NASA aviation safety reporting system
NASA Technical Reports Server (NTRS)
1978-01-01
The study deals with 165 inadvertent operations on or into inappropriate portions of the aircraft areas at controlled airports. Pilot-initiated and controller-initiated incursions are described and discussed. It was found that a majority of the pilot-initiated occurrences involved operation without a clearance; controller-initiated occurrences usually involved failure to maintain assured separation. The factors associated with these occurrences are analyzed. It appears that a major problem in these occurrences is inadequate coordination among the various system participants. Reasons for this, and some possible solutions to various aspects of the problem, are discussed. A sample of reports from pilots and controllers is presented. These relate to undesired occurrences in air transport, general aviation, and air traffic control operations; to ATC coordination problems; and to a recurrent problem in ASRS reports, parachuting operations. A sample of alert bulletins and responses to them is presented.
Cognitive Development, Genetics Problem Solving, and Genetics Instruction: A Critical Review.
ERIC Educational Resources Information Center
Smith, Mike U.; Sims, O. Suthern, Jr.
1992-01-01
Review of literature concerning problem solving in genetics and Piagetian stage theory. Authors conclude the research suggests that formal-operational thought is not strictly required for the solution of the majority of classical genetics problems; however, some genetic concepts are difficult for concrete operational students to understand.…
NASA Technical Reports Server (NTRS)
Waldrop, Glen S.
1990-01-01
Operations problems and cost drivers were identified for current propulsion systems and design and technology approaches were identified to increase the operational efficiency and to reduce operations costs for future propulsion systems. To provide readily usable data for the ALS program, the results of the OEPSS study were organized into a series of OEPSS Data Books. This volume presents a detailed description of 25 major problems encountered during launch processing of current expendable and reusable launch vehicles. A concise description of each problem and its operational impact on launch processing is presented, along with potential solutions and technology recommendation.
Challenges in building intelligent systems for space mission operations
NASA Technical Reports Server (NTRS)
Hartman, Wayne
1991-01-01
The purpose here is to provide a top-level look at the stewardship functions performed in space operations, and to identify the major issues and challenges that must be addressed to build intelligent systems that can realistically support operations functions. The focus is on decision support activities involving monitoring, state assessment, goal generation, plan generation, and plan execution. The bottom line is that problem solving in the space operations domain is a very complex process. A variety of knowledge constructs, representations, and reasoning processes are necessary to support effective human problem solving. Emulating these kinds of capabilities in intelligent systems offers major technical challenges that the artificial intelligence community is only beginning to address.
Automated Turn-Key Systems in the Library: Prospects and Perils
ERIC Educational Resources Information Center
Brownrigg, Edwin Blake; Bruer, J. Michael
1976-01-01
Problems, issues, and alternatives in designing individual, stand alone systems for servicing selected library operations, with emphasis on problems of integrating these with major automated systems, a new mode of operation called coupling, and strategies for dealing with large amounts of retrospective data. (Author/LS)
Modal Analysis for Grid Operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
MANGO software is to provide a solution for improving small signal stability of power systems through adjusting operator-controllable variables using PMU measurement. System oscillation problems are one of the major threats to the grid stability and reliability in California and the Western Interconnection. These problems result in power fluctuations, lower grid operation efficiency, and may even lead to large-scale grid breakup and outages. This MANGO software aims to solve this problem by automatically generating recommended operation procedures termed Modal Analysis for Grid Operation (MANGO) to improve damping of inter-area oscillation modes. The MANGO procedure includes three steps: recognizing small signalmore » stability problems, implementing operating point adjustment using modal sensitivity, and evaluating the effectiveness of the adjustment. The MANGO software package is designed to help implement the MANGO procedure.« less
Automation--planning to implementation; the problems en route.
Pizer, I H
1976-01-01
Once the major decision to automate library processes is made, there are a variety of problems which may be encountered before the planned system becomes operational. These include problems of personnel, budget, procurement of adjunct services, institutional priorities, and manufacturing uncertainties. Actual and potential difficulties are discussed. PMID:1247703
Political and legal implications of developing and operating a satellite power system
NASA Technical Reports Server (NTRS)
Hazelrigg, G. A., Jr.
1977-01-01
A number of political and legal implications of developing and operating a satellite power system (SPS) are identified and studied in this report. These include the vulnerability of SPS to actions of adversaries, communications impacts, the legality of an SPS in orbit including on-orbit military protection, alleviation of political concerns about deployment and operation of SPS, programmatic planning for SPS and the interaction of SPS with federal regulatory agencies and major departments. In comparing SPS to terrestrial power stations, it is seen that the political problems are neither clearly larger nor clearly smaller--they are clearly different and they are international in nature. If SPS is to become a reality these problems must be dealt with. Five major issues are identified. These must be resolved in order to obtain international acceptance of SPS. However, this study has found no insurmountable obstacles that would clearly prohibit the deployment, operation and protection of an SPS fleet.
Improving incident management response and coordination of resources.
DOT National Transportation Integrated Search
2001-12-01
Highway crashes cause a major impact to the transportation network by critically limiting the operational efficiency of the roadway. Traveler delay is the problem most often associated with highway crashes, but by far the most serious problem is the ...
Comfortable with Chaos: Operational Design in the Naval Special Warfare Planning Process
2011-05-08
President Alvaro Uribe Velez took office, Colombia was enduring a multi- faceted and interactively complex strategic situation. Three major insurgent groups...President Uribe took office and designed a comprehensive strategy to tackle the "wicked" problem. President Uribe designed an operational approach that...government -unattainable by previous presidents. From 2002 to 2006, the Uribe administration reframed 19 their understanding of the problem and
CENTRALIZED MANAGEMENT OF SMALL TREATMENT PLANTS USING INSTRUMENTS AND REMOTE ALARMS
The operation and maintenance of small treatment plants and associated lift stations pose unique and difficult problems to the authority responsible for their performance. Due to financial and manpower limitations, they must operate unattended the majority of the time. Undetected...
The Illusory Dichotomy of Plagiarism
ERIC Educational Resources Information Center
Stuhmcke, Anita; Booth, Tracey; Wangmann, Jane
2016-01-01
Plagiarism has been characterised as a "major problem" for universities. While tensions between students and universities are inevitable, the problem with the existing system of plagiarism management and prevention is that it operates to problematise the relationship between the university and the student, rather than address the core…
A Hydraulically Operated Pine Cone Cutter
Carl W. Fatzinger; M.T. Proveaux
1971-01-01
Mature cones of slash pine (Pinus elliottii Engelm. var. elliottii) and longleaf pine (P. palustris Mill.) can be easily bisected along their longitudinal axes with the hydraulic pine cone cutter described. This cutter eliminates the two major problems of earlier models--undue operator fatigue and the...
NASA Technical Reports Server (NTRS)
Gentry, Gregory J.; Reysa, Richard P.; Williams, Dave E.
2004-01-01
The International Space Station continues to build up its life support equipment capability. Several ECLS equipment failures have occurred since Lab activation in February 2001. Major problems occurring between February 2001 and February 2002 were discussed in other works. Major problems occurring between February 2002 and February 2003 are discussed in this paper, as are updates from previously ongoing unresolved problems. This paper addresses failures, and root cause, with particular emphasis on likely micro-gravity causes. Impact to overall station operations and proposed and accomplished fixes will also be discussed.
Cost containment in laundry and linen service.
Ellis, B
1978-03-16
One major problem looms among all others in the area of laundry and linen service, whether a hospital has an in-house operation, is part of a shared or central laundry, or uses a commercial service. That is the costly problem of controling linen consumption and replacement. A recent seminar offers some insight into reasons for the problem and some possible solutions.
Addressing Problems Encountered in Case-Based Teaching
ERIC Educational Resources Information Center
Turgeon, A. J.
2007-01-01
TURF 436 (Case Studies in Turfgrass Management) is the capstone course for turfgrass science majors at the Pennsylvania State University. Students are introduced to problems and complex problematic situations encountered in the management of golf and sports turf and in professional lawn-care operations. Following completion of the orientation case…
Transportation and the Mentally Retarded.
ERIC Educational Resources Information Center
President's Committee on Mental Retardation, Washington, DC.
Reported were the results of a contract that involved identification, description, and categorization of the nature of transportation problems for the mentally retarded by means of analysis of existing studies, two surveys, and an inventory of specialized programs and systems operating in the United States. One major problem was found to be…
NASA Technical Reports Server (NTRS)
Stanley, C. W.; Hood, W. E.
1981-01-01
The U.S. Marine Corp (USMC) has been operating the only V/STOL attack aircraft in the western world since 1971. Some of the maintenance problems experienced are related to the unique V/STOL design criteria of the Pegasus engine. However, the major part of the required maintenance effort is found to involve the more conventional engine problems. A description of the aircraft engine is provided and the problems resulting from V/STOL design demands are examined. Attention is given to the fuel system control, the engine air bleed, foreign object damage to the hp compressor, and the engine exhaust system.
Shuttle Orbiter Active Thermal Control Subsystem design and flight experience
NASA Technical Reports Server (NTRS)
Bond, Timothy A.; Metcalf, Jordan L.; Asuncion, Carmelo
1991-01-01
The paper examines the design of the Space Shuttle Orbiter Active Thermal Control Subsystem (ATCS) constructed for providing the vehicle and payload cooling during all phases of a mission and during ground turnaround operations. The operation of the Shuttle ATCS and some of the problems encountered during the first 39 flights of the Shuttle program are described, with special attention given to the major problems encountered with the degradation of the Freon flow rate on the Orbiter Columbia, the Flash Evaporator Subsystem mission anomalies which occurred on STS-26 and STS-34, and problems encountered with the Ammonia Boiler Subsystem. The causes and the resolutions of these problems are discussed.
Implementation experiences of NASTRAN on CDC CYBER 74 SCOPE 3.4 operating system
NASA Technical Reports Server (NTRS)
Go, J. C.; Hill, R. G.
1973-01-01
The implementation of the NASTRAN system on the CDC CYBER 74 SCOPE 3.4 Operating System is described. The flexibility of the NASTRAN system made it possible to accomplish the change with no major problems. Various sizes of benchmark and test problems, ranging from two hours to less than one minute CP time were run on the CDC CYBER SCOPE 3.3, Univac EXEC-8, and CDC CYBER SCOPE 3.4. The NASTRAN installation deck is provided.
Building a Foundation on Sand: The Demise of Leaders Resulting from Toxic Followership
2016-05-26
Toxic Followers, Prototype Theory, Mission Command, Operational Art , McClellan, Johnston, MacArthur, Powell, 16. SECURITY CLASSIFICATION OF: a. REPORT...structured and more vague problems. Using mission command throughout the Army facilitates leaders practicing operational art .2 Current US joint doctrine...defines operational art as the “use of creative thinking by commanders and staffs to design strategies, campaigns, and major operations and organize
FIRESCOPE: a new concept in multiagency fire suppression coordination
Richard A. Chase
1980-01-01
FIRESCOPE is a system developed to improve the capability of firefighting agencies in southern California in allocating and managing fire suppression resources. The system provides an effective and efficient solution to operational coordination requirements and problems of the major fire protection agencies serving the southern California urban-wildland complex. Major...
Poverty, Ethnic Identity, and Health Care.
ERIC Educational Resources Information Center
Bullough, Bonnie; Bullough, Vern L.
This book tries to present the health care problems of the major ethnic minority groups in perspective. Although poverty is probably the most crucial variable in the genesis of these problems, there are still many subtle and not so subtle forms of discrimination operating in the health field. Unfortunately, discrimination in other aspects of…
A security/safety survey of long term care facilities.
Acorn, Jonathan R
2010-01-01
What are the major security/safety problems of long term care facilities? What steps are being taken by some facilities to mitigate such problems? Answers to these questions can be found in a survey of IAHSS members involved in long term care security conducted for the IAHSS Long Term Care Security Task Force. The survey, the author points out, focuses primarily on long term care facilities operated by hospitals and health systems. However, he believes, it does accurately reflect the security problems most long term facilities face, and presents valuable information on security systems and practices which should be also considered by independent and chain operated facilities.
Hemmelmayr, Vera C.; Cordeau, Jean-François; Crainic, Teodor Gabriel
2012-01-01
In this paper, we propose an adaptive large neighborhood search heuristic for the Two-Echelon Vehicle Routing Problem (2E-VRP) and the Location Routing Problem (LRP). The 2E-VRP arises in two-level transportation systems such as those encountered in the context of city logistics. In such systems, freight arrives at a major terminal and is shipped through intermediate satellite facilities to the final customers. The LRP can be seen as a special case of the 2E-VRP in which vehicle routing is performed only at the second level. We have developed new neighborhood search operators by exploiting the structure of the two problem classes considered and have also adapted existing operators from the literature. The operators are used in a hierarchical scheme reflecting the multi-level nature of the problem. Computational experiments conducted on several sets of instances from the literature show that our algorithm outperforms existing solution methods for the 2E-VRP and achieves excellent results on the LRP. PMID:23483764
Hemmelmayr, Vera C; Cordeau, Jean-François; Crainic, Teodor Gabriel
2012-12-01
In this paper, we propose an adaptive large neighborhood search heuristic for the Two-Echelon Vehicle Routing Problem (2E-VRP) and the Location Routing Problem (LRP). The 2E-VRP arises in two-level transportation systems such as those encountered in the context of city logistics. In such systems, freight arrives at a major terminal and is shipped through intermediate satellite facilities to the final customers. The LRP can be seen as a special case of the 2E-VRP in which vehicle routing is performed only at the second level. We have developed new neighborhood search operators by exploiting the structure of the two problem classes considered and have also adapted existing operators from the literature. The operators are used in a hierarchical scheme reflecting the multi-level nature of the problem. Computational experiments conducted on several sets of instances from the literature show that our algorithm outperforms existing solution methods for the 2E-VRP and achieves excellent results on the LRP.
The operant-respondent distinction: Future directions
Pear, Joseph J.; Eldridge, Gloria D.
1984-01-01
The operant-respondent distinction has provided a major organizing framework for the data generated through the experimental analysis of behavior. Problems have been encountered, however, in using it as an explanatory concept for such phenomena as avoidance and conditioned suppression. Data now exist that do not fit neatly into the framework. Moreover, the discovery of autoshaping has highlighted difficulties in isolating the two types of behavior and conditioning. Despite these problems, the operant-respondent framework remains the most successful paradigm currently available for organizing behavioral data. Research and theoretical efforts should therefore probably be directed to modifying the framework to account for disparate data. PMID:16812402
Mimetic finite difference method
NASA Astrophysics Data System (ADS)
Lipnikov, Konstantin; Manzini, Gianmarco; Shashkov, Mikhail
2014-01-01
The mimetic finite difference (MFD) method mimics fundamental properties of mathematical and physical systems including conservation laws, symmetry and positivity of solutions, duality and self-adjointness of differential operators, and exact mathematical identities of the vector and tensor calculus. This article is the first comprehensive review of the 50-year long history of the mimetic methodology and describes in a systematic way the major mimetic ideas and their relevance to academic and real-life problems. The supporting applications include diffusion, electromagnetics, fluid flow, and Lagrangian hydrodynamics problems. The article provides enough details to build various discrete operators on unstructured polygonal and polyhedral meshes and summarizes the major convergence results for the mimetic approximations. Most of these theoretical results, which are presented here as lemmas, propositions and theorems, are either original or an extension of existing results to a more general formulation using polyhedral meshes. Finally, flexibility and extensibility of the mimetic methodology are shown by deriving higher-order approximations, enforcing discrete maximum principles for diffusion problems, and ensuring the numerical stability for saddle-point systems.
Racism and the Media: Racism in Television
ERIC Educational Resources Information Center
Jones, Marquita
1971-01-01
The major problem confronting black people working in the television industry today is that of communicating with the black community, despite the nature of television and its system of operation. (DM)
Human factors in air traffic control: problems at the interfaces.
Shouksmith, George
2003-10-01
The triangular ISIS model for describing the operation of human factors in complex sociotechnical organisations or systems is applied in this research to a large international air traffic control system. A large sample of senior Air Traffic Controllers were randomly assigned to small focus discussion groups, whose task was to identify problems occurring at the interfaces of the three major human factor components: individual, system impacts, and social. From these discussions, a number of significant interface problems, which could adversely affect the functioning of the Air Traffic Control System, emerged. The majority of these occurred at the Individual-System Impact and Individual-Social interfaces and involved a perceived need for further interface centered training.
Modern techniques and technologies for unbundled access in the local loop
NASA Astrophysics Data System (ADS)
Bacis Vasile, Irina Bristena; Schiopu, Paul; Marghescu, Cristina
2015-02-01
The efficient and unbundled use of the existing telecommunications infrastructure represents a major goal for the development of the services offered by telecommunications providers. A major telecommunications operator can provide services to a subscriber using a copper wire pair or part of the frequency spectrum of a copper wire pair, together with other operators, through a process of unbundling access in the local loop. Since access to the vocal band is an already solved problem, concerns turn to the broadband access with xDSL service delivery on ungrouped subscriber loops; besides the legal and economic aspects involved this has become an engineering problem also. The local loop unbundling methods have a substantial technical impact. This impact should be taken into account right from the design stage and then in the standardization stage of broadband systems intended to operate on copper wire pairs in the local loop. These systems are known under the generic term of xDSL and began to be analyzed in the late 90s. xDSL became the dominant solution for providing Internet at a reasonable price for both residential and business subscribers. In this massive development scenario, certain problems will arise from the early stages of deployment, and another type of problems will occur later on when a large number of systems will be installed in a single beam.
Proposed BMPs for Invasive Plant Mitigation during Timber Harvesting Operations
Chris B. LeDoux; Danielle K. Martin
2013-01-01
The invasion and spread of invasive plants is a major problem in forested ecosystems. Invasive plants can displace existing vegetation and in some cases take over the site. With the displacement of native vegetation come major ecosystem changes that may jeopardize ecological processes and functions as well as habitat for wildlife. The disturbance caused during timber...
New design and operating techniques and requirements for improved aircraft terminal area operations
NASA Technical Reports Server (NTRS)
Reeder, J. P.; Taylor, R. T.; Walsh, T. M.
1974-01-01
Current aircraft operating problems that must be alleviated for future high-density terminal areas are safety, dependence on weather, congestion, energy conservation, noise, and atmospheric pollution. The Microwave Landing System (MLS) under development by FAA provides increased capabilities over the current ILS. The development of the airborne system's capability to take maximum advantage of the MLS capabilities in order to solve terminal area problems are discussed. A major limiting factor in longitudinal spacing for capacity increase is the trailing vortex hazard. Promising methods for causing early dissipation of the vortices were explored. Flight procedures for avoiding the hazard were investigated. Terminal configured vehicles and their flight test development are discussed.
Vector control activities: Fiscal Year, 1986
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1987-04-01
The program is divided into two major components - operations and support studies. The support studies are designed to improve the operational effectiveness and efficiency of the control program and to identify other vector control problems requiring TVA attention and study. Nonchemical methods of control are emphasized and are supplemented with chemical measures as needed. TVA also cooperates with various concerned municipalities in identifying blood-sucking arthropod pest problems and demonstrating control techniques useful in establishing abatement programs, and provides technical assistance to other TVA programs and organizations. The program also helps Land Between The Lakes (LBL) plan and conduct vectormore » control operations and tick control research. Specific program control activities and support studies are discussed.« less
NASA Technical Reports Server (NTRS)
Kiceniuk, T.
1985-01-01
An organic Rankine-cycle (ORC) power module was developed for use in a multimodule solar power plant to be built and operated in a small community. Many successful components and subsystems, including the reciever, power conversion subsystem, energy transport subsystem, and control subsystem, were tested. Tests were performed on a complete power module using a test bed concentrator in place of the proposed concentrator. All major single-module program functional objectives were met and the multimodule operation presented no apparent problems. The hermetically sealed, self-contained, ORC power conversion unit subsequently successfully completed a 300-hour endurance run with no evidence of wear or operating problems.
Battlefield casualties treated at Camp Rhino, Afghanistan: lessons learned.
Bilski, Tracy R; Baker, Bruce C; Grove, Jay R; Hinks, Robert P; Harrison, Michael J; Sabra, John P; Temerlin, Steven M; Rhee, Peter
2003-05-01
Operation Enduring Freedom is an effort to combat terrorism after an attack on the United States. The first large-scale troop movement (> 1,300) was made by the U.S. Marines into the country of Afghanistan by establishing Camp Rhino. Data were entered into a personal computer at Camp Rhino, using combat casualty collecting software. Surgical support at Camp Rhino consisted of two surgical teams (12 personnel each), who set up two operating tables in one tent. During the 6-week period, a total of 46 casualties were treated, and all were a result of blast or blunt injury. One casualty required immediate surgery, two required thoracostomy tube, and the remainder received fracture stabilization or wound care before being transported out of Afghanistan. The casualties received 6 major surgical procedures and 11 minor procedures, which included fracture fixations. There was one killed in action and one expectant patient. The major problem faced was long delay in access to initial surgical care, which was more than 5 hours and 2 hours for two of the casualties. Smaller, more mobile surgical teams will be needed more frequently in future military operations because of inability to set up current larger surgical facilities, and major problems will include long transport times. Future improvements to the system should emphasize casualty evacuation, en-route care, and joint operations planning between services.
National Space Transportation Systems Program mission report
NASA Technical Reports Server (NTRS)
Collins, M. A., Jr.; Aldrich, A. D.; Lunney, G. S.
1984-01-01
The 515-41B National Space Transportation Systems Program Mission Report contains a summary of the major activities and accomplishments of the sixth operational Shuttle flight and fourth flight of the OV-099 vehicle, Challenger. Since this flight was the first to land at Kennedy Space Center, the vehicle was towed directly to the OPF (Orbiter Processing Facility) where preparations for flight STS-41C, scheduled for early April 1984, began immediately. The significant problems that occurred during STS-41B are summarized and a problem tracking list that is a complete list of all problems that occurred during the flight is given. None of the problems will affect the STS 41C flight. The major objectives of flight STS-41B were to successfully deploy the Westar satellite and the Indonesian Communications Satellite-B2 (PALAPA-B2); to evaluate the MMU (Manned Maneuvering Unit) support for EVA (Extravehicular Activities); to exercise the MFR (Manipulator Foot Restraint); to demonstrate a closed loop rendezvous; and to operate the M.R (Monodisperse Latex Reactor), the ACES (Acoustic Containerless Experiment System) and the IEF (Isoelectric Focusing) in cabin experiments; and to obtain photographs with the Cinema 360 Cameras.
Steam generator degradation: Current mitigation strategies for controlling corrosion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Millett, P.
1997-02-01
Steam Generator degradation has caused substantial losses of power generation, resulted in large repair and maintenance costs, and contributed to significant personnel radiation exposures in Pressurized Water Reactors (PWRs) operating throughout the world. EPRI has just published the revised Steam Generator Reference Book, which reviews all of the major forms of SG degradation. This paper discusses the types of SG degradation that have been experienced with emphasis on the mitigation strategies that have been developed and implemented in the field. SG degradation is presented from a world wide perspective as all countries operating PWRs have been effected to one degreemore » or another. The paper is written from a US. perspective where the utility industry is currently undergoing tremendous change as a result of deregulation of the electricity marketplace. Competitive pressures are causing utilities to strive to reduce Operations and Maintenance (O&M) and capital costs. SG corrosion is a major contributor to the O&M costs of PWR plants, and therefore US utilities are evaluating and implementing the most cost effective solutions to their corrosion problems. Mitigation strategies developed over the past few years reflect a trend towards plant specific solutions to SG corrosion problems. Since SG degradation is in most cases an economic problem and not a safety problem, utilities can focus their mitigation strategies on their unique financial situation. Accordingly, the focus of R&D has shifted from the development of more expensive, prescriptive solutions (e.g. reduced impurity limits) to corrosion problems to providing the utilities with a number of cost effective mitigation options (e.g. molar ratio control, boric acid treatment).« less
A Guide to Major Insects, Diseases, Air Pollution, Injury, and Chemical Injury of Sycamore
J.D. Solomon; A. Dan Wilson; N.M. Schiff
1999-01-01
This booklet will help nurserymen, forest woodland managers, pest control operators, and homeowners to identify and control pest problems on sycamore trees. The major insect and disease pests of sycamores in the Eastern United Stats are emphasized. Descriptions and illustrations of the pests and the damage they cause are provided to aid in identification. Brief notes...
Real-time operating system for selected Intel processors
NASA Technical Reports Server (NTRS)
Pool, W. R.
1980-01-01
The rationale for system development is given along with reasons for not using vendor supplied operating systems. Although many system design and performance goals were dictated by problems with vendor supplied systems, other goals surfaced as a result of a design for a custom system able to span multiple projects. System development and management problems and areas that required redesign or major code changes for system implementation are examined as well as the relative successes of the initial projects. A generic description of the actual project is provided and the ongoing support requirements and future plans are discussed.
Soil erosion following forest operations in the Southern Piedmont of central Alabama
Johnny M. Grace
2004-01-01
In recent years, nonpoint source pollution (NPS) has been recognized as one of the major threats to the nation's water quality. Clearly, forest operations such as harvesting and site preparation have the potential to have degrading impacts on forest water quality. However, there exists a gap in the understanding of the nature and extent of NPS pollution problems...
Evaluation of the effect of gate strategies in drayage related emissions.
DOT National Transportation Integrated Search
2013-03-01
Intermodal Marine Container Terminals are experiencing growth in container volumes and are under pressure to : develop strategies to accommodate increasing demand. One of the major factors contributing to the problem is : inefficient gate operations ...
NMESys: An expert system for network fault detection
NASA Technical Reports Server (NTRS)
Nelson, Peter C.; Warpinski, Janet
1991-01-01
The problem of network management is becoming an increasingly difficult and challenging task. It is very common today to find heterogeneous networks consisting of many different types of computers, operating systems, and protocols. The complexity of implementing a network with this many components is difficult enough, while the maintenance of such a network is an even larger problem. A prototype network management expert system, NMESys, implemented in the C Language Integrated Production System (CLIPS). NMESys concentrates on solving some of the critical problems encountered in managing a large network. The major goal of NMESys is to provide a network operator with an expert system tool to quickly and accurately detect hard failures, potential failures, and to minimize or eliminate user down time in a large network.
Nakano, Takumi; Araki, Keijiro; Nakatani, Hajime; Kobayashi, Michiya; Sugimoto, Takeki; Furuya, Yasuo; Matsuoka, Takanori; Jin, Toufeng; Hanazaki, Kazuhiro
2007-04-01
Persistence of postoperative immune dysfunction is a critical problem because it increases the risk of serious infectious complications. The mechanisms of the immune dysfunction that occur initially after non-thermal operative injury remain to be fully elucidated. Two mouse models of operative trauma (simple laparotomy to represent minor operative injury and ileocecal resection to represent major operative injury) were used to define the characteristics of initial cytokine synthesis. Geldanamycin and thalidomide were independently added intraperitoneally before and after operative injury to examine the effect on postoperative immune dysfunction. Mice were sacrificed at scheduled times (3, 6, 12, and 24 h after operative injury) and TNF-alpha, IL-2, IL-4, and IL-10 were analyzed. Spleen was used for intracellular cytokines and RT-PCR. Sera were used for ELISA. Major operative injury caused an initial upregulation of IL-10 synthesis with delayed synthesis of TNF-alpha and IL-2. Minor operative injury caused an early induction of IL-2 synthesis preceded by an initial induction of IL-4 synthesis. GA caused a specific early upregulation of TNF-alpha mRNA expression and intracellular TNF-alpha synthesis. The GA and THD groups showed early serum IL-2 production with reduction of IL-10 mRNA expression and intracellular IL-10 synthesis in the early post-operative phase. Major and minor operative injury showed different Th1/Th2 cytokine patterns in the initial post-operative period. Geldanamycin and thalidomide improved the Th1/Th2 imbalance independently after major operative injury.
The Near-Earth Orbital Debris Problem and the Challenges for Environment Remediation
NASA Technical Reports Server (NTRS)
Liou, Jer-Chyi
2012-01-01
The near-Earth space environment has been gradually polluted with orbital debris (OD) since the beginning of space activities 55 years ago. Although this problem has been known to the research community for decades, the public was, in general, unaware of the issue until the anti-satellite test conducted by China in 2007 and the collision between Cosmos 2251 and the operational Iridium 33 in 2009. The latter also underlined the potential of an ongoing collision cascade effect (the "Kessler Syndrome") in the low Earth orbit (LEO, the region below 2000 km altitude). Recent modeling results have indicated that mitigation measures commonly adopted by the international space community will be insufficient to stabilize the LEO debris population. To better limit the OD population increase, more aggressive actions must be considered. There are three options for OD environment remediation-removal of large/massive intact objects to address the root cause of the OD population growth problem, removal of 5-mm-to-1 cm debris to mitigate the main mission-ending threats for the majority of operational spacecraft, and prevention of major debris-generating collisions as a temporary means to slow down the OD population increase. The technology, engineering, and cost challenges to carry out any of these three options are monumental. It will require innovative ideas, game-changing technologies, and major collaborations at the international level to address the OD problem and preserve the near-Earth environment for future generations.
NASA Technical Reports Server (NTRS)
Schonfeld, D.; Charng, T.
1981-01-01
The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.
SEPAC: Spacelab Mission 1 report
NASA Technical Reports Server (NTRS)
1983-01-01
The SEPAC Spacelab Mission 1 activities relevant to software operations are reported. Spacelab events and problems that did not directly affect SEPAC but are of interest to experimenters are included. Spacelab Mission 1 was launched from KSC on 28 November 1983 at 10:10 Huntsville time. The Spacelab Mission met its objectives. There were two major problems associated with SEPAC: the loss of the EBA gun and the RAU 21.
Internal hysteresis experienced on a high pressure syn gas compressor
NASA Technical Reports Server (NTRS)
Zeidan, F. Y.
1984-01-01
A vibration instability phenomenon experienced in operating high pressure syn gas centrifugal compressors in two ammonia plants is described. The compressors were monitored by orbit and spectrum analysis for changes from baseline readings. It is found that internal hysteresis was the major destabilizing force; however, the problem was further complicated by seal lockup at the suction end of the compressor. A coupling lockup problem and a coupling fit problem, which frettage of the shaft, are also considered as contributors to the self excited vibrations.
Techniques for shuttle trajectory optimization
NASA Technical Reports Server (NTRS)
Edge, E. R.; Shieh, C. J.; Powers, W. F.
1973-01-01
The application of recently developed function-space Davidon-type techniques to the shuttle ascent trajectory optimization problem is discussed along with an investigation of the recently developed PRAXIS algorithm for parameter optimization. At the outset of this analysis, the major deficiency of the function-space algorithms was their potential storage problems. Since most previous analyses of the methods were with relatively low-dimension problems, no storage problems were encountered. However, in shuttle trajectory optimization, storage is a problem, and this problem was handled efficiently. Topics discussed include: the shuttle ascent model and the development of the particular optimization equations; the function-space algorithms; the operation of the algorithm and typical simulations; variable final-time problem considerations; and a modification of Powell's algorithm.
ERIC Educational Resources Information Center
HORNER, JAMES T.; PETERSON, EVERETT E.
A MAJOR PROBLEM OF AMERICAN YOUTH TODAY IS THAT OF QUALIFYING FOR AND HOLDING A JOB. GENERAL EDUCATION IS NOT ENOUGH FOR THE GREAT MAJORITY OF PEOPLE WHO MUST OPERATE FARMS, MACHINES, SHOPS, AND OFFICES AND PROVIDE SERVICES. YOUTH FACE INCREASED JOB COMPETITION BECAUSE OF THE INCREASED SIZE OF THE 14- TO 24-YEAR AGE GROUP. UNEMPLOYMENT AMONG YOUNG…
An adaptive array antenna for mobile satellite communications
NASA Technical Reports Server (NTRS)
Milne, Robert
1990-01-01
The design of an adaptive array antenna for land vehicle operation and its performance in an operational satellite system is described. Linear and circularly polarized antenna designs are presented. The acquisition and tracking operation of a satellite is described and the effect on the communications signal is discussed. A number of system requirements are examined that have a major impact on the antenna design. The results of environmental, power handling, and RFI testing are presented and potential problems are identified.
Research requirements to improve reliability of civil helicopters
NASA Technical Reports Server (NTRS)
Dougherty, J. J., III; Barrett, L. D.
1978-01-01
The major reliability problems of the civil helicopter fleet as reported by helicopter operational and maintenance personnel are documented. An assessment of each problem is made to determine if the reliability can be improved by application of present technology or whether additional research and development are required. The reliability impact is measured in three ways: (1) The relative frequency of each problem in the fleet. (2) The relative on-aircraft manhours to repair, associated with each fleet problem. (3) The relative cost of repair materials or replacement parts associated with each fleet problem. The data reviewed covered the period of 1971 through 1976 and covered only turbine engine aircraft.
Retention and application of Skylab experiment experiences to future programs
NASA Technical Reports Server (NTRS)
Milly, N.; Gillespie, V. G.
1974-01-01
Problems encountered on Skylab Experiments are listed in order that these experiences and associated recommendations might help to prevent similar problems on future programs. The criteria for selection of the data to be utilized was to identify the problem areas within the Skylab Program which would be of major significance with respect to future programs. Also, the problem had to be unique in that it would help identify to a designer/manufacturer an unforeseen or unanticipated occurrence which could cause failures, delays, or additional cost. Only those unexpected problems that may occur due to the nature of aerospace experiment environmental and operational requirements are included.
Quantifying incident-induced travel delays on freeways using traffic sensor data
DOT National Transportation Integrated Search
2008-02-01
Traffic congestion is a major operational problem for freeways in Washington State. Recent studies have estimated that more than 50% of freeway congestion is caused by traffic incidents. To help the Washington State Department of Transportation (WSDO...
Quantifying incident-induced travel delays on freeways using traffic sensor data
DOT National Transportation Integrated Search
2008-05-01
Traffic congestion is a major operational problem for freeways in Washington State. Recent studies have estimated that more than 50 percent of freeway congestion is caused by traffic incidents. To help the Washington State Department of Transportatio...
Possible impact of radar on pest management operations
NASA Technical Reports Server (NTRS)
Rainey, R. C.
1979-01-01
Radar in making and maintaining contact with the most important populations of major pests in different stages of flight is presented. The desert locust and the African armyworm are discussed in understanding problems and developing a more effective control of pests.
NASA Technical Reports Server (NTRS)
Bergeron, H. P.
1983-01-01
An analysis of incident data obtained from the NASA Aviation Safety Reporting System (ASRS) has been made to determine the problem areas in general aviation single-pilot IFR (SPIFR) operations. The Aviation Safety Reporting System data base is a compilation of voluntary reports of incidents from any person who has observed or been involved in an occurrence which was believed to have posed a threat to flight safety. This paper examines only those reported incidents specifically related to general aviation single-pilot IFR operations. The frequency of occurrence of factors related to the incidents was the criterion used to define significant problem areas and, hence, to suggest where research is needed. The data was cataloged into one of five major problem areas: (1) controller judgment and response problems, (2) pilot judgment and response problems, (3) air traffic control (ATC) intrafacility and interfacility conflicts, (4) ATC and pilot communication problems, and (5) IFR-VFR conflicts. In addition, several points common to all or most of the problems were observed and reported. These included human error, communications, procedures and rules, and work load.
A discussion on turbine design for safe operation
NASA Astrophysics Data System (ADS)
Brekke, H.
2012-11-01
The paper gives a brief description of the hydraulic design of Francis and Pelton runners. The dynamic behaviour at part load has been a major problem for low head and medium head Francis turbines. The main reason for this has been inter blade separation and unstable swirl flow in the draft tube. A description is given on the hydraulic design of X-BLADE runners to obtain stable operation on the whole range of operation by reducing the cross flow. A classical theoretical analysis is also given on the dynamic hydraulic load on Pelton buckets. Several CFD analyses of this non stationary flow have been presented during the last decade, but the velocity distribution in the jets have not been correct. Experimental research work is presented on the complexity of this problem.
Arteriovenous fistulas following lumbar laminectomy: the anatomy defined.
Quigley, T M; Stoney, R J
1985-11-01
Iatrogenic arteriovenous fistulas between the aorta or its major branches and the vena cava or its tributaries resulting from lumbar disc operations are uncommon but serious problems for the vascular surgeon. Using three cases from our experience and adding illustrations, x-ray films, and descriptive text we have precisely defined the anatomy of the major vessels at the L3-4, L4-5, and L5-S1 disc interspaces. This information will not only aid the surgeon in the repair of the chronic fistula but will help the surgeon who is called urgently to the operating room for bleeding and shock when preoperative angiography is not possible.
ERIC Educational Resources Information Center
Keister, Mary Elizabeth
This document is the final report of Phase One (1967-1970) of the Group Care of Infants Demonstration (Center) Project. This report devotes major attention to the problems of establishing, operating, and evaluating a group day care center for infant and toddler care. The Center project describes what is required to provide housing, equipment,…
Operational Problems Associated with Head-Up Displays during Instrument Flight.
1980-10-01
Force project engineers were Major Michael F. Rundle and Mr. William L. Welde . 41 4 TABLE OF CONTENTS Page ABBREVIATIONS...of Automotive Engineers SETP Society of Experimental Test Pilots SI Solid Instruments SNPL Syndicat National des Pilotes des Lignes (French ALPA) TACAN...Factors Relevent to Jet Upsets ," Lessons with Emphasis on Flight Mechanics from Operating Experience, Incidents, and Accidents, AGARD CP-76, 1971 153 J
DOT National Transportation Integrated Search
2017-08-01
Highway networks in the United States have been suffering from poor operational and structural condition states for the past decades. The consequent congestion problems often result in major delays, safety issues, and large amounts of additional fuel...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanfilippo, Antonio P.; Riensche, Roderick M.; Haack, Jereme N.
“Gamification”, the application of gameplay to real-world problems, enables the development of human computation systems that support decision-making through the integration of social and machine intelligence. One of gamification’s major benefits includes the creation of a problem solving environment where the influence of cognitive and cultural biases on human judgment can be curtailed through collaborative and competitive reasoning. By reducing biases on human judgment, gamification allows human computation systems to exploit human creativity relatively unhindered by human error. Operationally, gamification uses simulation to harvest human behavioral data that provide valuable insights for the solution of real-world problems.
IMPROVED CORROSION RESISTANCE OF ALUMINA REFRACTORIES
DOE Office of Scientific and Technical Information (OSTI.GOV)
John P. Hurley; Patty L. Kleven
2001-09-30
The initial objective of this project was to do a literature search to define the problems of refractory selection in the metals and glass industries. The problems fall into three categories: Economic--What do the major problems cost the industries financially? Operational--How do the major problems affect production efficiency and impact the environment? and Scientific--What are the chemical and physical mechanisms that cause the problems to occur? This report presents a summary of these problems. It was used to determine the areas in which the EERC can provide the most assistance through bench-scale and laboratory testing. The final objective of thismore » project was to design and build a bench-scale high-temperature controlled atmosphere dynamic corrosion application furnace (CADCAF). The furnace will be used to evaluate refractory test samples in the presence of flowing corrodents for extended periods, to temperatures of 1600 C under controlled atmospheres. Corrodents will include molten slag, steel, and glass. This test should prove useful for the glass and steel industries when faced with the decision of choosing the best refractory for flowing corrodent conditions.« less
[Hepatic surgery: 10 year experience at the Salvador Zubirán National Institute of Nutrition].
Orozco Zepeda, H; Mercado Díaz, M A; Takahashi Monroy, T; Prado Orozco, E; Chan Núñez, C
1992-01-01
Techniques for surgical liver resections have improved in the last years. The results obtained with liver resections in 67 patients with benign and malignant tumors in a referral hospital for liver diseases in Mexico are analyzed retrospectively, with the aim of knowing the results obtained with such problems in our country. For benign diseases we operated on 36 patients with mean age of 45 years (26 were women), we had one operative death. In 31 patients with operations for malignant tumors (16 were primary liver tumors), the mean age was 52 years and 17 were men; there were eight operative deaths. Major hepatic resections are justified, the results are very satisfactory in benign disease; a major proportion of complications have to be accepted in patients with malignant disease; however, the results are good if we realize that those patients will die in few months if the tumor is not removed.
Bakalar, Goran
2016-01-01
There are high functioning and low functioning ballast water treatment systems on board ships. In this study, five systems were analysed so as to methodically examine the operational difficulties for ship crew members while giving important consideration to sustainable environment practices. Multi-criteria analysis, a questionnaire, survey and interviews were used as the research method so as to ascertain and corroborate existing problems on board ships, and the reliability of the systems was calculated. The co-insistency, maintenance and the efficiency of the systems, were shown as being the major problem as there are no systems for tracking ship ballast operations from land. The treatment system that used oxidants was, through multi criteria analysis, evaluated as being the best and was ranked first. However, the survey results showed that the ship's crew had serious problems with this system which difficult to solve during the ship's operations with cargo. The deoxygenation system was the most appropriate according to ballast water treatment criteria in the port or at sea. The treatment system which used electrolysis with oxidant was better in terms of efficacy and the treatment system electrolysis with ultra violet light was better in terms of the criterion environment pollution footprint. During further research, it was shown that 7 % of the surveyed crew members had major problems with operating ballast water treatment systems, including the system which was ranked first through multi criteria analysis. They by-passed these systems while continuing to ballast or de-ballast. It was calculated that of the total time needed for the ballast water treatment system operation, 9 % of this time was used for repairs or maintenance of the systems. Some examples are changing a used UV bulb, cleaning the filter or controlling the amount of oxidant which would be discharged into the sea. A conclusion was made and solution was suggested. The study results emphasised taking action in the interest of protecting the natural world, with particular attention being given to environmental protection to support human life.
Application of ERTS-1 data to the protection and management of New Jersey's coastal environment
NASA Technical Reports Server (NTRS)
Yunghans, R. S. (Principal Investigator); Feinberg, E. B.; Stitt, J. A.; Mairs, R. L.; Wobber, F. J.; Macomber, R. T.; Stanczuk, D. T.; Thibult, D.
1974-01-01
The author has identified the following significant results. Quasi-operational information products for coastal zone management have been prepared using ERTS-1 imagery and collateral aerial photography. These products were applied to the practical regulation, protection, and management of New Jersey's coastal environment. Procedures were developed for the operational use of ERTS-1 data products within New Jersey's Department of Environmental Protection. Successful analysis and product preparation for operational needs centered on four major coastal resource problem areas: (1) detection of environmental changes in coastal areas, (2) siting of ocean outfalls, (3) monitoring of offshore waste disposal, and (4) calculation of recession rates along the Atlantic Shore. The utility and monetary benefits derived from ERTS and aircraft imagery for each problem area have been determined. The NJDEP estimates the possibility of $620,000 yearly savings through the use of an operational ERTS system and a one-time savings of $2.8 million on current or planned projects if a truly operational ERTS type satellite were available.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1984-01-01
Major accomplishments during the second quarter of 1984 were completion of the Diaphragm Separation Seal clear liquid testing, and initiation of Phase III Field Testing. Diaphragm operational testing was conducted on a clear water test loop. The test goals were to ensure; mechanical reliability of the Diaphragm Seal, safe operation with simulated component failure, and proper operation of the Diaphragm Buffer Volume Control System. This latter system is essential in controlling the phasing of the diaphragm with its driving plunger. These tests were completed successfully. All operational problems were solved. However, it must be emphasized that the Diaphragm Seal wouldmore » be damaged by allowing the pump to operate in a cavitating condition for an extended period of time. A change in the Field Test phase of the program was made regarding choice of field test site. There is no operating Syn-Fuel pilot plant capable of inexpensively producing the slurry stream required for the reciprocating pump testing. The Field Tests will now be conducted by first testing the prototype pump and separation seals in an ambient temperature sand water slurry. This will determine resistence to abrasive wear and determine any operation problems at pressure over a lengthy period of time. After successful conclusion of these tests the pump and seals will be operated with a high temperature oil, but without solids, to identify any problems associated with thermal gradients, thermal shock and differential growth. After successful completion of the high temperature clean oil tests the pump will be deemed ready for in-line installation at a designated Syn-Fuel pilot plant. The above approach avoids the expense and complications of a separate hot slurry test loop. It also reduces risk of operational problems while in-line at the pilot plant. 5 figs.« less
NASA Technical Reports Server (NTRS)
Dinsel, Alison; Jermstad, Wayne; Robertson, Brandan
2006-01-01
The Mechanical Design and Analysis Branch at the Johnson Space Center (JSC) is responsible for the technical oversight of over 30 mechanical systems flying on the Space Shuttle Orbiter and the International Space Station (ISS). The branch also has the responsibility for reviewing all mechanical systems on all Space Shuttle and International Space Station payloads, as part of the payload safety review process, through the Mechanical Systems Working Group (MSWG). These responsibilities give the branch unique insight into a large number of mechanical systems, and problems encountered during their design, testing, and operation. This paper contains narrative descriptions of lessons learned from some of the major problems worked on by the branch during the last two years. The problems are grouped into common categories and lessons learned are stated.
Operation Husky: Operational Art in Large Formation Combined Arms Maneuver
2013-12-10
mountain ranges; the character, position, and shape of frontiers; density of population and consequent refugee problem; transportation means; and the...About 10 percent of the population lived scattered throughout the countryside. The majority of the population was engaged in agriculture and had a...varied from 25 feet on the coast to 15 feet in the mountains . Provincial roads were not asphalted and they varied from 10 to 19 feet in width. Finally
Laminar Flow Control Leading Edge Systems in Simulated Airline Service
NASA Technical Reports Server (NTRS)
Wagner, R. D.; Maddalon, D. V.; Fisher, D. F.
1988-01-01
Achieving laminar flow on the wings of a commercial transport involves difficult problems associated with the wing leading edge. The NASA Leading Edge Flight Test Program has made major progress toward the solution of these problems. The effectiveness and practicality of candidate laminar flow leading edge systems were proven under representative airline service conditions. This was accomplished in a series of simulated airline service flights by modifying a JetStar aircraft with laminar flow leading edge systems and operating it out of three commercial airports in the United States. The aircraft was operated as an airliner would under actual air traffic conditions, in bad weather, and in insect infested environments.
COMPUTER TOOLS FOR SANITARY SEWER SYSTEM CAPACITY ANALYSIS AND PLANNING
Rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems has long been recognized as a major source of operating problems, causing poor performance of many sewer systems. RDII is the main cause of SSOs to customer basements, streets, or nearby streams and can a...
Towards a dynamical scheduler for ALMA: a science - software collaboration
NASA Astrophysics Data System (ADS)
Avarias, Jorge; Toledo, Ignacio; Espada, Daniel; Hibbard, John; Nyman, Lars-Ake; Hiriart, Rafael
2016-07-01
State-of-the art astronomical facilities are costly to build and operate, hence it is essential that these facilities must be operated as much efficiently as possible, trying to maximize the scientific output and at the same time minimizing overhead times. Over the latest decades the scheduling problem has drawn attention of research because new facilities have been demonstrated that is unfeasible to try to schedule observations manually, due the complexity to satisfy the astronomical and instrumental constraints and the number of scientific proposals to be reviewed and evaluated in near real-time. In addition, the dynamic nature of some constraints make this problem even more difficult. The Atacama Large Millimeter/submillimeter Array (ALMA) is a major collaboration effort between European (ESO), North American (NRAO) and East Asian countries (NAOJ), under operations on the Chilean Chajnantor plateau, at 5.000 meters of altitude. During normal operations at least two independent arrays are available, aiming to achieve different types of science. Since ALMA does not observe in the visible spectrum, observations are not limited to night time only, thus a 24/7 operation with little downtime as possible is expected when full operations state will have been reached. However, during preliminary operations (early-science) ALMA has been operated on tied schedules using around half of the whole day-time to conduct scientific observations. The purpose of this paper is to explain how the observation scheduling and its optimization is done within ALMA, giving details about the problem complexity, its similarities and differences with traditional scheduling problems found in the literature. The paper delves into the current recommendation system implementation and the difficulties found during the road to its deployment in production.
NASA Technical Reports Server (NTRS)
Hejduk, M. D.; Frigm, Ryan C.
2015-01-01
Satellite conjunction assessment is perhaps the fastest growing area in space situational awareness and protection with military, civil and commercial satellite owner-operators embracing more and more sophisticated processes to avoid the avoidable - namely collisions between high value space assets and orbital debris. NASA and Centre National d'Etudes Spatiales (CNES) have collaborated to offer an introductory short course on all the major aspects of the conjunctions assessment problem. This half-day course will cover satellite conjunction dynamics and theory. Joint Space Operations Center (JsPOC) conjunction data products, major risk assessment parameters and plots, conjunction remediation decision support, and present and future challenges. This briefing represents the NASA portion of the course.
NASA Technical Reports Server (NTRS)
Winter, J. R.
1984-01-01
For economic reasons, the steam drive for a large compressor was replaced by a large synchronous electric motor. Due to the resulting large increase in mass and because the unit was mounted on a steel frame approximately 18 feet above ground level, it was deemed necessary to determine if a steady state or transient vibration problem existed. There was a definite possibility that a resonant or near resonant condition could be encountered. The ensuing analysis, which led to some structural changes as the analysis proceeded, did not reveal any major steady state vibration problems. However, the analysis did indicate that the system would go through several natural frequencies of the support structure during start-up and shutdown. This led to the development of special start-up and shutdown procedures to minimize the possibility of exciting any of the major structural modes. A coast-down could result in significant support structure and/or equipment damage, especially under certain circumstances. In any event, dynamic field tests verified the major analytical results. The unit has now been operating for over three years without any major vibration problems.
Soil stabilization mat for lunar launch/landing site
NASA Technical Reports Server (NTRS)
Acord, Amy L.; Cohenour, Mark W.; Ephraim, Daniel; Gochoel, Dennis; Roberts, Jefferson G.
1990-01-01
Facilities which are capable of handling frequent arrivals and departures of spaceships between Earth and a lunar colony are necessary. The facility must be able to provide these services with minimal interruption of operational activity within the colony. The major concerns associated with the space traffic are the dust and rock particles that will be kicked up by the rocket exhaust. As a result of the reduced gravitation of the Moon, these particles scatter over large horizontal distances. This flying debris will not only seriously interrupt the routine operations of the colony, but could cause damage to the equipment and facilities surrounding the launch site. An approach to overcome this problem is presented. A proposed design for a lunar take-off/landing mat is presented. This proposal goes beyond dealing with the usual problems of heat and load resistances associated with take-off and landing, by solving the problem of soil stabilization at the site. Through adequate stabilization, the problem of flying debris is eliminated.
Research in Intelligent Automata (Phase I)
1964-04-29
results , major practical problems will not be overlooked, costs of real solutions may be assessed, and the operating models can also serve a major purpose...demonstration(s). In any case , the total cost of the equipments in these categories should be held to only a small fraction of the cost of all of the...number of factors , including ( I) Storage capaci ty required (2) Response time required (3) Current avai labi Ii ty and cost of associa ti ve
The AIBS In Yugoslavia: Programs in Biomedical Engineering
ERIC Educational Resources Information Center
Thompson, Mary-Frances
1978-01-01
Programs in biomedical engineering have been developing worldwide since World War II. This article describes a multidisciplinary program which operates in Yugoslavia through a cooperative effort between that county and the AIBS. A major problem has been the slowness with which hospitals accept the concept of biomedical engineering. (MA)
Mercedes-Benz pyloroplasty: a new technique.
Vashney, S; Somers, S S
2001-01-01
Closure of large duodeno-pyloro-gastrotomy can be difficult. The resulting 'pyloroplasty' may lead to major deformity at the gastric outlet. We describe a technique that combines features of the Heineke-Mikulicz pyloroplasty and V-Y plasty. The technique is simple and is not associated with any new post-operative problem.
Solar Heating and Cooling for a Controls Manufacturing Plant Lumberton, New Jersey
NASA Technical Reports Server (NTRS)
1982-01-01
Comprehensive report documents computer-controlled system which has separate solar-collector and cooling-tower areas located away from building and is completely computer controlled. System description, test data, major problems and resolution, performance, operation and maintenance, manufacturer's literature and drawing comprise part of 257-page report.
Use of Thermography to Screen for Sub-Clinical Bumblefoot in Poultry
USDA-ARS?s Scientific Manuscript database
Bumblefoot is a chronic inflammation of the plantar metatarsal and or digital pads of the foot (pododermatitis). It is one of the major health problems of birds including chickens and is responsible for significant economic losses in commercial poultry operations. Bumblefoot is affected by both endo...
Solar heating system installed at Telex Communications, Inc., Blue Earth, Minnesota
NASA Technical Reports Server (NTRS)
1977-01-01
The solar heating system for space heating a 97,000 square foot building which houses administrative offices, assembly areas, and warehouse space is summarized. Information on system description, test data, major problems and resolutions, performance, operation and maintenance manual, manufacturer's literature, and as-built drawings is presented.
OPERATION IVY. Report of Commander, Task Group 132.1. Pacific Proving Grounds. Joint Task Force 132
1984-10-31
3.4.1 Device Planning One of the major purposes of Operation Greenhouse was to answer key questions relating to the possibility of developing...thermonuclear explosions. The Greenhouse George and Item Shots were Important steps in the investigation of basic problems in the development of a...January 1952, staff studies were made which were based on Greenhouse experience and on the best available estimates of the requirements pe- culiar to
Evolving policies to regulate pollution from animal feeding operations.
Centner, T J
2001-11-01
Due to concentrations of animals at large facilities, animal feeding operations (AFOs) have emerged as a major potential source of water pollution. The federal government regulates concentrated animal feeding operations under its point-source pollution permitting regulations. A major determinant of whether an operation must apply for a permit is the number of animals at an individual lot or facility. This paper examines federal mandatory controls and voluntary guidelines that seek to reduce contaminant pollution from AFOs. Land treatment practices are delineated due to their importance in reducing the injurious by-products of agricultural production. An evaluation of proposed revisions to federal regulations on confined animal feeding operations suggests they diverge from their goal of controlling water pollution. Federal regulations focus on the size of operation and amount of manure governed by the permitting process to the exclusion of other criteria related to the impairment of water quality. Given the uncertainties about the amount of pollution from AFOs, lack of enforcement of existing regulations, localization of problems, and possible alternatives for addressing the pollution, more demanding federal regulations may not form an appropriate response.
Making sense of quantum operators, eigenstates and quantum measurements
NASA Astrophysics Data System (ADS)
Gire, Elizabeth; Manogue, Corinne
2012-02-01
Operators play a central role in the formalism of quantum mechanics. In particular, operators corresponding to observables encode important information about the results of quantum measurements. We interviewed upper-level undergraduate physics majors about their understanding of the role of operators in quantum measurements. Previous studies have shown that many students think of measurements on quantum systems as being deterministic and that measurements mathematically correspond to operators acting on the initial quantum state. This study is consistent with and expands on those results. We report on how two students make sense of a quantum measurement problem involving sequential measurements and the role that the eigenvalue equation plays in this sense-making.
Payload Instrument Design Rules for Safe and Efficient Flight Operations
NASA Astrophysics Data System (ADS)
Montagnon, E.; Ferri, P.
2004-04-01
Payload operations are often being neglected in favour of optimisation of scientific performance of the instrument design. This has major drawbacks in terms of cost, safety, efficiency of operations and finally science return. By taking operational aspects into account in the early phases of the instrument design, with a minimum more cultural than financial or technological additional effort, many problems can be avoided or minimized, with significant benefits to be gained in the mission execution phases. This paper presents possible improvements based on the use of the telemetry and telecommand packet standard, proper sharing of autonomy functions between instrument and platform, and enhanced interface documents.
Adding control to arbitrary unknown quantum operations
Zhou, Xiao-Qi; Ralph, Timothy C.; Kalasuwan, Pruet; Zhang, Mian; Peruzzo, Alberto; Lanyon, Benjamin P.; O'Brien, Jeremy L.
