Airport Surface Traffic Control Concept Formulation Study : Volume 3. Operations Analysis of O'Hare Airport - Part 2.

DOT National Transportation Integrated Search

1975-07-01

The volume presents the results of the quantitative analyses of the O'Hare ASTC System operations. The operations environments for the periods selected for detailed analysis of the ASDE films and controller communications recording are described. Fol...

Space station operating system study

NASA Technical Reports Server (NTRS)

Horn, Albert E.; Harwell, Morris C.

1988-01-01

The current phase of the Space Station Operating System study is based on the analysis, evaluation, and comparison of the operating systems implemented on the computer systems and workstations in the software development laboratory. Primary emphasis has been placed on the DEC MicroVMS operating system as implemented on the MicroVax II computer, with comparative analysis of the SUN UNIX system on the SUN 3/260 workstation computer, and to a limited extent, the IBM PC/AT microcomputer running PC-DOS. Some benchmark development and testing was also done for the Motorola MC68010 (VM03 system) before the system was taken from the laboratory. These systems were studied with the objective of determining their capability to support Space Station software development requirements, specifically for multi-tasking and real-time applications. The methodology utilized consisted of development, execution, and analysis of benchmark programs and test software, and the experimentation and analysis of specific features of the system or compilers in the study.

Meta-analysis: pre-operative infliximab treatment and short-term post-operative complications in patients with ulcerative colitis.

PubMed

Yang, Z; Wu, Q; Wu, K; Fan, D

2010-02-15

Infliximab was approved for use in ulcerative colitis in recent years. It has been debated if infliximab increases the risk of post-operative complications in patients with ulcerative colitis. To perform a meta-analysis that examines the relationship between preoperative infliximab treatment and short-term post-operative complications in patients with ulcerative colitis. We searched the PubMed and MEDLINE databases to identify observational studies on the impact of pre-operative infliximab use on short-term post-operative complications in ulcerative colitis. Infectious complications mainly included wound infection, sepsis and abscess, whereas non-infectious complications included intestinal obstruction, thromboembolism and gastrointestinal haemorrhage. Pooled odds ratios (ORs) were calculated for each relationship. A total of 5 studies and 706 patients were included in our meta-analysis. Overall, we did not find a strong association between pre-operative treatment of infliximab and short-term infectious [OR 2.24, 95% confidence interval (CI) 0.63-7.95] or non-infectious (OR 0.85, 95% CI 0.50-1.45) post-operative complications in ulcerative colitis patients. On the contrary, we discovered that pre-operative infliximab use increased short-term total post-operative complications (OR 1.80, 95% CI 1.12-2.87). Pre-operative infliximab use increased the risk of short-term post-operative complications. Subgroup analysis is underpowered to assess the nature of these complications but shows a trend towards increased post-operative infection.

Study on the Preliminary Design of ARGO-M Operation System

NASA Astrophysics Data System (ADS)

Seo, Yoon-Kyung; Lim, Hyung-Chul; Rew, Dong-Young; Jo, Jung Hyun; Park, Jong-Uk; Park, Eun-Seo; Park, Jang-Hyun

2010-12-01

Korea Astronomy and Space Science Institute has been developing one mobile satellite laser ranging system named as accurate ranging system for geodetic observation-mobile (ARGO-M). Preliminary design of ARGO-M operation system (AOS) which is one of the ARGO-M subsystems was completed in 2009. Preliminary design results are applied to the following development phase by performing detailed design with analysis of pre-defined requirements and analysis of the derived specifications. This paper addresses the preliminary design of the whole AOS. The design results in operation and control part which is a key part in the operation system are described in detail. Analysis results of the interface between operation-supporting hardware and the control computer are summarized, which is necessary in defining the requirements for the operation-supporting hardware. Results of this study are expected to be used in the critical design phase to finalize the design process.

Investigation on sense of control parameters for joystick interface in remote operated container crane application

NASA Astrophysics Data System (ADS)

Abdullah, U. N. N.; Handroos, H.

2017-09-01

Introduction: This paper presents the study of sense of control parameters to improve the lack of direct motion feeling through remote operated container crane station (ROCCS) joystick interface. The investigations of the parameters in this study are important to develop the engineering parameters related to the sense of control goal in the next design process. Methodology: Structured interviews and observations were conducted to obtain the user experience data from thirteen remote container crane operators from two international terminals. Then, interview analysis, task analysis, activity analysis and time line analysis were conducted to compare and contrast the results from interviews and observations. Results: Four experience parameters were identified to support the sense of control goal in the later design improvement of the ROCC joystick interface. The significance of difficulties to control, unsynchronized movements, facilitate in control and decision making in unexpected situation as parameters to the sense of control goal were validated by' feedbacks from operators as well as analysis. Contribution: This study provides feedback directly from end users towards developing a sustainable control interface for ROCCS in specific and remote operated off-road vehicles in general.

Orbital operations study. Volume 2: Interfacing activities analysis. Part 4: Support operations activity group

NASA Technical Reports Server (NTRS)

Steinwachs, W. L.; Patrick, J. W.; Galvin, D. M.; Turkel, S. H.

1972-01-01

The findings of the support operations activity group of the orbital operations study are presented. Element interfaces, alternate approaches, design concepts, operational procedures, functional requirements, design influences, and approach selection are presented. The following areas are considered: (1) crew transfer, (2) cargo transfer, (3) propellant transfer, (4) attached element operations, and (5) attached element transport.

Meta-analysis of pre-operative magnetic resonance imaging (MRI) and surgical treatment for breast cancer.

PubMed

Houssami, Nehmat; Turner, Robin M; Morrow, Monica

2017-09-01

Although there is no consensus on whether pre-operative MRI in women with breast cancer (BC) benefits surgical treatment, MRI continues to be used pre-operatively in practice. This meta-analysis examines the association between pre-operative MRI and surgical outcomes in BC. A systematic review was performed to identify studies reporting quantitative data on pre-operative MRI and surgical outcomes (without restriction by type of surgery received or type of BC) and using a controlled design. Random-effects logistic regression calculated the pooled odds ratio (OR) for each surgical outcome (MRI vs. no-MRI groups), and estimated ORs stratified by study-level age. Subgroup analysis was performed for invasive lobular cancer (ILC). Nineteen studies met eligibility criteria: 3 RCTs and 16 comparative studies that included newly diagnosed BC of any type except for three studies restricted to ILC. Primary analysis (85,975 subjects) showed that pre-operative MRI was associated with increased odds of receiving mastectomy [OR 1.39 (1.23, 1.57); p < 0.001]; similar findings were shown in analyses stratified by study-level median age. Secondary analyses did not find statistical evidence of an effect of MRI on the rates of re-excision, re-operation, or positive margins; however, MRI was significantly associated with increased odds of receiving contralateral prophylactic mastectomy [OR 1.91 (1.25, 2.91); p = 0.003]. Subgroup analysis for ILC did not find any association between MRI and the odds of receiving mastectomy [OR 1.00 (0.75, 1.33); p = 0.988] or the odds of re-excision [OR 0.65 (0.35, 1.24); p = 0.192]. Pre-operative MRI is associated with increased odds of receiving ipsilateral mastectomy and contralateral prophylactic mastectomy as surgical treatment in newly diagnosed BC patients.

TDRSS operations control analysis study

NASA Technical Reports Server (NTRS)

1976-01-01

The use of an operational Tracking and Data Relay Satellite System (TDRSS) and the remaining ground stations for the STDN (GSTDN) was investigated. The operational aspects of TDRSS concepts, GSTDN as a 14-site network, and GSTDN as a 7 site-network were compared and operations control concepts for the configurations developed. Man/machine interface, scheduling system, and hardware/software tradeoff analyses were among the factors considered in the analysis.

Radar-based alert system to operate a sewerage network: relevance and operational effectiveness after several years of use.

PubMed

Faure, D; Payrastre, O; Auchet, P

2005-01-01

Since January 2000, the sewerage network of a very urbanised catchment area in the Greater Nancy Urban Community has been operated according to the alarms generated in real time by a storm alert system using weather radar data. This alert system is based on an automatic identification of intense rain cells in the radar images. This paper presents the characteristics of this alert system and synthesises the main results of two complementary studies realised in 2002 in order to estimate the relevance and the operational effectiveness of the alert system. The first study consisted in an off-line analysis of almost 50,000 intense rain cells detected in four years of historical radar data. The second study was an analysis of the experience feedback after two years of operational use of this alert system. The results of these studies are discussed in function of the initial operational objectives.

Applying Bayesian Modeling and Receiver Operating Characteristic Methodologies for Test Utility Analysis

ERIC Educational Resources Information Center

Wang, Qiu; Diemer, Matthew A.; Maier, Kimberly S.

2013-01-01

This study integrated Bayesian hierarchical modeling and receiver operating characteristic analysis (BROCA) to evaluate how interest strength (IS) and interest differentiation (ID) predicted low–socioeconomic status (SES) youth's interest-major congruence (IMC). Using large-scale Kuder Career Search online-assessment data, this study fit three…

Airport Surface Traffic Control Concept Formulation Study : Volume II. Operations Analysis of O'Hare Airport - Part 1

DOT National Transportation Integrated Search

1975-07-01

The report describes the approach followed and the analysis techniques employed in the performance of the operations analysis of the current ASTC system for the baseline airport, O'Hare International Airport, Chicago, Illinois. It also describes the ...

Fixed Route Comprehensive Operational Analysis, 1994 Operating Year. Fourth Installment, Route 2: Berkshire Shopping Center Analysis

DOT National Transportation Integrated Search

1995-03-01

The study evaluated the performance of the service, analyzed possible alternatives, and recommended several service changes, which took effect in August of 1993. By use of ongoing data collection, HART intends to provide continual analysis of the ser...

Time and frequency domain characteristics of detrending-operation-based scaling analysis: Exact DFA and DMA frequency responses

NASA Astrophysics Data System (ADS)

Kiyono, Ken; Tsujimoto, Yutaka

2016-07-01

We develop a general framework to study the time and frequency domain characteristics of detrending-operation-based scaling analysis methods, such as detrended fluctuation analysis (DFA) and detrending moving average (DMA) analysis. In this framework, using either the time or frequency domain approach, the frequency responses of detrending operations are calculated analytically. Although the frequency domain approach based on conventional linear analysis techniques is only applicable to linear detrending operations, the time domain approach presented here is applicable to both linear and nonlinear detrending operations. Furthermore, using the relationship between the time and frequency domain representations of the frequency responses, the frequency domain characteristics of nonlinear detrending operations can be obtained. Based on the calculated frequency responses, it is possible to establish a direct connection between the root-mean-square deviation of the detrending-operation-based scaling analysis and the power spectrum for linear stochastic processes. Here, by applying our methods to DFA and DMA, including higher-order cases, exact frequency responses are calculated. In addition, we analytically investigate the cutoff frequencies of DFA and DMA detrending operations and show that these frequencies are not optimally adjusted to coincide with the corresponding time scale.

Time and frequency domain characteristics of detrending-operation-based scaling analysis: Exact DFA and DMA frequency responses.

PubMed

Kiyono, Ken; Tsujimoto, Yutaka

2016-07-01

We develop a general framework to study the time and frequency domain characteristics of detrending-operation-based scaling analysis methods, such as detrended fluctuation analysis (DFA) and detrending moving average (DMA) analysis. In this framework, using either the time or frequency domain approach, the frequency responses of detrending operations are calculated analytically. Although the frequency domain approach based on conventional linear analysis techniques is only applicable to linear detrending operations, the time domain approach presented here is applicable to both linear and nonlinear detrending operations. Furthermore, using the relationship between the time and frequency domain representations of the frequency responses, the frequency domain characteristics of nonlinear detrending operations can be obtained. Based on the calculated frequency responses, it is possible to establish a direct connection between the root-mean-square deviation of the detrending-operation-based scaling analysis and the power spectrum for linear stochastic processes. Here, by applying our methods to DFA and DMA, including higher-order cases, exact frequency responses are calculated. In addition, we analytically investigate the cutoff frequencies of DFA and DMA detrending operations and show that these frequencies are not optimally adjusted to coincide with the corresponding time scale.

Extended System Operations Studies for Automated Guideway Transit Systems

DOT National Transportation Integrated Search

1982-02-01

The objectives of the System Operations Studies (SOS) of the Automated Guideway Transit Technology (AGTT) program was to develop models for the analysis of system operations, to evaluate AGT system performance and cost, and to establish guidelines fo...

A Satellite Mortality Study to Support Space Systems Lifetime Prediction

NASA Technical Reports Server (NTRS)

Fox, George; Salazar, Ronald; Habib-Agahi, Hamid; Dubos, Gregory

2013-01-01

Estimating the operational lifetime of satellites and spacecraft is a complex process. Operational lifetime can differ from mission design lifetime for a variety of reasons. Unexpected mortality can occur due to human errors in design and fabrication, to human errors in launch and operations, to random anomalies of hardware and software or even satellite function degradation or technology change, leading to unrealized economic or mission return. This study focuses on data collection of public information using, for the first time, a large, publically available dataset, and preliminary analysis of satellite lifetimes, both operational lifetime and design lifetime. The objective of this study is the illustration of the relationship of design life to actual lifetime for some representative classes of satellites and spacecraft. First, a Weibull and Exponential lifetime analysis comparison is performed on the ratio of mission operating lifetime to design life, accounting for terminated and ongoing missions. Next a Kaplan-Meier survivor function, standard practice for clinical trials analysis, is estimated from operating lifetime. Bootstrap resampling is used to provide uncertainty estimates of selected survival probabilities. This study highlights the need for more detailed databases and engineering reliability models of satellite lifetime that include satellite systems and subsystems, operations procedures and environmental characteristics to support the design of complex, multi-generation, long-lived space systems in Earth orbit.

Space Operations Center system analysis study extension. Volume 4, book 2: SOC system analysis report

NASA Technical Reports Server (NTRS)

1982-01-01

The Space Operations Center (SOC) orbital space station research missions integration, crew requirements, SOC operations, and configurations are analyzed. Potential research and applications missions and their requirements are described. The capabilities of SOC are compared with user requirements. The SOC/space shuttle and shuttle-derived vehicle flight support operations and SOC orbital operations are described. Module configurations and systems options, SOC/external tank configurations, and configurations for geostationary orbits are described. Crew and systems safety configurations are summarized.

Renewable Electricity Futures. Operational Analysis of the Western Interconnection at Very High Renewable Penetrations

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

Brinkman, Gregory

2015-09-01

The Renewable Electricity Futures Study (RE Futures)--an analysis of the costs and grid impacts of integrating large amounts of renewable electricity generation into the U.S. power system--examined renewable energy resources, technical issues regarding the integration of these resources into the grid, and the costs associated with high renewable penetration scenarios. These scenarios included up to 90% of annual generation from renewable sources, although most of the analysis was focused on 80% penetration scenarios. Hourly production cost modeling was performed to understand the operational impacts of high penetrations. One of the conclusions of RE Futures was that further work was necessarymore » to understand whether the operation of the system was possible at sub-hourly time scales and during transient events. This study aimed to address part of this by modeling the operation of the power system at sub-hourly time scales using newer methodologies and updated data sets for transmission and generation infrastructure. The goal of this work was to perform a detailed, sub-hourly analysis of very high penetration scenarios for a single interconnection (the Western Interconnection). It focused on operational impacts, and it helps verify that the operational results from the capacity expansion models are useful. The primary conclusion of this study is that sub-hourly operation of the grid is possible with renewable generation levels between 80% and 90%.« less

Analysis of Cycling Costs in Western Wind and Solar Integration Study

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

Jordan, G.; Venkataraman, S.

The Western Wind and Solar Integration Study (WWSIS) examined the impact of up to 30% penetration of variable renewable generation on the Western Electricity Coordinating Council system. Although start-up costs and higher operating costs because of part-load operation of thermal generators were included in the analysis, further investigation of additional costs associated with thermal unit cycling was deemed worthwhile. These additional cycling costs can be attributed to increases in capital as well as operations and maintenance costs because of wear and tear associated with increased unit cycling. This analysis examines the additional cycling costs of the thermal fleet by leveragingmore » the results of WWSIS Phase 1 study.« less

The application of DEA (Data Envelopment Analysis) window analysis in the assessment of influence on operational efficiencies after the establishment of branched hospitals.

PubMed

Jia, Tongying; Yuan, Huiyun

2017-04-12

Many large-scaled public hospitals have established branched hospitals in China. This study is to provide evidence for strategy making on the management and development of multi-branched hospitals by evaluating and comparing the operational efficiencies of different hospitals before and after their establishment of branched hospitals. DEA (Data Envelopment Analysis) window analysis was performed on a 7-year data pool from five public hospitals provided by health authorities and institutional surveys. The operational efficiencies of sample hospitals measured in this study (including technical efficiency, pure technical efficiency and scale efficiency) had overall trends towards increase during this 7-year period of time, however, a temporary downturn occurred shortly after the establishment of branched hospitals; pure technical efficiency contributed more to the improvement of technical efficiency compared to scale efficiency. The establishment of branched-hospitals did not lead to a long-term negative effect on hospital operational efficiencies. Our data indicated the importance of improving scale efficiency via the optimization of organizational management, as well as the advantage of a different form of branch-establishment, merging and reorganization. This study brought an insight into the practical application of DEA window analysis on the assessment of hospital operational efficiencies.

Music and communication in the operating theatre.

PubMed

Weldon, Sharon-Marie; Korkiakangas, Terhi; Bezemer, Jeff; Kneebone, Roger

2015-12-01

To observe the extent and the detail with which playing music can impact on communication in the operating theatre. According to the cited sources, music is played in 53-72% of surgical operations performed. Noise levels in the operating theatre already exceed World Health Organisation recommendations. There is currently a divide in opinions on the playing of music in operating theatres, with few studies conducted and no policies or guidance provided. An ethnographic observational study of teamwork in operating theatres through video recordings. Quantitative and qualitative data analysis approaches were used. This study was conducted between 2012-2013 in the UK. Video recordings of 20 operations over six months in two operating theatres were captured. The recordings were divided into music and non-music playing cases. Each case was logged using a request/response sequence identified through interactional analysis. Statistical analysis, using a χ(2) , explored the difference between the proportion of request repetitions and whether music was playing or not. Further interactional analysis was conducted for each request repetition. Request/response observations (N = 5203) were documented. A chi-square test revealed that repeated requests were five times more likely to occur in cases that played music than those that did not. A repeated request can add 4-68 seconds each to operation time and increased tensions due to frustration at ineffective communication. Music played in the operating theatre can interfere with team communication, yet is seldom recognized as a potential safety hazard. Decisions around whether music is played and around the choice of music and its volume, are determined largely by surgeons. Frank discussions between clinicians, managers, patients and governing bodies should be encouraged for recommendations and guidance to be developed. © 2015 John Wiley & Sons Ltd.

Application Performance Analysis and Efficient Execution on Systems with multi-core CPUs, GPUs and MICs: A Case Study with Microscopy Image Analysis

PubMed Central

Teodoro, George; Kurc, Tahsin; Andrade, Guilherme; Kong, Jun; Ferreira, Renato; Saltz, Joel

2015-01-01

We carry out a comparative performance study of multi-core CPUs, GPUs and Intel Xeon Phi (Many Integrated Core-MIC) with a microscopy image analysis application. We experimentally evaluate the performance of computing devices on core operations of the application. We correlate the observed performance with the characteristics of computing devices and data access patterns, computation complexities, and parallelization forms of the operations. The results show a significant variability in the performance of operations with respect to the device used. The performances of operations with regular data access are comparable or sometimes better on a MIC than that on a GPU. GPUs are more efficient than MICs for operations that access data irregularly, because of the lower bandwidth of the MIC for random data accesses. We propose new performance-aware scheduling strategies that consider variabilities in operation speedups. Our scheduling strategies significantly improve application performance compared to classic strategies in hybrid configurations. PMID:28239253

Analysis of the Apollo spacecraft operational data management system. Executive summary

NASA Technical Reports Server (NTRS)

1971-01-01

A study was made of Apollo, Skylab, and several other data management systems to determine those techniques which could be applied to the management of operational data for future manned spacecraft programs. The results of the study are presented and include: (1) an analysis of present data management systems, (2) a list of requirements for future operational data management systems, (3) an evaluation of automated data management techniques, and (4) a plan for data management applicable to future space programs.

Traffic operational evaluation of traffic impact analysis (TIA) case sites.

DOT National Transportation Integrated Search

2010-09-22

This report summarizes traffic operational evaluation of six select traffic impact analysis (TIA) case sites and the effectiveness of forecasting methods used in TIA studies. Six TIA case sites comprising 15 signalized intersections and 2 unsignalize...

Intelligent Operation and Maintenance of Micro-grid Technology and System Development

NASA Astrophysics Data System (ADS)

Fu, Ming; Song, Jinyan; Zhao, Jingtao; Du, Jian

2018-01-01

In order to achieve the micro-grid operation and management, Studying the micro-grid operation and maintenance knowledge base. Based on the advanced Petri net theory, the fault diagnosis model of micro-grid is established, and the intelligent diagnosis and analysis method of micro-grid fault is put forward. Based on the technology, the functional system and architecture of the intelligent operation and maintenance system of micro-grid are studied, and the microcomputer fault diagnosis function is introduced in detail. Finally, the system is deployed based on the micro-grid of a park, and the micro-grid fault diagnosis and analysis is carried out based on the micro-grid operation. The system operation and maintenance function interface is displayed, which verifies the correctness and reliability of the system.

Space station needs, attributes and architectural options study. Volume 2: Mission analysis

NASA Technical Reports Server (NTRS)

1983-01-01

Space environment studies, astrophysics, Earth environment, life sciences, and material sciences are discussed. Commercial communication, materials processing, and Earth observation missions are addressed. Technology development, space operations, scenarios of operational capability, mission requirements, and benefits analysis results for space-produced gallium arsenide crystals, direct broadcasting satellite systems, and a high inclination space station are covered.

Preventive Effect on Post-Operative Pneumonia of Oral Health Care among Patients Who Undergo Esophageal Resection: A Multi-Center Retrospective Study.

PubMed

Soutome, Sakiko; Yanamoto, Souichi; Funahara, Madoka; Hasegawa, Takumi; Komori, Takahide; Oho, Takahiko; Umeda, Masahiro

2016-08-01

Post-operative pneumonia is a frequent and possibly fatal complication of esophagectomy and is likely caused by aspiration of oropharyngeal fluid that contains pathogenic micro-organisms. We conducted a multi-center retrospective study to investigate the preventive effect of oral health care on post-operative pneumonia among patients with esophageal cancer who underwent esophagectomy. A total of 280 patients underwent esophagectomy at three university hospitals. These patients were divided retrospectively into those who received pre-operative oral care from dentists and dental hygienists (oral care group; n = 173) and those who did not receive such care (control group; n = 107). We evaluated the correlations between the occurrence of post-operative pneumonia and 18 predictive variables (patient factors, tumor factors, treatment factors, and pre-operative oral care) using the χ(2) test and logistic regression analysis. The differences of mean hospital days and mortality rate in both groups were analyzed by the Student t-test. Age, post-operative dysphagia, and absence of pre-operative oral care were correlated significantly with post-operative pneumonia in the univariable analysis. Multivariable analysis revealed that diabetes mellitus, post-operative dysphagia, and the absence of pre-operative oral care were independent risk factors for post-operative pneumonia. The mean hospital stay and mortality rate did not differ between the oral care and control groups. Pre-operative oral care may be an effective and easy method to prevent post-operative pneumonia in patients who are undergoing esophagectomy.

Space-based solar power conversion and delivery systems (study), engineering analysis

NASA Technical Reports Server (NTRS)

Nathan, C. A.

1975-01-01

A systems analysis of synchronous, orbit-based power generation and relay systems that could be operational in the 1990's is described along with a comparison with earth-based systems to be operational in the same time frame. Operational and economic requirements for the orbiting systems and near term research activities which will be required to assure feasibility, development, launch and operational capabilities of such systems in the post- 1990 time frame are examined.

Track train dynamics analysis and test program: Methodology development for the derailment safety analysis of six-axle locomotives

NASA Technical Reports Server (NTRS)

Marcotte, P. P.; Mathewson, K. J. R.

1982-01-01

The operational safety of six axle locomotives is analyzed. A locomotive model with corresponding data on suspension characteristics, a method of track defect characterization, and a method of characterizing operational safety are used. A user oriented software package was developed as part of the methodology and was used to study the effect (on operational safety) of various locomotive parameters and operational conditions such as speed, tractive effort, and track curvature. The operational safety of three different locomotive designs was investigated.

Marginal analysis in assessing factors contributing time to physician in the Emergency Department using operations data.

PubMed

Pathan, Sameer A; Bhutta, Zain A; Moinudheen, Jibin; Jenkins, Dominic; Silva, Ashwin D; Sharma, Yogdutt; Saleh, Warda A; Khudabakhsh, Zeenat; Irfan, Furqan B; Thomas, Stephen H

2016-01-01

Background: Standard Emergency Department (ED) operations goals include minimization of the time interval (tMD) between patients' initial ED presentation and initial physician evaluation. This study assessed factors known (or suspected) to influence tMD with a two-step goal. The first step was generation of a multivariate model identifying parameters associated with prolongation of tMD at a single study center. The second step was the use of a study center-specific multivariate tMD model as a basis for predictive marginal probability analysis; the marginal model allowed for prediction of the degree of ED operations benefit that would be affected with specific ED operations improvements. Methods: The study was conducted using one month (May 2015) of data obtained from an ED administrative database (EDAD) in an urban academic tertiary ED with an annual census of approximately 500,000; during the study month, the ED saw 39,593 cases. The EDAD data were used to generate a multivariate linear regression model assessing the various demographic and operational covariates' effects on the dependent variable tMD. Predictive marginal probability analysis was used to calculate the relative contributions of key covariates as well as demonstrate the likely tMD impact on modifying those covariates with operational improvements. Analyses were conducted with Stata 14MP, with significance defined at p  < 0.05 and confidence intervals (CIs) reported at the 95% level. Results: In an acceptable linear regression model that accounted for just over half of the overall variance in tMD (adjusted r 2 0.51), important contributors to tMD included shift census ( p  = 0.008), shift time of day ( p  = 0.002), and physician coverage n ( p  = 0.004). These strong associations remained even after adjusting for each other and other covariates. Marginal predictive probability analysis was used to predict the overall tMD impact (improvement from 50 to 43 minutes, p  < 0.001) of consistent staffing with 22 physicians. Conclusions: The analysis identified expected variables contributing to tMD with regression demonstrating significance and effect magnitude of alterations in covariates including patient census, shift time of day, and number of physicians. Marginal analysis provided operationally useful demonstration of the need to adjust physician coverage numbers, prompting changes at the study ED. The methods used in this analysis may prove useful in other EDs wishing to analyze operations information with the goal of predicting which interventions may have the most benefit.

Applying analysis tools in planning for operations : case study #1 -- operations strategy impact reference and deployment guidance

DOT National Transportation Integrated Search

2009-09-01

More and more, transportation system operators are seeing the benefits of strengthening links between planning and operations. A critical element in improving transportation decision-making and the effectiveness of transportation systems related to o...

Earth Observatory Satellite system definition study. Report no. 3: Design/cost tradeoff studies. Appendix A: EOS program WBS dictionary. Appendix B: EOS mission functional analysis

NASA Technical Reports Server (NTRS)

1974-01-01

The work breakdown structure (WBS) dictionary for the Earth Observatory Satellite (EOS) is defined. The various elements of the EOS program are examined to include the aggregate of hardware, computer software, services, and data required to develop, produce, test, support, and operate the space vehicle and the companion ground data management system. A functional analysis of the EOS mission is developed. The operations for three typical EOS missions, Delta, Titan, and Shuttle launched are considered. The functions were determined for the top program elements, and the mission operations, function 2.0, was expanded to level one functions. Selection of ten level one functions for further analysis to level two and three functions were based on concern for the EOS operations and associated interfaces.

Lunar base surface mission operations. Lunar Base Systems Study (LBSS) task 4.1

NASA Technical Reports Server (NTRS)

1987-01-01

The purpose was to perform an analysis of the surface operations associated with a human-tended lunar base. Specifically, the study defined surface elements and developed mission manifests for a selected base scenario, determined the nature of surface operations associated with this scenario, generated a preliminary crew extravehicular and intravehicular activity (EVA/IVA) time resource schedule for conducting the missions, and proposed concepts for utilizing remotely operated equipment to perform repetitious or hazardous surface tasks. The operations analysis was performed on a 6 year period of human-tended lunar base operation prior to permanent occupancy. The baseline scenario was derived from a modified version of the civil needs database (CNDB) scenario. This scenario emphasizes achievement of a limited set of science and exploration objectives while emplacing the minimum habitability elements required for a permanent base.

Orbital operation study. Volume 2: Interfacing activities analysis. Part 1: Introduction and summary

NASA Technical Reports Server (NTRS)

Anderson, N. R.

1972-01-01

The summary of the interfacing activity analyses for the orbital operations study is presented. The significant analyses are grouped into categories as follows: (1) structural and mechanical activity, (2) data management, and (3) support operations. Specific subjects concerning payload deployment, communications, rendezvous, and stationkeeping are discussed.

Does the pre-operative serum phosphate level predict early hypocalcaemia following parathyroidectomy for primary hyperparathyroidism?

PubMed

Ellul, David; Townsley, Richard Brendan; Clark, Louise Jane

2013-06-01

Hypocalcaemia is a significant post-operative complication following parathyroidectomy. Early identification of risk factors can help pre-empt hypocalcaemia and avoid serious sequelae. It can also help identify those patients that are not suitable for day-case surgery. The aim of this study was to analyse the predictive value of the pre-operative serum phosphate level as an indicator for developing hypocalcaemia post-operatively in patients undergoing parathyroidectomy for primary hyperparathyroidism. We performed a retrospective review of all patients who underwent parathyroidectomy between 2008 and 2010 at the Southern General Hospital in Glasgow. Data collected included the number of parathyroid glands excised and their histology, pre-operative adjusted calcium (aCa) and phosphate levels, post-operative aCa at 6 and 24 h following surgery, and the fall in aCa levels in the first 6 h and 24 h following surgery. Minitab Statistical Analysis (Version 15) was used for data analysis. Fifty-six patients underwent parathyroidectomy in the study period. Twelve patients were excluded for various reasons including incomplete records and secondary hyperparathyroidism. Patients given calcium or Vitamin D supplements immediately post-operatively were also excluded. Statistical analysis showed no significant correlation between the pre-operative phosphate level and the post-operative decline in aCa level 6 h or 24 h following surgery. Patients with a lower phosphate level pre-operatively were not at risk of a more drastic fall in calcium levels following parathyroidectomy. The pre-operative phosphate level was not found to be predictive of post-operative hypocalcaemia in our study. Copyright © 2012 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

Emission rate modeling and risk assessment at an automobile plant from painting operations

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

Kumar, A.; Shrivastava, A.; Kulkarni, A.

Pollution from automobile plants from painting operations has been addressed in the Clean Act Amendments (1990). The estimation of pollutant emissions from automobile painting operation were done mostly by approximate procedures than by actual calculations. The purpose of this study was to develop a methodology for calculating the emissions of the pollutants from painting operation in an automobile plant. Five scenarios involving an automobile painting operation, located in Columbus (Ohio), were studied for pollutant emission and concomitant risk associated with that. In the study of risk, a sensitivity analysis was done using Crystal Ball{reg{underscore}sign} on the parameters involved in risk.more » This software uses the Monte Carlo principle. The most sensitive factor in the risk analysis was the ground level concentration of the pollutants. All scenarios studied met the safety goal (a risk value of 1 x 10{sup {minus}6}) with different confidence levels. The highest level of confidence in meeting the safety goal was displayed by Scenario 1 (Alpha Industries). The results from the scenarios suggest that risk is associated with the quantity of released toxic pollutants. The sensitivity analysis of the various parameter shows that average spray rate of paint is the most important parameter in the estimation of pollutants from the painting operations. The entire study is a complete module that can be used by the environmental pollution control agencies for estimation of pollution levels and estimation of associated risk. The study can be further extended to other operations in an automobile industry or to different industries.« less

Applying analysis tools in planning for operations : case study #3 -- using archived data as a tool for operations planning

DOT National Transportation Integrated Search

2009-09-01

More and more, transportation system operators are seeing the benefits of strengthening links between planning and operations. A critical element in improving transportation decision-making and the effectiveness of transportation systems related to o...

Astronaut activity in weightlessness and unsupported space

NASA Technical Reports Server (NTRS)

Ivanov, Y. A.; Popov, V. A.; Kachaturyants, L. S.

1975-01-01

For the purpose of study of the performance ability of a human operator in prolonged weightless conditions was studied by the following methods: (1) psychophysiological analysis of certain operations; (2) the dynamic characteristics of a man, included in a model control system, with direct and delayed feedback; (3) evaluation of the singularities of analysis and quality of the working memory, in working with outlines of patterned and random lines; and (4) biomechanical analysis of spatial orientation and motor activity in unsupported space.

Satellite Power Systems (SPS) concept definition study. Volume 5: Transportation and operations analysis. [heavy lift launch and orbit transfer vehicles for orbital assembly

NASA Technical Reports Server (NTRS)

Hanley, G.

1978-01-01

The development of transportation systems to support the operations required for the orbital assembly of a 5-gigawatt satellite is discussed as well as the construction of a ground receiving antenna (rectenna). Topics covered include heavy lift launch vehicle configurations for Earth-to LEO transport; the use of chemical, nuclear, and electric orbit transfer vehicles for LEO to GEO operations; personnel transport systems; ground operations; end-to-end analysis of the construction, operation, and maintenance of the satellite and rectenna; propellant production and storage; and payload packaging.

Orbital operations study. Volume 1: Mission analysis

NASA Technical Reports Server (NTRS)

Steinwachs, W. L.

1972-01-01

The final report of the orbital operations study and a summary of the 25 elements in the study inventory are presented. Fourteen interfacing activities are defined. Eleven mission models encompassing all potential interfacing element pairs and interfacing activities are included.

Space tug economic analysis study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1972-01-01

An economic analysis of space tug operations is presented. The space tug is defined as any liquid propulsion stage under 100,000 pounds propellant loading that is flown from the space shuttle cargo bay. Two classes of vehicles are the orbit injection stages and reusable space tugs. The vehicle configurations, propellant combinations, and operating modes used for the study are reported. The summary contains data on the study approach, results, conclusions, and recommendations.

Critical analysis of submerged membrane sequencing batch reactor operating conditions.

PubMed

McAdam, Ewan; Judd, Simon J; Gildemeister, René; Drews, Anja; Kraume, Matthias

2005-10-01

To evaluate the Submerged Membrane Sequencing Batch Reactor process, several short-term studies were conducted to define critical flux, membrane aeration and intermittent filtration operation. Critical flux trials indicated that as mixed liquor suspended solids increased in concentration so would the propensity for membrane fouling. Consequently in order to characterise the impact of biomass concentration increase (that develops during permeate withdrawal) upon submerged microfiltration operation, two longer term studies were conducted, one with a falling hydraulic head and another with a continuous hydraulic head (as in membrane bio-reactors). Trans membrane pressure data was used to predict the maximum possible operating periods at 10 and 62 days for the falling hydraulic head and continuous hydraulic head respectively. Further analysis revealed that falling hydraulic head operation would require 21% more aeration to maintain a consistent crossflow velocity than continuous operation and would rely on pumping for full permeate withdrawal 80% earlier. This study concluded that further optimisation would be required to make this technology technically and economically viable.

Identifying factors that predict the choice and success rate of radial artery catheterisation in contemporary real world cardiology practice: a sub-analysis of the PREVAIL study data.

PubMed

Pristipino, Christian; Roncella, Adriana; Trani, Carlo; Nazzaro, Marco S; Berni, Andrea; Di Sciascio, Germano; Sciahbasi, Alessandro; Musarò, Salvatore Donato; Mazzarotto, Pietro; Gioffrè, Gaetano; Speciale, Giulio

2010-06-01

To assess: the reasons behind an operator choosing to perform radial artery catheterisation (RAC) as against femoral arterial catheterisation, and to explore why RAC may fail in the real world. A pre-determined analysis of PREVAIL study database was performed. Relevant data were collected in a prospective, observational survey of 1,052 consecutive patients undergoing invasive cardiovascular procedures at nine Italian hospitals over a one month observation period. By multivariate analysis, the independent predictors of RAC choice were having the procedure performed: (1) at a high procedural volume centre; and (2) by an operator who performs a high volume of radial procedures; clinical variables played no statistically significant role. RAC failure was predicted independently by (1) a lower operator propensity to use RAC; and (2) the presence of obstructive peripheral artery disease. A 10-fold lower rate of RAC failure was observed among operators who perform RAC for > 85% of their personal caseload than among those who use RAC < 25% of the time (3.8% vs. 33.0%, respectively); by receiver operator characteristic (ROC) analysis, no threshold value for operator RAC volume predicted RAC failure. A routine RAC in all-comers is superior to a selective strategy in terms of feasibility and success rate.

A Clifford analysis approach to superspace

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

Bie, H. de; Sommen, F.

A new framework for studying superspace is given, based on methods from Clifford analysis. This leads to the introduction of both orthogonal and symplectic Clifford algebra generators, allowing for an easy and canonical introduction of a super-Dirac operator, a super-Laplace operator and the like. This framework is then used to define a super-Hodge coderivative, which, together with the exterior derivative, factorizes the Laplace operator. Finally both the cohomology of the exterior derivative and the homology of the Hodge operator on the level of polynomial-valued super-differential forms are studied. This leads to some interesting graphical representations and provides a better insightmore » in the definition of the Berezin-integral.« less

IUS/TUG orbital operations and mission support study. Volume 3: Space tug operations

NASA Technical Reports Server (NTRS)

1975-01-01

A study was conducted to develop space tug operational concepts and baseline operations plan, and to provide cost estimates for space tug operations. Background data and study results are presented along with a transition phase analysis (the transition from interim upper state to tug operations). A summary is given of the tug operational and interface requirements with emphasis on the on-orbit checkout requirements, external interface operational requirements, safety requirements, and system operational interface requirements. Other topics discussed include reference missions baselined for the tug and details for the mission functional flows and timelines derived for the tug mission, tug subsystems, tug on-orbit operations prior to the tug first burn, spacecraft deployment and retrieval by the tug, operations centers, mission planning, potential problem areas, and cost data.

Waterworks Operator Training Manual.

ERIC Educational Resources Information Center

Missouri Univ., Columbia. Instructional Materials Lab.

Sixteen self-study waterworks operators training modules are provided. Module titles are the following: basic mathematics, basic chemistry, analysis procedures, microbiology, basic electricity, hydraulics, chlorination, plant operation, surface water, ground water, pumps, cross connections, distribution systems, safety, public relations, and…

Operator induced variability in left ventricular measurements with cardiovascular magnetic resonance is improved after training.

PubMed

Karamitsos, Theodoros D; Hudsmith, Lucy E; Selvanayagam, Joseph B; Neubauer, Stefan; Francis, Jane M

2007-01-01

Accurate and reproducible measurement of left ventricular (LV) mass and function is a significant strength of Cardiovascular Magnetic Resonance (CMR). Reproducibility and accuracy of these measurements is usually reported between experienced operators. However, an increasing number of inexperienced operators are now training in CMR and are involved in post-processing analysis. The aim of the study was to assess the interobserver variability of the manual planimetry of LV contours amongst two experienced and six inexperienced operators before and after a two months training period. Ten healthy normal volunteers (5 men, mean age 34+/-14 years) comprised the study population. LV volumes, mass, and ejection fraction were manually evaluated using Argus software (Siemens Medical Solutions, Erlangen, Germany) for each subject, once by the two experienced and twice by the six inexperienced operators. The mean values of experienced operators were considered the reference values. The agreement between operators was evaluated by means of Bland-Altman analysis. Training involved standardized data acquisition, simulated off-line analysis and mentoring. The trainee operators demonstrated improvement in the measurement of all the parameters compared to the experienced operators. The mean ejection fraction variability improved from 7.2% before training to 3.7% after training (p=0.03). The parameter in which the trainees showed the least improvement was LV mass (from 7.7% to 6.7% after training). The basal slice selection and contour definition were the main sources of errors. An intensive two month training period significantly improved the accuracy of LV functional measurements. Adequate training of new CMR operators is of paramount importance in our aim to maintain the accuracy and high reproducibility of CMR in LV function analysis.

An Analysis of Delay and Travel Times at Sao Paulo International Airport (AISP/GRU): Planning Based on Simulation Model

NASA Technical Reports Server (NTRS)

Santana, Erico Soriano Martins; Mueller, Carlos

2003-01-01

The occurrence of flight delays in Brazil, mostly verified at the ground (airfield), is responsible for serious disruptions at the airport level but also for the unchaining of problems in all the airport system, affecting also the airspace. The present study develops an analysis of delay and travel times at Sao Paulo International Airport/ Guarulhos (AISP/GRU) airfield based on simulation model. Different airport physical and operational scenarios had been analyzed by means of simulation. SIMMOD Plus 4.0, the computational tool developed to represent aircraft operation in the airspace and airside of airports, was used to perform these analysis. The study was mainly focused on aircraft operations on ground, at the airport runway, taxi-lanes and aprons. The visualization of the operations with increasing demand facilitated the analyses. The results generated in this work certify the viability of the methodology, they also indicated the solutions capable to solve the delay problem by travel time analysis, thus diminishing the costs for users mainly airport authority. It also indicated alternatives for airport operations, assisting the decision-making process and in the appropriate timing of the proposed changes in the existing infrastructure.

Risk analysis theory applied to fishing operations: A new approach on the decision-making problem

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

Cunha, J.C.S.

1994-12-31

In the past the decisions concerning whether to continue or interrupt a fishing operation were based primarily on the operator`s previous experience. This procedure often led to wrong decisions and unnecessary loss of money and time. This paper describes a decision-making method based on risk analysis theory and previous operation results from a field under study. The method leads to more accurate decisions on a daily basis allowing the operator to verify each day of the operation if the decision being carried out is the one with the highest probability to conduct to the best economical result. An example ofmore » the method application is provided at the end of the paper.« less

Space Operations Center system analysis study extension. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1982-01-01

The analysis fo Space Operations Center (SOC) systems is summarized. Design considerations, configurations of the manned orbital space station, planned operational and research missions, and subsystem tradeoffs are considered. Integration into the space transportation system is discussed. A modular design concept permitting growth of the SOC as its functions are expanded is described. Additional considerations are special requirements for habitat modules, design modifications needed to operate in geosynchronous orbits, and use of the external tank for cryogenic propellant storage or as a pressurized hangar. A cost summary is presented.

The Effects of Massage Therapy on Pain and Anxiety after Surgery: A Systematic Review and Meta-Analysis.

PubMed

Kukimoto, Yukiko; Ooe, Noriko; Ideguchi, Norio

2017-12-01

Pain management is critical for patients after surgery, but current pain management methods are not always adequate. Massage therapy may be a therapeutic complementary therapy for pain. Many researchers have investigated the effects of massage therapy on post-operative pain, but there have been no systematic reviews and meta-analysis of its efficacy for post-operative patients. Our objective was to assess the effects of massage therapy on pain management among post-operative patients by conducting a systematic review and meta-analysis. The databases searched included MEDLINE, CINAHL, and the Cochrane Library's CENTRAL. To assess the effects of massage therapy on post-operative pain and anxiety, we performed a meta-analysis and calculated standardized mean difference with 95% CIs (Confidential Intervals) as a summary effect. Ten randomized controlled trials were selected (total sample size = 1,157). Meta-analysis was conducted using subgroup analysis. The effect of single dosage massage therapy on post-operative pain showed significant improvement (-0.49; 95% confidence intervals -0.64, -0.34; p < .00001) and low heterogeneity (p = .39, I 2 = 4%), sternal incisions showed significant improvement in pain (-0.68; -0.91, -0.46; p< .00001) and low heterogeneity (p = .76, I 2 = 0%). The anxiety subgroups showed substantial heterogeneity. The findings of this study revealed that massage therapy may alleviate post-operative pain, although there are limits on generalization of these findings due to low methodological quality in the reviewed studies. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Space construction system analysis. Part 2: Cost and programmatics

NASA Technical Reports Server (NTRS)

Vonflue, F. W.; Cooper, W.

1980-01-01

Cost and programmatic elements of the space construction systems analysis study are discussed. The programmatic aspects of the ETVP program define a comprehensive plan for the development of a space platform, the construction system, and the space shuttle operations/logistics requirements. The cost analysis identified significant items of cost on ETVP development, ground, and flight segments, and detailed the items of space construction equipment and operations.

NHEXAS PHASE I ARIZONA STUDY--LIST OF STANDARD OPERATING PROCEDURES

EPA Science Inventory

This document lists available protocols and SOPs for the NHEXAS Phase I Arizona study. It identifies protocols and SOPs for the following study components: (1) Sample collection and field operations, (2) Sample analysis, (3) General laboratory procedures, (4) Quality Assurance, (...

Space Operations Center System Analysis: Requirements for a Space Operations Center, revision A

NASA Technical Reports Server (NTRS)

Woodcock, G. R.

1982-01-01

The system and program requirements for a space operations center as defined by systems analysis studies are presented as a guide for future study and systems definition. Topics covered include general requirements for safety, maintainability, and reliability, service and habitat modules, the health maintenance facility; logistics modules; the docking tunnel; and subsystem requirements (structures, electrical power, environmental control/life support; extravehicular activity; data management; communications and tracking; docking/berthing; flight control/propulsion; and crew support). Facilities for flight support, construction, satellite and mission servicing, and fluid storage are included as well as general purpose support equipment.

Performance of the European System for Cardiac Operative Risk Evaluation II: a meta-analysis of 22 studies involving 145,592 cardiac surgery procedures.

PubMed

Guida, Pietro; Mastro, Florinda; Scrascia, Giuseppe; Whitlock, Richard; Paparella, Domenico

2014-12-01

A systematic review of the European System for Cardiac Operative Risk Evaluation (euroSCORE) II performance for prediction of operative mortality after cardiac surgery has not been performed. We conducted a meta-analysis of studies based on the predictive accuracy of the euroSCORE II. We searched the Embase and PubMed databases for all English-only articles reporting performance characteristics of the euroSCORE II. The area under the receiver operating characteristic curve, the observed/expected mortality ratio, and observed-expected mortality difference with their 95% confidence intervals were analyzed. Twenty-two articles were selected, including 145,592 procedures. Operative mortality occurred in 4293 (2.95%), whereas the expected events according to euroSCORE II were 4802 (3.30%). Meta-analysis of these studies provided an area under the receiver operating characteristic curve of 0.792 (95% confidence interval, 0.773-0.811), an estimated observed/expected ratio of 1.019 (95% confidence interval, 0.899-1.139), and observed-expected difference of 0.125 (95% confidence interval, -0.269 to 0.519). Statistical heterogeneity was detected among retrospective studies including less recent procedures. Subgroups analysis confirmed the robustness of combined estimates for isolated valve procedures and those combined with revascularization surgery. A significant overestimation of the euroSCORE II with an observed/expected ratio of 0.829 (95% confidence interval, 0.677-0.982) was observed in isolated coronary artery bypass grafting and a slight underestimation of predictions in high-risk patients (observed/expected ratio 1.253 and observed-expected difference 1.859). Despite the heterogeneity, the results from this meta-analysis show a good overall performance of the euroSCORE II in terms of discrimination and accuracy of model predictions for operative mortality. Validation of the euroSCORE II in prospective populations needs to be further studied for a continuous improvement of patients' risk stratification before cardiac surgery. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

There Can Be Only One: An Analysis of Operational Artists in Vietnam

DTIC Science & Technology

2017-05-05

elevated, in the case of the Vietnam comparative study here, to the theater commander. 6...factors in identifying the true Operational Artist in the Vietnam case study as well as future conflicts. This is where the creativity that defines...difference between successful and unsuccessful Operational Artists in the sense this monograph proposes. This is a comparative case study between GEN Paul

Centaur operations at the space station: Cost and transportation analysis

NASA Technical Reports Server (NTRS)

1988-01-01

A study was conducted to expand on the results of an initial study entitled Centaur Operations at the Space Station. The previous study developed technology demonstration missions (TDMs) that utilized the Centaur G-prime upper stage to advance OTV technologies required for accomodations and operations at the Space Station. An initial evaluation was performed of the cost to NASA for TDM implementation. Due to the potential for commercial communication satellite operation utilizing the TDM hardware, an evaluation of the Centaur's transportation potential was also performed.

Compendium of Operations Research and Economic Analysis Studies.

DTIC Science & Technology

1987-09-01

robots , conveyor belts, etc. are modeled as well. Simulation results indicate that the IMC design for receiving and packing is feasible from a system...Logistics Services Center (DLSC) operation. Benef its were evaluated through analysis of a sample of data from recipients as to the use being made of...Modernization of the DPSC Manufacturing Facility (August 1969) This study explored the feasibility of a proposal to air condition and modernize the

Orbital operations study. Volume 2: Interfacing activities analysis. Part 2: Structural and mechanical group

NASA Technical Reports Server (NTRS)

Mattson, H. L.; Gianformaggio, A.; Anderson, N. R.

1972-01-01

The activities of the structural and mechanical activity group of the orbital operations study project are discussed. Element interfaces, alternate approaches, design concepts, operational procedures, functional requirements, design influences, and approach selection are presented. The following areas are considered: (1) mating, (2) orbital assembly, (3) separation, EOS payload deployment, and EOS payload retraction.

Mathematical analysis of the 1D model and reconstruction schemes for magnetic particle imaging

NASA Astrophysics Data System (ADS)

Erb, W.; Weinmann, A.; Ahlborg, M.; Brandt, C.; Bringout, G.; Buzug, T. M.; Frikel, J.; Kaethner, C.; Knopp, T.; März, T.; Möddel, M.; Storath, M.; Weber, A.

2018-05-01

Magnetic particle imaging (MPI) is a promising new in vivo medical imaging modality in which distributions of super-paramagnetic nanoparticles are tracked based on their response in an applied magnetic field. In this paper we provide a mathematical analysis of the modeled MPI operator in the univariate situation. We provide a Hilbert space setup, in which the MPI operator is decomposed into simple building blocks and in which these building blocks are analyzed with respect to their mathematical properties. In turn, we obtain an analysis of the MPI forward operator and, in particular, of its ill-posedness properties. We further get that the singular values of the MPI core operator decrease exponentially. We complement our analytic results by some numerical studies which, in particular, suggest a rapid decay of the singular values of the MPI operator.

The Sensitivity of a Global Ocean Model to Wind Forcing: A Test Using Sea Level and Wind Observations from Satellites and Operational Analysis

NASA Technical Reports Server (NTRS)

Fu, L. L.; Chao, Y.

1997-01-01

Investigated in this study is the response of a global ocean general circulation model to forcing provided by two wind products: operational analysis from the National Center for Environmental Prediction (NCEP); observations made by the ERS-1 radar scatterometer.

Cognitive Pathways: Analysis of Students' Written Texts for Science Understanding

ERIC Educational Resources Information Center

Grimberg, Bruna Irene; Hand, Brian

2009-01-01

The purpose of this study was to reconstruct writers' reasoning process as reflected in their written texts. The codes resulting from the text analysis were related to cognitive operations, ranging from simple to more sophisticated ones. The sequence of the cognitive operations as the text unfolded represents the writer's cognitive pathway at the…

In-Flight Laboratory Analysis

NASA Technical Reports Server (NTRS)

Baumann, David; Perusek, Gail; Nelson, Emily; Krihak, Michael; Brown, Dan

2012-01-01

One-year study objectives align with HRP requirements. HRP requirements include measurement panels for research and medical operations - These measurement panels are distinctly different. Instrument requirements are defined - Power, volume and mass not quite a critical limitation as for medical operations (deep space exploration missions). One-year evaluation goals will lead HHC towards in-flight laboratory analysis capability.

LatMix 2011 and 2012 Dispersion Analysis

DTIC Science & Technology

2015-09-30

work included the airborne lidar operations as well as a substantial part of the field operations and analysis. A primary objective of our LatMix... lidar ) surveys of evolving dye experiments as a tool for studying submesoscale lateral dispersion. 2 Numerous papers by our group relating to the...drifter / lidar effort, however, there are additional aspects of the data and analysis that are beyond the scope of these already-in-progress

Shuttle user analysis (study 2.2). Volume 3: Business risk and value of operations in space (BRAVO). Part 5: Analysis of GSFC Earth Observation Satellite (EOS) system mission model using BRAVO techniques

NASA Technical Reports Server (NTRS)

1975-01-01

Cost comparisons were made between three modes of operation (expend, ground refurbish, and space resupply) for the Earth Observation System (EOS-B) to furnish data to NASA on alternative ways to use the shuttle/EOS. Results of the analysis are presented in tabular form.

Application of State Analysis and Goal-based Operations to a MER Mission Scenario

NASA Technical Reports Server (NTRS)

Morris, John Richard; Ingham, Michel D.; Mishkin, Andrew H.; Rasmussen, Robert D.; Starbird, Thomas W.

2006-01-01

State Analysis is a model-based systems engineering methodology employing a rigorous discovery process which articulates operations concepts and operability needs as an integrated part of system design. The process produces requirements on system and software design in the form of explicit models which describe the system behavior in terms of state variables and the relationships among them. By applying State Analysis to an actual MER flight mission scenario, this study addresses the specific real world challenges of complex space operations and explores technologies that can be brought to bear on future missions. The paper first describes the tools currently used on a daily basis for MER operations planning and provides an in-depth description of the planning process, in the context of a Martian day's worth of rover engineering activities, resource modeling, flight rules, science observations, and more. It then describes how State Analysis allows for the specification of a corresponding goal-based sequence that accomplishes the same objectives, with several important additional benefits.

Application of State Analysis and Goal-Based Operations to a MER Mission Scenario

NASA Technical Reports Server (NTRS)

Morris, J. Richard; Ingham, Michel D.; Mishkin, Andrew H.; Rasmussen, Robert D.; Starbird, Thomas W.

2006-01-01

State Analysis is a model-based systems engineering methodology employing a rigorous discovery process which articulates operations concepts and operability needs as an integrated part of system design. The process produces requirements on system and software design in the form of explicit models which describe the behavior of states and the relationships among them. By applying State Analysis to an actual MER flight mission scenario, this study addresses the specific real world challenges of complex space operations and explores technologies that can be brought to bear on future missions. The paper describes the tools currently used on a daily basis for MER operations planning and provides an in-depth description of the planning process, in the context of a Martian day's worth of rover engineering activities, resource modeling, flight rules, science observations, and more. It then describes how State Analysis allows for the specification of a corresponding goal-based sequence that accomplishes the same objectives, with several important additional benefits.

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--LIST OF STANDARD OPERATING PROCEDURES

EPA Science Inventory

This document lists available protocols and SOPs for the U.S.-Mexico Border Program study. It identifies protocols and SOPs for the following study components: (1) Sample collection and field operations, (2) Sample analysis, (3) General laboratory procedures, (4) Quality Assuranc...

Evaluation of short-duration unscheduled absences among transit operators : TriMet case study

DOT National Transportation Integrated Search

2009-09-01

This report analyzes factors contributing to short duration (one to three days) unscheduled absences among operators : at TriMet, the transit provider for the Portland, Oregon metropolitan region. The analysis draws on a wide array of : operator-spec...

Evaluation of short-duration, unscheduled absences among transit operators: TriMet case study.

DOT National Transportation Integrated Search

2009-09-01

This report analyzes factors contributing to short duration (one to three days) unscheduled absences among operators at TriMet, the transit provider for the Portland, Oregon metropolitan region. The analysis draws on a wide array of operator-specific...

Analysis of the potential benefits of larger trucks for U.S. businesses operating private fleets.

DOT National Transportation Integrated Search

2009-05-01

This study examines the current operational and economic performance of a sample of companies that operate private fleets and establishes a present-day baseline of transport productivity and efficiency. It also estimates how transportation performanc...

Characteristics of future air cargo demand and impact on aircraft development - A report on the Cargo/Logistic Airlift Systems Study /CLASS/ project

NASA Technical Reports Server (NTRS)

Whitehead, A. H., Jr.

1978-01-01

The considered study has been conducted to evaluate the future potential for an advanced air cargo transport. A current operations analysis is discussed, taking into account the traffic structure, modal cost comparisons, terminal operations, containerization, and institutional factors. Attention is also given to case studies, a demand forecast, and an advanced air cargo systems analysis. The effects of potential improvements on reducing costs are shown. Improvement to the current infrastructure can occur from 1978 to 1985 with off-the-shelf technology, which when combined with higher load factors for aircraft and containers, can provide up to a 16 percent reduction in total operating costs and a 15 percent rate reduction. The results of the analysis indicate that the proposed changes in the infrastructure and improved cargo loading efficiencies are as important to improving the airlines' financial posture as is the anticipated large dedicated cargo aircraft.

Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit 1. Volume 5: Analysis of core damage frequency from seismic events during mid-loop operations

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

Budnitz, R.J.; Davis, P.R.; Ravindra, M.K.

