IS Success Model in E-Learning Context Based on Students' Perceptions
ERIC Educational Resources Information Center
Freeze, Ronald D.; Alshare, Khaled A.; Lane, Peggy L.; Wen, H. Joseph
2010-01-01
This study utilized the Information Systems Success (ISS) model in examining e-learning systems success. The study was built on the premise that system quality (SQ) and information quality (IQ) influence system use and user satisfaction, which in turn impact system success. A structural equation model (SEM), using LISREL, was used to test the…
Development of an Electronic Portfolio System Success Model: An Information Systems Approach
ERIC Educational Resources Information Center
Balaban, Igor; Mu, Enrique; Divjak, Blazenka
2013-01-01
This research has two main goals: to develop an instrument for assessing Electronic Portfolio (ePortfolio) success and to build a corresponding ePortfolio success model using DeLone and McLean's information systems success model as the theoretical framework. For this purpose, we developed an ePortfolio success measurement instrument and structural…
ERIC Educational Resources Information Center
Wang, Yi-Shun; Liao, Yi-Wen
2008-01-01
With the proliferation of the Internet and World Wide Web applications, people are increasingly interacting with government to citizen (G2C) eGovernment systems. It is therefore important to measure the success of G2C eGovernment systems from the citizen's perspective. While general information systems (IS) success models have received much…
Yu, Ping; Qian, Siyu
2018-01-01
Electronic health records (EHR) are introduced into healthcare organizations worldwide to improve patient safety, healthcare quality and efficiency. A rigorous evaluation of this technology is important to reduce potential negative effects on patient and staff, to provide decision makers with accurate information for system improvement and to ensure return on investment. Therefore, this study develops a theoretical model and questionnaire survey instrument to assess the success of organizational EHR in routine use from the viewpoint of nursing staff in residential aged care homes. The proposed research model incorporates six variables in the reformulated DeLone and McLean information systems success model: system quality, information quality, service quality, use, user satisfaction and net benefits. Two variables training and self-efficacy were also incorporated into the model. A questionnaire survey instrument was designed to measure the eight variables in the model. After a pilot test, the measurement scale was used to collect data from 243 nursing staff members in 10 residential aged care homes belonging to three management groups in Australia. Partial least squares path modeling was conducted to validate the model. The validated EHR systems success model predicts the impact of the four antecedent variables—training, self-efficacy, system quality and information quality—on the net benefits, the indicator of EHR systems success, through the intermittent variables use and user satisfaction. A 24-item measurement scale was developed to quantitatively evaluate the performance of an EHR system. The parsimonious EHR systems success model and the measurement scale can be used to benchmark EHR systems success across organizations and units and over time. PMID:29315323
Yu, Ping; Qian, Siyu
2018-01-01
Electronic health records (EHR) are introduced into healthcare organizations worldwide to improve patient safety, healthcare quality and efficiency. A rigorous evaluation of this technology is important to reduce potential negative effects on patient and staff, to provide decision makers with accurate information for system improvement and to ensure return on investment. Therefore, this study develops a theoretical model and questionnaire survey instrument to assess the success of organizational EHR in routine use from the viewpoint of nursing staff in residential aged care homes. The proposed research model incorporates six variables in the reformulated DeLone and McLean information systems success model: system quality, information quality, service quality, use, user satisfaction and net benefits. Two variables training and self-efficacy were also incorporated into the model. A questionnaire survey instrument was designed to measure the eight variables in the model. After a pilot test, the measurement scale was used to collect data from 243 nursing staff members in 10 residential aged care homes belonging to three management groups in Australia. Partial least squares path modeling was conducted to validate the model. The validated EHR systems success model predicts the impact of the four antecedent variables-training, self-efficacy, system quality and information quality-on the net benefits, the indicator of EHR systems success, through the intermittent variables use and user satisfaction. A 24-item measurement scale was developed to quantitatively evaluate the performance of an EHR system. The parsimonious EHR systems success model and the measurement scale can be used to benchmark EHR systems success across organizations and units and over time.
ERIC Educational Resources Information Center
Yakubu, M. Nasiru; Dasuki, Salihu Ibrahim
2018-01-01
Aim/Purpose: This study is based on the DeLone and McLean's Information Systems Success (D&M ISS) model, which was modified to determine the success factors responsible for the acceptance of an e-learning system called Canvas by students of a Nigerian University. Background: The adoption of eLearning has been under studied within the context…
Success Factors for e-Learning in a Developing Country: A Case Study of Serbia
ERIC Educational Resources Information Center
Raspopovic, Miroslava; Jankulovic, Aleksandar; Runic, Jovana; Lucic, Vanja
2014-01-01
In this paper, DeLone and McLean's updated information system model was used to evaluate the success of an e-Learning system and its courses in a transitional country like Serbia. In order to adapt this model to an e-Learning system, suitable success metrics were chosen for each of the evaluation stages. Furthermore, the success metrics for…
Choi, Wona; Rho, Mi Jung; Park, Jiyun; Kim, Kwang-Jum; Kwon, Young Dae; Choi, In Young
2013-06-01
Intensified competitiveness in the healthcare industry has increased the number of healthcare centers and propelled the introduction of customer relationship management (CRM) systems to meet diverse customer demands. This study aimed to develop the information system success model of the CRM system by investigating previously proposed indicators within the model. THE EVALUATION AREAS OF THE CRM SYSTEM INCLUDES THREE AREAS: the system characteristics area (system quality, information quality, and service quality), the user area (perceived usefulness and user satisfaction), and the performance area (personal performance and organizational performance). Detailed evaluation criteria of the three areas were developed, and its validity was verified by a survey administered to CRM system users in 13 nationwide health promotion centers. The survey data were analyzed by the structural equation modeling method, and the results confirmed that the model is feasible. Information quality and service quality showed a statistically significant relationship with perceived usefulness and user satisfaction. Consequently, the perceived usefulness and user satisfaction had significant influence on individual performance as well as an indirect influence on organizational performance. This study extends the research area on information success from general information systems to CRM systems in health promotion centers applying a previous information success model. This lays a foundation for evaluating health promotion center systems and provides a useful guide for successful implementation of hospital CRM systems.
Choi, Wona; Rho, Mi Jung; Park, Jiyun; Kim, Kwang-Jum; Kwon, Young Dae
2013-01-01
Objectives Intensified competitiveness in the healthcare industry has increased the number of healthcare centers and propelled the introduction of customer relationship management (CRM) systems to meet diverse customer demands. This study aimed to develop the information system success model of the CRM system by investigating previously proposed indicators within the model. Methods The evaluation areas of the CRM system includes three areas: the system characteristics area (system quality, information quality, and service quality), the user area (perceived usefulness and user satisfaction), and the performance area (personal performance and organizational performance). Detailed evaluation criteria of the three areas were developed, and its validity was verified by a survey administered to CRM system users in 13 nationwide health promotion centers. The survey data were analyzed by the structural equation modeling method, and the results confirmed that the model is feasible. Results Information quality and service quality showed a statistically significant relationship with perceived usefulness and user satisfaction. Consequently, the perceived usefulness and user satisfaction had significant influence on individual performance as well as an indirect influence on organizational performance. Conclusions This study extends the research area on information success from general information systems to CRM systems in health promotion centers applying a previous information success model. This lays a foundation for evaluating health promotion center systems and provides a useful guide for successful implementation of hospital CRM systems. PMID:23882416
Knowledge management systems success in healthcare: Leadership matters.
Ali, Nor'ashikin; Tretiakov, Alexei; Whiddett, Dick; Hunter, Inga
2017-01-01
To deliver high-quality healthcare doctors need to access, interpret, and share appropriate and localised medical knowledge. Information technology is widely used to facilitate the management of this knowledge in healthcare organisations. The purpose of this study is to develop a knowledge management systems success model for healthcare organisations. A model was formulated by extending an existing generic knowledge management systems success model by including organisational and system factors relevant to healthcare. It was tested by using data obtained from 263 doctors working within two district health boards in New Zealand. Of the system factors, knowledge content quality was found to be particularly important for knowledge management systems success. Of the organisational factors, leadership was the most important, and more important than incentives. Leadership promoted knowledge management systems success primarily by positively affecting knowledge content quality. Leadership also promoted knowledge management use for retrieval, which should lead to the use of that better quality knowledge by the doctors, ultimately resulting in better outcomes for patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Human Factors Interface with Systems Engineering for NASA Human Spaceflights
NASA Technical Reports Server (NTRS)
Wong, Douglas T.
2009-01-01
This paper summarizes the past and present successes of the Habitability and Human Factors Branch (HHFB) at NASA Johnson Space Center s Space Life Sciences Directorate (SLSD) in including the Human-As-A-System (HAAS) model in many NASA programs and what steps to be taken to integrate the Human-Centered Design Philosophy (HCDP) into NASA s Systems Engineering (SE) process. The HAAS model stresses systems are ultimately designed for the humans; the humans should therefore be considered as a system within the systems. Therefore, the model places strong emphasis on human factors engineering. Since 1987, the HHFB has been engaging with many major NASA programs with much success. The HHFB helped create the NASA Standard 3000 (a human factors engineering practice guide) and the Human Systems Integration Requirements document. These efforts resulted in the HAAS model being included in many NASA programs. As an example, the HAAS model has been successfully introduced into the programmatic and systems engineering structures of the International Space Station Program (ISSP). Success in the ISSP caused other NASA programs to recognize the importance of the HAAS concept. Also due to this success, the HHFB helped update NASA s Systems Engineering Handbook in December 2007 to include HAAS as a recommended practice. Nonetheless, the HAAS model has yet to become an integral part of the NASA SE process. Besides continuing in integrating HAAS into current and future NASA programs, the HHFB will investigate incorporating the Human-Centered Design Philosophy (HCDP) into the NASA SE Handbook. The HCDP goes further than the HAAS model by emphasizing a holistic and iterative human-centered systems design concept.
An Analytic Model for the Success Rate of a Robotic Actuator System in Hitting Random Targets.
Bradley, Stuart
2015-11-20
Autonomous robotic systems are increasingly being used in a wide range of applications such as precision agriculture, medicine, and the military. These systems have common features which often includes an action by an "actuator" interacting with a target. While simulations and measurements exist for the success rate of hitting targets by some systems, there is a dearth of analytic models which can give insight into, and guidance on optimization, of new robotic systems. The present paper develops a simple model for estimation of the success rate for hitting random targets from a moving platform. The model has two main dimensionless parameters: the ratio of actuator spacing to target diameter; and the ratio of platform distance moved (between actuator "firings") to the target diameter. It is found that regions of parameter space having specified high success are described by simple equations, providing guidance on design. The role of a "cost function" is introduced which, when minimized, provides optimization of design, operating, and risk mitigation costs.
Establishing a Cloud Computing Success Model for Hospitals in Taiwan.
Lian, Jiunn-Woei
2017-01-01
The purpose of this study is to understand the critical quality-related factors that affect cloud computing success of hospitals in Taiwan. In this study, private cloud computing is the major research target. The chief information officers participated in a questionnaire survey. The results indicate that the integration of trust into the information systems success model will have acceptable explanatory power to understand cloud computing success in the hospital. Moreover, information quality and system quality directly affect cloud computing satisfaction, whereas service quality indirectly affects the satisfaction through trust. In other words, trust serves as the mediator between service quality and satisfaction. This cloud computing success model will help hospitals evaluate or achieve success after adopting private cloud computing health care services.
Establishing a Cloud Computing Success Model for Hospitals in Taiwan
Lian, Jiunn-Woei
2017-01-01
The purpose of this study is to understand the critical quality-related factors that affect cloud computing success of hospitals in Taiwan. In this study, private cloud computing is the major research target. The chief information officers participated in a questionnaire survey. The results indicate that the integration of trust into the information systems success model will have acceptable explanatory power to understand cloud computing success in the hospital. Moreover, information quality and system quality directly affect cloud computing satisfaction, whereas service quality indirectly affects the satisfaction through trust. In other words, trust serves as the mediator between service quality and satisfaction. This cloud computing success model will help hospitals evaluate or achieve success after adopting private cloud computing health care services. PMID:28112020
Development and initial evaluation of the Clinical Information Systems Success Model (CISSM).
Garcia-Smith, Dianna; Effken, Judith A
2013-06-01
Most clinical information systems (CIS) today are technically sound, but the number of successful implementations of these systems is low. The purpose of this study was to develop and test a theoretically based integrated CIS Success Model (CISSM) from the nurse perspective. Model predictors of CIS success were taken from existing research on information systems acceptance, user satisfaction, use intention, user behavior and perceptions, as well as clinical research. Data collected online from 234 registered nurses in four hospitals were used to test the model. Each nurse had used the Cerner Power Chart Admission Health Profile for at least 3 months. Psychometric testing and factor analysis of the 23-item CISSM instrument established its construct validity and reliability. Initial analysis showed nurses' satisfaction with and dependency on CIS use predicted their perceived CIS use Net Benefit. Further analysis identified Social Influence and Facilitating Conditions as other predictors of CIS user Net Benefit. The level of hospital CIS integration may account for the role of CIS Use Dependency in the success of CIS. Based on our experience, CISSM provides a formative as well as summative tool for evaluating CIS success from the nurse's perspective. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
The Role of Involvement in Learning Management System Success
ERIC Educational Resources Information Center
Klobas, Jane E.; McGill, Tanya J.
2010-01-01
Learning management systems (LMS) have been adopted by the majority of higher education institutions and research that explores the factors that influence the success of LMS is needed. This paper investigates the roles of student and instructor involvement in LMS success, using the DeLone and McLean (2003) model of information systems success as a…
ERIC Educational Resources Information Center
Yang, Ming; Shao, Zhen; Liu, Qian; Liu, Chuiyi
2017-01-01
The massive open online course (MOOC) is emerging as the new paradigm for modern education. The success of MOOCs depends on learners' continued usage. Drawing upon the information systems success model (IS success model) and technology acceptance model, a theoretical model for studying learners' continuance intentions toward participation in MOOCs…
Defining, Assessing, and Promoting E-Learning Success: An Information Systems Perspective
ERIC Educational Resources Information Center
Holsapple, Clyde W.; Lee-Post, Anita
2006-01-01
This research advances the understanding of how to define, evaluate, and promote e-learning success from an information systems perspective. It introduces the E-Learning Success Model, which posits that the overall success of an e-learning initiative depends on the attainment of success at each of the three stages of e-learning systems…
Exploring nursing e-learning systems success based on information system success model.
Chang, Hui-Chuan; Liu, Chung-Feng; Hwang, Hsin-Ginn
2011-12-01
E-learning is thought of as an innovative approach to enhance nurses' care service knowledge. Extensive research has provided rich information toward system development, courses design, and nurses' satisfaction with an e-learning system. However, a comprehensive view in understanding nursing e-learning system success is an important but less focused-on topic. The purpose of this research was to explore net benefits of nursing e-learning systems based on the updated DeLone and McLean's Information System Success Model. The study used a self-administered questionnaire to collected 208 valid nurses' responses from 21 of Taiwan's medium- and large-scale hospitals that have implemented nursing e-learning systems. The result confirms that the model is sufficient to explore the nurses' use of e-learning systems in terms of intention to use, user satisfaction, and net benefits. However, while the three exogenous quality factors (system quality, information quality, and service quality) were all found to be critical factors affecting user satisfaction, only information quality showed a direct effect on the intention to use. This study provides useful insights for evaluating nursing e-learning system qualities as well as an understanding of nurses' intentions and satisfaction related to performance benefits.
ERIC Educational Resources Information Center
Arenas-Gaitán, Jorge; Rondán-Cataluña, Francisco Javier; Ramírez-Correa, Patricio E.
2018-01-01
There is not a unique attitude towards the implementation of digital technology in educational sceneries. This paper aims to validate an adaptation of the DeLone and McLean information systems success model in the context of a learning management system. Furthermore, this study means to prove (1) the necessity of segmenting students in order to…
NASA Astrophysics Data System (ADS)
ChePa, Noraziah; Jasin, Noorhayati Md; Bakar, Nur Azzah Abu
2017-10-01
Fail to prevent or control challenges of Information System (IS) implementation have led to the failure of its implementation. Successful implementation of IS has been a challenging task to any organization including government hospitals. Government has invested a big amount of money on information system (IS) projects to improve service delivery in healthcare. However, several of them failed to be implemented successfully due to several factors. This article proposes a prevention model which incorporated Change Management (CM) concepts to avoid the failure of IS implementation, hence ensuring the success of it. Challenges of IS implementation in government hospitals have been discovered. Extensive literature review and deep interview approaches were employed to discover these challenges. A prevention model has been designed to cater the challenges. The model caters three main phases of implementation; pre-implementation, during implementation, and post-implementation by adopting CM practices of Lewin's, Kotter's and Prosci's CM model. Six elements of CM comprising thirteen sub-elements adopted from the three CM models have been used to handle CFFs of Human and Support issues; guiding team, resistance avoidance, IS adoption, enforcement, monitoring, and IS sustainability. Successful practice of the proposed mapping is expected to prevent CFFs to occur, hence ensuring a successful implementation of IS in the hospitals. The proposed model has been presented and successfully evaluated by the domain experts from the selected hospitals. The proposed model is believed to be beneficial for top management, IT practitioners and medical practitioners in preventing IS implementation failure among government hospitals towards ensuring the success implementation.
Validation of the DeLone and McLean Information Systems Success Model.
Ojo, Adebowale I
2017-01-01
This study is an adaptation of the widely used DeLone and McLean information system success model in the context of hospital information systems in a developing country. A survey research design was adopted in the study. A structured questionnaire was used to collect data from 442 health information management personnel in five Nigerian teaching hospitals. A structural equation modeling technique was used to validate the model's constructs. It was revealed that system quality significantly influenced use (β = 0.53, p < 0.001) and user satisfaction (β = 0.17, p < 0.001). Information quality significantly influenced use (β = 0.24, p < 0.001) and user satisfaction (β = 0.17, p < 0.001). Also, service quality significantly influenced use (β = 0.22, p < 0.001) and user satisfaction (β = 0.51, p < 0.001). However, use did not significantly influence user satisfaction (β = 0.00, p > 0.05), but it significantly influenced perceived net benefits (β = 0.21, p < 0.001). Furthermore, user satisfaction did not significantly influence perceived net benefits (β = 0.00, p > 0.05). The study validates the DeLone and McLean information system success model in the context of a hospital information system in a developing country. Importantly, system quality and use were found to be important measures of hospital information system success. It is, therefore, imperative that hospital information systems are designed in such ways that are easy to use, flexible, and functional to serve their purpose.
Validation of the DeLone and McLean Information Systems Success Model
2017-01-01
Objectives This study is an adaptation of the widely used DeLone and McLean information system success model in the context of hospital information systems in a developing country. Methods A survey research design was adopted in the study. A structured questionnaire was used to collect data from 442 health information management personnel in five Nigerian teaching hospitals. A structural equation modeling technique was used to validate the model's constructs. Results It was revealed that system quality significantly influenced use (β = 0.53, p < 0.001) and user satisfaction (β = 0.17, p < 0.001). Information quality significantly influenced use (β = 0.24, p < 0.001) and user satisfaction (β = 0.17, p < 0.001). Also, service quality significantly influenced use (β = 0.22, p < 0.001) and user satisfaction (β = 0.51, p < 0.001). However, use did not significantly influence user satisfaction (β = 0.00, p > 0.05), but it significantly influenced perceived net benefits (β = 0.21, p < 0.001). Furthermore, user satisfaction did not significantly influence perceived net benefits (β = 0.00, p > 0.05). Conclusions The study validates the DeLone and McLean information system success model in the context of a hospital information system in a developing country. Importantly, system quality and use were found to be important measures of hospital information system success. It is, therefore, imperative that hospital information systems are designed in such ways that are easy to use, flexible, and functional to serve their purpose. PMID:28261532
Educational Attainment: Success to the Successful
ERIC Educational Resources Information Center
Anthony, Peter; Gould, David; Smith, Gina
2013-01-01
Systems archetypes are patterns of structure found in systems that are helpful in understanding some of the dynamics within them. The intent of this study was to examine educational attainment data using the success-to-the-successful archetype as a model to see if it helps to explain the inequality observed in the data. Data covering 1990 to 2009…
A Markov chain model for reliability growth and decay
NASA Technical Reports Server (NTRS)
Siegrist, K.
1982-01-01
A mathematical model is developed to describe a complex system undergoing a sequence of trials in which there is interaction between the internal states of the system and the outcomes of the trials. For example, the model might describe a system undergoing testing that is redesigned after each failure. The basic assumptions for the model are that the state of the system after a trial depends probabilistically only on the state before the trial and on the outcome of the trial and that the outcome of a trial depends probabilistically only on the state of the system before the trial. It is shown that under these basic assumptions, the successive states form a Markov chain and the successive states and outcomes jointly form a Markov chain. General results are obtained for the transition probabilities, steady-state distributions, etc. A special case studied in detail describes a system that has two possible state ('repaired' and 'unrepaired') undergoing trials that have three possible outcomes ('inherent failure', 'assignable-cause' 'failure' and 'success'). For this model, the reliability function is computed explicitly and an optimal repair policy is obtained.
NASA Technical Reports Server (NTRS)
Breckenridge, Jonathan T.; Johnson, Stephen B.
2013-01-01
This paper describes the core framework used to implement a Goal-Function Tree (GFT) based systems engineering process using the Systems Modeling Language. It defines a set of principles built upon by the theoretical approach described in the InfoTech 2013 ISHM paper titled "Goal-Function Tree Modeling for Systems Engineering and Fault Management" presented by Dr. Stephen B. Johnson. Using the SysML language, the principles in this paper describe the expansion of the SysML language as a baseline in order to: hierarchically describe a system, describe that system functionally within success space, and allocate detection mechanisms to success functions for system protection.
Reliability model of a monopropellant auxiliary propulsion system
NASA Technical Reports Server (NTRS)
Greenberg, J. S.
1971-01-01
A mathematical model and associated computer code has been developed which computes the reliability of a monopropellant blowdown hydrazine spacecraft auxiliary propulsion system as a function of time. The propulsion system is used to adjust or modify the spacecraft orbit over an extended period of time. The multiple orbit corrections are the multiple objectives which the auxiliary propulsion system is designed to achieve. Thus the reliability model computes the probability of successfully accomplishing each of the desired orbit corrections. To accomplish this, the reliability model interfaces with a computer code that models the performance of a blowdown (unregulated) monopropellant auxiliary propulsion system. The computer code acts as a performance model and as such gives an accurate time history of the system operating parameters. The basic timing and status information is passed on to and utilized by the reliability model which establishes the probability of successfully accomplishing the orbit corrections.
Visual recognition system of cherry picking robot based on Lab color model
NASA Astrophysics Data System (ADS)
Zhang, Qirong; Zuo, Jianjun; Yu, Tingzhong; Wang, Yan
2017-12-01
This paper designs a visual recognition system suitable for cherry picking. First, the system deals with the image using the vector median filter. And then it extracts a channel of Lab color model to divide the cherries and the background. The cherry contour was successfully fitted by the least square method, and the centroid and radius of the cherry were extracted. Finally, the cherry was successfully extracted.
Health information systems: failure, success and improvisation.
Heeks, Richard
2006-02-01
The generalised assumption of health information systems (HIS) success is questioned by a few commentators in the medical informatics field. They point to widespread HIS failure. The purpose of this paper was therefore to develop a better conceptual foundation for, and practical guidance on, health information systems failure (and success). Literature and case analysis plus pilot testing of developed model. Defining HIS failure and success is complex, and the current evidence base on HIS success and failure rates was found to be weak. Nonetheless, the best current estimate is that HIS failure is an important problem. The paper therefore derives and explains the "design-reality gap" conceptual model. This is shown to be robust in explaining multiple cases of HIS success and failure, yet provides a contingency that encompasses the differences which exist in different HIS contexts. The design-reality gap model is piloted to demonstrate its value as a tool for risk assessment and mitigation on HIS projects. It also throws into question traditional, structured development methodologies, highlighting the importance of emergent change and improvisation in HIS. The design-reality gap model can be used to address the problem of HIS failure, both as a post hoc evaluative tool and as a pre hoc risk assessment and mitigation tool. It also validates a set of methods, techniques, roles and competencies needed to support the dynamic improvisations that are found to underpin cases of HIS success.
ERIC Educational Resources Information Center
Lwoga, Edda Tandi
2013-01-01
Purpose: This study aims to examine the suitability of information systems (IS) success model in the adoption of library 2.0 technologies among undergraduate students in the African context, and focused at the Muhimbili University of Health and Allied Sciences (MUHAS) of Tanzania. Design/methodology/approach: Based on the IS success model, the…
ERIC Educational Resources Information Center
Kim, Kihyun; Trimi, Silvana; Park, Hyesung; Rhee, Shanggeun
2012-01-01
Course Management Systems (CMSs) in higher education have emerged as one of the most widely adopted e-learning platforms. This study examines the success of e-learning CMSs based on user satisfaction and benefits. Using DeLone and McLean's information system success model as a theoretical framework, we analyze the success of e-learning CMSs in…
Early Formulation Model-centric Engineering on Nasa's Europa Mission Concept Study
NASA Technical Reports Server (NTRS)
Bayer, Todd; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert;
2012-01-01
By leveraging the existing Model-Based Systems Engineering (MBSE) infrastructure at JPL and adding a modest investment, the Europa Mission Concept Study made striking advances in mission concept capture and analysis. This effort has reaffirmed the importance of architecting and successfully harnessed the synergistic relationship of system modeling to mission architecting. It clearly demonstrated that MBSE can provide greater agility than traditional systems engineering methods. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.
Safety Verification of a Fault Tolerant Reconfigurable Autonomous Goal-Based Robotic Control System
NASA Technical Reports Server (NTRS)
Braman, Julia M. B.; Murray, Richard M; Wagner, David A.