2011-01-01
Although quantum computers promise significant advantages, the complexity of quantum algorithms remains a major technological obstacle. We have developed and demonstrated an architecture-independent technique that simplifies adding control qubits to arbitrary quantum operations—a requirement in many quantum algorithms, simulations and metrology. The technique, which is independent of how the operation is done, does not require knowledge of what the operation is, and largely separates the problems of how to implement a quantum operation in the laboratory and how to add a control. Here, we demonstrate an entanglement-based version in a photonic system, realizing a range of different two-qubit gates with high fidelity. PMID:21811242
Types of motivating operations in interventions with problem behavior: a systematic review.
Simó-Pinatella, David; Font-Roura, Josep; Planella-Morató, Joaquima; McGill, Peter; Alomar-Kurz, Elisabeth; Giné, Climent
2013-01-01
A motivating operation (MO) alters both the effectiveness of a stimulus as a reinforcer and the current frequency of all behavior that has been reinforced by that particular stimulus. This article reviews studies that have manipulated a MO during interventions with school-age participants with intellectual disabilities and problem behavior. A systematic review was conducted using the following major electronic databases: PsychInfo, Education Resources Information Center, Science Direct, Blackwell, SAGE, and Medline. A total of 31 published articles representing 55 participants was examined. Findings from this study suggest that the modification of a MO usually has an effect on the problem behavior by either establishing or abolishing its motivation. Furthermore, a relationship was found between the type of MO and the behavioral function identified. The theoretical and practical implications of these findings, limitations of this study and potential issues for future research are discussed.
NASA Technical Reports Server (NTRS)
Bergeron, H. P.
1980-01-01
Data obtained from the NASA Aviation Safety Reporting System (ASRS) data base were used to determine problems in general aviation single pilot IFR operations. The data examined consisted of incident reports involving flight safety in the National Aviation System. Only those incidents involving general aviation fixed wing aircraft flying under IFR in instrument meteorological conditions were analyzed. The data were cataloged into one of five major problem areas: (1) controller judgement and response problems; (2) pilot judgement and response problems; (3) air traffic control intrafacility and interfacility conflicts; (4) ATC and pilot communications problems; and (5) IFR-VFR conflicts. The significance of the related problems, and the various underlying elements associated with each are discussed. Previous ASRS reports covering several areas of analysis are reviewed.
Potential interoperability problems facing multi-site radiation oncology centers in The Netherlands
NASA Astrophysics Data System (ADS)
Scheurleer, J.; Koken, Ph; Wessel, R.
2014-03-01
Aim: To identify potential interoperability problems facing multi-site Radiation Oncology (RO) departments in the Netherlands and solutions for unambiguous multi-system workflows. Specific challenges confronting the RO department of VUmc (RO-VUmc), which is soon to open a satellite department, were characterized. Methods: A nationwide questionnaire survey was conducted to identify possible interoperability problems and solutions. Further detailed information was obtained by in-depth interviews at 3 Dutch RO institutes that already operate in more than one site. Results: The survey had a 100% response rate (n=21). Altogether 95 interoperability problems were described. Most reported problems were on a strategic and semantic level. The majority were DICOM(-RT) and HL7 related (n=65), primarily between treatment planning and verification systems or between departmental and hospital systems. Seven were identified as being relevant for RO-VUmc. Departments have overcome interoperability problems with their own, or with tailor-made vendor solutions. There was little knowledge about or utilization of solutions developed by Integrating the Healthcare Enterprise Radiation Oncology (IHE-RO). Conclusions: Although interoperability problems are still common, solutions have been identified. Awareness of IHE-RO needs to be raised. No major new interoperability problems are predicted as RO-VUmc develops into a multi-site department.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collins, Benjamin S.; Hamilton, Steven P.; Jarrett, Michael G.
This report describes the performance improvements made to the VERA Core Simulator (VERA-CS) during FY2016. The development of the VERA Core Simulator has focused on the capability needed to deplete physical reactors and help solve various problems; this capability required the accurate simulation of many operating cycles of a nuclear power plant. The first section of this report introduces two test problems used to assess the run-time performance of VERA-CS using a source dated February 2016. The next section provides a brief overview of the major modifications made to decrease the computational cost. Following the descriptions of the major improvements,more » the run-time for each improvement is shown. Conclusions on the work are presented, and further follow-on performance improvements are suggested.« less
A practical guide to the Piccolo autopilot
NASA Astrophysics Data System (ADS)
Mornhinweg, Anton
In support of a UAV contract the Piccolo SL and Piccolo II autopilots were installed and operated on various aircraft. Numerous problems with the autopilot setup and analysis processes were found along with numerous problems with documentation and autopilot system information. Major areas of concern are identified along with objectives to eliminate the major areas of concern. Piccolo simulator vehicle gain calculations and Piccolo generation 2 version 2.1.4 control laws are reverse engineered. A complete modeling guide is created. Methods are developed to perform and analyze doublet maneuvers. A series of flight procedures are outlined that include methods for tuning gains. A series of MATLAB graphical user interfaces were created to analyze flight data and pertinent control loop data for gain tuning.
Problem posing vs problem solving.
Happs, S J
1991-04-01
This paper addresses the notion of adult education and places it within the context of the literature on adult development. Emphasis is placed on the work of Klaus Riegel (1973) who suggested a different interpretation of adult development. Dialectic operations is perceived to be the final stage of cognitive development, as opposed to formal operational thought, the traditional interpretation. Dialectic operations is a way of thinking which seeks to discover a whole new series of questions to be asked, rather than in finding 'once and for all' answers. The concepts put forward by Riegel are used as the foundation for a different interpretation of andragogy, based on the work of the Nottingham Andragogy Group (1983). The educational approach suggested to a large extent is diametrically opposed to the much criticised 'traditional' training of nurses. The view is expressed that although this is a different approach it is nonetheless worthwhile and should be embraced, particularly when nurse education is undergoing such major change.
Government/Industry Workshop on Payload Loads Technology
NASA Technical Reports Server (NTRS)
1978-01-01
A fully operational space shuttle is discussed which will offer science the opportunity to explore near earth orbit and finally interplanetary space on nearly a limitless basis. This multiplicity of payload/experiment combinations and frequency of launches places many burdens on dynamicists to predict launch and landing environments accurately and efficiently. Two major problems are apparent in the attempt to design for the diverse environments: (1) balancing the design criteria (loads, etc.) between launch and orbit operations, and (2) developing analytical techniques that are reliable, accurate, efficient, and low cost to meet the challenge of multiple launches and payloads. This paper deals with the key issues inherent in these problems, the key trades required, the basic approaches needed, and a summary of the state-of-the-art techniques.
Major oil spill response coordination in the combat of spills in Bahrain waters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, D.J.S.; James, J.D.
1985-01-01
On Aug. 25, 1980, without warning, a large oil slick invaded the north and west coasts of Bahrain. This serious incident was designated a national emergency, and a special high-level government committee was established immediately to handle the response procedure. This paper describes how the committee functioned with the private sector and the problems encountered and overcome. The lessons learned have stimulated interest in the proposed use of computers to aid combat operations as both a technical tool and an information service. In addition, this experience can guide those responsible for controlling response operations for future major oil spills inmore » coastal areas. With proper planning, a highly satisfactory cooperative organization can be established between goverment and the private sector to respond effectively, economically, and with minimum environmental damage to a major oil spill affecting coastal waters and shorelines. Part of this planning is to collate and record the major available response equipment and material packages, thereby increasing the necessary state of readiness.« less
High-level neutron coincidence counter maintenance manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swansen, J.; Collinsworth, P.
1983-05-01
High-level neutron coincidence counter operational (field) calibration and usage is well known. This manual makes explicit basic (shop) check-out, calibration, and testing of new units and is a guide for repair of failed in-service units. Operational criteria for the major electronic functions are detailed, as are adjustments and calibration procedures, and recurrent mechanical/electromechanical problems are addressed. Some system tests are included for quality assurance. Data on nonstandard large-scale integrated (circuit) components and a schematic set are also included.
Control system design for the large space systems technology reference platform
NASA Technical Reports Server (NTRS)
Edmunds, R. S.
1982-01-01
Structural models and classical frequency domain control system designs were developed for the large space systems technology (LSST) reference platform which consists of a central bus structure, solar panels, and platform arms on which a variety of experiments may be mounted. It is shown that operation of multiple independently articulated payloads on a single platform presents major problems when subarc second pointing stability is required. Experiment compatibility will be an important operational consideration for systems of this type.
Surveillance systems for intermodal transportation
NASA Astrophysics Data System (ADS)
Jakovlev, Sergej; Voznak, Miroslav; Andziulis, Arunas
2015-05-01
Intermodal container monitoring is considered a major security issue in many major logistic companies and countries worldwide. Current representation of the problem, we face today, originated in 2002, right after the 9/11 attacks. Then, a new worldwide Container Security Initiative (CSI, 2002) was considered that shaped the perception of the transportation operations. Now more than 80 larger ports all over the world contribute to its further development and integration into everyday transportation operations and improve the regulations for the developing regions. Although, these new improvements allow us to feel safer and secure, constant management of transportation operations has become a very difficult problem for conventional data analysis methods and information systems. The paper deals with a proposal of a whole new concept for the improvement of the Containers Security Initiative (CSI) by virtually connecting safety, security processes and systems. A conceptual middleware approach with deployable intelligent agent modules is proposed to be used with possible scenarios and a testbed is used to test the solution. Middleware examples are visually programmed using National Instruments LabView software packages and Wireless sensor network hardware modules. An experimental software is used to evaluate he solution. This research is a contribution to the intermodal transportation and is intended to be used as a means or the development of intelligent transport systems.
An Assessment of Six School-Based Clinics: Services, Impact and Potential.
ERIC Educational Resources Information Center
Kirby, Douglas; And Others
For two decades, school-based clinics have been providing basic health care to medically underserved teenagers and addressing the increasingly complex health and social problems facing young people, particularly unintended pregnancy. Today there are 150 school-based clinics operating in most major cities and many rural areas. In 1984, the Center…
USDA-ARS?s Scientific Manuscript database
Phlebotomine sand flies are small hematophagous flies present throughout tropical and subtropical areas of the world and are vectors of human and zoonotic leishmaniases. Human cutaneous leishmaniasis is a debilitating disease presenting major problems for U.S. military operations in the Middle East,...
Narcotics-Fueled Violence in Mexico: Crisis for the United States?
2011-03-24
cartels in Mexico which operate on a highly geographic basis. The DTOs responsible for the majority of violence in Mexico are the Tijuana, Gulf, Sinaloa ...infrastructure along the border region to deal with problems such as a mass migration . The Army maintains large facilities at Fort Bliss in El Paso, Texas and
DSS 13 microprocessor antenna controller
NASA Technical Reports Server (NTRS)
Gosline, R. M.
1988-01-01
A microprocessor-based antenna monitor and control system with multiple CPUs are described. The system was developed as part of the unattended station project for DSS 13 and was enhanced for use by the SETI project. The operational features, hardware, and software designs are described, and a discussion is provided of the major problems encountered.
Contingency Contracting and Operant Behavior Change: An Exercise in Applied Behavior Analysis.
ERIC Educational Resources Information Center
Mann, Ronald A.
Until recently, the use of contingency contracting has been largely an issue of theory and discussion with little experimental research evidence gathered to support efficacy. Two major reasons for this problem are suggested and discussed: (1) the concept of contingency contracting has not been adequately defined nor its minimal requirements…
Tibial plafond fractures: limited incision reduction with percutaneous fixation.
Salton, Heather L; Rush, Shannon; Schuberth, John
2007-01-01
This study was a retrospective review of 18 patients with 19 pilon fractures treated with limited incision reduction and percutaneous plate fixation of the tibia. Patients were treated with either a 1- or 2-stage protocol. The latter consisted of placement of an external fixator followed by definitive reduction. The emphasis of analysis was placed on the identification of complications to the soft tissue envelope or bone-healing problems within the first 6 months after surgery. A major complication was defined as an unplanned operation within the first 6 months. Minor complications were any superficial wound defects that did not require operative intervention to resolve or any malunion or delayed union. With this protocol, no major complications were encountered. Minor complications were identified in 4 patients (4 fractures) of which 2 were minor wound problems. One patient developed a malunion, and the other had a delayed union. Four patients requested removal of prominent hardware. These results indicate that limited incision reduction and percutaneous plate fixation lead to safe methods of stabilization. The authors also provide guidance and strategies for the consistent execution of this technique.
Development of common neural representations for distinct numerical problems
Chang, Ting-Ting; Rosenberg-Lee, Miriam; Metcalfe, Arron W. S.; Chen, Tianwen; Menon, Vinod
2015-01-01
How the brain develops representations for abstract cognitive problems is a major unaddressed question in neuroscience. Here we tackle this fundamental question using arithmetic problem solving, a cognitive domain important for the development of mathematical reasoning. We first examined whether adults demonstrate common neural representations for addition and subtraction problems, two complementary arithmetic operations that manipulate the same quantities. We then examined how the common neural representations for the two problem types change with development. Whole-brain multivoxel representational similarity (MRS) analysis was conducted to examine common coding of addition and subtraction problems in children and adults. We found that adults exhibited significant levels of MRS between the two problem types, not only in the intra-parietal sulcus (IPS) region of the posterior parietal cortex (PPC), but also in ventral temporal-occipital, anterior temporal and dorsolateral prefrontal cortices. Relative to adults, children showed significantly reduced levels of MRS in these same regions. In contrast, no brain areas showed significantly greater MRS between problem types in children. Our findings provide novel evidence that the emergence of arithmetic problem solving skills from childhood to adulthood is characterized by maturation of common neural representations between distinct numerical operations, and involve distributed brain regions important for representing and manipulating numerical quantity. More broadly, our findings demonstrate that representational analysis provides a powerful approach for uncovering fundamental mechanisms by which children develop proficiencies that are a hallmark of human cognition. PMID:26160287
NASA flight cell and battery issues
NASA Technical Reports Server (NTRS)
Schulze, N. R.
1989-01-01
The author presents the important battery and cell problems, encompassing both test failures and accidents, which were encountered during the past year. Practical issues facing programs, which have to be considered in the development of a battery program strategy, are addressed. The problems of one program, the GRO (Gamma Ray Observatory), during the past year are focused on to illustrate the fundamental types of battery problems that occur. Problems encountered by other programs are briefly mentioned to complete the accounting. Two major categories of issues are defined, namely, whose which are quality and design related, i.e., problems having inherent manufacturing-process-related aspects with an impact on cell reliability, and these which are accident triggered or man induced, i.e., those operational issues having an impact on battery and cell reliability.
Modifications to the rapid melt/rapid quench and transparent polymer video furnaces for the KC-135
NASA Technical Reports Server (NTRS)
Smith, Guy A.; Kosten, Sue E.; Workman, Gary L.
1990-01-01
Given here is a summary of tasks performed on two furnace systems, the Transparent Polymer (TPF) and the Rapid Melt/Rapid Quench (RMRQ) furnaces, to be used aboard NASA's KC-135. It was determined that major changes were needed for both furnaces to operate according to the scientific investigators' experiment parameters. Discussed here are what the problems were, what was required to solve the problems, and possible future enhancements. It was determined that the enhancements would be required for the furnaces to perform at their optimal levels. Services provided include hardware and software modifications, Safety DataPackage documentation, ground based testing, transportation to and from Ellington Air Field, operation of hardware during KC-135 flights, and post-flight data processing.
Compatibility of pressure sensitive adhesives with recycling unit operations
David Bormett; Carl Houtman; Said Abubakr; Joseph Peng
1999-01-01
Removal of pressure sensitive adhesives (PSAs) from recovered paper is a major problem facing the paper recycling industry. As a result of a United States Postal Service (USPS) initiative, which currently purchases about 12% of domestic PSA production, a team was formed consisting of representatives from the USPS, the Forest Products Laboratory, Springborn Testing and...
Understanding Beginning Teacher Induction: A Contextualized Examination of Best Practice
ERIC Educational Resources Information Center
Kearney, Sean
2014-01-01
The problems that teachers face early in their careers are a major factor in growing rates of attrition among neophyte teachers. According to the Organisation for Economic Co-operation and Development, high rates of attrition, coupled with and aging teacher population in many countries in the developed world, may cause a teacher shortage crisis in…
49 CFR 520.5 - Guidelines for identifying major actions significantly affecting the environment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... indirectly result in a significant increase in the problem of solid waste, as in the disposal of motor... directly or indirectly result in a significant increase in noise levels, either within a motor vehicle's... significant increase in the energy or fuel necessary to operate a motor vehicle, including but not limited to...
49 CFR 520.5 - Guidelines for identifying major actions significantly affecting the environment.
Code of Federal Regulations, 2014 CFR
2014-10-01
... indirectly result in a significant increase in the problem of solid waste, as in the disposal of motor... directly or indirectly result in a significant increase in noise levels, either within a motor vehicle's... significant increase in the energy or fuel necessary to operate a motor vehicle, including but not limited to...
49 CFR 520.5 - Guidelines for identifying major actions significantly affecting the environment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... indirectly result in a significant increase in the problem of solid waste, as in the disposal of motor... directly or indirectly result in a significant increase in noise levels, either within a motor vehicle's... significant increase in the energy or fuel necessary to operate a motor vehicle, including but not limited to...
Prevalence of DSM-IV major depression among U.S. military personnel: Meta-analysis and simulation
Gadermann, Anne M.; Engel, COL Charles C.; Naifeh, James A.; Nock, Matthew K.; Petukhova, Maria; Santiago, LCDR Patcho N.; Benjamin, Wu; Zaslavsky, Alan M.; Kessler, Ronald C.
2014-01-01
A meta-analysis of 25 epidemiological studies estimated the prevalence of recent DSM-IV major depression among U.S. military personnel. Best estimates of recent prevalence (standard error) were 12.0 percent (1.2) among currently deployed, 13.1 percent (1.8) among previously deployed and 5.7 percent (1.2) among never deployed. Consistent correlates of prevalence were being female, enlisted, young (ages 17 to 25), unmarried and having less than a college education. Simulation of data from a national general population survey was used to estimate expected lifetime prevalence of major depression among respondents with the socio-demographic profile and none of the enlistment exclusions of Army personnel. In this simulated sample, 16.2 percent (3.1) of respondents had lifetime major depression and 69.7 percent (8.5) of first onsets occurred before expected age of enlistment. Numerous methodological problems limit the results of the meta-analysis and simulation. The paper closes with a discussion of recommendations for correcting these problems in future surveillance and operational stress studies. PMID:22953441
Prediction of anthropometric accommodation in aircraft cockpits
NASA Astrophysics Data System (ADS)
Zehner, Gregory Franklin
Designing aircraft cockpits to accommodate the wide range of body sizes existing in the U.S. population has always been a difficult problem for Crewstation Engineers. The approach taken in the design of military aircraft has been to restrict the range of body sizes allowed into flight training, and then to develop standards and specifications to ensure that the majority of the pilots are accommodated. Accommodation in this instance is defined as the ability to: (1) Adequately see, reach, and actuate controls; (2) Have external visual fields so that the pilot can see to land, clear for other aircraft, and perform a wide variety of missions (ground support/attack or air to air combat); and (3) Finally, if problems arise, the pilot has to be able to escape safely. Each of these areas is directly affected by the body size of the pilot. Unfortunately, accommodation problems persist and may get worse. Currently the USAF is considering relaxing body size entrance requirements so that smaller and larger people could become pilots. This will make existing accommodation problems much worse. This dissertation describes a methodology for correcting this problem and demonstrates the method by predicting pilot fit and performance in the USAF T-38A aircraft based on anthropometric data. The methods described can be applied to a variety of design applications where fitting the human operator into a system is a major concern. A systematic approach is described which includes: defining the user population, setting functional requirements that operators must be able to perform, testing the ability of the user population to perform the functional requirements, and developing predictive equations for selecting future users of the system. Also described is a process for the development of new anthropometric design criteria and cockpit design methods that assure body size accommodation is improved in the future.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berlin, G.
Humidity plays a major role in health, comfort, and production. This article is a brief overview of the technologies available and a detailed explanation of how to calculate humidification loads. The problems caused by dry air vary from one building to another and from one area to another. But basically, there are three major problem types: static electricity, poor moisture stability, health and comfort problems. In today's business offices, static electricity can disrupt operations and increase operating costs. In printing facilities, low humidity causes poor ink registration. Also, sheets of paper stick together and jam machines, wasting time and paper.more » In computer rooms and data processing areas, dry air leads to static electric discharges that cause circuit board failure, dust buildup on heads, and storage tape breakage. Moisture stability impacts industrial processes and the materials they use. In many cases, product and material deterioration is directly related to moisture fluctuations and lack of humidity control. Books, antiques, paper, wood and wood products, and fruits and vegetables are a few items that can be ruined by low or changing humidity. The health impact of low humidity shows up in dry nasal and thread membranes, dry and itchy skin, and irritated eyes. For employees, this means greater susceptibility to colds and other viral infections. The results is higher absenteeism when humidity is low, which translates into lost productivity and profits.« less
NASA Technical Reports Server (NTRS)
Smith, Phillip J.; Billings, Charles; McCoy, C. Elaine; Orasanu, Judith
1999-01-01
The air traffic management system in the United States is an example of a distributed problem solving system. It has elements of both cooperative and competitive problem-solving. This system includes complex organizations such as Airline Operations Centers (AOCs), the FAA Air Traffic Control Systems Command Center (ATCSCC), and traffic management units (TMUs) at enroute centers and TRACONs, all of which have a major focus on strategic decision-making. It also includes individuals concerned more with tactical decisions (such as air traffic controllers and pilots). The architecture for this system has evolved over time to rely heavily on the distribution of tasks and control authority in order to keep cognitive complexity manageable for any one individual operator, and to provide redundancy (both human and technological) to serve as a safety net to catch the slips or mistakes that any one person or entity might make. Currently, major changes are being considered for this architecture, especially with respect to the locus of control, in an effort to improve efficiency and safety. This paper uses a series of case studies to help evaluate some of these changes from the perspective of system complexity, and to point out possible alternative approaches that might be taken to improve system performance. The paper illustrates the need to maintain a clear understanding of what is required to assure a high level of performance when alternative system architectures and decompositions are developed.
Wind-assist irrigation and electrical-power generation
NASA Astrophysics Data System (ADS)
Nelson, V.; Starcher, K.
1982-07-01
A wind turbine is mechanically connected to an existing irrigation well. The system can be operated in three modes: electric motor driving the water turbine pump. Wind assist mode where wind turbine supplements power from the utility line to drive the water turbine pump. At wind speeds of 12 m/s and greater, the wind turbine can pump water (15 kW) and feed power (10 kW) back into the utility grid at the same time. Electrical generation mode where the water pump is disconnected and all power is fed back to the utility grid. The concept is technically viable as the mechanical connection allows for a smooth transfer of power in parallel with an existing power source. Minor problems caused delays and major problems of two rotor failures precluded enough operation time to obtain a good estimation of the economics. Because reliability and maintenance are difficult problems with prototype or limited production wind energy conversion systems, the expense of the demonstration project has exceeded the estimated cost by a large amount.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dall-Anese, Emiliano; Zhou, Xinyang; Liu, Zhiyuan
This paper considers distribution networks with distributed energy resources and discrete-rate loads, and designs an incentive-based algorithm that allows the network operator and the customers to pursue given operational and economic objectives, while concurrently ensuring that voltages are within prescribed limits. Four major challenges include: (1) the non-convexity from discrete decision variables, (2) the non-convexity due to a Stackelberg game structure, (3) unavailable private information from customers, and (4) different update frequency from two types of devices. In this paper, we first make convex relaxation for discrete variables, then reformulate the non-convex structure into a convex optimization problem together withmore » pricing/reward signal design, and propose a distributed stochastic dual algorithm for solving the reformulated problem while restoring feasible power rates for discrete devices. By doing so, we are able to statistically achieve the solution of the reformulated problem without exposure of any private information from customers. Stability of the proposed schemes is analytically established and numerically corroborated.« less
Outcomes following major emergency gastric surgery: the importance of specialist surgeons.
Khan, O A; McGlone, E R; Mercer, S J; Somers, S S; Toh, S K C
2015-01-01
The increasing subspecialisation of general surgeons in their elective work may result in problems for the provision of expert care for emergency cases. There is very little evidence of the impact of subspecialism on outcomes following emergency major upper gastrointestinal surgery. This prospective study investigated whether elective subspecialism of general surgeon is associated with a difference in outcome following major emergency gastric surgery. Between February 1994 and June 2010, the data from all emergency major gastric procedures (defined as patients who underwent laparotomy within 12 hours of referral to the surgical service for bleeding gastroduodenal ulcer and/or undergoing major gastric resection) was prospectively recorded. The sub-specialty interest of operating surgeon was noted and related to post-operative outcomes. Over the study period, a total of 63 major gastric procedures were performed of which 23 (37%) were performed by specialist upper gastrointestinal (UGI) consultants. Surgery performed by a specialist UGI surgeon was associated with a significantly lower surgical complication (4% vs. 28% of cases; p=0.04) and in-patient mortality rate (22% vs. 50%; p=0.03). Major emergency gastric surgery has significantly better clinical outcomes when performed by a specialist UGI surgeon. These results have important implications for provision of an emergency general surgical service. Copyright© Acta Chirurgica Belgica.
Solar heating and cooling system installed at RKL Controls Company, Lumberton, New Jersey
NASA Technical Reports Server (NTRS)
1981-01-01
The final results of the design and operation of a computer controlled solar heated and cooled 40,000 square foot manufacturing building, sales office, and computer control center/display room are summarized. The system description, test data, major problems and resolutions, performance, operation and maintenance manual, equipment manufacturers' literature, and as-built drawings are presented. The solar system is composed of 6,000 square feet of flat plate collectors, external above ground storage subsystem, controls, absorption chiller, heat recovery, and a cooling tower.
Imaging evaluation of non-alcoholic fatty liver disease: focused on quantification.
Lee, Dong Ho
2017-12-01
Non-alcoholic fatty liver disease (NAFLD) has been an emerging major health problem, and the most common cause of chronic liver disease in Western countries. Traditionally, liver biopsy has been gold standard method for quantification of hepatic steatosis. However, its invasive nature with potential complication as well as measurement variability are major problem. Thus, various imaging studies have been used for evaluation of hepatic steatosis. Ultrasonography provides fairly good accuracy to detect moderate-to-severe degree hepatic steatosis, but limited accuracy for mild steatosis. Operator-dependency and subjective/qualitative nature of examination are another major drawbacks of ultrasonography. Computed tomography can be considered as an unsuitable imaging modality for evaluation of NAFLD due to potential risk of radiation exposure and limited accuracy in detecting mild steatosis. Both magnetic resonance spectroscopy and magnetic resonance imaging using chemical shift technique provide highly accurate and reproducible diagnostic performance for evaluating NAFLD, and therefore, have been used in many clinical trials as a non-invasive reference of standard method.
Imaging evaluation of non-alcoholic fatty liver disease: focused on quantification
2017-01-01
Non-alcoholic fatty liver disease (NAFLD) has been an emerging major health problem, and the most common cause of chronic liver disease in Western countries. Traditionally, liver biopsy has been gold standard method for quantification of hepatic steatosis. However, its invasive nature with potential complication as well as measurement variability are major problem. Thus, various imaging studies have been used for evaluation of hepatic steatosis. Ultrasonography provides fairly good accuracy to detect moderate-to-severe degree hepatic steatosis, but limited accuracy for mild steatosis. Operator-dependency and subjective/qualitative nature of examination are another major drawbacks of ultrasonography. Computed tomography can be considered as an unsuitable imaging modality for evaluation of NAFLD due to potential risk of radiation exposure and limited accuracy in detecting mild steatosis. Both magnetic resonance spectroscopy and magnetic resonance imaging using chemical shift technique provide highly accurate and reproducible diagnostic performance for evaluating NAFLD, and therefore, have been used in many clinical trials as a non-invasive reference of standard method. PMID:28994271
Using Multimodal Input for Autonomous Decision Making for Unmanned Systems
NASA Technical Reports Server (NTRS)
Neilan, James H.; Cross, Charles; Rothhaar, Paul; Tran, Loc; Motter, Mark; Qualls, Garry; Trujillo, Anna; Allen, B. Danette
2016-01-01
Autonomous decision making in the presence of uncertainly is a deeply studied problem space particularly in the area of autonomous systems operations for land, air, sea, and space vehicles. Various techniques ranging from single algorithm solutions to complex ensemble classifier systems have been utilized in a research context in solving mission critical flight decisions. Realized systems on actual autonomous hardware, however, is a difficult systems integration problem, constituting a majority of applied robotics development timelines. The ability to reliably and repeatedly classify objects during a vehicles mission execution is vital for the vehicle to mitigate both static and dynamic environmental concerns such that the mission may be completed successfully and have the vehicle operate and return safely. In this paper, the Autonomy Incubator proposes and discusses an ensemble learning and recognition system planned for our autonomous framework, AEON, in selected domains, which fuse decision criteria, using prior experience on both the individual classifier layer and the ensemble layer to mitigate environmental uncertainty during operation.
Using game technologies to improve the safety of construction plant operations.
Guo, Hongling; Li, Heng; Chan, Greg; Skitmore, Martin
2012-09-01
Many accidents occur world-wide in the use of construction plant and equipment, and safety training is considered by many to be one of the best approaches to their prevention. However, current safety training methods/tools are unable to provide trainees with the hands-on practice needed. Game technology-based safety training platforms have the potential to overcome this problem in a virtual environment. One such platform is described in this paper - its characteristics are analysed and its possible contribution to safety training identified. This is developed and tested by means of a case study involving three major pieces of construction plant, which successfully demonstrates that the platform can improve the process and performance of the safety training involved in their operation. This research not only presents a new and useful solution to the safety training of construction operations, but illustrates the potential use of advanced technologies in solving construction industry problems in general. Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Dillard, J. P.
1981-01-01
The study objective was to develop or modify methods in an operational framework that would allow incorporation of satellite derived snow cover observations for prediction of snowmelt derived runoff. Data were reviewed and verified for five basins in the Pacific Northwest. The data were analyzed for up to a 6-year period ending July 1978, and in all cases cover a low, average, and high snow cover/runoff year. Cloud cover is a major problem in these springtime runoff analyses and have hampered data collection for periods of up to 52 days. Tree cover and terrain are sufficiently dense and rugged to have caused problems. The interpretation of snowlines from satellite data was compared with conventional ground truth data and tested in operational streamflow forecasting models. When the satellite snow-covered area (SCA) data are incorporated in the SSARR (Streamflow Synthesis and Reservoir Regulation) model, there is a definite but minor improvement.
Downhole vacuum cleans up tough fishing, milling jobs
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaLande, P.; Flanders, B.
1996-02-01
A unique tool developed to effect reverse circulation downhole is being used successfully in problem milling and fishing operations where conventional techniques fail to recover junk in the hole. Jointly developed by several major operators in conjunction with Baker Oil Tools, the patented Reverse Circulating Tool (RCT) acts as a downhole vacuum cleaner, catching and retaining debris circulated from the wellbore while allowing fishing, milling and washover operations to continue uninterrupted. As described in several case histories overviewed, the unique vacuuming action efficiently cleans up junk and debris in even the most difficult fishing and milling applications. Downhole operations proceedmore » normally, but without threat of damage from milled debris. Developers hold both mechanical and method patents on the RCT.« less
A variable-gain output feedback control design methodology
NASA Technical Reports Server (NTRS)
Halyo, Nesim; Moerder, Daniel D.; Broussard, John R.; Taylor, Deborah B.
1989-01-01
A digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach provides a control theory framework within which the operating range of a control law can be significantly extended. Furthermore, the approach avoids the major shortcomings of the conventional gain-scheduling techniques. The optimal variable gain output feedback control problem is solved by embedding the Multi-Configuration Control (MCC) problem, previously solved at ICS. An algorithm to compute the optimal variable gain output feedback control gain matrices is developed. The algorithm is a modified version of the MCC algorithm improved so as to handle the large dimensionality which arises particularly in variable-gain control problems. The design methodology developed is applied to a reconfigurable aircraft control problem. A variable-gain output feedback control problem was formulated to design a flight control law for an AFTI F-16 aircraft which can automatically reconfigure its control strategy to accommodate failures in the horizontal tail control surface. Simulations of the closed-loop reconfigurable system show that the approach produces a control design which can accommodate such failures with relative ease. The technique can be applied to many other problems including sensor failure accommodation, mode switching control laws and super agility.
Accelerating electron tomography reconstruction algorithm ICON with GPU.
Chen, Yu; Wang, Zihao; Zhang, Jingrong; Li, Lun; Wan, Xiaohua; Sun, Fei; Zhang, Fa
2017-01-01
Electron tomography (ET) plays an important role in studying in situ cell ultrastructure in three-dimensional space. Due to limited tilt angles, ET reconstruction always suffers from the "missing wedge" problem. With a validation procedure, iterative compressed-sensing optimized NUFFT reconstruction (ICON) demonstrates its power in the restoration of validated missing information for low SNR biological ET dataset. However, the huge computational demand has become a major problem for the application of ICON. In this work, we analyzed the framework of ICON and classified the operations of major steps of ICON reconstruction into three types. Accordingly, we designed parallel strategies and implemented them on graphics processing units (GPU) to generate a parallel program ICON-GPU. With high accuracy, ICON-GPU has a great acceleration compared to its CPU version, up to 83.7×, greatly relieving ICON's dependence on computing resource.
Induced abortion in sub-Saharan Africa.
Rogo, K O
1993-06-01
Unsafe abortions and their complications are a major cause of maternal mortality. Hospital based studies from most African countries confirm that up to 50% of maternal deaths are due to abortion. This paper reviews problem of induced abortion in sub-Saharan Africa. Issues of prevalence and prevention are addressed while acknowledging the need to review the legal regimes operating in these countries.
An Incremental Life-cycle Assurance Strategy for Critical System Certification
2014-11-04
for Safe Aircraft Operation Embedded software systems introduce a new class of problems not addressed by traditional system modeling & analysis...Platform Runtime Architecture Application Software Embedded SW System Engineer Data Stream Characteristics Latency jitter affects control behavior...do system level failures still occur despite fault tolerance techniques being deployed in systems ? Embedded software system as major source of
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khalil, C.N.
Formation of paraffin (wax) in cold deepwater flowlines is a major problem for offshore operators of such facilities. Petrobras faces this problem continuously in its deepwater operations in the Campos basin, offshore Brazil. Since 1990, through its Petrobras Research Center (CENPES), the company has developed, extensively field tested, and recently commercialized, a novel technique for chemically removing such wax depositions. The process involves mixing and introducing to the line, two inorganic salts and organic solvents. The ensuing chemical reaction--which both generates nitrogen and heats the inside of the blocked flowline--allows the solvent to dissolve and dislodge the buildup, which ismore » then flushed from the line. The process is called the Nitrogen Generation System (SGN). Petrobras/CENPES has recently formed a joint venture with the Brazilian service company Maritima Navegacao e Engenharia Ltda. to offer SGN services worldwide.« less
The SERENDIP 2 SETI project: Current status
NASA Technical Reports Server (NTRS)
Bowyer, C. S.; Werthimer, D.; Donnelly, C.; Herrick, W.; Lampton, M.
1991-01-01
Over the past 30 years, interest in extraterrestrial intelligence has progressed from philosophical discussion to rigorous scientific endeavors attempting to make contact. Since it is impossible to assess the probability of success and the amount of telescope time needed for detection, Search for Extraterrestrial Intelligence (SETI) Projects are plagued with the problem of attaining the large amounts of time needed on the world's precious few large radio telescopes. To circumvent this problem, the Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations (SERENDIP) instrument operates autonomously in a piggyback mode utilizing whatever observing plan is chosen by the primary observer. In this way, large quantities of high-quality data can be collected in a cost-effective and unobtrusive manner. During normal operations, SERENDIP logs statistically significant events for further offline analysis. Due to the large number of terrestrial and near-space transmitters on earth, a major element of the SERENDIP project involves identifying and rejecting spurious signals from these sources. Another major element of the SERENDIP Project (as well as most other SETI efforts) is detecting extraterrestrial intelligence (ETI) signals. Events selected as candidate ETI signals are studied further in a targeted search program which utilizes between 24 to 48 hours of dedicated telescope time each year.
A standard methodology for the analysis, recording, and control of verbal behavior
Drash, Philip W.; Tudor, Roger M.
1991-01-01
Lack of a standard methodology has been one of the major obstacles preventing advancement of behavior analytic research in verbal behavior. This article presents a standard method for the analysis, recording, and control of verbal behavior that overcomes several major methodological problems that have hindered operant research in verbal behavior. The system divides all verbal behavior into four functional response classes, correct, error, no response, and inappropriate behavior, from which all vocal responses of a subject may be classified and consequated. The effects of contingencies of reinforcement on verbal operants within each category are made immediately visible to the researcher as changes in frequency of response. Incorporating frequency of response within each category as the unit of response allows both rate and probability of verbal response to be utilized as basic dependent variables. This method makes it possible to record and consequate verbal behavior in essentially the same way as any other operant response. It may also facilitate an experimental investigation of Skinner's verbal response categories. PMID:22477629
Imbalanced Learning for Functional State Assessment
NASA Technical Reports Server (NTRS)
Li, Feng; McKenzie, Frederick; Li, Jiang; Zhang, Guangfan; Xu, Roger; Richey, Carl; Schnell, Tom
2011-01-01
This paper presents results of several imbalanced learning techniques applied to operator functional state assessment where the data is highly imbalanced, i.e., some function states (majority classes) have much more training samples than other states (minority classes). Conventional machine learning techniques usually tend to classify all data samples into majority classes and perform poorly for minority classes. In this study, we implemented five imbalanced learning techniques, including random undersampling, random over-sampling, synthetic minority over-sampling technique (SMOTE), borderline-SMOTE and adaptive synthetic sampling (ADASYN) to solve this problem. Experimental results on a benchmark driving lest dataset show thai accuracies for minority classes could be improved dramatically with a cost of slight performance degradations for majority classes,
NASA Technical Reports Server (NTRS)
Degnan, J. J.; Walker, H. E.; Peruso, C. J.; Johnson, E. H.; Klein, B. J.; Mcelroy, J. H.
1972-01-01
The systems and techniques which were utilized in the experiment to establish an air-to-ground CO2 laser heterodyne link are described along with the successes and problems encountered when the heterodyne receiver and laser transmitter package were removed from the controlled environment of the laboratory. Major topics discussed include: existing systems and the underlying principles involved in their operation; experimental techniques and optical alignment methods which were found to be useful; theoretical calculations of signal strengths expected under a variety of test conditions and in actual flight; and the experimental results including problems encountered and their possible solutions.
NASA Astrophysics Data System (ADS)
Beddow, B.; Roberts, C.; Rankin, J.; Bloch, A.; Peizer, J.
1981-01-01
The National Accident Sampling System (NASS) is described. The study area discussed is one of the original ten sites selected for NASS implementation. In addition to collecting data from the field, the original ten sites address questions of feasibility of the plan, projected results of the data collection effort, and specific operational topics, e.g., team size, sampling requirements, training approaches, quality control procedures, and field techniques. Activities and results of the first three years of the project, for both major tasks (establishment and operation) are addressed. Topics include: study area documentation; team description, function and activities; problems and solutions; and recommendations.
Australia's insurance crisis and the inequitable treatment of self-employed midwives.
Canil, Milena
2008-05-29
Based upon a review of articles published in Australia's major newspapers over the period January 2001 to December 2005, a case study approach has been used to investigate why, when compared with other small business operators, including medical specialists, Australian governments have appeared reluctant to protect the economic viability of the businesses of self-employed midwives. Theories of agenda setting and structuralism have been used to explore that inequity. What has emerged is a picture of the complex of factors that may have operated, and may be continuing to operate, to shape the policy agenda and thus prevent solutions to the insurance problems of self-employed midwives being found.
Australia's insurance crisis and the inequitable treatment of self-employed midwives
Canil, Milena
2008-01-01
Based upon a review of articles published in Australia's major newspapers over the period January 2001 to December 2005, a case study approach has been used to investigate why, when compared with other small business operators, including medical specialists, Australian governments have appeared reluctant to protect the economic viability of the businesses of self-employed midwives. Theories of agenda setting and structuralism have been used to explore that inequity. What has emerged is a picture of the complex of factors that may have operated, and may be continuing to operate, to shape the policy agenda and thus prevent solutions to the insurance problems of self-employed midwives being found. PMID:18507866
Mitigation of Power Quality Problems in Grid-Interactive Distributed Generation System
NASA Astrophysics Data System (ADS)
Bhende, C. N.; Kalam, A.; Malla, S. G.
2016-04-01
Having an inter-tie between low/medium voltage grid and distributed generation (DG), both exposes to power quality (PQ) problems created by each other. This paper addresses various PQ problems arise due to integration of DG with grid. The major PQ problems are due to unbalanced and non-linear load connected at DG, unbalanced voltage variations on transmission line and unbalanced grid voltages which severely affect the performance of the system. To mitigate the above mentioned PQ problems, a novel integrated control of distribution static shunt compensator (DSTATCOM) is presented in this paper. DSTATCOM control helps in reducing the unbalance factor of PCC voltage. It also eliminates harmonics from line currents and makes them balanced. Moreover, DSTATCOM supplies the reactive power required by the load locally and hence, grid need not to supply the reactive power. To show the efficacy of the proposed controller, several operating conditions are considered and verified through simulation using MATLAB/SIMULINK.
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.
Weathering the Storm - GOCE Flight Operations in 2010
NASA Astrophysics Data System (ADS)
Steiger, C.; Da Costa, A.; Floberghagen, R.; Fehringer, M.; Emanuelli, P. P.
2011-07-01
ESA's Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) was successfully launched on 17th March 2009. The mission is controlled by ESA's European Space Operations Centre (ESOC) in Darmstadt, Germany. Following completion of commissioning, routine operations started in September 2009, keeping the S/C in drag-free mode at an altitude of 259.6 km. Operations are driven by the unique aspects of the mission, in particular the very low altitude and the high complexity of GOCE's drag- free control system. Following a general introduction, the main focus is put on the special events of 2010, when science operations were interrupted for several months due to problems with the main platform computer. These anomalies presented a major challenge, requiring to operate the spacecraft "in the blind" with no status information available, and extensive modifications of the on-board software to recover the mission.
Deep Space Network (DSN), Network Operations Control Center (NOCC) computer-human interfaces
NASA Technical Reports Server (NTRS)
Ellman, Alvin; Carlton, Magdi
1993-01-01
The Network Operations Control Center (NOCC) of the DSN is responsible for scheduling the resources of DSN, and monitoring all multi-mission spacecraft tracking activities in real-time. Operations performs this job with computer systems at JPL connected to over 100 computers at Goldstone, Australia and Spain. The old computer system became obsolete, and the first version of the new system was installed in 1991. Significant improvements for the computer-human interfaces became the dominant theme for the replacement project. Major issues required innovating problem solving. Among these issues were: How to present several thousand data elements on displays without overloading the operator? What is the best graphical representation of DSN end-to-end data flow? How to operate the system without memorizing mnemonics of hundreds of operator directives? Which computing environment will meet the competing performance requirements? This paper presents the technical challenges, engineering solutions, and results of the NOCC computer-human interface design.
Collision Avoidance Short Course Part I: Theory
NASA Technical Reports Server (NTRS)
Hejduk, Matthew D.
2017-01-01
Satellite conjunction assessment is perhaps the fastest-growing area in space situational awareness and protection, with military, civil, and commercial satellite owner operators embracing more and more sophisticated processes to avoid the avoidable namely collisions between high-value space assets and orbital debris. NASA and CNES have collaborated to offer an introductory short course on all the major aspects of the conjunction assessment problem. This half-day course will cover satellite conjunction dynamics and theory, JSpOC conjunction data products, major risk assessment parameters and plots, conjunction remediation decision support, and present and future challenges. This briefing represents the NASA portion of the course.
[Working conditions in operating rooms].
Kułagowska, Ewa
2007-01-01
The aim of this study was to get acquainted with the opinions of the nursing staff on working conditions at their workplace. The study was carried out in a group of 398 nurses working in various kinds of operating rooms at 11 public hospitals. A questionnaire was used as a major tool of this study. The questionnaires were filled in by 259 operating room nurses (circulating nurses) and 139 nurse-anesthetists. The collected data show that working conditions in operating rooms do not ensure safety of the nursing staff at work. The main sources of problems are: work organization, technical factors, work equipment, work space, knowledge of hazards and strenuous factors among nurses, ways of preventing and/or limiting them. These elements are serious occupational risk factors influencing the work process and health status of nurses.
NASA Technical Reports Server (NTRS)
Happell, Nadine; Miksell, Steve; Carlisle, Candace
1989-01-01
A major barrier in taking expert systems from prototype to operational status involves instilling end user confidence in the operational system. The software of different life cycle models is examined and the advantages and disadvantages of each when applied to expert system development are explored. The Fault Isolation Expert System for Tracking and data relay satellite system Applications (FIESTA) is presented as a case study of development of an expert system. The end user confidence necessary for operational use of this system is accentuated by the fact that it will handle real-time data in a secure environment, allowing little tolerance for errors. How FIESTA is dealing with transition problems as it moves from an off-line standalone prototype to an on-line real-time system is discussed.
NASA Technical Reports Server (NTRS)
Happell, Nadine; Miksell, Steve; Carlisle, Candace
1989-01-01
A major barrier in taking expert systems from prototype to operational status involves instilling end user confidence in the operational system. The software of different life cycle models is examined and the advantages and disadvantages of each when applied to expert system development are explored. The Fault Isolation Expert System for Tracking and data relay satellite system Applications (FIESTA) is presented as a case study of development of an expert system. The end user confidence necessary for operational use of this system is accentuated by the fact that it will handle real-time data in a secure environment, allowing little tolerance for errors. How FIESTA is dealing with transition problems as it moves from an off-line standalone prototype to an on-line real-time system is discussed.
Research into command, control, and communications in space construction
NASA Technical Reports Server (NTRS)
Davis, Randal
1990-01-01
Coordinating and controlling large numbers of autonomous or semi-autonomous robot elements in a space construction activity will present problems that are very different from most command and control problems encountered in the space business. As part of our research into the feasibility of robot constructors in space, the CSC Operations Group is examining a variety of command, control, and communications (C3) issues. Two major questions being asked are: can we apply C3 techniques and technologies already developed for use in space; and are there suitable terrestrial solutions for extraterrestrial C3 problems? An overview of the control architectures, command strategies, and communications technologies that we are examining is provided and plans for simulations and demonstrations of our concepts are described.
ERIC Educational Resources Information Center
1982
During the first year of operation under the Act, major problems encountered focused on: (1) defining the terms "full time equivalent" (FTE) student for purposes of per capita financial support to approved institutions; (2) the planning, conduct, and analyses of feasibility studies to better specify the constituent population and their…
The Problem of Discipline/Control and Security in Our Schools. Position Paper, Number 1.
ERIC Educational Resources Information Center
National Urban League, Inc., New York, NY.
A survey in the fall of 1969 revealed that of the 51 major cities which responded to a questionnaire, only four did not employ their own security officers or use city policemen in daily school operations. It is contended that it is impossible for a favorable climate for learning to be established within this type of environment. Further, it is…
While the vast majority of operational air-pollution networks across the world are designed to measure relevant metrics at the surface, the air pollution problem is a three-dimensional phenomenon. The lack of adequate observations aloft to routinely characterize the nature of ai...
ADDJUST-A View of the First 25 Years
NASA Technical Reports Server (NTRS)
Nieberding, Joe; Williams, Craig H.
2015-01-01
Various technologies and innovative launch operations were developed during the 50 years of the Centaur upper stage—the first launch vehicle to use high performing liquid hydrogen fuel. One innovation was “ADDJUST”, which enabled the successful negotiation of upper level winds measured only hours before launch. Initial causes for its creation, development, and operation during countdown are detailed. Problem definition, wind measuring/monitoring process, pitch and yaw steering coefficient generation, loads analysis, angle of attack, major risks/concerns, and anecdotal recollections are provided. Launch availability improved from as low as 55 to 95 percent due to ADDJUST, which is still in use.
Structural dynamics verification facility study
NASA Technical Reports Server (NTRS)
Kiraly, L. J.; Hirchbein, M. S.; Mcaleese, J. M.; Fleming, D. P.
1981-01-01
The need for a structural dynamics verification facility to support structures programs was studied. Most of the industry operated facilities are used for highly focused research, component development, and problem solving, and are not used for the generic understanding of the coupled dynamic response of major engine subsystems. Capabilities for the proposed facility include: the ability to both excite and measure coupled structural dynamic response of elastic blades on elastic shafting, the mechanical simulation of various dynamical loadings representative of those seen in operating engines, and the measurement of engine dynamic deflections and interface forces caused by alternative engine mounting configurations and compliances.
The high intensity solar cell - Key to low cost photovoltaic power
NASA Technical Reports Server (NTRS)
Sater, B. L.; Goradia, C.
1975-01-01
This paper discusses the problems associated with conventional solar cells at high intensities and presents the design considerations and performance characteristics of the 'high intensity' (HI) solar cell which appears to eliminate the major problems. Test data obtained at greater than 250 AM1 suns gave a peak output power density of 2 W per sq cm at an efficiency exceeding 6% with an unoptimized cell operating at over 100 C. It appears that operation at 1000 AM1 suns at efficiencies greater than 10% is possible. At 1000 AM1 suns and 10% efficiency, the HI cell manufacturing cost is estimated to be $0.25/watt, with multi-megawatt annual production capability already existing within the industrial sector. A high intensity solar system was also analyzed to determine its cost effectiveness and to assess the benefits of further improving HI cell efficiency.
Stacey, Glyn N
2011-01-01
Microbial contamination is a major issue in cell culture, but there are a range of procedures which can be adopted to prevent or eliminate contamination. Contamination may arise from the operator and the laboratory environment, from other cells used in the laboratory, and from reagents. Some infections may present a risk to laboratory workers: containment and aseptic technique are the key defence against such risks. Remedial management of suspected infection may simply mean discarding a single potentially infected culture. However, if a more widespread problem is identified, then all contaminated cultures and associated unused media that have been opened during this period should be discarded, equipment should be inspected and cleaned, cell culture operations reviewed, and isolation from other laboratories instituted until the problem is solved. Attention to training of staff, laboratory layout, appropriate use of quarantine for new cultures or cell lines, cleaning and maintenance, and quality control are important factors in preventing contamination in cell culture laboratories.
Cooperative Robots to Observe Moving Targets: Review.
Khan, Asif; Rinner, Bernhard; Cavallaro, Andrea
2018-01-01
The deployment of multiple robots for achieving a common goal helps to improve the performance, efficiency, and/or robustness in a variety of tasks. In particular, the observation of moving targets is an important multirobot application that still exhibits numerous open challenges, including the effective coordination of the robots. This paper reviews control techniques for cooperative mobile robots monitoring multiple targets. The simultaneous movement of robots and targets makes this problem particularly interesting, and our review systematically addresses this cooperative multirobot problem for the first time. We classify and critically discuss the control techniques: cooperative multirobot observation of multiple moving targets, cooperative search, acquisition, and track, cooperative tracking, and multirobot pursuit evasion. We also identify the five major elements that characterize this problem, namely, the coordination method, the environment, the target, the robot and its sensor(s). These elements are used to systematically analyze the control techniques. The majority of the studied work is based on simulation and laboratory studies, which may not accurately reflect real-world operational conditions. Importantly, while our systematic analysis is focused on multitarget observation, our proposed classification is useful also for related multirobot applications.
Ghosh, Sumanta Kumar
2013-07-01
Major pancreatic injury following blunt abdominal trauma by itself is a relatively rare occurrence, and in vast majority of cases (95%) it is associated with injury to adjacent major vessels and organs; thus making isolated major pancreatic injury even rarer. While most pancreatic injuries are managed by simple measures like debridement and drainage, complex proximal injury poses surgical challenge regarding surgical skill and judgement. Disproportionate approach at any stage of management can contribute to high mortality and morbidity. Emergency pancreatoduodenectomy plays a limited but important role in managing serious trauma to proximal pancreas and duodenum. Author presents a case where isolated injury to head of pancreas required emergency pancreatoduodenectomy. After a bizarre road accident, a middle aged male underwent emergency laparotomy for intraperitoneal bleeding and during exploration a deep transverse laceration with ampullary disruption was found in the head of the organ. Duodenum in all its part was intact and there was no other injury. The nature and site of injury made emergency pancreatoduodenectomy the only viable option. Leaking pancreatojejunostomy enhances infective complications that lead to late mortality. To circumvent this problem there is enthusiasm for staged surgery with resection and tube pancreatostomy in first stage, leaving the difficult anastomosis for a later date, However, if the patient is haemodynamically stable and operated reasonably early, one stage pancreatoduodenectomy gives good result and avoids repeating surgery with inherent problems and reduces hospital stay. For successful management of pancreatic trauma it is essential to make early diagnosis of duct disruption, with sound application of operative skill and judgement by treating surgeon.
Application of supercomputers to computational aerodynamics
NASA Technical Reports Server (NTRS)
Peterson, V. L.
1984-01-01
Computers are playing an increasingly important role in the field of aerodynamics such that they now serve as a major complement to wind tunnels in aerospace research and development. Factors pacing advances in computational aerodynamics are identified, including the amount of computational power required to take the next major step in the discipline. Example results obtained from the successively refined forms of the governing equations are discussed, both in the context of levels of computer power required and the degree to which they either further the frontiers of research or apply to problems of practical importance. Finally, the Numerical Aerodynamic Simulation (NAS) Program - with its 1988 target of achieving a sustained computational rate of 1 billion floating point operations per second and operating with a memory of 240 million words - is discussed in terms of its goals and its projected effect on the future of computational aerodynamics.
Application of ERTS-1 data to the protection and management of New Jersey's coastal environment
NASA Technical Reports Server (NTRS)
Yunghans, R. S. (Principal Investigator); Feinberg, E. B.; Stitt, J. A.; Mairs, R. L.; Macomber, R. T.; Stanczuk, D.; Wobber, F. J.
1974-01-01
The author has identified the following significant results. The principal thrust of this ERTS-1 experiment is to develop quasi-operational information products from analysis of ERTS-1 imagery and collateral aerial photography and to apply these products to the practical regulation, protection, and management of New Jersey's coastal environment. Incorporated into this goal is the development of procedures for the operational use of ERTS-1 data products within New Jersey's Department of Environmental Protection. Analysis and product preparation for operational needs has centered on four major coastal resource problem areas: detection of land use changes in the coastal zone; siting of ocean outfalls; monitoring of offshore waste disposal; and calculation of recession rates along the Atlantic Shore. The relative utility and estimated monetary benefits derived from ERTS and aircraft imagery for each problem area have been determined. Of equal importance is the development to a capability within the State to use and understand remote sensor-derived information, and the application of this information to meet the requirements of current and anticipated coastal zone legislation.
NASA Astrophysics Data System (ADS)
Norazam Yasin, Mohd; Mohamad Zin, Rosli; Halid Abdullah, Abd; Shafiq Mahmad, Muhammad; Fikri Hasmori, Muhammad
2017-11-01
From time to time, the maintenance works become more challenging due to construction of new building and also aging of the existing buildings. University buildings without any exception require proper maintenance services to support their function requirements and this can be considered as major responsibilities to be fulfilled by the maintenance department in the universities. Maintenance department specifically will face various kinds of problems in their operation works and thus this might influence the maintenance work operations itself. This study purposely to identify the common problem facing by the maintenance department and also to examine the current status of the maintenance department. In addition, this study would also propose any suitable approach that could be implemented to overcome the problem facing by the maintenance department. To achieve the objectives of this study, a combination of deep literature study and carrying out a survey is necessary. Literature study aimed to obtain deeper information about this study, meanwhile a survey aimed at identifying the common problem facing by the maintenance department and also to provide the information of the maintenance department’s organization. Several methods will be used in analyzing the data obtained through the survey, including Microsoft Office Excel and also using mean index formula. This study has identified three categories of problem in the maintenance department, which are management problems, human resource problem, and technical problems. Following the findings, several solutions being proposed which can be implemented as the solution to the problem facing. These suggestions have the potential to improve the maintenance department work efficiency, thus could help to increase the department productivity.
