Chromatographic separation after butyl ester derivatization was achieved on an Acquity UPLC BEH C18 column, followed by tandem mass spectrometric detection. After validation, the applicability of the method was evaluated by the analysis of serum samples from 10 healthy controls and 77 CKD patients on hemodialysis (CKD5HD). Both ADMA (0.84 ± 0.19 µM vs. 0.52 ± 0.07 µM) and SDMA concentrations (2.06 ± 0.82 µM vs. 0.59 ± 0.13 µM) were significantly (p < 0.001) elevated in CKD5HD patients compared to healthy controls. In general, low degrees of protein binding were found for both ADMA and SDMA. In addition, an established commercially available ELISA kit was utilized on the same samples (n = 87) to compare values obtained both with ELISA and UPLC-MS/MS. Regression analysis between these two methods was significant (p < 0.0001) but moderate for both ADMA (R = 0.78) and SDMA (R = 0.72).
Nitric Oxide-Related Biological Pathways in Patients with Major Depression
Baranyi, Andreas; Amouzadeh-Ghadikolai, Omid; Rothenhäusler, Hans-Bernd; Theokas, Simon; Robier, Christoph; Baranyi, Maria; Koppitz, Michael; Reicht, Gerhard; Hlade, Peter; Meinitzer, Andreas
2015-01-01
Background Major depression is a well-known risk factor for cardiovascular diseases and increased mortality following myocardial infarction. However, biomarkers of depression and increased cardiovascular risk are still missing. The aim of this prospective study was to evaluate, whether nitric-oxide (NO) related factors for endothelial dysfunction, such as global arginine bioavailability, arginase activity, L-arginine/ADMA ratio and the arginine metabolites asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) might be biomarkers for depression-induced cardiovascular risk. Methods In 71 in-patients with major depression and 48 healthy controls the Global Arginine Bioavailability Ratio (GABR), arginase activity (arginine/ornithine ratio), the L-arginine/ADMA ratio, ADMA, and SDMA were determined by high-pressure liquid chromatography. Psychiatric and laboratory assessments were obtained at baseline at the time of in-patient admittance and at the time of hospital discharge. Results The ADMA concentrations in patients with major depression were significantly elevated and the SDMA concentrations were significantly decreased in comparison with the healthy controls. Even after a first improvement of depression, ADMA and SDMA levels remained nearly unchanged. In addition, after a first improvement of depression at the time of hospital discharge, a significant decrease in arginase activity, an increased L-arginine/ADMA ratio and a trend for increased global arginine bioavailability were observed. Conclusions Our study results are evidence that in patients with major depression ADMA and SDMA might be biomarkers to indicate an increased cardiovascular threat due to depression-triggered NO reduction. GABR, the L-arginine/ADMA ratio and arginase activity might be indicators of therapy success and increased NO production after remission. PMID:26581044
Reyhani, Aylin; Celik, Yahya; Karadag, Hakan; Gunduz, Ozgur; Asil, Talip; Sut, Necdet
2017-07-01
Experimental and clinical data strongly suggests that nitric oxide (NO) plays a pivotal role in migraine. This is also supported by studies of migraine induced by substances that release NO. NO is synthesized from L-arginine by endothelial NO synthase (NOS). Asymmetric dimethylarginine (ADMA) is the major endogenous competitive inhibitor of NOS. Symmetric dimethylarginine (SDMA) is an inactive stereoisomer of ADMA. It may reduce NO production by competing with arginine for cellular uptake. The aim of this study was to measure the levels of ADMA, SDMA and L-arginine in migraine patients during the interictal period. One hundred migraine patients and 100 healthy volunteers were recruited. The patients were in the interictal period and classified into two groups as having migraine with aura and migraine without aura. Their serum ADMA, SDMA and L-arginine levels were measured by high-performance liquid chromotography (HPLC) method. ADMA, SDMA and L-arginine levels were significantly higher in migraine patients compared to the control group. But there was no difference between the patients with and without aura. These results suggest that NOS inhibitors and L-arginine/NO pathway plays an important role in migraine pathopysiology.
Potočnjak, Ines; Radulović, Bojana; Degoricija, Vesna; Trbušić, Matias; Pregartner, Gudrun; Berghold, Andrea; Meinitzer, Andreas; Frank, Saša
2018-06-15
Serum concentrations of asymmetric (ADMA) and symmetric (SDMA) dimethylarginine are established predictors of total and cardiovascular mortality. However, the predictive capacity of ADMA and SDMA for hospital and 3-months mortality of patients with acute heart failure (AHF) is unknown. Out of 152 included AHF patients, 79 (52%) were female, and the mean patient age was 75.2 ± 10.3 years. Hospital and three-month mortality rates were 14.5% and 27.4%, respectively. Serum ADMA and SDMA levels at admission, determined by reversed phase high performance liquid chromatography, were higher in patients having at least one of the three signs implying venous volume overload (enlarged liver, ascites, peripheral edema), a consequence of right-sided heart failure, compared to patients without those signs. Univariable logistic regression analyses revealed a significant positive association of ADMA and SDMA concentrations with hospital mortality [odds ratio (OR) and 95% confidence interval (CI) per standard deviation (SD) increase: 2.22 (1.37-3.79), p = 0.002, and 2.04 (1.34-3.18), p = 0.001, respectively], and 3-months mortality [2.06 (1.36-3.26), p = 0.001, and 2.52 (1.67-4.04), p < 0.001, respectively]. These associations remained significant after adjusting for age, sex, mean arterial pressure, low-density lipoprotein cholesterol, glomerular filtration rate, and N-terminal pro-brain natriuretic peptide. We conclude that ADMA and SDMA concentrations are associated with hospital and 3-month mortality and are increased by venous volume overload in AHF patients. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Optimizing Satellite Communications With Adaptive and Phased Array Antennas
NASA Technical Reports Server (NTRS)
Ingram, Mary Ann; Romanofsky, Robert; Lee, Richard Q.; Miranda, Felix; Popovic, Zoya; Langley, John; Barott, William C.; Ahmed, M. Usman; Mandl, Dan
2004-01-01
A new adaptive antenna array architecture for low-earth-orbiting satellite ground stations is being investigated. These ground stations are intended to have no moving parts and could potentially be operated in populated areas, where terrestrial interference is likely. The architecture includes multiple, moderately directive phased arrays. The phased arrays, each steered in the approximate direction of the satellite, are adaptively combined to enhance the Signal-to-Noise and Interference-Ratio (SNIR) of the desired satellite. The size of each phased array is to be traded-off with the number of phased arrays, to optimize cost, while meeting a bit-error-rate threshold. Also, two phased array architectures are being prototyped: a spacefed lens array and a reflect-array. If two co-channel satellites are in the field of view of the phased arrays, then multi-user detection techniques may enable simultaneous demodulation of the satellite signals, also known as Space Division Multiple Access (SDMA). We report on Phase I of the project, in which fixed directional elements are adaptively combined in a prototype to demodulate the S-band downlink of the EO-1 satellite, which is part of the New Millennium Program at NASA.
Tsikas, Dimitrios; Bollenbach, Alexander; Savvidou, Makrina D
2018-02-01
L-Arginine (Arg) is the enzymatic precursor of nitric oxide (NO) which has multiple biological functions. Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) are endogenous inhibitors of NO. We hypothesized that the ADMA and SDMA have additional biological functions in pregnancy, beyond NO synthesis, and may play a role in the regulation of birthweight (BW). To investigate this issue, we measured the plasma concentration of ADMA, SDMA, Arg and the NO metabolites nitrite and nitrate, at 23-25 weeks of gestation in women with normal placental function (Group 1) and in women with impaired placental perfusion; 19 of these women had normal outcome (Group 2), 14 had a fetus that was growth restricted (Group 3), and 10 women eventually developed preeclampsia (Group 4). BW percentile was found to inversely correlate with maternal plasma ADMA concentration in Group 3 (r = - 0.872, P < 0.001) and in Group 4 (r = - 0.800, P < 0.05). But, BW percentile did not correlate with the maternal plasma concentration of Arg, SDMA, nitrate or nitrite. Our results suggest that maternal plasma ADMA concentration is an important indicator of fetal growth restriction in women with impaired placental perfusion independent of NO.
Hall, J A; Yerramilli, M; Obare, E; Yerramilli, M; Yu, S; Jewell, D E
2014-12-01
The purpose of this study was to determine whether feeding cats reduced protein and phosphorus foods with added fish oil, L-carnitine, and medium-chain triglycerides (MCT) altered serum biomarkers of renal function. Thirty-two healthy cats, mean age 14.0 (8.3-19.6) years, were fed control food or one of two experimental foods for 6 months. All foods had similar concentrations of moisture, protein, and fat (approximately 8.0%, 26.5%, and 20.0%, respectively). Both experimental foods contained added fish oil (1.5%) and L-carnitine (500 mg/kg). Experimental-food 2 also contained increased MCT (10.5% from coconut oil), 1.5% added corn oil, and reduced animal fat. Glomerular filtration rate (GFR), serum biochemistries, renal function biomarkers including serum creatinine (sCr) and symmetrical dimethylarginine (SDMA), and plasma metabolomic profiles were measured at baseline, and at 1.5, 3, and 6 months. Body composition was determined by dual-energy X-ray absorptiometry. Although both experimental foods altered plasma fatty acids, carnitine and related metabolites, and lysophospholipid concentrations, there were no changes in renal function biomarkers. There was, however, a benefit in using SDMA versus sCr to assess renal function in older cats with less total lean mass. Compared with cats <12 years, those >15 years had lower total lean mass (P < 0.01), lower GFR (P = 0.04), and lower sCr concentrations (P < 0.01). However, SDMA concentrations (P < 0.01) were higher in older cats. This study shows that in cats, serum SDMA concentration is more highly correlated with GFR than sCr concentration, and, unlike sCr, which declines with age because of muscle wasting, SDMA increases as GFR declines with age. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ayoubian, Hiresh; Fröhlich, Thomas; Pogodski, Dagmar; Flatley, Andrew; Kremmer, Elisabeth; Schepers, Aloys; Feederle, Regina; Arnold, Georg J; Grässer, Friedrich A
2017-08-01
The Epstein-Barr virus is a human herpes virus with oncogenic potential. The virus-encoded nuclear antigen 2 (EBNA2) is a key mediator of viral tumorigenesis. EBNA2 features an arginine-glycine (RG) repeat at amino acids (aa)339-354 that is essential for the transformation of lymphocytes and contains symmetrically (SDMA) and asymmetrically (ADMA) di-methylated arginine residues. The SDMA-modified EBNA2 binds the survival motor neuron protein (SMN), thus mimicking SMD3, a cellular SDMA-containing protein that interacts with SMN. Accordingly, a monoclonal antibody (mAb) specific for the SDMA-modified RG repeat of EBNA2 also binds to SMD3. With the novel mAb 19D4 we now show that EBNA2 contains mono-methylated arginine (MMA) residues within the RG repeat. Using 19D4, we immune-precipitated and analysed by mass spectrometry cellular proteins in EBV-transformed B-cells that feature MMA motifs that are similar to the one in EBNA2. Among the cellular proteins identified, we confirmed by immunoprecipitation and/or Western blot analyses Aly/REF, Coilin, DDX5, FXR1, HNRNPK, LSM4, MRE11, NRIP, nucleolin, PRPF8, RBM26, SMD1 (SNRDP1) and THRAP3 proteins that are either known to contain MMA residues or feature RG repeat sequences that probably serve as methylation substrates. The identified proteins are involved in splicing, tumorigenesis, transcriptional activation, DNA stability and RNA processing or export. Furthermore, we found that several proteins involved in energy metabolism are associated with MMA-modified proteins. Interestingly, the viral EBNA1 protein that features methylated RG repeat motifs also reacted with the antibodies. Our results indicate that the region between aa 34-52 of EBNA1 contains ADMA or SDMA residues, while the region between aa 328-377 mainly contains MMA residues.
Grooteman, Muriel P C; Wauters, Inge M P M J; Teerlink, Tom; Twisk, Jos W R; Nubé, Menso J
2007-01-01
Asymmetric dimethylarginine (ADMA) levels are increased in hemodialysis (HD) patients. Reports on the effect of various dialysis strategies on ADMA, symmetric dimethylarginine (SDMA) and L-arginine levels are inconclusive. In this randomized crossover study, 15 patients were dialyzed for 4 weeks with 4 dialyzers, differing in biocompatibility and flux. Dimethylarginine and L-arginine levels were assessed at baseline, and after 4 weeks both before and after HD. During HD, ADMA and SDMA levels decreased significantly with all dialyzers. Dimethylarginine and L-arginine levels remained stable after 4 weeks of HD with each membrane. After pooling all data, values were mainly explained by variation between time points and patients, not by the type of dialyzer. Despite an intradialytic decrease in dimethylarginines, no changes occurred after 4 weeks of HD with either membrane. Furthermore, the variability of AMDA, SDMA and L-arginine levels was far more dependent on patient-related factors than on the type of dialyzer applied. Copyright 2007 S. Karger AG, Basel.
PRMT7, a new protein arginine methyltransferase that synthesizes symmetric dimethylarginine.
Lee, Jin-Hyung; Cook, Jeffry R; Yang, Zhi-Hong; Mirochnitchenko, Olga; Gunderson, Samuel I; Felix, Arthur M; Herth, Nicole; Hoffmann, Ralf; Pestka, Sidney
2005-02-04
The cDNA for PRMT7, a recently discovered human protein-arginine methyltransferase (PRMT), was cloned and expressed in Escherichia coli and mammalian cells. Immunopurified PRMT7 actively methylated histones, myelin basic protein, a fragment of human fibrillarin (GAR) and spliceosomal protein SmB. Amino acid analysis showed that the modifications produced were predominantly monomethylarginine and symmetric dimethylarginine (SDMA). Examination of PRMT7 expressed in E. coli demonstrated that peptides corresponding to sequences contained in histone H4, myelin basic protein, and SmD3 were methylated. Furthermore, analysis of the methylated proteins showed that symmetric dimethylarginine and relatively small amounts of monomethylarginine and asymmetric dimethylarginine were produced. SDMA was also formed when a GRG tripeptide was methylated by PRMT7, indicating that a GRG motif is by itself sufficient for symmetric dimethylation to occur. Symmetric dimethylation is reduced dramatically compared with monomethylation as the concentration of the substrate is increased. The data demonstrate that PRMT7 (like PRMT5) is a Type II methyltransferase capable of producing SDMA modifications in proteins.
Serum L-arginine and dimethylarginine levels in migraine patients with brain white matter lesions.
Erdélyi-Bótor, Szilvia; Komáromy, Hedvig; Kamson, David Olayinka; Kovács, Norbert; Perlaki, Gábor; Orsi, Gergely; Molnár, Tihamér; Illes, Zsolt; Nagy, Lajos; Kéki, Sándor; Deli, Gabriella; Bosnyák, Edit; Trauninger, Anita; Pfund, Zoltán
2017-05-01
Background/Aim Migraine is a risk factor for the formation of silent brain white matter lesions (WMLs) that are possibly ischemic in nature. Although dysfunction of the L-arginine/nitric oxide (NO) pathway has been associated with oxidative stress and endothelial dysfunction in migraine, its role in WML development has not been specifically investigated. Thus, this prospective study aimed to measure the serum concentrations of the NO substrate L-arginine, the NO synthase inhibitor asymmetric dimethylarginine (ADMA), and the L-arginine transport regulator symmetric dimethylarginine (SDMA) in migraine patients in a headache-free period. Methods All participants underwent MR imaging to assess for the presence of WMLs on fluid-attenuated inversion recovery imaging. Altogether 109 migraine patients (43 with lesions, 66 without lesions) and 46 control individuals were studied. High-performance liquid chromatography was used to quantify L-arginine, ADMA and SDMA serum concentrations. Migraine characteristics were investigated, and participants were screened for risk factors that can lead to elevated serum ADMA levels independent of migraine. Results Migraine patients and controls did not differ in regard to vascular risk factors. Migraineurs with WMLs had a longer disease duration ( p < 0.001) and a higher number of lifetime headache attacks ( p = 0.005) than lesion-free patients. Higher L-arginine serum levels were found in both migraine subgroups compared to controls ( p < 0.001). Migraine patients with WMLs showed higher ADMA concentrations than lesion-free patients and controls ( p < 0.001, for both). In migraineurs, the presence of WMLs, aura and increasing age proved to be significant predictors of increased ADMA levels ( p = 0.008, 0.047 and 0.012, respectively). SDMA serum levels of lesional migraineurs were higher than in nonlesional patients ( p < 0.001). The presence of lesions and increasing age indicated an increased SDMA level ( p = 0.017 and 0.001, respectively). Binary logistic regression analysis showed that ADMA level ( p = 0.006), increasing age ( p = 0.017) and the total number of lifetime migraine attacks ( p = 0.026) were associated with an increased likelihood of exhibiting WMLs. There was no significant effect of age on ADMA and SDMA concentrations in controls. Conclusions Elevated ADMA levels may impact the pathogenesis of migraine-related WMLs by influencing cerebrovascular autoregulation and vasomotor reactivity. Higher SDMA concentrations may indirectly influence NO synthesis by reducing substrate availability. Elevated L-arginine serum levels might reflect an increased demand for NO synthesis.
HPLC-MS/MS investigation of biochemical markers for the disclosure of erythropoietin abuse in sports
NASA Astrophysics Data System (ADS)
Appolonova, S. A.; Dikunets, M. A.; Rodchenkov, G. M.
2009-04-01
The polypeptide hormone erythropoietin (EPO), which is a forbidden doping drug, was determined by high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS). The hypothesis about the influence of EPO on the asymmetric dimethylarginine (ADMA)-dimethylargininedime-thylaminohydrolase (DDAH)-NO-synthase system was verified. Changes in this system can serve as indirect biochemical markers of the presence of the forbidden EPO drug in the organism. In the test group, the concentrations of biochemical markers varied from 10 to 40 μg/ml for ADMA and symmetrical DMA (SDMA) and from 0.5 to 10 μg/ml for arginine and citrulline. A single intravenous administration of r-HuEPO (Epocrin, 2000 ME/day) for two volunteers reliably increased ADMA, SDMA, arginine, and citrulline concentrations to 40-270 μg/ml, 40-240μg/ml, 10-60 μg/ml, and 12-140 μg/ml, respectively, with respect to the reference values. The simultaneous increase in arginine, methylarginines, and citrulline contents could be an indirect marker of EPO abuse. The method is recommended for fast screening analysis.
Schlesinger, Sabrina; Sonntag, Svenja R.
2016-01-01
Background A growing number of studies linked elevated concentrations of circulating asymmetric (ADMA) and symmetric (SDMA) dimethylarginine to mortality and cardiovascular disease (CVD) events. To summarize the evidence, we conducted a systematic review and quantified associations of ADMA and SDMA with the risks of all-cause mortality and incident CVD in meta-analyses accounting for different populations and methodological approaches of the studies. Methods Relevant studies were identified in PubMed until February 2015. We used random effect models to obtain summary relative risks (RR) and 95% confidence intervals (95%CIs), comparing top versus bottom tertiles. Dose-response relations were assessed by restricted cubic spline regression models and potential non-linearity was evaluated using a likelihood ratio test. Heterogeneity between subgroups was assessed by meta-regression analysis. Results For ADMA, 34 studies (total n = 32,428) investigating associations with all-cause mortality (events = 5,035) and 30 studies (total n = 30,624) investigating the association with incident CVD (events = 3,396) were included. The summary RRs (95%CI) for all-cause mortality were 1.52 (1.37–1.68) and for CVD 1.33 (1.22–1.45), comparing high versus low ADMA concentrations. Slight differences were observed across study populations and methodological approaches, with the strongest association of ADMA being reported with all-cause mortality in critically ill patients. For SDMA, 17 studies (total n = 18,163) were included for all-cause mortality (events = 2,903), and 13 studies (total n = 16,807) for CVD (events = 1,534). High vs. low levels of SDMA, were associated with increased risk of all-cause mortality [summary RR (95%CI): 1.31 (1.18–1.46)] and CVD [summary RR (95%CI): 1.36 (1.10–1.68) Strongest associations were observed in general population samples. Conclusions The dimethylarginines ADMA and SDMA are independent risk markers for all-cause mortality and CVD across different populations and methodological approaches. PMID:27812151
Ivanova, Mariela; Artusi, Carlo; Boffa, Giovanni Maria; Zaninotto, Martina; Plebani, Mario
2010-11-11
Asymmetric dimethylarginine (ADMA) has been suggested as a possible marker of endothelial dysfunction, and interest in its use in clinical practice is increasing. However, the potential role of symmetric dimethylarginine (SDMA) as an endogenous marker of renal function, has been less widely investigated. The aims of the present study were therefore to determine reference values for dimethylarginines in plasma after method validation, and to ascertain ADMA plasma concentrations in patients with disorders characterized by endothelial dysfunction; a further end-point was to investigate the relationship between SDMA plasma concentrations and estimated GFR (eGFR) as well as plasmatic creatinine in patients with chronic kidney disease (CKD). HPLC with fluorescence detection was used for the determination of plasma dimethylarginines. To verify the clinical usefulness of ADMA and SDMA, values from 4 groups of patients at a high risk of cardiovascular complications as well renal dysfunction (chronic heart failure n=126; type II diabetes n=43; pulmonary arterial hypertension n=17; chronic kidney disease n=42) were evaluated, and compared with the reference values, obtained from 225 blood donors. The intra- and inter-assay CVs (<5.2%), the absolute and relative recoveries (96-106%) were highly satisfactory. ADMA levels were significantly elevated in all groups of patients compared with controls (p<0.001) with the exception of samples from patients with type II diabetes. SDMA levels were significantly elevated both in the patients with chronic kidney disease and in the patients with type II diabetes complicated by renal insufficiency, the values being closely correlated with both eGFR (R=0.740) and plasmatic creatinine (R=0.700). The findings made in the present study shows that ADMA levels are significantly increased in patients with diseases associated with endothelial dysfunction This molecule might, therefore, be used as a biochemical marker for the evaluation of endothelial function. Furthermore, the preliminary results reported suggest that SDMA might be a reliable marker of renal function, especially in peadiatric populations, for which the use of eGFR is not recommended. 2010 Elsevier B.V. All rights reserved.
Plasma proANP and SDMA and microRNAs are associated with chronic mitral regurgitation in a pig model
Cirera, Susanna; Moesgaard, Sophia G; Zois, Nora E; Ravn, Nathja; Goetze, Jens P; Cremer, Signe E; Teerlink, Tom; Leifsson, Páll S; Honge, Jesper L; Hasenkam, J Michael; Olsen, Lisbeth H
2013-01-01
Objective Non-ischemic mitral regurgitation (MR) is primarily caused by myxomatous mitral valve (MV) disease leading to adaptive remodeling, enlargement, and dysfunction of the left ventricle. The aim of this study was to examine the regulation of plasma markers and several cardiac key genes in a novel porcine model of non-ischemic MR. Methods and results Twenty-eight production pigs (Sus scrofa) were randomized to experimental MR or sham surgery controls. MR was induced by external suture(s) through the posterior MV leaflet and quantified using echocardiography. The experimental group was subdivided into mild MR (mMR, MR=20–50%, n=10) and moderate/severe MR (sMR, MR >50%, n=6) and compared with controls (CON, MR ≤10%, n=12). Eight weeks postoperatively, follow-up examinations were performed followed by killing. Circulating concentrations of pro-atrial natriuretic peptide (proANP), l-arginine, asymmetric dimethylarginine, and symmetric dimethylarginine (SDMA) were measured. MV, anterior papillary muscle, and left ventricular free wall tissues were collected to quantify mRNA expression of eNOS (NOS3), iNOS (NOS2), MMP9, MMP14, ANP (NPPA), BNP (NPPB), and TGFB1, 2, and 3 and five microRNAs by quantitative real-time PCR. Pigs with sMR displayed markedly increased plasma proANP and SDMA concentrations compared with both controls and mMR (P<0.05). The expression of all genes examined differed significantly between the three localizations in the heart. miR-21 and miR-133a were differently expressed among the experimental groups (P<0.05). Conclusions Plasma proANP and SDMA levels and tissue expression of miR-21 and miR-133a are associated with severity of chronic MR in an experimental porcine model. PMID:24029364
Wiśniewski, Jerzy; Fleszar, Mariusz G; Piechowicz, Joanna; Krzystek-Korpacka, Małgorzata; Chachaj, Angelika; Szuba, Andrzej; Lorenc-Kukula, Katarzyna; Masłowski, Leszek; Witkiewicz, Wojciech; Gamian, Andrzej
2017-11-01
Nitric oxide (NO) is a regulatory molecule involved in many biological processes. NO is produced by nitric oxide synthase by conversion of l-arginine to l-citrulline. l-Arginine methylated derivatives, asymmetric and symmetric dimethylarginines (asymmetric dimethylarginine, ADMA, and symmetric dimethylarginine, SDMA), regulate l-arginine availability and the activity of nitric oxide synthase. As such, they have been frequently investigated as potential biomarkers in pathologies associated with dysfunctions in NO synthesis. Here, we present a new multistep analytical methodology based on liquid chromatography combined with mass spectrometry for the accurate identification of l-arginine, l-citrulline, ADMA and SDMA. Compounds are measured as stable 2,3,4,5,6-pentafluorobenzoyl chloride derivatives, which allows for simultaneous analysis of all compounds through chromatographic separation of ADMA and SDMA using a reverse-phase column. Serum aliquots (100 μL) were spiked with isotope-labeled internal standards and sodium carbonate buffer. The derivatization process was carried out at 25°C for 10 minu using pentafluorobenzoyl chloride as derivatization reagent. Calibration demonstrated good linearity (R 2 = 0.9966-0.9986) for all derivatized compounds. Good accuracy (94.67-99.91%) and precision (1.92-11.8%) were observed for the quality control samples. The applicability of the method was evaluated in a cohort of angiological patients and healthy volunteers. The method discerned significantly lower l-arginine and l-citrulline in angiologic patients. This robust and fast LC-ESI-MS method may be a useful tool in quantitative analysis of l-arginine, ADMA, SDMA and l-citrulline. Copyright © 2017 John Wiley & Sons, Ltd.
Linz, Thomas H.; Snyder, Christa M.; Lunte, Susan M.
2013-01-01
The methylated arginines (MAs) monomethylarginine (MMA), asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) have been shown to be independent predictors of cardiovascular disease. This article describes progress regarding the development of an analytical method capable of rapidly analyzing MAs using capillary electrophoresis (CE) and microchip electrophoresis (MCE) with laser-induced fluorescence (LIF) detection. Several parameters including buffer composition and separation voltage were optimized to achieve an ideal separation. The analytes of interest were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) to produce fluorescent 1-cyanobenz[f]isoindole (CBI) derivatives and then subjected to CE analysis. Baseline resolution of SDMA, ADMA, MMA, and arginine was achieved in less than 8 min. The limits of detection for SDMA, ADMA, MMA, and arginine were determined to be 15, 20, 25, and 5 nM, respectively, which are well below the expected plasma concentrations. The CE separation method was then transferred to a glass MCE device with LIF detection. MAs were baseline resolved in 3 min on-chip using a 14 cm separation channel with detection limits of approximately 10 nM for each species. To the best of the authors’ knowledge, this is the first report of the separation of MAs by MCE. PMID:22357605
Multi-Touch Tabletop System Using Infrared Image Recognition for User Position Identification.
Suto, Shota; Watanabe, Toshiya; Shibusawa, Susumu; Kamada, Masaru
2018-05-14
A tabletop system can facilitate multi-user collaboration in a variety of settings, including small meetings, group work, and education and training exercises. The ability to identify the users touching the table and their positions can promote collaborative work among participants, so methods have been studied that involve attaching sensors to the table, chairs, or to the users themselves. An effective method of recognizing user actions without placing a burden on the user would be some type of visual process, so the development of a method that processes multi-touch gestures by visual means is desired. This paper describes the development of a multi-touch tabletop system using infrared image recognition for user position identification and presents the results of touch-gesture recognition experiments and a system-usability evaluation. Using an inexpensive FTIR touch panel and infrared light, this system picks up the touch areas and the shadow area of the user's hand by an infrared camera to establish an association between the hand and table touch points and estimate the position of the user touching the table. The multi-touch gestures prepared for this system include an operation to change the direction of an object to face the user and a copy operation in which two users generate duplicates of an object. The system-usability evaluation revealed that prior learning was easy and that system operations could be easily performed.
Multi-Touch Tabletop System Using Infrared Image Recognition for User Position Identification
Suto, Shota; Watanabe, Toshiya; Shibusawa, Susumu; Kamada, Masaru
2018-01-01
A tabletop system can facilitate multi-user collaboration in a variety of settings, including small meetings, group work, and education and training exercises. The ability to identify the users touching the table and their positions can promote collaborative work among participants, so methods have been studied that involve attaching sensors to the table, chairs, or to the users themselves. An effective method of recognizing user actions without placing a burden on the user would be some type of visual process, so the development of a method that processes multi-touch gestures by visual means is desired. This paper describes the development of a multi-touch tabletop system using infrared image recognition for user position identification and presents the results of touch-gesture recognition experiments and a system-usability evaluation. Using an inexpensive FTIR touch panel and infrared light, this system picks up the touch areas and the shadow area of the user’s hand by an infrared camera to establish an association between the hand and table touch points and estimate the position of the user touching the table. The multi-touch gestures prepared for this system include an operation to change the direction of an object to face the user and a copy operation in which two users generate duplicates of an object. The system-usability evaluation revealed that prior learning was easy and that system operations could be easily performed. PMID:29758006
Web-based multi-channel analyzer
Gritzo, Russ E.
2003-12-23
The present invention provides an improved multi-channel analyzer designed to conveniently gather, process, and distribute spectrographic pulse data. The multi-channel analyzer may operate on a computer system having memory, a processor, and the capability to connect to a network and to receive digitized spectrographic pulses. The multi-channel analyzer may have a software module integrated with a general-purpose operating system that may receive digitized spectrographic pulses for at least 10,000 pulses per second. The multi-channel analyzer may further have a user-level software module that may receive user-specified controls dictating the operation of the multi-channel analyzer, making the multi-channel analyzer customizable by the end-user. The user-level software may further categorize and conveniently distribute spectrographic pulse data employing non-proprietary, standard communication protocols and formats.
Bjørke-Jenssen, Astrid; Ueland, Per Magne; Bjørke-Monsen, Anne-Lise
2017-12-14
Arginine is a constituent of proteins and a precursor for polyamines and nitric oxide, and is essential for placentation, angiogenesis, and growth. Maternal plasma arginine concentrations are found to be lower in pregnancies complicated by fetal growth restriction, and arginine supplementation in later pregnancy is reported to increase birth weight. We measured arginine and the metabolites asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in the amniotic fluid obtained in pregnancy weeks 13 to 15 from 363 pregnancies with a documented normal outcome and related the concentrations to birth weight, length, and head circumference. Arginine was higher in the amniotic fluid from female (mean 40.8 (SD 10.6) µmol/L) compared to male fetuses (37.4 (SD 11.2) µmol/L, p = 0.003). Despite the gender difference, arginine in the amniotic fluid from gestational weeks 13-15 was the strongest predictor for birth weight, length, and head circumference. ADMA was a strong predictor for birth weight and length, SDMA for birth weight, while Arg/ADMA and Arg/SDMA only predicted head circumference in multiple linear regression models. Due to increased arginine demands, pregnancy is considered a state of relative arginine deficiency. Our findings reflect the importance of a good maternal arginine status in early pregnancy, an observation that should be evaluated in an intervention study.
A Case Study in User Support for Managing OpenSim Based Multi User Learning Environments
ERIC Educational Resources Information Center
Perera, Indika; Miller, Alan; Allison, Colin
2017-01-01
Immersive 3D Multi User Learning Environments (MULE) have shown sufficient success to warrant their consideration as a mainstream educational paradigm. These are based on 3D Multi User Virtual Environment platforms (MUVE), and although they have been used for various innovative educational projects their complex permission systems and large…
A joint precoding scheme for indoor downlink multi-user MIMO VLC systems
NASA Astrophysics Data System (ADS)
Zhao, Qiong; Fan, Yangyu; Kang, Bochao
2017-11-01
In this study, we aim to improve the system performance and reduce the implementation complexity of precoding scheme for visible light communication (VLC) systems. By incorporating the power-method algorithm and the block diagonalization (BD) algorithm, we propose a joint precoding scheme for indoor downlink multi-user multi-input-multi-output (MU-MIMO) VLC systems. In this scheme, we apply the BD algorithm to eliminate the co-channel interference (CCI) among users firstly. Secondly, the power-method algorithm is used to search the precoding weight for each user based on the optimal criterion of signal to interference plus noise ratio (SINR) maximization. Finally, the optical power restrictions of VLC systems are taken into account to constrain the precoding weight matrix. Comprehensive computer simulations in two scenarios indicate that the proposed scheme always has better bit error rate (BER) performance and lower computation complexity than that of the traditional scheme.
Improvements in the chronology, geochemistry and correlation techniques of tephra in Antarctic ice
NASA Astrophysics Data System (ADS)
Iverson, N. A.; Dunbar, N. W.; McIntosh, W. C.; Pearce, N. J.; Kyle, P. R.
2013-12-01
Visible and crypto tephra layers found in West Antarctic ice provide an excellent record of Antarctic volcanism over the past 100ka. Tephra layers are deposited almost instantaneously across wide areas creating horizons that, if found in several locations, provide 'pinning points' to adjust ice time scales that may otherwise be lacking detailed chronology. Individual tephra layers can have distinct chemical fingerprints allowing them to correlate over great distances. Advances in sample preparation, geochemical analyses (major and trace elements) of fine grained tephra and higher precision 40Ar/39Ar dating of young (<100ka) proximal volcanic deposits are improving an already established tephra record in West Antarctica. Forty three of the potential hundreds of silicate layers found in a recently drilled deep West Antarctic Ice Sheet Divide core (WDC06A) have been analyzed for major elements and a subset for trace elements. Of these layers, at least 16 are homogenous tephra that could be correlated to other ice cores (e.g. Siple Dome, SDMA) and/or to source volcanoes found throughout Antarctica and even extra-continental eruptions (e.g. Sub-Antarctic islands and South America). Combining ice core tephra with those exposed in blue ice areas provide more locations to correlate widespread eruptions. For example, a period of heightened eruptive activity at Mt. Berlin, West Antarctica between 24 and 28ka produced a set of tephra layers that are found in WDC06A and SDMA ice cores, as well as at a nearby blue ice area at Mt. Moulton (BIT-151 and BIT-152). Possible correlative tephra layers are found at ice ages of 26.4, 26.9 and 28.8ka in WDC06A and 26.5, 27.0, and 28.7ka in SDMA cores. The geochemical similarities of major elements in these layers mean that ongoing trace element analyses will be vital to decipher the sequence of events during this phase of activity at Mt. Berlin. Sample WDC06A-2767.117 (ice age of 28.6×1.0ka) appears to correlate to blue ice tephra BIT-152 and to tephra layer SDMA-5683 (ice age of 28.5ka). This tephra layer also appears to be present in blue ice at Mt. Terra Nova on Ross Island, 1400km away, suggesting that it may be a possible to link ice cores in East Antarctica (e.g. Talos Dome and Law Dome). The amount of feldspar in ice core tephra is typically too small to be directly dated by 40Ar/39Ar method, making it very important to geochemically correlate these layers to proximal deposits where more and larger feldspar can be sampled. The correlation of WDC06A-2767.117 to the coarse, proximal BIT-152 provides one such link. The New Mexico Geochronology Research Lab (NMGRL) has two new multi-collector ARGUS VI mass spectrometers that can provide single crystal laser fusion ages that are approximately an order of magnitude more precise than the previous determinations. With these advancements in analytical technology, we hope to improve precision on 'pinning points' in the deep ice cores where annual layer counting becomes less precise.
A Multi-Agent System for Intelligent Online Education.
ERIC Educational Resources Information Center
O'Riordan, Colm; Griffith, Josephine
1999-01-01
Describes the system architecture of an intelligent Web-based education system that includes user modeling agents, information filtering agents for automatic information gathering, and the multi-agent interaction. Discusses information management; user interaction; support for collaborative peer-peer learning; implementation; testing; and future…
Wilson Tang, Wai Hong; Tong, Wilson; Shrestha, Kevin; Wang, Zeneng; Levison, Bruce S.; Delfraino, Brian; Hu, Bo; Troughton, Richard W.; Klein, Allan L.; Hazen, Stanley L.
2008-01-01
Aims To investigate the association of arginine methylation with myocardial function and prognosis in chronic systolic heart failure patients. Methods and results Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA), as well as N-mono-methylarginine (MMA) and methyl-lysine, were simultaneously measured by tandem mass spectrometry in 132 patients with chronic systolic heart failure with echocardiographic evaluation and follow-up. Increasing ADMA and SDMA levels were associated with elevated natriuretic peptide levels (both P < 0.001), and increasing SDMA levels were associated with worsening renal function (P < 0.001). Higher plasma levels of methylated arginine metabolites (but not methyl-lysine) were associated with the presence of left ventricular (LV) diastolic dysfunction (E/septal E′, Spearman's r = 0.31–0.36, P < 0.001). Patients taking beta-blockers had lower ADMA levels than those not taking beta-blockers [0.42 (0.33, 0.50) vs. 0.51 (0.40, 0.58), P < 0.001]. Only increasing ADMA levels were associated with advanced right ventricular (RV) systolic dysfunction. Elevated ADMA levels remained a consistent independent predictor of adverse clinical events (hazard ratio = 1.64, 95% CI: 1.20–2.22, P = 0.002). Conclusion In chronic systolic heart failure, accumulation of methylated arginine metabolites is associated with the presence of LV diastolic dysfunction. Among the methylated derivatives of arginine, ADMA provides the strongest independent prediction of disease progression and adverse long-term outcomes. PMID:18687662
Hadjikyriacou, Andrea; Yang, Yanzhong; Espejo, Alexsandra; Bedford, Mark T.; Clarke, Steven G.
2015-01-01
Human protein arginine methyltransferase (PRMT) 9 symmetrically dimethylates arginine residues on splicing factor SF3B2 (SAP145) and has been functionally linked to the regulation of alternative splicing of pre-mRNA. Site-directed mutagenesis studies on this enzyme and its substrate had revealed essential unique residues in the double E loop and the importance of the C-terminal duplicated methyltransferase domain. In contrast to what had been observed with other PRMTs and their physiological substrates, a peptide containing the methylatable Arg-508 of SF3B2 was not recognized by PRMT9 in vitro. Although amino acid substitutions of residues surrounding Arg-508 had no great effect on PRMT9 recognition of SF3B2, moving the arginine residue within this sequence abolished methylation. PRMT9 and PRMT5 are the only known mammalian enzymes capable of forming symmetric dimethylarginine (SDMA) residues as type II PRMTs. We demonstrate here that the specificity of these enzymes for their substrates is distinct and not redundant. The loss of PRMT5 activity in mouse embryo fibroblasts results in almost complete loss of SDMA, suggesting that PRMT5 is the primary SDMA-forming enzyme in these cells. PRMT9, with its duplicated methyltransferase domain and conserved sequence in the double E loop, appears to have a unique structure and specificity among PRMTs for methylating SF3B2 and potentially other polypeptides. PMID:25979344
Tutoring and Multi-Agent Systems: Modeling from Experiences
ERIC Educational Resources Information Center
Bennane, Abdellah
2010-01-01
Tutoring systems become complex and are offering varieties of pedagogical software as course modules, exercises, simulators, systems online or offline, for single user or multi-user. This complexity motivates new forms and approaches to the design and the modelling. Studies and research in this field introduce emergent concepts that allow the…
A Distributed Ambient Intelligence Based Multi-Agent System for Alzheimer Health Care
NASA Astrophysics Data System (ADS)
Tapia, Dante I.; RodríGuez, Sara; Corchado, Juan M.
This chapter presents ALZ-MAS (Alzheimer multi-agent system), an ambient intelligence (AmI)-based multi-agent system aimed at enhancing the assistance and health care for Alzheimer patients. The system makes use of several context-aware technologies that allow it to automatically obtain information from users and the environment in an evenly distributed way, focusing on the characteristics of ubiquity, awareness, intelligence, mobility, etc., all of which are concepts defined by AmI. ALZ-MAS makes use of a services oriented multi-agent architecture, called flexible user and services oriented multi-agent architecture, to distribute resources and enhance its performance. It is demonstrated that a SOA approach is adequate to build distributed and highly dynamic AmI-based multi-agent systems.
Pedersen, L G; Tarnow, I; Olsen, L H; Teerlink, T; Pedersen, H D
2006-06-01
Asymmetric dimethylarginine (ADMA) is a marker of various cardiovascular diseases in man. The aim of the present study was to test if Cavalier King Charles Spaniels (CKCS) with varying degrees of mitral regurgitation (MR) had increased plasma concentration of ADMA and furthermore, characterize the plasma level of ADMA and symmetric dimethylarginine (SDMA) in normal dogs. Seventy-six dogs were included (44 CKCS and 32 dogs of other breeds). The CKCS had various degrees of MR, whereas the remaining dogs had either no or minimal MR. Apart from cardiac murmurs, no dogs showed signs of cardiac or systematic disease. The degree of MR had no significant influence on ADMA (P = 0.33). Body weight was directly associated with ADMA (P = 0.0004) and creatinine was directly associated with SDMA (P<0.0001). Furthermore, the plasma concentration of ADMA was three to four times higher than found in healthy humans.
NASA Astrophysics Data System (ADS)
Ikeda, Sei; Sato, Tomokazu; Kanbara, Masayuki; Yokoya, Naokazu
2004-05-01
Technology that enables users to experience a remote site virtually is called telepresence. A telepresence system using real environment images is expected to be used in the field of entertainment, medicine, education and so on. This paper describes a novel telepresence system which enables users to walk through a photorealistic virtualized environment by actual walking. To realize such a system, a wide-angle high-resolution movie is projected on an immersive multi-screen display to present users the virtualized environments and a treadmill is controlled according to detected user's locomotion. In this study, we use an omnidirectional multi-camera system to acquire images real outdoor scene. The proposed system provides users with rich sense of walking in a remote site.
MTVis: tree exploration using a multitouch interface
NASA Astrophysics Data System (ADS)
Andrews, David; Teoh, Soon Tee
2010-01-01
We present MTVis, a multi-touch interactive tree visualization system. The multi-touch interface display hardware is built using the LED-LP technology, and the tree layout is based on RINGS, but enhanced with multitouch interactions. We describe the features of the system, and how the multi-touch interface enhances the user's experience in exploring the tree data structure. In particular, the multi-touch interface allows the user to simultaneously control two child nodes of the root, and rotate them so that some nodes are magnified, while preserving the layout of the tree. We also describe the other meaninful touch screen gestures the users can use to intuitively explore the tree.
Sandqvist, Anna; Schneede, Jörn; Kylhammar, David; Henrohn, Dan; Lundgren, Jakob; Hedeland, Mikael; Bondesson, Ulf; Rådegran, Göran; Wikström, Gerhard
2018-03-01
Pulmonary arterial hypertension (PAH) is a life-threatening condition, characterized by an imbalance of vasoactive substances and remodeling of pulmonary vasculature. Nitric oxide, formed from L-arginine, is essential for homeostasis and smooth muscle cell relaxation in PAH. Our aim was to compare plasma concentrations of L-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) in PAH compared to left ventricular systolic dysfunction (LVSD) and healthy subjects. This was an observational, multicenter study comparing 21 patients with PAH to 14 patients with LVSD and 27 healthy subjects. Physical examinations were obtained and blood samples were collected. Plasma levels of ADMA, SDMA, L-arginine, L-ornithine, and L-citrulline were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Plasma levels of ADMA and SDMA were higher, whereas L-arginine and L-arginine/ADMA ratio were lower in PAH patients compared to healthy subjects (p < 0.001). Patients with PAH also had lower levels of L-arginine than patients with LVSD (p < 0.05). L-Arginine correlated to 6 min walking distance (6MWD) (r s = 0.58, p = 0.006) and L-arginine/ADMA correlated to WHO functional class (r s = -0.46, p = 0.043) in PAH. In conclusion, L-arginine levels were significantly lower in treatment naïve PAH patients compared to patients with LVSD. Furthermore, L-arginine correlated with 6MWD in PAH. L-arginine may provide useful information in differentiating PAH from LVSD.
Jain, Kanishk; Warmack, Rebeccah A.; Stavropoulos, Peter
2016-01-01
In the family of protein arginine methyltransferases (PRMTs) that predominantly generate either asymmetric or symmetric dimethylarginine (SDMA), PRMT7 is unique in producing solely monomethylarginine (MMA) products. The type of methylation on histones and other proteins dictates changes in gene expression, and numerous studies have linked altered profiles of methyl marks with disease phenotypes. Given the importance of specific inhibitor development, it is crucial to understand the mechanisms by which PRMT product specificity is conferred. We have focused our attention on active-site residues of PRMT7 from the protozoan Trypanosoma brucei. We have designed 26 single and double mutations in the active site, including residues in the Glu-Xaa8-Glu (double E) loop and the Met-Gln-Trp sequence of the canonical Thr-His-Trp (THW) loop known to interact with the methyl-accepting substrate arginine. Analysis of the reaction products by high resolution cation exchange chromatography combined with the knowledge of PRMT crystal structures suggests a model where the size of two distinct subregions in the active site determines PRMT7 product specificity. A dual mutation of Glu-181 to Asp in the double E loop and Gln-329 to Ala in the canonical THW loop enables the enzyme to produce SDMA. Consistent with our model, the mutation of Cys-431 to His in the THW loop of human PRMT9 shifts its product specificity from SDMA toward MMA. Together with previous results, these findings provide a structural basis and a general model for product specificity in PRMTs, which will be useful for the rational design of specific PRMT inhibitors. PMID:27387499
Structure and function of large arteries in hypertension in relation to oxidative stress markers.
Klima, Łukasz; Kawecka-Jaszcz, Kalina; Stolarz-Skrzypek, Katarzyna; Menne, Jan; Fijorek, Kamil; Olszanecka, Agnieszka; Wojciechowska, Wiktoria; Bilo, Grzegorz; Czarnecka, Danuta
2013-01-01
The relationship between hypertension and oxidative stress remains unexplained. Nevertheless, it is well established that reactive oxygen species have an influence on the arterial wall, endothelial function and therefore determine blood pressure. The evaluation of selected oxidative stress markers in hypertensive patients and an assessment of the relationship between oxidative stress markers and the arterial structure and function. We also aimed to investigate whether the influence of oxidative stress on remodelling of arteries, their structural and functional changes is independent of hypertension or is related to hypertension. Altogether 217 subjects (114 female, 103 male) were enrolled from hypertensive families. The mean age was 45.5 ± 16 years, and the group included 155 hypertensives. In every subject, the pulse wave velocity and intima-media thickness (IMT) in carotid arteries were measured as well as selected oxidative stress markers such as asymmetric dimethylarginin (ADMA), symmetric dimethylarginin (SDMA), advanced oxidation protein products (AOPP) and oxidised low density lipoproteins (ox-LDL). The results of multivariate analysis show that in hypertensive patients: the ADMA level increased with increasing peripheral pulse pressure (b = 0.003; p < 0.001), and AOPP was related to higher carotid IMT (b = 0.91; p = 0.036). In normotensive subjects, the following associations were found: between ADMA and central pulse pressure (b = 0.006; p = 0.008), between SDMA and the peripheral augmentation index (b = -0.03; p = 0.014), between AOPP and the peripheral augmentation index (b = 0.011; p = 0.04), and between ox-LDL/LDL ratio and the peripheral augmentation index (b = -0.025; p = 0.004). The SDMA/ADMA ratio was associated with estimated glomerular filtration rate in both groups (b = -0.0061; p < 0.0001 and b = -0.005; p < 0.017, respectively). In hypertensives, we observed a relation with peripheral pulse pressure (b = -0.0067; p = 0.0143). Moreover, in normotensives there was an association between the SDMA/ADMA ratio and uric acid (b = 1.3629; p = 0.046). We found that the influence of oxidative stress on the structure and function of large arteries was independent of hypertension. Therefore oxidative stress may play a significant role in the development of arterial stiffness. Higher oxidative stress is associated with more advanced arterial remodelling in hypertension.
A Multi-User Microcomputer System for Small Libraries.
ERIC Educational Resources Information Center
Leggate, Peter
1988-01-01
Describes the development of Bookshelf, a multi-user microcomputer system for small libraries that uses an integrated software package. The discussion covers the design parameters of the package, which were based on a survey of seven small libraries, and some characteristics of the software. (three notes with references) (CLB)
NASA Astrophysics Data System (ADS)
Lee, Seokhee; Lee, Kiyoung; Kim, Man Bae; Kim, JongWon
2005-11-01
In this paper, we propose a design of multi-view stereoscopic HD video transmission system based on MPEG-21 Digital Item Adaptation (DIA). It focuses on the compatibility and scalability to meet various user preferences and terminal capabilities. There exist a large variety of multi-view 3D HD video types according to the methods for acquisition, display, and processing. By following the MPEG-21 DIA framework, the multi-view stereoscopic HD video is adapted according to user feedback. A user can be served multi-view stereoscopic video which corresponds with his or her preferences and terminal capabilities. In our preliminary prototype, we verify that the proposed design can support two deferent types of display device (stereoscopic and auto-stereoscopic) and switching viewpoints between two available viewpoints.
Jain, Kanishk; Warmack, Rebeccah A; Debler, Erik W; Hadjikyriacou, Andrea; Stavropoulos, Peter; Clarke, Steven G
2016-08-26
In the family of protein arginine methyltransferases (PRMTs) that predominantly generate either asymmetric or symmetric dimethylarginine (SDMA), PRMT7 is unique in producing solely monomethylarginine (MMA) products. The type of methylation on histones and other proteins dictates changes in gene expression, and numerous studies have linked altered profiles of methyl marks with disease phenotypes. Given the importance of specific inhibitor development, it is crucial to understand the mechanisms by which PRMT product specificity is conferred. We have focused our attention on active-site residues of PRMT7 from the protozoan Trypanosoma brucei We have designed 26 single and double mutations in the active site, including residues in the Glu-Xaa8-Glu (double E) loop and the Met-Gln-Trp sequence of the canonical Thr-His-Trp (THW) loop known to interact with the methyl-accepting substrate arginine. Analysis of the reaction products by high resolution cation exchange chromatography combined with the knowledge of PRMT crystal structures suggests a model where the size of two distinct subregions in the active site determines PRMT7 product specificity. A dual mutation of Glu-181 to Asp in the double E loop and Gln-329 to Ala in the canonical THW loop enables the enzyme to produce SDMA. Consistent with our model, the mutation of Cys-431 to His in the THW loop of human PRMT9 shifts its product specificity from SDMA toward MMA. Together with previous results, these findings provide a structural basis and a general model for product specificity in PRMTs, which will be useful for the rational design of specific PRMT inhibitors. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Sm protein methylation is dispensable for snRNP assembly in Drosophila melanogaster.
Gonsalvez, Graydon B; Praveen, Kavita; Hicks, Amanda J; Tian, Liping; Matera, A Gregory
2008-05-01
Sm proteins form stable ribonucleoprotein (RNP) complexes with small nuclear (sn)RNAs and are core components of the eukaryotic spliceosome. In vivo, the assembly of Sm proteins onto snRNAs requires the survival motor neurons (SMN) complex. Several reports have shown that SMN protein binds with high affinity to symmetric dimethylarginine (sDMA) residues present on the C-terminal tails of SmB, SmD1, and SmD3. This post-translational modification is thought to play a crucial role in snRNP assembly. In human cells, two distinct protein arginine methyltransferases (PRMT5 and PRMT7) are required for snRNP biogenesis. However, in Drosophila, loss of Dart5 (the fruit fly PRMT5 ortholog) has little effect on snRNP assembly, and homozygous mutants are completely viable. To resolve these apparent differences, we examined this topic in detail and found that Drosophila Sm proteins are also methylated by two methyltransferases, Dart5/PRMT5 and Dart7/PRMT7. Unlike dart5, we found that dart7 is an essential gene. However, the lethality associated with loss of Dart7 protein is apparently unrelated to defects in snRNP assembly. To conclusively test the requirement for sDMA modification of Sm proteins in Drosophila snRNP assembly, we constructed a fly strain that exclusively expresses an isoform of SmD1 that cannot be sDMA modified. Interestingly, these flies were viable, and snRNP assays revealed no defects in comparison to wild type. In contrast, dart5 mutants displayed a strong synthetic lethal phenotype in the presence of a hypomorphic Smn mutation. We therefore conclude that dart5 is required for viability when SMN is limiting.
Scandurra, I; Hägglund, M; Koch, S
2008-08-01
This paper presents a new multi-disciplinary method for user needs analysis and requirements specification in the context of health information systems based on established theories from the fields of participatory design and computer supported cooperative work (CSCW). Whereas conventional methods imply a separate, sequential needs analysis for each profession, the "multi-disciplinary thematic seminar" (MdTS) method uses a collaborative design process. Application of the method in elderly homecare resulted in prototypes that were well adapted to the intended user groups. Vital information in the points of intersection between different care professions was elicited and a holistic view of the entire care process was obtained. Health informatics-usability specialists and clinical domain experts are necessary to apply the method. Although user needs acquisition can be time-consuming, MdTS was perceived to efficiently identify in-context user needs, and transformed these directly into requirements specifications. Consequently the method was perceived to expedite the entire ICT implementation process.
Developing Access Control Model of Web OLAP over Trusted and Collaborative Data Warehouses
NASA Astrophysics Data System (ADS)
Fugkeaw, Somchart; Mitrpanont, Jarernsri L.; Manpanpanich, Piyawit; Juntapremjitt, Sekpon
This paper proposes the design and development of Role- based Access Control (RBAC) model for the Single Sign-On (SSO) Web-OLAP query spanning over multiple data warehouses (DWs). The model is based on PKI Authentication and Privilege Management Infrastructure (PMI); it presents a binding model of RBAC authorization based on dimension privilege specified in attribute certificate (AC) and user identification. Particularly, the way of attribute mapping between DW user authentication and privilege of dimensional access is illustrated. In our approach, we apply the multi-agent system to automate flexible and effective management of user authentication, role delegation as well as system accountability. Finally, the paper culminates in the prototype system A-COLD (Access Control of web-OLAP over multiple DWs) that incorporates the OLAP features and authentication and authorization enforcement in the multi-user and multi-data warehouse environment.
Users matter : multi-agent systems model of high performance computing cluster users.
DOE Office of Scientific and Technical Information (OSTI.GOV)
North, M. J.; Hood, C. S.; Decision and Information Sciences
2005-01-01
High performance computing clusters have been a critical resource for computational science for over a decade and have more recently become integral to large-scale industrial analysis. Despite their well-specified components, the aggregate behavior of clusters is poorly understood. The difficulties arise from complicated interactions between cluster components during operation. These interactions have been studied by many researchers, some of whom have identified the need for holistic multi-scale modeling that simultaneously includes network level, operating system level, process level, and user level behaviors. Each of these levels presents its own modeling challenges, but the user level is the most complex duemore » to the adaptability of human beings. In this vein, there are several major user modeling goals, namely descriptive modeling, predictive modeling and automated weakness discovery. This study shows how multi-agent techniques were used to simulate a large-scale computing cluster at each of these levels.« less
Space station operations task force. Panel 2 report: Ground operations and support systems
NASA Technical Reports Server (NTRS)
1987-01-01
The Ground Operations Concept embodied in this report provides for safe multi-user utilization of the Space Station, eases user integration, and gives users autonomy and flexibility. It provides for meaningful multi-national participation while protecting U.S. interests. The concept also supports continued space operations technology development by maintaining NASA expertise and enabling technology evolution. Given attention here are pre/post flight operations, logistics, sustaining engineering/configuration management, transportation services/rescue, and information systems and communication.
ERIC Educational Resources Information Center
Babu, Rakesh; Singh, Rahul
2013-01-01
This paper presents a novel task-oriented, user-centered, multi-method evaluation (TUME) technique and shows how it is useful in providing a more complete, practical and solution-oriented assessment of the accessibility and usability of Learning Management Systems (LMS) for blind and visually impaired (BVI) students. Novel components of TUME…
Pilot users in agile development processes: motivational factors.
Johannessen, Liv Karen; Gammon, Deede
2010-01-01
Despite a wealth of research on user participation, few studies offer insights into how to involve multi-organizational users in agile development methods. This paper is a case study of user involvement in developing a system for electronic laboratory requisitions using agile methodologies in a multi-organizational context. Building on an interpretive approach, we illuminate questions such as: How does collaboration between users and developers evolve and how might it be improved? What key motivational aspects are at play when users volunteer and continue contributing in the face of considerable added burdens? The study highlights how agile methods in themselves appear to facilitate mutually motivating collaboration between user groups and developers. Lessons learned for leveraging the advantages of agile development processes include acknowledging the substantial and ongoing contributions of users and their roles as co-designers of the system.
Design of Instant Messaging System of Multi-language E-commerce Platform
NASA Astrophysics Data System (ADS)
Yang, Heng; Chen, Xinyi; Li, Jiajia; Cao, Yaru
2017-09-01
This paper aims at researching the message system in the instant messaging system based on the multi-language e-commerce platform in order to design the instant messaging system in multi-language environment and exhibit the national characteristics based information as well as applying national languages to e-commerce. In order to develop beautiful and friendly system interface for the front end of the message system and reduce the development cost, the mature jQuery framework is adopted in this paper. The high-performance server Tomcat is adopted at the back end to process user requests, and MySQL database is adopted for data storage to persistently store user data, and meanwhile Oracle database is adopted as the message buffer for system optimization. Moreover, AJAX technology is adopted for the client to actively pull the newest data from the server at the specified time. In practical application, the system has strong reliability, good expansibility, short response time, high system throughput capacity and high user concurrency.
Distributed Compressive CSIT Estimation and Feedback for FDD Multi-User Massive MIMO Systems
NASA Astrophysics Data System (ADS)
Rao, Xiongbin; Lau, Vincent K. N.