2007-01-01
Fault tolerance and safety verification of control systems are essential for the success of autonomous robotic systems. A control architecture called Mission Data System (MDS), developed at the Jet Propulsion Laboratory, takes a goal-based control approach. In this paper, a method for converting goal network control programs into linear hybrid systems is developed. The linear hybrid system can then be verified for safety in the presence of failures using existing symbolic model checkers. An example task is simulated in MDS and successfully verified using HyTech, a symbolic model checking software for linear hybrid systems.
Spatial distribution and male mating success of Anopheles gambiae swarms
2011-01-01
Background Anopheles gambiae mates in flight at particular mating sites over specific landmarks known as swarm markers. The swarms are composed of males; females typically approach a swarm, and leave in copula. This mating aggregation looks like a lek, but appears to lack the component of female choice. To investigate the possible mechanisms promoting the evolution of swarming in this mosquito species, we looked at the variation in mating success between swarms and discussed the factors that structure it in light of the three major lekking models, known as the female preference model, the hotspot model, and the hotshot model. Results We found substantial variation in swarm size and in mating success between swarms. A strong correlation between swarm size and mating success was observed, and consistent with the hotspot model of lek formation, the per capita mating success of individual males did not increase with swarm size. For the spatial distribution of swarms, our results revealed that some display sites were more attractive to both males and females and that females were more attracted to large swarms. While the swarm markers we recognize help us in localizing swarms, they did not account for the variation in swarm size or in the swarm mating success, suggesting that mosquitoes probably are attracted to these markers, but also perceive and respond to other aspects of the swarming site. Conclusions Characterizing the mating system of a species helps understand how this species has evolved and how selective pressures operate on male and female traits. The current study looked at male mating success of An. gambiae and discussed possible factors that account for its variation. We found that swarms of An. gambiae conform to the hotspot model of lek formation. But because swarms may lack the female choice component, we propose that the An. gambiae mating system is a lek-like system that incorporates characteristics pertaining to other mating systems such as scramble mating competition. PMID:21711542
Cho, Kyoung Won; Bae, Sung-Kwon; Ryu, Ji-Hye; Kim, Kyeong Na; An, Chang-Ho; Chae, Young Moon
2015-01-01
This study was to evaluate the performance of the newly developed information system (IS) implemented on July 1, 2014 at three public hospitals in Korea. User satisfaction scores of twelve key performance indicators of six IS success factors based on the DeLone and McLean IS Success Model were utilized to evaluate IS performance before and after the newly developed system was introduced. All scores increased after system introduction except for the completeness of medical records and impact on the clinical environment. The relationships among six IS factors were also analyzed to identify the important factors influencing three IS success factors (Intention to Use, User Satisfaction, and Net Benefits). All relationships were significant except for the relationships among Service Quality, Intention to Use, and Net Benefits. The results suggest that hospitals should not only focus on systems and information quality; rather, they should also continuously improve service quality to improve user satisfaction and eventually reach full the potential of IS performance.
Male dominance rank and reproductive success in chimpanzees, Pan troglodytes schweinfurthii.
Wroblewski, Emily E; Murray, Carson M; Keele, Brandon F; Schumacher-Stankey, Joann C; Hahn, Beatrice H; Pusey, Anne E
2009-01-01
Competition for fertile females determines male reproductive success in many species. The priority of access model predicts that male dominance rank determines access to females, but this model has been difficult to test in wild populations, particularly in promiscuous mating systems. Tests of the model have produced variable results, probably because of the differing socioecological circumstances of individual species and populations. We tested the predictions of the priority of access model in the chimpanzees of Gombe National Park, Tanzania. Chimpanzees are an interesting species in which to test the model because of their fission-fusion grouping patterns, promiscuous mating system and alternative male mating strategies. We determined paternity for 34 offspring over a 22-year period and found that the priority of access model was generally predictive of male reproductive success. However, we found that younger males had higher success per male than older males, and low-ranking males sired more offspring than predicted. Low-ranking males sired offspring with younger, less desirable females and by engaging in consortships more often than high-ranking fathers. Although alpha males never sired offspring with related females, inbreeding avoidance of high-ranking male relatives did not completely explain the success of low-ranking males. While our work confirms that male rank typically predicts male chimpanzee reproductive success, other factors are also important; mate choice and alternative male strategies can give low-ranking males access to females more often than would be predicted by the model. Furthermore, the success of younger males suggests that they are more successful in sperm competition.
Biofilm community succession: a neutral perspective.
Woodcock, Stephen; Sloan, William T
2017-05-22
Although biofilms represent one of the dominant forms of life in aqueous environments, our understanding of the assembly and development of their microbial communities remains relatively poor. In recent years, several studies have addressed this and have extended the concepts of succession theory in classical ecology into microbial systems. From these datasets, niche-based conceptual models have been developed explaining observed biodiversity patterns and their dynamics. These models have not, however, been formulated mathematically and so remain untested. Here, we further develop spatially resolved neutral community models and demonstrate that these can also explain these patterns and offer alternative explanations of microbial succession. The success of neutral models suggests that stochastic effects alone may have a much greater influence on microbial community succession than previously acknowledged. Furthermore, such models are much more readily parameterised and can be used as the foundation of more complex and realistic models of microbial community succession.
From Data-Sharing to Model-Sharing: SCEC and the Development of Earthquake System Science (Invited)
NASA Astrophysics Data System (ADS)
Jordan, T. H.
2009-12-01
Earthquake system science seeks to construct system-level models of earthquake phenomena and use them to predict emergent seismic behavior—an ambitious enterprise that requires high degree of interdisciplinary, multi-institutional collaboration. This presentation will explore model-sharing structures that have been successful in promoting earthquake system science within the Southern California Earthquake Center (SCEC). These include disciplinary working groups to aggregate data into community models; numerical-simulation working groups to investigate system-specific phenomena (process modeling) and further improve the data models (inverse modeling); and interdisciplinary working groups to synthesize predictive system-level models. SCEC has developed a cyberinfrastructure, called the Community Modeling Environment, that can distribute the community models; manage large suites of numerical simulations; vertically integrate the hardware, software, and wetware needed for system-level modeling; and promote the interactions among working groups needed for model validation and refinement. Various socio-scientific structures contribute to successful model-sharing. Two of the most important are “communities of trust” and collaborations between government and academic scientists on mission-oriented objectives. The latter include improvements of earthquake forecasts and seismic hazard models and the use of earthquake scenarios in promoting public awareness and disaster management.
Thermomechanical Controls on the Success and Failure of Continental Rift Systems
NASA Astrophysics Data System (ADS)
Brune, S.
2017-12-01
Studies of long-term continental rift evolution are often biased towards rifts that succeed in breaking the continent like the North Atlantic, South China Sea, or South Atlantic rifts. However there are many prominent rift systems on Earth where activity stopped before the formation of a new ocean basin such as the North Sea, the West and Central African Rifts, or the West Antarctic Rift System. The factors controlling the success and failure of rifts can be divided in two groups: (1) Intrinsic processes - for instance frictional weakening, lithospheric thinning, shear heating or the strain-dependent growth of rift strength by replacing weak crust with strong mantle. (2) External processes - such as a change of plate divergence rate, the waning of a far-field driving force, or the arrival of a mantle plume. Here I use numerical and analytical modeling to investigate the role of these processes for the success and failure of rift systems. These models show that a change of plate divergence rate under constant force extension is controlled by the non-linearity of lithospheric materials. For successful rifts, a strong increase in divergence velocity can be expected to take place within few million years, a prediction that agrees with independent plate tectonic reconstructions of major Mesozoic and Cenozoic ocean-forming rift systems. Another model prediction is that oblique rifting is mechanically favored over orthogonal rifting, which means that simultaneous deformation within neighboring rift systems of different obliquity and otherwise identical properties will lead to success and failure of the more and less oblique rift, respectively. This can be exemplified by the Cretaceous activity within the Equatorial Atlantic and the West African Rifts that lead to the formation of a highly oblique oceanic spreading center and the failure of the West African Rift System. While in nature the circumstances of rift success or failure may be manifold, simplified numerical and analytical models allow the isolated analysis of various contributing factors and to define a characteristic time scale for each process.
Inheriting Curiosity: Leveraging MBSE to Build Mars2020
NASA Technical Reports Server (NTRS)
Fosse, Elyse; Harmon, Corey; Lefland, Mallory; Castillo, Robert; Devereaux, Ann
2015-01-01
The success of the Jet Propulsion Laboratory's (JPL) Martian mission Mars Science Laboratory (MSL) prompted NASA to challenge JPL to build a second rover, Mars2020. Mars2020 has chosen to infuse Model Based Systems Engineering (MBSE) in pursuit of aiding the design of the Flight System. This paper will derive the motivation for MBSE infusion and will explain the current state of the Mars2020 Flight System Model. Successes in MBSE adoption will be discussed, as will limitations to the methodology.
Simulation of hydrologic influences on wetland ecosystem succession. Master's thesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pompilio, R.A.
1994-09-01
This research focuses on the development of a simulation model to determine the affects of hydrological influences on a wetland ecosystem. The model allows perturbations to the inputs of various wetland data which in turn, influences the successional development of the ecosystem. This research consisted of converting a grassland ecosystem model to one which simulates wetland conditions. The critical factor in determining the success of wetland creation is the hydrology of the system. There are four of the areas of the original model which are affected by the hydrology. The model measures the health or success of the ecosystem throughmore » the measurement of the systems gross plant production, the respiration and the net primary production of biomass. Altering the auxiliary variables of water level and the rate of flow through the system explicitly details the affects hydrologic influences on those production rates. Ten case tests depicting exogenous perturbations of the hydrology were run to identify these affects. Although the tests dealt with the fluctuation of water through the system, any one of the auxiliary variables in the model could be changed to reflect site specific data. Productivity, Hazardous material management, Hazardous material pharmacy.« less
2013-01-01
Background With the increasing prevalence of Picture Archiving and Communication Systems (PACS) in healthcare institutions, there is a growing need to measure their success. However, there is a lack of published literature emphasizing the technical and social factors underlying a successful PACS. Methods An updated Information Systems Success Model was utilized by radiology technologists (RTs) to evaluate the success of PACS at a large medical center in Taiwan. A survey, consisting of 109 questionnaires, was analyzed by Structural Equation Modeling. Results Socio-technical factors (including system quality, information quality, service quality, perceived usefulness, user satisfaction, and PACS dependence) were proven to be effective measures of PACS success. Although the relationship between service quality and perceived usefulness was not significant, other proposed relationships amongst the six measurement parameters of success were all confirmed. Conclusions Managers have an obligation to improve the attributes of PACS. At the onset of its deployment, RTs will have formed their own subjective opinions with regards to its quality (system quality, information quality, and service quality). As these personal concepts are either refuted or reinforced based on personal experiences, RTs will become either satisfied or dissatisfied with PACS, based on their perception of its usefulness or lack of usefulness. A satisfied RT may play a pivotal role in the implementation of PACS in the future. PMID:24053458
A UML model for the description of different brain-computer interface systems.
Quitadamo, Lucia Rita; Abbafati, Manuel; Saggio, Giovanni; Marciani, Maria Grazia; Cardarilli, Gian Carlo; Bianchi, Luigi
2008-01-01
BCI research lacks a universal descriptive language among labs and a unique standard model for the description of BCI systems. This results in a serious problem in comparing performances of different BCI processes and in unifying tools and resources. In such a view we implemented a Unified Modeling Language (UML) model for the description virtually of any BCI protocol and we demonstrated that it can be successfully applied to the most common ones such as P300, mu-rhythms, SCP, SSVEP, fMRI. Finally we illustrated the advantages in utilizing a standard terminology for BCIs and how the same basic structure can be successfully adopted for the implementation of new systems.
ERIC Educational Resources Information Center
Cardak, Osman; Dikmenli, Musa; Saritas, Ozge
2008-01-01
The aim of this study is to research the effect of the 5E instructional model on primary (sixth grade) student success during the circulatory system unit. This study was conducted with 38 students in two different classes by the same researcher in 2006-2007. One of the classes was assigned as the control group and the other as the experimental…
ERIC Educational Resources Information Center
Lin, Tung-Cheng; Chen, Ching-Jen
2012-01-01
Many e-learning studies have evaluated learning attitudes and behaviors, based on TAM. However, a successful e-learning system (ELS) should take both system and information quality into account by applying ISM developed by Delone and McLean. In addition, the acceptance for information system depends on the perceived usefulness and ease of use…
Impact of Doctors' Resistance on Success of Drug Utilization Review System
Choi, Jong Soo; Yun, Seong Hyeon; Kim, Dongsoo
2014-01-01
Objectives The drug utilization review (DUR) system, which checks any conflict event of medications, contributes to improve patient safety. One of the important barriers in its adoption is doctors' resistance. This study aimed to analyze the impacts of doctors' resistance on the success of the DUR system. Methods This study adopted an augmented the DeLone and McLean Information System (D&M IS) Success Model (2003), which used doctors' resistance as a socio-technological measure. This study framework is the same as that of the D&M IS Success Model in that it is based on qualities, such as system, information, and services. The major difference is that this study excluded the variable 'use' because it was not statistically significant for mandatory systems. A survey of doctors who used computers to enter prescriptions was conducted at a Korean tertiary hospital in February 2012. Results This study is very meaningful in that it is the first study to explore the success factors of the DUR system associated with doctors' resistance. Doctors' resistance to the DUR system was not statistically associated with user usefulness, whereas it affected user satisfaction. Conclusions The results indicate that doctors still complain of discomfort in using the DUR system in the outpatient clinical setting, even though they admit that it contributes to patient safety. To mitigate doctors' resistance and raise user satisfaction, more opinions from doctors regarding the DUR system have to be considered and have to be reflected in the system. PMID:24872908
The evaluation system of city's smart growth success rates
NASA Astrophysics Data System (ADS)
Huang, Yifan
2018-04-01
"Smart growth" is to pursue the best integrated perform+-ance of the Economically prosperous, socially Equitable, and Environmentally Sustainable(3E). Firstly, we establish the smart growth evaluation system(SGI) and the sustainable development evaluation system(SDI). Based on the ten principles and the definition of three E's of sustainability. B y using the Z-score method and the principal component analysis method, we evaluate and quantify indexes synthetically. Then we define the success of smart growth as the ratio of the SDI to the SGI composite score growth rate (SSG). After that we select two cities — Canberra and Durres as the objects of our model in view of the model. Based on the development plans and key data of these two cities, we can figure out the success of smart growth. And according to our model, we adjust some of the growth indicators for both cities. Then observe the results before and after adjustment, and finally verify the accuracy of the model.
The Use of High Performance Computing (HPC) to Strengthen the Development of Army Systems
2011-11-01
accurately predicting the supersonic magus effect about spinning cones, ogive- cylinders , and boat-tailed afterbodies. This work led to the successful...successful computer model of the proposed product or system, one can then build prototypes on the computer and study the effects on the performance of...needed. The NRC report discusses the requirements for effective use of such computing power. One needs “models, algorithms, software, hardware
Robert A. Riggs; Robert E. Keane; Norm Cimon; Rachel Cook; Lisa Holsinger; John Cook; Timothy DelCurto; L.Scott Baggett; Donald Justice; David Powell; Martin Vavra; Bridgett Naylor
2015-01-01
Landscape fire succession models (LFSMs) predict spatially-explicit interactions between vegetation succession and disturbance, but these models have yet to fully integrate ungulate herbivory as a driver of their processes. We modified a complex LFSM, FireBGCv2, to include a multi-species herbivory module, GrazeBGC. The system is novel in that it explicitly...
Internet's impact on publishing
NASA Astrophysics Data System (ADS)
Beretta, Giordano B.
1997-04-01
In 1990, the first monochrome print-on-demand (POD) systems wee successfully brought to market. Subsequent color versions have been less successful, in my view mostly because they require a different workflow than traditional systems and the highly skilled specialists have not been trained. This hypothesis is based on the observation that direct-to-plate systems for short run printing, which do not require a new workflow, are quite successful in the market place. The internet and the World Wide Web are the enabling technologies that are fostering a new print model that is very likely to replace color POD before the latter can establish itself. In this model the consumers locate the material they desire from a contents provider, pay through a digital cash clearinghouse, and print the material at their own cost on their local printer. All the basic technologies for this model are in place; the main challenge is to make the workflow sufficiently robust for individual use.
The 1974 AVCR Young Scholar Paper: An Open-System Model of Learning
ERIC Educational Resources Information Center
Winn, William
1975-01-01
Rejecting the cybernetic model of the learner, the author offers an open-system model based on von Bertalanffy's equation for growth of the living organism. The model produces four learning curves, not just the logarithmic curve produced by the successive approximations of the cybernetic model. (Editor)
ERIC Educational Resources Information Center
Pierre, Ashley R.
2012-01-01
DeLone and McLean first introduced a review of information systems success (ISS) literature and proposed the information success model in 1992. The contribution of technology use and acceptance and its influence toward ISS is an area of information systems research that has received significant attention from both researchers and practitioners.…
Conditions for successfully implementing resident-oriented care in nursing homes.
Berkhout, Afke J M B; Boumans, Nicolle P G; Mur, Ingrid; Nijhuis, Frans J N
2009-06-01
This study reports an investigation of the conditions for a successful introduction of a resident-oriented care model on six somatic and psychogeriatric intervention wards in three Dutch nursing homes. This study aims to answer the following research question: 'What are the conditions for successfully implementing resident-oriented care?' To answer the research question, the organisational change process was monitored by using the '7-S' model of Peters and Waterman as a diagnostic framework. Based on this model, the following change characteristics were studied: structure, strategy, systems, staff, skills, style and shared values. Our study involved a one group pretest/post-test design. To measure the conditions for change, we operationalised the factors of the 7-S model serving as a diagnostic framework and studied their presence and nature on the intervention wards. For this purpose qualitative interviews were held with the change agents of the nursing homes and the wards' supervisors. To determine the degree of 'success' of the implementation, we measured the extent to which resident-oriented care was implemented. For this purpose a quantitative questionnaire was filled in by the nurses of the intervention wards. By relating the extent to which resident-oriented care was implemented to the differences in change conditions, we were able to distinguish the 'most' from the 'least' successful intervention ward and so, pointing out the conditions contributing to a successful implementation of resident-oriented care. The results showed that, in contrast to the least successful intervention ward, the most successful intervention ward was characterised by success conditions related to the 7-S model factors strategy, systems, staff and skills. The factor structure did not contribute to the success of the implementation. Success conditions appeared to be related to the ward level and not to the organisational or project level. Especially the supervisors' role appeared to be crucial for a successful implementation.
The von Neumann model of measurement in quantum mechanics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mello, Pier A.
2014-01-08
We describe how to obtain information on a quantum-mechanical system by coupling it to a probe and detecting some property of the latter, using a model introduced by von Neumann, which describes the interaction of the system proper with the probe in a dynamical way. We first discuss single measurements, where the system proper is coupled to one probe with arbitrary coupling strength. The goal is to obtain information on the system detecting the probe position. We find the reduced density operator of the system, and show how Lüders rule emerges as the limiting case of strong coupling. The vonmore » Neumann model is then generalized to two probes that interact successively with the system proper. Now we find information on the system by detecting the position-position and momentum-position correlations of the two probes. The so-called 'Wigner's formula' emerges in the strong-coupling limit, while 'Kirkwood's quasi-probability distribution' is found as the weak-coupling limit of the above formalism. We show that successive measurements can be used to develop a state-reconstruction scheme. Finally, we find a generalized transform of the state and the observables based on the notion of successive measurements.« less
An Inservice Training Model for Using the Classroom FM System.
ERIC Educational Resources Information Center
Van Dyke, Linda
1982-01-01
An inservice training model for successful implementation of FM (Frequency Modulation) transmission systems for hearing impaired students must take into account its purpose and functions, mechanics, and management. (CD)
Phytoplankton succession in recurrently fluctuating environments.
Roelke, Daniel L; Spatharis, Sofie
2015-01-01
Coastal marine systems are affected by seasonal variations in biogeochemical and physical processes, sometimes leading to alternating periods of reproductive growth limitation within an annual cycle. Transitions between these periods can be sudden or gradual. Human activities, such as reservoir construction and interbasin water transfers, influence these processes and can affect the type of transition between resource loading conditions. How such human activities might influence phytoplankton succession is largely unknown. Here, we employ a multispecies, multi-nutrient model to explore how nutrient loading switching mode might affect phytoplankton succession. The model is based on the Monod-relationship, predicting an instantaneous reproductive growth rate from ambient inorganic nutrient concentrations whereas the limiting nutrient at any given time was determined by Liebig's Law of the Minimum. When these relationships are combined with population loss factors, such as hydraulic displacement of cells associated with inflows, a characterization of a species' niche can be achieved through application of the R* conceptual model, thus enabling an ecological interpretation of modeling results. We found that the mode of reversal in resource supply concentrations had a profound effect. When resource supply reversals were sudden, as expected in systems influenced by pulsed inflows or wind-driven mixing events, phytoplankton were characterized by alternating succession dynamics, a phenomenon documented in inland water bodies of temperate latitudes. When resource supply reversals were gradual, as expected in systems influenced by seasonally developing wet and dry seasons, or annually occurring periods of upwelling, phytoplankton dynamics were characterized by mirror-image succession patterns. This phenomenon has not been reported previously in plankton systems but has been observed in some terrestrial plant systems. These findings suggest that a transition from alternating to "mirror-image" succession patterns might arise with continued coastal zone development, with crucial implications for ecosystems dependent on time-sensitive processes, e.g., spawning events and migration patterns.
When more of the same is better
NASA Astrophysics Data System (ADS)
Fontanari, José F.
2016-01-01
Problem solving (e.g., drug design, traffic engineering, software development) by task forces represents a substantial portion of the economy of developed countries. Here we use an agent-based model of cooperative problem-solving systems to study the influence of diversity on the performance of a task force. We assume that agents cooperate by exchanging information on their partial success and use that information to imitate the more successful agent in the system —the model. The agents differ only in their propensities to copy the model. We find that, for easy tasks, the optimal organization is a homogeneous system composed of agents with the highest possible copy propensities. For difficult tasks, we find that diversity can prevent the system from being trapped in sub-optimal solutions. However, when the system size is adjusted to maximize the performance the homogeneous systems outperform the heterogeneous systems, i.e., for optimal performance, sameness should be preferred to diversity.
Modeling the Car Crash Crisis Management System Using HiLA
NASA Astrophysics Data System (ADS)
Hölzl, Matthias; Knapp, Alexander; Zhang, Gefei
An aspect-oriented modeling approach to the Car Crash Crisis Management System (CCCMS) using the High-Level Aspect (HiLA) language is described. HiLA is a language for expressing aspects for UML static structures and UML state machines. In particular, HiLA supports both a static graph transformational and a dynamic approach of applying aspects. Furthermore, it facilitates methodologically turning use case descriptions into state machines: for each main success scenario, a base state machine is developed; all extensions to this main success scenario are covered by aspects. Overall, the static structure of the CCCMS is modeled in 43 classes, the main success scenarios in 13 base machines, the use case extensions in 47 static and 31 dynamic aspects, most of which are instantiations of simple aspect templates.
Ten key principles for successful health systems integration.
Suter, Esther; Oelke, Nelly D; Adair, Carol E; Armitage, Gail D
2009-01-01
Integrated health systems are considered part of the solution to the challenge of sustaining Canada's healthcare system. This systematic literature review was undertaken to guide decision-makers and others to plan for and implement integrated health systems. This review identified 10 universal principles of successfully integrated healthcare systems that may be used by decision-makers to assist with integration efforts. These principles define key areas for restructuring and allow organizational flexibility and adaptation to local context. The literature does not contain a one-size-fits-all model or process for successful integration, nor is there a firm empirical foundation for specific integration strategies and processes.
A Checklist for Successful Quantitative Live Cell Imaging in Systems Biology
Sung, Myong-Hee
2013-01-01
Mathematical modeling of signaling and gene regulatory networks has provided unique insights about systems behaviors for many cell biological problems of medical importance. Quantitative single cell monitoring has a crucial role in advancing systems modeling of molecular networks. However, due to the multidisciplinary techniques that are necessary for adaptation of such systems biology approaches, dissemination to a wide research community has been relatively slow. In this essay, I focus on some technical aspects that are often under-appreciated, yet critical in harnessing live cell imaging methods to achieve single-cell-level understanding and quantitative modeling of molecular networks. The importance of these technical considerations will be elaborated with examples of successes and shortcomings. Future efforts will benefit by avoiding some pitfalls and by utilizing the lessons collectively learned from recent applications of imaging in systems biology. PMID:24709701
Parameter Selection Methods in Inverse Problem Formulation
2010-11-03
clinical data and used for prediction and a model for the reaction of the cardiovascular system to an ergometric workload. Key Words: Parameter selection...model for HIV dynamics which has been successfully validated with clinical data and used for prediction and a model for the reaction of the...recently developed in-host model for HIV dynamics which has been successfully validated with clinical data and used for prediction [4, 8]; b) a global
Tetsuka, Kazuhiro; Ohbuchi, Masato; Tabata, Kenji
2017-09-01
Tissue engineering technology has provided many useful culture models. This article reviews the merits of this technology in a hepatocyte culture system and describes the applications of the sandwich-cultured hepatocyte model in drug discovery. In addition, we also review recent investigations of the utility of the 3-dimensional bioprinted human liver tissue model and spheroid model. Finally, we present the future direction and developmental challenges of a hepatocyte culture model for the successful establishment of a microphysiological system, represented as an organ-on-a-chip and even as a human-on-a-chip. A merit of advanced culture models is their potential use for detecting hepatotoxicity through repeated exposure to chemicals as they allow long-term culture while maintaining hepatocyte functionality. As a future direction, such advanced hepatocyte culture systems can be connected to other tissue models for evaluating tissue-to-tissue interaction beyond cell-to-cell interaction. This combination of culture models could represent parts of the human body in a microphysiological system. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
Majoring in Information Systems: An Examination of Role Model Influence
ERIC Educational Resources Information Center
Akbulut, Asli Y.