Examination, evaluation and repair of laminated wood blades after service on the Mod-OA wind turbine
NASA Technical Reports Server (NTRS)
Faddoul, J. R.
1983-01-01
Laminated wood blades were designed, fabricated, and installed on a 200-KW wind turbine (Mod-OA). The machine uses a two-blade rotor with a diameter of 38.1 m (125 ft). Each blade weights less than 1361 kg (3000 lb). After operating in the field, two blade sets were returned for inspection. One set had been in Hawaii for 17 months (7844 hr of operation) and the other had been at Block Island, Rhode Island, for 26 months (22 months operating - 7564 hr). The Hawaii set was returned because of one of the studs that holds the blade to the hub had failed. This was found to be caused by a combination of improper installation and inadequate corrosion protection. No other problems were found. The broken stud (along with four others that were badly corroded) was replaced and the blades are now in storage. The Block Island set of blades was returned at the completion of the test program, but one blade was found to have developed a crack in the leading edge along the entire span. This crack was found to be the result of a manufacturing process problem but was not structurally critical. When a load-deflection test was conducted on the cracked blade, the response was identical to that measured before installation. In general, the laminate quality of both blade sets was excellent. No significant internal delamination or structural defects were found in any blade. The stud bonding process requires close tolerance control and adequate corrosion protection, but studs can be removed and replaced without major problems. Moisture content stabilization does not appear to be a problem, and laminated wood blades are satisfactory for long-term operation on Mod-OA wind turbines.
Analysis of Disaster Preparedness Planning Measures in DoD Computer Facilities
1993-09-01
city, stae, aod ZP code) 10 Source of Funding Numbers SProgram Element No lProject No ITask No lWork Unit Accesion I 11 Title include security...Computer Disaster Recovery .... 13 a. PC and LAN Lessons Learned . . ..... 13 2. Distributed Architectures . . . .. . 14 3. Backups...amount of expense, but no client problems." (Leeke, 1993, p. 8) 2. Distributed Architectures The majority of operations that were disrupted by the
Combat Mission Training Research at the 58th Special Operations Wing: A Summary
1998-07-01
Air Force Base during 1995-1997. The first study examined the relationship between crew resource management ( CRM ) processes and mission performance for...next three sections, we summarize the three major empirical studies that were conducted: (a) measuring crew resource management ( CRM ) behaviors... customized measurement procedures and data collection instruments. At the squadron level, there are two problems in implementing an effective CRM training
NASA Technical Reports Server (NTRS)
Johnston, R. S.; Dietlein, L. F.; Michel, E. L.
1975-01-01
The paper discusses the medical program of the Skylab missions. The major medical systems discussed include the food system, the waste-management system, the personal-hygiene system, and the inflight medical support system. The life-sciences experiments conducted on Skylab are reviewed. These dealt with the cardiovascular system, mineral balance and bioassay of fluids, sleep, blood, metabolic activity, vestibular function, and time and motion studies. The medical operations were accomplished with only minor problems.
Multifunction Multiband Airborne Radio Architecture Study.
1982-01-01
30 to 88, 108 to 156, and 255 to 400 MHz band allocations . (ii) On designated operating channels: two in the 225 to 400 MHz bandwidth, one in each of...altimeter, direction finding, and relay. 2.2 BASELINE SYSTEM APPROACH This subsection describes the TRW-proposed baseline design for the MFBARS system...problem and SINCGARS application. Major efforts were directed toward reducing the overall costs while retaining required performance. Significantly, cost
NASA Technical Reports Server (NTRS)
New, S. R.
1981-01-01
The multiplexer-demultiplexer (MDM) project included the design, documentation, manufacture, and testing of three MDM Data Systems. The equipment is contained in 59 racks, and includes more than 3,000 circuit boards and 600 microprocessors. Spares, circuit card testers, a master set of programmable integrated circuits, and a program development system were included as deliverables. All three MDM's were installed, and were operationally tested. The systems performed well with no major problems. The progress and problems analysis, addresses schedule conformance, new technology, items awaiting government approval, and project conclusions are summarized. All contract modifications are described.
NASA Astrophysics Data System (ADS)
New, S. R.
1981-06-01
The multiplexer-demultiplexer (MDM) project included the design, documentation, manufacture, and testing of three MDM Data Systems. The equipment is contained in 59 racks, and includes more than 3,000 circuit boards and 600 microprocessors. Spares, circuit card testers, a master set of programmable integrated circuits, and a program development system were included as deliverables. All three MDM's were installed, and were operationally tested. The systems performed well with no major problems. The progress and problems analysis, addresses schedule conformance, new technology, items awaiting government approval, and project conclusions are summarized. All contract modifications are described.
Development of a liquid metal slip ring
NASA Technical Reports Server (NTRS)
Weinberger, S. M.
1972-01-01
A liquid metal slip ring/solar orientation mechanism was designed and a model tested. This was a follow-up of previous efforts for the development of a gallium liquid metal slip ring in which the major problem was the formation and ejection of debris. A number of slip ring design approaches were studied. The probe design concept was fully implemented with detail drawings and a model was successfully tested for dielectric strength, shock vibration, acceleration and operation. The conclusions are that a gallium liquid metal slip ring/solar orientation mechanism is feasible and that the problem of debris formation and ejection has been successfully solved.
REIMR: A Process for Utilizing Propulsion-Oriented 'Lessons-Learned' to Mitigate Development Risk
NASA Technical Reports Server (NTRS)
Ballard, Richard O.; Brown, Kendall K.
2005-01-01
This paper is a summary overview of a study conducted a t the NASA Marshall Space Flight Center (MSFC) during the initial phases of the Space Launch Initiative (SLI) program to evaluate a large number of technical problems associated with the design, development, test, evaluation and operation of several major liquid propellant rocket engine systems (i.e., SSME, Fastrac, J-2, F-1). The results of this study was the identification of the "Fundamental Root Causes" that enabled the technical problems to manifest, and practices that can be implemented to prevent them from recurring in future engine development efforts. This paper will discus the Fundamental Root Causes, cite some examples of how the technical problems arose from them, and provide a discussion of how they can be mitigated or avoided.
Intelligent laser soldering inspection and process control
NASA Technical Reports Server (NTRS)
Vanzetti, Riccardo
1987-01-01
Component assembly on printed circuitry keeps making giant strides toward denser packaging and smaller dimensions. From a single layer to multilayer, from through holes to surface mounted components and tape applied bonds, unrelenting progress results in new, difficult problems in assembling, soldering, inspecting and controlling the manufacturing process of the new electronics. Among the major problems are the variables introduced by human operators. The small dimensions and the tight assembly tolerances are now successfully met by machines which are faster and more precise than the human hand. The same is true for soldering. But visual inspection of the solder joints is now so severely limited by the ever shrinking area accessible to the human eye that the inspector's diagnosis cannot be trusted any longer. Solutions to correcting these problems are discussed.
Collision Avoidance "Short Course" Part III: CA Role in Changing Space Flight Environment
NASA Technical Reports Server (NTRS)
Newman, Lauri
2017-01-01
Satellite conjunction assessment is perhaps the fastest-growing area in space situational awareness and protection, with military, civil, and commercial satellite owner operators embracing more and more sophisticated processes to avoid the avoidable namely collisions between high-value space assets and orbital debris. NASA and CNES have collaborated to offer an introductory short course on all the major aspects of the conjunction assessment problem. This half-day course will cover satellite conjunction dynamics and theory, JSpOC conjunction data products, major risk assessment parameters and plots, conjunction remediation decision support, and present and future challenges. This briefing represents the NASA portion of the course.
STARPAHC - Operational findings. [Space Technology Applied to Rural Papago Advanced Health Care
NASA Technical Reports Server (NTRS)
Belasco, N.; Pool, S. L.
1976-01-01
Delivery of quality health care to passengers of extended-mission spacecraft and to remote populations on earth (a major national problem) requires extending the knowledge and skills of the physician many kilometers distant from his physical location. The STARPAHC telemedicine system accomplishes this by using physician's assistants complemented with space technology in communications, data handling, and systems engineering. It is presently in operation and undergoing a 2-year evaluation on the Papago Indian Reservation, Arizona. Results have established its feasibility as a solution for remote area health care on earth, while providing information useful to the planners of advanced manned spacecraft missions.
Optics and materials research for controlled radiant energy transfer in buildings
NASA Astrophysics Data System (ADS)
Goldner, R. B.
1983-11-01
The overall objective of the Tufts research program was to identify and attempt to solve some of the key materials problems associated with practical approaches for achieving controlled radiant energy transfer (CRET) through building windows and envelopes, so as to decrease heating and cooling loads in buildings. Major accomplishments included: the identification of electrochromic (EC)-based structures as the preferred structures for achieving CRET; the identification of modulated reflectivity as the preferred mode of operation for EC-based structures; demonstration of the feasibility of operating EC-materials in a modulated R(lambda) mode; and demonstration of the applicability of free electron model to colored polycrystalline WO3 films.
Artificial intelligence applied to process signal analysis
NASA Technical Reports Server (NTRS)
Corsberg, Dan
1988-01-01
Many space station processes are highly complex systems subject to sudden, major transients. In any complex process control system, a critical aspect of the human/machine interface is the analysis and display of process information. Human operators can be overwhelmed by large clusters of alarms that inhibit their ability to diagnose and respond to a disturbance. Using artificial intelligence techniques and a knowledge base approach to this problem, the power of the computer can be used to filter and analyze plant sensor data. This will provide operators with a better description of the process state. Once a process state is recognized, automatic action could be initiated and proper system response monitored.
Rectus sheath catheter infusions for post-operative pain management.
Layzell, Mandy
2014-06-24
Managing pain following major abdominal surgery remains a challenge. Traditionally, patient-controlled analgesia (PCA) or epidural analgesia have been used, which have improved post-operative pain and the patient experience, but have presented some problems in recovery. PCA can cause adverse effects, including sedation, nausea, vomiting, and prolonged gastric ileus. While epidurals do have some advantages over PCA, there are risks involved related to catheter insertion and adverse effects, such as hypotension and motor blocks which limit mobility. This article examines rectus sheath catheter infusions, a relatively new and alternative technique to epidural analgesia, and presents some early audit data related to pain scores, analgesic use and mobility.
Dynamic emulation modelling for the optimal operation of water systems: an overview
NASA Astrophysics Data System (ADS)
Castelletti, A.; Galelli, S.; Giuliani, M.
2014-12-01
Despite sustained increase in computing power over recent decades, computational limitations remain a major barrier to the effective and systematic use of large-scale, process-based simulation models in rational environmental decision-making. Whereas complex models may provide clear advantages when the goal of the modelling exercise is to enhance our understanding of the natural processes, they introduce problems of model identifiability caused by over-parameterization and suffer from high computational burden when used in management and planning problems. As a result, increasing attention is now being devoted to emulation modelling (or model reduction) as a way of overcoming these limitations. An emulation model, or emulator, is a low-order approximation of the process-based model that can be substituted for it in order to solve high resource-demanding problems. In this talk, an overview of emulation modelling within the context of the optimal operation of water systems will be provided. Particular emphasis will be given to Dynamic Emulation Modelling (DEMo), a special type of model complexity reduction in which the dynamic nature of the original process-based model is preserved, with consequent advantages in a wide range of problems, particularly feedback control problems. This will be contrasted with traditional non-dynamic emulators (e.g. response surface and surrogate models) that have been studied extensively in recent years and are mainly used for planning purposes. A number of real world numerical experiences will be used to support the discussion ranging from multi-outlet water quality control in water reservoir through erosion/sedimentation rebalancing in the operation of run-off-river power plants to salinity control in lake and reservoirs.
Multitasking operating systems for microprocessors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cramer, T.
1981-01-01
Microprocessors, because of their low cost, low power consumption, and small size, have caused an explosion in the number of innovative computer applications. Although there is a great deal of variation in microprocessor applications software, there is relatively little variation in the operating-system-level software from one application to the next. Nonetheless, operating system software, especially when multitasking is involved, can be very time consuming and expensive to develop. The major microprocessor manufacturers have acknowledged the need for operating systems in microprocessor applications and are now supplying real-time multitasking operating system software that is adaptable to a wide variety of usermore » systems. Use of this existing operating system software will decrease the number of redundant operating system development efforts, thus freeing programmers to work on more creative and productive problems. This paper discusses the basic terminology and concepts involved with multitasking operating systems. It is intended to provide a general understanding of the subject, so that the reader will be prepared to evaluate specific operating system software according to his or her needs. 2 references.« less
Decision-making and problem-solving methods in automation technology
NASA Technical Reports Server (NTRS)
Hankins, W. W.; Pennington, J. E.; Barker, L. K.
1983-01-01
The state of the art in the automation of decision making and problem solving is reviewed. The information upon which the report is based was derived from literature searches, visits to university and government laboratories performing basic research in the area, and a 1980 Langley Research Center sponsored conferences on the subject. It is the contention of the authors that the technology in this area is being generated by research primarily in the three disciplines of Artificial Intelligence, Control Theory, and Operations Research. Under the assumption that the state of the art in decision making and problem solving is reflected in the problems being solved, specific problems and methods of their solution are often discussed to elucidate particular aspects of the subject. Synopses of the following major topic areas comprise most of the report: (1) detection and recognition; (2) planning; and scheduling; (3) learning; (4) theorem proving; (5) distributed systems; (6) knowledge bases; (7) search; (8) heuristics; and (9) evolutionary programming.
Nuclear Waste: Defense Waste Processing Facility-Cost, Schedule, and Technical Issues.
1992-06-17
gallons of high-level radioactive waste stored in underground tanks at the savannah major facility involved Is the Defense Waste Processing Facility ( DwPF ...As a result of concerns about potential problems with the DWPF and delays in its scheduled start-up, the Chairman of the Environment, Energy, and...Natural Resources Subcommittee, House Committee on Government Operations, asked GAO to review the status of the DWPF and other facilities. This report
The Utilization of the Behavioral Sciences in Long Range Forecasting and Policy Planning
1973-07-30
73 - December 31, 1973. The report will be divided into six major sections. The first will describe the analysis initiated and completed dur- ing...the half year. Results of special significance will be highlighted. Methodological problems that have arisen during the analysis will be discussed...of this analysis has been the development of a modular computer simula- tion of such operations. The oil simulation module Is then to be used
William T. Plass; Willis G. Vogel
1973-01-01
A survey of 39 surface-mine sites in southern West Virginia showed that most of the spoils from current mining operations had a pH of 5.0 or higher. Soil-size material averaged 37 percent of the weight of the spoils sampled. A major problem for the establishment of vegetation was a deficiency of nitrogen and phosphorus. This can be corrected with additions of...
Guidelines for Selecting Control and Treatment Options for Contaminated Dredged Material.
1986-09-01
application of the DMASS to selection of control/treatment alternatives. The Totem Ocean Trailer Express Terminal Project in the Blair Waterway was...resuspension to a minimum. Limitations may be placed on levels of suspended solids when even normal dredging operations occur around public areas or coral ... reefs or during certain periods in the life cycle of a specific marine species (Lunz, Clark, and Fredette 1984). However, the major problems from
Photonic integrated transmitter and receiver for NG-PON2
NASA Astrophysics Data System (ADS)
Tavares, Ana; Lopes, Ana; Rodrigues, Cláudio; Mãocheia, Paulo; Mendes, Tiago; Brandão, Simão.; Rodrigues, Francisco; Ferreira, Ricardo; Teixeira, António
2014-08-01
In this paper the authors present a monolithic Photonic Integrated Circuit which includes a transmitter and a receiver for NG-PON2. With this layout it is possible to build an OLT and, by redesigning some filters, also an ONU. This technology allows reducing the losses in the transmitter and in the receiver, increasing power budget, and also reducing the OEO conversions, which has been a major problem that operators want to surpass.
Karimi, D; Henry, J; Mann, D D
2012-10-01
Tractor operators are prone to neck and back discomfort and disorders. It is well known that awkward posture is a major contributor to this problem. Previous studies have investigated the prevalence of awkward posture and the resulting discomfort and disorders among tractor operators. They have also suggested various ways to mitigate this problem. With the introduction of new autosteer guidance systems, the tractor operator is relieved from the task of steering the tractor for most of the time during field work. Therefore, it is expected that the operator's posture will change. The goal of this study was to investigate the changes in the eye-glance behavior and posture of tractor operators as a result of using autosteer guidance systems. An eye-tracking system and a camcorder were used to record the eye-glance behavior and posture of 13 tractor operators as they performed seeding operations. The experiment with each operator consisted of two sessions. In one session, the operator used an autosteer system, while in the other session the operator steered the tractor manually. Analysis of the data showed that the eye-glance behavior and posture of the operators were significantly different between the autosteer and manual steering sessions. With the autosteer system, the operators spent less time in an awkward posture, and they changed their posture less frequently. However, even with the autosteer system, the operators spent 1/3 of their time in an awkward posture. Subjective feedback from the operators indicated that more than half of them experienced back or neck/shoulder discomfort during or after seeding. It is essential that the recommendations of the previous studies, such as using large rear-view mirrors or a rotating tractor seat, be evaluated when the operator is using an autosteer system. Other tools, such as video cameras that show the attached equipment, should also be tested to evaluate their effectiveness in reducing the operator's exposure to awkward postures.
Installation and checkout of the DOE/NASA Mod-1 2000-kW wind turbine generator
NASA Technical Reports Server (NTRS)
Puthoff, R. L.; Collins, J. L.; Wolf, R. A.
1980-01-01
The paper describes the DOE/NASA Mod-1 wind turbine generator, its assembly and testing, and its installation at Boone, North Carolina. The paper concludes with performance data taken during the initial tests conducted on the machine. The successful installation and initial operation of the Mod-1 wind turbine generator has had the following results: (1) megawatt-size wind turbines can be operated satisfactorily on utility grids; (2) the structural loads can be predicted by existing codes; (3) assembly of the machine on top of the tower presents no major problem; (4) large blades 100 ft long can be transported long distances and over mountain roads; and (5) operating experience and performance data will contribute substantially to the design of future low-cost wind turbines.
NASA Technical Reports Server (NTRS)
Hagood, J. T.
1973-01-01
Acceptance tests were conducted at Kennedy Space Center of the Saturn Vehicle Workshop Spacecraft Access Arm and related equipment. The tests were conducted to prove complete system capability to operate satisfactorily under conditions required to support spacecraft operations and activities. The SVWS Access Arm, serial number AA-09-03, is a Command Module Service Arm, S/A 9, which was removed from the mobile launcher and modified to support the SVWS operations. The C/M environmental chamber was removed and a completely new chamber was installed. The retract system was redesigned to remove the automatic/remote control capability and replaced with a local manual control. The SVWS Access Arm System was successfully tested and supported spacecraft processing without major problems.
Fügener, Andreas; Schiffels, Sebastian; Kolisch, Rainer
2017-03-01
The planning of surgery durations is crucial for efficient usage of operating theaters. Both planning too long and too short durations for surgeries lead to undesirable consequences, e.g. idle time, overtime, or rescheduling of surgeries. We define these consequences as operating room inefficiency. The overall objective of planning surgery durations is to minimize expected operating room inefficiency, since surgery durations are stochastic. While most health care studies assume economically rational behavior of decision makers, experimental studies have shown that decision makers often do not act according to economic incentives. Based on insights from health care operations management, medical decision making, behavioral operations management, as well as empirical observations, we derive hypotheses that surgeons' behavior deviates from economically rational behavior. To investigate this, we undertake an experimental study where experienced surgeons are asked to plan surgeries with uncertain durations. We discover systematic deviations from optimal decision making and offer behavioral explanations for the observed biases. Our research provides new insights to tackle a major problem in hospitals, i.e. low operating room utilization going along with staff overtime.
A survey of current operational problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prince, W.R.; Nielsen, E.K.; McNair, H.D.
1989-11-01
This paper is prepared for use in the Working Group on Current Operational Problems (COPS) forums with the goal of focusing attention of the industry on problems faced by those who are involved in actual power system operation. The results of a survey on operational problems are presented in this paper. Statistical information compiled for various categories of operational problems is given with some general observations about the results. A rough comparison is made from the results of this survey and the first COPS problem list of 1976.
A novel interactive educational system in the operating room--the IE system.
Nakayama, Takayuki; Numao, Noboru; Yoshida, Soichiro; Ishioka, Junichiro; Matsuoka, Yoh; Saito, Kazutaka; Fujii, Yasuhisa; Kihara, Kazunori
2016-02-02
The shortage of surgeon is one of the serious problems in Japan. To solve the problem, various efforts have been undertaken to improve surgical education and training. However, appropriate teaching methods in the operating room have not been well established. The aim of this study is to assess the utility of a novel interactive educational (IE) system for surgical education on urologic surgeries in the operating room. A total of 20 Japanese medical students were educated on urologic surgery using the IE system in the operating room. The IE system consists of two parts. The first is three-dimensional (3D) magnified vision of the operative field using a 3D head-mounted display and a 3D endoscope. The second is interactive educative communication between medical students and surgeons using a small-sized wireless communication device. The satisfaction level with the IE system and the physical burden on medical students was examined via questionnaire. All students utilized the IE system in urologic surgery and responded to the survey. Most students were satisfied with the IE system. They also felt more welcomed by the surgeon when using the IE system than when not using it. No major unpleasant symptoms were observed but five students (25 %) experienced mild eye fatigue as a result of viewing the medical images. The IE system has the potential to motivate students to become interested in surgery and could be an efficient method of surgical education in the operating room.
Safe laser application requires more than laser safety
NASA Astrophysics Data System (ADS)
Frevel, A.; Steffensen, B.; Vassie, L.
1995-02-01
An overview is presented concerning aspects of laser safety in European industrial laser use. Surveys indicate that there is a large variation in the safety strategies amongst industrial laser users. Some key problem areas are highlighted. Emission of hazardous substances is a major problem for users of laser material processing systems where the majority of the particulate is of a sub-micrometre size, presenting a respiratory hazard. Studies show that in many cases emissions are not frequently monitored in factories and uncertainty exists over the hazards. Operators of laser machines do not receive adequate job training or safety training. The problem is compounded by a plethora of regulations and standards which are difficult to interpret and implement, and inspectors who are not conversant with the technology or the issues. A case is demonstrated for a more integrated approach to laser safety, taking into account the development of laser applications, organizational and personnel development, in addition to environmental and occupational health and safety aspects. It is necessary to achieve a harmonization between these elements in any organization involved in laser technology. This might be achieved through establishing technology transfer centres in laser technology.
Space Software for Automotive Design
NASA Technical Reports Server (NTRS)
1988-01-01
John Thousand of Wolverine Western Corp. put his aerospace group to work on an unfamiliar job, designing a brake drum using computer design techniques. Computer design involves creation of a mathematical model of a product and analyzing its effectiveness in simulated operation. Technique enables study of performance and structural behavior of a number of different designs before settling on a final configuration. Wolverine employees attacked a traditional brake drum problem, the sudden buildup of heat during fast and repeated braking. Part of brake drum not confined tends to change its shape under combination of heat, physical pressure and rotational forces, a condition known as bellmouthing. Since bellmouthing is a major factor in braking effectiveness, a solution of problem would be a major advance in automotive engineering. A former NASA employee, now a Wolverine employee, knew of a series of NASA computer programs ideally suited to confronting bellmouthing. Originally developed as aids to rocket engine nozzle design, it's capable of analyzing problems generated in a rocket engine or automotive brake drum by heat, expansion, pressure and rotational forces. Use of these computer programs led to new brake drum concept featuring a more durable axle, and heat transfer ribs, or fins, on hub of drum.
A system model to integrate the “Green Manufacturing” concept in Romanian manufacturing organisation
NASA Astrophysics Data System (ADS)
Tilină, D. I.; Zapciu, M.; Mohora, C.
2015-11-01
In Romania, the large majorities of the manufacturing companies consume natural resources and energy in an unsustainable manner. Over the years, the emissions of greenhouse gases have led not only to many environmental problems but also to important social and economic problems. A real solution to help the Romanian manufacturing companies to adapt to the new legislative requirements is the green manufacturing implementation. Considering the current situation, the purpose of this paper is to present a model that will integrate the green manufacturing concept at the organizational level based on the practices identified in the Romanian manufacturing companies at the operational level in the context of sustainable development.
Material handling systems for the fluidized-bed combustion boiler at Rivesville, West Virginia
NASA Technical Reports Server (NTRS)
Branam, J. G.; Rosborough, W. W.
1977-01-01
The 300,000 lbs/hr steam capacity multicell fluidized-bed boiler (MFB) utilizes complex material handling systems. The material handling systems can be divided into the following areas: (1) coal preparation; transfer and delivery, (2) limestone handling system, (3) fly-ash removal and (4) bed material handling system. Each of the above systems are described in detail and some of the potential problem areas are discussed. A major potential problem that exists is the coal drying system. The coal dryer is designed to use 600 F preheated combustion air as drying medium and the dryer effluent is designed to enter a hot electrostatic precipitator (730 F) after passage through a cyclone. Other problem areas to be discussed include the steam generator coal and limestone feed system which may have operating difficulties with wet coal and/or coal fines.
NASA'S Water Resources Element Within the Applied Sciences Program
NASA Technical Reports Server (NTRS)
Toll, David; Doorn, Bradley; Engman, Edwin
2011-01-01
The NASA Earth Systems Division has the primary responsibility for the Applied Science Program and the objective to accelerate the use of NASA science results in applications to help solve problems important to society and the economy. The primary goal of the NASA Applied Science Program is to improve future and current operational systems by infusing them with scientific knowledge of the Earth system gained through space-based observation, assimilation of new observations, and development and deployment of enabling technologies, systems, and capabilities. This paper discusses major problems facing water resources managers, including having timely and accurate data to drive their decision support tools. It then describes how NASA's science and space based satellites may be used to overcome this problem. Opportunities for the water resources community to participate in NASA's Water Resources Applications Program are described.
Depression and Disordered Eating in the Obese Person
Faulconbridge, Lucy F.; Bechtel, Colleen F.
2014-01-01
Three mental health problems commonly associated with obesity are major depression, binge eating disorder (BED), and Night Eating Syndrome (NES). Evidence from both cross-sectional and longitudinal studies support independent relationships between obesity and depression, and between obesity and binge eating. These problems are most prevalent in severely obese individuals (Class III obesity; a body mass index (BMI) of >40kgm2), many of whom seek bariatric surgery, and we briefly review whether the presence of pre-operative depression, BED or NES affects post-operative outcomes. Historically depressed individuals have been screened out of weight loss trials due to concerns of worsening mood with weight loss. Such practices have precluded the development of effective treatments for depressed, obese individuals, leaving large numbers of people without appropriate care. We present recent advances in this area, and attempt to answer whether depressed individuals can lose clinically significant amounts of weight, show improvements in mood, and adhere to the demands of a weight loss intervention. PMID:24678445
Potential of minicomputer/array-processor system for nonlinear finite-element analysis
NASA Technical Reports Server (NTRS)
Strohkorb, G. A.; Noor, A. K.
1983-01-01
The potential of using a minicomputer/array-processor system for the efficient solution of large-scale, nonlinear, finite-element problems is studied. A Prime 750 is used as the host computer, and a software simulator residing on the Prime is employed to assess the performance of the Floating Point Systems AP-120B array processor. Major hardware characteristics of the system such as virtual memory and parallel and pipeline processing are reviewed, and the interplay between various hardware components is examined. Effective use of the minicomputer/array-processor system for nonlinear analysis requires the following: (1) proper selection of the computational procedure and the capability to vectorize the numerical algorithms; (2) reduction of input-output operations; and (3) overlapping host and array-processor operations. A detailed discussion is given of techniques to accomplish each of these tasks. Two benchmark problems with 1715 and 3230 degrees of freedom, respectively, are selected to measure the anticipated gain in speed obtained by using the proposed algorithms on the array processor.
Tanks focus area multiyear program plan FY97-FY99
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-08-01
The U.S. Department of Energy (DOE) continues to face a major tank remediation problem with approximately 332 tanks storing over 378,000 ml of high-level waste (HLW) and transuranic (TRU) waste across the DOE complex. Most of the tanks have significantly exceeded their life spans. Approximately 90 tanks across the DOE complex are known or assumed to have leaked. Some of the tank contents are potentially explosive. These tanks must be remediated and made safe. How- ever, regulatory drivers are more ambitious than baseline technologies and budgets will support. Therefore, the Tanks Focus Area (TFA) began operation in October 1994. Themore » focus area manages, coordinates, and leverages technology development to provide integrated solutions to remediate problems that will accelerate safe and cost-effective cleanup and closure of DOE`s national tank system. The TFA is responsible for technology development to support DOE`s four major tank sites: Hanford Site (Washington), INEL (Idaho), Oak Ridge Reservation (ORR) (Tennessee), and Savannah River Site (SRS) (South Carolina). Its technical scope covers the major functions that comprise a complete tank remediation system: safety, characterization, retrieval, pretreatment, immobilization, and closure.« less
NASA Astrophysics Data System (ADS)
Roth, Wolff-Michael; Milkent, Marlene M.
This study was designed as a test for two neo-Piagetian theories. More specifically, this research examined the relationships between the development of proportional reasoning strategies and three cognitive variables from Pascual-Leone's and Case's neo-Piagetian theories. A priori hypotheses linked the number of problems students worked until they induced a proportional reasoning strategy to the variables of M-space, degree of field dependence, and short-term storage space. The subjects consisted of students enrolled in Physical Science I, a science course for nonscience majors at the University of Southern Mississippi. Of the 34 subjects in the study, 23 were classified as concrete operational on the basis of eight ratio tasks. Problems corresponding to five developmental levels of proportional reasoning (according to Piagetian and neo-Piagetian theory), were presented by a microcomputer to the 23 subjects who had been classified as concrete operational. After a maximum of 6 hours of treatment, 17 of the 23 subjects had induced ratio schemata at the upper formal level (IIIB), while the remaining subjects used lower formal level (IIIA) schemata. The data analyses showed that neither M-space and degree of field-dependence, either alone or in combination, nor short-term storage predicted the number of problems students need to do until they induce an appropriate problem-solving strategy. However, there were significant differences in the short-term storage space of those subjects who mastered ratio problems at the highest level and those who did not. Also, the subjects' degree of field-dependence was not a predictor of either the ability to transfer problem-solving strategies to a new setting or the reuse of inappropriate strategies. The results of this study also suggest that short-term storage space is a variable with high correlations to a number of aspects of learning such as transfer and choice of strategy after feedback.
Mitsuhashi, Kenji; Poudel, Joemini; Matthews, Thomas P.; Garcia-Uribe, Alejandro; Wang, Lihong V.; Anastasio, Mark A.
2017-01-01
Photoacoustic computed tomography (PACT) is an emerging imaging modality that exploits optical contrast and ultrasonic detection principles to form images of the photoacoustically induced initial pressure distribution within tissue. The PACT reconstruction problem corresponds to an inverse source problem in which the initial pressure distribution is recovered from measurements of the radiated wavefield. A major challenge in transcranial PACT brain imaging is compensation for aberrations in the measured data due to the presence of the skull. Ultrasonic waves undergo absorption, scattering and longitudinal-to-shear wave mode conversion as they propagate through the skull. To properly account for these effects, a wave-equation-based inversion method should be employed that can model the heterogeneous elastic properties of the skull. In this work, a forward model based on a finite-difference time-domain discretization of the three-dimensional elastic wave equation is established and a procedure for computing the corresponding adjoint of the forward operator is presented. Massively parallel implementations of these operators employing multiple graphics processing units (GPUs) are also developed. The developed numerical framework is validated and investigated in computer19 simulation and experimental phantom studies whose designs are motivated by transcranial PACT applications. PMID:29387291
Reducing environmental noise impacts: A USAREUR noise management program handbook
NASA Astrophysics Data System (ADS)
Feather, Timothy D.; Shekell, Ted K.
1991-06-01
Noise pollution is a major environmental problem faced by the U.S. Army in Europe. Noise-related complaints from German citizens can escalate into intense political issues in German communities. This in turn hampers efficient operation of military training and often times threatens the Army's mission. In order to remedy these problems, USAREUR has developed a noise management program. A successful noise management program will limit the impact of unavoidable noise on the populace. This report, a component of the noise management program, is a reference document for noise management planning. It contains guidelines and rules-of-thumb for noise management. This document contains procedures which operation and training level personnel can understand and apply in their day to day noise management planning. Noise mitigation tips are given. Basic technical information that will aid in understanding noise mitigation is provided along with noise management through land use planning. Noise management for specific components of the military community, (airfields, base operations, training areas, and housing and recreation areas) are addressed. The nature of noise generated, means of noise abatement at the source, path, and receiver (both physical and organizational/public relations methods), and a case study example are described.
Fire suppression in human-crew spacecraft
NASA Technical Reports Server (NTRS)
Friedman, Robert; Dietrich, Daniel L.
1991-01-01
Fire extinguishment agents range from water and foam in early-design spacecraft (Halon 1301 in the present Shuttle) to carbon dioxide proposed for the Space Station Freedom. The major challenge to spacecraft fire extinguishment design and operations is from the micro-gravity environment, which minimizes natural convection and profoundly influences combustion and extinguishing agent effectiveness, dispersal, and post-fire cleanup. Discussed here are extinguishment in microgravity, fire-suppression problems anticipated in future spacecraft, and research needs and opportunities.
A review of utility issues for the integration of wind electric generators
NASA Technical Reports Server (NTRS)
Reddoch, T. W.; Barnes, P. R.
1982-01-01
A review of issues and concerns of the electric utility industry for the integration of wind electric generation is offered. The issues have been categorized in three major areas: planning, operations, and dynamic interaction. Representative studies have been chosen for each area to illustrate problems and to alleviate some concerns. The emphasis of this paper is on individual large wind turbines (WTs) and WT arrays for deployment at the bulk level in a utility system.
Wang, Xin; Duan, Runyao
2017-11-03
We demonstrate the irreversibility of asymptotic entanglement manipulation under quantum operations that completely preserve the positivity of partial transpose (PPT), resolving a major open problem in quantum information theory. Our key tool is a new efficiently computable additive lower bound for the asymptotic relative entropy of entanglement with respect to PPT states, which can be used to evaluate the entanglement cost under local operations and classical communication (LOCC). We find that for any rank-two mixed state supporting on the 3⊗3 antisymmetric subspace, the amount of distillable entanglement by PPT operations is strictly smaller than one entanglement bit (ebit) while its entanglement cost under PPT operations is exactly one ebit. As a by-product, we find that for this class of states, both the Rains's bound and its regularization are strictly less than the asymptotic relative entropy of entanglement. So, in general, there is no unique entanglement measure for the manipulation of entanglement by PPT operations. We further show a computable sufficient condition for the irreversibility of entanglement distillation by LOCC (or PPT) operations.
Methods and circuitry for reconfigurable SEU/SET tolerance
NASA Technical Reports Server (NTRS)
Shuler, Jr., Robert L. (Inventor)
2010-01-01
A device is disclosed in one embodiment that has multiple identical sets of programmable functional elements, programmable routing resources, and majority voters that correct errors. The voters accept a mode input for a redundancy mode and a split mode. In the redundancy mode, the programmable functional elements are identical and are programmed identically so the voters produce an output corresponding to the majority of inputs that agree. In a split mode, each voter selects a particular programmable functional element output as the output of the voter. Therefore, in the split mode, the programmable functional elements can perform different functions, operate independently, and/or be connected together to process different parts of the same problem.
Using full-mission simulation for human factors research in air transport operations
NASA Technical Reports Server (NTRS)
Orlady, Harry W.; Hennessy, Robert W.; Obermayer, Richard; Vreuls, Donald; Murphy, Miles R.
1988-01-01
This study examined state-of-the-art mission oriented simulation and its use in human factors research. Guidelines were developed for doing full-mission human factors research on crew member behavior during simulated air transport operations. The existing literature was reviewed. However, interviews with experienced investigators provided the most useful information. The fundamental scientific and practical issues of behavioral research in a simulation environment are discussed. Guidelines are presented for planning, scenario development, and the execution of behavioral research using full-mission simulation in the context of air transport flight operations . Research is recommended to enhance the validity and productivity of full-mission research by: (1) validating the need for high-fidelity simulation of all major elements in the operational environment, (2) improving methods for conducting full-mission research, and (3) examining part-task research on specific problems through the use of vehicles which contain higher levels of abstraction (and lower fidelity) of the operational environment.
The experience in operation and improving the Orlan-type space suits.
Abramov, I P
1995-07-01
Nowadays significant experience has been gained in Russia concerning extravehicular activity (EVA) with cosmonauts wearing a semi-rigid space suit of the "Orlan" type. The conditions for the cosmonauts' vital activities, the operational and ergonomic features of the space suit and its reliability are the most critical factors defining the efficiency of the scheduled operation to be performed by the astronaut and his safety. As the missions performed by the cosmonauts during EVA become more and more elaborate, the requirements for EVA space suits and their systems become more and more demanding, resulting in their consistent advancement. This paper provides certain results of the space suit's operation and analysis of its major problems as applied to the Salyut and MIR orbiting stations. The modification steps of the space suit in the course of operation (Orlan-D, Orlan-DM, Orlan-DMA) and its specific features are presented. The concept of the suited cosmonauts' safety is described as well as trends for future space suit improvements.
A touch probe method of operating an implantable RFID tag for orthopedic implant identification.
Liu, Xiaoyu; Berger, J Lee; Ogirala, Ajay; Mickle, Marlin H
2013-06-01
The major problem in operating an implantable radio-frequency identification (RFID) tag embedded on an orthopedic implant is low efficiency because of metallic interference. To improve the efficiency, this paper proposes a method of operating an implantable passive RFID tag using a touch probe at 13.56 MHz. This technology relies on the electric field interaction between two pairs of electrodes, one being a part of the touch probe placed on the surface of tissue and the other being a part of the tag installed under the tissue. Compared with using a conventional RFID antenna such as a loop antenna, this method has a better performance in the near field operation range to reduce interference with the orthopedic implant. Properly matching the touch probe and the tag to the tissue and the implant reduces signal attenuation and increases the overall system efficiency. The experiments have shown that this method has a great performance in the near field transcutaneous operation and can be used for orthopedic implant identification.
The determination of effective injury controls for metal-cutting lathe operators.
Etherton, J R; Trump, T R; Jensen, R C
1981-01-01
Operators of metal-working lathes are one of the largest manufacturing machine worker populations in the United States. Machines (other than vehicular) account for over 10% of occupational injuries each year. An estimated 3,400 operators of metal-working lathes suffer lost-time injuries annually in the United States. Some of these are fatal. Therefore an investigation was undertaken to determine methods for reducing injuries to lathe operators. Three methods were used: (i) review of injury reports, (ii) human factors analysis, and (iii) fault-tree procedures. The investigation followed the man-machine systems approach of looking for injury-producing dysfunctions between the lathe and the lathe operator. The major sources of injury were found to be chips and workholding devices. Secondary tasks were found to be more hazardous than is generally recognized. The use of three methods for approaching the problem was found to be useful in that injury controls were identified which are likely to be adopted because of their potential for improving safety without adversely affecting productivity.
Dengue and US military operations from the Spanish-American War through today.
Gibbons, Robert V; Streitz, Matthew; Babina, Tatyana; Fried, Jessica R
2012-04-01
Dengue is a major cause of illness among travelers and a threat to military troops operating in areas to which it is endemic. Before and during World War II, dengue frequently occurred in US military personnel in Asia and the South Pacific. From the 1960s into the 1990s, dengue often occurred in US troops in Vietnam, the Philippines, Somalia, and Haiti. We found attack rates as high as 80% and periods of convalescence up to 3-1/2 weeks beyond the acute illness. The increase in dengue throughout the world suggests that it will remain a problem for military personnel until an effective vaccine is licensed.
Optics and materials research for controlled radiant energy transfer in buildings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goldner, R.B.
1983-11-01
The overall objective of the Tufts research program was to identify and attempt to solve some of the key materials problems associated with practical approaches for achieving controlled radiant energy transfer (CRET) through building windows and envelopes, so as to decrease heating and cooling loads in buildings. Major accomplishments included: the identification of electrochromic (EC)-based structures as the preferred structures for achieving CRET the identification of modulated reflectivity as the preferred mode of operation for EC-based structures demonstration of the feasibility of operating EC-materials in a modulated R(lambda) mode and demonstration of the applicability of free electron model to coloredmore » polycrystalline WO3 films.« less
Saudi English-Major Undergraduates' Academic Writing Problems: A Taif University Perspective
ERIC Educational Resources Information Center
Al-Khairy, Mohamed Ali
2013-01-01
This study attempted to investigate Saudi English-major undergraduates studying at Taif University to identify a) the types of academic writing Saudi English-major undergraduates carry out at English departments, b) Saudi English-major undergraduates' writing problems, c) the reasons behind Saudi English-major undergraduates' writing problems and…
Zanotti, G; Ligabue, G; Gobba, F
2015-09-01
Using a specific questionnaire, we examined subjective symptoms in a group of 17 physicians (9 males and 8 females, mean age 32.9 ± 3.71), attending a Postgraduate Medical School in Radiology and engaged in MRI for less than 1 year. Sixteen subjects (94%) reported the presence of at least one of the investigated symptoms during the period of MRI activity. The main symptoms were: unusual drowsiness/tiredness (88%), concentration problems (82%), headaches (76%), sleep disorders (47%), nausea (47%), illusion of movement (47%) and dizziness/vertigo (35%); the former two were subjectively related to MRI by the majority of the operators. These symptoms appeared (or worsened) in more than 15 min and, in the vast majority disappeared 30 min, or more, after the end of exposure. In 13 subjects (81%), the symptom (or some symptoms) appeared at least weekly. In this small group of health care workers recently exposed to MRI, the prevalence of subjective symptoms was higher than reported in other similar studies but, notably, the majority of subjects (77%) reported a regression within 4-8 weeks, suggesting some form of adaptation.
Hu, Yue-Yung; Arriaga, Alexander F.; Roth, Emilie M.; Peyre, Sarah E.; Corso, Katherine A.; Swanson, Richard S.; Osteen, Robert T.; Schmitt, Pamela; Bader, Angela M.; Zinner, Michael J.; Greenberg, Caprice C.
2012-01-01
Objective To understand the etiology and resolution of unanticipated events in the operating room (OR). Background The majority of surgical adverse events occur intra-operatively. The OR represents a complex, high-risk system. The influence of different human, team, and organizational/environmental factors on safety and performance is unknown. Methods We video-recorded and transcribed 10 high-acuity operations, representing 43.7 hours of patient care. Deviations, defined as delays and/or episodes of decreased patient safety, were identified by majority consensus of a multidisciplinary team. Factors that contributed to each event and/or mitigated its impact were determined and attributed to the patient, providers, or environment/organization. Results Thirty-three deviations (10 delays, 17 safety compromises, 6 both) occurred – with a mean of one every 79.4 minutes. These deviations were multifactorial (mean 3.1 factors). Problems with communication and organizational structure appeared repeatedly at the root of both types of deviations. Delays tended to be resolved with vigilance, communication, coordination, and cooperation, while mediation of safety compromises was most frequently accomplished with vigilance, leadership, communication, and/or coordination. The organization/environment was not found to play a direct role in compensation. Conclusions Unanticipated events are common in the OR. Deviations result from poor organizational/environmental design and suboptimal team dynamics, with caregivers compensating to avoid patient harm. While recognized in other high risk domains, such human resilience has not yet been described in surgery and has major implications for the design of safety interventions. PMID:22750753
NASA Technical Reports Server (NTRS)
Murray, John J.; Hudnall, L. A.; Matus, A.; Krueger, A. J.; Trepte, C. r.
2010-01-01
The Aleutian Islands of Alaska are home to a number of major volcanoes which periodically present a significant hazard to aviation. During summer of 2008, the Okmok and Kasatochi volcanoes experienced moderate eruptive events. These were followed a dramatic, major eruption of Mount Redoubt in late March 2009. The Redoubt case is extensively covered in this paper. Volcanic ash and SO2 from each of these eruptions dispersed throughout the atmosphere. This created the potential for major problems for air traffic near the ash dispersions and at significant distances downwind. The NASA Applied Sciences Weather Program implements a wide variety of research projects to develop volcanic ash detection, characterization and tracking applications for NASA Earth Observing System and NOAA GOES and POES satellites. Chemistry applications using NASA AURA satellite Ozone Monitoring System (OMI) retrievals produced SO2 measurements to trace the dispersion of volcanic aerosol. This work was complimented by advanced multi-channel imager applications for the discrimination and height assignment of volcanic ash using NASA MODIS and NOAA GOES and POES imager data. Instruments similar to MODIS and OMI are scheduled for operational deployment on NPOESS. In addition, the NASA Calipso satellite provided highly accurate measurements of aerosol height and dispersion for the calibration and validation of these algorithms and for corroborative research studies. All of this work shortens the lead time for transition to operations and ensures that research satellite data and applications are operationally relevant and utilized quickly after the deployment of operational satellite systems. Introduction
Composite material impregnation unit
NASA Technical Reports Server (NTRS)
Wilkinson, S. P.; Marchello, J. M.; Johnston, N. J.
1993-01-01
This memorandum presents an introduction to the NASA multi-purpose prepregging unit which is now installed and fully operational at the Langley Research Center in the Polymeric Materials Branch. A description of the various impregnation methods that are available to the prepregger are presented. Machine operating details and protocol are provided for its various modes of operation. These include, where appropriate, the related equations for predicting the desired prepreg specifications. Also, as the prepregger is modular in its construction, each individual section is described and discussed. Safety concerns are an important factor and a chapter has been included that highlights the major safety features. Initial experiences and observations for fiber impregnation are described. These first observations have given great insight into the areas of future work that need to be addressed. Future memorandums will focus on these individual processes and their related problems.
NASA Technical Reports Server (NTRS)
Maxwell, Theresa G.; McNair, Ann R. (Technical Monitor)
2002-01-01
The planning processes for the International Space Station (ISS) Program are quite complex. Detailed mission planning for ISS on-orbit operations is a distributed function. Pieces of the on-orbit plan are developed by multiple planning organizations, located around the world, based on their respective expertise and responsibilities. The "pieces" are then integrated to yield the final detailed plan that will be executed onboard the ISS. Previous space programs have not distributed the planning and scheduling functions to this extent. Major ISS planning organizations are currently located in the United States (at both the NASA Johnson Space Center (JSC) and NASA Marshall Space Flight Center (MSFC)), in Russia, in Europe, and in Japan. Software systems have been developed by each of these planning organizations to support their assigned planning and scheduling functions. Although there is some cooperative development and sharing of key software components, each planning system has been tailored to meet the unique requirements and operational environment of the facility in which it operates. However, all the systems must operate in a coordinated fashion in order to effectively and efficiently produce a single integrated plan of ISS operations, in accordance with the established planning processes. This paper addresses lessons learned during the development of these multiple distributed planning systems, from the perspective of the developer of one of the software systems. The lessons focus on the coordination required to allow the multiple systems to operate together, rather than on the problems associated with the development of any particular system. Included in the paper is a discussion of typical problems faced during the development and coordination process, such as incompatible development schedules, difficulties in defining system interfaces, technical coordination and funding for shared tools, continually evolving planning concepts/requirements, programmatic and budget issues, and external influences. Techniques that mitigated some of these problems will also be addressed, along with recommendations for any future programs involving the development of multiple planning and scheduling systems. Many of these lessons learned are not unique to the area of planning and scheduling systems, so may be applied to other distributed ground systems that must operate in concert to successfully support space mission operations.
NASA Technical Reports Server (NTRS)
Maxwell, Theresa G.
2002-01-01
The planning processes for the International Space Station (ISS) Program are quite complex. Detailed mission planning for ISS on-orbit operations is a distributed function. Pieces of the on-orbit plan are developed by multiple planning organizations, located around the world, based on their respective expertise and responsibilities. The pieces are then integrated to yield the final detailed plan that will be executed onboard the ISS. Previous space programs have not distributed the planning and scheduling functions to this extent. Major ISS planning organizations are currently located in the United States (at both the NASA Johnson Space Center (JSC) and NASA Marshall Space Flight Center (MSFC)), in Russia, in Europe, and in Japan. Software systems have been developed by each of these planning organizations to support their assigned planning and scheduling functions. Although there is some cooperative development and sharing of key software components, each planning system has been tailored to meet the unique requirements and operational environment of the facility in which it operates. However, all the systems must operate in a coordinated fashion in order to effectively and efficiently produce a single integrated plan of ISS operations, in accordance with the established planning processes. This paper addresses lessons learned during the development of these multiple distributed planning systems, from the perspective of the developer of one of the software systems. The lessons focus on the coordination required to allow the multiple systems to operate together, rather than on the problems associated with the development of any particular system. Included in the paper is a discussion of typical problems faced during the development and coordination process, such as incompatible development schedules, difficulties in defining system interfaces, technical coordination and funding for shared tools, continually evolving planning concepts/requirements, programmatic and budget issues, and external influences. Techniques that mitigated some of these problems will also be addressed, along with recommendations for any future programs involving the development of multiple planning and scheduling systems. Many of these lessons learned are not unique to the area of planning and scheduling systems, so may be applied to other distributed ground systems that must operate in concert to successfully support space mission operations.
Simultaneous personnel and vehicle shift scheduling in the waste management sector.
Ghiani, Gianpaolo; Guerriero, Emanuela; Manni, Andrea; Manni, Emanuele; Potenza, Agostino
2013-07-01
Urban waste management is becoming an increasingly complex task, absorbing a huge amount of resources, and having a major environmental impact. The design of a waste management system consists in various activities, and one of these is related to the definition of shift schedules for both personnel and vehicles. This activity has a great incidence on the tactical and operational cost for companies. In this paper, we propose an integer programming model to find an optimal solution to the integrated problem. The aim is to determine optimal schedules at minimum cost. Moreover, we design a fast and effective heuristic to face large-size problems. Both approaches are tested on data from a real-world case in Southern Italy and compared to the current practice utilized by the company managing the service, showing that simultaneously solving these problems can lead to significant monetary savings. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA's Applied Sciences for Water Resources
NASA Technical Reports Server (NTRS)
Doorn, Bradley; Toll, David; Engman, Ted
2011-01-01
The Earth Systems Division within NASA has the primary responsibility for the Earth Science Applied Science Program and the objective to accelerate the use of NASA science results in applications to help solve problems important to society and the economy. The primary goal of the Earth Science Applied Science Program is to improve future and current operational systems by infusing them with scientific knowledge of the Earth system gained through space-based observation, assimilation of new observations, and development and deployment of enabling technologies, systems, and capabilities. This paper discusses one of the major problems facing water resources managers, that of having timely and accurate data to drive their decision support tools. It then describes how NASA?s science and space based satellites may be used to overcome this problem. Opportunities for the water resources community to participate in NASA?s Water Resources Applications Program are described.
Hasegawa, Arifumi; Tanigawa, Koichi; Ohtsuru, Akira; Yabe, Hirooki; Maeda, Masaharu; Shigemura, Jun; Ohira, Tetsuya; Tominaga, Takako; Akashi, Makoto; Hirohashi, Nobuyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Shibuya, Kenji; Yamashita, Shunichi; Chhem, Rethy K
2015-08-01
437 nuclear power plants are in operation at present around the world to meet increasing energy demands. Unfortunately, five major nuclear accidents have occurred in the past--ie, at Kyshtym (Russia [then USSR], 1957), Windscale Piles (UK, 1957), Three Mile Island (USA, 1979), Chernobyl (Ukraine [then USSR], 1986), and Fukushima (Japan, 2011). The effects of these accidents on individuals and societies are diverse and enduring. Accumulated evidence about radiation health effects on atomic bomb survivors and other radiation-exposed people has formed the basis for national and international regulations about radiation protection. However, past experiences suggest that common issues were not necessarily physical health problems directly attributable to radiation exposure, but rather psychological and social effects. Additionally, evacuation and long-term displacement created severe health-care problems for the most vulnerable people, such as hospital inpatients and elderly people. Copyright © 2015 Elsevier Ltd. All rights reserved.
Adapting to regional enforcement: fishing down the governance index.
Osterblom, Henrik; Sumaila, U Rashid; Bodin, Orjan; Hentati Sundberg, Jonas; Press, Anthony J
2010-09-17
Illegal, Unreported and Unregulated (IUU) fishing is a problem for marine resource managers, leading to depletion of fish stocks and negative impacts on marine ecosystems. These problems are particularly evident in regions with weak governance. Countries responsible for sustainable natural resource management in the Southern Ocean have actively worked to reduce IUU fishing in the region over a period of 15 years, leading to a sequence of three distinct peaks of IUU fishing. We reviewed existing public records relating to IUU fishing in the Southern Ocean between 1995-2009 and related this information to the governance capacity of flag states responsible for IUU vessels. IUU operators used a number of methods to adapt to enforcement actions, resulting in reduced risks of detection, apprehension and sanctioning. They changed fishing locations, vessel names and flag states, and ports for offloading IUU catches. There was a significant decrease in the proportion of IUU vessels flagged to CCAMLR countries, and a significant decrease in the average governance index of flag states. Despite a decreasing trend of IUU fishing, further actions are hampered by the regional scope of CCAMLR and the governance capacity of responsible states. This is the first study of long-term change in the modus operandi of IUU fishing operators, illustrating that IUU operators can adapt to enforcement actions and that such dynamics may lead to new problems elsewhere, where countries have a limited capacity. This outsourcing of problems may have similarities to natural resource extraction in other sectors and in other regions. IUU fishing is the result of a number of factors, and effectively addressing this major challenge to sustainable marine resource extraction will likely require a stronger focus on governance. Highly mobile resource extractors with substantial funds are able to adapt to changing regulations by exploiting countries and regions with limited capacity.
2010-08-02
2000). The relationship between anxiety disorders and alcohol use disorder: A review of major perspectives and findings. Clin Psychol Rev, 20, 149...treatment programs. While at times there have been measureable decreases in heavy alcohol consumption over the past two and a half decades, the most...problems among returning war veterans, or causing some service members to begin abusing alcohol or drugs upon the difficult transition home. A 2004
Anaerobic digestion foaming causes--a review.
Ganidi, Nafsika; Tyrrel, Sean; Cartmell, Elise
2009-12-01
Anaerobic digestion foaming has been encountered in several sewage treatment plants in the UK. Foaming has raised major concerns for the water companies due to significant impacts on process efficiency and operational costs. Several foaming causes have been identified over the past few years by researchers. However, the supporting experimental information is limited and in some cases absent. The present report aims to provide a detailed review of the current anaerobic digestion foaming problem and to identify gaps in knowledge regarding the theory of foam formation in anaerobic digesters.
[Questions concerning humanitarian action].
Simonnot, C
2002-01-01
Although development of humanitarian action is rooted historical events, the dynamics behind today's international relief organizations can only be understood within the context of the modern world. Relief organizations are currently confronted with major challenges and paradoxes. The challenges include the need to enhance professionalization and standardization of assistance operations and exposure to greater risks. The paradoxes involve the need to implement complex, highly publicized programs in a simplistic manner and problems involved in managing the complex relationship between relief workers and victims, tainted with the almighty powers of the actors.
Development of quantitative risk acceptance criteria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griesmeyer, J. M.; Okrent, D.
Some of the major considerations for effective management of risk are discussed, with particular emphasis on risks due to nuclear power plant operations. Although there are impacts associated with the rest of the fuel cycle, they are not addressed here. Several previously published proposals for quantitative risk criteria are reviewed. They range from a simple acceptance criterion on individual risk of death to a quantitative risk management framework. The final section discussed some of the problems in the establishment of a framework for the quantitative management of risk.