2014-06-01
To fully utilize the spatial multiplexing gains or array gains of massive MIMO, the channel state information must be obtained at the transmitter side (CSIT). However, conventional CSIT estimation approaches are not suitable for FDD massive MIMO systems because of the overwhelming training and feedback overhead. In this paper, we consider multi-user massive MIMO systems and deploy the compressive sensing (CS) technique to reduce the training as well as the feedback overhead in the CSIT estimation. The multi-user massive MIMO systems exhibits a hidden joint sparsity structure in the user channel matrices due to the shared local scatterers in the physical propagation environment. As such, instead of naively applying the conventional CS to the CSIT estimation, we propose a distributed compressive CSIT estimation scheme so that the compressed measurements are observed at the users locally, while the CSIT recovery is performed at the base station jointly. A joint orthogonal matching pursuit recovery algorithm is proposed to perform the CSIT recovery, with the capability of exploiting the hidden joint sparsity in the user channel matrices. We analyze the obtained CSIT quality in terms of the normalized mean absolute error, and through the closed-form expressions, we obtain simple insights into how the joint channel sparsity can be exploited to improve the CSIT recovery performance.
A joint swarm intelligence algorithm for multi-user detection in MIMO-OFDM system
NASA Astrophysics Data System (ADS)
Hu, Fengye; Du, Dakun; Zhang, Peng; Wang, Zhijun
2014-11-01
In the multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) system, traditional multi-user detection (MUD) algorithms that usually used to suppress multiple access interference are difficult to balance system detection performance and the complexity of the algorithm. To solve this problem, this paper proposes a joint swarm intelligence algorithm called Ant Colony and Particle Swarm Optimisation (AC-PSO) by integrating particle swarm optimisation (PSO) and ant colony optimisation (ACO) algorithms. According to simulation results, it has been shown that, with low computational complexity, the MUD for the MIMO-OFDM system based on AC-PSO algorithm gains comparable MUD performance with maximum likelihood algorithm. Thus, the proposed AC-PSO algorithm provides a satisfactory trade-off between computational complexity and detection performance.
A multi-user real time inventorying system for radioactive materials: a networking approach.
Mehta, S; Bandyopadhyay, D; Hoory, S
1998-01-01
A computerized system for radioisotope management and real time inventory coordinated across a large organization is reported. It handles hundreds of individual users and their separate inventory records. Use of highly efficient computer network and database technologies makes it possible to accept, maintain, and furnish all records related to receipt, usage, and disposal of the radioactive materials for the users separately and collectively. The system's central processor is an HP-9000/800 G60 RISC server and users from across the organization use their personal computers to login to this server using the TCP/IP networking protocol, which makes distributed use of the system possible. Radioisotope decay is automatically calculated by the program, so that it can make the up-to-date radioisotope inventory data of an entire institution available immediately. The system is specifically designed to allow use by large numbers of users (about 300) and accommodates high volumes of data input and retrieval without compromising simplicity and accuracy. Overall, it is an example of a true multi-user, on-line, relational database information system that makes the functioning of a radiation safety department efficient.
CAI System with Multi-Media Text Through Web Browser for NC Lathe Programming
NASA Astrophysics Data System (ADS)
Mizugaki, Yoshio; Kikkawa, Koichi; Mizui, Masahiko; Kamijo, Keisuke
A new Computer Aided Instruction (CAI) system for NC lathe programming has been developed with use of multi-media texts including movies, animations, pictures, sound and texts through Web browser. Although many CAI systems developed previously for NC programming consist of text-based instructions, it is difficult for beginners to learn NC programming with use of them. In the developed CAI system, multi-media texts are adopted for the help of users' understanding, and it is available through Web browser anytime and anywhere. Also the error log is automatically recorded for the future references. According to the NC programming coded by a user, the movement of the NC lathe is animated and shown in the monitor screen in front of the user. If its movement causes the collision between a cutting tool and the lathe, some sound and the caution remark are generated. If the user makes mistakes some times at a certain stage in learning NC, the corresponding suggestion is shown in the form of movies, animations, and so forth. By using the multimedia texts, users' attention is kept concentrated during a training course. In this paper, the configuration of the CAI system is explained and the actual procedures for users to learn the NC programming are also explained too. Some beginners tested this CAI system and their results are illustrated and discussed from the viewpoint of the efficiency and usefulness of this CAI system. A brief conclusion is also mentioned.
Alteration and Implementation of the CP/M-86 Operating System for a Multi-User Environment.
1982-12-01
THE CP/M-86 OPERATING SYSTEM FOR A MULTI-USER ENVIRONMENT by Thomas V. Almquist and David S. Stevens C-, December 1982 ,LU Thesis Advisor : U. R. Kodres...tool$ 044, robo O0eA 6^900091 Approved for public release; distribution unlimited Alteration and Implementation of the CP/M-86 Operating System for a...SCIENCE IN COMPUTER SCIENCE from the NAVAL POSTGRADUATE SCHOOL December 1982 Authors: Approved by: ..... .. . . . . . . . . Thesis Advisor Second
NASA Astrophysics Data System (ADS)
Lu, Meilian; Yang, Dong; Zhou, Xing
2013-03-01
Based on the analysis of the requirements of conversation history storage in CPM (Converged IP Messaging) system, a Multi-views storage model and access methods of conversation history are proposed. The storage model separates logical views from physical storage and divides the storage into system managed region and user managed region. It simultaneously supports conversation view, system pre-defined view and user-defined view of storage. The rationality and feasibility of multi-view presentation, the physical storage model and access methods are validated through the implemented prototype. It proves that, this proposal has good scalability, which will help to optimize the physical data storage structure and improve storage performance.
Extreme C2 and Multi-Touch, Multi-User Collaborative User Interfaces
2008-06-01
Organization: Office of the Chief Engineer , Space and Naval Warfare Systems Center Charleston Address: PO Box 190022 N. Charleston, SC 29419 843...collaborative development technique can increase the adaptability and quality of software, something of high value in the complex domain of enterprise...concept to C2 should be able to produce similar benefits for planning in military operations, particularly complex, multi- faceted operations. This
Introducing ORACLE: Library Processing in a Multi-User Environment.
ERIC Educational Resources Information Center
Queensland Library Board, Brisbane (Australia).
Currently being developed by the State Library of Queensland, Australia, ORACLE (On-Line Retrieval of Acquisitions, Cataloguing, and Circulation Details for Library Enquiries) is a computerized library system designed to provide rapid processing of library materials in a multi-user environment. It is based on the Australian MARC format and fully…
NASA Astrophysics Data System (ADS)
Lee, Seungwon; Park, Ilkwon; Kim, Manbae; Byun, Hyeran
2006-10-01
As digital broadcasting technologies have been rapidly progressed, users' expectations for realistic and interactive broadcasting services also have been increased. As one of such services, 3D multi-view broadcasting has received much attention recently. In general, all the view sequences acquired at the server are transmitted to the client. Then, the user can select a part of views or all the views according to display capabilities. However, this kind of system requires high processing power of the server as well as the client, thus posing a difficulty in practical applications. To overcome this problem, a relatively simple method is to transmit only two view-sequences requested by the client in order to deliver a stereoscopic video. In this system, effective communication between the server and the client is one of important aspects. In this paper, we propose an efficient multi-view system that transmits two view-sequences and their depth maps according to user's request. The view selection process is integrated into MPEG-21 DIA (Digital Item Adaptation) so that our system is compatible to MPEG-21 multimedia framework. DIA is generally composed of resource adaptation and descriptor adaptation. It is one of merits that SVA (stereoscopic video adaptation) descriptors defined in DIA standard are used to deliver users' preferences and device capabilities. Furthermore, multi-view descriptions related to multi-view camera and system are newly introduced. The syntax of the descriptions and their elements is represented in XML (eXtensible Markup Language) schema. If the client requests an adapted descriptor (e.g., view numbers) to the server, then the server sends its associated view sequences. Finally, we present a method which can reduce user's visual discomfort that might occur while viewing stereoscopic video. This phenomenon happens when view changes as well as when a stereoscopic image produces excessive disparity caused by a large baseline between two cameras. To solve for the former, IVR (intermediate view reconstruction) is employed for smooth transition between two stereoscopic view sequences. As well, a disparity adjustment scheme is used for the latter. Finally, from the implementation of testbed and the experiments, we can show the valuables and possibilities of our system.
Milewski, Krzysztof; Bogacińska-Karaś, Małgorzata; Fręśko, Inez; Hilgier, Wojciech; Jaźwiec, Radosław; Albrecht, Jan; Zielińska, Magdalena
2017-11-02
Previously we had shown that ammonia stimulates nitric oxide (NO) synthesis in astrocytes by increasing the uptake of the precursor amino acid, arginine via the heteromeric arginine/glutamine transporter y⁺LAT2. Ammonia also increases the concentration in the brain of the endogenous inhibitor of nitric oxide synthases (NOS), asymmetric dimethylarginine (ADMA), but distribution of ADMA surplus between the intraastrocytic and extracellular compartments of the brain has not been studied. Here we tested the hypothesis that ammonia modulates the distribution of ADMA and its analog symmetric dimethylarginine (SDMA) between the two compartments of the brain by competition with arginine for the y⁺LAT2 transporter. In extension of the hypothesis we analyzed the ADMA/Arg interaction in endothelial cells forming the blood-brain barrier. We measured by high-performance liquid chromatography (HPLC) and mass spectrometry (MS) technique the concentration of arginine, ADMA and SDMA in cultured cortical astrocytes and in a rat brain endothelial cell line (RBE-4) treated with ammonia and the effect of silencing the expression of a gene coding y⁺LAT2. We also tested the expression of ADMA metabolism enzymes: protein arginine methyltransferase (PRMT) and dimethylarginine dimethyl aminohydrolase (DDAH) and arginine uptake to astrocytes. Treatment for 48 h with 5 mM ammonia led to an almost 50% reduction of ADMA and SDMA concentration in both cell types, and the effect in astrocytes was substantially attenuated by silencing of the Slc7a6 gene. Moreover, the y⁺LAT2-dependent component of ammonia-evoked arginine uptake in astrocytes was reduced in the presence of ADMA in the medium. Our results suggest that increased ADMA efflux mediated by upregulated y⁺LAT2 may be a mechanism by which ammonia interferes with intra-astrocytic (and possibly intra-endothelial cell) ADMA content and subsequently, NO synthesis in both cell types.
NASA Technical Reports Server (NTRS)
Dominick, Wayne D. (Editor); Liu, I-Hsiung
1985-01-01
The currently developed multi-level language interfaces of information systems are generally designed for experienced users. These interfaces commonly ignore the nature and needs of the largest user group, i.e., casual users. This research identifies the importance of natural language query system research within information storage and retrieval system development; addresses the topics of developing such a query system; and finally, proposes a framework for the development of natural language query systems in order to facilitate the communication between casual users and information storage and retrieval systems.
DEEP SPACE: High Resolution VR Platform for Multi-user Interactive Narratives
NASA Astrophysics Data System (ADS)
Kuka, Daniela; Elias, Oliver; Martins, Ronald; Lindinger, Christopher; Pramböck, Andreas; Jalsovec, Andreas; Maresch, Pascal; Hörtner, Horst; Brandl, Peter
DEEP SPACE is a large-scale platform for interactive, stereoscopic and high resolution content. The spatial and the system design of DEEP SPACE are facing constraints of CAVETM-like systems in respect to multi-user interactive storytelling. To be used as research platform and as public exhibition space for many people, DEEP SPACE is capable to process interactive, stereoscopic applications on two projection walls with a size of 16 by 9 meters and a resolution of four times 1080p (4K) each. The processed applications are ranging from Virtual Reality (VR)-environments to 3D-movies to computationally intensive 2D-productions. In this paper, we are describing DEEP SPACE as an experimental VR platform for multi-user interactive storytelling. We are focusing on the system design relevant for the platform, including the integration of the Apple iPod Touch technology as VR control, and a special case study that is demonstrating the research efforts in the field of multi-user interactive storytelling. The described case study, entitled "Papyrate's Island", provides a prototypical scenario of how physical drawings may impact on digital narratives. In this special case, DEEP SPACE helps us to explore the hypothesis that drawing, a primordial human creative skill, gives us access to entirely new creative possibilities in the domain of interactive storytelling.
Quiz Making Activities Using the Multi-Mouse Quiz System in an Elementary School
ERIC Educational Resources Information Center
Zhou, Juan; Mori, Mikihiko; Ueda, Hiroshi; Kita, Hajime
2013-01-01
The Multi-Mouse Quiz System is an application used to treat quizzes in a classroom or other learning environment. The system comprises the Multi Mouse Quiz (MMQ) and MMQEditor. The MMQ is an application of Single Display Groupware (SDG), which enables multiple users to answer quizzes by connecting several mice to an ordinary computer. The…
1982-10-01
spent in preparing this document. 00. EXECUTIVE SUMMARY The O’Hare Runway Configuration Management System (CMS) is an interactive multi-user computer ...MITRE Washington’s Computer Center. Currently, CMS is housed in an IBM 4341 computer with VM/SP operating system. CMS employs the IBM’s Display...iV 0O, o 0 .r4L /~ wA 0U 00 00 0 w vi O’Hare, it will operate on a dedicated mini- computer which permits multi-tasking (that is, multiple users
NASA Astrophysics Data System (ADS)
Sun, Yuan; Bhattacherjee, Anol
2011-11-01
Information technology (IT) usage within organisations is a multi-level phenomenon that is influenced by individual-level and organisational-level variables. Yet, current theories, such as the unified theory of acceptance and use of technology, describe IT usage as solely an individual-level phenomenon. This article postulates a model of organisational IT usage that integrates salient organisational-level variables such as user training, top management support and technical support within an individual-level model to postulate a multi-level model of IT usage. The multi-level model was then empirically validated using multi-level data collected from 128 end users and 26 managers in 26 firms in China regarding their use of enterprise resource planning systems and analysed using the multi-level structural equation modelling (MSEM) technique. We demonstrate the utility of MSEM analysis of multi-level data relative to the more common structural equation modelling analysis of single-level data and show how single-level data can be aggregated to approximate multi-level analysis when multi-level data collection is not possible. We hope that this article will motivate future scholars to employ multi-level data and multi-level analysis for understanding organisational phenomena that are truly multi-level in nature.
Best kept secrets ... Source Data Systems, Inc. (SDS).
Andrew, W F
1991-03-01
The SDS/MEDNET system is a cost-effective option for small- to medium-size hospitals (up to 400 beds). The parameter-driven system lets users control operations with only occasional SDS assistance. A full application set, available for modular selection to reduce upfront costs while facilitating steady growth and protecting client investment, is adaptable to multi-facility environments. The industry-standard, Intel-based multi-user processors, network communications and protocols assure high efficiency, low-cost solutions independent of any one hardware vendor. Sustained growth in both client base and product offerings point to a high level of responsiveness and healthcare industry commitment. Corporate emphasis on user involvement and open systems integration assures clients of leading-edge capabilities. SDS/MEDNET will be a strong contender in selected marketing environments.
NASA Astrophysics Data System (ADS)
Zhao, Wei-hu; Zhao, Jing; Zhao, Shang-hong; Li, Yong-jun; Wang, Xiang; Dong, Yi; Dong, Chen
2013-08-01
Optical satellite communication with the advantages of broadband, large capacity and low power consuming broke the bottleneck of the traditional microwave satellite communication. The formation of the Space-based Information System with the technology of high performance optical inter-satellite communication and the realization of global seamless coverage and mobile terminal accessing are the necessary trend of the development of optical satellite communication. Considering the resources, missions and restraints of Data Relay Satellite Optical Communication System, a model of optical communication resources scheduling is established and a scheduling algorithm based on artificial intelligent optimization is put forwarded. According to the multi-relay-satellite, multi-user-satellite, multi-optical-antenna and multi-mission with several priority weights, the resources are scheduled reasonable by the operation: "Ascertain Current Mission Scheduling Time" and "Refresh Latter Mission Time-Window". The priority weight is considered as the parameter of the fitness function and the scheduling project is optimized by the Genetic Algorithm. The simulation scenarios including 3 relay satellites with 6 optical antennas, 12 user satellites and 30 missions, the simulation result reveals that the algorithm obtain satisfactory results in both efficiency and performance and resources scheduling model and the optimization algorithm are suitable in multi-relay-satellite, multi-user-satellite, and multi-optical-antenna recourses scheduling problem.
A novel framework to alleviate the sparsity problem in context-aware recommender systems
NASA Astrophysics Data System (ADS)
Yu, Penghua; Lin, Lanfen; Wang, Jing
2017-04-01
Recommender systems have become indispensable for services in the era of big data. To improve accuracy and satisfaction, context-aware recommender systems (CARSs) attempt to incorporate contextual information into recommendations. Typically, valid and influential contexts are determined in advance by domain experts or feature selection approaches. Most studies have focused on utilizing the unitary context due to the differences between various contexts. Meanwhile, multi-dimensional contexts will aggravate the sparsity problem, which means that the user preference matrix would become extremely sparse. Consequently, there are not enough or even no preferences in most multi-dimensional conditions. In this paper, we propose a novel framework to alleviate the sparsity issue for CARSs, especially when multi-dimensional contextual variables are adopted. Motivated by the intuition that the overall preferences tend to show similarities among specific groups of users and conditions, we first explore to construct one contextual profile for each contextual condition. In order to further identify those user and context subgroups automatically and simultaneously, we apply a co-clustering algorithm. Furthermore, we expand user preferences in a given contextual condition with the identified user and context clusters. Finally, we perform recommendations based on expanded preferences. Extensive experiments demonstrate the effectiveness of the proposed framework.
NASA Technical Reports Server (NTRS)
Benford, Steve; Bowers, John; Fahlen, Lennart E.; Greenhalgh, Chris; Snowdon, Dave
1994-01-01
This paper explores the issue of user embodiment within collaborative virtual environments. By user embodiment we mean the provision of users with appropriate body images so as to represent them to others and also to themselves. By collaborative virtual environments we mean multi-user virtual reality systems which support cooperative work (although we argue that the results of our exploration may also be applied to other kinds of collaborative systems). The main part of the paper identifies a list of embodiment design issues including: presence, location, identity, activity, availability, history of activity, viewpoint, action point, gesture, facial expression, voluntary versus involuntary expression, degree of presence, reflecting capabilities, manipulating the user's view of others, representation across multiple media, autonomous and distributed body parts, truthfulness and efficiency. Following this, we show how these issues are reflected in our own DIVE and MASSIVE prototype collaborative virtual environments.
Action tagging in a multi-user indoor environment for behavioural analysis purposes.
Guerra, Claudio; Bianchi, Valentina; De Munari, Ilaria; Ciampolini, Paolo
2015-01-01
EU population is getting older, so that ICT-based solutions are expected to provide support in the challenges implied by the demographic change. At the University of Parma an AAL (Ambient Assisted Living) system, named CARDEA, has been developed. In this paper a new feature of the system is introduced, in which environmental and personal (i.e., wearable) sensors coexist, providing an accurate picture of the user's activity and needs. Environmental devices may greatly help in performing activity recognition and behavioral analysis tasks. However, in a multi-user environment, this implies the need of attributing environmental sensors outcome to a specific user, i.e., identifying the user when he performs a task detected by an environmental device. We implemented such an "action tagging" feature, based on information fusion, within the CARDEA environment, as an inexpensive, alternative solution to the problematic issue of indoor locationing.
Zero-forcing pre-coding for MIMO WiMAX transceivers: Performance analysis and implementation issues
NASA Astrophysics Data System (ADS)
Cattoni, A. F.; Le Moullec, Y.; Sacchi, C.
Next generation wireless communication networks are expected to achieve ever increasing data rates. Multi-User Multiple-Input-Multiple-Output (MU-MIMO) is a key technique to obtain the expected performance, because such a technique combines the high capacity achievable using MIMO channel with the benefits of space division multiple access. In MU-MIMO systems, the base stations transmit signals to two or more users over the same channel, for this reason every user can experience inter-user interference. This paper provides a capacity analysis of an online, interference-based pre-coding algorithm able to mitigate the multi-user interference of the MU-MIMO systems in the context of a realistic WiMAX application scenario. Simulation results show that pre-coding can significantly increase the channel capacity. Furthermore, the paper presents several feasibility considerations for implementation of the analyzed technique in a possible FPGA-based software defined radio.
Multilevel Evaluation Systems Project. Final Report.
ERIC Educational Resources Information Center
Herman, Joan L.
Several studies were conducted in 1987 by the Multilevel Evaluation Systems Project, which focuses on developing a model for a multi-purpose, multi-user evaluation system to facilitate educational decision making and evaluation. The project model emphasizes on-going integrated assessment of individuals, classes, and programs using a variety of…
Ju, Bin; Qian, Yuntao; Ye, Minchao; Ni, Rong; Zhu, Chenxi
2015-01-01
Predicting what items will be selected by a target user in the future is an important function for recommendation systems. Matrix factorization techniques have been shown to achieve good performance on temporal rating-type data, but little is known about temporal item selection data. In this paper, we developed a unified model that combines Multi-task Non-negative Matrix Factorization and Linear Dynamical Systems to capture the evolution of user preferences. Specifically, user and item features are projected into latent factor space by factoring co-occurrence matrices into a common basis item-factor matrix and multiple factor-user matrices. Moreover, we represented both within and between relationships of multiple factor-user matrices using a state transition matrix to capture the changes in user preferences over time. The experiments show that our proposed algorithm outperforms the other algorithms on two real datasets, which were extracted from Netflix movies and Last.fm music. Furthermore, our model provides a novel dynamic topic model for tracking the evolution of the behavior of a user over time. PMID:26270539
Ju, Bin; Qian, Yuntao; Ye, Minchao; Ni, Rong; Zhu, Chenxi
2015-01-01
Predicting what items will be selected by a target user in the future is an important function for recommendation systems. Matrix factorization techniques have been shown to achieve good performance on temporal rating-type data, but little is known about temporal item selection data. In this paper, we developed a unified model that combines Multi-task Non-negative Matrix Factorization and Linear Dynamical Systems to capture the evolution of user preferences. Specifically, user and item features are projected into latent factor space by factoring co-occurrence matrices into a common basis item-factor matrix and multiple factor-user matrices. Moreover, we represented both within and between relationships of multiple factor-user matrices using a state transition matrix to capture the changes in user preferences over time. The experiments show that our proposed algorithm outperforms the other algorithms on two real datasets, which were extracted from Netflix movies and Last.fm music. Furthermore, our model provides a novel dynamic topic model for tracking the evolution of the behavior of a user over time.
A Robotic Coach Architecture for Elder Care (ROCARE) Based on Multi-user Engagement Models
Fan, Jing; Bian, Dayi; Zheng, Zhi; Beuscher, Linda; Newhouse, Paul A.; Mion, Lorraine C.; Sarkar, Nilanjan
2017-01-01
The aging population with its concomitant medical conditions, physical and cognitive impairments, at a time of strained resources, establishes the urgent need to explore advanced technologies that may enhance function and quality of life. Recently, robotic technology, especially socially assistive robotics has been investigated to address the physical, cognitive, and social needs of older adults. Most system to date have predominantly focused on one-on-one human robot interaction (HRI). In this paper, we present a multi-user engagement-based robotic coach system architecture (ROCARE). ROCARE is capable of administering both one-on-one and multi-user HRI, providing implicit and explicit channels of communication, and individualized activity management for long-term engagement. Two preliminary feasibility studies, a one-on-one interaction and a triadic interaction with two humans and a robot, were conducted and the results indicated potential usefulness and acceptance by older adults, with and without cognitive impairment. PMID:28113672
A Robotic Coach Architecture for Elder Care (ROCARE) Based on Multi-User Engagement Models.
Fan, Jing; Bian, Dayi; Zheng, Zhi; Beuscher, Linda; Newhouse, Paul A; Mion, Lorraine C; Sarkar, Nilanjan
2017-08-01
The aging population with its concomitant medical conditions, physical and cognitive impairments, at a time of strained resources, establishes the urgent need to explore advanced technologies that may enhance function and quality of life. Recently, robotic technology, especially socially assistive robotics has been investigated to address the physical, cognitive, and social needs of older adults. Most system to date have predominantly focused on one-on-one human robot interaction (HRI). In this paper, we present a multi-user engagement-based robotic coach system architecture (ROCARE). ROCARE is capable of administering both one-on-one and multi-user HRI, providing implicit and explicit channels of communication, and individualized activity management for long-term engagement. Two preliminary feasibility studies, a one-on-one interaction and a triadic interaction with two humans and a robot, were conducted and the results indicated potential usefulness and acceptance by older adults, with and without cognitive impairment.
Scientific Visualization of Radio Astronomy Data using Gesture Interaction
NASA Astrophysics Data System (ADS)
Mulumba, P.; Gain, J.; Marais, P.; Woudt, P.
2015-09-01
MeerKAT in South Africa (Meer = More Karoo Array Telescope) will require software to help visualize, interpret and interact with multidimensional data. While visualization of multi-dimensional data is a well explored topic, little work has been published on the design of intuitive interfaces to such systems. More specifically, the use of non-traditional interfaces (such as motion tracking and multi-touch) has not been widely investigated within the context of visualizing astronomy data. We hypothesize that a natural user interface would allow for easier data exploration which would in turn lead to certain kinds of visualizations (volumetric, multidimensional). To this end, we have developed a multi-platform scientific visualization system for FITS spectral data cubes using VTK (Visualization Toolkit) and a natural user interface to explore the interaction between a gesture input device and multidimensional data space. Our system supports visual transformations (translation, rotation and scaling) as well as sub-volume extraction and arbitrary slicing of 3D volumetric data. These tasks were implemented across three prototypes aimed at exploring different interaction strategies: standard (mouse/keyboard) interaction, volumetric gesture tracking (Leap Motion controller) and multi-touch interaction (multi-touch monitor). A Heuristic Evaluation revealed that the volumetric gesture tracking prototype shows great promise for interfacing with the depth component (z-axis) of 3D volumetric space across multiple transformations. However, this is limited by users needing to remember the required gestures. In comparison, the touch-based gesture navigation is typically more familiar to users as these gestures were engineered from standard multi-touch actions. Future work will address a complete usability test to evaluate and compare the different interaction modalities against the different visualization tasks.
NASA Technical Reports Server (NTRS)
1973-01-01
The Data Base Administrator User's Guide for the NASA Aerospace Safety information system is presented. The subjects discussed are: (1) multi-terminal tasking, (2) data base executive, (3) utilities, (4) maintenance, and (5) update mode functions.
Kahan, Deborah; Leszcz, Molyn; O'Campo, Patricia; Hwang, Stephen W; Wasylenki, Donald A; Kurdyak, Paul; Wise Harris, Deborah; Gozdzik, Agnes; Stergiopoulos, Vicky
2016-04-27
Addressing the needs of frequent users of emergency departments (EDs) is a health system priority in many jurisdictions. This study describes stakeholder perspectives on the implementation of a multi-organizational brief intervention designed to support integration and continuity of care for frequent ED users with mental health and addictions problems, focusing on perceived barriers and facilitators to early implementation in a large urban centre. Coordinating Access to Care from Hospital Emergency Departments (CATCH-ED) is a brief case management intervention bridging hospital, primary and community care for frequent ED users experiencing mental illness and addictions. To examine barriers and facilitators to early implementation of this multi-organizational intervention, between July and October 2012, 47 stakeholders, including direct service providers, managers and administrators participated in 32 semi-structured qualitative interviews and one focus group exploring their experience with the intervention and factors that helped or hindered successful early implementation. Qualitative data were analyzed using thematic analysis. Stakeholders valued the intervention and its potential to support continuity of care for this population. Service delivery system factors, including organizational capacity and a history of collaborative relationships across the healthcare continuum, and support system factors, such as training and supervision, emerged as key facilitators of program implementation. Operational challenges included early low program referral rates, management of a multi-organizational initiative, variable adherence to the model among participating organizations, and scant access to specialty psychiatric resources. Factors contributing to these challenges included lack of dedicated staff in the ED and limited local system capacity to support this population, and insufficient training and technical assistance available to participating organizations. A multi-organizational brief intervention is an acceptable model to support integration of hospital, primary and community care for frequent ED users. The study highlights the importance of early implementation evaluation to identify potential solutions to implementation barriers that may be applicable to many jurisdictions.
The Use of a UNIX-Based Workstation in the Information Systems Laboratory
1989-03-01
system. The conclusions of the research and the resulting recommendations are presented in Chapter III. These recommendations include how to manage...required to run the program on a new system, these should not be significant changes. 2. Processing Environment The UNIX processing environment is...interactive with multi-tasking and multi-user capabilities. Multi-tasking refers to the fact that many programs can be run concurrently. This capability
NASA Astrophysics Data System (ADS)
Ding, Zhongan; Gao, Chen; Yan, Shengteng; Yang, Canrong
2017-10-01
The power user electric energy data acquire system (PUEEDAS) is an important part of smart grid. This paper builds a multi-objective optimization model for the performance of the PUEEADS from the point of view of the combination of the comprehensive benefits and cost. Meanwhile, the Chebyshev decomposition approach is used to decompose the multi-objective optimization problem. We design a MOEA/D evolutionary algorithm to solve the problem. By analyzing the Pareto optimal solution set of multi-objective optimization problem and comparing it with the monitoring value to grasp the direction of optimizing the performance of the PUEEDAS. Finally, an example is designed for specific analysis.
NASA Astrophysics Data System (ADS)
Lu, Xiaodong; Mori, Kinji
The market and users' requirements have been rapidly changing and diversified. Under these heterogeneous and dynamic situations, not only the system structure itself, but also the accessible information services would be changed constantly. To cope with the continuously changing conditions of service provision and utilization, Faded Information Field (FIF) has been proposed, which is a agent-based distributed information service system architecture. In the case of a mono-service request, the system is designed to improve users' access time and preserve load balancing through the information structure. However, with interdependent requests of multi-service increasing, adaptability and timeliness have to be assured by the system. In this paper, the relationship that exists among the correlated services and the users' preferences for separate and integrated services is clarified. Based on these factors, the autonomous preference-aware information services integration technology to provide one-stop service for users multi-service requests is proposed. As compared to the conventional system, we show that proposed technology is able to reduce the total access time.
Effect of the transdermal low-level laser therapy on endothelial function.
Szymczyszyn, Alicja; Doroszko, Adrian; Szahidewicz-Krupska, Ewa; Rola, Piotr; Gutherc, Radosław; Jasiczek, Jakub; Mazur, Grzegorz; Derkacz, Arkadiusz
2016-09-01
The effect of low-level laser therapy (LLLT) on the cardiovascular system is not fully established. Since the endothelium is an important endocrine element, establishing the mechanisms of LLLT action is an important issue.The aim of the study was to evaluate the effect of transdermal LLLT on endothelial function.In this study, healthy volunteers (n = 40, age = 20-40 years) were enrolled. N = 30 (14 female, 16 male, mean age 30 ± 5 years) constituted the laser-irradiated group (LG). The remaining 10 subjects (6 women, 4 men, mean age 28 ± 5 years) constituted the control group (CG). Participants were subjected to LLLT once a day for three consecutive days. Blood for biochemical assessments was drawn before the first irradiation and 24 h after the last session. In the LG, transdermal illumination of radial artery was conducted (a semiconductor laser λ = 808 nm, irradiation 50 mW, energy density 1.6 W/cm(2) and a dose 20 J/day, a total dose of 60 J). Biochemical parameters (reflecting angiogenesis: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), angiostatin; antioxidative status: glutathione (GSH) and the nitric oxide metabolic pathway: symmetric dimethylarginine (SDMA), asymmetric dimethylarginine (ADMA) and L-arginine) were assessed. In the LG, a significant increase in GSH levels and considerable decrease in angiostatin concentration following the LLLT were observed. No significant differences in levels of the VEGF, FGF, SDMA, ADMA were observed.LLLT modifies vascular endothelial function by increasing its antioxidant and angiogenic potential. We found no significant differences in levels of the nitric oxide pathway metabolites within 24 h following the LLLT irradiation.
NASA Technical Reports Server (NTRS)
1973-01-01
The Data Base Administrator User's Guide for the NASA Aerospace Safety Information System is presented. The subjects discussed are: (1) multi-terminal tasking, (2) data base executive, (3) utilities, (4) maintenance, (5) terminal support, and (6) retrieval subsystem.
Multi-pulse frequency shifted (MPFS) multiple access modulation for ultra wideband
Nekoogar, Faranak [San Ramon, CA; Dowla, Farid U [Castro Valley, CA
2012-01-24
The multi-pulse frequency shifted technique uses mutually orthogonal short duration pulses o transmit and receive information in a UWB multiuser communication system. The multiuser system uses the same pulse shape with different frequencies for the reference and data for each user. Different users have a different pulse shape (mutually orthogonal to each other) and different transmit and reference frequencies. At the receiver, the reference pulse is frequency shifted to match the data pulse and a correlation scheme followed by a hard decision block detects the data.
Proportional fair scheduling algorithm based on traffic in satellite communication system
NASA Astrophysics Data System (ADS)
Pan, Cheng-Sheng; Sui, Shi-Long; Liu, Chun-ling; Shi, Yu-Xin
2018-02-01
In the satellite communication network system, in order to solve the problem of low system capacity and user fairness in multi-user access to satellite communication network in the downlink, combined with the characteristics of user data service, an algorithm study on throughput capacity and user fairness scheduling is proposed - Proportional Fairness Algorithm Based on Traffic(B-PF). The algorithm is improved on the basis of the proportional fairness algorithm in the wireless communication system, taking into account the user channel condition and caching traffic information. The user outgoing traffic is considered as the adjustment factor of the scheduling priority and presents the concept of traffic satisfaction. Firstly,the algorithm calculates the priority of the user according to the scheduling algorithm and dispatches the users with the highest priority. Secondly, when a scheduled user is the business satisfied user, the system dispatches the next priority user. The simulation results show that compared with the PF algorithm, B-PF can improve the system throughput, the business satisfaction and fairness.
Regulation of post-translational protein arginine methylation during HeLa cell cycle.
Kim, Chongtae; Lim, Yongchul; Yoo, Byong Chul; Won, Nam Hee; Kim, Sangduk; Kim, Gieun
2010-09-01
Post-translational arginine methylation which modifies protein-arginyl residues by protein arginine methyltransferase (PRMT) was investigated during synchronized HeLa cell cycle. The lysates of cells synchronized at each stage were subjected to one and/or two dimensional electrophoresis followed by Western immunoblot using against anti-asymmetric-dimethyl-arginine (ASYM24), anti-symmetric-dimethyl-arginine (SYM10), and subclasses of PRMTs, including PRMT1, PRMT3, PRMT4 (CARM1), PRMT5, PRMT6, and PRMT7 antibodies. Proteins with approximate molecular masses of 80 kDa, 68 kDa, and 64 kDa, containing asymmetric-dimethyl-arginine (aDMA) were increased at G0/G1 to G1, which lasted until S phase. In addition, 25 kDa protein of symmetric-dimethyl-arginine (sDMA) was also markedly up-regulated from G0/G1 to G1. The levels of PRMT3, PRMT6 and PRMT7 were concurrently increased during the cell cycle. Two-dimensional gel electrophoresis followed by MALDI-TOF-MS was identified as aDMA-80 kDa and aDMA-68 kDa proteins as heterogeneous nuclear ribonucleoprotein R (hnRNPR), aDMA-64 kDa proteins as cleavage stimulation factor 64 kDa subunit (CstF-64), and sDMA-25 kDa protein as triosephosphate isomerase (TPI). The levels of increased aDMA of hnRNPR were reduced, when HeLa cells were transfected with siRNA for PRMT1, and the aDMA of CstF-64 with siRNA for PRMT3, while depletion of PRMT5 down-regulated sDMA of TPI. Protein arginine dimethylations of hnRNPR, CstF-64, and TPI were regulated during HeLa cell cycle by respective PRMTs. These results suggest that regulation of arginine dimethylation of hnRNPR, CstF-64, and TPI at G0/G1 to G1 are most likely to modulate the cellular growth and proliferation in HeLa cell cycle. Copyright © 2010 Elsevier B.V. All rights reserved.
The automated multi-stage substructuring system for NASTRAN
NASA Technical Reports Server (NTRS)
Field, E. I.; Herting, D. N.; Herendeen, D. L.; Hoesly, R. L.
1975-01-01
The substructuring capability developed for eventual installation in Level 16 is now operational in a test version of NASTRAN. Its features are summarized. These include the user-oriented, Case Control type control language, the automated multi-stage matrix processing, the independent direct access data storage facilities, and the static and normal modes solution capabilities. A complete problem analysis sequence is presented with card-by-card description of the user input.
Using component technology to facilitate external software reuse in ground-based planning systems
NASA Technical Reports Server (NTRS)
Chase, A.
2003-01-01
APGEN (Activity Plan GENerator - 314), a multi-mission planning tool, must interface with external software to vest serve its users. AP-GEN's original method for incorporating external software, the User-Defined library mechanism, has been very successful in allowing APGEN users access to external software functionality.
Developing a Software for Fuzzy Group Decision Support System: A Case Study
ERIC Educational Resources Information Center
Baba, A. Fevzi; Kuscu, Dincer; Han, Kerem
2009-01-01
The complex nature and uncertain information in social problems required the emergence of fuzzy decision support systems in social areas. In this paper, we developed user-friendly Fuzzy Group Decision Support Systems (FGDSS) software. The software can be used for multi-purpose decision making processes. It helps the users determine the main and…
Integrating Iris and Signature Traits for Personal Authentication Using User-Specific Weighting
Viriri, Serestina; Tapamo, Jules R.
2012-01-01
Biometric systems based on uni-modal traits are characterized by noisy sensor data, restricted degrees of freedom, non-universality and are susceptible to spoof attacks. Multi-modal biometric systems seek to alleviate some of these drawbacks by providing multiple evidences of the same identity. In this paper, a user-score-based weighting technique for integrating the iris and signature traits is presented. This user-specific weighting technique has proved to be an efficient and effective fusion scheme which increases the authentication accuracy rate of multi-modal biometric systems. The weights are used to indicate the importance of matching scores output by each biometrics trait. The experimental results show that our biometric system based on the integration of iris and signature traits achieve a false rejection rate (FRR) of 0.08% and a false acceptance rate (FAR) of 0.01%. PMID:22666032
Bimanual Interaction with Interscopic Multi-Touch Surfaces
NASA Astrophysics Data System (ADS)
Schöning, Johannes; Steinicke, Frank; Krüger, Antonio; Hinrichs, Klaus; Valkov, Dimitar
Multi-touch interaction has received considerable attention in the last few years, in particular for natural two-dimensional (2D) interaction. However, many application areas deal with three-dimensional (3D) data and require intuitive 3D interaction techniques therefore. Indeed, virtual reality (VR) systems provide sophisticated 3D user interface, but then lack efficient 2D interaction, and are therefore rarely adopted by ordinary users or even by experts. Since multi-touch interfaces represent a good trade-off between intuitive, constrained interaction on a touch surface providing tangible feedback, and unrestricted natural interaction without any instrumentation, they have the potential to form the foundation of the next generation user interface for 2D as well as 3D interaction. In particular, stereoscopic display of 3D data provides an additional depth cue, but until now the challenges and limitations for multi-touch interaction in this context have not been considered. In this paper we present new multi-touch paradigms and interactions that combine both traditional 2D interaction and novel 3D interaction on a touch surface to form a new class of multi-touch systems, which we refer to as interscopic multi-touch surfaces (iMUTS). We discuss iMUTS-based user interfaces that support interaction with 2D content displayed in monoscopic mode and 3D content usually displayed stereoscopically. In order to underline the potential of the proposed iMUTS setup, we have developed and evaluated two example interaction metaphors for different domains. First, we present intuitive navigation techniques for virtual 3D city models, and then we describe a natural metaphor for deforming volumetric datasets in a medical context.
Integration of multi-interface conversion channel using FPGA for modular photonic network
NASA Astrophysics Data System (ADS)
Janicki, Tomasz; Pozniak, Krzysztof T.; Romaniuk, Ryszard S.
2010-09-01
The article discusses the integration of different types of interfaces with FPGA circuits using a reconfigurable communication platform. The solution has been implemented in practice in a single node of a distributed measurement system. Construction of communication platform has been presented with its selected hardware modules, described in VHDL and implemented in FPGA circuits. The graphical user interface (GUI) has been described that allows a user to control the operation of the system. In the final part of the article selected practical solutions have been introduced. The whole measurement system resides on multi-gigabit optical network. The optical network construction is highly modular, reconfigurable and scalable.
Usability Guidelines for Product Recommenders Based on Example Critiquing Research
NASA Astrophysics Data System (ADS)
Pu, Pearl; Faltings, Boi; Chen, Li; Zhang, Jiyong; Viappiani, Paolo
Over the past decade, our group has developed a suite of decision tools based on example critiquing to help users find their preferred products in e-commerce environments. In this chapter, we survey important usability research work relative to example critiquing and summarize the major results by deriving a set of usability guidelines. Our survey is focused on three key interaction activities between the user and the system: the initial preference elicitation process, the preference revision process, and the presentation of the systems recommendation results. To provide a basis for the derivation of the guidelines, we developed a multi-objective framework of three interacting criteria: accuracy, confidence, and effort (ACE). We use this framework to analyze our past work and provide a specific context for each guideline: when the system should maximize its ability to increase users' decision accuracy, when to increase user confidence, and when to minimize the interaction effort for the users. Due to the general nature of this multi-criteria model, the set of guidelines that we propose can be used to ease the usability engineering process of other recommender systems, especially those used in e-commerce environments. The ACE framework presented here is also the first in the field to evaluate the performance of preference-based recommenders from a user-centric point of view.
A power-efficient ZF precoding scheme for multi-user indoor visible light communication systems
NASA Astrophysics Data System (ADS)
Zhao, Qiong; Fan, Yangyu; Deng, Lijun; Kang, Bochao
2017-02-01
In this study, we propose a power-efficient ZF precoding scheme for visible light communication (VLC) downlink multi-user multiple-input-single-output (MU-MISO) systems, which incorporates the zero-forcing (ZF) and the characteristics of VLC systems. The main idea of this scheme is that the channel matrix used to perform pseudoinverse comes from the set of optical Access Points (APs) shared by more than one user, instead of the set of all involved serving APs as the existing ZF precoding schemes often used. By doing this, the waste of power, which is caused by the transmission of one user's data in the un-serving APs, can be avoided. In addition, the size of the channel matrix needs to perform pseudoinverse becomes smaller, which helps to reduce the computation complexity. Simulation results in two scenarios show that the proposed ZF precoding scheme has higher power efficiency, better bit error rate (BER) performance and lower computation complexity compared with traditional ZF precoding schemes.
Design criteria for a PC-based common user interface to remote information systems
NASA Technical Reports Server (NTRS)
Dominick, Wayne D. (Editor); Hall, Philip P.
1984-01-01
A set of design criteria are presented which will allow the implementation of an interface to multiple remote information systems on a microcomputer. The focus of the design description is on providing the user with the functionality required to retrieve, store and manipulate data residing in remote information systems through the utilization of a standardized interface system. The intent is to spare the user from learning the details of retrieval from specific systems while retaining the full capabilities of each system. The system design includes multi-level capabilities to enhance usability by a wide range of users and utilizes microcomputer graphics capabilities where applicable. A data collection subsystem for evaluation purposes is also described.
Multi-factor authentication using quantum communication
Hughes, Richard John; Peterson, Charles Glen; Thrasher, James T.; Nordholt, Jane E.; Yard, Jon T.; Newell, Raymond Thorson; Somma, Rolando D.
2018-02-06
Multi-factor authentication using quantum communication ("QC") includes stages for enrollment and identification. For example, a user enrolls for multi-factor authentication that uses QC with a trusted authority. The trusted authority transmits device factor information associated with a user device (such as a hash function) and user factor information associated with the user (such as an encrypted version of a user password). The user device receives and stores the device factor information and user factor information. For multi-factor authentication that uses QC, the user device retrieves its stored device factor information and user factor information, then transmits the user factor information to the trusted authority, which also retrieves its stored device factor information. The user device and trusted authority use the device factor information and user factor information (more specifically, information such as a user password that is the basis of the user factor information) in multi-factor authentication that uses QC.
Pérez-Pérez, Martín; Glez-Peña, Daniel; Fdez-Riverola, Florentino; Lourenço, Anália
2015-02-01
Document annotation is a key task in the development of Text Mining methods and applications. High quality annotated corpora are invaluable, but their preparation requires a considerable amount of resources and time. Although the existing annotation tools offer good user interaction interfaces to domain experts, project management and quality control abilities are still limited. Therefore, the current work introduces Marky, a new Web-based document annotation tool equipped to manage multi-user and iterative projects, and to evaluate annotation quality throughout the project life cycle. At the core, Marky is a Web application based on the open source CakePHP framework. User interface relies on HTML5 and CSS3 technologies. Rangy library assists in browser-independent implementation of common DOM range and selection tasks, and Ajax and JQuery technologies are used to enhance user-system interaction. Marky grants solid management of inter- and intra-annotator work. Most notably, its annotation tracking system supports systematic and on-demand agreement analysis and annotation amendment. Each annotator may work over documents as usual, but all the annotations made are saved by the tracking system and may be further compared. So, the project administrator is able to evaluate annotation consistency among annotators and across rounds of annotation, while annotators are able to reject or amend subsets of annotations made in previous rounds. As a side effect, the tracking system minimises resource and time consumption. Marky is a novel environment for managing multi-user and iterative document annotation projects. Compared to other tools, Marky offers a similar visually intuitive annotation experience while providing unique means to minimise annotation effort and enforce annotation quality, and therefore corpus consistency. Marky is freely available for non-commercial use at http://sing.ei.uvigo.es/marky. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
MAI-free performance of PMU-OFDM transceiver in time-variant environment
NASA Astrophysics Data System (ADS)
Tadjpour, Layla; Tsai, Shang-Ho; Kuo, C.-C. J.
2005-06-01
An approximately multi-user OFDM transceiver was introduced to reduce the multi-access interference (MAI ) due to the carrier frequency offset (CFO) to a negligible amount via precoding by Tsai, Lin and Kuo. In this work, we investigate the performance of this precoded multi-user (PMU) OFDM system in a time-variant channel environment. We analyze and compare the MAI effect caused by time-variant channels in the PMU-OFDM and the OFDMA systems. Generally speaking, the MAI effect consists of two parts. The first part is due to the loss of orthogonality among subchannels for all users while the second part is due to the CFO effect caused by the Doppler shift. Simulation results show that, although OFDMA outperforms the PMU-OFDM transceiver in a fast time-variant environment without CFO, PMU-OFDM outperforms OFDMA in a slow time-variant channel via the use of M/2 symmetric or anti-symmetric codewords of M Hadamard-Walsh codes.
A Third-Party E-payment Protocol Based on Quantum Multi-proxy Blind Signature
NASA Astrophysics Data System (ADS)
Niu, Xu-Feng; Zhang, Jian-Zhong; Xie, Shu-Cui; Chen, Bu-Qing
2018-05-01
A third-party E-payment protocol is presented in this paper. It is based on quantum multi-proxy blind signature. Adopting the techniques of quantum key distribution, one-time pad and quantum multi-proxy blind signature, our third-party E-payment system could protect user's anonymity as the traditional E-payment systems do, and also have unconditional security which the classical E-payment systems can not provide. Furthermore, compared with the existing quantum E-payment systems, the proposed system could support the E-payment which using the third-party platforms.
ERIC Educational Resources Information Center
Hwang, Wu-Yuin; Su, Jia-Han; Huang, Yueh-Min; Dong, Jian-Jie
2009-01-01
In this paper, the development of an innovative Virtual Manipulatives and Whiteboard (VMW) system is described. The VMW system allowed users to manipulate virtual objects in 3D space and find clues to solve geometry problems. To assist with multi-representation transformation, translucent multimedia whiteboards were used to provide a virtual 3D…
Cabana Multi-User Spaceport Tour of KSC
2017-02-17
Kennedy Space Center Director Bob Cabana speaks to members of the news media on the balcony of Operations Support Building II describing the site's transition from a primarily government-only facility to a premier, multi-user spaceport. In the background is the Vehicle Assembly Building (VAB). Modifications were recently completed in the VAB where new work platforms were installed to support processing of NASA's Space Launch System rocket designed to send the Orion spacecraft on missions beyond low-Earth orbit.
Multi-User Hardware Solutions to Combustion Science ISS Research
NASA Technical Reports Server (NTRS)
Otero, Angel M.
2001-01-01
In response to the budget environment and to expand on the International Space Station (ISS) Fluids and Combustion Facility (FCF) Combustion Integrated Rack (CIR), common hardware approach, the NASA Combustion Science Program shifted focus in 1999 from single investigator PI (Principal Investigator)-specific hardware to multi-user 'Minifacilities'. These mini-facilities would take the CIR common hardware philosophy to the next level. The approach that was developed re-arranged all the investigations in the program into sub-fields of research. Then common requirements within these subfields were used to develop a common system that would then be complemented by a few PI-specific components. The sub-fields of research selected were droplet combustion, solids and fire safety, and gaseous fuels. From these research areas three mini-facilities have sprung: the Multi-user Droplet Combustion Apparatus (MDCA) for droplet research, Flow Enclosure for Novel Investigations in Combustion of Solids (FEANICS) for solids and fire safety, and the Multi-user Gaseous Fuels Apparatus (MGFA) for gaseous fuels. These mini-facilities will develop common Chamber Insert Assemblies (CIA) and diagnostics for the respective investigators complementing the capability provided by CIR. Presently there are four investigators for MDCA, six for FEANICS, and four for MGFA. The goal of these multi-user facilities is to drive the cost per PI down after the initial development investment is made. Each of these mini-facilities will become a fixture of future Combustion Science NASA Research Announcements (NRAs), enabling investigators to propose against an existing capability. Additionally, an investigation is provided the opportunity to enhance the existing capability to bridge the gap between the capability and their specific science requirements. This multi-user development approach will enable the Combustion Science Program to drive cost per investigation down while drastically reducing the time required to go from selection to space flight.
Podium: Ranking Data Using Mixed-Initiative Visual Analytics.
Wall, Emily; Das, Subhajit; Chawla, Ravish; Kalidindi, Bharath; Brown, Eli T; Endert, Alex
2018-01-01
People often rank and order data points as a vital part of making decisions. Multi-attribute ranking systems are a common tool used to make these data-driven decisions. Such systems often take the form of a table-based visualization in which users assign weights to the attributes representing the quantifiable importance of each attribute to a decision, which the system then uses to compute a ranking of the data. However, these systems assume that users are able to quantify their conceptual understanding of how important particular attributes are to a decision. This is not always easy or even possible for users to do. Rather, people often have a more holistic understanding of the data. They form opinions that data point A is better than data point B but do not necessarily know which attributes are important. To address these challenges, we present a visual analytic application to help people rank multi-variate data points. We developed a prototype system, Podium, that allows users to drag rows in the table to rank order data points based on their perception of the relative value of the data. Podium then infers a weighting model using Ranking SVM that satisfies the user's data preferences as closely as possible. Whereas past systems help users understand the relationships between data points based on changes to attribute weights, our approach helps users to understand the attributes that might inform their understanding of the data. We present two usage scenarios to describe some of the potential uses of our proposed technique: (1) understanding which attributes contribute to a user's subjective preferences for data, and (2) deconstructing attributes of importance for existing rankings. Our proposed approach makes powerful machine learning techniques more usable to those who may not have expertise in these areas.
The Evolvable Advanced Multi-Mission Operations System (AMMOS): Making Systems Interoperable
NASA Technical Reports Server (NTRS)
Ko, Adans Y.; Maldague, Pierre F.; Bui, Tung; Lam, Doris T.; McKinney, John C.
2010-01-01
The Advanced Multi-Mission Operations System (AMMOS) provides a common Mission Operation System (MOS) infrastructure to NASA deep space missions. The evolution of AMMOS has been driven by two factors: increasingly challenging requirements from space missions, and the emergence of new IT technology. The work described in this paper focuses on three key tasks related to IT technology requirements: first, to eliminate duplicate functionality; second, to promote the use of loosely coupled application programming interfaces, text based file interfaces, web-based frameworks and integrated Graphical User Interfaces (GUI) to connect users, data, and core functionality; and third, to build, develop, and deploy AMMOS services that are reusable, agile, adaptive to project MOS configurations, and responsive to industrially endorsed information technology standards.
MEMS-Based Communications Systems for Space-Based Applications
NASA Technical Reports Server (NTRS)
DeLosSantos, Hector J.; Brunner, Robert A.; Lam, Juan F.; Hackett, Le Roy H.; Lohr, Ross F., Jr.; Larson, Lawrence E.; Loo, Robert Y.; Matloubian, Mehran; Tangonan, Gregory L.
1995-01-01
As user demand for higher capacity and flexibility in communications satellites increases, new ways to cope with the inherent limitations posed by the prohibitive mass and power consumption, needed to satisfy those requirements, are under investigation. Recent studies suggest that while new satellite architectures are necessary to enable multi-user, multi-data rate, multi-location satellite links, these new architectures will inevitably increase power consumption, and in turn, spacecraft mass, to such an extent that their successful implementation will demand novel lightweight/low power hardware approaches. In this paper, following a brief introduction to the fundamentals of communications satellites, we address the impact of micro-electro-mechanical systems (MEMS) technology, in particular micro-electro-mechanical (MEM) switches to mitigate the above mentioned problems and show that low-loss/wide bandwidth MEM switches will go a long way towards enabling higher capacity and flexibility space-based communications systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anthony L. Crawford
2012-08-01
Natural movements and force feedback are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished in remote and/or hazardous environments, such as hot cells, glove boxes, decommissioning, explosives disarmament, and space to name a few. In order to achieve this end the research presented in this paper has developed an admittance type exoskeleton like multi-fingered haptic hand user interface that secures the user’s palm and provides 3-dimensional force feedback to the user’s fingertips. Atypical to conventional haptic hand user interfaces that limit themselves to integrating the human hand’s characteristics just into the system’smore » mechanical design this system also perpetuates that inspiration into the designed user interface’s controller. This is achieved by manifesting the property differences of manipulation and grasping activities as they pertain to the human hand into a nonlinear master-slave force relationship. The results presented in this paper show that the admittance-type system has sufficient bandwidth that it appears nearly transparent to the user when the user is in free motion and when the system is subjected to a manipulation task, increased performance is achieved using the nonlinear force relationship compared to the traditional linear scaling techniques implemented in the vast majority of systems.« less
UPenn Multi-Robot Unmanned Vehicle System (MAGIC)
2014-05-05
unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 UPenn Multi-Robot Unmanned Vehicle System (MAGIC) AFOSR Final Report PI... user interface, the Strategy/Plan operator allows the system to autonomously task the nearest available UGVs to plan and coordinate their movements and...threats in a dynamic urban environment with minimal human guidance. The custom hardware systems consist of robust and complementary sensors, integrated
Design and implementation of space physics multi-model application integration based on web
NASA Astrophysics Data System (ADS)
Jiang, Wenping; Zou, Ziming
With the development of research on space environment and space science, how to develop network online computing environment of space weather, space environment and space physics models for Chinese scientific community is becoming more and more important in recent years. Currently, There are two software modes on space physics multi-model application integrated system (SPMAIS) such as C/S and B/S. the C/S mode which is traditional and stand-alone, demands a team or workshop from many disciplines and specialties to build their own multi-model application integrated system, that requires the client must be deployed in different physical regions when user visits the integrated system. Thus, this requirement brings two shortcomings: reducing the efficiency of researchers who use the models to compute; inconvenience of accessing the data. Therefore, it is necessary to create a shared network resource access environment which could help users to visit the computing resources of space physics models through the terminal quickly for conducting space science research and forecasting spatial environment. The SPMAIS develops high-performance, first-principles in B/S mode based on computational models of the space environment and uses these models to predict "Space Weather", to understand space mission data and to further our understanding of the solar system. the main goal of space physics multi-model application integration system (SPMAIS) is to provide an easily and convenient user-driven online models operating environment. up to now, the SPMAIS have contained dozens of space environment models , including international AP8/AE8 IGRF T96 models and solar proton prediction model geomagnetic transmission model etc. which are developed by Chinese scientists. another function of SPMAIS is to integrate space observation data sets which offers input data for models online high-speed computing. In this paper, service-oriented architecture (SOA) concept that divides system into independent modules according to different business needs is applied to solve the problem of the independence of the physical space between multiple models. The classic MVC(Model View Controller) software design pattern is concerned to build the architecture of space physics multi-model application integrated system. The JSP+servlet+javabean technology is used to integrate the web application programs of space physics multi-model. It solves the problem of multi-user requesting the same job of model computing and effectively balances each server computing tasks. In addition, we also complete follow tasks: establishing standard graphical user interface based on Java Applet application program; Designing the interface between model computing and model computing results visualization; Realizing three-dimensional network visualization without plug-ins; Using Java3D technology to achieve a three-dimensional network scene interaction; Improved ability to interact with web pages and dynamic execution capabilities, including rendering three-dimensional graphics, fonts and color control. Through the design and implementation of the SPMAIS based on Web, we provide an online computing and application runtime environment of space physics multi-model. The practical application improves that researchers could be benefit from our system in space physics research and engineering applications.
Cabana Multi-User Spaceport Tour of KSC
2017-02-17
Nancy Bray, director of Spaceport Integration and Services at NASA's Kennedy Space Center, speaks to members of the news media on the balcony of Operations Support Building II describing the site's transition from a primarily government-only facility to a premier, multi-user spaceport. In the background is the Vehicle Assembly Building (VAB). Modifications were recently completed in the VAB where new work platforms were installed to support processing of NASA's Space Launch System rocket designed to send the Orion spacecraft on missions beyond low-Earth orbit.
Cabana Multi-User Spaceport Tour of KSC
2017-02-17
Tom Engler, director of Center Planning and Development at NASA's Kennedy Space Center, speaks to members of the news media on the balcony of Operations Support Building II describing the site's transition from a primarily government-only facility to a premier, multi-user spaceport. In the background is the Vehicle Assembly Building (VAB). Modifications were recently completed in the VAB where new work platforms were installed to support processing of NASA's Space Launch System rocket designed to send the Orion spacecraft on missions beyond low-Earth orbit.
Data Aggregation in Multi-Agent Systems in the Presence of Hybrid Faults
ERIC Educational Resources Information Center
Srinivasan, Satish Mahadevan
2010-01-01
Data Aggregation (DA) is a set of functions that provide components of a distributed system access to global information for purposes of network management and user services. With the diverse new capabilities that networks can provide, applicability of DA is growing. DA is useful in dealing with multi-value domain information and often requires…
Context-based user grouping for multi-casting in heterogeneous radio networks
NASA Astrophysics Data System (ADS)
Mannweiler, C.; Klein, A.; Schneider, J.; Schotten, H. D.