2016-01-01
The importance of role models on individuals' academic and career development and success has been widely acknowledged in the literature. The purpose of this study was to understand the influence of role models on students' decisions to major in information systems (IS). Utilizing a model derived from the social cognitive career theory, we…
Porter, Dayna; Hall, Mark; Hartl, Brian; Raevsky, Cathy; Peacock, Roberta; Kraker, David; Walls, Sandra; Brink, Gail
2011-01-01
Mass vaccination clinic staffing models, such as the Centers for Disease Control and Prevention Large-Scale Vaccination Clinic Output and Staff Estimates: An Example, provide guidance on appropriate roles and number of staff for successful mass vaccination clinics within local and state health departments. The Kent County Health Department used this model as a starting point for mass vaccination clinics in response to 2009 H1N1 influenza. In addition to discussion of successful modification of the Centers for Disease Control and Prevention model to maximize local health department mass vaccination clinic efficiency, additional best practices including use of the Incident Command System and a reservation system are provided. Use of the provided modified staffing model and additional best practices will increase the success of health department mass vaccination clinics, and should be considered not only for future public health emergencies, but also for seasonal influenza vaccination campaigns.
SOA governance in healthcare organisations.
Koumaditis, Konstantinos; Themistocleous, Marinos; Vassilakopoulos, Georgios
2013-01-01
Service Oriented Architecture (SOA) is increasingly adopted by many sectors, including healthcare. Due to the nature of healthcare systems there is a need to increase SOA adoption success rates as the non integrated nature of healthcare systems is responsible for medical errors that cause the loss of tens of thousands patients per year. Following our previous research [1] we propose that SOA governance is a critical success factor for SOA success in healthcare. Literature reports multiple SOA governance models that have limitations and they are confusing. In addition to this, there is a lack of healthcare specific SOA governance models. This highlights a literature void and thus the purpose of this paper is to proposed a healthcare specific SOA governance framework.
NASA Astrophysics Data System (ADS)
Hucka, M.
2015-09-01
In common with many fields, including astronomy, a vast number of software tools for computational modeling and simulation are available today in systems biology. This wealth of resources is a boon to researchers, but it also presents interoperability problems. Despite working with different software tools, researchers want to disseminate their work widely as well as reuse and extend the models of other researchers. This situation led in the year 2000 to an effort to create a tool-independent, machine-readable file format for representing models: SBML, the Systems Biology Markup Language. SBML has since become the de facto standard for its purpose. Its success and general approach has inspired and influenced other community-oriented standardization efforts in systems biology. Open standards are essential for the progress of science in all fields, but it is often difficult for academic researchers to organize successful community-based standards. I draw on personal experiences from the development of SBML and summarize some of the lessons learned, in the hope that this may be useful to other groups seeking to develop open standards in a community-oriented fashion.
ERIC Educational Resources Information Center
Redmond, M. William, Jr.
2011-01-01
The purpose of this study is to develop a preadmission predictive model of student success for prospective first-time African American college applicants at a predominately White four-year public institution within the Pennsylvania State System of Higher Education. This model will use two types of variables. They are (a) cognitive variables (i.e.,…
Automatic translation of digraph to fault-tree models
NASA Technical Reports Server (NTRS)
Iverson, David L.
1992-01-01
The author presents a technique for converting digraph models, including those models containing cycles, to a fault-tree format. A computer program which automatically performs this translation using an object-oriented representation of the models has been developed. The fault-trees resulting from translations can be used for fault-tree analysis and diagnosis. Programs to calculate fault-tree and digraph cut sets and perform diagnosis with fault-tree models have also been developed. The digraph to fault-tree translation system has been successfully tested on several digraphs of varying size and complexity. Details of some representative translation problems are presented. Most of the computation performed by the program is dedicated to finding minimal cut sets for digraph nodes in order to break cycles in the digraph. Fault-trees produced by the translator have been successfully used with NASA's Fault-Tree Diagnosis System (FTDS) to produce automated diagnostic systems.
NASA Astrophysics Data System (ADS)
Pattanayak, Sujata; Mohanty, U. C.
2018-06-01
The paper intends to present the development of the extended weather research forecasting data assimilation (WRFDA) system in the framework of the non-hydrostatic mesoscale model core of weather research forecasting system (WRF-NMM), as an imperative aspect of numerical modeling studies. Though originally the WRFDA provides improved initial conditions for advanced research WRF, we have successfully developed a unified WRFDA utility that can be used by the WRF-NMM core, as well. After critical evaluation, it has been strategized to develop a code to merge WRFDA framework and WRF-NMM output. In this paper, we have provided a few selected implementations and initial results through single observation test, and background error statistics like eigenvalues, eigenvector and length scale among others, which showcase the successful development of extended WRFDA code for WRF-NMM model. Furthermore, the extended WRFDA system is applied for the forecast of three severe cyclonic storms: Nargis (27 April-3 May 2008), Aila (23-26 May 2009) and Jal (4-8 November 2010) formed over the Bay of Bengal. Model results are compared and contrasted within the analysis fields and later on with high-resolution model forecasts. The mean initial position error is reduced by 33% with WRFDA as compared to GFS analysis. The vector displacement errors in track forecast are reduced by 33, 31, 30 and 20% to 24, 48, 72 and 96 hr forecasts respectively, in data assimilation experiments as compared to control run. The model diagnostics indicates successful implementation of WRFDA within the WRF-NMM system.
NASA Astrophysics Data System (ADS)
Malard, J. J.; Adamowski, J. F.; Wang, L. Y.; Rojas, M.; Carrera, J.; Gálvez, J.; Tuy, H. A.; Melgar-Quiñonez, H.
2015-12-01
The modelling of the impacts of climate change on agriculture requires the inclusion of socio-economic factors. However, while cropping models and economic models of agricultural systems are common, dynamically coupled socio-economic-biophysical models have not received as much success. A promising methodology for modelling the socioeconomic aspects of coupled natural-human systems is participatory system dynamics modelling, in which stakeholders develop mental maps of the socio-economic system that are then turned into quantified simulation models. This methodology has been successful in the water resources management field. However, while the stocks and flows of water resources have also been represented within the system dynamics modelling framework and thus coupled to the socioeconomic portion of the model, cropping models are ill-suited for such reformulation. In addition, most of these system dynamics models were developed without stakeholder input, limiting the scope for the adoption and implementation of their results. We therefore propose a new methodology for the analysis of climate change variability on agroecosystems which uses dynamically coupled system dynamics (socio-economic) and biophysical (cropping) models to represent both physical and socioeconomic aspects of the agricultural system, using two case studies (intensive market-based agricultural development versus subsistence crop-based development) from rural Guatemala. The system dynamics model component is developed with relevant governmental and NGO stakeholders from rural and agricultural development in the case study regions and includes such processes as education, poverty and food security. Common variables with the cropping models (yield and agricultural management choices) are then used to dynamically couple the two models together, allowing for the analysis of the agroeconomic system's response to and resilience against various climatic and socioeconomic shocks.
Digital-flutter-suppression-system investigations for the active flexible wing wind-tunnel model
NASA Technical Reports Server (NTRS)
Perry, Boyd, III; Mukhopadhyay, Vivek; Hoadley, Sherwood Tiffany; Cole, Stanley R.; Buttrill, Carey S.
1990-01-01
Active flutter suppression control laws were designed, implemented, and tested on an aeroelastically-scaled wind-tunnel model in the NASA Langley Transonic Dynamics Tunnel. One of the control laws was successful in stabilizing the model while the dynamic pressure was increased to 24 percent greater than the measured open-loop flutter boundary. Other accomplishments included the design, implementation, and successful operation of a one-of-a-kind digital controller, the design and use of two simulation methods to support the project, and the development and successful use of a methodology for online controller performance evaluation.
Digital-flutter-suppression-system investigations for the active flexible wing wind-tunnel model
NASA Technical Reports Server (NTRS)
Perry, Boyd, III; Mukhopadhyay, Vivek; Hoadley, Sherwood T.; Cole, Stanley R.; Buttrill, Carey S.; Houck, Jacob A.
1990-01-01
Active flutter suppression control laws were designed, implemented, and tested on an aeroelastically-scaled wind tunnel model in the NASA Langley Transonic Dynamics Tunnel. One of the control laws was successful in stabilizing the model while the dynamic pressure was increased to 24 percent greater than the measured open-loop flutter boundary. Other accomplishments included the design, implementation, and successful operation of a one-of-a-kind digital controller, the design and use of two simulation methods to support the project, and the development and successful use of a methodology for on-line controller performance evaluation.
A new approach to design and use of management information.
Daft, R L; MacIntosh, N B
1978-01-01
Information, that is both accurate and timely, is probably the most important resource needed by managers to make sound decisions regarding the problems and issues facing their organizations. Unfortunately, sophisticated information systems often fail to meet this need. Managers complain that the data produced by information systems arrive too late, are too general and lack accuracy. Daft and MacIntosh studied the system problems of a number of organizations, discovering that understanding their work activities is critical to the design of successful information systems. The authors also considered the volume of information, preciseness of information and the way in which it is handled by users to develop a model describing information systems. The article illustrates how the model was applied successfully to four case situations.
The Consumer Health Information System Adoption Model.
Monkman, Helen; Kushniruk, Andre W
2015-01-01
Derived from overlapping concepts in consumer health, a consumer health information system refers to any of the broad range of applications, tools, and educational resources developed to empower consumers with knowledge, techniques, and strategies, to manage their own health. As consumer health information systems become increasingly popular, it is important to explore the factors that impact their adoption and success. Accumulating evidence indicates a relationship between usability and consumers' eHealth Literacy skills and the demands consumer HISs place on their skills. Here, we present a new model called the Consumer Health Information System Adoption Model, which depicts both consumer eHealth literacy skills and system demands on eHealth literacy as moderators with the potential to affect the strength of relationship between usefulness and usability (predictors of usage) and adoption, value, and successful use (actual usage outcomes). Strategies for aligning these two moderating factors are described.
The Impact of Programming Experience on Successfully Learning Systems Analysis and Design
ERIC Educational Resources Information Center
Wong, Wang-chan
2015-01-01
In this paper, the author reports the results of an empirical study on the relationship between a student's programming experience and their success in a traditional Systems Analysis and Design (SA&D) class where technical skills such as dataflow analysis and entity relationship data modeling are covered. While it is possible to teach these…
ERIC Educational Resources Information Center
Broadbent, Jaclyn
2016-01-01
Previous studies have investigated the association between the frequency of student learning management system (LMS) use (logins, discussion board use, resources used, etc.) and academic achievement. These studies indicate that low LMS use by students is likely to result in less academic success. However, these models fail to take into account…
Zhai, Peng-Wang; Hu, Yongxiang; Trepte, Charles R; Lucker, Patricia L
2009-02-16
A vector radiative transfer model has been developed for coupled atmosphere and ocean systems based on the Successive Order of Scattering (SOS) Method. The emphasis of this study is to make the model easy-to-use and computationally efficient. This model provides the full Stokes vector at arbitrary locations which can be conveniently specified by users. The model is capable of tracking and labeling different sources of the photons that are measured, e.g. water leaving radiances and reflected sky lights. This model also has the capability to separate florescence from multi-scattered sunlight. The delta - fit technique has been adopted to reduce computational time associated with the strongly forward-peaked scattering phase matrices. The exponential - linear approximation has been used to reduce the number of discretized vertical layers while maintaining the accuracy. This model is developed to serve the remote sensing community in harvesting physical parameters from multi-platform, multi-sensor measurements that target different components of the atmosphere-oceanic system.
NASA Astrophysics Data System (ADS)
Miller, R.
2015-12-01
Following the success of the implicit particle filter in twin experiments with a shallow water model of the nearshore environment, the planned next step is application to the intensive Sandy Duck data set, gathered at Duck, NC. Adaptation of the present system to the Sandy Duck data set will require construction and evaluation of error models for both the model and the data, as well as significant modification of the system to allow for the properties of the data set. Successful implementation of the particle filter promises to shed light on the details of the capabilities and limitations of shallow water models of the nearshore ocean relative to more detailed models. Since the shallow water model admits distinct dynamical regimes, reliable parameter estimation will be important. Previous work by other groups give cause for optimism. In this talk I will describe my progress toward implementation of the new system, including problems solved, pitfalls remaining and preliminary results
The Value of Successful MBSE Adoption
NASA Technical Reports Server (NTRS)
Parrott, Edith
2016-01-01
The value of successful adoption of Model Based System Engineering (MBSE) practices is hard to quantify. Most engineers and project managers look at the success in terms of cost. But there are other ways to quantify the value of MBSE and the steps necessary to achieve adoption. The Glenn Research Center (GRC) has been doing Model-Based Engineering (design, structural, etc.) for years, but the system engineering side has not. Since 2010, GRC has been moving from documents centric to MBSE/SysML. Project adoption of MBSE has been slow, but is steadily increasing in both MBSE usage and complexity of generated products. Sharing of knowledge of lessons learned in the implementation of MBSE/SysML is key for others who want to be successful. Along with GRC's implementation, NASA is working hard to increase the successful implementation of MBSE across all the other centers by developing guidelines, templates and libraries for projects to utilize. This presentation will provide insight into recent GRC and NASA adoption efforts, lessons learned and best practices.
Mehrtak, Mohamad; Vatankhah, Soodabeh; Delgoshaei, Bahram; Gholipour, Arian
2014-01-01
Background: Succession planning promotes the culture of private ownership, staff loyalty to the organization and develops organizational commitment, and increases organizational stability. The study was conducted to examine the status of succession planning in the Iranian health system in order to highlight the key concepts, provide new insight, and attract the attention of senior managers of the Ministry of Health and Medical Education to the importance of succession planning in achieving organizational goals. Methods: In a qualitative study with a framework analysis approach, semi-structured interviews were conducted with a sample selected using purposive and snowball sampling procedure. The MAXQDA-10 was used to apply the codes and manage the data. The codes were extracted using inductive and deductive methods. Results: Fourteen themes and six main subthemes were identified, including planning, organizational culture, system approach, competency model, career path, and senior managers. Our findings indicate a lack of succession planning in the Iranian health system. Conclusion: lack of succession planning could lead to inefficiency and ineffectiveness in health services provision. Implementation of succession planning could maximize human resources utilization. PMID:25168998
Mehrtak, Mohamad; Vatankhah, Soodabeh; Delgoshaei, Bahram; Gholipour, Arian
2014-05-30
Succession planning promotes the culture of private ownership, staff loyalty to the organization and develops organizational commitment, and increases organizational stability. The study was conducted to examine the status of succession planning in the Iranian health system in order to highlight the key concepts, provide new insight, and attract the attention of senior managers of the Ministry of Health and Medical Education to the importance of succession planning in achieving organizational goals. In a qualitative study with a framework analysis approach, semi-structured interviews were conducted with a sample selected using purposive and snowball sampling procedure. The MAXQDA-10 was used to apply the codes and manage the data. The codes were extracted using inductive and deductive methods. Fourteen themes and six main subthemes were identified, including planning, organizational culture, system approach, competency model, career path, and senior managers. Our findings indicate a lack of succession planning in the Iranian health system. lack of succession planning could lead to inefficiency and ineffectiveness in health services provision. Implementation of succession planning could maximize human resources utilization.
Evaluating the success of an emergency response medical information system.
Petter, Stacie; Fruhling, Ann
2011-07-01
STATPack™ is an information system used to aid in the diagnosis of pathogens in hospitals and state public health laboratories. STATPack™ is used as a communication and telemedicine diagnosis tool during emergencies. This paper explores the success of this emergency response medical information system (ERMIS) using a well-known framework of information systems success developed by DeLone and McLean. Using an online survey, the entire population of STATPack™ users evaluated the success of the information system by considering system quality, information quality, system use, intention to use, user satisfaction, individual impact, and organizational impact. The results indicate that the overall quality of this ERMIS (i.e., system quality, information quality, and service quality) has a positive impact on both user satisfaction and intention to use the system. However, given the nature of ERMIS, overall quality does not necessarily predict use of the system. Moreover, the user's satisfaction with the information system positively affected the intention to use the system. User satisfaction, intention to use, and system use had a positive influence on the system's impact on the individual. Finally, the organizational impacts of the system were positively influenced by use of the system and the system's individual impact on the user. The results of the study demonstrate how to evaluate the success of an ERMIS as well as introduce potential changes in how one applies the DeLone and McLean success model in an emergency response medical information system context. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Multi-state succession in wetlands: a novel use of state and transition models
Zweig, Christa L.; Kitchens, Wiley M.
2009-01-01
The complexity of ecosystems and mechanisms of succession are often simplified by linear and mathematical models used to understand and predict system behavior. Such models often do not incorporate multivariate, nonlinear feedbacks in pattern and process that include multiple scales of organization inherent within real-world systems. Wetlands are ecosystems with unique, nonlinear patterns of succession due to the regular, but often inconstant, presence of water on the landscape. We develop a general, nonspatial state and transition (S and T) succession conceptual model for wetlands and apply the general framework by creating annotated succession/management models and hypotheses for use in impact analysis on a portion of an imperiled wetland. The S and T models for our study area, Water Conservation Area 3A South (WCA3), Florida, USA, included hydrologic and peat depth values from multivariate analyses and classification and regression trees. We used the freeware Vegetation Dynamics Development Tool as an exploratory application to evaluate our S and T models with different management actions (equal chance [a control condition], deeper conditions, dry conditions, and increased hydrologic range) for three communities: slough, sawgrass (Cladium jamaicense), and wet prairie. Deeper conditions and increased hydrologic range behaved similarly, with the transition of community states to deeper states, particularly for sawgrass and slough. Hydrology is the primary mechanism for multi-state transitions within our study period, and we show both an immediate and lagged effect on vegetation, depending on community state. We consider these S and T succession models as a fraction of the framework for the Everglades. They are hypotheses for use in adaptive management, represent the community response to hydrology, and illustrate which aspects of hydrologic variability are important to community structure. We intend for these models to act as a foundation for further restoration management and experimentation which will refine transition and threshold concepts.
McAlearney, Ann Scheck; Hefner, Jennifer L; Sieck, Cynthia; Rizer, Milisa; Huerta, Timothy R
2014-07-01
While electronic health record (EHR) systems have potential to drive improvements in healthcare, a majority of EHR implementations fall short of expectations. Shortcomings in implementations are often due to organizational issues around the implementation process rather than technological problems. Evidence from both the information technology and healthcare management literature can be applied to improve the likelihood of implementation success, but the translation of this evidence into practice has not been widespread. Our objective was to comprehensively study and synthesize best practices for managing ambulatory EHR system implementation in healthcare organizations, highlighting applicable management theories and successful strategies. We held 45 interviews with key informants in six U.S. healthcare organizations purposively selected based on reported success with ambulatory EHR implementation. We also conducted six focus groups comprised of 37 physicians. Interview and focus group transcripts were analyzed using both deductive and inductive methods to answer research questions and explore emergent themes. We suggest that successful management of ambulatory EHR implementation can be guided by the Plan-Do-Study-Act (PDSA) quality improvement (QI) model. While participants did not acknowledge nor emphasize use of this model, we found evidence that successful implementation practices could be framed using the PDSA model. Additionally, successful sites had three strategies in common: 1) use of evidence from published health information technology (HIT) literature emphasizing implementation facilitators; 2) focusing on workflow; and 3) incorporating critical management factors that facilitate implementation. Organizations seeking to improve ambulatory EHR implementation processes can use frameworks such as the PDSA QI model to guide efforts and provide a means to formally accommodate new evidence over time. Implementing formal management strategies and incorporating new evidence through the PDSA model is a key element of evidence-based management and a crucial way for organizations to position themselves to proactively address implementation and use challenges before they are exacerbated. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
A Comparative Study of Successful Central Nervous System Drugs Using Molecular Modeling
ERIC Educational Resources Information Center
Kim, Hyosub; Sulaimon, Segun; Menezes, Sandra; Son, Anne; Menezes, Warren J. C.
2011-01-01
Molecular modeling is a powerful tool used for three-dimensional visualization and for exploring electrostatic forces involved in drug transport. This tool enhances student understanding of structure-property relationships, as well as actively engaging them in class. Molecular modeling of several central nervous system (CNS) drugs is used to…
Setting Strategic Directions Using Critical Success Factors.
ERIC Educational Resources Information Center
Bourne, Bonnie; Gates, Larry; Cofer, James
2000-01-01
Describes implementation of a system-level planning model focused on institutional improvement and effectiveness at the University of Missouri. Details implementation of three phases of the strategic planning model (strategic analysis, strategic thinking/decision-making, and campus outreach/systems administration planning); identifies critical…
Energy Systems Integration News | Energy Systems Integration Facility |
Power Grid Simulation at a Distance NREL and Idaho National Laboratory (INL) have successfully connected of Power System Modeling and Simulation: "Bus.py: A GridLAB-D Communication Interface for Smart Modeling and Simulation" session at the IEEE PES General Meeting in Denver, Colorado, from 15 p.m. on
Agent-Based Modeling in Systems Pharmacology.
Cosgrove, J; Butler, J; Alden, K; Read, M; Kumar, V; Cucurull-Sanchez, L; Timmis, J; Coles, M
2015-11-01
Modeling and simulation (M&S) techniques provide a platform for knowledge integration and hypothesis testing to gain insights into biological systems that would not be possible a priori. Agent-based modeling (ABM) is an M&S technique that focuses on describing individual components rather than homogenous populations. This tutorial introduces ABM to systems pharmacologists, using relevant case studies to highlight how ABM-specific strengths have yielded success in the area of preclinical mechanistic modeling.
Nonlinear filtering techniques for noisy geophysical data: Using big data to predict the future
NASA Astrophysics Data System (ADS)
Moore, J. M.
2014-12-01
Chaos is ubiquitous in physical systems. Within the Earth sciences it is readily evident in seismology, groundwater flows and drilling data. Models and workflows have been applied successfully to understand and even to predict chaotic systems in other scientific fields, including electrical engineering, neurology and oceanography. Unfortunately, the high levels of noise characteristic of our planet's chaotic processes often render these frameworks ineffective. This contribution presents techniques for the reduction of noise associated with measurements of nonlinear systems. Our ultimate aim is to develop data assimilation techniques for forward models that describe chaotic observations, such as episodic tremor and slip (ETS) events in fault zones. A series of nonlinear filters are presented and evaluated using classical chaotic systems. To investigate whether the filters can successfully mitigate the effect of noise typical of Earth science, they are applied to sunspot data. The filtered data can be used successfully to forecast sunspot evolution for up to eight years (see figure).
Dynamic Gate Product and Artifact Generation from System Models
NASA Technical Reports Server (NTRS)
Jackson, Maddalena; Delp, Christopher; Bindschadler, Duane; Sarrel, Marc; Wollaeger, Ryan; Lam, Doris
2011-01-01
Model Based Systems Engineering (MBSE) is gaining acceptance as a way to formalize systems engineering practice through the use of models. The traditional method of producing and managing a plethora of disjointed documents and presentations ("Power-Point Engineering") has proven both costly and limiting as a means to manage the complex and sophisticated specifications of modern space systems. We have developed a tool and method to produce sophisticated artifacts as views and by-products of integrated models, allowing us to minimize the practice of "Power-Point Engineering" from model-based projects and demonstrate the ability of MBSE to work within and supersede traditional engineering practices. This paper describes how we have created and successfully used model-based document generation techniques to extract paper artifacts from complex SysML and UML models in support of successful project reviews. Use of formal SysML and UML models for architecture and system design enables production of review documents, textual artifacts, and analyses that are consistent with one-another and require virtually no labor-intensive maintenance across small-scale design changes and multiple authors. This effort thus enables approaches that focus more on rigorous engineering work and less on "PowerPoint engineering" and production of paper-based documents or their "office-productivity" file equivalents.
Broquet, Thomas; Barranger, Audrey; Billard, Emmanuelle; Bestin, Anastasia; Berger, Rémy; Honnaert, Gaelle; Viard, Frédérique
2015-09-01
Sequential hermaphroditism is adaptive when the reproductive value of an individual varies with size or age, and this relationship differs between males and females. In this case, theory shows that the lifetime reproductive output of an individual is increased by changing sex (a hypothesis referred to as the size-advantage model). Sex-linked differences in size-fitness curves can stem from differential costs of reproduction, the mating system, and differences in growth and mortality between sexes. Detailed empirical data is required to disentangle the relative roles of each of these factors within the theory. Quantitative data are also needed to explore the role of sperm storage, which has not yet been considered with sequential hermaphrodites. Using experimental rearing and paternity assignment, we report relationships between size and reproductive success of Crepidula fornicata, a protandrous (male-first) gastropod. Male reproductive success increased with size due to the polygamous system and stacking behavior of the species, but females nonetheless had greater reproductive success than males of the same size, in agreement with the size-advantage theory. Sperm storage appeared to be a critical determinant of success for both sexes, and modeling the effect of sperm storage showed that it could potentially accelerate sex change in protandrous species.
ERIC Educational Resources Information Center
Karp, Melinda Mechur; Lundy-Wagner, Valerie
2015-01-01
"Collective impact" is a new place-based model of educational and social intervention that aims to shift responsibility for improvement in outcomes from individual organizations to entire systems that affect the lives of people in a particular location. CCRC's "Corridors of College Success Series" provides insights into…
Measuring mobile patient safety information system success: an empirical study.