Development of the ageing management database of PUSPATI TRIGA reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramli, Nurhayati, E-mail: nurhayati@nm.gov.my; Tom, Phongsakorn Prak; Husain, Nurfazila
Since its first criticality in 1982, PUSPATI TRIGA Reactor (RTP) has been operated for more than 30 years. As RTP become older, ageing problems have been seen to be the prominent issues. In addressing the ageing issues, an Ageing Management (AgeM) database for managing related ageing matters was systematically developed. This paper presents the development of AgeM database taking into account all RTP major Systems, Structures and Components (SSCs) and ageing mechanism of these SSCs through the system surveillance program.
Interfacing laboratory instruments to multiuser, virtual memory computers
NASA Technical Reports Server (NTRS)
Generazio, Edward R.; Stang, David B.; Roth, Don J.
1989-01-01
Incentives, problems and solutions associated with interfacing laboratory equipment with multiuser, virtual memory computers are presented. The major difficulty concerns how to utilize these computers effectively in a medium sized research group. This entails optimization of hardware interconnections and software to facilitate multiple instrument control, data acquisition and processing. The architecture of the system that was devised, and associated programming and subroutines are described. An example program involving computer controlled hardware for ultrasonic scan imaging is provided to illustrate the operational features.
Laparoscopic repair of parastomal hernia
Yang, Xuefei; He, Kai; Hua, Rong; Shen, Qiwei
2017-01-01
Parastomal hernia is one of the most common long-term complications after abdominal ostomy. Surgical treatment for parastomal hernia is the only cure but a fairly difficult field because of the problems of infection, effects, complications and recurrence. Laparoscopic repair operations are good choices for Parastomal hernia because of their mini-invasive nature and confirmed effects. There are several major laparoscopic procedures for parastomal hernioplasty. The indications, technical details and complications of them will be introduced and discussed in this article. PMID:28251124
Improving patient care in cardiac surgery using Toyota production system based methodology.
Culig, Michael H; Kunkle, Richard F; Frndak, Diane C; Grunden, Naida; Maher, Thomas D; Magovern, George J
2011-02-01
A new cardiac surgery program was developed in a community hospital setting using the operational excellence (OE) method, which is based on the principles of the Toyota production system. The initial results of the first 409 heart operations, performed over the 28 months between March 1, 2008, and June 30, 2010, are presented. Operational excellence methodology was taught to the cardiac surgery team. Coaching started 2 months before the opening of the program and continued for 24 months. Of the 409 cases presented, 253 were isolated coronary artery bypass graft operations. One operative death occurred. According to the database maintained by The Society of Thoracic Surgeons, the risk-adjusted operative mortality rate was 61% lower than the regional rate. Likewise, the risk-adjusted rate of major complications was 57% lower than The Society of Thoracic Surgeons regional rate. Daily solution to determine cause was attempted on 923 distinct perioperative problems by all team members. Using the cost of complications as described by Speir and coworkers, avoiding predicted complications resulted in a savings of at least $884,900 as compared with the regional average. By the systematic use of a real time, highly formatted problem-solving methodology, processes of care improved daily. Using carefully disciplined teamwork, reliable implementation of evidence-based protocols was realized by empowering the front line to make improvements. Low rates of complications were observed, and a cost savings of $3,497 per each case of isolated coronary artery bypass graft was realized. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
A System for Fault Management for NASA's Deep Space Habitat
NASA Technical Reports Server (NTRS)
Colombano, Silvano P.; Spirkovska, Liljana; Aaseng, Gordon B.; Mccann, Robert S.; Baskaran, Vijayakumar; Ossenfort, John P.; Smith, Irene Skupniewicz; Iverson, David L.; Schwabacher, Mark A.
2013-01-01
NASA's exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and/or asteroids. Communication latencies with ground control of as long as 20+ minutes make it imperative that DSH operations be highly autonomous, as any telemetry-based detection of a systems problem on Earth could well occur too late to assist the crew with the problem. A DSH-based development program has been initiated to develop and test the automation technologies necessary to support highly autonomous DSH operations. One such technology is a fault management tool to support performance monitoring of vehicle systems operations and to assist with real-time decision making in connection with operational anomalies and failures. Toward that end, we are developing Advanced Caution and Warning System (ACAWS), a tool that combines dynamic and interactive graphical representations of spacecraft systems, systems modeling, automated diagnostic analysis and root cause identification, system and mission impact assessment, and mitigation procedure identification to help spacecraft operators (both flight controllers and crew) understand and respond to anomalies more effectively. In this paper, we describe four major architecture elements of ACAWS: Anomaly Detection, Fault Isolation, System Effects Analysis, and Graphic User Interface (GUI), and how these elements work in concert with each other and with other tools to provide fault management support to both the controllers and crew. We then describe recent evaluations and tests of ACAWS on the DSH testbed. The results of these tests support the feasibility and strength of our approach to failure management automation and enhanced operational autonomy.
A System for Fault Management and Fault Consequences Analysis for NASA's Deep Space Habitat
NASA Technical Reports Server (NTRS)
Colombano, Silvano; Spirkovska, Liljana; Baskaran, Vijaykumar; Aaseng, Gordon; McCann, Robert S.; Ossenfort, John; Smith, Irene; Iverson, David L.; Schwabacher, Mark
2013-01-01
NASA's exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and/or asteroids. Communication latencies with ground control of as long as 20+ minutes make it imperative that DSH operations be highly autonomous, as any telemetry-based detection of a systems problem on Earth could well occur too late to assist the crew with the problem. A DSH-based development program has been initiated to develop and test the automation technologies necessary to support highly autonomous DSH operations. One such technology is a fault management tool to support performance monitoring of vehicle systems operations and to assist with real-time decision making in connection with operational anomalies and failures. Toward that end, we are developing Advanced Caution and Warning System (ACAWS), a tool that combines dynamic and interactive graphical representations of spacecraft systems, systems modeling, automated diagnostic analysis and root cause identification, system and mission impact assessment, and mitigation procedure identification to help spacecraft operators (both flight controllers and crew) understand and respond to anomalies more effectively. In this paper, we describe four major architecture elements of ACAWS: Anomaly Detection, Fault Isolation, System Effects Analysis, and Graphic User Interface (GUI), and how these elements work in concert with each other and with other tools to provide fault management support to both the controllers and crew. We then describe recent evaluations and tests of ACAWS on the DSH testbed. The results of these tests support the feasibility and strength of our approach to failure management automation and enhanced operational autonomy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tahvili, Sahar; Österberg, Jonas; Silvestrov, Sergei
One of the most important factors in the operations of many cooperations today is to maximize profit and one important tool to that effect is the optimization of maintenance activities. Maintenance activities is at the largest level divided into two major areas, corrective maintenance (CM) and preventive maintenance (PM). When optimizing maintenance activities, by a maintenance plan or policy, we seek to find the best activities to perform at each point in time, be it PM or CM. We explore the use of stochastic simulation, genetic algorithms and other tools for solving complex maintenance planning optimization problems in terms ofmore » a suggested framework model based on discrete event simulation.« less
[Acute traumatic and especially neglected traumatic hip dislocations are very rare in children].
Fernandez, F F; Wirth, T; Eberhardt, O
2012-09-01
We report about the first hip arthroscopies of extracapsular neglected hip dislocations with concomitant injuries in two children (2 and 4 years old). The major problem of traumatic hip dislocation is avascular necrosis. Further problems are possible concomitant injuries. It is important not to cause further damage by therapeutic procedures. In a 4-year-old child the hip could be reduced under visualization and in a 2-year-old child with epiphyseal fracture the extent of the operation could be reduced. In both children large avulsion injuries of the ligamentum capitis femoris could be resected via hip arthroscopy. Hip arthroscopy can reduce surgical morbidity considerably and can possibly contribute to prevention of the feared avascular necrosis of the femoral head.
NASA Astrophysics Data System (ADS)
Huber, Robert; Beranzoli, Laura; Fiebig, Markus; Gilbert, Olivier; Laj, Paolo; Mazzola, Mauro; Paris, Jean-Daniel; Pedersen, Helle; Stocker, Markus; Vitale, Vito; Waldmann, Christoph
2017-04-01
European Environmental Research Infrastructures (RI) frequently comprise in situ observatories from large-scale networks of platforms or sites to local networks of various sensors. Network operation is usually a cumbersome aspect of these RIs facing specific technological problems related to operations in remote areas, maintenance of the network, transmission of observation values, etc.. Robust inter-connection within and across these networks is still at infancy level and the burden increases with remoteness of the station, harshness of environmental conditions, and unavailability of classic communication systems, which is a common feature here. Despite existing RIs having developed ad-hoc solutions to overcome specific problems and innovative technologies becoming available, no common approach yet exists. Within the European project ENVRIplus, a dedicated work package aims to stimulate common network operation technologies and approaches in terms of power supply and storage, robustness, and data transmission. Major objectives of this task are to review existing technologies and RI requirements, propose innovative solutions and evaluate the standardization potential prior to wider deployment across networks. Focus areas within these efforts are: improving energy production and storage units, testing robustness of RI equipment towards extreme conditions as well as methodologies for robust data transmission. We will introduce current project activities which are coordinated at various levels including the engineering as well as the data management perspective, and explain how environmental RIs can benefit from the developments.
NASA Astrophysics Data System (ADS)
Abderrahim, Iheb
Wind power generation has grown strongly in the last decade. This results in the development of Wind Energy Conversion System WECS at the levels of modeling and electrical control. Modern WECS operate at varying wind speeds and are equipped with synchronous and asynchronous generators. Among these generators, the Doubly-Fed Induction Generator (DFIG) offers several advantages and capabilities of active and reactive power in four quadrants. WECS based DFIG also causes less conversion costs and minimum energy losses compared with a WECS based on a synchronous generator powered entirely by full scale of power converters. The connection of such a system to the electrical distribution network involves bidirectional operation of networks. This is clearly established in sub and super synchronous operating modes of DFIG. The grid provides the active power to the rotor of DFIG in sub synchronous operating mode and receives the active power of the rotor in super synchronous operating mode of DFIG. Energy quality is thus of major importance during the integration of wind power to the grid. Poor wave quality can affect network stability and could even cause major problems and consequences. This is even more critical where non-linear loads such as the switching power supplies and variable speed drives, are connected to the grid. The idea of this research work is how to mitigate the problems associated with the wave quality while ensuring better implementation of DFIG so that the whole of WECS remains insensitive to external disturbances and parametric variations. The Grid Side Converter (GSC) must be able to compensate harmonics, current unbalance and reactive power injected by a nonlinear three-phase unbalanced load connected to the grid. In addition to these innovative features to improve the conditions of operation of the grid, it provides also the power flow during different modes of operation of the DFIG. It is considered a simple, efficient and cost competitive solution by saving the use of other power equipment. At the same time, the energy efficiency of wind power conversion chain should be improved by extracting the MPPT. Searching allows us to select vector control and control in synchronous reference to achieve these objectives. WECS based DFIG is simulated in MATLAB SIMULINK in the presence of a non-linear balanced and unbalanced three-phase load.
A pedestrian approach to the measurement problem in quantum mechanics
NASA Astrophysics Data System (ADS)
Boughn, Stephen; Reginatto, Marcel
2013-09-01
The quantum theory of measurement has been a matter of debate for over eighty years. Most of the discussion has focused on theoretical issues with the consequence that other aspects (such as the operational prescriptions that are an integral part of experimental physics) have been largely ignored. This has undoubtedly exacerbated attempts to find a solution to the "measurement problem". How the measurement problem is defined depends to some extent on how the theoretical concepts introduced by the theory are interpreted. In this paper, we fully embrace the minimalist statistical (ensemble) interpretation of quantum mechanics espoused by Einstein, Ballentine, and others. According to this interpretation, the quantum state description applies only to a statistical ensemble of similarly prepared systems rather than representing an individual system. Thus, the statistical interpretation obviates the need to entertain reduction of the state vector, one of the primary dilemmas of the measurement problem. The other major aspect of the measurement problem, the necessity of describing measurements in terms of classical concepts that lay outside of quantum theory, remains. A consistent formalism for interacting quantum and classical systems, like the one based on ensembles on configuration space that we refer to in this paper, might seem to eliminate this facet of the measurement problem; however, we argue that the ultimate interface with experiments is described by operational prescriptions and not in terms of the concepts of classical theory. There is no doubt that attempts to address the measurement problem have yielded important advances in fundamental physics; however, it is also very clear that the measurement problem is still far from being resolved. The pedestrian approach presented here suggests that this state of affairs is in part the result of searching for a theoretical/mathematical solution to what is fundamentally an experimental/observational question. It suggests also that the measurement problem is, in some sense, ill-posed and might never be resolved. This point of view is tenable so long as one is willing to view physical theories as providing models of nature rather than complete descriptions of reality. Among other things, these considerations lead us to suggest that the Copenhagen interpretation's insistence on the classicality of the measurement apparatus should be replaced by the requirement that a measurement, which is specified operationally, should simply be of sufficient precision.
Nonexpansiveness of a linearized augmented Lagrangian operator for hierarchical convex optimization
NASA Astrophysics Data System (ADS)
Yamagishi, Masao; Yamada, Isao
2017-04-01
Hierarchical convex optimization concerns two-stage optimization problems: the first stage problem is a convex optimization; the second stage problem is the minimization of a convex function over the solution set of the first stage problem. For the hierarchical convex optimization, the hybrid steepest descent method (HSDM) can be applied, where the solution set of the first stage problem must be expressed as the fixed point set of a certain nonexpansive operator. In this paper, we propose a nonexpansive operator that yields a computationally efficient update when it is plugged into the HSDM. The proposed operator is inspired by the update of the linearized augmented Lagrangian method. It is applicable to characterize the solution set of recent sophisticated convex optimization problems found in the context of inverse problems, where the sum of multiple proximable convex functions involving linear operators must be minimized to incorporate preferable properties into the minimizers. For such a problem formulation, there has not yet been reported any nonexpansive operator that yields an update free from the inversions of linear operators in cases where it is utilized in the HSDM. Unlike previously known nonexpansive operators, the proposed operator yields an inversion-free update in such cases. As an application of the proposed operator plugged into the HSDM, we also present, in the context of the so-called superiorization, an algorithmic solution to a convex optimization problem over the generalized convex feasible set where the intersection of the hard constraints is not necessarily simple.
NASA's Biomedical Research Program
NASA Technical Reports Server (NTRS)
Ahn, Chung-Hae
1981-01-01
The biomedical research program has been established to investigate the major physiological and psychological problems encountered by man when he undertakes spaceflight. The program seeks to obtain a better definition of each problem, an understanding of its underlying mechanism, and ultimately a means of prevention. In pursuing these goals the program also includes a major effort to develop the research tools and procedures it needs where these are not being developed elsewhere. After almost twenty years of manned spaceflight activities and after a much longer period of space related ground-based research, the program now recognizes two characteristics of spaceflight which are truly unique to space. These are weightlessness and one specific form of radiation. In its present stage of maturity much of the research focuses on mechanisms underlying the basic responses of man and animals to weightlessness. The program consists of nine elements. Eight of these are referable to specific physiological problems that have either been encountered in previous manned spaceflight or which are anticipated to occur as spaceflights last longer, traverse steeper orbital inclinations, or are otherwise different from previous missions. The ninth addresses problems that have neither arisen nor can be reasonably predicted but are suspected on the basis of theoretical models, ground-based animal research, or for other reasons. The program's current emphasis is directed toward the motion sickness problem because of its relevance to Space Shuttle operations. Increased awareness and understanding of the radiation hazard has resulted in more emphasis being placed on the biological effects of high energy, high mass number particulate radiation and upon radiation protection . Cardiovascular and musculoskeleta1 studies are pursued in recognition of the considerable fundamental knowledge that must be acquired in these areas before effective countermeasures to the effects of repetitive or long-term flight can be devised. Major new avenues of research will deal with the psychological accompaniments of spaceflight and with mathematical modelling of physiological systems.
Obstacles to broadcasting for national integration in Nigeria.
Amienyi, O P
1989-01-01
In Nigeria, the media is the major government vehicle to achieve national integration. The problems arise from the approximately 250 ethnic groups speaking many languages. Television and radio have caused disintegration by emphasizing alienation and polarization rather than unity. With more than 178 languages there are major problems for radio and television. The government leaders have promoted a strong interest in creating a unified society through broadcasting, but at the same time have allowed media managers to operate towards goals of ethnic protection. Religion is also a factor that hinders broadcasting for national unity, since there are Hausa and Muslim in the north, Catholic in the south-east, and in the south-west there are many African ethnic religions. More than 60% of the local programming on television is keyed to local religious subjects. Illiteracy is also a problem in the use of broadcasting in the goal of national integration. Only through education of a socially conscious people can the religious fanaticism, ethnocentrism, and tribalism be overcome to form a united nation. Broadcasting can play an important role consistent with the needs of society as a whole. Managers in broadcasting must be well educated, well trained and understand the needs and ambitions of society. They need to support these needs and ambitions, and be constructively critical when necessary for the betterment of society.
A functional approach to cerebral visual impairments in very preterm/very-low-birth-weight children.
Geldof, Christiaan J A; van Wassenaer-Leemhuis, Aleid G; Dik, Marjolein; Kok, Joke H; Oosterlaan, Jaap
2015-08-01
Cerebral visual impairment (CVI) is a major cause of visual impairment, with very preterm birth/very low birth weight (VP/VLBW) being a major risk factor. There is no generally accepted definition of CVI. This study aims to investigate the usefulness of an empirically-based functional definition of CVI. One-hundred-five VP/VLBW children and 67 controls participated. CVI was defined after comprehensive oculomotor, visual sensory and perceptive assessment, and validated against vision problems in daily life and in terms of intellectual, behavioral, emotional and social functioning, as well as use of therapeutic services. Twenty-four per cent of the VP/VLBW children met criteria for CVI, compared to 7% of controls (P = 0.006, OR: 3.86, 95% CI: 1.40-10.70). VP/VLBW children with CVI had lower performance IQ, but not verbal IQ, than those without CVI. Visual problems in daily life were confirmed in VP/VLBW children classified with CVI. Additionally, difficulties in behavioral and social functioning were most prominent among VP/VLBW children with CVI. In VP/VLBW children, CVI defined in terms of visual function deficits is accompanied by intellectual, behavioral, and social impairments, validating our operational definition of CVI. CVI might act as a marker for developmental problems in VP/VLBW children.
Conditional quantum entropy power inequality for d-level quantum systems
NASA Astrophysics Data System (ADS)
Jeong, Kabgyun; Lee, Soojoon; Jeong, Hyunseok
2018-04-01
We propose an extension of the quantum entropy power inequality for finite dimensional quantum systems, and prove a conditional quantum entropy power inequality by using the majorization relation as well as the concavity of entropic functions also given by Audenaert et al (2016 J. Math. Phys. 57 052202). Here, we make particular use of the fact that a specific local measurement after a partial swap operation (or partial swap quantum channel) acting only on finite dimensional bipartite subsystems does not affect the majorization relation for the conditional output states when a separable ancillary subsystem is involved. We expect our conditional quantum entropy power inequality to be useful, and applicable in bounding and analyzing several capacity problems for quantum channels.
Development and operations of the Astrophysics Data System
NASA Technical Reports Server (NTRS)
Murray, S. S.
1993-01-01
The main effort in October 1992 was for the development and of the Astrophysics Data System (ADS) 3.1 graphical interface (GUI) and the preparation for its release. The beta-release for the GUI was made available to the nodes for testing. Development of the Abstract Server progressed satisfactorily. A test version was prepared for the ADASS meeting. Another major effort was the preparation for the user and nodes meetings on 5 and 6 November and for the ADASS conference on 2-4 November. February 1993 was highlighted by the preparation for the update release and its associated problems. We have the okay from the Commerce Department to export ADS. Foreign users can now sign on and receive the software. The main event during June was the AAS meeting. In the summer, the project decided on a new release schedule. The next major release is scheduled for January 1994 and will include major architectural improvements. In late spring 1994, a major release will include the new networking software.
Solid waste management in Abuja, Nigeria.
Imam, A; Mohammed, B; Wilson, D C; Cheeseman, C R
2008-01-01
The new city of Abuja provided an opportunity to avoid some of the environmental problems associated with other major cities in Africa. The current status of solid waste management in Abuja has been reviewed and recommendations for improvements are made. The existing solid waste management system is affected by unfavourable economic, institutional, legislative, technical and operational constraints. A reliable waste collection service is needed and waste collection vehicles need to be appropriate to local conditions. More vehicles are required to cope with increasing waste generation. Wastes need to be sorted at source as much as possible, to reduce the amount requiring disposal. Co-operation among communities, the informal sector, the formal waste collectors and the authorities is necessary if recycling rates are to increase. Markets for recycled materials need to be encouraged. Despite recent improvements in the operation of the existing dumpsite, a properly sited engineered landfill should be constructed with operation contracted to the private sector. Wastes dumped along roads, underneath bridges, in culverts and in drainage channels need to be cleared. Small-scale waste composting plants could promote employment, income generation and poverty alleviation. Enforcement of waste management legislation and a proper policy and planning framework for waste management are required. Unauthorized use of land must be controlled by enforcing relevant clauses in development guidelines. Accurate population data is necessary so that waste management systems and infrastructure can be properly planned. Funding and affordability remain major constraints and challenges.
Independent technical review, handbook
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Purpose Provide an independent engineering review of the major projects being funded by the Department of Energy, Office of Environmental Restoration and Waste Management. The independent engineering review will address questions of whether the engineering practice is sufficiently developed to a point where a major project can be executed without significant technical problems. The independent review will focus on questions related to: (1) Adequacy of development of the technical base of understanding; (2) Status of development and availability of technology among the various alternatives; (3) Status and availability of the industrial infrastructure to support project design, equipment fabrication, facility construction,more » and process and program/project operation; (4) Adequacy of the design effort to provide a sound foundation to support execution of project; (5) Ability of the organization to fully integrate the system, and direct, manage, and control the execution of a complex major project.« less
Boden, Ianthe; Browning, Laura; Skinner, Elizabeth H; Reeve, Julie; El-Ansary, Doa; Robertson, Iain K; Denehy, Linda
2015-12-15
Post-operative pulmonary complications are a significant problem following open upper abdominal surgery. Preliminary evidence suggests that a single pre-operative physiotherapy education and preparatory lung expansion training session alone may prevent respiratory complications more effectively than supervised post-operative breathing and coughing exercises. However, the evidence is inconclusive due to methodological limitations. No well-designed, adequately powered, randomised controlled trial has investigated the effect of pre-operative education and training on post-operative respiratory complications, hospital length of stay, and health-related quality of life following upper abdominal surgery. The Lung Infection Prevention Post Surgery - Major Abdominal- with Pre-Operative Physiotherapy (LIPPSMAck POP) trial is a pragmatic, investigator-initiated, bi-national, multi-centre, patient- and assessor-blinded, parallel group, randomised controlled trial, powered for superiority. Four hundred and forty-one patients scheduled for elective open upper abdominal surgery at two Australian and one New Zealand hospital will be randomised using concealed allocation to receive either i) an information booklet or ii) an information booklet, plus one additional pre-operative physiotherapy education and training session. The primary outcome is respiratory complication incidence using standardised diagnostic criteria. Secondary outcomes include hospital length of stay and costs, pneumonia diagnosis, intensive care unit readmission and length of stay, days/h to mobilise >1 min and >10 min, and, at 6 weeks post-surgery, patient reported complications, health-related quality of life, and physical capacity. The LIPPSMAck POP trial is a multi-centre randomised controlled trial powered and designed to investigate whether a single pre-operative physiotherapy session prevents post-operative respiratory complications. This trial standardises post-operative assisted ambulation and physiotherapy, measures many known confounders, and includes a post-discharge follow-up of complication rates, functional capacity, and health-related quality of life. This trial is currently recruiting. Australian New Zealand Clinical Trials Registry number: ACTRN12613000664741 , 19 June 2013.
Institutional profile: the London Centre for Nanotechnology.
Weston, David; Bontoux, Thierry
2009-12-01
Located in the London neighborhoods of Bloomsbury and South Kensington, the London Centre for Nanotechnology is a UK-based multidisciplinary research center that operates at the forefront of science and technology. It is a joint venture between two of the world's leading institutions, UCL and Imperial College London, uniting their strong capabilities in the disciplines that underpin nanotechnology: engineering, the physical sciences and biomedicine. The London Centre for Nanotechnology has a unique operating model that accesses and focuses the combined skills of the Departments of Chemistry, Physics, Materials, Medicine, Electrical and Electronic Engineering, Mechanical Engineering, Chemical Engineering, Biochemical Engineering and Earth Sciences across the two universities. It aims to provide the nanoscience and nanotechnology required to solve major problems in healthcare, information processing, energy and the environment.
Database usage and performance for the Fermilab Run II experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bonham, D.; Box, D.; Gallas, E.
2004-12-01
The Run II experiments at Fermilab, CDF and D0, have extensive database needs covering many areas of their online and offline operations. Delivering data to users and processing farms worldwide has represented major challenges to both experiments. The range of applications employing databases includes, calibration (conditions), trigger information, run configuration, run quality, luminosity, data management, and others. Oracle is the primary database product being used for these applications at Fermilab and some of its advanced features have been employed, such as table partitioning and replication. There is also experience with open source database products such as MySQL for secondary databasesmore » used, for example, in monitoring. Tools employed for monitoring the operation and diagnosing problems are also described.« less
Experiment T002: Manual navigation sightings
NASA Technical Reports Server (NTRS)
Smith, D.
1971-01-01
Navigation-type measurements through the window of the stabilized Gemini 12 spacecraft by the use of a hand-held sextant are reported. The major objectives were as follows: (1) to evaluate the ability of the crewmen to make accurate navigational measurements by the use of simple instruments in an authentic space flight environment; (2) to evaluate the operational feasibility of the measurement techniques by the use of the pressure suit with the helmet off and with the helmet on and the visor closed; (3) to evaluate operational problems associated with the spacecraft environment; and (4) to validate ground based simulation techniques by comparison of the inflight results with base line data obtained by the pilot by the use of simulators and celestial targets from ground based observatories.
Asymptotic state discrimination and a strict hierarchy in distinguishability norms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chitambar, Eric; Hsieh, Min-Hsiu
2014-11-15
In this paper, we consider the problem of discriminating quantum states by local operations and classical communication (LOCC) when an arbitrarily small amount of error is permitted. This paradigm is known as asymptotic state discrimination, and we derive necessary conditions for when two multipartite states of any size can be discriminated perfectly by asymptotic LOCC. We use this new criterion to prove a gap in the LOCC and separable distinguishability norms. We then turn to the operational advantage of using two-way classical communication over one-way communication in LOCC processing. With a simple two-qubit product state ensemble, we demonstrate a strictmore » majorization of the two-way LOCC norm over the one-way norm.« less
Reconfigurability in MDO Problem Synthesis. Part 1
NASA Technical Reports Server (NTRS)
Alexandrov, Natalia M.; Lewis, Robert Michael
2004-01-01
Integrating autonomous disciplines into a problem amenable to solution presents a major challenge in realistic multidisciplinary design optimization (MDO). We propose a linguistic approach to MDO problem description, formulation, and solution we call reconfigurable multidisciplinary synthesis (REMS). With assistance from computer science techniques, REMS comprises an abstract language and a collection of processes that provide a means for dynamic reasoning about MDO problems in a range of contexts. The approach may be summarized as follows. Description of disciplinary data according to the rules of a grammar, followed by lexical analysis and compilation, yields basic computational components that can be assembled into various MDO problem formulations and solution algorithms, including hybrid strategies, with relative ease. The ability to re-use the computational components is due to the special structure of the MDO problem. The range of contexts for reasoning about MDO spans tasks from error checking and derivative computation to formulation and reformulation of optimization problem statements. In highly structured contexts, reconfigurability can mean a straightforward transformation among problem formulations with a single operation. We hope that REMS will enable experimentation with a variety of problem formulations in research environments, assist in the assembly of MDO test problems, and serve as a pre-processor in computational frameworks in production environments. This paper, Part 1 of two companion papers, discusses the fundamentals of REMS. Part 2 illustrates the methodology in more detail.
Reconfigurability in MDO Problem Synthesis. Part 2
NASA Technical Reports Server (NTRS)
Alexandrov, Natalia M.; Lewis, Robert Michael
2004-01-01
Integrating autonomous disciplines into a problem amenable to solution presents a major challenge in realistic multidisciplinary design optimization (MDO). We propose a linguistic approach to MDO problem description, formulation, and solution we call reconfigurable multidisciplinary synthesis (REMS). With assistance from computer science techniques, REMS comprises an abstract language and a collection of processes that provide a means for dynamic reasoning about MDO problems in a range of contexts. The approach may be summarized as follows. Description of disciplinary data according to the rules of a grammar, followed by lexical analysis and compilation, yields basic computational components that can be assembled into various MDO problem formulations and solution algorithms, including hybrid strategies, with relative ease. The ability to re-use the computational components is due to the special structure of the MDO problem. The range of contexts for reasoning about MDO spans tasks from error checking and derivative computation to formulation and reformulation of optimization problem statements. In highly structured contexts, reconfigurability can mean a straightforward transformation among problem formulations with a single operation. We hope that REMS will enable experimentation with a variety of problem formulations in research environments, assist in the assembly of MDO test problems, and serve as a pre-processor in computational frameworks in production environments. Part 1 of two companion papers, discusses the fundamentals of REMS. This paper, Part 2 illustrates the methodology in more detail.
Aviation safety and operation problems research and technology
NASA Technical Reports Server (NTRS)
Enders, J. H.; Strickle, J. W.
1977-01-01
Aircraft operating problems are described for aviation safety. It is shown that as aircraft technology improves, the knowledge and understanding of operating problems must also improve for economics, reliability and safety.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davison, B.H.; Klasson, K.T.; Barton, J.W.
1998-06-01
'Biofiltration systems can be used for treatment of volatile organic compounds (VOCs); however, the systems are poorly understood and are currently operated as black boxes. Common operational problems associated with biofilters include fouling, deactivation, and overgrowth, all of which make them ineffective for continuous, long-term use. The objective of this investigation is to develop generic methods for long-term stable operation, in particular by using selective limitation of supplemental nutrients while maintaining high activity. As part of this effort, the author will provide deeper fundamental understanding of the important biological and transport mechanisms in biodestruction of sparingly soluble VOCs and extendmore » this approach and mathematical models to additional systems of high priority EM relevance--direct degradation and cometabolic degradation of priority pollutants such as BTEX and chlorinated organics. This report summarizes work after 2 years of a 3-year project. Major results are enumerated and discussed'« less
Reassessing the plight of physician organizations in California: the uncertain future for IPAs.
Trauner, J B
2000-07-01
With numerous medical groups and individual practice associations (IPAs) in California now reporting operating losses--and many approaching financial insolvency--the question arises why physician organizations are in such a tenuous situation. One line of thinking is that the problem is attributable to the market dominance of the major health plans and their ability to impose actuarially unsound low capitation rates on professional providers. This article describes four other reasons for the current plight of physician organizations: (1) a physician-centric approach to IPA governance, (2) lack of qualified staff within key operating units, (3) management reporting that is insufficient to support utilization analysis and health plan negotiations, and (4) a highly charged political process for determining physician reimbursement. IPA survival will ultimately depend upon whether IPAs are perceived by their physician members and leaders as true business operations or just as another income source.
Operational flow visualization techniques in the Langley Unitary Plan Wind Tunnel
NASA Technical Reports Server (NTRS)
Corlett, W. A.
1982-01-01
The unitary plan wind tunnel (UPWT) uses in daily operation are shown. New ideas for improving the quality of established flow visualization methods are developed and programs on promising new flow visualization techniques are pursued. The unitary plan wind tunnel is a supersonic facility, referred to as a production facility, although the majority of tests are inhouse basic research investigations. The facility has two 4 ft. by 4 ft. test sections which span a Mach range from 1.5 to 4.6. The cost of operation is about $10 per minute. Problems are the time required for a flow visualization test setup and investigation costs and the ability to obtain consistently repeatable results. Examples of sublimation, vapor screen, oil flow, minitufts, schlieren, and shadowgraphs taken in UPWT are presented. All tests in UPWT employ one or more of the flow visualization techniques.
Choobineh, A R; Daneshmandi, H; Aghabeigi, M; Haghayegh, A
2013-10-01
Work-related musculoskeletal disorders (WMSDs) are a common health problem throughout the world and a major cause of disability in the workplace. To determine the prevalence rate of MSDs, assessment of ergonomics working conditions and identification of major risk factors associated with MSDs symptoms among employees of Iranian petrochemical industries between October 2009 and December 2012. In this study, we studied 1184 randomly selected employees of 4 Iranian petrochemical companies with at least one year of work experience in office or operational units. For those with office jobs, data were collected using Nordic Musculoskeletal disorders Questionnaire (NMQ) and ergonomics checklist for the assessment of working conditions. For those with operational jobs, NMQ and Quick Exposure Check (QEC) method were used for data collection. The most prevalent MSD symptoms were reported in lower back (41.5%) and neck (36.5%). The prevalence of MSDs in all body regions but elbows and thighs of the office staff was significantly higher than that of operational workers. Assessment of working conditions in office staff revealed that the lowest index was attributed to workstation. QEC technique among operational workers showed that in 73.8% of the workers studied, the level of exposure to musculoskeletal risks was "high" or "very high." MSDs were associated with type of job, age, body mass index, work experience, gender, marital status, educational level and type of employment. The prevalence of MSDs in the office staff was higher than that of operational workers. Level of exposure to MSDs risk was high in operational workers. Corrective measures are thus necessary for improving working conditions for both office and operational units.
Prevalence of DSM-IV major depression among U.S. military personnel: meta-analysis and simulation.
Gadermann, Anne M; Engel, Charles C; Naifeh, James A; Nock, Matthew K; Petukhova, Maria; Santiago, Patcho N; Wu, Benjamin; Zaslavsky, Alan M; Kessler, Ronald C
2012-08-01
A meta-analysis of 25 epidemiological studies estimated the prevalence of recent Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) major depression (MD) among U.S. military personnel. Best estimates of recent prevalence (standard error) were 12.0% (1.2) among currently deployed, 13.1% (1.8) among previously deployed, and 5.7% (1.2) among never deployed. Consistent correlates of prevalence were being female, enlisted, young (ages 17-25), unmarried, and having less than a college education. Simulation of data from a national general population survey was used to estimate expected lifetime prevalence of MD among respondents with the sociodemographic profile and none of the enlistment exclusions of Army personnel. In this Simulated sample, 16.2% (3.1) of respondents had lifetime MD and 69.7% (8.5) of first onsets occurred before expected age of enlistment. Numerous methodological problems limit the results of the meta-analysis and simulation. The article closes with a discussion of recommendations for correcting these problems in future surveillance and operational stress studies.
Kebede Deyyas, Wakjira; Tafese, Ararso
2014-01-01
Occupational health problems related to upper limp musculoskeletal disorders were the major issue among sewing machine operators of garment industries in Ethiopia. The aim of this study was to assess the prevalence and associated risk factors of work related elbow and wrist musculoskeletal disorders among sewing machine operators of garment industries in Galan City, Oromia Regional State. A cross-sectional study was conducted from April 1 to 30, 2012. A total of 422 study subjects were included in this study. Standard Nordic Musculoskeletal Questionnaire was used to collect detailed information on musculoskeletal symptom, sociodemographic data, and factors associated with the problems through face to face interview. From a total of 422 sewing machine operators included in the study 370 (87.7%) were females and 306 (72.5%) were in the age group of <30 years. The prevalence of self-reported work related elbow and wrist musculoskeletal disorders was 40% and 37.7%, respectively. In multivariate analysis, those who had >16 years of service were about five times more likely to develop elbow and wrist musculoskeletal disorders than those who had short (1-5 years) year of services [AOR = 4.7, 95% CI: 1.55-13.02], physical activities [AOR = 5.02, 95% CI: 1.57-16.00], and methods of payment [AOR = 2.01, 95% CI: 1.23-3.28], factors significantly associated with this disorders. Work related elbow and wrist musculoskeletal disorders were high among sewing machine operators in selected garment industries. Moreover, personal and environmental factors were identified as the potential risk factors related to elbow and wrist musculoskeletal disorders among the study group. Therefore, government and the owner of the garment industries should give special attention to prevent and control the problems through proper occupational health and safety policy implementation in the country.
Kebede Deyyas, Wakjira; Tafese, Ararso
2014-01-01
Occupational health problems related to upper limp musculoskeletal disorders were the major issue among sewing machine operators of garment industries in Ethiopia. The aim of this study was to assess the prevalence and associated risk factors of work related elbow and wrist musculoskeletal disorders among sewing machine operators of garment industries in Galan City, Oromia Regional State. A cross-sectional study was conducted from April 1 to 30, 2012. A total of 422 study subjects were included in this study. Standard Nordic Musculoskeletal Questionnaire was used to collect detailed information on musculoskeletal symptom, sociodemographic data, and factors associated with the problems through face to face interview. From a total of 422 sewing machine operators included in the study 370 (87.7%) were females and 306 (72.5%) were in the age group of <30 years. The prevalence of self-reported work related elbow and wrist musculoskeletal disorders was 40% and 37.7%, respectively. In multivariate analysis, those who had >16 years of service were about five times more likely to develop elbow and wrist musculoskeletal disorders than those who had short (1–5 years) year of services [AOR = 4.7, 95% CI: 1.55–13.02], physical activities [AOR = 5.02, 95% CI: 1.57–16.00], and methods of payment [AOR = 2.01, 95% CI: 1.23–3.28], factors significantly associated with this disorders. Work related elbow and wrist musculoskeletal disorders were high among sewing machine operators in selected garment industries. Moreover, personal and environmental factors were identified as the potential risk factors related to elbow and wrist musculoskeletal disorders among the study group. Therefore, government and the owner of the garment industries should give special attention to prevent and control the problems through proper occupational health and safety policy implementation in the country. PMID:25298780
DOE Office of Scientific and Technical Information (OSTI.GOV)
Faybishenko, Boris; Birkholzer, Jens; Sassani, David
The overall objective of the Fifth Worldwide Review (WWR-5) is to document the current state-of-the-art of major developments in a number of nations throughout the World pursuing geological disposal programs, and to summarize challenging problems and experience that have been obtained in siting, preparing and reviewing cases for the operational and long-term safety of proposed and operating nuclear waste repositories. The scope of the Review is to address current specific technical issues and challenges in safety case development along with the interplay of technical feasibility, siting, engineering design issues, and operational and post-closure safety. In particular, the chapters included inmore » the report present the following types of information: the current status of the deep geological repository programs for high level nuclear waste and low- and intermediate level nuclear waste in each country, concepts of siting and radioactive waste and spent nuclear fuel management in different countries (with the emphasis of nuclear waste disposal under different climatic conditions and different geological formations), progress in repository site selection and site characterization, technology development, buffer/backfill materials studies and testing, support activities, programs, and projects, international cooperation, and future plans, as well as regulatory issues and transboundary problems.« less
2013-01-01
The HIV-1 virus can enter a dormant state and become inactive, which reduces accessibility by antiviral drugs. We approach this latency problem from an unconventional point of view, with the focus on understanding how intrinsic chemical noise (copy number fluctuations of the Tat protein) can be used to assist the activation process of the latent virus. Several phase diagrams have been constructed in order to visualize in which regions of the parameter space noise can drive the activation process. Essential to the study is the use of a hyperbolic coordinate system, which greatly facilitates quantification of how the various reaction rate combinations shape the noise behavior of the Tat protein feedback system. We have designed a mathematical manual of how to approach the problem of activation quantitatively, and introduce the notion of an “operating point” of the virus. For both noise-free and noise-based strategies we show how operating point off-sets induce changes in the number of Tat molecules. The major result of the analysis is that for every noise-free strategy there is a noise-based strategy that requires lower dosage, but achieves the same anti-latency effect. It appears that the noise-based activation is advantageous for every operating point. PMID:23497153
Mod-2 wind turbine field operations experiment
NASA Technical Reports Server (NTRS)
Gordon, L. H.
1985-01-01
The three-machine, 7.5 MW Goodnoe Hills located near Goldendale, Washington and is now in a research/experimental operations phase that offers a unique opportunity to study the effects of single and multiple wind turbines interacting with each other, the power grid; and the environment. Following a brief description of the turbine and project history, this paper addresses major problem areas and research and development test results. Field operations, both routine and nonroutine, are discussed. Routine operation to date has produced over 13,379,000 KWh of electrical energy during 11,064 hr of rotation. Nonroutine operation includes suspended activities caused by a crack in the low speed shaft that necessitated a redesign and reinstallation of this assembly on all three turbines. With the world's largest cluster back in full operation, two of the turbines will be operated over the next years to determine their value as energy producer. The third unit will be used primarily for conducting research tests requiring configuration changes to better understand the wind turbine technology. Technical areas summarized pertain to system performance and enhancements. Specific research tests relating to acoustics, TV interference, and wake effects conclude the paper.
Automated Design of Noise-Minimal, Safe Rotorcraft Trajectories
NASA Technical Reports Server (NTRS)
Morris, Robert A.; Venable, K. Brent; Lindsay, James
2012-01-01
NASA and the international community are investing in the development of a commercial transportation infrastructure that includes the increased use of rotorcraft, specifically helicopters and aircraft such as a 40-passenger civil tilt rotors. Rotorcraft have a number of advantages over fixed wing aircraft, primarily in not requiring direct access to the primary fixed wing runways. As such they can operate at an airport without directly interfering with major air carrier and commuter aircraft operations. However, there is significant concern over the impact of noise on the communities surrounding the transportation facilities. In this paper we propose to address the rotorcraft noise problem by exploiting powerful search techniques coming from artificial intelligence, coupled with simulation and field tests, to design trajectories that are expected to improve on the amount of ground noise generated. This paper investigates the use of simulation based on predictive physical models to facilitate the search for low-noise trajectories using a class of automated search algorithms called local search. A novel feature of this approach is the ability to incorporate constraints into the problem formulation that addresses passenger safety and comfort.
Hessian-based norm regularization for image restoration with biomedical applications.
Lefkimmiatis, Stamatios; Bourquard, Aurélien; Unser, Michael
2012-03-01
We present nonquadratic Hessian-based regularization methods that can be effectively used for image restoration problems in a variational framework. Motivated by the great success of the total-variation (TV) functional, we extend it to also include second-order differential operators. Specifically, we derive second-order regularizers that involve matrix norms of the Hessian operator. The definition of these functionals is based on an alternative interpretation of TV that relies on mixed norms of directional derivatives. We show that the resulting regularizers retain some of the most favorable properties of TV, i.e., convexity, homogeneity, rotation, and translation invariance, while dealing effectively with the staircase effect. We further develop an efficient minimization scheme for the corresponding objective functions. The proposed algorithm is of the iteratively reweighted least-square type and results from a majorization-minimization approach. It relies on a problem-specific preconditioned conjugate gradient method, which makes the overall minimization scheme very attractive since it can be applied effectively to large images in a reasonable computational time. We validate the overall proposed regularization framework through deblurring experiments under additive Gaussian noise on standard and biomedical images.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The Computing and Communications (C) Division is responsible for the Laboratory's Integrated Computing Network (ICN) as well as Laboratory-wide communications. Our computing network, used by 8,000 people distributed throughout the nation, constitutes one of the most powerful scientific computing facilities in the world. In addition to the stable production environment of the ICN, we have taken a leadership role in high-performance computing and have established the Advanced Computing Laboratory (ACL), the site of research on experimental, massively parallel computers; high-speed communication networks; distributed computing; and a broad variety of advanced applications. The computational resources available in the ACL are ofmore » the type needed to solve problems critical to national needs, the so-called Grand Challenge'' problems. The purpose of this publication is to inform our clients of our strategic and operating plans in these important areas. We review major accomplishments since late 1990 and describe our strategic planning goals and specific projects that will guide our operations over the next few years. Our mission statement, planning considerations, and management policies and practices are also included.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The Computing and Communications (C) Division is responsible for the Laboratory`s Integrated Computing Network (ICN) as well as Laboratory-wide communications. Our computing network, used by 8,000 people distributed throughout the nation, constitutes one of the most powerful scientific computing facilities in the world. In addition to the stable production environment of the ICN, we have taken a leadership role in high-performance computing and have established the Advanced Computing Laboratory (ACL), the site of research on experimental, massively parallel computers; high-speed communication networks; distributed computing; and a broad variety of advanced applications. The computational resources available in the ACL are ofmore » the type needed to solve problems critical to national needs, the so-called ``Grand Challenge`` problems. The purpose of this publication is to inform our clients of our strategic and operating plans in these important areas. We review major accomplishments since late 1990 and describe our strategic planning goals and specific projects that will guide our operations over the next few years. Our mission statement, planning considerations, and management policies and practices are also included.« less
Heat pump study: Tricks of the trade that can pump up efficiency
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jenkins, V.
Two years ago, many homeowners in an area near Auburn, California were unhappy with their heat pumps. The local utility, Pacific Gas Electric (PG E), received unusually large numbers of complaints from them of high electricity bills and poor system operation. PG E wanted to know whether correctable mechanical problems were to blame. It hired John Proctor, then of Building Resources Management Corp., to design and implement a study to address the heat pump customers' complaints. The Pacific Gas Electric Heat Pump Efficiency and Super Weatherization Pilot Project was the result. The first objective of the Pilot Project was tomore » identify the major problems and their prevalence in the existing residential heat pump installations. The second was to design a correction strategy that would cost PG E $400 or less per site. Participating homeowners would also share some of the costs. Project goals were improved homeowner comfort and satisfaction, increased energy efficiency of mechanical systems, and 10-20% space heating energy savings. By improving system operations, the project wished to increase customer acceptance of heat pumps in general.« less
Salvage reconstruction of failed interposition arthroplasty at the base of the thumb.
Braun, Richard M; Rechnic, Mark; Shah, Kalpit N
2012-12-01
We present an operative procedure designed to revise a failed arthroplasty at the base of the thumb. This report describes a reliable operation that corrects residual instability and malignment which results in thumbs that are weak and painful despite a previous procedure. The operation has also been used as a primary procedure for arthritis of the trapeziometacarpal joint where instability and subluxation was a major component of the problem requiring joint reconstruction. The unique features of this procedure include a reinforced double-thickness tendon graft, a unique tendon anchor, and a fascia lata allograft spacer. Significant functional improvement is anticipated when joint reconstruction provides increased proximal stability. Pinch and grip measurements improve. Pain scores also diminish after the operation. Hand function and patient satisfaction can be substantially improved with revision arthroplasty when the initial operation has failed to provide a thumb that is mobile, stable, and pain free. The technical features of the procedure address reduction of malignment, restoring of anatomic balance, and secure fixation of the proximal apex of the thumb metacarpal which restores thumb reduction position and digital balance.
Science modelling in pre-calculus: how to make mathematics problems contextually meaningful
NASA Astrophysics Data System (ADS)
Sokolowski, Andrzej; Yalvac, Bugrahan; Loving, Cathleen
2011-04-01
'Use of mathematical representations to model and interpret physical phenomena and solve problems is one of the major teaching objectives in high school math curriculum' (National Council of Teachers of Mathematics (NCTM), Principles and Standards for School Mathematics, NCTM, Reston, VA, 2000). Commonly used pre-calculus textbooks provide a wide range of application problems. However, these problems focus students' attention on evaluating or solving pre-arranged formulas for given values. The role of scientific content is reduced to provide a background for these problems instead of being sources of data gathering for inducing mathematical tools. Students are neither required to construct mathematical models based on the contexts nor are they asked to validate or discuss the limitations of applied formulas. Using these contexts, the instructor may think that he/she is teaching problem solving, where in reality he/she is teaching algorithms of the mathematical operations (G. Kulm (ed.), New directions for mathematics assessment, in Assessing Higher Order Thinking in Mathematics, Erlbaum, Hillsdale, NJ, 1994, pp. 221-240). Without a thorough representation of the physical phenomena and the mathematical modelling processes undertaken, problem solving unintentionally appears as simple algorithmic operations. In this article, we deconstruct the representations of mathematics problems from selected pre-calculus textbooks and explicate their limitations. We argue that the structure and content of those problems limits students' coherent understanding of mathematical modelling, and this could result in weak student problem-solving skills. Simultaneously, we explore the ways to enhance representations of those mathematical problems, which we have characterized as lacking a meaningful physical context and limiting coherent student understanding. In light of our discussion, we recommend an alternative to strengthen the process of teaching mathematical modelling - utilization of computer-based science simulations. Although there are several exceptional computer-based science simulations designed for mathematics classes (see, e.g. Kinetic Book (http://www.kineticbooks.com/) or Gizmos (http://www.explorelearning.com/)), we concentrate mainly on the PhET Interactive Simulations developed at the University of Colorado at Boulder (http://phet.colorado.edu/) in generating our argument that computer simulations more accurately represent the contextual characteristics of scientific phenomena than their textual descriptions.
The birth of numerical weather prediction
NASA Astrophysics Data System (ADS)
Wiin-Nielsen, A.
1991-08-01
The paper describes the major events leading gradually to operational, numerical, short-range predictions for the large-scale atmospheric flow. The theoretical foundation starting with Rossby's studies of the linearized, barotropic equation and ending a decade and a half later with the general formulation of the quasi-geostrophic, baroclinic model by Charney and Phillips is described. The problems connected with the very long waves and the inconsistences of the geostrophic approximation which were major obstacles in the first experimental forecasts are discussed. The resulting changes to divergent barotropic and baroclinic models and to the use of the balance equation are described. After the discussion of the theoretical foundation, the paper describes the major developments leading to the Meteorology Project at the Institute for Advanced Studied under the leadership of John von Neumann and Jule Charney followed by the establishment of the Joint Numerical Weather Prediction Unit in Suitland, Maryland. The interconnected developments in Europe, taking place more-or-less at the same time, are described by concentrating on the activities in Stockholm where the barotropic model was used in many experiments leading also to operational forecasts. The further developments resulting in the use of the primitive equations and the formulation of medium-range forecasting models are not included in the paper.
The birth of numerical weather prediction
NASA Astrophysics Data System (ADS)
Wiin-Nielsen, A.
1991-09-01
The paper describes the major events leading gradually to operational, numerical, short-range predictions for the large-scale atmospheric flow. The theoretical foundation starting with Rossby's studies of the linearized, barotropic equation and ending a decade and a half later with the general formulation of the quasi-geostrophic, baroclinic model by Charney and Phillips is described. The problems connected with the very long waves and the inconsistences of the geostrophic approximation which were major obstacles in the first experimental forecasts are discussed. The resulting changes to divergent barotropic and baroclinic models and to the use of the balance equation are described. After the discussion of the theoretical foundation, the paper describes the major developments leading to the Meteorology Project at the Institute for Advanced Studied under the leadership of John von Neumann and Jule Charney followed by the establishment of the Joint Numerical Weather Prediction Unit in Suitland, Maryland. The inter-connected developments in Europe, taking place more-or-less at the same time, are described by concentrating on the activities in Stockholm where the barotropic model was used in many experiments leading also to operational forecasts. The further developments resulting in the use of the primitive equations and the formulation of medium-range forecasting models are not included in the paper.
How do the top 12 pharmaceutical companies operate safety pharmacology?
Ewart, Lorna; Gallacher, David J; Gintant, Gary; Guillon, Jean-Michel; Leishman, Derek; Levesque, Paul; McMahon, Nick; Mylecraine, Lou; Sanders, Martin; Suter, Willi; Wallis, Rob; Valentin, Jean-Pierre
2012-09-01
How does safety pharmacology operate in large pharmaceutical companies today? By understanding our current position, can we prepare safety pharmacology to successfully navigate the complex process of drug discovery and development? A short anonymous survey was conducted, by invitation, to safety pharmacology representatives of the top 12 pharmaceutical companies, as defined by 2009 revenue figures. A series of multiple choice questions was designed to explore group size, accountabilities, roles and responsibilities of group members, outsourcing policy and publication record. A 92% response rate was obtained. Six out of 11 companies have 10 to 30 full time equivalents in safety pharmacology, who hold similar roles and responsibilities; although the majority of members are not qualified at PhD level or equivalent. Accountabilities were similar across companies and all groups have accountability for core battery in vivo studies and problem solving activities but differences do exist for example with in vitro safety screening and pharmacodynamic/pharmokinetic modeling (PK/PD). The majority of companies outsource less than 25% of studies, with in vitro profiling being the most commonly outsourced activity. Finally, safety pharmacology groups are publishing 1 to 4 articles each year. This short survey has highlighted areas of similarity and differences in the way large pharmaceutical companies operate safety pharmacology. Copyright © 2012 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sommer, T.; Melick, T.; Morrison, D.
The objective of this DOE sponsored project was to successfully fire coal-water slurry in a fire-tube boiler that was designed for oil/gas firing and establish a data base that will be relevant to a large number of existing installations. Firing slurry in a fire-tube configuration is a very demanding application because of the extremely high heat release rates and the correspondingly low furnace volume where combustion can be completed. Recognizing that combustion efficiency is the major obstacle when firing slurry in a fire-tube boiler, the program was focused on innovative approaches for improving carbon burnout without major modifications to themore » boiler. The boiler system was successfully designed and operated to fire coal-water slurry for extended periods of time with few slurry related operational problems. The host facility was a 3.8 million Btu/hr Cleaver-Brooks fire-tube boiler located on the University of Alabama Campus. A slurry atomizer was designed that provided outstanding atomization and was not susceptible to pluggage. The boiler was operated for over 1000 hours and 12 shipments of slurry were delivered. The new equipment engineered for the coal-water slurry system consisted of the following: combustion air and slurry heaters; cyclone; baghouse; fly ash reinjection system; new control system; air compressor; CWS/gas burner and gas valve train; and storage tank and slurry handling system.« less
Ait Khelifa-Gallois, N; Laroussinie, F; Puget, S; Sainte-Rose, C; Dellatolas, G
2015-01-01
Abstract Purpose: A number of studies report neurological and cognitive deficits and behavioural disorders in children after surgical treatment for a benign cerebellar tumour. The present study explores functional outcome in adolescents and adults treated for a low-grade cerebellar astrocytoma in childhood. Participants were 18 adolescents and 46 adults treated for low-grade astrocytoma in childhood. Academic achievement, professional status and neurological, cognitive and behavioural disturbances were collected using self-completed and parental questionnaires for adolescents and phone interview for adults. For the adolescent group, a control group filled in the same questionnaires. Mean time lapse from surgery was 7.8 years for adolescents and 12.9 years for adults. Five adults (11%) had major sequelae related to post-operative complications, post-operative mutism and/or brain stem involvement. All the other participants presented close-to-normal academic achievement and normal autonomy, despite a high rate of reported cognitive difficulties and difficulties related to mild neurological sequelae (fine motor skills, balance). The long-term functional outcome of low-grade cerebellar astrocytoma is generally favourable, in the absence of post-operative complications and brain stem involvement. No major impact of neurological deficits, cognitive problems and emotional disorders on academic achievement and independent functioning was observed.
Integration of Wind Turbines with Compressed Air Energy Storage
NASA Astrophysics Data System (ADS)
Arsie, I.; Marano, V.; Rizzo, G.; Moran, M.
2009-08-01
Some of the major limitations of renewable energy sources are represented by their low power density and intermittent nature, largely depending upon local site and unpredictable weather conditions. These problems concur to increase the unit costs of wind power, so limiting their diffusion. By coupling storage systems with a wind farm, some of the major limitations of wind power, such as a low power density and an unpredictable nature, can be overcome. After an overview on storage systems, the Compressed Air Energy Storage (CAES) is analyzed, and the state of art on such systems is discussed. A Matlab/Simulink model of a hybrid power plant consisting of a wind farm coupled with CAES is then presented. The model has been successfully validated starting from the operating data of the McIntosh CAES Plant in Alabama. Time-series neural network-based wind speed forecasting are employed to determine the optimal daily operation strategy for the storage system. A detailed economic analysis has been carried out: investment and maintenance costs are estimated based on literature data, while operational costs and revenues are calculated according to energy market prices. As shown in the paper, the knowledge of the expected available energy is a key factor to optimize the management strategies of the proposed hybrid power plant, allowing to obtain environmental and economic benefits.