1994-08-01

In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1) and the other at Sandia National Laboratories studying a boiling water reactor (Grand Gulf). Both the Brookhaven and Sandia projects have examined only accidents initiated by internal plant faults--so-called ``internal initiators.`` This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling shutdown conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. Thismore » report covers the seismic analysis at Surry Unit 1. All of the many systems modeling assumptions, component non-seismic failure rates, and human error rates that were used in the internal-initiator study at Surry have been adopted here, so that the results of the two studies can be as comparable as possible. Both the Brookhaven study and this study examine only two shutdown plant operating states (POSs) during refueling outages at Surry, called POS 6 and POS 10, which represent mid-loop operation before and after refueling, respectively. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POSs 6 and 10. The results of the analysis are that the core-damage frequency of earthquake-initiated accidents during refueling outages in POS 6 and POS 10 is found to be low in absolute terms, less than 10{sup {minus}6}/year.« less

An Overview and Analysis of Journal Operations, Journal Publication Patterns, and Journal Impact in School Psychology and Related Fields

ERIC Educational Resources Information Center

Floyd, Randy G.; Cooley, Kathryn M.; Arnett, James E.; Fagan, Thomas K.; Mercer, Sterett H.; Hingle, Christine

2011-01-01

This article describes the results of three studies designed to understand better the journal operations, publishing practices, and impact of school psychology journals in recent years. The first study presents the results of a survey focusing on journal operations and peer-review practices that was completed by 61 journal editors of school…

SPICE for ESA Planetary Missions: geometry and visualization support to studies, operations and data analysis within your reach

NASA Astrophysics Data System (ADS)

Costa, Marc

2018-05-01

JUICE is a mission chosen in the framework of the Cosmic Vision 2015-2024 program of the SRE. JUICE will survey the Jovian system with a special focus on the three Galilean Moons. Currently the mission is under study activities during its Definition Phase. For this period the future mission scenarios are being studied by the Science Working Team (SWT). The Mission Analysis and Payload Support (MAPPS) and the Solar System Science Operations Laboratory (SOLab) tools are being used to provide active support to the SWT in synergy with other operational tools used in the Department in order to evaluate the feasibility of those scenarios. This contribution will outline the capabilities, synergies as well as use cases of the mentioned tools focusing on the support provided to JUICEís study phase on the study of its critical operational scenarios and the early developments of its Science Ground Segment demonstrating the added value that such a tool provides to planetary science missions.

Three-dimensional computer-aided human factors engineering analysis of a grafting robot.

PubMed

Chiu, Y C; Chen, S; Wu, G J; Lin, Y H

2012-07-01

The objective of this research was to conduct a human factors engineering analysis of a grafting robot design using computer-aided 3D simulation technology. A prototype tubing-type grafting robot for fruits and vegetables was the subject of a series of case studies. To facilitate the incorporation of human models into the operating environment of the grafting robot, I-DEAS graphic software was applied to establish individual models of the grafting robot in line with Jack ergonomic analysis. Six human models (95th percentile, 50th percentile, and 5th percentile by height for both males and females) were employed to simulate the operating conditions and working postures in a real operating environment. The lower back and upper limb stresses of the operators were analyzed using the lower back analysis (LBA) and rapid upper limb assessment (RULA) functions in Jack. The experimental results showed that if a leg space is introduced under the robot, the operator can sit closer to the robot, which reduces the operator's level of lower back and upper limbs stress. The proper environmental layout for Taiwanese operators for minimum levels of lower back and upper limb stress are to set the grafting operation at 23.2 cm away from the operator at a height of 85 cm and with 45 cm between the rootstock and scion units.

[The operative functioning of maternity hospital].

PubMed

2011-01-01

The analysis of operative functioning of maternity hospital is presented. The study results characterize the work loads, the level of professional qualification of medical personnel, the level of pathology of delivery demanding an operative invasion. The conditions of effective decision making in financial issues are discussed.

Applying analysis tools in planning for operations : case study #4 -- application of microsimulation in combination with travel demand models

DOT National Transportation Integrated Search

2009-09-01

More and more, transportation system operators are seeing the benefits of strengthening links between planning and operations. A critical element in improving transportation decision-making and the effectiveness of transportation systems related to o...

Applying analysis tools in planning for operations : case study #2 -- incorporating Highway Capacity Manual procedures into long-range transportation planning

DOT National Transportation Integrated Search

2009-09-01

More and more, transportation system operators are seeing the benefi ts of strengthening links between : planning and operations. A critical element in improving transportation decision-making and the effectiveness : of transportation systems related...

Multicriteria Decision-Making Approach with Hesitant Interval-Valued Intuitionistic Fuzzy Sets

PubMed Central

Peng, Juan-juan; Wang, Jian-qiang; Wang, Jing; Chen, Xiao-hong

2014-01-01

The definition of hesitant interval-valued intuitionistic fuzzy sets (HIVIFSs) is developed based on interval-valued intuitionistic fuzzy sets (IVIFSs) and hesitant fuzzy sets (HFSs). Then, some operations on HIVIFSs are introduced in detail, and their properties are further discussed. In addition, some hesitant interval-valued intuitionistic fuzzy number aggregation operators based on t-conorms and t-norms are proposed, which can be used to aggregate decision-makers' information in multicriteria decision-making (MCDM) problems. Some valuable proposals of these operators are studied. In particular, based on algebraic and Einstein t-conorms and t-norms, some hesitant interval-valued intuitionistic fuzzy algebraic aggregation operators and Einstein aggregation operators can be obtained, respectively. Furthermore, an approach of MCDM problems based on the proposed aggregation operators is given using hesitant interval-valued intuitionistic fuzzy information. Finally, an illustrative example is provided to demonstrate the applicability and effectiveness of the developed approach, and the study is supported by a sensitivity analysis and a comparison analysis. PMID:24983009

Follow and Assume: The Operational Reserve in Security, Stability, Reconstruction, and Transition Operations

DTIC Science & Technology

2007-06-15

the lack of any or all of these items in order to de -legitimize the occupation force and or its follow on civilian government in order to gain a...operations will be used to compare and contrast, rather than trying to develop new patterns and themes based on primary sources. Delimitations of this study...chapter 4, “Analysis and Interpretation.” Based upon this analysis, in chapter 5, “Conclusions and Recommendations,” the research will develop and

Study to determine the IFR operational profile and problems of the general aviation single pilot

NASA Technical Reports Server (NTRS)

Weislogel, G. S.

1983-01-01

General aviation single pilot operating under instrument flight rules (GA SPIFR) was studied. The objectives of the study were to (1) develop a GA SPIFR operational profile, (2) identify problems experienced by the GA SPIFR pilot, and (3) identify research tasks which have the potential for eliminating or reducing the severity of the problems. To obtain the information necessary to accomplish these objectives, a mail questionnaire survey of instrument rated pilots was conducted. The general aviation IFR single pilot operational profile and selected data analysis examples are presented.

Harmonic component detection: Optimized Spectral Kurtosis for operational modal analysis

NASA Astrophysics Data System (ADS)

Dion, J.-L.; Tawfiq, I.; Chevallier, G.

2012-01-01

This work is a contribution in the field of Operational Modal Analysis to identify the modal parameters of mechanical structures using only measured responses. The study deals with structural responses coupled with harmonic components amplitude and frequency modulated in a short range, a common combination for mechanical systems with engines and other rotating machines in operation. These harmonic components generate misleading data interpreted erroneously by the classical methods used in OMA. The present work attempts to differentiate maxima in spectra stemming from harmonic components and structural modes. The detection method proposed is based on the so-called Optimized Spectral Kurtosis and compared with others definitions of Spectral Kurtosis described in the literature. After a parametric study of the method, a critical study is performed on numerical simulations and then on an experimental structure in operation in order to assess the method's performance.

Cartographic Modeling: Computer-assisted Analysis of Spatially Defined Neighborhoods

NASA Technical Reports Server (NTRS)

Berry, J. K.; Tomlin, C. D.

1982-01-01

Cartographic models addressing a wide variety of applications are composed of fundamental map processing operations. These primitive operations are neither data base nor application-specific. By organizing the set of operations into a mathematical-like structure, the basis for a generalized cartographic modeling framework can be developed. Among the major classes of primitive operations are those associated with reclassifying map categories, overlaying maps, determining distance and connectivity, and characterizing cartographic neighborhoods. The conceptual framework of cartographic modeling is established and techniques for characterizing neighborhoods are used as a means of demonstrating some of the more sophisticated procedures of computer-assisted map analysis. A cartographic model for assessing effective roundwood supply is briefly described as an example of a computer analysis. Most of the techniques described have been implemented as part of the map analysis package developed at the Yale School of Forestry and Environmental Studies.

Matching food security analysis to context: the experience of the Somalia food security assessment unit.

PubMed

Hemrich, Günter

2005-06-01

This case study reviews the experience of the Somalia Food Security Assessment Unit (FSAU) of operating a food security information system in the context of a complex emergency. In particular, it explores the linkages between selected features of the protracted crisis environment in Somalia and conceptual and operational aspects of food security information work. The paper specifically examines the implications of context characteristics for the establishment and operations of the FSAU field monitoring component and for the interface with information users and their diverse information needs. It also analyses the scope for linking food security and nutrition analysis and looks at the role of conflict and gender analysis in food security assessment work. Background data on the food security situation in Somalia and an overview of some key features of the FSAU set the scene for the case study. The paper is targeted at those involved in designing, operating and funding food security information activities.

System Operations Studies : Feeder System Model. User's Manual.

DOT National Transportation Integrated Search

1982-11-01

The Feeder System Model (FSM) is one of the analytic models included in the System Operations Studies (SOS) software package developed for urban transit systems analysis. The objective of the model is to assign a proportion of the zone-to-zone travel...

Total ankle arthroplasty versus ankle arthrodesis for the treatment of end-stage ankle arthritis: a meta-analysis of comparative studies.

PubMed

Kim, Hyun Jung; Suh, Dong Hun; Yang, Jae Hyuk; Lee, Jin Woo; Kim, Hak Jun; Ahn, Hyeong Sik; Han, Seung Woo; Choi, Gi Won

2017-01-01

Total ankle arthroplasty (TAA) and ankle arthrodesis (AA) are the main surgical treatment options for end-stage ankle arthritis. Although the superiority of each modality remains debated, there remains a lack of high-quality evidence-based studies, such as randomized controlled clinical trials, and meta-analyses of comparative studies. We performed a meta-analysis of comparative studies to determine whether there is a significant difference between these two procedures in terms of (i) clinical scores and patient satisfaction, (ii) re-operations, and (iii) complications. We conducted a comprehensive search in the MEDLINE, EMBASE, and Cochrane library databases. Only retrospective or prospective comparative studies were included in this meta-analysis. The literature search, data extraction, and quality assessment were conducted by two independent reviewers. The primary outcomes were clinical scores and patient satisfaction. We also investigated the prevalence of complications and the re-operation rate. Ten comparative studies were included (four prospective and six retrospective studies). There were no significant differences between the two procedures in the American Orthopaedic Foot and Ankle Society ankle-hindfoot score, Short Form-36 physical component summary and mental component summary scores, visual analogue scale for pain, and patient satisfaction rate. The risk of re-operation and major surgical complications were significantly increased in the TAA group. The meta-analysis revealed that TAA and AA could achieve similar clinical outcomes, whereas the incidence of re-operation and major surgical complication was significantly increased in TAA. Further studies of high methodological quality with long-term follow-up are required to confirm our conclusions.

Safety analysis in test facility design

NASA Astrophysics Data System (ADS)

Valk, A.; Jonker, R. J.

1990-09-01

The application of safety analysis techniques as developed in, for example nuclear and petrochemical industry, can be very beneficial in coping with the increasing complexity of modern test facility installations and their operations. To illustrate the various techniques available and their phasing in a project, an overview of the most commonly used techniques is presented. Two case studies are described: the hazard and operability study techniques and safety zoning in relation to the possible presence of asphyxiating atmospheres.

Operations analysis (study 2.1). Contingency analysis. [of failure modes anticipated during space shuttle upper stage planning

NASA Technical Reports Server (NTRS)

1974-01-01

Future operational concepts for the space transportation system were studied in terms of space shuttle upper stage failure contingencies possible during deployment, retrieval, or space servicing of automated satellite programs. Problems anticipated during mission planning were isolated using a modified 'fault tree' technique, normally used in safety analyses. A comprehensive space servicing hazard analysis is presented which classifies possible failure modes under the catagories of catastrophic collision, failure to rendezvous and dock, servicing failure, and failure to undock. The failure contingencies defined are to be taken into account during design of the upper stage.

Specialized data analysis of SSME and advanced propulsion system vibration measurements

NASA Technical Reports Server (NTRS)

Coffin, Thomas; Swanson, Wayne L.; Jong, Yen-Yi

1993-01-01

The basic objectives of this contract were to perform detailed analysis and evaluation of dynamic data obtained during Space Shuttle Main Engine (SSME) test and flight operations, including analytical/statistical assessment of component dynamic performance, and to continue the development and implementation of analytical/statistical models to effectively define nominal component dynamic characteristics, detect anomalous behavior, and assess machinery operational conditions. This study was to provide timely assessment of engine component operational status, identify probable causes of malfunction, and define feasible engineering solutions. The work was performed under three broad tasks: (1) Analysis, Evaluation, and Documentation of SSME Dynamic Test Results; (2) Data Base and Analytical Model Development and Application; and (3) Development and Application of Vibration Signature Analysis Techniques.

Grid Resolution Study over Operability Space for a Mach 1.7 Low Boom External Compression Inlet

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.

2014-01-01

This paper presents a statistical methodology whereby the probability limits associated with CFD grid resolution of inlet flow analysis can be determined which provide quantitative information on the distribution of that error over the specified operability range. The objectives of this investigation is to quantify the effects of both random (accuracy) and systemic (biasing) errors associated with grid resolution in the analysis of the Lockheed Martin Company (LMCO) N+2 Low Boom external compression supersonic inlet. The study covers the entire operability space as defined previously by the High Speed Civil Transport (HSCT) High Speed Research (HSR) program goals. The probability limits in terms of a 95.0% confidence interval on the analysis data were evaluated for four ARP1420 inlet metrics, namely (1) total pressure recovery (PFAIP), (2) radial hub distortion (DPH/P), (3) ) radial tip distortion (DPT/P), and (4) ) circumferential distortion (DPC/P). In general, the resulting +/-0.95 delta Y interval was unacceptably large in comparison to the stated goals of the HSCT program. Therefore, the conclusion was reached that the "standard grid" size was insufficient for this type of analysis. However, in examining the statistical data, it was determined that the CFD analysis results at the outer fringes of the operability space were the determining factor in the measure of statistical uncertainty. Adequate grids are grids that are free of biasing (systemic) errors and exhibit low random (precision) errors in comparison to their operability goals. In order to be 100% certain that the operability goals have indeed been achieved for each of the inlet metrics, the Y+/-0.95 delta Y limit must fall inside the stated operability goals. For example, if the operability goal for DPC/P circumferential distortion is =0.06, then the forecast Y for DPC/P plus the 95% confidence interval on DPC/P, i.e. +/-0.95 delta Y, must all be less than or equal to 0.06.

Study of aircraft in intraurban transportation systems

NASA Technical Reports Server (NTRS)

Stout, E. G.

1972-01-01

A systems analysis was conducted to define the technical economic and operational characteristics of an aircraft transportation system for short-range intracity commutor operations. The analysis was for 1975 and 1985 in the seven county, Detroit, Michigan area. STOL and VTOL aircraft were studied in sizes from 40 to 120 passengers. The preferred vehicle for the Detroit area was the deflected slipstream STOL. Since the study was parametric in nature, it is applicable to generalization, and it was concluded that a feasible intraurban air transportation system could be developed in many viable situations.

Developing an Operator Training Program.

ERIC Educational Resources Information Center

Wubbena, Robert L.

1978-01-01

The study reported is a nationwide comprehensive analysis of the availability of training and the problems associated with the development of effective state programs for operators of water supply and wastewater facilities. (CS)

Crew interface analysis: Selected articles on space human factors research, 1987 - 1991

NASA Technical Reports Server (NTRS)

Bagian, Tandi (Compiler)

1993-01-01

As part of the Flight Crew Support Division at NASA, the Crew Interface Analysis Section is dedicated to the study of human factors in the manned space program. It assumes a specialized role that focuses on answering operational questions pertaining to NASA's Space Shuttle and Space Station Freedom Programs. One of the section's key contributions is to provide knowledge and information about human capabilities and limitations that promote optimal spacecraft and habitat design and use to enhance crew safety and productivity. The section provides human factors engineering for the ongoing missions as well as proposed missions that aim to put human settlements on the Moon and Mars. Research providing solutions to operational issues is the primary objective of the Crew Interface Analysis Section. The studies represent such subdisciplines as ergonomics, space habitability, man-computer interaction, and remote operator interaction.

Preparing GMAT for Operational Maneuver Planning of the Advanced Composition Explorer (ACE)

NASA Technical Reports Server (NTRS)

Qureshi, Rizwan Hamid; Hughes, Steven P.

2014-01-01

The General Mission Analysis Tool (GMAT) is an open-source space mission design, analysis and trajectory optimization tool. GMAT is developed by a team of NASA, private industry, public and private contributors. GMAT is designed to model, optimize and estimate spacecraft trajectories in flight regimes ranging from low Earth orbit to lunar applications, interplanetary trajectories and other deep space missions. GMAT has also been flight qualified to support operational maneuver planning for the Advanced Composition Explorer (ACE) mission. ACE was launched in August, 1997 and is orbiting the Sun-Earth L1 libration point. The primary science objective of ACE is to study the composition of both the solar wind and the galactic cosmic rays. Operational orbit determination, maneuver operations and product generation for ACE are conducted by NASA Goddard Space Flight Center (GSFC) Flight Dynamics Facility (FDF). This paper discusses the entire engineering lifecycle and major operational certification milestones that GMAT successfully completed to obtain operational certification for the ACE mission. Operational certification milestones such as gathering of the requirements for ACE operational maneuver planning, gap analysis, test plans and procedures development, system design, pre-shadow operations, training to FDF ACE maneuver planners, shadow operations, Test Readiness Review (TRR) and finally Operational Readiness Review (ORR) are discussed. These efforts have demonstrated that GMAT is flight quality software ready to support ACE mission operations in the FDF.

Fully-Integrated Simulation of Conjunctive Use from Field to Basin Scales: Development of a Surface Water Operations Module for MODFLOW-OWHM

NASA Astrophysics Data System (ADS)

Ferguson, I. M.; Boyce, S. E.; Hanson, R. T.; Llewellyn, D.

2014-12-01

It is well established that groundwater pumping affects surface-water availability by intercepting groundwater that would otherwise discharge to streams and/or by increasing seepage from surface-water channels. Conversely, surface-water management operations effect groundwater availability by altering the timing, location, and quantity of groundwater recharge and demand. Successful conjunctive use may require analysis with an integrated approach that accounts for the many interactions and feedbacks between surface-water and groundwater availability and their joint management. In order to improve simulation and analysis of conjunctive use, Bureau of Reclamation and USGS are collaborating to develop a surface-water operations module within MODFLOW One Water Hydrologic Flow Model (MF-OWHM), a new version of the USGS Modular Groundwater Flow Model (MODFLOW). Here we describe the development and application of the surface-water operations module. We provide an overview of the conceptual approach used to simulate surface-water operations—including surface-water storage, allocation, release, diversion, and delivery on monthly to seasonal time frames—in a fully-integrated manner. We then present results from a recent case study analysis of the Rio Grande Project, a large-scale irrigation project located in New Mexico and Texas, under varying surface-water operations criteria and climate conditions. Case study results demonstrate the importance of integrated hydrologic simulation of surface water and groundwater operations in analysis and management of conjunctive-use systems.

Evidence based medicine and surgical approaches for colon cancer: evidences, benefits and limitations of the laparoscopic vs open resection.

PubMed

Lorenzon, Laura; La Torre, Marco; Ziparo, Vincenzo; Montebelli, Francesco; Mercantini, Paolo; Balducci, Genoveffa; Ferri, Mario

2014-04-07

To report a meta-analysis of the studies that compared the laparoscopic with the open approach for colon cancer resection. Forty-seven manuscripts were reviewed, 33 of which employed for meta-analysis according to the PRISMA guidelines. The results were differentiated according to the study design (prospective randomized trials vs case-control series) and according to the tumor's location. Outcome measures included: (1) short-term results (operating times, blood losses, bowel function recovery, post-operative pain, return to the oral intake, complications and hospital stay); (2) oncological adequateness (number of nodes harvested in the surgical specimens); and (3) long-term results (including the survivals' rates and incidence of incisional hernias) and (4) costs. Meta-analysis of trials provided evidences in support of the laparoscopic procedures for a several short-term outcomes including: a lower blood loss, an earlier recovery of the bowel function, an earlier return to the oral intake, a shorter hospital stay and a lower morbidity rate. Opposite the operating time has been confirmed shorter in open surgery. The same trend has been reported investigating case-control series and cancer by sites, even though there are some concerns regarding the power of the studies in this latter field due to the small number of trials and the small sample of patients enrolled. The two approaches were comparable regarding the mean number of nodes harvested and long-term results, even though these variables were documented reviewing the literature but were not computable for meta-analysis. The analysis of the costs documented lower costs for the open surgery, however just few studies investigated the incidence of post-operative hernias. Laparoscopy is superior for the majority of short-term results. Future studies should better differentiate these approaches on the basis of tumors' location and the post-operative hernias.

Validation of a digital audio recording method for the objective assessment of cough in the horse.

PubMed

Duz, M; Whittaker, A G; Love, S; Parkin, T D H; Hughes, K J

2010-10-01

To validate the use of digital audio recording and analysis for quantification of coughing in horses. Part A: Nine simultaneous digital audio and video recordings were collected individually from seven stabled horses over a 1 h period using a digital audio recorder attached to the halter. Audio files were analysed using audio analysis software. Video and audio recordings were analysed for cough count and timing by two blinded operators on two occasions using a randomised study design for determination of intra-operator and inter-operator agreement. Part B: Seventy-eight hours of audio recordings obtained from nine horses were analysed once by two blinded operators to assess inter-operator repeatability on a larger sample. Part A: There was complete agreement between audio and video analyses and inter- and intra-operator analyses. Part B: There was >97% agreement between operators on number and timing of 727 coughs recorded over 78 h. The results of this study suggest that the cough monitor methodology used has excellent sensitivity and specificity for the objective assessment of cough in horses and intra- and inter-operator variability of recorded coughs is minimal. Crown Copyright 2010. Published by Elsevier India Pvt Ltd. All rights reserved.

Study of short-haul aircraft operating economics. Phase 2: An analysis of the impact of jet modernization on local service airline operating costs

NASA Technical Reports Server (NTRS)

Andrastek, D. A.

1976-01-01

The objectives of this phase of the study were (1) to assess the 10 year operating cost trends of the local service airlines operating in the 1965 through 1974 period, (2) to glean from these trends the technological and operational parameters which were impacted most significantly by the transition to newer pure jet, short haul transports, and effected by changing fuel prices and cost of living indices, and (3) to develop, construct, and evaluate an operating cost forecasting model which would incorporate those factors which best predicted airline total operating cost behavior over that 10-year period.

Solar power satellite. System definition study. Part 1, volume 3: Construction, transportation and cost analyses

NASA Technical Reports Server (NTRS)

1977-01-01

Concepts developed for both LEO and GEO construction of photovoltaic and thermal engine satellites are analyzed. Topics discussed include: satellite construction; crew scheduling; crew jobs and organizations; operator productivity rating; constructability rating; transportation systems for cargo launch, refueling operations, personnel transport, and orbit transfer; collision analysis, cost analysis, and radiation evironment and effects.

Atmospheric statistics for aerospace vehicle operations

NASA Technical Reports Server (NTRS)

Smith, O. E.; Batts, G. W.

1993-01-01

Statistical analysis of atmospheric variables was performed for the Shuttle Transportation System (STS) design trade studies and the establishment of launch commit criteria. Atmospheric constraint statistics have been developed for the NASP test flight, the Advanced Launch System, and the National Launch System. The concepts and analysis techniques discussed in the paper are applicable to the design and operations of any future aerospace vehicle.

Exploring Operational Test and Evaluation of Unmanned Aircraft Systems: A Qualitative Case Study

NASA Astrophysics Data System (ADS)

Saliceti, Jose A.

The purpose of this qualitative case study was to explore and identify strategies that may potentially remedy operational test and evaluation procedures used to evaluate Unmanned Aircraft Systems (UAS) technology. The sample for analysis consisted of organizations testing and evaluating UASs (e.g., U.S. Air Force, U.S. Navy, U.S. Army, U.S. Marine Corps, U.S. Coast Guard, and Customs Border Protection). A purposeful sampling technique was used to select 15 subject matter experts in the field of operational test and evaluation of UASs. A questionnaire was provided to participants to construct a descriptive and robust research. Analysis of responses revealed themes related to each research question. Findings revealed operational testers utilized requirements documents to extrapolate measures for testing UAS technology and develop critical operational issues. The requirements documents were (a) developed without the contribution of stakeholders and operational testers, (b) developed with vague or unrealistic measures, and (c) developed without a systematic method to derive requirements from mission tasks. Four approaches are recommended to develop testable operational requirements and assist operational testers: (a) use a mission task analysis tool to derive requirements for mission essential tasks for the system, (b) exercise collaboration among stakeholders and testers to ensure testable operational requirements based on mission tasks, (c) ensure testable measures are used in requirements documents, and (d) create a repository list of critical operational issues by mission areas. The preparation of operational test and evaluation processes for UAS technology is not uniform across testers. The processes in place are not standardized, thus test plan preparation and reporting are different among participants. A standard method to prepare and report UAS technology should be used when preparing and reporting on UAS technology. Using a systematic process, such as mission-based test design, resonated among participants as an analytical method to link UAS mission tasks and measures of performance to the capabilities of the system under test when developing operational test plans. Further research should examine system engineering designs for system requirements traceability matrix of mission tasks and subtasks while using an analysis tool that adequately evaluates UASs with an acceptable level of confidence in the results.

Design study of shaft face seal with self-acting lift augmentation. 4: Force balance

NASA Technical Reports Server (NTRS)

Ludwig, L. P.; Zuk, J.; Johnson, R. L.

1972-01-01

A method for predicting the operating film thickness of self-acting seals is described. The analysis considers a 16.76-cm mean diameter seal that is typical of large gas turbines for aircraft. Four design points were selected to cover a wide range of operation for advanced engines. This operating range covered sliding speeds of 61 to 153 m/sec, sealed pressures of 45 to 217 N/sq cm abs, and gas temperatures of 311 to 977 K. The force balance analysis revealed that the seal operated without contact over the operating range with gas film thicknesses ranging between 0.00046 to 0.00119 cm, and with gas leakage rates between 0.01 to 0.39 scmm.

Fuel freeze-point investigations. Final report, September 1982-March 1984

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

Desmarais, L.A.; Tolle, F.F.

1984-07-01

The objective of this program was to conduct a detailed assessment of the low-temperature environment to which USAF aircraft are exposed for the purpose of defining a maximum acceptable fuel freeze-point and also to define any operational changes required with the use of a high freeze-point fuel. A previous study of B-52, C-141, and KC-135 operational missions indicated that the -58 C freeze point specification was too conservative. Based on recommendations resulting from the previous program, several improvements in the method of analysis were made, such as: expansion of the atmospheric temperature data base, the addition of ground temperature analysis,more » the addition of fuel-freezing analysis to the one-dimensional fuel-temperature computer program, and the examination of heat transfer in external fuel tanks, such as pylon or tip tanks. The B-52, C-141, and KC-135 mission were analyzed again, along with the operational missions of two tactical airplanes, the A-10 and F-15; -50C was determined to be the maximum allowable freeze point for a general-purpose USAF aviation turbine fuel. Higher freeze points can be tolerated if the probability of operational interference is acceptably low or if operational changes can be made. Study of atmospheric temperatures encountered for the missions of the five-study aircraft indicates that a maximum freeze point of -48 C would not likely create any operational difficulties in Northern Europe.« less

Analysis of risk factors for postoperative morbidity in perforated peptic ulcer.

PubMed

Kim, Jae-Myung; Jeong, Sang-Ho; Lee, Young-Joon; Park, Soon-Tae; Choi, Sang-Kyung; Hong, Soon-Chan; Jung, Eun-Jung; Ju, Young-Tae; Jeong, Chi-Young; Ha, Woo-Song

2012-03-01

Emergency operations for perforated peptic ulcer are associated with a high incidence of postoperative complications. While several studies have investigated the impact of perioperative risk factors and underlying diseases on the postoperative morbidity after abdominal surgery, only a few have analyzed their role in perforated peptic ulcer disease. The purpose of this study was to determine any possible associations between postoperative morbidity and comorbid disease or perioperative risk factors in perforated peptic ulcer. In total, 142 consecutive patients, who underwent surgery for perforated peptic ulcer, at a single institution, between January 2005 and October 2010 were included in this study. The clinical data concerning the patient characteristics, operative methods, and complications were collected retrospectively. The postoperative morbidity rate associated with perforated peptic ulcer operations was 36.6% (52/142). Univariate analysis revealed that a long operating time, the open surgical method, age (≥60), sex (female), high American Society of Anesthesiologists (ASA) score and presence of preoperative shock were significant perioperative risk factors for postoperative morbidity. Significant comorbid risk factors included hypertension, diabetes mellitus and pulmonary disease. Multivariate analysis revealed a long operating time, the open surgical method, high ASA score and the presence of preoperative shock were all independent risk factors for the postoperative morbidity in perforated peptic ulcer. A high ASA score, preoperative shock, open surgery and long operating time of more than 150 minutes are high risk factors for morbidity. However, there is no association between postoperative morbidity and comorbid disease in patients with a perforated peptic ulcer.

Space shuttle/payload interface analysis. Volume 4: Business Risk and Value of Operations in Space (BRAVO). Part 1: Summary

NASA Technical Reports Server (NTRS)

1974-01-01

Background information is provided which emphasizes the philosophy behind analytical techniques used in the business risk and value of operations in space (BRAVO) study. The focus of the summary is on the general approach, operation of the procedures, and the status of the study. For Vol. 1, see N74-12493; for Vol. 2, see N74-14530.

Small-scale nuclear reactors for remote military operations: opportunities and challenges

DTIC Science & Technology

2015-08-25

study – Report was published in March 2011  CNA study identified challenges to deploy small modular reactors (SMRs) at a base – Identified First-of...forward operating bases. The availability of deployable, cost-effective, regulated, and secure small modular reactors with a modest output electrical...defense committees on the challenges, operational requirements, constraints, cost, and life cycle analysis for a small modular reactor of less than 10

Computational analysis of aircraft pressure relief doors

NASA Astrophysics Data System (ADS)

Schott, Tyler

Modern trends in commercial aircraft design have sought to improve fuel efficiency while reducing emissions by operating at higher pressures and temperatures than ever before. Consequently, greater demands are placed on the auxiliary bleed air systems used for a multitude of aircraft operations. The increased role of bleed air systems poses significant challenges for the pressure relief system to ensure the safe and reliable operation of the aircraft. The core compartment pressure relief door (PRD) is an essential component of the pressure relief system which functions to relieve internal pressure in the core casing of a high-bypass turbofan engine during a burst duct over-pressurization event. The successful modeling and analysis of a burst duct event are imperative to the design and development of PRD's to ensure that they will meet the increased demands placed on the pressure relief system. Leveraging high-performance computing coupled with advances in computational analysis, this thesis focuses on a comprehensive computational fluid dynamics (CFD) study to characterize turbulent flow dynamics and quantify the performance of a core compartment PRD across a range of operating conditions and geometric configurations. The CFD analysis was based on a compressible, steady-state, three-dimensional, Reynolds-averaged Navier-Stokes approach. Simulations were analyzed, and results show that variations in freestream conditions, plenum environment, and geometric configurations have a non-linear impact on the discharge, moment, thrust, and surface temperature characteristics. The CFD study revealed that the underlying physics for this behavior is explained by the interaction of vortices, jets, and shockwaves. This thesis research is innovative and provides a comprehensive and detailed analysis of existing and novel PRD geometries over a range of realistic operating conditions representative of a burst duct over-pressurization event. Further, the study provides aircraft manufacturers with valuable insight into the impact that operating conditions and geometric configurations have on PRD performance and how the information can be used to assist future research and development of PRD design.

Synchronous in-field application of life-detection techniques in planetary analog missions

NASA Astrophysics Data System (ADS)

Amador, Elena S.; Cable, Morgan L.; Chaudry, Nosheen; Cullen, Thomas; Gentry, Diana; Jacobsen, Malene B.; Murukesan, Gayathri; Schwieterman, Edward W.; Stevens, Adam H.; Stockton, Amanda; Yin, Chang; Cullen, David C.; Geppert, Wolf

2015-02-01

Field expeditions that simulate the operations of robotic planetary exploration missions at analog sites on Earth can help establish best practices and are therefore a positive contribution to the planetary exploration community. There are many sites in Iceland that possess heritage as planetary exploration analog locations and whose environmental extremes make them suitable for simulating scientific sampling and robotic operations. We conducted a planetary exploration analog mission at two recent lava fields in Iceland, Fimmvörðuháls (2010) and Eldfell (1973), using a specially developed field laboratory. We tested the utility of in-field site sampling down selection and tiered analysis operational capabilities with three life detection and characterization techniques: fluorescence microscopy (FM), adenine-triphosphate (ATP) bioluminescence assay, and quantitative polymerase chain reaction (qPCR) assay. The study made use of multiple cycles of sample collection at multiple distance scales and field laboratory analysis using the synchronous life-detection techniques to heuristically develop the continuing sampling and analysis strategy during the expedition. Here we report the operational lessons learned and provide brief summaries of scientific data. The full scientific data report will follow separately. We found that rapid in-field analysis to determine subsequent sampling decisions is operationally feasible, and that the chosen life detection and characterization techniques are suitable for a terrestrial life-detection field mission. In-field analysis enables the rapid obtainment of scientific data and thus facilitates the collection of the most scientifically relevant samples within a single field expedition, without the need for sample relocation to external laboratories. The operational lessons learned in this study could be applied to future terrestrial field expeditions employing other analytical techniques and to future robotic planetary exploration missions.

Feasibility Analysis of UAV Technology to Improve Tactical Surveillance in South Korea’s Rear Area Operations

DTIC Science & Technology

2017-03-01

determine the optimum required operational capability of the unmanned aerial vehicles to support Korean rear area operations. We use Map Aware Non ...area operations. Through further experimentations and analyses, we were able to find the optimum characteristics of an improved unmanned aerial...operations. We use Map Aware Non -Uniform Automata, an agent-based simulation software platform for computational experiments. The study models a scenario

Improving multi-objective reservoir operation optimization with sensitivity-informed dimension reduction

NASA Astrophysics Data System (ADS)

Chu, J.; Zhang, C.; Fu, G.; Li, Y.; Zhou, H.

2015-08-01

This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed method dramatically reduces the computational demands required for attaining high-quality approximations of optimal trade-off relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed dimension reduction and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform dimension reduction of optimization problems when solving complex multi-objective reservoir operation problems.

Improving multi-objective reservoir operation optimization with sensitivity-informed problem decomposition

NASA Astrophysics Data System (ADS)

Chu, J. G.; Zhang, C.; Fu, G. T.; Li, Y.; Zhou, H. C.

2015-04-01

This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce the computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed problem decomposition dramatically reduces the computational demands required for attaining high quality approximations of optimal tradeoff relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed problem decomposition and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform problem decomposition when solving the complex multi-objective reservoir operation problems.

Feasibility study of modern airships, phase 1. Volume 3: Historical overview (task 1)

NASA Technical Reports Server (NTRS)

Faurote, G. L.

1975-01-01

The history of lighter-than-air vehicles is reviewed in terms of providing a background for the mission analysis and parametric analysis tasks. Data from past airships and airship operations are presented in the following areas: (1) parameterization of design characteristics; (2) markets, missions, costs, and operating procedures, (3) indices of efficiency for comparison; (4) identification of critical design and operational characteristics; and (5) definition of the 1930 state-of-the-art and the 1974 state-of-the-art from a technical and economic standpoint.

The workload book: Assessment of operator workload to engineering systems

NASA Technical Reports Server (NTRS)

Gopher, D.

1983-01-01

The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.

36 CFR 292.18 - Mineral resources.

Code of Federal Regulations, 2010 CFR

2010-07-01

...; provided, that an operating plan is not required for— (1) Operations which only involve vehicular travel on... of more than 100 pounds of material for analysis and study, provided the Area Ranger has prior notice of such activities; or (4) The evaluation and study of existing underground mine workings not...

Controller and pilot error in airport operations : a review of previous research and analysis of safety data

DOT National Transportation Integrated Search

2001-01-01

The purpose of this study was to examine controller and pilot errors in airport operations to identify potential tower remedies. The : first part of the report contains a review of the literature of studies conducted of tower operationsand of efforts...

Sankofan socio-ethical reflections: the Tuskegee University National Bioethics Center's decade of operation, 1999-2009.

PubMed

Earl, Riggins R

2010-08-01

Primarily, this is a Sankofan socio-ethical analysis of the moral foundation of the Tuskegee University National Bioethics Center's decade of operation. The first section of the study will do the following: a) a Sankofan socio-ethical analysis of the Center's raison d'être; and b) definitions of ethical terms and the social world of the infamous syphilis study. The second section, as a result of the analysis, will address the Center's following challenges: c) the Center's challenge of theory and practice; d) the Center's challenge of moral heritage; and e) the Center's challenge of the future.

Space tug economic analysis study. Volume 2: Tug concepts analysis. Appendix: Tug design and performance data base

NASA Technical Reports Server (NTRS)

1972-01-01

The tug design and performance data base for the economic analysis of space tug operation are presented. A compendium of the detailed design and performance information from the data base is developed. The design data are parametric across a range of reusable space tug sizes. The performance curves are generated for selected point designs of expendable orbit injection stages and reusable tugs. Data are presented in the form of graphs for various modes of operation.

Robot and Human Surface Operations on Solar System Bodies

NASA Technical Reports Server (NTRS)

Weisbin, C. R.; Easter, R.; Rodriguez, G.

2001-01-01

This paper presents a comparison of robot and human surface operations on solar system bodies. The topics include: 1) Long Range Vision of Surface Scenarios; 2) Human and Robots Complement Each Other; 3) Respective Human and Robot Strengths; 4) Need More In-Depth Quantitative Analysis; 5) Projected Study Objectives; 6) Analysis Process Summary; 7) Mission Scenarios Decompose into Primitive Tasks; 7) Features of the Projected Analysis Approach; and 8) The "Getting There Effect" is a Major Consideration. This paper is in viewgraph form.

Wavelet and receiver operating characteristic analysis of heart rate variability

NASA Astrophysics Data System (ADS)

McCaffery, G.; Griffith, T. M.; Naka, K.; Frennaux, M. P.; Matthai, C. C.

2002-02-01

Multiresolution wavelet analysis has been used to study the heart rate variability in two classes of patients with different pathological conditions. The scale dependent measure of Thurner et al. was found to be statistically significant in discriminating patients suffering from hypercardiomyopathy from a control set of normal subjects. We have performed Receiver Operating Characteristc (ROC) analysis and found the ROC area to be a useful measure by which to label the significance of the discrimination, as well as to describe the severity of heart dysfunction.

Geostationary platform systems concepts definition study. Volume 2: Technical, book 1

NASA Technical Reports Server (NTRS)

1980-01-01

The initial selection and definition of operational geostationary platform concepts is discussed. Candidate geostationary platform missions and payloads were identified from COMSAT, Aerospace, and NASA studies. These missions and payloads were cataloged; classified with to communications, military, or scientific uses; screened for application and compatibility with geostationary platforms; and analyzed to identify platform requirements. Two platform locations were then selected (Western Hemisphere - 110 deg W, and Atlantic - 15 deg W), and payloads allocated based on nominal and high traffic models. Trade studies were performed leading to recommendation of selected concepts. Of 30 Orbit Transfer Vehicle (0TV) configuration and operating mode options identified, 18 viable candidates compatible with the operational geostationary platform missions were selected for analysis. Each was considered using four platform operational modes - 8 or 16 year life, and serviced or nonserviced, providing a total of 72 OTV/platform-mode options. For final trade study concept selection, a cost program was developed considering payload and platform costs and weight; transportation unit and total costs for the shuttle and OTV; and operational costs such as assembly or construction time, mating time, and loiter time. Servicing costs were added for final analysis and recommended selection.

Analysis of operational requirements for medium density air transportation, volume 2

NASA Technical Reports Server (NTRS)

1975-01-01

The medium density air travel market is examined and defined in terms of numbers of people transported per route per day and frequency of service. The operational characteristics for aircraft to serve this market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations can be conducted. The impact of the operational characteristics on the air travel system is evaluated along with the economic viability of the study aircraft. Research and technology programs for future study consideration are identified.

PRELIMINARY FACTOR ANALYSIS OF VISUAL COGNITION AND MEMORY. STUDIES IN CINE-PSYCHOMETRY, FINAL REPORT, PART I.

ERIC Educational Resources Information Center

SEIBERT, WARREN F.; AND OTHERS

PRELIMINARY ANALYSES WERE UNDERTAKEN TO DETERMINE THE POTENTIAL CONTRIBUTION OF MOTION PICTURE FILMS TO FACTOR ANALYTIC STUDIES OF HUMAN INTELLECT. OF PRIMARY CONCERN WERE THE OPERATIONS OF COGNITION AND MEMORY, FORMING TWO OF THE FIVE OPERATION COLUMNS OF GUILFORD'S "STRUCTURE OF INTELLECT." THE CORE REFERENCE FOR THE STUDY WAS DEFINED…

Operant Conditioning Concepts in Introductory Psychology Textbooks and Their Companion Web Sites

ERIC Educational Resources Information Center

Sheldon, Jane P.

2002-01-01

Psychology instructors and textbook authors rate operant conditioning as one of the most essential concepts for students to learn, yet textbook writers, as well as students, can fall prey to misconceptions. This study is a content analysis of the presentation of operant conditioning in introductory psychology textbooks and their companion Web…

Jackknife variance of the partial area under the empirical receiver operating characteristic curve.

PubMed

Bandos, Andriy I; Guo, Ben; Gur, David

2017-04-01

Receiver operating characteristic analysis provides an important methodology for assessing traditional (e.g., imaging technologies and clinical practices) and new (e.g., genomic studies, biomarker development) diagnostic problems. The area under the clinically/practically relevant part of the receiver operating characteristic curve (partial area or partial area under the receiver operating characteristic curve) is an important performance index summarizing diagnostic accuracy at multiple operating points (decision thresholds) that are relevant to actual clinical practice. A robust estimate of the partial area under the receiver operating characteristic curve is provided by the area under the corresponding part of the empirical receiver operating characteristic curve. We derive a closed-form expression for the jackknife variance of the partial area under the empirical receiver operating characteristic curve. Using the derived analytical expression, we investigate the differences between the jackknife variance and a conventional variance estimator. The relative properties in finite samples are demonstrated in a simulation study. The developed formula enables an easy way to estimate the variance of the empirical partial area under the receiver operating characteristic curve, thereby substantially reducing the computation burden, and provides important insight into the structure of the variability. We demonstrate that when compared with the conventional approach, the jackknife variance has substantially smaller bias, and leads to a more appropriate type I error rate of the Wald-type test. The use of the jackknife variance is illustrated in the analysis of a data set from a diagnostic imaging study.

Analysis and Evaluation of 137 ESEA Title III Planning and Operational Grants. Report No. 4 of the Second National Study of PACE.

ERIC Educational Resources Information Center

Fairfax County Schools, Baileys Crossroads, VA. Center for Effecting Educational Change.

This report is an assessment of the overall impact and influence on education of 137 terminated Planning and Operational Grants made under the ESEA Title III Projects to Advance Creativity in Education (PACE) program. Analysis and evaluation seek to determine whether (1) individual project objectives were identified and achieved, (2) PACE…

Screening for Depressive Disorders Using the Mood and Anxiety Symptoms Questionnaire Anhedonic Depression Scale: A Receiver-Operating Characteristic Analysis

ERIC Educational Resources Information Center

Bredemeier, Keith; Spielberg, Jeffery M.; Silton, Rebecca Levin; Berenbaum, Howard; Heller, Wendy; Miller, Gregory A.

2010-01-01

The present study examined the utility of the anhedonic depression scale from the Mood and Anxiety Symptoms Questionnaire (MASQ-AD scale) as a way to screen for depressive disorders. Using receiver-operating characteristic analysis, we examined the sensitivity and specificity of the full 22-item MASQ-AD scale, as well as the 8- and 14-item…

NASA TLA workload analysis support. Volume 1: Detailed task scenarios for general aviation and metering and spacing studies

NASA Technical Reports Server (NTRS)

Sundstrom, J. L.

1980-01-01

The techniques required to produce and validate six detailed task timeline scenarios for crew workload studies are described. Specific emphasis is given to: general aviation single pilot instrument flight rules operations in a high density traffic area; fixed path metering and spacing operations; and comparative workload operation between the forward and aft-flight decks of the NASA terminal control vehicle. The validation efforts also provide a cursory examination of the resultant demand workload based on the operating procedures depicted in the detailed task scenarios.

Experimental study of combustion processes involved in hypergolic propellant coaxial injector operation

NASA Astrophysics Data System (ADS)

Habiballah, M.; Dubois, I.; Gicquel, P.; Foucaud, R.

1992-07-01

The first results are presented of an experimental research program to understand the operation of a coaxial injector using hypergolic propellants. Mechanisms and processes involved in coaxial injector operation are identified for a two-plate injector and a coaxial injector. The usefulness of backlight cinematography and laser sheet visualization in the study of coaxial injector operation is examined. A review of the literature on injector elements using highly reactive hypergolic propellants is presented along with an analysis of fundamental mechanisms involved in these propellants.

The Nez Perce Flight to Canada: An Analysis of the Nez Perce-US Cavalry Conflicts: Applying Historical Lessons Learned to Modern Counterinsurgency and Global War on Terrorism Operations

DTIC Science & Technology

2006-06-16

COUNTERINSURGENCY AND GLOBAL WAR ON TERRORISM OPERATIONS A thesis presented to the Faculty of the US Army Command and General Staff College in partial... Terrorism and counterinsurgency operations in Iraq and Afghanistan. The US Cavalry’s clash with the Nez Perce provides an excellent case study. Their...LESSONS LEARNED TO MODERN COUNTERINSURGENCY AND GLOBAL WAR ON TERRORISM OPERATIONS, by MAJ Scott E. Pfau, 81 pages. This study details the Nez

Flight Technical Error Analysis of the SATS Higher Volume Operations Simulation and Flight Experiments

NASA Technical Reports Server (NTRS)

Williams, Daniel M.; Consiglio, Maria C.; Murdoch, Jennifer L.; Adams, Catherine H.

2005-01-01

This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.

Wind study for high altitude platform design

NASA Technical Reports Server (NTRS)

Strganac, T. W.

1979-01-01

An analysis of upper air winds was performed to define the wind environment at potential operating altitudes for high-altitude powered platform concepts. Expected wind conditions of the contiguous United States, Pacific area (Alaska to Sea of Japan), and European area (Norwegian and Mediterranean Seas) were obtained using a representative network of sites selected based upon adequate high-altitude sampling, geographic dispersion, and observed upper wind patterns. A data base of twenty plus years of rawinsonde gathered wind information was used in the analysis. Annual variations from surface to 10 mb (approximately 31 km) pressure altitude were investigated to encompass the practical operating range for the platform concepts. Parametric analysis for the United States and foreign areas was performed to provide a basis for vehicle system design tradeoffs. This analysis of wind magnitudes indicates the feasibility of annual operation at a majority of sites and more selective seasonal operation for the extreme conditions between the pressure altitudes of 100 to 25 mb based upon the assumed design speeds.

Wind study for high altitude platform design

NASA Technical Reports Server (NTRS)

Strganac, T. W.

1979-01-01

An analysis of upper air winds was performed to define the wind environment at potential operating altitudes for high altitude powered platform concepts. Wind conditions of the continental United States, Pacific area (Alaska to Sea of Japan), and European area (Norwegian and Mediterranean Sea) were obtained using a representative network of sites selected based upon adequate high altitude sampling, geographic dispersion, and observed upper wind patterns. A data base of twenty plus years of rawinsonde gathered wind information was used in the analysis. Annual variations from surface to 10 mb pressure altitude were investigated to encompass the practical operating range for the platform concepts. Parametric analysis for the United States and foreign areas was performed to provide a basis for vehicle system design tradeoffs. This analysis of wind magnitudes indicates the feasibility of annual operation at a majority of sites and more selective seasonal operation for the extreme conditions between the pressure altitudes of 100 to 25 mb based upon the assumed design speeds.

NHEXAS PHASE I MARYLAND STUDY--LIST OF AVAILABLE DOCUMENTS: PROTOCOLS AND SOPS

EPA Science Inventory

This document lists available protocols and SOPs for the NHEXAS Phase I Maryland study. It identifies protocols and SOPs for the following study components: (1) Sample collection and field operations, (2) Sample analysis and general laboratory procedures, (3) Data Analysis Proced...

An activity-based methodology for operations cost analysis

NASA Technical Reports Server (NTRS)

Korsmeyer, David; Bilby, Curt; Frizzell, R. A.

1991-01-01

This report describes an activity-based cost estimation method, proposed for the Space Exploration Initiative (SEI), as an alternative to NASA's traditional mass-based cost estimation method. A case study demonstrates how the activity-based cost estimation technique can be used to identify the operations that have a significant impact on costs over the life cycle of the SEI. The case study yielded an operations cost of $101 billion for the 20-year span of the lunar surface operations for the Option 5a program architecture. In addition, the results indicated that the support and training costs for the missions were the greatest contributors to the annual cost estimates. A cost-sensitivity analysis of the cultural and architectural drivers determined that the length of training and the amount of support associated with the ground support personnel for mission activities are the most significant cost contributors.

Instability risk analysis and risk assessment system establishment of underground storage caverns in bedded salt rock

NASA Astrophysics Data System (ADS)

Jing, Wenjun; Zhao, Yan

2018-02-01

Stability is an important part of geotechnical engineering research. The operating experiences of underground storage caverns in salt rock all around the world show that the stability of the caverns is the key problem of safe operation. Currently, the combination of theoretical analysis and numerical simulation are the mainly adopts method of reserve stability analysis. This paper introduces the concept of risk into the stability analysis of underground geotechnical structure, and studies the instability of underground storage cavern in salt rock from the perspective of risk analysis. Firstly, the definition and classification of cavern instability risk is proposed, and the damage mechanism is analyzed from the mechanical angle. Then the main stability evaluating indicators of cavern instability risk are proposed, and an evaluation method of cavern instability risk is put forward. Finally, the established cavern instability risk assessment system is applied to the analysis and prediction of cavern instability risk after 30 years of operation in a proposed storage cavern group in the Huai’an salt mine. This research can provide a useful theoretical base for the safe operation and management of underground storage caverns in salt rock.

Field Artillery And Fire Support At The Operational Level: An Analysis Of Operation Desert Storm and Operation Iraqi Freedom

DTIC Science & Technology

2017-05-25

Field Artillery and Fire Support at the Operational Level: An Analysis of Operation Desert Storm and Operation Iraqi Freedom A Monograph...Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204...AND SUBTITLE Field Artillery and Fire Support at the Operational Level: An Analysis of Operation Desert Storm and Operation Iraqi Freedom 5a

A qualitative content analysis of global health engagements in Peacekeeping and Stability Operations Institute's stability operations lessons learned and information management system.

PubMed

Nang, Roberto N; Monahan, Felicia; Diehl, Glendon B; French, Daniel

2015-04-01

Many institutions collect reports in databases to make important lessons-learned available to their members. The Uniformed Services University of the Health Sciences collaborated with the Peacekeeping and Stability Operations Institute to conduct a descriptive and qualitative analysis of global health engagements (GHEs) contained in the Stability Operations Lessons Learned and Information Management System (SOLLIMS). This study used a summative qualitative content analysis approach involving six steps: (1) a comprehensive search; (2) two-stage reading and screening process to identify first-hand, health-related records; (3) qualitative and quantitative data analysis using MAXQDA, a software program; (4) a word cloud to illustrate word frequencies and interrelationships; (5) coding of individual themes and validation of the coding scheme; and (6) identification of relationships in the data and overarching lessons-learned. The individual codes with the most number of text segments coded included: planning, personnel, interorganizational coordination, communication/information sharing, and resources/supplies. When compared to the Department of Defense's (DoD's) evolving GHE principles and capabilities, the SOLLIMS coding scheme appeared to align well with the list of GHE capabilities developed by the Department of Defense Global Health Working Group. The results of this study will inform practitioners of global health and encourage additional qualitative analysis of other lessons-learned databases. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Methods of Collection of Biological Information for Fatigue Evaluation during Visual Display Terminals (VDT) Operation

NASA Astrophysics Data System (ADS)

Hachiya, Yuriko; Ogai, Harutoshi; Okazaki, Hiroko; Fujisaki, Takeshi; Uchida, Kazuhiko; Oda, Susumu; Wada, Futoshi; Mori, Koji

A method for the analysis of fatigue parameters has been rarely researched in VDT operation. Up to now, fatigue was evaluated by changing of biological information. If signals regarding fatigue are detected, fatigue can be measured. The purpose of this study proposed experiment and analysis method to extract parameters related to fatigue from the biological information during VDT operation using the Independent Component Analysis (ICA). An experiment had 11 subjects. As for the experiment were light loaded VDT operation and heavy loaded VDT operation. A measurement item were amount of work, a mistake number, subjective symptom, surface skin temperature (forehead and apex nasi), heart rate, skin blood flow of forearm and respiratory rate. In the heavy loaded operation group, mistake number and subjective symptom score were increased to compare with the other. And Two-factor ANOVA was used for analysis. The result of mistake number was confirmed that heavy loaded. After the moving averages of waveshape were calculated, it was made to extract independent components by using the ICA. The results of the ICA suggest that the independent components increase according to accumulation of fatigue. Thus, the independent components would be a possible parameter of fatigue. However, further experiments should continue in order to obtain the conclusive finding of our research.

Life Cycle Energy Assessment of a Multi-storey Residential Building

NASA Astrophysics Data System (ADS)

Mehta, Sourabh; Chandur, Arjun; Palaniappan, Sivakumar

2017-06-01

This study presents the findings of life cycle energy assessment of two multi-storey residential buildings. These buildings consist of a total of 60 homes. The usable floor area is 43.14 m2 (463.36 ft2) per home. A detailed estimation of embodied energy is carried out by considering the use of materials during building construction. Major contributors of embodied energy are found to be steel, cement and aluminum. Monthly building operation energy was assessed using a total of 2520 data samples corresponding to 3 years of building operation. Analysis of a base case scenario, with 50 years of service life and average monthly operation energy, indicates that the embodied energy and the operation energy account for 16 and 84% of the life cycle energy respectively. Sensitivity analysis is carried out to study the influence of service life and operation energy on the relative contribution of embodied energy and operation energy. It is found that the embodied energy represents as high as 31% of the life cycle energy depending upon the variation in the operation energy and the service life. Hence, strategies towards sustainable building construction should also focus on reducing the embodied energy in the design and construction phases in addition to operation energy.

Operative reports: form and function.

PubMed

Stewart, Lygia; Hunter, John G; Wetter, Alberto; Chin, Brian; Way, Lawrence W

2010-09-01

Little is known about how closely operative reports reflect what was actually performed during an operation, nor has the construction of operative reports been adequately studied with the aims of clarifying the objectives of those reports and improving their efficacy. We hypothesized that if more attention is paid to the objectives of operative reports, their content will more predictably contain the most relevant information, which might channel thinking in beneficial directions during performance of the operation. Multivariate analysis of 250 laparoscopic cholecystectomy operative reports (125 uncomplicated and 125 with bile duct injury). Academic research. University (105 cases) and community (145 cases) hospitals. Variations in content and design of operative reports. Cognitive task analysis of laparoscopic cholecystectomy was conducted, and a model operative report was generated and compared with the actual operative reports. Descriptions of key elements in adequate dissection of the Calot triangle were present in 24.8% and 0.0% of operative reports from uncomplicated and bile duct injury cases, respectively. Thorough dissection of the Calot triangle, identification of the cystic duct-infundibulum junction, and lateral retraction of the infundibulum correlated with uncomplicated cases, while irregular cues (eg, perceived anatomic or other deviations) correlated with bile duct injury cases. Current practice generates operative reports that vary widely in content and too often omit important elements. This research suggests that the construction of operative reports should be constrained such that the reports routinely include the fundamental goals of the operation and what was performed to meet them. Cognitive task analysis is based on the ways the mind controls the performance of tasks; it is an excellent method for determining the extra content needed in operative reports. The resulting designs should also serve as mental guidelines to facilitate learning and to enhance the safety of the operation.