2011-08-01
Along with the rise of sophisticated smartphones and smart spaces, the availability of both static and dynamic context information has steadily been increasing in recent years. Due to the popularity of social networks, these data are complemented by profile information about individual users. Making use of this information by classifying users in wireless networks enables targeted content and advertisement delivery as well as optimizing network resources, in particular bandwidth utilization, by facilitating group-based multi-casting. In this paper, we present the design and implementation of a web service for advanced user classification based on user, network, and environmental context information. The service employs simple and advanced clustering algorithms for forming classes of users. Available service functionalities include group formation, context-aware adaptation, and deletion as well as the exposure of group characteristics. Moreover, the results of a performance evaluation, where the service has been integrated in a simulator modeling user behavior in heterogeneous wireless systems, are presented.
Defense AT and L. Volume 44, Number 1
2015-02-01
other cases, a companion program ( user equipment for the satellite Global Positioning System , for example) may be needed to make the system itself...Jeffrey S. Dodge relieved Capt. Patrick W. Smith as program manager for Multi-Mission Tactical Un- manned Aircraft System (PMA-266) on Oct. 16. Capt. James...emphasis on testing vulnerability with respect to potential user casualties …” and is required for “covered systems ,” which include vehicles, weapon
TSX-PLUS MULTI-TASKING UPGRADE FOR THE NICOLET L-11 POWDER DIFFRACTION SYSTEM.
Fitzpatrick, J.; Queen, David L.
1985-01-01
In August of 1982, a single-user, dual-translator, automated powder diffraction system was purchased by the Denver Research Institute for use on project work in the Chemical and Materials Sciences Division. Within a short period of time, the system had already become saturated with users. Scheduling conflicts arose. In view of these problems, an answer was sought in the form of hardware and software changes which would allow many users access to the system simultaneously. A low-cost, minimum impact solution was eventually found. The elements of the solution are reported.
A Two-Stage Composition Method for Danger-Aware Services Based on Context Similarity
NASA Astrophysics Data System (ADS)
Wang, Junbo; Cheng, Zixue; Jing, Lei; Ota, Kaoru; Kansen, Mizuo
Context-aware systems detect user's physical and social contexts based on sensor networks, and provide services that adapt to the user accordingly. Representing, detecting, and managing the contexts are important issues in context-aware systems. Composition of contexts is a useful method for these works, since it can detect a context by automatically composing small pieces of information to discover service. Danger-aware services are a kind of context-aware services which need description of relations between a user and his/her surrounding objects and between users. However when applying the existing composition methods to danger-aware services, they show the following shortcomings that (1) they have not provided an explicit method for representing composition of multi-user' contexts, (2) there is no flexible reasoning mechanism based on similarity of contexts, so that they can just provide services exactly following the predefined context reasoning rules. Therefore, in this paper, we propose a two-stage composition method based on context similarity to solve the above problems. The first stage is composition of the useful information to represent the context for a single user. The second stage is composition of multi-users' contexts to provide services by considering the relation of users. Finally the danger degree of the detected context is computed by using context similarity between the detected context and the predefined context. Context is dynamically represented based on two-stage composition rules and a Situation theory based Ontology, which combines the advantages of Ontology and Situation theory. We implement the system in an indoor ubiquitous environment, and evaluate the system through two experiments with the support of subjects. The experiment results show the method is effective, and the accuracy of danger detection is acceptable to a danger-aware system.
UNIX: A Tool for Information Management.
ERIC Educational Resources Information Center
Frey, Dean
1989-01-01
Describes UNIX, a computer operating system that supports multi-task and multi-user operations. Characteristics that make it especially suitable for library applications are discussed, including a hierarchical file structure and utilities for text processing, database activities, and bibliographic work. Sources of information on hardware…
Villarubia, Gabriel; De Paz, Juan F.; Bajo, Javier
2017-01-01
The use of electric bikes (e-bikes) has grown in popularity, especially in large cities where overcrowding and traffic congestion are common. This paper proposes an intelligent engine management system for e-bikes which uses the information collected from sensors to optimize battery energy and time. The intelligent engine management system consists of a built-in network of sensors in the e-bike, which is used for multi-sensor data fusion; the collected data is analysed and fused and on the basis of this information the system can provide the user with optimal and personalized assistance. The user is given recommendations related to battery consumption, sensors, and other parameters associated with the route travelled, such as duration, speed, or variation in altitude. To provide a user with these recommendations, artificial neural networks are used to estimate speed and consumption for each of the segments of a route. These estimates are incorporated into evolutionary algorithms in order to make the optimizations. A comparative analysis of the results obtained has been conducted for when routes were travelled with and without the optimization system. From the experiments, it is evident that the use of an engine management system results in significant energy and time savings. Moreover, user satisfaction increases as the level of assistance adapts to user behavior and the characteristics of the route. PMID:29088087
De La Iglesia, Daniel H; Villarrubia, Gabriel; De Paz, Juan F; Bajo, Javier
2017-10-31
The use of electric bikes (e-bikes) has grown in popularity, especially in large cities where overcrowding and traffic congestion are common. This paper proposes an intelligent engine management system for e-bikes which uses the information collected from sensors to optimize battery energy and time. The intelligent engine management system consists of a built-in network of sensors in the e-bike, which is used for multi-sensor data fusion; the collected data is analysed and fused and on the basis of this information the system can provide the user with optimal and personalized assistance. The user is given recommendations related to battery consumption, sensors, and other parameters associated with the route travelled, such as duration, speed, or variation in altitude. To provide a user with these recommendations, artificial neural networks are used to estimate speed and consumption for each of the segments of a route. These estimates are incorporated into evolutionary algorithms in order to make the optimizations. A comparative analysis of the results obtained has been conducted for when routes were travelled with and without the optimization system. From the experiments, it is evident that the use of an engine management system results in significant energy and time savings. Moreover, user satisfaction increases as the level of assistance adapts to user behavior and the characteristics of the route.
NASA Technical Reports Server (NTRS)
Dorais, Gregory A.; Nicewarner, Keith
2006-01-01
We present an multi-agent model-based autonomy architecture with monitoring, planning, diagnosis, and execution elements. We discuss an internal spacecraft free-flying robot prototype controlled by an implementation of this architecture and a ground test facility used for development. In addition, we discuss a simplified environment control life support system for the spacecraft domain also controlled by an implementation of this architecture. We discuss adjustable autonomy and how it applies to this architecture. We describe an interface that provides the user situation awareness of both autonomous systems and enables the user to dynamically edit the plans prior to and during execution as well as control these agents at various levels of autonomy. This interface also permits the agents to query the user or request the user to perform tasks to help achieve the commanded goals. We conclude by describing a scenario where these two agents and a human interact to cooperatively detect, diagnose and recover from a simulated spacecraft fault.
Multi-Modal Traveler Information System - Corridor User Needs and Data Exchange Elements
DOT National Transportation Integrated Search
1997-07-30
Intended as a resource for the members of the GCM Deployment Committee, : Architecture Communication and Information Work Group, project managers, system : designers, system developers and system integrators, this Working Paper supports : the design,...
Xu, Qingqing; Xu, Feifei; Liu, Liang; Chen, Yun
2016-09-06
Protein arginine methylation is one of the common post-translational modifications in cellular processes. To date, two isomeric forms of dimethylated arginine have been identified: asymmetric N(G),N(G)-dimethylarginine (aDMA), and symmetric N(G),N'(G)-dimethylarginine (sDMA). Evidence indicated that these isomers can coexist and have different or even opposite functions, with aDMA and sDMA forms of arginine 2 on histone H3 (i.e., H3R2me2a and H3R2me2s) being an example. Thus, specific detection and quantification of each isomeric form is important. Current methods are capable of predicting and detecting thousands of methylarginine sites in proteins, whereas differentiation and stoichiometric measurement of dimethylated protein isomers are still challenging. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)-based targeted proteomics has emerged as a promising technique for site-specific quantification of protein methylation using enzymatic peptides as surrogates of target proteins. However, it should be pointed out that a routine targeted proteomics strategy cannot easily distinguish sDMA- and aDMA-containing surrogate peptides due to their common nature. The estimated amount should be considered as the sum of both arginine dimethylated isomers. In this study, compositional analysis based on a linear algebra algorithm as an add-on to targeted proteomics was employed to quantify H3R2me2a and H3R2me2s (i.e., surrogate peptides of AR(me2a)TK(me1/2)QT and AR(me2s)TK(me1/2)QT). To achieve this simultaneous quantification, a targeted proteomics assay was developed and validated for each isomer first. With the slope and intercept of their calibration curves for each multiple reaction monitoring (MRM) transition, linear algebraic equations were derived. Using a series of mock mixtures consisting of isomers in varying concentrations, the reliability of the method was confirmed. Finally, the H3R2 dimethylation status was analyzed in normal MCF-10A cells, parental drug-sensitive MCF-7/WT cancer cells, and drug-resistant MCF-7/ADR cancer cells. Dimethylated H3R2 was also monitored in MCF-7/WT cells with the treatment of doxorubicin (DOX) for confirmation.
NASA Astrophysics Data System (ADS)
Saito, Shoichi; Uehara, Tetsutaro; Izumi, Yutaka; Kunieda, Yoshitoshi
The VPN (Virtual Private Network) technique becomes more and more popular to protect contents of messages and to achieve secure communication from incidents, such as tapping. However, it grow in usage that a VPN server is used on a sub-network in part of an office-wide network. But, a PPTP system included in Windows operating systems cannot establish nested VPN links. Moreover encrypted communication by VPN hides a user of the VPN connection. Consequently, any administrators of network systems can’t find out the users of the VPN connection via firewall, moreover can’t decide whether if the user is legal or not. In order to solve this problem, we developed a multi step PPTP relay system on a firewall. This system solves all the problems of our previously developed PPTP relay system(1). The new relay system improves security by encrypting through the whole end-to-end communication and abolishing of prior registration of passwords for the next step. Furthermore, transport speed is accelerated, and the restriction of the number of steps on relay is also abolished. By these features the multi step PPTP relay system expands usability.
INSIGHT: RFID and Bluetooth enabled automated space for the blind and visually impaired.
Ganz, Aura; Gandhi, Siddhesh Rajan; Wilson, Carole; Mullett, Gary
2010-01-01
In this paper we introduce INSIGHT, an indoor location tracking and navigation system to help the blind and visually impaired to easily navigate to their chosen destination in a public building. INSIGHT makes use of RFID and Bluetooth technology deployed within the building to locate and track the users. The PDA based user device interacts with INSIGHT server and provides the user navigation instructions in an audio form. The proposed system provides multi-resolution localization of the users, facilitating the provision of accurate navigation instructions when the user is in the vicinity of the RFID tags as well as accommodating a PANIC button which provides navigation instructions when the user is anywhere in the building. Moreover, the system will continuously monitor the zone in which the user walks. This will enable the system to identify if the user is located in the wrong zone of the building which may not lead to the desired destination.
TeleProbe: design and development of an efficient system for telepathology
NASA Astrophysics Data System (ADS)
Ahmed, Wamiq M.; Robinson, J. Paul; Ghafoor, Arif
2005-10-01
This paper describes an internet-based system for telepathology. This system provides support for multiple users and exploits the opportunities for optimization that arise in multi-user environment. Techniques for increasing system responsiveness by improving resource utilization and lowering network traffic are explored. Some of the proposed optimizations include an auto-focus module, client and server side caching, and request reordering. These systems can be an economic solution not only for remote pathology consultation but also for pathology and biology education.
Lakowski, Ted M; Szeitz, András; Pak, Magnolia L; Thomas, Dylan; Vhuiyan, Mynol I; Kotthaus, Joscha; Clement, Bernd; Frankel, Adam
2013-03-27
Protein arginine methylation is one of the epigenetic modifications to proteins that is studied in yeast and is known to be involved in a number of human diseases. All eukaryotes produce Nη-monomethylarginine (ηMMA), asymmetric Nη1, Nη1-dimethylarginine (aDMA), and most produce symmetric Nη1, Nη2-dimethylarginine (sDMA) on proteins, but only yeast produce Nδ-monomethylarginine (δMMA). It has proven difficult to differentiate among all of these methylarginines using mass spectrometry. Accordingly, we demonstrated that the two forms of MMA have indistinguishable primary product ion spectra. However, the secondary product ion spectra of δMMA and ηMMA exhibited distinct patterns of ions. Using incorporation of deuterated methyl-groups in yeast, we determined which secondary product ions were methylated and their structures. Utilizing distinct secondary product ions, a triple quadrupole multiple reaction monitoring cubed (MRM(3)) assay was developed to measure δMMA, ηMMA, sDMA and aDMA derived from hydrolyzed protein. As a proof-of-concept, δMMA and ηMMA were measured using the MRM(3) method in wild type and mutant strains of Saccharomyces cerevisiae and compared to the total MMA measured using an existing assay. The MRM(3) assay represents the only method to directly quantify δMMA and the only method to simultaneously quantify all yeast methylarginines. Copyright © 2013 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yue, Yufei; CHu, Yuzhuo; Guo, Hong
Protein arginine methyltransferases (PRMTs) catalyze the transfer of the methyl group from S-adenosyl-l-methionine (AdoMet) to arginine residues. There are three types of PRMTs (I, II and III) that produce different methylation products, including asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and monomethylarginine (MMA). Since these different methylations can lead to different biological consequences, understanding the origin of product specificity of PRMTs is of considerable interest. In this article, the quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) and free energy simulations are performed to study SDMA catalyzed by the Type II PRMT5 on the basis of experimental observation that the dimethylated productmore » is generated through a distributive fashion. The simulations have identified some important interactions and proton transfers during the catalysis. Similar to the cases involving Type I PRMTs, a conserved Glu residue (Glu435) in PRMT5 is suggested to function as general base catalyst based on the result of the simulations. Moreover, our results show that PRMT5 has an energetic preference for the first methylation on N-1 followed by the second methylation on a different -guanidino nitrogen of arginine (N-2).The first and second methyl transfers are estimated to have free energy barriers of 19-20 and 18-19 kcal/mol respectively. The computer simulations suggest a distinctive catalytic mechanism of symmetric dimethylation that seems to be different from asymmetric dimethylation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bruemmer, David J; Walton, Miles C
Methods and systems for controlling a plurality of robots through a single user interface include at least one robot display window for each of the plurality of robots with the at least one robot display window illustrating one or more conditions of a respective one of the plurality of robots. The user interface further includes at least one robot control window for each of the plurality of robots with the at least one robot control window configured to receive one or more commands for sending to the respective one of the plurality of robots. The user interface further includes amore » multi-robot common window comprised of information received from each of the plurality of robots.« less
The Renin-Angiotensin-Aldosterone System in Greyhounds and Non-Greyhound Dogs.
Martinez, J; Kellogg, C; Iazbik, M C; Couto, C G; Pressler, B M; Hoepf, T M; Radin, M J
2017-07-01
The renin-angiotensin-aldosterone system (RAAS) regulates blood pressure, electrolyte homeostasis, and renal function. Blood pressure, serum sodium concentrations, and urinary albumin excretion are higher in Greyhounds than other purebred and mixed-breed dogs. Alterations in the RAAS in Greyhounds are associated with hemodynamic and clinicopathologic differences observed in the breed. Clinically healthy Greyhound and non-Greyhound dogs consecutively enrolled as blood donors (n = 20/group). Prospective study. Standard chemical analysis was performed on serum and urine. Serum angiotensin-converting enzyme (ACE) activity was determined by fluorometric assay. All other RAAS hormones were determined by radioimmunoassay. Symmetric dimethylarginine (SDMA) was measured by immunoassay. Measurements were compared to blood pressure and urine albumin concentration. Data are presented as mean ± SD or median, range. Serum creatinine (1.5 ± 0.2 vs 1.0 ± 0.1 mg/dL, P < .001), sodium (149, 147-152 vs 148, 146-150 mEq/L, P = .017), and SDMA (16.1 ± 2.9 vs 12.2 ± 1.8 μg/dL, P < .001) were significantly higher in Greyhounds versus non-Greyhounds, respectively. Plasma renin activity (0.69, 0.10-1.93 vs 0.65, 0.27-2.93 ng/mL/h, P = .60) and ACE activity (4.5, 2.1-8.5 vs 4.6, 2.1-11.4 activity/mL; P = .77) were similar between groups and did not correlate with higher systolic pressures and albuminuria in Greyhounds. Plasma aldosterone concentration was significantly lower in Greyhounds versus non-Greyhounds (11, 11-52 vs 15, 11-56 pg/mL, respectively, P = .002). Basal RAAS activation did not differ between healthy Greyhounds and non-Greyhounds. Lower aldosterone concentration in Greyhounds is an appropriate physiologic response to higher serum sodium concentration and blood pressure, suggesting that angiotensin II effects in the renal tubule predominate over those of aldosterone. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Kushniruk, Andre; Senathirajah, Yalini; Borycki, Elizabeth
2017-01-01
The usability and safety of health information systems have become major issues in the design and implementation of useful healthcare IT. In this paper we describe a multi-phased multi-method approach to integrating usability engineering methods into system testing to ensure both usability and safety of healthcare IT upon widespread deployment. The approach involves usability testing followed by clinical simulation (conducted in-situ) and "near-live" recording of user interactions with systems. At key stages in this process, usability problems are identified and rectified forming a usability and technology-induced error "safety net" that catches different types of usability and safety problems prior to releasing systems widely in healthcare settings.
MultiSpec: A Desktop and Online Geospatial Image Data Processing Tool
NASA Astrophysics Data System (ADS)
Biehl, L. L.; Hsu, W. K.; Maud, A. R. M.; Yeh, T. T.
2017-12-01
MultiSpec is an easy to learn and use, freeware image processing tool for interactively analyzing a broad spectrum of geospatial image data, with capabilities such as image display, unsupervised and supervised classification, feature extraction, feature enhancement, and several other functions. Originally developed for Macintosh and Windows desktop computers, it has a community of several thousand users worldwide, including researchers and educators, as a practical and robust solution for analyzing multispectral and hyperspectral remote sensing data in several different file formats. More recently MultiSpec was adapted to run in the HUBzero collaboration platform so that it can be used within a web browser, allowing new user communities to be engaged through science gateways. MultiSpec Online has also been extended to interoperate with other components (e.g., data management) in HUBzero through integration with the geospatial data building blocks (GABBs) project. This integration enables a user to directly launch MultiSpec Online from data that is stored and/or shared in a HUBzero gateway and to save output data from MultiSpec Online to hub storage, allowing data sharing and multi-step workflows without having to move data between different systems. MultiSpec has also been used in K-12 classes for which one example is the GLOBE program (www.globe.gov) and in outreach material such as that provided by the USGS (eros.usgs.gov/educational-activities). MultiSpec Online now provides teachers with another way to use MultiSpec without having to install the desktop tool. Recently MultiSpec Online was used in a geospatial data session with 30-35 middle school students at the Turned Onto Technology and Leadership (TOTAL) Camp in the summers of 2016 and 2017 at Purdue University. The students worked on a flood mapping exercise using Landsat 5 data to learn about land remote sensing using supervised classification techniques. Online documentation is available for MultiSpec (engineering.purdue.edu/ biehl/MultiSpec/) including a reference manual and several tutorials allowing young high-school students through research faculty to learn the basic functions in MultiSpec. Some of the tutorials have been translated to other languages by MultiSpec users.
The ATLAS multi-user upgrade and potential applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mustapha, B.; Nolen, J. A.; Savard, G.
With the recent integration of the CARIBU-EBIS charge breeder into the ATLAS accelerator system to provide for more pure and efficient charge breeding of radioactive beams, a multi-user upgrade of the ATLAS facility is being proposed to serve multiple users simultaneously. ATLAS was the first superconducting ion linac in the world and is the US DOE low-energy Nuclear Physics National User Facility. The proposed upgrade will take advantage of the continuous-wave nature of ATLAS and the pulsed nature of the EBIS charge breeder in order to simultaneously accelerate two beams with very close mass-to-charge ratios; one stable from the existingmore » ECR ion source and one radioactive from the newly commissioned EBIS charge breeder. In addition to enhancing the nuclear physics program, beam extraction at different points along the linac will open up the opportunity for other potential applications; for instance, material irradiation studies at ~ 1 MeV/u and isotope production at ~ 6 MeV/u or at the full ATLAS energy of ~ 15 MeV/u. The concept and proposed implementation of the ATLAS multi-user upgrade will be presented. Future plans to enhance the flexibility of this upgrade will also be presented.« less
The ATLAS multi-user upgrade and potential applications
NASA Astrophysics Data System (ADS)
Mustapha, B.; Nolen, J. A.; Savard, G.; Ostroumov, P. N.
2017-12-01
With the recent integration of the CARIBU-EBIS charge breeder into the ATLAS accelerator system to provide for more pure and efficient charge breeding of radioactive beams, a multi-user upgrade of the ATLAS facility is being proposed to serve multiple users simultaneously. ATLAS was the first superconducting ion linac in the world and is the US DOE low-energy Nuclear Physics National User Facility. The proposed upgrade will take advantage of the continuous-wave nature of ATLAS and the pulsed nature of the EBIS charge breeder in order to simultaneously accelerate two beams with very close mass-to-charge ratios; one stable from the existing ECR ion source and one radioactive from the newly commissioned EBIS charge breeder. In addition to enhancing the nuclear physics program, beam extraction at different points along the linac will open up the opportunity for other potential applications; for instance, material irradiation studies at ~1 MeV/u, isotope production and radiobiological studies at ~6 MeV/u and at the full ATLAS energy of ~15 MeV/u. The concept and proposed implementation of the ATLAS multi-user upgrade will be discussed. Future plans to enhance the flexibility of this upgrade will be presented.
Computer Viruses and Related Threats: A Management Guide.
ERIC Educational Resources Information Center
Wack, John P.; Carnahan, Lisa J.
This document contains guidance for managing the threats of computer viruses, Trojan horses, network worms, etc. and related software along with unauthorized use. It is geared towards managers of end-user groups, managers dealing with multi-user systems, personal computers, and networks. The guidance is general and addresses the vulnerabilities…
NASA Technical Reports Server (NTRS)
Teng, William; Berrick, Steve; Leptuokh, Gregory; Liu, Zhong; Rui, Hualan; Pham, Long; Shen, Suhung; Zhu, Tong
2004-01-01
The Goddard Space Flight Center Earth Sciences Data and Information Services Center (GES DISC) Distributed Active Center (DAAC) is developing an Agricultural Information System (AIS), evolved from an existing TRMM On-line Visualization and Analysis System precipitation and other satellite data products and services. AIS outputs will be ,integrated into existing operational decision support system for global crop monitoring, such as that of the U.N. World Food Program. The ability to use the raw data stored in the GES DAAC archives is highly dependent on having a detailed understanding of the data's internal structure and physical implementation. To gain this understanding is a time-consuming process and not a productive investment of the user's time. This is an especially difficult challenge when users need to deal with multi-sensor data that usually are of different structures and resolutions. The AIS has taken a major step towards meeting this challenge by incorporating an underlying infrastructure, called the GES-DISC Interactive Online Visualization and Analysis Infrastructure or "Giovanni," that integrates various components to support web interfaces that ,allow users to perform interactive analysis on-line without downloading any data. Several instances of the Giovanni-based interface have been or are being created to serve users of TRMM precipitation, MODIS aerosol, and SeaWiFS ocean color data, as well as agricultural applications users. Giovanni-based interfaces are simple to use but powerful. The user selects geophysical ,parameters, area of interest, and time period; and the system generates an output ,on screen in a matter of seconds.
McDonald, Richard; Nelson, Jonathan; Kinzel, Paul; Conaway, Jeffrey S.
2006-01-01
The Multi-Dimensional Surface-Water Modeling System (MD_SWMS) is a Graphical User Interface for surface-water flow and sediment-transport models. The capabilities of MD_SWMS for developing models include: importing raw topography and other ancillary data; building the numerical grid and defining initial and boundary conditions; running simulations; visualizing results; and comparing results with measured data.
Data Model for Multi Hazard Risk Assessment Spatial Support Decision System
NASA Astrophysics Data System (ADS)
Andrejchenko, Vera; Bakker, Wim; van Westen, Cees
2014-05-01
The goal of the CHANGES Spatial Decision Support System is to support end-users in making decisions related to risk reduction measures for areas at risk from multiple hydro-meteorological hazards. The crucial parts in the design of the system are the user requirements, the data model, the data storage and management, and the relationships between the objects in the system. The implementation of the data model is carried out entirely with an open source database management system with a spatial extension. The web application is implemented using open source geospatial technologies with PostGIS as the database, Python for scripting, and Geoserver and javascript libraries for visualization and the client-side user-interface. The model can handle information from different study areas (currently, study areas from France, Romania, Italia and Poland are considered). Furthermore, the data model handles information about administrative units, projects accessible by different types of users, user-defined hazard types (floods, snow avalanches, debris flows, etc.), hazard intensity maps of different return periods, spatial probability maps, elements at risk maps (buildings, land parcels, linear features etc.), economic and population vulnerability information dependent on the hazard type and the type of the element at risk, in the form of vulnerability curves. The system has an inbuilt database of vulnerability curves, but users can also add their own ones. Included in the model is the management of a combination of different scenarios (e.g. related to climate change, land use change or population change) and alternatives (possible risk-reduction measures), as well as data-structures for saving the calculated economic or population loss or exposure per element at risk, aggregation of the loss and exposure using the administrative unit maps, and finally, producing the risk maps. The risk data can be used for cost-benefit analysis (CBA) and multi-criteria evaluation (SMCE). The data model includes data-structures for CBA and SMCE. The model is at the stage where risk and cost-benefit calculations can be stored but the remaining part is currently under development. Multi-criteria information, user management and the relation of these with the rest of the model is our next step. Having a carefully designed data model plays a crucial role in the development of the whole system for rapid development, keeping the data consistent, and in the end, support the end-user in making good decisions in risk-reduction measures related to multiple natural hazards. This work is part of the EU FP7 Marie Curie ITN "CHANGES"project (www.changes-itn.edu)
Uncoordinated MAC for Adaptive Multi Beam Directional Networks: Analysis and Evaluation
2016-08-01
control (MAC) policies for emerging systems that are equipped with fully digital antenna arrays which are capable of adaptive multi-beam directional...Adaptive Beam- forming, Multibeam, Directional Networking, Random Access, Smart Antennas I. INTRODUCTION Fully digital beamforming antenna arrays that...are capable of adaptive multi-beam communications are quickly becoming a reality. These antenna arrays allow users to form multiple simultaneous
Kwon, Min-Seok; Nam, Seungyoon; Lee, Sungyoung; Ahn, Young Zoo; Chang, Hae Ryung; Kim, Yon Hui; Park, Taesung
2017-01-01
The recent creation of enormous, cancer-related “Big Data” public depositories represents a powerful means for understanding tumorigenesis. However, a consistently accurate system for clinically evaluating single/multi-biomarkers remains lacking, and it has been asserted that oft-failed clinical advancement of biomarkers occurs within the very early stages of biomarker assessment. To address these challenges, we developed a clinically testable, web-based tool, CANcer-specific single/multi-biomarker Evaluation System (CANES), to evaluate biomarker effectiveness, across 2,134 whole transcriptome datasets, from 94,147 biological samples (from 18 tumor types). For user-provided single/multi-biomarkers, CANES evaluates the performance of single/multi-biomarker candidates, based on four classification methods, support vector machine, random forest, neural networks, and classification and regression trees. In addition, CANES offers several advantages over earlier analysis tools, including: 1) survival analysis; 2) evaluation of mature miRNAs as markers for user-defined diagnostic or prognostic purposes; and 3) provision of a “pan-cancer” summary view, based on each single marker. We believe that such “landscape” evaluation of single/multi-biomarkers, for diagnostic therapeutic/prognostic decision-making, will be highly valuable for the discovery and “repurposing” of existing biomarkers (and their specific targeted therapies), leading to improved patient therapeutic stratification, a key component of targeted therapy success for the avoidance of therapy resistance. PMID:29050243
Microcomputers in Libraries: The Quiet Revolution.
ERIC Educational Resources Information Center
Boss, Richard
1985-01-01
This article defines three separate categories of microcomputers--personal, desk-top, multi-user devices--and relates storage capabilities (expandability, floppy disks) to library applications. Highlghts include de facto standards, operating systems, database management systems, applications software, circulation control systems, dumb and…
An intelligent multi-media human-computer dialogue system
NASA Technical Reports Server (NTRS)
Neal, J. G.; Bettinger, K. E.; Byoun, J. S.; Dobes, Z.; Thielman, C. Y.
1988-01-01
Sophisticated computer systems are being developed to assist in the human decision-making process for very complex tasks performed under stressful conditions. The human-computer interface is a critical factor in these systems. The human-computer interface should be simple and natural to use, require a minimal learning period, assist the user in accomplishing his task(s) with a minimum of distraction, present output in a form that best conveys information to the user, and reduce cognitive load for the user. In pursuit of this ideal, the Intelligent Multi-Media Interfaces project is devoted to the development of interface technology that integrates speech, natural language text, graphics, and pointing gestures for human-computer dialogues. The objective of the project is to develop interface technology that uses the media/modalities intelligently in a flexible, context-sensitive, and highly integrated manner modelled after the manner in which humans converse in simultaneous coordinated multiple modalities. As part of the project, a knowledge-based interface system, called CUBRICON (CUBRC Intelligent CONversationalist) is being developed as a research prototype. The application domain being used to drive the research is that of military tactical air control.
Storing files in a parallel computing system based on user or application specification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Faibish, Sorin; Bent, John M.; Nick, Jeffrey M.
2016-03-29
Techniques are provided for storing files in a parallel computing system based on a user-specification. A plurality of files generated by a distributed application in a parallel computing system are stored by obtaining a specification from the distributed application indicating how the plurality of files should be stored; and storing one or more of the plurality of files in one or more storage nodes of a multi-tier storage system based on the specification. The plurality of files comprise a plurality of complete files and/or a plurality of sub-files. The specification can optionally be processed by a daemon executing on onemore » or more nodes in a multi-tier storage system. The specification indicates how the plurality of files should be stored, for example, identifying one or more storage nodes where the plurality of files should be stored.« less
AIRSAR Web-Based Data Processing
NASA Technical Reports Server (NTRS)
Chu, Anhua; Van Zyl, Jakob; Kim, Yunjin; Hensley, Scott; Lou, Yunling; Madsen, Soren; Chapman, Bruce; Imel, David; Durden, Stephen; Tung, Wayne
2007-01-01
The AIRSAR automated, Web-based data processing and distribution system is an integrated, end-to-end synthetic aperture radar (SAR) processing system. Designed to function under limited resources and rigorous demands, AIRSAR eliminates operational errors and provides for paperless archiving. Also, it provides a yearly tune-up of the processor on flight missions, as well as quality assurance with new radar modes and anomalous data compensation. The software fully integrates a Web-based SAR data-user request subsystem, a data processing system to automatically generate co-registered multi-frequency images from both polarimetric and interferometric data collection modes in 80/40/20 MHz bandwidth, an automated verification quality assurance subsystem, and an automatic data distribution system for use in the remote-sensor community. Features include Survey Automation Processing in which the software can automatically generate a quick-look image from an entire 90-GB SAR raw data 32-MB/s tape overnight without operator intervention. Also, the software allows product ordering and distribution via a Web-based user request system. To make AIRSAR more user friendly, it has been designed to let users search by entering the desired mission flight line (Missions Searching), or to search for any mission flight line by entering the desired latitude and longitude (Map Searching). For precision image automation processing, the software generates the products according to each data processing request stored in the database via a Queue management system. Users are able to have automatic generation of coregistered multi-frequency images as the software generates polarimetric and/or interferometric SAR data processing in ground and/or slant projection according to user processing requests for one of the 12 radar modes.
Multi-agent integrated password management (MIPM) application secured with encryption
NASA Astrophysics Data System (ADS)
Awang, Norkhushaini; Zukri, Nurul Hidayah Ahmad; Rashid, Nor Aimuni Md; Zulkifli, Zuhri Arafah; Nazri, Nor Afifah Mohd
2017-10-01
Users use weak passwords and reuse them on different websites and applications. Password managers are a solution to store login information for websites and help users log in automatically. This project developed a system that acts as an agent managing passwords. Multi-Agent Integrated Password Management (MIPM) is an application using encryption that provides users with secure storage of their login account information such as their username, emails and passwords. This project was developed on an Android platform with an encryption agent using Java Agent Development Environment (JADE). The purpose of the embedded agents is to act as a third-party software to ease the encryption process, and in the future, the developed encryption agents can form part of the security system. This application can be used by the computer and mobile users. Currently, users log into many applications causing them to use unique passwords to prevent password leaking. The crypto agent handles the encryption process using an Advanced Encryption Standard (AES) 128-bit encryption algorithm. As a whole, MIPM is developed on the Android application to provide a secure platform to store passwords and has high potential to be commercialised for public use.
Navigation Constellation Design Using a Multi-Objective Genetic Algorithm
2015-03-26
programs. This specific tool not only offers high fidelity simulations, but it also offers the visual aid provided by STK . The ability to...MATLAB and STK . STK is a program that allows users to model, analyze, and visualize space systems. Users can create objects such as satellites and...position dilution of precision (PDOP) and system cost. This thesis utilized Satellite Tool Kit ( STK ) to calculate PDOP values of navigation
Distributed user interfaces for clinical ubiquitous computing applications.
Bång, Magnus; Larsson, Anders; Berglund, Erik; Eriksson, Henrik
2005-08-01
Ubiquitous computing with multiple interaction devices requires new interface models that support user-specific modifications to applications and facilitate the fast development of active workspaces. We have developed NOSTOS, a computer-augmented work environment for clinical personnel to explore new user interface paradigms for ubiquitous computing. NOSTOS uses several devices such as digital pens, an active desk, and walk-up displays that allow the system to track documents and activities in the workplace. We present the distributed user interface (DUI) model that allows standalone applications to distribute their user interface components to several devices dynamically at run-time. This mechanism permit clinicians to develop their own user interfaces and forms to clinical information systems to match their specific needs. We discuss the underlying technical concepts of DUIs and show how service discovery, component distribution, events and layout management are dealt with in the NOSTOS system. Our results suggest that DUIs--and similar network-based user interfaces--will be a prerequisite of future mobile user interfaces and essential to develop clinical multi-device environments.
Usage analysis of user files in UNIX
NASA Technical Reports Server (NTRS)
Devarakonda, Murthy V.; Iyer, Ravishankar K.
1987-01-01
Presented is a user-oriented analysis of short term file usage in a 4.2 BSD UNIX environment. The key aspect of this analysis is a characterization of users and files, which is a departure from the traditional approach of analyzing file references. Two characterization measures are employed: accesses-per-byte (combining fraction of a file referenced and number of references) and file size. This new approach is shown to distinguish differences in files as well as users, which cam be used in efficient file system design, and in creating realistic test workloads for simulations. A multi-stage gamma distribution is shown to closely model the file usage measures. Even though overall file sharing is small, some files belonging to a bulletin board system are accessed by many users, simultaneously and otherwise. Over 50% of users referenced files owned by other users, and over 80% of all files were involved in such references. Based on the differences in files and users, suggestions to improve the system performance were also made.
Knowledge Engineering Aspects of Affective Bi-Modal Educational Applications
NASA Astrophysics Data System (ADS)
Alepis, Efthymios; Virvou, Maria; Kabassi, Katerina
This paper analyses the knowledge and software engineering aspects of educational applications that provide affective bi-modal human-computer interaction. For this purpose, a system that provides affective interaction based on evidence from two different modes has been developed. More specifically, the system's inferences about students' emotions are based on user input evidence from the keyboard and the microphone. Evidence from these two modes is combined by a user modelling component that incorporates user stereotypes as well as a multi criteria decision making theory. The mechanism that integrates the inferences from the two modes has been based on the results of two empirical studies that were conducted in the context of knowledge engineering of the system. The evaluation of the developed system showed significant improvements in the recognition of the emotional states of users.
A Multi-Language System for Knowledge Extraction in E-Learning Videos
ERIC Educational Resources Information Center
Sood, Aparesh; Mittal, Ankush; Sarthi, Divya
2006-01-01
The existing multimedia software in E-Learning does not provide par excellence multimedia data service to the common user, hence E-Learning services are still short of intelligence and sophisticated end user tools for visualization and retrieval. An efficient approach to achieve the tasks such as, regional language narration, regional language…
Multi-processing control system for the SEL 840MP (MPCS/1) users guide. Volume 2: Operations guide
NASA Technical Reports Server (NTRS)
1972-01-01
The generation and operational use of the SEL 840MP multiprocessing control system (MPCS) are considered. System initialization, job task table generation, the MPCS command language, display library generation, and system error summary are reviewed.
NASA Astrophysics Data System (ADS)
Lv, Gangming; Zhu, Shihua; Hui, Hui
Multi-cell resource allocation under minimum rate request for each user in OFDMA networks is addressed in this paper. Based on Lagrange dual decomposition theory, the joint multi-cell resource allocation problem is decomposed and modeled as a limited-cooperative game, and a distributed multi-cell resource allocation algorithm is thus proposed. Analysis and simulation results show that, compared with non-cooperative iterative water-filling algorithm, the proposed algorithm can remarkably reduce the ICI level and improve overall system performances.
A DICOM based radiotherapy plan database for research collaboration and reporting
NASA Astrophysics Data System (ADS)
Westberg, J.; Krogh, S.; Brink, C.; Vogelius, I. R.
2014-03-01
Purpose: To create a central radiotherapy (RT) plan database for dose analysis and reporting, capable of calculating and presenting statistics on user defined patient groups. The goal is to facilitate multi-center research studies with easy and secure access to RT plans and statistics on protocol compliance. Methods: RT institutions are able to send data to the central database using DICOM communications on a secure computer network. The central system is composed of a number of DICOM servers, an SQL database and in-house developed software services to process the incoming data. A web site within the secure network allows the user to manage their submitted data. Results: The RT plan database has been developed in Microsoft .NET and users are able to send DICOM data between RT centers in Denmark. Dose-volume histogram (DVH) calculations performed by the system are comparable to those of conventional RT software. A permission system was implemented to ensure access control and easy, yet secure, data sharing across centers. The reports contain DVH statistics for structures in user defined patient groups. The system currently contains over 2200 patients in 14 collaborations. Conclusions: A central RT plan repository for use in multi-center trials and quality assurance was created. The system provides an attractive alternative to dummy runs by enabling continuous monitoring of protocol conformity and plan metrics in a trial.
Single-user MIMO versus multi-user MIMO in distributed antenna systems with limited feedback
NASA Astrophysics Data System (ADS)
Schwarz, Stefan; Heath, Robert W.; Rupp, Markus
2013-12-01
This article investigates the performance of cellular networks employing distributed antennas in addition to the central antennas of the base station. Distributed antennas are likely to be implemented using remote radio units, which is enabled by a low latency and high bandwidth dedicated link to the base station. This facilitates coherent transmission from potentially all available antennas at the same time. Such distributed antenna system (DAS) is an effective way to deal with path loss and large-scale fading in cellular systems. DAS can apply precoding across multiple transmission points to implement single-user MIMO (SU-MIMO) and multi-user MIMO (MU-MIMO) transmission. The throughput performance of various SU-MIMO and MU-MIMO transmission strategies is investigated in this article, employing a Long-Term evolution (LTE) standard compliant simulation framework. The previously theoretically established cell-capacity improvement of MU-MIMO in comparison to SU-MIMO in DASs is confirmed under the practical constraints imposed by the LTE standard, even under the assumption of imperfect channel state information (CSI) at the base station. Because practical systems will use quantized feedback, the performance of different CSI feedback algorithms for DASs is investigated. It is shown that significant gains in the CSI quantization accuracy and in the throughput of especially MU-MIMO systems can be achieved with relatively simple quantization codebook constructions that exploit the available temporal correlation and channel gain differences.
Reliability and throughput issues for optical wireless and RF wireless systems
NASA Astrophysics Data System (ADS)
Yu, Meng
The fast development of wireless communication technologies has two main trends. On one hand, in point-to-point communications, the demand for higher throughput called for the emergence of wireless broadband techniques including optical wireless (OW). One the other hand, wireless networks are becoming pervasive. New application of wireless networks ask for more flexible system infrastructures beyond the point-to-point prototype to achieve better performance. This dissertation investigates two topics on the reliability and throughput issues of new wireless technologies. The first topic is to study the capacity, and practical forward error control strategies for OW systems. We investigate the performance of OW systems under weak atmospheric turbulence. We first investigate the capacity and power allocation for multi-laser and multi-detector systems. Our results show that uniform power allocation is a practically optimal solution for paralleled channels. We also investigate the performance of Reed Solomon (RS) codes and turbo codes for OW systems. We present RS codes as good candidates for OW systems. The second topic targets user cooperation in wireless networks. We evaluate the relative merits of amplify-forward (AF) and decode-forward (DF) in practical scenarios. Both analysis and simulations show that the overall system performance is critically affected by the quality of the inter-user channel. Following this result, we investigate two schemes to improve the overall system performance. We first investigate the impact of the relay location on the overall system performance and determine the optimal location of relay. A best-selective single-relay 1 system is proposed and evaluated. Through the analysis of the average capacity and outage, we show that a small candidate pool of 3 to 5 relays suffices to reap most of the "geometric" gain available to a selective system. Second, we propose a new user cooperation scheme to provide an effective better inter-user channel. Most user cooperation protocols work in a time sharing manner, where a node forwards others' messages and sends its own message at different sections within a provisioned time slot. In the proposed scheme the two messages are encoded together in a single codework using network coding and transmitted in the given time slot. We also propose a general multiple-user cooperation framework. Under this framework, we show that network coding can achieve better diversity and provide effective better inter-user channels than time sharing. The last part of the dissertation focuses on multi-relay packet transmission. We propose an adaptive and distributive coding scheme for the relay nodes to adaptively cooperate and forward messages. The adaptive scheme shows performance gain over fixed schemes. Then we shift our viewpoint and represent the network as part of encoders and part of decoders.
Moon, Jongho; Choi, Younsung; Jung, Jaewook; Won, Dongho
2015-01-01
In multi-server environments, user authentication is a very important issue because it provides the authorization that enables users to access their data and services; furthermore, remote user authentication schemes for multi-server environments have solved the problem that has arisen from user's management of different identities and passwords. For this reason, numerous user authentication schemes that are designed for multi-server environments have been proposed over recent years. In 2015, Lu et al. improved upon Mishra et al.'s scheme, claiming that their remote user authentication scheme is more secure and practical; however, we found that Lu et al.'s scheme is still insecure and incorrect. In this paper, we demonstrate that Lu et al.'s scheme is vulnerable to outsider attack and user impersonation attack, and we propose a new biometrics-based scheme for authentication and key agreement that can be used in multi-server environments; then, we show that our proposed scheme is more secure and supports the required security properties.
Gonzalez-Vargas, Jose; Dosen, Strahinja; Amsuess, Sebastian; Yu, Wenwei; Farina, Dario
2015-01-01
Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI) cannot easily accommodate the system's complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns) and/or the user has a considerable impairment (limited number of available signal sources). In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate), decoding (one signal to recognize), and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair), or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces) in order to improve the usability of existing low-bandwidth HMIs.
Enabling multi-level relevance feedback on PubMed by integrating rank learning into DBMS.
Yu, Hwanjo; Kim, Taehoon; Oh, Jinoh; Ko, Ilhwan; Kim, Sungchul; Han, Wook-Shin
2010-04-16
Finding relevant articles from PubMed is challenging because it is hard to express the user's specific intention in the given query interface, and a keyword query typically retrieves a large number of results. Researchers have applied machine learning techniques to find relevant articles by ranking the articles according to the learned relevance function. However, the process of learning and ranking is usually done offline without integrated with the keyword queries, and the users have to provide a large amount of training documents to get a reasonable learning accuracy. This paper proposes a novel multi-level relevance feedback system for PubMed, called RefMed, which supports both ad-hoc keyword queries and a multi-level relevance feedback in real time on PubMed. RefMed supports a multi-level relevance feedback by using the RankSVM as the learning method, and thus it achieves higher accuracy with less feedback. RefMed "tightly" integrates the RankSVM into RDBMS to support both keyword queries and the multi-level relevance feedback in real time; the tight coupling of the RankSVM and DBMS substantially improves the processing time. An efficient parameter selection method for the RankSVM is also proposed, which tunes the RankSVM parameter without performing validation. Thereby, RefMed achieves a high learning accuracy in real time without performing a validation process. RefMed is accessible at http://dm.postech.ac.kr/refmed. RefMed is the first multi-level relevance feedback system for PubMed, which achieves a high accuracy with less feedback. It effectively learns an accurate relevance function from the user's feedback and efficiently processes the function to return relevant articles in real time.
AQBE — QBE Style Queries for Archetyped Data
NASA Astrophysics Data System (ADS)
Sachdeva, Shelly; Yaginuma, Daigo; Chu, Wanming; Bhalla, Subhash
Large-scale adoption of electronic healthcare applications requires semantic interoperability. The new proposals propose an advanced (multi-level) DBMS architecture for repository services for health records of patients. These also require query interfaces at multiple levels and at the level of semi-skilled users. In this regard, a high-level user interface for querying the new form of standardized Electronic Health Records system has been examined in this study. It proposes a step-by-step graphical query interface to allow semi-skilled users to write queries. Its aim is to decrease user effort and communication ambiguities, and increase user friendliness.
Martens-Lobenhoffer, Jens; Bode-Böger, Stefanie M; Clement, Bernd
2016-01-15
The L-arginine metabolites methylated at the guanidino moiety, such as N(G)-monomethyl-L-arginine (LNMMA), asymmetric N(G),N(G)-dimethyl-L-arginine (ADMA), and symmetric N(G),N(G')-dimethyl-L-arginine (SDMA), are long known to be present in human plasma. Far less is known about the structural isomer of LNMMA, N(δ)-monomethyl-L-arginine (δ-MMA). In prior work, it has been detected in yeast proteins, but it has not been investigated in mammalian plasma or cells. In this work, we present a method for the simultaneous and unambiguous quantification of LNMMA and δ-MMA in human plasma that is capable of detecting δ-MMA separately from LNMMA. The method comprises a simple protein precipitation sample preparation, hydrophilic interaction liquid chromatography (HILIC) gradient elution on an unmodified silica column, and triple stage mass spectrometric detection. Stable isotope-labeled D6-SDMA was used as internal standard. The calibration ranges were 25-1000 nmol/L for LNMMA and 5-350 nmol/L for δ-MMA. The intra- and inter-batch precision determinations resulted in relative standard deviations of less than 12% for both compounds with accuracies of less than 6% deviation from the expected values. In a pilot study enrolling 10 healthy volunteers, mean concentrations of 48.0 ± 7.4 nmol/L for LNMMA and 27.4 ± 7.7 nmol/L for δ-MMA were found. Copyright © 2015 Elsevier Inc. All rights reserved.
Hirota, Keiko; Shigekawa, Chihiro; Araoi, Sho; Sha, Liang; Inagawa, Takayuki; Kanou, Akihiko; Kako, Koichiro; Daitoku, Hiroaki; Fukamizu, Akiyoshi
2017-06-01
Protein arginine methyltransferases (PRMTs) catalyze the transfer of a methyl group from S-adenosylmethionine to arginine residues and are classified into two types: type I producing asymmetric dimethylarginine (ADMA) and type II producing symmetric dimethylarginine (SDMA). PRMTs have been shown to regulate many cellular processes, including signal transduction, transcriptional regulation and RNA processing. Since the loss-of-function mutation of PRMT1 and PRMT5, each of which is the predominant type I and II, respectively, causes embryonic lethality in mice, their physiological significance at the whole-body level remains largely unknown. Here, we show the morphological and functional phenotypes of single or double null alleles of prmt-1 and prmt-5 in Caenorhabditis elegans. The prmt-1;prmt-5 double mutants are viable, and exhibit short body length and small brood size compared to N2 and each of the single mutants. The liquid chromatography-tandem mass spectrometry analysis demonstrated that the levels of ADMA and SDMA were abolished in the prmt-1;prmt-5 double mutants. Both prmt-1 and prmt-5 were required for resistance to heat and oxidative stresses, whereas prmt-5 is not involved in lifespan regulation even when prmt-1 is ablated. This mutant strain would be a useful model animal for investigating the role of asymmetric and symmetric arginine dimethylation in vivo. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
Stojanovic, Ivana; Vojinovic, Slobodan; Ljubisavljevic, Srdjan; Pavlovic, Radmila; Basic, Jelena; Pavlovic, Dusica; Ilic, Andjelka; Cvetkovic, Tatjana; Stukalov, Maja
2012-12-15
The scope of this study is the examination of NO(2)+NO(3), 3-nitrotyrosine (3-NT), S-nitrosothiols (RSNO), arginase activity and asymmetric (ADMA) and symmetric (SDMA) dimethyl-L-arginine concentrations in plasma of MS patients during interferon-β1b therapy. The study population included 15 (12 women, 3 men) untreated MS patients and 12 (10 women, 2 men) interferon-β1b treated MS patients with clinically definite relapsing MS (McDonalds criteria) for at least 1 year and a baseline EDSS score of 1.0 to 3.5 inclusive. Patients were treated with 250 μg IU interferon-β1b s.c. every second day during 30 months. The disease course was evaluated using correlations between baseline EDSS score and relapse rates in both groups. During interferon-β1b treatment, EDSS scores in treated patients were decreased compared to untreated ones - after 18 and 30 months (p<0.05). In interferon-β1b treated MS patients, NO(2)+NO(3), 3-NT and RSNO plasma concentrations were significantly lower (p<0.05), while arginase activity, ADMA and SDMA levels were significantly increased (p<0.05) during the therapy, compared to the baseline levels in treated patients. The investigated parameters may be the new biomarkers, providing information for the therapeutic approach and valuable in clinical monitoring. Copyright © 2012 Elsevier B.V. All rights reserved.
Yue, Yufei; CHu, Yuzhuo; Guo, Hong
2015-01-01
Protein arginine methyltransferases (PRMTs) catalyze the transfer of the methyl group from S-adenosyl-l-methionine (AdoMet) to arginine residues. There are three types of PRMTs (I, II and III) that produce different methylation products, including asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and monomethylarginine (MMA). Since these different methylations can lead to different biological consequences, understanding the origin of product specificity of PRMTs is of considerable interest. In this article, the quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) and free energy simulations are performed to study SDMA catalyzed by the Type II PRMT5 on the basis of experimental observation that the dimethylated productmore » is generated through a distributive fashion. The simulations have identified some important interactions and proton transfers during the catalysis. Similar to the cases involving Type I PRMTs, a conserved Glu residue (Glu435) in PRMT5 is suggested to function as general base catalyst based on the result of the simulations. Moreover, our results show that PRMT5 has an energetic preference for the first methylation on N-1 followed by the second methylation on a different -guanidino nitrogen of arginine (N-2).The first and second methyl transfers are estimated to have free energy barriers of 19-20 and 18-19 kcal/mol respectively. The computer simulations suggest a distinctive catalytic mechanism of symmetric dimethylation that seems to be different from asymmetric dimethylation.« less
Metabolomic Profiling in Individuals with a Failing Kidney Allograft.
Bassi, Roberto; Niewczas, Monika A; Biancone, Luigi; Bussolino, Stefania; Merugumala, Sai; Tezza, Sara; D'Addio, Francesca; Ben Nasr, Moufida; Valderrama-Vasquez, Alessandro; Usuelli, Vera; De Zan, Valentina; El Essawy, Basset; Venturini, Massimo; Secchi, Antonio; De Cobelli, Francesco; Lin, Alexander; Chandraker, Anil; Fiorina, Paolo
2017-01-01
Alteration of certain metabolites may play a role in the pathophysiology of renal allograft disease. To explore metabolomic abnormalities in individuals with a failing kidney allograft, we analyzed by liquid chromatography-mass spectrometry (LC-MS/MS; for ex vivo profiling of serum and urine) and two dimensional correlated spectroscopy (2D COSY; for in vivo study of the kidney graft) 40 subjects with varying degrees of chronic allograft dysfunction stratified by tertiles of glomerular filtration rate (GFR; T1, T2, T3). Ten healthy non-allograft individuals were chosen as controls. LC-MS/MS analysis revealed a dose-response association between GFR and serum concentration of tryptophan, glutamine, dimethylarginine isomers (asymmetric [A]DMA and symmetric [S]DMA) and short-chain acylcarnitines (C4 and C12), (test for trend: T1-T3 = p<0.05; p = 0.01; p<0.001; p = 0.01; p = 0.01; p<0.05, respectively). The same association was found between GFR and urinary levels of histidine, DOPA, dopamine, carnosine, SDMA and ADMA (test for trend: T1-T3 = p<0.05; p<0.01; p = 0.001; p<0.05; p = 0.001; p<0.001; p<0.01, respectively). In vivo 2D COSY of the kidney allograft revealed significant reduction in the parenchymal content of choline, creatine, taurine and threonine (all: p<0.05) in individuals with lower GFR levels. We report an association between renal function and altered metabolomic profile in renal transplant individuals with different degrees of kidney graft function.
Multi-focus and multi-level techniques for visualization and analysis of networks with thematic data
NASA Astrophysics Data System (ADS)
Cossalter, Michele; Mengshoel, Ole J.; Selker, Ted
2013-01-01
Information-rich data sets bring several challenges in the areas of visualization and analysis, even when associated with node-link network visualizations. This paper presents an integration of multi-focus and multi-level techniques that enable interactive, multi-step comparisons in node-link networks. We describe NetEx, a visualization tool that enables users to simultaneously explore different parts of a network and its thematic data, such as time series or conditional probability tables. NetEx, implemented as a Cytoscape plug-in, has been applied to the analysis of electrical power networks, Bayesian networks, and the Enron e-mail repository. In this paper we briefly discuss visualization and analysis of the Enron social network, but focus on data from an electrical power network. Specifically, we demonstrate how NetEx supports the analytical task of electrical power system fault diagnosis. Results from a user study with 25 subjects suggest that NetEx enables more accurate isolation of complex faults compared to an especially designed software tool.
ERIC Educational Resources Information Center
deNoyelles, Aimee; Seo, Kay Kyeong-Ju
2012-01-01
A 3D multi-user virtual environment holds promise to support and enhance student online learning communities due to its ability to promote global synchronous interaction and collaboration, rich multisensory experience and expression, and elaborate design capabilities. Second Life[R], a multi-user virtual environment intended for adult users 18 and…
Multi-intelligence critical rating assessment of fusion techniques (MiCRAFT)
NASA Astrophysics Data System (ADS)
Blasch, Erik
2015-06-01
Assessment of multi-intelligence fusion techniques includes credibility of algorithm performance, quality of results against mission needs, and usability in a work-domain context. Situation awareness (SAW) brings together low-level information fusion (tracking and identification), high-level information fusion (threat and scenario-based assessment), and information fusion level 5 user refinement (physical, cognitive, and information tasks). To measure SAW, we discuss the SAGAT (Situational Awareness Global Assessment Technique) technique for a multi-intelligence fusion (MIF) system assessment that focuses on the advantages of MIF against single intelligence sources. Building on the NASA TLX (Task Load Index), SAGAT probes, SART (Situational Awareness Rating Technique) questionnaires, and CDM (Critical Decision Method) decision points; we highlight these tools for use in a Multi-Intelligence Critical Rating Assessment of Fusion Techniques (MiCRAFT). The focus is to measure user refinement of a situation over the information fusion quality of service (QoS) metrics: timeliness, accuracy, confidence, workload (cost), and attention (throughput). A key component of any user analysis includes correlation, association, and summarization of data; so we also seek measures of product quality and QuEST of information. Building a notion of product quality from multi-intelligence tools is typically subjective which needs to be aligned with objective machine metrics.
Lin, Kwan-Hwa; Chen, Chin-Hsing; Chen, You-Yin; Huang, Wen-Tzeng; Lai, Jin-Shin; Yu, Shang-Ming; Chang, Yuan-Jen
2014-01-01
Background The application of internet technology for telerehabilitation in patients with stroke has developed rapidly. Objective The current study aimed to evaluate the effect of a bidirectional and multi-user telerehabilitation system on balance and satisfaction in patients with chronic stroke living in long-term care facilities (LTCFs). Method This pilot study used a multi-site, blocked randomization design. Twenty-four participants from three LTCFs were recruited, and the participants were randomly assigned into the telerehabilitation (Tele) and conventional therapy (Conv) groups within each LTCF. Tele group received telerehabilitation but the Conv group received conventional therapy with two persons in each group for three sessions per week and for four weeks. The outcome measures included Berg Balance Scale (BBS), Barthel Index (BI), and the telerehabilitation satisfaction of the participants. Setting A telerehabilitation system included “therapist end” in a laboratory, and the “client end” in LTCFs. The conventional therapy was conducted in LTCFs. Results Training programs conducted for both the Tele and Conv groups showed significant effects within groups on the participant BBS as well as the total and self-care scores of BI. No significant difference between groups could be demonstrated. The satisfaction of participants between the Tele and the Conv groups also did not show significant difference. Conclusions This pilot study indicated that the multi-user telerehabilitation program is feasible for improving the balance and functional activity similar to conventional therapy in patients with chronic stroke living in LTCFs. PMID:25019632
Repetition and Diversification in Multi-Session Task Oriented Search
ERIC Educational Resources Information Center
Tyler, Sarah K.
2013-01-01
As the number of documents and the availability of information online grows, so to can the difficulty in sifting through documents to find what we're searching for. Traditional Information Retrieval (IR) systems consider the query as the representation of the user's needs, and as such are limited to the user's ability to describe the information…
Information Systems for Subject Specialists: A Multi-Modal Approach to Indexing and Classification.
ERIC Educational Resources Information Center
Swift, D.F.; And Others
A fundamental problem in the two broad approaches to indexing in the social sciences--providing structure using preferred terms, cross references, and groupings of sets of materials, or compiling a concordance of an author's terms based on occurrence, leaving users free to impose their own structure--is that different indexers and users focus on…
Multi-microphone adaptive array augmented with visual cueing.
Gibson, Paul L; Hedin, Dan S; Davies-Venn, Evelyn E; Nelson, Peggy; Kramer, Kevin
2012-01-01
We present the development of an audiovisual array that enables hearing aid users to converse with multiple speakers in reverberant environments with significant speech babble noise where their hearing aids do not function well. The system concept consists of a smartphone, a smartphone accessory, and a smartphone software application. The smartphone accessory concept is a multi-microphone audiovisual array in a form factor that allows attachment to the back of the smartphone. The accessory will also contain a lower power radio by which it can transmit audio signals to compatible hearing aids. The smartphone software application concept will use the smartphone's built in camera to acquire images and perform real-time face detection using the built-in face detection support of the smartphone. The audiovisual beamforming algorithm uses the location of talking targets to improve the signal to noise ratio and consequently improve the user's speech intelligibility. Since the proposed array system leverages a handheld consumer electronic device, it will be portable and low cost. A PC based experimental system was developed to demonstrate the feasibility of an audiovisual multi-microphone array and these results are presented.