NASA Technical Reports Server (NTRS)
Houston, A. G.; Feiveson, A. H.; Chhikara, R. S.; Hsu, E. M. (Principal Investigator)
1979-01-01
A statistical methodology was developed to check the accuracy of the products of the experimental operations throughout crop growth and to determine whether the procedures are adequate to accomplish the desired accuracy and reliability goals. It has allowed the identification and isolation of key problems in wheat area yield estimation, some of which have been corrected and some of which remain to be resolved. The major unresolved problem in accuracy assessment is that of precisely estimating the bias of the LACIE production estimator. Topics covered include: (1) evaluation techniques; (2) variance and bias estimation for the wheat production estimate; (3) the 90/90 evaluation; (4) comparison of the LACIE estimate with reference standards; and (5) first and second order error source investigations.
The Complexities of Implementing Cluster Supply Chain - Case Study of JCH
NASA Astrophysics Data System (ADS)
Xue, Xiao; Zhang, Jibiao; Wang, Yang
As a new type of management pattern, "cluster supply chain" (CSC) can help SMEs to face the global challenges through all kinds of collaboration. However, a major challenge in implementing CSC is the gap between theory and practice in the field. In an effort to provide a better understanding of this emerging phenomenon, this paper presents the implementation process of CSC in the context of JingCheng Mechanical & Electrical Holding co., ltd.(JCH) as a case study. The cast study of JCH suggests that the key problems in the practice of cluster supply chain: How do small firms use cluster supply chain? Only after we clarify the problem, the actual construction and operation of cluster supply chain does show successful results as it should be.
Distributed photovoltaic systems: Utility interface issues and their present status
NASA Technical Reports Server (NTRS)
Hassan, M.; Klein, J.
1981-01-01
Major technical issues involving the integration of distributed photovoltaics (PV) into electric utility systems are defined and their impacts are described quantitatively. An extensive literature search, interviews, and analysis yielded information about the work in progress and highlighted problem areas in which additional work and research are needed. The findings from the literature search were used to determine whether satisfactory solutions to the problems exist or whether satisfactory approaches to a solution are underway. It was discovered that very few standards, specifications, or guidelines currently exist that will aid industry in integrating PV into the utility system. Specific areas of concern identified are: (1) protection, (2) stability, (3) system unbalance, (4) voltage regulation and reactive power requirements, (5) harmonics, (6) utility operations, (7) safety, (8) metering, and (9) distribution system planning and design.
Genetic Algorithm Approaches for Actuator Placement
NASA Technical Reports Server (NTRS)
Crossley, William A.
2000-01-01
This research investigated genetic algorithm approaches for smart actuator placement to provide aircraft maneuverability without requiring hinged flaps or other control surfaces. The effort supported goals of the Multidisciplinary Design Optimization focus efforts in NASA's Aircraft au program. This work helped to properly identify various aspects of the genetic algorithm operators and parameters that allow for placement of discrete control actuators/effectors. An improved problem definition, including better definition of the objective function and constraints, resulted from this research effort. The work conducted for this research used a geometrically simple wing model; however, an increasing number of potential actuator placement locations were incorporated to illustrate the ability of the GA to determine promising actuator placement arrangements. This effort's major result is a useful genetic algorithm-based approach to assist in the discrete actuator/effector placement problem.
Approaches for Subgrid Parameterization: Does Scaling Help?
NASA Astrophysics Data System (ADS)
Yano, Jun-Ichi
2016-04-01
Arguably the scaling behavior is a well-established fact in many geophysical systems. There are already many theoretical studies elucidating this issue. However, the scaling law is slow to be introduced in "operational" geophysical modelling, notably for weather forecast as well as climate projection models. The main purpose of this presentation is to ask why, and try to answer this question. As a reference point, the presentation reviews the three major approaches for traditional subgrid parameterization: moment, PDF (probability density function), and mode decomposition. The moment expansion is a standard method for describing the subgrid-scale turbulent flows both in the atmosphere and the oceans. The PDF approach is intuitively appealing as it directly deals with a distribution of variables in subgrid scale in a more direct manner. The third category, originally proposed by Aubry et al (1988) in context of the wall boundary-layer turbulence, is specifically designed to represent coherencies in compact manner by a low--dimensional dynamical system. Their original proposal adopts the proper orthogonal decomposition (POD, or empirical orthogonal functions, EOF) as their mode-decomposition basis. However, the methodology can easily be generalized into any decomposition basis. The mass-flux formulation that is currently adopted in majority of atmospheric models for parameterizing convection can also be considered a special case of the mode decomposition, adopting the segmentally-constant modes for the expansion basis. The mode decomposition can, furthermore, be re-interpreted as a type of Galarkin approach for numerically modelling the subgrid-scale processes. Simple extrapolation of this re-interpretation further suggests us that the subgrid parameterization problem may be re-interpreted as a type of mesh-refinement problem in numerical modelling. We furthermore see a link between the subgrid parameterization and downscaling problems along this line. The mode decomposition approach would also be the best framework for linking between the traditional parameterizations and the scaling perspectives. However, by seeing the link more clearly, we also see strength and weakness of introducing the scaling perspectives into parameterizations. Any diagnosis under a mode decomposition would immediately reveal a power-law nature of the spectrum. However, exploiting this knowledge in operational parameterization would be a different story. It is symbolic to realize that POD studies have been focusing on representing the largest-scale coherency within a grid box under a high truncation. This problem is already hard enough. Looking at differently, the scaling law is a very concise manner for characterizing many subgrid-scale variabilities in systems. We may even argue that the scaling law can provide almost complete subgrid-scale information in order to construct a parameterization, but with a major missing link: its amplitude must be specified by an additional condition. The condition called "closure" in the parameterization problem, and known to be a tough problem. We should also realize that the studies of the scaling behavior tend to be statistical in the sense that it hardly provides complete information for constructing a parameterization: can we specify the coefficients of all the decomposition modes by a scaling law perfectly when the first few leading modes are specified? Arguably, the renormalization group (RNG) is a very powerful tool for reducing a system with a scaling behavior into a low dimension, say, under an appropriate mode decomposition procedure. However, RNG is analytical tool: it is extremely hard to apply it to real complex geophysical systems. It appears that it is still a long way to go for us before we can begin to exploit the scaling law in order to construct operational subgrid parameterizations in effective manner.
Sorting signed permutations by short operations.
Galvão, Gustavo Rodrigues; Lee, Orlando; Dias, Zanoni
2015-01-01
During evolution, global mutations may alter the order and the orientation of the genes in a genome. Such mutations are referred to as rearrangement events, or simply operations. In unichromosomal genomes, the most common operations are reversals, which are responsible for reversing the order and orientation of a sequence of genes, and transpositions, which are responsible for switching the location of two contiguous portions of a genome. The problem of computing the minimum sequence of operations that transforms one genome into another - which is equivalent to the problem of sorting a permutation into the identity permutation - is a well-studied problem that finds application in comparative genomics. There are a number of works concerning this problem in the literature, but they generally do not take into account the length of the operations (i.e. the number of genes affected by the operations). Since it has been observed that short operations are prevalent in the evolution of some species, algorithms that efficiently solve this problem in the special case of short operations are of interest. In this paper, we investigate the problem of sorting a signed permutation by short operations. More precisely, we study four flavors of this problem: (i) the problem of sorting a signed permutation by reversals of length at most 2; (ii) the problem of sorting a signed permutation by reversals of length at most 3; (iii) the problem of sorting a signed permutation by reversals and transpositions of length at most 2; and (iv) the problem of sorting a signed permutation by reversals and transpositions of length at most 3. We present polynomial-time solutions for problems (i) and (iii), a 5-approximation for problem (ii), and a 3-approximation for problem (iv). Moreover, we show that the expected approximation ratio of the 5-approximation algorithm is not greater than 3 for random signed permutations with more than 12 elements. Finally, we present experimental results that show that the approximation ratios of the approximation algorithms cannot be smaller than 3. In particular, this means that the approximation ratio of the 3-approximation algorithm is tight.
Automated Long - Term Scheduling for the SOFIA Airborne Observatory
NASA Technical Reports Server (NTRS)
Civeit, Thomas
2013-01-01
The NASA Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint US/German project to develop and operate a gyro-stabilized 2.5-meter telescope in a Boeing 747SP. SOFIA's first science observations were made in December 2010. During 2011, SOFIA accomplished 30 flights in the "Early Science" program as well as a deployment to Germany. The new observing period, known as Cycle 1, is scheduled to begin in 2012. It includes 46 science flights grouped in four multi-week observing campaigns spread through a 13-month span. Automation of the flight scheduling process offers a major challenge to the SOFIA mission operations. First because it is needed to mitigate its relatively high cost per unit observing time compared to space-borne missions. Second because automated scheduling techniques available for ground-based and space-based telescopes are inappropriate for an airborne observatory. Although serious attempts have been made in the past to solve part of the problem, until recently mission operations staff was still manually scheduling flights. We present in this paper a new automated solution for generating SOFIA long-term schedules that will be used in operations from the Cycle 1 observing period. We describe the constraints that should be satisfied to solve the SOFIA scheduling problem in the context of real operations. We establish key formulas required to efficiently calculate the aircraft course over ground when evaluating flight schedules. We describe the foundations of the SOFIA long-term scheduler, the constraint representation, and the random search based algorithm that generates observation and instrument schedules. Finally, we report on how the new long-term scheduler has been used in operations to date.
Axillary breast: Navigating uncharted terrain
Bhave, Medha A
2015-01-01
Introduction: Axillary breast is a common condition that leads to discomfort and cosmetic problems. Liposuction alone and open excision are two techniques used for treatment. Materials and Methods: This study assesses the results of treatment in 24 consecutive patients, operated between 2005 and 2015. All patients had Kajava class IV masses. Three were treated by liposuction alone, while 21 were treated by open axillaplasty with limited liposuction. Results: One patient treated by liposuction alone had to be re-operated for a residual lump, while with axillaplasty, no major complications were observed and the results were uniformly good. Discussion: Certain points of technique emerged as major determinants in obtaining the best results. In brief, these are: a) limited skin excision; b) placing elliptical incisions within the most lax, apical axillary skin, irrespective of the location of the lump; c) raising skin flaps at the level of superficial fascia; d)meticulous dissection and preservation of the nerves, especially the second intercostobrachial; f) judicious liposuction for eliminating dog ears and axillary sculpting only; g) avoiding drains. Conclusion: Open axillaplasty with limited liposuction is the best way to minimise complications and produce good results. PMID:26933282
Applications of nuclear power to lunar and Mars missions
NASA Technical Reports Server (NTRS)
Friedlander, Alan; Cole, Kevin
1988-01-01
The initial elements of an ambitious program for human exploration beyond Earth have been developed and presented to NASA management for its consideration. The Outpost on the Moon and Humans to Mars are two key U.S. programs (Ride 1987). A major space goal of this magnitude can only be implemented by a series of program phases evolving from precursor robotic missions, to initial development of temporary surface stations and buildup of operational experience, through the eventual establishment of permanent and sustained surface bases. Each phase of the separate (or linked) lunar and Mars scenarios will require distinctly different levels and types of power sources to support both transportation and on-surface operations, i.e., the nuclear power reactor. Discussed are the respective types and specific amounts of power required for all major systems in a phased program of lunar and Mars exploration over the period 1990 to 2040. A comparative assessment of technology tradeoffs and special design problems is made to ascertain the most appropriate application for the different phases, as well as to identify synergistic developments across the programs.
Rosenbaum, Sara
2015-02-01
Both before and after the Affordable Care Act (ACA), the US health insurance system is characterized by fragmentation. Pre-ACA, this fragmentation included major coverage gaps, causing significant periods of coverage interruption, especially for lower-income people. The ACA does not end the problem of churning among sources of public financing, but it does hold the potential for enabling people to move among sources of coverage rather than go without insurance. Several strategies for reducing coverage churn exist, but none is foolproof and all are in their early stages. Thus the ability of issuers to participate across multiple public financing arrangements and to offer stable provider networks becomes crucial to achieving continuity of care. Interviews with nine companies involved in developing or operating multimarket strategies confirm the feasibility of this approach while revealing major challenges, especially the challenge of finding providers willing to treat members regardless of the source of coverage. Strategies for increasing multimarket plans and networks represent one of the great areas of future policy and operational focus. Copyright © 2015 by Duke University Press.
Rasmussen, S; Kehlet, H
2007-09-01
Chronic neuropathic pain after leg amputation is a significant problem, with a reported incidence during the first year as high as 70%. Intra-operative handling of the nerves during amputation has not been discussed in the literature on post-amputation pain and, in major textbooks, it is recommended that the ischial nerve be ligated, despite the fact that the experimental literature uses nerve ligations to produce neuropathic pain. The purpose of this study was to investigate the clinical practice of nerve handling during leg amputation. Trainees with at least 2 years of practice received a questionnaire regarding handling of the nerves during leg amputation; 128 of 149 questionnaires sent (86%) were returned. Ligation of the nerves was used by 31% of surgeons. There is no consistency in the management of the large nerves during lower leg amputation. The recommendations in major textbooks may not be appropriate when compared with the experimental literature on nerve ligature models to produce neuropathic pain. Future studies on post-amputation pain should consider intra-operative nerve management.
NASA Technical Reports Server (NTRS)
Botteri, Benito P.
1987-01-01
During the past 15 years, very significant progress has been made toward enhancing aircraft fire safety in both normal and hostile (combat) operational environments. Most of the major aspects of the aircraft fire safety problem are touched upon here. The technology of aircraft fire protection, although not directly applicable in all cases to spacecraft fire scenarios, nevertheless does provide a solid foundation to build upon. This is particularly true of the extensive research and testing pertaining to aircraft interior fire safety and to onboard inert gas generation systems, both of which are still active areas of investigation.
Dynamical basis sets for algebraic variational calculations in quantum-mechanical scattering theory
NASA Technical Reports Server (NTRS)
Sun, Yan; Kouri, Donald J.; Truhlar, Donald G.; Schwenke, David W.
1990-01-01
New basis sets are proposed for linear algebraic variational calculations of transition amplitudes in quantum-mechanical scattering problems. These basis sets are hybrids of those that yield the Kohn variational principle (KVP) and those that yield the generalized Newton variational principle (GNVP) when substituted in Schlessinger's stationary expression for the T operator. Trial calculations show that efficiencies almost as great as that of the GNVP and much greater than the KVP can be obtained, even for basis sets with the majority of the members independent of energy.
New Opportunities for the Management and Therapy of Hepatitis C in Correctional Settings
Hostetter, Jeffrey E.; Hagan, John J.
2010-01-01
Hepatitis C in prison populations is now a major public health problem, and large numbers of correctional facilities have no comprehensive management program, often because of formidable projected costs and tightening budget constraints. The North Dakota Department of Corrections and Rehabilitation has operated a management and therapy program since 2002 using consensus interferon and ribavirin with 45% cost savings. The program has provided excellent sustained viral responses: 54.2% for genotype 1 hepatitis C, 75% for genotypes 2 and 3, and 63.6% overall. PMID:20007626
NASA Astrophysics Data System (ADS)
Harmanpreet, Singh, Sukhwinder; Kumar, Ashok; Kaur, Parneet
2010-11-01
Stability & security are main aspects in electrical power systems. Transformer protection is major issue of concern to system operation. There are many mall-trip cases of transformer protection are caused by inrush current problems. The phenomenon of transformer inrush current has been discussed in many papers since 1958. In this paper analytical analysis of inrush current in a transformer switched on dc and ac supply has been done. This analysis will help in design aspects of circuit breakers for better performance.
Silicon crystal growth in vacuum
NASA Technical Reports Server (NTRS)
Khattak, C. P.; Schmid, F.
1982-01-01
The most developed process for silicon crystal growth is the Czochralski (CZ) method which was in production for over two decades. In an effort to reduce cost of single crystal silicon for photovoltaic applications, a directional solidification technique, Heat Exchanger Method (HEM), was adapted. Materials used in HEM and CZ furnaces are quite similar (heaters, crucibles, insulation, etc.). To eliminate the cost of high purity argon, it was intended to use vacuum operation in HEM. Two of the major problems encountered in vacuum processing of silicon are crucible decomposition and silicon carbide formation in the melt.
Performance analysis and simulation of the SPS reference phase control system
NASA Technical Reports Server (NTRS)
Lindsey, W. C.; Chie, C. M.
1980-01-01
The major elements required in the operation of an SPS which employs retrodirectivity as a means of pointing the beam to Earth include the spacetenna, the rectenna, and the pilot signal transmitter. The phase control system is faced with several problems: (1) path delay variations due to imperfect SPS circular orbits; (2) ionospheric effects; (3) initial phase beam forming; (4) beam pointing; (5) beam safing; (6) high power phase noise effects; and (7) interference. The use of SOLARISM, a computer program to select pilot signal parameters and evaluate SPS performance is described.
Technology in the public schools?
NASA Technical Reports Server (NTRS)
Lipman, D.
1973-01-01
An evaluation of the forces operating on the public schools which might influence their disposition toward the utilization of technology is presented. It is suggested that the wide-ranging technology and know-how generated by the Federally sponsored research and development programs can be adapted and applied to the solution of problems found in education. It is suggested that three major developments in society have great bearing on the utilization of technology in educational programs. The extent to which these factors are manifested and interrelated, and the potential significance of their combined impact are analyzed.
1979-04-01
objective function, is not quite a linear programning problem. it is :71 converted to the strict linear programuing form by a dence due to Dantzig (31. We...than in Western Europe and Japan although the rapid rates of growth in air travel in both West Germany and Japan should be noted. Inter- city travel...second major issue in Canada is the impact of transport services on development and the rail freight rates that should be charged for services to and
Factors influencing aircraft ground handling performance
NASA Technical Reports Server (NTRS)
Yager, T. J.
1983-01-01
Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.
Liu, Chun; Kroll, Andreas
2016-01-01
Multi-robot task allocation determines the task sequence and distribution for a group of robots in multi-robot systems, which is one of constrained combinatorial optimization problems and more complex in case of cooperative tasks because they introduce additional spatial and temporal constraints. To solve multi-robot task allocation problems with cooperative tasks efficiently, a subpopulation-based genetic algorithm, a crossover-free genetic algorithm employing mutation operators and elitism selection in each subpopulation, is developed in this paper. Moreover, the impact of mutation operators (swap, insertion, inversion, displacement, and their various combinations) is analyzed when solving several industrial plant inspection problems. The experimental results show that: (1) the proposed genetic algorithm can obtain better solutions than the tested binary tournament genetic algorithm with partially mapped crossover; (2) inversion mutation performs better than other tested mutation operators when solving problems without cooperative tasks, and the swap-inversion combination performs better than other tested mutation operators/combinations when solving problems with cooperative tasks. As it is difficult to produce all desired effects with a single mutation operator, using multiple mutation operators (including both inversion and swap) is suggested when solving similar combinatorial optimization problems.
Complex fuzzy soft expert sets
NASA Astrophysics Data System (ADS)
Selvachandran, Ganeshsree; Hafeed, Nisren A.; Salleh, Abdul Razak
2017-04-01
Complex fuzzy sets and its accompanying theory although at its infancy, has proven to be superior to classical type-1 fuzzy sets, due its ability in representing time-periodic problem parameters and capturing the seasonality of the fuzziness that exists in the elements of a set. These are important characteristics that are pervasive in most real world problems. However, there are two major problems that are inherent in complex fuzzy sets: it lacks a sufficient parameterization tool and it does not have a mechanism to validate the values assigned to the membership functions of the elements in a set. To overcome these problems, we propose the notion of complex fuzzy soft expert sets which is a hybrid model of complex fuzzy sets and soft expert sets. This model incorporates the advantages of complex fuzzy sets and soft sets, besides having the added advantage of allowing the users to know the opinion of all the experts in a single model without the need for any additional cumbersome operations. As such, this model effectively improves the accuracy of representation of problem parameters that are periodic in nature, besides having a higher level of computational efficiency compared to similar models in literature.
Mbembati, Naboth A; Mwangu, Mugwira; Muhondwa, Eustace P Y; Leshabari, Melkizedek M
2008-04-01
Muhimbili National Hospital (MNH), a teaching and national referral hospital, is undergoing major reforms to improve the quality of health care. We performed a retrospective descriptive study using a set of performance indicators for the surgical and laboratory services of MNH in years 2001 and 2002, to help monitor and evaluate the impact of reforms on the quality of health care during and after the reform process. Hospital records were reviewed and information recorded for planned and postponed operations, laboratory equipment, reagents, laboratory tests and quality assurance programmes. In the year 2001 a total of 4332 non-emergency operations were planned, 3313 operations were performed and 1019 (23.5%) operations were postponed. In the year 2002, 4301 non-emergency operations were planned, 3046 were performed and 1255 (29%) were postponed. The most common reasons for operation postponement were "time-barred", interference by emergency operations, no show of patients and inoperable anaesthetic machines. Equipment problems and supply and staff shortages together accounted for one quarter of postponements. In the laboratory, a lack of equipment prevented some tests, but quality assurance was performed for most tests. Current surgical services at MNH are inadequate; operating theatres require modern, functioning equipment and adequate supplies of consumables to provide satisfactory care.
Work stress of women in sewing machine operation.
Nag, A; Desai, H; Nag, P K
1992-06-01
The study examined the work stresses of 107 women who were engaged in sewing machine operation in small garment manufacturing units. Of the three types of sewing machines (motor-operated, full and half shuttle foot-operated), 74% of the machines were foot-operated, where throttle action of the lower limb is required to move the shuttle of the machine. The motor-operated machines were faster than the foot-operated machines. The short cycle sewing work involves repetitive action of hand and feet. The women had to maintain a constant seated position on a stool without backrest and the body inclined forward. Long-term sewing work had a cumulative load on the musculo-skeletal structures, including the vertebral column and reflected in the form of high prevalence of discomfort and pain in different body parts. About 68% of the women complained of back pain, among whom 35% reported a persistent low back pain. Common sewing work accident is piercing of the needle through the fingers, particularly the right forefingers. Unsatisfactory man-machine incompatibility, work posture and fatigue, improper coordination of eye, leg and hand are the major problems of the operators. The design mis-match of the work place may be significantly improved by taking women's anthropometric dimensions in modifying the workplace, i.e. the seat surface, seat height, work height, backrest, etc.
The 1980 Aircraft Safety and Operating Problems, Part 2
NASA Technical Reports Server (NTRS)
Stickle, J. W. (Compiler)
1981-01-01
Terminal area operations, avionics and human factors, atmospheric environment, and operating problems and potential solutions are discussed. Other topics include flight experiences, ground operations, and acoustics and noise reduction.
Deployer Performance Results for the TSS-1 Mission
NASA Technical Reports Server (NTRS)
Marshall, Leland S.; Geiger, Ronald V.
1995-01-01
Performance of the Tethered Satellite System (TSS) Deployer during the STS-46 mission (July and August 1992) is analyzed in terms of hardware operation at the component and system level. Although only a limited deployment of the satellite was achieved (256 meters vs 20 kilometers planned), the mission served to verify the basic capability of the Deployer to release, control and retrieve a tethered satellite. - Deployer operational flexibility that was demonstrated during the flight is also addressed. Martin Marietta was the prime contractor for the development of the Deployer, under management of the NASA George C. Marshall Space Flight Center (MSFC). The satellite was provided by Alenia, Torino, Italy under contract to the Agencia Spaziale Italiana (ASI). Proper operation of the avionics components and the majority of mechanisms was observed during the flight. System operations driven by control laws for the deployment and retrieval of the satellite were also successful for the limited deployment distance. Anomalies included separation problems for one of the two umbilical connectors between the Deployer and satellite, tether jamming (at initial Satellite fly-away and at a deployment distance of 224 meters), and a mechanical interference which prevented tether deployment beyond 256 meters. The Deployer was used in several off-nominal conditions to respond to these anomalies, which ultimately enabled a successful satellite retrieval and preservation of hardware integrity for a future re-flight. The paper begins with an introduction defining the significance of the TSS-1 mission. The body of the paper is divided into four major sections: (1) Description of Deployer System and Components, (2) Deployer Components/Systems Demonstrating Successful Operation, (3) Hardware Anomalies and Operational Responses, and (4) Design Modifications for the TSS-1R Re-flight Mission. Conclusions from the TSS-1 mission, including lessons learned are presented at the end of the manuscript.
Application of Several Techniques for Prohibiting Fouling in Li-Recovery Pilot Plant
NASA Astrophysics Data System (ADS)
Yoon, H.; Kim, D.; Gong, M.; Kim, B.; Chung, K.
2010-12-01
The problem of marine organisms adhering to any surfaces exposed in seawater is as old as time. Marine fouling is a major problem in the materials used in seawater worldwide. Marine coatings contain elements such as copper and triorganotin compounds were often used as an effective compound for control the fouling problem, but application of such coatings containing triorganotin compounds was prohibited and the former are considered undesirable because of its toxicity and accumulative in non-target organisms. Monitoring and field studies regarding fouling problems during operation of Li-recovery pilot plant which is designed by the Korea Institute of Geoscience & Mineral Resources (KIGAM) were major concern of this study. Fouling could be the most troublesome tasks during the development of a large scale pilot production test for achieving a high performance adsorbent for seawater dissolved Li recovery. Chemical and microbiological characteristics of the fouling biofilms developed on various surfaces in contact with the seawater were made. The microbial compositions of the biofilm consortia formed on the reservoir polymer surfaces were also tested for. The quantities of the diverse microorganisms in the biofilm samples developed on the prohibiting polymer reservoir surface were larger when there was no concern about materials for special selection for fouling. The experimental results offered new specific information, concerning the problems in the application of new material as well as surface coating such as anti-fouling coatings. They showed the important role microbial activity in fouling and corrosion of the surfaces in contact with the any seawater. Acknowledgements: This research was supported by a grant from the Development of Technology for Extraction of Resources Dissolved in Sea Water Program funded by Ministry of Land Transport and Maritime Affairs in Korean Government (2010).
Benefits and problems of health-care robots in aged care settings: A comparison trial.
Broadbent, Elizabeth; Kerse, Ngaire; Peri, Kathryn; Robinson, Hayley; Jayawardena, Chandimal; Kuo, Tony; Datta, Chandan; Stafford, Rebecca; Butler, Haley; Jawalkar, Pratyusha; Amor, Maddy; Robins, Ben; MacDonald, Bruce
2016-03-01
This study investigated whether multiple health-care robots could have any benefits or cause any problems in an aged care facility. Fifty-three residents and 53 staff participated in a non-randomised controlled trial over 12 weeks. Six robots provided entertainment, communication and health-monitoring functions in staff rooms and activity lounges. These settings were compared to control settings without robots. There were no significant differences between groups in resident or staff outcomes, except a significant increase in job satisfaction in the control group only. The intervention group perceived the robots had more agency and experience than the control group did. Perceived agency of the robots decreased over time in both groups. Overall, we received very mixed responses with positive, neutral and negative comments. The robots had no major benefits or problems. Future research could give robots stronger operational roles, use more specific outcome measures, and perform cost-benefit analyses. © 2015 AJA Inc.
NASA Technical Reports Server (NTRS)
Ballard, RIchard O.
2006-01-01
This paper is a summary overview of a study conducted at the NASA Marshall Space Flight Center (NASA MSFC) during the initial phases of the Space Launch Initiative (SLI) program to evaluate a large number of technical problems associated with the design, development, test, evaluation and operation of several major liquid propellant rocket engine systems (i.e., SSME, Fastrac, J-2, F-1). One of the primary results of this study was the identification of the Fundamental Root Causes that enabled the technical problems to manifest, and practices that can be implemented to prevent them from recurring in future propulsion system development efforts, such as that which is currently envisioned in the field of nuclear thermal propulsion (NTF). This paper will discuss the Fundamental Root Causes, cite some examples of how the technical problems arose from them, and provide a discussion of how they can be mitigated or avoided in the development of an NTP system
Gambling in Finland: problem gambling in the context of a national monopoly in the European Union.
Tammi, Tuukka; Castrén, Sari; Lintonen, Tomi
2015-05-01
To describe and analyse the Finnish gambling market, regulatory system and the state of gambling research as well as the treatment system in operation for problem gamblers. A review of the literature and official documents relating to gambling in Finland, focusing primarily on the 1990s and 2000s. Only in recent years have gambling problems become a major issue for public debate in Finland. One reason for the increase in activity to address gambling problems is that, after Finland became a member of the European Union in 1995, the Finnish state gambling monopoly and its compatibility with European Union (EU) regulations have been questioned repeatedly. Since 2000, the Finnish government has put significant new resources into the research as well as the prevention and treatment of gambling problems. The resources grew from almost nothing to several million Euros in less than 10 years. This could be seen as an attempt to protect the national gambling monopoly system by showing that the Finnish monopoly system meets EU requirements. Since joining the European Union in 1995, the Finnish government has been able to maintain its gambling monopoly by providing substantial resources to signal a commitment to minimizing problem gambling. © 2015 Society for the Study of Addiction.
Image restoration by the method of convex projections: part 1 theory.
Youla, D C; Webb, H
1982-01-01
A projection operator onto a closed convex set in Hilbert space is one of the few examples of a nonlinear map that can be defined in simple abstract terms. Moreover, it minimizes distance and is nonexpansive, and therefore shares two of the more important properties of ordinary linear orthogonal projections onto closed linear manifolds. In this paper, we exploit the properties of these operators to develop several iterative algorithms for image restoration from partial data which permit any number of nonlinear constraints of a certain type to be subsumed automatically. Their common conceptual basis is as follows. Every known property of an original image f is envisaged as restricting it to lie in a well-defined closed convex set. Thus, m such properties place f in the intersection E(0) = E(i) of the corresponding closed convex sets E(1),E(2),...EE(m). Given only the projection operators PE(i) onto the individual E(i)'s, i = 1 --> m, we restore f by recursive means. Clearly, in this approach, the realization of the P(i)'s in a Hilbert space setting is one of the major synthesis problems. Section I describes the geometrical significance of the three main theorems in considerable detail, and most of the underlying ideas are illustrated with the aid of simple diagrams. Section II presents rules for the numerical implementation of 11 specific projection operators which are found to occur frequently in many signal-processing applications, and the Appendix contains proofs of all the major results.
NASA Astrophysics Data System (ADS)
Habtu, Solomon; Ludi, Eva; Jamin, Jean Yves; Oates, Naomi; Fissahaye Yohannes, Degol
2014-05-01
Practicing various innovations pertinent to irrigated farming at local field scale is instrumental to increase productivity and yield for small holder farmers in Africa. However the translation of innovations from local scale to the scale of a jointly operated irrigation scheme is far from trivial. It requires insight on the drivers for adoption of local innovations within the wider farmer communities. Participatory methods are expected to improve not only the acceptance of locally developed innovations within the wider farmer communities, but to allow also an estimation to which extend changes will occur within the entire irrigation scheme. On such a base, more realistic scenarios of future water productivity within an irrigation scheme, which is operated by small holder farmers, can be estimated. Initial participatory problem and innovation appraisal was conducted in Gumselassa small scale irrigation scheme, Ethiopia, from Feb 27 to March 3, 2012 as part of the EAU4FOOD project funded by EC. The objective was to identify and appraise problems which hinder sustainable water management to enhance production and productivity and to identify future research strategies. Workshops were conducted both at local (Community of Practices) and regional (Learning Practice Alliance) level. At local levels, intensive collaboration with farmers using participatory methods produced problem trees and a "Photo Safari" documented a range of problems that negatively impact on productive irrigated farming. A range of participatory methods were also used to identify local innovations. At regional level a Learning Platform was established that includes a wide range of stakeholders (technical experts from various government ministries, policy makers, farmers, extension agents, researchers). This stakeholder group did a range of exercise as well to identify major problems related to irrigated smallholder farming and already identified innovations. Both groups identified similar problems to productive smallholder irrigation: soil nutrient depletion, salinization, disease and pest resulting from inefficient irrigation practices, infrastructure problems leading to a reduction of the size of the command area and decrease in reservoir volume. The major causes have been poor irrigation infrastructure, poor on-farm soil and water management, prevalence of various crop pests and diseases, lack of inputs and reservoir siltation. On-farm participatory research focusing on soil, crop and water management issues, including technical, institutional and managerial aspects, to identify best performing innovations while taking care of the environment was recommended. Currently, a range of interlinked activities are implemented a multiple scales, combining participatory and scientific approaches towards innovation development and up-scaling of promising technologies and institutional and managerial approaches from local to regional scales. ____________________________ Key words: Irrigation scheme, productivity, innovation, participatory method, Gumselassa, Ethiopia
Tuomisto, Jouni T; Tainio, Marko
2005-01-01
Background Traffic congestion is rapidly becoming the most important obstacle to urban development. In addition, traffic creates major health, environmental, and economical problems. Nonetheless, automobiles are crucial for the functions of the modern society. Most proposals for sustainable traffic solutions face major political opposition, economical consequences, or technical problems. Methods We performed a decision analysis in a poorly studied area, trip aggregation, and studied decisions from the perspective of two different stakeholders, the passenger and society. We modelled the impact and potential of composite traffic, a hypothetical large-scale demand-responsive public transport system for the Helsinki metropolitan area, where a centralised system would collect the information on all trip demands online, would merge the trips with the same origin and destination into public vehicles with eight or four seats, and then would transmit the trip instructions to the passengers' mobile phones. Results We show here that in an urban area with one million inhabitants, trip aggregation could reduce the health, environmental, and other detrimental impacts of car traffic typically by 50–70%, and if implemented could attract about half of the car passengers, and within a broad operational range would require no public subsidies. Conclusion Composite traffic provides new degrees of freedom in urban decision-making in identifying novel solutions to the problems of urban traffic. PMID:16309549
A Cognitive Simulator for Learning the Nature of Human Problem Solving
NASA Astrophysics Data System (ADS)
Miwa, Kazuhisa
Problem solving is understood as a process through which states of problem solving are transferred from the initial state to the goal state by applying adequate operators. Within this framework, knowledge and strategies are given as operators for the search. One of the most important points of researchers' interest in the domain of problem solving is to explain the performance of problem solving behavior based on the knowledge and strategies that the problem solver has. We call the interplay between problem solvers' knowledge/strategies and their behavior the causal relation between mental operations and behavior. It is crucially important, we believe, for novice learners in this domain to understand the causal relation between mental operations and behavior. Based on this insight, we have constructed a learning system in which learners can control mental operations of a computational agent that solves a task, such as knowledge, heuristics, and cognitive capacity, and can observe its behavior. We also introduce this system to a university class, and discuss which findings were discovered by the participants.
Multigrid methods for differential equations with highly oscillatory coefficients
NASA Technical Reports Server (NTRS)
Engquist, Bjorn; Luo, Erding
1993-01-01
New coarse grid multigrid operators for problems with highly oscillatory coefficients are developed. These types of operators are necessary when the characters of the differential equations on coarser grids or longer wavelengths are different from that on the fine grid. Elliptic problems for composite materials and different classes of hyperbolic problems are practical examples. The new coarse grid operators can be constructed directly based on the homogenized differential operators or hierarchically computed from the finest grid. Convergence analysis based on the homogenization theory is given for elliptic problems with periodic coefficients and some hyperbolic problems. These are classes of equations for which there exists a fairly complete theory for the interaction between shorter and longer wavelengths in the problems. Numerical examples are presented.
Mathematical Problem Solving: A Review of the Literature.
ERIC Educational Resources Information Center
Funkhouser, Charles
The major perspectives on problem solving of the twentieth century are reviewed--associationism, Gestalt psychology, and cognitive science. The results of the review on teaching problem solving and the uses of computers to teach problem solving are included. Four major issues related to the teaching of problem solving are discussed: (1)…
2007 SB14 Source Reduction Plan/Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, L
2007-07-24
Aqueous solutions (mixed waste) generated from various LLNL operations, such as debris washing, sample preparation and analysis, and equipment maintenance and cleanout, were combined for storage in the B695 tank farm. Prior to combination the individual waste streams had different codes depending on the particular generating process and waste characteristics. The largest streams were CWC 132, 791, 134, 792. Several smaller waste streams were also included. This combined waste stream was treated at LLNL's waste treatment facility using a vacuum filtration and cool vapor evaporation process in preparation for discharge to sanitary sewer. Prior to discharge, the treated waste streammore » was sampled and the results were reviewed by LLNL's water monitoring specialists. The treated solution was discharged following confirmation that it met the discharge criteria. A major source, accounting for 50% for this waste stream, is metal machining, cutting and grinding operations in the engineering machine shops in B321/B131. An additional 7% was from similar operations in B131 and B132S. This waste stream primarily contains metal cuttings from machined parts, machining coolant and water, with small amounts of tramp oil from the machining and grinding equipment. Several waste reduction measures for the B321 machine shop have been taken, including the use of a small point-of-use filtering/tramp-oil coalescing/UV-sterilization coolant recycling unit, and improved management techniques (testing and replenishing) for coolants. The recycling unit had some operational problems during 2006. The machine shop is planning to have it repaired in the near future. A major source, accounting for 50% for this waste stream, is metal machining, cutting and grinding operations in the engineering machine shops in B321/B131. An additional 7% was from similar operations in B131 and B132S. This waste stream primarily contains metal cuttings from machined parts, machining coolant and water, with small amounts of tramp oil from the machining and grinding equipment. Several waste reduction measures for the B321 machine shop have been taken, including the use of a small point-of-use filtering/tramp-oil coalescing/UV-sterilization coolant recycling unit, and improved management techniques (testing and replenishing) for coolants. The recycling unit had some operational problems during 2006. The machine shop is planning to have it repaired in the near future. Quarterly waste generation data prepared by the Environmental Protection Department's P2 Team are regularly provided to engineering shops as well as other facilities so that generators can track the effectiveness of their waste minimization efforts.« less
General aviation IFR operational problems
NASA Technical Reports Server (NTRS)
Bolz, E. H.; Eisele, J. E.
1979-01-01
Operational problems of general aviation IFR operators (particularly single pilot operators) were studied. Several statistical bases were assembled and utilized to identify the more serious problems and to demonstrate their magnitude. These bases include official activity projections, historical accident data and delay data, among others. The GA operating environment and cockpit environment were analyzed in detail. Solutions proposed for each of the problem areas identified are based on direct consideration of currently planned enhancements to the ATC system, and on a realistic assessment of the present and future limitations of general aviation avionics. A coordinated set of research program is suggested which would provide the developments necessary to implement the proposed solutions.
NASA Technical Reports Server (NTRS)
Zanley, Nancy L.
1991-01-01
The NASA Science Internet (NSI) Network Operations Staff is responsible for providing reliable communication connectivity for the NASA science community. As the NSI user community expands, so does the demand for greater interoperability with users and resources on other networks (e.g., NSFnet, ESnet), both nationally and internationally. Coupled with the science community's demand for greater access to other resources is the demand for more reliable communication connectivity. Recognizing this, the NASA Science Internet Project Office (NSIPO) expands its Operations activities. By January 1990, Network Operations was equipped with a telephone hotline, and its staff was expanded to six Network Operations Analysts. These six analysts provide 24-hour-a-day, 7-day-a-week coverage to assist site managers with problem determination and resolution. The NSI Operations staff monitors network circuits and their associated routers. In most instances, NSI Operations diagnoses and reports problems before users realize a problem exists. Monitoring of the NSI TCP/IP Network is currently being done with Proteon's Overview monitoring system. The Overview monitoring system displays a map of the NSI network utilizing various colors to indicate the conditions of the components being monitored. Each node or site is polled via the Simple Network Monitoring Protocol (SNMP). If a circuit goes down, Overview alerts the Network Operations staff with an audible alarm and changes the color of the component. When an alert is received, Network Operations personnel immediately verify and diagnose the problem, coordinate repair with other networking service groups, track problems, and document problem and resolution into a trouble ticket data base. NSI Operations offers the NSI science community reliable connectivity by exercising prompt assessment and resolution of network problems.
Automatic Combination of Operators in a Genetic Algorithm to Solve the Traveling Salesman Problem.
Contreras-Bolton, Carlos; Parada, Victor
2015-01-01
Genetic algorithms are powerful search methods inspired by Darwinian evolution. To date, they have been applied to the solution of many optimization problems because of the easy use of their properties and their robustness in finding good solutions to difficult problems. The good operation of genetic algorithms is due in part to its two main variation operators, namely, crossover and mutation operators. Typically, in the literature, we find the use of a single crossover and mutation operator. However, there are studies that have shown that using multi-operators produces synergy and that the operators are mutually complementary. Using multi-operators is not a simple task because which operators to use and how to combine them must be determined, which in itself is an optimization problem. In this paper, it is proposed that the task of exploring the different combinations of the crossover and mutation operators can be carried out by evolutionary computing. The crossover and mutation operators used are those typically used for solving the traveling salesman problem. The process of searching for good combinations was effective, yielding appropriate and synergic combinations of the crossover and mutation operators. The numerical results show that the use of the combination of operators obtained by evolutionary computing is better than the use of a single operator and the use of multi-operators combined in the standard way. The results were also better than those of the last operators reported in the literature.
Automatic Combination of Operators in a Genetic Algorithm to Solve the Traveling Salesman Problem
2015-01-01
Genetic algorithms are powerful search methods inspired by Darwinian evolution. To date, they have been applied to the solution of many optimization problems because of the easy use of their properties and their robustness in finding good solutions to difficult problems. The good operation of genetic algorithms is due in part to its two main variation operators, namely, crossover and mutation operators. Typically, in the literature, we find the use of a single crossover and mutation operator. However, there are studies that have shown that using multi-operators produces synergy and that the operators are mutually complementary. Using multi-operators is not a simple task because which operators to use and how to combine them must be determined, which in itself is an optimization problem. In this paper, it is proposed that the task of exploring the different combinations of the crossover and mutation operators can be carried out by evolutionary computing. The crossover and mutation operators used are those typically used for solving the traveling salesman problem. The process of searching for good combinations was effective, yielding appropriate and synergic combinations of the crossover and mutation operators. The numerical results show that the use of the combination of operators obtained by evolutionary computing is better than the use of a single operator and the use of multi-operators combined in the standard way. The results were also better than those of the last operators reported in the literature. PMID:26367182
Environmental and health impact assessment for ports in Thailand.
Chanchang, Chamchan; Sithisarankul, Pornchai; Supanitayanon, Thanawat
2016-01-01
Port development in Thailand is an essential part of the national maritime interest in connection with ship and shore activities. The growth of maritime industry and transportation has led to the expansion of ports' areas and capacity. Each port type causes different environmental impacts. Therefore, the Port Authority of Thailand has set up guidelines on ports' environmental management. This is divided into 3 major phases; namely, planning, construction and operation commencement periods. The Report of Environmental and Health Impact Assessment (EIA, HIA and EHIA) is regarded as the environmental management process in the planning period. It is a key tool to anticipate and prevent any adverse effects that might occur on the environment as well as community health resulting from the project implementation. This measure, in turn, creates advance preparation on both the preventive and problem-solving means before the project gets off the ground. At present, the majority of new projects on port development have still been in the process of information gathering for EHIA submission. Some cannot start to operate due to their EHIA failure. For example, the Tha-sala port which did not pass EHIA, mainly because emphasis had been focused on adhering to legal regulations without taking into consideration the in-depth analysis of data being conducted by community entities in the area. Thus caused the project to be finally abolished. Impact assessment on environment and health should be aimed at detailed understanding of the community in each particular area so that effective data of objective achievement in preventing environmental problems could actually be carried out and welcomed by the concerned society.
A Successful Senior Seminar: Unsolved Problems in Number Theory
ERIC Educational Resources Information Center
Styer, Robert
2014-01-01
The "Unsolved Problems in Number Theory" book by Richard Guy provides nice problems suitable for a typical math major. We give examples of problems that have worked well in our senior seminar course and some nice results that senior math majors can obtain.
Research on Scheduling Algorithm for Multi-satellite and Point Target Task on Swinging Mode
NASA Astrophysics Data System (ADS)
Wang, M.; Dai, G.; Peng, L.; Song, Z.; Chen, G.
2012-12-01
Nowadays, using satellite in space to observe ground is an important and major method to obtain ground information. With the development of the scientific technology in the field of space, many fields such as military and economic and other areas have more and more requirement of space technology because of the benefits of the satellite's widespread, timeliness and unlimited of area and country. And at the same time, because of the wide use of all kinds of satellites, sensors, repeater satellites and ground receiving stations, ground control system are now facing great challenge. Therefore, how to make the best value of satellite resources so as to make full use of them becomes an important problem of ground control system. Satellite scheduling is to distribute the resource to all tasks without conflict to obtain the scheduling result so as to complete as many tasks as possible to meet user's requirement under considering the condition of the requirement of satellites, sensors and ground receiving stations. Considering the size of the task, we can divide tasks into point task and area task. This paper only considers point targets. In this paper, a description of satellite scheduling problem and a chief introduction of the theory of satellite scheduling are firstly made. We also analyze the restriction of resource and task in scheduling satellites. The input and output flow of scheduling process are also chiefly described in the paper. On the basis of these analyses, we put forward a scheduling model named as multi-variable optimization model for multi-satellite and point target task on swinging mode. In the multi-variable optimization model, the scheduling problem is transformed the parametric optimization problem. The parameter we wish to optimize is the swinging angle of every time-window. In the view of the efficiency and accuracy, some important problems relating the satellite scheduling such as the angle relation between satellites and ground targets, positive and negative swinging angle and the computation of time window are analyzed and discussed. And many strategies to improve the efficiency of this model are also put forward. In order to solve the model, we bring forward the conception of activity sequence map. By using the activity sequence map, the activity choice and the start time of the activity can be divided. We also bring forward three neighborhood operators to search the result space. The front movement remaining time and the back movement remaining time are used to analyze the feasibility to generate solution from neighborhood operators. Lastly, the algorithm to solve the problem and model is put forward based genetic algorithm. Population initialization, crossover operator, mutation operator, individual evaluation, collision decrease operator, select operator and collision elimination operator is designed in the paper. Finally, the scheduling result and the simulation for a practical example on 5 satellites and 100 point targets with swinging mode is given, and the scheduling performances are also analyzed while the swinging angle in 0, 5, 10, 15, 25. It can be shown by the result that the model and the algorithm are more effective than those ones without swinging mode.
Adapting to Regional Enforcement: Fishing Down the Governance Index
Österblom, Henrik; Sumaila, U. Rashid; Bodin, Örjan; Hentati Sundberg, Jonas; Press, Anthony J.
2010-01-01
Background Illegal, Unreported and Unregulated (IUU) fishing is a problem for marine resource managers, leading to depletion of fish stocks and negative impacts on marine ecosystems. These problems are particularly evident in regions with weak governance. Countries responsible for sustainable natural resource management in the Southern Ocean have actively worked to reduce IUU fishing in the region over a period of 15 years, leading to a sequence of three distinct peaks of IUU fishing. Methodology/Principal Findings We reviewed existing public records relating to IUU fishing in the Southern Ocean between 1995–2009 and related this information to the governance capacity of flag states responsible for IUU vessels. IUU operators used a number of methods to adapt to enforcement actions, resulting in reduced risks of detection, apprehension and sanctioning. They changed fishing locations, vessel names and flag states, and ports for offloading IUU catches. There was a significant decrease in the proportion of IUU vessels flagged to CCAMLR countries, and a significant decrease in the average governance index of flag states. Despite a decreasing trend of IUU fishing, further actions are hampered by the regional scope of CCAMLR and the governance capacity of responsible states. Conclusions/Significance This is the first study of long-term change in the modus operandi of IUU fishing operators, illustrating that IUU operators can adapt to enforcement actions and that such dynamics may lead to new problems elsewhere, where countries have a limited capacity. This outsourcing of problems may have similarities to natural resource extraction in other sectors and in other regions. IUU fishing is the result of a number of factors, and effectively addressing this major challenge to sustainable marine resource extraction will likely require a stronger focus on governance. Highly mobile resource extractors with substantial funds are able to adapt to changing regulations by exploiting countries and regions with limited capacity. PMID:20877460
Free wake analysis of hover performance using a new influence coefficient method
NASA Technical Reports Server (NTRS)
Quackenbush, Todd R.; Bliss, Donald B.; Ong, Ching Cho; Ching, Cho Ong
1990-01-01
A new approach to the prediction of helicopter rotor performance using a free wake analysis was developed. This new method uses a relaxation process that does not suffer from the convergence problems associated with previous time marching simulations. This wake relaxation procedure was coupled to a vortex-lattice, lifting surface loads analysis to produce a novel, self contained performance prediction code: EHPIC (Evaluation of Helicopter Performance using Influence Coefficients). The major technical features of the EHPIC code are described and a substantial amount of background information on the capabilities and proper operation of the code is supplied. Sample problems were undertaken to demonstrate the robustness and flexibility of the basic approach. Also, a performance correlation study was carried out to establish the breadth of applicability of the code, with very favorable results.
The political economy of healthy system reform in Israel.
Chernichovsky, D; Chinitz, D
1995-01-01
On June 15, 1994, the Israeli Parliament voted to enact the National Health Insurance bill (NHI). The bill marks the end of a process that lasted for virtually as long as Israel's almost 50 year history. Israel's attempts at health reform began long before the current spate of reforms in many Western countries. Faced with many of the same problems of access, equity and cost control common to many of its counterparts, Israel initiated a reform process based on the recommendations of a prominent State Commission of Inquiry into the Israeli Health System (the Netanyahu Commission) which reported to the Government in 1990. The Commission's proposals were based on a diagnosis indicating that the major problems of the system stem from the lack of clarity regarding the rights of citizens to health care, the lack of a clear allocation of responsibility and accountability among government, insurance or sick funds, and providers in the system, and undue centralization of system operations. This diagnosis led to three major planks for reform: (1) enactment of national health insurance legislation granting a basic package of care to each citizen and hence bringing most of the system's finance under public auspices; (2) divesting the Government from the organization, management and provision of care; hence integrating the management of preventive and psychiatric services provided by the government with the primary and other services provided by sick funds, and granting financial and operational independence to at least government hospitals; and (3) restructuring the Ministry of Health. As is often the case in public policy, more consensus surrounds the diagnosis than the solutions. As a result, nearly four years of implementation efforts have only recently resulted in a major breakthrough. In this paper we make an effort to outline the inherent weaknesses of the Israeli health care system that have led to the crisis in the mid 1980s, summarize the recommendations of the State Commission for structural change in the system, and review the politics of implementing the recommended reforms.
IoT-based smart garbage system for efficient food waste management.
Hong, Insung; Park, Sunghoi; Lee, Beomseok; Lee, Jaekeun; Jeong, Daebeom; Park, Sehyun
2014-01-01
Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%.
IoT-Based Smart Garbage System for Efficient Food Waste Management
Lee, Jaekeun
2014-01-01
Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%. PMID:25258730
Spectral geometry of {kappa}-Minkowski space
DOE Office of Scientific and Technical Information (OSTI.GOV)
D'Andrea, Francesco
After recalling Snyder's idea [Phys. Rev. 71, 38 (1947)] of using vector fields over a smooth manifold as 'coordinates on a noncommutative space', we discuss a two-dimensional toy-model whose 'dual' noncommutative coordinates form a Lie algebra: this is the well-known {kappa}-Minkowski space [Phys. Lett. B 334, 348 (1994)]. We show how to improve Snyder's idea using the tools of quantum groups and noncommutative geometry. We find a natural representation of the coordinate algebra of {kappa}-Minkowski as linear operators on an Hilbert space (a major problem in the construction of a physical theory), study its 'spectral properties', and discuss how tomore » obtain a Dirac operator for this space. We describe two Dirac operators. The first is associated with a spectral triple. We prove that the cyclic integral of Dimitrijevic et al. [Eur. Phys. J. C 31, 129 (2003)] can be obtained as Dixmier trace associated to this triple. The second Dirac operator is equivariant for the action of the quantum Euclidean group, but it has unbounded commutators with the algebra.« less
Operator priming and generalization of practice in adults' simple arithmetic.
Chen, Yalin; Campbell, Jamie I D
2016-04-01
There is a renewed debate about whether educated adults solve simple addition problems (e.g., 2 + 3) by direct fact retrieval or by fast, automatic counting-based procedures. Recent research testing adults' simple addition and multiplication showed that a 150-ms preview of the operator (+ or ×) facilitated addition, but not multiplication, suggesting that a general addition procedure was primed by the + sign. In Experiment 1 (n = 36), we applied this operator-priming paradigm to rule-based problems (0 + N = N, 1 × N = N, 0 × N = 0) and 1 + N problems with N ranging from 0 to 9. For the rule-based problems, we found both operator-preview facilitation and generalization of practice (e.g., practicing 0 + 3 sped up unpracticed 0 + 8), the latter being a signature of procedure use; however, we also found operator-preview facilitation for 1 + N in the absence of generalization, which implies the 1 + N problems were solved by fact retrieval but nonetheless were facilitated by an operator preview. Thus, the operator preview effect does not discriminate procedure use from fact retrieval. Experiment 2 (n = 36) investigated whether a population with advanced mathematical training-engineering and computer science students-would show generalization of practice for nonrule-based simple addition problems (e.g., 1 + 4, 4 + 7). The 0 + N problems again presented generalization, whereas no nonzero problem type did; but all nonzero problems sped up when the identical problems were retested, as predicted by item-specific fact retrieval. The results pose a strong challenge to the generality of the proposal that skilled adults' simple addition is based on fast procedural algorithms, and instead support a fact-retrieval model of fast addition performance. (c) 2016 APA, all rights reserved).
Understanding and Counteracting Fatigue in Flight Crews
NASA Technical Reports Server (NTRS)
Mallis, Melissa; Neri, David; Rosekind, Mark; Gander, Philippa; Caldwell, John; Graeber, Curtis
2007-01-01
The materials included in the collection of documents describe the research of the NASA Ames Fatigue Countermeasures Group (FCG), which examines the extent to which fatigue, sleep loss, and circadian disruption affect flight-crew performance. The group was formed in 1980 in response to a Congressional request to examine a possible safety problem of uncertain magnitude due to transmeridian flying and a potential problem due to fatigue in association with various factors found in air-transport operations and was originally called the Fatigue/Jet Lag Program. The goals of the FCG are: (1) the development and evaluation of strategies for mitigating the effects of sleepiness and circadian disruption on pilot performance levels; (2) the identification and evaluation of objective approaches for the prediction of alertness changes in flight crews; and (3) the transfer and application of research results to the operational field via classes, workshops, and safety briefings. Some of the countermeasure approaches that have been identified to be scientifically valid and operationally relevant are brief naps (less than 40 min) in the cockpit seat and 7-min activity breaks, which include postural changes and ambulation. Although a video-based alertness monitor based on slow eyelid closure shows promise in other operational environments, research by the FCG has demonstrated that in its current form at the time of this reporting, it is not feasible to implement it in the cockpit. Efforts also focus on documenting the impact of untreated fatigue on various types of flight operations. For example, the FCG recently completed a major investigation into the effects of ultra-long-range flights (20 continuous hours in duration) on the alertness and performance of pilots in order to establish a baseline set of parameters against which the effectiveness of new ultra-long-range fatigue remedies can be judged.
SRM Internal Flow Test and Computational Fluid Dynamic Analysis. Volume 1; Major Task Summaries
NASA Technical Reports Server (NTRS)
Whitesides, R. Harold; Dill, Richard A.; Purinton, David C.
1995-01-01
During the four year period of performance for NASA contract, NASB-39095, ERC has performed a wide variety of tasks to support the design and continued development of new and existing solid rocket motors and the resolution of operational problems associated with existing solid rocket motor's at NASA MSFC. This report summarizes the support provided to NASA MSFC during the contractual period of performance. The report is divided into three main sections. The first section presents summaries for the major tasks performed. These tasks are grouped into three major categories: full scale motor analysis, subscale motor analysis and cold flow analysis. The second section includes summaries describing the computational fluid dynamics (CFD) tasks performed. The third section, the appendices of the report, presents detailed descriptions of the analysis efforts as well as published papers, memoranda and final reports associated with specific tasks. These appendices are referenced in the summaries. The subsection numbers for the three sections correspond to the same topics for direct cross referencing.