Ex post power economic analysis of record of decision operational restrictions at Glen Canyon Dam.

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

Veselka, T. D.; Poch, L. A.; Palmer, C. S.

On October 9, 1996, Bruce Babbitt, then-Secretary of the U.S. Department of the Interior signed the Record of Decision (ROD) on operating criteria for the Glen Canyon Dam (GCD). Criteria selected were based on the Modified Low Fluctuating Flow (MLFF) Alternative as described in the Operation of Glen Canyon Dam, Colorado River Storage Project, Arizona, Final Environmental Impact Statement (EIS) (Reclamation 1995). These restrictions reduced the operating flexibility of the hydroelectric power plant and therefore its economic value. The EIS provided impact information to support the ROD, including an analysis of operating criteria alternatives on power system economics. This exmore » post study reevaluates ROD power economic impacts and compares these results to the economic analysis performed prior (ex ante) to the ROD for the MLFF Alternative. On the basis of the methodology used in the ex ante analysis, anticipated annual economic impacts of the ROD were estimated to range from approximately $15.1 million to $44.2 million in terms of 1991 dollars ($1991). This ex post analysis incorporates historical events that took place between 1997 and 2005, including the evolution of power markets in the Western Electricity Coordinating Council as reflected in market prices for capacity and energy. Prompted by ROD operational restrictions, this analysis also incorporates a decision made by the Western Area Power Administration to modify commitments that it made to its customers. Simulated operations of GCD were based on the premise that hourly production patterns would maximize the economic value of the hydropower resource. On the basis of this assumption, it was estimated that economic impacts were on average $26.3 million in $1991, or $39 million in $2009.« less

Studying the Cognitive Emphases of Teachers' Classroom Questions.

ERIC Educational Resources Information Center

Davis, O. L., Jr.; And Others

1969-01-01

Recent interest in the direct, descriptive study of teaching has led to renewed attention to the types of questions asked by teachers. An important contributing factor has also been the progress made in the analysis of cognitive operations and the identification of a complex hierarchy of operations. Several observation systems developed from…

Problem-Based Learning for Production and Operations Management

ERIC Educational Resources Information Center

Kanet, John J.; Barut, Mehmet

2003-01-01

In this paper, we describe our application of "problem-based learning" in the teaching of production/operations management. We describe a study of the effectiveness of this approach and present the results and analysis of this study. We provide a collection of our experiences in using this method and conclude with some general…

Spacelab user implementation assessment study (software requirements analysis). Volume 1: Executive study

NASA Technical Reports Server (NTRS)

1976-01-01

The primary objective of this study was to develop an integrated approach for the development, implementation, and utilization of all software that is required to efficiently and cost-effectively support advanced technology laboratory flight and ground operations. It was recognized that certain aspects of the operations would be mandatory computerized services; computerization of other aspects would be optional. Thus, the analyses encompassed not only alternate computer utilization and implementations but trade studies of the programmatic effects of non-computerized versus computerized approaches to the operations. A general overview of the study is presented.

Performance analysis of radiation cooled dc transmission lines for high power space systems

NASA Technical Reports Server (NTRS)

Schwarze, G. E.

1985-01-01

As space power levels increase to meet mission objectives and also as the transmission distance between power source and load increases, the mass, volume, power loss, and operating voltage and temperature become important system design considerations. This analysis develops the dependence of the specific mass and percent power loss on hte power and voltage levels, transmission distance, operating temperature and conductor material properties. Only radiation cooling is considered since the transmission line is assumed to operate in a space environment. The results show that the limiting conditions for achieving low specific mass, percent power loss, and volume for a space-type dc transmission line are the permissible transmission voltage and operating temperature. Other means to achieve low specific mass include the judicious choice of conductor materials. The results of this analysis should be immediately applicable to power system trade-off studies including comparisons with ac transmission systems.

Analysis of the U.S. geological survey streamgaging network

USGS Publications Warehouse

Scott, A.G.

1987-01-01

This paper summarizes the results from the first 3 years of a 5-year cost-effectiveness study of the U.S. Geological Survey streamgaging network. The objective of the study is to define and document the most cost-effective means of furnishing streamflow information. In the first step of this study, data uses were identified for 3,493 continuous-record stations currently being operated in 32 States. In the second step, evaluation of alternative methods of providing streamflow information, flow-routing models, and regression models were developed for estimating daily flows at 251 stations of the 3,493 stations analyzed. In the third step of the analysis, relationships were developed between the accuracy of the streamflow records and the operating budget. The weighted standard error for all stations, with current operating procedures, was 19.9 percent. By altering field activities, as determined by the analyses, this could be reduced to 17.8 percent. The existing streamgaging networks in four Districts were further analyzed to determine the impacts that satellite telemetry would have on the cost effectiveness. Satellite telemetry was not found to be cost effective on the basis of hydrologic data collection alone, given present cost of equipment and operation.This paper summarizes the results from the first 3 years of a 5-year cost-effectiveness study of the U. S. Geological Survey streamgaging network. The objective of the study is to define and document the most cost-effective means of furnishing streamflow information. In the first step of this study, data uses were identified for 3,493 continuous-record stations currently being operated in 32 States. In the second step, evaluation of alternative methods of providing streamflow information, flow-routing models, and regression models were developed for estimating daily flows at 251 stations of the 3, 493 stations analyzed. In the third step of the analysis, relationships were developed between the accuracy of the streamflow records and the operating budget. The weighted standard error for all stations, with current operating procedures, was 19. 9 percent. By altering field activities, as determined by the analyses, this could be reduced to 17. 8 percent. Additional study results are discussed.

Analysis of Risk Factors for Postoperative Morbidity in Perforated Peptic Ulcer

PubMed Central

Kim, Jae-Myung; Jeong, Sang-Ho; Park, Soon-Tae; Choi, Sang-Kyung; Hong, Soon-Chan; Jung, Eun-Jung; Ju, Young-Tae; Jeong, Chi-Young; Ha, Woo-Song

2012-01-01

Purpose Emergency operations for perforated peptic ulcer are associated with a high incidence of postoperative complications. While several studies have investigated the impact of perioperative risk factors and underlying diseases on the postoperative morbidity after abdominal surgery, only a few have analyzed their role in perforated peptic ulcer disease. The purpose of this study was to determine any possible associations between postoperative morbidity and comorbid disease or perioperative risk factors in perforated peptic ulcer. Materials and Methods In total, 142 consecutive patients, who underwent surgery for perforated peptic ulcer, at a single institution, between January 2005 and October 2010 were included in this study. The clinical data concerning the patient characteristics, operative methods, and complications were collected retrospectively. Results The postoperative morbidity rate associated with perforated peptic ulcer operations was 36.6% (52/142). Univariate analysis revealed that a long operating time, the open surgical method, age (≥60), sex (female), high American Society of Anesthesiologists (ASA) score and presence of preoperative shock were significant perioperative risk factors for postoperative morbidity. Significant comorbid risk factors included hypertension, diabetes mellitus and pulmonary disease. Multivariate analysis revealed a long operating time, the open surgical method, high ASA score and the presence of preoperative shock were all independent risk factors for the postoperative morbidity in perforated peptic ulcer. Conclusions A high ASA score, preoperative shock, open surgery and long operating time of more than 150 minutes are high risk factors for morbidity. However, there is no association between postoperative morbidity and comorbid disease in patients with a perforated peptic ulcer. PMID:22500261

A Validated Task Analysis of the Single Pilot Operations Concept

NASA Technical Reports Server (NTRS)

Wolter, Cynthia A.; Gore, Brian F.

2015-01-01

The current day flight deck operational environment consists of a two-person Captain/First Officer crew. A concept of operations (ConOps) to reduce the commercial cockpit to a single pilot from the current two pilot crew is termed Single Pilot Operations (SPO). This concept has been under study by researchers in the Flight Deck Display Research Laboratory (FDDRL) at the National Aeronautics and Space Administration's (NASA) Ames (Johnson, Comerford, Lachter, Battiste, Feary, and Mogford, 2012) and researchers from Langley Research Centers (Schutte et al., 2007). Transitioning from a two pilot crew to a single pilot crew will undoubtedly require changes in operational procedures, crew coordination, use of automation, and in how the roles and responsibilities of the flight deck and ATC are conceptualized in order to maintain the high levels of safety expected of the US National Airspace System. These modifications will affect the roles and the subsequent tasks that are required of the various operators in the NextGen environment. The current report outlines the process taken to identify and document the tasks required by the crew according to a number of operational scenarios studied by the FDDRL between the years 2012-2014. A baseline task decomposition has been refined to represent the tasks consistent with a new set of entities, tasks, roles, and responsibilities being explored by the FDDRL as the move is made towards SPO. Information from Subject Matter Expert interviews, participation in FDDRL experimental design meetings, and study observation was used to populate and refine task sets that were developed as part of the SPO task analyses. The task analysis is based upon the proposed ConOps for the third FDDRL SPO study. This experiment possessed nine different entities operating in six scenarios using a variety of SPO-related automation and procedural activities required to guide safe and efficient aircraft operations. The task analysis presents the roles and responsibilities in a manner that can facilitate testing future scenarios. Measures of task count and workload were defined and analyzed to assess the impact of transitioning to a SPO environment.

Space tug economic analysis study. Volume 2: Tug concepts analysis. Part 2: Economic analysis

NASA Technical Reports Server (NTRS)

1972-01-01

An economic analysis of space tug operations is presented. The subjects discussed are: (1) cost uncertainties, (2) scenario analysis, (3) economic sensitivities, (4) mixed integer programming formulation of the space tug problem, and (5) critical parameters in the evaluation of a public expenditure.

Satellite services system analysis study. Volume 5: Programmatics

NASA Technical Reports Server (NTRS)

1981-01-01

The overall program and resources needed for development and operation of a Satellite Services System is reviewed. Program requirements covered system operations through 1993 and were completed in preliminary form. Program requirements were refined based on equipment preliminary design and analysis. Schedules, costs, equipment utilization, and facility/advanced technology requirements were included in the update. Equipment user charges were developed for each piece of equipment and for representative satellite servicing missions.

Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Volume 5: Analysis of core damage frequency from seismic events for plant operational state 5 during a refueling outage

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

Budnitz, R.J.; Davis, P.R.; Ravindra, M.K.

In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Sandia National Laboratories studying a boiling water reactor (Grand Gulf), and the other at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1). Both the Sandia and Brookhaven projects have examined only accidents initiated by internal plant faults---so-called ``internal initiators.`` This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling outage conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. Thismore » report covers the seismic analysis at Grand Gulf. All of the many systems modeling assumptions, component non-seismic failure rates, and human effort rates that were used in the internal-initiator study at Grand Gulf have been adopted here, so that the results of the study can be as comparable as possible. Both the Sandia study and this study examine only one shutdown plant operating state (POS) at Grand Gulf, namely POS 5 representing cold shutdown during a refueling outage. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POS 5. The results of the analysis are that the core-damage frequency for earthquake-initiated accidents during refueling outages in POS 5 is found to be quite low in absolute terms, less than 10{sup {minus}7}/year.« less

Thermal and Evolved Gas Analysis of Calcite Under Reduced Operating Pressures: Implications for the 2011 MSL Sample Analysis at Mars (SAM) Instrument

NASA Technical Reports Server (NTRS)

Lauer, H. V. Jr.; Ming, D. W.; Sutter, B.; Mahaffy, P. R.

2010-01-01

The Mars Science Laboratory (MSL) is scheduled for launch in 2011. The science objectives for MSL are to assess the past or present biological potential, to characterize the geology, and to investigate other planetary processes that influence habitability at the landing site. The Sample Analysis at Mars (SAM) is a key instrument on the MSL payload that will explore the potential habitability at the landing site [1]. In addition to searching for organic compounds, SAM will have the capability to characterized evolved gases as a function of increasing temperature and provide information on the mineralogy of volatile-bearing phases such as carbonates, sulfates, phyllosilicates, and Fe-oxyhydroxides. The operating conditions in SAM ovens will be maintained at 30 mb pressure with a He carrier gas flowing at 1 sccm. We have previously characterized the thermal and evolved gas behaviors of volatile-bearing species under reduced pressure conditions that simulated operating conditions of the Thermal and Evolved Gas Analyzer (TEGA) that was onboard the 2007 Mars Phoenix Scout Mission [e.g., 2-8]. TEGA ovens operated at 12 mb pressure with a N2 carrier gas flowing at 0.04 sccm. Another key difference between SAM and TEGA is that TEGA was able to perform differential scanning calorimetry whereas SAM only has a pyrolysis oven. The operating conditions for TEGA and SAM have several key parameter differences including operating pressure (12 vs 30 mb), carrier gas (N2 vs. He), and carrier gas flow rate (0.04 vs 1 sccm). The objectives of this study are to characterize the thermal and evolved gas analysis of calcite under SAM operating conditions and then compare it to calcite thermal and evolved gas analysis under TEGA operating conditions.

Comparison of mosquito control programs in seven urban sites in Africa, the Middle East, and the Americas.

PubMed

Impoinvil, Daniel E; Ahmad, Sajjad; Troyo, Adriana; Keating, Joseph; Githeko, Andrew K; Mbogo, Charles M; Kibe, Lydiah; Githure, John I; Gad, Adel M; Hassan, Ali N; Orshan, Laor; Warburg, Alon; Calderón-Arguedas, Olger; Sánchez-Loría, Victoria M; Velit-Suarez, Rosanna; Chadee, Dave D; Novak, Robert J; Beier, John C

2007-10-01

Mosquito control programs at seven urban sites in Kenya, Egypt, Israel, Costa Rica, and Trinidad are described and compared. Site-specific urban and disease characteristics, organizational diagrams, and strengths, weaknesses, obstacles and threats (SWOT) analysis tools are used to provide a descriptive assessment of each mosquito control program, and provide a comparison of the factors affecting mosquito abatement. The information for SWOT analysis is collected from surveys, focus-group discussions, and personal communication. SWOT analysis identified various issues affecting the efficiency and sustainability of mosquito control operations. The main outcome of our work was the description and comparison of mosquito control operations within the context of each study site's biological, social, political, management, and economic conditions. The issues identified in this study ranged from lack of inter-sector collaboration to operational issues of mosquito control efforts. A lack of sustainable funding for mosquito control was a common problem for most sites. Many unique problems were also identified, which included lack of mosquito surveillance, lack of law enforcement, and negative consequences of human behavior. Identifying common virtues and shortcomings of mosquito control operations is useful in identifying "best practices" for mosquito control operations, thus leading to better control of mosquito biting and mosquito-borne disease transmission.

Comparison of mosquito control programs in seven urban sites in Africa, the Middle East, and the Americas

PubMed Central

Impoinvil, Daniel E.; Ahmad, Sajjad; Troyo, Adriana; Keating, Joseph; Githeko, Andrew K.; Mbogo, Charles M; Kibe, Lydiah; Githure, John I.; Gad, Adel M.; Hassan, Ali N.; Orshan, Laor; Warburg, Alon; Calderón-Arguedas, Olger; Sánchez-Loría, Victoria M.; Velit-Suarez, Rosanna; Chadee, Dave D.; Novak, Robert J.; Beier, John C.

2007-01-01

Mosquito control programs at seven urban sites in Kenya, Egypt, Israel, Costa Rica, and Trinidad are described and compared. Site-specific urban and disease characteristics, organizational diagrams, and strengths, weaknesses, obstacles and threats (SWOT) analysis tools are used to provide a descriptive assessment of each mosquito control program, and provide a comparison of the factors affecting mosquito abatement. The information for SWOT analysis is collected from surveys, focus group discussions, and personal communication. SWOT analysis identified various issues affecting the efficiency and sustainability of mosquito control operations. The main outcome of our work was the description and comparison of mosquito control operations within the context of each study site’s biological, social, political, management, and economic conditions. The issues identified in this study ranged from lack of inter-sector collaboration to operational issues of mosquito control efforts. A lack of sustainable funding for mosquito control was a common problem for most sites. Many unique problems were also identified, which included lack of mosquito surveillance, lack of law enforcement, and negative consequences of human behavior. Identifying common virtues and shortcomings of mosquito control operations is useful in identifying “best practices” for mosquito control operations, thus leading to better control of mosquito biting and mosquito-borne disease transmission. PMID:17316882

Stability assessment and operating parameter optimization on experimental results in very small plasma focus, using sensitivity analysis

NASA Astrophysics Data System (ADS)

Jafari, Hossein; Habibi, Morteza

2018-04-01

Regarding the importance of stability in small-scale plasma focus devices for producing the repeatable and strength pinching, a sensitivity analysis approach has been used for applicability in design parameters optimization of an actually very low energy device (84 nF, 48 nH, 8-9.5 kV, ∼2.7-3.7 J). To optimize the devices functional specification, four different coaxial electrode configurations have been studied, scanning an argon gas pressure range from 0.6 to 1.5 mbar via the charging voltage variation study from 8.3 to 9.3 kV. The strength and efficient pinching was observed for the tapered anode configuration, over an expanded operating pressure range of 0.6 to 1.5 mbar. The analysis results showed that the most sensitive of the pinch voltage was associated with 0.88 ± 0.8mbar argon gas pressure and 8.3-8.5 kV charging voltage, respectively, as the optimum operating parameters. From the viewpoint of stability assessment of the device, it was observed that the least variation in stable operation of the device was for a charging voltage range of 8.3 to 8.7 kV in an operating pressure range from 0.6 to 1.1 mbar.

Primary anastomosis or ostomy in necrotizing enterocolitis?

PubMed

Haricharan, Ramanathapura N; Gallimore, Jade Palazzola; Nasr, Ahmed

2017-11-01

In neonates requiring operation for necrotizing enterocolitis (NEC), the complications due to enterostomy (ES) and the need for another operation to restore continuity have prompted several surgeons to employ primary anastomosis (PA) after resection as the operative strategy of choice. Our objective was to compare primary anastomosis to stoma formation in this population using systematic review and meta-analysis. Publications describing both interventions were identified by searching multiple databases. Appropriate studies that reported outcomes after PA and ES for NEC were included for analysis that was performed using the MedCalc3000 software. Results are reported as odds ratios (OR, 95% CI). No randomized trials were identified. Twelve studies were included for the final analysis. Neonates who underwent PA were associated with significantly less risk of mortality when compared to those who underwent ES (OR 0.34, 95% CI 0.17-0.68, p 0.002), possibly due to differences in severity of NEC. Although the types of complications in these groups were different, there was no significant difference in risk of complication (OR 0.86, 0.55-1.33, p 0.50). In neonates undergoing an operation for severe NEC, there is no significant difference in the risk of complications between primary anastomosis and enterostomy. A definitive suggestion cannot be made regarding the choice of one operative strategy over another.

Performance Evaluation of Counter-Based Dynamic Load Balancing Schemes for Massive Contingency Analysis with Different Computing Environments

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

Chen, Yousu; Huang, Zhenyu; Chavarría-Miranda, Daniel

Contingency analysis is a key function in the Energy Management System (EMS) to assess the impact of various combinations of power system component failures based on state estimation. Contingency analysis is also extensively used in power market operation for feasibility test of market solutions. High performance computing holds the promise of faster analysis of more contingency cases for the purpose of safe and reliable operation of today’s power grids with less operating margin and more intermittent renewable energy sources. This paper evaluates the performance of counter-based dynamic load balancing schemes for massive contingency analysis under different computing environments. Insights frommore » the performance evaluation can be used as guidance for users to select suitable schemes in the application of massive contingency analysis. Case studies, as well as MATLAB simulations, of massive contingency cases using the Western Electricity Coordinating Council power grid model are presented to illustrate the application of high performance computing with counter-based dynamic load balancing schemes.« less

Implementation and evaluation of an interprofessional simulation-based education program for undergraduate nursing students in operating room nursing education: a randomized controlled trial.

PubMed

Wang, Rongmei; Shi, Nianke; Bai, Jinbing; Zheng, Yaguang; Zhao, Yue

2015-07-09

The present study was designed to implement an interprofessional simulation-based education program for nursing students and evaluate the influence of this program on nursing students' attitudes toward interprofessional education and knowledge about operating room nursing. Nursing students were randomly assigned to either the interprofessional simulation-based education or traditional course group. A before-and-after study of nursing students' attitudes toward the program was conducted using the Readiness for Interprofessional Learning Scale. Responses to an open-ended question were categorized using thematic content analysis. Nursing students' knowledge about operating room nursing was measured. Nursing students from the interprofessional simulation-based education group showed statistically different responses to four of the nineteen questions in the Readiness for Interprofessional Learning Scale, reflecting a more positive attitude toward interprofessional learning. This was also supported by thematic content analysis of the open-ended responses. Furthermore, nursing students in the simulation-based education group had a significant improvement in knowledge about operating room nursing. The integrated course with interprofessional education and simulation provided a positive impact on undergraduate nursing students' perceptions toward interprofessional learning and knowledge about operating room nursing. Our study demonstrated that this course may be a valuable elective option for undergraduate nursing students in operating room nursing education.

Analysis of space tug operating techniques (study 2.4). Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1972-01-01

The costs of tug refurbishment were studied, using existing cost estimating relationships, to establish the cost of maintaining the reusable third stage of the space transportation system. Refurbishment operations sheets which describe the actual tasks that are necessary to keep the equipment functioning properly were used along with refurbishment operations sheets which contain all of the pertinent descriptive information for each of the major vehicle areas. Tug refurbishment costs per mission are tabulated.

Rapid Operational Access and Maneuver Support (ROAMS) Platform for Improved Military Logistics Lines of Communication and Operational Vessel Routing

DTIC Science & Technology

2017-06-01

case study in a northeastern American metropolitan area. METHODOLOGY : The ROAMS platform provides expanded analysis, model automation, and enhanced...shoals. An initial route for such operations is selected much like the military logistics case . Subsequent adjustments to routes may be done on an ad...IX-45 June 2017 8 CASE STUDY: The ROAMS platform was applied to a large, northeast American metropolitan region to demonstrate the capability of

Linking performance benchmarking of refinery process chemicals to refinery key performance indicators

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

Cook, J.M.; Nieman, L.D.

In 1977 Solomon Associates, Inc. issued its first study of refining in the US entitled, Comparative Performance Analysis for Fuel Product Refineries, most commonly referred to as the Solomon Study, or the Fuels Study. In late 1993, both the Water and Waste Water Management, and Petroleum Divisions of Nalco Chemical Company came to the same conclusion; that they must have a better understanding of the Solomon Study process, and have some input to this system of measurement. The authors first approached Solomon Associates with the idea that a specific study should be done of specialty chemicals used in the refinery.more » They felt that this would result in two studies, one for water treatment applications, and one for process. The water treatment study came first, and was completed in 1993 with the United States Petroleum Refineries Water Treatment Performance Analysis for Operating Year 1993. The process study, entitled United States Petroleum Refinery Process Treatment Performance Analysis for Operating Years 1994--95 will be issued in the 2nd quarter of this year by Nalco/Exxon Energy Chemicals, L.P, which includes the combined resources of the former Petroleum Division of Nalco Chemical Company (including the petroleum related portions of most of its overseas companies), and the petroleum related specialty chemical operations of Exxon Chemical on a global basis. What follows is a recap of the process study focus, some examples of output, and comment on both the linkage to key refinery operating indicators, as well as the perception of the effect of such measurement on the supplier relationship of the future.« less

Task-dependent signal variations in EEG error-related potentials for brain-computer interfaces.

PubMed

Iturrate, I; Montesano, L; Minguez, J

2013-04-01

A major difficulty of brain-computer interface (BCI) technology is dealing with the noise of EEG and its signal variations. Previous works studied time-dependent non-stationarities for BCIs in which the user's mental task was independent of the device operation (e.g., the mental task was motor imagery and the operational task was a speller). However, there are some BCIs, such as those based on error-related potentials, where the mental and operational tasks are dependent (e.g., the mental task is to assess the device action and the operational task is the device action itself). The dependence between the mental task and the device operation could introduce a new source of signal variations when the operational task changes, which has not been studied yet. The aim of this study is to analyse task-dependent signal variations and their effect on EEG error-related potentials. The work analyses the EEG variations on the three design steps of BCIs: an electrophysiology study to characterize the existence of these variations, a feature distribution analysis and a single-trial classification analysis to measure the impact on the final BCI performance. The results demonstrate that a change in the operational task produces variations in the potentials, even when EEG activity exclusively originated in brain areas related to error processing is considered. Consequently, the extracted features from the signals vary, and a classifier trained with one operational task presents a significant loss of performance for other tasks, requiring calibration or adaptation for each new task. In addition, a new calibration for each of the studied tasks rapidly outperforms adaptive techniques designed in the literature to mitigate the EEG time-dependent non-stationarities.

Task-dependent signal variations in EEG error-related potentials for brain-computer interfaces

NASA Astrophysics Data System (ADS)

Iturrate, I.; Montesano, L.; Minguez, J.

2013-04-01

Objective. A major difficulty of brain-computer interface (BCI) technology is dealing with the noise of EEG and its signal variations. Previous works studied time-dependent non-stationarities for BCIs in which the user’s mental task was independent of the device operation (e.g., the mental task was motor imagery and the operational task was a speller). However, there are some BCIs, such as those based on error-related potentials, where the mental and operational tasks are dependent (e.g., the mental task is to assess the device action and the operational task is the device action itself). The dependence between the mental task and the device operation could introduce a new source of signal variations when the operational task changes, which has not been studied yet. The aim of this study is to analyse task-dependent signal variations and their effect on EEG error-related potentials.Approach. The work analyses the EEG variations on the three design steps of BCIs: an electrophysiology study to characterize the existence of these variations, a feature distribution analysis and a single-trial classification analysis to measure the impact on the final BCI performance.Results and significance. The results demonstrate that a change in the operational task produces variations in the potentials, even when EEG activity exclusively originated in brain areas related to error processing is considered. Consequently, the extracted features from the signals vary, and a classifier trained with one operational task presents a significant loss of performance for other tasks, requiring calibration or adaptation for each new task. In addition, a new calibration for each of the studied tasks rapidly outperforms adaptive techniques designed in the literature to mitigate the EEG time-dependent non-stationarities.

Is the bipolar vessel sealer device an effective tool in robotic surgery? A retrospective analysis of our experience and a meta-analysis of the literature about different robotic procedures by investigating operative data and post-operative course.

PubMed

Ortenzi, Monica; Ghiselli, Roberto; Baldarelli, Maddalena; Cardinali, Luca; Guerrieri, Mario

2018-04-01

The latest robotic bipolar vessel sealing tools have been described to be effective allowing to perform procedures with reduced blood loss and shorter operative times. The aim of this study was to assess the efficacy and reliability of these devices applied in different robotic procedures. All robotic operations, between 2014 and 2016, were performed using the EndoWrist One VesselSealer (EWO, Intuitive Surgical, Sunnyvale, CA), a bipolar fully wristed device. Data, including age, gender, body mass index (BMI), were collected. Robot docking time, intraoperative blood loss, robot malfunctioning and overall operative time were analyzed. A meta-analysis of the literature was carried out to point the attention to three different parameters (mean blood loss, operating time and hospital stay) trying to identify how different coagulation devices may affect them. In 73 robotic procedures, the mean operative time was 118.2 minutes (75-125 minutes). Mean hospital stay was four days (2-10 days). There were two post-operative complications (2.74%). The bipolar vessel sealer offers the efficacy of bipolar diathermy and the advantages of a fully wristed instrument. It does not require any change of instruments for coagulation or involvement of the bedside assistant surgeon. These characteristics lead to a reduction in operative time.

Experimental and analytical assessment of the thermal behavior of spiral bevel gears

NASA Technical Reports Server (NTRS)

Handschuh, Robert F.; Kicher, Thomas P.

1995-01-01

An experimental and analytical study of spiral bevel gears operating in an aerospace environment has been performed. Tests were conducted within a closed loop test stand at NASA Lewis Research Center. Tests were conducted to 537 kW (720 hp) at 14,400 rpm. The effects of various operating conditions on spiral bevel gear steady state and transient temperature are presented. Also, a three-dimensional analysis of the thermal behavior was conducted using a nonlinear finite element analysis computer code. The analysis was compared to the experimental results attained in this study. The results agreed well with each other for the cases compared and were no more than 10 percent different in magnitude.

Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis.

PubMed

Park, Yoonah; Yong, Yuen Geng; Yun, Seong Hyeon; Jung, Kyung Uk; Huh, Jung Wook; Cho, Yong Beom; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

2015-05-01

This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase.

Operator function modeling: An approach to cognitive task analysis in supervisory control systems

NASA Technical Reports Server (NTRS)

Mitchell, Christine M.

1987-01-01

In a study of models of operators in complex, automated space systems, an operator function model (OFM) methodology was extended to represent cognitive as well as manual operator activities. Development continued on a software tool called OFMdraw, which facilitates construction of an OFM by permitting construction of a heterarchic network of nodes and arcs. Emphasis was placed on development of OFMspert, an expert system designed both to model human operation and to assist real human operators. The system uses a blackboard method of problem solving to make an on-line representation of operator intentions, called ACTIN (actions interpreter).

Routine versus selective contrast imaging to identify the need for early re-intervention following laparoscopic fundoplication: A retrospective cohort study.

PubMed

Shahzad, Khalid; Menon, Ashok; Turner, Paul; Ward, Jeremy; Pursnani, Kishore; Alkhaffaf, Bilal

2015-08-01

The prompt recognition of complications is essential in reducing morbidity following anti-reflux surgery. Consequently, many centres employ a policy of routine post-operative contrast studies. The study aimed to examine whether routine contrast studies more effectively recognised early post-operative complications following anti-reflux surgery compared with selective use. This was a retrospective analysis of 240 adults who had undergone primary anti-reflux surgery. Selective use of water-soluble contrast swallows was employed for 115 patients (Group 1) while 125 patients (Group 2) had routine studies. 10 (0.9%) patients from Group 1 underwent contrast studies, four (40%) of which were abnormal. Routine studies in Group 2 identified thirty-two abnormalities (27%) however the inter-group difference was not significant (p = 0.32). Only one case from group 2 required immediate re-intervention. This was not statistically significant (p = 0.78). Multivariate analysis found no significant association between selective or routine imaging and re-intervention rates. One patient from group 2 presented three days following discharge with wrap migration requiring reoperation despite a normal post-operative study. Routine use of contrast imaging following anti-reflux and hiatus hernia surgery is not necessary. It does not identify a significantly greater number of post-operative complications in comparison to selective use. Additionally, routine use of contrast studies does not ensure the diagnosis of all complications in the post-operative period. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

Lessons In Operational Art: An Analysis of the Allied Expeditionary Forces in North Russia, 1918-1919

DTIC Science & Technology

2014-04-30

operations. To identify these lessons, this monograph first reviews the origins and definitions of operational art. Next, the case study of the...commanders to consider in future expeditionary operations. To identify these lessons, this monograph first reviews the origins and definitions of...environment to better understand the problem or problems at hand.”4 The next section describes the origins and modern theoretical explanations of

Measurement and analysis of operating system fault tolerance

NASA Technical Reports Server (NTRS)

Lee, I.; Tang, D.; Iyer, R. K.

1992-01-01

This paper demonstrates a methodology to model and evaluate the fault tolerance characteristics of operational software. The methodology is illustrated through case studies on three different operating systems: the Tandem GUARDIAN fault-tolerant system, the VAX/VMS distributed system, and the IBM/MVS system. Measurements are made on these systems for substantial periods to collect software error and recovery data. In addition to investigating basic dependability characteristics such as major software problems and error distributions, we develop two levels of models to describe error and recovery processes inside an operating system and on multiple instances of an operating system running in a distributed environment. Based on the models, reward analysis is conducted to evaluate the loss of service due to software errors and the effect of the fault-tolerance techniques implemented in the systems. Software error correlation in multicomputer systems is also investigated.

The effect of family processes on school achievement as moderated by socioeconomic context.

PubMed

Oxford, Monica L; Lee, Jungeun Olivia

2011-10-01

This longitudinal study examined a model of early school achievement in reading and math, as it varies by socioeconomic context, using data from the NICHD Study of Early Child Care and Youth Development. A conceptual model was tested that included features of family stress, early parenting, and school readiness, through both a single-group analysis and also a multiple-group analysis. Latent profile analysis was used to identify subgroups of more advantaged and less advantaged families. Family stress and parenting were shown to operate differently depending on the socioeconomic context, whereas child-based school readiness characteristics were shown to operate similarly across socieodemographic contexts. Implications for intervention are discussed. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

PRT Impact Study - Operational Phase : Volume 1. Travel Analysis.

DOT National Transportation Integrated Search

1979-03-01

Part of a three-volume work, this report describes the analysis performed on travel data collected for the Pre-PRT Impact Study. The data analyzed consist of travel behavior, travel patterns, model utilization and travel costs of various modes of tra...

Theoretical Studies of Microstrip Antennas : Volume II, Analysis and Synthesis of Multi-Frequency Elements

DOT National Transportation Integrated Search

1979-09-01

Volume II of Theoretical Studies of Microstrip Antennas deals with the analysis and synthesis of several types of novel multi-resonant elements with emphasis on dual-frequency operation of rectangular microstrip patch antennas with or without externa...

Surgical problems and complex procedures: issues for operative time in robotic totally endoscopic coronary artery bypass grafting.

PubMed

Wiedemann, Dominik; Bonaros, Nikolaos; Schachner, Thomas; Weidinger, Felix; Lehr, Eric J; Vesely, Mark; Bonatti, Johannes

2012-03-01

Robotically assisted totally endoscopic coronary artery bypass grafting (TECAB) is a viable option for closed chest coronary surgery, but it requires learning curves and longer operative times. This study evaluated the effect of extended operation times on the outcome of patients undergoing TECAB. From 2001 to 2009, 325 patients underwent TECAB with the da Vinci telemanipulation system. Correlations between operative times and preoperative, intraoperative, and early postoperative parameters were investigated. Receiver operating characteristic analysis was used to define the threshold of the procedure duration above which intensive care unit stay and ventilation time were prolonged. Demographic data, intraoperative and postoperative parameters, and survival data were compared. Patients with prolonged operative times more often underwent multivessel revascularization (P < .001) and beating-heart TECAB (P =.023). Other preoperative parameters were not associated with longer operative times. Incidences of technical difficulties and conversions (P < .001) were higher among patients with longer operative times. Prolonged intensive care unit stay, mechanical ventilation, hospital stay, and with requirement of blood products were associated with longer operative times. Receiver operating characteristic analysis showed operative times >445 minutes and >478 minutes to predict prolonged (>48 hours) intensive care unit stay and mechanical ventilation, respectively. Patients with procedures >478 minutes had longer hospital stays and higher perioperative morbidity and mortality. Kaplan-Meier analysis revealed decreased survival among patients with operative times >478 minutes. Multivessel revascularization and conversions lead to prolonged operative times in totally endoscopic coronary artery bypass grafting. Longer operative times significantly influence early postoperative and midterm outcomes. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

A summary and integration of research concerning single pilot IFR operational problems

NASA Technical Reports Server (NTRS)

Chapman, G. C.

1983-01-01

A review of seven research studies pertaining to Single Pilot IFR (SPIFR) operations was performed. Two studies were based on questionnaire surveys; two based on National Transportation Safety Board (NTSB) reports; two were based on Aviation Safety Reporting System (ASRS) incident reports, and one report used event analysis and statistics to forecast problems. The results obtained in each study were extracted and integrated. Results were synthesized and key issues pertaining to SPIFR operations problems were identified. The research that was recommended by the studies and that addressed the key issues is catalogued for each key issue.

Analysis of loss of decay-heat-removal sequences at Browns Ferry Unit One

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

Harrington, R.M.

1983-01-01

This paper summarizes the Oak Ridge National Laboratory (ORNL) report Loss of DHR Sequences at Browns Ferry Unit One - Accident Sequence Analysis (NUREG/CR-2973). The Loss of DHR investigation is the third in a series of accident studies concerning the BWR 4 - MK I containment plant design. These studies, sponsored by the Nuclear Regulatory Commission Severe Accident Sequence Analysis (SASA) program, have been conducted at ORNL with the full cooperation of the Tennessee Valley Authority (TVA). The purpose of the SASA studies is to predetermine the probable course of postulated severe accidents so as to establish the timing andmore » the sequence of events. The SASA studies also produce recommendations concerning the implementation of better system design and better emergency operating instructions and operator training. The ORNL studies also include a detailed, best-estimate calculation of the release and transport of radioactive fission products following postulated severe accidents.« less

Impact of Operating Rules on Planning Capacity Expansion of Urban Water Supply Systems

NASA Astrophysics Data System (ADS)

de Neufville, R.; Galelli, S.; Tian, X.

2017-12-01

This study addresses the impact of operating rules on capacity planning of urban water supply systems. The continuous growth of metropolitan areas represents a major challenge for water utilities, which often rely on industrial water supply (e.g., desalination, reclaimed water) to complement natural resources (e.g., reservoirs). These additional sources increase the reliability of supply, equipping operators with additional means to hedge against droughts. How do their rules for using industrial water supply impact the performance of water supply system? How might it affect long-term plans for capacity expansion? Possibly significantly, as demonstrated by the analysis of the operations and planning of a water supply system inspired by Singapore. Our analysis explores the system dynamics under multiple inflow and management scenarios to understand the extent to which alternative operating rules for the use of industrial water supply affect system performance. Results first show that these operating rules can have significant impact on the variability in system performance (e.g., reliability, energy use) comparable to that of hydro-climatological conditions. Further analyses of several capacity expansion exercises—based on our original hydrological and management scenarios—show that operating rules significantly affect the timing and magnitude of critical decisions, such as the construction of new desalination plants. These results have two implications: Capacity expansion analysis should consider the effect of a priori uncertainty about operating rules; and operators should consider how their flexibility in operating rules can affect their perceived need for capacity.

Post-operative diffusion weighted imaging as a predictor of posterior fossa syndrome permanence in paediatric medulloblastoma.

PubMed

Chua, Felicia H Z; Thien, Ady; Ng, Lee Ping; Seow, Wan Tew; Low, David C Y; Chang, Kenneth T E; Lian, Derrick W Q; Loh, Eva; Low, Sharon Y Y

2017-03-01

Posterior fossa syndrome (PFS) is a serious complication faced by neurosurgeons and their patients, especially in paediatric medulloblastoma patients. The uncertain aetiology of PFS, myriad of cited risk factors and therapeutic challenges make this phenomenon an elusive entity. The primary objective of this study was to identify associative factors related to the development of PFS in medulloblastoma patient post-tumour resection. This is a retrospective study based at a single institution. Patient data and all related information were collected from the hospital records, in accordance to a list of possible risk factors associated with PFS. These included pre-operative tumour volume, hydrocephalus, age, gender, extent of resection, metastasis, ventriculoperitoneal shunt insertion, post-operative meningitis and radiological changes in MRI. Additional variables included molecular and histological subtypes of each patient's medulloblastoma tumour. Statistical analysis was employed to determine evidence of each variable's significance in PFS permanence. A total of 19 patients with appropriately complete data was identified. Initial univariate analysis did not show any statistical significance. However, multivariate analysis for MRI-specific changes reported bilateral DWI restricted diffusion changes involving both right and left sides of the surgical cavity was of statistical significance for PFS permanence. The authors performed a clinical study that evaluated possible risk factors for permanent PFS in paediatric medulloblastoma patients. Analysis of collated results found that post-operative DWI restriction in bilateral regions within the surgical cavity demonstrated statistical significance as a predictor of PFS permanence-a novel finding in the current literature.

Separation analysis, a tool for analyzing multigrid algorithms

NASA Technical Reports Server (NTRS)

Costiner, Sorin; Taasan, Shlomo

1995-01-01

The separation of vectors by multigrid (MG) algorithms is applied to the study of convergence and to the prediction of the performance of MG algorithms. The separation operator for a two level cycle algorithm is derived. It is used to analyze the efficiency of the cycle when mixing of eigenvectors occurs. In particular cases the separation analysis reduces to Fourier type analysis. The separation operator of a two level cycle for a Schridubger eigenvalue problem, is derived and analyzed in a Fourier basis. Separation analysis gives information on how to choose performance relaxations and inter-level transfers. Separation analysis is a tool for analyzing and designing algorithms, and for optimizing their performance.

Comparative Performance Analysis of Intel Xeon Phi, GPU, and CPU: A Case Study from Microscopy Image Analysis

PubMed Central

Teodoro, George; Kurc, Tahsin; Kong, Jun; Cooper, Lee; Saltz, Joel

2014-01-01

We study and characterize the performance of operations in an important class of applications on GPUs and Many Integrated Core (MIC) architectures. Our work is motivated by applications that analyze low-dimensional spatial datasets captured by high resolution sensors, such as image datasets obtained from whole slide tissue specimens using microscopy scanners. Common operations in these applications involve the detection and extraction of objects (object segmentation), the computation of features of each extracted object (feature computation), and characterization of objects based on these features (object classification). In this work, we have identify the data access and computation patterns of operations in the object segmentation and feature computation categories. We systematically implement and evaluate the performance of these operations on modern CPUs, GPUs, and MIC systems for a microscopy image analysis application. Our results show that the performance on a MIC of operations that perform regular data access is comparable or sometimes better than that on a GPU. On the other hand, GPUs are significantly more efficient than MICs for operations that access data irregularly. This is a result of the low performance of MICs when it comes to random data access. We also have examined the coordinated use of MICs and CPUs. Our experiments show that using a performance aware task strategy for scheduling application operations improves performance about 1.29× over a first-come-first-served strategy. This allows applications to obtain high performance efficiency on CPU-MIC systems - the example application attained an efficiency of 84% on 192 nodes (3072 CPU cores and 192 MICs). PMID:25419088

A Paradoxical Effect of Presession Attention on Stereotypy: Antecedent Attention as an Establishing, Not an Abolishing, Operation

ERIC Educational Resources Information Center

Roantree, Christina F.; Kennedy, Craig H.

2006-01-01

Previous studies have shown that presession attention for problem behavior can serve as an abolishing operation when attention functions as a positive reinforcer. In the current study, we show that the stereotypy of a child with severe disabilities was undifferentiated during standard analogue functional analysis conditions. However, when…

Emergency Management Operations Process Mapping: Public Safety Technical Program Study

DTIC Science & Technology

2011-02-01

Enterprise Architectures in industry, and have been successfully applied to assist companies to optimise interdependencies and relationships between...model for more in-depth analysis of EM processes, and for use in tandem with other studies that apply modeling and simulation to assess EM...for use in tandem with other studies that apply modeling and simulation to assess EM operational effectiveness before and after changing elements

Assessing team performance in the operating room: development and use of a "black-box" recorder and other tools for the intraoperative environment.

PubMed

Guerlain, Stephanie; Adams, Reid B; Turrentine, F Beth; Shin, Thomas; Guo, Hui; Collins, Stephen R; Calland, J Forrest

2005-01-01

The objective of this research was to develop a digital system to archive the complete operative environment along with the assessment tools for analysis of this data, allowing prospective studies of operative performance, intraoperative errors, team performance, and communication. Ability to study this environment will yield new insights, allowing design of systems to avoid preventable errors that contribute to perioperative complications. A multitrack, synchronized, digital audio-visual recording system (RATE tool) was developed to monitor intraoperative performance, including software to synchronize data and allow assignment of independent observational scores. Cases were scored for technical performance, participants' situational awareness (knowledge of critical information), and their comfort and satisfaction with the conduct of the procedure. Laparoscopic cholecystectomy (n = 10) was studied. Technical performance of the RATE tool was excellent. The RATE tool allowed real time, multitrack data collection of all aspects of the operative environment, while permitting digital recording of the objective assessment data in a time synchronized and annotated fashion during the procedure. The mean technical performance score was 73% +/- 28% of maximum (perfect) performance. Situational awareness varied widely among team members, with the attending surgeon typically the only team member having comprehensive knowledge of critical case information. The RATE tool allows prospective analysis of performance measures such as technical judgments, team performance, and communication patterns, offers the opportunity to conduct prospective intraoperative studies of human performance, and allows for postoperative discussion, review, and teaching. This study also suggests that gaps in situational awareness might be an underappreciated source of operative adverse events. Future uses of this system will aid teaching, failure or adverse event analysis, and intervention research.

Pre-operative indicators for mortality following hip fracture surgery: a systematic review and meta-analysis.

PubMed

Smith, Toby; Pelpola, Kelum; Ball, Martin; Ong, Alice; Myint, Phyo Kyaw

2014-07-01

hip fracture is a common and serious condition associated with high mortality. This study aimed to identify pre-operative characteristics which are associated with an increased risk of mortality after hip fracture surgery. systematic search of published and unpublished literature databases, including EMBASE, MEDLINE, AMED, CINAHL, PubMed and the Cochrane Library, was undertaken to identify all clinical studies on pre-operative predictors of mortality after surgery in hip fracture with at least 3-month follow-up. Data pertaining to the study objectives was extracted by two reviewers independently. Where study homogeneity was evidence, a meta-analysis of pooled relative risk and 95% confidence intervals was performed for mortality against pre-admission characteristics. fifty-three studies including 544,733 participants were included. Thirteen characteristics were identified as possible pre-operative indicators for mortality. Following meta-analysis, the four key characteristics associated with the risk of mortality up to 12 months were abnormal ECG (RR: 2.00; 95% CI: 1.45, 2.76), cognitive impairment (RR: 1.91; 95% CI: 1.35, 2.70), age >85 years (RR: 0.42; 95% CI: 0.20, 0.90) and pre-fracture mobility (RR: 0.13; 95% CI: 0.05, 0.34). Other statistically significant pre-fracture predictors of increased mortality were male gender, being resident in a care institution, intra-capsular fracture type, high ASA grade and high Charlson comorbidity score on admission. this review has identified the characteristics of patients with a high risk of mortality after a hip fracture surgery beyond the peri-operative period who may benefit from comprehensive assessment and appropriate management. CRD42012002107. © The Author 2014. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Space Operations Center system analysis study extension. Volume 4, book 1: SOC system analysis report

NASA Technical Reports Server (NTRS)

1982-01-01

The Space Operations Center (SOC) orbital space station missions are analyzed. Telecommunications missions, space science, Earth sensing, and space testing missions, research and applications missions, defense missions, and satellite servicing missions are modeled and mission needs discussed. The satellite servicing missions are analyzed in detail, including construction and servicing equipment requirements, mission needs and benefits, differential drag characteristics of co-orbiting satellites, and satellite servicing transportation requirements.

A Paradoxical Effect of Presession Attention on Stereotypy: Antecedent Attention as an Establishing, Not an Abolishing, Operation

PubMed Central

Roantree, Christina F; Kennedy, Craig H

2006-01-01

Previous studies have shown that presession attention for problem behavior can serve as an abolishing operation when attention functions as a positive reinforcer. In the current study, we show that the stereotypy of a child with severe disabilities was undifferentiated during standard analogue functional analysis conditions. However, when noncontingent presession attention was provided, stereotypy occurred for social attention as a positive reinforcer, suggesting that the antecedent manipulation functioned as an establishing operation. PMID:17020219

A paradoxical effect of presession attention on stereotypy: antecedent attention as an establishing, not an abolishing, operation.

PubMed

Roantree, Christina F; Kennedy, Craig H

2006-01-01

Previous studies have shown that presession attention for problem behavior can serve as an abolishing operation when attention functions as a positive reinforcer. In the current study, we show that the stereotypy of a child with severe disabilities was undifferentiated during standard analogue functional analysis conditions. However, when noncontingent presession attention was provided, stereotypy occurred for social attention as a positive reinforcer, suggesting that the antecedent manipulation functioned as an establishing operation.

Object motion analysis study

NASA Technical Reports Server (NTRS)

1974-01-01

The use of optical data processing (ODP) techniques for motion analysis in two-dimensional imagery was studied. The basic feasibility of this approach was demonstrated, but inconsistent performance of the photoplastic used for recording spatial filters prevented totally automatic operation. Promising solutions to the problems encountered are discussed, and it is concluded that ODP techniques could be quite useful for motion analysis.

National Job Corps Study: Report on the Process Analysis. Research and Evaluation Report Series.

ERIC Educational Resources Information Center

Johnson, Terry; Gritz, Mark; Jackson, Russell; Burghardt, John; Boussy, Carol; Leonard, Jan; Orians, Carlyn

This report presents results of a process analysis that describes and documents Job Corps services and operations. Chapter one provides overviews of Job Corps, the national Job Corps study, and the process analysis. Chapter two describes the administrative structure of Job Corps and presents data on the geographic distribution and characteristics…

Measurement and Modeling of Job Stress of Electric Overhead Traveling Crane Operators

PubMed Central

Krishna, Obilisetty B.; Maiti, Jhareswar; Ray, Pradip K.; Samanta, Biswajit; Mandal, Saptarshi; Sarkar, Sobhan

2015-01-01

Background In this study, the measurement of job stress of electric overhead traveling crane operators and quantification of the effects of operator and workplace characteristics on job stress were assessed. Methods Job stress was measured on five subscales: employee empowerment, role overload, role ambiguity, rule violation, and job hazard. The characteristics of the operators that were studied were age, experience, body weight, and body height. The workplace characteristics considered were hours of exposure, cabin type, cabin feature, and crane height. The proposed methodology included administration of a questionnaire survey to 76 electric overhead traveling crane operators followed by analysis using analysis of variance and a classification and regression tree. Results The key findings were: (1) the five subscales can be used to measure job stress; (2) employee empowerment was the most significant factor followed by the role overload; (3) workplace characteristics contributed more towards job stress than operator's characteristics; and (4) of the workplace characteristics, crane height was the major contributor. Conclusion The issues related to crane height and cabin feature can be fixed by providing engineering or foolproof solutions than relying on interventions related to the demographic factors. PMID:26929839

Cost analysis of injection laryngoplasty performed under local anaesthesia versus general anaesthesia: an Australian perspective.

PubMed

Chandran, D; Woods, C M; Schar, M; Ma, N; Ooi, E H; Athanasiadis, T

2018-02-01

To conduct a cost analysis of injection laryngoplasty performed in the operating theatre under local anaesthesia and general anaesthesia. The retrospective study included patients who had undergone injection laryngoplasty as day cases between July 2013 and March 2016. Cost data were obtained, along with patient demographics, anaesthetic details, type of injectant, American Society of Anesthesiologists score, length of stay, total operating theatre time and surgeon procedure time. A total of 20 cases (general anaesthesia = 6, local anaesthesia = 14) were included in the cost analysis. The mean total cost under general anaesthesia (AU$2865.96 ± 756.29) was significantly higher than that under local anaesthesia (AU$1731.61 ± 290.29) (p < 0.001). The mean operating theatre time, surgeon procedure time and length of stay were all significantly lower under local anaesthesia compared to general anaesthesia. Time variables such as operating theatre time and length of stay were the most significant predictors of the total costs. Procedures performed under local anaesthesia in the operating theatre are associated with shorter operating theatre time and length of stay in the hospital, and provide significant cost savings. Further savings could be achieved if local anaesthesia procedures were performed in the office setting.

Innovations in Site Characterization Case Study: Hanscom Air Force Base, Operable Unit 1

EPA Pesticide Factsheets

This document is a condensation of the information provided in the much more detailed Hanscom AFB Report entitled A Dynamic Site Investigation: Adaptive Sampling and Analysis Program for Operable Unit 1 at Hanscom Air Force Base, Bedford, Massachusetts.

Analysis of the capabilities and operations of the Northern Virginia Traffic Management System.

DOT National Transportation Integrated Search

1994-01-01

This report describes research to determine how the Northern Virginia Traffic Management System (TMS) operations may be improved by making modifications to the existing system. This study was completed during the period of June through September, 199...

An efficiency improvement in warehouse operation using simulation analysis

NASA Astrophysics Data System (ADS)

Samattapapong, N.

2017-11-01

In general, industry requires an efficient system for warehouse operation. There are many important factors that must be considered when designing an efficient warehouse system. The most important is an effective warehouse operation system that can help transfer raw material, reduce costs and support transportation. By all these factors, researchers are interested in studying about work systems and warehouse distribution. We start by collecting the important data for storage, such as the information on products, information on size and location, information on data collection and information on production, and all this information to build simulation model in Flexsim® simulation software. The result for simulation analysis found that the conveyor belt was a bottleneck in the warehouse operation. Therefore, many scenarios to improve that problem were generated and testing through simulation analysis process. The result showed that an average queuing time was reduced from 89.8% to 48.7% and the ability in transporting the product increased from 10.2% to 50.9%. Thus, it can be stated that this is the best method for increasing efficiency in the warehouse operation.

Quantitative computer tomography analysis of post-operative subdural fluid volume predicts recurrence of chronic subdural haematoma.

PubMed

Xu, Fei-Fan; Chen, Jin-Hong; Leung, Gilberto Ka Kit; Hao, Shu-Yu; Xu, Long; Hou, Zong-Gang; Mao, Xiang; Shi, Guang-Zhi; Li, Jing-Sheng; Liu, Bai-Yun

2014-01-01

Post-operative volume of subdural fluid is considered to correlate with recurrence in chronic subdural haematoma (CSDH). Information on the applications of computer-assisted volumetric analysis in patients with CSDHs is lacking. To investigate the relationship between haematoma recurrence and longitudinal changes in subdural fluid volume using CT volumetric analysis. Fifty-four patients harbouring 64 CSDHs were studied prospectively. The association between recurrence rate and CT findings were investigated. Eleven patients (20.4%) experienced post-operative recurrence. Higher pre-operative (over 120 ml) and/or pre-discharge subdural fluid volumes (over 22 ml) were significantly associated with recurrence; the probability of non-recurrence for values below these thresholds were 92.7% and 95.2%, respectively. CSDHs with larger pre-operative (over 15.1 mm) and/or residual (over 11.7 mm) widths also had significantly increased recurrence rates. Bilateral CSDHs were not found to be more likely to recur in this series. On receiver-operating characteristic curve, the areas under curve for the magnitude of changes in subdural fluid volume were greater than a single time-point measure of either width or volume of the subdural fluid cavity. Close imaging follow-up is important for CSDH patients for recurrence prediction. Using quantitative CT volumetric analysis, strong evidence was provided that changes in the residual fluid volume during the 'self-resolution' period can be used as significantly radiological predictors of recurrence.

A review of network analysis terminology and its application to foot-and-mouth disease modelling and policy development.

PubMed

Dubé, C; Ribble, C; Kelton, D; McNab, B

2009-04-01

Livestock movements are important in spreading infectious diseases and many countries have developed regulations that require farmers to report livestock movements to authorities. This has led to the availability of large amounts of data for analysis and inclusion in computer simulation models developed to support policy formulation. Social network analysis has become increasingly popular to study and characterize the networks resulting from the movement of livestock from farm-to-farm and through other types of livestock operations. Network analysis is a powerful tool that allows one to study the relationships created among these operations, providing information on the role that they play in acquiring and spreading infectious diseases, information that is not readily available from more traditional livestock movement studies. Recent advances in the study of real-world complex networks are now being applied to veterinary epidemiology and infectious disease modelling and control. A review of the principles of network analysis and of the relevance of various complex network theories to infectious disease modelling and control is presented in this paper.

Advanced Propulsion System Studies for General Aviation Aircraft

NASA Technical Reports Server (NTRS)

Eisenberg, Joseph D. (Technical Monitor); German, Jon

2003-01-01

This final report addresses the following topics: Market Impact Analysis (1) assessment of general aviation, including commuter/regional, aircraft market impact due to incorporation of advanced technology propulsion system on acquisition and operating costs, job creation and/or manpower demand, and future fleet size; (2) selecting an aircraft and engine for the study by focusing on the next generation 19-passenger commuter and the Williams International FJ44 turbofan engine growth. Propulsion System Analysis Conducted mission analysis studies and engine cycle analysis to define a new commuter mission and required engine performance, define acquisition and operating costs and, select engine configuration and initiated preliminary design for hardware modifications required. Propulsion System Benefits (1) assessed and defined engine emissions improvements, (2) assessed and defined noise reduction potential and, (3) conducted a cost analysis impact study. Review of Relevant NASA Programs Conducted literature searches using NERAC and NASA RECON services for related technology in the emissions and acoustics area. Preliminary Technology Development Plans Defined plan to incorporate technology improvements for an FJ44-2 growth engine in performance, emissions, and noise suppression.

Can the pre-operative Western Ontario and McMaster score predict patient satisfaction following total hip arthroplasty?