Jen, Wen-Yuan; Chao, Chia-Cheng
2008-10-01
The Health Risk Reminders and Surveillance (HRRS) system was designed to deliver critical abnormal test results of severely ill patients from Laboratory, Radiology, and Pathology departments to physicians within 5 min using cell phone text messages. This paper explores the success of the HRRS system. This study employed an augmented version of the DeLone and McLean IS success model. Seven variables (system quality, information quality, system use, user satisfaction, mobile healthcare anxiety, impact on the individual and impact on the organization) were used to evaluate the success of the HRRS system. The interrelationships between the seven variables were hypothesized and the hypotheses were empirically tested. The results indicate that the information quality of the HRRS system is positively associated with both system use and user satisfaction. In addition, system use is positively associated with user satisfaction, which is also positively associated with mobile healthcare anxiety. Moreover, results indicate that impact on the individual is positively associated with both user satisfaction and mobile healthcare anxiety. Finally, the impact of the organization is positively associated with impact on the individual. The results of the study provide an expanded understanding of the factors that contribute to mobile patient safety information system (IS) success. Implications of the relationship between system use and physician mobile healthcare anxiety are discussed.
Experiences and Lessons from Urban Health Insurance Reform in China.
Xin, Haichang
2016-08-01
Health care systems often face competing goals and priorities, which make reforms challenging. This study analyzed factors influencing the success of a health care system based on urban health insurance reform evolution in China, and offers recommendations for improvement. Findings based on health insurance reform strategies and mechanisms that did or did not work can effectively inform improvement of health insurance system design and practice, and overall health care system performance, including equity, efficiency, effectiveness, cost, finance, access, and coverage, both in China and other countries. This study is the first to use historical comparison to examine the success and failure of China's health care system over time before and after the economic reform in the 1980s. This study is also among the first to analyze the determinants of Chinese health system effectiveness by relating its performance to both technical reasons within the health system and underlying nontechnical characteristics outside the health system, including socioeconomics, politics, culture, values, and beliefs. In conclusion, a health insurance system is successful when it fits its social environment, economic framework, and cultural context, which translates to congruent health care policies, strategies, organization, and delivery. No health system can survive without its deeply rooted socioeconomic environment and cultural context. That is why one society should be cautious not to radically switch from a successful model to an entirely different one over time. There is no perfect health system model suitable for every population-only appropriate ones for specific nations and specific populations at the right place and right time. (Population Health Management 2016;19:291-297).
Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix®.
Caccavo, D; Barba, A A; d'Amore, M; De Piano, R; Lamberti, G; Rossi, A; Colombo, P
2017-12-01
The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used asa fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped. Copyright © 2017 Elsevier B.V. All rights reserved.
2017-06-01
The Naval Postgraduate School has developed a competency model for the systems engineering profession and is implementing a tool to support high...stakes human resource functions for the U.S. Army. A systems engineering career competency model (SECCM), recently developed by the Navy and verified by...the Office of Personnel Management (OPM), defines the critical competencies for successful performance as a systems engineer at each general schedule
Lü, Na; Ni, Jian
2013-01-01
By using spatially explicit landscape model (LANDIS 6.0 PRO), and parameterized this model with the long-term research and observation data of Tiantong National Station of Forest Eco-system Observation and Research, this paper simulated the natural succession of evergreen broad-leaved forest in Tiantong National Forest park, Zhejiang Province in the future 500 years, analyzed the spatial distribution and age structure of dominant species and major landscapes, and explored the succession pattern of the evergreen broad-leaved forest. In the park, the species alternation mostly occurred before the stage of evergreen broad-leaved forest. Pinus massoniana, Quercus fabric, and Liquidambar formosana occupied a large proportion during the early succession, but gradually disappeared with the succession process. Schima superba and Castanopsis fargesii took the main advantage in late succession, and developed to the climax community. Under the conditions without disturbances, the community was mainly composed of young forests in the early succession, and of mature or over-mature forests in the late succession, implying the insufficient regeneration ability of the community. LANDIS model could be used for simulating the landscape dynamics of evergreen broad-leaved forest in eastern China. In the future research, both the model structure and the model parameters should be improved, according to the complexity and diversity of subtropical evergreen broad-leaved forest.
Integration of Advanced Probabilistic Analysis Techniques with Multi-Physics Models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cetiner, Mustafa Sacit; none,; Flanagan, George F.
2014-07-30
An integrated simulation platform that couples probabilistic analysis-based tools with model-based simulation tools can provide valuable insights for reactive and proactive responses to plant operating conditions. The objective of this work is to demonstrate the benefits of a partial implementation of the Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Detailed Framework Specification through the coupling of advanced PRA capabilities and accurate multi-physics plant models. Coupling a probabilistic model with a multi-physics model will aid in design, operations, and safety by providing a more accurate understanding of plant behavior. This represents the first attempt at actually integrating these two typesmore » of analyses for a control system used for operations, on a faster than real-time basis. This report documents the development of the basic communication capability to exchange data with the probabilistic model using Reliability Workbench (RWB) and the multi-physics model using Dymola. The communication pathways from injecting a fault (i.e., failing a component) to the probabilistic and multi-physics models were successfully completed. This first version was tested with prototypic models represented in both RWB and Modelica. First, a simple event tree/fault tree (ET/FT) model was created to develop the software code to implement the communication capabilities between the dynamic-link library (dll) and RWB. A program, written in C#, successfully communicates faults to the probabilistic model through the dll. A systems model of the Advanced Liquid-Metal Reactor–Power Reactor Inherently Safe Module (ALMR-PRISM) design developed under another DOE project was upgraded using Dymola to include proper interfaces to allow data exchange with the control application (ConApp). A program, written in C+, successfully communicates faults to the multi-physics model. The results of the example simulation were successfully plotted.« less
ERIC Educational Resources Information Center
Shin, Won Sug; Kang, Minseok
2015-01-01
This study investigates online students' acceptance of mobile learning and its influence on learning achievement using an information system success and extended technology acceptance model (TAM). Structural equation modeling was used to test the structure of individual, social, and systemic factors influencing mobile learning's acceptance, and…
System Identification for the Clipper Liberty C96 Wind Turbine
NASA Astrophysics Data System (ADS)
Showers, Daniel
System identification techniques are powerful tools that help improve modeling capabilities of real world dynamic systems. These techniques are well established and have been successfully used on countless systems in many areas. However, wind turbines provide a unique challenge for system identification because of the difficulty in measuring its primary input: wind. This thesis first motivates the problem by demonstrating the challenges with wind turbine system identification using both simulations and real data. It then suggests techniques toward successfully identifying a dynamic wind turbine model including the notion of an effective wind speed and how it might be measured. Various levels of simulation complexity are explored for insights into calculating an effective wind speed. In addition, measurements taken from the University of Minnesota's Clipper Liberty C96 research wind turbine are used for a preliminary investigation into the effective wind speed calculation and system identification of a real world wind turbine.
Human factors systems approach to healthcare quality and patient safety
Carayon, Pascale; Wetterneck, Tosha B.; Rivera-Rodriguez, A. Joy; Hundt, Ann Schoofs; Hoonakker, Peter; Holden, Richard; Gurses, Ayse P.
2013-01-01
Human factors systems approaches are critical for improving healthcare quality and patient safety. The SEIPS (Systems Engineering Initiative for Patient Safety) model of work system and patient safety is a human factors systems approach that has been successfully applied in healthcare research and practice. Several research and practical applications of the SEIPS model are described. Important implications of the SEIPS model for healthcare system and process redesign are highlighted. Principles for redesigning healthcare systems using the SEIPS model are described. Balancing the work system and encouraging the active and adaptive role of workers are key principles for improving healthcare quality and patient safety. PMID:23845724
Successful Strategies: Building a School-to-Careers System.
ERIC Educational Resources Information Center
Thiers, Naomi, Ed.
The following papers are included: "Building a Broad-Based Partnership" (Randy Wallace); "Creating a Partnership Agreement" (M. Amos Clifford, Robyn Flores); "Forming True Partnerships with Employers" (Lee W. Sloan); "Choosing a Model for Your School-to-Careers System" (Patty Williamson); "Case Study: Career Academy Model" (Shirley Earlise…
Object extraction in photogrammetric computer vision
NASA Astrophysics Data System (ADS)
Mayer, Helmut
This paper discusses state and promising directions of automated object extraction in photogrammetric computer vision considering also practical aspects arising for digital photogrammetric workstations (DPW). A review of the state of the art shows that there are only few practically successful systems on the market. Therefore, important issues for a practical success of automated object extraction are identified. A sound and most important powerful theoretical background is the basis. Here, we particularly point to statistical modeling. Testing makes clear which of the approaches are suited best and how useful they are for praxis. A key for commercial success of a practical system is efficient user interaction. As the means for data acquisition are changing, new promising application areas such as extremely detailed three-dimensional (3D) urban models for virtual television or mission rehearsal evolve.
NASA Astrophysics Data System (ADS)
Turner, M. A.; Miller, S.; Gregory, A.; Cadol, D. D.; Stone, M. C.; Sheneman, L.
2016-12-01
We present the Coupled RipCAS-DFLOW (CoRD) modeling system created to encapsulate the workflow to analyze the effects of stream flooding on vegetation succession. CoRD provides an intuitive command-line and web interface to run DFLOW and RipCAS in succession over many years automatically, which is a challenge because, for our application, DFLOW must be run on a supercomputing cluster via the PBS job scheduler. RipCAS is a vegetation succession model, and DFLOW is a 2D open channel flow model. Data adaptors have been developed to seamlessly connect DFLOW output data to be RipCAS inputs, and vice-versa. CoRD provides automated statistical analysis and visualization, plus automatic syncing of input and output files and model run metadata to the hydrological data management system HydroShare using its excellent Python REST client. This combination of technologies and data management techniques allows the results to be shared with collaborators and eventually published. Perhaps most importantly, it allows results to be easily reproduced via either the command-line or web user interface. This system is a result of collaboration between software developers and hydrologists participating in the Western Consortium for Watershed Analysis, Visualization, and Exploration (WC-WAVE). Because of the computing-intensive nature of this particular workflow, including automating job submission/monitoring and data adaptors, software engineering expertise is required. However, the hydrologists provide the software developers with a purpose and ensure a useful, intuitive tool is developed. Our hydrologists contribute software, too: RipCAS was developed from scratch by hydrologists on the team as a specialized, open-source version of the Computer Aided Simulation Model for Instream Flow and Riparia (CASiMiR) vegetation model; our hydrologists running DFLOW provided numerous examples and help with the supercomputing system. This project is written in Python, a popular language in the geosciences and a good beginner programming language, and is completely open source. It can be accessed at https://github.com/VirtualWatershed/CoRD with documentation available at http://virtualwatershed.github.io/CoRD. These facts enable continued development and use beyond the involvement of the current authors.
NASA Astrophysics Data System (ADS)
Selvy, Brian M.; Claver, Charles; Willman, Beth; Petravick, Don; Johnson, Margaret; Reil, Kevin; Marshall, Stuart; Thomas, Sandrine; Lotz, Paul; Schumacher, German; Lim, Kian-Tat; Jenness, Tim; Jacoby, Suzanne; Emmons, Ben; Axelrod, Tim
2016-08-01
We† provide an overview of the Model Based Systems Engineering (MBSE) language, tool, and methodology being used in our development of the Operational Plan for Large Synoptic Survey Telescope (LSST) operations. LSST's Systems Engineering (SE) team is using a model-based approach to operational plan development to: 1) capture the topdown stakeholders' needs and functional allocations defining the scope, required tasks, and personnel needed for operations, and 2) capture the bottom-up operations and maintenance activities required to conduct the LSST survey across its distributed operations sites for the full ten year survey duration. To accomplish these complimentary goals and ensure that they result in self-consistent results, we have developed a holistic approach using the Sparx Enterprise Architect modeling tool and Systems Modeling Language (SysML). This approach utilizes SysML Use Cases, Actors, associated relationships, and Activity Diagrams to document and refine all of the major operations and maintenance activities that will be required to successfully operate the observatory and meet stakeholder expectations. We have developed several customized extensions of the SysML language including the creation of a custom stereotyped Use Case element with unique tagged values, as well as unique association connectors and Actor stereotypes. We demonstrate this customized MBSE methodology enables us to define: 1) the rolls each human Actor must take on to successfully carry out the activities associated with the Use Cases; 2) the skills each Actor must possess; 3) the functional allocation of all required stakeholder activities and Use Cases to organizational entities tasked with carrying them out; and 4) the organization structure required to successfully execute the operational survey. Our approach allows for continual refinement utilizing the systems engineering spiral method to expose finer levels of detail as necessary. For example, the bottom-up, Use Case-driven approach will be deployed in the future to develop the detailed work procedures required to successfully execute each operational activity.
Historical mathematical models, especially Great Lakes eutrophication models, traditionally used course segmentation schemes and relatively simple hydrodynamics to represent system behavior. Although many modelers have claimed success using such models, these representations can ...
Effects of distance from models on the fitness of floral mimics.
Duffy, K J; Johnson, S D
2017-05-01
Rewardless plants can attract pollinators by mimicking floral traits of rewarding heterospecific plants. This should result in the pollination success of floral mimics being dependent on the relative abundance of their models, as pollinator abundance and conditioning on model signals should be higher in the vicinity of the models. However, the attraction of pollinators to signals of the models may be partially innate, such that spatial isolation of mimics from model species may not strongly affect pollination success of mimics. We tested whether pollination rates and fruit set of the rewardless orchid Disa pulchra were influenced by proximity and abundance of its rewarding model species, Watsonia lepida. Pollination success of the orchid increased with proximity to the model species, while fruit set of the orchid increased with local abundance of the model species. Orchids that were experimentally translocated outside the model population experienced reduced pollinaria removal and increased pollinator-mediated self-pollination. These results confirm predictions that the pollination success of floral mimics should be dependent on the proximity and abundance of model taxa, and thus highlight the importance of ecological facilitation among species involved in mimicry systems. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.
Curtis, Evan T; Jamieson, Randall K
2018-04-01
Current theory has divided memory into multiple systems, resulting in a fractionated account of human behaviour. By an alternative perspective, memory is a single system. However, debate over the details of different single-system theories has overshadowed the converging agreement among them, slowing the reunification of memory. Evidence in favour of dividing memory often takes the form of dissociations observed in amnesia, where amnesic patients are impaired on some memory tasks but not others. The dissociations are taken as evidence for separate explicit and implicit memory systems. We argue against this perspective. We simulate two key dissociations between classification and recognition in a computational model of memory, A Theory of Nonanalytic Association. We assume that amnesia reflects a quantitative difference in the quality of encoding. We also present empirical evidence that replicates the dissociations in healthy participants, simulating amnesic behaviour by reducing study time. In both analyses, we successfully reproduce the dissociations. We integrate our computational and empirical successes with the success of alternative models and manipulations and argue that our demonstrations, taken in concert with similar demonstrations with similar models, provide converging evidence for a more general set of single-system analyses that support the conclusion that a wide variety of memory phenomena can be explained by a unified and coherent set of principles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dean, E. M.; Shin, Y. W.
1999-02-24
The Experimental Breeder Reactor II (EBR-II) at Argonne National Laboratory (ANL) West in Idaho is currently undergoing a plant closing operation, and a number of technical issues need to be addressed. This paper is related to the heat transfer analysis support effort performed for the upcoming draining operation of the primary sodium from the primary system tank. The issue addressed was how much of heat input would be required to the sodium if it were to be maintained in the liquid state during the prolonged period of the draining operation. The fluid dynamics analysis package FIDAP Code of Fluent Incorporatedmore » was used to model the primary tank system. It was possible to obtain solutions to the model in most of the cases considered, which provided the needed information for the project. However, certain appropriate choices of the solution algorithms were necessary in certain cases and in addition certain special measures had to be followed in order to successfully utilize the solution. In certain other instances, only some entirely different algorithm was the only successful choice, while in some other limited instances none of the algorithms or the special measures that were satisfactory for the earlier cases proved successful. Several configurations of the model with varying sodium levels to represent the quasi-steady state draining operation are considered. The reference configuration of the model was first calculated and the results are compared with measurement data. The model thus benchmarked to the reference case then was calculated for other model configurations. This paper discusses details of the experiences we gained, including successes, the difficulties we had to overcome, and in some instances the eventual failures. The results of the successful calculations are first presented. For each of the model configurations calculated, various computational aspects are then discussed in view of the numerical stability, convergence, and robustness of the solution algorithms in use. Finally, effects of certain model simplifications on the solutions and performance of the solution algorithms are discussed.« less
NASA Astrophysics Data System (ADS)
Umut Caglar, Mehmet; Pal, Ranadip
2010-10-01
The central dogma of molecular biology states that ``information cannot be transferred back from protein to either protein or nucleic acid.'' However, this assumption is not exactly correct in most of the cases. There are a lot of feedback loops and interactions between different levels of systems. These types of interactions are hard to analyze due to the lack of data in the cellular level and probabilistic nature of interactions. Probabilistic models like Stochastic Master Equation (SME) or deterministic models like differential equations (DE) can be used to analyze these types of interactions. SME models based on chemical master equation (CME) can provide detailed representation of genetic regulatory system, but their use is restricted by the large data requirements and computational costs of calculations. The differential equations models on the other hand, have low calculation costs and much more adequate to generate control procedures on the system; but they are not adequate to investigate the probabilistic nature of interactions. In this work the success of the mapping between SME and DE is analyzed, and the success of a control policy generated by DE model with respect to SME model is examined. Index Terms--- Stochastic Master Equation models, Differential Equation Models, Control Policy Design, Systems biology
A Categorical Framework for Model Classification in the Geosciences
NASA Astrophysics Data System (ADS)
Hauhs, Michael; Trancón y Widemann, Baltasar; Lange, Holger
2016-04-01
Models have a mixed record of success in the geosciences. In meteorology, model development and implementation has been among the first and most successful examples of triggering computer technology in science. On the other hand, notorious problems such as the 'equifinality issue' in hydrology lead to a rather mixed reputation of models in other areas. The most successful models in geosciences are applications of dynamic systems theory to non-living systems or phenomena. Thus, we start from the hypothesis that the success of model applications relates to the influence of life on the phenomenon under study. We thus focus on the (formal) representation of life in models. The aim is to investigate whether disappointment in model performance is due to system properties such as heterogeneity and historicity of ecosystems, or rather reflects an abstraction and formalisation problem at a fundamental level. As a formal framework for this investigation, we use category theory as applied in computer science to specify behaviour at an interface. Its methods have been developed for translating and comparing formal structures among different application areas and seems highly suited for a classification of the current "model zoo" in the geosciences. The approach is rather abstract, with a high degree of generality but a low level of expressibility. Here, category theory will be employed to check the consistency of assumptions about life in different models. It will be shown that it is sufficient to distinguish just four logical cases to check for consistency of model content. All four cases can be formalised as variants of coalgebra-algebra homomorphisms. It can be demonstrated that transitions between the four variants affect the relevant observations (time series or spatial maps), the formalisms used (equations, decision trees) and the test criteria of success (prediction, classification) of the resulting model types. We will present examples from hydrology and ecology in which a transport problem is combined with the strategic behaviour of living agents. The living and the non-living aspects of the model belong to two different model types. If a model is built to combine strategic behaviour with the constraint of mass conservation, some critical assumptions appear as inevitable, or models may become logically inconsistent. The categorical assessment and the examples demonstrate that many models at ecosystem level, where both living and non-living aspects inevitably meet, pose so far unsolved, fundamental problems. Today, these are often pragmatically resolved at the level of software engineering. Some suggestions will be given how model documentation and benchmarking may help clarifying and resolving some of these issues.
Stochastic models for regulatory networks of the genetic toggle switch.
Tian, Tianhai; Burrage, Kevin
2006-05-30
Bistability arises within a wide range of biological systems from the lambda phage switch in bacteria to cellular signal transduction pathways in mammalian cells. Changes in regulatory mechanisms may result in genetic switching in a bistable system. Recently, more and more experimental evidence in the form of bimodal population distributions indicates that noise plays a very important role in the switching of bistable systems. Although deterministic models have been used for studying the existence of bistability properties under various system conditions, these models cannot realize cell-to-cell fluctuations in genetic switching. However, there is a lag in the development of stochastic models for studying the impact of noise in bistable systems because of the lack of detailed knowledge of biochemical reactions, kinetic rates, and molecular numbers. In this work, we develop a previously undescribed general technique for developing quantitative stochastic models for large-scale genetic regulatory networks by introducing Poisson random variables into deterministic models described by ordinary differential equations. Two stochastic models have been proposed for the genetic toggle switch interfaced with either the SOS signaling pathway or a quorum-sensing signaling pathway, and we have successfully realized experimental results showing bimodal population distributions. Because the introduced stochastic models are based on widely used ordinary differential equation models, the success of this work suggests that this approach is a very promising one for studying noise in large-scale genetic regulatory networks.
Stochastic models for regulatory networks of the genetic toggle switch
Tian, Tianhai; Burrage, Kevin
2006-01-01
Bistability arises within a wide range of biological systems from the λ phage switch in bacteria to cellular signal transduction pathways in mammalian cells. Changes in regulatory mechanisms may result in genetic switching in a bistable system. Recently, more and more experimental evidence in the form of bimodal population distributions indicates that noise plays a very important role in the switching of bistable systems. Although deterministic models have been used for studying the existence of bistability properties under various system conditions, these models cannot realize cell-to-cell fluctuations in genetic switching. However, there is a lag in the development of stochastic models for studying the impact of noise in bistable systems because of the lack of detailed knowledge of biochemical reactions, kinetic rates, and molecular numbers. In this work, we develop a previously undescribed general technique for developing quantitative stochastic models for large-scale genetic regulatory networks by introducing Poisson random variables into deterministic models described by ordinary differential equations. Two stochastic models have been proposed for the genetic toggle switch interfaced with either the SOS signaling pathway or a quorum-sensing signaling pathway, and we have successfully realized experimental results showing bimodal population distributions. Because the introduced stochastic models are based on widely used ordinary differential equation models, the success of this work suggests that this approach is a very promising one for studying noise in large-scale genetic regulatory networks. PMID:16714385
A model for successful use of student response systems.
Klein, Kathleen; Kientz, Mary
2013-01-01
This article presents a model developed to assist teachers in selecting, implementing, and assessing student response system (SRS) use in the classroom. Research indicates that SRS technology is effective in achieving desired outcomes in higher education settings. Studies indicate that effective SRS use promotes greater achievement of learning outcomes, increased student attention, improved class participation, and active engagement. The model offered in this article is based on best practices described in the literature and several years of SRS use in a traditional higher education classroom setting. Student feedback indicates increased class participation and engagement with SRS technology. Teacher feedback indicates opportunities for contingent teaching. The model described in this article provides a process to assist teachers in the successful selection, implementation, and assessment of SRS technology in the classroom.
Monsoons: Processes, predictability, and the prospects for prediction
NASA Astrophysics Data System (ADS)
Webster, P. J.; Magaña, V. O.; Palmer, T. N.; Shukla, J.; Thomas, R. A.; Yanai, M.; Yasunari, T.
1998-06-01
The Tropical Ocean-Global Atmosphere (TOGA) program sought to determine the predictability of the coupled ocean-atmosphere system. The World Climate Research Programme's (WCRP) Global Ocean-Atmosphere-Land System (GOALS) program seeks to explore predictability of the global climate system through investigation of the major planetary heat sources and sinks, and interactions between them. The Asian-Australian monsoon system, which undergoes aperiodic and high amplitude variations on intraseasonal, annual, biennial and interannual timescales is a major focus of GOALS. Empirical seasonal forecasts of the monsoon have been made with moderate success for over 100 years. More recent modeling efforts have not been successful. Even simulation of the mean structure of the Asian monsoon has proven elusive and the observed ENSO-monsoon relationships has been difficult to replicate. Divergence in simulation skill occurs between integrations by different models or between members of ensembles of the same model. This degree of spread is surprising given the relative success of empirical forecast techniques. Two possible explanations are presented: difficulty in modeling the monsoon regions and nonlinear error growth due to regional hydrodynamical instabilities. It is argued that the reconciliation of these explanations is imperative for prediction of the monsoon to be improved. To this end, a thorough description of observed monsoon variability and the physical processes that are thought to be important is presented. Prospects of improving prediction and some strategies that may help achieve improvement are discussed.
NASA Astrophysics Data System (ADS)
Kempa, Wojciech M.
2017-12-01
A finite-capacity queueing system with server breakdowns is investigated, in which successive exponentially distributed failure-free times are followed by repair periods. After the processing a customer may either rejoin the queue (feedback) with probability q, or definitely leave the system with probability 1 - q. The system of integral equations for transient queue-size distribution, conditioned by the initial level of buffer saturation, is build. The solution of the corresponding system written for Laplace transforms is found using the linear algebraic approach. The considered queueing system can be successfully used in modelling production lines with machine failures, in which the parameter q may be considered as a typical fraction of items demanding corrections. Morever, this queueing model can be applied in the analysis of real TCP/IP performance, where q stands for the fraction of packets requiring retransmission.
Interventions in Early Mathematics: Avoiding Pollution and Dilution.
Sarama, Julie; Clements, Douglas H
2017-01-01
Although specific interventions in early mathematics have been successful, few have been brought to scale successfully, especially across the challenging diversity of populations and contexts in the early childhood system in the United States. In this chapter, we analyze a theoretically based scale-up model for early mathematics that was designed to avoid the pollution and dilution that often plagues efforts to achieve broad success. We elaborate the theoretical framework by noting the junctures that are susceptible to dilution or pollution. Then we expatiate the model's guidelines to describe specifically how they were designed and implemented to mitigate pollution and dilution. Finally, we provide evidence regarding the success of these efforts. © 2017 Elsevier Inc. All rights reserved.