Insight and analysis problem solving in microbes to machines.
Clark, Kevin B
2015-11-01
A key feature for obtaining solutions to difficult problems, insight is oftentimes vaguely regarded as a special discontinuous intellectual process and/or a cognitive restructuring of problem representation or goal approach. However, this nearly century-old state of art devised by the Gestalt tradition to explain the non-analytical or non-trial-and-error, goal-seeking aptitude of primate mentality tends to neglect problem-solving capabilities of lower animal phyla, Kingdoms other than Animalia, and advancing smart computational technologies built from biological, artificial, and composite media. Attempting to provide an inclusive, precise definition of insight, two major criteria of insight, discontinuous processing and problem restructuring, are here reframed using terminology and statistical mechanical properties of computational complexity classes. Discontinuous processing becomes abrupt state transitions in algorithmic/heuristic outcomes or in types of algorithms/heuristics executed by agents using classical and/or quantum computational models. And problem restructuring becomes combinatorial reorganization of resources, problem-type substitution, and/or exchange of computational models. With insight bounded by computational complexity, humans, ciliated protozoa, and complex technological networks, for example, show insight when restructuring time requirements, combinatorial complexity, and problem type to solve polynomial and nondeterministic polynomial decision problems. Similar effects are expected from other problem types, supporting the idea that insight might be an epiphenomenon of analytical problem solving and consequently a larger information processing framework. Thus, this computational complexity definition of insight improves the power, external and internal validity, and reliability of operational parameters with which to classify, investigate, and produce the phenomenon for computational agents ranging from microbes to man-made devices. Copyright © 2015 Elsevier Ltd. All rights reserved.
Low-dose aspirin before spinal surgery: results of a survey among neurosurgeons in Germany.
Korinth, Marcus C; Gilsbach, Joachim M; Weinzierl, Martin R
2007-03-01
The main problem faced by the increasing numbers of patients presenting for spinal surgery are receiving concurrent medication with low-dose aspirin, leading to dysfunctional circulating platelets. The contribution of low-dose aspirin to increased peri-operative risk of bleeding and blood loss is a contentious issue with conflicting published results from different surgical groups. Data from neurosurgical spine patients is sparse, but aspirin has been identified as an important risk factor in the development of post-operative hematoma following intracranial surgery. We surveyed the opinions and working practices of the neurosurgical facilities performing spinal operations in Germany regarding patients who present for elective spinal surgery. Identical questionnaires were sent to 210 neurosurgical facilities and proffered five main questions: (1) the adherence of any policy of stopping aspirin pre-operatively, (2) the personal risk assessment for patients with spinal surgery under low-dose aspirin medication, (3) the preferred method of treatment for excessive bleeding in this context, (4) personal knowledge of hemorrhagic complications in this group of patients, and (5) the characteristics of the neurosurgical units concerned. There were 145 (69.1%) responses of which 142 (67.6%) were valid. Of the respondents, 114 (80.3%) had a (written) departmental policy for the discontinuation of pre-operative aspirin treatment, 28 (19.7%) were unaware of such a policy. The mean time suggested for discontinuation of aspirin pre-operatively was 6.9 days (range: 0-21 days), with seven respondents who perform the operations despite the ongoing aspirin medication. Ninety-four respondents (66.2%) considered that patients taking low-dose aspirin were at increased risk for excessive peri-operative hemorrhage or were indetermined (8.6%), and 73 (51.4%) reported having personal experience of such problems. Ninety-two respondents (65.5%) would use special medical therapy, preferably Desmopressin alone or in combination with other blood products or prohemostatic agents (46.1%), if hemorrhagic complications developed intra- or post-operatively. The average number of spinal operations per year in each service was 607.9 (range: 40-1,500). Despite the existence of distinct departmental policies concerning the discontinuation of low-dose aspirin pre-operatively in the majority of neurosurgical facilities performing spinal operations, there is a wide range of the moment of this interruption with an average of 7 days. Two-thirds of the respondents felt that aspirin was a risk factor for hemorrhagic complications associated with spinal procedures, and more than half of the interviewees reported having personal experience of such problems. Finally, various medicamentous methods of counteracting aspirin-induced platelet dysfunction and excessive bleeding in this context are elicited, discussed and evaluated.
Geothermal-retrofit study for the National Orange Show Facilities in San Bernardino, California
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-11-17
The cost and feasibility of retrofitting the National Orange Show Facilities to use geothermal heat instead of natural gas for heating are determined. Because of the limited usage of the smaller facilities the study was limited to the conversion of the six major buildings: Domed, Hobby, Citrus, Auditorium, Restaurant and Commercial. A major problem is that most of the buildings are used on a very limited basis. This drastically reduced the amount of savings that could be used to amortize the retrofit cost. Another problem is that the buildings are spread over a large area and so the below grademore » piping costs were high. Finally, all of the buildings except for the Auditorium have direct gas fired heaters that would require all new terminal heating systems. In order to limit the retrofit cost, the retrofit system was designed to handle less than the peak load. This seemed appropriate because the facility might not even be in operation when a peak load condition occurred. Also, the existing systems could be used to supplement the geothermal system if necessary. The calculated and design peak loads are summarized.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rosso, A.
Since the large North Eastern power system blackout on August 14, 2003, U.S. electric utilities have spent lot of effort on preventing power system cascading outages. Two of the main causes of the August 14, 2003 blackout were inadequate situational awareness and inadequate operator training In addition to the enhancements of the infrastructure of the interconnected power systems, more research and development of advanced power system applications are required for improving the wide-area security monitoring, operation and planning in order to prevent large- scale cascading outages of interconnected power systems. It is critically important for improving the wide-area situation awarenessmore » of the operators or operational engineers and regional reliability coordinators of large interconnected systems. With the installation of large number of phasor measurement units (PMU) and the related communication infrastructure, it will be possible to improve the operators’ situation awareness and to quickly identify the sequence of events during a large system disturbance for the post-event analysis using the real-time or historical synchrophasor data. The purpose of this project was to develop and demonstrate a novel synchrophasor-based comprehensive situational awareness system for control centers of power transmission systems. The developed system named WASA (Wide Area Situation Awareness) is intended to improve situational awareness at control centers of the power system operators and regional reliability coordinators. It consists of following main software modules: • Wide-area visualizations of real-time frequency, voltage, and phase angle measurements and their contour displays for security monitoring. • Online detection and location of a major event (location, time, size, and type, such as generator or line outage). • Near-real-time event replay (in seconds) after a major event occurs. • Early warning of potential wide-area stability problems. The system has been deployed and demonstrated at the Tennessee Valley Authority (TVA) and ISO New England system using real-time synchrophasor data from openPDC. Apart from the software product, the outcome of this project consists of a set of technical reports and papers describing the mathematical foundations and computational approaches of different tools and modules, implementation issues and considerations, lessons learned, and the results of lidation processes.« less
Numerical Solution of Time-Dependent Problems with a Fractional-Power Elliptic Operator
NASA Astrophysics Data System (ADS)
Vabishchevich, P. N.
2018-03-01
A time-dependent problem in a bounded domain for a fractional diffusion equation is considered. The first-order evolution equation involves a fractional-power second-order elliptic operator with Robin boundary conditions. A finite-element spatial approximation with an additive approximation of the operator of the problem is used. The time approximation is based on a vector scheme. The transition to a new time level is ensured by solving a sequence of standard elliptic boundary value problems. Numerical results obtained for a two-dimensional model problem are presented.
Monte Carlo Perturbation Theory Estimates of Sensitivities to System Dimensions
Burke, Timothy P.; Kiedrowski, Brian C.
2017-12-11
Here, Monte Carlo methods are developed using adjoint-based perturbation theory and the differential operator method to compute the sensitivities of the k-eigenvalue, linear functions of the flux (reaction rates), and bilinear functions of the forward and adjoint flux (kinetics parameters) to system dimensions for uniform expansions or contractions. The calculation of sensitivities to system dimensions requires computing scattering and fission sources at material interfaces using collisions occurring at the interface—which is a set of events with infinitesimal probability. Kernel density estimators are used to estimate the source at interfaces using collisions occurring near the interface. The methods for computing sensitivitiesmore » of linear and bilinear ratios are derived using the differential operator method and adjoint-based perturbation theory and are shown to be equivalent to methods previously developed using a collision history–based approach. The methods for determining sensitivities to system dimensions are tested on a series of fast, intermediate, and thermal critical benchmarks as well as a pressurized water reactor benchmark problem with iterated fission probability used for adjoint-weighting. The estimators are shown to agree within 5% and 3σ of reference solutions obtained using direct perturbations with central differences for the majority of test problems.« less
Yang, Chih-Cheng; Sheu, Shiann-Tsong
2013-01-01
This study investigates how to adjust the transmit power of femto base station (FBS) to mitigate interference problems between the FBSs and mobile users (MUs) in the 2-tier heterogeneous femtocell networks. A common baseline of deploying the FBS to increase the indoor access bandwidth requires that the FBS operation will not affect outdoor MUs operation with their quality-of-service (QoS) requirements. To tackle this technical problem, an FBS transmit power adjustment (FTPA) algorithm is proposed to adjust the FBS transmit power (FTP) to avoid unwanted cochannel interference (CCI) with the neighboring MUs in downlink transmission. FTPA reduces the FTP to serve its femto users (FUs) according to the QoS requirements of the nearest neighboring MUs to the FBS so that the MU QoS requirement is guaranteed. Simulation results demonstrate that FTPA can achieve a low MU outage probability as well as serve FUs without violating the MU QoS requirements. Simulation results also reveal that FTPA has better performance on voice and video services which are the major trend of future multimedia communication in the NGN. PMID:24391461
NASA Technical Reports Server (NTRS)
Mathews, Douglas; Bock, Larry A.; Bielak, Gerald W.; Dougherty, R. P.; Premo, John W.; Scharpf, Dan F.; Yu, Jia
2014-01-01
Major airports in the world's air transportation systems face a serious problem in providing greater capacity to meet the ever increasing demands of air travel. This problem could be relieved if airports are allowed to increase their operating time, now restricted by curfews and by relaxing present limits on takeoffs and landings. The key operational issue in extending the present curfews is noise. In response to these increasing restrictive noise regulations, NASA has launched a program to validate through engine testing, noise reduction concepts and technologies that have evolved from the Advanced Subsonic Technologies (AST) Noise Reduction Program. The goal of this AST program was to develop and validate technology that reduces engine noise and improves nacelle suppression effectiveness relative to 1992 technology. Contract NAS3-97144 titled "Engine Validation of Noise Reduction Concepts" (EVNRC) was awarded to P&W on August 12, 1997 to conduct full scale noise reduction tests in two Phases on a PW4098 engine. The following Section 1.2 provides a brief description of the overall program. The remainder of this report provides a detailed documentation of Phase I of the program.
Sarter, N B; Woods, D D
1997-12-01
Research and operational experience have shown that one of the major problems with pilot-automation interaction is a lack of mode awareness (i.e., the current and future status and behavior of the automation). As a result, pilots sometimes experience so-called automation surprises when the automation takes an unexpected action or fails to behave as anticipated. A lack of mode awareness and automation surprises can he viewed as symptoms of a mismatch between human and machine properties and capabilities. Changes in automation design can therefore he expected to affect the likelihood and nature of problems encountered by pilots. Previous studies have focused exclusively on early generation "glass cockpit" aircraft that were designed based on a similar automation philosophy. To find out whether similar difficulties with maintaining mode awareness are encountered on more advanced aircraft, a corpus of automation surprises was gathered from pilots of the Airbus A-320, an aircraft characterized by high levels of autonomy, authority, and complexity. To understand the underlying reasons for reported breakdowns in human-automation coordination, we also asked pilots about their monitoring strategies and their experiences with and attitude toward the unique design of flight controls on this aircraft.
NASA Technical Reports Server (NTRS)
Sarter, N. B.; Woods, D. D.
1997-01-01
Research and operational experience have shown that one of the major problems with pilot-automation interaction is a lack of mode awareness (i.e., the current and future status and behavior of the automation). As a result, pilots sometimes experience so-called automation surprises when the automation takes an unexpected action or fails to behave as anticipated. A lack of mode awareness and automation surprises can he viewed as symptoms of a mismatch between human and machine properties and capabilities. Changes in automation design can therefore he expected to affect the likelihood and nature of problems encountered by pilots. Previous studies have focused exclusively on early generation "glass cockpit" aircraft that were designed based on a similar automation philosophy. To find out whether similar difficulties with maintaining mode awareness are encountered on more advanced aircraft, a corpus of automation surprises was gathered from pilots of the Airbus A-320, an aircraft characterized by high levels of autonomy, authority, and complexity. To understand the underlying reasons for reported breakdowns in human-automation coordination, we also asked pilots about their monitoring strategies and their experiences with and attitude toward the unique design of flight controls on this aircraft.
GALAXY: A new hybrid MOEA for the optimal design of Water Distribution Systems
NASA Astrophysics Data System (ADS)
Wang, Q.; Savić, D. A.; Kapelan, Z.
2017-03-01
A new hybrid optimizer, called genetically adaptive leaping algorithm for approximation and diversity (GALAXY), is proposed for dealing with the discrete, combinatorial, multiobjective design of Water Distribution Systems (WDSs), which is NP-hard and computationally intensive. The merit of GALAXY is its ability to alleviate to a great extent the parameterization issue and the high computational overhead. It follows the generational framework of Multiobjective Evolutionary Algorithms (MOEAs) and includes six search operators and several important strategies. These operators are selected based on their leaping ability in the objective space from the global and local search perspectives. These strategies steer the optimization and balance the exploration and exploitation aspects simultaneously. A highlighted feature of GALAXY lies in the fact that it eliminates majority of parameters, thus being robust and easy-to-use. The comparative studies between GALAXY and three representative MOEAs on five benchmark WDS design problems confirm its competitiveness. GALAXY can identify better converged and distributed boundary solutions efficiently and consistently, indicating a much more balanced capability between the global and local search. Moreover, its advantages over other MOEAs become more substantial as the complexity of the design problem increases.
WEST-3 wind turbine simulator development. Volume 2: Verification
NASA Technical Reports Server (NTRS)
Sridhar, S.
1985-01-01
The details of a study to validate WEST-3, a new time wind turbine simulator developed by Paragib Pacific Inc., are presented in this report. For the validation, the MOD-0 wind turbine was simulated on WEST-3. The simulation results were compared with those obtained from previous MOD-0 simulations, and with test data measured during MOD-0 operations. The study was successful in achieving the major objective of proving that WEST-3 yields results which can be used to support a wind turbine development process. The blade bending moments, peak and cyclic, from the WEST-3 simulation correlated reasonably well with the available MOD-0 data. The simulation was also able to predict the resonance phenomena observed during MOD-0 operations. Also presented in the report is a description and solution of a serious numerical instability problem encountered during the study. The problem was caused by the coupling of the rotor and the power train models. The results of the study indicate that some parts of the existing WEST-3 simulation model may have to be refined for future work; specifically, the aerodynamics and procedure used to couple the rotor model with the tower and the power train models.
Eckmann, Christian; Olbrich, Guenter; Shekarriz, Hodjat; Bruch, Hans-Peter
2003-01-01
The reproducible advantages of minimal invasive surgery have led to a worldwide spread of these techniques. Nevertheless, the increasing use of technology causes problems in the operating room (OR). The workstation environment and workflow are handicapped by a great number of isolated solutions that demand a large amount of space. The Center of Excellence in Medical Technology (CEMET) was established in 2001 as an institution for a close cooperation between users, science, and manufacturers of medical devices in the State of Schleswig-Holstein, Germany. The future OR, as a major project, began with a detailed process analysis, which disclosed a large number of medical devices with different interfaces and poor standardisation as main problems. Smaller and more flexible devices are necessary, as well as functional modules located outside the OR. Only actuators should be positioned near the operation area. The future OR should include a flexible-room concept and less equipment than is in use currently. A uniform human-user interface is needed to control the OR environment. This article addresses the need for a clear workspace environment, intelligent-user interfaces, and flexible-room concept to improve the potentials in use of minimal invasive surgery.
Chen, Jenhui; Yang, Chih-Cheng; Sheu, Shiann-Tsong
2013-01-01
This study investigates how to adjust the transmit power of femto base station (FBS) to mitigate interference problems between the FBSs and mobile users (MUs) in the 2-tier heterogeneous femtocell networks. A common baseline of deploying the FBS to increase the indoor access bandwidth requires that the FBS operation will not affect outdoor MUs operation with their quality-of-service (QoS) requirements. To tackle this technical problem, an FBS transmit power adjustment (FTPA) algorithm is proposed to adjust the FBS transmit power (FTP) to avoid unwanted cochannel interference (CCI) with the neighboring MUs in downlink transmission. FTPA reduces the FTP to serve its femto users (FUs) according to the QoS requirements of the nearest neighboring MUs to the FBS so that the MU QoS requirement is guaranteed. Simulation results demonstrate that FTPA can achieve a low MU outage probability as well as serve FUs without violating the MU QoS requirements. Simulation results also reveal that FTPA has better performance on voice and video services which are the major trend of future multimedia communication in the NGN.
Review of computational fluid dynamics applications in biotechnology processes.
Sharma, C; Malhotra, D; Rathore, A S
2011-01-01
Computational fluid dynamics (CFD) is well established as a tool of choice for solving problems that involve one or more of the following phenomena: flow of fluids, heat transfer,mass transfer, and chemical reaction. Unit operations that are commonly utilized in biotechnology processes are often complex and as such would greatly benefit from application of CFD. The thirst for deeper process and product understanding that has arisen out of initiatives such as quality by design provides further impetus toward usefulness of CFD for problems that may otherwise require extensive experimentation. Not surprisingly, there has been increasing interest in applying CFD toward a variety of applications in biotechnology processing in the last decade. In this article, we will review applications in the major unit operations involved with processing of biotechnology products. These include fermentation,centrifugation, chromatography, ultrafiltration, microfiltration, and freeze drying. We feel that the future applications of CFD in biotechnology processing will focus on establishing CFD as a tool of choice for providing process understanding that can be then used to guide more efficient and effective experimentation. This article puts special emphasis on the work done in the last 10 years. © 2011 American Institute of Chemical Engineers
Preparation of Effective Operating Manuals to Support Waste Management Plant Operator Training
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, S. R.
2003-02-25
Effective plant operating manuals used in a formal training program can make the difference between a successful operation and a failure. Once the plant process design and control strategies have been fixed, equipment has been ordered, and the plant is constructed, the only major variable affecting success is the capability of plant operating personnel. It is essential that the myriad details concerning plant operation are documented in comprehensive operating manuals suitable for training the non-technical personnel that will operate the plant. These manuals must cover the fundamental principles of each unit operation including how each operates, what process variables aremore » important, and the impact of each variable on the overall process. In addition, operators must know the process control strategies, process interlocks, how to respond to alarms, each of the detailed procedures required to start up and optimize the plant, and every control loop-including when it is appropriate to take manual control. More than anything else, operating mistakes during the start-up phase can lead to substantial delays in achieving design processing rates as well as to problems with government authorities if environmental permit limits are exceeded. The only way to assure return on plant investment is to ensure plant operators have the knowledge to properly run the plant from the outset. A comprehensive set of operating manuals specifically targeted toward plant operators and supervisors written by experienced operating personnel is the only effective way to provide the necessary information for formal start-up training.« less
A Multi-wavelength Ozone Lidar for the EASOE Experiment
NASA Technical Reports Server (NTRS)
Godin, S.; Ancellet, G.; David, C.; Porteneuve, J.; Leroy, C.; Mitev, V.; Emery, Y.; Flesia, C.; Rizi, V.; Visconti, G.
1992-01-01
The study of the ozone layer during winter and springtime in high latitude regions is a major issue in atmospheric research. For a better understanding of these problems, an important experimental campaign called EASOE (European Arctic Stratospheric Ozone Experiment) was organized by the European Community during the winter 1991-1992. Its main objective was to establish a budget of the ozone destruction processes on the whole northern hemisphere. This implied the simultaneous operation of different types of instruments located in both high and mid-latitude regions in order to study the destruction processes as well as the evolution of the ozone layer during the period of the campaign. A description will be given here of a mobile ozone lidar instrument specially designed for operation during the EASOE campaign. This system, which performs ozone measurements in the 5 to 40 km altitude range was located in Sodankyla, Finland as part of the ELSA experiment which also includes operation of another multi-wavelength lidar designed for polar stratospheric cloud measurements.
A description of the verbal behavior of students during two reading instruction methods
Daly, Patricia M.
1987-01-01
The responses of students during two reading methods, the language experience approach and two Mastery Learning programs, were analyzed using verbal operants. A description of student responding was generated for these methods. The purpose of the study was to answer the questions: What are the major controlling variables determining student reading behavior during the language experience approach and two Mastery Learning programs, and how do these controlling variables change across story reading sessions and across stories in the first method? Student responses by verbal operant were compared for both reading methods. Findings indicated higher frequencies of textual operants occurred in responses during the Mastery Learning programs. A greater reliance on intraverbal control was evident in responses during the language experience approach. It is suggested that students who can generate strong intraverbal responses and who may have visual discrimination problems during early reading instruction may benefit from use of the language experience approach at this stage. ImagesFigure 2Figure 3 PMID:22477535
The MST radar technique: Requirements for operational weather forecasting
NASA Technical Reports Server (NTRS)
Larsen, M. F.
1983-01-01
There is a feeling that the accuracy of mesoscale forecasts for spatial scales of less than 1000 km and time scales of less than 12 hours can be improved significantly if resources are applied to the problem in an intensive effort over the next decade. Since the most dangerous and damaging types of weather occur at these scales, there are major advantages to be gained if such a program is successful. The interest in improving short term forecasting is evident. The technology at the present time is sufficiently developed, both in terms of new observing systems and the computing power to handle the observations, to warrant an intensive effort to improve stormscale forecasting. An assessment of the extent to which the so-called MST radar technique fulfills the requirements for an operational mesoscale observing network is reviewed and the extent to which improvements in various types of forecasting could be expected if such a network is put into operation are delineated.
Endsley, Mica R
2017-02-01
As autonomous and semiautonomous systems are developed for automotive, aviation, cyber, robotics and other applications, the ability of human operators to effectively oversee and interact with them when needed poses a significant challenge. An automation conundrum exists in which as more autonomy is added to a system, and its reliability and robustness increase, the lower the situation awareness of human operators and the less likely that they will be able to take over manual control when needed. The human-autonomy systems oversight model integrates several decades of relevant autonomy research on operator situation awareness, out-of-the-loop performance problems, monitoring, and trust, which are all major challenges underlying the automation conundrum. Key design interventions for improving human performance in interacting with autonomous systems are integrated in the model, including human-automation interface features and central automation interaction paradigms comprising levels of automation, adaptive automation, and granularity of control approaches. Recommendations for the design of human-autonomy interfaces are presented and directions for future research discussed.
Managing storm water at airports
DOE Office of Scientific and Technical Information (OSTI.GOV)
Halm, M.J.
1996-09-01
Airports are active facilities with numerous on-going operations at their sites. The following operations may adversely affect the water quality of nearby aquatic environments: De-icing runways; de-icing taxiways; de-icing and anti-icing aircraft; aircraft maintenance; and salt de-icer application. Until the amendments to the Clean Water Act of 1972, referred to as the Water Quality Act of 1987, were passed by Congress, the majority of storm water discharges in the US were unregulated. The Water Quality Act of 1987 was promulgated as an effort to manage the pollution resulting from storm water runoff. Many industrial facilities, especially airports, were faced withmore » complex problems in attempting to comply with these new federal regulations. National Pollution Discharge Elimination System (NPDES) permits for airports with more than 50,000 flight operations per year require periodic monitoring of receiving waters and storm sewer outfalls. The federal government has given states jurisdiction in issuing NPDES permits for storm water discharges. States may require composite or grab samples.« less
Multifuel industrial steam generation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mesko, J.E.
An inefficient, unreliable steam generation and distribution system at the Red River Army Depot (Texarkana, Tex.), a major industrial facility of the federal government, was replaced with a modern, multifuel-burning steam plant. In the new plant, steam is generated by three high-pressure field-erected boilers burning 100 percent coal, 100 percent refuse, or any combination of the two, while maintaining particulate emissions, SO{sub 2} concentration, and NO{sub x} and chlorine levels at or better than clean air standards. The plant, which has been in operation since 1986, is now part of the Army's Energy/Environment Showcase for demonstrating innovative technology to publicmore » and private operators. When the project began, the Red River depot faced several operational problems. Existing No. 2 oil- and gas- fired boilers in three separate boiler plants were inefficient, unreliable, and difficult to maintain. Extra boilers often had to be leased to provide for needed capacity. In addition, the facility had large quantities of waste to dispose of.« less
Accelerated life test of sputtering and anode deposit spalling in a small mercury ion thruster
NASA Technical Reports Server (NTRS)
Power, J. L.
1975-01-01
Tantalum and molybdenum sputtered from discharge chamber components during operation of a 5 centimeter diameter mercury ion thruster adhered much more strongly to coarsely grit blasted anode surfaces than to standard surfaces. Spalling of the sputtered coating did occur from a coarse screen anode surface but only in flakes less than a mesh unit long. The results were obtained in a 200 hour accelerated life test conducted at an elevated discharge potential of 64.6 volts. The test approximately reproduced the major sputter erosion and deposition effects that occur under normal operation but at approximately 75 times the normal rate. No discharge chamber component suffered sufficient erosion in the test to threaten its structural integrity or further serviceability. The test indicated that the use of tantalum-surfaced discharge chamber components in conjunction with a fine wire screen anode surface should cure the problems of sputter erosion and sputtered deposits spalling in long term operation of small mercury ion thrusters.
Epidemiology and Control of Neosporosis and Neospora caninum
Dubey, J. P.; Schares, G.; Ortega-Mora, L. M.
2007-01-01
Neospora caninum is a protozoan parasite of animals. Until 1988, it was misidentified as Toxoplasma gondii. Since its first recognition in dogs in 1984 and the description of the new genus and species Neospora caninum in 1988, neosporosis has emerged as a serious disease of cattle and dogs worldwide. Abortions and neonatal mortality are a major problem in livestock operations, and neosporosis is a major cause of abortion in cattle. Although antibodies to N. caninum have been reported, the parasite has not been detected in human tissues. Thus, the zoonotic potential is uncertain. This review is focused mainly on the epidemiology and control of neosporosis in cattle, but worldwide seroprevalences of N. caninum in animals and humans are tabulated. The role of wildlife in the life cycle of N. caninum and strategies for the control of neosporosis in cattle are discussed. PMID:17428888
Analysis of medical treatment at a field hospital following Hurricane Andrew, 1992.
Alson, R; Alexander, D; Leonard, R B; Stringer, L W
1993-11-01
To determine what medical care was required of a special operations response team by a community devastated by a major hurricane. Retrospective analysis of 1,544 patient encounter forms generated at a field hospital set up in Homestead, Florida, after Hurricane Andrew in August 1992 and staffed by the special operations response team from Forsyth County, North Carolina. All persons presenting for treatment. One thousand two hundred three adult patients and 336 pediatric patients were seen by the special operations response team. Only five of the injuries treated were due directly to the hurricane, whereas 285 of the treated injuries were sustained during clean-up activities. Most of the care provided was routine medical care denied the citizens due to the loss of their physicians' offices and clinics. Supplies of tetanus toxoid, antibiotics, and insulin were depleted in 24 hours. Resupplying these items and acquiring other medication to refill prescriptions constituted a pressing problem. The primary function of medical personnel responding to an area hit by a major hurricane will be to provide general medical care. Any trauma encountered will be primarily due to clean-up activities and not due to the hurricane itself. Responding medical personnel should plan on providing their own food and water for the first 72 hours and be well stocked with antibiotics, tetanus toxoid, and insulin.
Results of the Boeing/DOE DECC Phase 1 stirling engine project
DOE Office of Scientific and Technical Information (OSTI.GOV)
STONE,KENNETH W.; CLARK,TERRY; NELVING,HANS
2000-03-02
Phase I of Boeing Company/DOE Dish Engine Critical Component (DECC) Project started in April of 1998 and was completed in 1999. The Phase I objectives, schedule, and test results are presented in this paper. These data shows the power, energy, and mirror performance are comparable to that when the hardware was first manufactured 15 years ago. During the Phase I and initial Phase II test period the on-sun system accumulated over 3,800 hours of solar-powered operating time, accumulated over 4,500 hours of concentrator solar tracking time, and generated over 50,000 kWh of grid-compatible electrical energy. The data also shows thatmore » the system was available 95 {percent} of the time when the sun's insolation level was above approximately 300 w/m{sup 2}, and achieved a daily energy efficiency between 20{percent} and 26{percent}. A second concentrator was refurbished during Phase I and accumulated over 2,200 hours of solar track time. A second Stirling engine operated 24 hours a day in a test cell in Sweden and accumulated over 6,000 test hours. Discussion of daily operation shows no major problems encountered during the testing that would prevent commercialization of the technology. Further analysis of the test data shows that system servicing with hydrogen, coolant and lubricating oil should not be a major O and M cost.« less
Aircraft Safety and Operating Problems. [conference
NASA Technical Reports Server (NTRS)
1976-01-01
Results of NASA research in the field of aircraft safety and operating problems are discussed. Topics include: (1) terminal area operations, (2) flight dynamics and control; (3) ground operations; (4) atmospheric environment; (5) structures and materials; (6) powerplants; (7) noise; and (8) human factors engineering.
NASA Astrophysics Data System (ADS)
Li, Siwei; Li, Jun; Liu, Zhuochu; Wang, Min; Yue, Liang
2017-05-01
After the access of household distributed photovoltaic, conditions of high permeability generally occur, which cut off the connection between distributed power supply and major network rapidly and use energy storage device to realize electrical energy storage. The above operations cannot be adequate for the power grid health after distributed power supply access any more from the perspective of economy and rationality. This paper uses the integration between device and device, integration between device and system and integration between system and system of household microgrid and household energy efficiency management, to design household microgrid building program and operation strategy containing household energy efficiency management, to achieve efficient integration of household energy efficiency management and household microgrid, to effectively solve problems of high permeability of household distributed power supply and so on.
Teaching Reform of Civil Engineering Materials Course Based on Project-Driven Pedagogy
NASA Astrophysics Data System (ADS)
Yidong, Xu; Wei, Chen; WeiguoJian, You; Jiansheng, Shen
2018-05-01
In view of the scattered experimental projects in practical courses of civil engineering materials, the poor practical ability of students and the disconnection between practical teaching and theoretical teaching, this paper proposes a practical teaching procedure. Firstly, the single experiment should be offered which emphasizes on improving the students’ basic experimental operating ability. Secondly, the compressive experiment is offered and the overall quality of students can be examined in the form of project team. In order to investigate the effect of teaching reform, the comparative analysis of the students of three grades (2014, 2015 and 2016) majored in civil engineering was conducted. The result shows that the students’ ability of experimental operation is obviously improved by using the project driven method-based teaching reform. Besides, the students’ ability to analyse and solve problems has also been improved.
Xiong, Wei; Hupert, Nathaniel; Hollingsworth, Eric B; O'Brien, Megan E; Fast, Jessica; Rodriguez, William R
2008-01-01
Background Mathematical modeling has been applied to a range of policy-level decisions on resource allocation for HIV care and treatment. We describe the application of classic operations research (OR) techniques to address logistical and resource management challenges in HIV treatment scale-up activities in resource-limited countries. Methods We review and categorize several of the major logistical and operational problems encountered over the last decade in the global scale-up of HIV care and antiretroviral treatment for people with AIDS. While there are unique features of HIV care and treatment that pose significant challenges to effective modeling and service improvement, we identify several analogous OR-based solutions that have been developed in the service, industrial, and health sectors. Results HIV treatment scale-up includes many processes that are amenable to mathematical and simulation modeling, including forecasting future demand for services; locating and sizing facilities for maximal efficiency; and determining optimal staffing levels at clinical centers. Optimization of clinical and logistical processes through modeling may improve outcomes, but successful OR-based interventions will require contextualization of response strategies, including appreciation of both existing health care systems and limitations in local health workforces. Conclusion The modeling techniques developed in the engineering field of operations research have wide potential application to the variety of logistical problems encountered in HIV treatment scale-up in resource-limited settings. Increasing the number of cross-disciplinary collaborations between engineering and public health will help speed the appropriate development and application of these tools. PMID:18680594
A fast pulse design for parallel excitation with gridding conjugate gradient.
Feng, Shuo; Ji, Jim
2013-01-01
Parallel excitation (pTx) is recognized as a crucial technique in high field MRI to address the transmit field inhomogeneity problem. However, it can be time consuming to design pTx pulses which is not desirable. In this work, we propose a pulse design with gridding conjugate gradient (CG) based on the small-tip-angle approximation. The two major time consuming matrix-vector multiplications are substituted by two operators which involves with FFT and gridding only. Simulation results have shown that the proposed method is 3 times faster than conventional method and the memory cost is reduced by 1000 times.
Usefulness of the infrared heterodyne radiometer in remote sensing of atmospheric pollutants.
NASA Technical Reports Server (NTRS)
Menzies, R. T.; Shumate, M. S.
1971-01-01
The application of narrow-band optical receivers to the problem of sensing atmospheric pollution is discussed. The emission/absorption lines of many major atmospheric pollutant molecules overlap the operating frequency bands of CO2 laser and CO laser heterodyne receivers. Several remote pollution sensing systems which are based upon utilization of these spectral overlaps are described, and an analysis of their potential is presented. The possibility of using other lasers (e.g.: the PbSnTe tunable diode laser) as local oscillators is also considered. Results of laboratory experiments with a CO2 laser heterodyne radiometer are presented.
Non-invasive assessment of thromboembolism in rotary blood pumps: case study
NASA Astrophysics Data System (ADS)
Gawlikowski, Maciej; Kustosz, Roman; Głowacki, Maciej; Pydziński, Paweł; Kubacki, Krzysztof; Zakliczyński, Michał; Copik, Izabela; Pacholewicz, Jerzy
2017-08-01
Thromboembolic complications are one of the major problems in mechanical heart support of patients suffering from critical heart failure. The goal of the study was to present and discuss methodology of non-invasive assessment of embolization in rotary blood pumps. The study was carried out based on power consumption trend analysis as well as spectral analysis of acoustic signal produced by the pump during its operation. It has been demonstrated that the trend of power rising and presence of 3rd harmonic in acoustic spectrum corresponds to the clinical symptoms of pump embolization.
APGEN Scheduling: 15 Years of Experience in Planning Automation
NASA Technical Reports Server (NTRS)
Maldague, Pierre F.; Wissler, Steve; Lenda, Matthew; Finnerty, Daniel
2014-01-01
In this paper, we discuss the scheduling capability of APGEN (Activity Plan Generator), a multi-mission planning application that is part of the NASA AMMOS (Advanced Multi- Mission Operations System), and how APGEN scheduling evolved over its applications to specific Space Missions. Our analysis identifies two major reasons for the successful application of APGEN scheduling to real problems: an expressive DSL (Domain-Specific Language) for formulating scheduling algorithms, and a well-defined process for enlisting the help of auxiliary modeling tools in providing high-fidelity, system-level simulations of the combined spacecraft and ground support system.
[Legal aspects of the use of footbaths for cattle and sheep].
Kleiminger, E
2012-04-24
Claw diseases pose a major problem for dairy and sheep farms. As well as systemic treatments of these illnesses by means of drug injection, veterinarians discuss the application of footbaths for the local treatment of dermatitis digitalis or foot rot. On farms footbaths are used with different substances and for various purposes. The author presents the requirements for veterinary medicinal products (marketing authorization and manufacturing authorization) and demonstrates the operation of the "cascade in case of a treatment crisis". In addition, the distinction between veterinary hygiene biocidal products and veterinary medicinal products and substances to care for claws is explained.
Development of an experiment for visible radiation measurements from a satellite
NASA Technical Reports Server (NTRS)
Sekera, Z.; Bradbury, R. E.
1973-01-01
The inversion problem, I.E., determining the atmospheric turbidity from polarimetry of radiation emerging from the earth's atmosphere, is presented. A major theoretical advance was made by finding a successful approximation for the forward peak scattering of aerosols together with a simplified characterization of particle size distributions. An engineering model of a multibarreled photopolarimeter suitable for operation from a satellite was evaluated in laboratory and high altitude jet aircraft tests. Comparison of the data from flights over the Mexican desert with theoretical curves for a Rayleigh atmosphere with negligible turbidity is in agreement.
Scaling fixed-field alternating gradient accelerators with a small orbit excursion.
Machida, Shinji
2009-10-16
A novel scaling type of fixed-field alternating gradient (FFAG) accelerator is proposed that solves the major problems of conventional scaling and nonscaling types. This scaling FFAG accelerator can achieve a much smaller orbit excursion by taking a larger field index k. A triplet focusing structure makes it possible to set the operating point in the second stability region of Hill's equation with a reasonable sensitivity to various errors. The orbit excursion is about 5 times smaller than in a conventional scaling FFAG accelerator and the beam size growth due to typical errors is at most 10%.
Foil system fatigue load environments for commercial hydrofoil operation
NASA Technical Reports Server (NTRS)
Graves, D. L.
1979-01-01
The hydrofoil fatigue loads environment in the open sea is examined. The random nature of wave orbital velocities, periods and heights plus boat heading, speed and control system design are considered in the assessment of structural fatigue requirements. Major nonlinear load events such as hull slamming and foil unwetting are included in the fatigue environment. Full scale rough water load tests, field experience plus analytical loads work on the model 929 Jetfoil commercial hydrofoil are discussed. The problem of developing an overall sea environment for design is defined. State of the art analytical approaches are examined.
Review of factors affecting aircraft wet runway performance
NASA Technical Reports Server (NTRS)
Yager, T. J.
1983-01-01
Problems associated with aircraft operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from investigations conducted at the Langley Aircraft Landing Loads and Traction Facility and from tests with instrumented ground vehicles and aircraft are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.
The quiet revolution of numerical weather prediction.
Bauer, Peter; Thorpe, Alan; Brunet, Gilbert
2015-09-03
Advances in numerical weather prediction represent a quiet revolution because they have resulted from a steady accumulation of scientific knowledge and technological advances over many years that, with only a few exceptions, have not been associated with the aura of fundamental physics breakthroughs. Nonetheless, the impact of numerical weather prediction is among the greatest of any area of physical science. As a computational problem, global weather prediction is comparable to the simulation of the human brain and of the evolution of the early Universe, and it is performed every day at major operational centres across the world.
NASA Technical Reports Server (NTRS)
Kessler, D. J. (Compiler); Su, S. Y. (Compiler)
1985-01-01
Earth orbital debris issues and recommended future activities are discussed. The workshop addressed the areas of environment definition, hazards to spacecraft, and space object management. It concluded that orbital debris is a potential problem for future space operations. However, before recommending any major efforts to control the environment, more data are required. The most significant required data are on the population of debris smaller than 4 cm in diameter. New damage criteria are also required. When these data are obtained, they can be combined with hypervelocity data to evaluate the hazards to future spacecraft. After these hazards are understood, then techniques to control the environment can be evaluated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lazarus, E; Peng, Yueng Kay Martin
Oak Ridge National Laboratory (ORNL) proposes to build the Spherical Torus Experiment (STX), a very low aspect ratio toroidal confinement device. This proposal concentrates on tokamak operation of the experiment; however, it can in principle be operated as a pinch or reversed-field pinch as well. As a tokamak, the spherical torus confines a plasma that is characterized by high toroidal beta, low poloidal beta, large natural elongation, high plasma current for a given edge q, and strong paramagnetism. These features combine to offer the possibility of a compact, low-field fusion device. The figure below shows that when compared to amore » conventional tokamak the spherical torus represents a major change in geometry. The primary goals of the experiment will be to demonstrate a capability for high beta (20%) in the first stability regime, to extend our knowledge of tokamak confinement scaling, and to test oscillating-field current drive. The experiment will operate in the high-beta, collisionless regime, which is achieved in STX at low temperatures because of the geometry. At a minimum, operation of STX will help to resolve fundamental questions regarding the scaling of beta and confinement in tokamaks. Complete success in this program would have a significant impact on toroidal fusion research in that it would demonstrate solutions to the problems of beta and steady-state operation in the tokamak. The proposed device has a major radius of 0.45 m, a toroidai field of 0.5 T, a plasma current of 900 kA, and heating by neutral beam injection. We estimate 30 months for design, construction, and assembly. The budget estimate, including contingency and escalation, is $6.8 million.« less
Optimization problems in natural gas transportation systems. A state-of-the-art review
Ríos-Mercado, Roger Z.; Borraz-Sánchez, Conrado
2015-03-24
Our paper provides a review on the most relevant research works conducted to solve natural gas transportation problems via pipeline systems. The literature reveals three major groups of gas pipeline systems, namely gathering, transmission, and distribution systems. In this work, we aim at presenting a detailed discussion of the efforts made in optimizing natural gas transmission lines.There is certainly a vast amount of research done over the past few years on many decision-making problems in the natural gas industry and, specifically, in pipeline network optimization. In this work, we present a state-of-the-art survey focusing on specific categories that include short-termmore » basis storage (line-packing problems), gas quality satisfaction (pooling problems), and compressor station modeling (fuel cost minimization problems). We also discuss both steady-state and transient optimization models highlighting the modeling aspects and the most relevant solution approaches known to date. Although the literature on natural gas transmission system problems is quite extensive, this is, to the best of our knowledge, the first comprehensive review or survey covering this specific research area on natural gas transmission from an operations research perspective. Furthermore, this paper includes a discussion of the most important and promising research areas in this field. Hence, our paper can serve as a useful tool to gain insight into the evolution of the many real-life applications and most recent advances in solution methodologies arising from this exciting and challenging research area of decision-making problems.« less
Optimization problems in natural gas transportation systems. A state-of-the-art review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ríos-Mercado, Roger Z.; Borraz-Sánchez, Conrado
Our paper provides a review on the most relevant research works conducted to solve natural gas transportation problems via pipeline systems. The literature reveals three major groups of gas pipeline systems, namely gathering, transmission, and distribution systems. In this work, we aim at presenting a detailed discussion of the efforts made in optimizing natural gas transmission lines.There is certainly a vast amount of research done over the past few years on many decision-making problems in the natural gas industry and, specifically, in pipeline network optimization. In this work, we present a state-of-the-art survey focusing on specific categories that include short-termmore » basis storage (line-packing problems), gas quality satisfaction (pooling problems), and compressor station modeling (fuel cost minimization problems). We also discuss both steady-state and transient optimization models highlighting the modeling aspects and the most relevant solution approaches known to date. Although the literature on natural gas transmission system problems is quite extensive, this is, to the best of our knowledge, the first comprehensive review or survey covering this specific research area on natural gas transmission from an operations research perspective. Furthermore, this paper includes a discussion of the most important and promising research areas in this field. Hence, our paper can serve as a useful tool to gain insight into the evolution of the many real-life applications and most recent advances in solution methodologies arising from this exciting and challenging research area of decision-making problems.« less
Training potential in minimally invasive surgery in a tertiary care, paediatric urology centre.
Schroeder, R P J; Chrzan, R J; Klijn, A J; Kuijper, C F; Dik, P; de Jong, T P V M
2015-10-01
Minimally invasive surgery (MIS) is being utilized more frequently as a surgical technique in general surgery and in paediatric urology. It is associated with a steep learning curve. Currently, the centre does not offer a MIS training programme. It is hypothesized that the number of MIS procedures performed in the low-volume specialty of paediatric urology will offer insufficient training potential for surgeons. To assess the MIS training potential of a highly specialized, tertiary care, paediatric urology training centre that has been accredited by the Joint Committee of Paediatric Urology (JCPU). The clinical activity of the department was retrospectively reviewed by extracting the annual number of admissions, outpatient consultations and operative procedures. The operations were divided into open procedures and MIS. Major ablative procedures (nephrectomy) and reconstructive procedures (pyeloplasty) were analysed with reference to the patients' ages. The centre policy is not to perform major MIS in children who are under 2 years old or who weigh less than 12 kg. Every year, this institution provides approximately 4300 out-patient consultations, 600 admissions, and 1300 procedures under general anaesthesia for children with urological problems. In 2012, 35 patients underwent major intricate MIS: 16 pyeloplasties, eight nephrectomies and 11 operations for incontinence (seven Burch, and four bladder neck procedures). In children ≥2 years of age, 16/21 of the pyeloplasties and 8/12 of the nephrectomies were performed laparoscopically. The remaining MIS procedures included 25 orchidopexies and one intravesical ureteral reimplantation. There is no consensus on how to assess laparoscopic training. It would be valuable to reach a consensus on a standardized laparoscopic training programme in paediatric urology. Often training potential is based on operation numbers only. In paediatric urology no minimum requirement has been specified. The number of procedures quoted for proficiency in MIS remains controversial. The MIS numbers for this centre correspond to, or exceed, numbers mentioned in other literature. To provide high-quality MIS training, exposure to laparoscopic procedures should be expanded. This may be achieved by centralizing patients into a common centre, collaborating with other specialities, modular training and training outside the operating theatre. Even in a high-volume, paediatric urology educational centre, the number of major MIS procedures performed remains relatively low, leading to limited training potential. Copyright © 2015. Published by Elsevier Ltd.
Real-Time Operation of the International Space Station
NASA Astrophysics Data System (ADS)
Suffredini, M. T.
2002-01-01
The International Space Station is on orbit and real-time operations are well underway. Along with the assembly challenges of building and operating the International Space Station , scientific activities are also underway. Flight control teams in three countries are working together as a team to plan, coordinate and command the systems on the International Space Station.Preparations are being made to add the additional International Partner elements including their operations teams and facilities. By October 2002, six Expedition crews will have lived on the International Space Station. Management of real-time operations has been key to these achievements. This includes the activities of ground teams in control centers around the world as well as the crew on orbit. Real-time planning is constantly challenged with balancing the requirements and setting the priorities for the assembly, maintenance, science and crew health functions on the International Space Station. It requires integrating the Shuttle, Soyuz and Progress requirements with the Station. It is also necessary to be able to respond in case of on-orbit anomalies and to set plans and commands in place to ensure the continues safe operation of the Station. Bringing together the International Partner operations teams has been challenging and intensely rewarding. Utilization of the assets of each partner has resulted in efficient solutions to problems. This paper will describe the management of the major real-time operations processes, significant achievements, and future challenges.
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.
An Assessment of Operational Energy Capability Improvement Fund (OECIF) Programs 17-S-2544
2017-09-19
persistently attack key operational energy problems . OECIF themes are summarized in Table 1, and Appendix A includes more detail on the programs within... problems FY 2014 Analytical methods and tools FY 2015 Improving fuel economy for the current tactical ground fleet FY 2016 Increasing the operational...involve a variety of organizations to solve operational energy problems . In FY 2015, the OECIF program received a one-time $14.1M Congressional plus-up
NASA Technical Reports Server (NTRS)
Kennedy, Robert S.; Jones, Marshall B.; Baltzley, Dennis R.
1988-01-01
A major application of isoperformance is as a trade-off methodology of the three major drivers of system design; equipment, training variables, and user characteristics. The flexibility of isoperformance allows each of these three components to be nearly any rational variation. For example, aptitude may be military Armed Forces Qualification Testing (AFQT) categories, cutoff scores within a selection procedure, or simply dichotomizing high and low scorers (pass/fail). Equipment may be new versus old, 'smart' versus dumb, high versus low resolution, etc. Training may be short versus long or varieties of media types (lecture versus CAI/CBI versus self-paced workbooks). In its final computerized form isoperformance lets the user set an operational level of performance (e.g., a jet pilot in a simulated emergency must take prescribed corrective action and clear the plane in several seconds, pilot astronauts will check out all shuttle flight systems within 30 minutes, or Mission Specialists must handle sucdessfully a required number of job elements). At this point the computer program guides the user through any requested trade-offs of the three components while maintaining the specified operational level of performance through isoperformance curves. A demonstration of the computer program is currently available.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chergui, B.
1986-01-01
The major part of this study deals specifically with problems encountered in liquefied-gas production in Algeria. However, its developed methodology could be applied to other industrial units of similar importance (petrochemical, pipeline, etc.). Capital costs as well as manpower, operations, and maintenance costs are very high in such production, especially in Algeria, a foreign-technology dependent country. Moreover, the technical complexity of an LNG plan constitutes a further incentive for the formulation of mathematical models as tools toward attaining management efficiency. These models can form the basis for Decision Support Systems for use as well in improving the operations of anymore » major national industrial plant. The remainder of the dissertation consists of a conception and a study for an optimal firewater safety system for the Holy Area of Mina, in Saudi Arabia, where fire outbreaks cause significant losses in lives and property damages during the yearly pilgrimage. Part of the contribution of this study lies in the guidelines established for a Decision Support System, which will improve the user's effectiveness as a decision maker.« less
Development of coatings to control electroosmosis in zero gravity electrophoresis
NASA Technical Reports Server (NTRS)
Krupnick, A. C.
1974-01-01
A major problem confronting the operation of free fluid electrophoresis in zero gravity is the control of electrokinetic phenomena and, in particular, electroosmosis. Due to the severity of counter flow, as a result of electroosmosis, the electrical potential developed at the surface of shear must be maintained at near, or as close to, zero millivolts as possible. Based upon this investigation, it has been found that the amount of bound water or the degree of hydroxylation plays a major role in the control of this phenomena. Of necessity, factors, such as adhesion, biocompatibility, protein adsorption, and insolubility were considered in this investigation because of the long buffer-coating exposure times required by present space operations. Based upon tests employing microcapillary electrophoresis, it has been found that gamma amino propyl trihydroxysilane produced a coating which provides the lowest potential (minus 3.86 mv) at the surface of shear between the stationary and mobile layers. This coating has been soaked in both borate and saline buffers, up to three months, in a pH range of 6.5 to 10 without deleterious effects or a change in its ability to control electrokinetic effects.
Assessment of vehicle safety problems for special driving populations
DOT National Transportation Integrated Search
1979-02-16
The report describes vehicle safety problems reported in interviews with 460 physically limited drivers and 41 physically limited non-drivers. The problems reported involved operation of primary and secondary controls, operating other vehicle mechani...
Chen, Joy C; Shaw, Jeremy D; Ma, Yifei; Rhoads, Kim F
2016-02-01
Hospital readmission after major surgery is a costly problem that has been associated with patient characteristics. Because hospitals are incentivized to join accountable care organizations, interventions on a hospital or health care system level may help reduce readmissions. Our objective was to identify hospital- and systems-level characteristics associated with readmissions after major operative procedures. Retrospective analysis of California discharge abstracts with record linkage numbers for adult patients undergoing coronary artery bypass graft (CABG), colectomy or total hip/knee arthroplasty (TJA) in California acute, nonfederal hospitals in 2011. The record linkage number showed where patients were readmitted. Hierarchic logistic regression estimated the odds of readmission by hospital characteristics. There were 91,205 records analyzed: CABG (6.4%), colectomy (12.0%), and TJA (82.3%). There were 120 hospitals that performed CABG surgery; 296 performed colectomy; and 298 performed TJA. Readmission rates after CABG was 9.7%, colectomy 7.7%, and TJA 3.9%. After adjustment for patient factors, rural location was predictive of readmission after colectomy (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.40-3.08). Low-volume (OR 1.54, 95% CI 1.13-2.10) and minority-serving hospitals (OR 1.18, 95% CI 1.05-1.33) were associated with greater odds of readmission after TJA. Select hospital characteristics are associated with readmissions after major operative procedures. Because financial penalties may worsen performance in vulnerable or low-resource settings, policies aimed at reducing readmissions should be attentive to the potential unintended consequences. Copyright © 2016 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
McAllister, Cheryl J.; Beaver, Cheryl
2012-01-01
The purpose of this research was to determine if recognizable error types exist in the work of preservice teachers required to create story problems for specific fraction operations. Students were given a particular single-operation fraction expression and asked to do the calculation and then create a story problem that would require the use of…
A case study of hospital operations management.
Cheng, T C
1987-12-01
This paper discusses a study to investigate various operations management problems in a newly opened, modern regional hospital in Hong Kong. The findings of the study reveal that there exist in the hospital a number of current and potential problem areas. Recommendations for solving these problems are suggested with a view to improving the overall operational efficiency and effectiveness of the hospital.
Additive schemes for certain operator-differential equations
NASA Astrophysics Data System (ADS)
Vabishchevich, P. N.
2010-12-01
Unconditionally stable finite difference schemes for the time approximation of first-order operator-differential systems with self-adjoint operators are constructed. Such systems arise in many applied problems, for example, in connection with nonstationary problems for the system of Stokes (Navier-Stokes) equations. Stability conditions in the corresponding Hilbert spaces for two-level weighted operator-difference schemes are obtained. Additive (splitting) schemes are proposed that involve the solution of simple problems at each time step. The results are used to construct splitting schemes with respect to spatial variables for nonstationary Navier-Stokes equations for incompressible fluid. The capabilities of additive schemes are illustrated using a two-dimensional model problem as an example.
Investigation of Desiccants and CO2 Sorbents for Advanced Exploration Systems 2015-2016
NASA Technical Reports Server (NTRS)
Knox, James C.; Cmarik, Gregory E.; Watson, David
2016-01-01
Design of advanced carbon dioxide removal systems begins with the study of sorbents. Specifically, new CO2 sorbents and desiccants need to be studied to enable greater productivity from existing and future spaceflight systems. This presentation will discuss the studies used as input for selecting future CO2 sorbent materials. Also, the adjoining issues of understanding the effects of water co-adsorption and material selection for desiccant beds will be discussed. Current sorbents for CO2 removal are based on 5A zeolites, but a transition to sorbents derived from 13X will be necessary as CO2 levels in cabin air become leaner. Unfortunately, these 13X zeolites are more susceptible to long-term performance loss due to water co-adsorption than 5A due at achievable regeneration temperatures. A study on how impactful the presence of trace water will be to the cyclic operation of small-scale beds will be discussed. Also, methods to recover the performance of beds in a space environment after a major moisture adsorption event will be discussed. The information obtained from the water co-adsorption studies will play a major part in selecting a CO2 sorbent for advanced removal systems. Pellet structural properties play another major role in the selection process. One factor for long-term, hands-off operation of a system is pellet integrity. Maintaining integrity means preventing pellet fracture and the generation of fines due to various thermal and mechanical means which would eventually clog filters or damage downstream systems. Either of these problems require significant shutdowns and maintenance operations and must be avoided. Therefore, study of high-integrity pellets and design of new pellets will be discussed.
Locating underwater objects. [technology transfer
NASA Technical Reports Server (NTRS)
Grice, C. F.
1974-01-01
Underwater search operations are considered to be engineering and operational problems. A process for proper definition of the problem and selection of instrumentation and operational procedures is described. An outline of underwater search instrumentation and techniques is given.
Hoffmann, Jürgen; Wallwiener, Diethelm
2009-04-08
One of the basic prerequisites for generating evidence-based data is the availability of classification systems. Attempts to date to classify breast cancer operations have focussed on specific problems, e.g. the avoidance of secondary corrective surgery for surgical defects, rather than taking a generic approach. Starting from an existing, simpler empirical scheme based on the complexity of breast surgical procedures, which was used in-house primarily in operative report-writing, a novel classification of ablative and breast-conserving procedures initially needed to be developed and elaborated systematically. To obtain proof of principle, a prospectively planned analysis of patient records for all major breast cancer-related operations performed at our breast centre in 2005 and 2006 was conducted using the new classification. Data were analysed using basic descriptive statistics such as frequency tables. A novel two-type, six-tier classification system comprising 12 main categories, 13 subcategories and 39 sub-subcategories of oncological, oncoplastic and reconstructive breast cancer-related surgery was successfully developed. Our system permitted unequivocal classification, without exception, of all 1225 procedures performed in 1166 breast cancer patients in 2005 and 2006. Breast cancer-related surgical procedures can be generically classified according to their surgical complexity. Analysis of all major procedures performed at our breast centre during the study period provides proof of principle for this novel classification system. We envisage various applications for this classification, including uses in randomised clinical trials, guideline development, specialist surgical training, continuing professional development as well as quality of care and public health research.