PubMed

Rogers, B A; Alolabi, B; Carrothers, A D; Kreder, H J; Jenkinson, R J

2015-02-01

In this study we evaluated whether pre-operative Western Ontario and McMaster Universities (WOMAC) osteoarthritis scores can predict satisfaction following total hip arthroplasty (THA). Prospective data for a cohort of patients undergoing THA from two large academic centres were collected, and pre-operative and one-year post-operative WOMAC scores and a 25-point satisfaction questionnaire were obtained for 446 patients. Satisfaction scores were dichotomised into either improvement or deterioration. Scatter plots and Spearman's rank correlation coefficient were used to describe the association between pre-operative WOMAC and one-year post-operative WOMAC scores and patient satisfaction. Satisfaction was compared using receiver operating characteristic (ROC) analysis against pre-operative, post-operative and δ WOMAC scores. We found no relationship between pre-operative WOMAC scores and one-year post-operative WOMAC or satisfaction scores, with Spearman's rank correlation coefficients of 0.16 and -0.05, respectively. The ROC analysis showed areas under the curve (AUC) of 0.54 (pre-operative WOMAC), 0.67 (post-operative WOMAC) and 0.43 (δ WOMAC), respectively, for an improvement in satisfaction. We conclude that the pre-operative WOMAC score does not predict the post-operative WOMAC score or patient satisfaction after THA, and that WOMAC scores can therefore not be used to prioritise patient care. ©2015 The British Editorial Society of Bone & Joint Surgery.

Comparison of posterior retroperitoneal and transabdominal lateral approaches in robotic adrenalectomy: an analysis of 200 cases.

PubMed

Kahramangil, Bora; Berber, Eren

2018-04-01

Although numerous studies have been published on robotic adrenalectomy (RA) in the literature, none has done a comparison of posterior retroperitoneal (PR) and transabdominal lateral (TL) approaches. The aim of this study was to compare the outcomes of robotic PR and TL adrenalectomy. This is a retrospective analysis of a prospectively maintained database. Between September 2008 and January 2017, perioperative outcomes of patients undergoing RA through PR and TL approaches were recorded into an IRB-approved database. Clinical and perioperative parameters were compared using Student's t test, Wilcoxon rank-sum test, and χ 2 test. Multivariate regression analysis was performed to determine factors associated with total operative time. 188 patients underwent 200 RAs. 110 patients were operated through TL and 78 patients through PR approach. Overall, conversion rate to open was 2.5% and 90-day morbidity 4.8%. The perioperative outcomes of TL and PR approaches were similar regarding estimated blood loss, rate of conversion to open, length of hospital stay, and 90-day morbidity. PR approach resulted in a shorter mean ± SD total operative time (136.3 ± 38.7 vs. 154.6 ± 48.4 min; p = 0.005) and lower visual analog scale pain score on postoperative day #1 (4.3 ± 2.5 vs. 5.4 ± 2.4; p = 0.001). After excluding tumors larger than 6 cm operated through TL approach, the difference in operative times persisted (136.3 ± 38.7 vs. 153.7 ± 45.7 min; p = 0.009). On multivariate regression analysis, increasing BMI and TL approaches were associated with longer total operative time. This study shows that robotic PR and TL approaches are equally safe and efficacious. With experience, shorter operative time and less postoperative pain can be achieved with PR technique. This supports the preferential utilization of PR approach in high-volume centers with enough experience.

[A study on the thermographic diagnosis of vibration disease of tie-tamper operators in the Japanese National Railways].

PubMed

Hirahata, H

1984-01-01

There have been many studies of thermographic diagnosis of vibration disease, but few of them seem to have discussed tie-tamping machines as a cause. This study focuses on thermographic diagnosis of vibration disease in tie-tamper operators of the Japanese National Railways. In the diagnosis the subject's both hands were immersed in water at 10 degrees C for 3 minutes before being examined. Variables such as season, age, type of vibration tool used and total operating time were considered. These were selected as outside variables and thermographic results as dependent variables, in Quantification Method II. Season and confirmation of vibration disease were found to have a relationship to thermographic scaling, but no such relationship was found for age, type of vibration tool used, or total operating time. A cross-analysis of variables confirmed the relationship with season, and revealed that there were fewer confirmed cases of vibration disease in spring and summer than in fall and winter. It was finally concluded that thermographic analysis is more reliable in colder weather.

A single pre-operative antibiotic dose is as effective as continued antibiotic prophylaxis in implant-based breast reconstruction: A matched cohort study.

PubMed

Townley, William A; Baluch, Narges; Bagher, Shaghayegh; Maass, Saskia W M C; O'Neill, Anne; Zhong, Toni; Hofer, Stefan O P

2015-05-01

Infections following implant-based breast reconstruction can lead to devastating consequences. There is currently no consensus on the need for post-operative antibiotics in preventing immediate infection. This study compared two different methods of infection prevention in this group of patients. A retrospective matched cohort study was performed on consecutive women undergoing implant-based breast reconstruction at University Health Network, Toronto (November 2008-December 2012). All patients received a single pre-operative intravenous antibiotic dose. Group A received minimal interventions and Group B underwent maximal prophylactic measures. Patient (age, smoking, diabetes, co-morbidities), oncologic and procedural variables (timing and laterality) were collected. Univariate and multivariate logistic regression were performed to compare outcomes between the two groups. Two hundred and eight patients underwent 647 implant procedures. After matching the two treatment groups by BMI, 94 patients in each treatment group yielding a total of 605 implant procedures were selected for analysis. The two groups were comparable in terms of patient and disease variables. Post-operative wound infection was similar in Group A (n = 11, 12%) compared with Group B (n = 9, 10%; p = 0.8). Univariate analysis revealed only pre-operative radiotherapy to be associated with the development of infection (0.004). Controlling for the effect of radiotherapy, multivariate analysis demonstrated that there was no statistically significant difference between the two methods for infection prevention. Our findings suggest that a single pre-operative dose of intravenous antibiotics is equally as effective as continued antibiotic prophylaxis in preventing immediate infection in patients undergoing implant-based breast reconstructions. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

A meta-analysis of the use of a transanal drainage tube to prevent anastomotic leakage after anterior resection by double-stapling technique for rectal cancer.

PubMed

Shigeta, Kohei; Okabayashi, Koji; Baba, Hideo; Hasegawa, Hirotoshi; Tsuruta, Masashi; Yamafuji, Kazuo; Kubochi, Kiyoshi; Kitagawa, Yuko

2016-02-01

The safety and efficacy of transanal drainage tube (TDT) placement to decrease the risk of postoperative anastomotic leakage after rectal cancer surgery has not been validated. The objective of this meta-analysis was to evaluate the usefulness of a TDT for the prevention of anastomotic leakage after an anterior resection for rectal cancer. The PubMed and Cochrane Library databases were searched for studies comparing TDT and non-TDT. The endpoint utilized in this study was defined as the rates of anastomotic leakage and re-operation. The relative effects of these variables were synthesized using Review Manager 5.1 software. Four trials including 909 participants (401 TDT cases and 508 non-TDT cases) met our inclusion criteria. The weighted mean anastomotic leakage rate was 4% [95% confidence interval (CI) 1-6%], and a significantly lower risk of anastomotic leakage was identified in the TDT group compared with the non-TDT group [odds ratio (OR) 0.30; 95% CI 0.16-0.55; p = 0.0001]. Furthermore, there were significant differences between the TDT and non-TDT groups in terms of the re-operation rate (OR 0.18; 95% CI 0.07-0.44; p = 0.0002). No significant covariates related to anastomotic leakage or re-operation were identified in meta-regression analysis. Both the anastomotic leakage and re-operation rates for all studies lay inside the 95% confidence interval boundaries. No visible publication bias was found by visual assessment of the funnel plot (Egger's test; anastomotic leakage: p = 0.056, re-operation: p = 0.681). Placement of a TDT is an effective and safe procedure that can decrease the rate of anastomotic leakage and re-operation after an anterior resection.

A Comprehensive Reliability Methodology for Assessing Risk of Reusing Failed Hardware Without Corrective Actions with and Without Redundancy

NASA Technical Reports Server (NTRS)

Putcha, Chandra S.; Mikula, D. F. Kip; Dueease, Robert A.; Dang, Lan; Peercy, Robert L.

1997-01-01

This paper deals with the development of a reliability methodology to assess the consequences of using hardware, without failure analysis or corrective action, that has previously demonstrated that it did not perform per specification. The subject of this paper arose from the need to provide a detailed probabilistic analysis to calculate the change in probability of failures with respect to the base or non-failed hardware. The methodology used for the analysis is primarily based on principles of Monte Carlo simulation. The random variables in the analysis are: Maximum Time of Operation (MTO) and operation Time of each Unit (OTU) The failure of a unit is considered to happen if (OTU) is less than MTO for the Normal Operational Period (NOP) in which this unit is used. NOP as a whole uses a total of 4 units. Two cases are considered. in the first specialized scenario, the failure of any operation or system failure is considered to happen if any of the units used during the NOP fail. in the second specialized scenario, the failure of any operation or system failure is considered to happen only if any two of the units used during the MOP fail together. The probability of failure of the units and the system as a whole is determined for 3 kinds of systems - Perfect System, Imperfect System 1 and Imperfect System 2. in a Perfect System, the operation time of the failed unit is the same as that of the MTO. In an Imperfect System 1, the operation time of the failed unit is assumed as 1 percent of the MTO. In an Imperfect System 2, the operation time of the failed unit is assumed as zero. in addition, simulated operation time of failed units is assumed as 10 percent of the corresponding units before zero value. Monte Carlo simulation analysis is used for this study. Necessary software has been developed as part of this study to perform the reliability calculations. The results of the analysis showed that the predicted change in failure probability (P(sub F)) for the previously failed units is as high as 49 percent above the baseline (perfect system) for the worst case. The predicted change in system P(sub F) for the previously failed units is as high as 36% for single unit failure without any redundancy. For redundant systems, with dual unit failure, the predicted change in P(sub F) for the previously failed units is as high as 16%. These results will help management to make decisions regarding the consequences of using previously failed units without adequate failure analysis or corrective action.

Performance analysis: a study using data envelopment analysis in 26 Brazilian hospitals.

PubMed

Guerra, Mariana; de Souza, Antônio Artur; Moreira, Douglas Rafael

2012-01-01

This article describes a proposal for analyzing the performance of public Brazilian hospitals using financial and non-financial rates (i.e., operational rates), and thereby highlights the effectiveness (or otherwise) of the financial management of organizations in this study. A total of 72 hospitals in the Brazilian Unified Health Care System (in Portuguese, Sistema Unico de Saúde-SUS), were selected for accessibility and completeness of their data. Twenty-six organizations were used for the study sample, consisting of entities that had publicly disclosed financial statements for the period from 2008 (in particular, via the Internet) and whose operational data could be found in the SUS database. Our proposal, based on models using the method of Data Envelopment Analysis (DEA), was the construction of six initial models that were later compiled into a standard model. The relations between the rates that comprised the models were based on the variables and the notes of: Schuhmann, McCue and Nayar, Barnum and Kutzin, Younis, Younies, and Okojie, Marinho, Moreno, and Cavalini, and Ersoy, Kavuncubasi, Ozcan, and Harris II. We put forward an enhanced grant proposal applicable to Brazil aiming to (i) confirm or refute the rates that show the effectiveness or ineffectiveness of financial management of national hospitals; and (ii) determine the best performances, which could be used as a reference for future studies. Obtained results: (i) for all financial indicators considered, only one showed no significance in all models; and (ii) for operational indicators, the results were not relevant when the number of occupied beds was considered. Though the analysis was related to only services provided by SUS, we conclude that our study has great potential for analyzing the financial management performance of Brazilian hospitals in general, for the following reasons: (i) it shows the relationship of financial and operational rates that can be used to analyze the performance of these organizations; and (ii) it introduces ranges of these values that can be used as standard for the analysis of Brazilian hospitals.

Impact of operative length on post-operative complications in meningioma surgery: a NSQIP analysis.

PubMed

Karhade, Aditya V; Fandino, Luis; Gupta, Saksham; Cote, David J; Iorgulescu, Julian B; Broekman, Marike L; Aglio, Linda S; Dunn, Ian F; Smith, Timothy R

2017-01-01

Many studies have implicated operative length as a predictor of post-operative complications, including venous thromboembolism [deep vein thrombosis (DVT) and pulmonary embolism (PE)]. We analyzed the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database from 2006 to 2014, to evaluate whether length of operation had a statistically significant effect on post-operative complications in patients undergoing surgical resection of meningioma. Patients were included for this study if they had a post-operative diagnosis of meningioma. Patient demographics, pre-operative comorbidities, and post-operative 30-day complications were analyzed. Of 3743 patients undergoing craniotomy for meningioma, 13.6 % experienced any complication. The most common complications and their median time to occurrence were urinary tract infection (2.6 %) at 10 days postoperatively (IQR 7-15), unplanned intubation (2.5 %) at 3 days (IQR 1-7), failure to wean from ventilator (2.4 %) at 2.0 days (IQR 2-4), and DVT (2.4 %) at 6 days (IQR 11-19). Postoperatively, 3.6 % developed VTE; 2.4 % developed DVT and 1.7 % developed PE. Multivariable analysis identified older age (third and upper quartile), obesity, preoperative ventilator dependence, preoperative steroid use, anemia, and longer operative time as significant risk factors for VTE. Separate multivariable logistic regression models demonstrated longer operative time as a significant risk factor for VTE, all complications, major complications, and minor complications. Meningioma resection is associated with various post-operative complications that increase patient morbidity and mortality risk. this large, multi-institutional patient sample, longer operative length was associated with increased risk for postoperative venous thromboembolisms, as well as major and minor complications.

Modeling and Simulation of Avionics Systems and Command, Control and Communications Systems

DTIC Science & Technology

1980-01-01

analytical and operational talent into a cohesive study group . This group becomes our critical mass for innovative analysis. For command and control problems...that focusing small integrated groups on specific aspects of a command and control problem sucoseds best. For example, Air Force Studies and Analyses...phase so called " study groups " should define "tactical requirement-papers", These study groups will be supported by operational analyses and by

[Comparative evolution surgical accesses to temporo-mandibular joint].

PubMed

Sysoliatin, P G; Novikov, A I; Sysoliatin, S P; Bobylev, N G; Brega, I N

2007-01-01

In experiment on 30 corpses of adult people criteria of an operational wound (depth of a wound, a corner of operational action, an axis of operational action, a corner of an inclination of operational action) were studied at preauricularis, intrauricularis, intrauriculo-temporalis and posterior mandibullaris access to temporo-mandibular joint (TMJ). New surgical intrauriculo-temporalis access to the joint is substantrated. On the basis of the analysis of 289 operations at 268 patients the indications to a choice of surgical access were developed at various diseases and damages of TMJ.

Cell module and fuel conditioner development

NASA Technical Reports Server (NTRS)

Feret, J. M.

1981-01-01

A phosphoric acid fuel cell (PAFC) stack design having a 10 kW power rating for operation at higher than atmospheric pressure based on the existing Mark II design configuration is described. Functional analysis, trade studies and thermodynamic cycle analysis for requirements definition and system operating parameter selection purposes were performed. Fuel cell materials and components, and performance testing and evaluation of the repeating electrode components were characterized. The state of the art manufacturing technology for all fuel cell components and the fabrication of short stacks of various sites were established. A 10 kW PAFC stack design for higher pressure operation utilizing the top down systems engineering aproach was developed.

Analysis of RHIC beam dump pre-fires

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

Zhang, W.; Ahrens, L.; Fischer, W.

2011-03-28

It has been speculated that the beam may cause instability of the RHIC Beam Abort Kickers. In this study, we explore the available data of past beam operations, the device history of key modulator components, and the radiation patterns to examine the correlations. The RHIC beam abort kicker system was designed and built in the 90's. Over last decade, we have made many improvements to bring the RHIC beam abort kicker system to a stable operational state. However, the challenge continues. We present the analysis of the pre-fire, an unrequested discharge of kicker, issues which relates to the RHIC machinemore » safety and operational stability.« less

Carbon/graphite fiber risk analysis and assessment study: Assessment of risk to the Lockheed Model L-1011 commercial transport aircraft

NASA Technical Reports Server (NTRS)

Daniledes, J.; Koch, J. R.

1980-01-01

The risk associated with the accidental release of carbon/graphite fibers (CF) from fires on commercial transport aircraft incorporating composite materials was assessed. Data are developed to evaluate the potential for CF damage to electrical and electronic equipment, assess the cost risk, and evaluate the hazard to continued operation. The subjects covered include identification of susceptible equipments, determination of infiltration transfer functions, analysis of airport operations, calculation of probabilities of equipment failures, assessment of the cost risk, and evaluation of the hazard to continued operation. The results show the risks associated with CF contamination are negligible through 1993.

Detection of gastric cancer-associated microRNAs on microRNA microarray comparing pre- and post-operative plasma

PubMed Central

Konishi, H; Ichikawa, D; Komatsu, S; Shiozaki, A; Tsujiura, M; Takeshita, H; Morimura, R; Nagata, H; Arita, T; Kawaguchi, T; Hirashima, S; Fujiwara, H; Okamoto, K; Otsuji, E

2012-01-01

Background: Recently, it was reported that plasma microRNAs (miRNAs) are low-invasive useful biomarkers for cancer. We attempted to isolate gastric cancer (GC)-associated miRNAs comparing pre- and post-operative paired plasma, thereby excluding the possible effects of individual variability. Methods: This study was divided into four steps: (1) microarray analysis comparing pre- and post-operative plasma; (2) validation of candidate miRNAs by quantitative RT–PCR; (3) validation study of selected miRNAs using paired plasma; and (4) comparison of the levels of selected miRNAs in plasma between healthy controls and patients. Results: From the results of microarray analysis, nine candidate miRNAs the levels of which were markedly decreased in post-operative plasma were selected for further studies. After confirmation of their post-operative marked reduction, two candidate miRNAs, miR-451 and miR-486, were selected as plasma biomarkers, considering the abundance in plasma, and marked decrease in post-operative samples. In validation, the two miRNAs were found to decrease in post-operative plasma in 90 and 93% of patients (both P<0.01). In comparison with healthy controls, the levels of both miRNAs were found to be significantly higher in patients, and the area under the curve values were high at 0.96 and 0.92. Conclusion: Plasma miR-451 and miR-486 could be useful blood-based biomarkers for screening GC. PMID:22262318

Reliability analysis of a wastewater treatment plant using fault tree analysis and Monte Carlo simulation.

PubMed

Taheriyoun, Masoud; Moradinejad, Saber

2015-01-01

The reliability of a wastewater treatment plant is a critical issue when the effluent is reused or discharged to water resources. Main factors affecting the performance of the wastewater treatment plant are the variation of the influent, inherent variability in the treatment processes, deficiencies in design, mechanical equipment, and operational failures. Thus, meeting the established reuse/discharge criteria requires assessment of plant reliability. Among many techniques developed in system reliability analysis, fault tree analysis (FTA) is one of the popular and efficient methods. FTA is a top down, deductive failure analysis in which an undesired state of a system is analyzed. In this study, the problem of reliability was studied on Tehran West Town wastewater treatment plant. This plant is a conventional activated sludge process, and the effluent is reused in landscape irrigation. The fault tree diagram was established with the violation of allowable effluent BOD as the top event in the diagram, and the deficiencies of the system were identified based on the developed model. Some basic events are operator's mistake, physical damage, and design problems. The analytical method is minimal cut sets (based on numerical probability) and Monte Carlo simulation. Basic event probabilities were calculated according to available data and experts' opinions. The results showed that human factors, especially human error had a great effect on top event occurrence. The mechanical, climate, and sewer system factors were in subsequent tier. Literature shows applying FTA has been seldom used in the past wastewater treatment plant (WWTP) risk analysis studies. Thus, the developed FTA model in this study considerably improves the insight into causal failure analysis of a WWTP. It provides an efficient tool for WWTP operators and decision makers to achieve the standard limits in wastewater reuse and discharge to the environment.

Albumin, a marker for post-operative myocardial damage in cardiac surgery.

PubMed

van Beek, Dianne E C; van der Horst, Iwan C C; de Geus, A Fred; Mariani, Massimo A; Scheeren, Thomas W L

2018-06-06

Low serum albumin (SA) is a prognostic factor for poor outcome after cardiac surgery. The aim of this study was to estimate the association between pre-operative SA, early post-operative SA and postoperative myocardial injury. This single center cohort study included adult patients undergoing cardiac surgery during 4 consecutive years. Postoperative myocardial damage was defined by calculating the area under the curve (AUC) of troponin (Tn) values during the first 72 h after surgery and its association with SA analyzed using linear regression and with multivariable linear regression to account for patient related and procedural confounders. The association between SA and the secondary outcomes (peri-operative myocardial infarction [PMI], requiring ventilation >24 h, rhythm disturbances, 30-day mortality) was studied using (multivariable) log binomial regression analysis. In total 2757 patients were included. The mean pre-operative SA was 29 ± 13 g/l and the mean post-operative SA was 26 ± 6 g/l. Post-operative SA levels (on average 26 min after surgery) were inversely associated with postoperative myocardial damage in both univariable analysis (regression coefficient - 0.019, 95%CI -0.022/-0.015, p < 0.005) and after adjustment for patient related and surgical confounders (regression coefficient - 0.014 [95% CI -0.020/-0.008], p < 0.0005). Post-operative albumin levels were significantly correlated with the amount of postoperative myocardial damage in patients undergoing cardiac surgery independent of typical confounders. Copyright © 2018. Published by Elsevier Inc.

Operation analysis of a Chebyshev-Pantograph leg mechanism for a single DOF biped robot

NASA Astrophysics Data System (ADS)

Liang, Conghui; Ceccarelli, Marco; Takeda, Yukio

2012-12-01

In this paper, operation analysis of a Chebyshev-Pantograph leg mechanism is presented for a single degree of freedom (DOF) biped robot. The proposed leg mechanism is composed of a Chebyshev four-bar linkage and a pantograph mechanism. In contrast to general fully actuated anthropomorphic leg mechanisms, the proposed leg mechanism has peculiar features like compactness, low-cost, and easy-operation. Kinematic equations of the proposed leg mechanism are formulated for a computer oriented simulation. Simulation results show the operation performance of the proposed leg mechanism with suitable characteristics. A parametric study has been carried out to evaluate the operation performance as function of design parameters. A prototype of a single DOF biped robot equipped with two proposed leg mechanisms has been built at LARM (Laboratory of Robotics and Mechatronics). Experimental test shows practical feasible walking ability of the prototype, as well as drawbacks are discussed for the mechanical design.

Experimental study of high density foods for the Space Operations Center

NASA Technical Reports Server (NTRS)

Ahmed, S. M.

1981-01-01

The experimental study of high density foods for the Space Operations Center is described. A sensory evaluation of the high density foods was conducted first to test the acceptability of the products. A shelf-life study of the high density foods was also conducted for three different time lengths at three different temperatures. The nutritional analysis of the high density foods is at present incomplete.

Predicting Employment Outcomes of Consumers of State-Operated Comprehensive Rehabilitation Centers

ERIC Educational Resources Information Center

Beach, David Thomas

2009-01-01

This study used records from a state-operated comprehensive rehabilitation center to investigate possible predictive factors related to completing comprehensive rehabilitation center programs and successful vocational rehabilitation (VR) case closure. An analysis of demographic data of randomly selected comprehensive rehabilitation center…

Space tug economic analysis study. Volume 3: Cost estimates

NASA Technical Reports Server (NTRS)

1972-01-01

Cost estimates for the space tug operation are presented. The subjects discussed are: (1) research and development costs, (2) investment costs, (3) operations costs, and (4) funding requirements. The emphasis is placed on the single stage tug configuration using various types of liquid propellants.

Operational improvements at traffic circles : safety analysis, final report, December 2008.

DOT National Transportation Integrated Search

2008-12-01

The purpose of this study was to improve the safety and operation at three traffic circles in New : Jersey. To do this, data were collected at the traffic circles to allow researchers to model the : circles using the PARAMICS software simulation pack...

Satellite power systems (SPS) concept definition study. Volume 7: SPS program plan and economic analysis, appendixes

NASA Technical Reports Server (NTRS)

Hanley, G.

1978-01-01

Three appendixes in support of Volume 7 are contained in this document. The three appendixes are: (1) Satellite Power System Work Breakdown Structure Dictionary; (2) SPS cost Estimating Relationships; and (3) Financial and Operational Concept. Other volumes of the final report that provide additional detail are: Executive Summary; SPS Systems Requirements; SPS Concept Evolution; SPS Point Design Definition; Transportation and Operations Analysis; and SPS Technology Requirements and Verification.

Microwave power transmission system studies. Volume 3, section 8: Mechanical systems and flight operations

NASA Technical Reports Server (NTRS)

Maynard, O. E.; Brown, W. C.; Edwards, A.; Haley, J. T.; Meltz, G.; Howell, J. M.; Nathan, A.

1975-01-01

The efforts and recommendations associated with preliminary design and concept definition for mechanical systems and flight operations are presented. Technical discussion in the areas of mission analysis, antenna structural concept, configuration analysis, assembly and packaging with associated costs are presented. Technology issues for the control system, structural system, thermal system and assembly including cost and man's role in assembly and maintenance are identified. Background and desired outputs for future efforts are discussed.

Model-Based Systems Engineering With the Architecture Analysis and Design Language (AADL) Applied to NASA Mission Operations

NASA Technical Reports Server (NTRS)

Munoz Fernandez, Michela Miche

2014-01-01

The potential of Model Model Systems Engineering (MBSE) using the Architecture Analysis and Design Language (AADL) applied to space systems will be described. AADL modeling is applicable to real-time embedded systems- the types of systems NASA builds. A case study with the Juno mission to Jupiter showcases how this work would enable future missions to benefit from using these models throughout their life cycle from design to flight operations.

Development of Improved Caprock Integrity and Risk Assessment Techniques

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

Bruno, Michael

GeoMechanics Technologies has completed a geomechanical caprock integrity analysis and risk assessment study funded through the US Department of Energy. The project included: a detailed review of historical caprock integrity problems experienced in the natural gas storage industry; a theoretical description and documentation of caprock integrity issues; advanced coupled transport flow modelling and geomechanical simulation of three large-scale potential geologic sequestration sites to estimate geomechanical effects from CO₂ injection; development of a quantitative risk and decision analysis tool to assess caprock integrity risks; and, ultimately the development of recommendations and guidelines for caprock characterization and CO₂ injection operating practices. Historicalmore » data from gas storage operations and CO₂ sequestration projects suggest that leakage and containment incident risks are on the order of 10-1 to 10-2, which is higher risk than some previous studies have suggested for CO₂. Geomechanical analysis, as described herein, can be applied to quantify risks and to provide operating guidelines to reduce risks. The risk assessment tool developed for this project has been applied to five areas: The Wilmington Graben offshore Southern California, Kevin Dome in Montana, the Louden Field in Illinois, the Sleipner CO₂ sequestration operation in the North Sea, and the In Salah CO₂ sequestration operation in North Africa. Of these five, the Wilmington Graben area represents the highest relative risk while the Kevin Dome area represents the lowest relative risk.« less

A strategy for low cost development of incremental oil in legacy reservoirs

USGS Publications Warehouse

Attanasi, E.D.

2016-01-01

The precipitous decline in oil prices during 2015 has forced operators to search for ways to develop low-cost and low-risk oil reserves. This study examines strategies to low cost development of legacy reservoirs, particularly those which have already implemented a carbon dioxide enhanced oil recovery (CO2 EOR) program. Initially the study examines the occurrence and nature of the distribution of the oil resources that are targets for miscible and near-miscible CO2 EOR programs. The analysis then examines determinants of technical recovery through the analysis of representative clastic and carbonate reservoirs. The economic analysis focusses on delineating the dominant components of investment and operational costs. The concluding sections describe options to maximize the value of assets that the operator of such a legacy reservoir may have that include incremental expansion within the same producing zone and to producing zones that are laterally or stratigraphically near main producing zones. The analysis identified the CO2 recycle plant as the dominant investment cost item and purchased CO2 and liquids management as a dominant operational cost items. Strategies to utilize recycle plants for processing CO2 from multiple producing zones and multiple reservoir units can significantly reduce costs. Industrial sources for CO2 should be investigated as a possibly less costly way of meeting EOR requirements. Implementation of tapered water alternating gas injection schemes can partially mitigate increases in fluid lifting costs.

Progress in Operational Analysis of Launch Vehicles in Nonstationary Flight

NASA Technical Reports Server (NTRS)

James, George; Kaouk, Mo; Cao, Timothy

2013-01-01

This paper presents recent results in an ongoing effort to understand and develop techniques to process launch vehicle data, which is extremely challenging for modal parameter identification. The primary source of difficulty is due to the nonstationary nature of the situation. The system is changing, the environment is not steady, and there is an active control system operating. Hence, the primary tool for producing clean operational results (significant data lengths and data averaging) is not available to the user. This work reported herein uses a correlation-based two step operational modal analysis approach to process the relevant data sets for understanding and development of processes. A significant drawback for such processing of short time histories is a series of beating phenomena due to the inability to average out random modal excitations. A recursive correlation process coupled to a new convergence metric (designed to mitigate the beating phenomena) is the object of this study. It has been found in limited studies that this process creates clean modal frequency estimates but numerically alters the damping.

Discomfort analysis in computerized numeric control machine operations.

PubMed

Muthukumar, Krishnamoorthy; Sankaranarayanasamy, Krishnasamy; Ganguli, Anindya Kumar

2012-06-01

The introduction of computerized numeric control (CNC) technology in manufacturing industries has revolutionized the production process, but there are some health and safety problems associated with these machines. The present study aimed to investigate the extent of postural discomfort in CNC machine operators, and the relationship of this discomfort to the display and control panel height, with a view to validate the anthropometric recommendation for the location of the display and control panel in CNC machines. The postural discomforts associated with CNC machines were studied in 122 male operators using Corlett and Bishop's body part discomfort mapping, subject information, and discomfort level at various time intervals from starting to end of a shift. This information was collected using a questionnaire. Statistical analysis was carried out using ANOVA. Neck discomfort due to the positioning of the machine displays, and shoulder and arm discomfort due to the positioning of controls were identified as common health issues in the operators of these machines. The study revealed that 45.9% of machine operators reported discomfort in the lower back, 41.8% in the neck, 22.1% in the upper-back, 53.3% in the shoulder and arm, and 21.3% of the operators reported discomfort in the leg. Discomfort increased with the progress of the day and was highest at the end of a shift; subject age had no effect on patient tendency to experience discomfort levels.

Modeling, control, and dynamic performance analysis of a reverse osmosis desalination plant integrated within hybrid energy systems

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

Kim, Jong Suk; Chen, Jun; Garcia, Humberto E.

An RO (reverse osmosis) desalination plant is proposed as an effective, FLR (flexible load resource) to be integrated into HES (hybrid energy systems) to support various types of ancillary services to the electric grid, under variable operating conditions. To study the dynamic (transient) analysis of such system, among the various unit operations within HES, special attention is given here to the detailed dynamic modeling and control design of RO desalination process with a spiral-wound membrane module. The model incorporates key physical phenomena that have been investigated individually into a dynamic integrated model framework. In particular, the solution-diffusion model modified withmore » the concentration polarization theory is applied to predict RO performance over a large range of operating conditions. Simulation results involving several case studies suggest that an RO desalination plant, acting as a FLR, can provide operational flexibility to participate in energy management at the utility scale by dynamically optimizing the use of excess electrical energy. Here, the incorporation of additional commodity (fresh water) produced from a FLR allows a broader range of HES operations for maximizing overall system performance and profitability. For the purpose of assessing the incorporation of health assessment into process operations, an online condition monitoring approach for RO membrane fouling supervision is addressed in the case study presented.« less

Modeling, control, and dynamic performance analysis of a reverse osmosis desalination plant integrated within hybrid energy systems

DOE PAGES

Kim, Jong Suk; Chen, Jun; Garcia, Humberto E.

2016-06-17

An RO (reverse osmosis) desalination plant is proposed as an effective, FLR (flexible load resource) to be integrated into HES (hybrid energy systems) to support various types of ancillary services to the electric grid, under variable operating conditions. To study the dynamic (transient) analysis of such system, among the various unit operations within HES, special attention is given here to the detailed dynamic modeling and control design of RO desalination process with a spiral-wound membrane module. The model incorporates key physical phenomena that have been investigated individually into a dynamic integrated model framework. In particular, the solution-diffusion model modified withmore » the concentration polarization theory is applied to predict RO performance over a large range of operating conditions. Simulation results involving several case studies suggest that an RO desalination plant, acting as a FLR, can provide operational flexibility to participate in energy management at the utility scale by dynamically optimizing the use of excess electrical energy. Here, the incorporation of additional commodity (fresh water) produced from a FLR allows a broader range of HES operations for maximizing overall system performance and profitability. For the purpose of assessing the incorporation of health assessment into process operations, an online condition monitoring approach for RO membrane fouling supervision is addressed in the case study presented.« less

Discomfort Analysis in Computerized Numeric Control Machine Operations

PubMed Central

Sankaranarayanasamy, Krishnasamy; Ganguli, Anindya Kumar

2012-01-01

Objectives The introduction of computerized numeric control (CNC) technology in manufacturing industries has revolutionized the production process, but there are some health and safety problems associated with these machines. The present study aimed to investigate the extent of postural discomfort in CNC machine operators, and the relationship of this discomfort to the display and control panel height, with a view to validate the anthropometric recommendation for the location of the display and control panel in CNC machines. Methods The postural discomforts associated with CNC machines were studied in 122 male operators using Corlett and Bishop's body part discomfort mapping, subject information, and discomfort level at various time intervals from starting to end of a shift. This information was collected using a questionnaire. Statistical analysis was carried out using ANOVA. Results Neck discomfort due to the positioning of the machine displays, and shoulder and arm discomfort due to the positioning of controls were identified as common health issues in the operators of these machines. The study revealed that 45.9% of machine operators reported discomfort in the lower back, 41.8% in the neck, 22.1% in the upper-back, 53.3% in the shoulder and arm, and 21.3% of the operators reported discomfort in the leg. Conclusion Discomfort increased with the progress of the day and was highest at the end of a shift; subject age had no effect on patient tendency to experience discomfort levels. PMID:22993720

Teamwork and error in the operating room: analysis of skills and roles.

PubMed

Catchpole, K; Mishra, A; Handa, A; McCulloch, P

2008-04-01

To analyze the effects of surgical, anesthetic, and nursing teamwork skills on technical outcomes. The value of team skills in reducing adverse events in the operating room is presently receiving considerable attention. Current work has not yet identified in detail how the teamwork and communication skills of surgeons, anesthetists, and nurses affect the course of an operation. Twenty-six laparoscopic cholecystectomies and 22 carotid endarterectomies were studied using direct observation methods. For each operation, teams' skills were scored for the whole team, and for nursing, surgical, and anesthetic subteams on 4 dimensions (leadership and management [LM]; teamwork and cooperation; problem solving and decision making; and situation awareness). Operating time, errors in surgical technique, and other procedural problems and errors were measured as outcome parameters for each operation. The relationships between teamwork scores and these outcome parameters within each operation were examined using analysis of variance and linear regression. Surgical (F(2,42) = 3.32, P = 0.046) and anesthetic (F(2,42) = 3.26, P = 0.048) LM had significant but opposite relationships with operating time in each operation: operating time increased significantly with higher anesthetic but decreased with higher surgical LM scores. Errors in surgical technique had a strong association with surgical situation awareness (F(2,42) = 7.93, P < 0.001) in each operation. Other procedural problems and errors were related to the intraoperative LM skills of the nurses (F(5,1) = 3.96, P = 0.027). Detailed analysis of team interactions and dimensions is feasible and valuable, yielding important insights into relationships between nontechnical skills, technical performance, and operative duration. These results support the concept that interventions designed to improve teamwork and communication may have beneficial effects on technical performance and patient outcome.

Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis

PubMed Central

Park, Yoonah; Yong, Yuen Geng; Jung, Kyung Uk; Huh, Jung Wook; Cho, Yong Beom; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

2015-01-01

Purpose This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). Methods This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. Results Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). Conclusion The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase. PMID:25960990

Post-operative bracing after pedicle screw fixation for thoracolumbar burst fractures: A cost-effectiveness study.

PubMed

Piazza, Matthew; Sinha, Saurabh; Agarwal, Prateek; Mallela, Arka; Nayak, Nikhil; Schuster, James; Stein, Sherman

2017-11-01

While frequently prescribed to patients following fixation for spine trauma, the utility of spinal orthoses during the post-operative period is poorly described in the literature. In this study, we calculated rates of reoperation and performed a decision analysis to determine the utility of bracing following pedicle screw fixation for thoracic and lumbar burst fractures. Pubmed was searched for articles published between 2005 and 2015 for terms related to pedicle screw fixation of thoracolumbar fractures. Additionally, a database of neurosurgical patients operated on within the authors institution was also used in the analysis. Incidences of significant adverse events (wound revision for either dehiscence or infection or re-operation for non-union or instability due to hardware failure) were determined. Pooled means and variances of reported parameters were obtained using a random-effects, inverse variance meta-analytic model for observational data. Utilities for surgical outcome and complications were assigned using previously published values. Of the 225 abstracts reviewed, 48 articles were included in the study, yielding a total of 1957 patients. After including patients from the institutional registry, together a total of 2081 patients were included in the final analysis, 1328 of whom were braced. Non-braced patients were older then braced patients, although this only approached significance (p=0.051). Braced patients had significantly lower rates of re-operation for non-union or clinically significant hardware failure (1.3% vs. 1.8%, p<0.001) although the groups had comparable rates of operative wound dehiscence and infection (p=1.000). These two approaches yielded comparable utility scores (p=0.120). Costs between braced and non-braced patients were comparable excluding the cost of the brace (p=0.256); hence, the added cost of the brace suggests that bracing post-operatively is not a cost effective measure. Bracing following operative stabilization of thoracolumbar fracture does not significantly improve stability, nor does it increase wound complications. Moreover, our data suggests that post-operative bracing may not be a cost-effective measure. Copyright © 2017. Published by Elsevier Ltd.

Aeromechanics Analysis of a Distortion-Tolerant Fan with Boundary Layer Ingestion

NASA Technical Reports Server (NTRS)

Bakhle, Milind A.; Reddy, T. S. R.; Coroneos, Rula M.; Min, James B.; Provenza, Andrew J.; Duffy, Kirsten P.; Stefko, George L.; Heinlein, Gregory S.

2018-01-01

A propulsion system with Boundary Layer Ingestion (BLI) has the potential to significantly reduce aircraft engine fuel burn. But a critical challenge is to design a fan that can operate continuously with a persistent BLI distortion without aeromechanical failure -- flutter or high cycle fatigue due to forced response. High-fidelity computational aeromechanics analysis can be very valuable to support the design of a fan that has satisfactory aeromechanic characteristics and good aerodynamic performance and operability. Detailed aeromechanics analyses together with careful monitoring of the test article is necessary to avoid unexpected problems or failures during testing. In the present work, an aeromechanics analysis based on a three-dimensional, time-accurate, Reynolds-averaged Navier-Stokes computational fluid dynamics code is used to study the performance and aeromechanical characteristics of the fan in both circumferentially-uniform and circumferentially-varying distorted flows. Pre-test aeromechanics analyses are used to prepare for the wind tunnel test and comparisons are made with measured blade vibration data after the test. The analysis shows that the fan has low levels of aerodynamic damping at various operating conditions examined. In the test, the fan remained free of flutter except at one near-stall operating condition. Analysis could not be performed at this low mass flow rate operating condition since it fell beyond the limit of numerical stability of the analysis code. The measured resonant forced response at a specific low-response crossing indicated that the analysis under-predicted this response and work is in progress to understand possible sources of differences and to analyze other larger resonant responses. Follow-on work is also planned with a coupled inlet-fan aeromechanics analysis that will more accurately represent the interactions between the fan and BLI distortion.

Performance analysis of a SOFC under direct internal reforming conditions

NASA Astrophysics Data System (ADS)

Janardhanan, Vinod M.; Heuveline, Vincent; Deutschmann, Olaf

This paper presents the performance analysis of a planar solid-oxide fuel cell (SOFC) under direct internal reforming conditions. A detailed solid-oxide fuel cell model is used to study the influences of various operating parameters on cell performance. Significant differences in efficiency and power density are observed for isothermal and adiabatic operational regimes. The influence of air number, specific catalyst area, anode thickness, steam to carbon (s/c) ratio of the inlet fuel, and extend of pre-reforming on cell performance is analyzed. In all cases except for the case of pre-reformed fuel, adiabatic operation results in lower performance compared to isothermal operation. It is further discussed that, though direct internal reforming may lead to cost reduction and increased efficiency by effective utilization of waste heat, the efficiency of the fuel cell itself is higher for pre-reformed fuel compared to non-reformed fuel. Furthermore, criteria for the choice of optimal operating conditions for cell stacks operating under direct internal reforming conditions are discussed.

Management of blunt pancreatic trauma in children: Review of the National Trauma Data Bank☆,☆☆

PubMed Central

Englum, Brian R.; Gulack, Brian C.; Rice, Henry E.; Scarborough, John E.; Adibe, Obinna O.

2016-01-01

Purpose This study aims to examine the current management strategies and outcomes after blunt pancreatic trauma in children using a national patient registry. Methods Using the National Trauma Data Bank (NTDB) from 2007–2011, we identified all patients ≤18 years old who suffered blunt pancreatic trauma. Patients were categorized as undergoing nonoperative pancreatic management (no abdominal operation, abdominal operation without pancreatic-specific procedure, or pancreatic drainage alone) or operative pancreatic management (pancreatic resection/repair). Patient characteristics, operative details, clinical outcomes, and factors associated with operative management were examined. Results Of 610,402 pediatric cases in the NTDB, 1653 children (0.3%) had blunt pancreatic injury and 674 had information on specific location of pancreatic injury. Of these 674 cases, 514 (76.3%) underwent nonoperative pancreatic management. The groups were similar in age, gender, and race; however, pancreatic injury grade > 3, moderate to severe injury severity, and bicycle accidents were associated with operative management in multivariable analysis. Children with pancreatic head injuries or GCS motor score < 6 were less likely to undergo pancreatic operation. Overall morbidity and mortality rates were 26.5% and 5.3%, respectively. Most outcomes were similar between treatment groups, including mortality (2.5% vs. 6.7% in operative vs. nonoperative cohorts respectively; p = 0.07). Conclusion Although rare, blunt pancreatic trauma in children continues to be a morbid injury. In the largest analysis of blunt pancreatic trauma in children, we provide data on which to base future prospective studies. Operative management of pancreatic trauma occurs most often in children with distal ductal injuries, suggesting that prospective studies may want to focus on this group. PMID:27577183

Safety of remifentanil in transsphenoidal surgery: A single-center analysis of 540 patients.

PubMed

Cote, David J; Burke, William T; Castlen, Joseph P; King, Chih H; Zaidi, Hasan A; Smith, Timothy R; Laws, Edward R; Aglio, Linda S

2017-04-01

Although some studies have examined the efficacy and safety of remifentanil in patients undergoing neurosurgical procedures, none has examined its safety in transsphenoidal operations specifically. In this study, all transsphenoidal operations performed by a single author from 2008 to 2015 were retrospectively reviewed to evaluate the safety of remifentanil in a consecutive series of patients. During the study period, 540 transsphenoidal operations were identified. Of these, 443 (82.0%) patients received remifentanil intra-operatively; 97 (18.0%) did not. The two groups were well-matched with regard to demographic categories, comorbidities, and pre-operative medications (p>0.05), except pre-operative tobacco use (p=0.021). Patients were also well-matched with regard to radiographic features and surgical techniques. Patients who received remifentanil were more likely to harbor a macroadenoma (78.1% vs. 67.0%, p=0.025), and had slightly longer anesthesia time on average (269.2minvs. 239.4min, p=0.024). All pathologic diagnoses were well-matched between the two groups, except that patients receiving remifentanil were more likely to harbor a non-functioning adenoma (46.5% vs. 26.8%, p<0.001). Analysis of post-operative complications showed no significant difference between patients who received remifentanil and those who did not, and length of stay and prevalence of ICU stay did not differ between the two groups. In a well-matched series of 540 patients undergoing transsphenoidal surgery, remifentanil was found to be a safe anesthetic adjunct. There were no significant differences in post-operative hospital course or complications in patients who did and did not receive intra-operative remifentanil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Improving tractor safety warnings: readability is missing.

PubMed

Tebeaux, E

2010-07-01

Research on tractor safety has not focused on user manuals. This study focuses on tractor operator manuals, specifically safety warnings, selected from the files of the Tractor Test facility at University of Nebraska-Lincoln. Analysis of many common warnings, based on readability and legibility research, shows that many warnings contain excessive information, confusing visuals and safety icons, poor document design, and illegible typefaces. The result is unreadable warnings that do not communicate quickly and correctly, and discourage readers rather than clarify critical information. Many tractor operator warnings are cluttered, "over-written," and contain information needed to protect the manufacturer rather than to inform operators. What is needed is a careful analysis and revision of many safety warnings with the goal of encouraging operators to read the warnings and follow their message.

WFIRST: STScI Science Operations Center (SSOC) Activities and Plans

NASA Astrophysics Data System (ADS)

Gilbert, Karoline M.; STScI WFIRST Team

2018-01-01

The science operations for the WFIRST Mission will be distributed between Goddard Space Flight Center, the Space Telescope Science Institute (STScI), and the Infrared Processing and Analysis Center (IPAC). The STScI Science Operations Center (SSOC) will schedule and archive all WFIRST observations, will calibrate and produce pipeline-reduced data products for the Wide Field Instrument, and will support the astronomical community in planning WFI observations and analyzing WFI data. During the formulation phase, WFIRST team members at STScI have developed operations concepts for scheduling, data management, and the archive; have performed technical studies investigating the impact of WFIRST design choices on data quality and analysis; and have built simulation tools to aid the community in exploring WFIRST’s capabilities. We will highlight examples of each of these efforts.

Human Factors Vehicle Displacement Analysis: Engineering In Motion

NASA Technical Reports Server (NTRS)

Atencio, Laura Ashley; Reynolds, David; Robertson, Clay

2010-01-01

While positioned on the launch pad at the Kennedy Space Center, tall stacked launch vehicles are exposed to the natural environment. Varying directional winds and vortex shedding causes the vehicle to sway in an oscillating motion. The Human Factors team recognizes that vehicle sway may hinder ground crew operation, impact the ground system designs, and ultimately affect launch availability . The objective of this study is to physically simulate predicted oscillation envelopes identified by analysis. and conduct a Human Factors Analysis to assess the ability to carry out essential Upper Stage (US) ground operator tasks based on predicted vehicle motion.

Study to determine the IFR operational profile and problems to the general aviation pilot

NASA Technical Reports Server (NTRS)

Weislogel, S.

1983-01-01

A study of the general aviation single pilot operating under instrument flight rules (GA SPIFR) has been conducted for NASA Langley Research Center. The objectives of the study were to (1) develop a GA SPIFR operational profile, (2) identify problems experienced by the GA SPIFR pilot, and (3) identify research tasks which have the potential for eliminating or reducing the severity of the problems. To obtain the information necessary to accomplish these objectives, a mail questionnaire survey of instrument rated pilots was conducted. Complete questionnaire data is reported in NASA CR-165805, "Statistical Summary: Study to Determine the IFR Operational Profile and Problems of the General Aviation Single Pilot'-Based upon the results of the GA SPIFR survey, this final report presents the general aviation IFR single pilot operational profile, illustrates selected data analysis, examples, identifies the problems which he is experiencing, and recommends further research.

Studies of ZVS soft switching of dual-active-bridge isolated bidirectional DC-DC converters

NASA Astrophysics Data System (ADS)

Xu, Fei; Zhao, Feng; Shi, Qibiao; Wen, Xuhui

2018-05-01

To operate dual-active-bridge isolated bidirectional dc- dc converter (DAB) at high efficiency, the two bridge switches must operate with Zero-Voltage-Switching (ZVS) over as wide an operating range as possible. This paper proposes a new perspective on realizing ZVS in dead-time. An exact theoretical analysis and mathematical mode is built to explain the process of ZVS switching in dead-time under Single Phase Shift (SPS) control strategy. In order to assure the two bridge switches operate on soft switching, every SPS switching point is analyzed. Generally, dead-time will be determined when the power electronic devices is selected. The key factor to realizing ZVS is the size of the end time of resonance comparing to dead-time. Through detailed analysis, it can obtain the conditions of all switches achieving ZVS turn-on and turn-off. Finally, simulation validates the theoretical analysis and some advice are given to realize the ZVS soft switching.

Operational modal analysis applied to the concert harp

NASA Astrophysics Data System (ADS)

Chomette, B.; Le Carrou, J.-L.

2015-05-01

Operational modal analysis (OMA) methods are useful to extract modal parameters of operating systems. These methods seem to be particularly interesting to investigate the modal basis of string instruments during operation to avoid certain disadvantages due to conventional methods. However, the excitation in the case of string instruments is not optimal for OMA due to the presence of damped harmonic components and low noise in the disturbance signal. Therefore, the present study investigates the least-square complex exponential (LSCE) and the modified least-square complex exponential methods in the case of a string instrument to identify modal parameters of the instrument when it is played. The efficiency of the approach is experimentally demonstrated on a concert harp excited by some of its strings and the two methods are compared to a conventional modal analysis. The results show that OMA allows us to identify modes particularly present in the instrument's response with a good estimation especially if they are close to the excitation frequency with the modified LSCE method.

The use of rifaximin in pre-operative period of patients with tumors of the gastrointestinal tract - a retrospective study (2013-2016).

PubMed

Moroz, Nina; Sitarz, Robert; Mruk, Andrzej; Bakalarz, Robert; Maciąg, Ewa; Litwiński, Jakub; Wierzbicki, Ryszard

2018-02-28

ntroduction: One of the most important goals of preparing a patient for elective gastrointestinal cancer surgery is prevention of postoperative complications. The literature gives many ways to prepare for surgery, but only a few suggests that pre-operative use of rifaximin provides benefits in the form of fewer perioperative complications and reduces the severity of pain during this period. O bjective: The presented project is a retrospective analysis of the effectiveness of rifaximin in the prevention of perioperative complications in patients treated in the Unit of General Surgery with the Orthopedic and Urology in the Hospital of the Ministry of the Interior and Administration in Lublin, and a review of international literature in this subject. A retrospective analysis of the results of pre-operative use of rifaximin was performed in 181 patients scheduled for rectal and colorectal cancer between 2013 and 2016 in the General Surgery Unit with the Orthopedic and Urology in the Hospital of the Ministry of Interior and Administration in Lublin. Patients undergoing urgent surgery were excluded from the study. Patients were divided into 2 groups. The first group of 139 patients - patients operated on for rectal and colorectal cancer in 2013 until 2015, in whom rifaximine was not used in the preoperative period. The second group is 42 patients, operated on in 2016, in which the rifaximin was used in the pre-operative period at a dose of 2x2 tablets (400 mg) per day, 12-hour interval, for 7 days before the planned operation. Additionally, a probiotic was administered for 7 days. Drugs were ordained at the Oncological Outpatient Clinic as part of the pre-hospitalization check. R esults: The use of rifaximin in the preoperative period in patients with colorectal cancer had an effect on shortening the time of post-operative hospitalization and reduced post-surgical pain in comparison with the control group. The analysis of the cynumber and intensity of surgical complications in both groups did not differ. C onclusions: Large studies on the influence of rifaximin on the development of colorectal cancer have not been published so far. Only single reports suggest that its use has a positive effect on the perioperative period of patients treated for colorectal cancer including rectum and our retrospective analysis confirms these observations.

New techniques for the analysis of manual control systems. [mathematical models of human operator behavior

NASA Technical Reports Server (NTRS)

Bekey, G. A.

1971-01-01

Studies are summarized on the application of advanced analytical and computational methods to the development of mathematical models of human controllers in multiaxis manual control systems. Specific accomplishments include the following: (1) The development of analytical and computer methods for the measurement of random parameters in linear models of human operators. (2) Discrete models of human operator behavior in a multiple display situation were developed. (3) Sensitivity techniques were developed which make possible the identification of unknown sampling intervals in linear systems. (4) The adaptive behavior of human operators following particular classes of vehicle failures was studied and a model structure proposed.

Applying AI tools to operational space environmental analysis

NASA Technical Reports Server (NTRS)

Krajnak, Mike; Jesse, Lisa; Mucks, John

1995-01-01

The U.S. Air Force and National Oceanic Atmospheric Agency (NOAA) space environmental operations centers are facing increasingly complex challenges meeting the needs of their growing user community. These centers provide current space environmental information and short term forecasts of geomagnetic activity. Recent advances in modeling and data access have provided sophisticated tools for making accurate and timely forecasts, but have introduced new problems associated with handling and analyzing large quantities of complex data. AI (Artificial Intelligence) techniques have been considered as potential solutions to some of these problems. Fielding AI systems has proven more difficult than expected, in part because of operational constraints. Using systems which have been demonstrated successfully in the operational environment will provide a basis for a useful data fusion and analysis capability. Our approach uses a general purpose AI system already in operational use within the military intelligence community, called the Temporal Analysis System (TAS). TAS is an operational suite of tools supporting data processing, data visualization, historical analysis, situation assessment and predictive analysis. TAS includes expert system tools to analyze incoming events for indications of particular situations and predicts future activity. The expert system operates on a knowledge base of temporal patterns encoded using a knowledge representation called Temporal Transition Models (TTM's) and an event database maintained by the other TAS tools. The system also includes a robust knowledge acquisition and maintenance tool for creating TTM's using a graphical specification language. The ability to manipulate TTM's in a graphical format gives non-computer specialists an intuitive way of accessing and editing the knowledge base. To support space environmental analyses, we used TAS's ability to define domain specific event analysis abstractions. The prototype system defines events covering reports of natural phenomena such as solar flares, bursts, geomagnetic storms, and five others pertinent to space environmental analysis. With our preliminary event definitions we experimented with TAS's support for temporal pattern analysis using X-ray flare and geomagnetic storm forecasts as case studies. We are currently working on a framework for integrating advanced graphics and space environmental models into this analytical environment.

Evaluation of median nerve T2 signal changes in patients with surgically treated carpal tunnel syndrome.

PubMed

Samanci, Yavuz; Karagöz, Yeşim; Yaman, Mehmet; Atçı, İbrahim Burak; Emre, Ufuk; Kılıçkesmez, Nuri Özgür; Çelik, Suat Erol

2016-11-01

To determine the accuracy of median nerve T2 evaluation and its relation with Boston Questionnaire (BQ) and nerve conduction studies (NCSs) in pre-operative and post-operative carpal tunnel syndrome (CTS) patients in comparison with healthy volunteers. Twenty-three CTS patients and 24 healthy volunteers underwent NCSs, median nerve T2 evaluation and self-administered BQ. Pre-operative and 1st year post-operative median nerve T2 values and cross-sectional areas (CSAs) were compared both within pre-operative and post-operative CTS groups, and with healthy volunteers. The relationship between MRI findings and BQ and NCSs was analyzed. The ROC curve analysis was used for determining the accuracy. The comparison of pre-operative and post-operative T2 values and CSAs revealed statistically significant improvements in the post-operative patient group (p<0.001 for all parameters). There were positive correlations between T2 values at all levels and BQ values, and positive and negative correlations were also found regarding T2 values and NCS findings in CTS patients. The receiver operating characteristic curve analysis for defined cut-off levels of median nerve T2 values in hands with severe CTS yielded excellent accuracy at all levels. However, this accuracy could not be demonstrated in hands with mild CTS. This study is the first to analyze T2 values in both pre-operative and post-operative CTS patients. The presence of increased T2 values in CTS patients compared to controls and excellent accuracy in hands with severe CTS indicates T2 signal changes related to CTS pathophysiology and possible utilization of T2 signal evaluation in hands with severe CTS. Copyright © 2016 Elsevier B.V. All rights reserved.

HUMeral shaft fractures: measuring recovery after operative versus non-operative treatment (HUMMER): a multicenter comparative observational study.

PubMed

Mahabier, Kiran C; Van Lieshout, Esther M M; Bolhuis, Hugo W; Bos, P Koen; Bronkhorst, Maarten Wga; Bruijninckx, Milko M M; De Haan, Jeroen; Deenik, Axel R; Dwars, Boudewijn J; Eversdijk, Martin G; Goslings, J Carel; Haverlag, Robert; Heetveld, Martin J; Kerver, Albert J H; Kolkman, Karel A; Leenhouts, Peter A; Meylaerts, Sven A G; Onstenk, Ron; Poeze, Martijn; Poolman, Rudolf W; Punt, Bas J; Roerdink, W Herbert; Roukema, Gert R; Sintenie, Jan Bernard; Soesman, Nicolaj M R; Tanka, Andras K F; Ten Holder, Edgar J T; Van der Elst, Maarten; Van der Heijden, Frank H W M; Van der Linden, Frits M; Van der Zwaal, Peer; Van Dijk, Jan P; Van Jonbergen, Hans-Peter W; Verleisdonk, Egbert J M M; Vroemen, Jos P A M; Waleboer, Marco; Wittich, Philippe; Zuidema, Wietse P; Polinder, Suzanne; Verhofstad, Michael H J; Den Hartog, Dennis

2014-02-11

Fractures of the humeral shaft are associated with a profound temporary (and in the elderly sometimes even permanent) impairment of independence and quality of life. These fractures can be treated operatively or non-operatively, but the optimal tailored treatment is an unresolved problem. As no high-quality comparative randomized or observational studies are available, a recent Cochrane review concluded there is no evidence of sufficient scientific quality available to inform the decision to operate or not. Since randomized controlled trials for this injury have shown feasibility issues, this study is designed to provide the best achievable evidence to answer this unresolved problem. The primary aim of this study is to evaluate functional recovery after operative versus non-operative treatment in adult patients who sustained a humeral shaft fracture. Secondary aims include the effect of treatment on pain, complications, generic health-related quality of life, time to resumption of activities of daily living and work, and cost-effectiveness. The main hypothesis is that operative treatment will result in faster recovery. The design of the study will be a multicenter prospective observational study of 400 patients who have sustained a humeral shaft fracture, AO type 12A or 12B. Treatment decision (i.e., operative or non-operative) will be left to the discretion of the treating surgeon. Critical elements of treatment will be registered and outcome will be monitored at regular intervals over the subsequent 12 months. The primary outcome measure is the Disabilities of the Arm, Shoulder, and Hand score. Secondary outcome measures are the Constant score, pain level at both sides, range of motion of the elbow and shoulder joint at both sides, radiographic healing, rate of complications and (secondary) interventions, health-related quality of life (Short-Form 36 and EuroQol-5D), time to resumption of ADL/work, and cost-effectiveness. Data will be analyzed using univariate and multivariable analyses (including mixed effects regression analysis). The cost-effectiveness analysis will be performed from a societal perspective. Successful completion of this trial will provide evidence on the effectiveness of operative versus non-operative treatment of patients with a humeral shaft fracture. The trial is registered at the Netherlands Trial Register (NTR3617).