Dong, Weizhen
2006-09-01
Each nation's government is searching for a cost-effective health care system. Some nations are developing their health care financing methods through gradual evolution of the existing ones, and others are trying to adopt other nations' successful schemes as their own financing strategies. The Singaporean government seems able to finance its nation's health care with a very low gross domestic product (GDP) input. Since the implementation of the medical savings accounts schemes (MSAs) in 1984, Singaporean government's share of the nation's total health care expenditure dropped from about 50% to 20%. Inspired by Singapore's success, the Chinese government adopted the Singaporean MSAs model as its health care financing schemes for urban areas. Shanghai was the first large urban centre to implement the MSAs in China. Through the study of the Singapore and Shanghai experiences, this article examines whether it is rational to borrow another nation's health care financing model, especially when the two societies have very different socioeconomic characteristics. However, the MSAs' success in Singapore did not guarantee its Shanghai success, because health care systems do not work alone. Through study of the MSAs' experiences in Singapore and Shanghai, this paper examines whether it is rational to borrow another nation's health care financing model, especially when the two societies have very different socioeconomic characteristics.
The Full Purpose Partnership Model for Promoting Academic and Socio-Emotional Success in Schools
ERIC Educational Resources Information Center
Anderson, Jeffrey A.; Houser, John H. W.; Howland, Allison
2010-01-01
In 2003, a partnership between a local system of care and a large urban school district led to the creation of a schoolwide educational model called the Full Purpose Partnership (FPP). This model was implemented in several elementary schools in Indianapolis, Indiana to integrate the principles of systems of care and wraparound with the techniques…
Using CASE to Exploit Process Modeling in Technology Transfer
NASA Technical Reports Server (NTRS)
Renz-Olar, Cheryl
2003-01-01
A successful business will be one that has processes in place to run that business. Creating processes, reengineering processes, and continually improving processes can be accomplished through extensive modeling. Casewise(R) Corporate Modeler(TM) CASE is a computer aided software engineering tool that will enable the Technology Transfer Department (TT) at NASA Marshall Space Flight Center (MSFC) to capture these abilities. After successful implementation of CASE, it could then go on to be applied in other departments at MSFC and other centers at NASA. The success of a business process is dependent upon the players working as a team and continuously improving the process. A good process fosters customer satisfaction as well as internal satisfaction in the organizational infrastructure. CASE provides a method for business process success through functions consisting of systems and processes business models; specialized diagrams; matrix management; simulation; report generation and publishing; and, linking, importing, and exporting documents and files. The software has an underlying repository or database to support these functions. The Casewise. manual informs us that dynamics modeling is a technique used in business design and analysis. Feedback is used as a tool for the end users and generates different ways of dealing with the process. Feedback on this project resulted from collection of issues through a systems analyst interface approach of interviews with process coordinators and Technical Points of Contact (TPOCs).
Tilahun, Binyam; Fritz, Fleur
2015-08-01
With the increasing implementation of Electronic Medical Record Systems (EMR) in developing countries, there is a growing need to identify antecedents of EMR success to measure and predict the level of adoption before costly implementation. However, less evidence is available about EMR success in the context of low-resource setting implementations. Therefore, this study aims to fill this gap by examining the constructs and relationships of the widely used DeLone and MacLean (D&M) information system success model to determine whether it can be applied to measure EMR success in those settings. A quantitative cross sectional study design using self-administered questionnaires was used to collect data from 384 health professionals working in five governmental hospitals in Ethiopia. The hospitals use a comprehensive EMR system since three years. Descriptive and structural equation modeling methods were applied to describe and validate the extent of relationship of constructs and mediating effects. The findings of the structural equation modeling shows that system quality has significant influence on EMR use (β = 0.32, P < 0.05) and user satisfaction (β = 0.53, P < 0.01); information quality has significant influence on EMR use (β = 0.44, P < 0.05) and user satisfaction (β = 0.48, P < 0.01) and service quality has strong significant influence on EMR use (β = 0.36, P < 0.05) and user satisfaction (β = 0.56, P < 0.01). User satisfaction has significant influence on EMR use (β = 0.41, P < 0.05) but the effect of EMR use on user satisfaction was not significant. Both EMR use and user satisfaction have significant influence on perceived net-benefit (β = 0.31, P < 0.01; β = 0.60, P < 0.01), respectively. Additionally, computer literacy was found to be a mediating factor in the relationship between service quality and EMR use (P < 0.05) as well as user satisfaction (P < 0.01). Among all the constructs, user satisfaction showed the strongest effect on perceived net-benefit of health professionals. EMR implementers and managers in developing countries are in urgent need of implementation models to design proper implementation strategies. In this study, the constructs and relationships depicted in the updated D&M model were found to be applicable to assess the success of EMR in low resource settings. Additionally, computer literacy was found to be a mediating factor in EMR use and user satisfaction of health professionals. Hence, EMR implementers and managers in those settings should give priority in improving service quality of the hospitals like technical support and infrastructure; providing continuous basic computer trainings to health professionals; and give attention to the system and information quality of the systems they want to implement.
Successful and unsuccessful psychopaths: a neurobiological model.
Gao, Yu; Raine, Adrian
2010-01-01
Despite increasing interest in psychopathy research, surprisingly little is known about the etiology of non-incarcerated, successful psychopaths. This review provides an analysis of current knowledge on the similarities and differences between successful and unsuccessful psychopaths derived from five population sources: community samples, individuals from employment agencies, college students, industrial psychopaths, and serial killers. An initial neurobiological model of successful and unsuccessful psychopathy is outlined. It is hypothesized that successful psychopaths have intact or enhanced neurobiological functioning that underlies their normal or even superior cognitive functioning, which in turn helps them to achieve their goals using more covert and nonviolent methods. In contrast, in unsuccessful, caught psychopaths, brain structural and functional impairments together with autonomic nervous system dysfunction are hypothesized to underlie cognitive and emotional deficits and more overt violent offending.
Dynamic contraction behaviour of pneumatic artificial muscle
NASA Astrophysics Data System (ADS)
Doumit, Marc D.; Pardoel, Scott
2017-07-01
The development of a dynamic model for the Pneumatic Artificial Muscle (PAM) is an imperative undertaking for understanding and analyzing the behaviour of the PAM as a function of time. This paper proposes a Newtonian based dynamic PAM model that includes the modeling of the muscle geometry, force, inertia, fluid dynamic, static and dynamic friction, heat transfer and valve flow while ignoring the effect of bladder elasticity. This modeling contribution allows the designer to predict, analyze and optimize PAM performance prior to its development. Thus advancing successful implementations of PAM based powered exoskeletons and medical systems. To date, most muscle dynamic properties are determined experimentally, furthermore, no analytical models that can accurately predict the muscle's dynamic behaviour are found in the literature. Most developed analytical models adequately predict the muscle force in static cases but neglect the behaviour of the system in the transient response. This could be attributed to the highly challenging task of deriving such a dynamic model given the number of system elements that need to be identified and the system's highly non-linear properties. The proposed dynamic model in this paper is successfully simulated through MATLAB programing and validated the pressure, contraction distance and muscle temperature with experimental testing that is conducted with in-house built prototype PAM's.
Pezzulo, Giovanni; Levin, Michael
2016-11-01
It is widely assumed in developmental biology and bioengineering that optimal understanding and control of complex living systems follows from models of molecular events. The success of reductionism has overshadowed attempts at top-down models and control policies in biological systems. However, other fields, including physics, engineering and neuroscience, have successfully used the explanations and models at higher levels of organization, including least-action principles in physics and control-theoretic models in computational neuroscience. Exploiting the dynamic regulation of pattern formation in embryogenesis and regeneration requires new approaches to understand how cells cooperate towards large-scale anatomical goal states. Here, we argue that top-down models of pattern homeostasis serve as proof of principle for extending the current paradigm beyond emergence and molecule-level rules. We define top-down control in a biological context, discuss the examples of how cognitive neuroscience and physics exploit these strategies, and illustrate areas in which they may offer significant advantages as complements to the mainstream paradigm. By targeting system controls at multiple levels of organization and demystifying goal-directed (cybernetic) processes, top-down strategies represent a roadmap for using the deep insights of other fields for transformative advances in regenerative medicine and systems bioengineering. © 2016 The Author(s).
2016-01-01
It is widely assumed in developmental biology and bioengineering that optimal understanding and control of complex living systems follows from models of molecular events. The success of reductionism has overshadowed attempts at top-down models and control policies in biological systems. However, other fields, including physics, engineering and neuroscience, have successfully used the explanations and models at higher levels of organization, including least-action principles in physics and control-theoretic models in computational neuroscience. Exploiting the dynamic regulation of pattern formation in embryogenesis and regeneration requires new approaches to understand how cells cooperate towards large-scale anatomical goal states. Here, we argue that top-down models of pattern homeostasis serve as proof of principle for extending the current paradigm beyond emergence and molecule-level rules. We define top-down control in a biological context, discuss the examples of how cognitive neuroscience and physics exploit these strategies, and illustrate areas in which they may offer significant advantages as complements to the mainstream paradigm. By targeting system controls at multiple levels of organization and demystifying goal-directed (cybernetic) processes, top-down strategies represent a roadmap for using the deep insights of other fields for transformative advances in regenerative medicine and systems bioengineering. PMID:27807271
Redefining success as significance through leadership in the new economy.
De Jong, Steven A
2006-03-01
This review re-examines our current definition of success in the current economic system and challenges the surgeon to play a significant part in role modeling and mentoring surgical residents and other healthcare professionals. Leadership skills are presented and implementation strategies are suggested.
[The dangers and drifts of health McDonaldization].
Cembrani, Fabio
2016-01-01
The author reflects on the healthcare crisis, starting from globalization and liquid-modern society, with its systemic contradictions. The health care system is influenced by McDonald's success and its philosophy: efficiency, productivity, cost reduction, procedural standardization and control. This article underlines the deficiencies and manipulations in the health care system. The profit-oriented economic model is successful due to lack of attention to product quality from the globalised and hyper-consumerist society. Italian legislation has regulated the standardization in healthcare procedure, aiming at cost reduction of defensive medicine. It has been underlined that it defines actions, nevertheless human activity is mainly realized through language, gesture and creation. A new anthropological model is proposed, based on commitment and distributive justice.
ERIC Educational Resources Information Center
Hew, Khe Foon
2009-01-01
Recent empirical evidence suggests that the updated DeLone and McLean's information systems (D&M IS) model can identify the determinants of success of online communities in terms of member loyalty (Lin and Lee 2006). This study is similarly concerned with the challenge of identifying the determinants of success of online communities, but it…
ERIC Educational Resources Information Center
Tran, Kiet T.
2012-01-01
This study examined the relationship between information technology (IT) governance and software reuse success. Software reuse has been mostly an IT problem but rarely a business one. Studies in software reuse are abundant; however, to date, none has a deep appreciation of IT governance. This study demonstrated that IT governance had a positive…
The global increase of noxious bloom occurrences has increased the need for phytoplankton management schemes. Such schemes require the ability to predict phytoplankton succession. Equilibrium Resources Competition theory, which is popular for predicting succession in lake systems...
Human Systems Engineering: A Learning Model Designed To Converge Education, Business, and Industry.
ERIC Educational Resources Information Center
Hanson, Karen L.
The Human Systems Engineering (HSE) Model was created to facilitate collaboration among education, business, and industry. It emphasized the role of leaders who converge with others to accomplish their goals while paying attention to the key elements that create successful partnerships. The partnership of XXsys Technologies, Inc., University of…
Methods for integrated modeling of landscape change: Interior Northwest Landscape Analysis System.
Jane L. Hayes; Alan. A. Ager; R. James Barbour
2004-01-01
The Interior Northwest Landscape Analysis System (INLAS) links a number of resource, disturbance, and landscape simulations models to examine the interactions of vegetative succession, management, and disturbance with policy goals. The effects of natural disturbance like wildfire, herbivory, forest insects and diseases, as well as specific management actions are...
Human Behavior Based Exploratory Model for Successful Implementation of Lean Enterprise in Industry
ERIC Educational Resources Information Center
Sawhney, Rupy; Chason, Stewart
2005-01-01
Currently available Lean tools such as Lean Assessments, Value Stream Mapping, and Process Flow Charting focus on system requirements and overlook human behavior. A need is felt for a tool that allows one to baseline personnel, determine personnel requirements and align system requirements with personnel requirements. Our exploratory model--The…
Technique Selectively Represses Immune System
... from attacking myelin in a mouse model of multiple sclerosis. Dr David Furness, Wellcome Images. All rights reserved ... devised a way to successfully treat symptoms resembling multiple sclerosis in a mouse model. With further development, the ...
Using A Model-Based Systems Engineering Approach For Exploration Medical System Development
NASA Technical Reports Server (NTRS)
Hanson, A.; Mindock, J.; McGuire, K.; Reilly, J.; Cerro, J.; Othon, W.; Rubin, D.; Urbina, M.; Canga, M.
2017-01-01
NASA's Human Research Program's Exploration Medical Capabilities (ExMC) element is defining the medical system needs for exploration class missions. ExMC's Systems Engineering (SE) team will play a critical role in successful design and implementation of the medical system into exploration vehicles. The team's mission is to "Define, develop, validate, and manage the technical system design needed to implement exploration medical capabilities for Mars and test the design in a progression of proving grounds." Development of the medical system is being conducted in parallel with exploration mission architecture and vehicle design development. Successful implementation of the medical system in this environment will require a robust systems engineering approach to enable technical communication across communities to create a common mental model of the emergent engineering and medical systems. Model-Based Systems Engineering (MBSE) improves shared understanding of system needs and constraints between stakeholders and offers a common language for analysis. The ExMC SE team is using MBSE techniques to define operational needs, decompose requirements and architecture, and identify medical capabilities needed to support human exploration. Systems Modeling Language (SysML) is the specific language the SE team is utilizing, within an MBSE approach, to model the medical system functional needs, requirements, and architecture. Modeling methods are being developed through the practice of MBSE within the team, and tools are being selected to support meta-data exchange as integration points to other system models are identified. Use of MBSE is supporting the development of relationships across disciplines and NASA Centers to build trust and enable teamwork, enhance visibility of team goals, foster a culture of unbiased learning and serving, and be responsive to customer needs. The MBSE approach to medical system design offers a paradigm shift toward greater integration between vehicle and the medical system and directly supports the transition of Earth-reliant ISS operations to the Earth-independent operations envisioned for Mars. Here, we describe the methods and approach to building this integrated model.
Ordinary Differential Equation Models for Adoptive Immunotherapy.
Talkington, Anne; Dantoin, Claudia; Durrett, Rick
2018-05-01
Modified T cells that have been engineered to recognize the CD19 surface marker have recently been shown to be very successful at treating acute lymphocytic leukemias. Here, we explore four previous approaches that have used ordinary differential equations to model this type of therapy, compare their properties, and modify the models to address their deficiencies. Although the four models treat the workings of the immune system in slightly different ways, they all predict that adoptive immunotherapy can be successful to move a patient from the large tumor fixed point to an equilibrium with little or no tumor.
NASA Technical Reports Server (NTRS)
He, Yuning
2015-01-01
Safety of unmanned aerial systems (UAS) is paramount, but the large number of dynamically changing controller parameters makes it hard to determine if the system is currently stable, and the time before loss of control if not. We propose a hierarchical statistical model using Treed Gaussian Processes to predict (i) whether a flight will be stable (success) or become unstable (failure), (ii) the time-to-failure if unstable, and (iii) time series outputs for flight variables. We first classify the current flight input into success or failure types, and then use separate models for each class to predict the time-to-failure and time series outputs. As different inputs may cause failures at different times, we have to model variable length output curves. We use a basis representation for curves and learn the mappings from input to basis coefficients. We demonstrate the effectiveness of our prediction methods on a NASA neuro-adaptive flight control system.
An object-oriented, technology-adaptive information model
NASA Technical Reports Server (NTRS)
Anyiwo, Joshua C.
1995-01-01
The primary objective was to develop a computer information system for effectively presenting NASA's technologies to American industries, for appropriate commercialization. To this end a comprehensive information management model, applicable to a wide variety of situations, and immune to computer software/hardware technological gyrations, was developed. The model consists of four main elements: a DATA_STORE, a data PRODUCER/UPDATER_CLIENT and a data PRESENTATION_CLIENT, anchored to a central object-oriented SERVER engine. This server engine facilitates exchanges among the other model elements and safeguards the integrity of the DATA_STORE element. It is designed to support new technologies, as they become available, such as Object Linking and Embedding (OLE), on-demand audio-video data streaming with compression (such as is required for video conferencing), Worldwide Web (WWW) and other information services and browsing, fax-back data requests, presentation of information on CD-ROM, and regular in-house database management, regardless of the data model in place. The four components of this information model interact through a system of intelligent message agents which are customized to specific information exchange needs. This model is at the leading edge of modern information management models. It is independent of technological changes and can be implemented in a variety of ways to meet the specific needs of any communications situation. This summer a partial implementation of the model has been achieved. The structure of the DATA_STORE has been fully specified and successfully tested using Microsoft's FoxPro 2.6 database management system. Data PRODUCER/UPDATER and PRESENTATION architectures have been developed and also successfully implemented in FoxPro; and work has started on a full implementation of the SERVER engine. The model has also been successfully applied to a CD-ROM presentation of NASA's technologies in support of Langley Research Center's TAG efforts.
Ma, Pei-Luen; Jheng, Yan-Wun; Jheng, Bi-Wei; Hou, I-Ching
2017-01-01
Bar code medication administration (BCMA) could reduce medical errors and promote patient safety. This research uses modified information systems success model (M-ISS model) to evaluate nurses' acceptance to BCMA. The result showed moderate correlation between medication administration safety (MAS) to system quality, information quality, service quality, user satisfaction, and limited satisfaction.
Noyes, Jane; Brenner, Maria; Fox, Patricia; Guerin, Ashleigh
2014-05-01
To report a novel review to develop a health systems model of successful transition of children with complex healthcare needs from hospital to home. Children with complex healthcare needs commonly experience an expensive, ineffectual and prolonged nurse-led discharge process. Children gain no benefit from prolonged hospitalization and are exposed to significant harm. Research to enable intervention development and process evaluation across the entire health system is lacking. Novel mixed-method integrative review informed by health systems theory. DATA CINAHL, PsychInfo, EMBASE, PubMed, citation searching, personal contact. REVIEW Informed by consultation with experts. English language studies, opinion/discussion papers reporting research, best practice and experiences of children, parents and healthcare professionals and purposively selected policies/guidelines from 2002-December 2012 were abstracted using Framework synthesis, followed by iterative theory development. Seven critical factors derived from thirty-four sources across five health system levels explained successful discharge (new programme theory). All seven factors are required in an integrated care pathway, with a dynamic communication loop to facilitate effective discharge (new programme logic). Current health system responses were frequently static and critical success factors were commonly absent, thereby explaining ineffectual discharge. The novel evidence-based model, which reconceptualizes 'discharge' as a highly complex longitudinal health system intervention, makes a significant contribution to global knowledge to drive practice development. Research is required to develop process and outcome measures at different time points in the discharge process and future trials are needed to determine the effectiveness of integrated health system discharge models. © 2013 John Wiley & Sons Ltd.
The changing paradigm in surgery is system integration: How do we respond?
Zenilman, Michael E; Freischlag, Julie-Ann
2017-12-08
With expansion of health care systems across the country, close relationships need to be developed between academic medical centers and their affiliated community hospitals. This creates opportunity to integrate surgical programs across different hospitals. Herein we describe a model of surgical integration at the system level of five large hospitals. We discuss utilizing advantages that both the academic and community hospital bring to the model. A close relationship between an interdisciplinary team, which includes the academic surgical chair, a regional director liaison who was embedded in the community, individual hospital leadership, and practice plan leaders was created. Three pillars as a foundation to success were physician leadership, the use of system infrastructure and development of new processes. This resulted in development of trust, leading to successful recruitments, models of employment and expansion into novel areas of patient safety. Once created, new opportunities for programming for surgical safety across the health care were identified. Copyright © 2017 Elsevier Inc. All rights reserved.
A model of systems integration to facilitate ITS deployment : FAST-TRAC phase IV deliverable
DOT National Transportation Integrated Search
2003-04-01
The FAST-TRAC (Faster and Safer Travel through Traffic Routing and Advanced Controls) Intelligent Transportation Systems (ITS) Field Test in Oakland County, an urbanized county in metropolitan Detroit, represents a large and successful systems integr...
Maron, Jill L.; Hwang, Jooyeon S.; Pathak, Subash; Ruthazer, Robin; Russell, Ruby L.; Alterovitz, Gil
2014-01-01
Objective To combine mathematical modeling of salivary gene expression microarray data and systems biology annotation with RT-qPCR amplification to identify (phase I) and validate (phase II) salivary biomarker analysis for the prediction of oral feeding readiness in preterm infants. Study design Comparative whole transcriptome microarray analysis from 12 preterm newborns pre- and post-oral feeding success was used for computational modeling and systems biology analysis to identify potential salivary transcripts associated with oral feeding success (phase I). Selected gene expression biomarkers (15 from computational modeling; 6 evidence-based; and 3 reference) were evaluated by RT-qPCR amplification on 400 salivary samples from successful (n=200) and unsuccessful (n=200) oral feeders (phase II). Genes, alone and in combination, were evaluated by a multivariate analysis controlling for sex and post-conceptional age (PCA) to determine the probability that newborns achieved successful oral feeding. Results Advancing post-conceptional age (p < 0.001) and female sex (p = 0.05) positively predicted an infant’s ability to feed orally. A combination of five genes, NPY2R (hunger signaling), AMPK (energy homeostasis), PLXNA1 (olfactory neurogenesis), NPHP4 (visual behavior) and WNT3 (facial development), in addition to PCA and sex, demonstrated good accuracy for determining feeding success (AUROC = 0.78). Conclusions We have identified objective and biologically relevant salivary biomarkers that noninvasively assess a newborn’s developing brain, sensory and facial development as they relate to oral feeding success. Understanding the mechanisms that underlie the development of oral feeding readiness through translational and computational methods may improve clinical decision making while decreasing morbidities and health care costs. PMID:25620512
Crookes, D J; Blignaut, J N; de Wit, M P; Esler, K J; Le Maitre, D C; Milton, S J; Mitchell, S A; Cloete, J; de Abreu, P; Fourie nee Vlok, H; Gull, K; Marx, D; Mugido, W; Ndhlovu, T; Nowell, M; Pauw, M; Rebelo, A
2013-05-15
Can markets assist by providing support for ecological restoration, and if so, under what conditions? The first step in addressing this question is to develop a consistent methodology for economic evaluation of ecological restoration projects. A risk analysis process was followed in which a system dynamics model was constructed for eight diverse case study sites where ecological restoration is currently being pursued. Restoration costs vary across each of these sites, as do the benefits associated with restored ecosystem functioning. The system dynamics model simulates the ecological, hydrological and economic benefits of ecological restoration and informs a portfolio mapping exercise where payoffs are matched against the likelihood of success of a project, as well as a number of other factors (such as project costs and risk measures). This is the first known application that couples ecological restoration with system dynamics and portfolio mapping. The results suggest an approach that is able to move beyond traditional indicators of project success, since the effect of discounting is virtually eliminated. We conclude that systems dynamic modelling with portfolio mapping can guide decisions on when markets for restoration activities may be feasible. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Ramantoko, Gadang; Irawan, Herry
2017-10-01
This research examines the factors influencing the Information Sharing Model in Supporting Implementation of e-Procurement Services: Case of Bandung City in its early maturity stage. The early maturity of information sharing stage was determined using e-Government Maturity Stage Conceptual Framework from Estevez. Bandung City e-Procurement Information Sharing system was categorized at stage 1 in Estevez' model where the concern was mainly on assessing the benefit and risk of implementing the system. The Authors were using DeLone & McLean (D&M) Information System Success model to study benefit and risk of implementing the system in Bandung city. The model was then empirically tested by employing survey data that was collected from the available 40 listed supplier firms. D&M's model adjusted by Klischewski's description was introducing Information Quality, System Quality, and Service Quality as independent variable; Usability and User Satisfaction as intermediate dependent variable; and Perceived Net Benefit as final dependent variable. The findings suggested that, all of the predictors in D&M's model significantly influenced the net perceived benefit of implementing the e-Procurement system in the early maturity stage. The theoretical contribution of this research suggested that D&M's model might find useful in modeling complex information technology successfulness such as the one used in e-Procurement service. This research could also have implications for policy makers (LPSE) and system providers (LKPP) following the introduction of the service. However, the small number of respondent might be considered limitation of the study. The model needs to be further tested using larger number of respondents by involving the population of the firms in extended boundary/municipality area around Bandung.
Active Tensor Magnetic Gradiometer System
2007-11-01
Modify Forward Computer Models .............................................................................................2 Modify TMGS Simulator...active magnetic gradient measurement system are based upon the existing tensor magnetic gradiometer system ( TMGS ) developed under project MM-1328...Magnetic Gradiometer System ( TMGS ) for UXO Detection, Imaging, and Discrimination.” The TMGS developed under MM-1328 was successfully tested at the
Next-Term Student Performance Prediction: A Recommender Systems Approach
ERIC Educational Resources Information Center
Sweeney, Mack; Rangwala, Huzefa; Lester, Jaime; Johri, Aditya
2016-01-01
An enduring issue in higher education is student retention to successful graduation. National statistics indicate that most higher education institutions have four-year degree completion rates around 50%, or just half of their student populations. While there are prediction models which illuminate what factors assist with college student success,…
Spectral Bayesian Knowledge Tracing
ERIC Educational Resources Information Center
Falakmasir, Mohammad; Yudelson, Michael; Ritter, Steve; Koedinger, Ken
2015-01-01
Bayesian Knowledge Tracing (BKT) has been in wide use for modeling student skill acquisition in Intelligent Tutoring Systems (ITS). BKT tracks and updates student's latent mastery of a skill as a probability distribution of a binary variable. BKT does so by accounting for observed student successes in applying the skill correctly, where success is…
A System's View of E-Learning Success Model
ERIC Educational Resources Information Center
Eom, Sean B.; Ashill, Nicholas J.