NASA Astrophysics Data System (ADS)
Umezu, Yasuyoshi; Watanabe, Yuko; Ma, Ninshu
2005-08-01
Since 1996, Japan Research Institute Limited (JRI) has been providing a sheet metal forming simulation system called JSTAMP-Works packaged the FEM solvers of LS-DYNA and JOH/NIKE, which might be the first multistage system at that time and has been enjoying good reputation among users in Japan. To match the recent needs, "faster, more accurate and easier", of process designers and CAE engineers, a new metal forming simulation system JSTAMP-Works/NV is developed. The JSTAMP-Works/NV packaged the automatic healing function of CAD and had much more new capabilities such as prediction of 3D trimming lines for flanging or hemming, remote control of solver execution for multi-stage forming processes and shape evaluation between FEM and CAD. On the other way, a multi-stage multi-purpose inverse FEM solver HYSTAMP is developed and will be soon put into market, which is approved to be very fast, quite accurate and robust. Lastly, authors will give some application examples of user defined ductile damage subroutine in LS-DYNA for the estimation of material failure and springback in metal forming simulation.
The KALI multi-arm robot programming and control environment
NASA Technical Reports Server (NTRS)
Backes, Paul; Hayati, Samad; Hayward, Vincent; Tso, Kam
1989-01-01
The KALI distributed robot programming and control environment is described within the context of its use in the Jet Propulsion Laboratory (JPL) telerobot project. The purpose of KALI is to provide a flexible robot programming and control environment for coordinated multi-arm robots. Flexibility, both in hardware configuration and software, is desired so that it can be easily modified to test various concepts in robot programming and control, e.g., multi-arm control, force control, sensor integration, teleoperation, and shared control. In the programming environment, user programs written in the C programming language describe trajectories for multiple coordinated manipulators with the aid of KALI function libraries. A system of multiple coordinated manipulators is considered within the programming environment as one motion system. The user plans the trajectory of one controlled Cartesian frame associated with a motion system and describes the positions of the manipulators with respect to that frame. Smooth Cartesian trajectories are achieved through a blending of successive path segments. The manipulator and load dynamics are considered during trajectory generation so that given interface force limits are not exceeded.
DWTP: a basis for networked VR on the Internet
NASA Astrophysics Data System (ADS)
Broll, Wolfgang; Schick, Daniel
1998-04-01
Shared virtual worlds are one of today's major research topics. While limited to particular application areas and high speed networks in the past, they become more and more available to a large number of users. One reason for this development was the introduction of VRML (the Virtual Reality Modeling Language), which has been established as a standard of the exchange of 3D worlds on the Internet. Although a number of prototype systems have been developed to realize shared multi-user worlds based on VRML, no suitable network protocol to support the demands of such environments has yet been established. In this paper we will introduce our approach of a network protocol for shared virtual environments: DWTP--the Distributed Worlds Transfer and communication Protocol. We will show how DWTP meets the demands of shared virtual environments on the Internet. We will further present SmallView, our prototype of a distributed multi-user VR system, to show how DWTP can be used to realize shared worlds.
2007-01-01
15 4.2.3. Users of Systems for Combating Biological Warfare ................................ 16 4.2.4...21 4.3.1. Existing Biosurveillance Systems .............................................................. 22 4.3.2. Automatic Integration...74 6.4.4. Multi-Agent System Management System (MMS).................................... 75 6.4.5. Agent Glossary
Proposal for Implementing Multi-User Database (MUD) Technology in an Academic Library.
ERIC Educational Resources Information Center
Filby, A. M. Iliana
1996-01-01
Explores the use of MOO (multi-user object oriented) virtual environments in academic libraries to enhance reference services. Highlights include the development of multi-user database (MUD) technology from gaming to non-recreational settings; programming issues; collaborative MOOs; MOOs as distinguished from other types of virtual reality; audio…
Evans, William D [Cupertino, CA
2009-02-24
A secure content object protects electronic documents from unauthorized use. The secure content object includes an encrypted electronic document, a multi-key encryption table having at least one multi-key component, an encrypted header and a user interface device. The encrypted document is encrypted using a document encryption key associated with a multi-key encryption method. The encrypted header includes an encryption marker formed by a random number followed by a derivable variation of the same random number. The user interface device enables a user to input a user authorization. The user authorization is combined with each of the multi-key components in the multi-key encryption key table and used to try to decrypt the encrypted header. If the encryption marker is successfully decrypted, the electronic document may be decrypted. Multiple electronic documents or a document and annotations may be protected by the secure content object.
Real English: A Translator to Enable Natural Language Man-Machine Conversation.
ERIC Educational Resources Information Center
Gautin, Harvey
This dissertation presents a pragmatic interpreter/translator called Real English to serve as a natural language man-machine communication interface in a multi-mode on-line information retrieval system. This multi-mode feature affords the user a library-like searching tool by giving him access to a dictionary, lexicon, thesaurus, synonym table,…
Xu, Ren; Jiang, Ning; Dosen, Strahinja; Lin, Chuang; Mrachacz-Kersting, Natalie; Dremstrup, Kim; Farina, Dario
2016-08-01
In this study, we present a novel multi-class brain-computer interface (BCI) for communication and control. In this system, the information processing is shared by the algorithm (computer) and the user (human). Specifically, an electro-tactile cycle was presented to the user, providing the choice (class) by delivering timely sensory input. The user discriminated these choices by his/her endogenous sensory ability and selected the desired choice with an intuitive motor task. This selection was detected by a fast brain switch based on real-time detection of movement-related cortical potentials from scalp EEG. We demonstrated the feasibility of such a system with a four-class BCI, yielding a true positive rate of ∼ 80% and ∼ 70%, and an information transfer rate of ∼ 7 bits/min and ∼ 5 bits/min, for the movement and imagination selection command, respectively. Furthermore, when the system was extended to eight classes, the throughput of the system was improved, demonstrating the capability of accommodating a large number of classes. Combining the endogenous sensory discrimination with the fast brain switch, the proposed system could be an effective, multi-class, gaze-independent BCI system for communication and control applications.
Gonzalez-Vargas, Jose; Dosen, Strahinja; Amsuess, Sebastian; Yu, Wenwei; Farina, Dario
2015-01-01
Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI) cannot easily accommodate the system’s complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns) and/or the user has a considerable impairment (limited number of available signal sources). In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate), decoding (one signal to recognize), and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair), or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces) in order to improve the usability of existing low-bandwidth HMIs. PMID:26069961
ERIC Educational Resources Information Center
Panettieri, Joseph C.
2007-01-01
Across the globe, progressive universities are embracing any number of MUVEs (multi-user virtual environments), 3D environments, and "immersive" virtual reality tools. And within the next few months, several universities are expected to test so-called "telepresence" videoconferencing systems from Cisco Systems and other leading…
FRIEND: a brain-monitoring agent for adaptive and assistive systems.
Morris, Alexis; Ulieru, Mihaela
2012-01-01
This paper presents an architectural design for adaptive-systems agents (FRIEND) that use brain state information to make more effective decisions on behalf of a user; measuring brain context versus situational demands. These systems could be useful for alerting users to cognitive workload levels or fatigue, and could attempt to compensate for higher cognitive activity by filtering noise information. In some cases such systems could also share control of devices, such as pulling over in an automated vehicle. These aim to assist people in everyday systems to perform tasks better and be more aware of internal states. Achieving a functioning system of this sort is a challenge, involving a unification of brain- computer-interfaces, human-computer-interaction, soft-computin deliberative multi-agent systems disciplines. Until recently, these were not able to be combined into a usable platform due largely to technological limitations (e.g., size, cost, and processing speed), insufficient research on extracting behavioral states from EEG signals, and lack of low-cost wireless sensing headsets. We aim to surpass these limitations and develop control architectures for making sense of brain state in applications by realizing an agent architecture for adaptive (human-aware) technology. In this paper we present an early, high-level design towards implementing a multi-purpose brain-monitoring agent system to improve user quality of life through the assistive applications of psycho-physiological monitoring, noise-filtering, and shared system control.
NASA Astrophysics Data System (ADS)
Lee, Sam; Lucas, Nathan P.; Ellis, R. Darin; Pandya, Abhilash
2012-06-01
This paper presents a seamlessly controlled human multi-robot system comprised of ground and aerial robots of semiautonomous nature for source localization tasks. The system combines augmented reality interfaces capabilities with human supervisor's ability to control multiple robots. The role of this human multi-robot interface is to allow an operator to control groups of heterogeneous robots in real time in a collaborative manner. It used advanced path planning algorithms to ensure obstacles are avoided and that the operators are free for higher-level tasks. Each robot knows the environment and obstacles and can automatically generate a collision-free path to any user-selected target. It displayed sensor information from each individual robot directly on the robot in the video view. In addition, a sensor data fused AR view is displayed which helped the users pin point source information or help the operator with the goals of the mission. The paper studies a preliminary Human Factors evaluation of this system in which several interface conditions are tested for source detection tasks. Results show that the novel Augmented Reality multi-robot control (Point-and-Go and Path Planning) reduced mission completion times compared to the traditional joystick control for target detection missions. Usability tests and operator workload analysis are also investigated.
REACH: Real-Time Data Awareness in Multi-Spacecraft Missions
NASA Technical Reports Server (NTRS)
Maks, Lori; Coleman, Jason; Hennessy, Joseph F. (Technical Monitor)
2002-01-01
NASA's Advanced Architectures and Automation Branch at the Goddard Space Flight Center (Code 588) saw the potential to reduce the cost of constellation missions by creating new user interfaces to the ground system health-and-safety data. The goal is to enable a small Flight Operations Team (FOT) to remain aware and responsive to the increased amount of ground system information in a multi-spacecraft environment. Rather than abandon the tried and true, these interfaces were developed to run alongside existing ground system software to provide additional support to the FOT. These new user interfaces have been combined in a tool called REACH. REACH-the Real-time Evaluation and Analysis of Consolidated Health-is a software product that uses advanced visualization techniques to make spacecraft anomalies easy to spot, no matter how many spacecraft are in the constellation. REACH reads numerous real-time streams of data from the ground system(s) and displays synthesized information to the FOT such that anomalies are easy to pick out and investigate.
Sensor-Based Human Activity Recognition in a Multi-user Scenario
NASA Astrophysics Data System (ADS)
Wang, Liang; Gu, Tao; Tao, Xianping; Lu, Jian
Existing work on sensor-based activity recognition focuses mainly on single-user activities. However, in real life, activities are often performed by multiple users involving interactions between them. In this paper, we propose Coupled Hidden Markov Models (CHMMs) to recognize multi-user activities from sensor readings in a smart home environment. We develop a multimodal sensing platform and present a theoretical framework to recognize both single-user and multi-user activities. We conduct our trace collection done in a smart home, and evaluate our framework through experimental studies. Our experimental result shows that we achieve an average accuracy of 85.46% with CHMMs.
Joint channel estimation and multi-user detection for multipath fading channels in DS-CDMA systems
NASA Astrophysics Data System (ADS)
Wu, Sau-Hsuan; Kuo, C.-C. Jay
2002-11-01
The technique of joint blind channel estimation and multiple access interference (MAI) suppression for an asynchronous code-division multiple-access (CDMA) system is investigated in this research. To identify and track dispersive time-varying fading channels and to avoid the phase ambiguity that come with the second-order statistic approaches, a sliding-window scheme using the expectation maximization (EM) algorithm is proposed. The complexity of joint channel equalization and symbol detection for all users increases exponentially with system loading and the channel memory. The situation is exacerbated if strong inter-symbol interference (ISI) exists. To reduce the complexity and the number of samples required for channel estimation, a blind multiuser detector is developed. Together with multi-stage interference cancellation using soft outputs provided by this detector, our algorithm can track fading channels with no phase ambiguity even when channel gains attenuate close to zero.
Usage of Multi-Mission Radioisotope Thermoelectric Generators (MMRTGs) for Future Potential Missions
NASA Technical Reports Server (NTRS)
Zakrajsek, June F.; Cairns-Gallimore, Dirk; Otting, Bill; Johnson, Steve; Woerner, Dave
2016-01-01
The goal of NASAs Radioisotope Power Systems (RPS) Program is to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet the needs of the missions. To meet this goal, the RPS Program, working closely with the Department of Energy, performs mission and system studies (such as the recently released Nuclear Power Assessment Study), evaluates the readiness of promising technologies to infuse in future generators, assesses the sustainment of key RPS capabilities and knowledge, forecasts and tracks the Programs budgetary needs, and disseminates current information about RPS to the community of potential users. This presentation focuses on the needs of the mission community and provides users a better understanding of how to integrate the MMRTG (Multi-Mission Radioisotope Thermoelectric Generator).
Interconnecting Multidiscilinary Data Infrastructures: From Federation to Brokering Framework
NASA Astrophysics Data System (ADS)
Nativi, S.
2014-12-01
Standardization and federation activities have been played an essential role to push interoperability at the disciplinary and cross-disciplinary level. However, they demonstrated not to be sufficient to resolve important interoperability challenges, including: disciplinary heterogeneity, cross-organizations diversities, cultural differences. Significant international initiatives like GEOSS, IODE, and CEOS demonstrated that a federation system dealing with global and multi-disciplinary domain turns out to be rater complex, raising more the already high entry level barriers for both Providers and Users. In particular, GEOSS demonstrated that standardization and federation actions must be accompanied and complemented by a brokering approach. Brokering architecture and its implementing technologies are able to implement an effective interoperability level among multi-disciplinary systems, lowering the entry level barriers for both data providers and users. This presentation will discuss the brokering philosophy as a complementary approach for standardization and federation to interconnect existing and heterogeneous infrastructures and systems. The GEOSS experience will be analyzed, specially.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Van Passel, Steven, E-mail: Steven.vanpassel@uhasselt.be; University of Antwerp, Department Bioscience Engineering, Groenenborgerlaan 171, 2020 Antwerp; Meul, Marijke
Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA)more » and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. - Highlights: Black-Right-Pointing-Pointer We give an overview of sustainability assessment tools for agricultural systems. Black-Right-Pointing-Pointer SVA and MOTIFS are used to evaluate the sustainability of dairy farming in Flanders. Black-Right-Pointing-Pointer Combination of methods with different levels broadens the insights of different end-user groups. Black-Right-Pointing-Pointer We propose guidelines for multilevel and multi-user sustainability assessments.« less
NASA Technical Reports Server (NTRS)
Anderson, W. F.; Conway, J. R.; Keller, L. C.
1972-01-01
The characteristics of the application program were developed to verify and demonstrate the SEL 840MP Multi-Processing Control System - Version I (MPCS/1). The application program emphasizes the display support and task control capabilities. The application program is further intended to be used as an aid to familization with MPCS/1. It complements the information provided in the MPCS/1 Users Guide, Volume I and II.
Design Concerns in the Engineering of Virtual Worlds for Learning
ERIC Educational Resources Information Center
Rapanotti, Lucia; Hall, Jon G.
2011-01-01
The convergence of 3D simulation and social networking into current multi-user virtual environments has opened the door to new forms of interaction for learning in order to complement the face-to-face and Web 2.0-based systems. Yet, despite a growing user community, design knowledge for virtual worlds remains patchy, particularly when it comes to…
ERIC Educational Resources Information Center
Jenkins, Darrell L.
The development, testing, introduction, evaluation, and refinement of a user interface for a statewide, multi-library online public access catalog network can be a very involved and politically complex enterprise. A multitude of perspectives, assumptions, preferences, and needs accompanies the multitude of players involved, i.e., library…
Questionnaires for eliciting evaluation data from users of interactive question answering
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelly, Diane; Kantor, Paul B.; Morse, Emile
Evaluating interactive question answering (QA) systems with real users can be challenging because traditional evaluation measures based on the relevance of items returned are difficult to employ since relevance judgments can be unstable in multi-user evaluations. The work reported in this paper evaluates, in distinguishing among a set of interactive QA systems, the effectiveness of three questionnaires: a Cognitive Workload Questionnaire (NASA TLX), and Task and System Questionnaires customized to a specific interactive QA application. These Questionnaires were evaluated with four systems, seven analysts, and eight scenarios during a 2-week workshop. Overall, results demonstrate that all three Questionnaires are effectivemore » at distinguishing among systems, with the Task Questionnaire being the most sensitive. Results also provide initial support for the validity and reliability of the Questionnaires.« less
The Application of Security Concepts to the Personnel Database for the Indonesian Navy.
1983-09-01
Postgraduate School, lionterey, California, June 1982. Since 1977, the Indonesian Navy Data Center (DISPULAHTAL) has collected and processed pa-sonnel data to...zel dlta Processing in the Indonesian Navy. 4 -a "o ’% ’." 5. ’S 1 1’S~. . . II. THE _IIIT_ IPR2ES1D PERSONSEL DATABASE SYSTEM The present Database...LEVEL *USER PROCESSING :CONCURRENT MULTI USER/LEVEL Ulf, U 3 , U 3 . . . users S. .. ...... secret C. .. ...... classified U .. .. ..... unclassified
A Distributed Multi-Agent System for Collaborative Information Management and Learning
NASA Technical Reports Server (NTRS)
Chen, James R.; Wolfe, Shawn R.; Wragg, Stephen D.; Koga, Dennis (Technical Monitor)
2000-01-01
In this paper, we present DIAMS, a system of distributed, collaborative agents to help users access, manage, share and exchange information. A DIAMS personal agent helps its owner find information most relevant to current needs. It provides tools and utilities for users to manage their information repositories with dynamic organization and virtual views. Flexible hierarchical display is integrated with indexed query search-to support effective information access. Automatic indexing methods are employed to support user queries and communication between agents. Contents of a repository are kept in object-oriented storage to facilitate information sharing. Collaboration between users is aided by easy sharing utilities as well as automated information exchange. Matchmaker agents are designed to establish connections between users with similar interests and expertise. DIAMS agents provide needed services for users to share and learn information from one another on the World Wide Web.
Computer Security Products Technology Overview
1988-10-01
13 3. DATABASE MANAGEMENT SYSTEMS ................................... 15 Definition...this paper addresses fall into the areas of multi-user hosts, database management systems (DBMS), workstations, networks, guards and gateways, and...provide a portion of that protection, for example, a password scheme, a file protection mechanism, a secure database management system, or even a
T-LECS: The Control Software System for MOIRCS
NASA Astrophysics Data System (ADS)
Yoshikawa, T.; Omata, K.; Konishi, M.; Ichikawa, T.; Suzuki, R.; Tokoku, C.; Katsuno, Y.; Nishimura, T.
2006-07-01
MOIRCS (Multi-Object Infrared Camera and Spectrograph) is a new instrument for the Subaru Telescope. We present the system design of the control software system for MOIRCS, named T-LECS (Tohoku University - Layered Electronic Control System). T-LECS is a PC-Linux based network distributed system. Two PCs equipped with the focal plane array system operate two HAWAII2 detectors, respectively, and another PC is used for user interfaces and a database server. Moreover, these PCs control various devices for observations distributed on a TCP/IP network. T-LECS has three interfaces; interfaces to the devices and two user interfaces. One of the user interfaces is to the integrated observation control system (Subaru Observation Software System) for observers, and another one provides the system developers the direct access to the devices of MOIRCS. In order to help the communication between these interfaces, we employ an SQL database system.
Big data privacy protection model based on multi-level trusted system
NASA Astrophysics Data System (ADS)
Zhang, Nan; Liu, Zehua; Han, Hongfeng
2018-05-01
This paper introduces and inherit the multi-level trusted system model that solves the Trojan virus by encrypting the privacy of user data, and achieve the principle: "not to read the high priority hierarchy, not to write the hierarchy with low priority". Thus ensuring that the low-priority data privacy leak does not affect the disclosure of high-priority data privacy. This paper inherits the multi-level trustworthy system model of Trojan horse and divides seven different risk levels. The priority level 1˜7 represent the low to high value of user data privacy, and realize seven kinds of encryption with different execution efficiency Algorithm, the higher the priority, the greater the value of user data privacy, at the expense of efficiency under the premise of choosing a more encrypted encryption algorithm to ensure data security. For enterprises, the price point is determined by the unit equipment users to decide the length of time. The higher the risk sub-group algorithm, the longer the encryption time. The model assumes that users prefer the lower priority encryption algorithm to ensure efficiency. This paper proposes a privacy cost model for each of the seven risk subgroups. Among them, the higher the privacy cost, the higher the priority of the risk sub-group, the higher the price the user needs to pay to ensure the privacy of the data. Furthermore, by introducing the existing pricing model of economics and the human traffic model proposed by this paper and fluctuating with the market demand, this paper improves the price of unit products when the market demand is low. On the other hand, when the market demand increases, the profit of the enterprise will be guaranteed under the guidance of the government by reducing the price per unit of product. Then, this paper introduces the dynamic factors of consumers' mood and age to optimize. At the same time, seven algorithms are selected from symmetric and asymmetric encryption algorithms to define the enterprise costs at different levels. Therefore, the proposed model solves the continuous influence caused by cascading events and ensures that the disclosure of low-level data privacy of users does not affect the high-level data privacy, thus greatly improving the safety of the private information of user.
Usability testing of a prototype multi-user telehealth kiosk.
Courtney, Karen L; Matthews, Judith T; McMillan, Julie M; Person Mecca, Laurel; Smailagic, Asim; Siewiorek, Daniel
2015-01-01
The overall purpose of this study was to learn how community-dwelling older adults would interact with our prototype multi-user telehealth kiosk and their views about its usability. Seven subjects participated in laboratory-based usability sessions to evaluate the physical design, appearance, functionality and perceived ease of use of a multi-user telehealth kiosk prototype. During usability testing participants recommended 18 new features (29% of comments), identified 15 software errors (23% of comments) and 29 user interface errors (47% of comments).
Recreational System Optimization to Reduce Conflict on Public Lands
NASA Astrophysics Data System (ADS)
Shilling, Fraser; Boggs, Jennifer; Reed, Sarah
2012-09-01
In response to federal administrative rule, the Tahoe National Forest (TNF), California, USA engaged in trail-route prioritization for motorized recreation (e.g., off-highway-vehicles) and other recreation types. The prioritization was intended to identify routes that were suitable and ill-suited for maintenance in a transportation system. A recreational user survey was conducted online ( n = 813) for user preferences for trail system characteristics, recreational use patterns, and demographics. Motorized trail users and non-motorized users displayed very clear and contrasting preferences for the same system. As has been found by previous investigators, non-motorized users expressed antagonism to motorized use on the same recreational travel system, whereas motorized users either supported multiple-use routes or dismissed non-motorized recreationists' concerns. To help the TNF plan for reduced conflict, a geographic information system (GIS) based modeling approach was used to identify recreational opportunities and potential environmental impacts of all travel routes. This GIS-based approach was based on an expert-derived rule set. The rules addressed particular environmental and recreation concerns in the TNF. Route segments were identified that could be incorporated into minimal-impact networks to support various types of recreation. The combination of potential impacts and user-benefits supported an optimization approach for an appropriate recreational travel network to minimize environmental impacts and user-conflicts in a multi-purpose system.
Recreational system optimization to reduce conflict on public lands.
Shilling, Fraser; Boggs, Jennifer; Reed, Sarah
2012-09-01
In response to federal administrative rule, the Tahoe National Forest (TNF), California, USA engaged in trail-route prioritization for motorized recreation (e.g., off-highway-vehicles) and other recreation types. The prioritization was intended to identify routes that were suitable and ill-suited for maintenance in a transportation system. A recreational user survey was conducted online (n = 813) for user preferences for trail system characteristics, recreational use patterns, and demographics. Motorized trail users and non-motorized users displayed very clear and contrasting preferences for the same system. As has been found by previous investigators, non-motorized users expressed antagonism to motorized use on the same recreational travel system, whereas motorized users either supported multiple-use routes or dismissed non-motorized recreationists' concerns. To help the TNF plan for reduced conflict, a geographic information system (GIS) based modeling approach was used to identify recreational opportunities and potential environmental impacts of all travel routes. This GIS-based approach was based on an expert-derived rule set. The rules addressed particular environmental and recreation concerns in the TNF. Route segments were identified that could be incorporated into minimal-impact networks to support various types of recreation. The combination of potential impacts and user-benefits supported an optimization approach for an appropriate recreational travel network to minimize environmental impacts and user-conflicts in a multi-purpose system.
ERIC Educational Resources Information Center
Chin, Jui-Chih; Tsuei, Mengping
2014-01-01
The aim of this study was to explore the digital game-based learning for children with chronic illnesses in the hospital settings. The design-based research and qualitative methods were applied. Three eight-year-old children with leukemia participated in this study. In the first phase, the multi-user game-based learning system was developed and…
Magnetic MIMO Signal Processing and Optimization for Wireless Power Transfer
NASA Astrophysics Data System (ADS)
Yang, Gang; Moghadam, Mohammad R. Vedady; Zhang, Rui
2017-06-01
In magnetic resonant coupling (MRC) enabled multiple-input multiple-output (MIMO) wireless power transfer (WPT) systems, multiple transmitters (TXs) each with one single coil are used to enhance the efficiency of simultaneous power transfer to multiple single-coil receivers (RXs) by constructively combining their induced magnetic fields at the RXs, a technique termed "magnetic beamforming". In this paper, we study the optimal magnetic beamforming design in a multi-user MIMO MRC-WPT system. We introduce the multi-user power region that constitutes all the achievable power tuples for all RXs, subject to the given total power constraint over all TXs as well as their individual peak voltage and current constraints. We characterize each boundary point of the power region by maximizing the sum-power deliverable to all RXs subject to their minimum harvested power constraints. For the special case without the TX peak voltage and current constraints, we derive the optimal TX current allocation for the single-RX setup in closed-form as well as that for the multi-RX setup. In general, the problem is a non-convex quadratically constrained quadratic programming (QCQP), which is difficult to solve. For the case of one single RX, we show that the semidefinite relaxation (SDR) of the problem is tight. For the general case with multiple RXs, based on SDR we obtain two approximate solutions by applying time-sharing and randomization, respectively. Moreover, for practical implementation of magnetic beamforming, we propose a novel signal processing method to estimate the magnetic MIMO channel due to the mutual inductances between TXs and RXs. Numerical results show that our proposed magnetic channel estimation and adaptive beamforming schemes are practically effective, and can significantly improve the power transfer efficiency and multi-user performance trade-off in MIMO MRC-WPT systems.
mlCAF: Multi-Level Cross-Domain Semantic Context Fusioning for Behavior Identification.
Razzaq, Muhammad Asif; Villalonga, Claudia; Lee, Sungyoung; Akhtar, Usman; Ali, Maqbool; Kim, Eun-Soo; Khattak, Asad Masood; Seung, Hyonwoo; Hur, Taeho; Bang, Jaehun; Kim, Dohyeong; Ali Khan, Wajahat
2017-10-24
The emerging research on automatic identification of user's contexts from the cross-domain environment in ubiquitous and pervasive computing systems has proved to be successful. Monitoring the diversified user's contexts and behaviors can help in controlling lifestyle associated to chronic diseases using context-aware applications. However, availability of cross-domain heterogeneous contexts provides a challenging opportunity for their fusion to obtain abstract information for further analysis. This work demonstrates extension of our previous work from a single domain (i.e., physical activity) to multiple domains (physical activity, nutrition and clinical) for context-awareness. We propose multi-level Context-aware Framework (mlCAF), which fuses the multi-level cross-domain contexts in order to arbitrate richer behavioral contexts. This work explicitly focuses on key challenges linked to multi-level context modeling, reasoning and fusioning based on the mlCAF open-source ontology. More specifically, it addresses the interpretation of contexts from three different domains, their fusioning conforming to richer contextual information. This paper contributes in terms of ontology evolution with additional domains, context definitions, rules and inclusion of semantic queries. For the framework evaluation, multi-level cross-domain contexts collected from 20 users were used to ascertain abstract contexts, which served as basis for behavior modeling and lifestyle identification. The experimental results indicate a context recognition average accuracy of around 92.65% for the collected cross-domain contexts.
NASA Astrophysics Data System (ADS)
Elfman, Mikael; Ros, Linus; Kristiansson, Per; Nilsson, E. J. Charlotta; Pallon, Jan
2016-03-01
With the recent advances towards modern Ion Beam Analysis (IBA), going from one- or few-parameter detector systems to multi-parameter systems, it has been necessary to expand and replace the more than twenty years old CAMAC based system. A new VME multi-parameter (presently up to 200 channels) data acquisition and control system has been developed and implemented at the Lund Ion Beam Analysis Facility (LIBAF). The system is based on the VX-511 Single Board Computer (SBC), acting as master with arbiter functionality and consists of standard VME modules like Analog to Digital Converters (ADC's), Charge to Digital Converters (QDC's), Time to Digital Converters (TDC's), scaler's, IO-cards, high voltage and waveform units. The modules have been specially selected to support all of the present detector systems in the laboratory, with the option of future expansion. Typically, the detector systems consist of silicon strip detectors, silicon drift detectors and scintillator detectors, for detection of charged particles, X-rays and γ-rays. The data flow of the raw data buffers out from the VME bus to the final storage place on a 16 terabyte network attached storage disc (NAS-disc) is described. The acquisition process, remotely controlled over one of the SBCs ethernet channels, is also discussed. The user interface is written in the Kmax software package, and is used to control the acquisition process as well as for advanced online and offline data analysis through a user-friendly graphical user interface (GUI). In this work the system implementation, layout and performance are presented. The user interface and possibilities for advanced offline analysis are also discussed and illustrated.
NASA Technical Reports Server (NTRS)
Laymon, Charles A,; Kress, Martin P.; McCracken, Jeff E.; Spehn, Stephen L.; Tanner, Steve
2011-01-01
The Arctic Collaborative Environment (ACE) project is a new international partnership for information sharing to meet the challenges of addressing Arctic. The goal of ACE is to create an open source, web-based, multi-national monitoring, analysis, and visualization decision-support system for Arctic environmental assessment, management, and sustainability. This paper will describe the concept, system architecture, and data products that are being developed and disseminated among partners and independent users through remote access.
Special Technology Area Review on Micro-Opto-Electro-Mechanical-Systems (MOEMS)
1997-12-01
Optical Interference in Night Vision Systems "* DMD Assisted Intelligent Manufacturing of ................................................... SRI...CONCEPT ......................................... p. 8 FIGURE 3(a): DMD LIGHT SWITCHES...p. 9 FIGURE 3(b): SEM PHOTOMICROGRAPHS OF DMD CHIPS ........................................ p. 9 FIGURE 4: MULTI-USER MEMS PROJECTS (MUMPS
[EXPERIENCE IN THE APPLICATION OF DATABASES ON BLOODSUCKING INSECTS IN ZOOLOGICAL STUDIES].
Medvedev, S G; Khalikov, R G
2016-01-01
The paper summarizes long-term experience of accumulating and summarizing the faunistic information by means of separate databases (DB) and information analytical systems (IAS), and also prospects of its representation by modern multi-user informational systems. The experience obtained during development and practical use of the PARHOST1 IAS for the study of the world flea fauna and work with personal databases created for the study of bloodsucking insects (lice and blackflies) is analyzed. Research collection material on type series of 57 species and subspecies of fleas of the fauna of Russia was approved as a part of multi-user information retrieval system on the web-portal of the Zoological Institute of the Russian Academy of Sciences. According former investigations, the system allows depositing the information in the authentic form and performing its gradual transformation, i. e. its unification and structuring. In order to provide continuity of DB refill, the possibility of work of operators with different degree of competence is provided.
Multi-Sector Sustainability Browser (MSSB) User Manual: A ...
EPA’s Sustainable and Healthy Communities (SHC) Research Program is developing methodologies, resources, and tools to assist community members and local decision makers in implementing policy choices that facilitate sustainable approaches in managing their resources affecting the built environment, natural environment, and human health. In order to assist communities and decision makers in implementing sustainable practices, EPA is developing computer-based systems including models, databases, web tools, and web browsers to help communities decide upon approaches that support their desired outcomes. Communities need access to resources that will allow them to achieve their sustainability objectives through intelligent decisions in four key sustainability areas: • Land Use • Buildings and Infrastructure • Transportation • Materials Management (i.e., Municipal Solid Waste [MSW] processing and disposal) The Multi-Sector Sustainability Browser (MSSB) is designed to support sustainable decision-making for communities, local and regional planners, and policy and decision makers. Document is an EPA Technical Report, which is the user manual for the Multi-Sector Sustainability Browser (MSSB) tool. The purpose of the document is to provide basic guidance on use of the tool for users
Moon, Jongho; Choi, Younsung; Jung, Jaewook; Won, Dongho
2015-01-01
In multi-server environments, user authentication is a very important issue because it provides the authorization that enables users to access their data and services; furthermore, remote user authentication schemes for multi-server environments have solved the problem that has arisen from user’s management of different identities and passwords. For this reason, numerous user authentication schemes that are designed for multi-server environments have been proposed over recent years. In 2015, Lu et al. improved upon Mishra et al.’s scheme, claiming that their remote user authentication scheme is more secure and practical; however, we found that Lu et al.’s scheme is still insecure and incorrect. In this paper, we demonstrate that Lu et al.’s scheme is vulnerable to outsider attack and user impersonation attack, and we propose a new biometrics-based scheme for authentication and key agreement that can be used in multi-server environments; then, we show that our proposed scheme is more secure and supports the required security properties. PMID:26709702
Maitra, Tanmoy; Giri, Debasis
2014-12-01
The medical organizations have introduced Telecare Medical Information System (TMIS) to provide a reliable facility by which a patient who is unable to go to a doctor in critical or urgent period, can communicate to a doctor through a medical server via internet from home. An authentication mechanism is needed in TMIS to hide the secret information of both parties, namely a server and a patient. Recent research includes patient's biometric information as well as password to design a remote user authentication scheme that enhances the security level. In a single server environment, one server is responsible for providing services to all the authorized remote patients. However, the problem arises if a patient wishes to access several branch servers, he/she needs to register to the branch servers individually. In 2014, Chuang and Chen proposed an remote user authentication scheme for multi-server environment. In this paper, we have shown that in their scheme, an non-register adversary can successfully logged-in into the system as a valid patient. To resist the weaknesses, we have proposed an authentication scheme for TMIS in multi-server environment where the patients can register to a root telecare server called registration center (RC) in one time to get services from all the telecare branch servers through their registered smart card. Security analysis and comparison shows that our proposed scheme provides better security with low computational and communication cost.
Selecting the Best Mobile Information Service with Natural Language User Input
NASA Astrophysics Data System (ADS)
Feng, Qiangze; Qi, Hongwei; Fukushima, Toshikazu
Information services accessed via mobile phones provide information directly relevant to subscribers’ daily lives and are an area of dynamic market growth worldwide. Although many information services are currently offered by mobile operators, many of the existing solutions require a unique gateway for each service, and it is inconvenient for users to have to remember a large number of such gateways. Furthermore, the Short Message Service (SMS) is very popular in China and Chinese users would prefer to access these services in natural language via SMS. This chapter describes a Natural Language Based Service Selection System (NL3S) for use with a large number of mobile information services. The system can accept user queries in natural language and navigate it to the required service. Since it is difficult for existing methods to achieve high accuracy and high coverage and anticipate which other services a user might want to query, the NL3S is developed based on a Multi-service Ontology (MO) and Multi-service Query Language (MQL). The MO and MQL provide semantic and linguistic knowledge, respectively, to facilitate service selection for a user query and to provide adaptive service recommendations. Experiments show that the NL3S can achieve 75-95% accuracies and 85-95% satisfactions for processing various styles of natural language queries. A trial involving navigation of 30 different mobile services shows that the NL3S can provide a viable commercial solution for mobile operators.
A multi-criteria approach to camera motion design for volume data animation.
Hsu, Wei-Hsien; Zhang, Yubo; Ma, Kwan-Liu
2013-12-01
We present an integrated camera motion design and path generation system for building volume data animations. Creating animations is an essential task in presenting complex scientific visualizations. Existing visualization systems use an established animation function based on keyframes selected by the user. This approach is limited in providing the optimal in-between views of the data. Alternatively, computer graphics and virtual reality camera motion planning is frequently focused on collision free movement in a virtual walkthrough. For semi-transparent, fuzzy, or blobby volume data the collision free objective becomes insufficient. Here, we provide a set of essential criteria focused on computing camera paths to establish effective animations of volume data. Our dynamic multi-criteria solver coupled with a force-directed routing algorithm enables rapid generation of camera paths. Once users review the resulting animation and evaluate the camera motion, they are able to determine how each criterion impacts path generation. In this paper, we demonstrate how incorporating this animation approach with an interactive volume visualization system reduces the effort in creating context-aware and coherent animations. This frees the user to focus on visualization tasks with the objective of gaining additional insight from the volume data.
Duncan, R G; Saperia, D; Dulbandzhyan, R; Shabot, M M; Polaschek, J X; Jones, D T
2001-01-01
The advent of the World-Wide-Web protocols and client-server technology has made it easy to build low-cost, user-friendly, platform-independent graphical user interfaces to health information systems and to integrate the presentation of data from multiple systems. The authors describe a Web interface for a clinical data repository (CDR) that was moved from concept to production status in less than six months using a rapid prototyping approach, multi-disciplinary development team, and off-the-shelf hardware and software. The system has since been expanded to provide an integrated display of clinical data from nearly 20 disparate information systems.
Asymmetric dimethylarginine, related arginine derivatives, and incident atrial fibrillation.
Schnabel, Renate B; Maas, Renke; Wang, Na; Yin, Xiaoyan; Larson, Martin G; Levy, Daniel; Ellinor, Patrick T; Lubitz, Steven A; McManus, David D; Magnani, Jared W; Atzler, Dorothee; Böger, Rainer H; Schwedhelm, Edzard; Vasan, Ramachandran S; Benjamin, Emelia J
2016-06-01
Oxidative stress plays an important role in the development of atrial fibrillation (AF). Arginine derivatives including asymmetric dimethylarginine (ADMA) are central to nitric oxide metabolism and nitrosative stress. Whether blood concentrations of arginine derivatives are related to incidence of AF is uncertain. In 3,310 individuals (mean age 58 ± 10 years, 54% women) from the community-based Framingham Study, we prospectively examined the relations of circulating levels of ADMA, l-arginine, symmetric dimethylarginine (SDMA), and the ratio of l-arginine/ADMA to incidence of AF using proportional hazards regression models. Over a median follow-up time of 10 years, 247 AF cases occurred. Using age- and sex-adjusted regression models, ADMA was associated with a hazard ratio of 1.15 per 1-SD increase in loge-biomarker concentration (95% CI 1.02-1.29, P = .02) for AF, which was no longer significant after further risk factor adjustment (hazard ratio 1.09, 95% CI 0.97-1.23, P = .15). Neither l-arginine nor SDMA was related to new-onset AF. A clinical model comprising clinical risk factors for AF (for age, sex, height, weight, systolic blood pressure, diastolic blood pressure, current smoking, diabetes, hypertension treatment, myocardial infarction, and heart failure; c statistic = 0.781; 95% CI 0.753-0.808) was not improved by the addition of ADMA (0.782; 95% CI 0.755-0.809). Asymmetric dimethylarginine and related arginine derivatives were not associated with incident AF in the community after accounting for other clinical risk factors and confounders. Its role in the pathogenesis of AF needs further refinement. Copyright © 2016 Elsevier Inc. All rights reserved.
Metabolomic Profiling in Individuals with a Failing Kidney Allograft
Biancone, Luigi; Bussolino, Stefania; Merugumala, Sai; Tezza, Sara; D’Addio, Francesca; Ben Nasr, Moufida; Valderrama-Vasquez, Alessandro; Usuelli, Vera; De Zan, Valentina; El Essawy, Basset; Venturini, Massimo; Secchi, Antonio; De Cobelli, Francesco; Lin, Alexander; Chandraker, Anil; Fiorina, Paolo
2017-01-01
Background Alteration of certain metabolites may play a role in the pathophysiology of renal allograft disease. Methods To explore metabolomic abnormalities in individuals with a failing kidney allograft, we analyzed by liquid chromatography-mass spectrometry (LC-MS/MS; for ex vivo profiling of serum and urine) and two dimensional correlated spectroscopy (2D COSY; for in vivo study of the kidney graft) 40 subjects with varying degrees of chronic allograft dysfunction stratified by tertiles of glomerular filtration rate (GFR; T1, T2, T3). Ten healthy non-allograft individuals were chosen as controls. Results LC-MS/MS analysis revealed a dose-response association between GFR and serum concentration of tryptophan, glutamine, dimethylarginine isomers (asymmetric [A]DMA and symmetric [S]DMA) and short-chain acylcarnitines (C4 and C12), (test for trend: T1-T3 = p<0.05; p = 0.01; p<0.001; p = 0.01; p = 0.01; p<0.05, respectively). The same association was found between GFR and urinary levels of histidine, DOPA, dopamine, carnosine, SDMA and ADMA (test for trend: T1-T3 = p<0.05; p<0.01; p = 0.001; p<0.05; p = 0.001; p<0.001; p<0.01, respectively). In vivo 2D COSY of the kidney allograft revealed significant reduction in the parenchymal content of choline, creatine, taurine and threonine (all: p<0.05) in individuals with lower GFR levels. Conclusions We report an association between renal function and altered metabolomic profile in renal transplant individuals with different degrees of kidney graft function. PMID:28052095
PsiQuaSP-A library for efficient computation of symmetric open quantum systems.
Gegg, Michael; Richter, Marten
2017-11-24
In a recent publication we showed that permutation symmetry reduces the numerical complexity of Lindblad quantum master equations for identical multi-level systems from exponential to polynomial scaling. This is important for open system dynamics including realistic system bath interactions and dephasing in, for instance, the Dicke model, multi-Λ system setups etc. Here we present an object-oriented C++ library that allows to setup and solve arbitrary quantum optical Lindblad master equations, especially those that are permutationally symmetric in the multi-level systems. PsiQuaSP (Permutation symmetry for identical Quantum Systems Package) uses the PETSc package for sparse linear algebra methods and differential equations as basis. The aim of PsiQuaSP is to provide flexible, storage efficient and scalable code while being as user friendly as possible. It is easily applied to many quantum optical or quantum information systems with more than one multi-level system. We first review the basics of the permutation symmetry for multi-level systems in quantum master equations. The application of PsiQuaSP to quantum dynamical problems is illustrated with several typical, simple examples of open quantum optical systems.
ISCE: A Modular, Reusable Library for Scalable SAR/InSAR Processing
NASA Astrophysics Data System (ADS)
Agram, P. S.; Lavalle, M.; Gurrola, E. M.; Sacco, G. F.; Rosen, P. A.
2016-12-01
Traditional community SAR/InSAR processing software tools have primarily focused on differential interferometry and Solid Earth applications. The InSAR Scientific Computing Environment (ISCE) was specifically designed to support the Earth Sciences user community as well as large scale operational processing tasks, thanks to its two-layered (Python+C/Fortran) architecture and modular framework. ISCE is freely distributed as a source tarball, allowing advanced users to modify and extend it for their research purposes and developing exploratory applications, while providing a relatively simple user interface for novice users to perform routine data analysis efficiently. Modular design of the ISCE library also enables easier development of applications to address the needs of Ecosystems, Cryosphere and Disaster Response communities in addition to the traditional Solid Earth applications. In this talk, we would like to emphasize the broader purview of the ISCE library and some of its unique features that sets it apart from other freely available community software like GMTSAR and DORIS, including: Support for multiple geometry regimes - Native Doppler (ALOS-1) as well Zero Doppler (ESA missions) systems. Support for data acquired by airborne platforms - e.g, JPL's UAVSAR and AirMOSS, DLR's F-SAR. Radiometric Terrain Correction - Auxiliary output layers from the geometry modules include projection angles, incidence angles, shadow-layover masks. Dense pixel offsets - Parallelized amplitude cross correlation for cryosphere / ionospheric correction applications. Rubber sheeting - Pixel-by-pixel offsets fields for resampling slave imagery for geometric co-registration/ ionospheric corrections. Preliminary Tandem-X processing support - Bistatic geometry modules. Extensibility to support other non-Solid Earth missions - Modules can be directly adopted for use with other SAR missions, e.g., SWOT. Preliminary support for multi-dimensional data products- multi-polarization, multi-frequency, multi-temporal, multi-baseline stacks via the PLANT and GIAnT toolboxes. Rapid prototyping - Geometry manipulation functionality at the python level allows users to prototype and test processing modules at the interpreter level before optimal implementation in C/C++/Fortran.
NASA Technical Reports Server (NTRS)
Drummond, Mark; Hine, Butler; Genet, Russell; Genet, David; Talent, David; Boyd, Louis; Trueblood, Mark; Filippenko, Alexei V. (Editor)
1991-01-01
The objective of multi-use telescopes is to reduce the initial and operational costs of space telescopes to the point where a fair number of telescopes, a dozen or so, would be affordable. The basic approach is to develop a common telescope, control system, and power and communications subsystem that can be used with a wide variety of instrument payloads, i.e., imaging CCD cameras, photometers, spectrographs, etc. By having such a multi-use and multi-user telescope, a common practice for earth-based telescopes, development cost can be shared across many telescopes, and the telescopes can be produced in economical batches.
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Schreckenghost, Debra L.; Woods, David D.; Potter, Scott S.; Johannesen, Leila; Holloway, Matthew; Forbus, Kenneth D.
1991-01-01
Initial results are reported from a multi-year, interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. The objective is to achieve more effective human-computer interaction (HCI) for systems with real time fault management capabilities. Intelligent fault management systems within the NASA were evaluated for insight into the design of systems with complex HCI. Preliminary results include: (1) a description of real time fault management in aerospace domains; (2) recommendations and examples for improving intelligent systems design and user interface design; (3) identification of issues requiring further research; and (4) recommendations for a development methodology integrating HCI design into intelligent system design.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Baker, Kyri A.; Christensen, Dane T.
This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Baker, Kyri A; Isley, Steven C
This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less
NASA Technical Reports Server (NTRS)
OMalley, Terence F.; Myhre, Craig A.
2000-01-01
The Fluids and Combustion Facility (FCF) is a multi-rack payload planned for the International Space Station (ISS) that will enable the study of fluid physics and combustion science in a microgravity environment. The Combustion Integrated Rack (CIR) is one of two International Standard Payload Racks of the FCF and is being designed primarily to support combustion science experiments. The Multi-user Droplet Combustion Apparatus (MDCA) is a multi-user apparatus designed to accommodate four different droplet combustion science experiments and is the first payload for CIR. The CIR will function independently until the later launch of the Fluids Integrated Rack component of the FCF. This paper provides an overview of the capabilities and the development status of the CIR and MDCA.
Mechanical System Analysis/Design Tool (MSAT) Quick Guide
NASA Technical Reports Server (NTRS)
Lee, HauHua; Kolb, Mark; Madelone, Jack
1998-01-01
MSAT is a unique multi-component multi-disciplinary tool that organizes design analysis tasks around object-oriented representations of configuration components, analysis programs and modules, and data transfer links between them. This creative modular architecture enables rapid generation of input stream for trade-off studies of various engine configurations. The data transfer links automatically transport output from one application as relevant input to the next application once the sequence is set up by the user. The computations are managed via constraint propagation - the constraints supplied by the user as part of any optimization module. The software can be used in the preliminary design stage as well as during the detail design of product development process.
Documenting clinical pharmacist intervention before and after the introduction of a web-based tool.
Nurgat, Zubeir A; Al-Jazairi, Abdulrazaq S; Abu-Shraie, Nada; Al-Jedai, Ahmed
2011-04-01
To develop a database for documenting pharmacist intervention through a web-based application. The secondary endpoint was to determine if the new, web-based application provides any benefits with regards to documentation compliance by clinical pharmacists and ease of calculating cost savings compared with our previous method of documenting pharmacist interventions. A tertiary care hospital in Saudi Arabia. The documentation of interventions using a web-based documentation application was retrospectively compared with previous methods of documentation of clinical pharmacists' interventions (multi-user PC software). The number and types of interventions recorded by pharmacists, data mining of archived data, efficiency, cost savings, and the accuracy of the data generated. The number of documented clinical interventions increased from 4,926, using the multi-user PC software, to 6,840 for the web-based application. On average, we observed 653 interventions per clinical pharmacist using the web-based application, which showed an increase compared to an average of 493 interventions using the old multi-user PC software. However, using a paired Student's t-test there was no statistical significance difference between the two means (P = 0.201). Using a χ² test, which captured management level and the type of system used, we found a strong effect of management level (P < 2.2 × 10⁻¹⁶) on the number of documented interventions. We also found a moderately significant relationship between educational level and the number of interventions documented (P = 0.045). The mean ± SD time required to document an intervention using the web-based application was 66.55 ± 8.98 s. Using the web-based application, 29.06% of documented interventions resulted in cost-savings, while using the multi-user PC software only 4.75% of interventions did so. The majority of cost savings across both platforms resulted from the discontinuation of unnecessary drugs and a change in dosage regimen. Data collection using the web-based application was consistently more complete when compared to the multi-user PC software. The web-based application is an efficient system for documenting pharmacist interventions. Its flexibility and accessibility, as well as its detailed report functionality is a useful tool that will hopefully encourage other primary and secondary care facilities to adopt similar applications.
Design of an imaging spectrometer for earth observation using freeform mirrors
NASA Astrophysics Data System (ADS)
Peschel, T.; Damm, C.; Beier, M.; Gebhardt, A.; Risse, S.; Walter, I.; Sebastian, I.; Krutz, D.
2017-09-01
In 2017 the new hyperspectral DLR Earth Sensing Imaging Spectrometer (DESIS) will be integrated in the Multi-User-System for Earth Sensing (MUSES) platform [1] installed on the International Space Station (ISS).
Wang, Zixiong; Yu, Changyuan; Zhong, Wen-De; Chen, Jian; Chen, Wei
2012-02-13
This paper investigates the performance of our recently proposed LED lamp arrangement to reduce the SNR fluctuation from different locations in the room for multi-user visible light communications. The LED lamp arrangement consists of 4 LED lamps positioned in the corners and 12 LED lamps spread evenly on a circle. Our studies show that the SNR fluctuation under such a LED lamp arrangement is reduced from 14.5 dB to 0.9 dB, which guarantees that users can obtain almost identical communication quality, regardless of their locations. After time domain zero-forcing (ZF) equalization, the BER performances and channel capacities of 100-Mbit/s and 200-Mbit/s bipolar on-off-keying (OOK) signal with most significant inter-symbol interference (ISI) are very close to that of the channel without any ISI caused by this LED lamp arrangement.
Abstract for 1999 Rational Software User Conference
NASA Technical Reports Server (NTRS)
Dunphy, Julia; Rouquette, Nicolas; Feather, Martin; Tung, Yu-Wen
1999-01-01
We develop spacecraft fault-protection software at NASA/JPL. Challenges exemplified by our task: 1) high-quality systems - need for extensive validation & verification; 2) multi-disciplinary context - involves experts from diverse areas; 3) embedded systems - must adapt to external practices, notations, etc.; and 4) development pressures - NASA's mandate of "better, faster, cheaper".
A system overview of the Aerospace Safety Research and Data Institute data management programs
NASA Technical Reports Server (NTRS)
1972-01-01
The NASA Aerospace Safety Information System, is an interactive, generalized data base management system. The on-line retrieval aspects provide for operating from a variety of terminals (or in batch mode). NASIS retrieval enables the user to expand and display (review) the terms of index (cross reference) files, select desired index terms, combine sets of documents corresponding to selected terms and display the resulting records. It also allows the user to print (record) this information on a high speed printer if desired. NASIS also provides the ability to store the strategy of any given session the user has executed. It has a searching and publication ability through generalized linear search and report generating modules which may be performed interactively or in a batch mode. The user may specify formats for the terminal from which he is operating. The system features an interactive user's guide which explains the various commands available and how to use them as well as explanations for all system messages. This explain capability may be extended, without program changes, to include descriptions of the various files in use. Coupled with the ability of NASIS to run in an MTT (multi-terminal task) mode is its automatic accumulation of statistics on each user of the system as well as each file.
2011-11-21
CAPE CANAVERAL, Fla. – Members of the media tour several facilities, including the Multi-Payload Processing Facility, during the 21st Century Ground Systems Program Tour at Kennedy Space Center in Florida. Other tour stops were the Launch Equipment Test Facility, the Operations & Checkout Building and the Canister Rotation Facility. NASA’s 21st Century Ground Systems Program was initiated at Kennedy Space Center to establish the needed launch and processing infrastructure to support the Space Launch System Program and to work toward transforming the landscape of the launch site for a multi-faceted user community. Photo credit: NASA/Jim Grossmann
2011-11-21
CAPE CANAVERAL, Fla. – Members of the media tour several facilities, including the Launch Equipment Test Facility in the Industrial Area, during the 21st Century Ground Systems Program Tour at Kennedy Space Center in Florida. Other tour stops were the Operations & Checkout Building, the Multi-Payload Processing Facility and the Canister Rotation Facility. NASA’s 21st Century Ground Systems Program was initiated at Kennedy Space Center to establish the needed launch and processing infrastructure to support the Space Launch System Program and to work toward transforming the landscape of the launch site for a multi-faceted user community. Photo credit: NASA/Jim Grossmann
2011-11-21
CAPE CANAVERAL, Fla. – Members of the media tour several facilities, including the Launch Equipment Test Facility in the Industrial Area, during the 21st Century Ground Systems Program Tour at Kennedy Space Center in Florida. Other tour stops were the Operations & Checkout Building, the Multi-Payload Processing Facility and the Canister Rotation Facility. NASA’s 21st Century Ground Systems Program was initiated at Kennedy Space Center to establish the needed launch and processing infrastructure to support the Space Launch System Program and to work toward transforming the landscape of the launch site for a multi-faceted user community. Photo credit: NASA/Jim Grossmann
Analysis of sDMA modifications of PIWI proteins
Honda, Shozo; Kirino, Yoriko; Kirino, Yohei
2015-01-01
Summary Arginine methylation is an important post-translational protein modification that modulates protein function for a wide range of biological processes. PIWI proteins, a subclade of the Argonaute family proteins, contain evolutionarily conserved symmetrical dimethylarginines (sDMAs). It has become increasingly apparent that the sDMAs of PIWI proteins serve as binding elements for TUDOR-domain containing proteins and that sDMA-dependent protein interactions play crucial roles in the biogenesis and function of PIWI-interacting RNAs (piRNAs). We describe a method for detecting PIWI sDMAs and purifying PIWI/piRNA complexes using anti-sDMA antibodies. PMID:24178562
Research on multi-user encrypted search scheme in cloud environment
NASA Astrophysics Data System (ADS)
Yu, Zonghua; Lin, Sui
2017-05-01
Aiming at the existing problems of multi-user encrypted search scheme in cloud computing environment, a basic multi-user encrypted scheme is proposed firstly, and then the basic scheme is extended to an anonymous hierarchical management authority. Compared with most of the existing schemes, the scheme not only to achieve the protection of keyword information, but also to achieve the protection of user identity privacy; the same time, data owners can directly control the user query permissions, rather than the cloud server. In addition, through the use of a special query key generation rules, to achieve the hierarchical management of the user's query permissions. The safety analysis shows that the scheme is safe and that the performance analysis and experimental data show that the scheme is practicable.
Zao, John K.; Gan, Tchin-Tze; You, Chun-Kai; Chung, Cheng-En; Wang, Yu-Te; Rodríguez Méndez, Sergio José; Mullen, Tim; Yu, Chieh; Kothe, Christian; Hsiao, Ching-Teng; Chu, San-Liang; Shieh, Ce-Kuen; Jung, Tzyy-Ping
2014-01-01
EEG-based Brain-computer interfaces (BCI) are facing basic challenges in real-world applications. The technical difficulties in developing truly wearable BCI systems that are capable of making reliable real-time prediction of users' cognitive states in dynamic real-life situations may seem almost insurmountable at times. Fortunately, recent advances in miniature sensors, wireless communication and distributed computing technologies offered promising ways to bridge these chasms. In this paper, we report an attempt to develop a pervasive on-line EEG-BCI system using state-of-art technologies including multi-tier Fog and Cloud Computing, semantic Linked Data search, and adaptive prediction/classification models. To verify our approach, we implement a pilot system by employing wireless dry-electrode EEG headsets and MEMS motion sensors as the front-end devices, Android mobile phones as the personal user interfaces, compact personal computers as the near-end Fog Servers and the computer clusters hosted by the Taiwan National Center for High-performance Computing (NCHC) as the far-end Cloud Servers. We succeeded in conducting synchronous multi-modal global data streaming in March and then running a multi-player on-line EEG-BCI game in September, 2013. We are currently working with the ARL Translational Neuroscience Branch to use our system in real-life personal stress monitoring and the UCSD Movement Disorder Center to conduct in-home Parkinson's disease patient monitoring experiments. We shall proceed to develop the necessary BCI ontology and introduce automatic semantic annotation and progressive model refinement capability to our system. PMID:24917804
Zao, John K; Gan, Tchin-Tze; You, Chun-Kai; Chung, Cheng-En; Wang, Yu-Te; Rodríguez Méndez, Sergio José; Mullen, Tim; Yu, Chieh; Kothe, Christian; Hsiao, Ching-Teng; Chu, San-Liang; Shieh, Ce-Kuen; Jung, Tzyy-Ping
2014-01-01
EEG-based Brain-computer interfaces (BCI) are facing basic challenges in real-world applications. The technical difficulties in developing truly wearable BCI systems that are capable of making reliable real-time prediction of users' cognitive states in dynamic real-life situations may seem almost insurmountable at times. Fortunately, recent advances in miniature sensors, wireless communication and distributed computing technologies offered promising ways to bridge these chasms. In this paper, we report an attempt to develop a pervasive on-line EEG-BCI system using state-of-art technologies including multi-tier Fog and Cloud Computing, semantic Linked Data search, and adaptive prediction/classification models. To verify our approach, we implement a pilot system by employing wireless dry-electrode EEG headsets and MEMS motion sensors as the front-end devices, Android mobile phones as the personal user interfaces, compact personal computers as the near-end Fog Servers and the computer clusters hosted by the Taiwan National Center for High-performance Computing (NCHC) as the far-end Cloud Servers. We succeeded in conducting synchronous multi-modal global data streaming in March and then running a multi-player on-line EEG-BCI game in September, 2013. We are currently working with the ARL Translational Neuroscience Branch to use our system in real-life personal stress monitoring and the UCSD Movement Disorder Center to conduct in-home Parkinson's disease patient monitoring experiments. We shall proceed to develop the necessary BCI ontology and introduce automatic semantic annotation and progressive model refinement capability to our system.