The World Health Organization and public health research and practice in tuberculosis in India.
Banerji, Debabar
2012-01-01
Two major research studies carried out in India fundamentally affected tuberculosis treatment practices worldwide. One study demonstrated that home treatment of the disease is as efficacious as sanatorium treatment. The other showed that BCG vaccination is of little protective value from a public health viewpoint. India had brought together an interdisciplinary team at the National Tuberculosis Institute (NTI) with a mandate to formulate a nationally applicable, socially acceptable, and epidemiologically sound National Tuberculosis Programme (NTP). Work at the NTI laid the foundation for developing an operational research approach to dealing with tuberculosis as a public health problem. The starting point for this was not operational research as enunciated by experts in this field; rather, the NTI achieved operational research by starting from the people. This approach was enthusiastically welcomed by the World Health Organization's Expert Committee on Tuberculosis of 1964. The NTP was designed to "sink or sail with the general health services of the country." The program was dealt a major blow when, starting in 1967, a virtual hysteria was worked up to mobilize most of the health services for imposing birth control on the people. Another blow to the general health services occurred when the WHO joined the rich countries in instituting a number of vertical programs called "Global Initiatives". An ill-conceived, ill-designed, and ill-managed Global Programme for Tuberculosis was one outcome. The WHO has shown rank public health incompetence in taking a very casual approach to operational research and has been downright quixotic in its thinking on controlling tuberculosis worldwide.
NASA Astrophysics Data System (ADS)
Ibrahim, Bashirah; Ding, Lin; Heckler, Andrew F.; White, Daniel R.; Badeau, Ryan
2017-12-01
We examine students' mathematical performance on quantitative "synthesis problems" with varying mathematical complexity. Synthesis problems are tasks comprising multiple concepts typically taught in different chapters. Mathematical performance refers to the formulation, combination, and simplification of equations. Generally speaking, formulation and combination of equations require conceptual reasoning; simplification of equations requires manipulation of equations as computational tools. Mathematical complexity is operationally defined by the number and the type of equations to be manipulated concurrently due to the number of unknowns in each equation. We use two types of synthesis problems, namely, sequential and simultaneous tasks. Sequential synthesis tasks require a chronological application of pertinent concepts, and simultaneous synthesis tasks require a concurrent application of the pertinent concepts. A total of 179 physics major students from a second year mechanics course participated in the study. Data were collected from written tasks and individual interviews. Results show that mathematical complexity negatively influences the students' mathematical performance on both types of synthesis problems. However, for the sequential synthesis tasks, it interferes only with the students' simplification of equations. For the simultaneous synthesis tasks, mathematical complexity additionally impedes the students' formulation and combination of equations. Several reasons may explain this difference, including the students' different approaches to the two types of synthesis problems, cognitive load, and the variation of mathematical complexity within each synthesis type.
a Stochastic Approach to Multiobjective Optimization of Large-Scale Water Reservoir Networks
NASA Astrophysics Data System (ADS)
Bottacin-Busolin, A.; Worman, A. L.
2013-12-01
A main challenge for the planning and management of water resources is the development of multiobjective strategies for operation of large-scale water reservoir networks. The optimal sequence of water releases from multiple reservoirs depends on the stochastic variability of correlated hydrologic inflows and on various processes that affect water demand and energy prices. Although several methods have been suggested, large-scale optimization problems arising in water resources management are still plagued by the high dimensional state space and by the stochastic nature of the hydrologic inflows. In this work, the optimization of reservoir operation is approached using approximate dynamic programming (ADP) with policy iteration and function approximators. The method is based on an off-line learning process in which operating policies are evaluated for a number of stochastic inflow scenarios, and the resulting value functions are used to design new, improved policies until convergence is attained. A case study is presented of a multi-reservoir system in the Dalälven River, Sweden, which includes 13 interconnected reservoirs and 36 power stations. Depending on the late spring and summer peak discharges, the lowlands adjacent to Dalälven can often be flooded during the summer period, and the presence of stagnating floodwater during the hottest months of the year is the cause of a large proliferation of mosquitos, which is a major problem for the people living in the surroundings. Chemical pesticides are currently being used as a preventive countermeasure, which do not provide an effective solution to the problem and have adverse environmental impacts. In this study, ADP was used to analyze the feasibility of alternative operating policies for reducing the flood risk at a reasonable economic cost for the hydropower companies. To this end, mid-term operating policies were derived by combining flood risk reduction with hydropower production objectives. The performance of the resulting policies was evaluated by simulating the online operating process for historical inflow scenarios and synthetic inflow forecasts. The simulations are based on a combined mid- and short-term planning model in which the value function derived in the mid-term planning phase provides the value of the policy at the end of the short-term operating horizon. While a purely deterministic linear analysis provided rather optimistic results, the stochastic model allowed for a more accurate evaluation of trade-offs and limitations of alternative operating strategies for the Dalälven reservoir network.
Common display performance requirements for military and commercial aircraft product lines
NASA Astrophysics Data System (ADS)
Hoener, Steven J.; Behrens, Arthur J.; Flint, John R.; Jacobsen, Alan R.
2001-09-01
Obtaining high quality Active Matrix Liquid Crystal (AMLCD) glass to meet the needs of the commercial and military aerospace business is a major challenge, at best. With the demise of all domestic sources of AMLCD substrate glass, the industry is now focused on overseas sources, which are primarily producing glass for consumer electronics. Previous experience with ruggedizing commercial glass leads to the expectation that the aerospace industry can leverage off the commercial market. The problem remains, while the commercial industry is continually changing and improving its products, the commercial and military aerospace industries require stable and affordable supplies of AMLCD glass for upwards of 20 years to support production and maintenance operations. The Boeing Engineering and Supplier Management Process Councils have chartered a group of displays experts from multiple aircraft product divisions within the Boeing Company, the Displays Process Action Team (DPAT), to address this situation from an overall corporate perspective. The DPAT has formulated a set of Common Displays Performance Requirements for use across the corporate line of commercial and military aircraft products. Though focused on the AMLCD problem, the proposed common requirements are largely independent of display technology. This paper describes the strategy being pursued within the Boeing Company to address the AMLCD supply problem and details the proposed implementation process, centered on common requirements for both commercial and military aircraft displays. Highlighted in this paper are proposed common, or standard, display sizes and the other major requirements established by the DPAT, along with the rationale for these requirements.
A New Approach to Data Publication in Ocean Sciences
NASA Astrophysics Data System (ADS)
Lowry, Roy; Urban, Ed; Pissierssens, Peter
2009-12-01
Data are collected from ocean sciences activities that range from a single investigator working in a laboratory to large teams of scientists cooperating on big, multinational, global ocean research projects. What these activities have in common is that all result in data, some of which are used as the basis for publications in peer-reviewed journals. However, two major problems regarding data remain. First, many data valuable for understanding ocean physics, chemistry, geology, biology, and how the oceans operate in the Earth system are never archived or made accessible to other scientists. Data underlying traditional journal articles are often difficult to obtain. Second, when scientists do contribute data to databases, their data become freely available, with little acknowledgment and no contribution to their career advancement. To address these problems, stronger ties must be made between data repositories and academic journals, and a “digital backbone” needs to be created for data related to journal publications.
Optimization techniques applied to passive measures for in-orbit spacecraft survivability
NASA Technical Reports Server (NTRS)
Mog, Robert A.; Price, D. Marvin
1991-01-01
Spacecraft designers have always been concerned about the effects of meteoroid impacts on mission safety. The engineering solution to this problem has generally been to erect a bumper or shield placed outboard from the spacecraft wall to disrupt/deflect the incoming projectiles. Spacecraft designers have a number of tools at their disposal to aid in the design process. These include hypervelocity impact testing, analytic impact predictors, and hydrodynamic codes. Analytic impact predictors generally provide the best quick-look estimate of design tradeoffs. The most complete way to determine the characteristics of an analytic impact predictor is through optimization of the protective structures design problem formulated with the predictor of interest. Space Station Freedom protective structures design insight is provided through the coupling of design/material requirements, hypervelocity impact phenomenology, meteoroid and space debris environment sensitivities, optimization techniques and operations research strategies, and mission scenarios. Major results are presented.
Energy-aware virtual network embedding in flexi-grid networks.
Lin, Rongping; Luo, Shan; Wang, Haoran; Wang, Sheng
2017-11-27
Network virtualization technology has been proposed to allow multiple heterogeneous virtual networks (VNs) to coexist on a shared substrate network, which increases the utilization of the substrate network. Efficiently mapping VNs on the substrate network is a major challenge on account of the VN embedding (VNE) problem. Meanwhile, energy efficiency has been widely considered in the network design in terms of operation expenses and the ecological awareness. In this paper, we aim to solve the energy-aware VNE problem in flexi-grid optical networks. We provide an integer linear programming (ILP) formulation to minimize the electricity cost of each arriving VN request. We also propose a polynomial-time heuristic algorithm where virtual links are embedded sequentially to keep a reasonable acceptance ratio and maintain a low electricity cost. Numerical results show that the heuristic algorithm performs closely to the ILP for a small size network, and we also demonstrate its applicability to larger networks.
Inversion for the driving forces of plate tectonics
NASA Technical Reports Server (NTRS)
Richardson, R. M.
1983-01-01
Inverse modeling techniques have been applied to the problem of determining the roles of various forces that may drive and resist plate tectonic motions. Separate linear inverse problems have been solved to find the best fitting pole of rotation for finite element grid point velocities and to find the best combination of force models to fit the observed relative plate velocities for the earth's twelve major plates using the generalized inverse operator. Variance-covariance data on plate motion have also been included. Results emphasize the relative importance of ridge push forces in the driving mechanism. Convergent margin forces are smaller by at least a factor of two, and perhaps by as much as a factor of twenty. Slab pull, apparently, is poorly transmitted to the surface plate as a driving force. Drag forces at the base of the plate are smaller than ridge push forces, although the sign of the force remains in question.
Chen, Jeannie; Shabot, M. Michael; LoBue, Mark
2003-01-01
Prior attempts to interface ICU Clinical Information Systems (CIS) to Pharmacy systems have been less than successful. The major problem is that in ICUs, medications frequently have to be administered and charted in the CIS Medication Administration Record (MAR) before pharmacists can enter them into the Pharmacy system. When the Pharmacy system belatedly sends medication orders to the CIS MAR, this may create duplicate entries for medications that ICU nurses have had to enter manually to chart doses actually given. The authors have implemented a real time interface between a Computerized Physician Order Entry (CPOE) system and a CIS operating in ten ICUs that solves this problem. The interface transfers new medication orders including order details and alerts directly to the CIS Medication Administration Record (MAR), where they are immediately available for nurse charting. PMID:14728315
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, M.K.
1994-06-01
The United States Department of Energy (DOE) faces the major task of cleaning up hundreds of waste sites across the nation, which will require completion of a large number of remedial investigation/feasibility studies (RI/FSs). The intent of each RI/FS is to characterize the waste problems and environmental conditions at the operable unit level, segment the remediation problem into manageable medium-specific and contaminant-specific pieces, define corresponding remediation objectives, and identify remedial response actions to satisfy those objectives. The RI/FS team can then identify combinations of remediation technologies that will meet the remediation objectives. Finally, the team must evaluate these remedial alternativesmore » in terms of effectiveness, implementability, cost, and acceptability. The Remedial Action Assessment System (RAAS) is being developed by Pacific Northwest Laboratory (PNL) to support DOE in this effort.« less
Interactive visualization tools for the structural biologist.
Porebski, Benjamin T; Ho, Bosco K; Buckle, Ashley M
2013-10-01
In structural biology, management of a large number of Protein Data Bank (PDB) files and raw X-ray diffraction images often presents a major organizational problem. Existing software packages that manipulate these file types were not designed for these kinds of file-management tasks. This is typically encountered when browsing through a folder of hundreds of X-ray images, with the aim of rapidly inspecting the diffraction quality of a data set. To solve this problem, a useful functionality of the Macintosh operating system (OSX) has been exploited that allows custom visualization plugins to be attached to certain file types. Software plugins have been developed for diffraction images and PDB files, which in many scenarios can save considerable time and effort. The direct visualization of diffraction images and PDB structures in the file browser can be used to identify key files of interest simply by scrolling through a list of files.
NASA Astrophysics Data System (ADS)
El Bouami, Souhail; Habak, Malek; Franz, Gérald; Velasco, Raphaël; Vantomme, Pascal
2016-10-01
Composite materials are increasingly used for structural parts in the aeronautic industries. Carbon Fiber-Reinforced Plastics (CFRP) are often used in combination with metallic materials, mostly aluminium alloys. This raises new problems in aircraft assembly. Delamination is one of these problems. In this study, CFRP/Al-Li stacks is used as experimental material for investigation effect of interaction of cutting parameters (cutting speed and feed rate) and tool geometry on delamination and thrust forces in drilling operation. A plan of experiments, based on Taguchi design method, was employed to investigate the influence of tool geometry and in particular the point angle and cutting parameters on delamination and axial effort. The experimental results demonstrate that the feed rate is the major parameter and the importance of tool point angle in delamination and thrust forces in the stacks were shown.
Rose, Alan G
2003-01-01
This study aims to examine the autopsy-determined principal and proximate causes of death in 25 patients aged 20 years or younger who died during the 10-year period from 1990 to 1999 after receiving an organ transplant at the University of Minnesota/Fairview-University Medical Center. The autopsy records of this institution were examined for organ transplant recipients who were aged 20 years or younger at the time of their death. In each case, after review of the clinical and pathological data, the principle cause of death (PCOD), as well as the proximate cause of death (PXCOD) were noted. A total of 25 recipient patients were identified (five heart, five lung, five kidney and 10 liver transplants). Seven patients died 30 days or less post-operatively and 18 died thereafter. The following categories of PCOD were encountered: operative/technical complications 28%, most (6/7) being associated with liver transplantation. Infection (24%) and chronic rejection (12%) were other important PCOD. Respiratory complications accounted for 47% of the PCOD. The following categories of PXCOD were noted: technical problems 16%, pulmonary pathology 24%, miscellaneous 32%, acute rejection 4% and nil 20%. This study revealed that technical problems in liver transplants were an important PCOD; respiratory complications and chronic rejection were additional major causes of mortality in this young age group of transplant recipients. Pulmonary pathology and technical problems were the commonest specific groups contributing to the PXCOD.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zheng, L.; Wilson, T.H.; Shumaker, R.C.
1993-08-01
Seismic interpretations of the Granny Creek oil field in West Virginia suggest the presence of numerous small-scale fracture zones and faults. Seismic disruptions interpreted as faults and/or fracture zones are represented by abrupt reflection offsets, local amplitude reductions, and waveform changes. These features are enhanced through reprocessing, and the majority of the improvements to the data result from the surface consistent application of zero-phase deconvolution. Reprocessing yields a 20% improvement of resolution. Seismic interpretations of these features as small faults and fracture zones are supported by nearby offset vertical seismic profiles and by their proximity to wells between which directmore » communication occurs during waterflooding. Four sets of faults are interpreted based on subsurface and seismic data. Direct interwell communication is interpreted to be associated only with a northeast-trending set of faults, which are believed to have detached structural origins. Subsequent reactivation of deeper basement faults may have opened fractures along this trend. These faults have a limited effect on primary production, but cause many well-communication problems and reduce secondary production. Seismic detection of these zones is important to the economic and effective design of secondary recovery operations, because direct well communication often results in significant reduction of sweep efficiency during waterflooding. Prior information about the location of these zones would allow secondary recovery operations to avoid potential problem areas and increase oil recovery.« less
Analysis of junior high school students' attempt to solve a linear inequality problem
NASA Astrophysics Data System (ADS)
Taqiyuddin, Muhammad; Sumiaty, Encum; Jupri, Al
2017-08-01
Linear inequality is one of fundamental subjects within junior high school mathematics curricula. Several studies have been conducted to asses students' perform on linear inequality. However, it can hardly be found that linear inequality problems are in the form of "ax + b < dx + e" with "a, d ≠ 0", and "a ≠ d" as it can be seen on the textbook used by Indonesian students and several studies. This condition leads to the research questions concerning students' attempt on solving a simple linear inequality problem in this form. In order to do so, the written test was administered to 58 students from two schools in Bandung followed by interviews. The other sources of the data are from teachers' interview and mathematics books used by students. After that, the constant comparative method was used to analyse the data. The result shows that the majority approached the question by doing algebraic operations. Interestingly, most of them did it incorrectly. In contrast, algebraic operations were correctly used by some of them. Moreover, the others performed expected-numbers solution, rewriting the question, translating the inequality into words, and blank answer. Furthermore, we found that there is no one who was conscious of the existence of all-numbers solution. It was found that this condition is reasonably due to how little the learning components concern about why a procedure of solving a linear inequality works and possibilities of linear inequality solution.
NASA Astrophysics Data System (ADS)
Su, Zhi-xin; Xia, Guo-ping; Chen, Ming-yuan
2011-11-01
In this paper, we define various induced intuitionistic fuzzy aggregation operators, including induced intuitionistic fuzzy ordered weighted averaging (OWA) operator, induced intuitionistic fuzzy hybrid averaging (I-IFHA) operator, induced interval-valued intuitionistic fuzzy OWA operator, and induced interval-valued intuitionistic fuzzy hybrid averaging (I-IIFHA) operator. We also establish various properties of these operators. And then, an approach based on I-IFHA operator and intuitionistic fuzzy weighted averaging (WA) operator is developed to solve multi-attribute group decision-making (MAGDM) problems. In such problems, attribute weights and the decision makers' (DMs') weights are real numbers and attribute values provided by the DMs are intuitionistic fuzzy numbers (IFNs), and an approach based on I-IIFHA operator and interval-valued intuitionistic fuzzy WA operator is developed to solve MAGDM problems where the attribute values provided by the DMs are interval-valued IFNs. Furthermore, induced intuitionistic fuzzy hybrid geometric operator and induced interval-valued intuitionistic fuzzy hybrid geometric operator are proposed. Finally, a numerical example is presented to illustrate the developed approaches.
NASA Astrophysics Data System (ADS)
Feehan, Paul M. N.
2017-09-01
We prove existence of solutions to boundary value problems and obstacle problems for degenerate-elliptic, linear, second-order partial differential operators with partial Dirichlet boundary conditions using a new version of the Perron method. The elliptic operators considered have a degeneracy along a portion of the domain boundary which is similar to the degeneracy of a model linear operator identified by Daskalopoulos and Hamilton [9] in their study of the porous medium equation or the degeneracy of the Heston operator [21] in mathematical finance. Existence of a solution to the partial Dirichlet problem on a half-ball, where the operator becomes degenerate on the flat boundary and a Dirichlet condition is only imposed on the spherical boundary, provides the key additional ingredient required for our Perron method. Surprisingly, proving existence of a solution to this partial Dirichlet problem with ;mixed; boundary conditions on a half-ball is more challenging than one might expect. Due to the difficulty in developing a global Schauder estimate and due to compatibility conditions arising where the ;degenerate; and ;non-degenerate boundaries; touch, one cannot directly apply the continuity or approximate solution methods. However, in dimension two, there is a holomorphic map from the half-disk onto the infinite strip in the complex plane and one can extend this definition to higher dimensions to give a diffeomorphism from the half-ball onto the infinite ;slab;. The solution to the partial Dirichlet problem on the half-ball can thus be converted to a partial Dirichlet problem on the slab, albeit for an operator which now has exponentially growing coefficients. The required Schauder regularity theory and existence of a solution to the partial Dirichlet problem on the slab can nevertheless be obtained using previous work of the author and C. Pop [16]. Our Perron method relies on weak and strong maximum principles for degenerate-elliptic operators, concepts of continuous subsolutions and supersolutions for boundary value and obstacle problems for degenerate-elliptic operators, and maximum and comparison principle estimates previously developed by the author [13].
Sareen, Jitender; Cox, Brian J; Afifi, Tracie O; Stein, Murray B; Belik, Shay-Lee; Meadows, Graham; Asmundson, Gordon J G
2007-07-01
Although military personnel are trained for combat and peacekeeping operations, accumulating evidence indicates that deployment-related exposure to traumatic events is associated with mental health problems and mental health service use. To examine the relationships between combat and peacekeeping operations and the prevalence of mental disorders, self-perceived need for mental health care, mental health service use, and suicidality. Cross-sectional, population-based survey. Canadian military. A total of 8441 currently active military personnel (aged 16-54 years). The DSM-IV mental disorders (major depressive disorder, posttraumatic stress disorder, generalized anxiety disorder, panic disorder, social phobia, and alcohol dependence) were assessed using the World Mental Health version of the World Health Organization Composite International Diagnostic Interview, a fully structured lay-administered psychiatric interview. The survey included validated measures of self-perceived need for mental health treatment, mental health service use, and suicidal ideation. Lifetime exposure to peacekeeping and combat operations and witnessing atrocities or massacres (ie, mutilated bodies or mass killings) were assessed. The prevalences of any past-year mental disorder assessed in the survey and self-perceived need for care were 14.9% and 23.2%, respectively. Most individuals meeting the criteria for a mental disorder diagnosis did not use any mental health services. Deployment to combat operations and witnessing atrocities were associated with increased prevalence of mental disorders and perceived need for care. After adjusting for the effects of exposure to combat and witnessing atrocities, deployment to peacekeeping operations was not associated with increased prevalence of mental disorders. This is the first study to use a representative sample of active military personnel to examine the relationship between deployment-related experiences and mental health problems. It provides evidence of a positive association between combat exposure and witnessing atrocities and mental disorders and self-perceived need for treatment.
Problems faced and coping strategies used by adolescents with mentally ill parents in Delhi.
George, Shoba; Shaiju, Bindu; Sharma, Veena
2012-01-01
The present study was conducted to assess the problems faced by adolescents whose parents suffer from major mental illness at selected mental health institutes of Delhi. The objectives also included assessment of the coping strategies of the adolescents in dealing with these problems. The Stuart Stress Adaptation Model of Psychiatric Nursing Care was used as the conceptual framework. A descriptive survey approach with cross-sectional design was used in the study. A structured interview schedule was prepared. Purposive non-probability sampling technique was employed to interview 50 adolescents whose parents suffer from major mental illness. Data gathered was analysed and interpreted using both descriptive and inferential statistics. The study showed that majority of the adolescents had moderate problems as a result of their parent's mental illness. Area-wise analysis of the problems revealed that the highest problems faced were in family relationship and support and majority of the adolescents used maladaptive coping strategies. A set of guidelines on effective coping strategies was disseminated to these adolescents.
Top-up operation at Pohang Light Source-II
NASA Astrophysics Data System (ADS)
Hwang, I.; Huang, J. Y.; Kim, M.; Lee, B.-J.; Kim, C.; Choi, J.-Y.; Kim, M.-H.; Lee, H. S.; Moon, D.; Lee, E. H.; Kim, D.-E.; Nam, S. H.; Shin, S.; Cho, Moohyun
2014-05-01
After three years of upgrading work, PLS-II (S. Shin, Commissioning of the PLS-II, JINST, January 2013) is now successfully operating. The top-up operation of the 3 GeV linear accelerator had to be delayed because of some challenges encountered, and PLS-II was run in decay mode at the beginning in March 2012. The main difficulties encountered in the top-up operation of PLS-II are different levels between the linear accelerator and the storage ring, the 14 narrow gap in-vacuum undulators in operation, and the full energy injection by 3 GeV linear accelerator. Large vertical emittance and energy jitter of the linac were the major obstacles that called for careful control of injected beam to reduce beam loss in the storage ring during injection. The following measures were taken to resolve these problems: (1) The high resolution Libera BPM (see http://www.i-tech.si) was implemented to measure the beam trajectory and energy. (2) Three slit systems were installed to filter the beam edge. (3) De-Qing circuit was applied to the modulator system to improve the energy stability of injected beam. As a result, the radiation by beam loss during injection is reduced drastically, and the top-up mode has been successfully operating since 19th March 2013. In this paper, we describe the experimental results of the PLS-II top-up operation and the improvement plan.
1981-11-01
OPERATIONS MANAGEMENT S. TYPE OF REPORT A PERIOD COVERED TEST OF THE USE OF THE WHITE AMUR FOR CONTROL OF Report 2 of a series PROBLEM AQUATIC PLANTS...111. 1981. "Large-Scale Operations Management Test of the Use of the White Amur for Control of Problem Aquatic Plants; Report 2, First Year Poststock...Al 3 LARGE-SCALE OPERATIONS MANAGEMENT TEST OF USE OF THE WHITE AMUR FOR CONTROL OF PROBLEM AQUATIC PLANTS A MODEL FOR EVALUATION OF
Sroyhin, Waranya; Thiamwisai, Lumphung; Surit, Pattama; Chowchuen, Bowornslip
2016-08-01
The operating room Srinagarind hospital handles most cases that require surgical repair including cleft lip and palate patients. The average number of patients undergone surgical correction has risen to 216 in 2016 from 150 in 2014. Patients who underwent surgery, particularly infants had to be separated from family, stay in restricted place, abstaining from food and water, these create stress, fear, anxiety and pain to the child and may have affected to the outcomes of the treatment. For parents and families will also are anxious, and fears about the disease and treatment, losing children, disabled children after the surgery. In addition, their concerns with complications of surgery and chance of recovery. Therefore, there is a need to examine the clinical problems of patients who undergo surgery for cleft lip and palate in order to provide comprehensive care. To identify problems in regards to care for patients with cleft lip and palate, in the operating room, Srinagarind Hospital. The descriptive study was conducted involving nine departments of nursing services, Srinagarind Hospital. After the consideration of human ethic, both quantitative and qualitative data were collected based on The Center for Advance Nursing Practice Model through the following four stimulators: 1) reviewed 30 patients medical records; 2) reviewed four related literatures; 3) surveyed nurses opinion towards health condition’s and the effects of the 10 families with cleft lip and palate; and 4) interviewed ten mothers and families towards the health of cleft lip and palate children. The interviews obtained 15-20 minutes per case with a total of eight months of collecting data (June 2015 - January 2016). The quantitative data were analyzed using percentage and content analyses were used with qualitative data. There were four cases underwent operation for cleft lip and palate (40%) four cases underwent age 3-6 months and 10-18 month four cases underwent age 3-6 months and 10-18 month(40%) which included six male (60%) and ten female caregivers (100%), four of which aged older than 50 years (40%), three cases were each a farmer and housekeeper. For nurses, the majority aged between 40-44 years, nine of which had bachelor degree (90%). The results from nurses’ survey found that the caregiver concerned about patients’ hunger, and surgical complications such as hypothermia, pressure ulcers from operation, postural, bleeding after operation which need additional operation, something stuck in operating wound, and infected wound. The interviewing with the caregiver and mother towards patient health conditions found that the caregivers concerned about anesthetic procedure, wound separation and infection, and the operating cost. Most patients felt fear of fainting and thirsty since food and water discontinuation. Based on the literature review, the problems included the caregivers’ concerns about surgical complications which these were similar to those results from the nurses’ survey. Problems for care of patients with cleft lip and palate in the operating room in Srinagarind Hospital were: 1) concerns about the operation and cost of treatment, 2) surgical complication both immediate and long-term complications, 3) concerns about pain and wound infection. Such evidence would be used in the development plan towards nursing system for cleft lip and palate patients in the operating room.
Human Factors of Remotely Piloted Aircraft
NASA Technical Reports Server (NTRS)
Hobbs, Alan Neville
2014-01-01
The civilian use of remotely piloted, or unmanned aircraft is expected to increase rapidly in the years ahead. Despite being referred to as unmanned some of the major challenges confronting this emerging sector relate to human factors. As unmanned aircraft systems (UAS) are introduced into civil airspace, a failure to adequately consider human factors could result in preventable accidents that may not only result in loss of life, but may also undermine public confidence in remotely piloted operations. Key issues include pilot situational awareness, collision avoidance in the absence of an out-the-window view, the effects of time delays in communication and control systems, control handovers, the challenges of very long duration flights, and the design of the control station. Problems have included poor physical layout of controls, non-intuitive automation interfaces, an over-reliance on text displays, and complicated sequences of menu selection to perform routine tasks. Some of the interface problems may have been prevented had an existing regulation or cockpit design principle been applied. In other cases, the design problems may indicate a lack of suitable guidance material.
Efficient convex-elastic net algorithm to solve the Euclidean traveling salesman problem.
Al-Mulhem, M; Al-Maghrabi, T
1998-01-01
This paper describes a hybrid algorithm that combines an adaptive-type neural network algorithm and a nondeterministic iterative algorithm to solve the Euclidean traveling salesman problem (E-TSP). It begins with a brief introduction to the TSP and the E-TSP. Then, it presents the proposed algorithm with its two major components: the convex-elastic net (CEN) algorithm and the nondeterministic iterative improvement (NII) algorithm. These two algorithms are combined into the efficient convex-elastic net (ECEN) algorithm. The CEN algorithm integrates the convex-hull property and elastic net algorithm to generate an initial tour for the E-TSP. The NII algorithm uses two rearrangement operators to improve the initial tour given by the CEN algorithm. The paper presents simulation results for two instances of E-TSP: randomly generated tours and tours for well-known problems in the literature. Experimental results are given to show that the proposed algorithm ran find the nearly optimal solution for the E-TSP that outperform many similar algorithms reported in the literature. The paper concludes with the advantages of the new algorithm and possible extensions.
NASA Technical Reports Server (NTRS)
Wunsche, A.
1993-01-01
The eigenvalue problem of the operator a + zeta(boson creation operator) is solved for arbitrarily complex zeta by applying a nonunitary operator to the vacuum state. This nonunitary approach is compared with the unitary approach leading for the absolute value of zeta less than 1 to squeezed coherent states.
Operant Variability: Some Random Thoughts
ERIC Educational Resources Information Center
Marr, M. Jackson
2012-01-01
Barba's (2012) paper is a serious and thoughtful analysis of a vexing problem in behavior analysis: Just what should count as an operant class and how do people know? The slippery issue of a "generalized operant" or functional response class illustrates one aspect of this problem, and "variation" or "novelty" as an operant appears to fall into…
McGinnis, Molly A; Houchins-Juárez, Nealetta; McDaniel, Jill L; Kennedy, Craig H
2010-01-01
Three participants whose problem behavior was maintained by contingent attention were exposed to 45-min presessions in which attention was withheld, provided on a fixed-time (FT) 15-s schedule, or provided on an FT 120-s schedule. Following each presession, participants were then tested in a 15-min session similar to the social attention condition of an analogue functional analysis. The results showed establishing operation conditions increased problem behavior during tests and that abolishing operation conditions decreased problem behavior during tests. PMID:20808502
McGinnis, Molly A; Houchins-Juárez, Nealetta; McDaniel, Jill L; Kennedy, Craig H
2010-03-01
Three participants whose problem behavior was maintained by contingent attention were exposed to 45-min presessions in which attention was withheld, provided on a fixed-time (FT) 15-s schedule, or provided on an FT 120-s schedule. Following each presession, participants were then tested in a 15-min session similar to the social attention condition of an analogue functional analysis. The results showed establishing operation conditions increased problem behavior during tests and that abolishing operation conditions decreased problem behavior during tests.
The Problem of Space in Soviet Operational Art.
1988-01-01
problems of military science and military art , and the improvement of the material-technical base of the Soviet Army and Navy and their structures.2 If...140-RI94 150 THE PROBLEM OF SPACE IN SOVIET OPERATIONAL ART (U) ARMY i/I COMBINED ARMS CENTER FORT LEAVENMORTN KS SOVIET ARMY UNCLSSIIEDSTUDIES OFFICE...SUB-GROUP oPGR*7D/.J1 ? So/Ie7 CE’ge*4 SrWp,-v=I S THE PROBLEM OF SPACE IN SOVIET OPERATIONAL ART by Dr. Jacob W. Kipp Soviet Army Studies Office S U
Regulations as Prevention Strategies for Shiftwork Problems.
Jeppesen; Bøggild; Larsen
1997-07-01
The study examines how the Danish system of regulations stemming from collective agreements and legislation and its associated participatory structures operate at the local level in relation to shiftwork and health and safety issues in a regional hospital system consisting of seven hospitals. The study analyzed ward reports of each employee's employment and working hours, local agreements about working time for deviations from legislation, and accounts from meetings in Co-operation Committees and Health and Safety Committees with respect to shiftwork issues from 1980 to 1994. The results showed that part-time employment, especially for those working on fixed evening and night shifts, was a dominant feature in the shiftwork arrangements. A majority of wards were found to have mixtures of employees working rotating or fixed shifts. Each hospital had local agreements that extended the number of work days between periods with days off and reduced the daily resting period to its minimum. None of the meetings of the Health and Safety Committees dealt with shiftwork, and when shiftwork and working time were on the agendas of the Co-operation Committees, health and safety aspects did not feature in the conclusions. The absence of consideration of health and safety aspects is discussed in relation to the uncertainty of the general regulatory principles for work organization and scheduling. The paper concludes that in order to utilize the potential af the participatory structures in developing prevention strategies for shiftwork problems, it is important to clarify responsibilities and cooperation between the two participatory committees.
A new look at the position operator in quantum theory
NASA Astrophysics Data System (ADS)
Lev, F. M.
2015-01-01
The postulate that coordinate and momentum representations are related to each other by the Fourier transform has been accepted from the beginning of quantum theory by analogy with classical electrodynamics. As a consequence, an inevitable effect in standard theory is the wave packet spreading (WPS) of the photon coordinate wave function in directions perpendicular to the photon momentum. This leads to the following paradoxes: if the major part of photons emitted by stars are in wave packet states (what is the most probable scenario) then we should see not separate stars but only an almost continuous background from all stars; no anisotropy of the CMB radiation should be observable; data on gamma-ray bursts, signals from directional radio antennas (in particular, in experiments on Shapiro delay) and signals from pulsars show no signs of WPS. In addition, a problem arises why there are no signs of WPS for protons in the LHC ring. We argue that the above postulate is based neither on strong theoretical arguments nor on experimental data and propose a new consistent definition of the position operator. Then WPS in directions perpendicular to the particle momentum is absent and the paradoxes are resolved. Different components of the new position operator do not commute with each other and, as a consequence, there is no wave function in coordinate representation. Implications of the results for entanglement, quantum locality and the problem of time in quantum theory are discussed.
Study of research and development requirements of small gas-turbine combustors
NASA Technical Reports Server (NTRS)
Demetri, E. P.; Topping, R. F.; Wilson, R. P., Jr.
1980-01-01
A survey is presented of the major small-engine manufacturers and governmental users. A consensus was undertaken regarding small-combustor requirements. The results presented are based on an evaluation of the information obtained in the course of the study. The current status of small-combustor technology is reviewed. The principal problems lie in liner cooling, fuel injection, part-power performance, and ignition. Projections of future engine requirements and their effect on the combustor are discussed. The major changes anticipated are significant increases in operating pressure and temperature levels and greater capability of using heavier alternative fuels. All aspects of combustor design are affected, but the principal impact is on liner durability. An R&D plan which addresses the critical combustor needs is described. The plan consists of 15 recommended programs for achieving necessary advances in the areas of liner thermal design, primary-zone performance, fuel injection, dilution, analytical modeling, and alternative-fuel utilization.
NASA Astrophysics Data System (ADS)
Liu, Shuang; Liu, Fei; Hu, Shaohua; Yin, Zhenbiao
The major power information of the main transmission system in machine tools (MTSMT) during machining process includes effective output power (i.e. cutting power), input power and power loss from the mechanical transmission system, and the main motor power loss. These information are easy to obtain in the lab but difficult to evaluate in a manufacturing process. To solve this problem, a separation method is proposed here to extract the MTSMT power information during machining process. In this method, the energy flow and the mathematical models of major power information of MTSMT during the machining process are set up first. Based on the mathematical models and the basic data tables obtained from experiments, the above mentioned power information during machining process can be separated just by measuring the real time total input power of the spindle motor. The operation program of this method is also given.
Materials and structural aspects of advanced gas-turbine helicopter engines
NASA Technical Reports Server (NTRS)
Freche, J. C.; Acurio, J.
1979-01-01
The key to improved helicopter gas turbine engine performance lies in the development of advanced materials and advanced structural and design concepts. The modification of the low temperature components of helicopter engines (such as the inlet particle separator), the introduction of composites for use in the engine front frame, the development of advanced materials with increased use-temperature capability for the engine hot section, can result in improved performance and/or decreased engine maintenance cost. A major emphasis in helicopter engine design is the ability to design to meet a required lifetime. This, in turn, requires that the interrelated aspects of higher operating temperatures and pressures, cooling concepts, and environmental protection schemes be integrated into component design. The major material advances, coatings, and design life-prediction techniques pertinent to helicopter engines are reviewed; the current state-of-the-art is identified; and when appropriate, progress, problems, and future directions are assessed.
Readiness: observations and comments from a medical team deployment.
Popper, S E; Noble, D E; Mason, L J; Schaffer, L A; Glover, J G; Barkley, M S
1997-02-01
The evolving strategy of the United States in dealing with the changing world order calls for a force structure capable of fighting and winning two nearly simultaneous major regional conflicts and conducting a range of other military operations. Readiness is a key factor in this new strategy. Consequently, major paradigm shifts are occurring within the Air Force Medical Service. Maintaining current and accurate medical records on personnel to meet deployment requirements is a significant challenge. Historically, time and resources are consumed determining the deployability of troops prior to a deployment. This adds to the cost of doing business and increases the time required to clear the deploying team, even though there is an established process to avoid these very problems. The experience of a recent medical team deployment to Bosnia is discussed. Future directions given the implementation of TRI-CARE, the Preventive Health Assessment Program, and the Strategic Health Resourcing Plan are also considered.
Sensibility study in a flexible job shop scheduling problem
NASA Astrophysics Data System (ADS)
Curralo, Ana; Pereira, Ana I.; Barbosa, José; Leitão, Paulo
2013-10-01
This paper proposes the impact assessment of the jobs order in the optimal time of operations in a Flexible Job Shop Scheduling Problem. In this work a real assembly cell was studied: the AIP-PRIMECA cell at the Université de Valenciennes et du Hainaut-Cambrésis, in France, which is considered as a Flexible Job Shop problem. The problem consists in finding the machines operations schedule, taking into account the precedence constraints. The main objective is to minimize the batch makespan, i.e. the finish time of the last operation completed in the schedule. Shortly, the present study consists in evaluating if the jobs order affects the optimal time of the operations schedule. The genetic algorithm was used to solve the optimization problem. As a conclusion, it's assessed that the jobs order influence the optimal time.
Operational considerations for the airship in short-haul transportation
NASA Technical Reports Server (NTRS)
Walker, C. D.
1975-01-01
The airship's problems and the possibilities for their solution in a short-haul transportation environment are surveyed. The problems are derived from both past experience and envisioned operation. Problems relative to both fully buoyant and semi-buoyant configurations are considered and their origins in principle discussed. Also addressed in this paper are the state-of-the-art technologies with the potential of providing answers to the airship's operational difficulties.
Mode Transitions in Glass Cockpit Aircraft: Results of a Field Study
NASA Technical Reports Server (NTRS)
Degani, Asaf; Kirlik, Alex; Shafto, Michael (Technical Monitor)
1995-01-01
One consequence of increased levels of automation in complex control systems is the presence of modes. A mode is a particular configuration of a control system that defines how human command inputs are interpreted. In complex systems, modes also often determine a specific allocation of control authority between the human and automated systems. Even in simple static devices (e.g., electronic watches, word processors), the presence of modes has been found to cause problems in either-the acquisition or production of skilled performance. Many of these problems arise due to the fact that the selection of a mode causes device behavior to be mediated by hidden internal state information. For these simple systems, many of these interaction problems can be solved by the design of appropriate feedback to communicate internal state information to the human operator. In complex dynamic systems, however, the design issues associated with modes seem to trancend the problem of merely communicating internal state information via displayed feedback. In complex supervisory control systems (e.g., aircraft, spacecraft, military command and control), a key function of modes is the selection of a particular configuration of control authority between the human operator and automated control systems. One mode may result in full manual control, another may result in a mix of manual and automatic control, while a third may result in full automatic control over the entire system. The human operator selects an appropriate mode as a function of current goals, operating conditions, and operating procedures. Thus, the operator is put in a position of essentially trying to control two coupled dynamic systems: the target system itself, and also a highly complex suite of automation controlling the target system. From a historical perspective, it should probably not come as a surprise that very little information is available to guide the design of mode-oriented control systems. The topic of function allocation (i.e., the proper division of control authority among human and computer) has a long history in human-machine systems research. Although this research has produced some relevant guidelines, a design approach capable of defining appropriate allocations of control function between the human and automation is not yet available. As a result, the function allocation decision itself has been allocated to the operator, to be performed in real-time, in the operation of mode-oriented control systems. A variety of documented aircraft accidents and incidents suggest that the real-time selection and monitoring of control modes is a weak link in the effective operation of complex supervisory control systems. Research in human-machine systems and human-computer interaction has barely scraped the surface of the problem of understanding how operators manage this task.The purpose of this paper is to present the results of a field study which examined how operators manage mode selection in a complex supervisory control system. Data on mode engagements using the Boeing B757/767 auto-flight system were collected during approach and descent into four major airports in the East Coast of the United States. Protocols documenting mode selection, automatic mode changes, pilot actions, quantitative records of flight-path variables, and verbal reports during and after mode engagements were collected by an observer from the jumpseat. Observations were conducted on two typical trips between three airports. Each trip was be replicated 11 times, which yielded a total of 22 trips and 66 legs on which data were collected. All data collected concerned the same flight numbers, and therefore, the same time of day, same type of aircraft, and identical operational environments (e.g., ATC facilities, weather patterns, traffic flow etc.)
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.
1984-06-01
RD-Rl45 988 AQUATIC PLANT CONTROL RESEARCH PROGRAM LARGE-SCALE 1/2 OPERATIONS MANAGEMENT ..(U) ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS...REPORT A-78-2 LARGE-SCALE OPERATIONS MANAGEMENT TEST OF USE OF THE WHITE AMUR FOR -, CONTROL OF PROBLEM AQUATIC PLANTS Report 5 SYNTHESIS REPORT bv Andrew...Corps of Engineers Washington, DC 20314 84 0,_1 oil.. LARGE-SCALE OPERATIONS MANAGEMENT TEST OF USE OF THE WHITE AMUR FOR CONTROL OF PROBLEM AQUATIC
The connection between water and energy in cities: a review.
Kenway, S J; Lant, P A; Priestley, A; Daniels, P
2011-01-01
We have only rudimentary understanding of the complex and pervasive connections between water and energy in cities. As water security now threatens energy and economic security, this is a major omission. Understanding the water-energy nexus is necessary if we want to contribute to solving water and energy issues simultaneously; if we want to stop moving problems from one resource dimension to another. This is particularly relevant in the Australian context where energy use for water supplies is forecast to rapidly escalate, growing around 300% from 2007 levels, by 2030. This paper presents a literature review with an aim of characterising the research to date with a particular focus on cities, the major centres of consumption and growth. It systematically analyses a wide range of papers and summarises the diverse objectives, dimensions, and scale of the research to-date together with knowledge gaps. There are many major gaps. These include energy use associated with water in industrial and commercial operations as well as socio-political perspectives. A major gap is the lack of a unifying theoretical framework and consistent methodology for analysis. This is considered a prerequisite for quantitative trans-city comparisons.
Takeda, Hiroshi; Matsumura, Yasushi; Nakagawa, Katsuhiko; Teratani, Tadamasa; Qiyan, Zhang; Kusuoka, Hideo; Matsuoka, Masami
2004-01-01
To share healthcare information and to promote cooperation among healthcare providers and customers (patients) under computerized network environment, a non-profit organization (NPO), named as OCHIS, was established at Osaka, Japan in 2003. Since security and confidentiality issues on the Internet have been major concerns in the OCHIS, the system has been based on healthcare public key infrastructure (HPKI), and found that there remained problems to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority by contracting with the Ministry of Economics and Trading Industries in 2003. This paper describes the experimental design with NPO and the results of the study concerning message security and HPKI. The developed system has been operated practically in Osaka urban area.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mancini, T.R.; Chaturvedi, L.N.; Gebhard, T.G.
A demonstration project to heat the Senior Citizens Center at Truth or Consequences, New Mexico with geothermal waters is described. There were three phases to the project: Phase I - design and permitting; Phase II - installation of the heating system and well drilling; and Phase III - operation of the system. All three phases went well and there was only one major problem encountered. This was that the well which was drilled to serve as the geothermal source was dry. This could not have been anticipated and there was, as a contingency plan, the option of using an existingmore » sump in the Teen Center adjacent to the Senior Citizens Center as the geothermal source. The system was made operational in August of 1981 and has virtually supplied all of the heat to the Senior Citizens Center during this winter.« less
NASA Astrophysics Data System (ADS)
Liebenberg, Keagen; Smit, Ansie; Coetzee, Serena; Kijko, Andrzej
2017-08-01
The majority of seismic activity in South Africa is related to extensive mining operations, usually in close proximity to densely populated areas where a relatively weak seismic event could cause damage. Despite a significant decrease in mining operations in the Witwatersrand area, the number of seismic events appears to be increasing and is attributed to the acid mine drainage problem. The increased seismicity is raising concern amongst disaster management centres and in the insurance industry. A better understanding is required of the vulnerability and the size of the potential loss of people and infrastructure in densely populated Johannesburg and its surrounding areas. Results of a deterministic seismic risk, vulnerability, and loss assessment are presented by making use of a geographic information system (GIS). The results illustrate the benefits of using GIS and contribute to a better understanding of the risk, which can assist in improving disaster preparedness.
NASA Technical Reports Server (NTRS)
Abbott, T. S.; Moen, G. C.; Person, L. H., Jr.; Keyser, G. L., Jr.; Yenni, K. R.; Garren, J. F., Jr.
1980-01-01
Traffic symbology was encoded to provide additional information concerning the traffic, which was displayed on the pilot's electronic horizontal situation indicators (EHSI). A research airplane representing an advanced operational environment was used to assess the benefit of coded traffic symbology in a realistic work-load environment. Traffic scenarios, involving both conflict-free and conflict situations, were employed. Subjective pilot commentary was obtained through the use of a questionnaire and extensive pilot debriefings. These results grouped conveniently under two categories: display factors and task performance. A major item under the display factor category was the problem of display clutter. The primary contributors to clutter were the use of large map-scale factors, the use of traffic data blocks, and the presentation of more than a few airplanes. In terms of task performance, the cockpit-displayed traffic information was found to provide excellent overall situation awareness. Additionally, mile separation prescribed during these tests.
Innovative test method for the estimation of the foaming tendency of substrates for biogas plants.
Moeller, Lucie; Eismann, Frank; Wißmann, Daniel; Nägele, Hans-Joachim; Zielonka, Simon; Müller, Roland A; Zehnsdorf, Andreas
2015-07-01
Excessive foaming in anaerobic digestion occurs at many biogas plants and can cause problems including plugged gas pipes. Unfortunately, the majority of biogas plant operators are unable to identify the causes of foaming in their biogas reactor. The occurrence of foaming is often related to the chemical composition of substrates fed to the reactor. The consistency of the digestate itself is also a crucial part of the foam formation process. Thus, no specific recommendations concerning substrates can be given in order to prevent foam formation in biogas plants. The safest way to avoid foaming is to test the foaming tendency of substrates on-site. A possible solution is offered by an innovative foaming test. With the help of this tool, biogas plant operators can evaluate the foaming disposition of new substrates prior to use in order to adjust the composition of substrate mixes. Copyright © 2015 Elsevier Ltd. All rights reserved.
High temperature superconductors for magnetic suspension applications
NASA Technical Reports Server (NTRS)
Mcmichael, C. K.; Cooley, R. S.; Chen, Q. Y.; Ma, K. B.; Lamb, M. A.; Meng, R. L.; Chu, C. W.; Chu, W. K.
1994-01-01
High temperature superconductors (HTS) hold the promise for applications in magnetic levitation bearings, vibration damping, and torque coupling. Traditional magnetic suspension systems require active feedback and vibration controls in which power consumption and low frequency vibration are among the major engineering concerns. HTS materials have been demonstrated to be an enabling approach towards such problems due to their flux trapping properties. In our laboratory at TCSUH, we have been conducting a series of experiments to explore various mechanical applications using HTS. We have constructed a 30 lb. model flywheel levitated by a hybrid superconducting magnetic bearing (HSMB). We are also developing a levitated and vibration-dampled platform for high precision instrumentation. These applications would be ideal for space usages where ambient temperature is adequate for HTS to operate properly under greatly reduced cryogenic requirements. We will give a general overview of these potential applications and discuss the operating principles of the HTS devices we have developed.
Electrocatalytic activity of ZnS nanoparticles in direct ethanol fuel cells
NASA Astrophysics Data System (ADS)
Bredol, Michael; Kaczmarek, Michał; Wiemhöfer, Hans-Dieter
2014-06-01
Low temperature fuel cells consuming ethanol without reformation would be a major step toward the use of renewable energy sources from biomass. However, the necessary electrodes and electrocatalysts still are far from being perfect and suffer from various poisoning and deactivation processes. This work describes investigations on systems using carbon/ZnS-based electrocatalysts for ethanol oxidation in complete membrane electrode assemblies (MEAs). MEAs were built on Nafion membranes with active masses prepared from ZnS nanoparticles and Vulcan carbon support. Under operation, acetic acid and acetaldehyde were identified and quantified as soluble oxidation products, whereas the amount of CO2 generated could not be quantified directly. Overall conversion efficiencies of up to 25% were estimated from cells operated over prolonged time. From polarization curves, interrupt experiments and analysis of reaction products, mass transport problems (concentration polarization) and breakthrough losses were found to be the main deficiencies of the ethanol oxidation electrodes fabricated so far.
The first Spanish space programme 1968 1974
NASA Astrophysics Data System (ADS)
Dorado, José M.
2007-06-01
This paper presents the situation of the Spanish aeronautical industry in the early 1960s, the problems suffered during the first ESRO years, the situation in 1975 as a result of the first National Space Programme (1968-1974) and the specific developments carried out within that programme: the first Spanish satellite successfully launched in 1974 (INTASAT) and the first INTA sounding rockets launched from the own Arenosillo range. This justifies the importance of that Programme for the Spanish aeronautical industry, a programme that permitted its transition to the aerospace field. In parallel, agreements with NASA led to the installation of large space ground stations in Spain operated by INTA personnel, to support major NASA space missions, and to the operation of a very active rockets range. These actions allowed Spain to have one of the largest space sectors in Europe, in those years. This paper's purpose is to find out the main reasons behind this effort.
NASA Technical Reports Server (NTRS)
Billings, Charles
1991-01-01
An overview is presented of the growth and role of automation in civil aircraft operations for both cockpit management and ground control. NASA has initiated a research program centered on furthering automation and developing a consistent and rational philosophy of human centered aircraft and air traffic control automation. Introduction of the NASA Aviation Safety Reporting System (ASRS) has proved successful in bringing together pilots and ground controllers to report incidents of operational anomalies that can then be analyzed, leading to corrective action to prevent similar reoccurrences. Attention is given to the growing trend of extensive automation in the cockpit that appears to be leading to a diminution of management control of the aircraft by the decreasing number of flight crew members. A majority of reports indicate that there is a serious mismatch between new aircraft capabilities and ATC procedures, which were designed for older aircraft. ASRS has also kept research oriented toward real problems and community needs.
NASA Technical Reports Server (NTRS)
Gentry, Gregory J.; Cover, John
2015-01-01
Nov 2, 2014 marked the completion of the 14th year of continuous human presence in space on board the International Space Station (ISS). After 42 expedition crews, over 115 assembly & utilization flights, over 180 combined Shuttle/Station, US & Russian Extravehicular Activities (EVAs), the post-Assembly-Complete ISS continues to fly and the engineering teams continue to learn from operating its systems, particularly the life support equipment. Problems with initial launch, assembly and activation of ISS elements have given way to more long term system operating trends. New issues have emerged, some with gestation periods measured in years. Major events and challenges for each U.S. Environmental Control and Life Support (ECLS) subsystem occurring during calendar years 2010 through 2014 are summarily discussed in this paper, along with look-aheads for what might be coming in the future for each U.S. ECLS subsystem.
Disposal of high-level nuclear waste above the water table in arid regions
Roseboom, Eugene H.
1983-01-01
Locating a repository in the unsaturated zone of arid regions eliminates or simplifies many of the technological problems involved in designing a repository for operation below the water table and predicting its performance. It also offers possible accessibility and ease of monitoring throughout the operational period and possible retrieval of waste long after. The risks inherent in such a repository appear to be no greater than in one located in the saturated zone; in fact, many aspects of such a repository's performance will be much easier to predict and the uncertainties will be reduced correspondingly. A major new concern would be whether future climatic changes could produce significant consequences due to possible rise of the water table or increased flux of water through the repository. If spent fuel were used as a waste form, a second new concern would be the rates of escape of gaseous iodine-129 and carbon-14 to the atmosphere.
Feasibility of touch-less control of operating room lights.
Hartmann, Florian; Schlaefer, Alexander
2013-03-01
Today's highly technical operating rooms lead to fairly complex surgical workflows where the surgeon has to interact with a number of devices, including the operating room light. Hence, ideally, the surgeon could direct the light without major disruption of his work. We studied whether a gesture tracking-based control of an automated operating room light is feasible. So far, there has been little research on control approaches for operating lights. We have implemented an exemplary setup to mimic an automated light controlled by a gesture tracking system. The setup includes a articulated arm to position the light source and an off-the-shelf RGBD camera to detect the user interaction. We assessed the tracking performance using a robot-mounted hand phantom and ran a number of tests with 18 volunteers to evaluate the potential of touch-less light control. All test persons were comfortable with using the gesture-based system and quickly learned how to move a light spot on flat surface. The hand tracking error is direction-dependent and in the range of several centimeters, with a standard deviation of less than 1 mm and up to 3.5 mm orthogonal and parallel to the finger orientation, respectively. However, the subjects had no problems following even more complex paths with a width of less than 10 cm. The average speed was 0.15 m/s, and even initially slow subjects improved over time. Gestures to initiate control can be performed in approximately 2 s. Two-thirds of the subjects considered gesture control to be simple, and a majority considered it to be rather efficient. Implementation of an automated operating room light and touch-less control using an RGBD camera for gesture tracking is feasible. The remaining tracking error does not affect smooth control, and the use of the system is intuitive even for inexperienced users.
Application of the gravity search algorithm to multi-reservoir operation optimization
NASA Astrophysics Data System (ADS)
Bozorg-Haddad, Omid; Janbaz, Mahdieh; Loáiciga, Hugo A.
2016-12-01
Complexities in river discharge, variable rainfall regime, and drought severity merit the use of advanced optimization tools in multi-reservoir operation. The gravity search algorithm (GSA) is an evolutionary optimization algorithm based on the law of gravity and mass interactions. This paper explores the GSA's efficacy for solving benchmark functions, single reservoir, and four-reservoir operation optimization problems. The GSA's solutions are compared with those of the well-known genetic algorithm (GA) in three optimization problems. The results show that the GSA's results are closer to the optimal solutions than the GA's results in minimizing the benchmark functions. The average values of the objective function equal 1.218 and 1.746 with the GSA and GA, respectively, in solving the single-reservoir hydropower operation problem. The global solution equals 1.213 for this same problem. The GSA converged to 99.97% of the global solution in its average-performing history, while the GA converged to 97% of the global solution of the four-reservoir problem. Requiring fewer parameters for algorithmic implementation and reaching the optimal solution in fewer number of functional evaluations are additional advantages of the GSA over the GA. The results of the three optimization problems demonstrate a superior performance of the GSA for optimizing general mathematical problems and the operation of reservoir systems.
NASA Technical Reports Server (NTRS)
Glaab, Louis J.; Kramer, Lynda J.; Arthur, Trey; Parrish, Russell V.; Barry, John S.