Efficacy of clinical and radiological methods to identify second mesiobuccal canals in maxillary first molars.

PubMed

Abuabara, Allan; Baratto-Filho, Flares; Aguiar Anele, Juliana; Leonardi, Denise Piotto; Sousa-Neto, Manoel Damião

2013-01-01

The success of endodontic treatment depends on the identification of all root canals. Technological advances have facilitated this process as well as the assessment of internal anatomical variations. The aim of this study was to compare the efficacy of clinical and radiological methods in locating second mesiobuccal canals (MB2) in maxillary first molars. Fifty patients referred for analysis; access and clinical analysis; cone-beam endodontic treatment of their maxillary first molars were submitted to the following assessments: analysis; access and clinical analysis; cone-beam computed tomography (CBCT); post-CBCT clinical analysis; clinical analysis using an operating microscope; and clinical analysis after Start X ultrasonic inserts in teeth with negative results in all previous analyses. Periapical radiographic analysis revealed the presence of MB2 in four (8%) teeth, clinical analysis in 25 (50%), CBCT analysis in 27 (54%) and clinical analysis following CBCT and using an operating microscope in 27 (54%) and 29 (58%) teeth, respectively. The use of Start X ultrasonic inserts allowed one to detect two additional teeth with MB2 (62%). According to Vertucci's classification 48% of the mesiobuccal canals found were type I, 28% type II, 18% type IV and 6% type V. Statistical analysis showed no significant differences (p > 0.5) in the ability of CBCT to detect MB2 canals when compared with clinical assessment with or without an operating microscope. A significant difference (p < 0.001)was found only between periapical radiography and clinical/CBCT evaluations. Combined use of different methods increased the detection ofthe second canal in MB roots, but without statistical difference among CBCT, operating microscope, Start X and clinical analysis.

System Concept Study for a Cargo Data Interchange System (CARDIS)

DOT National Transportation Integrated Search

1975-04-01

The report presents the analysis of functional and operational requirements of CARDIS. From these requirements, system sizing estimates are derived. Three potential CARDIS concepts are introduced for consideration in subsequent analysis. Their charac...

Specialty hospitals emulating focused factories: a case study.

PubMed

Kumar, Sameer

2010-01-01

For 15 years general hospital managers faced new competition from for-profit specialty hospitals that operate on a "focused factory" model, which threaten to siphon-off the most profitable patients. This paper aims to discuss North American specialty hospitals and to review rising costs impact on general hospital operations. The focus is to discover whether specialty hospitals are more efficient than general hospitals; if so, how significant is the difference and also what can general hospitals do in light of the rising specialty hospitals. The case study involves stochastic frontier regression analysis using Cobb-Douglas and Translog cost functions to compare Minnesota general and specialty hospital efficiency. Analysis is based on data from 117 general and 19 specialty hospitals. The results suggest that specialty hospitals are significantly more efficient than general hospitals. Overall, general hospitals were found to be more than twice as inefficient compared with specialty hospitals in the sample. Some cost-cutting factors highlighted can be implemented to trim rising costs. The case study highlights some managerial levers that general hospital operational managers might use to control rising costs. This also helps them compete with specialty hospitals by reducing overheads and other major costs. The study is based on empirical modeling for an important healthcare operational challenge and provides additional in-depth information that has health policy implications. The analysis and findings enable healthcare managers to guide their institutions in a new direction during a time of change within the industry.

Factors associated with survival of epiploic foramen entrapment colic: a multicentre, international study.

PubMed

Archer, D C; Pinchbeck, G L; Proudman, C J

2011-08-01

Epiploic foramen entrapment (EFE) has been associated with reduced post operative survival compared to other types of colic but specific factors associated with reduced long-term survival of these cases have not been evaluated in a large number of horses using survival analysis. To describe post operative survival of EFE cases and to identify factors associated with long-term survival. A prospective, multicentre, international study was conducted using clinical data and long-term follow-up information for 126 horses diagnosed with EFE during exploratory laparotomy at 15 clinics in the UK, Ireland and USA. Descriptive data were generated and survival analysis performed to identify factors associated with reduced post operative survival. For the EFE cohort that recovered following anaesthesia, survival to hospital discharge was 78.5%. Survival to 1 and 2 years post operatively was 50.6 and 34.3%, respectively. The median survival time of EFE cases undergoing surgery was 397 days. Increased packed cell volume (PCV) and increased length of small intestine (SI) resected were significantly associated with increased likelihood of mortality when multivariable analysis of pre- and intraoperative variables were analysed. When all pre-, intra- and post operative variables were analysed separately, only horses that developed post operative ileus (POI) were shown to be at increased likelihood of mortality. Increased PCV, increased length of SI resected and POI are all associated with increased likelihood of mortality of EFE cases. This emphasises the importance of early diagnosis and treatment and the need for improved strategies in the management of POI in order to reduce post operative mortality in these cases. The present study provides evidence-based information to clinicians and owners of horses undergoing surgery for EFE about long-term survival. These results are applicable to university and large private clinics over a wide geographical area. © 2011 EVJ Ltd.

Cost comparison of transcatheter and operative closures of ostium secundum atrial septal defects

PubMed Central

O’Byrne, Michael L.; Gillespie, Matthew J.; Shinohara, Russell T.; Dori, Yoav; Rome, Jonathan J.; Glatz, Andrew C.

2015-01-01

Background Clinical outcomes for transcatheter and operative closures of atrial septal defects (ASDs) are similar. Economic cost for each method has not been well described. Methods A single-center retrospective cohort study of children and adults <30 years of age undergoing closure for single secundum ASD from January 1, 2007, to April 1, 2012, was performed to measure differences in inflation-adjusted cost of operative and transcatheter closures of ASD. A propensity score weight-adjusted multivariate regression model was used in an intention-to-treat analysis. Costs for reintervention and crossover admissions were included in primary analysis. Results A total of 244 subjects were included in the study (64% transcatheter and 36% operative), of which 2% (n = 5) were ≥18 years. Crossover rate from transcatheter to operative group was 3%. Risk of reintervention (P = .66) and 30-day mortality (P = .37) were not significantly different. In a multivariate model, adjusted cost of operative closure was 2012 US $60,992 versus 2012 US $55,841 for transcatheter closure (P < .001). Components of total cost favoring transcatheter closure were length of stay, medications, and follow-up radiologic and laboratory testing, overcoming higher costs of procedure and echocardiography. Professional costs did not differ. The rate of 30-day readmission was greater in the operative cohort, further increasing the cost advantage of transcatheter closure. Sensitivity analyses demonstrated that costs of follow-up visits influenced relative cost but that device closure remained favorable over a broad range of crossover and reintervention rates. Conclusion For single secundum ASD, cost comparison analysis favors transcatheter closure over the short term. The cost of follow-up regimens influences the cost advantage of transcatheter closure. PMID:25965721

Effect of facility on the operative costs of distal radius fractures.

PubMed

Mather, Richard C; Wysocki, Robert W; Mack Aldridge, J; Pietrobon, Ricardo; Nunley, James A

2011-07-01

The purpose of this study was to investigate whether ambulatory surgery centers can deliver lower-cost care and to identify sources of those cost savings. We performed a cost identification analysis of outpatient volar plating for closed distal radius fractures at a single academic medical center. Multiple costs and time measures were taken from an internal database of 130 consecutive patients and were compared by venue of treatment, either an inpatient facility or an ambulatory, stand-alone surgery facility. The relationships between total cost and operative time and multiple variables, including fracture severity, patient age, gender, comorbidities, use of bone graft, concurrent carpal tunnel release, and surgeon experience, were examined, using multivariate analysis and regression modeling to identify other cost drivers or explanatory variables. The mean operative cost was considerably greater at the inpatient facility ($7,640) than at the outpatient facility ($5,220). Cost drivers of this difference were anesthesia services, post-anesthesia care unit, and operating room costs. Total surgical time, nursing time, set-up, and operative times were 33%, 109%, 105%, and 35% longer, respectively, at the inpatient facility. There was no significant difference between facilities for the additional variables, and none of those variables independently affected cost or operative time. The only predictor of cost and time was facility type. This study supports the use of ambulatory stand-alone surgical facilities to achieve efficient resource utilization in the operative treatment of distal radius fractures. We also identified several specific costs and time measurements that differed between facilities, which can serve as potential targets for tertiary facilities to improve utilization. Economic and Decisional Analysis III. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Spaceliner Class Operability Gains Via Combined Airbreathing/ Rocket Propulsion: Summarizing an Operational Assessment of Highly Reusable Space Transports

NASA Technical Reports Server (NTRS)

Nix, Michael B.; Escher, William J. d.

1999-01-01

In discussing a new NASA initiative in advanced space transportation systems and technologies, the Director of the NASA Marshall Space Flight Center, Arthur G. Stephenson, noted that, "It would use new propulsion technology, air-breathing engine so you don't have to carry liquid oxygen, at least while your flying through the atmosphere. We are calling it Spaceliner 100 because it would be 100 times cheaper, costing $ 100 dollars a pound to orbit." While airbreathing propulsion is directly named, rocket propulsion is also implied by, "... while you are flying through the atmosphere." In-space final acceleration to orbital speed mandates rocket capabilities. Thus, in this informed view, Spaceliner 100 will be predicated on combined airbreathing/rocket propulsion, the technical subject of this paper. Interestingly, NASA's recently concluded Highly Reusable Space Transportation (HRST) study focused on the same affordability goal as that of the Spaceliner 100 initiative and reflected the decisive contribution of combined propulsion as a way of expanding operability and increasing the design robustness of future space transports, toward "aircraft like" capabilities. The HRST study built on the Access to Space Study and the Reusable Launch Vehicle (RLV) development activities to identify and characterize space transportation concepts, infrastructure and technologies that have the greatest potential for reducing delivery cost by another order of magnitude, from $1,000 to $100-$200 per pound for 20,000 lb. - 40.000 lb. payloads to low earth orbit (LEO). The HRST study investigated a number of near-term, far-term, and very far-term launch vehicle concepts including all-rocket single-stage-to-orbit (SSTO) concepts, two-stage-to-orbit (TSTO) concepts, concepts with launch assist, rocket-based combined cycle (RBCC) concepts, advanced expendable vehicles, and more far term ground-based laser powered launchers. The HRST study consisted of preliminary concept studies, assessments and analysis tool development for advanced space transportation systems, followed by end-to-end system concept definitions and trade analyses, specific system concept definition and analysis, specific key technology and topic analysis, system, operational and economics model development, analysis, and integrated assessments. The HRST Integration Task Force (HITF) was formed to synthesize study results in several specific topic areas and support the development of conclusions from the study: Systems Concepts Definitions, Technology Assessment, Operations Assessment, and Cost Assessment. This paper summarizes the work of the Operations Assessment Team: the six approaches used, the analytical tools and methodologies developed and employed, the issues and concerns, and the results of the assessment. The approaches were deliberately varied in measures of merit and procedure to compensate for the uncertainty inherent in operations data in this early phase of concept exploration. In general, rocket based combined cycle (RBCC) concepts appear to have significantly greater potential than all-rocket concepts for reducing operations costs.

Feasibility study of solid oxide fuel cell engines integrated with sprinter gas turbines: Modeling, design and control

NASA Astrophysics Data System (ADS)

Jia, Zhenzhong; Sun, Jing; Dobbs, Herb; King, Joel

2015-02-01

Conventional recuperating solid oxide fuel cell (SOFC)/gas turbine (GT) system suffers from its poor dynamic capability and load following performance. To meet the fast, safe and efficient load following requirements for mobile applications, a sprinter SOFC/GT system concept is proposed in this paper. In the proposed system, an SOFC stack operating at fairly constant temperature provides the baseline power with high efficiency while the fast dynamic capability of the GT-generator is fully explored for fast dynamic load following. System design and control studies have been conducted by using an SOFC/GT system model consisting of experimentally-verified component models. In particular, through analysis of the steady-state simulation results, an SOFC operation strategy is proposed to maintain fairly constant SOFC power (less than 2% power variation) and temperature (less than 2 K temperature variation) over the entire load range. A system design procedure well-suited to the proposed system has also been developed to help determining component sizes and the reference steady-state operation line. In addition, control analysis has been studied for both steady-state and transient operations. Simulation results suggest that the proposed system holds the promise to achieve fast and safe transient operations by taking full advantage of the fast dynamics of the GT-generator.

FINANCIAL ANALYSIS OF CURRENT OPERATIONS OF COLLEGES AND UNIVERSITIES.

ERIC Educational Resources Information Center

SWANSON, JOHN E.; AND OTHERS

TECHNIQUES FOR DEVELOPING FINANCIAL AND RELATED COST-EFFECTIVENESS DATA FOR PUBLIC AND PRIVATELY SUPPORTED AMERICAN COLLEGES AND UNIVERSITIES WERE STUDIED TO FORMULATE PRINCIPLES, PROCEDURES, AND STANDARDS FOR THE ACCUMULATION AND ANALYSES OF CURRENT OPERATING COSTS. AFTER SEPARATE ANALYSES OF INSTITUTIONAL PROCEDURES AND REPORTS, ANALYTIC UNITS…

Operational analysis of shared lane markings and green bike lanes on roadways with speeds greater than 35 mph.

DOT National Transportation Integrated Search

2014-01-01

This study analyzed the effectiveness of shared lane markings (sharrows), wide curb lanes, standard and buffered : bike lanes, and green bike lanes on improving operations of bicycle facilities. Three measures of effectiveness : were used in this stu...

Functional capacity following univentricular repair--midterm outcome.

PubMed

Sen, Supratim; Bandyopadhyay, Biswajit; Eriksson, Peter; Chattopadhyay, Amitabha

2012-01-01

Previous studies have seldom compared functional capacity in children following Fontan procedure alongside those with Glenn operation as destination therapy. We hypothesized that Fontan circulation enables better midterm submaximal exercise capacity as compared to Glenn physiology and evaluated this using the 6-minute walk test. Fifty-seven children aged 5-18 years with Glenn (44) or Fontan (13) operations were evaluated with standard 6-minute walk protocols. Baseline SpO(2) was significantly lower in Glenn patients younger than 10 years compared to Fontan counterparts and similar in the two groups in older children. Postexercise SpO(2) fell significantly in Glenn patients compared to the Fontan group. There was no statistically significant difference in baseline, postexercise, or postrecovery heart rates (HRs), or 6-minute walk distances in the two groups. Multiple regression analysis revealed lower resting HR, higher resting SpO(2) , and younger age at latest operation to be significant determinants of longer 6-minute walk distance. Multiple regression analysis also established that younger age at operation, higher resting SpO(2) , Fontan operation, lower resting HR, and lower postexercise HR were significant determinants of higher postexercise SpO(2) . Younger age at operation and exercise, lower resting HR and postexercise HR, higher resting SpO(2) and postexercise SpO(2) , and dominant ventricular morphology being left ventricular or indeterminate/mixed had significant association with better 6-minute work on multiple regression analysis. Lower resting HR had linear association with longer 6-minute walk distances in the Glenn patients. Compared to Glenn physiology, Fontan operation did not have better submaximal exercise capacity assessed by walk distance or work on multiple regression analysis. Lower resting HR, higher resting SpO(2) , and younger age at operation were factors uniformly associated with better submaximal exercise capacity. © 2012 Wiley Periodicals, Inc.

Examination of Factors that Influence the Operation Income and Expenditure Balance Difference Rate of 20 Educational Foundation Universities.

PubMed

Nakajima, Hisato; Yano, Kouya; Nagasawa, Kaoko; Katou, Satoka; Yokota, Kuninobu

2017-01-01

The objective of this study is to examine the factors that influence the operation income and expenditure balance ratio of school corporations running university hospitals by multiple regression analysis. 1. We conducted cluster analysis of the financial ratio and classified the school corporations into those running colleges and universities.2. We conducted multiple regression analysis using the operation income and expenditure balance ratio of the colleges as the variables and the Diagnosis Procedure Combination data as the explaining variables.3. The predictive expression was used for multiple regression analysis. 1. The school corporations were divided into those running universities (7), colleges (20) and others. The medical income ratio and the debt ratio were high and the student payment ratio was low in the colleges.2. The numbers of emergency care hospitalizations, operations, radiation therapies, and ambulance conveyances, and the complexity index had a positive influence on the operation income and expenditure balance ratio. On the other hand, the number of general anesthesia procedures, the cover rate index, and the emergency care index had a negative influence.3. The predictive expression was as follows.Operation income and expenditure balance ratio = 0.027 × number of emergency care hospitalizations + 0.005 × number of operations + 0.019 × number of radiation therapies + 0.007 × number of ambulance conveyances - 0.003 × number of general anesthesia procedures + 648.344 × complexity index - 5877.210 × cover rate index - 2746.415 × emergency care index - 38.647Conclusion: In colleges, the number of emergency care hospitalizations, the number of operations, the number of radiation therapies, and the number of ambulance conveyances and the complexity index were factors for gaining ordinary profit.

Ergonomic task analysis of ultrasound-guided femoral nerve block: a pilot study.

PubMed

Ajmal, Muhammad; Power, Susan; Smith, Tim; Shorten, George D

2011-02-01

To apply ergonomic task analysis to the performance of ultrasound-guided (US-guided) femoral nerve block (FNB) in an acute hospital setting. Pilot prospective observational study. Orthopedic operating room of a regional trauma hospital. 15 anesthesiologists of various levels of experience in US-guided FNB (estimated minimum experience < 10 procedures; maximum about 50 procedures, and from basic trainees to consultants); and 15 patients (5 men and 10 women), aged 77 ± 15 (mean ± SD yrs) years. MEASUREMENTS/OBSERVATIONS: A data capture "tool", which was modified from one previously developed for ergonomic study of spinal anesthesia, was studied. Patient, operator, and heterogeneous environmental factors related to ergonomic performance of US-guided FNB were identified. The observation period started immediately before commencement of positioning the patient and ended on completion of perineural injection. Data were acquired using direct observations, photography, and application of a questionnaire. The quality of ergonomic performance was generally suboptimal and varied greatly among operators. Eight (experience < 10 procedures) of 15 operators excessively rotated their head, neck, and/or back to visualize the image on the ultrasound machine. Eight operators (experience < 10 procedures) performed the procedure with excessive thoracolumbar flexion. Performance of US-guided FNB presents ergonomic challenges and was suboptimal during most of the procedures observed. Formal training in US-guided peripheral nerve blockade should include reference to ergonomic factors. Copyright © 2011 Elsevier Inc. All rights reserved.

A case study of packaging waste collection systems in Portugal - Part I: Performance and operation analysis.

PubMed

Martinho, Graça; Gomes, Ana; Santos, Pedro; Ramos, Mário; Cardoso, João; Silveira, Ana; Pires, Ana

2017-03-01

The need to increase packaging recycling rates has led to the study and analysis of recycling schemes from various perspectives, including technical, economic, social, and environmental. This paper is part one of a three-part study devoted to comparing two recyclable packaging waste collection systems operating in western Portugal: a mixed collection system, where curbside and drop-off collections are operated simultaneously (but where the curbside system was introduced after the drop-off system), and an exclusive drop-off system. This part of the study focuses on analyzing the operation and performance of the two waste collection systems. The mixed collection system is shown to yield higher material separation rates, higher recycling rates, and lower contamination rates compared with the exclusive drop-off system, a result of the curbside component in the former system. However, the operational efficiency of the curbside collection in the mixed system is lower than the drop-off collection in the mixed system and the exclusive drop-off system, mainly because of inefficiency of collection. A key recommendation is to ensure that the systems should be optimized in an attempt to improve performance. Optimization should be applied not only to logistical aspects but also to citizens' participation, which could be improved by conducting curbside collection awareness campaigns in the neighborhoods that have a mixed system. Copyright © 2017 Elsevier Ltd. All rights reserved.

A feasibility study for conducting unattended night-time operations at WMKO

NASA Astrophysics Data System (ADS)

Stomski, Paul J.; Gajadhar, Sarah; Dahm, Scott; Jordan, Carolyn; Nordin, Tom

2016-08-01

In 2015, W. M. Keck Observatory conducted a study of the feasibility of conducting nighttime operations on Maunakea without any staff on the mountain. The study was motivated by the possibility of long term operational costs savings as well as other expected benefits. The goals of the study were to understand the technical feasibility and risk as well as to provide labor and cost estimates for implementation. The results of the study would be used to inform a decision about whether or not to fund and initiate a formal project aimed at the development of this new unattended nighttime operating capability. In this paper we will describe the study process as well as a brief summary of the results including the identified viable design alternative, the risk analysis, and the scope of work. We will also share the decisions made as a result of the study and current status of related follow-on activity.

Influence evaluation of loading conditions during pressurized thermal shock transients based on thermal-hydraulics and structural analyses

NASA Astrophysics Data System (ADS)

Katsuyama, Jinya; Uno, Shumpei; Watanabe, Tadashi; Li, Yinsheng

2018-03-01

The thermal hydraulic (TH) behavior of coolant water is a key factor in the structural integrity assessments on reactor pressure vessels (RPVs) of pressurized water reactors (PWRs) under pressurized thermal shock (PTS) events, because the TH behavior may affect the loading conditions in the assessment. From the viewpoint of TH behavior, configuration of plant equipment and their dimensions, and operator action time considerably influence various parameters, such as the temperature and flow rate of coolant water and inner pressure. In this study, to investigate the influence of the operator action time on TH behavior during a PTS event, we developed an analysis model for a typical Japanese PWR plant, including the RPV and the main components of both primary and secondary systems, and performed TH analyses by using a system analysis code called RELAP5. We applied two different operator action times based on the Japanese and the United States (US) rules: Operators may act after 10 min (Japanese rules) and 30 min (the US rules) after the occurrence of PTS events. Based on the results of TH analysis with different operator action times, we also performed structural analyses for evaluating thermal-stress distributions in the RPV during PTS events as loading conditions in the structural integrity assessment. From the analysis results, it was clarified that differences in operator action times significantly affect TH behavior and loading conditions, as the Japanese rule may lead to lower stresses than that under the US rule because an earlier operator action caused lower pressure in the RPV.

Operation Team Spirit: Program Review and Analysis

DTIC Science & Technology

2009-06-01

research was strictly qualitative in nature. The specific method being used was exploratory case study analysis... study , method is used for the specific acts of conducting research , while methodology refers to the qualitative nature of research performed. While...the researcher . According to Leedy and Ormrod (2005), some of the types of methods and their respective purposes include: • Case study :

Receiver operating characteristic (ROC) curves: review of methods with applications in diagnostic medicine

NASA Astrophysics Data System (ADS)

Obuchowski, Nancy A.; Bullen, Jennifer A.

2018-04-01

Receiver operating characteristic (ROC) analysis is a tool used to describe the discrimination accuracy of a diagnostic test or prediction model. While sensitivity and specificity are the basic metrics of accuracy, they have many limitations when characterizing test accuracy, particularly when comparing the accuracies of competing tests. In this article we review the basic study design features of ROC studies, illustrate sample size calculations, present statistical methods for measuring and comparing accuracy, and highlight commonly used ROC software. We include descriptions of multi-reader ROC study design and analysis, address frequently seen problems of verification and location bias, discuss clustered data, and provide strategies for testing endpoints in ROC studies. The methods are illustrated with a study of transmission ultrasound for diagnosing breast lesions.

An Exploratory Analysis of Projected Navy Officer Inventory Strength Using Data Farming

DTIC Science & Technology

2016-09-01

model’s run-time. 3. Base Case In addition to the experimental design, this study includes a base case scenario to serve as a baseline for comparison...47 3. SWO Operating Strength Deviation-Base Case One objective of this study is to determine the risk in operating strength deviation presented by...ANSWERS TO RESEARCH QUESTIONS ................................... 71  B.  RECOMMENDATIONS FOR FUTURE STUDIES ......................... 73  1.  Continuous

Ground Operations Aerospace Language (GOAL). Volume 1: Study overview

NASA Technical Reports Server (NTRS)

1973-01-01

A series of NASA and Contractor studies sponsored by NASA/KSC resulted in a specification for the Ground Operations Aerospace Language (GOAL). The Cape Kennedy Facility of the IBM Corporation was given the responsibility, under existing contracts, to perform an analysis of the Language Specification, to design and develop a GOAL Compiler, to provide a specification for a data bank, to design and develop an interpretive code translator, and to perform associated application studies.

Smoke on the water-Oral fluid analysis at sea.

PubMed

Griffiths, Andrew; Leonars, Richard; Hadley, Lenore; Stephenson, Mark; Teale, Richard

2017-09-01

This study outlines the operational challenges and findings of an illicit drug oral fluid testing program carried out on the skippers (those in charge) of water vessels in Queensland, Australia. Between 2010 and 2016, 953 tests of skippers were conducted on water (waterside) for three proscribed illicit drugs; delta-9-tetrahydrocannabinol (THC), methylamphetamine (MA) and 3,4-methylendioxymethylamphetamine (MDMA). 126 (13%) of the skippers tested returned an on-site positive during waterside testing, 125 were confirmed positive for one or more illicit drug by subsequent laboratory analysis, whilst one skipper did not provide an oral fluid sample for confirmatory analysis. The skippers were entirely male (100%) with an average age of 39 years (range 17-59). THC was by far the most common drug detected (91%); MA was detected in 22% of skippers and a combination or THC and MA in 14% of specimens. MDMA was identified only once during the study, this being in combination with THC. As a single waterside operation can take more than a week, operational pre-planning becomes essential. Aspects of the operation such as, weather, shift times, food, testing consumables, sleeping quarters, hygiene, liaison between different agencies and multiple other factors need to be taken into account prior to commencement. A waterside operation must be mobile and, in Queensland at least, able to cover a large area of water. There is also a much lower volume of vessels likely to be encountered at sea compared to a roadside operation targeting motor vehicles. Copyright © 2017 Elsevier B.V. All rights reserved.

Prognostic Analysis System and Methods of Operation

NASA Technical Reports Server (NTRS)

MacKey, Ryan M. E. (Inventor); Sneddon, Robert (Inventor)

2014-01-01

A prognostic analysis system and methods of operating the system are provided. In particular, a prognostic analysis system for the analysis of physical system health applicable to mechanical, electrical, chemical and optical systems and methods of operating the system are described herein.

Space shuttle/food system study. Volume 2, Appendix A: Active heating system-screening analysis. Appendix B: Reconstituted food heating techniques analysis

NASA Technical Reports Server (NTRS)

1974-01-01

Technical data are presented which were used to evaluate active heating methods to be incorporated into the space shuttle food system design, and also to evaluate the relative merits and penalties associated with various approaches to the heating of rehydrated food during space flight. Equipment heating candidates were subject to a preliminary screening performed by a selection rationale process which considered the following parameters; (1) gravitational effect; (2) safety; (3) operability; (4) system compatibility; (5) serviceability; (6) crew acceptability; (7) crew time; (8) development risk; and (9) operating cost. A hot air oven, electrically heated food tray, and microwave oven were selected for further consideration and analysis. Passive, semi-active, and active food preparation approaches were also studied in an effort to determine the optimum method for heating rehydrated food. Potential complexity, cost, vehicle impact penalties, and palatability were considered in the analysis. A summary of the study results is provided along with cost estimates for each of the potential sytems

Geomechanical Assessments of Simultaneous Operation in the Case of Transition from Open Pit to Underground Mine in Vietnam

NASA Astrophysics Data System (ADS)

Niedbalski, Zbigniew; Nguyen, Phu Minh Vuong; Widzyk-Capehart, Eleonora

2018-03-01

Nowadays, for a number of reasons, many open pit mines are considering a transition from Open Pit (OP) to Underground (UG) to remain competitive. In OP-UG transition, UG operation is operated simultaneously with the OP operation for a certain period of time. Guidelines for the simultaneous operation of OP and UG are very difficult to establish, as there are very few case studies available. Yet, because of the OP-UG interactions; the operation has a higher safety, technical and management requirements than the OP or UG methods when considered separately. In Vietnam, Cao Son is one of many OP mines, which decided to change the operational system from OP to UG. Simultaneous operation started in 2015 and will be conducted until 2030 when the OP mine Cao Son ends its mining activities. In this paper, selected geomechanical considerations of the simultaneous operation are presented. A number of numerical modelling calculations using finitedifference software with code FLAC were carried out for calibration process, slope stability analysis and the OP-UG interaction analysis for the Cao Son - Khe Cham II-IV mine. Based on the results obtained from numerical modelling, the geomechanical assessments of simultaneous operation Cao Son - Khe Cham II-IV are discussed in this paper.

On orthogonal expansions of the space of vector functions which are square-summable over a given domain and the vector analysis operators

NASA Technical Reports Server (NTRS)

Bykhovskiy, E. B.; Smirnov, N. V.

1983-01-01

The Hilbert space L2(omega) of vector functions is studied. A breakdown of L2(omega) into orthogonal subspaces is discussed and the properties of the operators for projection onto these subspaces are investigated from the standpoint of preserving the differential properties of the vectors being projected. Finally, the properties of the operators are examined.

A Technology Analysis to Support Acquisition of UAVs for Gulf Coalition Forces Operations

DTIC Science & Technology

2017-06-01

their selection of the most suitable and cost-effective unmanned aerial vehicles to support detection operations. This study uses Map Aware Non ...being detected by Gulf Coalition Forces and improved time to detect them, support the use of UAVs in detection missions. Computer experimentations and...aerial vehicles to support detection operations. We use Map Aware Non - Uniform Automata, an agent-based simulation software platform, for the

Orbital operations study. Appendix A: Interactivity analysis

NASA Technical Reports Server (NTRS)

1972-01-01

Supplemental analyses conducted to verify that safe, feasible, design concepts exist for accomplishing the attendant interface activities of the orbital operations mission are presented. The data are primarily concerned with functions and concepts common to more than one of the interfacing activities or elements. Specific consideration is given to state vector update, payload deployment, communications links, jet plume impingement, attached element operations, docking and structural interface assessment, and propellant transfer.

Statistical analysis of the effect of temperature and inlet humidities on the parameters of a semiempirical model of the internal resistance of a polymer electrolyte membrane fuel cell

NASA Astrophysics Data System (ADS)

Giner-Sanz, J. J.; Ortega, E. M.; Pérez-Herranz, V.

2018-03-01

The internal resistance of a PEM fuel cell depends on the operation conditions and on the current delivered by the cell. This work's goal is to obtain a semiempirical model able to reproduce the effect of the operation current on the internal resistance of an individual cell of a commercial PEM fuel cell stack; and to perform a statistical analysis in order to study the effect of the operation temperature and the inlet humidities on the parameters of the model. First, the internal resistance of the individual fuel cell operating in different operation conditions was experimentally measured for different DC currents, using the high frequency intercept of the impedance spectra. Then, a semiempirical model based on Springer and co-workers' model was proposed. This model is able to successfully reproduce the experimental trends. Subsequently, the curves of resistance versus DC current obtained for different operation conditions were fitted to the semiempirical model, and an analysis of variance (ANOVA) was performed in order to determine which factors have a statistically significant effect on each model parameter. Finally, a response surface method was applied in order to obtain a regression model.

Alternatives for the Training of Skilled Industrial Labor in Sao Paulo, Brazil. Program of Studies in Non-Formal Education, Supplementary Series. Paper No. 1.

ERIC Educational Resources Information Center

Lukomski, Michael

The study deals with the development of skilled industrial manpower in Sao Paulo, Brazil, and with the Federal government's SENAI (Service Nacional de Aprendizagem Industrial) industrial apprenticeship and trainign program. An analysis of six variables among lathe setter-operators showed that: present work situations among the operators varied…

Generic extravehicular (EVA) and telerobot task primitives for analysis, design, and integration. Version 1.0: Reference compilation for the EVA and telerobotics communities

NASA Technical Reports Server (NTRS)

Smith, Jeffrey H.; Drews, Michael

1990-01-01

The results are described of an effort to establish commonality and standardization of generic crew extravehicular (crew-EVA) and telerobotic task analysis primitives used for the study of spaceborne operations. Although direct crew-EVA plans are the most visible output of spaceborne operations, significant ongoing efforts by a wide variety of projects and organizations also require tools for estimation of crew-EVA and telerobotic times. Task analysis tools provide estimates for input to technical and cost tradeoff studies. A workshop was convened to identify the issues and needs to establish a common language and syntax for task analysis primitives. In addition, the importance of such a syntax was shown to have precedence over the level to which such a syntax is applied. The syntax, lists of crew-EVA and telerobotic primitives, and the data base in diskette form are presented.

Sensitivity to imputation models and assumptions in receiver operating characteristic analysis with incomplete data

PubMed Central

Karakaya, Jale; Karabulut, Erdem; Yucel, Recai M.

2015-01-01

Modern statistical methods using incomplete data have been increasingly applied in a wide variety of substantive problems. Similarly, receiver operating characteristic (ROC) analysis, a method used in evaluating diagnostic tests or biomarkers in medical research, has also been increasingly popular problem in both its development and application. While missing-data methods have been applied in ROC analysis, the impact of model mis-specification and/or assumptions (e.g. missing at random) underlying the missing data has not been thoroughly studied. In this work, we study the performance of multiple imputation (MI) inference in ROC analysis. Particularly, we investigate parametric and non-parametric techniques for MI inference under common missingness mechanisms. Depending on the coherency of the imputation model with the underlying data generation mechanism, our results show that MI generally leads to well-calibrated inferences under ignorable missingness mechanisms. PMID:26379316

Organizational Constraints and Goal Setting

ERIC Educational Resources Information Center

Putney, Frederick B.; Wotman, Stephen

1978-01-01

Management modeling techniques are applied to setting operational and capital goals using cost analysis techniques in this case study at the Columbia University School of Dental and Oral Surgery. The model was created as a planning tool used in developing a financially feasible operating plan and a 100 percent physical renewal plan. (LBH)

The Command & Control of Aggregated Marine Expeditionary Units. Is Anyone Available Today?

DTIC Science & Technology

2013-04-11

Operations. 24 April 2012. https://ehqmc.usmc.mil/org/ ppo /pl/pln. 2. Personal correspondence or phone interviews with each command listed...and Operations. 24 April 2012. https://ehqmc.usmc.mil/org/ ppo /pl/pln. Stover 53 Congressional Budget Office. A CBO Study: An Analysis of the

TRAC FY15 Research Planning and Elicitation

DTIC Science & Technology

2014-09-30

Wargaming and Simulation Directorate . . . . . . . . . . . . . C-2 Table C–7. FLVN-Operations Directorate . . . . . . . . . . . . . . . . . . . . . . C...Studies and Analysis III Directorate . . . . . . . . . . . . . . C-4 Table C–14.WSMR - Modeling and Simulation Directorate...Directorate - Mr. Decker • Wargaming and Simulation Directorate - Mr. Johnson • Operations Directorate - Ms. Fratzel • Scenarios and Data Directorate - Mr

The prognostic value of pre-operative and post-operative B-type natriuretic peptides in patients undergoing noncardiac surgery: B-type natriuretic peptide and N-terminal fragment of pro-B-type natriuretic peptide: a systematic review and individual patient data meta-analysis.

PubMed

Rodseth, Reitze N; Biccard, Bruce M; Le Manach, Yannick; Sessler, Daniel I; Lurati Buse, Giovana A; Thabane, Lehana; Schutt, Robert C; Bolliger, Daniel; Cagini, Lucio; Cardinale, Daniela; Chong, Carol P W; Chu, Rong; Cnotliwy, Miłosław; Di Somma, Salvatore; Fahrner, René; Lim, Wen Kwang; Mahla, Elisabeth; Manikandan, Ramaswamy; Puma, Francesco; Pyun, Wook B; Radović, Milan; Rajagopalan, Sriram; Suttie, Stuart; Vanniyasingam, Thuvaraha; van Gaal, William J; Waliszek, Marek; Devereaux, P J

2014-01-21

The objective of this study was to determine whether measuring post-operative B-type natriuretic peptides (NPs) (i.e., B-type natriuretic peptide [BNP] and N-terminal fragment of proBNP [NT-proBNP]) enhances risk stratification in adult patients undergoing noncardiac surgery, in whom a pre-operative NP has been measured. Pre-operative NP concentrations are powerful independent predictors of perioperative cardiovascular complications, but recent studies have reported that elevated post-operative NP concentrations are independently associated with these complications. It is not clear whether there is value in measuring post-operative NP when a pre-operative measurement has been done. We conducted a systematic review and individual patient data meta-analysis to determine whether the addition of post-operative NP levels enhanced the prediction of the composite of death and nonfatal myocardial infarction at 30 and ≥180 days after surgery. Eighteen eligible studies provided individual patient data (n = 2,179). Adding post-operative NP to a risk prediction model containing pre-operative NP improved model fit and risk classification at both 30 days (corrected quasi-likelihood under the independence model criterion: 1,280 to 1,204; net reclassification index: 20%; p < 0.001) and ≥180 days (corrected quasi-likelihood under the independence model criterion: 1,320 to 1,300; net reclassification index: 11%; p = 0.003). Elevated post-operative NP was the strongest independent predictor of the primary outcome at 30 days (odds ratio: 3.7; 95% confidence interval: 2.2 to 6.2; p < 0.001) and ≥180 days (odds ratio: 2.2; 95% confidence interval: 1.9 to 2.7; p < 0.001) after surgery. Additional post-operative NP measurement enhanced risk stratification for the composite outcomes of death or nonfatal myocardial infarction at 30 days and ≥180 days after noncardiac surgery compared with a pre-operative NP measurement alone. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Primary vs Conversion Total Hip Arthroplasty: A Cost Analysis

PubMed Central

Chin, Garwin; Wright, David J.; Snir, Nimrod; Schwarzkopf, Ran

2018-01-01

Introduction Increasing hip fracture incidence in the United States is leading to higher occurrences of conversion total hip arthroplasty (THA) for failed surgical treatment of the hip. In spite of studies showing higher complication rates in conversion THA, the Centers for Medicare and Medicaid services currently bundles conversion and primary THA under the same diagnosis-related group. We examined the cost of treatment of conversion THA compared with primary THA. Our hypothesis is that conversion THA will have higher cost and resource use than primary THA. Methods Fifty-one consecutive conversion THA patients (Current Procedure Terminology code 27132) and 105 matched primary THA patients (Current Procedure Terminology code 27130) were included in this study. The natural log-transformed costs for conversion and primary THA were compared using regression analysis. Age, gender, body mass index, American Society of Anesthesiologist, Charlson comorbidity score, and smoker status were controlled in the analysis. Conversion THA subgroups formed based on etiology were compared using analysis of variance analysis. Results Conversion and primary THAs were determined to be significantly different (P < .05) and greater in the following costs: hospital operating direct cost (29.2% greater), hospital operating total cost (28.8% greater), direct hospital cost (24.7% greater), and total hospital cost (26.4% greater). Conclusions Based on greater hospital operating direct cost, hospital operating total cost, direct hospital cost, and total hospital cost, conversion THA has significantly greater cost and resource use than primary THA. In order to prevent disincentives for treating these complex surgical patients, reclassification of conversion THA is needed, as they do not fit together with primary THA. PMID:26387923

Laparoscopic versus robotic-assisted Roux-en-Y gastric bypass: a retrospective, single-center study of early perioperative outcomes at a community hospital.

PubMed

Ahmad, Arif; Carleton, Jared D; Ahmad, Zoha F; Agarwala, Ashish

2016-09-01

The purpose of this study was to compare the operative and early perioperative outcomes of laparoscopic versus robotic-assisted Roux-en-Y gastric bypass procedures performed in a community hospital setting. The study was a chart review and analysis of the early perioperative outcomes of a total of 345 Roux-en-Y gastric bypass procedures performed by a single surgeon in a community hospital setting from January 2011 to October 2014. Of these, 173 procedures were performed laparoscopically and 172 were performed with robotic assistance utilizing the daVinci(®) surgical platform. Factors such as baseline patient characteristics, operative time, estimated blood loss (EBL), conversions to open procedure, complication rates, adverse events, length of stay (LOS), and return to the operating room for the two groups were retrospectively analyzed from a prospectively maintained database. Student's t test with unequal variances was used for statistical analysis, and a p value <0.05 was used for significance. There were no statistically significant differences in complication rates, EBL, or LOS between the two groups. There was a significant difference between the total operative times (135.30 ± 37.60 min for the laparoscopic procedure versus 154.84 ± 38.44 min for the robotic procedure, p < 0.05). There were no adverse intraoperative events, conversions to open procedures, leaks, strictures, returns to the operating room within 30 days, or mortalities in either group. Our study, which is the first of its kind to analyze the operative and early perioperative outcomes between laparoscopic and robotic-assisted Roux-en-Y gastric bypass procedures in the US community hospital setting, indicates that both are comparable in terms of safety, efficacy, and operative and early perioperative outcomes.

Six sigma tools in integrating internal operations of a retail pharmacy: a case study.

PubMed

Kumar, Sameer; Kwong, Anthony M

2011-01-01

This study was initiated to integrate information and enterprise-wide healthcare delivery system issues specifically within an inpatient retail pharmacy operation in a U.S. community hospital. Six Sigma tools were used to examine the effects to an inpatient retail pharmacy service process. Some of the tools used include service blueprints, cause-effect diagram, gap analysis derived from customer and employee surveys, mistake proofing was applied in various business situations and results were analyzed to identify and propose process improvements and integration. The research indicates that the Six Sigma tools in this discussion are very applicable and quite effective in helping to streamline and integrate the pharmacy process flow. Additionally, gap analysis derived from two different surveys was used to estimate the primary areas of focus to increase customer and employee satisfaction. The results of this analysis were useful in initiating discussions of how to effectively narrow these service gaps. This retail pharmaceutical service study serves as a framework for the process that should occur for successful process improvement tool evaluation and implementation. Pharmaceutical Service operations in the U.S. that use this integration framework must tailor it to their individual situations to maximize their chances for success.

Study on Network Error Analysis and Locating based on Integrated Information Decision System

NASA Astrophysics Data System (ADS)

Yang, F.; Dong, Z. H.

2017-10-01

Integrated information decision system (IIDS) integrates multiple sub-system developed by many facilities, including almost hundred kinds of software, which provides with various services, such as email, short messages, drawing and sharing. Because the under-layer protocols are different, user standards are not unified, many errors are occurred during the stages of setup, configuration, and operation, which seriously affect the usage. Because the errors are various, which may be happened in different operation phases, stages, TCP/IP communication protocol layers, sub-system software, it is necessary to design a network error analysis and locating tool for IIDS to solve the above problems. This paper studies on network error analysis and locating based on IIDS, which provides strong theory and technology supports for the running and communicating of IIDS.

Performance of ITER as a burning plasma experiment

NASA Astrophysics Data System (ADS)

Shimada, M.; Mukhovatov, V.; Federici, G.; Gribov, Y.; Kukushkin, A.; Murakami, Y.; Polevoi, A.; Pustovitov, V.; Sengoku, S.; Sugihara, M.

2004-02-01

Recent performance analysis has improved confidence in achieving Q (= fusion power/auxiliary heating power)geq 10 in inductive operation in ITER. Performance analysis based on empirical scalings shows the feasibility of achieving Q geq 10 in inductive operation, particularly with improved modelling of helium exhaust. Analysis has also indicated the possibility that ITER can potentially demonstrate Q ~ 50, enabling studies of self-heated plasmas. Theory-based core modelling indicates the need for a high pedestal temperature (3.2-5.3 keV) to achieve Q geq 10, which is in the range of projections with presently available pedestal scalings. Pellet injection from the high-field side would be useful in enhancing Q and reducing edge localized mode (ELM) heat load in high plasma current operation. If the ELM heat load is not acceptable, it could be made tolerable by further tilting the target plate. Steady state operation scenarios at Q = 5 have been developed with modest requirements on confinement improvement and beta (HH98(y,2) geq 1.3 and bgrN geq 2.6). Stabilization of the resistive wall modes (RWMs), required in such regimes, is feasible with the present saddle coils and power supplies with double-wall structures taken into account. Recent analysis shows a potential of high power steady state operation with a fusion power of 0.7 GW at Q ~ 8. Achievement of the required bgrN ~ 3.6 by RWM stabilization is a possibility. Further analysis is also needed on reduction of the divertor target heat load.

OMA analysis of a launcher under operational conditions with time-varying properties

NASA Astrophysics Data System (ADS)

Eugeni, M.; Coppotelli, G.; Mastroddi, F.; Gaudenzi, P.; Muller, S.; Troclet, B.

2018-05-01

The objective of this paper is the investigation of the capability of operational modal analysis approaches to deal with time-varying system in the low-frequency domain. Specifically, the problem of the identification of the dynamic properties of a launch vehicle, working under actual operative conditions, is studied. Two OMA methods are considered: the frequency-domain decomposition and the Hilbert transform method. It is demonstrated that both OMA approaches allow the time-tracking of modal parameters, namely, natural frequencies, damping ratios, and mode shapes, from the response accelerations only recorded during actual flight tests of a launcher characterized by a large mass variation due to fuel burning typical of the first phase of the flight.

Analysis of beam loss induced abort kicker instability

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

Zhang W.; Sandberg, J.; Ahrens, L.

2012-05-20

Through more than a decade of operation, we have noticed the phenomena of beam loss induced kicker instability in the RHIC beam abort systems. In this study, we analyze the short term beam loss before abort kicker pre-fire events and operation conditions before capacitor failures. Beam loss has caused capacitor failures and elevated radiation level concentrated at failed end of capacitor has been observed. We are interested in beam loss induced radiation and heat dissipation in large oil filled capacitors and beam triggered thyratron conduction. We hope the analysis result would lead to better protection of the abort systems andmore » improved stability of the RHIC operation.« less

Cleared for the visual approach: Human factor problems in air carrier operations

NASA Technical Reports Server (NTRS)

Monan, W. P.

1983-01-01

The study described herein, a set of 353 ASRS reports of unique aviation occurrences significantly involving visual approaches was examined to identify hazards and pitfalls embedded in the visual approach procedure and to consider operational practices that might help avoid future mishaps. Analysis of the report set identified nine aspects of the visual approach procedure that appeared to be predisposing conditions for inducing or exacerbating the effects of operational errors by flight crew members or controllers. Predisposing conditions, errors, and operational consequences of the errors are discussed. In a summary, operational policies that might mitigate the problems are examined.

Comparing the High School English Curriculum in Turkey through Multi-Analysis

ERIC Educational Resources Information Center

Batdi, Veli

2017-01-01

This study aimed to compare the High School English Curriculum (HSEC) in accordance with Stufflebeam's context, input, process and product (CIPP) model through multi-analysis. The research includes both quantitative and qualitative aspects. A descriptive analysis was operated through Rasch Measurement Model; SPSS program for the quantitative…

Application of Spatial Neural Network Model for Optimal Operation of Urban Drainage System

NASA Astrophysics Data System (ADS)

KIM, B. J.; Lee, J. Y.; KIM, H. I.; Son, A. L.; Han, K. Y.

2017-12-01

The significance of real-time operation of drainage pump and warning system for inundation becomes recently increased in order to coping with runoff by high intensity precipitation such as localized heavy rain that frequently and suddenly happen. However existing operation of drainage pump station has been made a decision according to opinion of manager based on stage because of not expecting exact time that peak discharge occur in pump station. Therefore the scale of pump station has been excessively estimated. Although it is necessary to perform quick and accurate inundation in analysis downtown area due to huge property damage from flood and typhoon, previous studies contained risk deducting incorrect result that differs from actual result owing to the diffusion aspect of flow by effect on building and road. The purpose of this study is to develop the data driven model for the real-time operation of drainage pump station and two-dimensional inundation analysis that are improved the problems of the existing hydrology and hydrological model. Neuro-Fuzzy system for real time prediction about stage was developed by estimating the type and number of membership function. Based on forecasting stage, it was decided when pump machine begin to work and how much water scoop up by using penalizing genetic algorithm. It is practicable to forecast stage, optimize pump operation and simulate inundation analysis in real time through the methodologies suggested in this study. This study can greatly contribute to the establishment of disaster information map that prevent and mitigate inundation in urban drainage area. The applicability of the development model for the five drainage pump stations in the Mapo drainage area was verified. It is considered to be able to effectively manage urban drainage facilities in the development of these operating rules. Keywords : Urban flooding; Geo-ANFIS method; Optimal operation; Drainage system; AcknowlegementThis research was supported by a grant (17AWMP-B079625-04) from Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

Zambia : long-term generation expansion study - executive summary.

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

Conzelmann, G.; Koritarov, V.; Buehring, W.

2008-02-28

The objective of this study is to analyze possible long-term development options of the Zambian electric power system in the period up to 2015. The analysis involved the hydro operations studies of the Zambezi river basin and the systems planning studies for the least-cost generation expansion planning. Two well-known and widely accepted computer models were used in the analysis: PC-VALORAGUA model for the hydro operations and optimization studies and the WASP-III Plus model for the optimization of long-term system development. The WASP-III Plus model is a part of the Argonne National Laboratory's Energy and Power Evaluation Model (ENPEP). The analysismore » was conducted in close collaboration with the Zambia Electricity Supply Corporation (ZESCO). On the initiative from The World Bank, the sponsor of the study, ZESCO formed a team of experts that participated in the analysis and were trained in the use of computer models. Both models were transferred to ZESCO free of charge and installed on several computers in the ZESCO corporate offices in Lusaka. In September-October 1995, two members of the ZESCO National Team participated in a 4-week training course at Argonne National Laboratory near Chicago, U.S.A., focusing on the long-term system expansion planning using the WASP and VALORAGUA models. The hydropower operations studies were performed for the whole Zambezi river basin, including the full installation of the Kariba power station, and the Cahora Bassa hydro power station in Mozambique. The analysis also included possible future projects such as Itezhi-Tezhi, Kafue Gorge Lower, and Batoka Gorge power stations. As hydropower operations studies served to determine the operational characteristics of the existing and future hydro power plants, it was necessary to simulate the whole Zambezi river basin in order to take into account all interactions and mutual influences between the hydro power plants. In addition, it allowed for the optimization of reservoir management and optimization of hydro cascades, resulting in the better utilization of available hydro potential. Numerous analyses were performed for different stages of system development. These include system configurations that correspond to years 1997, 2001, 2015 and 2020. Additional simulations were performed in order to determine the operational parameters of the three existing hydro power stations Victoria Falls, Kariba, and Kafue Gorge Upper, that correspond to the situation before and after their rehabilitation. The rehabilitation works for these three major power stations, that would bring their operational parameters and availability back to the design level, are planned to be carried out in the period until 2000. The main results of the hydro operations studies are presented in Table ES-1. These results correspond to VALORAGUA simulations of system configurations in the years 2001 and 2015. The minimum, average, and maximum electricity generation is based on the simulation of monthly water inflows that correspond to the chronological series of unregulated water inflows at each hydro profile in the period from April 1961 to March 1990. The recommended hydrology dataset provided in the Hydrology Report of the SADC Energy Project AAA 3.8 was used for this study.« less

Augmented reality user interface for mobile ground robots with manipulator arms

NASA Astrophysics Data System (ADS)

Vozar, Steven; Tilbury, Dawn M.

2011-01-01

Augmented Reality (AR) is a technology in which real-world visual data is combined with an overlay of computer graphics, enhancing the original feed. AR is an attractive tool for teleoperated UGV UIs as it can improve communication between robots and users via an intuitive spatial and visual dialogue, thereby increasing operator situational awareness. The successful operation of UGVs often relies upon both chassis navigation and manipulator arm control, and since existing literature usually focuses on one task or the other, there is a gap in mobile robot UIs that take advantage of AR for both applications. This work describes the development and analysis of an AR UI system for a UGV with an attached manipulator arm. The system supplements a video feed shown to an operator with information about geometric relationships within the robot task space to improve the operator's situational awareness. Previous studies on AR systems and preliminary analyses indicate that such an implementation of AR for a mobile robot with a manipulator arm is anticipated to improve operator performance. A full user-study can determine if this hypothesis is supported by performing an analysis of variance on common test metrics associated with UGV teleoperation.

New approach for reduction of diesel consumption by comparing different mining haulage configurations.

PubMed

Rodovalho, Edmo da Cunha; Lima, Hernani Mota; de Tomi, Giorgio

2016-05-01

The mining operations of loading and haulage have an energy source that is highly dependent on fossil fuels. In mining companies that select trucks for haulage, this input is the main component of mining costs. How can the impact of the operational aspects on the diesel consumption of haulage operations in surface mines be assessed? There are many studies relating the consumption of fuel trucks to several variables, but a methodology that prioritizes higher-impact variables under each specific condition is not available. Generic models may not apply to all operational settings presented in the mining industry. This study aims to create a method of analysis, identification, and prioritization of variables related to fuel consumption of haul trucks in open pit mines. For this purpose, statistical analysis techniques and mathematical modelling tools using multiple linear regressions will be applied. The model is shown to be suitable because the results generate a good description of the fuel consumption behaviour. In the practical application of the method, the reduction of diesel consumption reached 10%. The implementation requires no large-scale investments or very long deadlines and can be applied to mining haulage operations in other settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preliminary study of the pilot's workload during emergency procedures in helicopters air operations.

PubMed

Bezerra, Flávio G V; Ribeiro, Selma L O

2012-01-01

Military air operations and law enforcement operations in helicopters are examples of activities that require high performance of the operator. This article aimed at presenting a preliminary analysis of data obtained in the initial study in order to validate the instruments and the research protocol that focuses on the analysis of the workload imposed on helicopter pilots in emergency situations. The research was conducted in an environment of real flight training and used the NASA-TLX Scale to assess the workload and an interview guide to obtain reports on the main tasks performed. Preliminary data obtained is related to the participation of 10 (ten) volunteer pilots with experience in different types of helicopters. Four scenarios involving helicopter emergency procedures of HB-350 "Squirrel" were outlined. For this article, the analysis used only the data regarding the Physical and Mental Demands of the NASA-TLX Scale. Preliminarily, the results indicate that the "time pressure" as a factor contributing to increase mental requirement in emergency situations in flight, and that this increase was reflected in the request of mental processes such as: identification of the breakdown, attention and monitoring parameters. Future steps include extending the sample and adding physiological tools to better understand the effects of these types of emergencies on pilot performance and flight safety.

Predictors and causes of unplanned re-operations in outpatient plastic surgery: a multi-institutional analysis of 6749 patients using the 2011 NSQIP database.

PubMed

Lim, Seokchun; Jordan, Sumanas W; Jain, Umang; Kim, John Y S

2014-08-01

Studies that evaluate the predictors and causes of unplanned re-operation in outpatient plastic surgery. This study retrospectively reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and identified all plastic surgery outpatient cases performed in 2011. Multiple logistic regression analysis was utilised to identify independent risk factors and causes of unplanned reoperations. Of the 6749 outpatient plastic surgery cases identified, there were 125 (1.9%) unplanned re-operations (UR). Regression analysis demonstrated that body mass index (BMI, OR = 1.041, 95% CI = 1.019-1.065), preoperative open wound/wound infection (OR = 3.498, 95% CI = 1.593-7.678), American Society of Anesthesiologists (ASA) class 3 (OR = 2.235, 95% CI = 1.048-4.765), and total work relative value units (RVU, OR = 1.014, 95% CI = 1.005-1.024) were significantly predictive of UR. Additionally, the presence of any complication was significantly associated with UR (OR = 15.065, 95% CI = 5.705-39.781). In an era of outcomes-driven medicine, unplanned re-operation is a critical quality indicator for ambulatory plastic surgery facilities. The identified risk factors will aid in surgical planning and risk adjustment.