2018-01-01
The past several decades of e-learning empirical research have advanced our understanding of the effective management of critical success factors (CSFs) of e-learning. Meanwhile, the proliferation of measures of dependent and independent variables has been overelaborated. We argue that a significant reduction in dependent and independent variables…
Japanese and United States Schooling: A Comparative Perspective.
ERIC Educational Resources Information Center
Shields, James J.
Scholars and educational policymakers are interested in identifying successful national school systems that might provide effective models of educational theory and practice for transfer to other nations. U.S. educators have been interested in the success Japan has had in a broad range of measures of academic achievement and school participation…
Improved numerical solutions for chaotic-cancer-model
NASA Astrophysics Data System (ADS)
Yasir, Muhammad; Ahmad, Salman; Ahmed, Faizan; Aqeel, Muhammad; Akbar, Muhammad Zubair
2017-01-01
In biological sciences, dynamical system of cancer model is well known due to its sensitivity and chaoticity. Present work provides detailed computational study of cancer model by counterbalancing its sensitive dependency on initial conditions and parameter values. Cancer chaotic model is discretized into a system of nonlinear equations that are solved using the well-known Successive-Over-Relaxation (SOR) method with a proven convergence. This technique enables to solve large systems and provides more accurate approximation which is illustrated through tables, time history maps and phase portraits with detailed analysis.
Technology Investments in the NASA Entry Systems Modeling Project
NASA Technical Reports Server (NTRS)
Barnhardt, Michael; Wright, Michael; Hughes, Monica
2017-01-01
The Entry Systems Modeling (ESM) technology development project, initiated in 2012 under NASAs Game Changing Development (GCD) Program, is engaged in maturation of fundamental research developing aerosciences, materials, and integrated systems products for entry, descent, and landing(EDL)technologies [1]. To date, the ESM project has published over 200 papers in these areas, comprising the bulk of NASAs research program for EDL modeling. This presentation will provide an overview of the projects successes and challenges, and an assessment of future investments in EDL modeling and simulation relevant to NASAs mission
Molecular simulations of self-assembly processes in metal-organic frameworks: Model dependence
NASA Astrophysics Data System (ADS)
Biswal, Debasmita; Kusalik, Peter G.
2017-07-01
Molecular simulation is a powerful tool for investigating microscopic behavior in various chemical systems, where the use of suitable models is critical to successfully reproduce the structural and dynamic properties of the real systems of interest. In this context, molecular dynamics simulation studies of self-assembly processes in metal-organic frameworks (MOFs), a well-known class of porous materials with interesting chemical and physical properties, are relatively challenging, where a reasonably accurate representation of metal-ligand interactions is anticipated to play an important role. In the current study, we both investigate the performance of some existing models and introduce and test new models to help explore the self-assembly in an archetypal Zn-carboxylate MOF system. To this end, the behavior of six different Zn-ion models, three solvent models, and two ligand models was examined and validated against key experimental structural parameters. To explore longer time scale ordering events during MOF self-assembly via explicit solvent simulations, it is necessary to identify a suitable combination of simplified model components representing metal ions, organic ligands, and solvent molecules. It was observed that an extended cationic dummy atom (ECDA) Zn-ion model combined with an all-atom carboxylate ligand model and a simple dipolar solvent model can reproduce characteristic experimental structures for the archetypal MOF system. The successful use of these models in extensive sets of molecular simulations, which provide key insights into the self-assembly mechanism of this archetypal MOF system occurring during the early stages of this process, has been very recently reported.
Optimal Mission Abort Policy for Systems Operating in a Random Environment.
Levitin, Gregory; Finkelstein, Maxim
2018-04-01
Many real-world critical systems, e.g., aircrafts, manned space flight systems, and submarines, utilize mission aborts to enhance their survivability. Specifically, a mission can be aborted when a certain malfunction condition is met and a rescue or recovery procedure is then initiated. For systems exposed to external impacts, the malfunctions are often caused by the consequences of these impacts. Traditional system reliability models typically cannot address a possibility of mission aborts. Therefore, in this article, we first develop the corresponding methodology for modeling and evaluation of the mission success probability and survivability of systems experiencing both internal failures and external shocks. We consider a policy when a mission is aborted and a rescue procedure is activated upon occurrence of the mth shock. We demonstrate the tradeoff between the system survivability and the mission success probability that should be balanced by the proper choice of the decision variable m. A detailed illustrative example of a mission performed by an unmanned aerial vehicle is presented. © 2017 Society for Risk Analysis.
Smart Stylet: The development and use of a bedside external ventricular drain image-guidance system
Patil, Vaibhav; Gupta, Rajiv; Estépar, Raúl San José; Lacson, Ronilda; Cheung, Arnold; Wong, Judith M.; Popp, A. John; Golby, Alexandra; Ogilvy, Christopher; Vosburgh, Kirby G.
2015-01-01
Background Placement accuracy of ventriculostomy catheters is reported in a wide and variable range. Development of an efficient image-guidance system may improve physician performance and patient safety. Objective We evaluate the prototype of Smart Stylet, a new electromagnetic image-guidance system for use during bedside ventriculostomy. Methods Accuracy of the Smart Stylet system was assessed. System operators were evaluated for their ability to successfully target the ipsilateral frontal horn in a phantom model. Results Target registration error across 15 intracranial targets ranged from 1.3 – 4.6 mm (mean 3.1 mm). Using Smart Stylet guidance, a test operator successfully passed a ventriculostomy catheter to a shifted ipsilateral frontal horn 20/20 (100%) times from the frontal approach in a skull phantom. Without Smart Stylet guidance, the operator was successful 4/10 (40 %) from the right frontal approach and 6/10 (60 %) from the left frontal approach. In a separate experiment, resident operators were successful 2/4 (50%) when targeting the shifted ipsilateral frontal horn with Smart Stylet guidance and 0/4 (0 %) without image-guidance using a skull phantom. Conclusions Smart Stylet may improve the ability to successfully target the ventricles during frontal ventriculostomy. PMID:25662506
Software Prototyping: Designing Systems for Users.
ERIC Educational Resources Information Center
Spies, Phyllis Bova
1983-01-01
Reports on major change in computer software development process--the prototype model, i.e., implementation of skeletal system that is enhanced during interaction with users. Expensive and unreliable software, software design errors, traditional development approach, resources required for prototyping, success stories, and systems designer's role…
NASA Astrophysics Data System (ADS)
Destyanto, A. R.; Silalahi, T. D.; Hidayatno, A.
2017-11-01
System dynamic modeling is widely used to predict and simulate the energy system in several countries. One of the applications of system dynamics is to evaluate national energy policy alternatives, and energy efficiency analysis. Using system dynamic modeling, this research aims to evaluate the energy transition policy that has been implemented in Indonesia on the past conversion program of kerosene to LPG for household cook fuel consumption, which considered as successful energy transition program implemented since 2007. This research is important since Indonesia considered not yet succeeded to execute another energy transition program on conversion program of oil fuel to gas fuel for transportation that has started since 1989. The aim of this research is to explore which policy intervention that has significant contribution to support or even block the conversion program. Findings in this simulation show that policy intervention to withdraw the kerosene supply and government push to increase production capacity of the support equipment industries (gas stove, regulator, and LPG Cylinder) is the main influence on the success of the program conversion program.
Successful approaches to deploying a Metropolitan Intelligent Transportation System.
DOT National Transportation Integrated Search
1999-03-01
To identify and evaluate the institutional structures and working relationships associated with the deployment and integration of Intelligent Transportation Systems (ITS) products and services at the Model Deployment Initiatives (MDIs), the Volpe Cen...
Requirements based system level risk modeling
NASA Technical Reports Server (NTRS)
Meshkat, Leila; Cornford, Steven; Feather, Martin
2004-01-01
The problem that we address in this paper is assessing the expected degree of success of the system or mission based on the degree to which each requirement is satisfied and the relative weight of the requirements.
Optical Elastography of Systemic Sclerosis Skin
2017-09-01
1, the animal model of SSc has been successfully re-established. In addition, animals are being scheduled for the proposed treatment and monitoring...study. 15. SUBJECT TERMS Systemic Sclerosis, Imaging, Skin, Diagnostics, Animal Models, OCT, OCE 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...Diagnostics, Animal Models, OCT, OCE 3.ACCOMPLISHMENTS: o What were the major goals of the project? The goals of Aim 1, as outlined in the SOW were
A Framework to Manage Information Models
NASA Astrophysics Data System (ADS)
Hughes, J. S.; King, T.; Crichton, D.; Walker, R.; Roberts, A.; Thieman, J.
2008-05-01
The Information Model is the foundation on which an Information System is built. It defines the entities to be processed, their attributes, and the relationships that add meaning. The development and subsequent management of the Information Model is the single most significant factor for the development of a successful information system. A framework of tools has been developed that supports the management of an information model with the rigor typically afforded to software development. This framework provides for evolutionary and collaborative development independent of system implementation choices. Once captured, the modeling information can be exported to common languages for the generation of documentation, application databases, and software code that supports both traditional and semantic web applications. This framework is being successfully used for several science information modeling projects including those for the Planetary Data System (PDS), the International Planetary Data Alliance (IPDA), the National Cancer Institute's Early Detection Research Network (EDRN), and several Consultative Committee for Space Data Systems (CCSDS) projects. The objective of the Space Physics Archive Search and Exchange (SPASE) program is to promote collaboration and coordination of archiving activity for the Space Plasma Physics community and ensure the compatibility of the architectures used for a global distributed system and the individual data centers. Over the past several years, the SPASE data model working group has made great progress in developing the SPASE Data Model and supporting artifacts including a data dictionary, XML Schema, and two ontologies. The authors have captured the SPASE Information Model in this framework. This allows the generation of documentation that presents the SPASE Information Model in object-oriented notation including UML class diagrams and class hierarchies. The modeling information can also be exported to semantic web languages such as OWL and RDF and written to XML Metadata Interchange (XMI) files for import into UML tools.
Land Surface Microwave Emissivity Dynamics: Observations, Analysis and Modeling
NASA Technical Reports Server (NTRS)
Tian, Yudong; Peters-Lidard, Christa D.; Harrison, Kenneth W.; Kumar, Sujay; Ringerud, Sarah
2014-01-01
Land surface microwave emissivity affects remote sensing of both the atmosphere and the land surface. The dynamical behavior of microwave emissivity over a very diverse sample of land surface types is studied. With seven years of satellite measurements from AMSR-E, we identified various dynamical regimes of the land surface emission. In addition, we used two radiative transfer models (RTMs), the Community Radiative Transfer Model (CRTM) and the Community Microwave Emission Modeling Platform (CMEM), to simulate land surface emissivity dynamics. With both CRTM and CMEM coupled to NASA's Land Information System, global-scale land surface microwave emissivities were simulated for five years, and evaluated against AMSR-E observations. It is found that both models have successes and failures over various types of land surfaces. Among them, the desert shows the most consistent underestimates (by approx. 70-80%), due to limitations of the physical models used, and requires a revision in both systems. Other snow-free surface types exhibit various degrees of success and it is expected that parameter tuning can improve their performances.
Use of statecharts in the modelling of dynamic behaviour in the ATLAS DAQ prototype-1
NASA Astrophysics Data System (ADS)
Croll, P.; Duval, P.-Y.; Jones, R.; Kolos, S.; Sari, R. F.; Wheeler, S.
1998-08-01
Many applications within the ATLAS DAQ prototype-1 system have complicated dynamic behaviour which can be successfully modelled in terms of states and transitions between states. Previously, state diagrams implemented as finite-state machines have been used. Although effective, they become ungainly as system size increases. Harel statecharts address this problem by implementing additional features such as hierarchy and concurrency. The CHSM object-oriented language system is freeware which implements Harel statecharts as concurrent, hierarchical, finite-state machines (CHSMs). An evaluation of this language system by the ATLAS DAQ group has shown it to be suitable for describing the dynamic behaviour of typical DAQ applications. The language is currently being used to model the dynamic behaviour of the prototype-1 run-control system. The design is specified by means of a CHSM description file, and C++ code is obtained by running the CHSM compiler on the file. In parallel with the modelling work, a code generator has been developed which translates statecharts, drawn using the StP CASE tool, into the CHSM language. C++ code, describing the dynamic behaviour of the run-control system, has been successfully generated directly from StP statecharts using the CHSM generator and compiler. The validity of the design was tested using the simulation features of the Statemate CASE tool.
Integration agent-based models and GIS as a virtual urban dynamic laboratory
NASA Astrophysics Data System (ADS)
Chen, Peng; Liu, Miaolong
2007-06-01
Based on the Agent-based Model and spatial data model, a tight-coupling integrating method of GIS and Agent-based Model (ABM) is to be discussed in this paper. The use of object-orientation for both spatial data and spatial process models facilitates their integration, which can allow exploration and explanation of spatial-temporal phenomena such as urban dynamic. In order to better understand how tight coupling might proceed and to evaluate the possible functional and efficiency gains from such a tight coupling, the agent-based model and spatial data model are discussed, and then the relationships affecting spatial data model and agent-based process models interaction. After that, a realistic crowd flow simulation experiment is presented. Using some tools provided by general GIS systems and a few specific programming languages, a new software system integrating GIS and MAS as a virtual laboratory applicable for simulating pedestrian flows in a crowd activity centre has been developed successfully. Under the environment supported by the software system, as an applicable case, a dynamic evolution process of the pedestrian's flows (dispersed process for the spectators) in a crowds' activity center - The Shanghai Stadium has been simulated successfully. At the end of the paper, some new research problems have been pointed out for the future.
GEM System: automatic prototyping of cell-wide metabolic pathway models from genomes.
Arakawa, Kazuharu; Yamada, Yohei; Shinoda, Kosaku; Nakayama, Yoichi; Tomita, Masaru
2006-03-23
Successful realization of a "systems biology" approach to analyzing cells is a grand challenge for our understanding of life. However, current modeling approaches to cell simulation are labor-intensive, manual affairs, and therefore constitute a major bottleneck in the evolution of computational cell biology. We developed the Genome-based Modeling (GEM) System for the purpose of automatically prototyping simulation models of cell-wide metabolic pathways from genome sequences and other public biological information. Models generated by the GEM System include an entire Escherichia coli metabolism model comprising 968 reactions of 1195 metabolites, achieving 100% coverage when compared with the KEGG database, 92.38% with the EcoCyc database, and 95.06% with iJR904 genome-scale model. The GEM System prototypes qualitative models to reduce the labor-intensive tasks required for systems biology research. Models of over 90 bacterial genomes are available at our web site.
Market Assessment of Forward-Looking Turbulence Sensing Systems
NASA Technical Reports Server (NTRS)
Kauffmann, Paul
2003-01-01
This viewgraph presentation provides a cost benefit analysis of three next-generation forward-looking turbulence sensing systems: X band turbulence radar system for convective turbulence, LIDAR based turbulence systems to sense clear air turbulence and a combined hybrid system. Parameters for the cost benefit analysis were established using a business model which considered injury rates, cost of injuries, indirect costs, market penetration rate estimates and product success characteristics. Topics covered include: study approach, business case equations, data acquisition, benchmark analysis. Data interpretation from the cost benefit analysis is presented. The researchers conclude that the market potential for these products is based primarily on injury cost reduction and that X band radar systems have the greatest chance for commercial success.
NASA Technical Reports Server (NTRS)
James, G. H.; Imbrie, P. K.; Hill, P. S.; Allen, D. H.; Haisler, W. E.
1988-01-01
Four current viscoplastic models are compared experimentally for Inconel 718 at 593 C. This material system responds with apparent negative strain rate sensitivity, undergoes cyclic work softening, and is susceptible to low cycle fatigue. A series of tests were performed to create a data base from which to evaluate material constants. A method to evaluate the constants is developed which draws on common assumptions for this type of material, recent advances by other researchers, and iterative techniques. A complex history test, not used in calculating the constants, is then used to compare the predictive capabilities of the models. The combination of exponentially based inelastic strain rate equations and dynamic recovery is shown to model this material system with the greatest success. The method of constant calculation developed was successfully applied to the complex material response encountered. Backstress measuring tests were found to be invaluable and to warrant further development.
A new data assimilation engine for physics-based thermospheric density models
NASA Astrophysics Data System (ADS)
Sutton, E. K.; Henney, C. J.; Hock-Mysliwiec, R.
2017-12-01
The successful assimilation of data into physics-based coupled Ionosphere-Thermosphere models requires rethinking the filtering techniques currently employed in fields such as tropospheric weather modeling. In the realm of Ionospheric-Thermospheric modeling, the estimation of system drivers is a critical component of any reliable data assimilation technique. How to best estimate and apply these drivers, however, remains an open question and active area of research. The recently developed method of Iterative Re-Initialization, Driver Estimation and Assimilation (IRIDEA) accounts for the driver/response time-delay characteristics of the Ionosphere-Thermosphere system relative to satellite accelerometer observations. Results from two near year-long simulations are shown: (1) from a period of elevated solar and geomagnetic activity during 2003, and (2) from a solar minimum period during 2007. This talk will highlight the challenges and successes of implementing a technique suited for both solar min and max, as well as expectations for improving neutral density forecasts.
Fadel, Ali; Lemaire, Bruno J; Vinçon-Leite, Brigitte; Atoui, Ali; Slim, Kamal; Tassin, Bruno
2017-09-01
Many freshwater bodies worldwide that suffer from harmful algal blooms would benefit for their management from a simple ecological model that requires few field data, e.g. for early warning systems. Beyond a certain degree, adding processes to ecological models can reduce model predictive capabilities. In this work, we assess whether a simple ecological model without nutrients is able to describe the succession of cyanobacterial blooms of different species in a hypereutrophic reservoir and help understand the factors that determine these blooms. In our study site, Karaoun Reservoir, Lebanon, cyanobacteria Aphanizomenon ovalisporum and Microcystis aeruginosa alternatively bloom. A simple configuration of the model DYRESM-CAEDYM was used; both cyanobacteria were simulated, with constant vertical migration velocity for A. ovalisporum, with vertical migration velocity dependent on light for M. aeruginosa and with growth limited by light and temperature and not by nutrients for both species. The model was calibrated on two successive years with contrasted bloom patterns and high variations in water level. It was able to reproduce the measurements; it showed a good performance for the water level (root-mean-square error (RMSE) lower than 1 m, annual variation of 25 m), water temperature profiles (RMSE of 0.22-1.41 °C, range 13-28 °C) and cyanobacteria biomass (RMSE of 1-57 μg Chl a L -1 , range 0-206 μg Chl a L -1 ). The model also helped understand the succession of blooms in both years. The model results suggest that the higher growth rate of M. aeruginosa during favourable temperature and light conditions allowed it to outgrow A. ovalisporum. Our results show that simple model configurations can be sufficient not only for theoretical works when few major processes can be identified but also for operational applications. This approach could be transposed on other hypereutrophic lakes and reservoirs to describe the competition between dominant phytoplankton species, contribute to early warning systems or be used for management scenarios.
Kaplan, Heather C; Provost, Lloyd P; Froehle, Craig M; Margolis, Peter A
2012-01-01
BACKGROUND Quality improvement (QI) efforts have become widespread in healthcare, however there is significant variability in their success. Differences in context are thought to be responsible for some of the variability seen. To develop a conceptual model that can be used by organisations and QI researchers to understand and optimise contextual factors affecting the success of a QI project. 10 QI experts were provided with the results of a systematic literature review and then participated in two rounds of opinion gathering to identify and define important contextual factors. The experts subsequently met in person to identify relationships among factors and to begin to build the model. The Model for Understanding Success in Quality (MUSIQ) is organised based on the level of the healthcare system and identifies 25 contextual factors likely to influence QI success. Contextual factors within microsystems and those related to the QI team are hypothesised to directly shape QI success, whereas factors within the organisation and external environment are believed to influence success indirectly. The MUSIQ framework has the potential to guide the application of QI methods in healthcare and focus research. The specificity of MUSIQ and the explicit delineation of relationships among factors allows a deeper understanding of the mechanism of action by which context influences QI success. MUSIQ also provides a foundation to support further studies to test and refine the theory and advance the field of QI science.
Successful approaches to deploying a metropolitan intelligent transportation system
DOT National Transportation Integrated Search
1999-03-01
On February 26, 1996, the United States Department of Transportation issued a request for participation in the Intelligent Transportation Systems (ITS) Model Deployment Initiative (MDI). The MDIs were envisioned to be demonstrations and showcases of ...
David M. Bell; Andrew N. Gray
2015-01-01
Models of forest succession provide an appealing conceptual framework for understanding forest dynamics, but uncertainty in the degree to which patterns are regionally consistent might limit the application of successional theory in forest management. Remeasurements of forest inventory networks provide an opportunity to assess this consistency, improving our...
Green, Carolyn J; Fortin, Patricia; Maclure, Malcolm; Macgregor, Art; Robinson, Sylvia
2006-12-01
Improvement of chronic disease management in primary care entails monitoring indicators of quality over time and across patients and practices. Informatics tools are needed, yet implementing them remains challenging. To identify critical success factors enabling the translation of clinical and operational knowledge about effective and efficient chronic care management into primary care practice. A prospective case study of positive deviants using key informant interviews, process observation, and document review. A chronic disease management (CDM) collaborative of primary care physicians with documented improvement in adherence to clinical practice guidelines using a web-based patient registry system with CDM guideline-based flow sheet. Thirty community-based physician participants using predominantly paper records, plus a project management team including the physician lead, project manager, evaluator and support team. A critical success factor (CSF) analysis of necessary and sufficient pathways to the translation of knowledge into clinical practice. A web-based CDM 'toolkit' was found to be a direct CSF that allowed this group of physicians to improve their practice by tracking patient care processes using evidence-based clinical practice guideline-based flow sheets. Moreover, the information and communication technology 'factor' was sufficient for success only as part of a set of seven direct CSF components including: health delivery system enhancements, organizational partnerships, funding mechanisms, project management, practice models, and formal knowledge translation practices. Indirect factors that orchestrated success through the direct factor components were also identified. A central insight of this analysis is that a comprehensive quality improvement model was the CSF that drew this set of factors into a functional framework for successful knowledge translation. In complex primary care settings environment where physicians have low adoption rates of electronic tools to support the care of patients with chronic conditions, successful implementation may require a set of interrelated system and technology factors.
PARALLEL MEASUREMENT AND MODELING OF TRANSPORT IN THE DARHT II BEAMLINE ON ETA II
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chambers, F W; Raymond, B A; Falabella, S
To successfully tune the DARHT II transport beamline requires the close coupling of a model of the beam transport and the measurement of the beam observables as the beam conditions and magnet settings are varied. For the ETA II experiment using the DARHT II beamline components this was achieved using the SUICIDE (Simple User Interface Connecting to an Integrated Data Environment) data analysis environment and the FITS (Fully Integrated Transport Simulation) model. The SUICIDE environment has direct access to the experimental beam transport data at acquisition and the FITS predictions of the transport for immediate comparison. The FITS model ismore » coupled into the control system where it can read magnet current settings for real time modeling. We find this integrated coupling is essential for model verification and the successful development of a tuning aid for the efficient convergence on a useable tune. We show the real time comparisons of simulation and experiment and explore the successes and limitations of this close coupled approach.« less
A Product Development Decision Model for Cockpit Weather Information System
NASA Technical Reports Server (NTRS)
Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin; Johnson, Edward J., Jr. (Technical Monitor)
2003-01-01
There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.
A Product Development Decision Model for Cockpit Weather Information Systems
NASA Technical Reports Server (NTRS)
Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin
2003-01-01
There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.
Creating a library holding group: an approach to large system integration.
Huffman, Isaac R; Martin, Heather J; Delawska-Elliott, Basia
2016-10-01
Faced with resource constraints, many hospital libraries have considered joint operations. This case study describes how Providence Health & Services created a single group to provide library services. Using a holding group model, staff worked to unify more than 6,100 nonlibrary subscriptions and 14 internal library sites. Our library services grew by unifying 2,138 nonlibrary subscriptions and 11 library sites and hiring more library staff. We expanded access to 26,018 more patrons. A model with built-in flexibility allowed successful library expansion. Although challenges remain, this success points to a viable model of unified operations.
Physician equity in health care delivery systems: three alternative models.
Kennedy, K M; Wofford, D A
1998-01-01
The 1990s have seen many health care organizations attempting to merge, acquire, or affiliate with physician groups. Many have failed to provide physicians a stake in the success of the newly formed enterprise, frequently resulting in declining physician productivity, poor morale, and large operating losses. These problems warrant a reexamination of the traditional acquisition model of growth in favor of structures that retain a physician ownership component. This article examines three models of health care organization in which physicians share in the success of the enterprise and compares them in terms of ownership structure, governance, and funds flow.
ERIC Educational Resources Information Center
Swan, Edward T.; And Others
This study evaluated the success of Teachers Teaching Teachers, an Indiana staff development model in its first implementation. The project consisted of a cadre of teachers from one school system who trained teachers from four other school systems. Participants were evaluated on nine Likert-type pre- and post-measures at each of the four training…
Energy: Economic activity and energy demand; link to energy flow. Example: France
NASA Astrophysics Data System (ADS)
1980-10-01
The data derived from the EXPLOR and EPOM, Energy Flow Optimization Model are described. The core of the EXPLOR model is a circular system of relations involving consumer's demand, producer's outputs, and market prices. The solution of this system of relations is obtained by successive iterations; the final output is a coherent system of economic accounts. The computer program for this transition is described. The work conducted by comparing different energy demand models is summarized. The procedure is illustrated by a numerical projection to 1980 and 1985 using the existing version of the EXPLOR France model.
Long-term nutrient reductions lead to the unprecedented recovery of a temperate coastal region.