A 3D Freehand Ultrasound System for Multi-view Reconstructions from Sparse 2D Scanning Planes
2011-01-01
Background A significant limitation of existing 3D ultrasound systems comes from the fact that the majority of them work with fixed acquisition geometries. As a result, the users have very limited control over the geometry of the 2D scanning planes. Methods We present a low-cost and flexible ultrasound imaging system that integrates several image processing components to allow for 3D reconstructions from limited numbers of 2D image planes and multiple acoustic views. Our approach is based on a 3D freehand ultrasound system that allows users to control the 2D acquisition imaging using conventional 2D probes. For reliable performance, we develop new methods for image segmentation and robust multi-view registration. We first present a new hybrid geometric level-set approach that provides reliable segmentation performance with relatively simple initializations and minimum edge leakage. Optimization of the segmentation model parameters and its effect on performance is carefully discussed. Second, using the segmented images, a new coarse to fine automatic multi-view registration method is introduced. The approach uses a 3D Hotelling transform to initialize an optimization search. Then, the fine scale feature-based registration is performed using a robust, non-linear least squares algorithm. The robustness of the multi-view registration system allows for accurate 3D reconstructions from sparse 2D image planes. Results Volume measurements from multi-view 3D reconstructions are found to be consistently and significantly more accurate than measurements from single view reconstructions. The volume error of multi-view reconstruction is measured to be less than 5% of the true volume. We show that volume reconstruction accuracy is a function of the total number of 2D image planes and the number of views for calibrated phantom. In clinical in-vivo cardiac experiments, we show that volume estimates of the left ventricle from multi-view reconstructions are found to be in better agreement with clinical measures than measures from single view reconstructions. Conclusions Multi-view 3D reconstruction from sparse 2D freehand B-mode images leads to more accurate volume quantification compared to single view systems. The flexibility and low-cost of the proposed system allow for fine control of the image acquisition planes for optimal 3D reconstructions from multiple views. PMID:21251284
A 3D freehand ultrasound system for multi-view reconstructions from sparse 2D scanning planes.
Yu, Honggang; Pattichis, Marios S; Agurto, Carla; Beth Goens, M
2011-01-20
A significant limitation of existing 3D ultrasound systems comes from the fact that the majority of them work with fixed acquisition geometries. As a result, the users have very limited control over the geometry of the 2D scanning planes. We present a low-cost and flexible ultrasound imaging system that integrates several image processing components to allow for 3D reconstructions from limited numbers of 2D image planes and multiple acoustic views. Our approach is based on a 3D freehand ultrasound system that allows users to control the 2D acquisition imaging using conventional 2D probes.For reliable performance, we develop new methods for image segmentation and robust multi-view registration. We first present a new hybrid geometric level-set approach that provides reliable segmentation performance with relatively simple initializations and minimum edge leakage. Optimization of the segmentation model parameters and its effect on performance is carefully discussed. Second, using the segmented images, a new coarse to fine automatic multi-view registration method is introduced. The approach uses a 3D Hotelling transform to initialize an optimization search. Then, the fine scale feature-based registration is performed using a robust, non-linear least squares algorithm. The robustness of the multi-view registration system allows for accurate 3D reconstructions from sparse 2D image planes. Volume measurements from multi-view 3D reconstructions are found to be consistently and significantly more accurate than measurements from single view reconstructions. The volume error of multi-view reconstruction is measured to be less than 5% of the true volume. We show that volume reconstruction accuracy is a function of the total number of 2D image planes and the number of views for calibrated phantom. In clinical in-vivo cardiac experiments, we show that volume estimates of the left ventricle from multi-view reconstructions are found to be in better agreement with clinical measures than measures from single view reconstructions. Multi-view 3D reconstruction from sparse 2D freehand B-mode images leads to more accurate volume quantification compared to single view systems. The flexibility and low-cost of the proposed system allow for fine control of the image acquisition planes for optimal 3D reconstructions from multiple views.
Multi-Modal Traveler Information System - Information Clearinghouse Final Network
DOT National Transportation Integrated Search
1997-07-23
This Working Paper will summarize the lessons learned from the initial implementation of the Information Clearinghouse and outline the proposed configuration and functional capabilities of the Final Network. In addition, all new users added since Mar...
Optical CDMA components requirements
NASA Astrophysics Data System (ADS)
Chan, James K.
1998-08-01
Optical CDMA is a complementary multiple access technology to WDMA. Optical CDMA potentially provides a large number of virtual optical channels for IXC, LEC and CLEC or supports a large number of high-speed users in LAN. In a network, it provides asynchronous, multi-rate, multi-user communication with network scalability, re-configurability (bandwidth on demand), and network security (provided by inherent CDMA coding). However, optical CDMA technology is less mature in comparison to WDMA. The components requirements are also different from WDMA. We have demonstrated a video transport/switching system over a distance of 40 Km using discrete optical components in our laboratory. We are currently pursuing PIC implementation. In this paper, we will describe the optical CDMA concept/features, the demonstration system, and the requirements of some critical optical components such as broadband optical source, broadband optical amplifier, spectral spreading/de- spreading, and fixed/programmable mask.
1985-09-01
management and recurring reports generation . Included are the results of user interviews which were conducted to determine oossible system functions...9 A. GENERAL ...................... .......... 3 B. RESEARCH OBJECTIVES ............................ I0 C. SCOPE .. D... GENERAL DESCRIPTION (LAMPS) ...................... 9. LPMrOS CRGANIZAT r.N ............................... C. REPCRT>1NG RECLUIRE,’ENTS
Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis
NASA Astrophysics Data System (ADS)
Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario
2015-12-01
Objective. Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. Approach. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. Main results. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. Significance. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.
Sensor fusion and computer vision for context-aware control of a multi degree-of-freedom prosthesis.
Markovic, Marko; Dosen, Strahinja; Popovic, Dejan; Graimann, Bernhard; Farina, Dario
2015-12-01
Myoelectric activity volitionally generated by the user is often used for controlling hand prostheses in order to replicate the synergistic actions of muscles in healthy humans during grasping. Muscle synergies in healthy humans are based on the integration of visual perception, heuristics and proprioception. Here, we demonstrate how sensor fusion that combines artificial vision and proprioceptive information with the high-level processing characteristics of biological systems can be effectively used in transradial prosthesis control. We developed a novel context- and user-aware prosthesis (CASP) controller integrating computer vision and inertial sensing with myoelectric activity in order to achieve semi-autonomous and reactive control of a prosthetic hand. The presented method semi-automatically provides simultaneous and proportional control of multiple degrees-of-freedom (DOFs), thus decreasing overall physical effort while retaining full user control. The system was compared against the major commercial state-of-the art myoelectric control system in ten able-bodied and one amputee subject. All subjects used transradial prosthesis with an active wrist to grasp objects typically associated with activities of daily living. The CASP significantly outperformed the myoelectric interface when controlling all of the prosthesis DOF. However, when tested with less complex prosthetic system (smaller number of DOF), the CASP was slower but resulted with reaching motions that contained less compensatory movements. Another important finding is that the CASP system required minimal user adaptation and training. The CASP constitutes a substantial improvement for the control of multi-DOF prostheses. The application of the CASP will have a significant impact when translated to real-life scenarious, particularly with respect to improving the usability and acceptance of highly complex systems (e.g., full prosthetic arms) by amputees.
Make safety awareness a priority: Use a login software in your research facility
Camino, Fernando E.
2017-01-21
We report on a facility login software, whose objective is to improve safety in multi-user research facilities. Its most important safety features are: 1) blocks users from entering the lab after being absent for more than a predetermined number of days; 2) gives users a random safety quiz question, which they need to answer satisfactorily in order to use the facility; 3) blocks unauthorized users from using the facility afterhours; and 4) displays the current users in the facility. Besides restricting access to unauthorized users, the software keeps users mindful of key safety concepts. In addition, integration of the softwaremore » with a door controller system can convert it into an effective physical safety mechanism. Depending on DOE approval, the code may be available as open source.« less
Computer systems and methods for the query and visualization of multidimensional databases
Stolte, Chris; Tang, Diane L; Hanrahan, Patrick
2014-04-29
In response to a user request, a computer generates a graphical user interface on a computer display. A schema information region of the graphical user interface includes multiple operand names, each operand name associated with one or more fields of a multi-dimensional database. A data visualization region of the graphical user interface includes multiple shelves. Upon detecting a user selection of the operand names and a user request to associate each user-selected operand name with a respective shelf in the data visualization region, the computer generates a visual table in the data visualization region in accordance with the associations between the operand names and the corresponding shelves. The visual table includes a plurality of panes, each pane having at least one axis defined based on data for the fields associated with a respective operand name.
Computer systems and methods for the query and visualization of multidimensional databases
Stolte, Chris [Palo Alto, CA; Tang, Diane L [Palo Alto, CA; Hanrahan, Patrick [Portola Valley, CA
2011-02-01
In response to a user request, a computer generates a graphical user interface on a computer display. A schema information region of the graphical user interface includes multiple operand names, each operand name associated with one or more fields of a multi-dimensional database. A data visualization region of the graphical user interface includes multiple shelves. Upon detecting a user selection of the operand names and a user request to associate each user-selected operand name with a respective shelf in the data visualization region, the computer generates a visual table in the data visualization region in accordance with the associations between the operand names and the corresponding shelves. The visual table includes a plurality of panes, each pane having at least one axis defined based on data for the fields associated with a respective operand name.
Computer systems and methods for the query and visualization of multidimensional databases
Stolte, Chris [Palo Alto, CA; Tang, Diane L [Palo Alto, CA; Hanrahan, Patrick [Portola Valley, CA
2012-03-20
In response to a user request, a computer generates a graphical user interface on a computer display. A schema information region of the graphical user interface includes multiple operand names, each operand name associated with one or more fields of a multi-dimensional database. A data visualization region of the graphical user interface includes multiple shelves. Upon detecting a user selection of the operand names and a user request to associate each user-selected operand name with a respective shelf in the data visualization region, the computer generates a visual table in the data visualization region in accordance with the associations between the operand names and the corresponding shelves. The visual table includes a plurality of panes, each pane having at least one axis defined based on data for the fields associated with a respective operand name.
Make safety awareness a priority: Use a login software in your research facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Camino, Fernando E.
We report on a facility login software, whose objective is to improve safety in multi-user research facilities. Its most important safety features are: 1) blocks users from entering the lab after being absent for more than a predetermined number of days; 2) gives users a random safety quiz question, which they need to answer satisfactorily in order to use the facility; 3) blocks unauthorized users from using the facility afterhours; and 4) displays the current users in the facility. Besides restricting access to unauthorized users, the software keeps users mindful of key safety concepts. In addition, integration of the softwaremore » with a door controller system can convert it into an effective physical safety mechanism. Depending on DOE approval, the code may be available as open source.« less
University multi-user facility survey-2010.
Riley, Melissa B
2011-12-01
Multi-user facilities serve as a resource for many universities. In 2010, a survey was conducted investigating possible changes and successful characteristics of multi-user facilities, as well as identifying problems in facilities. Over 300 surveys were e-mailed to persons identified from university websites as being involved with multi-user facilities. Complete responses were received from 36 facilities with an average of 20 years of operation. Facilities were associated with specific departments (22%), colleges (22%), and university research centers (8.3%) or were not affiliated with any department or college within the university (47%). The five most important factors to succeed as a multi-user facility were: 1) maintaining an experienced, professional staff in an open atmosphere; 2) university-level support providing partial funding; 3) broad client base; 4) instrument training programs; and 5) an effective leader and engaged strategic advisory group. The most significant problems were: 1) inadequate university financial support and commitment; 2) problems recovering full service costs from university subsidies and user fees; 3) availability of funds to repair and upgrade equipment; 4) inability to retain highly qualified staff; and 5) unqualified users dirtying/damaging equipment. Further information related to these issues and to fee structure was solicited. Overall, there appeared to be a decline in university support for facilities and more emphasis on securing income by serving clients outside of the institution and by obtaining grants from entities outside of the university.
Small satellite multi mission C2 for maximum effect
Miller, E.; Medina, O.; Lane, C.R.; Kirkham, A.; Ivancic, W.; Jones, B.; Risty, R.
2006-01-01
This paper discusses US Air Force, US Army, US Navy, and NASA demonstrations based around the Virtual Mission Operations Center (VMOC) and its application in fielding a Multi Mission Satellite Operations Center (MMSOC) designed to integrate small satellites into the inherently tiered system environment of operations. The intent is to begin standardizing the spacecraft to ground interfaces needed to reduce costs, maximize space effects to the user, and allow the generation of Tactics, Techniques and Procedures (TTPs) that lead to Responsive Space employment. Combining the US Air Force/Army focus of theater command and control of payloads with the US Navy's user collaboration and FORCEnet consistent approach lays the groundwork for the fundamental change needed to maximize responsive space effects.
A multi-run chemistry module for the production of [18F]FDG
NASA Astrophysics Data System (ADS)
Sipe, B.; Murphy, M.; Best, B.; Zigler, S.; Lim, J.; Dorman, E.; Mangner, T.; Weichelt, M.
2001-07-01
We have developed a new chemistry module for the production of up to four batches of [18F]FDG. Prior to starting a batch sequence, the module automatically performs a series of self-diagnostic tests, including a reagent detection sequence. The module then executes a user-defined production sequence followed by an automated process to rinse tubing, valves, and the reaction vessel prior to the next production sequence. Process feedback from the module is provided to a graphical user interface by mass flow controllers, radiation detectors, a pressure switch, a pressure transducer, and an IR temperature sensor. This paper will describe the module, the operating system, and the results of multi-site trials, including production data and quality control results.
EPANET Multi-Species Extension Software and User's Manual ...
Software and User's Manual EPANET is used in homeland security research to model contamination threats to water systems. Historically, EPANET has been limited to tracking the dynamics of a single chemical transported through a network of pipes and storage tanks, such as a fluoride used in a tracer study or free chlorine used in a disinfection decay study. Recently, the NHSRC released a new extension to EPANET called EPANET-MSX (Multi-Species eXtension) that allows for the consideration of multiple interacting species in the bulk flow and on the pipe walls. This capability has been incorporated into both a stand-alone executable program as well as a toolkit library of functions that programmers can use to build customized applications.
Advancing MEMS Technology Usage through the MUMPS (Multi-User MEMS Processes) Program
NASA Technical Reports Server (NTRS)
Koester, D. A.; Markus, K. W.; Dhuler, V.; Mahadevan, R.; Cowen, A.
1995-01-01
In order to help provide access to advanced micro-electro-mechanical systems (MEMS) technologies and lower the barriers for both industry and academia, the Microelectronic Center of North Carolina (MCNC) and ARPA have developed a program which provides users with access to both MEMS processes and advanced electronic integration techniques. The four distinct aspects of this program, the multi-user MEMS processes (MUMP's), the consolidated micro-mechanical element library, smart MEMS, and the MEMS technology network are described in this paper. MUMP's is an ARPA-supported program created to provide inexpensive access to MEMS technology in a multi-user environment. It is both a proof-of-concept and educational tool that aids in the development of MEMS in the domestic community. MUMP's technologies currently include a 3-layer poly-silicon surface micromachining process and LIGA (lithography, electroforming, and injection molding) processes that provide reasonable design flexibility within set guidelines. The consolidated micromechanical element library (CaMEL) is a library of active and passive MEMS structures that can be downloaded by the MEMS community via the internet. Smart MEMS is the development of advanced electronics integration techniques for MEMS through the application of flip chip technology. The MEMS technology network (TechNet) is a menu of standard substrates and MEMS fabrication processes that can be purchased and combined to create unique process flows. TechNet provides the MEMS community greater flexibility and enhanced technology accessibility.
Dynamic quality of service differentiation using fixed code weight in optical CDMA networks
NASA Astrophysics Data System (ADS)
Kakaee, Majid H.; Essa, Shawnim I.; Abd, Thanaa H.; Seyedzadeh, Saleh
2015-11-01
The emergence of network-driven applications, such as internet, video conferencing, and online gaming, brings in the need for a network the environments with capability of providing diverse Quality of Services (QoS). In this paper, a new code family of novel spreading sequences, called a Multi-Service (MS) code, has been constructed to support multiple services in Optical- Code Division Multiple Access (CDMA) system. The proposed method uses fixed weight for all services, however reducing the interfering codewords for the users requiring higher QoS. The performance of the proposed code is demonstrated using mathematical analysis. It shown that the total number of served users with satisfactory BER of 10-9 using NB=2 is 82, while they are only 36 and 10 when NB=3 and 4 respectively. The developed MS code is compared with variable-weight codes such as Variable Weight-Khazani Syed (VW-KS) and Multi-Weight-Random Diagonal (MW-RD). Different numbers of basic users (NB) are used to support triple-play services (audio, data and video) with different QoS requirements. Furthermore, reference to the BER of 10-12, 10-9, and 10-3 for video, data and audio, respectively, the system can support up to 45 total users. Hence, results show that the technique can clearly provide a relative QoS differentiation with lower value of basic users can support larger number of subscribers as well as better performance in terms of acceptable BER of 10-9 at fixed code weight.
Emotion-prints: interaction-driven emotion visualization on multi-touch interfaces
NASA Astrophysics Data System (ADS)
Cernea, Daniel; Weber, Christopher; Ebert, Achim; Kerren, Andreas
2015-01-01
Emotions are one of the unique aspects of human nature, and sadly at the same time one of the elements that our technological world is failing to capture and consider due to their subtlety and inherent complexity. But with the current dawn of new technologies that enable the interpretation of emotional states based on techniques involving facial expressions, speech and intonation, electrodermal response (EDS) and brain-computer interfaces (BCIs), we are finally able to access real-time user emotions in various system interfaces. In this paper we introduce emotion-prints, an approach for visualizing user emotional valence and arousal in the context of multi-touch systems. Our goal is to offer a standardized technique for representing user affective states in the moment when and at the location where the interaction occurs in order to increase affective self-awareness, support awareness in collaborative and competitive scenarios, and offer a framework for aiding the evaluation of touch applications through emotion visualization. We show that emotion-prints are not only independent of the shape of the graphical objects on the touch display, but also that they can be applied regardless of the acquisition technique used for detecting and interpreting user emotions. Moreover, our representation can encode any affective information that can be decomposed or reduced to Russell's two-dimensional space of valence and arousal. Our approach is enforced by a BCI-based user study and a follow-up discussion of advantages and limitations.
Li, Song; Cui, Jie; Zhong, Hong; Liu, Lu
2017-05-05
Wireless Body Sensor Networks (WBSNs) are gaining importance in the era of the Internet of Things (IoT). The modern medical system is a particular area where the WBSN techniques are being increasingly adopted for various fundamental operations. Despite such increasing deployments of WBSNs, issues such as the infancy in the size, capabilities and limited data processing capacities of the sensor devices restrain their adoption in resource-demanding applications. Though providing computing and storage supplements from cloud servers can potentially enrich the capabilities of the WBSNs devices, data security is one of the prevailing issues that affects the reliability of cloud-assisted services. Sensitive applications such as modern medical systems demand assurance of the privacy of the users' medical records stored in distant cloud servers. Since it is economically impossible to set up private cloud servers for every client, auditing data security managed in the remote servers has necessarily become an integral requirement of WBSNs' applications relying on public cloud servers. To this end, this paper proposes a novel certificateless public auditing scheme with integrated privacy protection. The multi-user model in our scheme supports groups of users to store and share data, thus exhibiting the potential for WBSNs' deployments within community environments. Furthermore, our scheme enriches user experiences by offering public verifiability, forward security mechanisms and revocation of illegal group members. Experimental evaluations demonstrate the security effectiveness of our proposed scheme under the Random Oracle Model (ROM) by outperforming existing cloud-assisted WBSN models.
Managing multicentre clinical trials with open source.
Raptis, Dimitri Aristotle; Mettler, Tobias; Fischer, Michael Alexander; Patak, Michael; Lesurtel, Mickael; Eshmuminov, Dilmurodjon; de Rougemont, Olivier; Graf, Rolf; Clavien, Pierre-Alain; Breitenstein, Stefan
2014-03-01
Multicentre clinical trials are challenged by high administrative burden, data management pitfalls and costs. This leads to a reduced enthusiasm and commitment of the physicians involved and thus to a reluctance in conducting multicentre clinical trials. The purpose of this study was to develop a web-based open source platform to support a multi-centre clinical trial. We developed on Drupal, an open source software distributed under the terms of the General Public License, a web-based, multi-centre clinical trial management system with the design science research approach. This system was evaluated by user-testing and well supported several completed and on-going clinical trials and is available for free download. Open source clinical trial management systems are capable in supporting multi-centre clinical trials by enhancing efficiency, quality of data management and collaboration.
Development of MPEG standards for 3D and free viewpoint video
NASA Astrophysics Data System (ADS)
Smolic, Aljoscha; Kimata, Hideaki; Vetro, Anthony
2005-11-01
An overview of 3D and free viewpoint video is given in this paper with special focus on related standardization activities in MPEG. Free viewpoint video allows the user to freely navigate within real world visual scenes, as known from virtual worlds in computer graphics. Suitable 3D scene representation formats are classified and the processing chain is explained. Examples are shown for image-based and model-based free viewpoint video systems, highlighting standards conform realization using MPEG-4. Then the principles of 3D video are introduced providing the user with a 3D depth impression of the observed scene. Example systems are described again focusing on their realization based on MPEG-4. Finally multi-view video coding is described as a key component for 3D and free viewpoint video systems. MPEG is currently working on a new standard for multi-view video coding. The conclusion is that the necessary technology including standard media formats for 3D and free viewpoint is available or will be available in the near future, and that there is a clear demand from industry and user side for such applications. 3DTV at home and free viewpoint video on DVD will be available soon, and will create huge new markets.
Concept-Based Grammatical Errors of Arab EFL Learners
ERIC Educational Resources Information Center
Al-Quran, Majed
2010-01-01
Building up messages as a cognitive activity within the linguistic multi-level system is the result of the interaction between the various components of this system. Yet, this interactive process occurring in the language user's mind while encoding can vary from person to person. Likewise, it also differs in different recipients while decoding.…
Assessment User Guide for Colleges and Universities
ERIC Educational Resources Information Center
American Association of Collegiate Registrars and Admissions Officers (AACRAO), 2015
2015-01-01
The Smarter Balanced Assessment Consortium is one of two multi-state consortia that have built new assessment systems aligned to the Common Core State Standards. The Smarter Balanced Assessment Consortium is composed of 18 states and the U.S. Virgin Islands that have worked together to develop a comprehensive assessment system aligned to the…
YASS: A System Simulator for Operating System and Computer Architecture Teaching and Learning
ERIC Educational Resources Information Center
Mustafa, Besim
2013-01-01
A highly interactive, integrated and multi-level simulator has been developed specifically to support both the teachers and the learners of modern computer technologies at undergraduate level. The simulator provides a highly visual and user configurable environment with many pedagogical features aimed at facilitating deep understanding of concepts…
Mobile-IT Education (MIT.EDU): M-Learning Applications for Classroom Settings
ERIC Educational Resources Information Center
Sung, M.; Gips, J.; Eagle, N.; Madan, A.; Caneel, R.; DeVaul, R.; Bonsen, J.; Pentland, A.
2005-01-01
In this paper, we describe the Mobile-IT Education (MIT.EDU) system, which demonstrates the potential of using a distributed mobile device architecture for rapid prototyping of wireless mobile multi-user applications for use in classroom settings. MIT.EDU is a stable, accessible system that combines inexpensive, commodity hardware, a flexible…
Integrated multisensor perimeter detection systems
NASA Astrophysics Data System (ADS)
Kent, P. J.; Fretwell, P.; Barrett, D. J.; Faulkner, D. A.
2007-10-01
The report describes the results of a multi-year programme of research aimed at the development of an integrated multi-sensor perimeter detection system capable of being deployed at an operational site. The research was driven by end user requirements in protective security, particularly in threat detection and assessment, where effective capability was either not available or prohibitively expensive. Novel video analytics have been designed to provide robust detection of pedestrians in clutter while new radar detection and tracking algorithms provide wide area day/night surveillance. A modular integrated architecture based on commercially available components has been developed. A graphical user interface allows intuitive interaction and visualisation with the sensors. The fusion of video, radar and other sensor data provides the basis of a threat detection capability for real life conditions. The system was designed to be modular and extendable in order to accommodate future and legacy surveillance sensors. The current sensor mix includes stereoscopic video cameras, mmWave ground movement radar, CCTV and a commercially available perimeter detection cable. The paper outlines the development of the system and describes the lessons learnt after deployment in a pilot trial.
Multi-Level Adaptation in End-User Development of 3D Virtual Chemistry Experiments
ERIC Educational Resources Information Center
Liu, Chang; Zhong, Ying
2014-01-01
Multi-level adaptation in end-user development (EUD) is an effective way to enable non-technical end users such as educators to gradually introduce more functionality with increasing complexity to 3D virtual learning environments developed by themselves using EUD approaches. Parameterization, integration, and extension are three levels of…
LinkWinds: An Approach to Visual Data Analysis
NASA Technical Reports Server (NTRS)
Jacobson, Allan S.
1992-01-01
The Linked Windows Interactive Data System (LinkWinds) is a prototype visual data exploration and analysis system resulting from a NASA/JPL program of research into graphical methods for rapidly accessing, displaying and analyzing large multivariate multidisciplinary datasets. It is an integrated multi-application execution environment allowing the dynamic interconnection of multiple windows containing visual displays and/or controls through a data-linking paradigm. This paradigm, which results in a system much like a graphical spreadsheet, is not only a powerful method for organizing large amounts of data for analysis, but provides a highly intuitive, easy to learn user interface on top of the traditional graphical user interface.
Multi-subject subspace alignment for non-stationary EEG-based emotion recognition.
Chai, Xin; Wang, Qisong; Zhao, Yongping; Liu, Xin; Liu, Dan; Bai, Ou
2018-01-01
Emotion recognition based on EEG signals is a critical component in Human-Machine collaborative environments and psychiatric health diagnoses. However, EEG patterns have been found to vary across subjects due to user fatigue, different electrode placements, and varying impedances, etc. This problem renders the performance of EEG-based emotion recognition highly specific to subjects, requiring time-consuming individual calibration sessions to adapt an emotion recognition system to new subjects. Recently, domain adaptation (DA) strategies have achieved a great deal success in dealing with inter-subject adaptation. However, most of them can only adapt one subject to another subject, which limits their applicability in real-world scenarios. To alleviate this issue, a novel unsupervised DA strategy called Multi-Subject Subspace Alignment (MSSA) is proposed in this paper, which takes advantage of subspace alignment solution and multi-subject information in a unified framework to build personalized models without user-specific labeled data. Experiments on a public EEG dataset known as SEED verify the effectiveness and superiority of MSSA over other state of the art methods for dealing with multi-subject scenarios.
Makulska, Irena; Szczepańska, Maria; Drożdż, Dorota; Polak-Jonkisz, Dorota; Zwolińska, Danuta
2015-05-01
Skin autofluorescence (sAF) was examined as a marker of the accumulation of advanced glycation end products (AGEs) in tissues of children with chronic kidney disease (CKD) in relation to renal function, dialysis modality and markers of endothelial inflammation and dysfunction. A total of 76 children with CKD were enrolled in the study, of whom 20 children were on hemodialysis (HD), 20 were on peritoneal dialysis (PD) and 36 were treated conservatively. A control group of 26 healthy subjects was also included in the study. In all children, sAF intensity, carotid intima-media (cIMT) thickness and plasma concentrations of sE-selectin, matrix metalloproteinase 9 (MMP-9), tissue inhibitor of metalloproteinase 1 (TIMP-1), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and plasminogen activator inhibitor type 1 (PAI-1) were measured. Compared to the controls, children with CKD had significantly elevated sAF levels. sAF in the children with CKD was positively correlated with sE-selectin, MMP-9, TIMP-1, ADMA, SDMA and PAI-1 levels. In the predialysis group (conservative treatment) sAF levels were positively correlated with sE-selectin and ADMA levels and negatively correlated with glomerular filtration rate. Multiple regression analysis showed a significant association of sAF with sE-selectin and MMP-9 in CKD children. The results reveal that AGEs were accumulated in the children with CKD. This accumulation was related to early vascular changes and a number of biochemical vascular risk markers. sAF measurement, as a noninvasive method, may be useful for identification of clinical risk factors of vascular disease in CKD children.
Arginine-Nitric Oxide Metabolites and Cardiac Dysfunction in Patients With Breast Cancer.
Finkelman, Brian S; Putt, Mary; Wang, Teresa; Wang, Le; Narayan, Hari; Domchek, Susan; DeMichele, Angela; Fox, Kevin; Matro, Jennifer; Shah, Payal; Clark, Amy; Bradbury, Angela; Narayan, Vivek; Carver, Joseph R; Tang, W H Wilson; Ky, Bonnie
2017-07-11
Oxidative/nitrosative stress and endothelial dysfunction are hypothesized to be central to cancer therapeutics-related cardiac dysfunction (CTRCD). However, the relationship between circulating arginine-nitric oxide (NO) metabolites and CTRCD remains unstudied. This study sought to examine the relationship between arginine-NO metabolites and CTRCD in a prospective cohort of 170 breast cancer patients treated with doxorubicin with or without trastuzumab. Plasma levels of arginine, citrulline, ornithine, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and N-monomethylarginine (MMA) were quantified at baseline, 1 month, and 2 months after doxorubicin initiation. Determinants of baseline biomarker levels were identified using multivariable linear regression, and Cox regression defined the association between baseline levels and 1- or 2-month biomarker changes and CTRCD rate in 139 participants with quantitated echocardiograms at all time points. Age, hypertension, body mass index, and African-American race were independently associated with ≥1 of baseline citrulline, ADMA, SDMA, and MMA levels. Decreases in arginine and citrulline and increases in ADMA were observed at 1 and 2 months (all p < 0.05). Overall, 32 participants experienced CTRCD over a maximum follow-up of 5.4 years. Hazard ratios for ADMA and MMA at 2 months were 3.33 (95% confidence interval [CI]: 1.12 to 9.96) and 2.70 (95% CI: 1.35 to 5.41), respectively, and 0.78 (95% CI: 0.64 to 0.97) for arginine at 1 month. In breast cancer patients undergoing doxorubicin therapy, early alterations in arginine-NO metabolite levels occurred, and early biomarker changes were associated with a greater CTRCD rate. Our findings highlight the potential mechanistic and translational relevance of this pathway to CTRCD. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Effects of prior aerobic exercise on sitting-induced vascular dysfunction in healthy men.
Ballard, Kevin D; Duguid, Robert M; Berry, Craig W; Dey, Priyankar; Bruno, Richard S; Ward, Rose Marie; Timmerman, Kyle L
2017-12-01
Acute aerobic exercise prevents sitting-induced impairment of flow-mediated dilation (FMD). Further, evidence suggests that sitting-induced impairment of FMD occurs via an oxidative stress-dependent mechanism that disrupts endothelial function. We hypothesized that acute aerobic exercise would prevent impairment of femoral artery FMD by limiting oxidative stress responses that increase endothelin-1 (ET-1) levels and disrupt nitric oxide (NO) status. In a randomized, cross-over study, healthy men (n = 11; 21.2 ± 1.9 years) completed two 3 h sitting trials that were preceded by 45 min of either quiet rest (REST) or a single bout of continuous treadmill exercise (65% maximal oxygen consumption) (EX). Superficial femoral artery FMD, plasma glucose, malondialdehyde (MDA), ET-1, arginine (ARG) and its related metabolites [homoarginine (HA), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA)] were assessed at baseline, 1 h following EX (or REST) (0 h), and at 1 h intervals during 3 h of uninterrupted sitting. Data were analyzed using repeated measures ANOVA. During REST, femoral artery FMD declined from baseline (2.6 ± 1.8%) at 1, 2, and 3 h of sitting and resting shear rate decreased at 3 h. In contrast, when sitting was preceded by EX, femoral artery FMD (2.7 ± 2.0%) and resting shear rate responses were unaffected. No between trial differences were detected for plasma glucose, MDA, ET-1, ARG, HA, ADMA, or SDMA. Prior aerobic exercise prevented the decline in femoral artery FMD that is otherwise induced by prolonged sitting independent of changes in oxidative stress, ET-1, and NO status.
Epigenetic control via allosteric regulation of mammalian protein arginine methyltransferases.
Jain, Kanishk; Jin, Cyrus Y; Clarke, Steven G
2017-09-19
Arginine methylation on histones is a central player in epigenetics and in gene activation and repression. Protein arginine methyltransferase (PRMT) activity has been implicated in stem cell pluripotency, cancer metastasis, and tumorigenesis. The expression of one of the nine mammalian PRMTs, PRMT5, affects the levels of symmetric dimethylarginine (SDMA) at Arg-3 on histone H4, leading to the repression of genes which are related to disease progression in lymphoma and leukemia. Another PRMT, PRMT7, also affects SDMA levels at the same site despite its unique monomethylating activity and the lack of any evidence for PRMT7-catalyzed histone H4 Arg-3 methylation. We present evidence that PRMT7-mediated monomethylation of histone H4 Arg-17 regulates PRMT5 activity at Arg-3 in the same protein. We analyzed the kinetics of PRMT5 over a wide range of substrate concentrations. Significantly, we discovered that PRMT5 displays positive cooperativity in vitro, suggesting that this enzyme may be allosterically regulated in vivo as well. Most interestingly, monomethylation at Arg-17 in histone H4 not only raised the general activity of PRMT5 with this substrate, but also ameliorated the low activity of PRMT5 at low substrate concentrations. These kinetic studies suggest a biochemical explanation for the interplay between PRMT5- and PRMT7-mediated methylation of the same substrate at different residues and also suggest a general model for regulation of PRMTs. Elucidating the exact relationship between these two enzymes when they methylate two distinct sites of the same substrate may aid in developing therapeutics aimed at reducing PRMT5/7 activity in cancer and other diseases.
Epigenetic control via allosteric regulation of mammalian protein arginine methyltransferases
Jin, Cyrus Y.; Clarke, Steven G.
2017-01-01
Arginine methylation on histones is a central player in epigenetics and in gene activation and repression. Protein arginine methyltransferase (PRMT) activity has been implicated in stem cell pluripotency, cancer metastasis, and tumorigenesis. The expression of one of the nine mammalian PRMTs, PRMT5, affects the levels of symmetric dimethylarginine (SDMA) at Arg-3 on histone H4, leading to the repression of genes which are related to disease progression in lymphoma and leukemia. Another PRMT, PRMT7, also affects SDMA levels at the same site despite its unique monomethylating activity and the lack of any evidence for PRMT7-catalyzed histone H4 Arg-3 methylation. We present evidence that PRMT7-mediated monomethylation of histone H4 Arg-17 regulates PRMT5 activity at Arg-3 in the same protein. We analyzed the kinetics of PRMT5 over a wide range of substrate concentrations. Significantly, we discovered that PRMT5 displays positive cooperativity in vitro, suggesting that this enzyme may be allosterically regulated in vivo as well. Most interestingly, monomethylation at Arg-17 in histone H4 not only raised the general activity of PRMT5 with this substrate, but also ameliorated the low activity of PRMT5 at low substrate concentrations. These kinetic studies suggest a biochemical explanation for the interplay between PRMT5- and PRMT7-mediated methylation of the same substrate at different residues and also suggest a general model for regulation of PRMTs. Elucidating the exact relationship between these two enzymes when they methylate two distinct sites of the same substrate may aid in developing therapeutics aimed at reducing PRMT5/7 activity in cancer and other diseases. PMID:28874563
Performance of Rapid Diagnostic Tests for Plasmodium ovale Malaria in Japanese Travellers
Tanizaki, Ryutaro; Kato, Yasuyuki; Iwagami, Moritoshi; Kutsuna, Satoshi; Ujiie, Mugen; Takeshita, Nozomi; Hayakawa, Kayoko; Kanagawa, Shuzo; Kano, Shigeyuki; Ohmagari, Norio
2014-01-01
Background: Rapid diagnostic tests (RDTs) are used widely in the diagnosis of malaria. Although the effectiveness of RDTs for malaria has been described in many previous studies, the low performance of RDT particularly for Plasmodium ovale malaria in traveller has rarely been reported. Methods: This was a retrospective cohort study conducted on Japanese travellers diagnosed with malaria at the National Center for Global Health and Medicine between January 2004 and June 2013. The diagnosis of malaria was confirmed by microscopic examination, RDT, and polymerase chain reaction in all patients. The RDTs used in our study were Binax NOW Malaria (Binax Inc., Scarborough, Maine, USA) (BN) and SD Malaria Antigen Pf/Pan (Standard Diagnostics Inc., Korea) (SDMA). We compared the sensitivity of the RDTs to P. ovale malaria and Plasmodium vivax malaria. Results: A total of 153 cases of malaria were observed, 113 of which were found among Japanese travellers. Nine patients with P. ovale malaria and 17 patients with P. vivax malaria undergoing RDTs were evaluated. The overall sensitivity of RDTs for P. ovale malaria and P. vivax malaria was 22.2% and 94.1%, respectively (P < 0.001). The sensitivity of SDMA for P. ovale malaria and P. vivax malaria was 50% and 100%, respectively. The sensitivity of BN for P. vivax malaria was 90.0%, but it was ineffective in detecting the cases of P. ovale malaria. Conclusions: The sensitivity of RDTs was not high enough to diagnose P. ovale malaria in our study. In order not to overlook P. ovale malaria, therefore, microscopic examination is indispensable. PMID:25473374
Kinect the dots: 3D control of optical tweezers
NASA Astrophysics Data System (ADS)
Shaw, Lucy; Preece, Daryl; Rubinsztein-Dunlop, Halina
2013-07-01
Holographically generated optical traps confine micron- and sub-micron sized particles close to the center of focused light beams. They also provide a way of trapping multiple particles and moving them in three dimensions. However, in many systems the user interface is not always advantageous or intuitive especially for collaborative work and when depth information is required. We discuss and evaluate a set of multi-beam optical tweezers that utilize off the shelf gaming technology to facilitate user interaction. We use the Microsoft Kinect sensor bar as a way of getting the user input required to generate arbitrary optical force fields and control optically trapped particles. We demonstrate that the system can also be used for dynamic light control.
Dynamic image fusion and general observer preference
NASA Astrophysics Data System (ADS)
Burks, Stephen D.; Doe, Joshua M.
2010-04-01
Recent developments in image fusion give the user community many options for ways of presenting the imagery to an end-user. Individuals at the US Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate have developed an electronic system that allows users to quickly and efficiently determine optimal image fusion algorithms and color parameters based upon collected imagery and videos from environments that are typical to observers in a military environment. After performing multiple multi-band data collections in a variety of military-like scenarios, different waveband, fusion algorithm, image post-processing, and color choices are presented to observers as an output of the fusion system. The observer preferences can give guidelines as to how specific scenarios should affect the presentation of fused imagery.
On the Multi-Modal Object Tracking and Image Fusion Using Unsupervised Deep Learning Methodologies
NASA Astrophysics Data System (ADS)
LaHaye, N.; Ott, J.; Garay, M. J.; El-Askary, H. M.; Linstead, E.
2017-12-01
The number of different modalities of remote-sensors has been on the rise, resulting in large datasets with different complexity levels. Such complex datasets can provide valuable information separately, yet there is a bigger value in having a comprehensive view of them combined. As such, hidden information can be deduced through applying data mining techniques on the fused data. The curse of dimensionality of such fused data, due to the potentially vast dimension space, hinders our ability to have deep understanding of them. This is because each dataset requires a user to have instrument-specific and dataset-specific knowledge for optimum and meaningful usage. Once a user decides to use multiple datasets together, deeper understanding of translating and combining these datasets in a correct and effective manner is needed. Although there exists data centric techniques, generic automated methodologies that can potentially solve this problem completely don't exist. Here we are developing a system that aims to gain a detailed understanding of different data modalities. Such system will provide an analysis environment that gives the user useful feedback and can aid in research tasks. In our current work, we show the initial outputs our system implementation that leverages unsupervised deep learning techniques so not to burden the user with the task of labeling input data, while still allowing for a detailed machine understanding of the data. Our goal is to be able to track objects, like cloud systems or aerosols, across different image-like data-modalities. The proposed system is flexible, scalable and robust to understand complex likenesses within multi-modal data in a similar spatio-temporal range, and also to be able to co-register and fuse these images when needed.
Tactical Operations Analysis Support Facility.
1981-05-01
Punch/Reader 2 DMC-11AR DDCMP Micro Processor 2 DMC-11DA Network Link Line Unit 2 DL-11E Async Serial Line Interface 4 Intel IN-1670 448K Words MOS Memory...86 5.3 VIRTUAL PROCESSORS - VAX-11/750 ........................... 89 5.4 A RELATIONAL DATA MANAGEMENT SYSTEM - ORACLE...Central Processing Unit (CPU) is a 16 bit processor for high-speed, real time applications, and for large multi-user, multi- task, time shared
Self-Encoded Spread Spectrum Modulation for Robust Anti-Jamming Communication
2009-06-30
experience in both theoretical and experimental aspects of RF and optical communications, multi-user CDMA systems, transmitter precoding and code...the performance of DS - and FH-SESS modulation in the presence of worst-case jamming, develop innovative SESS schemes that further exploit time and...Determine BER and AJ performance of the feedback and iterative detectors in DS -SESS under pulsed-noise and multi-tone jamming • Task 2: Develop a scheme
Generalized Advanced Propeller Analysis System (GAPAS). Volume 2: Computer program user manual
NASA Technical Reports Server (NTRS)
Glatt, L.; Crawford, D. R.; Kosmatka, J. B.; Swigart, R. J.; Wong, E. W.
1986-01-01
The Generalized Advanced Propeller Analysis System (GAPAS) computer code is described. GAPAS was developed to analyze advanced technology multi-bladed propellers which operate on aircraft with speeds up to Mach 0.8 and altitudes up to 40,000 feet. GAPAS includes technology for analyzing aerodynamic, structural, and acoustic performance of propellers. The computer code was developed for the CDC 7600 computer and is currently available for industrial use on the NASA Langley computer. A description of all the analytical models incorporated in GAPAS is included. Sample calculations are also described as well as users requirements for modifying the analysis system. Computer system core requirements and running times are also discussed.
NASA Astrophysics Data System (ADS)
Teng, W.; Berrick, S.; Leptoukh, G.; Liu, Z.; Rui, H.; Pham, L.; Shen, S.; Zhu, T.
2004-12-01
The Goddard Space Flight Center Earth Sciences Data and Information Services Center (GES DISC) Distributed Active Archive Center (DAAC) is developing an Agricultural Information System (AIS), evolved from an existing TRMM Online Visualization and Analysis System (TOVAS), which will operationally provide precipitation and other satellite data products and services. AIS outputs will be integrated into existing operational decision support systems for global crop monitoring, such as that of the U.N. World Food Program. The ability to use the raw data stored in the GES DAAC archives is highly dependent on having a detailed understanding of the data's internal structure and physical implementation. To gain this understanding is a time-consuming process and not a productive investment of the user's time. This is an especially difficult challenge when users need to deal with multi-sensor data that usually are of different structures and resolutions. The AIS has taken a major step towards meeting this challenge by incorporating an underlying infrastructure, called the GES-DISC Interactive Online Visualization and Analysis Infrastructure or "Giovanni," that integrates various components to support web interfaces that allow users to perform interactive analysis on-line without downloading any data. Several instances of the Giovanni-based interface have been or are being created to serve users of TRMM precipitation, MODIS aerosol, and SeaWiFS ocean color data, as well as agricultural applications users. Giovanni-based interfaces are simple to use but powerful. The user selects geophysical parameters, area of interest, and time period; and the system generates an output on screen in a matter of seconds. The currently available output options are (1) area plot - averaged or accumulated over any available data period for any rectangular area; (2) time plot - time series averaged over any rectangular area; (3) Hovmoller plots - longitude-time and latitude-time plots; (4) ASCII output - for all plot types; and (5) image animation - for area plot. Planned output options for the near-future include correlation plots and GIS-compatible outputs. The AIS will enable the remote, interoperable access to distributed data, because the current Giovanni implementation incorporates the GrADS-DODS Server (GDS), a stable, secure data server that provides subsetting and analysis services across the Internet, for any GrADS-readable data set. The subsetting capability allows users to retrieve a specified spatial region from a large data set, eliminating the need to first download the entire data set. The analysis capability allows users to retrieve the results of an operation applied to one or more data sets on the server. The Giovanni-GDS technology allows the serving of data, through convenient on-line analysis tools, from any location where GDS and a few GrADS scripts are installed. The GES-DISC implementation of this technology is unique in the way it enables multi-sensor processing and analysis.
Agreement Technologies for Energy Optimization at Home.
González-Briones, Alfonso; Chamoso, Pablo; De La Prieta, Fernando; Demazeau, Yves; Corchado, Juan M
2018-05-19
Nowadays, it is becoming increasingly common to deploy sensors in public buildings or homes with the aim of obtaining data from the environment and taking decisions that help to save energy. Many of the current state-of-the-art systems make decisions considering solely the environmental factors that cause the consumption of energy. These systems are successful at optimizing energy consumption; however, they do not adapt to the preferences of users and their comfort. Any system that is to be used by end-users should consider factors that affect their wellbeing. Thus, this article proposes an energy-saving system, which apart from considering the environmental conditions also adapts to the preferences of inhabitants. The architecture is based on a Multi-Agent System (MAS), its agents use Agreement Technologies (AT) to perform a negotiation process between the comfort preferences of the users and the degree of optimization that the system can achieve according to these preferences. A case study was conducted in an office building, showing that the proposed system achieved average energy savings of 17.15%.
Multi-modal virtual environment research at Armstrong Laboratory
NASA Technical Reports Server (NTRS)
Eggleston, Robert G.
1995-01-01
One mission of the Paul M. Fitts Human Engineering Division of Armstrong Laboratory is to improve the user interface for complex systems through user-centered exploratory development and research activities. In support of this goal, many current projects attempt to advance and exploit user-interface concepts made possible by virtual reality (VR) technologies. Virtual environments may be used as a general purpose interface medium, an alternative display/control method, a data visualization and analysis tool, or a graphically based performance assessment tool. An overview is given of research projects within the division on prototype interface hardware/software development, integrated interface concept development, interface design and evaluation tool development, and user and mission performance evaluation tool development.
Hackländer, T; Kleber, K; Schneider, H; Demabre, N; Cramer, B M
2004-08-01
To build an infrastructure that enables radiologists on-call and external users a teleradiological access to the HTML-based image distribution system inside the hospital via internet. In addition, no investment costs should arise on the user side and the image data should be sent renamed using cryptographic techniques. A pure HTML-based system manages the image distribution inside the hospital, with an open source project extending this system through a secure gateway outside the firewall of the hospital. The gateway handles the communication between the external users and the HTML server within the network of the hospital. A second firewall is installed between the gateway and the external users and builds up a virtual private network (VPN). A connection between the gateway and the external user is only acknowledged if the computers involved authenticate each other via certificates and the external users authenticate via a multi-stage password system. All data are transferred encrypted. External users get only access to images that have been renamed to a pseudonym by means of automated processing before. With an ADSL internet access, external users achieve an image load frequency of 0.4 CT images per second. More than 90 % of the delay during image transfer results from security checks within the firewalls. Data passing the gateway induce no measurable delay. Project goals were realized by means of an infrastructure that works vendor independently with any HTML-based image distribution systems. The requirements of data security were realized using state-of-the-art web techniques. Adequate access and transfer speed lead to a widespread acceptance of the system on the part of external users.
DOT National Transportation Integrated Search
2012-03-01
In support of USDOTs Intelligent Transportation Systems (ITS) Mobility Program, the Dynamic Mobility Applications (DMA) program seeks to create applications that fully leverage frequently collected and rapidly disseminated multi-source data gat...
García-Soler, Álvaro; Facal, David; Díaz-Orueta, Unai; Pigini, Lucia; Blasi, Lorenzo; Qiu, Renxi
2018-01-01
The implications for the inclusion of robots in the daily lives of frail older adults, especially in relation to these population needs, have not been extensively studied. The "Multi-Role Shadow Robotic System for Independent Living" (SRS) project has developed a remotely-controlled, semi-autonomous robotic system to be used in domestic environments. The objective of this paper is to document the iterative procedure used to identify, select and prioritize user requirements. Seventy-four requirements were identified by means of focus groups, individual interviews and scenario-based interviews. The list of user requirements, ordered according to impact, number and transnational criteria, revealed a high number of requirements related to basic and instrumental activities of daily living, cognitive and social support and monitorization, and also involving privacy, safety and adaptation issues. Analysing and understanding older users' perceptions and needs when interacting with technological devices adds value to assistive technology and ensures that the systems address currently unmet needs. Copyright © 2017 Elsevier B.V. All rights reserved.
Multi-client quantum key distribution using wavelength division multiplexing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grice, Warren P; Bennink, Ryan S; Earl, Dennis Duncan
Quantum Key Distribution (QKD) exploits the rules of quantum mechanics to generate and securely distribute a random sequence of bits to two spatially separated clients. Typically a QKD system can support only a single pair of clients at a time, and so a separate quantum link is required for every pair of users. We overcome this limitation with the design and characterization of a multi-client entangled-photon QKD system with the capacity for up to 100 clients simultaneously. The time-bin entangled QKD system includes a broadband down-conversion source with two unique features that enable the multi-user capability. First, the photons aremore » emitted across a very large portion of the telecom spectrum. Second, and more importantly, the photons are strongly correlated in their energy degree of freedom. Using standard wavelength division multiplexing (WDM) hardware, the photons can be routed to different parties on a quantum communication network, while the strong spectral correlations ensure that each client is linked only to the client receiving the conjugate wavelength. In this way, a single down-conversion source can support dozens of channels simultaneously--and to the extent that the WDM hardware can send different spectral channels to different clients, the system can support multiple client pairings. We will describe the design and characterization of the down-conversion source, as well as the client stations, which must be tunable across the emission spectrum.« less
NASA Astrophysics Data System (ADS)
Yoon, J.; Klassert, C. J. A.; Lachaut, T.; Selby, P. D.; Knox, S.; Gorelick, S.; Rajsekhar, D.; Tilmant, A.; Avisse, N.; Harou, J. J.; Gawel, E.; Klauer, B.; Mustafa, D.; Talozi, S.; Sigel, K.
2015-12-01
Our work focuses on development of a multi-agent, hydroeconomic model for purposes of water policy evaluation in Jordan. The model adopts a modular approach, integrating biophysical modules that simulate natural and engineered phenomena with human modules that represent behavior at multiple levels of decision making. The hydrologic modules are developed using spatially-distributed groundwater and surface water models, which are translated into compact simulators for efficient integration into the multi-agent model. For the groundwater model, we adopt a response matrix method approach in which a 3-dimensional MODFLOW model of a complex regional groundwater system is converted into a linear simulator of groundwater response by pre-processing drawdown results from several hundred numerical simulation runs. Surface water models for each major surface water basin in the country are developed in SWAT and similarly translated into simple rainfall-runoff functions for integration with the multi-agent model. The approach balances physically-based, spatially-explicit representation of hydrologic systems with the efficiency required for integration into a complex multi-agent model that is computationally amenable to robust scenario analysis. For the multi-agent model, we explicitly represent human agency at multiple levels of decision making, with agents representing riparian, management, supplier, and water user groups. The agents' decision making models incorporate both rule-based heuristics as well as economic optimization. The model is programmed in Python using Pynsim, a generalizable, open-source object-oriented code framework for modeling network-based water resource systems. The Jordan model is one of the first applications of Pynsim to a real-world water management case study. Preliminary results from a tanker market scenario run through year 2050 are presented in which several salient features of the water system are investigated: competition between urban and private farmer agents, the emergence of a private tanker market, disparities in economic wellbeing to different user groups caused by unique supply conditions, and response of the complex system to various policy interventions.
Towards Simpler Custom and OpenSearch Services for Voluminous NEWS Merged A-Train Data (Invited)
NASA Astrophysics Data System (ADS)
Hua, H.; Fetzer, E.; Braverman, A. J.; Lewis, S.; Henderson, M. L.; Guillaume, A.; Lee, S.; de La Torre Juarez, M.; Dang, H. T.
2010-12-01
To simplify access to large and complex satellite data sets for climate analysis and model verification, we developed web services that is used to study long-term and global-scale trends in climate, water and energy cycle, and weather variability. A related NASA Energy and Water Cycle Study (NEWS) task has created a merged NEWS Level 2 data from multiple instruments in NASA’s A-Train constellation of satellites. We used this data to enable creation of climatologies that include correlation between observed temperature, water vapor and cloud properties from the A-Train sensors. Instead of imposing on the user an often rigid and limiting web-based analysis environment, we recognize the need for simple and well-designed services so that users can perform analysis in their own familiar computing environments. Custom on-demand services were developed to improve data accessibility of voluminous multi-sensor data. Services enabling geospatial, geographical, and multi-sensor parameter subsets of the data, as well a custom time-averaged Level 3 service will be presented. We will also show how a Level 3Q data reduction approach can be used to help “browse” the voluminous multi-sensor Level 2 data. An OpenSearch capability with full text + space + time search of data products will also be presented as an approach to facilitated interoperability with other data systems. We will present our experiences for improving user usability as well as strategies for facilitating interoperability with other data systems.
Determining the Impact of Personal Mobility Carbon Allowance Schemes in Transportation Networks
Aziz, H. M. Abdul; Ukkusuri, Satish V.; Zhan, Xianyuan
2016-10-17
We know that personal mobility carbon allowance (PMCA) schemes are designed to reduce carbon consumption from transportation networks. PMCA schemes influence the travel decision process of users and accordingly impact the system metrics including travel time and greenhouse gas (GHG) emissions. Here, we develop a multi-user class dynamic user equilibrium model to evaluate the transportation system performance when PMCA scheme is implemented. The results using Sioux-Falls test network indicate that PMCA schemes can achieve the emissions reduction goals for transportation networks. Further, users characterized by high value of travel time are found to be less sensitive to carbon budget inmore » the context of work trips. Results also show that PMCA scheme can lead to higher emissions for a path compared with the case without PMCA because of flow redistribution. The developed network equilibrium model allows us to examine the change in system states at different carbon allocation levels and to design parameters of PMCA schemes accounting for population heterogeneity.« less
Determining the Impact of Personal Mobility Carbon Allowance Schemes in Transportation Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aziz, H. M. Abdul; Ukkusuri, Satish V.; Zhan, Xianyuan
We know that personal mobility carbon allowance (PMCA) schemes are designed to reduce carbon consumption from transportation networks. PMCA schemes influence the travel decision process of users and accordingly impact the system metrics including travel time and greenhouse gas (GHG) emissions. Here, we develop a multi-user class dynamic user equilibrium model to evaluate the transportation system performance when PMCA scheme is implemented. The results using Sioux-Falls test network indicate that PMCA schemes can achieve the emissions reduction goals for transportation networks. Further, users characterized by high value of travel time are found to be less sensitive to carbon budget inmore » the context of work trips. Results also show that PMCA scheme can lead to higher emissions for a path compared with the case without PMCA because of flow redistribution. The developed network equilibrium model allows us to examine the change in system states at different carbon allocation levels and to design parameters of PMCA schemes accounting for population heterogeneity.« less
Multi-Mission Power Analysis Tool (MMPAT) Version 3
NASA Technical Reports Server (NTRS)
Wood, Eric G.; Chang, George W.; Chen, Fannie C.
2012-01-01
The Multi-Mission Power Analysis Tool (MMPAT) simulates a spacecraft power subsystem including the power source (solar array and/or radioisotope thermoelectric generator), bus-voltage control, secondary battery (lithium-ion or nickel-hydrogen), thermostatic heaters, and power-consuming equipment. It handles multiple mission types including heliocentric orbiters, planetary orbiters, and surface operations. Being parametrically driven along with its user-programmable features can reduce or even eliminate any need for software modifications when configuring it for a particular spacecraft. It provides multiple levels of fidelity, thereby fulfilling the vast majority of a project s power simulation needs throughout the lifecycle. It can operate in a stand-alone mode with a graphical user interface, in batch mode, or as a library linked with other tools. This software can simulate all major aspects of a spacecraft power subsystem. It is parametrically driven to reduce or eliminate the need for a programmer. Added flexibility is provided through user-designed state models and table-driven parameters. MMPAT is designed to be used by a variety of users, such as power subsystem engineers for sizing power subsystem components; mission planners for adjusting mission scenarios using power profiles generated by the model; system engineers for performing system- level trade studies using the results of the model during the early design phases of a spacecraft; and operations personnel for high-fidelity modeling of the essential power aspect of the planning picture.
Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement
2013-10-02
ISS037-E-004956 (2 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, performs the Multi-user Droplet Combustion Apparatus (MDCA) hardware replacement in the Harmony node of the International Space Station.
Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement
2013-10-02
ISS037-E-004959 (2 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, performs the Multi-user Droplet Combustion Apparatus (MDCA) hardware replacement in the Harmony node of the International Space Station.
Versatile clinical information system design for emergency departments.
Amouh, Teh; Gemo, Monica; Macq, Benoît; Vanderdonckt, Jean; El Gariani, Abdul Wahed; Reynaert, Marc S; Stamatakis, Lambert; Thys, Frédéric
2005-06-01
Compared to other hospital units, the emergency department presents some distinguishing characteristics of its own. Emergency health-care delivery is a collaborative process involving the contribution of several individuals who accomplish their tasks while working autonomously under pressure and sometimes with limited resources. Effective computerization of the emergency department information system presents a real challenge due to the complexity of the scenario. Current computerized support suffers from several problems, including inadequate data models, clumsy user interfaces, and poor integration with other clinical information systems. To tackle such complexity, we propose an approach combining three points of view, namely the transactions (in and out of the department), the (mono and multi) user interfaces and data management. Unlike current systems, we pay particular attention to the user-friendliness and versatility of our system. This means that intuitive user interfaces have been conceived and specific software modeling methodologies have been applied to provide our system with the flexibility and adaptability necessary for the individual and group coordinated tasks. Our approach has been implemented by prototyping a web-based, multiplatform, multiuser, and versatile clinical information system built upon multitier software architecture, using the Java programming language.
Computer-based route-definition system for peripheral bronchoscopy.