2003-01-01
Limited visibility is the single most critical factor affecting the safety and capacity of worldwide aviation operations. Synthetic Vision Systems (SVS) technology can solve this visibility problem with a visibility solution. These displays employ computer-generated terrain imagery to present 3D, perspective out-the-window scenes with sufficient information and realism to enable operations equivalent to those of a bright, clear day, regardless of weather conditions. To introduce SVS display technology into as many existing aircraft as possible, a retrofit approach was defined that employs existing HDD display capabilities for glass cockpits and HUD capabilities for the other aircraft. This retrofit approach was evaluated for typical nighttime airline operations at a major international airport. Overall, 6 evaluation pilots performed 75 research approaches, accumulating 18 hours flight time evaluating SVS display concepts that used the NASA LaRC's Boeing B-757-200 aircraft at Dallas/Fort Worth International Airport. Results from this flight test establish the SVS retrofit concept, regardless of display size, as viable for tested conditions. Future assessments need to extend evaluation of the approach to operations in an appropriate, terrain-challenged environment with daytime test conditions.
Anaerobic treatment of coconut husk liquor for biogas production.
Leitão, R C; Araújo, A M; Freitas-Neto, M A; Rosa, M F; Santaella, S T
2009-01-01
The market for coconut water causes environmental problems as it is one of the major agro-industrial solid wastes in some developing countries. With the aim of reusing the coconut husk, Embrapa developed a system for processing this raw material. During the dewatering stage Coconut Husk Liquor (CHL) is generated with chemical oxygen demand (COD) varying from 60 to 70 g/L due to high concentrations of sugars and tannins. The present study evaluated the feasibility of anaerobic treatment of CHL through Anaerobic Toxicity Assay and the operation of a lab-scale Upflow Anaerobic Sludge Blanket (UASB) reactor. Results showed that CHL can be treated through a UASB reactor operating with an OLR that reaches up to 10 kg/m3.d and that is maintained stable during the whole operation. With this operational condition, the removal efficiency was higher than 80% for COD and approximately 78% for total tannins, and biogas production was 20 m3 of biogas or 130 KWh per m3 of CHL. Seventy-five percent of the biogas composition was methane and toxicity tests demonstrated that CHL was not toxic to the methanogenic consortia. Conversely, increasing the concentration of CHL leads to increased methanogenic activity.
Contract Design: The problem of information asymmetry
Amelung, Volker E.; Juhnke, Christin
2018-01-01
Introduction: Integrated care systems are advocated as an effective method of improving the performance of healthcare systems. These systems outline a payment and care delivery model that intends to tie provider reimbursements to predefined quality metrics. Little is known about the contractual design and the main challenges of delegating “accountability” to these new kinds of organisations and/or contracts. The research question in this article focuses on how healthcare contracts can look like and which possible problems arise in designing such contracts. In this a special interest is placed on information asymmetries. Methods: A comprehensive literature review on methods of designing contracts in Integrated Care was conducted. This article is the first in a row of three that all contribute to a specific issue in designing healthcare contracts. Starting with the organisation of contracts and information asymmetries, part 2 focusses on financial options and risks and part 3 finally concludes with the question of risk management and evaluation. Results: Healthcare contracting between providers and payers will have a major impact on the overall design of future healthcare systems. If Integrated care systems or any other similar concept of care delivery are to be contracted directly by payers to manage the continuum of care the costs of market utilisation play an essential role. Transaction costs also arise in the course of the negotiation and implementation of contracts. These costs are the reason why it is generally not possible to conclude perfect (complete) contracts. Problems with asymmetric distribution of information can relate to the situation before a contract is concluded (adverse selection) and after conclusion of a contract (moral hazard). Discussion and Conclusions: Information asymmetries are seen as a major obstacle to the efficient operation of integrated care programmes. Coordination and motivation problems cannot be solved at no-costs. The presented problems in the design of selective individual contracts represent a necessary but not a sufficient condition for further government intervention. A state or political failures have to be assumed continuously. PMID:29588639
Contract Design: The problem of information asymmetry.
Mühlbacher, Axel C; Amelung, Volker E; Juhnke, Christin
2018-01-12
Integrated care systems are advocated as an effective method of improving the performance of healthcare systems. These systems outline a payment and care delivery model that intends to tie provider reimbursements to predefined quality metrics. Little is known about the contractual design and the main challenges of delegating "accountability" to these new kinds of organisations and/or contracts. The research question in this article focuses on how healthcare contracts can look like and which possible problems arise in designing such contracts. In this a special interest is placed on information asymmetries. A comprehensive literature review on methods of designing contracts in Integrated Care was conducted. This article is the first in a row of three that all contribute to a specific issue in designing healthcare contracts. Starting with the organisation of contracts and information asymmetries, part 2 focusses on financial options and risks and part 3 finally concludes with the question of risk management and evaluation. Healthcare contracting between providers and payers will have a major impact on the overall design of future healthcare systems. If Integrated care systems or any other similar concept of care delivery are to be contracted directly by payers to manage the continuum of care the costs of market utilisation play an essential role. Transaction costs also arise in the course of the negotiation and implementation of contracts. These costs are the reason why it is generally not possible to conclude perfect (complete) contracts. Problems with asymmetric distribution of information can relate to the situation before a contract is concluded (adverse selection) and after conclusion of a contract (moral hazard). Information asymmetries are seen as a major obstacle to the efficient operation of integrated care programmes. Coordination and motivation problems cannot be solved at no-costs. The presented problems in the design of selective individual contracts represent a necessary but not a sufficient condition for further government intervention. A state or political failures have to be assumed continuously.
Reflections on the relationship between artificial intelligence and operations research
NASA Technical Reports Server (NTRS)
Fox, Mark S.
1989-01-01
Historically, part of Artificial Intelligence's (AI's) roots lie in Operations Research (OR). How AI has extended the problem solving paradigm developed in OR is explored. In particular, by examining how scheduling problems are solved using OR and AI, it is demonstrated that AI extends OR's model of problem solving through the opportunistic use of knowledge, problem reformulation and learning.
NASA Astrophysics Data System (ADS)
Salgado, F.; Hudepohl, G.
2016-07-01
More than 10 years have already passed since the first Multiple Application Curvature Adaptive Optics (MACAO) facilities got the first light in UT2 the 18th of April, 2003, in the Very Large Telescope (VLT) at Paranal Observatory. The achievable image sharpness of a ground-based telescope is normally limited by the effect of atmospheric turbulence. However, with Adaptive Optics (AO) techniques, this major drawback can be overcome so that the telescope produces images that are as sharp as theoretically possible, i.e., as if they were taken from space. [1] The intention of this document is summarize in few pages some highlights related with the activities needed to keep MACAO units in operation. Some statistics of problems based in Action Remedy tool is included, showing how through these years the number of problems has been reduced, even when there are still some unsolved ones. Some lessons have been learned and there are others one to learn. Corrective and predictive maintenance performed are shown too like the current measurements, transfer functions measurements, thermography pictures, health checks measuring interaction matrix and flat vectors to detect dead APDs or short circuits in the DM, etc. Some forced interventions are included as well like the removal of the cabinets from Coude rooms to avoid that acoustic noise and vibrations perturb the operations, the deformable mirrors reached by cooling leaks and a mirror that got rusty are shown too. Well knowledge of the system, good interaction between different disciplines groups to perform corrective and preventive maintenance seems to be key aspects of keeping it under control and operative during all these years leading to this good result.
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.
Spent sealed radium sources conditioning in Latin America
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mourao, R.P.
1999-06-01
The management of spent sealed sources is considered by the International Atomic Energy Agency (IAEA) one of the greatest challenges faced by nuclear authorities today, especially in developing countries. One of the Agency`s initiatives to tackle this problem is the Spent Radium Sources Conditioning Project, a worldwide project relying on the regional co-operation between countries. A team from the Brazilian nuclear research institute Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) was chosen as the expert team to carry out the operations in Latin America; since December 1996 radium sources have been safely conditioned in Uruguay, Nicaragua, Guatemala, Ecuador and Paraguay.more » A Quality Assurance Program was established, encompassing the qualification of the capsule welding process, written operational procedures referring to all major steps of the operation, calibration of monitors and information retrievability. A 200L carbon steel drum-based packaging concept was used to condition the sources, its cavity being designed to receive the lead shield device containing stainless steel capsules with the radium sources. As a result of these operations, a total amount of 2,897 mg of needles, tubes, medical applicators, standard sources for calibration, lightning rods, secondary wastes and contaminated objects were stored in proper conditions and are now under control of the nuclear authorities of the visited countries.« less
Manual control aspects of orbital flight
NASA Technical Reports Server (NTRS)
Brody, Adam R.
1990-01-01
Studies of spacecraft rendezvous and docking operations began in the Gemini program in preparation for the two dockings required to send a crew to the moon and return them safely to Earth. However, the goal of getting to the moon before the end of the decade was of greater concern than mission optimization so little or no time or money was expended in researching human factors implications of operational aspects such as braking gates or control modes. Also, with sixteen operational dockings over a six year period (12 Apollo, 3 Skylab, and 1 ASTP) in the United States space program, economies of scale were not yet available to justify extensive research into decreasing the time or fuel necessary for a successful docking. With an operational space station era approaching in which orbital maneuvering vehicle (OMV), orbital transfer vehicle (OTV), shuttle orbiter, and other traffic will play a major role, a concerted research effort now could help avoid many potential problems later in addition to increasing safety, fuel economy, and productivity. A knowledge of manual control capabilities associated with piloted spaceflight could help save a life if the operational flight envelope can be safely enlarged to include faster dockings that currently envisioned. For example, current and future research is designed to acquire the appropriate information.
Non-operative advances: what has happened in the last 50 years in paediatric surgery?
Holland, Andrew J A; McBride, Craig A
2015-01-01
Paediatric surgeons remain paediatric clinicians who have the unique skill set to treat children with surgical problems that may require operative intervention. Many of the advances in paediatric surgical care have occurred outside the operating theatre and have involved significant input from medical, nursing and allied health colleagues. The establishment of neonatal intensive care units, especially those focusing on the care of surgical infants, has greatly enhanced the survival rates and long-term outcomes of those infants with major congenital anomalies requiring surgical repair. Educational initiatives such as the advanced trauma life support and emergency management of severe burns courses have facilitated improved understanding and clinical care. Paediatric surgeons have led with the non-operative management of solid organ injury following blunt abdominal trauma. Nano-crystalline burn wound dressings have enabled a reduced frequency of painful dressing changes in addition to effective antimicrobial efficacy and enhanced burn wound healing. Burns care has evolved so that many children may now be treated almost exclusively in an ambulatory care setting or as day case-only patients, with novel technologies allowing accurate prediction of burn would outcome and planning of elective operative intervention to achieve burn wound closure. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).
Solving TSP problem with improved genetic algorithm
NASA Astrophysics Data System (ADS)
Fu, Chunhua; Zhang, Lijun; Wang, Xiaojing; Qiao, Liying
2018-05-01
The TSP is a typical NP problem. The optimization of vehicle routing problem (VRP) and city pipeline optimization can use TSP to solve; therefore it is very important to the optimization for solving TSP problem. The genetic algorithm (GA) is one of ideal methods in solving it. The standard genetic algorithm has some limitations. Improving the selection operator of genetic algorithm, and importing elite retention strategy can ensure the select operation of quality, In mutation operation, using the adaptive algorithm selection can improve the quality of search results and variation, after the chromosome evolved one-way evolution reverse operation is added which can make the offspring inherit gene of parental quality improvement opportunities, and improve the ability of searching the optimal solution algorithm.
Lymphoedema of the lower limbs: management problems in a developing country.
Adigun, A I; Ogundipe, O K
2008-01-01
Lymphoedema is a clinical condition involving the extremities that is characterized by accumulation of protein rich fluid within the intercellular space of the skin and the subcutaneous tissue. It most frequently occurs in the extremities. Developing countries are mostly faced with cases of secondary lymphoedema where patients present lately. In addition to swollen limbs, there are lot of skin changes on the affected limb, these create a lot of problems to the managing clinician. We hereby present five cases out of several patients managed to highlight the challenges. We review the case notes of three patients managed by our unit and present the summary of each patient. Majority of our patients present late to the hospital, mainly because of the socio-cultural and spiritual beliefs concerning the aetiology of the condition. Most of them have visited the spiritualist, herbalist and the clergymen for solution. Clinicians in the developing countries are seriously handicapped by lack of modern equipment for both diagnostic and therapeutic management of these clinical conditions. Chronic lymphoedema is a major cause of permanent disability. Excisional surgery such as Charles procedure even though old is still very much relevant in our environment. Patients need to be enlightened on the need for early presentation, adequate post-operative care and prolonged follow-up.
Ghaniyoun, Aram; Shakeri, Khosro; Heidari, Mohammad
2017-09-01
Workers in social service professions are the first candidates for job burnout. The researchers believe this is due to daily exposure to stressful situations and lack of positive conditions in the workplace. It seems that psychological empowerment of staff can affect their job burnout. This study aimed to investigate the relationship between psychological empowerment and job burnout in operational staff of emergency center. This was a descriptive correlational study. A total of 1100 operational staff of emergency center were evaluated, and of which, 285 persons were selected by simple random sampling method. Data were collected using Spritzer's psychological empowerment and Maslach Burnout Inventory questionnaires. SPSS software, version 18, was used for data analysis along with descriptive analytical tests. The findings of this study revealed that the majority of units (46%) were in intermediate level in terms of empowerment. Similarly, the majority of cases had intermediate level (77.5%), and a minor percentage (8.4%) had low levels of job burnout. Based on Pearson's correlation test, there was a significant invert correlation between psychological empowerment and job burnout. This inverse and significant relationship was also observed between the four components of psychological empowerment (competence, self-determination, impact, and meaning) and job burnout. According to the results of the study, policy makers and health planners can take some measures in enhancing psychological empowerment to prevent problems associated with job burnout, by identifying stressors and strategies to deal with them.
Pooling knowledge and improving safety for contracted works at a large industrial park.
Agnello, Patrizia; Ansaldi, Silvia; Bragatto, Paolo
2015-01-01
At a large chemical park maintenance is contracted by the major companies operating the plants to many small firms. The cultural and psychological isolation of contractor workers was recognized a root cause of severe accidents in the recent years. That problem is common in chemical industry. The knowledge sharing has been assumed a good key to involve contractors and sub contractors in safety culture and contributing to injuries prevention. The selection of personal protective equipment PPE for the maintenance works has been taken as benchmark to demonstrate the adequateness of the proposed approach. To support plant operators, contractors and subcontractors in PPE discussion, a method has been developed. Its core is a knowledge-base, organized in an Ontology, as suitable for inferring decisions. By means of this tool all stakeholders have merged experience and information and find out the right PPE, to be provided, with adequate training and information package. PPE selection requires sound competencies about process and environmental hazards, including major accident, preventive and protective measures, maintenance activities. These pieces of knowledge previously fragmented among plant operators and contractors, have to be pooled, and used to find out the adequate PPE for a number of maintenance works. The PPE selection is per se important, but it is also a good chance to break the contractors' isolation and involve them in safety objectives. Thus by pooling experience and practical knowledge, the common understanding of safety issues has been strengthened.
Ghaniyoun, Aram; Shakeri, Khosro; Heidari, Mohammad
2017-01-01
Background: Workers in social service professions are the first candidates for job burnout. The researchers believe this is due to daily exposure to stressful situations and lack of positive conditions in the workplace. It seems that psychological empowerment of staff can affect their job burnout. This study aimed to investigate the relationship between psychological empowerment and job burnout in operational staff of emergency center. Methods: This was a descriptive correlational study. A total of 1100 operational staff of emergency center were evaluated, and of which, 285 persons were selected by simple random sampling method. Data were collected using Spritzer's psychological empowerment and Maslach Burnout Inventory questionnaires. SPSS software, version 18, was used for data analysis along with descriptive analytical tests. Results: The findings of this study revealed that the majority of units (46%) were in intermediate level in terms of empowerment. Similarly, the majority of cases had intermediate level (77.5%), and a minor percentage (8.4%) had low levels of job burnout. Based on Pearson's correlation test, there was a significant invert correlation between psychological empowerment and job burnout. This inverse and significant relationship was also observed between the four components of psychological empowerment (competence, self-determination, impact, and meaning) and job burnout. Conclusions: According to the results of the study, policy makers and health planners can take some measures in enhancing psychological empowerment to prevent problems associated with job burnout, by identifying stressors and strategies to deal with them. PMID:28970654
NASA Astrophysics Data System (ADS)
Penta, Raimondo; Gerisch, Alf
2017-01-01
The classical asymptotic homogenization approach for linear elastic composites with discontinuous material properties is considered as a starting point. The sharp length scale separation between the fine periodic structure and the whole material formally leads to anisotropic elastic-type balance equations on the coarse scale, where the arising fourth rank operator is to be computed solving single periodic cell problems on the fine scale. After revisiting the derivation of the problem, which here explicitly points out how the discontinuity in the individual constituents' elastic coefficients translates into stress jump interface conditions for the cell problems, we prove that the gradient of the cell problem solution is minor symmetric and that its cell average is zero. This property holds for perfect interfaces only (i.e., when the elastic displacement is continuous across the composite's interface) and can be used to assess the accuracy of the computed numerical solutions. These facts are further exploited, together with the individual constituents' elastic coefficients and the specific form of the cell problems, to prove a theorem that characterizes the fourth rank operator appearing in the coarse-scale elastic-type balance equations as a composite material effective elasticity tensor. We both recover known facts, such as minor and major symmetries and positive definiteness, and establish new facts concerning the Voigt and Reuss bounds. The latter are shown for the first time without assuming any equivalence between coarse and fine-scale energies ( Hill's condition), which, in contrast to the case of representative volume elements, does not identically hold in the context of asymptotic homogenization. We conclude with instructive three-dimensional numerical simulations of a soft elastic matrix with an embedded cubic stiffer inclusion to show the profile of the physically relevant elastic moduli (Young's and shear moduli) and Poisson's ratio at increasing (up to 100 %) inclusion's volume fraction, thus providing a proxy for the design of artificial elastic composites.
Czodrowski, Paul
2014-11-01
In the 1960s, the kappa statistic was introduced for the estimation of chance agreement in inter- and intra-rater reliability studies. The kappa statistic was strongly pushed by the medical field where it could be successfully applied via analyzing diagnoses of identical patient groups. Kappa is well suited for classification tasks where ranking is not considered. The main advantage of kappa is its simplicity and the general applicability to multi-class problems which is the major difference to receiver operating characteristic area under the curve. In this manuscript, I will outline the usage of kappa for classification tasks, and I will evaluate the role and uses of kappa in specifically machine learning and cheminformatics.
NASA Astrophysics Data System (ADS)
Romanovsky, Yurii M.; Tikhonov, Alexander N.
2010-12-01
The free energy released upon the enzymatic hydrolysis of adenosine triphosphate (ATP) is the main source of energy for the functioning of the living cell and all multicellular organisms. The overwhelming majority of ATP molecules are formed by proton ATP synthases, which are the smallest macromolecular electric motors in Nature. This paper reviews the modern concepts of the molecular structure and functioning of the proton ATP synthase, and real-time biophysical experiments on the rotation of the 'rotor' of this macromolecular motor. Some mathematical models describing the operation of this nanosized macromolecular machine are described.
Red rubber bulb, cheap and effective vacuum drainage.
Vatanasapt, V; Areemit, S; Jeeravipoolvarn, P; Kuyyakanond, T; Kuptarnond, C
1989-04-01
Red rubber bulbs have been used for vacuum drainage in head, neck, breast and several other operations by the authors since 1975 quite effectively without any major problems. The vacuum pressure of the red rubber bulbs was found to be higher than the expensive commercially available vacuum wound drainage device. The question of remaining old blood and infective microorganisms inside the reservoir for the reused ones were tested by the manual cleaning process and the standard sterile technique using steam under increased pressure (autoclave). The result is quite satisfactory. We encourage the use of this cheap and effective (made in Thailand) vacuum wound drainage in Thai hospitals and Thai medical schools.
Regenerable Photovoltaic Devices with a Hydrogel-Embedded Microvascular Network
Koo, Hyung-Jun; Velev, Orlin D.
2013-01-01
Light-driven degradation of photoactive molecules could be one of the major obstacles to stable long term operation of organic dye-based solar light harvesting devices. One solution to this problem may be mimicking the regeneration functionality of a plant leaf. We report an organic dye photovoltaic system that has been endowed with such microfluidic regeneration functionality. A hydrogel medium with embedded channels allows rapid and uniform supply of photoactive reagents by a convection-diffusion mechanism. A washing-activation cycle enables reliable replacement of the organic component in a dye-sensitized photovoltaic system. Repetitive restoration of photovoltaic performance after intensive device degradation is demonstrated. PMID:23912814
A 40 MWe floating OTEC plant at Punta Tuna, Puerto Rico
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dambly, B.W.
1981-01-01
A development project leading to a closed-cycle ocean thermal energy conversion (OTEC) pilot plant is considered. In connection with this project, a plan was submitted for design, construction, deployment, start-up, and operation of a 40 MWe floating electric generating plant at Punta Tuna, Puerto Rico. Attention is given to the OTEC concept, organizational aspects related to the project, the major problems regarding the OTEC program, and the commercialization plan. Questions of design philosophy are examined, taking into account the need for efficient heat exchangers, the minimization of water flow, the importance of achieving maximized efficiency, and requirements for environmental safety.
Public-private partnerships in China's urban water sector.
Zhong, Lijin; Mol, Arthur P J; Fu, Tao
2008-06-01
During the past decades, the traditional state monopoly in urban water management has been debated heavily, resulting in different forms and degrees of private sector involvement across the globe. Since the 1990s, China has also started experiments with new modes of urban water service management and governance in which the private sector is involved. It is premature to conclude whether the various forms of private sector involvement will successfully overcome the major problems (capital shortage, inefficient operation, and service quality) in China's water sector. But at the same time, private sector involvement in water provisioning and waste water treatments seems to have become mainstream in transitional China.
NASA Technical Reports Server (NTRS)
Aaron, John; Gabris, Edward A.; Sulzman, Frank M.; Connors, Mary M.; Pilcher, Carl
1989-01-01
NASA's Office of Aeronautics and Space Technology has undertaken a series of manned space presence-development efforts under the aegis of the Civil Space Technology Initiative (CSTI) and Project Pathfinder. Typical of these CSTI efforts is the Aeroassist Flight Experiment, which will demonstrate techniques suitable in aerobrake design for slow trajectories to Mars and for lunar mission return. Long-duration human operations in space are a major element of Pathfinder, giving attention to such problems as space radiation exposure effects that could be several orders of magnitude greater on interplanetary exploration missions than on typical Space Shuttle flights. Mars Observer and Lunar Observer orbital missions are planned as a steppingstone to manned planetary exploration.
SMART Application: One stop services bridging the gap between doctor and patients
NASA Astrophysics Data System (ADS)
Wiweko, Budi; Agung, P. G.; Narasati, Shabrina
2017-02-01
In this study, we describe the SMART IVF services that has been developed into android-based application as "SMART Application". In this application, we can find one stop services in IVF. This application is expected to help patients to plan effectively for IVF procedure, full access to their IVF information helps them ease off a lot of stress and anxiety in this very delicate and stressful phase in their lives and help the doctor to plan for the best intervention of patients who face infertility problems using Assisted Reproductive Technology (ART). SMART application will be compatible with all major mobile operating systems.
Modeling of composite beams and plates for static and dynamic analysis
NASA Technical Reports Server (NTRS)
Hodges, Dewey H.; Atilgan, Ali R.; Lee, Bok Woo
1990-01-01
A rigorous theory and corresponding computational algorithms was developed for a variety of problems regarding the analysis of composite beams and plates. The modeling approach is intended to be applicable to both static and dynamic analysis of generally anisotropic, nonhomogeneous beams and plates. Development of a theory for analysis of the local deformation of plates was the major focus. Some work was performed on global deformation of beams. Because of the strong parallel between beams and plates, the two were treated together as thin bodies, especially in cases where it will clarify the meaning of certain terminology and the motivation behind certain mathematical operations.
[Functional somatic syndromes from the view of cultural anthropology].
Nakagami, Ayako; Tsujiuchi, Takuya
2009-09-01
The functional somatic syndromes have acquired major socio-cultural and political dimensions. Socio-cultural factors clearly affect symptoms, suffering, and disability perception and reporting. And knowledge of explanatory models of bodily distress for patients from different cultural backgrounds is useful in the establishment of a stable doctor -patient relationship. FSS may be an operational category to bridge between medical explanatory model and patient's model. According to medical anthropology, sickness has two faces; illness and disease. "Disease" is the problem from the practitioner's perspective, and "illness" is the human experience of symptoms and suffering. In this paper, the anthropological research on chronic fatigue syndrome as "not real" illness experience was described.
Fast Flux Test Facility thermal and pressure transient events during Cycle 11
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ahrens, D. M.
1992-03-01
This report documents the thermal and pressure transients experienced by the Reactor Heat Transport System (RHTS) during Cycle 11 which included Cycles 11A, 11B-1, 11B-2 and 11C (i.e. 4 startups and 4 shutdowns). Cycle 11 consisted of a refueling period that began on March 14, 1989 and power operation which began on May 3, 1989 and ended on October 27, 1990. Transients resulted from secondary pump starts/stops while at refueling conditions. The major causes of transients at power were five unplanned reactor scrams from 100% power and problems with Loop 2 DHX Fan Controls During 11A.
Six pitfalls in firewall deployment
NASA Astrophysics Data System (ADS)
Wilner, Bruce
1996-03-01
This note describes six key pitfalls in the deployment of popular commercial firewalls. The term `deployment' is intended to include the architecture of the firewall software itself, the integration of the firewall with the operating system platform, and the interconnection of the complete hardware/software combination within its target environment. After reviewing the evolution of Internet firewalls against the backdrop of classical trusted systems development, specific flaws and oversights in the familiar commercial deployments are analyzed in some detail. While significantly costlier solutions are available that address some of these problems, the analysis is applicable to the overwhelming majority of firewalls in use at both commercial and Government installations.
Waste Management System overview for future spacecraft.
NASA Technical Reports Server (NTRS)
Ingelfinger, A. L.; Murray, R. W.
1973-01-01
Waste Management Systems (WMS) for post Apollo spacecraft will be significantly more sophisticated and earthlike in user procedures. Some of the features of the advanced WMS will be accommodation of both males and females, automatic operation, either tissue wipe or anal wash, measurement and sampling of urine, feces and vomitus for medical analysis, water recovery, and solids disposal. This paper presents an overview of the major problems of and approaches to waste management for future spacecraft. Some of the processes discussed are liquid/gas separation, the Dry-John, the Hydro-John, automated sampling, vapor compression distillation, vacuum distillation-catalytic oxidation, incineration, and the integration of the above into complete systems.
Genetic Algorithm for Traveling Salesman Problem with Modified Cycle Crossover Operator
Mohamd Shoukry, Alaa; Gani, Showkat
2017-01-01
Genetic algorithms are evolutionary techniques used for optimization purposes according to survival of the fittest idea. These methods do not ensure optimal solutions; however, they give good approximation usually in time. The genetic algorithms are useful for NP-hard problems, especially the traveling salesman problem. The genetic algorithm depends on selection criteria, crossover, and mutation operators. To tackle the traveling salesman problem using genetic algorithms, there are various representations such as binary, path, adjacency, ordinal, and matrix representations. In this article, we propose a new crossover operator for traveling salesman problem to minimize the total distance. This approach has been linked with path representation, which is the most natural way to represent a legal tour. Computational results are also reported with some traditional path representation methods like partially mapped and order crossovers along with new cycle crossover operator for some benchmark TSPLIB instances and found improvements. PMID:29209364
Genetic Algorithm for Traveling Salesman Problem with Modified Cycle Crossover Operator.
Hussain, Abid; Muhammad, Yousaf Shad; Nauman Sajid, M; Hussain, Ijaz; Mohamd Shoukry, Alaa; Gani, Showkat
2017-01-01
Genetic algorithms are evolutionary techniques used for optimization purposes according to survival of the fittest idea. These methods do not ensure optimal solutions; however, they give good approximation usually in time. The genetic algorithms are useful for NP-hard problems, especially the traveling salesman problem. The genetic algorithm depends on selection criteria, crossover, and mutation operators. To tackle the traveling salesman problem using genetic algorithms, there are various representations such as binary, path, adjacency, ordinal, and matrix representations. In this article, we propose a new crossover operator for traveling salesman problem to minimize the total distance. This approach has been linked with path representation, which is the most natural way to represent a legal tour. Computational results are also reported with some traditional path representation methods like partially mapped and order crossovers along with new cycle crossover operator for some benchmark TSPLIB instances and found improvements.
Back disorders and health problems among subway train operators exposed to whole-body vibration.
Johanning, E
1991-12-01
Back disease associated with whole-body vibration has not been evaluated for subway train operators. A recent study demonstrated that this group is exposed to whole-body vibration at levels above the international standard. To investigate this risk further, a self-administered questionnaire survey was conducted among subway train operators (N = 492) and a similar reference group (N = 92). The operators had a higher prevalence than the referents in all aspects of back problems, particularly for cervical and lower back pain. In a multiple logistic regression model, the odds ratio for sciatic pain among subway train operators was 3.9 (95% CI 1.7-8.6); the operators also had a higher risk of hearing-related problems (odds ratio 3.2, 95% CI 0.6-17.4) and of gastrointestinal problems (odds ratio 1.6, 95% CI 1.1-2.5). Although a cumulative dose-response relationship could not be statistically demonstrated, the findings appear to be related to exposure to whole-body vibration and inadequate ergonomic conditions.
Brandenburg, Marcus; Hahn, Gerd J
2018-06-01
Process industries typically involve complex manufacturing operations and thus require adequate decision support for aggregate production planning (APP). The need for powerful and efficient approaches to solve complex APP problems persists. Problem-specific solution approaches are advantageous compared to standardized approaches that are designed to provide basic decision support for a broad range of planning problems but inadequate to optimize under consideration of specific settings. This in turn calls for methods to compare different approaches regarding their computational performance and solution quality. In this paper, we present a benchmarking problem for APP in the chemical process industry. The presented problem focuses on (i) sustainable operations planning involving multiple alternative production modes/routings with specific production-related carbon emission and the social dimension of varying operating rates and (ii) integrated campaign planning with production mix/volume on the operational level. The mutual trade-offs between economic, environmental and social factors can be considered as externalized factors (production-related carbon emission and overtime working hours) as well as internalized ones (resulting costs). We provide data for all problem parameters in addition to a detailed verbal problem statement. We refer to Hahn and Brandenburg [1] for a first numerical analysis based on and for future research perspectives arising from this benchmarking problem.
Practical solutions for reducing container ships' waiting times at ports using simulation model
NASA Astrophysics Data System (ADS)
Sheikholeslami, Abdorreza; Ilati, Gholamreza; Yeganeh, Yones Eftekhari
2013-12-01
The main challenge for container ports is the planning required for berthing container ships while docked in port. Growth of containerization is creating problems for ports and container terminals as they reach their capacity limits of various resources which increasingly leads to traffic and port congestion. Good planning and management of container terminal operations reduces waiting time for liner ships. Reducing the waiting time improves the terminal's productivity and decreases the port difficulties. Two important keys to reducing waiting time with berth allocation are determining suitable access channel depths and increasing the number of berths which in this paper are studied and analyzed as practical solutions. Simulation based analysis is the only way to understand how various resources interact with each other and how they are affected in the berthing time of ships. We used the Enterprise Dynamics software to produce simulation models due to the complexity and nature of the problems. We further present case study for berth allocation simulation of the biggest container terminal in Iran and the optimum access channel depth and the number of berths are obtained from simulation results. The results show a significant reduction in the waiting time for container ships and can be useful for major functions in operations and development of container ship terminals.
Affinity adsorption of cells to surfaces and strategies for cell detachment.
Hubble, John
2007-01-01
The use of bio-specific interactions for the separation and recovery of bio-molecules is now widely established and in many cases the technique has successfully crossed the divide between bench and process scale operation. Although the major specificity advantage of affinity-based separations also applies to systems intended for cell fractionation, developments in this area have been slower. Many of the problems encountered result from attempts to take techniques developed for molecular systems and, with only minor modification to the conditions used, apply them for the separation of cells. This approach tends to ignore or at least trivialise the problems, which arise from the heterogeneous nature of a cell suspension and the multivalent nature of the cell/surface interaction. To develop viable separation processes on a larger scale, effective contacting strategies are required in separators that also allow detachment or recovery protocols that overcome the enhanced binding strength generated by multivalent interactions. The effects of interaction valency on interaction strength needs to be assessed and approaches developed to allow effective detachment and recovery of adsorbed cells without compromising cell viability. This article considers the influence of operating conditions on cell attachment and the extent to which multivalent interactions determine the strength of cell binding and subsequent detachment.
NASA Astrophysics Data System (ADS)
Rodrigo-Clavero, Maria-Elena; Rodrigo-Ilarri, Javier
2017-04-01
One of the most serious environmental problems in modern societies is the management and disposal of urban solid waste (MSW). Despite the efforts of the administration to promote recycling and reuse policies and energy recovery technologies, nowadays the majority of MSW still is disposed in sanitary landfills. During the phases of operation and post-closure maintenance of any solid waste disposal site, two of the most relevant problems are the production of leachate and the generation of biogas. The leachate and biogas production formation processes occur simultaneously over time and are coupled together through the consumption and/or production of water. However, no mathematical models have been easily identified that allow to the evaluation of the joint production of leachate and biogas, during the operational and the post-closure phase of an urban waste landfill. This paper introduces BIOLEACH, a new mathematical model programmed on a monthly scale, that evaluates the joint production of leachate and biogas applying water balance techniques and considers the management of the landfill as a bioreactor. The application of such a model on real landfills allows to perform an environmentally sustainable management that minimizes the environmental impacts produced being also economically more profitable.
Pancreatic transection from blunt trauma associated with vascular and biliary lesions: A case report
Baiocchi, Gian Luca; Tiberio, Guido AM; Gheza, Federico; Gardani, Marco; Cantù, Massimiliano; Portolani, Nazario; Giulini, Stefano Maria
2008-01-01
Major injuries of the pancreas may result in considerable morbidity and mortality when associated with vascular and visceral injuries. In such cases, a right diagnosis and a prompt surgical intervention are necessary to give a chance to the patient. We herein describe a case of blunt abdominal trauma in a 29-year-old man whose pancreatic rupture was associated with hepatic artery, splenic vein and extrahepatic bile duct damage. Immediate surgery was performed after computer tomography (CT), the haemorrhagic lesions dictate the emergency transfer to the operating room. Spleno-pancreatic resection was done with reconstruction of the hepatic artery, ligation of the splenic vein and a Roux-en-Y bilio-jejunal diversion. The early post-operative course was complicated by stenosis of the arterial reconstruction, which was treated by endovascular angioplasty followed by percutaneous drainage of symptomatic pseudocyst, rest and antibiotics. Finally, the patient was discharged and was alive without clinical problems at the time when we wrote this case report. The present case underlines the clinical relevance of vascular and visceral injuries associated with pancreatic trauma and the problems arising in the diagnostic evaluation and the surgical strategy of complex multiple visceral and vascular lesions in blunt abdominal trauma. PMID:18720548
Skipworth, R J E; Terrace, J D; Fulton, L A; Anderson, D N
2008-11-01
Imposed reductions in working hours will impact significantly on the ability of surgical trainees to achieve competency. The objective of this study was to obtain the opinions of Scottish surgical trainees concerning the training they receive, in order to inform and guide the development of future, high-standard training programmes. An anonymous questionnaire was sent to basic surgical trainees on the Edinburgh, Aberdeen and Dundee Basic Surgical Rotations commencing after August 2002. Thirty six questionnaire responses were analysed. Very few of the returned comments were complimentary to the existing training structure; indeed, most comments demonstrated significant trainee disappointment. Despite "regular" exposure to operative sessions, training tutorials and named consultant trainers, the most common concern was a perceived lack of high-quality, structured, operative exposure and responsibility. Textbooks and journals remain the most frequently utilised learning tools, with high-tech systems such as teleconferencing, videos, CD-ROMS, and DVDs being poorly exploited. Current surgical training is not meeting the expectation of the majority of its trainees. To solve this problem will require extensive revision of attitudes and current educational format. A greater emphasis on the integration of 21st century learning tools in the training programme may help bridge this gap.
Polio roundup. Grappling with the "problem" areas.
1998-03-01
As the war against poliomyelitis continues, eradication efforts must now succeed in some countries which have been subjected to natural disasters and in others which are enduring manmade disasters. Subnational immunization days (SNIDs) were most recently conducted in northern Somalia in two 5-day rounds last November and December amid widespread popular and political support. While villages in the arid, drought-plagued country are often inaccessible, flooding from heavy rains was the only real problem encountered by the vaccination campaign. More than 90% of the estimated 375,000 children under age 5 years in the target area were vaccinated and given vitamin A. Careful advance preparations contributed to the campaign's success. A 7-day campaign in mid-February got oral polio vaccine to more than 330,000 children in southern Sudan. Maintaining the vaccine cold chain was the major operational challenge in this setting. To that end, all available means were used, including placing vaccines into running streams to keep them cool. The program in Sudan was coordinated by the UN's Operation Lifeline Sudan. Heat, armed conflict, lack of infrastructure, the need to reach more than 80% of the population by air, infectious diseases, drought, and hungry packs of hyenas were some of the obstacles to overcome. A second round of vaccination is planned for southern Sudan in mid March.
NASA Astrophysics Data System (ADS)
Audibert, Lorenzo; Cakoni, Fioralba; Haddar, Houssem
2017-12-01
In this paper we develop a general mathematical framework to determine interior eigenvalues from a knowledge of the modified far field operator associated with an unknown (anisotropic) inhomogeneity. The modified far field operator is obtained by subtracting from the measured far field operator the computed far field operator corresponding to a well-posed scattering problem depending on one (possibly complex) parameter. Injectivity of this modified far field operator is related to an appropriate eigenvalue problem whose eigenvalues can be determined from the scattering data, and thus can be used to obtain information about material properties of the unknown inhomogeneity. We discuss here two examples of such modification leading to a Steklov eigenvalue problem, and a new type of the transmission eigenvalue problem. We present some numerical examples demonstrating the viability of our method for determining the interior eigenvalues form far field data.
NASA Astrophysics Data System (ADS)
Tang, Peipei; Wang, Chengjing; Dai, Xiaoxia
2016-04-01
In this paper, we propose a majorized Newton-CG augmented Lagrangian-based finite element method for 3D elastic frictionless contact problems. In this scheme, we discretize the restoration problem via the finite element method and reformulate it to a constrained optimization problem. Then we apply the majorized Newton-CG augmented Lagrangian method to solve the optimization problem, which is very suitable for the ill-conditioned case. Numerical results demonstrate that the proposed method is a very efficient algorithm for various large-scale 3D restorations of geological models, especially for the restoration of geological models with complicated faults.
Investigating the Conceptual Variation of Major Physics Textbooks
NASA Astrophysics Data System (ADS)
Stewart, John; Campbell, Richard; Clanton, Jessica
2008-04-01
The conceptual problem content of the electricity and magnetism chapters of seven major physics textbooks was investigated. The textbooks presented a total of 1600 conceptual electricity and magnetism problems. The solution to each problem was decomposed into its fundamental reasoning steps. These fundamental steps are, then, used to quantify the distribution of conceptual content among the set of topics common to the texts. The variation of the distribution of conceptual coverage within each text is studied. The variation between the major groupings of the textbooks (conceptual, algebra-based, and calculus-based) is also studied. A measure of the conceptual complexity of the problems in each text is presented.
ERIC Educational Resources Information Center
Olino, Thomas M.; Pettit, Jeremy W.; Klein, Daniel N.; Allen, Nicholas B.; Seeley, John R.; Lewinsohn, Peter M.
2008-01-01
The study examines the influence of parental and grandparental major depressive disorder (MDD) on behavior problems in children. The results conclude that MDD in parents and grandparents may result in high levels of incorporation problems of MDD in children but don't indicate additional risk.
ERIC Educational Resources Information Center
Ramnarain, Umesh
2014-01-01
A major impediment to problem solving in mathematics in the great majority of South African schools is that disadvantaged students from seriously impoverished learning environments are lacking in the necessary informal mathematical knowledge to develop their own strategies for solving non-routine problems. A randomized pretest-posttest control…
User Acceptability of Physiological and Other Measures of Hazardous States of Awareness
NASA Technical Reports Server (NTRS)
Dickinson, Terry L.; Milkulka, Peter J.; Kwan, Doris; Fitzgibbons, Amy A.; Jinadu, Florence R.; Freeman, Frederick G.; Scerbo, Mark W.; Pope, A. T. (Technical Monitor)
2001-01-01
Two studies explored user acceptance of devices that measure hazardous states of awareness. In the first study, critical incident data were collected in two workshops from 11 operators working as air traffic controllers or commercial pilots. These critical incident data were used to develop a survey of the acceptability of awareness measures. In the second study, the survey was administered to 100 people also working as air traffic controllers or commercial pilots. Results show that operators are open to the inclusion of technology to measure HSAs even if that technology is somewhat invasive as long as feedback about the HSAs is considered to be useful and helpful. Nonetheless, a major concern is the legal complications associated with being recorded, particularly for older and more experienced operators. Air traffic controllers emphasized the importance of sharing technology information with supervisors in order to receive backup or assistance under conditions of task overload, whereas pilots emphasized the influence of work schedules on problems with awareness. Recommendations are offered concerning the implementation of devices to measure hazardous states of awareness.
Evaluating thermoregulation in reptiles: the fallacy of the inappropriately applied method.
Seebacher, Frank; Shine, Richard
2004-01-01
Given the importance of heat in most biological processes, studies on thermoregulation have played a major role in understanding the ecology of ectothermic vertebrates. It is, however, difficult to assess whether body temperature is actually regulated, and several techniques have been developed that allow an objective assessment of thermoregulation. Almost all recent studies on reptiles follow a single methodology that, when used correctly, facilitates comparisons between species, climates, and so on. However, the use of operative temperatures in this methodology assumes zero heat capacity of the study animals and is, therefore, appropriate for small animals only. Operative temperatures represent potentially available body temperatures accurately for small animals but can substantially overestimate the ranges of body temperature available to larger animals whose slower rates of heating and cooling mean that they cannot reach equilibrium if they encounter operative temperatures that change rapidly through either space or time. This error may lead to serious misinterpretations of field data. We derive correction factors specific for body mass and rate of movement that can be used to estimate body temperature null distributions of larger reptiles, thereby overcoming this methodological problem.
Resilient Distribution System by Microgrids Formation After Natural Disasters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Chen; Wang, Jianhui; Qiu, Feng
2016-03-01
Microgrids with distributed generation provide a resilient solution in the case of major faults in a distribution system due to natural disasters. This paper proposes a novel distribution system operational approach by forming multiple microgrids energized by distributed generation from the radial distribution system in real-time operations, to restore critical loads from the power outage. Specifically, a mixed-integer linear program (MILP) is formulated to maximize the critical loads to be picked up while satisfying the self-adequacy and operation constraints for the microgrids formation problem, by controlling the ON/OFF status of the remotely controlled switch devices and distributed generation. A distributedmore » multi-agent coordination scheme is designed via local communications for the global information discovery as inputs of the optimization, which is suitable for autonomous communication requirements after the disastrous event. The formed microgrids can be further utilized for power quality control and can be connected to a larger microgrid before the restoration of the main grids is complete. Numerical results based on modified IEEE distribution test systems validate the effectiveness of our proposed scheme.« less
Root Cause Failure Analysis of Stator Winding Insulation failure on 6.2 MW hydropower generator
NASA Astrophysics Data System (ADS)
Adhi Nugroho, Agus; Widihastuti, Ida; Ary, As
2017-04-01
Insulation failure on generator winding insulation occurred in the Wonogiri Hydropower plant has caused stator damage since ase was short circuited to ground. The fault has made the generator stop to operate. Wonogiri Hydropower plant is one of the hydroelectric plants run by PT. Indonesia Power UBP Mrica with capacity 2 × 6.2 MW. To prevent damage to occur again on hydropower generators, an analysis is carried out using Root Cause Failure Analysis RCFA is a systematic approach to identify the root cause of the main orbasic root cause of a problem or a condition that is not wanted. There are several aspects to concerned such as: loading pattern and operations, protection systems, generator insulation resistance, vibration, the cleanliness of the air and the ambient air. Insulation damage caused by gradual inhomogeneous cooling at the surface of winding may lead in to partial discharge. In homogeneous cooling may present due to lattice hampered by dust and oil deposits. To avoid repetitive defects and unwanted condition above, it is necessary to perform major maintenance overhaul every 5000-6000 hours of operation.
Eivazi, Shahram; Afkari, Hoorieh; Bednarik, Roman; Leinonen, Ville; Tukiainen, Markku; Jääskeläinen, Juha E
2015-07-01
Developments in micro-neurosurgical microscopes have improved operating precision and ensured the quality of outcomes. Using the stereoscopic magnified view, however, necessitates frequent manual adjustments to the microscope during an operation. This article reports on an investigation of the interaction details concerning a state-of-the-art micro-neurosurgical microscope. The video data from detailed observations of neurosurgeons' interaction patterns with the microscope were analysed to examine disruptive events caused by adjusting the microscope. The primary findings show that interruptions caused by adjusting the microscope handgrips and mouth switch prolong the surgery time up to 10%. Surgeons, we observed, avoid interaction with the microscope's controls, settings, and configurations by working at the edge of the view, operating on a non-focused view, and assuming unergonomic body postures. The lack of an automatic method for adjusting the microscope is a major problem that causes interruptions during micro-neurosurgery. From this understanding of disruptive events, we discuss the opportunities and limitations of interactive technologies that aim to reduce the frequency or shorten the duration of interruptions caused by microscope adjustment.
NASA Technical Reports Server (NTRS)
Belcastro, Christine M.
2010-01-01
Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents and reducing them will require a holistic integrated intervention capability. Future onboard integrated system technologies developed for preventing loss of vehicle control accidents must be able to assure safe operation under the associated off-nominal conditions. The transition of these technologies into the commercial fleet will require their extensive validation and verification (V and V) and ultimate certification. The V and V of complex integrated systems poses major nontrivial technical challenges particularly for safety-critical operation under highly off-nominal conditions associated with aircraft loss-of-control events. This paper summarizes the V and V problem and presents a proposed process that could be applied to complex integrated safety-critical systems developed for preventing aircraft loss-of-control accidents. A summary of recent research accomplishments in this effort is also provided.
Installation-Restoration Program Preliminary Assessment, Naknek Recreational Camps, Alaska
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1989-04-01
The Hazardous Materials Technical Center (HMTC) was retained in January 1988 to conduct the Installation-Restoration Program (IRP) Preliminary Assessment of Naknek Recreational Camps, Alaska, DoD policy is to identify and fully evaluate suspected problems associated with past hazardous-material disposal sites on DoD facilities, control the migration of hazardous contamination from such facilities, and control hazards to health and welfare that may have resulted from these past operations. Past installation operations involved the use and disposal of materials and wastes that were subsequently categorized as hazardous. The major operations of Naknek Camp I and Camp II did not use or disposemore » of HM/HW; however, these camps were used by the Air Force as dump areas and landfills. Waste oils, fuels, and polychlorinated biphenyls (PCBs) were among the wastes disposed of during these dumping activities. Information obtained through interviews, records, and field observations resulted in the identification of three sites that are potentially contaminated with HM/HW. At each of the identified sites, the potential exists for contamination of surface water, soils, and/or ground water and subsequent contaminant migration.« less
Flight evaluation of a simple total energy-rate system with potential wind-shear application
NASA Technical Reports Server (NTRS)
Ostroff, A. J.; Hueschen, R. M.; Hellbaum, R. F.; Creedon, J. F.
1981-01-01
Wind shears can create havoc during aircraft terminal area operations and have been cited as the primary cause of several major aircraft accidents. A simple sensor, potentially having application to the wind-shear problem, was developed to rapidly measure aircraft total energy relative to the air mass. Combining this sensor with either a variometer or a rate-of-climb indicator provides a total energy-rate system which was successfully applied in soaring flight. The measured rate of change of aircraft energy can potentially be used on display/control systems of powered aircraft to reduce glide-slope deviations caused by wind shear. The experimental flight configuration and evaluations of the energy-rate system are described. Two mathematical models are developed: the first describes operation of the energy probe in a linear design region and the second model is for the nonlinear region. The calculated total rate is compared with measured signals for many different flight tests. Time history plots show the tow curves to be almost the same for the linear operating region and very close for the nonlinear region.
Preeti, Bajaj; Ashish, Ahuja; Shriram, Gosavi
2013-12-01
As the "Science of Medicine" is getting advanced day-by-day, need for better pedagogies & learning techniques are imperative. Problem Based Learning (PBL) is an effective way of delivering medical education in a coherent, integrated & focused manner. It has several advantages over conventional and age-old teaching methods of routine. It is based on principles of adult learning theory, including student's motivation, encouragement to set goals, think critically about decision making in day-to-day operations. Above all these, it stimulates challenge acceptance and learning curiosity among students and creates pragmatic educational program. To measure the effectiveness of the "Problem Based Learning" as compared to conventional theory/didactic lectures based learning. The study was conducted on 72 medical students from Dayanand Medical College & Hospital, Ludhiana. Two modules of problem based sessions designed and delivered. Pre & Post-test score's scientific statistical analysis was done. Student feed-back received based on questionnaire in the five-point Likert scale format. Significant improvement in overall performance observed. Feedback revealed majority agreement that "Problem-based learning" helped them create interest (88.8 %), better understanding (86%) & promotes self-directed subject learning (91.6 %). Substantial improvement in the post-test scores clearly reveals acceptance of PBL over conventional learning. PBL ensures better practical learning, ability to create interest, subject understanding. It is a modern-day educational strategy, an effective tool to objectively improve the knowledge acquisition in Medical Teaching.
NASA Technical Reports Server (NTRS)
Bowen, Brent D.; Headley, Dean E.; Kane, Karisa D.
1998-01-01
Enhancing competitiveness in the global airline industry is at the forefront of attention with airlines, government, and the flying public. The seemingly unchecked growth of major airline alliances is heralded as an enhancement to global competition. However, like many mega-conglomerates, mega-airlines will face complications driven by size regardless of the many recitations of enhanced efficiency. Outlined herein is a conceptual model to serve as a decision tool for policy-makers, managers, and consumers of airline services. This model is developed using public data for the United States (U.S.) major airline industry available from the U/S. Department of Transportation, Federal Aviation Administration, the National Aeronautics and Space Administration, the National Transportation Safety Board, and other public and private sector sources. Data points include number of accidents, pilot deviations, operational performance indicators, flight problems, and other factors. Data from these sources provide opportunity to develop a model based on a complex dot product equation of two vectors. A row vector is weighted for importance by a key informant panel of government, industry, and consumer experts, while a column vector is established with the factor value. The resulting equation, known as the national Airline Quality Rating (AQR), where Q is quality, C is weight, and V is the value of the variables, is stated Q=C[i1-19] x V[i1-19]. Looking at historical patterns of AQR results provides the basis for establishment of an industry benchmark for the purpose of enhancing airline operational performance. A 7 year average of overall operational performance provides the resulting benchmark indicator. Applications from this example can be applied to the many competitive environments of the global industry and assist policy-makers faced with rapidly changing regulatory challenges.
From Diagnosis to Action: An Automated Failure Advisor for Human Deep Space Missions
NASA Technical Reports Server (NTRS)
Colombano, Silvano; Spirkovska, Lilly; Baskaran, Vijayakumar; Morris, Paul; Mcdermott, William; Ossenfort, John; Bajwa, Anupa
2015-01-01
The major goal of current space system development at NASA is to enable human travel to deep space locations such as Mars and asteroids. At that distance, round trip communication with ground operators may take close to an hour, thus it becomes unfeasible to seek ground operator advice for problems that require immediate attention, either for crew safety or for activities that need to be performed at specific times for the attainment of scientific results. To achieve this goal, major reliance will need to be placed on automation systems capable of aiding the crew in detecting and diagnosing failures, assessing consequences of these failures, and providing guidance in repair activities that may be required. We report here on the most current step in the continuing development of such a system, and that is the addition of a Failure Response Advisor. In simple terms, we have a system in place the Advanced Caution and Warning System (ACAWS) to tell us what happened (failure diagnosis) and what happened because that happened (failure effects). The Failure Response Advisor will tell us what to do about it, how long until something must be done and why its important that something be done and will begin to approach the complex reasoning that is generally required for an optimal approach to automated system health management. This advice is based on the criticality and various timing elements, such as durations of activities and of component repairs, failure effects delay, and other factors. The failure advice is provided to operators (crew and mission controllers) together with the diagnostic and effects information. The operators also have the option to drill down for more information about the failure and the reasons for any suggested priorities.
Functional Analyses of the Problems in Non-English Majors' Writings
ERIC Educational Resources Information Center
Li, Shun-ying
2010-01-01
Problems in generating and organizing ideas, in coherence and language competence are common in non-English majors' writings, which decrease non-English majors' ability to use English as a tool to realize its pragmatic functions and meta-functions. The exam-centered objective, the product-oriented approach, the inefficient mode of instruction, the…
... Atypical depression may occur as a feature of major depression or of mild, long-lasting depression (dysthymia). Symptoms ... depression is a serious illness that can cause major problems. Atypical depression can result in emotional, behavioral and health problems ...
Income and children's behavioral functioning: a sequential mediation analysis.
Shelleby, Elizabeth C; Votruba-Drzal, Elizabeth; Shaw, Daniel S; Dishion, Thomas J; Wilson, Melvin N; Gardner, Frances
2014-12-01
Children from low-income households tend to exhibit higher levels of conduct problems and emotional problems, yet the pathways linking economic disadvantage to children's behavioral functioning are not well understood. This study uses data from the Early Steps Multisite (ESM) project (N = 731) to investigate associations between family income in early childhood and children's conduct problems and emotional problems in middle childhood. The study explores whether the associations from income to child conduct problems and emotional problems operate through maternal depressive symptoms and 3 family risk factors in early childhood-harsh parenting, parenting hassles, and chaos in the home environment. Results of a sequential mediation model revealed significant indirect effects of family income on children's conduct problems operating through maternal depressive symptoms and parenting hassles and indirect effects of family income on children's emotional problems operating through maternal depressive symptoms, chaos in the home environment, and parenting hassles. Implications of these findings for understanding processes through which income influences child functioning are discussed.
Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian
2015-10-23
The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m < n), such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP) complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation.
Sensitivity analysis and approximation methods for general eigenvalue problems
NASA Technical Reports Server (NTRS)
Murthy, D. V.; Haftka, R. T.
1986-01-01
Optimization of dynamic systems involving complex non-hermitian matrices is often computationally expensive. Major contributors to the computational expense are the sensitivity analysis and reanalysis of a modified design. The present work seeks to alleviate this computational burden by identifying efficient sensitivity analysis and approximate reanalysis methods. For the algebraic eigenvalue problem involving non-hermitian matrices, algorithms for sensitivity analysis and approximate reanalysis are classified, compared and evaluated for efficiency and accuracy. Proper eigenvector normalization is discussed. An improved method for calculating derivatives of eigenvectors is proposed based on a more rational normalization condition and taking advantage of matrix sparsity. Important numerical aspects of this method are also discussed. To alleviate the problem of reanalysis, various approximation methods for eigenvalues are proposed and evaluated. Linear and quadratic approximations are based directly on the Taylor series. Several approximation methods are developed based on the generalized Rayleigh quotient for the eigenvalue problem. Approximation methods based on trace theorem give high accuracy without needing any derivatives. Operation counts for the computation of the approximations are given. General recommendations are made for the selection of appropriate approximation technique as a function of the matrix size, number of design variables, number of eigenvalues of interest and the number of design points at which approximation is sought.