Review Team Focused Modeling Analysis of Radial Collector Well Operation on the Hypersaline Groundwater Plume beneath the Turkey Point Site near Homestead, Florida

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

Oostrom, Martinus; Vail, Lance W.

Researchers at Pacific Northwest National Laboratory served as members of a U.S. Nuclear Regulatory Commission review team for the Florida Power & Light Company’s application for two combined construction permits and operating licenses (combined licenses or COLs) for two proposed new reactor units—Turkey Point Units 6 and 7. The review team evaluated the environmental impacts of the proposed action based on the October 29, 2014 revision of the COL application, including the Environmental Report, responses to requests for additional information, and supplemental information. As part of this effort, team members tasked with assessing the environmental effects of proposed construction andmore » operation of Units 6 and 7 at the Turkey Point site reviewed two separate modeling studies that analyzed the interaction between surface water and groundwater that would be altered by the operation of radial collector wells (RCWs) at the site. To further confirm their understanding of the groundwater hydrodynamics and to consider whether certain actions, proposed after the two earlier modeling studies were completed, would alter the earlier conclusions documented by the review team in their draft environmental impact statement (EIS; NRC 2015), a third modeling analysis was performed. The third modeling analysis is discussed in this report.« less

Using Operational Analysis to Improve Access to Pulmonary Function Testing.

PubMed

Ip, Ada; Asamoah-Barnieh, Raymond; Bischak, Diane P; Davidson, Warren J; Flemons, W Ward; Pendharkar, Sachin R

2016-01-01

Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment.

Iron therapy for pre-operative anaemia.

PubMed

Ng, Oliver; Keeler, Barrie D; Mishra, Amitabh; Simpson, Alastair; Neal, Keith; Brookes, Matthew J; Acheson, Austin G

2015-12-22

Pre-operative anaemia is common and occurs in up to 76% of patients. It is associated with increased peri-operative allogeneic blood transfusions, longer hospital lengths of stay and increased morbidity and mortality. Iron deficiency is one of the most common causes of this anaemia. Oral iron therapy has traditionally been used to treat anaemia but newer, safer parenteral iron preparations have been shown to be more effective in other conditions such as inflammatory bowel disease, chronic heart failure and post-partum haemorrhage. A limited number of studies look at iron therapy for the treatment of pre-operative anaemia. The aim of this Cochrane review is to summarise the evidence for use of iron supplementation, both enteral and parenteral, for the management of pre-operative anaemia. The objective of this review is to evaluate the effects of pre-operative iron therapy (enteral or parenteral) in reducing the need for allogeneic blood transfusions in anaemic patients undergoing surgery. We ran the search on 25 March 2015. We searched the Cochrane Injuries Group's Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), EMBASE Classic and EMBASE (Ovid), CINAHL Plus (EBSCO), PubMed, clinical trials registries, conference abstracts, and we screened reference lists. We included all randomised controlled trials (RCTs) which compared pre-operative iron monotherapy to placebo, no treatment, standard of care or another form of iron therapy for anaemic adults undergoing surgery. Anaemia was defined by haemoglobin values less than 13 g/dL for males and 12 g/dL for non-pregnant females. Data were collected by two authors on the proportion of patients who receive a blood transfusion, amount of blood transfused per patient (units) and haemoglobin measured as continuous variables at pre-determined time-points: pre-treatment, pre-operatively but post-treatment, and post-operatively. Statistical analysis was performed using the Cochrane statistical software, Review Manager 2014. Outcome data were summarised in tables and a forest plot. Three prospective randomised controlled studies evaluated pre-operative iron therapy to correct anaemia (two in colorectal and one in gynaecological surgery) and included 114 patients in total. One compared oral iron versus standard care (Lidder 2007); one intravenous iron versus control (Edwards 2009); and one study compared oral versus intravenous iron (Kim 2009). Both colorectal trials reported the primary outcome (proportion of patients who received allogeneic blood transfusions) and meta-analysis showed a reduction in blood transfusions with the administration of iron therapy, but the reduction was not statistically significant (risk ratio (RR) 0.56, 95% confidence interval (CI) 0.27 to 1.18). All studies reported haemoglobin change but data for the anaemic patients were only available for two studies (Edwards 2009 and Kim 2009). Edwards 2009 showed no difference in haemoglobin at the end of treatment pre-operatively. The intravenous versus oral iron study showed an increase in haemoglobin with intravenous iron at the end of treatment pre-operatively (MD 1.90 g/dL, 95% CI 1.16 to 2.64; participants = 56), but the results are at high risk of bias because participants with less than 80% compliance with therapy were excluded from the analysis and compliance was lower in the oral iron group due to the side-effects of treatment (Kim 2009).None of the studies reported quality of life, short- or long-term mortality or post-operative morbidity. The use of iron therapy for pre-operative anaemia does not show a statistically significant reduction in the proportion of patients who received an allogeneic blood transfusion compared to no iron therapy. However, the 38 patients in our analysis falls far short of the 819 patients our information size calculation recommended to detect a 30% reduction in blood transfusions. Intravenous iron may be more effective than oral iron at increasing haemoglobin. However, all these conclusions are drawn from only three small randomised controlled studies. Further well designed, adequately powered randomised controlled studies are required to determine the true effectiveness of iron therapy for pre-operative anaemia.

Experimental Design and Data Analysis in Receiver Operating Characteristic Studies: Lessons Learned from Reports in Radiology from 1997 to 20061

PubMed Central

Shiraishi, Junji; Pesce, Lorenzo L.; Metz, Charles E.; Doi, Kunio

2009-01-01

Purpose: To provide a broad perspective concerning the recent use of receiver operating characteristic (ROC) analysis in medical imaging by reviewing ROC studies published in Radiology between 1997 and 2006 for experimental design, imaging modality, medical condition, and ROC paradigm. Materials and Methods: Two hundred ninety-five studies were obtained by conducting a literature search with PubMed with two criteria: publication in Radiology between 1997 and 2006 and occurrence of the phrase “receiver operating characteristic.” Studies returned by the query that were not diagnostic imaging procedure performance evaluations were excluded. Characteristics of the remaining studies were tabulated. Results: Two hundred thirty-three (79.0%) of the 295 studies reported findings based on observers' diagnostic judgments or objective measurements. Forty-three (14.6%) did not include human observers, with most of these reporting an evaluation of a computer-aided diagnosis system or functional data obtained with computed tomography (CT) or magnetic resonance (MR) imaging. The remaining 19 (6.4%) studies were classified as reviews or meta-analyses and were excluded from our subsequent analysis. Among the various imaging modalities, MR imaging (46.0%) and CT (25.7%) were investigated most frequently. Approximately 60% (144 of 233) of ROC studies with human observers published in Radiology included three or fewer observers. Conclusion: ROC analysis is widely used in radiologic research, confirming its fundamental role in assessing diagnostic performance. However, the ROC studies reported in Radiology were not always adequate to support clear and clinically relevant conclusions. © RSNA, 2009 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2533081632/-/DC1 PMID:19864510

Factor analysis of financial and operational performance measures of non-profit hospitals.

PubMed

Das, Dhiman

2009-01-01

To understand the important dimensions of the financial and operational performance of non-profit hospitals. Secondary data for non-profit US hospitals between 1996 and 2004. I use iterative principal factor analysis of hospitals' financial and operational ratios for each year of the study. For factor interpretation, I use oblique rotation. Financial ratios were created using cost report data from HCRIS 2552-96 available from the Centers for Medicaid & Medicare Services (CMS). I identify five factors--capital structure, profitability, activity, liquidity, and an operational factor--that explain most of the variation in the performance of non-profit hospitals. I also find that capital structure is more important than profitability in determining the performance of these hospitals. The importance of capital structure highlights a significant shift in the organization of the non-profit hospitals' finances.

The minimum follow-up required for radial head arthroplasty: a meta-analysis.

PubMed

Laumonerie, P; Reina, N; Kerezoudis, P; Declaux, S; Tibbo, M E; Bonnevialle, N; Mansat, P

2017-12-01

The primary aim of this study was to define the standard minimum follow-up required to produce a reliable estimate of the rate of re-operation after radial head arthroplasty (RHA). The secondary objective was to define the leading reasons for re-operation. Four electronic databases, between January 2000 and March 2017 were searched. Articles reporting reasons for re-operation (Group I) and results (Group II) after RHA were included. In Group I, a meta-analysis was performed to obtain the standard minimum follow-up, the mean time to re-operation and the reason for failure. In Group II, the minimum follow-up for each study was compared with the standard minimum follow-up. A total of 40 studies were analysed: three were Group I and included 80 implants and 37 were Group II and included 1192 implants. In Group I, the mean time to re-operation was 1.37 years (0 to 11.25), the standard minimum follow-up was 3.25 years; painful loosening was the main indication for re-operation. In Group II, 33 Group II articles (89.2%) reported a minimum follow-up of < 3.25 years. The literature does not provide a reliable estimate of the rate of re-operation after RHA. The reproducibility of results would be improved by using a minimum follow-up of three years combined with a consensus of the definition of the reasons for failure after RHA. Cite this article: Bone Joint J 2017;99-B:1561-70. ©2017 The British Editorial Society of Bone & Joint Surgery.

Comparative analysis of the bacterial diversity in a lab-scale moving bed biofilm reactor (MBBR) applied to treat urban wastewater under different operational conditions.

PubMed

Calderón, Kadiya; Martín-Pascual, Jaime; Poyatos, José Manuel; Rodelas, Belén; González-Martínez, Alejandro; González-López, Jesús

2012-10-01

Different types of carriers were tested as support material in a lab-scale moving bed biofilm reactor (MBBR) used to treat urban wastewater under three different conditions of hydraulic retention time (HRT) and carrier filling ratios (FR). The bacterial diversity developed on the biofilms responsible of the treatment was studied using a cultivation-independent approach based on the polymerase chain reaction-temperature gradient gel electrophoresis technique (PCR-TGGE). Cluster analysis of TGGE fingerprints showed significant differences of community structure dependent upon the different operational conditions applied. Redundancy analysis (RDA) was used to determine the relationship between the operational conditions (type of carrier, HRT, FR) and bacterial biofilm diversity, demonstrating a significant effect of FR=50%. Phylogenetic analysis of PCR-reamplified and sequenced TGGE bands revealed that the prevalent Bacteria populations in the biofilm were related to Betaproteobacteria (46%), Firmicutes (34%),Alphaproteobacteria (14%) and Gammaproteobacteria (9%). Copyright © 2012 Elsevier Ltd. All rights reserved.

A Study of Multigrid Preconditioners Using Eigensystem Analysis

NASA Technical Reports Server (NTRS)

Roberts, Thomas W.; Swanson, R. C.

2005-01-01

The convergence properties of numerical schemes for partial differential equations are studied by examining the eigensystem of the discrete operator. This method of analysis is very general, and allows the effects of boundary conditions and grid nonuniformities to be examined directly. Algorithms for the Laplace equation and a two equation model hyperbolic system are examined.

Case Studies of Predictive Analysis Applications in Law Enforcement

DTIC Science & Technology

2015-12-01

analysis to crime problems to be considered effective. To test this hypothesis, case studies were conducted on municipal police departments in the...Forecasting in Law Enforcement Operations. 6 Vlahos, “The Department of Pre -Crime.” 4 studies were conducted on municipal police departments in the... case studies are described and recommendations for future research , as well as recommendations for police executives considering an investment in

Short-Term Load Forecasting Error Distributions and Implications for Renewable Integration Studies: Preprint

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

Hodge, B. M.; Lew, D.; Milligan, M.

2013-01-01

Load forecasting in the day-ahead timescale is a critical aspect of power system operations that is used in the unit commitment process. It is also an important factor in renewable energy integration studies, where the combination of load and wind or solar forecasting techniques create the net load uncertainty that must be managed by the economic dispatch process or with suitable reserves. An understanding of that load forecasting errors that may be expected in this process can lead to better decisions about the amount of reserves necessary to compensate errors. In this work, we performed a statistical analysis of themore » day-ahead (and two-day-ahead) load forecasting errors observed in two independent system operators for a one-year period. Comparisons were made with the normal distribution commonly assumed in power system operation simulations used for renewable power integration studies. Further analysis identified time periods when the load is more likely to be under- or overforecast.« less

An Analysis of United States Marine Corps Enlisted Entry-Level Training Using Supply Chain and Operations Management

DTIC Science & Technology

2010-12-01

An Analysis of United States Marine Corps Enlisted Entry-Level Training Using Supply Chain and Operations Management ______________________________________ By...Report 4. TITLE AND SUBTITLE: An Analysis of United States Marine Corps Enlisted Entry-Level Training Using Supply Chain and Operations Management 6...Level Training; United States Marine Corps; Operations Management ; Supply Chain Management; Process Analysis 16. PRICE CODE 17. SECURITY

Space station system analysis study. Part 3: Documentation. Volume 2: Technical report. [structural design and construction

NASA Technical Reports Server (NTRS)

1977-01-01

An analysis of construction operation is presented as well as power system sizing requirements. Mission hardware requirements are reviewed in detail. Space construction base and design configurations are also examined.

Electronic credentialing for commercial vehicle operations : a cross-cutting analysis

DOT National Transportation Integrated Search

1999-06-10

This case study presents an analysis of how Maryland, Virginia, and Kentucky have used the Commercial Vehicle Information Systems & Networks (CVISN) Architecture to develop state CVISN systems designs for electronic credentialing. Focus is on the CVI...

Vehicle operation characteristic under different ramp entrance conditions in underground road: Analysis, simulation and modelling

NASA Astrophysics Data System (ADS)

Yao, Qiming; Liu, Shuo; Liu, Yang

2018-05-01

An experimental design was used to study the vehicle operation characteristics of different ramp entrance conditions in underground road. With driving simulator, the experimental scenarios include left or right ramp with first, second and third service level, respectively, to collect vehicle speed, acceleration, lateral displacement and location information at the ramp entrance section. By using paired t-test and ANOVA, the influence factors of vehicle operating characteristics are studied. The result shows that effects of ramp layout and mainline traffic environment on vehicle operation characteristics are significant. The regression model of vehicle traveling distance on acceleration lane is established. Suggestions are made for ramp entrance design of underground road.

FBI fingerprint identification automation study. AIDS 3 evaluation report. Volume 3: Operational feasibility

NASA Technical Reports Server (NTRS)

Mulhall, B. D. L.

1980-01-01

An evaluation is presented which is defined as the adequacy of system design with known functional and performance requirements. The proposed Rockwell International AIDS 3 card, document and data flow are presented to summarize the concepts involved and the relationships between functions. The analysis and evaluation includes a study of system capability, processing rates, search requirements and response accuracy as well as a consideration of operational components and hardware integration. Results indicate that the AIDS 3 System concept is operationally feasible if production capacity is slightly enhanced but that operational complexity, hardware integration and a lack of conceptual data pertinent to some of the functions are areas of concern.

Analysis of operational requirements for medium density air transportation. Volume 1: Summary

NASA Technical Reports Server (NTRS)

1975-01-01

The medium density air travel market was studied to determine the aircraft design and operational requirements. The impact of operational characteristics on the air travel system and the economic viability of the study aircraft were also evaluated. Medium density is defined in terms of numbers of people transported (20 to 500 passengers per day on round trip routes), and frequency of service ( a minumium of two and maximum of eight round trips per day) for 10 regional carriers. The operational characteristics of aircraft best suited to serve the medium density air transportation market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations could be conducted. The impact of selected aircraft on the medium density market, economics, and operations is ascertained. Research and technology objectives for future programs in medium density air transportation are identified and ranked.

Study on the steady operating state of a micro-pulse electron gun.

PubMed

Kui, Zhou; Xiangyang, Lu; Shengwen, Quan; Jifei, Zhao; Xing, Luo; Ziqin, Yang

2014-09-01

Micro-pulse electron gun (MPG) employs the basic concept of multipacting to produce high-current and short-pulse electron beams from a radio-frequency (RF) cavity. The concept of MPG has been proposed for more than two decades. However, the unstable operating state of MPG vastly obstructs its practical applications. This paper presents a study on the steady operating state of a micro-pulse electron gun with theory and experiments. The requirements for the steady operating state are proposed through the analysis of the interaction between the RF cavity and the beam load. Accordingly, a MPG cavity with the frequency of 2856 MHz has been designed, constructed, and tested. Some primary experiments have been finished. Both the unstable and stable operating states of the MPG have been observed. The stable output beam current has been detected at about 3.8 mA. Further experimental study is under way now.

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING THE DOUBLE-BUNDLE TECHNIQUE - EVALUATION IN THE BIOMECHANICS LABORATORY.

PubMed

D'Elia, Caio Oliveira; Bitar, Alexandre Carneiro; Castropil, Wagner; Garofo, Antônio Guilherme Padovani; Cantuária, Anita Lopes; Orselli, Maria Isabel Veras; Luques, Isabela Ugo; Duarte, Marcos

2011-01-01

The objective of this study was to describe the methodology of knee rotation analysis using biomechanics laboratory instruments and to present the preliminary results from a comparative study on patients who underwent anterior cruciate ligament (ACL) reconstruction using the double-bundle technique. The protocol currently used in our laboratory was described. Three-dimensional kinematic analysis was performed and knee rotation amplitude was measured on eight normal patients (control group) and 12 patients who were operated using the double-bundle technique, by means of three tasks in the biomechanics laboratory. No significant differences between operated and non-operated sides were shown in relation to the mean amplitudes of gait, gait with change in direction or gait with change in direction when going down stairs (p > 0.13). The preliminary results did not show any difference in the double-bundle ACL reconstruction technique in relation to the contralateral side and the control group.

Interpreting cost of ownership for mix-and-match lithography

NASA Astrophysics Data System (ADS)

Levine, Alan L.; Bergendahl, Albert S.

1994-05-01

Cost of ownership modeling is a critical and emerging tool that provides significant insight into the ways to optimize device manufacturing costs. The development of a model to deal with a particular application, mix-and-match lithography, was performed in order to determine the level of cost savings and the optimum ways to create these savings. The use of sensitivity analysis with cost of ownership allows the user to make accurate trade-offs between technology and cost. The use and interpretation of the model results are described in this paper. Parameters analyzed include several manufacturing considerations -- depreciation, maintenance, engineering and operator labor, floorspace, resist, consumables and reticles. Inherent in this study is the ability to customize this analysis for a particular operating environment. Results demonstrate the clear advantages of a mix-and-match approach for three different operating environments. These case studies also demonstrate various methods to efficiently optimize cost savings strategies.

Man/Machine Interaction Dynamics And Performance (MMIDAP) capability

NASA Technical Reports Server (NTRS)

Frisch, Harold P.

1991-01-01

The creation of an ability to study interaction dynamics between a machine and its human operator can be approached from a myriad of directions. The Man/Machine Interaction Dynamics and Performance (MMIDAP) project seeks to create an ability to study the consequences of machine design alternatives relative to the performance of both machine and operator. The class of machines to which this study is directed includes those that require the intelligent physical exertions of a human operator. While Goddard's Flight Telerobotic's program was expected to be a major user, basic engineering design and biomedical applications reach far beyond telerobotics. Ongoing efforts are outlined of the GSFC and its University and small business collaborators to integrate both human performance and musculoskeletal data bases with analysis capabilities necessary to enable the study of dynamic actions, reactions, and performance of coupled machine/operator systems.

Identifying Indirect Benefits of Federal Health Care Emergency Preparedness Grant Funding to Coalitions: A Content Analysis.

PubMed

Priest, Chad; Stryckman, Benoit

2015-12-01

This study aimed to identify the indirect benefits of health care preparedness funding as perceived by current and former recipients of the US Department of Health and Human Services Office of the Assistant Secretary for Preparedness and Response's Hospital Preparedness Program. This was a qualitative inductive content analysis of telephone interviews conducted with regional stakeholders from several health care coalitions to identify their perceptions of the indirect benefits of preparedness funding. Content analysis of interviewee responses resulted in 2 main categories of indirect benefits of federal health care preparedness funding: (1) dual-use technology and programs and (2) impact of relationships on day-to-day operations. Within the dual-use technology and programs category, 3 subcategories were identified: (1) information systems, (2) clinical technology, and (3) health care operations. Similarly, 3 subcategories relating to the indirect benefits in the impact of relationships on day-to-day operations category were identified: (1) cooperation, (2) information sharing, and (3) sense of community. This study identified indirect benefits of federal investment in hospital and health care preparedness in day-to-day operations. Major categories of these benefits included dual-use technology and programs and impact of relationships on day-to-day operations. Coalition members placed a high value on these benefits, even though they were not direct outcomes of grant programs. Further research is needed to quantify the economic value of these indirect benefits to more accurately measure the total return on investment from federal grant funding.

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR PERFORMANCE OF ANALYSES ON NHEXAS DATA (IIT-A-3.0)

EPA Science Inventory

The purpose of this SOP is to define the procedures for the analysis of NHEXAS and Border study data. These methods were used for all data analysis associated with the Arizona NHEXAS project and the Border study at the Illinois Institute of Technology (IIT) site. Keywords: data;...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE--COMPENDIUM OF METHODS FOR ANALYSIS OF TRACE METALS AND PESTICIDES IN DIETARY SAMPLES USING TOTAL DIET STUDY PROCEDURES (FDA-COMPENDIUM)

EPA Science Inventory

This compendium contains seven SOPs developed by Food and Drug Administration (FDA) laboratories for methods of analyzing trace metals in dietary samples collected using Total Diet study procedures. The SOPs include the following: (1) Quality Control for Analysis of NHEXAS Food o...

A Preliminary Study: USMC Tactical Communications Technical Control Needs for the Landing Force Integrated Communications System.

DTIC Science & Technology

1985-09-01

BSTRACT This study uses a systems analysis approach to determine the communications technical control needs of the Fleet Marine Force as the transition...subsequent analysis and decision. In the acquisi- tion of military systems, it is typical to find these assumptions used to construct various measures of...relatively free from the typical underlying estimates used in cost and operational effective- ness analysis (COEA) type studies which are designed to compare

Analysis of Mission Effectiveness: Modern System Architecture Tools for Project Developers

DTIC Science & Technology

2017-12-01

operator input and scripted instructions to describe low-level flow. Note that the case study in Chapter IV describes one pass through evaluation...capability of the sensors. A constraint on the case study is that each sensor type must cover the entire operations area. Cost is a function of 53...completed. 5. Assessment This case study focuses on the first recursive refinement phase completed in a multi-phase effort to demonstrate the effects

SEASAT economic assessment. Volume 2: The SEASAT system description and performance. [performance prediction and systems analysis for seasat satellites

NASA Technical Reports Server (NTRS)

1975-01-01

Results are presented of preliminary trade-off studies of operational SEASAT systems. The trade-off studies were used as the basis for the estimation of costs and net benefits of the operational SEASAT system. Also presented are the preliminary results of simulation studies that were designed to lead to a measure of the impact of SEASAT data through the use of numerical weather forecast models.

A 3 MV Pelletron at Fudan University

NASA Astrophysics Data System (ADS)

Sun, Chuan-Chen; Lu, Cheng-Rong; Fe, Zhi-Yu; Yuan, Dao-Sheng; Yang, Fujia

1989-04-01

A 3 MV Pelletron tandem, model 9SDH-2, the fourth machine manufactured by NEC was installed and has been operating at Fudan University since 1987. The operating experiences obtained during the past year are described. Three beam lines have been established: one is for Auger-ESCA and RBS in an ultrahigh-vacuum chamber in which Al(100) clean surfaces have been studied; the second beam line is used as a mubeam analysis system using a 2 μ proton beam for resonant prefitting studies. The third is a general purpose beam line, for studies of the effect of nuclear resonance on K X-ray yield. At present, the third beam line is also used for ion beam analysis studies of 8.8 MeV He 2+ non-Rutherford scattering on high Tc superconductors.

Parametric study of closed wet cooling tower thermal performance

NASA Astrophysics Data System (ADS)

Qasim, S. M.; Hayder, M. J.

2017-08-01

The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.

How do strategic decisions and operative practices affect operating room productivity?

PubMed

Peltokorpi, Antti

2011-12-01

Surgical operating rooms are cost-intensive parts of health service production. Managing operating units efficiently is essential when hospitals and healthcare systems aim to maximize health outcomes with limited resources. Previous research about operating room management has focused on studying the effect of management practices and decisions on efficiency by utilizing mainly modeling approach or before-after analysis in single hospital case. The purpose of this research is to analyze the synergic effect of strategic decisions and operative management practices on operating room productivity and to use a multiple case study method enabling statistical hypothesis testing with empirical data. 11 hypotheses that propose connections between the use of strategic and operative practices and productivity were tested in a multi-hospital study that included 26 units. The results indicate that operative practices, such as personnel management, case scheduling and performance measurement, affect productivity more remarkably than do strategic decisions that relate to, e.g., units' size, scope or academic status. Units with different strategic positions should apply different operative practices: Focused hospital units benefit most from sophisticated case scheduling and parallel processing whereas central and ambulatory units should apply flexible working hours, incentives and multi-skilled personnel. Operating units should be more active in applying management practices which are adequate for their strategic orientation.

Interactive digital signal processor

NASA Technical Reports Server (NTRS)

Mish, W. H.; Wenger, R. M.; Behannon, K. W.; Byrnes, J. B.

1982-01-01

The Interactive Digital Signal Processor (IDSP) is examined. It consists of a set of time series analysis Operators each of which operates on an input file to produce an output file. The operators can be executed in any order that makes sense and recursively, if desired. The operators are the various algorithms used in digital time series analysis work. User written operators can be easily interfaced to the sysatem. The system can be operated both interactively and in batch mode. In IDSP a file can consist of up to n (currently n=8) simultaneous time series. IDSP currently includes over thirty standard operators that range from Fourier transform operations, design and application of digital filters, eigenvalue analysis, to operators that provide graphical output, allow batch operation, editing and display information.

Factors Associated with Salmonella Prevalence in U.S. Swine Grower-Finisher Operations, 2012.

PubMed

Bjork, Kathe E; Fields, Victoria; Garber, Lindsey P; Kopral, Christine A

2018-05-15

Nontyphoidal Salmonella is an important foodborne pathogen with diverse serotypes occurring in animal and human populations. The prevalence of the organism on swine farms has been associated with numerous risk factors, and although there are strong veterinary public health controls for preventing Salmonella from entering food, there remains interest in eradicating or controlling the organism in the preharvest environment. In this study, using data collected via the U.S. Department of Agriculture (USDA) National Animal Health Monitoring System Swine 2012 study, we describe nontyphoidal Salmonella and specific serotype prevalence on U.S. grower-finisher swine operations and investigate associations between Salmonella detection and numerous factors via multiple correspondence analysis (MCA) and regression analysis. MCA plots, complementary to univariate analyses, display relationships between covariates and Salmonella detection at the farm level. In the univariate analysis, Salmonella detection varied with feed characteristics and farm management practices, reports of diseases on farms and vaccinations administered, and administration of certain antimicrobials. Results from the univariate analysis reinforce the importance of biosecurity in managing diseases and pathogens such as Salmonella on farms. All multivariable regression models for the likelihood of Salmonella detection were strongly affected by multicollinearity among variables, and only one variable, pelleted feed preparation, remained in the final model. The study was limited by its cross-sectional nature, timelines of data collection, and reliance on operator-reported data via a convenience sample.

Manned systems utilization analysis (study 2.1). Volume 5: Program listing for the LOVES computer code

NASA Technical Reports Server (NTRS)

Wray, S. T., Jr.

1975-01-01

The LOVES computer code developed to investigate the concept of space servicing operational satellites as an alternative to replacing expendable satellites or returning satellites to earth for ground refurbishment is presented. In addition to having the capability to simulate the expendable satellite operation and the ground refurbished satellite operation, the program is designed to simulate the logistics of space servicing satellites using an upper stage vehicle and/or the earth to orbit shuttle. The program not only provides for the initial deployment of the satellite but also simulates the random failure and subsequent replacement of various equipment modules comprising the satellite. The program has been used primarily to conduct trade studies and/or parametric studies of various space program operational philosophies.

Surgical Management and Outcomes of Ebstein Anomaly in Neonates and Infants: A Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis.

PubMed

Holst, Kimberly A; Dearani, Joseph A; Said, Sameh M; Davies, Ryan R; Pizarro, Christian; Knott-Craig, Christopher; Kumar, T K Susheel; Starnes, Vaughn; Kumar, S Ram; Pasquali, Sara K; Thibault, Dylan P; Meza, James M; Hill, Kevin D; Chiswell, Karen; Jacobs, Jeffrey P; Jacobs, Marshall L

2018-05-16

Ebstein anomaly (EA) encompasses a broad spectrum of morphology and clinical presentation. Those who are symptomatic early in infancy are generally at highest risk, but there are limited data regarding multi-centric practice patterns and outcomes. We analyzed multi-institutional data concerning operations and outcomes in neonates and infants with EA. Index operations reported in the STS Congenital Heart Surgery Database (2010-2016) were potentially eligible for inclusion. Analysis was limited to patients with diagnosis of Ebstein anomaly and less than 1 year of age at time of surgery (neonates ≤30 days, infants 31-365 days). The study population included 255 neonates and 239 infants (at 95 centers). Among neonates, median age at operation was 7 days (IQR 4-13) and the majority required preoperative ventilation (61.6%, 157). The most common primary operation performed among neonates was Ebstein repair (39.6%, 101) followed by systemic to pulmonary shunt (20.4%, 52) and tricuspid valve closure (9.4%, 24). Overall neonatal operative mortality was 27.4% (70) with composite morbidity-mortality of 51.4% (48). For infants, median age at operation was 179 days (6 months); the most common primary operation for infants was superior cavopulmonary anastomosis (38.1%, 91) followed by Ebstein repair (15.5%, 37). Overall operative mortality for infants was 9.2% (22) with composite morbidity-mortality of 20.1% (48). Symptomatic EA in early infancy is very high risk and a variety of operative procedures were performed. A dedicated prospective study is required to more fully understand optimal selection of treatment pathways to guide a systematic approach to operative management. Copyright © 2018. Published by Elsevier Inc.

Does the United States’ Strategic Mobility Program Support the Needs of Operational Commanders

DTIC Science & Technology

2010-10-01

Does the United States’ Strategic Mobility Program Support the Needs of Operational Commanders? A Monograph by MAJ Erik E. Hilberg United...inability to project certain capabilities? This monograph argues that the Department of Defense’s shortfalls in strategic sealift will limit a ground...quantitative research associated with this study goes through a qualitative analysis. The research results of this study then undergo an examination

A System for Analyzing the Cost of Operating Vocational Education Programs at the Secondary Level in Ohio. A Study of School Year 1973-1974.

ERIC Educational Resources Information Center

Ohio State Dept. of Education, Columbus.

As a part of Ohio's program review and evaluation of vocational education, the report is concerned with a study of the costs of operating vocational education programs throughout the State. A cost analysis system for secondary level vocational education instructional programs was developed in 1970 and has been restudied each succeeding year. The…

Some legal, jurisdictional, and operational implications of a congressional technology assessment component

NASA Technical Reports Server (NTRS)

Mayo, L. H.

1975-01-01

An analysis is presented for the Congress of the relationships between an institutionalized assessment function and legislative information gathering and decisionmaking needs. The study was directed to the following topics: (1) the positing of a hypothetical technology assessment component for legislative support; (2) the posing of a number of questions relating to the operational context of this assessment component including the organization/operational framework, general operational problems, access to relevant information, and the utilization of assessment data and analyses; and (3) some selected comments relevant to the questions posed.

Weather Radar Studies

DTIC Science & Technology

1988-03-31

radar operation and data - collection activities, a large data -analysis effort has been under way in support of automatic wind-shear detection algorithm ...REDUCTION AND ALGORITHM DEVELOPMENT 49 A. General-Purpose Software 49 B. Concurrent Computer Systems 49 C. Sun Workstations 51 D. Radar Data Analysis 52...1. Algorithm Verification 52 2. Other Studies 53 3. Translations 54 4. Outside Distributions 55 E. Mesonet/LLWAS Data Analysis 55 1. 1985 Data 55 2

A two-stage method of quantitative flood risk analysis for reservoir real-time operation using ensemble-based hydrologic forecasts

NASA Astrophysics Data System (ADS)

Liu, P.

2013-12-01

Quantitative analysis of the risk for reservoir real-time operation is a hard task owing to the difficulty of accurate description of inflow uncertainties. The ensemble-based hydrologic forecasts directly depict the inflows not only the marginal distributions but also their persistence via scenarios. This motivates us to analyze the reservoir real-time operating risk with ensemble-based hydrologic forecasts as inputs. A method is developed by using the forecast horizon point to divide the future time into two stages, the forecast lead-time and the unpredicted time. The risk within the forecast lead-time is computed based on counting the failure number of forecast scenarios, and the risk in the unpredicted time is estimated using reservoir routing with the design floods and the reservoir water levels of forecast horizon point. As a result, a two-stage risk analysis method is set up to quantify the entire flood risks by defining the ratio of the number of scenarios that excessive the critical value to the total number of scenarios. The China's Three Gorges Reservoir (TGR) is selected as a case study, where the parameter and precipitation uncertainties are implemented to produce ensemble-based hydrologic forecasts. The Bayesian inference, Markov Chain Monte Carlo, is used to account for the parameter uncertainty. Two reservoir operation schemes, the real operated and scenario optimization, are evaluated for the flood risks and hydropower profits analysis. With the 2010 flood, it is found that the improvement of the hydrologic forecast accuracy is unnecessary to decrease the reservoir real-time operation risk, and most risks are from the forecast lead-time. It is therefore valuable to decrease the avarice of ensemble-based hydrologic forecasts with less bias for a reservoir operational purpose.

Thermodynamic Analysis of Dual-Mode Scramjet Engine Operation and Performance

NASA Technical Reports Server (NTRS)

Riggins, David; Tacket, Regan; Taylor, Trent; Auslender, Aaron

2006-01-01

Recent analytical advances in understanding the performance continuum (the thermodynamic spectrum) for air-breathing engines based on fundamental second-law considerations have clarified scramjet and ramjet operation, performance, and characteristics. Second-law based analysis is extended specifically in this work to clarify and describe the performance characteristics for dual-mode scramjet operation in the mid-speed range of flight Mach 4 to 7. This is done by a fundamental investigation of the complex but predictable interplay between heat release and irreversibilities in such an engine; results demonstrate the flow and performance character of the dual mode regime and of dual mode transition behavior. Both analytical and computational (multi-dimensional CFD) studies of sample dual-mode flow-fields are performed in order to demonstrate the second-law capability and performance and operability issues. The impact of the dual-mode regime is found to be characterized by decreasing overall irreversibility with increasing heat release, within the operability limits of the system.

An Emperical Analysis of the Corperate Ownership Concentration on the Operation Performance after IPOs of Chinese listed SMEs

NASA Astrophysics Data System (ADS)

Jiming, Li; Xing, Sun

The purpose of this paper is to investigates whether the large shareholders of small and medium firms (SMEs) take advantage of the inside information and decrease their shares before their operation performance begins to decline after the Initial Public Offerings (IPOs). By using the data from annual reports of SMEs listed on Shenzhen Stock Exchange in China from 2004 to 2006, this study explores both the relationship and the interaction effects between the change of operation performance and the ownership concentration of SMEs around their IPOs. The statistic analysis indicates that there is a significantly positive relationship between the ownership concentration and their operation performance after IPOs during the sample period. Moreover, the companies with higher ownership decreasing encounter more severe operation performance decline, which sugests that the listed companies intend to package their book profits before IPOs for the sake of increasing their issuing prices and enlarge their financing scales.

Trainee-Associated Factors and Proficiency at Percutaneous Nephrolithotomy.

PubMed

Aghamir, Seyed Mohammad Kazem; Behtash, Negar; Hamidi, Morteza; Farahmand, Hasan; Salavati, Alborz; Mortaz Hejri, Sara

2017-07-01

Percutaneous nephrolithotomy (PNL) is a complicated procedure for urology trainees. This study was designed to investigate the effect of trainees' ages and previous experience, as well as the number of operated cases, on proficiency at PNL by using patient outcomes. A cross sectional observational study was designed during a five-year period. Trainees in PNL fellowship programs were included. At the end of the program, the trainees' performance in PNL was assessed regarding five competencies and scored 1-5. If the overall score was 4 or above, the trainee was considered as proficient. The trainees' age at the beginning of the program and the years passed from their residency graduation were asked and recorded. Also, the number of PNL cases operated by each trainee was obtained via their logbooks. The age, years passed from graduation, and number of operated cases were compared between two groups of proficient and non-proficient trainees. Univariate and multivariate binary logistic regression analysis was applied to estimate the effect of aforementioned variables on the occurrence of the proficiency. Forty-two trainees were included in the study. The mean and standard deviation for the overall score were 3.40 (out of 5) and 0.67, respectively. Eleven trainees (26.2%) recognized as proficient in performing PNL. Univariate regression analysis indicated that each of three variables (age, years passed from graduation and number of operated cases) had statistically significant effect on proficiency. However, the multivariate regression analysis revealed that just the number of cases had significant effect on achieving proficiency. Although it might be assumed that trainees' age negatively correlates with their scores, in fact, it is their amount of practice that makes a difference. A certain number of cases is required to be operated by a trainee in order to reach the desired competency in PNL.

[Non operative treatment for perforated peptic ulcer: results of a prospective study].

PubMed

Songne, B; Jean, F; Foulatier, O; Khalil, H; Scotté, M

2004-12-01

The conservative management of perforated peptic ulcer has not gained widespread acceptance despite introduction of proton-pomp inhibitors because surgical procedures can achieve immediate closure by eventually using a laparoscopic approach. The aim of this prospective study was to evaluate the results of Taylor's method and to identify predictive factors of failure of medical treatment in patients presenting with perforated peptic ulcer. Between 1990 and 2000, 82 consecutive patients, with diagnosis of perforated peptic ulcer were prospectively included in this study. They were initially treated with non-operative procedure (nasogastric suction and intravenous administration of H2-blockers or proton-pomp inhibitors). No clinical improvement after 24 hours required a surgical treatment. Predictive factors of failure of non-operative treatment were tested in univariate or multivariate analysis. Clinical improvement was obtained with non-operative treatment in 54% of the patients (44/82). The overall mortality rate was 1%. In univariate analysis, significant predictive factors of failure of non-operative treatment were: size of pneumoperitoneum, heart beat >94 bpm, abdominal meteorism, pain at digital rectal exam, and age >59 years. In multivariate analysis, the significant factors were the size of pneumoperitoneum, heart beat, and abdominal meteorism. The association of these criteria: size of pneumoperitoneum >size of the first lumbar vertebra, heart beat >94 bpm, pain at digital rectal exam and age > 59 years , led to surgical treatment in all cases. These results suggest that more than 50% of patients with perforated peptic ulcer respond to conservative treatment without surgery and that the association of few criteria (size of pneumoperitoneum, heart beat, pain at digital rectal exam and age) require emergency surgery.

Orbital transfer vehicle concept definition and system analysis study, 1986. Volume 9: Study extension results

NASA Technical Reports Server (NTRS)

Kofal, Allen E.

1987-01-01

The purpose of this extension to the OTV Concept Definition and Systems Analysis Study was to improve the definition of the OTV Program that will be most beneficial to the nation in the 1995 to 2010 timeframe. The implications of the defined mission and defined launch vehicle are investigated. The key mission requirements identified for the Space Transportation Architecture Study (STAS) were established and reflect a need for early capability and more ambitious capability growth. The key technical objectives and related issues addressed are summarized. The analyses of selected areas including aerobrake design, proximity operations, and the balance of EVA and IVA operations used in the support of the OTV at the space-base were enhanced. Sensitivity studies were conducted to establish how the OTV program should be tailored to meet changing circumstances.

Ergonomic analysis of fastening vibration based on ISO Standard 5349 (2001).

PubMed

Joshi, Akul; Leu, Ming; Murray, Susan

2012-11-01

Hand-held power tools used for fastening operations exert high dynamic forces on the operator's hand-arm, potentially causing injuries to the operator in the long run. This paper presents a study that analyzed the vibrations exerted by two hand-held power tools used for fastening operations with the operating exhibiting different postures. The two pneumatic tools, a right-angled nut-runner and an offset pistol-grip, are used to install shearing-type fasteners. A tri-axial accelerometer is used to measure the tool's vibration. The position and orientation of the transducer mounted on the tool follows the ISO-5349 Standard. The measured vibration data is used to compare the two power tools at different operating postures. The data analysis determines the number of years required to reach a 10% probability of developing finger blanching. The results indicate that the pistol-grip tool induces more vibration in the hand-arm than the right-angled nut-runner and that the vibrations exerted on the hand-arm vary for different postures. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Space Operations Center system analysis study extension. Volume 2: Programmatics and cost

NASA Technical Reports Server (NTRS)

1982-01-01

A summary of Space Operations Center (SOC) orbital space station costs, program options and program recommendations is presented. Program structure, hardware commonality, schedules and program phasing are considered. Program options are analyzed with respect to mission needs, design and technology options, and anticipated funding constraints. Design and system options are discussed.

Analysing Teachers' Operations When Teaching Students: What Constitutes Scientific Theories?

ERIC Educational Resources Information Center

Holmqvist, Mona O.; Olander, Clas

2017-01-01

The aim of the study is to analyse teachers' efforts to develop secondary school students' knowledge and argumentation skills of what constitutes scientific theories. The analysis is based on Leontiev's three-level structure of activity (activity, action, and operation), as these levels correspond to the questions why, what, and how content is…

The water quality and quantity effects of biofuel operations in pine plantations of the southeastern USA

Treesearch

J. Nettles; M. Youssef; J. Cacho; J. Grace; Z. Leggett; E. Sucre

2011-01-01

Working alongside operational trials, a comprehensive research programme was developed to evaluate sustainability, life-cycle analysis, soil productivity, wildlife, and water resource impacts. The hydrology field studies consist of three sets of forested watersheds, each with mid-rotation pine reference, switchgrass (Panicum virgatum) interplanted, typical...

Analysis of Student Loan Special Rate Allowances and Servicing Costs.

ERIC Educational Resources Information Center

Technology Management, Inc., Cambridge, MA.

This document addresses two separate, though related aspects of the operation of the Guaranteed Student Loan Program (GSLP): (1) the mechanism for setting the special rate allowance (SRA); and (2) the effect of the operating requirements of the program on lender servicing costs. The study develops recommendations for improving both aspects of the…

In-space propellant systems safety. Volume 3: System safety analysis

NASA Technical Reports Server (NTRS)

1972-01-01

The primary objective was to examine from a system safety viewpoint in-space propellant logistic elements and operations to define the potential hazards and to recommend means to reduce, eliminate or control them. A secondary objective was to conduct trade studies of specific systems or operations to determine the safest of alternate approaches.

Epidural versus local anaesthetic infiltration via wound catheters in open liver resection: a meta-analysis.

PubMed

Bell, Richard; Pandanaboyana, Sanjay; Prasad, K Raj

2015-01-01

This meta-analysis was designed to systematically analyse all published studies comparing local anaesthetic infiltration with wound catheters and epidural catheters in open liver resection. A literature search was performed using the Cochrane Colorectal Cancer Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials in the Cochrane Library, MEDLINE, Embase and Science Citation Index Expanded. Randomized trials, and prospective and retrospective studies comparing wound catheters with epidural catheters were included. Statistical analysis was performed using Review Manager Version 5.2 software. The primary outcome measures were pain scores in the post-operative period operation. Secondary outcome measures were hospital stay, time to opening bowels, overall complications and analgesia-specific complications. Four studies including 705 patients were included in the analysis. The pain scores were significantly lower in those patients with epidural on the first post-operative day (POD) (mean difference of -0.90 [-1.29, -0.52], Z = 4.61) (P < 0.00001) with comparable pain scores on PODs 2 and 3. There was no significant difference in the time to opening bowels, opioid use and hospital stay between the techniques. The post-operative complication rate was higher in the epidural group (risk ratio 1.40 [1.07, 1.83]; χ(2) = 0.60, df = 1) (P = 0.44); I(2) = 0%; Z = 2.42 (P = 0.02). Local anaesthetic infiltration via wound catheters combined with patient-controlled opiate analgesia provides comparable pain relief to epidural catheters except for the first POD. Both techniques are associated with similar hospital stay and opioid use with wound catheters associated with lower complication rate. © 2014 Royal Australasian College of Surgeons.

Anthropometric assessment of crane cabins and recommendations for design: A case study.

PubMed

Zunjic, Aleksandar; Brkic, Vesna Spasojevic; Klarin, Milivoj; Brkic, Aleksandar; Krstic, Dragan

2015-01-01

Work of crane operators is very difficult and demanding. Therefore, it is very important that the cabin of a crane be designed on the basis of relevant anthropometric data. However, it is very difficult to find a research that considers anthropometric convenience of crane cabins. From the theoretical viewpoint, it is important to perceive and to classify effects of the anthropometric incompatibility of crane cabins. Globally, the objective is to consider the anthropometric convenience of existing crane cabins, and possibilities for improvements of their design from the ergonomic point of view. In this regard, it is significant to detect constraints that impede or hinder the work of the crane operators, which could be overcome with certain anthropometric solutions. The main objective is to examine whether and to what extent is justifiable to use anthropometric data that are obtained on the basis of general (national) population, during designing the crane cabins. For the assessment of existing crane cabins and the work of operators, four methods were used: observation of the work of the operators and design solutions of the cabins, the checklist approach, interviewing of operators and the experimental research based on obtaining the data on the population of crane operators. Results of the analysis based on the method of observation, analysis based on the application of the checklist, as well as interviewing of the operators indicate that certain construction constraints of the components in the cabins are the main reasons of reduced visibility and improper working postures of operators. All this has caused the emergence of continuous musculoskeletal loading of the crane operators. The results of the anthropometric research that were obtained on the population of crane operators in this case study suggest that there is a statistically significant difference, when compared data of this population of workers with anthropometric data from the general population. Analyzed workplaces in crane cabins do not correspond to the majority of operators from the anthropometric standpoint. The conducted anthropometric analysis has been indicated that could be made the mistake, if dimensions of the cabin and layout of equipment would be relied on data derived from the general population of citizens. In order to achieve greater precision in the design and configuration of equipment, it is recommended using the data that are obtained directly on the population of the crane operators when designing the cabin.

Systems Analysis in Small Educational Systems: A Case Study.

ERIC Educational Resources Information Center

Vazquez-Abad, Jesus; And Others

1982-01-01

The use of systems analysis in transforming a graduate program in educational technology from a lecture-based system to a self-instructional one is described. Several operational research techniques are illustrated. A bibliography of 10 items is included. (CHC)

Analysis and Operational Feasibility of Potable Water Production

DTIC Science & Technology

2015-09-01

III. MODELING, SIMULATION, AND TEST RESULTS ANALYSIS ..............27 A. INTRODUCTION...Regions of Study ......................57 Table 10. Drinking Water Tests ...chemicals, and coliform bacteria. Testing of the condensed water is important to ensure potability, as common tests have been conducted to ensure

A precursor system analysis of automated construction, maintenance, and operational requirements : resource materials

DOT National Transportation Integrated Search

1995-03-01

This report documents work performed by the University of California at Davis in collaboration with the California Department of Transportation (Caltrans) in relationship to a Precursor System Analysis dealing with a study of automated construction, ...

Airport Surface Traffic Control Concept Formulation Study : Volume 1. Executive Summary.

DOT National Transportation Integrated Search

1975-07-01

The report describes the approach followed and the analysis techniques employed in the performance of the operations analysis of the current ASTC system for the baseline airport, O'Hare International Airport, Chicago, Illinois. It also describes the ...

Analysis of the human operator subsystems

NASA Technical Reports Server (NTRS)

Jones, Lynette A.; Hunter, Ian W.

1991-01-01

Except in low-bandwidth systems, knowledge of the human operator transfer function is essential for high-performance telerobotic systems. This information has usually been derived from detailed analyses of tracking performance, in which the human operator is considered as a complete system rather than as a summation of a number of subsystems, each of which influences the operator's output. Studies of one of these subsystems, the limb mechanics system, demonstrate that large parameter variations can occur that can have a profound effect on the stability of force-reflecting telerobot systems. An objective of this research was to decompose the performance of the human operator system in order to establish how the dynamics of each of the elements influence the operator's responses.

Jobs Analysis | Energy Analysis | NREL

Science.gov Websites

manufacturing analysis-focuses on jobs creation and economic output at the national, state, and community levels economic development and activity through investment in solar and wind projects. Featured Study In Economic construction period and 350 jobs annually during 20-year operation Total economic impact over 20-year life

Analysis of rosen piezoelectric transformers with a varying cross-section.

PubMed

Xue, H; Yang, J; Hu, Y

2008-07-01

We study the effects of a varying cross-section on the performance of Rosen piezoelectric transformers operating with length extensional modes of rods. A theoretical analysis is performed using an extended version of a one-dimensional model developed in a previous paper. Numerical results based on the theoretical analysis are presented.

Two dimensional eye tracking: Sampling rate of forcing function

NASA Technical Reports Server (NTRS)

Hornseth, J. P.; Monk, D. L.; Porterfield, J. L.; Mcmurry, R. L.

1978-01-01

A study was conducted to determine the minimum update rate of a forcing function display required for the operator to approximate the tracking performance obtained on a continuous display. In this study, frequency analysis was used to determine whether there was an associated change in the transfer function characteristics of the operator. It was expected that as the forcing function display update rate was reduced, from 120 to 15 samples per second, the operator's response to the high frequency components of the forcing function would show a decrease in gain, an increase in phase lag, and a decrease in coherence.

Impact of Operational Theater on Combat and Noncombat Trauma-Related Infections

PubMed Central

Tribble, David R.; Li, Ping; Warkentien, LCDR Tyler E.; Lloyd, Col Bradley A.; Schnaubelt, Maj Elizabeth R.; Ganesan, Anuradha; Bradley, William; Aggarwal, Deepak; Carson, M. Leigh; Weintrob, Amy C.; Murray, COL Clinton K.

2015-01-01

The Trauma Infectious Disease Outcomes Study began in June 2009 as combat operations were decreasing in Iraq and increasing in Afghanistan. Our analysis examines the rate of infections of wounded U.S military personnel from operational theaters in Iraq and Afghanistan admitted to Landstuhl Regional Medical Center between June 2009 and December 2013 and transferred to a participating U.S. hospital. Infection risk factors were examined in a multivariate logistic regression analysis (expressed as odds ratios [OR]; 95% confidence intervals [CI]). The study population includes 524 wounded military personnel from Iraq and 4766 from Afghanistan. The proportion of patients with at least one infection was 28% and 34% from the Iraq and Afghanistan theaters, respectively. The incidence density rate was 2.0 (per 100 person-days) for Iraq and 2.7 infections for Afghanistan. Independent risk factors included large-volume blood product transfusions (OR: 10.68; CI: 6.73–16.95), high injury severity score (OR: 2.48; CI: 1.81–3.41), and improvised explosive device injury mechanism (OR: 1.84; CI: 1.35–2.49). Operational theater (OR: 1.32; CI: 0.87–1.99) was not a risk factor. The difference in infection rates between operational theaters is primarily due to increased injury severity in Afghanistan from a higher proportion of blast-related trauma during the study period. PMID:27753561

Diaphragm and Lung Ultrasound to Predict Weaning Outcome: Systematic Review and Meta-Analysis.

PubMed

Llamas-Álvarez, Ana M; Tenza-Lozano, Eva M; Latour-Pérez, Jaime

2017-12-01

Deciding the optimal timing for extubation in patients who are mechanically ventilated can be challenging, and traditional weaning predictor tools are not very accurate. The aim of this systematic review and meta-analysis was to assess the accuracy of lung and diaphragm ultrasound for predicting weaning outcomes in critically ill adults. MEDLINE, the Cochrane Library, Web of Science, Scopus, LILACS, Teseo, Tesis Doctorales en Red, and OpenGrey were searched, and the bibliographies of relevant studies were reviewed. Two researchers independently selected studies that met the inclusion criteria and assessed study quality in accordance with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The summary receiver-operating characteristic curve and pooled diagnostic OR (DOR) were estimated by using a bivariate random effects analysis. Sources of heterogeneity were explored by using predefined subgroup analyses and bivariate meta-regression. Nineteen studies involving 1,071 people were included in the study. For diaphragm thickening fraction, the area under the summary receiver-operating characteristic curve was 0.87, and DOR was 21 (95% CI, 11-40). Regarding diaphragmatic excursion, pooled sensitivity was 75% (95% CI, 65-85); pooled specificity, 75% (95% CI, 60-85); and DOR, 10 (95% CI, 4-24). For lung ultrasound, the area under the summary receiver-operating characteristic curve was 0.77, and DOR was 38 (95% CI, 7-198). Based on bivariate meta-regression analysis, a significantly higher specificity for diaphragm thickening fraction and higher sensitivity for diaphragmatic excursion was detected in studies with applicability concerns. Lung and diaphragm ultrasound can help predict weaning outcome, but its accuracy may vary depending on the patient subpopulation. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Distinction between Externally vs. Internally Guided Decision-Making: Operational Differences, Meta-Analytical Comparisons and Their Theoretical Implications

PubMed Central

Nakao, Takashi; Ohira, Hideki; Northoff, Georg

2012-01-01

Most experimental studies of decision-making have specifically examined situations in which a single less-predictable correct answer exists (externally guided decision-making under uncertainty). Along with such externally guided decision-making, there are instances of decision-making in which no correct answer based on external circumstances is available for the subject (internally guided decision-making). Such decisions are usually made in the context of moral decision-making as well as in preference judgment, where the answer depends on the subject’s own, i.e., internal, preferences rather than on external, i.e., circumstantial, criteria. The neuronal and psychological mechanisms that allow guidance of decisions based on more internally oriented criteria in the absence of external ones remain unclear. This study was undertaken to compare decision-making of these two kinds empirically and theoretically. First, we reviewed studies of decision-making to clarify experimental–operational differences between externally guided and internally guided decision-making. Second, using multi-level kernel density analysis, a whole-brain-based quantitative meta-analysis of neuroimaging studies was performed. Our meta-analysis revealed that the neural network used predominantly for internally guided decision-making differs from that for externally guided decision-making under uncertainty. This result suggests that studying only externally guided decision-making under uncertainty is insufficient to account for decision-making processes in the brain. Finally, based on the review and results of the meta-analysis, we discuss the differences and relations between decision-making of these two types in terms of their operational, neuronal, and theoretical characteristics. PMID:22403525

A comparison of endoscopic localization error rate between operating surgeons and referring endoscopists in colorectal cancer.

PubMed

Azin, Arash; Saleh, Fady; Cleghorn, Michelle; Yuen, Andrew; Jackson, Timothy; Okrainec, Allan; Quereshy, Fayez A

2017-03-01

Colonoscopy for colorectal cancer (CRC) has a localization error rate as high as 21 %. Such errors can have substantial clinical consequences, particularly in laparoscopic surgery. The primary objective of this study was to compare accuracy of tumor localization at initial endoscopy performed by either the operating surgeon or non-operating referring endoscopist. All patients who underwent surgical resection for CRC at a large tertiary academic hospital between January 2006 and August 2014 were identified. The exposure of interest was the initial endoscopist: (1) surgeon who also performed the definitive operation (operating surgeon group); and (2) referring gastroenterologist or general surgeon (referring endoscopist group). The outcome measure was localization error, defined as a difference in at least one anatomic segment between initial endoscopy and final operative location. Multivariate logistic regression was used to explore the association between localization error rate and the initial endoscopist. A total of 557 patients were included in the study; 81 patients in the operating surgeon cohort and 476 patients in the referring endoscopist cohort. Initial diagnostic colonoscopy performed by the operating surgeon compared to referring endoscopist demonstrated statistically significant lower intraoperative localization error rate (1.2 vs. 9.0 %, P = 0.016); shorter mean time from endoscopy to surgery (52.3 vs. 76.4 days, P = 0.015); higher tattoo localization rate (32.1 vs. 21.0 %, P = 0.027); and lower preoperative repeat endoscopy rate (8.6 vs. 40.8 %, P < 0.001). Initial endoscopy performed by the operating surgeon was protective against localization error on both univariate analysis, OR 7.94 (95 % CI 1.08-58.52; P = 0.016), and multivariate analysis, OR 7.97 (95 % CI 1.07-59.38; P = 0.043). This study demonstrates that diagnostic colonoscopies performed by an operating surgeon are independently associated with a lower localization error rate. Further research exploring the factors influencing localization accuracy and why operating surgeons have lower error rates relative to non-operating endoscopists is necessary to understand differences in care.