Graham, Michael W; Gibbs, Jason D; Higgins, William E
2012-04-01
Multi-detector computed tomography (MDCT) scanners produce high-resolution images of the chest. Given a patient's MDCT scan, a physician can use an image-guided intervention system to first plan and later perform bronchoscopy to diagnostic sites situated deep in the lung periphery. An accurate definition of complete routes through the airway tree leading to the diagnostic sites, however, is vital for avoiding navigation errors during image-guided bronchoscopy. We present a system for the robust definition of complete airway routes suitable for image-guided bronchoscopy. The system incorporates both automatic and semiautomatic MDCT analysis methods for this purpose. Using an intuitive graphical user interface, the user invokes automatic analysis on a patient's MDCT scan to produce a series of preliminary routes. Next, the user visually inspects each route and quickly corrects the observed route defects using the built-in semiautomatic methods. Application of the system to a human study for the planning and guidance of peripheral bronchoscopy demonstrates the efficacy of the system.
MeV+R: using MeV as a graphical user interface for Bioconductor applications in microarray analysis
Chu, Vu T; Gottardo, Raphael; Raftery, Adrian E; Bumgarner, Roger E; Yeung, Ka Yee
2008-01-01
We present MeV+R, an integration of the JAVA MultiExperiment Viewer program with Bioconductor packages. This integration of MultiExperiment Viewer and R is easily extensible to other R packages and provides users with point and click access to traditionally command line driven tools written in R. We demonstrate the ability to use MultiExperiment Viewer as a graphical user interface for Bioconductor applications in microarray data analysis by incorporating three Bioconductor packages, RAMA, BRIDGE and iterativeBMA. PMID:18652698
A Multi-User Remote Academic Laboratory System
ERIC Educational Resources Information Center
Barrios, Arquimedes; Panche, Stifen; Duque, Mauricio; Grisales, Victor H.; Prieto, Flavio; Villa, Jose L.; Chevrel, Philippe; Canu, Michael
2013-01-01
This article describes the development, implementation and preliminary operation assessment of Multiuser Network Architecture to integrate a number of Remote Academic Laboratories for educational purposes on automatic control. Through the Internet, real processes or physical experiments conducted at the control engineering laboratories of four…
NASA Astrophysics Data System (ADS)
Nelson, Brian C.
2007-02-01
This study examines the patterns of use and potential impact of individualized, reflective guidance in an educational Multi-User Virtual Environment (MUVE). A guidance system embedded within a MUVE-based scientific inquiry curriculum was implemented with a sample of middle school students in an exploratory study investigating (a) whether access to the guidance system was associated with improved learning, (b) whether students viewing more guidance messages saw greater improvement on content tests than those viewing less, and (c) whether there were any differences in guidance use among boys and girls. Initial experimental findings showed that basic access to individualized guidance used with a MUVE had no measurable impact on learning. However, post-hoc exploratory analyses indicated that increased use of the system among those with access to it was positively associated with content test score gains. In addition, differences were found in overall learning outcomes by gender and in patterns of guidance use by boys and girls, with girls outperforming boys across a spectrum of guidance system use. Based on these exploratory findings, the paper suggests design guidelines for the development of guidance systems embedded in MUVEs and outlines directions for further research.
Atmospheric lidar multi-user instrument system definition study
NASA Technical Reports Server (NTRS)
Greco, R. V. (Editor)
1980-01-01
A spaceborne lidar system for atmospheric studies was defined. The primary input was the Science Objectives Experiment Description and Evolutionary Flow Document. The first task of the study was to perform an experiment evolutionary analysis of the SEED. The second task was the system definition effort of the instrument system. The third task was the generation of a program plan for the hardware phase. The fourth task was the supporting studies which included a Shuttle deficiency analysis, a preliminary safety hazard analysis, the identification of long lead items, and development studies required. As a result of the study an evolutionary Lidar Multi-User Instrument System (MUIS) was defined. The MUIS occupies a full Spacelab pallet and has a weight of 1300 kg. The Lidar MUIS laser provides a 2 joule frequency doubled Nd:YAG laser that can also pump a tuneable dye laser wide frequency range and bandwidth. The MUIS includes a 1.25 meter diameter aperture Cassegrain receiver, with a moveable secondary mirror to provide precise alignment with the laser. The receiver can transmit the return signal to three single and multiple photomultiple tube detectors by use of a rotating fold mirror. It is concluded that the Lidar MUIS proceed to program implementation.
Implementing TCP/IP and a socket interface as a server in a message-passing operating system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hipp, E.; Wiltzius, D.
1990-03-01
The UNICOS 4.3BSD network code and socket transport interface are the basis of an explicit network server for NLTSS, a message passing operating system on the Cray YMP. A BSD socket user library provides access to the network server using an RPC mechanism. The advantages of this server methodology are its modularity and extensibility to migrate to future protocol suites (e.g. OSI) and transport interfaces. In addition, the network server is implemented in an explicit multi-tasking environment to take advantage of the Cray YMP multi-processor platform. 19 refs., 5 figs.
Scalable and Power Efficient Data Analytics for Hybrid Exascale Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choudhary, Alok; Samatova, Nagiza; Wu, Kesheng
This project developed a generic and optimized set of core data analytics functions. These functions organically consolidate a broad constellation of high performance analytical pipelines. As the architectures of emerging HPC systems become inherently heterogeneous, there is a need to design algorithms for data analysis kernels accelerated on hybrid multi-node, multi-core HPC architectures comprised of a mix of CPUs, GPUs, and SSDs. Furthermore, the power-aware trend drives the advances in our performance-energy tradeoff analysis framework which enables our data analysis kernels algorithms and software to be parameterized so that users can choose the right power-performance optimizations.
Oh, Chin Wan; Cao, Zizheng; Tangdiongga, Eduward; Koonen, Ton
2016-08-22
In order to circumvent radio spectrum congestion, we propose an innovative system which can provide multiple infrared optical wireless beams simultaneously where each beam supports multi-gigabit-per-second communication. Scalable two-dimensional beam steering by means of wavelength tuning is proposed. A passive beam-steering module constructed with cascaded reflection gratings is designed for simultaneous multi-user coverage. We experimentally characterized the beam-steered system and thoroughly evaluated the performance of steered channels using the spectrally efficient and robust discrete multitone modulation in a bandwidth-limited system deploying 10 GHz telecom transceivers. This study reports the achievement of at least 37 Gbps free-space transmission per beam over a distance of up to 2 m over 5.61° × 12.66° scanning angles.
A comparison of representations for discrete multi-criteria decision problems☆
Gettinger, Johannes; Kiesling, Elmar; Stummer, Christian; Vetschera, Rudolf
2013-01-01
Discrete multi-criteria decision problems with numerous Pareto-efficient solution candidates place a significant cognitive burden on the decision maker. An interactive, aspiration-based search process that iteratively progresses toward the most preferred solution can alleviate this task. In this paper, we study three ways of representing such problems in a DSS, and compare them in a laboratory experiment using subjective and objective measures of the decision process as well as solution quality and problem understanding. In addition to an immediate user evaluation, we performed a re-evaluation several weeks later. Furthermore, we consider several levels of problem complexity and user characteristics. Results indicate that different problem representations have a considerable influence on search behavior, although long-term consistency appears to remain unaffected. We also found interesting discrepancies between subjective evaluations and objective measures. Conclusions from our experiments can help designers of DSS for large multi-criteria decision problems to fit problem representations to the goals of their system and the specific task at hand. PMID:24882912
Method and system for providing work machine multi-functional user interface
Hoff, Brian D [Peoria, IL; Akasam, Sivaprasad [Peoria, IL; Baker, Thomas M [Peoria, IL
2007-07-10
A method is performed to provide a multi-functional user interface on a work machine for displaying suggested corrective action. The process includes receiving status information associated with the work machine and analyzing the status information to determine an abnormal condition. The process also includes displaying a warning message on the display device indicating the abnormal condition and determining one or more corrective actions to handle the abnormal condition. Further, the process includes determining an appropriate corrective action among the one or more corrective actions and displaying a recommendation message on the display device reflecting the appropriate corrective action. The process may also include displaying a list including the remaining one or more corrective actions on the display device to provide alternative actions to an operator.
Software Supports Distributed Operations via the Internet
NASA Technical Reports Server (NTRS)
Norris, Jeffrey; Backers, Paul; Steinke, Robert
2003-01-01
Multi-mission Encrypted Communication System (MECS) is a computer program that enables authorized, geographically dispersed users to gain secure access to a common set of data files via the Internet. MECS is compatible with legacy application programs and a variety of operating systems. The MECS architecture is centered around maintaining consistent replicas of data files cached on remote computers. MECS monitors these files and, whenever one is changed, the changed file is committed to a master database as soon as network connectivity makes it possible to do so. MECS provides subscriptions for remote users to automatically receive new data as they are generated. Remote users can be producers as well as consumers of data. Whereas a prior program that provides some of the same services treats disconnection of a user from the network of users as an error from which recovery must be effected, MECS treats disconnection as a nominal state of the network: This leads to a different design that is more efficient for serving many users, each of whom typically connects and disconnects frequently and wants only a small fraction of the data at any given time.
ERIC Educational Resources Information Center
Shee, Daniel Y.; Wang, Yi-Shun
2008-01-01
The web-based e-learning system (WELS) has emerged as a new means of skill training and knowledge acquisition, encouraging both academia and industry to invest resources in the adoption of this system. Traditionally, most pre- and post-adoption tasks related to evaluation are carried out from the viewpoints of technology. Since users have been…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Balducelli, C.; Bologna, S.; Di Costanzo, G.
1995-12-31
The paper describes part of the results achieved in the framework of the MUSTER project (Multi-Users System for Training and Evaluating Environmental Emergency Response). The aim of this project is to define the detailed specifications of a computer based system supporting collaborative training for emergency management. A system prototype has been implemented to support the refinement and improvement of the system specifications.
Center Planning and Development: Multi-User Spaceport Initiatives
NASA Technical Reports Server (NTRS)
Kennedy, Christopher John
2015-01-01
The Vehicle Assembly building at NASAs Kennedy Space Center has been used since 1966 to vertically assemble every launch vehicle, since the Apollo Program, launched from Launch Complex 39 (LC-39). After the cancellation of the Constellation Program in 2010 and the retirement of the Space Shuttle Program in 2011, the VAB faced an uncertain future. As the Space Launch System (SLS) gained a foothold as the future of American spaceflight to deep space, NASA was only using a portion of the VABs initial potential. With three high bays connected to the Crawler Way transportation system, the potential exists for up to three rockets to be simultaneously processed for launch. The Kennedy Space Center (KSC) Master plan, supported by the Center Planning and Development (CPD) Directorate, is guiding Kennedy toward a 21st century multi-user spaceport. This concept will maintain Kennedy as the United States premier gateway to space and provide multi-user operations through partnerships with the commercial aerospace industry. Commercial aerospace companies, now tasked with transporting cargo and, in the future, astronauts to the International Space Station (ISS) via the Commercial Resupply Service (CRS) and Commercial Crew Program (CCP), are a rapidly growing industry with increasing capabilities to make launch operations more economical for both private companies and the government. Commercial operations to Low Earth Orbit allow the government to focus on travel to farther destinations through the SLS Program. With LC-39B designated as a multi-use launch pad, companies seeking to use it will require an integration facility to assemble, integrate, and test their launch vehicle. An Announcement for Proposals (AFP) was released in June, beginning the process of finding a non-NASA user for High Bay 2 (HB2) and the Mobile Launcher Platforms (MLPs). An Industry Day, a business meeting and tour for interested companies and organizations, was also arranged to identify and answer any additional questions posed by potential proposers. After amending the AFP and posting additional material for potential users to consider, proposals are being accepted until July 31, at which point they will be evaluated to determine the proposer which best meets the objectives of the government. By identifying VAB HB2 as available and seeking proposals from the commercial sector for VAB HB2 and MLP use, Center Planning and Development is ensuring Kennedy Space Centers relevance in the evolving launch industry of the 21st century.
Xu, Qian; Tan, Chengxiang; Fan, Zhijie; Zhu, Wenye; Xiao, Ya; Cheng, Fujia
2018-05-17
Nowadays, fog computing provides computation, storage, and application services to end users in the Internet of Things. One of the major concerns in fog computing systems is how fine-grained access control can be imposed. As a logical combination of attribute-based encryption and attribute-based signature, Attribute-based Signcryption (ABSC) can provide confidentiality and anonymous authentication for sensitive data and is more efficient than traditional "encrypt-then-sign" or "sign-then-encrypt" strategy. Thus, ABSC is suitable for fine-grained access control in a semi-trusted cloud environment and is gaining more and more attention recently. However, in many existing ABSC systems, the computation cost required for the end users in signcryption and designcryption is linear with the complexity of signing and encryption access policy. Moreover, only a single authority that is responsible for attribute management and key generation exists in the previous proposed ABSC schemes, whereas in reality, mostly, different authorities monitor different attributes of the user. In this paper, we propose OMDAC-ABSC, a novel data access control scheme based on Ciphertext-Policy ABSC, to provide data confidentiality, fine-grained control, and anonymous authentication in a multi-authority fog computing system. The signcryption and designcryption overhead for the user is significantly reduced by outsourcing the undesirable computation operations to fog nodes. The proposed scheme is proven to be secure in the standard model and can provide attribute revocation and public verifiability. The security analysis, asymptotic complexity comparison, and implementation results indicate that our construction can balance the security goals with practical efficiency in computation.
NASA Astrophysics Data System (ADS)
McAllister, M.; Gochis, D.; Dugger, A. L.; Karsten, L. R.; McCreight, J. L.; Pan, L.; Rafieeinasab, A.; Read, L. K.; Sampson, K. M.; Yu, W.
2017-12-01
The community WRF-Hydro modeling system is publicly available and provides researchers and operational forecasters a flexible and extensible capability for performing multi-scale, multi-physics options for hydrologic modeling that can be run independent or fully-interactive with the WRF atmospheric model. The core WRF-Hydro physics model contains very high-resolution descriptions of terrestrial hydrologic process representations such as land-atmosphere exchanges of energy and moisture, snowpack evolution, infiltration, terrain routing, channel routing, basic reservoir representation and hydrologic data assimilation. Complementing the core physics components of WRF-Hydro are an ecosystem of pre- and post-processing tools that facilitate the preparation of terrain and meteorological input data, an open-source hydrologic model evaluation toolset (Rwrfhydro), hydrologic data assimilation capabilities with DART and advanced model visualization capabilities. The National Center for Atmospheric Research (NCAR), through collaborative support from the National Science Foundation and other funding partners, provides community support for the entire WRF-Hydro system through a variety of mechanisms. This presentation summarizes the enhanced user support capabilities that are being developed for the community WRF-Hydro modeling system. These products and services include a new website, open-source code repositories, documentation and user guides, test cases, online training materials, live, hands-on training sessions, an email list serve, and individual user support via email through a new help desk ticketing system. The WRF-Hydro modeling system and supporting tools which now include re-gridding scripts and model calibration have recently been updated to Version 4 and are merging toward capabilities of the National Water Model.
Design and Verification of Remote Sensing Image Data Center Storage Architecture Based on Hadoop
NASA Astrophysics Data System (ADS)
Tang, D.; Zhou, X.; Jing, Y.; Cong, W.; Li, C.
2018-04-01
The data center is a new concept of data processing and application proposed in recent years. It is a new method of processing technologies based on data, parallel computing, and compatibility with different hardware clusters. While optimizing the data storage management structure, it fully utilizes cluster resource computing nodes and improves the efficiency of data parallel application. This paper used mature Hadoop technology to build a large-scale distributed image management architecture for remote sensing imagery. Using MapReduce parallel processing technology, it called many computing nodes to process image storage blocks and pyramids in the background to improve the efficiency of image reading and application and sovled the need for concurrent multi-user high-speed access to remotely sensed data. It verified the rationality, reliability and superiority of the system design by testing the storage efficiency of different image data and multi-users and analyzing the distributed storage architecture to improve the application efficiency of remote sensing images through building an actual Hadoop service system.
Multi-Axis Force Sensor for Human-Robot Interaction Sensing in a Rehabilitation Robotic Device.
Grosu, Victor; Grosu, Svetlana; Vanderborght, Bram; Lefeber, Dirk; Rodriguez-Guerrero, Carlos
2017-06-05
Human-robot interaction sensing is a compulsory feature in modern robotic systems where direct contact or close collaboration is desired. Rehabilitation and assistive robotics are fields where interaction forces are required for both safety and increased control performance of the device with a more comfortable experience for the user. In order to provide an efficient interaction feedback between the user and rehabilitation device, high performance sensing units are demanded. This work introduces a novel design of a multi-axis force sensor dedicated for measuring pelvis interaction forces in a rehabilitation exoskeleton device. The sensor is conceived such that it has different sensitivity characteristics for the three axes of interest having also movable parts in order to allow free rotations and limit crosstalk errors. Integrated sensor electronics make it easy to acquire and process data for a real-time distributed system architecture. Two of the developed sensors are integrated and tested in a complex gait rehabilitation device for safe and compliant control.
Energy Efficiency of D2D Multi-User Cooperation.
Zhang, Zufan; Wang, Lu; Zhang, Jie
2017-03-28
The Device-to-Device (D2D) communication system is an important part of heterogeneous networks. It has great potential to improve spectrum efficiency, throughput and energy efficiency cooperation of multiple D2D users with the advantage of direct communication. When cooperating, D2D users expend extraordinary energy to relay data to other D2D users. Hence, the remaining energy of D2D users determines the life of the system. This paper proposes a cooperation scheme for multiple D2D users who reuse the orthogonal spectrum and are interested in the same data by aiming to solve the energy problem of D2D users. Considering both energy availability and the Signal to Noise Ratio (SNR) of each D2D user, the Kuhn-Munkres algorithm is introduced in the cooperation scheme to solve relay selection problems. Thus, the cooperation issue is transformed into a maximum weighted matching (MWM) problem. In order to enhance energy efficiency without the deterioration of Quality of Service (QoS), the link outage probability is derived according to the Shannon Equation by considering the data rate and delay. The simulation studies the relationships among the number of cooperative users, the length of shared data, the number of data packets and energy efficiency.
System of end-to-end symmetric database encryption
NASA Astrophysics Data System (ADS)
Galushka, V. V.; Aydinyan, A. R.; Tsvetkova, O. L.; Fathi, V. A.; Fathi, D. V.
2018-05-01
The article is devoted to the actual problem of protecting databases from information leakage, which is performed while bypassing access control mechanisms. To solve this problem, it is proposed to use end-to-end data encryption, implemented at the end nodes of an interaction of the information system components using one of the symmetric cryptographic algorithms. For this purpose, a key management method designed for use in a multi-user system based on the distributed key representation model, part of which is stored in the database, and the other part is obtained by converting the user's password, has been developed and described. In this case, the key is calculated immediately before the cryptographic transformations and is not stored in the memory after the completion of these transformations. Algorithms for registering and authorizing a user, as well as changing his password, have been described, and the methods for calculating parts of a key when performing these operations have been provided.
Skin condition measurement by using multispectral imaging system (Conference Presentation)
NASA Astrophysics Data System (ADS)
Jung, Geunho; Kim, Sungchul; Kim, Jae Gwan
2017-02-01
There are a number of commercially available low level light therapy (LLLT) devices in a market, and face whitening or wrinkle reduction is one of targets in LLLT. The facial improvement could be known simply by visual observation of face, but it cannot provide either quantitative data or recognize a subtle change. Clinical diagnostic instruments such as mexameter can provide a quantitative data, but it costs too high for home users. Therefore, we designed a low cost multi-spectral imaging device by adding additional LEDs (470nm, 640nm, white LED, 905nm) to a commercial USB microscope which has two LEDs (395nm, 940nm) as light sources. Among various LLLT skin treatments, we focused on getting melanin and wrinkle information. For melanin index measurements, multi-spectral images of nevus were acquired and melanin index values from color image (conventional method) and from multi-spectral images were compared. The results showed that multi-spectral analysis of melanin index can visualize nevus with a different depth and concentration. A cross section of wrinkle on skin resembles a wedge which can be a source of high frequency components when the skin image is Fourier transformed into a spatial frequency domain map. In that case, the entropy value of the spatial frequency map can represent the frequency distribution which is related with the amount and thickness of wrinkle. Entropy values from multi-spectral images can potentially separate the percentage of thin and shallow wrinkle from thick and deep wrinkle. From the results, we found that this low cost multi-spectral imaging system could be beneficial for home users of LLLT by providing the treatment efficacy in a quantitative way.
Enabling multi-level relevance feedback on PubMed by integrating rank learning into DBMS
2010-01-01
Background Finding relevant articles from PubMed is challenging because it is hard to express the user's specific intention in the given query interface, and a keyword query typically retrieves a large number of results. Researchers have applied machine learning techniques to find relevant articles by ranking the articles according to the learned relevance function. However, the process of learning and ranking is usually done offline without integrated with the keyword queries, and the users have to provide a large amount of training documents to get a reasonable learning accuracy. This paper proposes a novel multi-level relevance feedback system for PubMed, called RefMed, which supports both ad-hoc keyword queries and a multi-level relevance feedback in real time on PubMed. Results RefMed supports a multi-level relevance feedback by using the RankSVM as the learning method, and thus it achieves higher accuracy with less feedback. RefMed "tightly" integrates the RankSVM into RDBMS to support both keyword queries and the multi-level relevance feedback in real time; the tight coupling of the RankSVM and DBMS substantially improves the processing time. An efficient parameter selection method for the RankSVM is also proposed, which tunes the RankSVM parameter without performing validation. Thereby, RefMed achieves a high learning accuracy in real time without performing a validation process. RefMed is accessible at http://dm.postech.ac.kr/refmed. Conclusions RefMed is the first multi-level relevance feedback system for PubMed, which achieves a high accuracy with less feedback. It effectively learns an accurate relevance function from the user’s feedback and efficiently processes the function to return relevant articles in real time. PMID:20406504
Flat Surface Damage Detection System (FSDDS)
NASA Technical Reports Server (NTRS)
Williams, Martha; Lewis, Mark; Gibson, Tracy; Lane, John; Medelius, Pedro; Snyder, Sarah; Ciarlariello, Dan; Parks, Steve; Carrejo, Danny; Rojdev, Kristina
2013-01-01
The Flat Surface Damage Detection system (FSDDS} is a sensory system that is capable of detecting impact damages to surfaces utilizing a novel sensor system. This system will provide the ability to monitor the integrity of an inflatable habitat during in situ system health monitoring. The system consists of three main custom designed subsystems: the multi-layer sensing panel, the embedded monitoring system, and the graphical user interface (GUI). The GUI LABVIEW software uses a custom developed damage detection algorithm to determine the damage location based on the sequence of broken sensing lines. It estimates the damage size, the maximum depth, and plots the damage location on a graph. Successfully demonstrated as a stand alone technology during 2011 D-RATS. Software modification also allowed for communication with HDU avionics crew display which was demonstrated remotely (KSC to JSC} during 2012 integration testing. Integrated FSDDS system and stand alone multi-panel systems were demonstrated remotely and at JSC, Mission Operations Test using Space Network Research Federation (SNRF} network in 2012. FY13, FSDDS multi-panel integration with JSC and SNRF network Technology can allow for integration with other complementary damage detection systems.
Toward visual user interfaces supporting collaborative multimedia content management
NASA Astrophysics Data System (ADS)
Husein, Fathi; Leissler, Martin; Hemmje, Matthias
2000-12-01
Supporting collaborative multimedia content management activities, as e.g., image and video acquisition, exploration, and access dialogues between naive users and multi media information systems is a non-trivial task. Although a wide variety of experimental and prototypical multimedia storage technologies as well as corresponding indexing and retrieval engines are available, most of them lack appropriate support for collaborative end-user oriented user interface front ends. The development of advanced user adaptable interfaces is necessary for building collaborative multimedia information- space presentations based upon advanced tools for information browsing, searching, filtering, and brokering to be applied on potentially very large and highly dynamic multimedia collections with a large number of users and user groups. Therefore, the development of advanced and at the same time adaptable and collaborative computer graphical information presentation schemes that allow to easily apply adequate visual metaphors for defined target user stereotypes has to become a key focus within ongoing research activities trying to support collaborative information work with multimedia collections.
Development of multi-mission satellite data systems at the German Remote Sensing Data Centre
NASA Astrophysics Data System (ADS)
Lotz-Iwen, H. J.; Markwitz, W.; Schreier, G.
1998-11-01
This paper focuses on conceptual aspects of the access to multi-mission remote sensing data by online catalogue and information systems. The system ISIS of the German Remote Sensing Data Centre is described as an example of a user interface to earth observation data. ISIS has been designed to support international scientific research as well as operational applications by offering online access to the database via public networks. It provides catalogue retrieval, visualisation and transfer of image data, and is integrated in international activities dedicated to catalogue and archive interoperability. Finally, an outlook is given on international projects dealing with access to remote sensing data in distributed archives.
NASA Astrophysics Data System (ADS)
Odijk, Dennis; Zhang, Baocheng; Khodabandeh, Amir; Odolinski, Robert; Teunissen, Peter J. G.
2016-01-01
The concept of integer ambiguity resolution-enabled Precise Point Positioning (PPP-RTK) relies on appropriate network information for the parameters that are common between the single-receiver user that applies and the network that provides this information. Most of the current methods for PPP-RTK are based on forming the ionosphere-free combination using dual-frequency Global Navigation Satellite System (GNSS) observations. These methods are therefore restrictive in the light of the development of new multi-frequency GNSS constellations, as well as from the point of view that the PPP-RTK user requires ionospheric corrections to obtain integer ambiguity resolution results based on short observation time spans. The method for PPP-RTK that is presented in this article does not have above limitations as it is based on the undifferenced, uncombined GNSS observation equations, thereby keeping all parameters in the model. Working with the undifferenced observation equations implies that the models are rank-deficient; not all parameters are unbiasedly estimable, but only combinations of them. By application of S-system theory the model is made of full rank by constraining a minimum set of parameters, or S-basis. The choice of this S-basis determines the estimability and the interpretation of the parameters that are transmitted to the PPP-RTK users. As this choice is not unique, one has to be very careful when comparing network solutions in different S-systems; in that case the S-transformation, which is provided by the S-system method, should be used to make the comparison. Knowing the estimability and interpretation of the parameters estimated by the network is shown to be crucial for a correct interpretation of the estimable PPP-RTK user parameters, among others the essential ambiguity parameters, which have the integer property which is clearly following from the interpretation of satellite phase biases from the network. The flexibility of the S-system method is furthermore demonstrated by the fact that all models in this article are derived in multi-epoch mode, allowing to incorporate dynamic model constraints on all or subsets of parameters.
Scalable Integrated Multi-Mission Support System Simulator Release 3.0
NASA Technical Reports Server (NTRS)
Kim, John; Velamuri, Sarma; Casey, Taylor; Bemann, Travis
2012-01-01
The Scalable Integrated Multi-mission Support System (SIMSS) is a tool that performs a variety of test activities related to spacecraft simulations and ground segment checks. SIMSS is a distributed, component-based, plug-and-play client-server system useful for performing real-time monitoring and communications testing. SIMSS runs on one or more workstations and is designed to be user-configurable or to use predefined configurations for routine operations. SIMSS consists of more than 100 modules that can be configured to create, receive, process, and/or transmit data. The SIMSS/GMSEC innovation is intended to provide missions with a low-cost solution for implementing their ground systems, as well as significantly reducing a mission s integration time and risk.
Persistent Topology and Metastable State in Conformational Dynamics
Chang, Huang-Wei; Bacallado, Sergio; Pande, Vijay S.; Carlsson, Gunnar E.
2013-01-01
The large amount of molecular dynamics simulation data produced by modern computational models brings big opportunities and challenges to researchers. Clustering algorithms play an important role in understanding biomolecular kinetics from the simulation data, especially under the Markov state model framework. However, the ruggedness of the free energy landscape in a biomolecular system makes common clustering algorithms very sensitive to perturbations of the data. Here, we introduce a data-exploratory tool which provides an overview of the clustering structure under different parameters. The proposed Multi-Persistent Clustering analysis combines insights from recent studies on the dynamics of systems with dominant metastable states with the concept of multi-dimensional persistence in computational topology. We propose to explore the clustering structure of the data based on its persistence on scale and density. The analysis provides a systematic way to discover clusters that are robust to perturbations of the data. The dominant states of the system can be chosen with confidence. For the clusters on the borderline, the user can choose to do more simulation or make a decision based on their structural characteristics. Furthermore, our multi-resolution analysis gives users information about the relative potential of the clusters and their hierarchical relationship. The effectiveness of the proposed method is illustrated in three biomolecules: alanine dipeptide, Villin headpiece, and the FiP35 WW domain. PMID:23565139
1991-09-01
iv III. THE ANALYTIC HIERARCHY PROCESS ..... ........ 15 A. INTRODUCTION ...... ................. 15 B. THE AHP PROCESS ...... ................ 16 C...INTRODUCTION ...... ................. 26 B. IMPLEMENTATION OF CERTS USING AHP ........ .. 27 1. Consistency ...... ................ 29 2. User Interface...the proposed technique into a Decision Support System. Expert Choice implements the Analytic Hierarchy Process ( AHP ), an approach to multi- criteria
TENTACLE Multi-Camera Immersive Surveillance System Phase 2
2015-04-16
successful in solving the most challenging video analytics problems and taking the advanced research concepts into working systems for end- users in both...commercial, space and military applications. Notable successes include winning the DARPA Urban Challenge , software autonomy to guide the NASA robots (spirit... challenging urban environments. CMU is developing a scalable and extensible architecture, improving search/pursuit/tracking capabilities, and addressing
Interactive orbital proximity operations planning system instruction and training guide
NASA Technical Reports Server (NTRS)
Grunwald, Arthur J.; Ellis, Stephen R.
1994-01-01
This guide instructs users in the operation of a Proximity Operations Planning System. This system uses an interactive graphical method for planning fuel-efficient rendezvous trajectories in the multi-spacecraft environment of the space station and allows the operator to compose a multi-burn transfer trajectory between orbit initial chaser and target trajectories. The available task time (window) of the mission is predetermined and the maneuver is subject to various operational constraints, such as departure, arrival, spatial, plume impingement, and en route passage constraints. The maneuvers are described in terms of the relative motion experienced in a space station centered coordinate system. Both in-orbital plane as well as out-of-orbital plane maneuvering is considered. A number of visual optimization aids are used for assisting the operator in reaching fuel-efficient solutions. These optimization aids are based on the Primer Vector theory. The visual feedback of trajectory shapes, operational constraints, and optimization functions, provided by user-transparent and continuously active background computations, allows the operator to make fast, iterative design changes that rapidly converge to fuel-efficient solutions. The planning tool is an example of operator-assisted optimization of nonlinear cost functions.
Situation exploration in a persistent surveillance system with multidimensional data
NASA Astrophysics Data System (ADS)
Habibi, Mohammad S.
2013-03-01
There is an emerging need for fusing hard and soft sensor data in an efficient surveillance system to provide accurate estimation of situation awareness. These mostly abstract, multi-dimensional and multi-sensor data pose a great challenge to the user in performing analysis of multi-threaded events efficiently and cohesively. To address this concern an interactive Visual Analytics (VA) application is developed for rapid assessment and evaluation of different hypotheses based on context-sensitive ontology spawn from taxonomies describing human/human and human/vehicle/object interactions. A methodology is described here for generating relevant ontology in a Persistent Surveillance System (PSS) and demonstrates how they can be utilized in the context of PSS to track and identify group activities pertaining to potential threats. The proposed VA system allows for visual analysis of raw data as well as metadata that have spatiotemporal representation and content-based implications. Additionally in this paper, a technique for rapid search of tagged information contingent to ranking and confidence is explained for analysis of multi-dimensional data. Lastly the issue of uncertainty associated with processing and interpretation of heterogeneous data is also addressed.
Perceptions and Use of Technology to Support Older Adults with Multimorbidity.
Murphy, Emma; Doyle, Julie; Hannigan, Caoimhe; Smith, Suzanne; Kuiper, Janneke; Jacobs, An; Hoogerwerf, Evert-Jan; Desideri, Lorenzo; Fiordelmondo, Valentina; Maluccelli, Lorenza; Brady, Anne-Marie; Dinsmore, John
2017-01-01
Digital technologies hold great potential to improve and advance home based integrated care for older people living with multiple chronic health conditions. In this paper, we present the results of a user requirement study for a planned digital integrated care system, based on the experiences and needs of key stakeholders. We present rich, multi-stakeholder, qualitative data on the perceptions and use of technology among older people with multiple chronic health conditions and their key support actors. We have outlined our future work for the design of the system, which will involve continuous stakeholder engagement through a user-centred co-design method.
DOT National Transportation Integrated Search
2007-10-12
This memorandum provides a preliminary feasibility assessment for a bicycle or combined bicycle/pedestrian (i.e., multi-user) facility at Appomattox Court House National Historical Park (NHP). This assessment is based on discussions with park staff, ...
2008-12-06
ISS018-E-010645 (6 Dec. 2008) --- Astronaut Michael Fincke, Expedition 18 commander, works on the Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA) in the Harmony node of the International Space Station.
Learning from Multiple Collaborating Intelligent Tutors: An Agent-based Approach.
ERIC Educational Resources Information Center
Solomos, Konstantinos; Avouris, Nikolaos
1999-01-01
Describes an open distributed multi-agent tutoring system (MATS) and discusses issues related to learning in such open environments. Topics include modeling a one student-many teachers approach in a computer-based learning context; distributed artificial intelligence; implementation issues; collaboration; and user interaction. (Author/LRW)
77 FR 53830 - Retirement of FASTforward
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-04
... States Postal Service, Domestic Mail Manual (DMM[supreg]) 602.5.0 to terminate the use of FASTforward...-address system, was developed in 1996 to enable Multi-Line Optical Character Reader (MLOCR) users a means... the following changes to Mailing Standards of the United States Postal Service, Domestic Mail Manual...
A Multi-Temporal Context-Aware System for Competences Management
ERIC Educational Resources Information Center
Rosa, João H.; Barbosa, Jorge L.; Kich, Marcos; Brito, Lucas
2015-01-01
The evolution of computing technology and wireless networks has contributed to the miniaturization of mobile devices and their increase in power, providing services anywhere and anytime. In this scenario, applications have considered the user's contexts to make decisions (Context Awareness). Context-aware applications have enabled new…
Moving from Batch to Field Using the RT3D Reactive Transport Modeling System
NASA Astrophysics Data System (ADS)
Clement, T. P.; Gautam, T. R.
2002-12-01
The public domain reactive transport code RT3D (Clement, 1997) is a general-purpose numerical code for solving coupled, multi-species reactive transport in saturated groundwater systems. The code uses MODFLOW to simulate flow and several modules of MT3DMS to simulate the advection and dispersion processes. RT3D employs the operator-split strategy which allows the code solve the coupled reactive transport problem in a modular fashion. The coupling between reaction and transport is defined through a separate module where the reaction equations are specified. The code supports a versatile user-defined reaction option that allows users to define their own reaction system through a Fortran-90 subroutine, known as the RT3D-reaction package. Further a utility code, known as BATCHRXN, allows the users to independently test and debug their reaction package. To analyze a new reaction system at a batch scale, users should first run BATCHRXN to test the ability of their reaction package to model the batch data. After testing, the reaction package can simply be ported to the RT3D environment to study the model response under 1-, 2-, or 3-dimensional transport conditions. This paper presents example problems that demonstrate the methods for moving from batch to field-scale simulations using BATCHRXN and RT3D codes. The first example describes a simple first-order reaction system for simulating the sequential degradation of Tetrachloroethene (PCE) and its daughter products. The second example uses a relatively complex reaction system for describing the multiple degradation pathways of Tetrachloroethane (PCA) and its daughter products. References 1) Clement, T.P, RT3D - A modular computer code for simulating reactive multi-species transport in 3-Dimensional groundwater aquifers, Battelle Pacific Northwest National Laboratory Research Report, PNNL-SA-28967, September, 1997. Available at: http://bioprocess.pnl.gov/rt3d.htm.
Brown, Benjamin; Balatsoukas, Panos; Williams, Richard; Sperrin, Matthew; Buchan, Iain
2018-01-01
Electronic audit and feedback (e-A&F) systems are used worldwide for care quality improvement. They measure health professionals' performance against clinical guidelines, and some systems suggest improvement actions. However, little is known about optimal interface designs for e-A&F, in particular how to present suggested actions for improvement. We developed a novel theory-informed system for primary care (the Performance Improvement plaN GeneratoR; PINGR) that covers the four principal interface components: clinical performance summaries; patient lists; detailed patient-level information; and suggested actions. As far as we are aware, this is the first report of an e-A&F system with all four interface components. (1) Use a combination of quantitative and qualitative methods to evaluate the usability of PINGR with target end-users; (2) refine existing design recommendations for e-A&F systems; (3) determine the implications of these recommendations for patient safety. We recruited seven primary care physicians to perform seven tasks with PINGR, during which we measured on-screen behaviour and eye movements. Participants subsequently completed usability questionnaires, and were interviewed in-depth. Data were integrated to: gain a more complete understanding of usability issues; enhance and explain each other's findings; and triangulate results to increase validity. Participants committed a median of 10 errors (range 8-21) when using PINGR's interface, and completed a median of five out of seven tasks (range 4-7). Errors violated six usability heuristics: clear response options; perceptual grouping and data relationships; representational formats; unambiguous description; visually distinct screens for confusable items; and workflow integration. Eye movement analysis revealed the integration of components largely supported effective user workflow, although the modular design of clinical performance summaries unnecessarily increased cognitive load. Interviews and questionnaires revealed PINGR is user-friendly, and that improved information prioritisation could further promote useful user action. Comparing our results with the wider usability literature we refine a previously published set of interface design recommendations for e-A&F. The implications for patient safety are significant regarding: user engagement; actionability; and information prioritisation. Our results also support adopting multi-method approaches in usability studies to maximise issue discovery and the credibility of findings. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Synthetic environment employing a craft for providing user perspective reference
Maples, Creve; Peterson, Craig A.
1997-10-21
A multi-dimensional user oriented synthetic environment system allows application programs to be programmed and accessed with input/output device independent, generic functional commands which are a distillation of the actual functions performed by any application program. A shared memory structure allows the translation of device specific commands to device independent, generic functional commands. Complete flexibility of the mapping of synthetic environment data to the user is thereby allowed. Accordingly, synthetic environment data may be provided to the user on parallel user information processing channels allowing the subcognitive mind to act as a filter, eliminating irrelevant information and allowing the processing of increase amounts of data by the user. The user is further provided with a craft surrounding the user within the synthetic environment, which craft, imparts important visual referential an motion parallax cues, enabling the user to better appreciate distances and directions within the synthetic environment. Display of this craft in close proximity to the user's point of perspective may be accomplished without substantially degrading the image resolution of the displayed portions of the synthetic environment.
Agreement Technologies for Energy Optimization at Home
2018-01-01
Nowadays, it is becoming increasingly common to deploy sensors in public buildings or homes with the aim of obtaining data from the environment and taking decisions that help to save energy. Many of the current state-of-the-art systems make decisions considering solely the environmental factors that cause the consumption of energy. These systems are successful at optimizing energy consumption; however, they do not adapt to the preferences of users and their comfort. Any system that is to be used by end-users should consider factors that affect their wellbeing. Thus, this article proposes an energy-saving system, which apart from considering the environmental conditions also adapts to the preferences of inhabitants. The architecture is based on a Multi-Agent System (MAS), its agents use Agreement Technologies (AT) to perform a negotiation process between the comfort preferences of the users and the degree of optimization that the system can achieve according to these preferences. A case study was conducted in an office building, showing that the proposed system achieved average energy savings of 17.15%. PMID:29783768
A User''s Guide to the Zwikker-Kosten Transmission Line Code (ZKTL)
NASA Technical Reports Server (NTRS)
Kelly, J. J.; Abu-Khajeel, H.
1997-01-01
This user's guide documents updates to the Zwikker-Kosten Transmission Line Code (ZKTL). This code was developed for analyzing new liner concepts developed to provide increased sound absorption. Contiguous arrays of multi-degree-of-freedom (MDOF) liner elements serve as the model for these liner configurations, and Zwikker and Kosten's theory of sound propagation in channels is used to predict the surface impedance. Transmission matrices for the various liner elements incorporate both analytical and semi-empirical methods. This allows standard matrix techniques to be employed in the code to systematically calculate the composite impedance due to the individual liner elements. The ZKTL code consists of four independent subroutines: 1. Single channel impedance calculation - linear version (SCIC) 2. Single channel impedance calculation - nonlinear version (SCICNL) 3. Multi-channel, multi-segment, multi-layer impedance calculation - linear version (MCMSML) 4. Multi-channel, multi-segment, multi-layer impedance calculation - nonlinear version (MCMSMLNL) Detailed examples, comments, and explanations for each liner impedance computation module are included. Also contained in the guide are depictions of the interactive execution, input files and output files.
ERIC Educational Resources Information Center
Vergo, John; Karat, Clare-Marie; Karat, John; Pinhanez, Claudio; Arora, Renee; Cofino, Thomas; Riecken, Doug; Podlaseck, Mark
This paper summarizes a 10-month long research project conducted at the IBM T.J. Watson Research Center aimed at developing the design concept of a multi-institutional art and culture web site. The work followed a user-centered design (UCD) approach, where interaction with prototypes and feedback from potential users of the web site were sought…
Public Auditing with Privacy Protection in a Multi-User Model of Cloud-Assisted Body Sensor Networks
Li, Song; Cui, Jie; Zhong, Hong; Liu, Lu
2017-01-01
Wireless Body Sensor Networks (WBSNs) are gaining importance in the era of the Internet of Things (IoT). The modern medical system is a particular area where the WBSN techniques are being increasingly adopted for various fundamental operations. Despite such increasing deployments of WBSNs, issues such as the infancy in the size, capabilities and limited data processing capacities of the sensor devices restrain their adoption in resource-demanding applications. Though providing computing and storage supplements from cloud servers can potentially enrich the capabilities of the WBSNs devices, data security is one of the prevailing issues that affects the reliability of cloud-assisted services. Sensitive applications such as modern medical systems demand assurance of the privacy of the users’ medical records stored in distant cloud servers. Since it is economically impossible to set up private cloud servers for every client, auditing data security managed in the remote servers has necessarily become an integral requirement of WBSNs’ applications relying on public cloud servers. To this end, this paper proposes a novel certificateless public auditing scheme with integrated privacy protection. The multi-user model in our scheme supports groups of users to store and share data, thus exhibiting the potential for WBSNs’ deployments within community environments. Furthermore, our scheme enriches user experiences by offering public verifiability, forward security mechanisms and revocation of illegal group members. Experimental evaluations demonstrate the security effectiveness of our proposed scheme under the Random Oracle Model (ROM) by outperforming existing cloud-assisted WBSN models. PMID:28475110
NASA Technical Reports Server (NTRS)
Santiago-Espada, Yamira; Myer, Robert R.; Latorella, Kara A.; Comstock, James R., Jr.
2011-01-01
The Multi-Attribute Task Battery (MAT Battery). is a computer-based task designed to evaluate operator performance and workload, has been redeveloped to operate in Windows XP Service Pack 3, Windows Vista and Windows 7 operating systems.MATB-II includes essentially the same tasks as the original MAT Battery, plus new configuration options including a graphical user interface for controlling modes of operation. MATB-II can be executed either in training or testing mode, as defined by the MATB-II configuration file. The configuration file also allows set up of the default timeouts for the tasks, the flow rates of the pumps and tank levels of the Resource Management (RESMAN) task. MATB-II comes with a default event file that an experimenter can modify and adapt
Effective Multi-Query Expansions: Collaborative Deep Networks for Robust Landmark Retrieval.
Wang, Yang; Lin, Xuemin; Wu, Lin; Zhang, Wenjie
2017-03-01
Given a query photo issued by a user (q-user), the landmark retrieval is to return a set of photos with their landmarks similar to those of the query, while the existing studies on the landmark retrieval focus on exploiting geometries of landmarks for similarity matches between candidate photos and a query photo. We observe that the same landmarks provided by different users over social media community may convey different geometry information depending on the viewpoints and/or angles, and may, subsequently, yield very different results. In fact, dealing with the landmarks with low quality shapes caused by the photography of q-users is often nontrivial and has seldom been studied. In this paper, we propose a novel framework, namely, multi-query expansions, to retrieve semantically robust landmarks by two steps. First, we identify the top- k photos regarding the latent topics of a query landmark to construct multi-query set so as to remedy its possible low quality shape. For this purpose, we significantly extend the techniques of Latent Dirichlet Allocation. Then, motivated by the typical collaborative filtering methods, we propose to learn a collaborative deep networks-based semantically, nonlinear, and high-level features over the latent factor for landmark photo as the training set, which is formed by matrix factorization over collaborative user-photo matrix regarding the multi-query set. The learned deep network is further applied to generate the features for all the other photos, meanwhile resulting into a compact multi-query set within such space. Then, the final ranking scores are calculated over the high-level feature space between the multi-query set and all other photos, which are ranked to serve as the final ranking list of landmark retrieval. Extensive experiments are conducted on real-world social media data with both landmark photos together with their user information to show the superior performance over the existing methods, especially our recently proposed multi-query based mid-level pattern representation method [1].
Remote voice training: A case study on space shuttle applications, appendix C
NASA Technical Reports Server (NTRS)
Mollakarimi, Cindy; Hamid, Tamin
1990-01-01
The Tile Automation System includes applications of automation and robotics technology to all aspects of the Shuttle tile processing and inspection system. An integrated set of rapid prototyping testbeds was developed which include speech recognition and synthesis, laser imaging systems, distributed Ada programming environments, distributed relational data base architectures, distributed computer network architectures, multi-media workbenches, and human factors considerations. Remote voice training in the Tile Automation System is discussed. The user is prompted over a headset by synthesized speech for the training sequences. The voice recognition units and the voice output units are remote from the user and are connected by Ethernet to the main computer system. A supervisory channel is used to monitor the training sequences. Discussions include the training approaches as well as the human factors problems and solutions for this system utilizing remote training techniques.
Design for interaction between humans and intelligent systems during real-time fault management
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Schreckenghost, Debra L.; Thronesbery, Carroll G.
1992-01-01
Initial results are reported to provide guidance and assistance for designers of intelligent systems and their human interfaces. The objective is to achieve more effective human-computer interaction (HCI) for real time fault management support systems. Studies of the development of intelligent fault management systems within NASA have resulted in a new perspective of the user. If the user is viewed as one of the subsystems in a heterogeneous, distributed system, system design becomes the design of a flexible architecture for accomplishing system tasks with both human and computer agents. HCI requirements and design should be distinguished from user interface (displays and controls) requirements and design. Effective HCI design for multi-agent systems requires explicit identification of activities and information that support coordination and communication between agents. The effects are characterized of HCI design on overall system design and approaches are identified to addressing HCI requirements in system design. The results include definition of (1) guidance based on information level requirements analysis of HCI, (2) high level requirements for a design methodology that integrates the HCI perspective into system design, and (3) requirements for embedding HCI design tools into intelligent system development environments.
Navigation Performance of Global Navigation Satellite Systems in the Space Service Volume
NASA Technical Reports Server (NTRS)
Force, Dale A.
2013-01-01
This paper extends the results I reported at this year's ION International Technical Meeting on multi-constellation GNSS coverage by showing how the use of multi-constellation GNSS improves Geometric Dilution of Precision (GDOP). Originally developed to provide position, navigation, and timing for terrestrial users, GPS has found increasing use for in space for precision orbit determination, precise time synchronization, real-time spacecraft navigation, and three-axis attitude control of Earth orbiting satellites. With additional Global Navigation Satellite Systems (GNSS) coming into service (GLONASS, Galileo, and Beidou) and the development of Satellite Based Augmentation Services, it is possible to obtain improved precision by using evolving multi-constellation receiver. The Space Service Volume formally defined as the volume of space between three thousand kilometers altitude and geosynchronous altitude ((is) approximately 36,500 km), with the volume below three thousand kilometers defined as the Terrestrial Service Volume (TSV). The USA has established signal requirements for the Space Service Volume (SSV) as part of the GPS Capability Development Documentation (CDD). Diplomatic efforts are underway to extend Space service Volume commitments to the other Position, Navigation, and Timing (PNT) service providers in an effort to assure that all space users will benefit from the enhanced capabilities of interoperating GNSS services in the space domain.
Xu, Jie; Le, Kim; Deitermann, Annika; Montague, Enid
2014-01-01
The aim of this study was to investigate the antecedents of trust in technology for active users and passive users working with a shared technology. According to the prominence-interpretation theory, to assess the trustworthiness of a technology, a person must first perceive and evaluate elements of the system that includes the technology. An experimental study was conducted with 54 participants who worked in two-person teams in a multi-task environment with a shared technology. Trust in technology was measured using a trust in technology questionnaire and antecedents of trust were elicited using an open-ended question. A list of antecedents of trust in technology was derived using qualitative analysis techniques. The following categories emerged from the antecedent: technology factors, user factors, and task factors. Similarities and differences between active users and passive user responses, in terms of trust in technology were discussed. PMID:24882059
Xu, Jie; Le, Kim; Deitermann, Annika; Montague, Enid
2014-11-01
The aim of this study was to investigate the antecedents of trust in technology for active users and passive users working with a shared technology. According to the prominence-interpretation theory, to assess the trustworthiness of a technology, a person must first perceive and evaluate elements of the system that includes the technology. An experimental study was conducted with 54 participants who worked in two-person teams in a multi-task environment with a shared technology. Trust in technology was measured using a trust in technology questionnaire and antecedents of trust were elicited using an open-ended question. A list of antecedents of trust in technology was derived using qualitative analysis techniques. The following categories emerged from the antecedent: technology factors, user factors, and task factors. Similarities and differences between active users and passive user responses, in terms of trust in technology were discussed. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.
An Intelligent Tutoring System (ITS) for Operating Training of ROCSAT TT&C Groung Station
NASA Astrophysics Data System (ADS)
Shr, Arthur M. D.; Miau, Jiun Jih
2000-07-01
ROCS AT-1 is the first small satellite developed by the Republic of China and is a lowearth orbit experimental satellite. The goal of ROCSAT-1 is to carry out scientific research missions. To successfully accomplish ROCSAT missions, the ROCSAT Mission Operations Team (RMOT) is formed to handle the daily operation and maintenance activities. These activities are onerous and complex. Hence, RMOT is concerned with future personnel training. In this paper, we propose an Intelligent Tutoring System (ITS) which is capable of integrating the training courses into a software program. ITS uses a great amount of information to present a subject for a user to learn. In the process of teaching, an ITS is capable of presenting the course materials in a structured format to the user and to judge if the user has mastered the subject or not. ITS is the tool to integrate the RMOT training courses and to develop a multi-function computer-assisted instruction (CAI) system. It can not only provide a practical method for users recurrently, but also make self-teaching easily.
Software Integration in Multi-scale Simulations: the PUPIL System
NASA Astrophysics Data System (ADS)
Torras, J.; Deumens, E.; Trickey, S. B.
2006-10-01
The state of the art for computational tools in both computational chemistry and computational materials physics includes many algorithms and functionalities which are implemented again and again. Several projects aim to reduce, eliminate, or avoid this problem. Most such efforts seem to be focused within a particular specialty, either quantum chemistry or materials physics. Multi-scale simulations, by their very nature however, cannot respect that specialization. In simulation of fracture, for example, the energy gradients that drive the molecular dynamics (MD) come from a quantum mechanical treatment that most often derives from quantum chemistry. That “QM” region is linked to a surrounding “CM” region in which potentials yield the forces. The approach therefore requires the integration or at least inter-operation of quantum chemistry and materials physics algorithms. The same problem occurs in “QM/MM” simulations in computational biology. The challenge grows if pattern recognition or other analysis codes of some kind must be used as well. The most common mode of inter-operation is user intervention: codes are modified as needed and data files are managed “by hand” by the user (interactively and via shell scripts). User intervention is however inefficient by nature, difficult to transfer to the community, and prone to error. Some progress (e.g Sethna’s work at Cornell [C.R. Myers et al., Mat. Res. Soc. Symp. Proc., 538(1999) 509, C.-S. Chen et al., Poster presented at the Material Research Society Meeting (2000)]) has been made on using Python scripts to achieve a more efficient level of interoperation. In this communication we present an alternative approach to merging current working packages without the necessity of major recoding and with only a relatively light wrapper interface. The scheme supports communication among the different components required for a given multi-scale calculation and access to the functionalities of those components for the potential user. A general main program allows the management of every package with a special communication protocol between their interfaces following the directives introduced by the user which are stored in an XML structured file. The initial prototype of the PUPIL (Program for User Packages Interfacing and Linking) system has been done using Java as a fast, easy prototyping object oriented (OO) language. In order to test it, we have applied this prototype to a previously studied problem, the fracture of a silica nanorod. We did so joining two different packages to do a QM/MD calculation. The results show the potential for this software system to do different kind of simulations and its simplicity of maintenance.
Teaching the Repeated Prisoner's Dilemma with a Computerized Tournament
ERIC Educational Resources Information Center
Lange, Carsten; Baylor, Amy L.
2007-01-01
The authors present a constructivist approach for teaching game theory, on the basis, in part, of Axelrod's research approach. Using the Axelrod tournament multi-user system (ATMUS) software, students create strategies for a repeated prisoner's dilemma (RPD). Later, these strategies are matched with those of their classmates' in a classroom…
Linking Multiple Databases: Term Project Using "Sentences" DBMS.
ERIC Educational Resources Information Center
King, Ronald S.; Rainwater, Stephen B.
This paper describes a methodology for use in teaching an introductory Database Management System (DBMS) course. Students master basic database concepts through the use of a multiple component project implemented in both relational and associative data models. The associative data model is a new approach for designing multi-user, Web-enabled…
Yeom, Jeong Seon; Jung, Bang Chul; Jin, Hu
2018-01-01
In this paper, we propose a novel low-complexity multi-user superposition transmission (MUST) technique for 5G downlink networks, which allows multiple cell-edge users to be multiplexed with a single cell-center user. We call the proposed technique diversity-controlled MUST technique since the cell-center user enjoys the frequency diversity effect via signal repetition over multiple orthogonal frequency division multiplexing (OFDM) sub-carriers. We assume that a base station is equipped with a single antenna but users are equipped with multiple antennas. In addition, we assume that the quadrature phase shift keying (QPSK) modulation is used for users. We mathematically analyze the bit error rate (BER) of both cell-edge users and cell-center users, which is the first theoretical result in the literature to the best of our knowledge. The mathematical analysis is validated through extensive link-level simulations. PMID:29439413
Yeom, Jeong Seon; Chu, Eunmi; Jung, Bang Chul; Jin, Hu
2018-02-10
In this paper, we propose a novel low-complexity multi-user superposition transmission (MUST) technique for 5G downlink networks, which allows multiple cell-edge users to be multiplexed with a single cell-center user. We call the proposed technique diversity-controlled MUST technique since the cell-center user enjoys the frequency diversity effect via signal repetition over multiple orthogonal frequency division multiplexing (OFDM) sub-carriers. We assume that a base station is equipped with a single antenna but users are equipped with multiple antennas. In addition, we assume that the quadrature phase shift keying (QPSK) modulation is used for users. We mathematically analyze the bit error rate (BER) of both cell-edge users and cell-center users, which is the first theoretical result in the literature to the best of our knowledge. The mathematical analysis is validated through extensive link-level simulations.
Users of the main smartphone operating systems (iOS, Android) differ only little in personality
Stieger, Stefan; Reips, Ulf-Dietrich
2017-01-01
The increasingly widespread use of mobile phone applications (apps) as research tools and cost-effective means of vast data collection raises new methodological challenges. In recent years, it has become a common practice for scientists to design apps that run only on a single operating system, thereby excluding large numbers of users who use a different operating system. However, empirical evidence investigating any selection biases that might result thereof is scarce. Henceforth, we conducted two studies drawing from a large multi-national (Study 1; N = 1,081) and a German-speaking sample (Study 2; N = 2,438). As such Study 1 compared iOS and Android users across an array of key personality traits (i.e., well-being, self-esteem, willingness to take risks, optimism, pessimism, Dark Triad, and the Big Five). Focusing on Big Five personality traits in a broader scope, in addition to smartphone users, Study 2 also examined users of the main computer operating systems (i.e., Mac OS, Windows). In both studies, very few significant differences were found, all of which were of small or even tiny effect size mostly disappearing after sociodemographics had been controlled for. Taken together, minor differences in personality seem to exist, but they are of small to negligible effect size (ranging from OR = 0.919 to 1.344 (Study 1), ηp2 = .005 to .036 (Study 2), respectively) and may reflect differences in sociodemographic composition, rather than operating system of smartphone users. PMID:28467473
Users of the main smartphone operating systems (iOS, Android) differ only little in personality.
Götz, Friedrich M; Stieger, Stefan; Reips, Ulf-Dietrich
2017-01-01
The increasingly widespread use of mobile phone applications (apps) as research tools and cost-effective means of vast data collection raises new methodological challenges. In recent years, it has become a common practice for scientists to design apps that run only on a single operating system, thereby excluding large numbers of users who use a different operating system. However, empirical evidence investigating any selection biases that might result thereof is scarce. Henceforth, we conducted two studies drawing from a large multi-national (Study 1; N = 1,081) and a German-speaking sample (Study 2; N = 2,438). As such Study 1 compared iOS and Android users across an array of key personality traits (i.e., well-being, self-esteem, willingness to take risks, optimism, pessimism, Dark Triad, and the Big Five). Focusing on Big Five personality traits in a broader scope, in addition to smartphone users, Study 2 also examined users of the main computer operating systems (i.e., Mac OS, Windows). In both studies, very few significant differences were found, all of which were of small or even tiny effect size mostly disappearing after sociodemographics had been controlled for. Taken together, minor differences in personality seem to exist, but they are of small to negligible effect size (ranging from OR = 0.919 to 1.344 (Study 1), ηp2 = .005 to .036 (Study 2), respectively) and may reflect differences in sociodemographic composition, rather than operating system of smartphone users.