Lefcheck, Jonathan S; Orth, Robert J; Dennison, William C; Wilcox, David J; Murphy, Rebecca R; Keisman, Jennifer; Gurbisz, Cassie; Hannam, Michael; Landry, J Brooke; Moore, Kenneth A; Patrick, Christopher J; Testa, Jeremy; Weller, Donald E; Batiuk, Richard A
2018-04-03
Humans strongly impact the dynamics of coastal systems, yet surprisingly few studies mechanistically link management of anthropogenic stressors and successful restoration of nearshore habitats over large spatial and temporal scales. Such examples are sorely needed to ensure the success of ecosystem restoration efforts worldwide. Here, we unite 30 consecutive years of watershed modeling, biogeochemical data, and comprehensive aerial surveys of Chesapeake Bay, United States to quantify the cascading effects of anthropogenic impacts on submersed aquatic vegetation (SAV), an ecologically and economically valuable habitat. We employ structural equation models to link land use change to higher nutrient loads, which in turn reduce SAV cover through multiple, independent pathways. We also show through our models that high biodiversity of SAV consistently promotes cover, an unexpected finding that corroborates emerging evidence from other terrestrial and marine systems. Due to sustained management actions that have reduced nitrogen concentrations in Chesapeake Bay by 23% since 1984, SAV has regained 17,000 ha to achieve its highest cover in almost half a century. Our study empirically demonstrates that nutrient reductions and biodiversity conservation are effective strategies to aid the successful recovery of degraded systems at regional scales, a finding which is highly relevant to the utility of environmental management programs worldwide.
Modeling Spring Mass System with System Dynamics Approach in Middle School Education
ERIC Educational Resources Information Center
Nuhoglu, Hasret
2008-01-01
System Dynamics is a well formulated methodology for analyzing the components of a system including causeeffect relationships and their underlying mathematics and logic, time delays, and feedback loops. It began in the business and manufacturing world, but is now affecting education and many other disciplines. Having inspired by successful policy…
Modeling Spring Mass System with System Dynamics Approach in Middle School Education
ERIC Educational Resources Information Center
Nuhoglu, Hasret
2008-01-01
System Dynamics is a well formulated methodology for analyzing the components of a system including cause-effect relationships and their underlying mathematics and logic, time delays, and feedback loops. It began in the business and manufacturing world, but is now affecting education and many other disciplines. Having inspired by successful policy…
An ecological process model of systems change.
Peirson, Leslea J; Boydell, Katherine M; Ferguson, H Bruce; Ferris, Lorraine E
2011-06-01
In June 2007 the American Journal of Community Psychology published a special issue focused on theories, methods and interventions for systems change which included calls from the editors and authors for theoretical advancement in this field. We propose a conceptual model of systems change that integrates familiar and fundamental community psychology principles (succession, interdependence, cycling of resources, adaptation) and accentuates a process orientation. To situate our framework we offer a definition of systems change and a brief review of the ecological perspective and principles. The Ecological Process Model of Systems Change is depicted, described and applied to a case example of policy driven systems level change in publicly funded social programs. We conclude by identifying salient implications for thinking and action which flow from the Model.
1990-12-01
Implementation of Coupled System 18 15.4. CASE STUDIES & IMPLEMENTATION EXAMPLES 24 15.4.1. The Case Studies of Coupled System 24 15.4.2. Example: Coupled System...occurs during specific phases of the problem-solving process. By decomposing the coupling process into its component layers we effectively study the nature...by the qualitative model, appropriate mathematical model is invoked. 5) The results are verified. If successful, stop. Else go to (2) and use an
Applying Hierarchical Model Calibration to Automatically Generated Items.
ERIC Educational Resources Information Center
Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.
This study explored the application of hierarchical model calibration as a means of reducing, if not eliminating, the need for pretesting of automatically generated items from a common item model prior to operational use. Ultimately the successful development of automatic item generation (AIG) systems capable of producing items with highly similar…
QSAR models for prediction of chromatographic behavior of homologous Fab variants.
Robinson, Julie R; Karkov, Hanne S; Woo, James A; Krogh, Berit O; Cramer, Steven M
2017-06-01
While quantitative structure activity relationship (QSAR) models have been employed successfully for the prediction of small model protein chromatographic behavior, there have been few reports to date on the use of this methodology for larger, more complex proteins. Recently our group generated focused libraries of antibody Fab fragment variants with different combinations of surface hydrophobicities and electrostatic potentials, and demonstrated that the unique selectivities of multimodal resins can be exploited to separate these Fab variants. In this work, results from linear salt gradient experiments with these Fabs were employed to develop QSAR models for six chromatographic systems, including multimodal (Capto MMC, Nuvia cPrime, and two novel ligand prototypes), hydrophobic interaction chromatography (HIC; Capto Phenyl), and cation exchange (CEX; CM Sepharose FF) resins. The models utilized newly developed "local descriptors" to quantify changes around point mutations in the Fab libraries as well as novel cluster descriptors recently introduced by our group. Subsequent rounds of feature selection and linearized machine learning algorithms were used to generate robust, well-validated models with high training set correlations (R 2 > 0.70) that were well suited for predicting elution salt concentrations in the various systems. The developed models then were used to predict the retention of a deamidated Fab and isotype variants, with varying success. The results represent the first successful utilization of QSAR for the prediction of chromatographic behavior of complex proteins such as Fab fragments in multimodal chromatographic systems. The framework presented here can be employed to facilitate process development for the purification of biological products from product-related impurities by in silico screening of resin alternatives. Biotechnol. Bioeng. 2017;114: 1231-1240. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Graphical Modeling Meets Systems Pharmacology.
Lombardo, Rosario; Priami, Corrado
2017-01-01
A main source of failures in systems projects (including systems pharmacology) is poor communication level and different expectations among the stakeholders. A common and not ambiguous language that is naturally comprehensible by all the involved players is a boost to success. We present bStyle, a modeling tool that adopts a graphical language close enough to cartoons to be a common media to exchange ideas and data and that it is at the same time formal enough to enable modeling, analysis, and dynamic simulations of a system. Data analysis and simulation integrated in the same application are fundamental to understand the mechanisms of actions of drugs: a core aspect of systems pharmacology.
Graphical Modeling Meets Systems Pharmacology
Lombardo, Rosario; Priami, Corrado
2017-01-01
A main source of failures in systems projects (including systems pharmacology) is poor communication level and different expectations among the stakeholders. A common and not ambiguous language that is naturally comprehensible by all the involved players is a boost to success. We present bStyle, a modeling tool that adopts a graphical language close enough to cartoons to be a common media to exchange ideas and data and that it is at the same time formal enough to enable modeling, analysis, and dynamic simulations of a system. Data analysis and simulation integrated in the same application are fundamental to understand the mechanisms of actions of drugs: a core aspect of systems pharmacology. PMID:28469411
Applying Contamination Modelling to Spacecraft Propulsion Systems Designs and Operations
NASA Technical Reports Server (NTRS)
Chen, Philip T.; Thomson, Shaun; Woronowicz, Michael S.
2000-01-01
Molecular and particulate contaminants generated from the operations of a propulsion system may impinge on spacecraft critical surfaces. Plume depositions or clouds may hinder the spacecraft and instruments from performing normal operations. Firing thrusters will generate both molecular and particulate contaminants. How to minimize the contamination impact from the plume becomes very critical for a successful mission. The resulting effect from either molecular or particulate contamination of the thruster firing is very distinct. This paper will discuss the interconnection between the functions of spacecraft contamination modeling and propulsion system implementation. The paper will address an innovative contamination engineering approach implemented from the spacecraft concept design, manufacturing, integration and test (I&T), launch, to on- orbit operations. This paper will also summarize the implementation on several successful missions. Despite other contamination sources, only molecular contamination will be considered here.
Clarity of objectives and working principles enhances the success of biomimetic programs.
Wolff, Jonas O; Wells, David; Reid, Chris R; Blamires, Sean J
2017-09-26
Biomimetics, the transfer of functional principles from living systems into product designs, is increasingly being utilized by engineers. Nevertheless, recurring problems must be overcome if it is to avoid becoming a short-lived fad. Here we assess the efficiency and suitability of methods typically employed by examining three flagship examples of biomimetic design approaches from different disciplines: (1) the creation of gecko-inspired adhesives; (2) the synthesis of spider silk, and (3) the derivation of computer algorithms from natural self-organizing systems. We find that identification of the elemental working principles is the most crucial step in the biomimetic design process. It bears the highest risk of failure (e.g. losing the target function) due to false assumptions about the working principle. Common problems that hamper successful implementation are: (i) a discrepancy between biological functions and the desired properties of the product, (ii) uncertainty about objectives and applications, (iii) inherent limits in methodologies, and (iv) false assumptions about the biology of the models. Projects that aim for multi-functional products are particularly challenging to accomplish. We suggest a simplification, modularisation and specification of objectives, and a critical assessment of the suitability of the model. Comparative analyses, experimental manipulation, and numerical simulations followed by tests of artificial models have led to the successful extraction of working principles. A searchable database of biological systems would optimize the choice of a model system in top-down approaches that start at an engineering problem. Only when biomimetic projects become more predictable will there be wider acceptance of biomimetics as an innovative problem-solving tool among engineers and industry.
Proposal for an integrated evaluation model for the study of whole systems health care in cancer.
Jonas, Wayne B; Beckner, William; Coulter, Ian
2006-12-01
For more than 200 years, biomedicine has approached the treatment of disease by studying disease processes (patho-genesis), inferring causal connections and developing specific approaches for therapeutically interfering with those processes. This pathogenic approach has been highly successful in acute and traumatic disease but less successful in chronic disease, primarily because of the complex, multi-factorial nature of most chronic disease, which does not allow for simple causal inference or for simple therapeutic interventions. This article suggests that chronic disease is best approached by enhancing healing processes (salutogenesis) as a whole system. Because of the nature of complex systems in chronic disease, an evaluation model based on integrative medicine is felt to be more appropriate than a disease model. The authors propose and describe an integrated model for the evaluation of healing (IMEH) that collects multilevel "thick case" observational data in assessing complex practices for chronic disease. If successful, this approach could become a blueprint for studying healing capacity in whole medical systems, including complementary medicine, traditional medicine, and conventional primary care. In addition, streamlining data collection and applying rapid informatics management might allow for such data to be used in guiding clinical practice. The IMEH involves collection, integration, and potentially feedback of relevant variables in the following areas: (1) sociocultural, (2) psychological and behavioral, (3) clinical (diagnosis based), and (4) biological. Evaluation and integration of these components would involve specialized research teams that feed their data into a single data management and information analysis center. These data can then be subjected to descriptive and pathway analysis providing "bench and bedside" information.
Exploring the possibility of modeling a genetic counseling guideline using agile methodology.
Choi, Jeeyae
2013-01-01
Increased demand of genetic counseling services heightened the necessity of a computerized genetic counseling decision support system. In order to develop an effective and efficient computerized system, modeling of genetic counseling guideline is an essential step. Throughout this pilot study, Agile methodology with United Modeling Language (UML) was utilized to model a guideline. 13 tasks and 14 associated elements were extracted. Successfully constructed conceptual class and activity diagrams revealed that Agile methodology with UML was a suitable tool to modeling a genetic counseling guideline.
Changing the Officer Promotion System to Support Unit Focused Stability (UFS)
2005-05-26
arms officers will be reduced by one-third.78 This decrement is far from trivial. Since many combat arms officers define career success by these two...their own priorities and definitions of career success , or by inventing informal “work-arounds” to regain the status quo of the old personnel...progression models so that its members are not forced to choose between personal career success and unit cohesion? Perhaps a study of the officer
Operational Performance Risk Assessment in Support of A Supervisory Control System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Denning, Richard S.; Muhlheim, Michael David; Cetiner, Sacit M.
Supervisory control system (SCS) is developed for multi-unit advanced small modular reactors to minimize human interventions in both normal and abnormal operations. In SCS, control action decisions made based on probabilistic risk assessment approach via Event Trees/Fault Trees. Although traditional PRA tools are implemented, their scope is extended to normal operations and application is reversed; success of non-safety related system instead failure of safety systems this extended PRA approach called as operational performance risk assessment (OPRA). OPRA helps to identify success paths, combination of control actions for transients and to quantify these success paths to provide possible actions without activatingmore » plant protection system. In this paper, a case study of the OPRA in supervisory control system is demonstrated within the context of the ALMR PRISM design, specifically power conversion system. The scenario investigated involved a condition that the feed water control valve is observed to be drifting to the closed position. Alternative plant configurations were identified via OPRA that would allow the plant to continue to operate at full or reduced power. Dynamic analyses were performed with a thermal-hydraulic model of the ALMR PRISM system using Modelica to evaluate remained safety margins. Successful recovery paths for the selected scenario are identified and quantified via SCS.« less
NASA Astrophysics Data System (ADS)
Malard, J. J.; Baig, A. I.; Carrera, J.; Mellini, L.; Pineda, P.; Monterroso, O.; Melgar-Quiñonez, H.; Adamowski, J. F.; Halbe, J.; Monardes, H.; Gálvez, J.
2014-12-01
The design of effective management policies for socioenvironmental systems requires the development of comprehensive, yet sufficiently simple, decision support systems (DSS) for policy makers. Guatemala is a particularly complex case, combining an enormous diversity of climates, geographies, and agroecosystems within a very small geographical scale. Although food insecurity levels are very high, indicating a generally inadequate management of the varied agroecosystems of the country, different regions have shown vastly different trends in food insecurity over the past decade, including between regions with similar geophysical and climatic characteristics and/or governmental programmes (e.g., agricultural support). These observations suggest two important points: firstly, that not merely environmental conditions but rather socio-environmental interactions play a crucial role in the successful management of human-environmental systems, and, secondly, that differences in the geophysical and climatic environments between the diverse regions significantly impact the success or failure of policies. This research uses participatory systems dynamic modelling (SDM) to build a DSS that allows local decision-makers to (1) determine the impact of current and potential policies on agroecosystem management and food security, and (2) design sustainable and resilient policies for the future. The use of participatory SDM offers several benefits, including the active involvement of the end recipients in the development of the model, greatly increasing its acceptability; the integration of physical (e.g., precipitation, crop yield) and social components in one model; adequacy for modelling long-term trends in response to particular policy decisions; and the inclusion of local stakeholder knowledge on system structure and trends through the participatory process. Preliminary results suggest that there is a set of common variables explaining the generally high levels of food insecurity in Guatemala (e.g., agricultural productivity), while others (e.g., land dynamics and access to water resources) are restricted to certain regions and have a relatively important weight in determining the success or failure of policies in these regions.
Radar studies related to the earth resources program. [remote sensing programs
NASA Technical Reports Server (NTRS)
Holtzman, J.
1972-01-01
The radar systems research discussed is directed toward achieving successful application of radar to remote sensing problems in such areas as geology, hydrology, agriculture, geography, forestry, and oceanography. Topics discussed include imaging radar and evaluation of its modification, study of digital processing for synthetic aperture system, digital simulation of synthetic aperture system, averaging techniques studies, ultrasonic modeling of panchromatic system, panchromatic radar/radar spectrometer development, measuring octave-bandwidth response of selected targets, scatterometer system analysis, and a model Fresnel-zone processor for synthetic aperture imagery.
Advanced reliability modeling of fault-tolerant computer-based systems
NASA Technical Reports Server (NTRS)
Bavuso, S. J.
1982-01-01
Two methodologies for the reliability assessment of fault tolerant digital computer based systems are discussed. The computer-aided reliability estimation 3 (CARE 3) and gate logic software simulation (GLOSS) are assessment technologies that were developed to mitigate a serious weakness in the design and evaluation process of ultrareliable digital systems. The weak link is based on the unavailability of a sufficiently powerful modeling technique for comparing the stochastic attributes of one system against others. Some of the more interesting attributes are reliability, system survival, safety, and mission success.
Fix success and accuracy of GPS radio collars in old-growth temperate coniferous forests
Sager-Fradkin, Kimberly A.; Jenkins, Kurt J.; Hoffman, Robert L.; Happe, P.; Beecham, J.; Wright, R.G.
2007-01-01
Global Positioning System (GPS) telemetry is used extensively to study animal distribution and resource selection patterns but is susceptible to biases resulting from data omission and spatial inaccuracies. These data errors may cause misinterpretation of wildlife habitat selection or spatial use patterns. We used both stationary test collars and collared free-ranging American black bears (Ursus americanus) to quantify systemic data loss and location error of GPS telemetry in mountainous, old-growth temperate forests of Olympic National Park, Washington, USA. We developed predictive models of environmental factors that influence the probability of obtaining GPS locations and evaluated the ability of weighting factors derived from these models to mitigate data omission biases from collared bears. We also examined the effects of microhabitat on collar fix success rate and examined collar accuracy as related to elevation changes between successive fixes. The probability of collars successfully obtaining location fixes was positively associated with elevation and unobstructed satellite view and was negatively affected by the interaction of overstory canopy and satellite view. Test collars were 33% more successful at acquiring fixes than those on bears. Fix success rates of collared bears varied seasonally and diurnally. Application of weighting factors to individual collared bear fixes recouped only 6% of lost data and failed to reduce seasonal or diurnal variation in fix success, suggesting that variables not included in our model contributed to data loss. Test collars placed to mimic bear bedding sites received 16% fewer fixes than randomly placed collars, indicating that microhabitat selection may contribute to data loss for wildlife equipped with GPS collars. Horizontal collar errors of >800 m occurred when elevation changes between successive fixes were >400 m. We conclude that significant limitations remain in accounting for data loss and error inherent in using GPS telemetry in coniferous forest ecosystems and that, at present, resource selection patterns of large mammals derived from GPS telemetry should be interpreted cautiously.
The Flipped Classroom Model and Academic Achievement: A Pre and Posttest Comparison Groups Study
ERIC Educational Resources Information Center
Wenzler, Heather Rebecca
2017-01-01
Student academic achievement is of prime concern in the American education system because academic success (i.e. achievement) has been shown to be a predictor of success in later life and is crystallized in the United States Department of Education's mission statement "...to promote student achievement and preparation for global…
Talent Development as an Ecology of Games: A Case Study of Norwegian Handball
ERIC Educational Resources Information Center
Bjørndal, Christian Thue; Ronglan, Lars Tore; Andersen, Svein S.
2017-01-01
Structured talent identification and development, it has been argued, is one of the foundations of international sporting success and many modern elite sport systems have applied normative talent development (TD) models. The success of Norwegian handball, however, is based on an alternative approach to TD. Norwegian handball is characterized by a…
The shifting influence of abiotic drivers during landslide succession in Puerto Rico
L. R. Walker; A. B. Shiels; P. J. Bellingham; A. D. Sparrow; N. Fetcher; F. H. Landau; D. J. Lodge
2013-01-01
Summary 1. Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. 2. In...
ERIC Educational Resources Information Center
Kaikkonen, Darby
2016-01-01
Performance-based funding (PBF) in higher education has grown in recent years as a means of institutional accountability and incentive for improving student success. Although most states have successfully implemented their respective systems, research on early funding models suggests a difficult fiscal environment can introduce tension between…
ERIC Educational Resources Information Center
Hansen, Duncan N.; And Others
Computer simulations of three individualized adaptive instructional models (AIM) were undertaken to determine if these models function as prescribed in Air Force technical training programs. In addition, the project sought to develop a user's guide for effective understanding of adaptive models during field implementation. Successful simulations…
Methods for Probabilistic Fault Diagnosis: An Electrical Power System Case Study
NASA Technical Reports Server (NTRS)
Ricks, Brian W.; Mengshoel, Ole J.
2009-01-01
Health management systems that more accurately and quickly diagnose faults that may occur in different technical systems on-board a vehicle will play a key role in the success of future NASA missions. We discuss in this paper the diagnosis of abrupt continuous (or parametric) faults within the context of probabilistic graphical models, more specifically Bayesian networks that are compiled to arithmetic circuits. This paper extends our previous research, within the same probabilistic setting, on diagnosis of abrupt discrete faults. Our approach and diagnostic algorithm ProDiagnose are domain-independent; however we use an electrical power system testbed called ADAPT as a case study. In one set of ADAPT experiments, performed as part of the 2009 Diagnostic Challenge, our system turned out to have the best performance among all competitors. In a second set of experiments, we show how we have recently further significantly improved the performance of the probabilistic model of ADAPT. While these experiments are obtained for an electrical power system testbed, we believe they can easily be transitioned to real-world systems, thus promising to increase the success of future NASA missions.
The past, present and future of cyber-physical systems: a focus on models.
Lee, Edward A
2015-02-26
This paper is about better engineering of cyber-physical systems (CPSs) through better models. Deterministic models have historically proven extremely useful and arguably form the kingpin of the industrial revolution and the digital and information technology revolutions. Key deterministic models that have proven successful include differential equations, synchronous digital logic and single-threaded imperative programs. Cyber-physical systems, however, combine these models in such a way that determinism is not preserved. Two projects show that deterministic CPS models with faithful physical realizations are possible and practical. The first project is PRET, which shows that the timing precision of synchronous digital logic can be practically made available at the software level of abstraction. The second project is Ptides (programming temporally-integrated distributed embedded systems), which shows that deterministic models for distributed cyber-physical systems have practical faithful realizations. These projects are existence proofs that deterministic CPS models are possible and practical.
The Past, Present and Future of Cyber-Physical Systems: A Focus on Models
Lee, Edward A.
2015-01-01
This paper is about better engineering of cyber-physical systems (CPSs) through better models. Deterministic models have historically proven extremely useful and arguably form the kingpin of the industrial revolution and the digital and information technology revolutions. Key deterministic models that have proven successful include differential equations, synchronous digital logic and single-threaded imperative programs. Cyber-physical systems, however, combine these models in such a way that determinism is not preserved. Two projects show that deterministic CPS models with faithful physical realizations are possible and practical. The first project is PRET, which shows that the timing precision of synchronous digital logic can be practically made available at the software level of abstraction. The second project is Ptides (programming temporally-integrated distributed embedded systems), which shows that deterministic models for distributed cyber-physical systems have practical faithful realizations. These projects are existence proofs that deterministic CPS models are possible and practical. PMID:25730486
Dini-Andreote, Francisco; Stegen, James C.; van Elsas, Jan D.; ...
2015-03-17
Despite growing recognition that deterministic and stochastic factors simultaneously influence bacterial communities, little is known about mechanisms shifting their relative importance. To better understand underlying mechanisms, we developed a conceptual model linking ecosystem development during primary succession to shifts in the stochastic/deterministic balance. To evaluate the conceptual model we coupled spatiotemporal data on soil bacterial communities with environmental conditions spanning 105 years of salt marsh development. At the local scale there was a progression from stochasticity to determinism due to Na accumulation with increasing ecosystem age, supporting a main element of the conceptual model. At the regional-scale, soil organic mattermore » (SOM) governed the relative influence of stochasticity and the type of deterministic ecological selection, suggesting scale-dependency in how deterministic ecological selection is imposed. Analysis of a new ecological simulation model supported these conceptual inferences. Looking forward, we propose an extended conceptual model that integrates primary and secondary succession in microbial systems.« less
Critical success factors for achieving superior m-health success.
Dwivedi, A; Wickramasinghe, N; Bali, R K; Naguib, R N G
2007-01-01
Recent healthcare trends clearly show significant investment by healthcare institutions into various types of wired and wireless technologies to facilitate and support superior healthcare delivery. This trend has been spurred by the shift in the concept and growing importance of the role of health information and the influence of fields such as bio-informatics, biomedical and genetic engineering. The demand is currently for integrated healthcare information systems; however for such initiatives to be successful it is necessary to adopt a macro model and appropriate methodology with respect to wireless initiatives. The key contribution of this paper is the presentation of one such integrative model for mobile health (m-health) known as the Wi-INET Business Model, along with a detailed Adaptive Mapping to Realisation (AMR) methodology. The AMR methodology details how the Wi-INET Business Model can be implemented. Further validation on the concepts detailed in the Wi-INET Business Model and the AMR methodology is offered via a short vignette on a toolkit based on a leading UK-based healthcare information technology solution.
Factors affecting success of an integrated community-based telehealth system.
Hsieh, Hui-Lung; Tsai, Chung-Hung; Chih, Wen-Hai; Lin, Huei-Hsieh
2015-01-01
The rise of chronic and degenerative diseases in developed countries has become one critical epidemiologic issue. Telehealth can provide one viable way to enhance health care, public health, and health education delivery and support. The study aims to empirically examine and evaluate the success factors of community-based telehealth system adoption. The valid 336 respondents are the residents of a rural community in Taiwan. The structural equation modeling (SEM) was used to assess the proposed model applied to telehealth. The findings showed the research model had good explanatory power and fitness. Also, the findings indicated that system quality exerted the strongest overall effect on intention to use. Furthermore, service quality exerted the strongest overall effect on user satisfaction. The findings also illustrated that the joint effects of three intrinsic qualities (system quality, information quality, and service quality) on use were mediated by user satisfaction and intention to use. The study implies that community-based telehealth service providers should improve three intrinsic qualities to enhance user satisfaction and intention to use, which in turn can lead to increase the usage of the telehealth equipment. The integrated community-based telehealth system may become an innovative and suitable way to deliver better care to the residents of communities.
Biomedical systems analysis program
NASA Technical Reports Server (NTRS)
1979-01-01
Biomedical monitoring programs which were developed to provide a system analysis context for a unified hypothesis for adaptation to space flight are presented and discussed. A real-time system of data analysis and decision making to assure the greatest possible crew safety and mission success is described. Information about man's abilities, limitations, and characteristic reactions to weightless space flight was analyzed and simulation models were developed. The predictive capabilities of simulation models for fluid-electrolyte regulation, erythropoiesis regulation, and calcium regulation are discussed.
Generation of infectious recombinant Adeno-associated virus in Saccharomyces cerevisiae.