Optimizing Biorefinery Design and Operations via Linear Programming Models

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

Talmadge, Michael; Batan, Liaw; Lamers, Patrick

The ability to assess and optimize economics of biomass resource utilization for the production of fuels, chemicals and power is essential for the ultimate success of a bioenergy industry. The team of authors, consisting of members from the National Renewable Energy Laboratory (NREL) and the Idaho National Laboratory (INL), has developed simple biorefinery linear programming (LP) models to enable the optimization of theoretical or existing biorefineries. The goal of this analysis is to demonstrate how such models can benefit the developing biorefining industry. It focuses on a theoretical multi-pathway, thermochemical biorefinery configuration and demonstrates how the biorefinery can use LPmore » models for operations planning and optimization in comparable ways to the petroleum refining industry. Using LP modeling tools developed under U.S. Department of Energy's Bioenergy Technologies Office (DOE-BETO) funded efforts, the authors investigate optimization challenges for the theoretical biorefineries such as (1) optimal feedstock slate based on available biomass and prices, (2) breakeven price analysis for available feedstocks, (3) impact analysis for changes in feedstock costs and product prices, (4) optimal biorefinery operations during unit shutdowns / turnarounds, and (5) incentives for increased processing capacity. These biorefinery examples are comparable to crude oil purchasing and operational optimization studies that petroleum refiners perform routinely using LPs and other optimization models. It is important to note that the analyses presented in this article are strictly theoretical and they are not based on current energy market prices. The pricing structure assigned for this demonstrative analysis is consistent with $4 per gallon gasoline, which clearly assumes an economic environment that would favor the construction and operation of biorefineries. The analysis approach and examples provide valuable insights into the usefulness of analysis tools for maximizing the potential benefits of biomass utilization for production of fuels, chemicals and power.« less

Environmental quality of the operating theaters in Campania Region: long lasting monitoring results.

PubMed

Triassi, M; Novi, C; Nardone, A; Russo, I; Montuori, P

2015-01-01

The health risk level in the operating theaters is directly correlated to the safety level offered by the healthcare facilities. This is the reason why the national Authorities released several regulations in order to monitor better environmental conditions of the operating theaters, to prevent occupational injuries and disease and to optimize working conditions. For the monitoring of environmental quality of the operating theaters following parameters are considered: quantity of supplied gases, anesthetics concentration, operating theatres volume measurement, air change rate, air conditioning system and air filtration. The objective is to minimize the risks in the operating theaters and to provide the optimal environmental working conditions. This paper reports the environmental conditions of operating rooms performed for several years in the public hospitals of the Campania Region. Investigation of environmental conditions of 162 operating theaters in Campania Region from January 2012 till July 2014 was conducted. Monitoring and analysis of physical and chemical parameters was done. The analysis of the results has been made considering specific standards suggested by national and international regulations. The study showed that 75% of the operating theaters presented normal values for microclimatic monitoring, while the 25% of the operating theaters had at least one parameter outside the limits. The monitoring of the anesthetics gases showed that in 9% of measurements of nitrous oxides and 4% of measurements of halogenated was not within the normal values.

Orbit transfer rocket engine technology program. Phase 2: Advanced engine study

NASA Technical Reports Server (NTRS)

Erickson, C.; Martinez, A.; Hines, B.

1987-01-01

In Phase 2 of the Advanced Engine Study, the Failure Modes and Effects Analysis (FMEA) maintenance-driven engine design, preliminary maintenance plan, and concept for space operable disconnects generated in Phase 1 were further developed. Based on the results of the vehicle contractors Orbit Transfer Vehicle (OTV) Concept Definition and System Analysis Phase A studies, minor revisions to the engine design were made. Additional refinements in the engine design were identified through further engine concept studies. These included an updated engine balance incorporating experimental heat transfer data from the Enhanced Heat Load Thrust Chamber Study and a Rao optimum nozzle contour. The preliminary maintenance plan of Phase 1 was further developed through additional studies. These included a compilation of critical component lives and life limiters and a review of the Space Shuttle Main Engine (SSME) operations and maintenance manual in order to begin outlining the overall maintenance procedures for the Orbit Transfer Vehicle Engine and identifying technology requirements for streamlining space-based operations. Phase 2 efforts also provided further definition to the advanced fluid coupling devices including the selection and preliminary design of a preferred concept and a preliminary test plan for its further development.

Mapping Copper and Lead Concentrations at Abandoned Mine Areas Using Element Analysis Data from ICP–AES and Portable XRF Instruments: A Comparative Study

PubMed Central

Lee, Hyeongyu; Choi, Yosoon; Suh, Jangwon; Lee, Seung-Ho

2016-01-01

Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both operating and abandoned mining areas. Many studies have been conducted worldwide to explore the spatial variation of PTEs and to create soil contamination maps using geostatistical methods. However, they generally depend only on inductively coupled plasma atomic emission spectrometry (ICP–AES) analysis data, therefore such studies are limited by insufficient input data owing to the disadvantages of ICP–AES analysis such as its costly operation and lengthy period required for analysis. To overcome this limitation, this study used both ICP–AES and portable X-ray fluorescence (PXRF) analysis data, with relatively low accuracy, for mapping copper and lead concentrations at a section of the Busan abandoned mine in Korea and compared the prediction performances of four different approaches: the application of ordinary kriging to ICP–AES analysis data, PXRF analysis data, both ICP–AES and transformed PXRF analysis data by considering the correlation between the ICP–AES and PXRF analysis data, and co-kriging to both the ICP–AES (primary variable) and PXRF analysis data (secondary variable). Their results were compared using an independent validation data set. The results obtained in this case study showed that the application of ordinary kriging to both ICP–AES and transformed PXRF analysis data is the most accurate approach when considers the spatial distribution of copper and lead contaminants in the soil and the estimation errors at 11 sampling points for validation. Therefore, when generating soil contamination maps for an abandoned mine, it is beneficial to use the proposed approach that incorporates the advantageous aspects of both ICP–AES and PXRF analysis data. PMID:27043594

Mapping Copper and Lead Concentrations at Abandoned Mine Areas Using Element Analysis Data from ICP-AES and Portable XRF Instruments: A Comparative Study.

PubMed

Lee, Hyeongyu; Choi, Yosoon; Suh, Jangwon; Lee, Seung-Ho

2016-03-30

Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both operating and abandoned mining areas. Many studies have been conducted worldwide to explore the spatial variation of PTEs and to create soil contamination maps using geostatistical methods. However, they generally depend only on inductively coupled plasma atomic emission spectrometry (ICP-AES) analysis data, therefore such studies are limited by insufficient input data owing to the disadvantages of ICP-AES analysis such as its costly operation and lengthy period required for analysis. To overcome this limitation, this study used both ICP-AES and portable X-ray fluorescence (PXRF) analysis data, with relatively low accuracy, for mapping copper and lead concentrations at a section of the Busan abandoned mine in Korea and compared the prediction performances of four different approaches: the application of ordinary kriging to ICP-AES analysis data, PXRF analysis data, both ICP-AES and transformed PXRF analysis data by considering the correlation between the ICP-AES and PXRF analysis data, and co-kriging to both the ICP-AES (primary variable) and PXRF analysis data (secondary variable). Their results were compared using an independent validation data set. The results obtained in this case study showed that the application of ordinary kriging to both ICP-AES and transformed PXRF analysis data is the most accurate approach when considers the spatial distribution of copper and lead contaminants in the soil and the estimation errors at 11 sampling points for validation. Therefore, when generating soil contamination maps for an abandoned mine, it is beneficial to use the proposed approach that incorporates the advantageous aspects of both ICP-AES and PXRF analysis data.

Analysis of failure and maintenance experiences of motor operated valves in a Finnish nuclear power plant

NASA Astrophysics Data System (ADS)

Simola, Kaisa; Laakso, Kari

1992-01-01

Eight years of operating experiences of 104 motor operated closing valves in different safety systems in nuclear power units were analyzed in a systematic way. The qualitative methods used were Failure Mode and Effect Analysis (FMEA) and Maintenance Effects and Criticality Analysis (MECA). These reliability engineering methods are commonly used in the design stage of equipment. The successful application of these methods for analysis and utilization of operating experiences was demonstrated.

Application of Hierarchical Goal Analysis to the Halifax Class Frigate Operations Room: A Case Study

DTIC Science & Technology

2007-11-01

actuelle en fonction de son niveau de soutien pour ces diverses dépendances. Les auteurs prévoient que la même méthode peut être utilisée pour décrire...analysis. The focus of this paper is on the practice rather than the theory of HGA. Therefore, the next section contains only a brief summary of the...is based on Perceptual Control Theory [17], which posits that humans operate as perceptually driven, goal referenced, feedback systems, in that all

Advancing the Fork detector for quantitative spent nuclear fuel verification

DOE PAGES

Vaccaro, S.; Gauld, I. C.; Hu, J.; ...

2018-01-31

The Fork detector is widely used by the safeguards inspectorate of the European Atomic Energy Community (EURATOM) and the International Atomic Energy Agency (IAEA) to verify spent nuclear fuel. Fork measurements are routinely performed for safeguards prior to dry storage cask loading. Additionally, spent fuel verification will be required at the facilities where encapsulation is performed for acceptance in the final repositories planned in Sweden and Finland. The use of the Fork detector as a quantitative instrument has not been prevalent due to the complexity of correlating the measured neutron and gamma ray signals with fuel inventories and operator declarations.more » A spent fuel data analysis module based on the ORIGEN burnup code was recently implemented to provide automated real-time analysis of Fork detector data. This module allows quantitative predictions of expected neutron count rates and gamma units as measured by the Fork detectors using safeguards declarations and available reactor operating data. This study describes field testing of the Fork data analysis module using data acquired from 339 assemblies measured during routine dry cask loading inspection campaigns in Europe. Assemblies include both uranium oxide and mixed-oxide fuel assemblies. More recent measurements of 50 spent fuel assemblies at the Swedish Central Interim Storage Facility for Spent Nuclear Fuel are also analyzed. An evaluation of uncertainties in the Fork measurement data is performed to quantify the ability of the data analysis module to verify operator declarations and to develop quantitative go/no-go criteria for safeguards verification measurements during cask loading or encapsulation operations. The goal of this approach is to provide safeguards inspectors with reliable real-time data analysis tools to rapidly identify discrepancies in operator declarations and to detect potential partial defects in spent fuel assemblies with improved reliability and minimal false positive alarms. Finally, the results are summarized, and sources and magnitudes of uncertainties are identified, and the impact of analysis uncertainties on the ability to confirm operator declarations is quantified.« less

Advancing the Fork detector for quantitative spent nuclear fuel verification

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

Vaccaro, S.; Gauld, I. C.; Hu, J.

The Fork detector is widely used by the safeguards inspectorate of the European Atomic Energy Community (EURATOM) and the International Atomic Energy Agency (IAEA) to verify spent nuclear fuel. Fork measurements are routinely performed for safeguards prior to dry storage cask loading. Additionally, spent fuel verification will be required at the facilities where encapsulation is performed for acceptance in the final repositories planned in Sweden and Finland. The use of the Fork detector as a quantitative instrument has not been prevalent due to the complexity of correlating the measured neutron and gamma ray signals with fuel inventories and operator declarations.more » A spent fuel data analysis module based on the ORIGEN burnup code was recently implemented to provide automated real-time analysis of Fork detector data. This module allows quantitative predictions of expected neutron count rates and gamma units as measured by the Fork detectors using safeguards declarations and available reactor operating data. This study describes field testing of the Fork data analysis module using data acquired from 339 assemblies measured during routine dry cask loading inspection campaigns in Europe. Assemblies include both uranium oxide and mixed-oxide fuel assemblies. More recent measurements of 50 spent fuel assemblies at the Swedish Central Interim Storage Facility for Spent Nuclear Fuel are also analyzed. An evaluation of uncertainties in the Fork measurement data is performed to quantify the ability of the data analysis module to verify operator declarations and to develop quantitative go/no-go criteria for safeguards verification measurements during cask loading or encapsulation operations. The goal of this approach is to provide safeguards inspectors with reliable real-time data analysis tools to rapidly identify discrepancies in operator declarations and to detect potential partial defects in spent fuel assemblies with improved reliability and minimal false positive alarms. Finally, the results are summarized, and sources and magnitudes of uncertainties are identified, and the impact of analysis uncertainties on the ability to confirm operator declarations is quantified.« less

Performation Metrics Development Analysis for Information and Communications Technology Outsourcing: A Case Study

ERIC Educational Resources Information Center

Travis, James L., III

2014-01-01

This study investigated how and to what extent the development and use of the OV-5a operational architecture decomposition tree (OADT) from the Department of Defense (DoD) Architecture Framework (DoDAF) affects requirements analysis with respect to complete performance metrics for performance-based services acquisition of ICT under rigid…

Space shuttle navigation analysis

NASA Technical Reports Server (NTRS)

Jones, H. L.; Luders, G.; Matchett, G. A.; Sciabarrasi, J. E.

1976-01-01

A detailed analysis of space shuttle navigation for each of the major mission phases is presented. A covariance analysis program for prelaunch IMU calibration and alignment for the orbital flight tests (OFT) is described, and a partial error budget is presented. The ascent, orbital operations and deorbit maneuver study considered GPS-aided inertial navigation in the Phase III GPS (1984+) time frame. The entry and landing study evaluated navigation performance for the OFT baseline system. Detailed error budgets and sensitivity analyses are provided for both the ascent and entry studies.

Cell module and fuel conditioner development

NASA Technical Reports Server (NTRS)

Feret, J. M.

1982-01-01

The efforts performed to develop a phosphoric acid fuel cell (PAFC) stack design having a 10 kW power rating for operation at higher than atmospheric pressure based on the existing Mark II design configuration are described. The work involves: (1) Performance of pertinent functional analysis, trade studies and thermodynamic cycle analysis for requirements definition and system operating parameter selection purposes, (2) characterization of fuel cell materials and components, and performance testing and evaluation of the repeating electrode components, (3) establishment of the state-of-the-art manufacturing technology for all fuel cell components at Westinghouse and the fabrication of short stacks of various sites, and (4) development of a 10 kW PAFC stack design for higher pressure operation utilizing the top down systems engineering approach.

Evaluation of Graph Pattern Matching Workloads in Graph Analysis Systems

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

Hong, Seokyong; Lee, Sangkeun; Lim, Seung-Hwan

2016-01-01

Graph analysis has emerged as a powerful method for data scientists to represent, integrate, query, and explore heterogeneous data sources. As a result, graph data management and mining became a popular area of research, and led to the development of plethora of systems in recent years. Unfortunately, the number of emerging graph analysis systems and the wide range of applications, coupled with a lack of apples-to-apples comparisons, make it difficult to understand the trade-offs between different systems and the graph operations for which they are designed. A fair comparison of these systems is a challenging task for the following reasons:more » multiple data models, non-standardized serialization formats, various query interfaces to users, and diverse environments they operate in. To address these key challenges, in this paper we present a new benchmark suite by extending the Lehigh University Benchmark (LUBM) to cover the most common capabilities of various graph analysis systems. We provide the design process of the benchmark, which generalizes the workflow for data scientists to conduct the desired graph analysis on different graph analysis systems. Equipped with this extended benchmark suite, we present performance comparison for nine subgraph pattern retrieval operations over six graph analysis systems, namely NetworkX, Neo4j, Jena, Titan, GraphX, and uRiKA. Through the proposed benchmark suite, this study reveals both quantitative and qualitative findings in (1) implications in loading data into each system; (2) challenges in describing graph patterns for each query interface; and (3) different sensitivity of each system to query selectivity. We envision that this study will pave the road for: (i) data scientists to select the suitable graph analysis systems, and (ii) data management system designers to advance graph analysis systems.« less

Motor current signature analysis method for diagnosing motor operated devices

DOEpatents

Haynes, Howard D.; Eissenberg, David M.

1990-01-01

A motor current noise signature analysis method and apparatus for remotely monitoring the operating characteristics of an electric motor-operated device such as a motor-operated valve. Frequency domain signal analysis techniques are applied to a conditioned motor current signal to distinctly identify various operating parameters of the motor driven device from the motor current signature. The signature may be recorded and compared with subsequent signatures to detect operating abnormalities and degradation of the device. This diagnostic method does not require special equipment to be installed on the motor-operated device, and the current sensing may be performed at remote control locations, e.g., where the motor-operated devices are used in accessible or hostile environments.

Overview of aerothermodynamic loads definition study

NASA Technical Reports Server (NTRS)

Gaugler, Raymond E.

1991-01-01

The objective of the Aerothermodynamic Loads Definition Study is to develop methods of accurately predicting the operating environment in advanced Earth-to-Orbit (ETO) propulsion systems, such as the Space Shuttle Main Engine (SSME) powerhead. Development of time averaged and time dependent three dimensional viscous computer codes as well as experimental verification and engine diagnostic testing are considered to be essential in achieving that objective. Time-averaged, nonsteady, and transient operating loads must all be well defined in order to accurately predict powerhead life. Described here is work in unsteady heat flow analysis, improved modeling of preburner flow, turbulence modeling for turbomachinery, computation of three dimensional flow with heat transfer, and unsteady viscous multi-blade row turbine analysis.

A risk analysis of winter navigation in Finnish sea areas.

PubMed

Valdez Banda, Osiris A; Goerlandt, Floris; Montewka, Jakub; Kujala, Pentti

2015-06-01

Winter navigation is a complex but common operation in north-European sea areas. In Finnish waters, the smooth flow of maritime traffic and safety of vessel navigation during the winter period are managed through the Finnish-Swedish winter navigation system (FSWNS). This article focuses on accident risks in winter navigation operations, beginning with a brief outline of the FSWNS. The study analyses a hazard identification model of winter navigation and reviews accident data extracted from four winter periods. These are adopted as a basis for visualizing the risks in winter navigation operations. The results reveal that experts consider ship independent navigation in ice conditions the most complex navigational operation, which is confirmed by accident data analysis showing that the operation constitutes the type of navigation with the highest number of accidents reported. The severity of the accidents during winter navigation is mainly categorized as less serious. Collision is the most typical accident in ice navigation and general cargo the type of vessel most frequently involved in these accidents. Consolidated ice, ice ridges and ice thickness between 15 and 40cm represent the most common ice conditions in which accidents occur. Thus, the analysis presented in this article establishes the key elements for identifying the operation types which would benefit most from further safety engineering and safety or risk management development. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of a protocol to optimize electric power consumption and life cycle environmental impacts for operation of wastewater treatment plant.

PubMed

Piao, Wenhua; Kim, Changwon; Cho, Sunja; Kim, Hyosoo; Kim, Minsoo; Kim, Yejin

2016-12-01

In wastewater treatment plants (WWTPs), the portion of operating costs related to electric power consumption is increasing. If the electric power consumption decreased, however, it would be difficult to comply with the effluent water quality requirements. A protocol was proposed to minimize the environmental impacts as well as to optimize the electric power consumption under the conditions needed to meet the effluent water quality standards in this study. This protocol was comprised of six phases of procedure and was tested using operating data from S-WWTP to prove its applicability. The 11 major operating variables were categorized into three groups using principal component analysis and K-mean cluster analysis. Life cycle assessment (LCA) was conducted for each group to deduce the optimal operating conditions for each operating state. Then, employing mathematical modeling, six improvement plans to reduce electric power consumption were deduced. The electric power consumptions for suggested plans were estimated using an artificial neural network. This was followed by a second round of LCA conducted on the plans. As a result, a set of optimized improvement plans were derived for each group that were able to optimize the electric power consumption and life cycle environmental impact, at the same time. Based on these test results, the WWTP operating management protocol presented in this study is deemed able to suggest optimal operating conditions under which power consumption can be optimized with minimal life cycle environmental impact, while allowing the plant to meet water quality requirements.

Space Tug Docking Study. Volume 1: Executive Summary

NASA Technical Reports Server (NTRS)

1976-01-01

Results of a detailed systems analysis of the entire rendezvous and docking operation to be performed by the all-up space tug are presented. Specific areas investigated include: generating of operational requirements and a data base of candidate operational techniques and subsystem mechanizations; selection and ranking of integrated system designs capable of meeting the requirements generated; and definition of this simulation/demonstration program required to select and prove the most effective manual, autonomous, and hybrid rendezvous and docking systems.

Treatment integrity of school-based interventions with children in the journal of applied behavior analysis 1991-2005.

PubMed

McIntyre, Laura Lee; Gresham, Frank M; DiGennaro, Florence D; Reed, Derek D

2007-01-01

We reviewed all school-based experimental studies with individuals 0 to 18 years published in the Journal of Applied Behavior Analysis (JABA) between 1991 and 2005. A total of 142 articles (152 studies) that met review criteria were included. Nearly all (95%) of these experiments provided an operational definition of the independent variable, but only 30% of the studies provided treatment integrity data. Nearly half of studies (45%) were judged to be at high risk for treatment inaccuracies. Treatment integrity data were more likely to be included in studies that used teachers, multiple treatment agents, or both. Although there was a substantial increase in reporting operational definitions of independent variables, results suggest that there was only a modest improvement in reported integrity over the past 30 years of JABA studies. Recommendations for research and practice are discussed.

[Non-operative treatment for severe forms of infantile idiopathic scoliosis].

PubMed

Trobisch, P D; Samdani, A; O'Neil, C; Betz, R; Cahill, P

2012-02-01

Infantile idiopathic scoliosis (IIS) is a rare orthopaedic condition. Braces and casts are popular options in the treatment of IIS but there is a paucity of studies commenting on the outcome of non-operative treatment. The purpose of this study was to analyse failure and success after non-operative treatment for severe forms of IIS. We retrospectively reviewed the data of all children who had been treated for IIS between 2003 and 2009 at a single institution. After calculating the failure and success rates, we additionally performed a risk factor analysis for patients who failed non-operative treatment. Chi (2) and T tests were used for statistical analysis with significance set at p < 0.05. 25 children with an average age of 11 months and an Cobb angle of 46 degrees at presentation were analysed. Seven (28 %) patients were considered as having failed non-operative treatment after an average follow-up of 28 months. The pretreatment Cobb angle was identified as single significant risk factor for failure (55 versus 42) while neither age, gender, nor RVAD seem to influence the outcome. In children who were considered as successfully treated, the Cobb angle decreased from 42 to 18 degrees. Non-operative treatment for IIS is successful in 3 out of 4 patients. © Georg Thieme Verlag KG Stuttgart · New York.

Contingency Analysis Post-Processing With Advanced Computing and Visualization

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

Chen, Yousu; Glaesemann, Kurt; Fitzhenry, Erin

Contingency analysis is a critical function widely used in energy management systems to assess the impact of power system component failures. Its outputs are important for power system operation for improved situational awareness, power system planning studies, and power market operations. With the increased complexity of power system modeling and simulation caused by increased energy production and demand, the penetration of renewable energy and fast deployment of smart grid devices, and the trend of operating grids closer to their capacity for better efficiency, more and more contingencies must be executed and analyzed quickly in order to ensure grid reliability andmore » accuracy for the power market. Currently, many researchers have proposed different techniques to accelerate the computational speed of contingency analysis, but not much work has been published on how to post-process the large amount of contingency outputs quickly. This paper proposes a parallel post-processing function that can analyze contingency analysis outputs faster and display them in a web-based visualization tool to help power engineers improve their work efficiency by fast information digestion. Case studies using an ESCA-60 bus system and a WECC planning system are presented to demonstrate the functionality of the parallel post-processing technique and the web-based visualization tool.« less

Use of wind data in global modelling

NASA Technical Reports Server (NTRS)

Pailleux, J.

1985-01-01

The European Centre for Medium Range Weather Forecasts (ECMWF) is producing operational global analyses every 6 hours and operational global forecasts every day from the 12Z analysis. How the wind data are used in the ECMWF golbal analysis is described. For each current wind observing system, its ability to provide initial conditions for the forecast model is discussed as well as its weaknesses. An assessment of the impact of each individual system on the quality of the analysis and the forecast is given each time it is possible. Sometimes the deficiencies which are pointed out are related not only to the observing system itself but also to the optimum interpolation (OI) analysis scheme; then some improvements are generally possible through ad hoc modifications of the analysis scheme and especially tunings of the structure functions. Examples are given. The future observing network over the North Atlantic is examined. Several countries, coordinated by WMO, are working to set up an 'Operational WWW System Evaluation' (OWSE), in order to evaluate the operational aspects of the deployment of new systems (ASDAR, ASAP). Most of the new systems are expected to be deployed before January 1987, and in order to make the best use of the available resources during the deployment phase, some network studies are carried out at the present time, by using simulated data for ASDAR and ASAP systems. They are summarized.

Frequency of distracting tasks people do while driving : an analysis of the ACAS FOT data.

DOT National Transportation Integrated Search

2007-06-01

This report describes further analysis of data from the advanced collision avoidance system (ACAS) field operational test, a naturalistic driving study. To determine how distracted and nondistracted driving differ, a stratified sample of 2,914 video ...

Fault Tree Analysis as a Planning and Management Tool: A Case Study

ERIC Educational Resources Information Center

Witkin, Belle Ruth

1977-01-01

Fault Tree Analysis is an operations research technique used to analyse the most probable modes of failure in a system, in order to redesign or monitor the system more closely in order to increase its likelihood of success. (Author)

Ulipristal acetate for pre-operative treatment of moderate-to-severe uterine fibroids in women of reproductive age in The Netherlands: cost minimization analysis and budget impact analysis.

PubMed

Zakiyah, N; van Asselt, A D I; Postma, M J

2017-03-01

Ulipristal acetate has been found to be non-inferior to other pre-operative treatments of uterine fibroids, particularly leuprolide. The objective of this study was to assess the pharmacoeconomic profile of ulipristal acetate compared to leuprolide for the pre-operative treatment of moderate-to-severe uterine fibroids in women of reproductive age in The Netherlands. The analysis was performed and applied within the framework of the ulipristal acetate submission for reimbursement in 2012. A decision model was developed to compare the total costs of ulipristal acetate compared to leuprolide, the standard care in The Netherlands. The target population of this study corresponded to the type of patients included in the PEARL II clinical trial; i.e. women of reproductive age requiring pre-operative treatment for uterine fibroids. Sensitivity analysis was implemented to assess uncertainties. Data regarding costs, effects, and other input parameters were obtained from relevant published literatures, the Dutch Healthcare Insurance Board, and expert opinion obtained by means of a panel of experts from several medical centers in The Netherlands. In The Netherlands, the total costs of ulipristal acetate and leuprolide were estimated at €4,216,027 and €4,218,095, respectively. The annual savings of ulipristal acetate were, therefore, estimated at €2,068. The major driver of this cost difference was the cost of administration for leuprolide. Sensitivity analyses showed that ulipristal acetate mostly remained cost-saving over a range of assumptions. The budget impact analysis indicated that the introduction of ulipristal acetate was estimated to result in cost savings in the first 3 years following the introduction. The results of this study were used in the decision on reimbursement of ulipristal acetate according to the Dutch Reference Pricing system in 2012. Ulipristal acetate was cost saving compared to leuprolide and has the potential to provide substantial savings on the healthcare budget in The Netherlands.

Receiver operating characteristic analysis. Application to the study of quantum fluctuation effects in optic nerve of Rana pipiens

PubMed Central

1975-01-01

Receiver operating characteristic (ROC) analysis of nerve messages is described. The hypothesis that quantum fluctuations provide the only limit to the ability of frog ganglion cells to signal luminance change information is examined using ROC analysis. In the context of ROC analysis, the quantum fluctuation hypothesis predicts (a) the detectability of a luminance change signal should rise proportionally to the size of the change, (b) detectability should decrease as the square root of background, an implication of which is the deVries-Rose law, and (c) ROC curves should exhibit a shape particular to underlying Poisson distributions. Each of these predictions is confirmed for the responses of dimming ganglion cells to brief luminance decrements at scotopic levels, but none could have been tested using classical nerve message analysis procedures. PMID:172597

Tactical Integration of Conventional and Special Operations Forces in Training for a Complex World

DTIC Science & Technology

2016-05-26

the researcher has formulated for analysis of the single case study of OEF. Operation Enduring Freedom was selected for its contemporary relevance and...5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) Major Darren Riley 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER School of Advanced Military Studies 320 Gibson Avenue

Radiology operations: what you don't know could be costing you millions.

PubMed

Joffe, Sam; Drew, Donna; Bansal, Manju; Hase, Michael

2007-01-01

Rapid growth in advanced imaging procedures has left hospital radiology departments struggling to keep up with demand, resulting in loss of patients to facilities that can offer service more quickly. While the departments appear to be working at full capacity, an operational analysis of over 400 hospital radiology departments in the US by GE Healthcare has determined that, paradoxically, many departments are in fact underutilized and operating for below their potential capacity. While CT cycle time in hospitals that were studied averaged 35 minutes, top performing hospitals operated the same equipment at a cycle time of 15 minutes, yielding approximately double the throughput volume. Factors leading to suboptimal performance include accounting metrics that mask true performance, leadership focus on capital investment rather than operations, under staffing, under scheduling, poorly aligned incentives, a fragmented view of operations, lack of awareness of latent opportunities, and lack of sufficient skills and processes to implement improvements. The study showed how modest investments in radiology operations can dramatically improve access to services and profitability.

Well-to-Wheels Analysis of Advanced Fuel/Vehicle Systems: A North American Study of Energy Use, Greenhouse Gas Emissions, and Criteria Pollutant Emissions

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

Brinkman, Norman; Wang, Michael; Weber, Trudy

An accurate assessment of future fuel/propulsion system options requires a complete vehicle fuel-cycle analysis, commonly called a well-to-wheels (WTW) analysis. This WTW study analyzes energy use and emissions associated with fuel production (or well-to-tank [WTT]) activities and energy use and emissions associated with vehicle operation (or tank-to-wheels [TTW]) activities.

Strategic Anslysis of Two Joint Contingency Operations: Lebanon 1958 and Dominican Republic 1965

DTIC Science & Technology

1989-01-01

political aims in Lebanon 1958 and the Dominican Republic 1965. The study uses the Strategic Analysis Model, developed at the Command and General Staff...employment and be followed by political negotiations with participation by all factions. U UNCLASS IFIED STRATEGIC ANALYSIS OF TWO JOINT CONTINGENCY...United States use of military power to achieve political aims in Lebanon 1958 and the Dominican Republic 1965. The study uses the Strategic Analysis

Kennedy Space Center Orion Processing Team Planning for Ground Operations

NASA Technical Reports Server (NTRS)

Letchworth, Gary; Schlierf, Roland

2011-01-01

Topics in this presentation are: Constellation Ares I/Orion/Ground Ops Elements Orion Ground Operations Flow Orion Operations Planning Process and Toolset Overview, including: 1 Orion Concept of Operations by Phase 2 Ops Analysis Capabilities Overview 3 Operations Planning Evolution 4 Functional Flow Block Diagrams 5 Operations Timeline Development 6 Discrete Event Simulation (DES) Modeling 7 Ground Operations Planning Document Database (GOPDb) Using Operations Planning Tools for Operability Improvements includes: 1 Kaizen/Lean Events 2 Mockups 3 Human Factors Analysis

Rotary Ni-Ti profile systems for preparing curved canals in resin blocks: influence of operator on instrument breakage.

PubMed

Mandel, E; Adib-Yazdi, M; Benhamou, L M; Lachkar, T; Mesgouez, C; Sobel, M

1999-11-01

The aim of this study was to determine the incidence of fracture of ProFile 0.4 and 0.6 taper Series 29 nickel-titanium instruments with respect to operator experience. A total of 125 simulated root canals in resin blocks with the same geometrical shape in terms of angle and radius of curvature and coronal and apical orifice diameter were used. Five operators prepared all the specimens using an identical step-down instrument sequence, each one preparing 25 canals. The operators included two endodontists and three general practitioners. Statistical data concerning the incidence of instrument failure was compiled using Statlab and Fisher's partial least square difference analysis of variance. A total of 21 (16.8%) instruments fractured, all had 0.04 tapers. Nine size 25 instruments failed, 9 size 20 instruments failed and 3 size 15. During the study, the Binary Tree analysis of instrument failure revealed two operator populations belonging to two different study periods. The first period, which represented the first 13 root canal preparations, was called the 'learning period', and the second period, which represented the next 12 sample preparations, was called the 'application period'. A greater number of instruments failed during the first period than during the second. In the 'learning period', both groups of operators learned the same way. In the 'application period', two groups could be distinguished; the first group consisted of a general practitioner who produced worse results, and the second group consisted of the other four operators. The results indicate the necessity of mastering this rotary canal preparation technique, and the importance of improving competence through learning and experience.

Manual rotation to decrease operative delivery in posterior or transverse positions.

PubMed

Le Ray, Camille; Deneux-Tharaux, Catherine; Khireddine, Imane; Dreyfus, Michel; Vardon, Delphine; Goffinet, François

2013-09-01

To assess the effect of a policy of manual rotation on the mode of delivery of fetuses in posterior or transverse positions at full dilatation. This was a prospective study to compare two policies of management for posterior and transverse positions in two different hospitals (Hospital 1: no manual rotation and Hospital 2: manual rotation). We used univariable and multivariable analyses to study the association between the management policy for posterior and transverse positions at full dilatation in these hospitals and maternal and neonatal outcomes. The principal end point was operative delivery (ie, cesarean or instrumental vaginal delivery). All factors associated with the risk of operative delivery in the univariable analysis (P<.1) were included in the logistic regression models. We then specifically studied whether manual rotation was independently associated with a reduction in operative deliveries. The rate of posterior or transverse positions at full dilatation was 15.9% (n=111) in Hospital 1 and 15.3% (n=220) in Hospital 2 (P=.75). Of the 172 attempts of manual rotation in Hospital 2, 155 (90.1%) were successful. The rate of operative delivery was significantly lower in Hospital 2, which performed manual rotations (23.2% compared with 38.7% in Hospital 1, adjusted odds ratio [OR] 0.52, 95% confidence interval [CI] 0.28-0.95). After multivariable analysis, manual rotation remained significantly associated with a reduction in the risk of operative delivery (adjusted OR 0.45, 95% CI 0.25-0.85). Five-minute Apgar score and arterial pH at birth were similar in the two hospitals. For fetuses in posterior or transverse positions at full dilatation, a strategy of manual rotation is associated with a reduction in the rate of operative delivery. III.

Analysis of the embodied and operational energy: Study of a suburban house in Athens, Greece

NASA Astrophysics Data System (ADS)

Ghiata, Maria

Operational energy can establish how successful a building is, in terms of environmentally 'considerate' design. Though embodied energy of construction materials also comprises an important indicator of the environmental impact of the material, the construction industry does not really promote it as such. This report enhances the significance of embodied energy and its relationship to operational energy (energy in use). Since buildings are becoming less energy demanding, operational energy will be decreasing, so that embodied energy will be gaining ground in the attempt to protect the environment. By the use of an 'environmentally friendly' house as a case study, it was proven that, though changes of the wall, floor, and insulation materials can take place, the operational energy does not change. What is greatly affected is the embodied energy of these construction materials.

The Impact of Back-Sputtered Carbon on the Accelerator Grid Wear Rates of the NEXT and NSTAR Ion Thrusters

NASA Technical Reports Server (NTRS)

Soulas, George C.

2013-01-01

A study was conducted to quantify the impact of back-sputtered carbon on the downstream accelerator grid erosion rates of the NEXT (NASA's Evolutionary Xenon Thruster) Long Duration Test (LDT1). A similar analysis that was conducted for the NSTAR (NASA's Solar Electric Propulsion Technology Applications Readiness Program) Life Demonstration Test (LDT2) was used as a foundation for the analysis developed herein. A new carbon surface coverage model was developed that accounted for multiple carbon adlayers before complete surface coverage is achieved. The resulting model requires knowledge of more model inputs, so they were conservatively estimated using the results of past thin film sputtering studies and particle reflection predictions. In addition, accelerator current densities across the grid were rigorously determined using an ion optics code to determine accelerator current distributions and an algorithm to determine beam current densities along a grid using downstream measurements. The improved analysis was applied to the NSTAR test results for evaluation. The improved analysis demonstrated that the impact of back-sputtered carbon on pit and groove wear rate for the NSTAR LDT2 was negligible throughout most of eroded grid radius. The improved analysis also predicted the accelerator current density for transition from net erosion to net deposition considerably more accurately than the original analysis. The improved analysis was used to estimate the impact of back-sputtered carbon on the accelerator grid pit and groove wear rate of the NEXT Long Duration Test (LDT1). Unlike the NSTAR analysis, the NEXT analysis was more challenging because the thruster was operated for extended durations at various operating conditions and was unavailable for measurements because the test is ongoing. As a result, the NEXT LDT1 estimates presented herein are considered preliminary until the results of future posttest analyses are incorporated. The worst-case impact of carbon back-sputtering was determined to be the full power operating condition, but the maximum impact of back-sputtered carbon was only a four percent reduction in wear rate. As a result, back-sputtered carbon is estimated to have an insignificant impact on the first failure mode of the NEXT LDT at all operating conditions.

Repeatability of diagnostic ultrasonography in the assessment of the equine superficial digital flexor tendon.

PubMed

Pickersgill, C H; Marr, C M; Reid, S W

2001-01-01

A quantitative investigation of the variation that can occur during the course of ultrasonography of the equine superficial digital flexor tendons (SDFT) was undertaken. The aim of this investigation was to use an objective measure, namely the measurement of CSA, to quantify the variability occurring during the course of the ultrasonographic assessment of the equine SDFT. The effects of 3 variables on the CSA measurements were determined. 1) Image acquisition operator (IAc): two different operators undertaking the ultrasonographic examination; 2) image analysis operator (IAn): two different operators undertaking the calculation of CSA values from previously stored images; and 3) analytical equipment (used during CSA measurement) (IEq): the use of 2 different sets of equipment during calculation of CSA values. Tendon cross-sectional area (CSA) measurements were used as the comparative variable of 3 potential sources: interoperator, during image acquisition; interoperator, during CSA measurement; and intraoperator, when using different analytical equipment. Two operators obtained transverse ultrasonographic images from the forelimb SDFTs of 16 National Hunt (NH) Thoroughbred (TB) racehorses, each undertaking analysis of their own and the other operator's images. One operator undertook analysis of their images using 2 sets of equipment. There was no statistically significant difference in the results obtained when different operators undertook image acquisition (P>0.05). At all but the most distal level, there was no significant difference when different equipment was used during analysis (P>0.05). A significant difference (P<0.01) was reported when different operators undertook image analysis, one operator consistently returning larger measurements. Different operators undertaking different stages of an examination can result in significant variability. To reduce confounding during ultrasonographic investigations involving multiple persons, one operator should undertake image analysis, although different operators may undertake image acquisition.

Evolutionary design optimization of traffic signals applied to Quito city.

PubMed

Armas, Rolando; Aguirre, Hernán; Daolio, Fabio; Tanaka, Kiyoshi

2017-01-01

This work applies evolutionary computation and machine learning methods to study the transportation system of Quito from a design optimization perspective. It couples an evolutionary algorithm with a microscopic transport simulator and uses the outcome of the optimization process to deepen our understanding of the problem and gain knowledge about the system. The work focuses on the optimization of a large number of traffic lights deployed on a wide area of the city and studies their impact on travel time, emissions and fuel consumption. An evolutionary algorithm with specialized mutation operators is proposed to search effectively in large decision spaces, evolving small populations for a short number of generations. The effects of the operators combined with a varying mutation schedule are studied, and an analysis of the parameters of the algorithm is also included. In addition, hierarchical clustering is performed on the best solutions found in several runs of the algorithm. An analysis of signal clusters and their geolocation, estimation of fuel consumption, spatial analysis of emissions, and an analysis of signal coordination provide an overall picture of the systemic effects of the optimization process.

Evolutionary design optimization of traffic signals applied to Quito city

PubMed Central

2017-01-01

This work applies evolutionary computation and machine learning methods to study the transportation system of Quito from a design optimization perspective. It couples an evolutionary algorithm with a microscopic transport simulator and uses the outcome of the optimization process to deepen our understanding of the problem and gain knowledge about the system. The work focuses on the optimization of a large number of traffic lights deployed on a wide area of the city and studies their impact on travel time, emissions and fuel consumption. An evolutionary algorithm with specialized mutation operators is proposed to search effectively in large decision spaces, evolving small populations for a short number of generations. The effects of the operators combined with a varying mutation schedule are studied, and an analysis of the parameters of the algorithm is also included. In addition, hierarchical clustering is performed on the best solutions found in several runs of the algorithm. An analysis of signal clusters and their geolocation, estimation of fuel consumption, spatial analysis of emissions, and an analysis of signal coordination provide an overall picture of the systemic effects of the optimization process. PMID:29236733

Preliminary Analysis of Ground-based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Brad

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Preliminary Analysis of Ground-Based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Bradley; Myers, Jessica; Lorah, John; Webster, Cassandra

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations'' scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

The performance of blood pressure-to-height ratio as a screening measure for identifying children and adolescents with hypertension: a meta-analysis.

PubMed

Ma, Chunming; Liu, Yue; Lu, Qiang; Lu, Na; Liu, Xiaoli; Tian, Yiming; Wang, Rui; Yin, Fuzai

2016-02-01

The blood pressure-to-height ratio (BPHR) has been shown to be an accurate index for screening hypertension in children and adolescents. The aim of the present study was to perform a meta-analysis to assess the performance of BPHR for the assessment of hypertension. Electronic and manual searches were performed to identify studies of the BPHR. After methodological quality assessment and data extraction, pooled estimates of the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, area under the receiver operating characteristic curve and summary receiver operating characteristics were assessed systematically. The extent of heterogeneity for it was assessed. Six studies were identified for analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio values of BPHR, for assessment of hypertension, were 96% [95% confidence interval (CI)=0.95-0.97], 90% (95% CI=0.90-0.91), 10.68 (95% CI=8.03-14.21), 0.04 (95% CI=0.03-0.07) and 247.82 (95% CI=114.50-536.34), respectively. The area under the receiver operating characteristic curve was 0.9472. The BPHR had higher diagnostic accuracies for identifying hypertension in children and adolescents.

Nursing home cost and ownership type: evidence of interaction effects.

PubMed

Arling, G; Nordquist, R H; Capitman, J A

1987-06-01

Due to steadily increasing public expenditures for nursing home care, much research has focused on factors that influence nursing home costs, especially for Medicaid patients. Nursing home cost function studies have typically used a number of predictor variables in a multiple regression analysis to determine the effect of these variables on operating cost. Although several authors have suggested that nursing home ownership types have different goal orientations, not necessarily based on economic factors, little attention has been paid to this issue in empirical research. In this study, data from 150 Virginia nursing homes were used in multiple regression analysis to examine factors accounting for nursing home operating costs. The context of the study was the Virginia Medicaid reimbursement system, which has intermediate care and skilled nursing facility (ICF and SNF) facility-specific per diem rates, set according to facility cost histories. The analysis revealed interaction effects between ownership and other predictor variables (e.g., percentage Medicaid residents, case mix, and region), with predictor variables having different effects on cost depending on ownership type. Conclusions are drawn about the goal orientations and behavior of chain-operated, individual for-profit, and public and nonprofit facilities. The implications of these findings for long-term care reimbursement policies are discussed.

Nursing home cost and ownership type: evidence of interaction effects.

PubMed Central

Arling, G; Nordquist, R H; Capitman, J A

1987-01-01

Due to steadily increasing public expenditures for nursing home care, much research has focused on factors that influence nursing home costs, especially for Medicaid patients. Nursing home cost function studies have typically used a number of predictor variables in a multiple regression analysis to determine the effect of these variables on operating cost. Although several authors have suggested that nursing home ownership types have different goal orientations, not necessarily based on economic factors, little attention has been paid to this issue in empirical research. In this study, data from 150 Virginia nursing homes were used in multiple regression analysis to examine factors accounting for nursing home operating costs. The context of the study was the Virginia Medicaid reimbursement system, which has intermediate care and skilled nursing facility (ICF and SNF) facility-specific per diem rates, set according to facility cost histories. The analysis revealed interaction effects between ownership and other predictor variables (e.g., percentage Medicaid residents, case mix, and region), with predictor variables having different effects on cost depending on ownership type. Conclusions are drawn about the goal orientations and behavior of chain-operated, individual for-profit, and public and nonprofit facilities. The implications of these findings for long-term care reimbursement policies are discussed. PMID:3301746

Using task analysis to understand the Data System Operations Team

NASA Technical Reports Server (NTRS)

Holder, Barbara E.

1994-01-01

The Data Systems Operations Team (DSOT) currently monitors the Multimission Ground Data System (MGDS) at JPL. The MGDS currently supports five spacecraft and within the next five years, it will support ten spacecraft simultaneously. The ground processing element of the MGDS consists of a distributed UNIX-based system of over 40 nodes and 100 processes. The MGDS system provides operators with little or no information about the system's end-to-end processing status or end-to-end configuration. The lack of system visibility has become a critical issue in the daily operation of the MGDS. A task analysis was conducted to determine what kinds of tools were needed to provide DSOT with useful status information and to prioritize the tool development. The analysis provided the formality and structure needed to get the right information exchange between development and operations. How even a small task analysis can improve developer-operator communications is described, and the challenges associated with conducting a task analysis in a real-time mission operations environment are examined.

Trends in hospital efficiency among metropolitan markets.

PubMed

Wang, B B; Ozcan, Y A; Wan, T T; Harrison, J

1999-04-01

This study evaluates trends in efficiency among American hospital markets. A total of 6010 hospitals were identified for use in the analysis from the American Hospital Association's Annual Surveys for 1989 and 1993. Using data envelopment analysis (DEA), a longitudinal study of hospital efficiency was conducted on all 314 metropolitan markets in the United States. Results suggest that large hospital markets generally demonstrated higher inefficiency. The major inefficiencies exist in the availability of hospital services, the number of operating beds, the utilization of hospital staffing and operating expenses. Consequently, the large hospital market had a significant excess of health manpower that resulted in inefficiency that amounted to approximately $23 billion. From a policy perspective, this study has shed some light on the need to establish more specific policies to address inefficiency in the health care industry.

Follow-On Technology Requirement Study for Advanced Subsonic Transport

NASA Technical Reports Server (NTRS)

Wendus, Bruce E.; Stark, Donald F.; Holler, Richard P.; Funkhouser, Merle E.

2003-01-01

A study was conducted to define and assess the critical or enabling technologies required for a year 2005 entry into service (EIS) engine for subsonic commercial aircraft, with NASA Advanced Subsonic Transport goals used as benchmarks. The year 2005 EIS advanced technology engine is an Advanced Ducted Propulsor (ADP) engine. Performance analysis showed that the ADP design offered many advantages compared to a baseline turbofan engine. An airplane/ engine simulation study using a long range quad aircraft quantified the effects of the ADP engine on the economics of typical airline operation. Results of the economic analysis show the ADP propulsion system provides a 6% reduction in direct operating cost plus interest, with half the reduction resulting from reduced fuel consumption. Critical and enabling technologies for the year 2005 EIS ADP were identified and prioritized.

Benefit Opportunities for Integrated Surface and Airspace Departure Scheduling: A Study of Operations at Charlotte-Douglas International Airport

NASA Technical Reports Server (NTRS)

Coppenbarger, Rich; Jung, Yoon; Kozon, Tom; Farrahi, Amir; Malik, Wakar; Lee, Hanbong; Chevalley, Eric; Kistler, Matt

2016-01-01

NASA is collaborating with the FAA and aviation industry to develop and demonstrate new capabilities that integrate arrival, departure, and surface air-traffic operations. The concept relies on trajectory-based departure scheduling and collaborative decision making to reduce delays and uncertainties in taxi and climb operations. The paper describes the concept and benefit mechanisms aimed at improving flight efficiency and predictability while maintaining or improving operational throughput. The potential impact of the technology is studied and discussed through a quantitative analysis of relevant shortfalls at the site identified for initial deployment and demonstration in 2017: Charlotte-Douglas International Airport. Results from trajectory analysis indicate substantial opportunity to reduce taxi delays for both departures and arrivals by metering departures at the gate in a manner that maximizes throughput while adhering to takeoff restrictions due mostly to airspace constraints. Substantial taxi-out delay reduction is shown for flights subject to departure restrictions stemming from traffic flow management initiatives. Opportunities to improve the predictability of taxi, takeoff, and climb operations are examined and their potential impact on airline scheduling decisions and air-traffic forecasting is discussed. In addition, the potential to improve throughput with departure scheduling that maximizes use of available runway and airspace capacity is analyzed.

Land suitability for establishing rainwater harvesting systems for fighting wildfires

Treesearch

José María León Villalobos; Manuel Anaya Garduño; Enrique Ojeda Trejo; Dante Arturo Rodríguez Trejo; José Luis Oropeza Mota; Jorge Luis García Rodríguez

2013-01-01

Rainwater harvesting systems (RHSs) can be used to improve the efficiency of helicopter firefighting operations. To this end, RHSs need to be strategically located in areas with high wildfire occurrence to maximize their usefulness. In this study, spatial analysis was carried out to determine suitable sites for establishing RHSs intended for air attack operations in...

Selected Research Abstracts of Published and Unpublished Reports Pertaining to the Food Service Industry, Including Recommendations for Research Needs.

ERIC Educational Resources Information Center

Nejelski, Leo

The 251 research abstracts, dated 1956-1968, are arranged under these areas: (1) Industry Statistics and Feasbility Studies, (2) Merchandising, (3) Purchasing, (4) Facilities Design and Operations Analysis, (5) Commissary Operations, (6) Finance and Cost Control, and (7) Personnel Management. Research gaps, determined through interviews with…

Self-Injurious Behavior in Rett Syndrome: Interactions between Features of Rett Syndrome and Operant Conditioning.

ERIC Educational Resources Information Center

Oliver, Chris; And Others

1993-01-01

In this case study, interactions were examined between features of Rett syndrome and operant conditioning as determinants of self-injurious behavior (SIB). Analysis suggested different functions for two forms of SIB: automatic reinforcement by sensory stimulation and escape from social interactions. Features of Rett syndrome tended to maximize the…

Effects of Reinforcement Schedule on Facilitation of Operant Extinction by Chlordiazepoxide

ERIC Educational Resources Information Center

Leslie, Julian C.; Shaw, David; Gregg, Gillian; McCormick, Nichola; Reynolds, David S.; Dawson, Gerard R.

2005-01-01

Learning and memory are central topics in behavioral neuroscience, and inbred mice strains are widely investigated. However, operant conditioning techniques are not as extensively used in this field as they should be, given the effectiveness of the methodology of the experimental analysis of behavior. In the present study, male C57Bl/6 mice,…

Transferring Control of the Mand to the Motivating Operation in Children with Autism

ERIC Educational Resources Information Center

Sweeney-Kerwin, Emily J.; Carbone, Vincent J.; O'Brien, Leigh; Zecchin, Gina; Janecky, Marietta N.

2007-01-01

Few studies have made use of B. F. Skinner's (1957) behavioral analysis of language and precise taxonomy of verbal behavior when describing the controlling variables for the mand relation. Consequently, the motivating operation (MO) has not typically been identified as an independent variable and the nature of a spontaneous mand has been…

Community College Finance: A Cost Analysis of Community College Expenditures Related to Maintenance and Operations

ERIC Educational Resources Information Center

Collins, Michael T.

2011-01-01

The purpose of this study is to develop a costing model for maintenance and operations expenditures among 16 single-campus California community college districts and assess the impact of a variety of variables including size of student enrollment, physical plant age, acreage, gross square footage, and general obligation facility bonds on district…

American Association of University Women: Branch Operations Data Modeling Case

ERIC Educational Resources Information Center

Harris, Ranida B.; Wedel, Thomas L.

2015-01-01

A nationally prominent woman's advocacy organization is featured in this case study. The scenario may be used as a teaching case, an assignment, or a project in systems analysis and design as well as database design classes. Students are required to document the system operations and requirements, apply logical data modeling concepts, and design…

Space tug economic analysis study. Volume 2: Tug concepts analysis. Part 1: Overall approach and data generation

NASA Technical Reports Server (NTRS)

1972-01-01

An economic analysis of space tug operations is presented. The subjects discussed are: (1) data base for orbit injection stages, (2) data base for reusable space tug, (3) performance equations, (4) data integration and interpretation, (5) tug performance and mission model accomodation, (6) total program cost, (7) payload analysis, (8) computer software, and (9) comparison of tug concepts.

Iraqi Population Displacement Analysis

DTIC Science & Technology

2016-11-01

CENTER FOR ARMY ANALYSIS 6001 GOETHALS ROAD FORT BELVOIR, VA 22060-5230 CAA-2015098 IRAQI POPULATION DISPLACEMENT ANALYSIS NOVEMBER 2016...CONTRACT NUMBER Iraqi Population Displacement Analysis PDMC 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Ms...NOTES 14. ABSTRACT The purpose of this study was to inform CJ34 Civil Military Operations decisions on placement of internally displaced person (IDP

Surgery in adrenocortical carcinoma: Importance of national cooperation and centralized surgery.

PubMed

Hermsen, Ilse G C; Kerkhofs, Thomas M A; den Butter, Gijsbert; Kievit, Job; van Eijck, Casper H J; Nieveen van Dijkum, Els J M; Haak, Harm R

2012-07-01

The low incidence rate of adrenocortical carcinoma (ACC) requires a multidisciplinary approach in which surgery plays an essential role because complete resection of the primary tumor is the only chance of cure. To improve patient care, insight into operative results within the ACC population is essential. In 2007, a Dutch Adrenal Network Registry was created covering care and outcome of patients treated for ACC in the Netherlands since 1965. Using this database, we performed a study (1) to gain insight into surgical performance in the Netherlands and (2) to compare operative data with international literature. Data on patients treated from 1965 until January 2008 were studied. The following data were collected: age, gender, functionality of the tumor, stage at diagnosis, operative procedure, completeness of surgery, disease recurrence, adjuvant mitotane therapy, and recurrence-free and overall survival (OS). A total of 175 patients were studied, of whom 149 underwent surgery. Patients with complete resection had significantly longer OS times than patients with incomplete resection (P = .010). Patients operated on in a Dutch Adrenal Network center had significantly longer duration of OS in both univariate (P = .011) and multivariate analysis (P = .014). A significantly greater OS was observed for operated stage IV patients compared with nonoperated patients (P = .002). Our data suggest the relevance of national cooperation and centralized surgery in ACC. For selected patients with stage IV disease, surgery can be beneficial in extending survival. On the basis of the retrospective analysis, operative ACC in the Netherlands can and will be improved. Copyright © 2012. Published by Mosby, Inc.

The operational context of care sport connectors in the Netherlands.

PubMed

Leenaars, K E F; van der Velden-Bollemaat, E C; Smit, E; Wagemakers, A; Molleman, G R M; Koelen, M A

2017-02-22

To stimulate physical activity (PA) and guide primary care patients towards local sport facilities, Care Sport Connectors (CSCs), to whom a broker role has been ascribed, were introduced in 2012 in the Netherlands. The aim of this study is to describe CSCs' operational context. A theoretical framework was developed and used as the starting point for this study. Group interviews were held with policymakers in nine participating municipalities, and, when applicable, the CSC's manager was also present. Prior to the interviews, a first outline of the operational context was mapped, based on the analysis of policy documents and a questionnaire completed by the policymakers. A deductive content analysis, based on the theoretical framework, was used to analyse the interviews. Differences were found in CSCs' operational context in the different municipalities, especially the extent to which municipalities adopted an integral approach. An integral approach consists of an integral policy in combination with an imbedding of this policy in partnerships at management level. This integral approach is reflected in the activities of other municipal operations, for example the implementation of health and PA programs by different organisations. Given the CSC mandate, we think that this integral approach may be supportive of the CSCs' work, because it is reflected in other operations of the municipalities and thus creates conditions for the CSCs' work. Further study is required to ascertain whether this integral approach is actually supporting CSCs in their work to connect the primary care and the PA sector. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[A field study on the work load and muscle fatigue at neck-shoulder in female sewing machine operators by using surface electromyography].

PubMed

Zhang, Fei-ruo; Wang, Sheng; He, Li-hua; Zhang, Ying; Wu, Shan-shan; Li, Jing-yun; Hu, Guang-yi; Ye, Kang-ping

2011-03-01

To study neck and shoulder work-related muscle fatigue of female sewing machine operators. 18 health female sewing machine operators without musculoskeletal disorders work in Beijing garment industry factory as volunteers in participate of this study. The maximal voluntary contraction (MVC) and 20% MVC of bilateral upper trapezium and cervical erectors spinae was tested before sewing operations, then the whole 20 time windows (1 time window = 10 min) sewing machine operations was monitored and the surface electromyography (sEMG) signals simultaneously was recorded after monitoring the 20%MVC was tested. Use amplitude analysis method to reduction recorded EMG signals. During work, the median load for the left cervical erector spinae (LCES), right cervical erector spinae (RCES), left upper trapezium (LUT) and right upper trapezium (RUT) respectively was 6.78 ± 1.05, 6.94 ± 1.12, 5.68 ± 2.56 and 6.47 ± 3.22, work load of right is higher than the left; static load analysis indicated the value of RMS(20%MVC) before work was higher than that value after work, the increase of right CES and UT RMS(20%MVC) was more; the largest 20%MVE of bilateral CES occurred at 20th time window, and that of bilateral UT happened at 16th. The work load of female sewing machine operators is sustained "static" load, and work load of right neck-shoulder is higher than left, right neck-shoulder muscle is more fatigable and much serious once fatigued.