Bernier, Eveline; Gosselin, Pierre; Badard, Thierry; Bédard, Yvan
2009-04-03
Climate change has a significant impact on population health. Population vulnerabilities depend on several determinants of different types, including biological, psychological, environmental, social and economic ones. Surveillance of climate-related health vulnerabilities must take into account these different factors, their interdependence, as well as their inherent spatial and temporal aspects on several scales, for informed analyses. Currently used technology includes commercial off-the-shelf Geographic Information Systems (GIS) and Database Management Systems with spatial extensions. It has been widely recognized that such OLTP (On-Line Transaction Processing) systems were not designed to support complex, multi-temporal and multi-scale analysis as required above. On-Line Analytical Processing (OLAP) is central to the field known as BI (Business Intelligence), a key field for such decision-support systems. In the last few years, we have seen a few projects that combine OLAP and GIS to improve spatio-temporal analysis and geographic knowledge discovery. This has given rise to SOLAP (Spatial OLAP) and a new research area. This paper presents how SOLAP and climate-related health vulnerability data were investigated and combined to facilitate surveillance. Based on recent spatial decision-support technologies, this paper presents a spatio-temporal web-based application that goes beyond GIS applications with regard to speed, ease of use, and interactive analysis capabilities. It supports the multi-scale exploration and analysis of integrated socio-economic, health and environmental geospatial data over several periods. This project was meant to validate the potential of recent technologies to contribute to a better understanding of the interactions between public health and climate change, and to facilitate future decision-making by public health agencies and municipalities in Canada and elsewhere. The project also aimed at integrating an initial collection of geo-referenced multi-scale indicators that were identified by Canadian specialists and end-users as relevant for the surveillance of the public health impacts of climate change. This system was developed in a multidisciplinary context involving researchers, policy makers and practitioners, using BI and web-mapping concepts (more particularly SOLAP technologies), while exploring new solutions for frequent automatic updating of data and for providing contextual warnings for users (to minimize the risk of data misinterpretation). According to the project participants, the final system succeeds in facilitating surveillance activities in a way not achievable with today's GIS. Regarding the experiments on frequent automatic updating and contextual user warnings, the results obtained indicate that these are meaningful and achievable goals but they still require research and development for their successful implementation in the context of surveillance and multiple organizations. Surveillance of climate-related health vulnerabilities may be more efficiently supported using a combination of BI and GIS concepts, and more specifically, SOLAP technologies (in that it facilitates and accelerates multi-scale spatial and temporal analysis to a point where a user can maintain an uninterrupted train of thought by focussing on "what" she/he wants (not on "how" to get it) and always obtain instant answers, including to the most complex queries that take minutes or hours with OLTP systems (e.g., aggregated, temporal, comparative)). The developed system respects Newell's cognitive band of 10 seconds when performing knowledge discovery (exploring data, looking for hypotheses, validating models). The developed system provides new operators for easily and rapidly exploring multidimensional data at different levels of granularity, for different regions and epochs, and for visualizing the results in synchronized maps, tables and charts. It is naturally adapted to deal with multiscale indicators such as those used in the surveillance community, as confirmed by this project's end-users.
Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA)
2013-07-24
ISS036-E-024569 (24 July 2013) --- European Space Agency astronaut Luca Parmitano, Expedition 36 flight engineer, works on the Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA) at a maintenance work station in the Harmony node of the International Space Station.
Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA)
2013-07-24
ISS036-E-024605 (24 July 2013) --- European Space Agency astronaut Luca Parmitano, Expedition 36 flight engineer, works on the Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA) at a maintenance work station in the Harmony node of the International Space Station.
Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA)
2013-07-24
ISS036-E-024637 (24 July 2013) --- European Space Agency astronaut Luca Parmitano, Expedition 36 flight engineer, works on the Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA) at a maintenance work station in the Harmony node of the International Space Station.
A system architecture for an advanced Canadian wideband mobile satellite system
NASA Technical Reports Server (NTRS)
Takats, P.; Keelty, M.; Moody, H.
1993-01-01
In this paper, the system architecture for an advanced Canadian ka-band geostationary mobile satellite system is described, utilizing hopping spot beams to support a 256 kbps wideband service for both N-ISDN and packet-switched interconnectivity to small briefcase-size portable and mobile terminals. An assessment is given of the technical feasibility of the satellite payload and terminal design in the post year 2000 timeframe. The satellite payload includes regeneration and on-board switching to permit single hop interconnectivity between mobile terminals. The mobile terminal requires antenna tracking and platform stabilization to ensure acquisition of the satellite signal. The potential user applications targeted for this wideband service includes: home-office, multimedia, desk-top (PC) videoconferencing, digital audio broadcasting, single and multi-user personal communications.
SPARK: A Framework for Multi-Scale Agent-Based Biomedical Modeling.
Solovyev, Alexey; Mikheev, Maxim; Zhou, Leming; Dutta-Moscato, Joyeeta; Ziraldo, Cordelia; An, Gary; Vodovotz, Yoram; Mi, Qi
2010-01-01
Multi-scale modeling of complex biological systems remains a central challenge in the systems biology community. A method of dynamic knowledge representation known as agent-based modeling enables the study of higher level behavior emerging from discrete events performed by individual components. With the advancement of computer technology, agent-based modeling has emerged as an innovative technique to model the complexities of systems biology. In this work, the authors describe SPARK (Simple Platform for Agent-based Representation of Knowledge), a framework for agent-based modeling specifically designed for systems-level biomedical model development. SPARK is a stand-alone application written in Java. It provides a user-friendly interface, and a simple programming language for developing Agent-Based Models (ABMs). SPARK has the following features specialized for modeling biomedical systems: 1) continuous space that can simulate real physical space; 2) flexible agent size and shape that can represent the relative proportions of various cell types; 3) multiple spaces that can concurrently simulate and visualize multiple scales in biomedical models; 4) a convenient graphical user interface. Existing ABMs of diabetic foot ulcers and acute inflammation were implemented in SPARK. Models of identical complexity were run in both NetLogo and SPARK; the SPARK-based models ran two to three times faster.
NASA Astrophysics Data System (ADS)
Xu, Kui; Sun, Xiaoli; Zhang, Dongmei
2016-10-01
This paper investigates the spectral and energy efficiencies of a multi-pair two-way amplify-and-forward (AF) relay system over Ricean fading channels, where multiple user-pairs exchange information within pair through a relay with very large number of antennas, while each user equipped with a single antenna. Firstly, beamforming matrixe of zero-forcing reception/zero-forcing transmission (ZFR/ZFT) with imperfect channel state information (CSI) at the relay is given. Then, the unified asymptotic signal-to-interference-plus-noise ratio (SINR) expressions with imperfect CSI are obtained analytically. Finally, two power scaling schemes are proposed and the asymptotic spectral and energy efficiencies based on the proposed power scaling schemes are derived and verified by the Monte-Carlo simulations. Theoretical analyses and simulation results show that with imperfect CSI, if the number of relay antennas grows asymptotically large, we need cut down the transmit power of each user and relay to different proportion when the Ricean K-factor is non-zero and zero (Rayleigh fading) in order to maintain a desirable rate.
Evaluation of an Integrated Multi-Task Machine Learning System with Humans in the Loop
2007-01-01
machine learning components natural language processing, and optimization...was examined with a test explicitly developed to measure the impact of integrated machine learning when used by a human user in a real world setting...study revealed that integrated machine learning does produce a positive impact on overall performance. This paper also discusses how specific machine learning components contributed to human-system
Xu, Qian; Tan, Chengxiang; Fan, Zhijie; Zhu, Wenye; Xiao, Ya; Cheng, Fujia
2018-01-01
Nowadays, fog computing provides computation, storage, and application services to end users in the Internet of Things. One of the major concerns in fog computing systems is how fine-grained access control can be imposed. As a logical combination of attribute-based encryption and attribute-based signature, Attribute-based Signcryption (ABSC) can provide confidentiality and anonymous authentication for sensitive data and is more efficient than traditional “encrypt-then-sign” or “sign-then-encrypt” strategy. Thus, ABSC is suitable for fine-grained access control in a semi-trusted cloud environment and is gaining more and more attention recently. However, in many existing ABSC systems, the computation cost required for the end users in signcryption and designcryption is linear with the complexity of signing and encryption access policy. Moreover, only a single authority that is responsible for attribute management and key generation exists in the previous proposed ABSC schemes, whereas in reality, mostly, different authorities monitor different attributes of the user. In this paper, we propose OMDAC-ABSC, a novel data access control scheme based on Ciphertext-Policy ABSC, to provide data confidentiality, fine-grained control, and anonymous authentication in a multi-authority fog computing system. The signcryption and designcryption overhead for the user is significantly reduced by outsourcing the undesirable computation operations to fog nodes. The proposed scheme is proven to be secure in the standard model and can provide attribute revocation and public verifiability. The security analysis, asymptotic complexity comparison, and implementation results indicate that our construction can balance the security goals with practical efficiency in computation. PMID:29772840
Lima, Ana Carolina E S; de Castro, Leandro Nunes
2014-10-01
Social media allow web users to create and share content pertaining to different subjects, exposing their activities, opinions, feelings and thoughts. In this context, online social media has attracted the interest of data scientists seeking to understand behaviours and trends, whilst collecting statistics for social sites. One potential application for these data is personality prediction, which aims to understand a user's behaviour within social media. Traditional personality prediction relies on users' profiles, their status updates, the messages they post, etc. Here, a personality prediction system for social media data is introduced that differs from most approaches in the literature, in that it works with groups of texts, instead of single texts, and does not take users' profiles into account. Also, the proposed approach extracts meta-attributes from texts and does not work directly with the content of the messages. The set of possible personality traits is taken from the Big Five model and allows the problem to be characterised as a multi-label classification task. The problem is then transformed into a set of five binary classification problems and solved by means of a semi-supervised learning approach, due to the difficulty in annotating the massive amounts of data generated in social media. In our implementation, the proposed system was trained with three well-known machine-learning algorithms, namely a Naïve Bayes classifier, a Support Vector Machine, and a Multilayer Perceptron neural network. The system was applied to predict the personality of Tweets taken from three datasets available in the literature, and resulted in an approximately 83% accurate prediction, with some of the personality traits presenting better individual classification rates than others. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
McLaughlin, Brian J.; Barrett, Larry K.
2012-01-01
Common practice in the development of simulation systems is meeting all user requirements within a single instantiation. The Joint Polar Satellite System (JPSS) presents a unique challenge to establish a simulation environment that meets the needs of a diverse user community while also spanning a multi-mission environment over decades of operation. In response, the JPSS Flight Vehicle Test Suite (FVTS) is architected with an extensible infrastructure that supports the operation of multiple observatory simulations for a single mission and multiple mission within a common system perimeter. For the JPSS-1 satellite, multiple fidelity flight observatory simulations are necessary to support the distinct user communities consisting of the Common Ground System development team, the Common Ground System Integration & Test team, and the Mission Rehearsal Team/Mission Operations Team. These key requirements present several challenges to FVTS development. First, the FVTS must ensure all critical user requirements are satisfied by at least one fidelity instance of the observatory simulation. Second, the FVTS must allow for tailoring of the system instances to function in diverse operational environments from the High-security operations environment at NOAA Satellite Operations Facility (NSOF) to the ground system factory floor. Finally, the FVTS must provide the ability to execute sustaining engineering activities on a subset of the system without impacting system availability to parallel users. The FVTS approach of allowing for multiple fidelity copies of observatory simulations represents a unique concept in simulator capability development and corresponds to the JPSS Ground System goals of establishing a capability that is flexible, extensible, and adaptable.
Yeaton, K
1994-01-01
Many patients cite comfort as a primary factor in their success or failure with soft contact lenses. In an effort to further meet the needs of these patients, eye-care professionals must place more emphasis on dispensing a lens type and lens-care system that maximize patient satisfaction and thus provide a higher quality of service. This study delineated patient-defined quality and comfort as they relate to lens-care solutions. Five hundred ninety-nine U.S. practices were each asked to switch 25 of their patients to Opti-Free Lens Care from their currently used lens-care system (52% ReNu Multi-Purpose Solution, 20% AOSept System) for 2 weeks. Data were collected from 14,455 patients who completed the post-trial interview. At the time of the callback interview, 81% of respondents (78% ReNu users, 82% AOSept users) were using the Opti-Free System. Of these patients, 85% (84% previous ReNu users, 87% previous AOSept users) rated Opti-Free Lens Care more comfortable than or as comfortable as their previous system. These findings demonstrate differences in patient comfort among Opti-Free, AOSept, and ReNu. Eye-care professionals should consider relative comfort when dispensing lens-care systems, as this may affect patient-defined quality.
INL Multi-Robot Control Interface
DOE Office of Scientific and Technical Information (OSTI.GOV)
2005-03-30
The INL Multi-Robot Control Interface controls many robots through a single user interface. The interface includes a robot display window for each robot showing the robotâs condition. More than one window can be used depending on the number of robots. The user interface also includes a robot control window configured to receive commands for sending to the respective robot and a multi-robot common window showing information received from each robot.
2009-06-01
to floating point , to multi-level logic. 2 Overview Self-aware computation can be distinguished from existing computational models which are...systems have advanced to the point that the time is ripe to realize such a system. To illustrate, let us examine each of the key aspects of self...servers for each service, there are no single points of failure in the system. If an OS or user core has a failure, one of several introspection cores
On Performance of Linear Multiuser Detectors for Wireless Multimedia Applications
NASA Astrophysics Data System (ADS)
Agarwal, Rekha; Reddy, B. V. R.; Bindu, E.; Nayak, Pinki
In this paper, performance of different multi-rate schemes in DS-CDMA system is evaluated. The analysis of multirate linear multiuser detectors with multiprocessing gain is analyzed for synchronous Code Division Multiple Access (CDMA) systems. Variable data rate is achieved by varying the processing gain. Our conclusion is that bit error rate for multirate and single rate systems can be made same with a tradeoff with number of users in linear multiuser detectors.
NASA Astrophysics Data System (ADS)
Saha, Rony Kumer; Aswakul, Chaodit
2017-01-01
In this paper, a multi-band enabled femtocell base station (FCBS) and user equipment (UE) architecture is proposed in a multi-tier network that consists of small cells, including femtocells and picocells deployed over the coverage of a macrocell for splitting uplink and downlink (UL/DL) as well as control-plane and user-plane (C-/U-plane) for 5G mobile networks. Since splitting is performed at the same FCBS, we define this architecture as the same base station based split architecture (SBSA). For multiple bands, we consider co-channel (CC) microwave and different frequency (DF) 60 GHz millimeter wave (mmWave) bands for FCBSs and UEs with respect to the microwave band used by their over-laid macrocell base station. All femtocells are assumed to be deployed in a 3-dimensional multi-storage building. For CC microwave band, cross-tier CC interference of femtocells with macrocell is avoided using almost blank subframe based enhanced inter-cell interference coordination techniques. The co-existence of CC microwave and DF mmWave bands for SBSA on the same FCBS and UE is first studied to show their performance disparities in terms of system capacity and spectral efficiency in order to provide incentives for employing multiple bands at the same FCBS and UE and identify a suitable band for routing decoupled UL/DL or C-/U-plane traffic. We then present a number of disruptive architectural design alternatives of multi-band enabled SBSA for 5G mobile networks for UL/DL and C-/U-plane splitting, including a disruptive and complete splitting of UL/DL and C-/U-plane as well as a combined UL/DL and C-/U-plane splitting, by exploiting dual connectivity on CC microwave and DF mmWave bands. The outperformances of SBSA in terms of system level capacity, average spectral efficiency, energy efficiency, and control-plane overhead traffic capacity in comparison with different base stations based split architecture (DBSA) are shown. Finally, a number of technical and business perspectives as well as key research issues of SBSA are discussed.
Algorithmic and user study of an autocompletion algorithm on a large medical vocabulary.
Sevenster, Merlijn; van Ommering, Rob; Qian, Yuechen
2012-02-01
Autocompletion supports human-computer interaction in software applications that let users enter textual data. We will be inspired by the use case in which medical professionals enter ontology concepts, catering the ongoing demand for structured and standardized data in medicine. Goal is to give an algorithmic analysis of one particular autocompletion algorithm, called multi-prefix matching algorithm, which suggests terms whose words' prefixes contain all words in the string typed by the user, e.g., in this sense, opt ner me matches optic nerve meningioma. Second we aim to investigate how well it supports users entering concepts from a large and comprehensive medical vocabulary (snomed ct). We give a concise description of the multi-prefix algorithm, and sketch how it can be optimized to meet required response time. Performance will be compared to a baseline algorithm, which gives suggestions that extend the string typed by the user to the right, e.g. optic nerve m gives optic nerve meningioma, but opt ner me does not. We conduct a user experiment in which 12 participants are invited to complete 40 snomed ct terms with the baseline algorithm and another set of 40 snomed ct terms with the multi-prefix algorithm. Our results show that users need significantly fewer keystrokes when supported by the multi-prefix algorithm than when supported by the baseline algorithm. The proposed algorithm is a competitive candidate for searching and retrieving terms from a large medical ontology. Copyright © 2011 Elsevier Inc. All rights reserved.
Global Village as Virtual Community (On Writing, Thinking, and Teacher Education).
ERIC Educational Resources Information Center
Polin, Linda
1993-01-01
Describes virtual communities known as Multi-User Simulated Environment (MUSE) or Multi-User Object Oriented environment (MOO), text-based computer "communities" whose inhabitants are a combination of the real people and constructed objects that people agree to treat as real. Describes their uses in the classroom. (SR)
Dabek, Filip; Caban, Jesus J
2017-01-01
Despite the recent popularity of visual analytics focusing on big data, little is known about how to support users that use visualization techniques to explore multi-dimensional datasets and accomplish specific tasks. Our lack of models that can assist end-users during the data exploration process has made it challenging to learn from the user's interactive and analytical process. The ability to model how a user interacts with a specific visualization technique and what difficulties they face are paramount in supporting individuals with discovering new patterns within their complex datasets. This paper introduces the notion of visualization systems understanding and modeling user interactions with the intent of guiding a user through a task thereby enhancing visual data exploration. The challenges faced and the necessary future steps to take are discussed; and to provide a working example, a grammar-based model is presented that can learn from user interactions, determine the common patterns among a number of subjects using a K-Reversible algorithm, build a set of rules, and apply those rules in the form of suggestions to new users with the goal of guiding them along their visual analytic process. A formal evaluation study with 300 subjects was performed showing that our grammar-based model is effective at capturing the interactive process followed by users and that further research in this area has the potential to positively impact how users interact with a visualization system.
Secure multi-party communication with quantum key distribution managed by trusted authority
Nordholt, Jane Elizabeth; Hughes, Richard John; Peterson, Charles Glen
2013-07-09
Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD are extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.
Secure multi-party communication with quantum key distribution managed by trusted authority
Hughes, Richard John; Nordholt, Jane Elizabeth; Peterson, Charles Glen
2015-01-06
Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD are extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.
TADS--A CFD-Based Turbomachinery Analysis and Design System with GUI: User's Manual. 2.0
NASA Technical Reports Server (NTRS)
Koiro, M. J.; Myers, R. A.; Delaney, R. A.
1999-01-01
The primary objective of this study was the development of a Computational Fluid Dynamics (CFD) based turbomachinery airfoil analysis and design system, controlled by a Graphical User Interface (GUI). The computer codes resulting from this effort are referred to as TADS (Turbomachinery Analysis and Design System). This document is intended to serve as a User's Manual for the computer programs which comprise the TADS system, developed under Task 18 of NASA Contract NAS3-27350, ADPAC System Coupling to Blade Analysis & Design System GUI and Task 10 of NASA Contract NAS3-27394, ADPAC System Coupling to Blade Analysis & Design System GUI, Phase II-Loss, Design and, Multi-stage Analysis. TADS couples a throughflow solver (ADPAC) with a quasi-3D blade-to-blade solver (RVCQ3D) in an interactive package. Throughflow analysis and design capability was developed in ADPAC through the addition of blade force and blockage terms to the governing equations. A GUI was developed to simplify user input and automate the many tasks required to perform turbomachinery analysis and design. The coupling of the various programs was done in such a way that alternative solvers or grid generators could be easily incorporated into the TADS framework. Results of aerodynamic calculations using the TADS system are presented for a highly loaded fan, a compressor stator, a low speed turbine blade and a transonic turbine vane.
Secoli, R; Zondervan, D; Reinkensmeyer, D
2012-01-01
For children with a severe disability, such as can arise from cerebral palsy, becoming independent in mobility is a critical goal. Currently, however, driver's training for powered wheelchair use is labor intensive, requiring hand-over-hand assistance from a skilled therapist to keep the trainee safe. This paper describes the design of a mixed reality environment for semi-autonomous training of wheelchair driving skills. In this system, the wheelchair is used as the gaming input device, and users train driving skills by maneuvering through floor-projected games created with a multi-projector system and a multi-camera tracking system. A force feedback joystick assists in steering and enhances safety.
Novel interactive virtual showcase based on 3D multitouch technology
NASA Astrophysics Data System (ADS)
Yang, Tao; Liu, Yue; Lu, You; Wang, Yongtian
2009-11-01
A new interactive virtual showcase is proposed in this paper. With the help of virtual reality technology, the user of the proposed system can watch the virtual objects floating in the air from all four sides and interact with the virtual objects by touching the four surfaces of the virtual showcase. Unlike traditional multitouch system, this system cannot only realize multi-touch on a plane to implement 2D translation, 2D scaling, and 2D rotation of the objects; it can also realize the 3D interaction of the virtual objects by recognizing and analyzing the multi-touch that can be simultaneously captured from the four planes. Experimental results show the potential of the proposed system to be applied in the exhibition of historical relics and other precious goods.
MMX-I: A data-processing software for multi-modal X-ray imaging and tomography
NASA Astrophysics Data System (ADS)
Bergamaschi, A.; Medjoubi, K.; Messaoudi, C.; Marco, S.; Somogyi, A.
2017-06-01
Scanning hard X-ray imaging allows simultaneous acquisition of multimodal information, including X-ray fluorescence, absorption, phase and dark-field contrasts, providing structural and chemical details of the samples. Combining these scanning techniques with the infrastructure developed for fast data acquisition at Synchrotron Soleil permits to perform multimodal imaging and tomography during routine user experiments at the Nanoscopium beamline. A main challenge of such imaging techniques is the online processing and analysis of the generated very large volume (several hundreds of Giga Bytes) multimodal data-sets. This is especially important for the wide user community foreseen at the user oriented Nanoscopium beamline (e.g. from the fields of Biology, Life Sciences, Geology, Geobiology), having no experience in such data-handling. MMX-I is a new multi-platform open-source freeware for the processing and reconstruction of scanning multi-technique X-ray imaging and tomographic datasets. The MMX-I project aims to offer, both expert users and beginners, the possibility of processing and analysing raw data, either on-site or off-site. Therefore we have developed a multi-platform (Mac, Windows and Linux 64bit) data processing tool, which is easy to install, comprehensive, intuitive, extendable and user-friendly. MMX-I is now routinely used by the Nanoscopium user community and has demonstrated its performance in treating big data.
Security enhanced multi-factor biometric authentication scheme using bio-hash function.
Choi, Younsung; Lee, Youngsook; Moon, Jongho; Won, Dongho
2017-01-01
With the rapid development of personal information and wireless communication technology, user authentication schemes have been crucial to ensure that wireless communications are secure. As such, various authentication schemes with multi-factor authentication have been proposed to improve the security of electronic communications. Multi-factor authentication involves the use of passwords, smart cards, and various biometrics to provide users with the utmost privacy and data protection. Cao and Ge analyzed various authentication schemes and found that Younghwa An's scheme was susceptible to a replay attack where an adversary masquerades as a legal server and a user masquerading attack where user anonymity is not provided, allowing an adversary to execute a password change process by intercepting the user's ID during login. Cao and Ge improved upon Younghwa An's scheme, but various security problems remained. This study demonstrates that Cao and Ge's scheme is susceptible to a biometric recognition error, slow wrong password detection, off-line password attack, user impersonation attack, ID guessing attack, a DoS attack, and that their scheme cannot provide session key agreement. Then, to address all weaknesses identified in Cao and Ge's scheme, this study proposes a security enhanced multi-factor biometric authentication scheme and provides a security analysis and formal analysis using Burrows-Abadi-Needham logic. Finally, the efficiency analysis reveals that the proposed scheme can protect against several possible types of attacks with only a slightly high computational cost.
Schaarup, Clara; Hartvigsen, Gunnar; Larsen, Lars Bo; Tan, Zheng-Hua; Årsand, Eirik; Hejlesen, Ole Kristian
2015-01-01
The Online Diabetes Exercise System was developed to motivate people with Type 2 diabetes to do a 25 minutes low-volume high-intensity interval training program. In a previous multi-method evaluation of the system, several usability issues were identified and corrected. Despite the thorough testing, it was unclear whether all usability problems had been identified using the multi-method evaluation. Our hypothesis was that adding the eye-tracking triangulation to the multi-method evaluation would increase the accuracy and completeness when testing the usability of the system. The study design was an Eye-tracking Triangulation; conventional eye-tracking with predefined tasks followed by The Post-Experience Eye-Tracked Protocol (PEEP). Six Areas of Interests were the basis for the PEEP-session. The eye-tracking triangulation gave objective and subjective results, which are believed to be highly relevant for designing, implementing, evaluating and optimizing systems in the field of health informatics. Future work should include testing the method on a larger and more representative group of users and apply the method on different system types.
System Engineering Strategy for Distributed Multi-Purpose Simulation Architectures
NASA Technical Reports Server (NTRS)
Bhula, Dlilpkumar; Kurt, Cindy Marie; Luty, Roger
2007-01-01
This paper describes the system engineering approach used to develop distributed multi-purpose simulations. The multi-purpose simulation architecture focuses on user needs, operations, flexibility, cost and maintenance. This approach was used to develop an International Space Station (ISS) simulator, which is called the International Space Station Integrated Simulation (ISIS)1. The ISIS runs unmodified ISS flight software, system models, and the astronaut command and control interface in an open system design that allows for rapid integration of multiple ISS models. The initial intent of ISIS was to provide a distributed system that allows access to ISS flight software and models for the creation, test, and validation of crew and ground controller procedures. This capability reduces the cost and scheduling issues associated with utilizing standalone simulators in fixed locations, and facilitates discovering unknowns and errors earlier in the development lifecycle. Since its inception, the flexible architecture of the ISIS has allowed its purpose to evolve to include ground operator system and display training, flight software modification testing, and as a realistic test bed for Exploration automation technology research and development.
A study on the achievable data rate in massive MIMO system
NASA Astrophysics Data System (ADS)
Salh, Adeeb; Audah, Lukman; Shah, Nor Shahida M.; Hamzah, Shipun A.
2017-09-01
The achievable high data rates depend on the ability of massive multi-input-multi-output (MIMO) for the fifth-generation (5G) cellular networks, where the massive MIMO systems can support very high energy and spectral efficiencies. A major challenge in mobile broadband networks is how to support the throughput in the future 5G, where the highlight of 5G expected to provide high speed internet for every user. The performance massive MIMO system increase with linear minimum mean square error (MMSE), zero forcing (ZF) and maximum ratio transmission (MRT) when the number of antennas increases to infinity, by deriving the closed-form approximation for achievable data rate expressions. Meanwhile, the high signal-to-noise ratio (SNR) can be mitigated by using MMSE, ZF and MRT, which are used to suppress the inter-cell interference signals between neighboring cells. The achievable sum rate for MMSE is improved based on the distributed users inside cell, mitigated the inter-cell interference caused when send the same signal by other cells. By contrast, MMSE is better than ZF in perfect channel state information (CSI) for approximately 20% of the achievable sum rate.
CPM Signals for Satellite Navigation in the S and C Bands.
Xue, Rui; Sun, Yanbo; Zhao, Danfeng
2015-06-05
Frequency allocations in the L band suitable for global navigation satellite system (GNSS) services are getting crowded and system providers face an ever tougher job when they try to bring in new signals and services while maintaining radio frequency compatibility. With the successive opening of the S and C bands to GNSS service, the multi-band combined navigation is predicted to become a key technology for future high-precision positioning navigation systems, and a single modulation scheme satisfying the requirements in each band is a promising solution for reducing user terminal complexity. A universal modulation scheme based on the continuous phase modulation (CPM) family suitable for the above bands' demands is proposed. Moreover, this paper has put forward two specific CPM signals for the S and C bands, respectively. Then the proposed modulation schemes, together with existing candidates, are comprehensively evaluated. Simulation results show that the proposed CPM signals can not only satisfy the constraint condition of compatibility in different bands well and reduce user terminal complexity, but also provide superior performance in terms of tracking accuracy, multi-path mitigation and anti-jamming compared to other candidate modulation schemes.
NASA Astrophysics Data System (ADS)
Redfern, Andrew; Koplow, Michael; Wright, Paul
2007-01-01
Most residential heating, ventilating, and air-conditioning (HVAC) systems utilize a single zone for conditioning air throughout the entire house. While inexpensive, these systems lead to wide temperature distributions and inefficient cooling due to the difference in thermal loads in different rooms. The end result is additional cost to the end user because the house is over conditioned. To reduce the total amount of energy used in a home and to increase occupant comfort there is a need for a better control system using multiple temperature zones. Typical multi-zone systems are costly and require extensive infrastructure to function. Recent advances in wireless sensor networks (WSNs) have enabled a low cost drop-in wireless vent register control system. The register control system is controlled by a master controller unit, which collects sensor data from a distributed wireless sensor network. Each sensor node samples local settings (occupancy, light, humidity and temperature) and reports the data back to the master control unit. The master control unit compiles the incoming data and then actuates the vent resisters to control the airflow throughout the house. The control system also utilizes a smart thermostat with a movable set point to enable the user to define their given comfort levels. The new system can reduce the run time of the HVAC system and thus decreasing the amount of energy used and increasing the comfort of the home occupations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Philip, Bobby
2012-06-01
The Advanced Multi-Physics (AMP) code, in its present form, will allow a user to build a multi-physics application code for existing mechanics and diffusion operators and extend them with user-defined material models and new physics operators. There are examples that demonstrate mechanics, thermo-mechanics, coupled diffusion, and mechanical contact. The AMP code is designed to leverage a variety of mathematical solvers (PETSc, Trilinos, SUNDIALS, and AMP solvers) and mesh databases (LibMesh and AMP) in a consistent interchangeable approach.
A New Multi-Agent Approach to Adaptive E-Education
NASA Astrophysics Data System (ADS)
Chen, Jing; Cheng, Peng
Improving customer satisfaction degree is important in e-Education. This paper describes a new approach to adaptive e-Education taking into account the full spectrum of Web service techniques and activities. It presents a multi-agents architecture based on artificial psychology techniques, which makes the e-Education process both adaptable and dynamic, and hence up-to-date. Knowledge base techniques are used to support the e-Education process, and artificial psychology techniques to deal with user psychology, which makes the e-Education system more effective and satisfying.
Zhang, Baohong; Zhao, Shanrong; Neuhaus, Isaac
2018-05-03
We present a bioinformatics and systems biology visualization toolkit harmonizing real time interactive exploring and analyzing of big data, full-fledged customizing of look-n-feel, and producing multi-panel publication-ready figures in PDF format simultaneously. Source code and detailed user guides are available at http://canvasxpress.org, https://baohongz.github.io/canvasDesigner, and https://baohongz.github.io/canvasDesigner/demo_video.html. isaac.neuhaus@bms.com, baohong.zhang@pfizer.com, shanrong.zhao@pfizer.com. Supplementary materials are available at https://goo.gl/1uQygs.
Using Markov Chains and Multi-Objective Optimization for Energy-Efficient Context Recognition.
Janko, Vito; Luštrek, Mitja
2017-12-29
The recognition of the user's context with wearable sensing systems is a common problem in ubiquitous computing. However, the typically small battery of such systems often makes continuous recognition impractical. The strain on the battery can be reduced if the sensor setting is adapted to each context. We propose a method that efficiently finds near-optimal sensor settings for each context. It uses Markov chains to simulate the behavior of the system in different configurations and the multi-objective genetic algorithm to find a set of good non-dominated configurations. The method was evaluated on three real-life datasets and found good trade-offs between the system's energy expenditure and the system's accuracy. One of the solutions, for example, consumed five-times less energy than the default one, while sacrificing only two percentage points of accuracy.
On the Design of the Peer-Assisted UGC VoD System
NASA Astrophysics Data System (ADS)
Wan, Yi; Asaka, Takuya; Takahashi, Tatsuro
User Generated Content (UGC) VoD services such as YouTube are becoming more and more popular, and their maintenance costs are growing as well. Many P2P solutions have been proposed to reduce server load in such systems, but almost all of them focus on the single-video approach, which only has limited effect on the systems serving short videos such as UGC. The purpose of this paper is to investigate the potential of an alternative approach, the multi-video approach, and we use a very simple method called collaborative caching to show that methods using the multi-video approach are generally more suitable for current UGC VoD systems. We also study the influence of the major design factors through simulations and provide guidelines for efficiently building systems with this method.
NASA Astrophysics Data System (ADS)
Klein, Matthias; Vaes, W. H. J.; Fabriek, B.; Sandman, H.; Mous, D. J. W.; Gottdang, A.
2013-01-01
The Netherlands Organization for Applied Scientific Research (TNO) has installed a compact 1 MV multi-element AMS system manufactured by High Voltage Engineering Europa B.V., The Netherlands. TNO performs clinical research programs for pharmaceutical and innovative foods industry to obtain early pharmacokinetic data and to provide anti-osteoporotic efficacy data of new treatments. The AMS system will analyze carbon, iodine and calcium samples for this purpose. The first measurements on blank samples indicate background levels in the low 10-12 for calcium and iodine, making the system well suited for these biomedical applications. Carbon blanks have been measured at low 10-16. For unattended, around-the-clock analysis, the system features the 200 sample version of the SO110 hybrid ion source and user friendly control software.
Batching System for Superior Service
NASA Technical Reports Server (NTRS)
2001-01-01
Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adamson, Ryan M.
Password management solutions exist, but few are designed for enterprise systems administrators sharing oncall rotations. Due to the Multi-Factor Level of Assurance 4 effort, DOE is now distributing PIV cards with cryptographically signed certificate and private key pairs to administrators and other security-significant users. We utilize this public key infrastructure (PKI) to encrypt passwords for other recipients in a secure way. This is cross platform (works on OSX and Linux systems), and has already been adopted internally by the NCCS systems administration staff to replace their old password book system.
NASA Technical Reports Server (NTRS)
DeGaudenzi, Riccardo; Giannetti, Filippo
1995-01-01
The downlink of a satellite-mobile personal communication system employing power-controlled Direct Sequence Code Division Multiple Access (DS-CDMA) and exploiting satellite-diversity is analyzed and its performance compared with a more traditional communication system utilizing single satellite reception. The analytical model developed has been thoroughly validated by means of extensive Monte Carlo computer simulations. It is shown how the capacity gain provided by diversity reception shrinks considerably in the presence of increasing traffic or in the case of light shadowing conditions. Moreover, the quantitative results tend to indicate that to combat system capacity reduction due to intra-system interference, no more than two satellites shall be active over the same region. To achieve higher system capacity, differently from terrestrial cellular systems, Multi-User Detection (MUD) techniques are likely to be required in the mobile user terminal, thus considerably increasing its complexity.
Heading Toward Launch with the Integrated Multi-Satellite Retrievals for GPM (IMERG)
NASA Technical Reports Server (NTRS)
Huffman, George J.; Bolvin, David T.; Nelkin, Eric J.; Adler, Robert F.
2012-01-01
The Day-l algorithm for computing combined precipitation estimates in GPM is the Integrated Multi-satellitE Retrievals for GPM (IMERG). We plan for the period of record to encompass both the TRMM and GPM eras, and the coverage to extend to fully global as experience is gained in the difficult high-latitude environment. IMERG is being developed as a unified U.S. algorithm that takes advantage of strengths in the three groups that are contributing expertise: 1) the TRMM Multi-satellite Precipitation Analysis (TMPA), which addresses inter-satellite calibration of precipitation estimates and monthly scale combination of satellite and gauge analyses; 2) the CPC Morphing algorithm with Kalman Filtering (KF-CMORPH), which provides quality-weighted time interpolation of precipitation patterns following cloud motion; and 3) the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks using a Cloud Classification System (PERSIANN-CCS), which provides a neural-network-based scheme for generating microwave-calibrated precipitation estimates from geosynchronous infrared brightness temperatures. In this talk we summarize the major building blocks and important design issues driven by user needs and practical data issues. One concept being pioneered by the IMERG team is that the code system should produce estimates for the same time period but at different latencies to support the requirements of different groups of users. Another user requirement is that all these runs must be reprocessed as new IMERG versions are introduced. IMERG's status at meeting time will be summarized, and the processing scenario in the transition from TRMM to GPM will be laid out. Initially, IMERG will be run with TRMM-based calibration, and then a conversion to a GPM-based calibration will be employed after the GPM sensor products are validated. A complete reprocessing will be computed, which will complete the transition from TMPA.
De Ceulaer, Geert; Bestel, Julie; Mülder, Hans E; Goldbeck, Felix; de Varebeke, Sebastien Pierre Janssens; Govaerts, Paul J
2016-05-01
Roger is a digital adaptive multi-channel remote microphone technology that wirelessly transmits a speaker's voice directly to a hearing instrument or cochlear implant sound processor. Frequency hopping between channels, in combination with repeated broadcast, avoids interference issues that have limited earlier generation FM systems. This study evaluated the benefit of the Roger Pen transmitter microphone in a multiple talker network (MTN) for cochlear implant users in a simulated noisy conversation setting. Twelve post-lingually deafened adult Advanced Bionics CII/HiRes 90K recipients were recruited. Subjects used a Naida CI Q70 processor with integrated Roger 17 receiver. The test environment simulated four people having a meal in a noisy restaurant, one the CI user (listener), and three companions (talkers) talking non-simultaneously in a diffuse field of multi-talker babble. Speech reception thresholds (SRTs) were determined without the Roger Pen, with one Roger Pen, and with three Roger Pens in an MTN. Using three Roger Pens in an MTN improved the SRT by 14.8 dB over using no Roger Pen, and by 13.1 dB over using a single Roger Pen (p < 0.0001). The Roger Pen in an MTN provided statistically and clinically significant improvement in speech perception in noise for Advanced Bionics cochlear implant recipients. The integrated Roger 17 receiver made it easy for users of the Naida CI Q70 processor to take advantage of the Roger system. The listening advantage and ease of use should encourage more clinicians to recommend and fit Roger in adult cochlear implant patients.
A grid generation system for multi-disciplinary design optimization
NASA Technical Reports Server (NTRS)
Jones, William T.; Samareh-Abolhassani, Jamshid
1995-01-01
A general multi-block three-dimensional volume grid generator is presented which is suitable for Multi-Disciplinary Design Optimization. The code is timely, robust, highly automated, and written in ANSI 'C' for platform independence. Algebraic techniques are used to generate and/or modify block face and volume grids to reflect geometric changes resulting from design optimization. Volume grids are generated/modified in a batch environment and controlled via an ASCII user input deck. This allows the code to be incorporated directly into the design loop. Generated volume grids are presented for a High Speed Civil Transport (HSCT) Wing/Body geometry as well a complex HSCT configuration including horizontal and vertical tails, engine nacelles and pylons, and canard surfaces.
Diverse applications of advanced man-telerobot interfaces
NASA Technical Reports Server (NTRS)
Mcaffee, Douglas A.
1991-01-01
Advancements in man-machine interfaces and control technologies used in space telerobotics and teleoperators have potential application wherever human operators need to manipulate multi-dimensional spatial relationships. Bilateral six degree-of-freedom position and force cues exchanged between the user and a complex system can broaden and improve the effectiveness of several diverse man-machine interfaces.
Towards Gesture-Based Multi-User Interactions in Collaborative Virtual Environments
NASA Astrophysics Data System (ADS)
Pretto, N.; Poiesi, F.
2017-11-01
We present a virtual reality (VR) setup that enables multiple users to participate in collaborative virtual environments and interact via gestures. A collaborative VR session is established through a network of users that is composed of a server and a set of clients. The server manages the communication amongst clients and is created by one of the users. Each user's VR setup consists of a Head Mounted Display (HMD) for immersive visualisation, a hand tracking system to interact with virtual objects and a single-hand joypad to move in the virtual environment. We use Google Cardboard as a HMD for the VR experience and a Leap Motion for hand tracking, thus making our solution low cost. We evaluate our VR setup though a forensics use case, where real-world objects pertaining to a simulated crime scene are included in a VR environment, acquired using a smartphone-based 3D reconstruction pipeline. Users can interact using virtual gesture-based tools such as pointers and rulers.
The image-interpretation-workstation of the future: lessons learned
NASA Astrophysics Data System (ADS)
Maier, S.; van de Camp, F.; Hafermann, J.; Wagner, B.; Peinsipp-Byma, E.; Beyerer, J.
2017-05-01
In recent years, professionally used workstations got increasingly complex and multi-monitor systems are more and more common. Novel interaction techniques like gesture recognition were developed but used mostly for entertainment and gaming purposes. These human computer interfaces are not yet widely used in professional environments where they could greatly improve the user experience. To approach this problem, we combined existing tools in our imageinterpretation-workstation of the future, a multi-monitor workplace comprised of four screens. Each screen is dedicated to a special task in the image interpreting process: a geo-information system to geo-reference the images and provide a spatial reference for the user, an interactive recognition support tool, an annotation tool and a reporting tool. To further support the complex task of image interpreting, self-developed interaction systems for head-pose estimation and hand tracking were used in addition to more common technologies like touchscreens, face identification and speech recognition. A set of experiments were conducted to evaluate the usability of the different interaction systems. Two typical extensive tasks of image interpreting were devised and approved by military personal. They were then tested with a current setup of an image interpreting workstation using only keyboard and mouse against our image-interpretationworkstation of the future. To get a more detailed look at the usefulness of the interaction techniques in a multi-monitorsetup, the hand tracking, head pose estimation and the face recognition were further evaluated using tests inspired by everyday tasks. The results of the evaluation and the discussion are presented in this paper.
A New Clinical HIFU System (Teleson II)
NASA Astrophysics Data System (ADS)
Ma, Yixin; Symonds-Tayler, Richard; Rivens, Ian H.; ter Haar, Gail R.
2007-05-01
Previous clinical trials with our first prototype HIFU system (Teleson I) for the treatment of liver tumors, demonstrated a major challenge to be treatment of those tumors located behind the ribs. We have designed a new multi-element transducer for rib sparing. Initial simulation and experimental results (using a single channel power amplifier) are very encouraging. A new clinical HIFU system which can drive the multi-element transducer and control each channel independently is being designed and constructed. This second version of a clinical prototype HIFU system consists of a 3D motorised gantry, a multi-channel signal generator, a multi-channel power amplifier, a user interface PC, an embedded controller and auxiliary circuits for real-time interleaving/synchronization control and a to-be-implemented safety monitoring and data logging unit. For multi-element transducers, each element can be individually switched on and off for rib sparing, and phase and amplitude modulated for potential phased array applications. The multi-channel power amplifier can be switched on/off very rapidly at required intervals to interleave with ultrasound B-Scan imaging for HIFU monitoring or radiation force elastography imaging via a dedicated interleaving/timing module. The gantry movement can also be synchronised with power amplifier on/off and phase/amplitude updating for lesion generation under a wide variety of conditions including single lesions, lesion arrays and lesions "tracks" created whilst translating the active transducer. Results from testing the system using excised tissue will be presented.
A practical indoor context-aware surveillance system with multi-Kinect sensors
NASA Astrophysics Data System (ADS)
Jia, Lili; You, Ying; Li, Tiezhu; Zhang, Shun
2014-11-01
In this paper we develop a novel practical application, which give scalable services to the end users when abnormal actives are happening. Architecture of the application has been presented consisting of network infrared cameras and a communication module. In this intelligent surveillance system we use Kinect sensors as the input cameras. Kinect is an infrared laser camera which its user can access the raw infrared sensor stream. We install several Kinect sensors in one room to track the human skeletons. Each sensor returns the body positions with 15 coordinates in its own coordinate system. We use calibration algorithms to calibrate all the body positions points into one unified coordinate system. With the body positions points, we can infer the surveillance context. Furthermore, the messages from the metadata index matrix will be sent to mobile phone through communication module. User will instantly be aware of an abnormal case happened in the room without having to check the website. In conclusion, theoretical analysis and experimental results in this paper show that the proposed system is reasonable and efficient. And the application method introduced in this paper is not only to discourage the criminals and assist police in the apprehension of suspects, but also can enabled the end-users monitor the indoor environments anywhere and anytime by their phones.
Effectiveness and usability of Scanning Wizard software: a tool for enhancing switch scanning.
Koester, Heidi Horstmann; Simpson, Richard C
2017-11-24
Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study evaluated Scanning Wizard's effectiveness and usability. Ten people who use switch scanning and ten practitioners used Scanning Wizard in the initial session. Usability was high, based on survey responses averaging over 4.5 out of 5, and qualitative feedback was very positive. Five switch users were able to complete the multi-week protocol, using settings on their own scanning system that were recommended from the Scanning Wizard session. Using these revised settings, text entry rates improved by an average of 71%, ranging from 29% to 172% improvement. Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate. Implications for Rehabilitation Some individuals with severe physical impairments use switch scanning for spoken and written communication. Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study demonstrated high usability of Scanning Wizard (with 10 switch userpractitioner teams) and increased text entry rate by an average of 71% (for five switch users). Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate.
NASA Astrophysics Data System (ADS)
Schaffer, B.; Kalverkamp, G.; Chaabane, M.; Biebl, E. M.
2012-09-01
We present a multi-user cooperative mobile transponder system which enables cars to localize pedestrians, bicyclists and other road users in order to improve traffic safety. The system operates at a center frequency of 5.768 GHz, offering the ability to test precision localization technology at frequencies close to the newly designated automotive safety related bands around 5.9 GHz. By carrying out a roundtrip time of flight measurement, the sensor can determine the distance from the onboard localization unit of a car to a road user who is equipped with an active transponder, employing the idea of a secondary radar and pulse compression. The onboard unit sends out a pseudo noise coded interrogation pulse, which is answered by one or more transponders after a short waiting time. Each transponder uses a different waiting time in order to allow for time division multiple access. We present the system setup as well as range measurement results, achieving an accuracy up to centimeters for the distance measurement and a range in the order of hundred meters. We also discuss the effect of clock drift and offset on distance accuracy for different waiting times and show how the system can be improved to further increase precision in a multiuser environment.
NASA Astrophysics Data System (ADS)
Zhang, Hao; Chen, Minghua; Parekh, Abhay; Ramchandran, Kannan
2011-09-01
We design a distributed multi-channel P2P Video-on-Demand (VoD) system using "plug-and-play" helpers. Helpers are heterogenous "micro-servers" with limited storage, bandwidth and number of users they can serve simultaneously. Our proposed system has the following salient features: (1) it jointly optimizes over helper-user connection topology, video storage distribution and transmission bandwidth allocation; (2) it minimizes server load, and is adaptable to varying supply and demand patterns across multiple video channels irrespective of video popularity; and (3) it is fully distributed and requires little or no maintenance overhead. The combinatorial nature of the problem and the system demand for distributed algorithms makes the problem uniquely challenging. By utilizing Lagrangian decomposition and Markov chain approximation based arguments, we address this challenge by designing two distributed algorithms running in tandem: a primal-dual storage and bandwidth allocation algorithm and a "soft-worst-neighbor-choking" topology-building algorithm. Our scheme provably converges to a near-optimal solution, and is easy to implement in practice. Packet-level simulation results show that the proposed scheme achieves minimum sever load under highly heterogeneous combinations of supply and demand patterns, and is robust to system dynamics of user/helper churn, user/helper asynchrony, and random delays in the network.
Multi-User Spaceport Update News Conference
2014-01-23
CAPE CANAVERAL, Fla. – Larry Price, Lockheed Martin Space Systems deputy program manager for NASA's Orion spacecraft, joins Sierra Nevada Corporation, or SNC, Space Systems, as the company announces the steps it will take to prepare for a November 2016 orbital flight of its Dream Chaser spacecraft from Florida’s Space Coast. The steps are considered substantial for SNC and important to plans by NASA and Space Florida for Kennedy Space Center’s transformation into a multi-user spaceport for both commercial and government customers. SNC said it plans to work with United Launch Alliance, or ULA, to launch the Dream Chaser spacecraft into orbit atop an Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station intends to land the winged spacecraft at Kennedy’s 3.5-mile long runway at the Shuttle Landing Facility lease office space at Exploration Park, right outside Kennedy’s gates and process the spacecraft in the high bay of the Operations and Checkout Building at Kennedy, with Lockheed Martin performing the work. Photo credit: NASA/Kim Shiflett
Collaborative Strategic Reading on Multi-Touch and Multi-User Digital Tabletop Displays
ERIC Educational Resources Information Center
Maslamani, Jaber Ali; Windeatt, Scott; Olivier, Patrick; Heslop, Phil; Kharrufa, Ahmed; Shearer, John; Balaam, Madeline
2012-01-01
This paper is part of a work-in-progress that reports on the design, development, and evaluation of a Digital Collaborative Strategic Reading (DCSR) application with regard to its effectiveness in improving English as a second language (ESL) reading comprehension. The DCSR application allows users to read collaboratively on multitouch and…
Educational MOO: Text-Based Virtual Reality for Learning in Community. ERIC Digest.
ERIC Educational Resources Information Center
Turbee, Lonnie
MOO stands for "Multi-user domain, Object-Oriented." Early multi-user domains, or "MUDs," began as net-based dungeons-and-dragons type games, but MOOs have evolved from these origins to become some of cyberspace's most fascinating and engaging online communities. MOOs are social environments in a text-based virtual reality…
Relating Narrative, Inquiry, and Inscriptions: Supporting Consequential Play
ERIC Educational Resources Information Center
Barab, Sasha A.; Sadler, Troy D.; Heiselt, Conan; Hickey, Daniel; Zuiker, Steven
2007-01-01
In this paper we describe our research using a multi-user virtual environment, "Quest Atlantis," to embed fourth grade students in an aquatic habitat simulation. Specifically targeted towards engaging students in a rich inquiry investigation, we layered a socio-scientific narrative and an interactive rule set into a multi-user virtual environment…
Preservice Teachers Experience Reading Response Pedagogy in a Multi-User Virtual Environment
ERIC Educational Resources Information Center
Dooley, Caitlin McMunn; Calandra, Brendan; Harmon, Stephen
2014-01-01
This qualitative case study describes how 18 preservice teachers learned to nurture literary meaning-making via activities based on Louise Rosenblatt's Reader Response Theory within a multi-user virtual environment (MUVE). Participants re-created and responded to scenes from selected works of children's literature in Second Life as a way to…
Interacting with a security system: The Argus user interface
DOE Office of Scientific and Technical Information (OSTI.GOV)
Behrin, E.; Davis, G.E.
1993-12-31
In the mid-1980s the Lawrence Livermore National Laboratory (LLNL) developed the Argus Security System. Key requirements were to eliminate the telephone as a verification device for opening and closing alarm stations and to allow need-to-know access through local enrollment at alarm stations. Resulting from these requirements was an LLNL-designed user interface called the Remote Access Panel (RAP). The Argus RAP interacts with Argus field processors to allow secure station mode changes and local station enrollment, provides user direction and response, and assists station maintenance personnel. It consists of a tamper-detecting housing containing a badge reader, a keypad with sight screen,more » special-purpose push buttons and a liquid-crystal display. This paper discusses Argus system concepts, RAP design, functional characteristics and its physical configurations. The paper also describes the RAP`s use in access-control booths, it`s integration with biometrics and its operation for multi-person-rule stations and compartmented facilities.« less
Multithreaded hybrid feature tracking for markerless augmented reality.
Lee, Taehee; Höllerer, Tobias
2009-01-01
We describe a novel markerless camera tracking approach and user interaction methodology for augmented reality (AR) on unprepared tabletop environments. We propose a real-time system architecture that combines two types of feature tracking. Distinctive image features of the scene are detected and tracked frame-to-frame by computing optical flow. In order to achieve real-time performance, multiple operations are processed in a synchronized multi-threaded manner: capturing a video frame, tracking features using optical flow, detecting distinctive invariant features, and rendering an output frame. We also introduce user interaction methodology for establishing a global coordinate system and for placing virtual objects in the AR environment by tracking a user's outstretched hand and estimating a camera pose relative to it. We evaluate the speed and accuracy of our hybrid feature tracking approach, and demonstrate a proof-of-concept application for enabling AR in unprepared tabletop environments, using bare hands for interaction.
Jia, Yun-Fang; Gao, Chun-Ying; He, Jia; Feng, Dao-Fu; Xing, Ke-Li; Wu, Ming; Liu, Yang; Cai, Wen-Sheng; Feng, Xi-Zeng
2012-08-21
Multi biomarkers' assays are of great significance in clinical diagnosis. A label-free multi tumor markers' parallel detection system was proposed based on a light addressable potentiometric sensor (LAPS). Arrayed LAPS chips with basic structure of Si(3)N(4)-SiO(2)-Si were prepared on silicon wafers, and the label-free parallel detection system for this component was developed with user friendly controlling interfaces. Then the l-3,4-dihydroxyphenyl-alanine (L-Dopa) hydrochloric solution was used to initiate the surface of LAPS. The L-Dopa immobilization state was investigated by the theoretical calculation. L-Dopa initiated LAPS' chip was biofunctionalized respectively by the antigens and antibodies of four tumor markers, α-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9) and Ferritin. Then unlabeled antibodies and antigens of these four biomarkers were detected by the proposed detection systems. Furthermore physical and measuring principles in this system were described, and qualitative understanding for experimental data were given. The measured response ranges were compared with their clinical cutoff values, and sensitivities were calculated by OriginLab. The results indicate that this bioinitiated LAPS based label-free detection system may offer a new choice for the realization of unlabeled multi tumor markers' clinical assay.
Lüneburg, Nicole; Siques, Patricia; Brito, Julio; De La Cruz, Juan José; León-Velarde, Fabiola; Hannemann, Juliane; Ibanez, Cristian; Böger, Rainer H
2017-09-01
Lüneburg, Nicole, Patricia Siques, Julio Brito, Juan José De La Cruz, Fabiola León-Velarde, Juliane Hannemann, Cristian Ibanez, and Rainer Böger. Long-term intermittent exposure to high altitude elevates asymmetric dimethylarginine in first exposed young adults. High Alt Med Biol. 18:226-233, 2017.-Hypoxia-induced dysregulation of pulmonary and cerebral circulation may be related to an impaired nitric oxide (NO) pathway. We investigated the effect of chronic intermittent hypobaric hypoxia (CIH) on metabolites of the NO pathway. We measured asymmetric and symmetric dimethylarginine (ADMA and SDMA) and monomethyl-L-arginine (L-NMMA) and assessed their associations with acclimatization in male draftees (n = 72) undergoing CIH shifts at altitude (3550 m) during 3 months. Sixteen Andean natives living at altitude (3675 m) (chronic hypobaric hypoxia [CH]) were included for comparison. In CIH, ADMA and L-NMMA plasma concentrations increased from 1.14 ± 0.04 to 1.95 ± 0.09 μmol/L (mean ± SE) and from 0.22 ± 0.07 to 0.39 ± 0.03 μmol/L, respectively, (p < 0.001 for both) after 3 months, whereas SDMA did not change. The concentrations of ADMA and L-NMMA were higher in CH (3.48 ± 0.07, 0.53 ± 0.08 μmol/L; p < 0.001) as compared with CIH. In both CIH and CH, ADMA correlated with hematocrit (r 2 = 0.07, p < 0.05; r 2 = 0.26; p < 0.01). In CIH, an association of ADMA levels with poor acclimatization status was observed. We conclude that the endogenous NO synthase inhibitors, ADMA and L-NMMA, are elevated in hypoxia. This may contribute to impaired NO production at altitude and may also be predictive of altitude-associated health impairment.
Siques, Patricia; Brito, Julio; De La Cruz, Juan José; León-Velarde, Fabiola; Hannemann, Juliane; Ibanez, Cristian; Böger, Rainer H.
2017-01-01
Abstract Lüneburg, Nicole, Patricia Siques, Julio Brito, Juan José De La Cruz, Fabiola León-Velarde, Juliane Hannemann, Cristian Ibanez, and Rainer Böger. Long-term intermittent exposure to high altitude elevates asymmetric dimethylarginine in first exposed young adults. High Alt Med Biol. 18:226–233, 2017.—Hypoxia-induced dysregulation of pulmonary and cerebral circulation may be related to an impaired nitric oxide (NO) pathway. We investigated the effect of chronic intermittent hypobaric hypoxia (CIH) on metabolites of the NO pathway. We measured asymmetric and symmetric dimethylarginine (ADMA and SDMA) and monomethyl-L-arginine (L-NMMA) and assessed their associations with acclimatization in male draftees (n = 72) undergoing CIH shifts at altitude (3550 m) during 3 months. Sixteen Andean natives living at altitude (3675 m) (chronic hypobaric hypoxia [CH]) were included for comparison. In CIH, ADMA and L-NMMA plasma concentrations increased from 1.14 ± 0.04 to 1.95 ± 0.09 μmol/L (mean ± SE) and from 0.22 ± 0.07 to 0.39 ± 0.03 μmol/L, respectively, (p < 0.001 for both) after 3 months, whereas SDMA did not change. The concentrations of ADMA and L-NMMA were higher in CH (3.48 ± 0.07, 0.53 ± 0.08 μmol/L; p < 0.001) as compared with CIH. In both CIH and CH, ADMA correlated with hematocrit (r2 = 0.07, p < 0.05; r2 = 0.26; p < 0.01). In CIH, an association of ADMA levels with poor acclimatization status was observed. We conclude that the endogenous NO synthase inhibitors, ADMA and L-NMMA, are elevated in hypoxia. This may contribute to impaired NO production at altitude and may also be predictive of altitude-associated health impairment. PMID:28453332
2014-11-05
usable simulations. This procedure was to be tested using real-world data collected from open-source venues. The final system would support rapid...assess social change. Construct is an agent-based dynamic-network simulation system design to allow the user to assess the spread of information and...protest or violence. Technical Challenges Addressed Re‐use: Most agent-based simulation ( ABM ) in use today are one-off. In contrast, we
1986-10-31
Reference Card Given to Participants) Cognoter Reference Select = LeftButton Menu = MiddleButton TitleBar menu for tool operations Item menu for item...collaborative tools and their uses, the Colab system and the Cognoter presentation tool were implemented and used for both real and posed idea organization...tasks. To test the system design and its effect on structured problem-solving, many early Colab/ Cognoter meetings were monitored and a series of
Secure multi-party communication with quantum key distribution managed by trusted authority
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, Richard John; Nordholt, Jane Elizabeth; Peterson, Charles Glen
Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD aremore » extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.« less
MGDS: Free, on-line, cutting-edge tools to enable the democratisation of geoscience data
NASA Astrophysics Data System (ADS)
Goodwillie, A. M.; Ryan, W. B.; O'Hara, S.; Ferrini, V.; Arko, R. A.; Coplan, J.; Chan, S.; Carbotte, S. M.; Nitsche, F. O.; Bonczkowski, J.; Morton, J. J.; Weissel, R.; Leung, A.