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR LABORATORY ANALYSIS OF HAIR SAMPLES FOR MERCURY (RTI-L-1.0)

EPA Science Inventory

The purpose of this protocol is to provide guidelines for the analysis of hair samples for total mercury by cold vapor atomic fluorescence (CVAFS) spectrometry. This protocol describes the methodology and all other analytical aspects involved in the analysis. Keywords: hair; s...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR ANALYSIS OF VOLATILE ORGANIC COMPOUNDS COLLECTED WITH A PASSIVE SAMPLER (BCO-L-17.1)

EPA Science Inventory

The purpose of this SOP is to describe the methodology used for the analysis of the 3M OVM 3500 Organic Vapor Monitors for volatile organic compounds (VOCs), using solvent extraction and standard gas chromatography/mass spectrometry (GC/MS) analysis procedures. This procedure was...

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR ANALYSIS OF PESTICIDE SAMPLES BY GC/MS (BCO-L-15.1)

EPA Science Inventory

The purpose of this SOP is to describe the methods used for detection and quantification by gas chromatography/mass spectrometry (GC/MS) of pesticides in a variety of matrices, including air, house dust, soil, and handwipes. This analysis involves automated gas GC/MS analysis us...

Solar power satellite system definition study, volume 5. Phase 2: Final briefing

NASA Technical Reports Server (NTRS)

1979-01-01

A briefing outline of the definition study is presented. Topics discussed include: Solar Power Satellite (SPS) research and development, definition study, operations control, transportation, solid state SPS, pilot link analysis, and offshore space center.

Tumour heterogeneity in glioblastoma assessed by MRI texture analysis: a potential marker of survival

PubMed Central

Pérez-Beteta, Julián; Luque, Belén; Arregui, Elena; Calvo, Manuel; Borrás, José M; López, Carlos; Martino, Juan; Velasquez, Carlos; Asenjo, Beatriz; Benavides, Manuel; Herruzo, Ismael; Martínez-González, Alicia; Pérez-Romasanta, Luis; Arana, Estanislao; Pérez-García, Víctor M

2016-01-01

Objective: The main objective of this retrospective work was the study of three-dimensional (3D) heterogeneity measures of post-contrast pre-operative MR images acquired with T1 weighted sequences of patients with glioblastoma (GBM) as predictors of clinical outcome. Methods: 79 patients from 3 hospitals were included in the study. 16 3D textural heterogeneity measures were computed including run-length matrix (RLM) features (regional heterogeneity) and co-occurrence matrix (CM) features (local heterogeneity). The significance of the results was studied using Kaplan–Meier curves and Cox proportional hazards analysis. Correlation between the variables of the study was assessed using the Spearman's correlation coefficient. Results: Kaplan–Meyer survival analysis showed that 4 of the 11 RLM features and 4 of the 5 CM features considered were robust predictors of survival. The median survival differences in the most significant cases were of over 6 months. Conclusion: Heterogeneity measures computed on the post-contrast pre-operative T1 weighted MR images of patients with GBM are predictors of survival. Advances in knowledge: Texture analysis to assess tumour heterogeneity has been widely studied. However, most works develop a two-dimensional analysis, focusing only on one MRI slice to state tumour heterogeneity. The study of fully 3D heterogeneity textural features as predictors of clinical outcome is more robust and is not dependent on the selected slice of the tumour. PMID:27319577

Tumour heterogeneity in glioblastoma assessed by MRI texture analysis: a potential marker of survival.

PubMed

Molina, David; Pérez-Beteta, Julián; Luque, Belén; Arregui, Elena; Calvo, Manuel; Borrás, José M; López, Carlos; Martino, Juan; Velasquez, Carlos; Asenjo, Beatriz; Benavides, Manuel; Herruzo, Ismael; Martínez-González, Alicia; Pérez-Romasanta, Luis; Arana, Estanislao; Pérez-García, Víctor M

2016-07-04

The main objective of this retrospective work was the study of three-dimensional (3D) heterogeneity measures of post-contrast pre-operative MR images acquired with T 1 weighted sequences of patients with glioblastoma (GBM) as predictors of clinical outcome. 79 patients from 3 hospitals were included in the study. 16 3D textural heterogeneity measures were computed including run-length matrix (RLM) features (regional heterogeneity) and co-occurrence matrix (CM) features (local heterogeneity). The significance of the results was studied using Kaplan-Meier curves and Cox proportional hazards analysis. Correlation between the variables of the study was assessed using the Spearman's correlation coefficient. Kaplan-Meyer survival analysis showed that 4 of the 11 RLM features and 4 of the 5 CM features considered were robust predictors of survival. The median survival differences in the most significant cases were of over 6 months. Heterogeneity measures computed on the post-contrast pre-operative T 1 weighted MR images of patients with GBM are predictors of survival. Texture analysis to assess tumour heterogeneity has been widely studied. However, most works develop a two-dimensional analysis, focusing only on one MRI slice to state tumour heterogeneity. The study of fully 3D heterogeneity textural features as predictors of clinical outcome is more robust and is not dependent on the selected slice of the tumour.

Thermal Analysis Study of Antihypertensive Drugs Telmisartan and Cilazapril

PubMed Central

Saber, Refaat Ahmed; Attia, Ali Kamal; Salem, Waheed Mohamed

2014-01-01

Purpose: The aim of the present work is to study the thermal analysis of telmisartan and cilazapril. Methods: Thermogravimetry (TGA), derivative thermogravimetry (DTG) and differential thermal analysis (DTA) were used through the work to achieve the thermal analysis study of some antihypertensive drugs, telmisartan and cilazapril. Results: The results led to thermal stability data and also to the interpretation concerning the thermal decomposition. Thermogravimetry data allowed determination of the kinetic parameters such as, activation energy and frequency factor. Conclusion: The simplicity, speed and low operational costs of thermal analysis justify its application in the quality control of pharmaceutical compounds for medications. PMID:24754013

A preliminary benefit-cost study of a Sandia wind farm.

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

Ehlen, Mark Andrew; Griffin, Taylor; Loose, Verne W.

In response to federal mandates and incentives for renewable energy, Sandia National Laboratories conducted a feasibility study of installing an on-site wind farm on Sandia National Laboratories and Kirtland Air Force Base property. This report describes this preliminary analysis of the costs and benefits of installing and operating a 15-turbine, 30-MW-capacity wind farm that delivers an estimated 16 percent of 2010 onsite demand. The report first describes market and non-market economic costs and benefits associated with operating a wind farm, and then uses a standard life-cycle costing and benefit-cost framework to estimate the costs and benefits of a wind farm.more » Based on these 'best-estimates' of costs and benefits and on factor, uncertainty and sensitivity analysis, the analysis results suggest that the benefits of a Sandia wind farm are greater than its costs. The analysis techniques used herein are applicable to the economic assessment of most if not all forms of renewable energy.« less

Whole-Lesion Histogram Analysis of Apparent Diffusion Coefficient for the Assessment of Cervical Cancer.

PubMed

Guan, Yue; Shi, Hua; Chen, Ying; Liu, Song; Li, Weifeng; Jiang, Zhuoran; Wang, Huanhuan; He, Jian; Zhou, Zhengyang; Ge, Yun

2016-01-01

The aim of this study was to explore the application of whole-lesion histogram analysis of apparent diffusion coefficient (ADC) values of cervical cancer. A total of 54 women (mean age, 53 years) with cervical cancers underwent 3-T diffusion-weighted imaging with b values of 0 and 800 s/mm prospectively. Whole-lesion histogram analysis of ADC values was performed. Paired sample t test was used to compare differences in ADC histogram parameters between cervical cancers and normal cervical tissues. Receiver operating characteristic curves were constructed to identify the optimal threshold of each parameter. All histogram parameters in this study including ADCmean, ADCmin, ADC10%-ADC90%, mode, skewness, and kurtosis of cervical cancers were significantly lower than those of normal cervical tissues (all P < 0.0001). ADC90% had the largest area under receiver operating characteristic curve of 0.996. Whole-lesion histogram analysis of ADC maps is useful in the assessment of cervical cancer.

Design study for a high reliability five-year spacecraft tape transport

NASA Technical Reports Server (NTRS)

Benn, G. S. L.; Eshleman, R. L.

1971-01-01

Following the establishment of the overall transport concept, a study of all of the life limiting constraints associated with the transport were analyzed using modeling techniques. These design techniques included: (1) a response analysis from which the performance of the transport could be determined under operating conditions for a variety of conceptual variations both in a new and aged condition; (2) an analysis of a double cone guidance technique which yielded an optimum design for maximum guidance with minimum tape degradation; (3) an analysis of the tape pack design to eliminate spoking caused by negative tangential stress within the pack; (4) an evaluation of the stress levels experienced by the magnetic tape throughout the system; (5) a general review of the bearing and lubrication technology as applied to satellite recorders and hence the recommendation for using standard load carrying antifriction ball bearings; and (6) a kinetic analysis to determine the change in kinetic properties of the transport during operation.

Error analysis of mathematical problems on TIMSS: A case of Indonesian secondary students

NASA Astrophysics Data System (ADS)

Priyani, H. A.; Ekawati, R.

2018-01-01

Indonesian students’ competence in solving mathematical problems is still considered as weak. It was pointed out by the results of international assessment such as TIMSS. This might be caused by various types of errors made. Hence, this study aimed at identifying students’ errors in solving mathematical problems in TIMSS in the topic of numbers that considered as the fundamental concept in Mathematics. This study applied descriptive qualitative analysis. The subject was three students with most errors in the test indicators who were taken from 34 students of 8th graders. Data was obtained through paper and pencil test and student’s’ interview. The error analysis indicated that in solving Applying level problem, the type of error that students made was operational errors. In addition, for reasoning level problem, there are three types of errors made such as conceptual errors, operational errors and principal errors. Meanwhile, analysis of the causes of students’ errors showed that students did not comprehend the mathematical problems given.

Using motion capture technology to measure the effects of magnification loupes on dental operator posture: A pilot study.

PubMed

Branson, B G; Abnos, R M; Simmer-Beck, M L; King, G W; Siddicky, S F

2018-01-01

Motion analysis has great potential for quantitatively evaluating dental operator posture and the impact of interventions such as magnification loupes on posture and subsequent development of musculoskeletal disorders. This study sought to determine the feasibility of motion capture technology for measurement of dental operator posture and examine the impact that different styles of magnification loupes had on dental operator posture. Forward and lateral head flexion were measured for two different operators while completing a periodontal probing procedure. Each was measured while wearing magnification loupes (flip up-FL and through the lens-TTL) and basic safety lenses. Operators both exhibited reduced forward flexion range of motion (ROM) when using loupes (TTL or FL) compared to a baseline lens (BL). In contrast to forward flexion, no consistent trends were observed for lateral flexion between subjects. The researchers can report that it is possible to measure dental operator posture using motion capture technology. More study is needed to determine which type of magnification loupes (FL or TTL) are superior in improving dental operator posture. Some evidence was found supporting that the quality of operator posture may more likely be related to the use of magnification loupes, rather than the specific type of lenses worn.

On the effective operators for Dark Matter annihilations

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

Simone, Andrea De; Thamm, Andrea; Monin, Alexander

2013-02-01

We consider effective operators describing Dark Matter (DM) interactions with Standard Model fermions. In the non-relativistic limit of the DM field, the operators can be organized according to their mass dimension and their velocity behaviour, i.e. whether they describe s- or p-wave annihilations. The analysis is carried out for self-conjugate DM (real scalar or Majorana fermion). In this case, the helicity suppression at work in the annihilation into fermions is lifted by electroweak bremsstrahlung. We construct and study all dimension-8 operators encoding such an effect. These results are of interest in indirect DM searches.

Analysis of remote operating systems for space-based servicing operations, volume 1

NASA Technical Reports Server (NTRS)

1985-01-01

A two phase study was conducted to analyze and develop the requirements for remote operating systems as applied to space based operations for the servicing, maintenance, and repair of satellites. Phase one consisted of the development of servicing requirements to establish design criteria for remote operating systems. Phase two defined preferred system concepts and development plans which met the requirements established in phase one. The specific tasks in phase two were to: (1) identify desirable operational and conceptual approaches for selected mission scenarios; (2) examine the potential impact of remote operating systems incorporated into the design of the space station; (3) address remote operating systems design issues, such as mobility, which are effected by the space station configuration; and (4) define the programmatic approaches for technology development, testing, simulation, and flight demonstration.

A Multi-Methods Approach to HRA and Human Performance Modeling: A Field Assessment

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

Jacques Hugo; David I Gertman

2012-06-01

The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory is primarily designed and used to test materials to be used in other, larger-scale and prototype reactors. The reactor offers various specialized systems and allows certain experiments to be run at their own temperature and pressure. The ATR Canal temporarily stores completed experiments and used fuel. It also has facilities to conduct underwater operations such as experiment examination or removal. In reviewing the ATR safety basis, a number of concerns were identified involving the ATR canal. A brief study identified ergonomic issues involving the manual handlingmore » of fuel elements in the canal that may increase the probability of human error and possible unwanted acute physical outcomes to the operator. In response to this concern, that refined the previous HRA scoping analysis by determining the probability of the inadvertent exposure of a fuel element to the air during fuel movement and inspection was conducted. The HRA analysis employed the SPAR-H method and was supplemented by information gained from a detailed analysis of the fuel inspection and transfer tasks. This latter analysis included ergonomics, work cycles, task duration, and workload imposed by tool and workplace characteristics, personal protective clothing, and operational practices that have the potential to increase physical and mental workload. Part of this analysis consisted of NASA-TLX analyses, combined with operational sequence analysis, computational human performance analysis (CHPA), and 3D graphical modeling to determine task failures and precursors to such failures that have safety implications. Experience in applying multiple analysis techniques in support of HRA methods is discussed.« less

Induced simplified neutrosophic correlated aggregation operators for multi-criteria group decision-making

NASA Astrophysics Data System (ADS)

Şahin, Rıdvan; Zhang, Hong-yu

2018-03-01

Induced Choquet integral is a powerful tool to deal with imprecise or uncertain nature. This study proposes a combination process of the induced Choquet integral and neutrosophic information. We first give the operational properties of simplified neutrosophic numbers (SNNs). Then, we develop some new information aggregation operators, including an induced simplified neutrosophic correlated averaging (I-SNCA) operator and an induced simplified neutrosophic correlated geometric (I-SNCG) operator. These operators not only consider the importance of elements or their ordered positions, but also take into account the interactions phenomena among decision criteria or their ordered positions under multiple decision-makers. Moreover, we present a detailed analysis of I-SNCA and I-SNCG operators, including the properties of idempotency, commutativity and monotonicity, and study the relationships among the proposed operators and existing simplified neutrosophic aggregation operators. In order to handle the multi-criteria group decision-making (MCGDM) situations where the weights of criteria and decision-makers usually correlative and the criterion values are considered as SNNs, an approach is established based on I-SNCA operator. Finally, a numerical example is presented to demonstrate the proposed approach and to verify its effectiveness and practicality.

Analysis Of The Effects Of Marine Corps M1A1 Abram’s Tank Age On Operational Availability

DTIC Science & Technology

2014-06-01

effects of age, as measured by the time since the last depot- level rebuild, on equipment operational availability for the M1A1 MBT in the Marine Corps...prior M1A1 reliability studies. We reviewed depot- and unit- level maintenance records within the USMC’s System Operational Effectiveness database to... Level Maintenance 15. NUMBER OF PAGES 67 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF

Evidence-based value of subcutaneous surgical wound drainage: the largest systematic review and meta-analysis.

PubMed

Kosins, Aaron M; Scholz, Thomas; Cetinkaya, Mine; Evans, Gregory R D

2013-08-01

The purpose of this study was to determine the evidenced-based value of prophylactic drainage of subcutaneous wounds in surgery. An electronic search was performed. Articles comparing subcutaneous prophylactic drainage with no drainage were identified and classified by level of evidence. If sufficient randomized controlled trials were included, a meta-analysis was performed using the random-effects model. Fifty-two randomized controlled trials were included in the meta-analysis, and subgroups were determined by specific surgical procedures or characteristics (cesarean delivery, abdominal wound, breast reduction, breast biopsy, femoral wound, axillary lymph node dissection, hip and knee arthroplasty, obesity, and clean-contaminated wound). Studies were compared for the following endpoints: hematoma, wound healing issues, seroma, abscess, and infection. Fifty-two studies with a total of 6930 operations were identified as suitable for this analysis. There were 3495 operations in the drain group and 3435 in the no-drain group. Prophylactic subcutaneous drainage offered a statistically significant advantage only for (1) prevention of hematomas in breast biopsy procedures and (2) prevention of seromas in axillary node dissections. In all other procedures studied, drainage did not offer an advantage. Many surgical operations can be performed safely without prophylactic drainage. Surgeons can consider omitting drains after cesarean section, breast reduction, abdominal wounds, femoral wounds, and hip and knee joint replacement. Furthermore, surgeons should consider not placing drains prophylactically in obese patients. However, drain placement following a surgical procedure is the surgeon's choice and can be based on multiple factors beyond the type of procedure being performed or the patient's body habitus. Therapeutic, II.

Advanced Transportation System Studies Technical Area 2 (TA-2) Heavy Lift Launch Vehicle Development Contract. Volume 2; Technical Results

NASA Technical Reports Server (NTRS)

1995-01-01

The purpose of the Advanced Transportation System Studies (ATSS) Technical Area 2 (TA-2) Heavy Lift Launch Vehicle Development contract was to provide advanced launch vehicle concept definition and analysis to assist NASA in the identification of future launch vehicle requirements. Contracted analysis activities included vehicle sizing and performance analysis, subsystem concept definition, propulsion subsystem definition (foreign and domestic), ground operations and facilities analysis, and life cycle cost estimation. This document is Volume 2 of the final report for the contract. It provides documentation of selected technical results from various TA-2 analysis activities, including a detailed narrative description of the SSTO concept assessment results, a user's guide for the associated SSTO sizing tools, an SSTO turnaround assessment report, an executive summary of the ground operations assessments performed during the first year of the contract, a configuration-independent vehicle health management system requirements report, a copy of all major TA-2 contract presentations, a copy of the FLO launch vehicle final report, and references to Pratt & Whitney's TA-2 sponsored final reports regarding the identification of Russian main propulsion technologies.

Space transfer vehicle concepts and requirements study. Volume 2, book 1: STV concept definition and evaluation

NASA Technical Reports Server (NTRS)

Weber, Gary A.

1991-01-01

The topics covered include the following: mission analysis; initial and evolutionary space transfer vehicle (STV) concept definition; configuration and subsystem trade studies; and operations and logistics.

A profile of fatal accidents involving alcohol

DOT National Transportation Integrated Search

1977-09-01

Author's abstract: Accident investigation studies were conducted during 1971-75 in the cities of Boston, Baltimore, Oklahoma City and Albuquerque where Alcohol Safety Action Programs (ASAPs) were operating. Analysis of the four studies, plus newly av...

Accuracy and usefulness of the AVOXimeter 4000 as routine analysis of carboxyhemoglobin.

PubMed

Fujihara, Junko; Kinoshita, Hiroshi; Tanaka, Naoko; Yasuda, Toshihiro; Takeshita, Haruo

2013-07-01

The measurement of blood carboxyhemoglobin (CO-Hb) is important to determine the cause of death. The AVOXimeter 4000 (AVOX), a portable CO-oximeter, has the advantages of a low purchase price and operating cost, ease of operation, and rapid results. Little information is available on the usefulness of AVOX in the forensic sample, and the previous study investigated only six samples. Therefore, in this study, we confirmed the usefulness of the AVOX through a comparison of its results with data previously obtained using the double wavelength spectrophotometric method in autopsies. Regression analysis was performed between CO-Hb levels measured by the AVOX and those measured by the conventional double wavelength spectrophotometric method in postmortem blood samples: a significant correlation was observed. This study suggests the usefulness of the AVOX to analyze postmortem blood, and the AVOX is suitable for routine forensic analysis and can be applied at the crime scene. © 2013 American Academy of Forensic Sciences.

Conjoint Analysis for New Service Development on Electricity Distribution in Indonesia

NASA Astrophysics Data System (ADS)

Widaningrum, D. L.; Chynthia; Astuti, L. D.; Seran, M. A. B.

2017-07-01

Many cases of illegal use of electricity in Indonesia is still rampant, especially for activities where the power source is not available, such as in the location of street vendors. It is not only detrimental to the state, but also harm the perpetrators of theft of electricity and the surrounding communities. The purpose of this study is to create New Service Development (NSD) to provide a new electricity source for street vendors' activity based on their preferences. The methods applied in NSD is Conjoint Analysis, Cluster Analysis, Quality Function Deployment (QFD), Service Blueprint, Process Flow Diagrams and Quality Control Plan. The results of this study are the attributes and their importance in the new electricity’s service based on street vendors’ preferences as customers, customer segmentation, service design for new service, designing technical response, designing operational procedures, the quality control plan of any existing operational procedures.

Turing pattern dynamics and adaptive discretization for a super-diffusive Lotka-Volterra model.

PubMed

Bendahmane, Mostafa; Ruiz-Baier, Ricardo; Tian, Canrong

2016-05-01

In this paper we analyze the effects of introducing the fractional-in-space operator into a Lotka-Volterra competitive model describing population super-diffusion. First, we study how cross super-diffusion influences the formation of spatial patterns: a linear stability analysis is carried out, showing that cross super-diffusion triggers Turing instabilities, whereas classical (self) super-diffusion does not. In addition we perform a weakly nonlinear analysis yielding a system of amplitude equations, whose study shows the stability of Turing steady states. A second goal of this contribution is to propose a fully adaptive multiresolution finite volume method that employs shifted Grünwald gradient approximations, and which is tailored for a larger class of systems involving fractional diffusion operators. The scheme is aimed at efficient dynamic mesh adaptation and substantial savings in computational burden. A numerical simulation of the model was performed near the instability boundaries, confirming the behavior predicted by our analysis.

Cost Savings and Patient Experiences of a Clinic-Based, Wide-Awake Hand Surgery Program at a Military Medical Center: A Critical Analysis of the First 100 Procedures.

PubMed

Rhee, Peter C; Fischer, Michelle M; Rhee, Laura S; McMillan, Ha; Johnson, Anthony E

2017-03-01

Wide-awake, local anesthesia, no tourniquet (WALANT) hand surgery was developed to improve access to hand surgery care while optimizing medical resources. Hand surgery in the clinic setting may result in substantial cost savings for the United States Military Health Care System (MHS) and provide a safe alternative to performing similar procedures in the operating room. A prospective cohort study was performed on the first 100 consecutive clinic-based WALANT hand surgery procedures performed at a military medical center from January 2014 to September 2015 by a single hand surgeon. Cost savings analysis was performed by using the Medical Expense and Performance Reporting System, the standard cost accounting system for the MHS, to compare procedures performed in the clinic versus the operating room during the study period. A study specific questionnaire was obtained for 66 procedures to evaluate the patient's experience. For carpal tunnel release (n = 34) and A1 pulley release (n = 33), there were 85% and 70% cost savings by having the procedures performed in clinic under WALANT compared with the main operating room, respectively. During the study period, carpal tunnel release, A1 pulley release, and de Quervain release performed in the clinic instead of the operating room amounted to $393,100 in cost savings for the MHS. There were no adverse events during the WALANT procedure. A clinic-based WALANT hand surgery program at a military medical center results in considerable cost savings for the MHS. Economic/Decision Analysis IV. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

A Systematic Review and Meta-Analysis of Baseline Ohip-Edent Scores.

PubMed

Duale, J M J; Patel, Y A; Wu, J; Hyde, T P

2018-03-01

OHIP-EDENT is widely used in the literature to assess Oral-Health-Related-Quality-of-Life (OHRQoL) for edentulous patients. However the normal variance and mean of the baseline OHIP scores has not been reported. It would facilitate critical appraisal of studies if we had knowledge of the normal variation and mean of baseline OHIP-EDENT scores. An established figure for baseline OHIP-EDENT, obtained from a meta-analysis, would simplify comparisons of studies and quantify variations in initial OHRQoL of the trial participants. The aim of this study is to quantify a normal baseline value for pre-operative OHIP-EDENT scores by a systematic review and meta-analysis of the available literature. A systematic literature review was carried. 83 papers were identified that included OHIP-EDENT values. After screening and eligibility assessment, 7 papers were selected and included in the meta-analysis. A meta-analysis for the 7 papers by a random-effect model yielded a mean baseline OHIP-EDENT score of 28.63 with a 95% Confidence intervals from 21.93 to 35.34. A pre-operative baseline OHIP-EDENT has been established by meta-analysis of published papers. This will facilitate the comparison of the initial OHRQoL of one study population to that found elsewhere in the published literature. Copyright© 2018 Dennis Barber Ltd.

Sinus tarsi approach (STA) versus extensile lateral approach (ELA) for treatment of closed displaced intra-articular calcaneal fractures (DIACF): A meta-analysis.

PubMed

Bai, L; Hou, Y-L; Lin, G-H; Zhang, X; Liu, G-Q; Yu, B

2018-04-01

Our aim was to compare the effect of sinus tarsi approach (STA) vs extensile lateral approach (ELA) for treatment of closed displaced intra-articular calcaneal fractures (DIACF) is still being debated. A thorough research was carried out in the MEDLINE, EMBASE and Cochrane library databases from inception to December 2016. Only prospective or retrospective comparative studies were selected in this meta-analysis. Two independent reviewers conducted literature search, data extraction and quality assessment. The primary outcomes were anatomical restoration and prevalence of complications. Secondary outcomes included operation time and functional recovery. Four randomized controlled trials involving 326 patients and three cohort studies involving 206 patients were included. STA technique for DIACFs led to a decline in both operation time and incidence of complications. There were no significant differences between the groups in American Orthopedic Foot and Ankle Society scores, nor changes in Böhler angle. This meta-analysis suggests that STA technique may reduce the operation time and incidence of complications. In conclusion, STA technique is reasonably an optimal choice for DIACF. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Fast Determination of Distribution-Connected PV Impacts Using a Variable Time-Step Quasi-Static Time-Series Approach: Preprint

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

Mather, Barry

The increasing deployment of distribution-connected photovoltaic (DPV) systems requires utilities to complete complex interconnection studies. Relatively simple interconnection study methods worked well for low penetrations of photovoltaic systems, but more complicated quasi-static time-series (QSTS) analysis is required to make better interconnection decisions as DPV penetration levels increase. Tools and methods must be developed to support this. This paper presents a variable-time-step solver for QSTS analysis that significantly shortens the computational time and effort to complete a detailed analysis of the operation of a distribution circuit with many DPV systems. Specifically, it demonstrates that the proposed variable-time-step solver can reduce themore » required computational time by as much as 84% without introducing any important errors to metrics, such as the highest and lowest voltage occurring on the feeder, number of voltage regulator tap operations, and total amount of losses realized in the distribution circuit during a 1-yr period. Further improvement in computational speed is possible with the introduction of only modest errors in these metrics, such as a 91 percent reduction with less than 5 percent error when predicting voltage regulator operations.« less

Cost/benefit tradeoffs for reducing the energy consumption of the commercial air transportation system. Volume 1: Technical analysis

NASA Technical Reports Server (NTRS)

Kraus, E. F.

1976-01-01

The effectiveness and associated costs of operational and technical options for reduced fuel consumption by Douglas aircraft in the domestic airline fleet are assessed. Areas explored include alternative procedures for airline and flight operations, advanced and state of the art technology, modification and derivative configurations, new near-term aircraft, turboprop configuration studies, and optimum aircraft geometry. Data for each aircraft studied is presented in tables and graphs.

Studies to design and develop improved remote manipulator systems

NASA Technical Reports Server (NTRS)

Hill, J. W.; Sword, A. J.

1973-01-01

Remote manipulator control considered is based on several levels of automatic supervision which derives manipulator commands from an analysis of sensor states and task requirements. Principle sensors are manipulator joint position, tactile, and currents. The tactile sensor states can be displayed visually in perspective or replicated in the operator's control handle of perceived by the automatic supervisor. Studies are reported on control organization, operator performance and system performance measures. Unusual hardware and software details are described.

Data Quality and Reliability Analysis of U.S. Marine Corps Ground Vehicle Maintenance Records

DTIC Science & Technology

2015-06-01

Corporation conducted a study on data quality issues present in U. S. Army logistics data ( Galway & Hanks, 1996). The study breaks data issues into three...categories: operational, conceptual, and organizational problems ( Galway & Hanks, 1996). Operational data problems relate to the number of missing or...codes (EIC) are left blank ( Galway & Hanks, 1996, p. 26). Missing entries are attributed to an assumed lack of significance of the EIC. The issue is

Features of Synchronous Electronically Commutated Motors in Servomotor Operation Modes

NASA Astrophysics Data System (ADS)

Dirba, J.; Lavrinovicha, L.; Dobriyan, R.

2017-04-01

The authors consider the features and operation specifics of the synchronous permanent magnet motors and the synchronous reluctance motors with electronic commutation in servomotor operation modes. Calculation results show that mechanical and control characteristics of studied motors are close to a linear shape. The studied motor control is proposed to implement similar to phase control of induction servomotor; it means that angle θ (angle between vectors of the supply voltage and non-load electromotive force) or angle ɛ (angle between rotor direct axis and armature magnetomotive force axis) is changed. The analysis results show that synchronous electronically commutated motors could be used as servomotors.

Manned geosynchronous mission requirements and systems analysis study extension

NASA Technical Reports Server (NTRS)

1981-01-01

Turnaround requirements for the manned orbital transfer vehicle (MOTV) baseline and alternate concepts with and without a space operations center (SOC) are defined. Manned orbital transfer vehicle maintenance, refurbishment, resupply, and refueling are considered as well as the most effective combination of ground based and space based turnaround activities. Ground and flight operations requirements for abort are identified as well as low cost approaches to space and ground operations through maintenance and missions sensitivity studies. The recommended turnaround mix shows that space basing MOTV at SOC with periodic return to ground for overhaul results in minimum recurring costs. A pressurized hangar at SOC reduces labor costs by approximately 50%.

Prognostic Value of Pre-operative Renal Insufficiency in Urothelial Carcinoma: A Systematic Review and Meta-Analysis.

PubMed

Cao, Jian; Zhao, Xiaokun; Zhong, Zhaohui; Zhang, Lei; Zhu, Xuan; Xu, Ran

2016-10-11

The effect of pre-operative renal insufficiency on urothelial carcinoma (UC) prognosis has been investigated by numerous studies. While the majority report worse UC outcomes in patients with renal insufficiency, the results between the studies differed wildly. To enable us to better estimate the prognostic value of renal insufficiency on UC, we performed a systematic review and meta-analysis based on the published literature. A total of 16 studies which involved 5,232 patients with UC, investigated the relationship between pre-operative renal insufficiency and disease prognosis. Estimates of combined hazard ratio (HR) for bladder urothelial carcinoma recurrence, cancer-specific survival (CSS) and overall survival (OS) were 1.65 (95% CI, 1.11-2.19), 1.59 (95% CI, 1.14-2.05) and 1.45 (95% CI, 1.19-1.71), respectively; and for upper urinary tract urothelial carcinoma recurrence, CSS and OS were 2.27 (95% CI, 1.42-3.12), 1.02 (95% CI, 0.47-1.57) and 1.52 (95% CI, 1.05-1.99), respectively. Our results indicate that UC patients with pre-operative renal insufficiency tend to have higher recurrence rates and poorer survival compared to those with clinically normal renal function, thus renal function should be closely monitored in these patients. The impact of intervention for renal insufficiency on the prognosis of UC needs to be further studied.

Work Domain Analysis of a Predecessor Sodium-cooled Reactor as Baseline for AdvSMR Operational Concepts

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

Ronald Farris; David Gertman; Jacques Hugo

This report presents the results of the Work Domain Analysis for the Experimental Breeder Reactor (EBR-II). This is part of the phase of the research designed to incorporate Cognitive Work Analysis in the development of a framework for the formalization of an Operational Concept (OpsCon) for Advanced Small Modular Reactors (AdvSMRs). For a new AdvSMR design, information obtained through Cognitive Work Analysis, combined with human performance criteria, can and should be used in during the operational phase of a plant to assess the crew performance aspects associated with identified AdvSMR operational concepts. The main objective of this phase was tomore » develop an analytical and descriptive framework that will help systems and human factors engineers to understand the design and operational requirements of the emerging generation of small, advanced, multi-modular reactors. Using EBR-II as a predecessor to emerging sodium-cooled reactor designs required the application of a method suitable to the structured and systematic analysis of the plant to assist in identifying key features of the work associated with it and to clarify the operational and other constraints. The analysis included the identification and description of operating scenarios that were considered characteristic of this type of nuclear power plant. This is an invaluable aspect of Operational Concept development since it typically reveals aspects of future plant configurations that will have an impact on operations. These include, for example, the effect of core design, different coolants, reactor-to-power conversion unit ratios, modular plant layout, modular versus central control rooms, plant siting, and many more. Multi-modular plants in particular are expected to have a significant impact on overall OpsCon in general, and human performance in particular. To support unconventional modes of operation, the modern control room of a multi-module plant would typically require advanced HSIs that would provide sophisticated operational information visualization, coupled with adaptive automation schemes and operator support systems to reduce complexity. These all have to be mapped at some point to human performance requirements. The EBR-II results will be used as a baseline that will be extrapolated in the extended Cognitive Work Analysis phase to the analysis of a selected advanced sodium-cooled SMR design as a way to establish non-conventional operational concepts. The Work Domain Analysis results achieved during this phase have not only established an organizing and analytical framework for describing existing sociotechnical systems, but have also indicated that the method is particularly suited to the analysis of prospective and immature designs. The results of the EBR-II Work Domain Analysis have indicated that the methodology is scientifically sound and generalizable to any operating environment.« less

Study on the steady operating state of a micro-pulse electron gun

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

Kui, Zhou; Xing, Luo; Institute of Applied Electronics, Chinese Academy of Engineering Physics, Mianyang 621900

Micro-pulse electron gun (MPG) employs the basic concept of multipacting to produce high-current and short-pulse electron beams from a radio-frequency (RF) cavity. The concept of MPG has been proposed for more than two decades. However, the unstable operating state of MPG vastly obstructs its practical applications. This paper presents a study on the steady operating state of a micro-pulse electron gun with theory and experiments. The requirements for the steady operating state are proposed through the analysis of the interaction between the RF cavity and the beam load. Accordingly, a MPG cavity with the frequency of 2856 MHz has been designed,more » constructed, and tested. Some primary experiments have been finished. Both the unstable and stable operating states of the MPG have been observed. The stable output beam current has been detected at about 3.8 mA. Further experimental study is under way now.« less

An analysis of post-traumatic stress symptoms in United States Air Force drone operators.

PubMed

Chappelle, Wayne; Goodman, Tanya; Reardon, Laura; Thompson, William

2014-06-01

Remotely piloted aircraft (RPA), commonly referred to as "drones," have emerged over the past decade as an innovative warfighting tool. Given there is a paucity of empirical research assessing drone operators, the purpose of this study was to assess for the prevalence of PTSD symptoms among this cohort. Of the 1084 United States Air Force (USAF) drone operators that participated, a total of 4.3% endorsed a pattern of symptoms of moderate to extreme level of severity meeting criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders-4th edition. The incidence of PTSD among USAF drone operators in this study was lower than rates of PTSD (10-18%) among military personnel returning from deployment but higher than incidence rates (less than 1%) of USAF drone operators reported in electronic medical records. Although low PTSD rates may be promising, limitations to this study are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Study of selected tether applications in space, phase 3, volume 2

NASA Technical Reports Server (NTRS)

1986-01-01

The results of a Phase 3 study of two Selected Tether Applications in Space (STAIS); deorbit of a Shuttle and launch of an Orbital Transfer Vehicle (OTV), both from the space station using a tether were examined. The study objectives were to: perform a preliminary engineering design, define operational scenarios, develop a common cost model, perform cost benefits analyses, and develop a Work Breakdown Structure (WBS). Key features of the performance analysis were to identify the net increases in effective Shuttle cargo capability if tethers are used to assist in the deorbit of Shuttles and the launching of the OTVs from the space station and to define deployer system designs required to accomplish these tasks. Deployer concepts were designed and discussed. Operational scenarios, including timelines, for both tethered and nontethered Shuttle and OTV operations at the space station were evaluated. A summary discussion of the Selected Tether Applications Cost Model (STACOM) and the results of the cost benefits analysis are presented. Several critical technologies needed to implement tether assisted deployment of payloads are also discussed. Conclusions and recommendations are presented.

14 CFR 417.405 - Ground safety analysis.

Code of Federal Regulations, 2011 CFR

2011-01-01

... hazard from affecting the public. A launch operator must incorporate the launch site operator's systems... personnel who are knowledgeable of launch vehicle systems, launch processing, ground systems, operations...) Begin a ground safety analysis by identifying the systems and operations to be analyzed; (2) Define the...

14 CFR 417.405 - Ground safety analysis.

Code of Federal Regulations, 2010 CFR

2010-01-01

... hazard from affecting the public. A launch operator must incorporate the launch site operator's systems... personnel who are knowledgeable of launch vehicle systems, launch processing, ground systems, operations...) Begin a ground safety analysis by identifying the systems and operations to be analyzed; (2) Define the...

An analysis of runway-taxiway transgressions at controlled airports

DOT National Transportation Integrated Search

1981-04-01

The purpose of this study was to determine the cause of aircraft making inadvertent or unauthorized takeoffs and transgressions onto active runways during takeoff and landing operations. The study was conducted in four phases: (1) Prior studies by FA...

Lightning Initiation Forecasting: An Operational Dual-Polarimetric Radar Technique

NASA Technical Reports Server (NTRS)

Woodard, Crystal J.; Carey, L. D.; Petersen, W. A.; Roeder, W. P.

2011-01-01

The objective of this NASA MSFC and NOAA CSTAR funded study is to develop and test operational forecast algorithms for the prediction of lightning initiation utilizing the C-band dual-polarimetric radar, UAHuntsville's Advanced Radar for Meteorological and Operational Research (ARMOR). Although there is a rich research history of radar signatures associated with lightning initiation, few studies have utilized dual-polarimetric radar signatures (e.g., Z(sub dr) columns) and capabilities (e.g., fuzzy-logic particle identification [PID] of precipitation ice) in an operational algorithm for first flash forecasting. The specific goal of this study is to develop and test polarimetric techniques that enhance the performance of current operational radar reflectivity based first flash algorithms. Improving lightning watch and warning performance will positively impact personnel safety in both work and leisure environments. Advanced warnings can provide space shuttle launch managers time to respond appropriately to secure equipment and personnel, while they can also provide appropriate warnings for spectators and players of leisure sporting events to seek safe shelter. Through the analysis of eight case dates, consisting of 35 pulse-type thunderstorms and 20 non-thunderstorm case studies, lightning initiation forecast techniques were developed and tested. The hypothesis is that the additional dual-polarimetric information could potentially reduce false alarms while maintaining high probability of detection and increasing lead-time for the prediction of the first lightning flash relative to reflectivity-only based techniques. To test the hypothesis, various physically-based techniques using polarimetric variables and/or PID categories, which are strongly correlated to initial storm electrification (e.g., large precipitation ice production via drop freezing), were benchmarked against the operational reflectivity-only based approaches to find the best compromise between forecast skill and lead-time. Forecast skill is determined by statistical analysis of probability of detection (POD), false alarm ratio (FAR), Operational Utility Index (OUI), and critical success index (CSI).

Surgical treatment of chronic pancreatitis and its complications. Comparative analysis of results in 91 patients.

PubMed

Marinov, V; Draganov, K; Gaydarski, R; Katev, N N

2013-01-01

There is a large variety of proposed conservative, invasive, endoscopic and surgical methods for treatment of chronic pancreatitis and its complications. This study presents a comparative analysis of the results from each group of patients subjected to drainage, resection, denervation and other operative techniques for a total of 91 patients with chronic pancreatitis and its complications. Drainage and resection operative techniques yield comparable results in terms of postoperative pain control 93.1% and 100%, perioperative mortality--3.17% and 5.8%, perioperative morbidity--7.9% and 11.7%, respectively. There is a significant increase in the instances of diabetes in the resection group. Right-side semilunar ganglionectomy is a good method for pain control as an accompanying procedure in the course of another main operative technique.

Analysis of performance losses of direct ethanol fuel cells with the aid of a reference electrode

NASA Astrophysics Data System (ADS)

Li, Guangchun; Pickup, Peter G.

The performances of direct ethanol fuel cells with different anode catalysts, different ethanol concentrations, and at different operating temperatures have been studied. The performance losses of the cell have been separated into individual electrode performance losses with the aid of a reference electrode, ethanol crossover has been quantified, and CO 2 and acetic acid production have been measured by titration. It has been shown that the cell performance strongly depends on the anode catalyst, ethanol concentration, and operating temperature. It was found that the cathode and anode exhibit different dependences on ethanol concentration and operating temperature. The performance of the cathode is very sensitive to the rate of ethanol crossover. Product analysis provides insights into the mechanisms of electro-oxidation of ethanol.

NASTRAN: User's Experiences

NASA Technical Reports Server (NTRS)

1976-01-01

The application of NASTRAN to a wide variety of static and dynamic structural problems is discussed. The following topics are focused upon: (1) methods of analysis; (2) hydroelastic methods; (3) complete analysis of structures; (4) elements and material studies; (5) critical comparisons with other programs; and (6) pre- and post-processor operations.

BRST-BFV analysis of anomalies in bosonic string theory interacting with background gravitational field

NASA Astrophysics Data System (ADS)

Buchbinder, I. L.; Mistchuk, B. R.; Pershin, V. D.

1995-02-01

A general BRST-BFV analysis of the anomaly in string theory coupled to background fields is carried out. An exact equation for the c-valued symbol of the anomaly operator is found and the structure of its solution is studied.

Electric Sector Integration | Energy Analysis | NREL

Science.gov Websites

investigates the potential impacts of expanding renewable technology deployment on grid operations and Electric System Flexibility and Storage Impacts on Conventional Generators Transmission Infrastructure Generation Our grid integration studies use state-of-the-art modeling and analysis to evaluate the impacts of

Specialized data analysis for the Space Shuttle Main Engine and diagnostic evaluation of advanced propulsion system components

NASA Technical Reports Server (NTRS)

1993-01-01

The Marshall Space Flight Center is responsible for the development and management of advanced launch vehicle propulsion systems, including the Space Shuttle Main Engine (SSME), which is presently operational, and the Space Transportation Main Engine (STME) under development. The SSME's provide high performance within stringent constraints on size, weight, and reliability. Based on operational experience, continuous design improvement is in progress to enhance system durability and reliability. Specialized data analysis and interpretation is required in support of SSME and advanced propulsion system diagnostic evaluations. Comprehensive evaluation of the dynamic measurements obtained from test and flight operations is necessary to provide timely assessment of the vibrational characteristics indicating the operational status of turbomachinery and other critical engine components. Efficient performance of this effort is critical due to the significant impact of dynamic evaluation results on ground test and launch schedules, and requires direct familiarity with SSME and derivative systems, test data acquisition, and diagnostic software. Detailed analysis and evaluation of dynamic measurements obtained during SSME and advanced system ground test and flight operations was performed including analytical/statistical assessment of component dynamic behavior, and the development and implementation of analytical/statistical models to efficiently define nominal component dynamic characteristics, detect anomalous behavior, and assess machinery operational condition. In addition, the SSME and J-2 data will be applied to develop vibroacoustic environments for advanced propulsion system components, as required. This study will provide timely assessment of engine component operational status, identify probable causes of malfunction, and indicate feasible engineering solutions. This contract will be performed through accomplishment of negotiated task orders.

Analysis of a Rocket Based Combined Cycle Engine during Rocket Only Operation

NASA Technical Reports Server (NTRS)

Smith, T. D.; Steffen, C. J., Jr.; Yungster, S.; Keller, D. J.

1998-01-01

The all rocket mode of operation is a critical factor in the overall performance of a rocket based combined cycle (RBCC) vehicle. However, outside of performing experiments or a full three dimensional analysis, there are no first order parametric models to estimate performance. As a result, an axisymmetric RBCC engine was used to analytically determine specific impulse efficiency values based upon both full flow and gas generator configurations. Design of experiments methodology was used to construct a test matrix and statistical regression analysis was used to build parametric models. The main parameters investigated in this study were: rocket chamber pressure, rocket exit area ratio, percent of injected secondary flow, mixer-ejector inlet area, mixer-ejector area ratio, and mixer-ejector length-to-inject diameter ratio. A perfect gas computational fluid dynamics analysis was performed to obtain values of vacuum specific impulse. Statistical regression analysis was performed based on both full flow and gas generator engine cycles. Results were also found to be dependent upon the entire cycle assumptions. The statistical regression analysis determined that there were five significant linear effects, six interactions, and one second-order effect. Two parametric models were created to provide performance assessments of an RBCC engine in the all rocket mode of operation.

Reliability of skeletal maturity analysis using the cervical vertebrae maturation method on dedicated software.

PubMed

Padalino, Saverio; Sfondrini, Maria Francesca; Chenuil, Laura; Scudeller, Luigia; Gandini, Paola

2014-12-01

The aim of this study was to assess the feasibility of skeletal maturation analysis using the Cervical Vertebrae Maturation (CVM) method by means of dedicated software, developed in collaboration with Outside Format (Paullo-Milan), as compared with manual analysis. From a sample of patients aged 7-21 years, we gathered 100 lateral cephalograms, 20 for each of the five CVM stages. For each cephalogram, we traced cervical vertebrae C2, C3 and C4 by hand using a lead pencil and an acetate sheet and dedicated software. All the tracings were made by an experienced operator (a dentofacial orthopedics resident) and by an inexperienced operator (a student in dental surgery). Each operator recorded the time needed to make each tracing in order to demonstrate differences in the times taken. Concordance between the manual analysis and the analysis performed using the dedicated software was 94% for the resident and 93% for the student. Interobserver concordance was 99%. The hand-tracing was quicker than that performed by means of the software (28 seconds more on average). The cervical vertebrae analysis software offers excellent clinical performance, even if the method takes longer than the manual technique. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Individual Differences in Human Reliability Analysis

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

Jeffrey C. Joe; Ronald L. Boring

2014-06-01

While human reliability analysis (HRA) methods include uncertainty in quantification, the nominal model of human error in HRA typically assumes that operator performance does not vary significantly when they are given the same initiating event, indicators, procedures, and training, and that any differences in operator performance are simply aleatory (i.e., random). While this assumption generally holds true when performing routine actions, variability in operator response has been observed in multiple studies, especially in complex situations that go beyond training and procedures. As such, complexity can lead to differences in operator performance (e.g., operator understanding and decision-making). Furthermore, psychological research hasmore » shown that there are a number of known antecedents (i.e., attributable causes) that consistently contribute to observable and systematically measurable (i.e., not random) differences in behavior. This paper reviews examples of individual differences taken from operational experience and the psychological literature. The impact of these differences in human behavior and their implications for HRA are then discussed. We propose that individual differences should not be treated as aleatory, but rather as epistemic. Ultimately, by understanding the sources of individual differences, it is possible to remove some epistemic uncertainty from analyses.« less

Initial 12-h operative fluid volume is an independent risk factor for pleural effusion after hepatectomy.

PubMed

Cheng, Xiang; Wu, Jia-Wei; Sun, Ping; Song, Zi-Fang; Zheng, Qi-Chang

2016-12-01

Pleural effusion after hepatectomy is associated with significant morbidity and prolonged hospital stays. Several studies have addressed the risk factors for postoperative pleural effusion. However, there are no researches concerning the role of the initial 12-h operative fluid volume. The aim of this study was to evaluate whether the initial 12-h operative fluid volume during liver resection is an independent risk factor for pleural effusion after hepatectomy. In this study, we retrospectively analyzed clinical data of 470 patients consecutively undergoing elective hepatectomy between January 2011 and December 2012. We prospectively collected and retrospectively analyzed baseline and clinical data, including preoperative, intraoperative, and postoperative variables. Univariate and multivariate analyses were carried out to identify whether the initial 12-h operative fluid volume was an independent risk factor for pleural effusion after hepatectomy. The multivariate analysis identified 2 independent risk factors for pleural effusion: operative time [odds ratio (OR)=10.2] and initial 12-h operative fluid volume (OR=1.0003). Threshold effect analyses revealed that the initial 12 h operative fluid volume was positively correlated with the incidence of pleural effusion when the initial 12-h operative fluid volume exceeded 4636 mL. We conclude that the initial 12-h operative fluid volume during liver resection and operative time are independent risk factors for pleural effusion after hepatectomy. Perioperative intravenous fluids should be restricted properly.

Parametric estimates for the receiver operating characteristic curve generalization for non-monotone relationships.

PubMed

Martínez-Camblor, Pablo; Pardo-Fernández, Juan C

2017-01-01

Diagnostic procedures are based on establishing certain conditions and then checking if those conditions are satisfied by a given individual. When the diagnostic procedure is based on a continuous marker, this is equivalent to fix a region or classification subset and then check if the observed value of the marker belongs to that region. Receiver operating characteristic curve is a valuable and popular tool to study and compare the diagnostic ability of a given marker. Besides, the area under the receiver operating characteristic curve is frequently used as an index of the global discrimination ability. This paper revises and widens the scope of the receiver operating characteristic curve definition by setting the classification subsets in which the final decision is based in the spotlight of the analysis. We revise the definition of the receiver operating characteristic curve in terms of particular classes of classification subsets and then focus on a receiver operating characteristic curve generalization for situations in which both low and high values of the marker are associated with more probability of having the studied characteristic. Parametric and non-parametric estimators of the receiver operating characteristic curve generalization are investigated. Monte Carlo studies and real data examples illustrate their practical performance.

Aspirin Use Prior to Coronary Artery Bypass Grafting Surgery: a Systematic Review.

PubMed

Elbadawi, Ayman; Saad, Marwan; Nairooz, Ramez

2017-02-01

Aspirin use before coronary artery bypass graft (CABG) surgery has been a puzzling question for years. Controversy existed regarding the overall benefits vs. risk of pre-operative aspirin use and was translated to conflicting guidelines from major societies. Observational studies have suggested a reduced mortality with pre-operative aspirin use. A meta-analysis of randomized controlled trials showed increased risk of post-operative bleeding with aspirin, with no associated increased mortality risk. A recent large randomized controlled trial did not find a significant difference in bleeding risk or post-operative mortality with pre-CABG aspirin use. The results of available studies showed a beneficial effect with pre-CABG aspirin use by decreasing thrombotic complications and perioperative myocardial infarction, with an associated adverse risk of bleeding that did not affect mortality rates. Given overall benefit-risk assessment, we are in favor of pre-operative aspirin use in CABG patients.

Measuring the operational efficiency of individual theme park attractions.

PubMed

Kim, Changhee; Kim, Soowook

2016-01-01

This study assesses the operation efficiency of theme park attractions using the data envelopment analysis, utilizing actual data on 15 attractions at Samsung Everland located in Yongin-si, Republic of Korea. In particular, this study identifies crowding and waiting time as one of the main causes of visitor's satisfaction, and analyzes the efficiency of individual attractions in terms of waiting time. The installation area, installation cost, and annual repair cost are set as input factors and the number of annual users and customer satisfaction as output factors. The results show that the roller coaster-type attractions were less efficient than other types of attractions while rotating-type attractions were relatively more efficient. However, an importance performance analysis on individual attraction's efficiency and satisfaction showed that operational efficiency should not be the sole consideration in attraction installation. In addition, the projection points for input factors for efficient use of attractions and the appropriate reference set for benchmarking are provided as guideline for attraction efficiency management.

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING THE DOUBLE-BUNDLE TECHNIQUE – EVALUATION IN THE BIOMECHANICS LABORATORY

PubMed Central

D'Elia, Caio Oliveira; Bitar, Alexandre Carneiro; Castropil, Wagner; Garofo, Antônio Guilherme Padovani; Cantuária, Anita Lopes; Orselli, Maria Isabel Veras; Luques, Isabela Ugo; Duarte, Marcos

2015-01-01

Objective: The objective of this study was to describe the methodology of knee rotation analysis using biomechanics laboratory instruments and to present the preliminary results from a comparative study on patients who underwent anterior cruciate ligament (ACL) reconstruction using the double-bundle technique. Methods: The protocol currently used in our laboratory was described. Three-dimensional kinematic analysis was performed and knee rotation amplitude was measured on eight normal patients (control group) and 12 patients who were operated using the double-bundle technique, by means of three tasks in the biomechanics laboratory. Results: No significant differences between operated and non-operated sides were shown in relation to the mean amplitudes of gait, gait with change in direction or gait with change in direction when going down stairs (p > 0.13). Conclusion: The preliminary results did not show any difference in the double-bundle ACL reconstruction technique in relation to the contralateral side and the control group. PMID:27027003

Clinical evaluation of post-operative cerebral infarction in traumatic epidural haematoma.

PubMed

Zhang, Suojun; Wang, Sheng; Wan, Xueyan; Liu, Shengwen; Shu, Kai; Lei, Ting

2017-01-01

Patients with traumatic epidural haematoma, undergoing the prompt and correct treatment, usually have favourable outcomes. However, secondary cerebral infarction may be life-threatening condition, as it is difficult to be identified before neurological impairment occurs. To evaluate the clinical data of patients with traumatic EDH and assess potential risk factors for post-operative cerebral infarction. The clinical data of patients with traumatic EDH were collected and analysed retrospectively. The univariate analysis revealed 10 potential risk factors (the haematoma location, volume, the largest thickness and mid-line shift, basal cisterns compression, traumatic subarachnoid haemorrhage, pupil dilatation, pre-operative Glasgow Coma Scale score, ∆GCS and intraoperative brain pressure) for cerebral infarction with statistically significant difference. Of these factors, haematoma volume and basal cistern compression turned out to be the most significant risk factors through final multivariate logistic regression analysis. The findings of this study can provide predictive factors for development of cerebral infarction and information for clinical decision-making and future studies.

[An analysis of appeals against the ruling of the occupational physician's lodged to the Department of Prevention and Safety in the Working Environment--Health Prevention and Occupational Epidemiology Operative Unit within the A.S.P. Palermo (Palermo Health Authority), years 2008-2010].

PubMed

Marsala, M G L; Morici, M; Lacca, G; Curcurù, L; Eduardo, E Costagliola; Ilardo, S; Trapani, E; Caracausi, R; Firenze, A

2012-01-01

The purpose of this study is to analyze the appeals against a "suitability judgment for work" lodged to the U.O.S. "Health Prevention and Occupational Epidemiology Operative Unit" of Department of Prevention and Safety in the Working Environment within the ASP Palermo (U.O.S.), from 2008 to 2010. Studying the appeals gives an indirect view on the occupational physician activity and allows to monitor their actions, analysis aims at highlighting those issues around which any planning and implementation of coordination activities should be focused.

Applied virtual reality in aerospace design

NASA Technical Reports Server (NTRS)

Hale, Joseph P.

1995-01-01

A virtual reality (VR) applications program has been under development at the Marshall Space Flight Center (MSFC) since 1989. The objectives of the MSFC VR Applications Program are to develop, assess, validate, and utilize VR in hardware development, operations development and support, mission operations training and science training. Before VR can be used with confidence in a particular application, VR must be validated for that class of applications. For that reason, specific validation studies for selected classes of applications have been proposed and are currently underway. These include macro-ergonomic 'control room class' design analysis, Spacelab stowage reconfiguration training, a full-body microgravity functional reach simulator, a gross anatomy teaching simulator, and micro-ergonomic design analysis. This paper describes the MSFC VR Applications Program and the validation studies.

Condensate polisher prefiltration study for Laguna Verde Station

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

Garcia, A.; Oyen, L.C.; Nelson, R.A.

1995-05-01

This paper describes an analysis of the iron and copper in the condensate and the technical and economic assessment of the installation of condensate polisher prefilters in Comision Federal de Electricidad`s Laguna Verde Nuclear Generating Station (LVNGS) north of Veracruz, Mexico. LVNGS is a 654 MWe General Electric BWR plant; Unit 1 has been in commercial operation since July, 1990, and Unit 2 is scheduled to become operational in June, 1995. The primary purpose of this study was to (1) analyze the high iron and copper concentrations in the condensate and feedwater, (2) identify, assess, and evaluate techniques to reducemore » the iron and copper concentrations, and (3) perform a cost-benefit analysis of the installation of implementing the appropriate techniques.« less

Cognitive Task Analysis of the HALIFAX-Class Operations Room Officer

DTIC Science & Technology

1999-03-10

Image Cover Sheet CLASSIFICATION SYSTEM NUMBER 510918 UNCLASSIFIED llllllllllllllllllllllllllllllllllllllll TITLE COGNITIVE TASK ANALYSIS OF THE...DATES COVERED 00-00-1999 to 00-00-1999 4. TITLE AND SUBTITLE Cognitive Task Analysis of the HALIFAX-Class Operations Room Officer 5a. CONTRACT...Ontario . ~ -- . ’ c ... - Incorporated Cognitive Task Analysis of the HALIFAX-Class Operations Room Officer: PWGSC Contract No. W7711-7-7404/001/SV