2010-12-01
The availability of user-friendly, effective cyber-information resources for accessing and manipulating geoscience data has grown rapidly in recent years. Based at Lamont-Doherty Earth Observatory the MGDS group has developed a number of free tools that have wide application across the geosciences for both educators and researchers. A simple web page (http://www.marine-geo.org/) allows users to search for and download many types of data by key word, geographical region, or published citation. The popular Create Maps and Grids function and the downloadable Google Earth-compatible KML files appeal to a wide user base. MGDS MediaBank galleries (http://media.marine-geo.org/) enable users to view and download compelling images that are purposefully selected for their educational value from NSF-funded field programs. GeoMapApp (http://www.geomapapp.org), a free map-based interactive tool that works on any machine, is increasingly being adopted across a broad suite of users from middle school students to university researchers. GeoMapApp allows users to plot, manipulate and present data in an intuitive geographical reference frame. GeoMapApp offers a convenient way to explore the wide range of built-in data sets, to quickly generate maps and images that aid visualisation and, when importing their own gridded and tabular data sets, to access the same rich built-in functionality. A user guide, short multi-media tutorials, and webinar are available on-line. The regularly-updated Global Multi-Resolution Topography (GMRT) Synthesis is used as the default GeoMapApp base map and is an increasingly popular means to rapidly create location maps. Additionally, the layer manager offers a fast way to overlay and compare multiple data sets and is augmented by the ability to alter layer transparency so that underlying layers become visible. Examples of GeoMapApp built-in data sets include high-resolution land topography and ocean floor bathymetry derived from satellite and multi-beam swath mapping systems - these can be profiled, shaded, and contoured; geo-registered geochemical sample analyses from the EarthChem database; plate boundary, earthquake and volcano catalogues; physical oceanography global and water column data; seafloor photos and Alvin dive video images; geological maps at various scales; and, high-quality coastline, lakes and rivers data. Customised data portals offer enhanced functionality for multi-channel seismic profiles, drill core logs, and earthquake animations. GeoMapApp is used in many MARGINS undergraduate-level off-the-shelf interactive learning activities called mini-lessons (http://serc.carleton.edu/margins/collection.html). Examples of educational applicability will be shown.
Blind information-theoretic multiuser detection algorithms for DS-CDMA and WCDMA downlink systems.
Waheed, Khuram; Salem, Fathi M
2005-07-01
Code division multiple access (CDMA) is based on the spread-spectrum technology and is a dominant air interface for 2.5G, 3G, and future wireless networks. For the CDMA downlink, the transmitted CDMA signals from the base station (BS) propagate through a noisy multipath fading communication channel before arriving at the receiver of the user equipment/mobile station (UE/MS). Classical CDMA single-user detection (SUD) algorithms implemented in the UE/MS receiver do not provide the required performance for modern high data-rate applications. In contrast, multi-user detection (MUD) approaches require a lot of a priori information not available to the UE/MS. In this paper, three promising adaptive Riemannian contra-variant (or natural) gradient based user detection approaches, capable of handling the highly dynamic wireless environments, are proposed. The first approach, blind multiuser detection (BMUD), is the process of simultaneously estimating multiple symbol sequences associated with all the users in the downlink of a CDMA communication system using only the received wireless data and without any knowledge of the user spreading codes. This approach is applicable to CDMA systems with relatively short spreading codes but becomes impractical for systems using long spreading codes. We also propose two other adaptive approaches, namely, RAKE -blind source recovery (RAKE-BSR) and RAKE-principal component analysis (RAKE-PCA) that fuse an adaptive stage into a standard RAKE receiver. This adaptation results in robust user detection algorithms with performance exceeding the linear minimum mean squared error (LMMSE) detectors for both Direct Sequence CDMA (DS-CDMA) and wide-band CDMA (WCDMA) systems under conditions of congestion, imprecise channel estimation and unmodeled multiple access interference (MAI).
A Global User-Driven Model for Tile Prefetching in Web Geographical Information Systems.
Pan, Shaoming; Chong, Yanwen; Zhang, Hang; Tan, Xicheng
2017-01-01
A web geographical information system is a typical service-intensive application. Tile prefetching and cache replacement can improve cache hit ratios by proactively fetching tiles from storage and replacing the appropriate tiles from the high-speed cache buffer without waiting for a client's requests, which reduces disk latency and improves system access performance. Most popular prefetching strategies consider only the relative tile popularities to predict which tile should be prefetched or consider only a single individual user's access behavior to determine which neighbor tiles need to be prefetched. Some studies show that comprehensively considering all users' access behaviors and all tiles' relationships in the prediction process can achieve more significant improvements. Thus, this work proposes a new global user-driven model for tile prefetching and cache replacement. First, based on all users' access behaviors, a type of expression method for tile correlation is designed and implemented. Then, a conditional prefetching probability can be computed based on the proposed correlation expression mode. Thus, some tiles to be prefetched can be found by computing and comparing the conditional prefetching probability from the uncached tiles set and, similarly, some replacement tiles can be found in the cache buffer according to multi-step prefetching. Finally, some experiments are provided comparing the proposed model with other global user-driven models, other single user-driven models, and other client-side prefetching strategies. The results show that the proposed model can achieve a prefetching hit rate in approximately 10.6% ~ 110.5% higher than the compared methods.
Johnson, Ari; Goss, Adeline; Beckerman, Jessica; Castro, Arachu
2012-11-01
About 20 years after initial calls for the introduction of user fees in health systems in sub-Saharan Africa, a growing coalition is advocating for their removal. Several African countries have abolished user fees for health care for some or all of their citizens. However, fee-for-service health care delivery remains a primary health care funding model in many countries in sub-Saharan Africa. Although the impact of user fees on utilization of health services and household finances has been studied extensively, further research is needed to characterize the multi-faceted health and social problems associated with charging user fees. This ethnographic study aims to identify consequences of user fees on gender inequality, food insecurity, and household decision-making for a group of women living in poverty. Ethnographic life history interviews were conducted with 24 women in Yirimadjo, Mali in 2007. Purposive sampling selected participants across a broad socio-economic spectrum. Semi-structured interviews addressed participants' past medical history, socio-economic status, social and family history, and access to health care. Interview transcripts were coded using the guiding analytical framework of structural violence. Interviews revealed that user fees for health care not only decreased utilization of health services, but also resulted in delayed presentation for care, incomplete or inadequate care, compromised food security and household financial security, and reduced agency for women in health care decision making. The effects of user fees were amplified by conditions of poverty, as well as gender and health inequality; user fees in turn reinforced the inequalities created by those very conditions. The qualitative data reveal multi-faceted health and socioeconomic effects of user fees, and illustrate that user fees for health care may impact quality of care, health outcomes, food insecurity, and gender inequality, in addition to impacting health care utilization and household finances. As many countries consider user fee abolition policies, these findings indicate the need to create a broader evaluation framework-one that can measure the health and socioeconomic impacts of user fee polices and of their removal. Copyright © 2012 Elsevier Ltd. All rights reserved.
Secure Biometric Multi-Logon System Based on Current Authentication Technologies
NASA Astrophysics Data System (ADS)
Tait, Bobby L.
The need for accurate authentication in the current IT world is of utmost importance. Users rely on current IT technologies to facilitate in day to day interactions with nearly all environments. Strong authentication technologies like the various biometric technologies have been in existence for many years. Many of these technologies, for instance fingerprint biometrics, have reached maturity. However, passwords and pins are still the most commonly used authentication mechanisms at this stage. An average user has to be authenticated in various situations during daily interaction with his or her environment, by means of a pin or a password. This results in many different passwords and pins that the user has to remember. The user will eventually either start documenting these passwords and pins, or often, simply use the same password and pin for all authentication situations.
Securely and Flexibly Sharing a Biomedical Data Management System
Wang, Fusheng; Hussels, Phillip; Liu, Peiya
2011-01-01
Biomedical database systems need not only to address the issues of managing complex data, but also to provide data security and access control to the system. These include not only system level security, but also instance level access control such as access of documents, schemas, or aggregation of information. The latter is becoming more important as multiple users can share a single scientific data management system to conduct their research, while data have to be protected before they are published or IP-protected. This problem is challenging as users’ needs for data security vary dramatically from one application to another, in terms of who to share with, what resources to be shared, and at what access level. We develop a comprehensive data access framework for a biomedical data management system SciPort. SciPort provides fine-grained multi-level space based access control of resources at not only object level (documents and schemas), but also space level (resources set aggregated in a hierarchy way). Furthermore, to simplify the management of users and privileges, customizable role-based user model is developed. The access control is implemented efficiently by integrating access privileges into the backend XML database, thus efficient queries are supported. The secure access approach we take makes it possible for multiple users to share the same biomedical data management system with flexible access management and high data security. PMID:21625285
Multi-Mission System Analysis for Planetary Entry (M-SAPE) Version 1
NASA Technical Reports Server (NTRS)
Samareh, Jamshid; Glaab, Louis; Winski, Richard G.; Maddock, Robert W.; Emmett, Anjie L.; Munk, Michelle M.; Agrawal, Parul; Sepka, Steve; Aliaga, Jose; Zarchi, Kerry;
2014-01-01
This report describes an integrated system for Multi-mission System Analysis for Planetary Entry (M-SAPE). The system in its current form is capable of performing system analysis and design for an Earth entry vehicle suitable for sample return missions. The system includes geometry, mass sizing, impact analysis, structural analysis, flight mechanics, TPS, and a web portal for user access. The report includes details of M-SAPE modules and provides sample results. Current M-SAPE vehicle design concept is based on Mars sample return (MSR) Earth entry vehicle design, which is driven by minimizing risk associated with sample containment (no parachute and passive aerodynamic stability). By M-SAPE exploiting a common design concept, any sample return mission, particularly MSR, will benefit from significant risk and development cost reductions. The design provides a platform by which technologies and design elements can be evaluated rapidly prior to any costly investment commitment.
Crowe, A S; Booty, W G
1995-05-01
A multi-level pesticide assessment methodology has been developed to permit regulatory personnel to undertake a variety of assessments on the potential for pesticide used in agricultural areas to contaminate the groundwater regime at an increasingly detailed geographical scale of investigation. A multi-level approach accounts for a variety of assessment objectives and detail required in the assessment, the restrictions on the availability and accuracy of data, the time available to undertake the assessment, and the expertise of the decision maker. The level 1: regional scale is designed to prioritize districts having a potentially high risk for groundwater contamination from the application of a specific pesticide for a particular crop. The level 2: local scale is used to identify critical areas for groundwater contamination, at a soil polygon scale, within a district. A level 3: soil profile scale allows the user to evaluate specific factors influencing pesticide leaching and persistence, and to determine the extent and timing of leaching, through the simulation of the migration of a pesticide within a soil profile. Because of the scale of investigation, limited amount of data required, and qualitative nature of the assessment results, the level 1 and level 2 assessment are designed primarily for quick and broad guidance related to management practices. A level 3 assessment is more complex, requires considerably more data and expertise on the part of the user, and hence is designed to verify the potential for contamination identified during the level 1 or 2 assessment. The system combines environmental modelling, geographical information systems, extensive databases, data management systems, expert systems, and pesticide assessment models, to form an environmental information system for assessing the potential for pesticides to contaminate groundwater.
Multi-axis control based on movement control cards in NC systems
NASA Astrophysics Data System (ADS)
Jiang, Tingbiao; Wei, Yunquan
2005-12-01
Today most movement control cards need special control software of topper computers and are only suitable for fixed-axis controls. Consequently, the number of axes which can be controlled is limited. Advanced manufacture technology develops at a very high speed, and that development brings forth. New requirements for movement control in mechanisms and electronics. This paper introduces products of the 5th generation of movement control cards, PMAC 2A-PC/104, made by the Delta Tau Company in the USA. Based on an analysis of PMAC 2A-PC/104, this paper first describes two aspects relevant to the hardware structure of movement control cards and the interrelated software of the topper computers. Then, two methods are presented for solving these problems. The first method is to set limit switches on the movement control cards; all of them can be used to control each moving axis. The second method is to program applied software with existing programming language (for example, VC ++, Visual Basic, Delphi, and so forth). This program is much easier to operate and expand by its users. By using a limit switch, users can choose different axes in movement control cards. Also, users can change parts of the parameters in the control software of topper computers to realize different control axes. Combining these 2 methods proves to be convenient for realizing multi-axis control in numerical control systems.
The Effect of Personality on Collaborative Task Performance and Interaction
NASA Astrophysics Data System (ADS)
Givney, Sinéad Mc; Smeaton, Alan F.; Lee, Hyowon
Collocated, multi-user technologies, which support group-work are becoming increasingly popular. Examples include MERL’s Diamondtouch and Microsoft’s Surface, both of which have evolved from research prototypes to commercial products. Many applications have been developed for such technologies which support the work and entertainment needs of small groups of people. None of these applications however, have been studied in terms of the interactions and performances of their users with regards to their personality. In this paper, we address this research gap by conducting a series of user studies involving dyads working on a number of multi-user applications on the DiamondTouch tabletop device.
Engineering of Data Acquiring Mobile Software and Sustainable End-User Applications
NASA Technical Reports Server (NTRS)
Smith, Benton T.
2013-01-01
The criteria for which data acquiring software and its supporting infrastructure should be designed should take the following two points into account: the reusability and organization of stored online and remote data and content, and an assessment on whether abandoning a platform optimized design in favor for a multi-platform solution significantly reduces the performance of an end-user application. Furthermore, in-house applications that control or process instrument acquired data for end-users should be designed with a communication and control interface such that the application's modules can be reused as plug-in modular components in greater software systems. The application of the above mentioned is applied using two loosely related projects: a mobile application, and a website containing live and simulated data. For the intelligent devices mobile application AIDM, the end-user interface have a platform and data type optimized design, while the database and back-end applications store this information in an organized manner and manage access to that data to only to authorized user end application(s). Finally, the content for the website was derived from a database such that the content can be included and uniform to all applications accessing the content. With these projects being ongoing, I have concluded from my research that the applicable methods presented are feasible for both projects, and that a multi-platform design for the mobile application only marginally drop the performance of the mobile application.
A Multi-User Virtual Environment for Building and Assessing Higher Order Inquiry Skills in Science
ERIC Educational Resources Information Center
Ketelhut, Diane Jass; Nelson, Brian C.; Clarke, Jody; Dede, Chris
2010-01-01
This study investigated novel pedagogies for helping teachers infuse inquiry into a standards-based science curriculum. Using a multi-user virtual environment (MUVE) as a pedagogical vehicle, teams of middle-school students collaboratively solved problems around disease in a virtual town called River City. The students interacted with "avatars" of…
Civic Participation among Seventh-Grade Social Studies Students in Multi-User Virtual Environments
ERIC Educational Resources Information Center
Zieger, Laura; Farber, Matthew
2012-01-01
Technological advances on the Internet now enable students to develop participation skills in virtual worlds. Similar to controlling a character in a video game, multi-user virtual environments, or MUVEs, allow participants to interact with others in synchronous, online settings. The authors of this study created a link between MUVEs and…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hedstrom, Gerald; Beck, Bret; Mattoon, Caleb
2016-10-01
Merced performs a multi-dimensional integral tl generate so-called 'transfer matrices' for use in deterministic radiation transport applications. It produces transfer matrices on the user-defind energy grid. The angular dependence of outgoing products is captured in a Legendre expansion, up to a user-specified maximun Legendre order. Merced calculations can use multi-threading for enhanced performance on a single compute node.
16 CFR 1212.3 - Requirements for multi-purpose lighters.
Code of Federal Regulations, 2010 CFR
2010-01-01
... reset when or before the user lets go of the lighter. (5) The child-resistant mechanism of a multi... operation can occur; (ii) Have a manual mechanism for turning off the flame when the hands-free function is used; and either (iii) Automatically reset when or before the user lets go of the lighter when the...
ERIC Educational Resources Information Center
Oh, Seungjae; So, Hyo-Jeong; Gaydos, Matthew
2018-01-01
The goal for this research is to articulate and test a new hybrid Augmented Reality (AR) environment for conceptual understanding. From the theoretical lens of embodied interaction, we have designed a multi-user participatory simulation called ARfract where visitors in a science museum can learn about complex scientific concepts on the refraction…
ERIC Educational Resources Information Center
Sohn, Johannah Eve
2014-01-01
This descriptive case study explores the implementation of a multi-user virtual environment (MUVE) in a Jewish supplemental school setting. The research was conducted to present the recollections and reflections of three constituent populations of a new technology exploring constructivist education in the context of supplemental and online…
ERIC Educational Resources Information Center
Nelson, Brian C.; Erlandson, Benjamin E.
2008-01-01
In this paper, we explore how the application of multimedia design principles may inform the development of educational multi-user virtual environments (MUVEs). We look at design principles that have been shown to help learners manage cognitive load within multimedia environments and conduct a conjectural analysis of the extent to which such…
Socialisation for Learning at a Distance in a 3-D Multi-User Virtual Environment
ERIC Educational Resources Information Center
Edirisingha, Palitha; Nie, Ming; Pluciennik, Mark; Young, Ruth
2009-01-01
This paper reports findings of a pilot study that examined the pedagogical potential of "Second Life" (SL), a popular three-dimensional multi-user virtual environment (3-D MUVE) developed by the Linden Lab. The study is part of a 1-year research and development project titled "Modelling of Secondlife Environments"…
Zhai, Peng-Wang; Hu, Yongxiang; Trepte, Charles R; Lucker, Patricia L
2009-02-16
A vector radiative transfer model has been developed for coupled atmosphere and ocean systems based on the Successive Order of Scattering (SOS) Method. The emphasis of this study is to make the model easy-to-use and computationally efficient. This model provides the full Stokes vector at arbitrary locations which can be conveniently specified by users. The model is capable of tracking and labeling different sources of the photons that are measured, e.g. water leaving radiances and reflected sky lights. This model also has the capability to separate florescence from multi-scattered sunlight. The delta - fit technique has been adopted to reduce computational time associated with the strongly forward-peaked scattering phase matrices. The exponential - linear approximation has been used to reduce the number of discretized vertical layers while maintaining the accuracy. This model is developed to serve the remote sensing community in harvesting physical parameters from multi-platform, multi-sensor measurements that target different components of the atmosphere-oceanic system.
Earthdata 3.0: A Unified Experience and Platform for Earth Science Discovery
NASA Astrophysics Data System (ADS)
Plofchan, P.; McLaughlin, B. D.
2015-12-01
NASA's EOSDIS (Earth Observing System Data and Information System) as a multitude of websites and applications focused on serving the Earth Science community's extensive data needs. With no central user interface, theme, or mechanism for accessing that data, interrelated systems are confusing and potentially disruptive in users' searches for EOSDIS data holdings. In an effort to bring consistency across these systems, an effort was undertaken to develop Earthdata 3.0: a complete information architecture overhaul of the Earthdata website, a significant update to the Earthdata user experience and user interface, and an increased focus on searching across EOSDIS data holdings, including those housed and made available through DAAC websites. As part of this effort, and in a desire to unify the user experience across related websites, the Earthdata User Interface (EUI) was developed. The EUI is a collection of responsive design components and layouts geared toward creating websites and applications within the Earthdata ecosystem. Each component and layout has been designed specifically for Earth science-related projects which eliminates some of the complexities of building a website or application from the ground up. Its adoption will ensure both consistent markup and a unified look and feel for end users, thereby increasing usability and accessibility. Additionally, through the user of a Google Search Appliance, custom Clojure code, and in cooperation with DAACs, Earthdata 3.0 presents a variety of search results upon a user's keyword(s) entry. These results are not just textual links, but also direct links to downloadable datasets, visualizations of datasets and collections of data, and related articles and videos for further research. The end result of the development of the EUI and the enhanced multi-response type search is a consistent and usable platform for Earth scientists and users to navigate and locate data to further their research.
MultiElec: A MATLAB Based Application for MEA Data Analysis.
Georgiadis, Vassilis; Stephanou, Anastasis; Townsend, Paul A; Jackson, Thomas R
2015-01-01
We present MultiElec, an open source MATLAB based application for data analysis of microelectrode array (MEA) recordings. MultiElec displays an extremely user-friendly graphic user interface (GUI) that allows the simultaneous display and analysis of voltage traces for 60 electrodes and includes functions for activation-time determination, the production of activation-time heat maps with activation time and isoline display. Furthermore, local conduction velocities are semi-automatically calculated along with their corresponding vector plots. MultiElec allows ad hoc signal suppression, enabling the user to easily and efficiently handle signal artefacts and for incomplete data sets to be analysed. Voltage traces and heat maps can be simply exported for figure production and presentation. In addition, our platform is able to produce 3D videos of signal progression over all 60 electrodes. Functions are controlled entirely by a single GUI with no need for command line input or any understanding of MATLAB code. MultiElec is open source under the terms of the GNU General Public License as published by the Free Software Foundation, version 3. Both the program and source code are available to download from http://www.cancer.manchester.ac.uk/MultiElec/.
NASA Technical Reports Server (NTRS)
McGuire, Robert E.; Candey, Robert M.; Bilitza, D.
2006-01-01
The Sun-Earth Connection Active Archive (SECAA) project of NASA's Space Physics Data Facility operates a range of unique and heavily used multi-mission data services in support of the large-scale science objectives of the Great Observatory, including services such as CDAWeb, the CDAWeb Plus client, SSCWeb, OMNIweb and the CDF data format. In developing and operating these services, we have encountered and continue to struggle with a wide range of issues such as balancing scope and functionality with simplicity and ease of use, understanding the effectiveness of our choices and identifying areas most important for further improvement. In this paper, we will review our key services and then discuss some of our observations and new approaches to understanding and meeting user data service requirements. Some observations are obvious but may still have substantial implications; e.g. functionality without information content is of little user interest, which has led to our recent emphasis on development of web services interfaces, so the content and functionality we already serve is readily and fully available as a building block for new services. Some observations require careful design and tradeoffs; e.g. users will complain when they are offered interfaces with limited options but users are also easily intimidated and become lost when offered extensive options for customization. Some observations remain highly challenging; e.g. a comprehensive multi-mission, multi-source view of all data and services available easily produces a daunting list, but a more selective view can easily lead users to overlook available and relevant data. It is often difficult to obtain and meaningfully interpret measures of true productive usage and overall user satisfaction, even with a variety of techniques including statistics, citations, case studies, user feedback and advisory committees. Most of these issues will apply to and may even be more acute for distributed implementation architectures.
Yerramilli, Murthy; Farace, Giosi; Quinn, John; Yerramilli, Maha
2016-11-01
Chronic kidney disease (CKD) and acute kidney injury (AKI) are interconnected and the presence of one is a risk for the other. CKD is an important predictor of AKI after exposure to nephrotoxic drugs or major surgery, whereas persistent or repetitive injury could result in the progression of CKD. This brings new perspectives to the diagnosis and monitoring of kidney diseases highlighting the need for a panel of kidney-specific biomarkers that reflect functional as well as structural damage and recovery, predict potential risk and provide prognosis. This article discusses the kidney-specific biomarkers, symmetric dimethylarginine (SDMA), clusterin, cystatin B, and inosine. Copyright © 2016 Elsevier Inc. All rights reserved.
Health Care Robotics: A Progress Report
NASA Technical Reports Server (NTRS)
Fiorini, Paolo; Ali, Khaled; Seraji, Homayoun
1997-01-01
This paper describes the approach followed in the design of a service robot for health care applications. Under the auspices of the NASA Technology Transfer program, a partnership was established between JPL and RWI, a manufacturer of mobile robots, to design and evaluate a mobile robot for health care assistance to the elderly and the handicapped. The main emphasis of the first phase of the project is on the development on a multi-modal operator interface and its evaluation by health care professionals and users. This paper describes the architecture of the system, the evaluation method used, and some preliminary results of the user evaluation.
The ACE multi-user web-based Robotic Observatory Control System
NASA Astrophysics Data System (ADS)
Mack, P.
2003-05-01
We have developed an observatory control system that can be operated in interactive, remote or robotic modes. In interactive and remote mode the observer typically acquires the first object then creates a script through a window interface to complete observations for the rest of the night. The system closes early in the event of bad weather. In robotic mode observations are submitted ahead of time through a web-based interface. We present observations made with a 1.0-m telescope using these methods.
A Data-Based Approach to Discovering Multi-Topic Influential Leaders.
Tang, Xing; Miao, Qiguang; Yu, Shangshang; Quan, Yining
2016-01-01
Recently, increasing numbers of users have adopted microblogging services as their main information source. However, most of them find themselves drowning in the millions of posts produced by other users every day. To cope with this, identifying a set of the most influential people is paramount. Moreover, finding a set of related influential users to expand the coverage of one particular topic is required in real world scenarios. Most of the existing algorithms in this area focus on topology-related methods such as PageRank. These methods mine link structures to find the expected influential rank of users. However, because they ignore the interaction data, these methods turn out to be less effective in social networks. In reality, a variety of topics exist within the information diffusing through the network. Because they have different interests, users play different roles in the diffusion of information related to different topics. As a result, distinguishing influential leaders according to different topics is also worthy of research. In this paper, we propose a multi-topic influence diffusion model (MTID) based on traces acquired from historic information. We decompose the influential scores of users into two parts: the direct influence determined by information propagation along the link structure and indirect influence that extends beyond the restrictions of direct follower relationships. To model the network from a multi-topical viewpoint, we introduce topic pools, each of which represents a particular topic information source. Then, we extract the topic distributions from the traces of tweets, determining the influence propagation probability and content generation probability. In the network, we adopt multiple ground nodes representing topic pools to connect every user through bidirectional links. Based on this multi-topical view of the network, we further introduce the topic-dependent rank (TD-Rank) algorithm to identify the multi-topic influential users. Our algorithm not only effectively overcomes the shortages of PageRank but also effectively produces a measure of topic-related rank. Extensive experiments on a Weibo dataset show that our model is both effective and robust.
A Data-Based Approach to Discovering Multi-Topic Influential Leaders
Tang, Xing; Miao, Qiguang; Yu, Shangshang; Quan, Yining
2016-01-01
Recently, increasing numbers of users have adopted microblogging services as their main information source. However, most of them find themselves drowning in the millions of posts produced by other users every day. To cope with this, identifying a set of the most influential people is paramount. Moreover, finding a set of related influential users to expand the coverage of one particular topic is required in real world scenarios. Most of the existing algorithms in this area focus on topology-related methods such as PageRank. These methods mine link structures to find the expected influential rank of users. However, because they ignore the interaction data, these methods turn out to be less effective in social networks. In reality, a variety of topics exist within the information diffusing through the network. Because they have different interests, users play different roles in the diffusion of information related to different topics. As a result, distinguishing influential leaders according to different topics is also worthy of research. In this paper, we propose a multi-topic influence diffusion model (MTID) based on traces acquired from historic information. We decompose the influential scores of users into two parts: the direct influence determined by information propagation along the link structure and indirect influence that extends beyond the restrictions of direct follower relationships. To model the network from a multi-topical viewpoint, we introduce topic pools, each of which represents a particular topic information source. Then, we extract the topic distributions from the traces of tweets, determining the influence propagation probability and content generation probability. In the network, we adopt multiple ground nodes representing topic pools to connect every user through bidirectional links. Based on this multi-topical view of the network, we further introduce the topic-dependent rank (TD-Rank) algorithm to identify the multi-topic influential users. Our algorithm not only effectively overcomes the shortages of PageRank but also effectively produces a measure of topic-related rank. Extensive experiments on a Weibo dataset show that our model is both effective and robust. PMID:27415429
ERIC Educational Resources Information Center
Badilescu-Buga, Emil
2012-01-01
Learning Activity Management System (LAMS) has been trialled and used by users from many countries around the globe, but despite the positive attitude towards its potential benefits to pedagogical processes its adoption in practice has been uneven, reflecting how difficult it is to make a new technology based concept an integral part of the…
MURI: Impact of Oceanographic Variability on Acoustic Communications
2011-09-01
multiplexing ( OFDM ), multiple- input/multiple-output ( MIMO ) transmissions, and multi-user single-input/multiple-output (SIMO) communications. Lastly... MIMO - OFDM communications: Receiver design for Doppler distorted underwater acoustic channels,” Proc. Asilomar Conf. on Signals, Systems, and... MIMO ) will be of particular interest. Validating experimental data will be obtained during the ONR acoustic communications experiment in summer 2008
ERIC Educational Resources Information Center
Mandel, Lauren Heather
2012-01-01
Wayfinding is the method by which humans orient and navigate in space, and particularly in built environments such as cities and complex buildings, including public libraries. In order to wayfind successfully in the built environment, humans need information provided by wayfinding systems and tools, for instance architectural cues, signs, and…
Design, Fabrication, and Characterization of a Microelectromechanical Directional Microphone
2011-06-01
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES...Figure 5.2 SOIC packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 5.3 Laboratory setup...Mean Squared SOC System-On-Chip SOIC Small Outline Integrated Circuit SOIMUMPS Silicon-On-Insulator Multi-User MEMS Process SPL Sound Pressure Level
Polyphonic Music Information Retrieval Based on Multi-Label Cascade Classification System
ERIC Educational Resources Information Center
Jiang, Wenxin
2009-01-01
Recognition and separation of sounds played by various instruments is very useful in labeling audio files with semantic information. This is a non-trivial task requiring sound analysis, but the results can aid automatic indexing and browsing music data when searching for melodies played by user specified instruments. Melody match based on pitch…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cowell, Andrew J.; Haack, Jereme N.; McColgin, Dave W.
2006-06-08
This research is aimed at understanding the dynamics of collaborative multi-party discourse across multiple communication modalities. Before we can truly make sig-nificant strides in devising collaborative communication systems, there is a need to understand how typical users utilize com-putationally supported communications mechanisms such as email, instant mes-saging, video conferencing, chat rooms, etc., both singularly and in conjunction with traditional means of communication such as face-to-face meetings, telephone calls and postal mail. Attempting to un-derstand an individual’s communications profile with access to only a single modal-ity is challenging at best and often futile. Here, we discuss the development of RACE –more » Retrospective Analysis of Com-munications Events – a test-bed prototype to investigate issues relating to multi-modal multi-party discourse.« less
Multi-Temporal Analysis of Landsat Imagery for Bathymetry.
1983-05-01
this data set, typical results obtained when these data were used to implement proposed procedures, an interpretation of these analyses, and based...warping, etc.) have been carried out * as described in section 3.4 and the DIPS operator manuals . For each date * the best available parameter...1982. 5. Digital Image Processing System User’s Manual DBA Systems, Inc., Under Contract DMA800-78-C-0101, 8 November 1979. 6. Naylor, L.D. Status of
Pad 39B Flame Trench Upgrades and modifications
2016-03-03
Upgrades and modifications continue to the flame trench at Launch Pad 39B at NASA’s Kennedy Space Center in Florida. Pad B is being refurbished to support the launch of NASA’s Space Launch System rocket. The Ground Systems Development and Operations (GSDO) Program at Kennedy is helping transform the space center into a multi-user spaceport and prepare for Exploration Mission-1, deep-space missions, and the journey to Mars.
Large Scale Document Inversion using a Multi-threaded Computing System
Jung, Sungbo; Chang, Dar-Jen; Park, Juw Won
2018-01-01
Current microprocessor architecture is moving towards multi-core/multi-threaded systems. This trend has led to a surge of interest in using multi-threaded computing devices, such as the Graphics Processing Unit (GPU), for general purpose computing. We can utilize the GPU in computation as a massive parallel coprocessor because the GPU consists of multiple cores. The GPU is also an affordable, attractive, and user-programmable commodity. Nowadays a lot of information has been flooded into the digital domain around the world. Huge volume of data, such as digital libraries, social networking services, e-commerce product data, and reviews, etc., is produced or collected every moment with dramatic growth in size. Although the inverted index is a useful data structure that can be used for full text searches or document retrieval, a large number of documents will require a tremendous amount of time to create the index. The performance of document inversion can be improved by multi-thread or multi-core GPU. Our approach is to implement a linear-time, hash-based, single program multiple data (SPMD), document inversion algorithm on the NVIDIA GPU/CUDA programming platform utilizing the huge computational power of the GPU, to develop high performance solutions for document indexing. Our proposed parallel document inversion system shows 2-3 times faster performance than a sequential system on two different test datasets from PubMed abstract and e-commerce product reviews. CCS Concepts •Information systems➝Information retrieval • Computing methodologies➝Massively parallel and high-performance simulations. PMID:29861701
Large Scale Document Inversion using a Multi-threaded Computing System.
Jung, Sungbo; Chang, Dar-Jen; Park, Juw Won
2017-06-01
Current microprocessor architecture is moving towards multi-core/multi-threaded systems. This trend has led to a surge of interest in using multi-threaded computing devices, such as the Graphics Processing Unit (GPU), for general purpose computing. We can utilize the GPU in computation as a massive parallel coprocessor because the GPU consists of multiple cores. The GPU is also an affordable, attractive, and user-programmable commodity. Nowadays a lot of information has been flooded into the digital domain around the world. Huge volume of data, such as digital libraries, social networking services, e-commerce product data, and reviews, etc., is produced or collected every moment with dramatic growth in size. Although the inverted index is a useful data structure that can be used for full text searches or document retrieval, a large number of documents will require a tremendous amount of time to create the index. The performance of document inversion can be improved by multi-thread or multi-core GPU. Our approach is to implement a linear-time, hash-based, single program multiple data (SPMD), document inversion algorithm on the NVIDIA GPU/CUDA programming platform utilizing the huge computational power of the GPU, to develop high performance solutions for document indexing. Our proposed parallel document inversion system shows 2-3 times faster performance than a sequential system on two different test datasets from PubMed abstract and e-commerce product reviews. •Information systems➝Information retrieval • Computing methodologies➝Massively parallel and high-performance simulations.
Losier, Y; Englehart, K; Hudgins, B
2007-01-01
The integration of multiple input sources within a control strategy for powered upper limb prostheses could provide smoother, more intuitive multi-joint reaching movements based on the user's intended motion. The work presented in this paper presents the results of using myoelectric signals (MES) of the shoulder area in combination with the position of the shoulder as input sources to multiple linear discriminant analysis classifiers. Such an approach may provide users with control signals capable of controlling three degrees of freedom (DOF). This work is another important step in the development of hybrid systems that will enable simultaneous control of multiple degrees of freedom used for reaching tasks in a prosthetic limb.
A system for tracking and recognizing pedestrian faces using a network of loosely coupled cameras
NASA Astrophysics Data System (ADS)
Gagnon, L.; Laliberté, F.; Foucher, S.; Branzan Albu, A.; Laurendeau, D.
2006-05-01
A face recognition module has been developed for an intelligent multi-camera video surveillance system. The module can recognize a pedestrian face in terms of six basic emotions and the neutral state. Face and facial features detection (eyes, nasal root, nose and mouth) are first performed using cascades of boosted classifiers. These features are used to normalize the pose and dimension of the face image. Gabor filters are then sampled on a regular grid covering the face image to build a facial feature vector that feeds a nearest neighbor classifier with a cosine distance similarity measure for facial expression interpretation and face model construction. A graphical user interface allows the user to adjust the module parameters.
NASA Astrophysics Data System (ADS)
Ikeda, Takeshi; Kawamoto, Mitsuru; Sashima, Akio; Suzuki, Keiji; Kurumatani, Koichi
In the field of the ubiquitous computing, positioning systems which can provide users' location information have paid attention as an important technical element which can be applied to various services, for example, indoor navigation services, evacuation services, market research services, guidance services, and so on. A lot of researchers have proposed various outdoor and indoor positioning systems. In this paper, we deal with indoor positioning systems. Many conventional indoor positioning systems use expensive infrastructures, because the propagated times of radio waves are used to measure users' positions with high accuracy. In this paper, we propose an indoor autonomous positioning system using radio signal strengths (RSSs) based on ISM band communications. In order to estimate users' positions, the proposed system utilizes a particle filter that is one of the Monte Carlo methods. Because the RSS information is used in the proposed system, the equipments configuring the system are not expensive compared with the conventional indoor positioning systems and it can be installed easily. Moreover, because the particle filter is used to estimate user's position, even if the RSS fluctuates due to, for example, multi-paths, the system can carry out position estimation robustly. We install the proposed system in one floor of a building and carry out some experiments in order to verify the validity of the proposed system. As a result, we confirmed that the average of the estimation errors of the proposed system was about 1.8 m, where the result is enough accuracy for achieving the services mentioned above.
Multi-Resolution Climate Ensemble Parameter Analysis with Nested Parallel Coordinates Plots.
Wang, Junpeng; Liu, Xiaotong; Shen, Han-Wei; Lin, Guang
2017-01-01
Due to the uncertain nature of weather prediction, climate simulations are usually performed multiple times with different spatial resolutions. The outputs of simulations are multi-resolution spatial temporal ensembles. Each simulation run uses a unique set of values for multiple convective parameters. Distinct parameter settings from different simulation runs in different resolutions constitute a multi-resolution high-dimensional parameter space. Understanding the correlation between the different convective parameters, and establishing a connection between the parameter settings and the ensemble outputs are crucial to domain scientists. The multi-resolution high-dimensional parameter space, however, presents a unique challenge to the existing correlation visualization techniques. We present Nested Parallel Coordinates Plot (NPCP), a new type of parallel coordinates plots that enables visualization of intra-resolution and inter-resolution parameter correlations. With flexible user control, NPCP integrates superimposition, juxtaposition and explicit encodings in a single view for comparative data visualization and analysis. We develop an integrated visual analytics system to help domain scientists understand the connection between multi-resolution convective parameters and the large spatial temporal ensembles. Our system presents intricate climate ensembles with a comprehensive overview and on-demand geographic details. We demonstrate NPCP, along with the climate ensemble visualization system, based on real-world use-cases from our collaborators in computational and predictive science.
Using CellML with OpenCMISS to Simulate Multi-Scale Physiology
Nickerson, David P.; Ladd, David; Hussan, Jagir R.; Safaei, Soroush; Suresh, Vinod; Hunter, Peter J.; Bradley, Christopher P.
2014-01-01
OpenCMISS is an open-source modeling environment aimed, in particular, at the solution of bioengineering problems. OpenCMISS consists of two main parts: a computational library (OpenCMISS-Iron) and a field manipulation and visualization library (OpenCMISS-Zinc). OpenCMISS is designed for the solution of coupled multi-scale, multi-physics problems in a general-purpose parallel environment. CellML is an XML format designed to encode biophysically based systems of ordinary differential equations and both linear and non-linear algebraic equations. A primary design goal of CellML is to allow mathematical models to be encoded in a modular and reusable format to aid reproducibility and interoperability of modeling studies. In OpenCMISS, we make use of CellML models to enable users to configure various aspects of their multi-scale physiological models. This avoids the need for users to be familiar with the OpenCMISS internal code in order to perform customized computational experiments. Examples of this are: cellular electrophysiology models embedded in tissue electrical propagation models; material constitutive relationships for mechanical growth and deformation simulations; time-varying boundary conditions for various problem domains; and fluid constitutive relationships and lumped-parameter models. In this paper, we provide implementation details describing how CellML models are integrated into multi-scale physiological models in OpenCMISS. The external interface OpenCMISS presents to users is also described, including specific examples exemplifying the extensibility and usability these tools provide the physiological modeling and simulation community. We conclude with some thoughts on future extension of OpenCMISS to make use of other community developed information standards, such as FieldML, SED-ML, and BioSignalML. Plans for the integration of accelerator code (graphical processing unit and field programmable gate array) generated from CellML models is also discussed. PMID:25601911
Gao, Yuan; Zhou, Weigui; Ao, Hong; Chu, Jian; Zhou, Quan; Zhou, Bo; Wang, Kang; Li, Yi; Xue, Peng
2016-01-01
With the increasing demands for better transmission speed and robust quality of service (QoS), the capacity constrained backhaul gradually becomes a bottleneck in cooperative wireless networks, e.g., in the Internet of Things (IoT) scenario in joint processing mode of LTE-Advanced Pro. This paper focuses on resource allocation within capacity constrained backhaul in uplink cooperative wireless networks, where two base stations (BSs) equipped with single antennae serve multiple single-antennae users via multi-carrier transmission mode. In this work, we propose a novel cooperative transmission scheme based on compress-and-forward with user pairing to solve the joint mixed integer programming problem. To maximize the system capacity under the limited backhaul, we formulate the joint optimization problem of user sorting, subcarrier mapping and backhaul resource sharing among different pairs (subcarriers for users). A novel robust and efficient centralized algorithm based on alternating optimization strategy and perfect mapping is proposed. Simulations show that our novel method can improve the system capacity significantly under the constraint of the backhaul resource compared with the blind alternatives. PMID:27077865
Multi-focused geospatial analysis using probes.
Butkiewicz, Thomas; Dou, Wenwen; Wartell, Zachary; Ribarsky, William; Chang, Remco
2008-01-01
Traditional geospatial information visualizations often present views that restrict the user to a single perspective. When zoomed out, local trends and anomalies become suppressed and lost; when zoomed in for local inspection, spatial awareness and comparison between regions become limited. In our model, coordinated visualizations are integrated within individual probe interfaces, which depict the local data in user-defined regions-of-interest. Our probe concept can be incorporated into a variety of geospatial visualizations to empower users with the ability to observe, coordinate, and compare data across multiple local regions. It is especially useful when dealing with complex simulations or analyses where behavior in various localities differs from other localities and from the system as a whole. We illustrate the effectiveness of our technique over traditional interfaces by incorporating it within three existing geospatial visualization systems: an agent-based social simulation, a census data exploration tool, and an 3D GIS environment for analyzing urban change over time. In each case, the probe-based interaction enhances spatial awareness, improves inspection and comparison capabilities, expands the range of scopes, and facilitates collaboration among multiple users.
Using a Java Web-based Graphical User Interface to access the SOHO Data Arch ive
NASA Astrophysics Data System (ADS)
Scholl, I.; Girard, Y.; Bykowski, A.
This paper presents the architecture of a Java web-based graphical interface dedicated to the access of the SOHO Data archive. This application allows local and remote users to search in the SOHO data catalog and retrieve the SOHO data files from the archive. It has been developed at MEDOC (Multi-Experiment Data and Operations Centre), located at the Institut d'Astrophysique Spatiale (Orsay, France), which is one of the European Archives for the SOHO data. This development is part of a joint effort between ESA, NASA and IAS in order to implement long term archive systems for the SOHO data. The software architecture is built as a client-server application using Java language and SQL above a set of components such as an HTTP server, a JDBC gateway, a RDBMS server, a data server and a Web browser. Since HTML pages and CGI scripts are not powerful enough to allow user interaction during a multi-instrument catalog search, this type of requirement enforces the choice of Java as the main language. We also discuss performance issues, security problems and portability on different Web browsers and operating syste ms.
User-assisted visual search and tracking across distributed multi-camera networks
NASA Astrophysics Data System (ADS)
Raja, Yogesh; Gong, Shaogang; Xiang, Tao
2011-11-01
Human CCTV operators face several challenges in their task which can lead to missed events, people or associations, including: (a) data overload in large distributed multi-camera environments; (b) short attention span; (c) limited knowledge of what to look for; and (d) lack of access to non-visual contextual intelligence to aid search. Developing a system to aid human operators and alleviate such burdens requires addressing the problem of automatic re-identification of people across disjoint camera views, a matching task made difficult by factors such as lighting, viewpoint and pose changes and for which absolute scoring approaches are not best suited. Accordingly, we describe a distributed multi-camera tracking (MCT) system to visually aid human operators in associating people and objects effectively over multiple disjoint camera views in a large public space. The system comprises three key novel components: (1) relative measures of ranking rather than absolute scoring to learn the best features for matching; (2) multi-camera behaviour profiling as higher-level knowledge to reduce the search space and increase the chance of finding correct matches; and (3) human-assisted data mining to interactively guide search and in the process recover missing detections and discover previously unknown associations. We provide an extensive evaluation of the greater effectiveness of the system as compared to existing approaches on industry-standard i-LIDS multi-camera data.
Koniotou, Marina; Evans, Bridie Angela; Chatters, Robin; Fothergill, Rachael; Garnsworthy, Christopher; Gaze, Sarah; Halter, Mary; Mason, Suzanne; Peconi, Julie; Porter, Alison; Siriwardena, A Niroshan; Toghill, Alun; Snooks, Helen
2015-07-10
Health services research is expected to involve service users as active partners in the research process, but few examples report how this has been achieved in practice in trials. We implemented a model to involve service users in a multi-centre randomised controlled trial in pre-hospital emergency care. We used the generic Standard Operating Procedure (SOP) from our Clinical Trials Unit (CTU) as the basis for creating a model to fit the context and population of the SAFER 2 trial. In our model, we planned to involve service users at all stages in the trial through decision-making forums at 3 levels: 1) strategic; 2) site (e.g. Wales; London; East Midlands); 3) local. We linked with charities and community groups to recruit people with experience of our study population. We collected notes of meetings alongside other documentary evidence such as attendance records and study documentation to track how we implemented our model. We involved service users at strategic, site and local level. We also added additional strategic level forums (Task and Finish Groups and Writing Days) where we included service users. Service user involvement varied in frequency and type across meetings, research stages and locations but stabilised and increased as the trial progressed. Involving service users in the SAFER 2 trial showed how it is feasible and achievable for patients, carers and potential patients sharing the demographic characteristics of our study population to collaborate in a multi-centre trial at the level which suited their health, location, skills and expertise. A standard model of involvement can be tailored by adopting a flexible approach to take account of the context and complexities of a multi-site trial. Current Controlled Trials ISRCTN60481756. Registered: 13 March 2009.
Pre-Service Teachers' Perspectives on Using Scenario-Based Virtual Worlds in Science Education
ERIC Educational Resources Information Center
Kennedy-Clark, Shannon
2011-01-01
This paper presents the findings of a study on the current knowledge and attitudes of pre-service teachers on the use of scenario-based multi-user virtual environments in science education. The 28 participants involved in the study were introduced to "Virtual Singapura," a multi-user virtual environment, and completed an open-ended questionnaire.…
A Low-Cost Wireless Multi-Presentation on Single Screen in Classroom Using Raspberry Pi
ERIC Educational Resources Information Center
Yulianto, Budi; Layona, Rita; Dewi, Lusiana Citra
2017-01-01
Smartphone has become a daily necessity in supporting the mobility of users, including teachers and students. The need of users to make multi-presentation via a smartphone wirelessly does not fit with the cost and multiplatform support. This study aims to produce a solution by using Raspberry Pi as a wireless digital media player that will be…
ERIC Educational Resources Information Center
Ketelhut, Diane Jass
2007-01-01
This exploratory study investigated data-gathering behaviors exhibited by 100 seventh-grade students as they participated in a scientific inquiry-based curriculum project delivered by a multi-user virtual environment (MUVE). This research examined the relationship between students' self-efficacy on entry into the authentic scientific activity and…
ERIC Educational Resources Information Center
Pellas, Nikolaos; Kazanidis, Ioannis; Konstantinou, Nikolaos; Georgiou, Georgia
2017-01-01
The present literature review builds on the results of 50 research articles published from 2000 until 2016. All these studies have successfully accomplished various learning tasks in the domain of Science, Technology, Engineering, and Mathematics (STEM) education using three-dimensional (3-D) multi-user virtual worlds for Primary, Secondary and…
Multi-User Domain Object Oriented (MOO) as a High School Procedure for Foreign Language Acquisition.
ERIC Educational Resources Information Center
Backer, James A.
Foreign language students experience added difficulty when they are isolated from native speakers and from the culture of the target language. It has been posited that MOO (Multi-User Domain Object Oriented) may help overcome the geographical isolation of these students. MOOs are Internet-based virtual worlds in which people from all over the real…
Computer systems and methods for the query and visualization of multidimensional databases
Stolte, Chris; Tang, Diane L; Hanrahan, Patrick
2015-03-03
A computer displays a graphical user interface on its display. The graphical user interface includes a schema information region and a data visualization region. The schema information region includes multiple operand names, each operand corresponding to one or more fields of a multi-dimensional database that includes at least one data hierarchy. The data visualization region includes a columns shelf and a rows shelf. The computer detects user actions to associate one or more first operands with the columns shelf and to associate one or more second operands with the rows shelf. The computer generates a visual table in the data visualization region in accordance with the user actions. The visual table includes one or more panes. Each pane has an x-axis defined based on data for the one or more first operands, and each pane has a y-axis defined based on data for the one or more second operands.
Computer systems and methods for the query and visualization of multidimensional databases
Stolte, Chris; Tang, Diane L.; Hanrahan, Patrick
2015-11-10
A computer displays a graphical user interface on its display. The graphical user interface includes a schema information region and a data visualization region. The schema information region includes a plurality of fields of a multi-dimensional database that includes at least one data hierarchy. The data visualization region includes a columns shelf and a rows shelf. The computer detects user actions to associate one or more first fields with the columns shelf and to associate one or more second fields with the rows shelf. The computer generates a visual table in the data visualization region in accordance with the user actions. The visual table includes one or more panes. Each pane has an x-axis defined based on data for the one or more first fields, and each pane has a y-axis defined based on data for the one or more second fields.
Understanding user needs for carbon monitoring information
NASA Astrophysics Data System (ADS)
Duren, R. M.; Macauley, M.; Gurney, K. R.; Saatchi, S. S.; Woodall, C. W.; Larsen, K.; Reidmiller, D.; Hockstad, L.; Weitz, M.; Croes, B.; Down, A.; West, T.; Mercury, M.
2015-12-01
The objectives of the Understanding User Needs project for NASA's Carbon Monitoring System (CMS) program are to: 1) engage the user community and identify needs for policy-relevant carbon monitoring information, 2) evaluate current and planned CMS data products with regard to their value for decision making, and 3) explore alternative methods for visualizing and communicating carbon monitoring information and associated uncertainties to decision makers and other stakeholders. To meet these objectives and help establish a sustained link between science and decision-making we have established a multi-disciplinary team that combines expertise in carbon-cycle science, engineering, economics, and carbon management and policy. We will present preliminary findings regarding emerging themes and needs for carbon information that may warrant increased attention by the science community. We will also demonstrate a new web-based tool that offers a common framework for facilitating user evaluation of carbon data products from multiple CMS projects.
NASA Technical Reports Server (NTRS)
1991-01-01
The technical effort and computer code enhancements performed during the sixth year of the Probabilistic Structural Analysis Methods program are summarized. Various capabilities are described to probabilistically combine structural response and structural resistance to compute component reliability. A library of structural resistance models is implemented in the Numerical Evaluations of Stochastic Structures Under Stress (NESSUS) code that included fatigue, fracture, creep, multi-factor interaction, and other important effects. In addition, a user interface was developed for user-defined resistance models. An accurate and efficient reliability method was developed and was successfully implemented in the NESSUS code to compute component reliability based on user-selected response and resistance models. A risk module was developed to compute component risk with respect to cost, performance, or user-defined criteria. The new component risk assessment capabilities were validated and demonstrated using several examples. Various supporting methodologies were also developed in support of component risk assessment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
2016-09-12
Mcqueuer is a simple tool that allows anyone from researchers to experienced developers to create multi-node/multi-core jobs by simply creating a file with a list of commands. Users simply combine tasks, which would otherwise each be their own job on the cluster, into a single file that is given to Mcqueuer. Mcqueuer then does the heavy lifting required to process the tasks in parallel in a single multi-node job. In addition, Mcqueuer provides load-balancing, which frees the user from having to worry about complex memory and CPU considerations, and instead focus on the processing itself.
NASA Technical Reports Server (NTRS)
Jacklin, S. A.; Leyland, J. A.; Warmbrodt, W.
1985-01-01
Modern control systems must typically perform real-time identification and control, as well as coordinate a host of other activities related to user interaction, online graphics, and file management. This paper discusses five global design considerations which are useful to integrate array processor, multimicroprocessor, and host computer system architectures into versatile, high-speed controllers. Such controllers are capable of very high control throughput, and can maintain constant interaction with the nonreal-time or user environment. As an application example, the architecture of a high-speed, closed-loop controller used to actively control helicopter vibration is briefly discussed. Although this system has been designed for use as the controller for real-time rotorcraft dynamics and control studies in a wind tunnel environment, the controller architecture can generally be applied to a wide range of automatic control applications.
Study of power management technology for orbital multi-100KWe applications. Volume 3: Requirements
NASA Technical Reports Server (NTRS)
Mildice, J. W.
1980-01-01
Mid to late 1980's power management technology needs to support development of a general purpose space platform, capable of suplying 100 to 250 KWe to a variety of users in low Earth orbit are examined. A typical, shuttle assembled and supplied space platform is illustred, along with a group of payloads which might reasonably be expected to use such a facility. Examination of platform and user power needs yields a set of power requirements used to evaluate power management options for life cycle cost effectivness. The most cost effective ac/dc and dc systems are evaluated, specifically to develop system details which lead to technology goals, including: array and transmission voltages, best frequency for ac power transmission, and advantages and disadvantages of ac and dc systems for this application. System and component requirements are compared with the state-of-the-art to identify areas where technological development is required.
A compact eyetracked optical see-through head-mounted display
NASA Astrophysics Data System (ADS)
Hua, Hong; Gao, Chunyu
2012-03-01
An eye-tracked head-mounted display (ET-HMD) system is able to display virtual images as a classical HMD does, while additionally tracking the gaze direction of the user. There is ample evidence that a fully-integrated ETHMD system offers multi-fold benefits, not only to fundamental scientific research but also to emerging applications of such technology. For instance eyetracking capability in HMDs adds a very valuable tool and objective metric for scientists to quantitatively assess user interaction with 3D environments and investigate the effectiveness of various 3D visualization technologies for various specific tasks including training, education, and augmented cognition tasks. In this paper, we present an innovative optical approach to the design of an optical see-through ET-HMD system based on freeform optical technology and an innovative optical scheme that uniquely combines the display optics with the eye imaging optics. A preliminary design of the described ET-HMD system will be presented.
NCAR's Research Data Archive: OPeNDAP Access for Complex Datasets
NASA Astrophysics Data System (ADS)
Dattore, R.; Worley, S. J.
2014-12-01
Many datasets have complex structures including hundreds of parameters and numerous vertical levels, grid resolutions, and temporal products. Making these data accessible is a challenge for a data provider. OPeNDAP is powerful protocol for delivering in real-time multi-file datasets that can be ingested by many analysis and visualization tools, but for these datasets there are too many choices about how to aggregate. Simple aggregation schemes can fail to support, or at least make it very challenging, for many potential studies based on complex datasets. We address this issue by using a rich file content metadata collection to create a real-time customized OPeNDAP service to match the full suite of access possibilities for complex datasets. The Climate Forecast System Reanalysis (CFSR) and it's extension, the Climate Forecast System Version 2 (CFSv2) datasets produced by the National Centers for Environmental Prediction (NCEP) and hosted by the Research Data Archive (RDA) at the Computational and Information Systems Laboratory (CISL) at NCAR are examples of complex datasets that are difficult to aggregate with existing data server software. CFSR and CFSv2 contain 141 distinct parameters on 152 vertical levels, six grid resolutions and 36 products (analyses, n-hour forecasts, multi-hour averages, etc.) where not all parameter/level combinations are available at all grid resolution/product combinations. These data are archived in the RDA with the data structure provided by the producer; no additional re-organization or aggregation have been applied. Since 2011, users have been able to request customized subsets (e.g. - temporal, parameter, spatial) from the CFSR/CFSv2, which are processed in delayed-mode and then downloaded to a user's system. Until now, the complexity has made it difficult to provide real-time OPeNDAP access to the data. We have developed a service that leverages the already-existing subsetting interface and allows users to create a virtual dataset with its own structure (das, dds). The user receives a URL to the customized dataset that can be used by existing tools to ingest, analyze, and visualize the data. This presentation will detail the metadata system and OPeNDAP server that enable user-customized real-time access and show an example of how a visualization tool can access the data.
Korczowski, L; Congedo, M; Jutten, C
2015-08-01
The classification of electroencephalographic (EEG) data recorded from multiple users simultaneously is an important challenge in the field of Brain-Computer Interface (BCI). In this paper we compare different approaches for classification of single-trials Event-Related Potential (ERP) on two subjects playing a collaborative BCI game. The minimum distance to mean (MDM) classifier in a Riemannian framework is extended to use the diversity of the inter-subjects spatio-temporal statistics (MDM-hyper) or to merge multiple classifiers (MDM-multi). We show that both these classifiers outperform significantly the mean performance of the two users and analogous classifiers based on the step-wise linear discriminant analysis. More importantly, the MDM-multi outperforms the performance of the best player within the pair.
Relating Narrative, Inquiry, and Inscriptions: Supporting Consequential Play
NASA Astrophysics Data System (ADS)
Barab, Sasha A.; Sadler, Troy D.; Heiselt, Conan; Hickey, Daniel; Zuiker, Steven
2007-02-01
In this paper we describe our research using a multi-user virtual environment, Quest Atlantis, to embed fourth grade students in an aquatic habitat simulation. Specifically targeted towards engaging students in a rich inquiry investigation, we layered a socio-scientific narrative and an interactive rule set into a multi-user virtual environment gaming engine to establish a virtual world through which students learned about science inquiry, water quality concepts, and the challenges in balancing scientific and socio-economic factors. Overall, students were clearly engaged, participated in rich scientific discourse, submitted quality work, and learned science content. Further, through participation in this narrative, students developed a rich perceptual, conceptual, and ethical understanding of science. This study suggests that multi-user virtual worlds can be effectively leveraged to support academic content learning.
Erratum to: Relating Narrative, Inquiry, and Inscriptions: Supporting Consequential Play
NASA Astrophysics Data System (ADS)
Barab, Sasha A.; Sadler, Troy D.; Heiselt, Conan; Hickey, Daniel; Zuiker, Steven
2010-08-01
In this paper we describe our research using a multi-user virtual environment, Quest Atlantis, to embed fourth grade students in an aquatic habitat simulation. Specifically targeted towards engaging students in a rich inquiry investigation, we layered a socio-scientific narrative and an interactive rule set into a multi-user virtual environment gaming engine to establish a virtual world through which students learned about science inquiry, water quality concepts, and the challenges in balancing scientific and socio-economic factors. Overall, students were clearly engaged, participated in rich scientific discourse, submitted quality work, and learned science content. Further, through participation in this narrative, students developed a rich perceptual, conceptual, and ethical understanding of science. This study suggests that multi-user virtual worlds can be effectively leveraged to support academic content learning.