Barajas, Daniel; Aponte-Ubillus, Juan Jose; Akeefe, Hassibullah; Cinek, Tomas; Peltier, Joseph; Gold, Daniel
2017-01-01
The yeast Saccharomyces cerevisiae has been successfully employed to establish model systems for a number of viruses. Such model systems are powerful tools to study the virus biology and in particular for the identification and characterization of host factors playing a role in the viral infection cycle. Adeno-associated viruses (AAV) are heavily studied due to their use as gene delivery vectors. AAV relies on other helper viruses for successful replication and on host factors for several aspects of the viral life cycle. However the role of host and helper viral factors is only partially known. Production of recombinant AAV (rAAV) vectors for gene delivery applications depends on knowledge of AAV biology and the limited understanding of host and helper viral factors may be precluding efficient production, particularly in heterologous systems. Model systems in simpler eukaryotes like the yeast S. cerevisiae would be useful tools to identify and study the role of host factors in AAV biology. Here we show that expression of AAV2 viral proteins VP1, VP2, VP3, AAP, Rep78, Rep52 and an ITR-flanked DNA in yeast leads to capsid formation, DNA replication and encapsidation, resulting in formation of infectious particles. Many of the AAV characteristics observed in yeast resemble those in other systems, making it a suitable model system. Future findings in the yeast system could be translatable to other AAV host systems and aid in more efficient production of rAAV vectors.
Identifying Model-Based Reconfiguration Goals through Functional Deficiencies
NASA Technical Reports Server (NTRS)
Benazera, Emmanuel; Trave-Massuyes, Louise
2004-01-01
Model-based diagnosis is now advanced to the point autonomous systems face some uncertain and faulty situations with success. The next step toward more autonomy is to have the system recovering itself after faults occur, a process known as model-based reconfiguration. After faults occur, given a prediction of the nominal behavior of the system and the result of the diagnosis operation, this paper details how to automatically determine the functional deficiencies of the system. These deficiencies are characterized in the case of uncertain state estimates. A methodology is then presented to determine the reconfiguration goals based on the deficiencies. Finally, a recovery process interleaves planning and model predictive control to restore the functionalities in prioritized order.
Model-Based Systems Engineering Pilot Program at NASA Langley
NASA Technical Reports Server (NTRS)
Vipavetz, Kevin G.; Murphy, Douglas G.; Infeld, Samatha I.
2012-01-01
NASA Langley Research Center conducted a pilot program to evaluate the benefits of using a Model-Based Systems Engineering (MBSE) approach during the early phase of the Materials International Space Station Experiment-X (MISSE-X) project. The goal of the pilot was to leverage MBSE tools and methods, including the Systems Modeling Language (SysML), to understand the net gain of utilizing this approach on a moderate size flight project. The System Requirements Review (SRR) success criteria were used to guide the work products desired from the pilot. This paper discusses the pilot project implementation, provides SysML model examples, identifies lessons learned, and describes plans for further use on MBSE on MISSE-X.
Development of a category 2 approach system model
NASA Technical Reports Server (NTRS)
Johnson, W. A.; Mcruer, D. T.
1972-01-01
An analytical model is presented which provides, as its primary output, the probability of a successful Category II approach. Typical applications are included using several example systems (manual and automatic) which are subjected to random gusts and deterministic wind shear. The primary purpose of the approach system model is to establish a structure containing the system elements, command inputs, disturbances, and their interactions in an analytical framework so that the relative effects of changes in the various system elements on precision of control and available margins of safety can be estimated. The model is intended to provide insight for the design and integration of suitable autopilot, display, and navigation elements; and to assess the interaction of such elements with the pilot/copilot.
An Evaluation of Turkish Teacher Education System Compared to Other Models in Different Countries
ERIC Educational Resources Information Center
Duman, Tayyip; Karagöz, Savas
2016-01-01
Teachers and their education, as the most important elements in educational systems, have been one of the mostly debated issues in Turkish national education system. The success of an education system largely depends on the quality of the teachers who plan and practice teaching and learning process. Reviewing Turkish educational history with a…
Systems Genetics as a Tool to Identify Master Genetic Regulators in Complex Disease.
Moreno-Moral, Aida; Pesce, Francesco; Behmoaras, Jacques; Petretto, Enrico
2017-01-01
Systems genetics stems from systems biology and similarly employs integrative modeling approaches to describe the perturbations and phenotypic effects observed in a complex system. However, in the case of systems genetics the main source of perturbation is naturally occurring genetic variation, which can be analyzed at the systems-level to explain the observed variation in phenotypic traits. In contrast with conventional single-variant association approaches, the success of systems genetics has been in the identification of gene networks and molecular pathways that underlie complex disease. In addition, systems genetics has proven useful in the discovery of master trans-acting genetic regulators of functional networks and pathways, which in many cases revealed unexpected gene targets for disease. Here we detail the central components of a fully integrated systems genetics approach to complex disease, starting from assessment of genetic and gene expression variation, linking DNA sequence variation to mRNA (expression QTL mapping), gene regulatory network analysis and mapping the genetic control of regulatory networks. By summarizing a few illustrative (and successful) examples, we highlight how different data-modeling strategies can be effectively integrated in a systems genetics study.
BehavePlus fire modeling system: Past, present, and future
Patricia L. Andrews
2007-01-01
Use of mathematical fire models to predict fire behavior and fire effects plays an important supporting role in wildland fire management. When used in conjunction with personal fire experience and a basic understanding of the fire models, predictions can be successfully applied to a range of fire management activities including wildfire behavior prediction, prescribed...
Flexible Approximation Model Approach for Bi-Level Integrated System Synthesis
NASA Technical Reports Server (NTRS)
Sobieszczanski-Sobieski, Jaroslaw; Kim, Hongman; Ragon, Scott; Soremekun, Grant; Malone, Brett
2004-01-01
Bi-Level Integrated System Synthesis (BLISS) is an approach that allows design problems to be naturally decomposed into a set of subsystem optimizations and a single system optimization. In the BLISS approach, approximate mathematical models are used to transfer information from the subsystem optimizations to the system optimization. Accurate approximation models are therefore critical to the success of the BLISS procedure. In this paper, new capabilities that are being developed to generate accurate approximation models for BLISS procedure will be described. The benefits of using flexible approximation models such as Kriging will be demonstrated in terms of convergence characteristics and computational cost. An approach of dealing with cases where subsystem optimization cannot find a feasible design will be investigated by using the new flexible approximation models for the violated local constraints.
Business model design for a wearable biofeedback system.
Hidefjäll, Patrik; Titkova, Dina
2015-01-01
Wearable sensor technologies used to track daily activities have become successful in the consumer market. In order for wearable sensor technology to offer added value in the more challenging areas of stress-rehab care and occupational health stress-related biofeedback parameters need to be monitored and more elaborate business models are needed. To identify probable success factors for a wearable biofeedback system (Affective Health) in the two mentioned market segments in a Swedish setting, we conducted literature studies and interviews with relevant representatives. Data were collected and used first to describe the two market segments and then to define likely feasible business model designs, according to the Business Model Canvas framework. Needs of stakeholders were identified as inputs to business model design. Value propositions, a key building block of a business model, were defined for each segment. The value proposition for occupational health was defined as "A tool that can both identify employees at risk of stress-related disorders and reinforce healthy sustainable behavior" and for healthcare as: "Providing therapists with objective data about the patient's emotional state and motivating patients to better engage in the treatment process".
NASA Technical Reports Server (NTRS)
Yuchnovicz, Daniel E.; Dennehy, Cornelius J.; Schuster, David M.
2011-01-01
The National Aeronautics and Space Administration (NASA) Engineering and Safety Center was chartered to develop an alternate launch abort system (LAS) as risk mitigation for the Orion Project. Its successful flight test provided data for the design of future LAS vehicles. Design of the flight test vehicle (FTV) and pad abort trajectory relied heavily on modeling and simulation including computational fluid dynamics for vehicle aero modeling, 6-degree-of-freedom kinematics models for flight trajectory modeling, and 3-degree-of-freedom kinematics models for parachute force modeling. This paper highlights the simulation techniques and the interaction between the aerodynamics, flight mechanics, and aerodynamic decelerator disciplines during development of the Max Launch Abort System FTV.
NASA Astrophysics Data System (ADS)
Jia, Chaoqing; Hu, Jun; Chen, Dongyan; Liu, Yurong; Alsaadi, Fuad E.
2018-07-01
In this paper, we discuss the event-triggered resilient filtering problem for a class of time-varying systems subject to stochastic uncertainties and successive packet dropouts. The event-triggered mechanism is employed with hope to reduce the communication burden and save network resources. The stochastic uncertainties are considered to describe the modelling errors and the phenomenon of successive packet dropouts is characterized by a random variable obeying the Bernoulli distribution. The aim of the paper is to provide a resilient event-based filtering approach for addressed time-varying systems such that, for all stochastic uncertainties, successive packet dropouts and filter gain perturbation, an optimized upper bound of the filtering error covariance is obtained by designing the filter gain. Finally, simulations are provided to demonstrate the effectiveness of the proposed robust optimal filtering strategy.
The computational future for climate and Earth system models: on the path to petaflop and beyond.
Washington, Warren M; Buja, Lawrence; Craig, Anthony
2009-03-13
The development of the climate and Earth system models has had a long history, starting with the building of individual atmospheric, ocean, sea ice, land vegetation, biogeochemical, glacial and ecological model components. The early researchers were much aware of the long-term goal of building the Earth system models that would go beyond what is usually included in the climate models by adding interactive biogeochemical interactions. In the early days, the progress was limited by computer capability, as well as by our knowledge of the physical and chemical processes. Over the last few decades, there has been much improved knowledge, better observations for validation and more powerful supercomputer systems that are increasingly meeting the new challenges of comprehensive models. Some of the climate model history will be presented, along with some of the successes and difficulties encountered with present-day supercomputer systems.
NASA's Space Launch System: Systems Engineering Approach for Affordability and Mission Success
NASA Technical Reports Server (NTRS)
Hutt, John J.; Whitehead, Josh; Hanson, John
2017-01-01
NASA is working toward the first launch of the Space Launch System, a new, unmatched capability for deep space exploration with launch readiness planned for 2019. Since program start in 2011, SLS has passed several major formal design milestones, and every major element of the vehicle has produced test and flight hardware. The SLS approach to systems engineering has been key to the program's success. Key aspects of the SLS SE&I approach include: 1) minimizing the number of requirements, 2) elimination of explicit verification requirements, 3) use of certified models of subsystem capability in lieu of requirements when appropriate and 4) certification of capability beyond minimum required capability.
Coping with Variability in Model-Based Systems Engineering: An Experience in Green Energy
NASA Astrophysics Data System (ADS)
Trujillo, Salvador; Garate, Jose Miguel; Lopez-Herrejon, Roberto Erick; Mendialdua, Xabier; Rosado, Albert; Egyed, Alexander; Krueger, Charles W.; de Sosa, Josune
Model-Based Systems Engineering (MBSE) is an emerging engineering discipline whose driving motivation is to provide support throughout the entire system life cycle. MBSE not only addresses the engineering of software systems but also their interplay with physical systems. Quite frequently, successful systems need to be customized to cater for the concrete and specific needs of customers, end-users, and other stakeholders. To effectively meet this demand, it is vital to have in place mechanisms to cope with the variability, the capacity to change, that such customization requires. In this paper we describe our experience in modeling variability using SysML, a leading MBSE language, for developing a product line of wind turbine systems used for the generation of electricity.
Time-lapse cinematography in living Drosophila tissues: preparation of material.
Davis, Ilan; Parton, Richard M
2006-11-01
The fruit fly, Drosophila melanogaster, has been an extraordinarily successful model organism for studying the genetic basis of development and evolution. It is arguably the best-understood complex multicellular model system, owing its success to many factors. Recent developments in imaging techniques, in particular sophisticated fluorescence microscopy methods and equipment, now allow cellular events to be studied at high resolution in living material. This ability has enabled the study of features that tend to be lost or damaged by fixation, such as transient or dynamic events. Although many of the techniques of live cell imaging in Drosophila are shared with the greater community of cell biologists working on other model systems, studying living fly tissues presents unique difficulties in keeping the cells alive, introducing fluorescent probes, and imaging through thick hazy cytoplasm. This protocol outlines the preparation of major tissue types amenable to study by time-lapse cinematography and different methods for keeping them alive.
Effectiveness of e-learning in hospitals.
Chuo, Yinghsiang; Liu, Chuangchun; Tsai, Chunghung
2015-01-01
Because medical personnel share different work shifts (i.e., three work shifts) and do not have a fixed work schedule, implementing timely, flexible, and quick e-learning methods for their continued education is imperative. Hospitals are currently focusing on developing e-learning. This study aims to explore the key factors that influence the effectiveness of e-learning in medical personnel. This study recruited medical personnel as the study participants and collected sample data by using the questionnaire survey method. This study is based on the information systems success model (IS success model), a significant model in MIS research. This study found that the factors (i.e., information quality, service quality, convenience, and learning climate) influence the e-learning satisfaction and in turn influence effectiveness in medical personnel. This study provided recommendations to medical institutions according to the derived findings, which can be used as a reference when establishing e-learning systems in the future.
ERIC Educational Resources Information Center
Findik Coskuncay, Duygu; Ozkan, Sevgi
2013-01-01
Through the rapid expansion of information technologies, Learning Management Systems have become one of the most important innovations for delivering education. However, successful implementation and management of these systems are primarily based on the instructors' adoption. In this context, this study aims to understand behavioral intentions…
Human Systems Integration at NASA Ames Research Center
NASA Technical Reports Server (NTRS)
McCandless, Jeffrey
2017-01-01
The Human Systems Integration Division focuses on the design and operations of complex aerospace systems through analysis, experimentation and modeling. With over a dozen labs and over 120 people, the division conducts research to improve safety, efficiency and mission success. Areas of investigation include applied vision research which will be discussed during this seminar.
Design and fabrication of complete dentures using CAD/CAM technology
Han, Weili; Li, Yanfeng; Zhang, Yue; lv, Yuan; Zhang, Ying; Hu, Ping; Liu, Huanyue; Ma, Zheng; Shen, Yi
2017-01-01
Abstract The aim of the study was to test the feasibility of using commercially available computer-aided design and computer-aided manufacturing (CAD/CAM) technology including 3Shape Dental System 2013 trial version, WIELAND V2.0.049 and WIELAND ZENOTEC T1 milling machine to design and fabricate complete dentures. The modeling process of full denture available in the trial version of 3Shape Dental System 2013 was used to design virtual complete dentures on the basis of 3-dimensional (3D) digital edentulous models generated from the physical models. The virtual complete dentures designed were exported to CAM software of WIELAND V2.0.049. A WIELAND ZENOTEC T1 milling machine controlled by the CAM software was used to fabricate physical dentitions and baseplates by milling acrylic resin composite plates. The physical dentitions were bonded to the corresponding baseplates to form the maxillary and mandibular complete dentures. Virtual complete dentures were successfully designed using the software through several steps including generation of 3D digital edentulous models, model analysis, arrangement of artificial teeth, trimming relief area, and occlusal adjustment. Physical dentitions and baseplates were successfully fabricated according to the designed virtual complete dentures using milling machine controlled by a CAM software. Bonding physical dentitions to the corresponding baseplates generated the final physical complete dentures. Our study demonstrated that complete dentures could be successfully designed and fabricated by using CAD/CAM. PMID:28072686
A wind-tunnel investigation of a B-52 model flutter suppression system
NASA Technical Reports Server (NTRS)
Redd, L. T.; Gilman, J., Jr.; Cooley, D. E.; Sevart, F. D.
1974-01-01
Flutter modeling techniques have been successfully extended to the difficult case of the active suppression of flutter. The demonstration was conducted in a transonic dynamics tunnel using a 1/30 scale, elastic, dynamic model of a Boeing B-52 control configured vehicle. The results from the study show that with the flutter suppression system operating there is a substantial increase in the damping associated with the critical flutter mode. The results also show good correlation between the damping characteristics of the model and the aircraft.
Dynamics Simulation Model for Space Tethers
NASA Technical Reports Server (NTRS)
Levin, E. M.; Pearson, J.; Oldson, J. C.
2006-01-01
This document describes the development of an accurate model for the dynamics of the Momentum Exchange Electrodynamic Reboost (MXER) system. The MXER is a rotating tether about 100-km long in elliptical Earth orbit designed to catch payloads in low Earth orbit and throw them to geosynchronous orbit or to Earth escape. To ensure successful rendezvous between the MXER tip catcher and a payload, a high-fidelity model of the system dynamics is required. The model developed here quantifies the major environmental perturbations, and can predict the MXER tip position to within meters over one orbit.
Wind energy system time-domain (WEST) analyzers
NASA Technical Reports Server (NTRS)
Dreier, M. E.; Hoffman, J. A.
1981-01-01
A portable analyzer which simulates in real time the complex nonlinear dynamics of horizontal axis wind energy systems was constructed. Math models for an aeroelastic rotor featuring nonlinear aerodynamic and inertial terms were implemented with high speed digital controllers and analog calculation. This model was combined with other math models of elastic supports, control systems, a power train and gimballed rotor kinematics. A stroboscopic display system graphically depicting distributed blade loads, motion, and other aerodynamic functions on a cathode ray tube is included. Limited correlation efforts showed good comparison between the results of this analyzer and other sophisticated digital simulations. The digital simulation results were successfully correlated with test data.
Gomez-Ramirez, Jaime; Sanz, Ricardo
2013-09-01
One of the most important scientific challenges today is the quantitative and predictive understanding of biological function. Classical mathematical and computational approaches have been enormously successful in modeling inert matter, but they may be inadequate to address inherent features of biological systems. We address the conceptual and methodological obstacles that lie in the inverse problem in biological systems modeling. We introduce a full Bayesian approach (FBA), a theoretical framework to study biological function, in which probability distributions are conditional on biophysical information that physically resides in the biological system that is studied by the scientist. Copyright © 2013 Elsevier Ltd. All rights reserved.
A simulation model for probabilistic analysis of Space Shuttle abort modes
NASA Technical Reports Server (NTRS)
Hage, R. T.
1993-01-01
A simulation model which was developed to provide a probabilistic analysis tool to study the various space transportation system abort mode situations is presented. The simulation model is based on Monte Carlo simulation of an event-tree diagram which accounts for events during the space transportation system's ascent and its abort modes. The simulation model considers just the propulsion elements of the shuttle system (i.e., external tank, main engines, and solid boosters). The model was developed to provide a better understanding of the probability of occurrence and successful completion of abort modes during the vehicle's ascent. The results of the simulation runs discussed are for demonstration purposes only, they are not official NASA probability estimates.
Archetypal dynamics, emergent situations, and the reality game.
Sulis, William
2010-07-01
The classical approach to the modeling of reality is founded upon its objectification. Although successful dealing with inanimate matter, objectification has proven to be much less successful elsewhere, sometimes to the point of paradox. This paper discusses an approach to the modeling of reality based upon the concept of process as formulated within the framework of archetypal dynamics. Reality is conceptualized as an intermingling of information-transducing systems, together with the semantic frames that effectively describe and ascribe meaning to each system, along with particular formal representations of same which constitute the archetypes. Archetypal dynamics is the study of the relationships between systems, frames and their representations and the flow of information among these different entities. In this paper a specific formal representation of archetypal dynamics using tapestries is given, and a dynamics is founded upon this representation in the form of a combinatorial game called a reality game. Some simple examples are presented.
Mattke, Soeren; Liu, Hangsheng; Hunter, Lauren E; Gu, Kun; Newberry, Sydne
2014-12-30
After having successfully expanded health insurance coverage, China now faces the challenge of building an effective and efficient delivery system to serve its large and aging population. The country finds itself at a crossroads-it can emulate the models of Western countries with their well-known limitations, or embark on an ambitious endeavor to create an innovative and sustainable model. We recommend that China choose the second option and design and implement a health care system based on population health management principles and sophisticated health information technology. Taking this path could yield a triple dividend for China: Health care will contribute to the growth of service sector employment, stimulate domestic demand by unlocking savings, and enable China to export its health system development capabilities to other emerging economies, mirroring its success in building other critical infrastructure. These forces can help turn the Chinese Dream into a reality.
Coupling population dynamics with earth system models: the POPEM model.
Navarro, Andrés; Moreno, Raúl; Jiménez-Alcázar, Alfonso; Tapiador, Francisco J
2017-09-16
Precise modeling of CO 2 emissions is important for environmental research. This paper presents a new model of human population dynamics that can be embedded into ESMs (Earth System Models) to improve climate modeling. Through a system dynamics approach, we develop a cohort-component model that successfully simulates historical population dynamics with fine spatial resolution (about 1°×1°). The population projections are used to improve the estimates of CO 2 emissions, thus transcending the bulk approach of existing models and allowing more realistic non-linear effects to feature in the simulations. The module, dubbed POPEM (from Population Parameterization for Earth Models), is compared with current emission inventories and validated against UN aggregated data. Finally, it is shown that the module can be used to advance toward fully coupling the social and natural components of the Earth system, an emerging research path for environmental science and pollution research.
Polynomial algebra of discrete models in systems biology.
Veliz-Cuba, Alan; Jarrah, Abdul Salam; Laubenbacher, Reinhard
2010-07-01
An increasing number of discrete mathematical models are being published in Systems Biology, ranging from Boolean network models to logical models and Petri nets. They are used to model a variety of biochemical networks, such as metabolic networks, gene regulatory networks and signal transduction networks. There is increasing evidence that such models can capture key dynamic features of biological networks and can be used successfully for hypothesis generation. This article provides a unified framework that can aid the mathematical analysis of Boolean network models, logical models and Petri nets. They can be represented as polynomial dynamical systems, which allows the use of a variety of mathematical tools from computer algebra for their analysis. Algorithms are presented for the translation into polynomial dynamical systems. Examples are given of how polynomial algebra can be used for the model analysis. alanavc@vt.edu Supplementary data are available at Bioinformatics online.
Life Quality of Russian Immigrants to Israel: Patterns of Success and of Unsuccess
ERIC Educational Resources Information Center
Benish-Weisman, Maya; Shye, Samuel
2011-01-01
Two different perspectives on immigration outcomes are employed and interrelated: Overall assessments of the success in immigration and systemic quality of life assessments (using SQOL model, Shye in Soc Indic Res, 21:243-378, 1989). Data were collected from a sample of 337 immigrants to Israel from the former USSR. Results reveal that quality of…
A semi-Lagrangian advection scheme for radioactive tracers in a regional spectral model
NASA Astrophysics Data System (ADS)
Chang, E.-C.; Yoshimura, K.
2015-06-01
In this study, the non-iteration dimensional-split semi-Lagrangian (NDSL) advection scheme is applied to the National Centers for Environmental Prediction (NCEP) regional spectral model (RSM) to alleviate the Gibbs phenomenon. The Gibbs phenomenon is a problem wherein negative values of positive-definite quantities (e.g., moisture and tracers) are generated by the spectral space transformation in a spectral model system. To solve this problem, the spectral prognostic specific humidity and radioactive tracer advection scheme is replaced by the NDSL advection scheme, which considers advection of tracers in a grid system without spectral space transformations. A regional version of the NDSL is developed in this study and is applied to the RSM. Idealized experiments show that the regional version of the NDSL is successful. The model runs for an actual case study suggest that the NDSL can successfully advect radioactive tracers (iodine-131 and cesium-137) without noise from the Gibbs phenomenon. The NDSL can also remove negative specific humidity values produced in spectral calculations without losing detailed features.
Two-lattice models of trace element behavior: A response
NASA Astrophysics Data System (ADS)
Ellison, Adam J. G.; Hess, Paul C.
1990-08-01
Two-lattice melt components of Bottinga and Weill (1972), Nielsen and Drake (1979), and Nielsen (1985) are applied to major and trace element partitioning between coexisting immiscible liquids studied by RYERSON and Hess (1978) and Watson (1976). The results show that (1) the set of components most successful in one system is not necessarily portable to another system; (2) solution non-ideality within a sublattice severely limits applicability of two-lattice models; (3) rigorous application of two-lattice melt components may yield effective partition coefficients for major element components with no physical interpretation; and (4) the distinction between network-forming and network-modifying components in the sense of the two-lattice models is not clear cut. The algebraic description of two-lattice models is such that they will most successfully limit the compositional dependence of major and trace element solution behavior when the effective partition coefficient of the component of interest is essentially the same as the bulk partition coefficient of all other components within its sublattice.
Three Collaborative Models for Scaling Up Evidence-Based Practices
Roberts, Rosemarie; Jones, Helen; Marsenich, Lynne; Sosna, Todd; Price, Joseph M.
2015-01-01
The current paper describes three models of research-practice collaboration to scale-up evidence-based practices (EBP): (1) the Rolling Cohort model in England, (2) the Cascading Dissemination model in San Diego County, and (3) the Community Development Team model in 53 California and Ohio counties. Multidimensional Treatment Foster Care (MTFC) and KEEP are the focal evidence-based practices that are designed to improve outcomes for children and families in the child welfare, juvenile justice, and mental health systems. The three scale-up models each originated from collaboration between community partners and researchers with the shared goal of wide-spread implementation and sustainability of MTFC/KEEP. The three models were implemented in a variety of contexts; Rolling Cohort was implemented nationally, Cascading Dissemination was implemented within one county, and Community Development Team was targeted at the state level. The current paper presents an overview of the development of each model, the policy frameworks in which they are embedded, system challenges encountered during scale-up, and lessons learned. Common elements of successful scale-up efforts, barriers to success, factors relating to enduring practice relationships, and future research directions are discussed. PMID:21484449
Bi-directional transition nets
NASA Astrophysics Data System (ADS)
Staines, Anthony Spiteri
2017-06-01
Ordinary Petri nets are forward directed transition systems. Modern transition systems events and event flows are reversible. Hence modeling structures that reflect this are important. The creation of a bi-directional Petri net extends the modeling power of Petri nets. This work presents the successful implementation of a bi-directional transition net. Some toy examples in comparison to Petri nets are given showing the increased modeling power in a compacted form. The results show some interesting findings on how the expressive power of these structures has been increased.
Simic, Vladimir
2016-06-01
As the number of end-of-life vehicles (ELVs) is estimated to increase to 79.3 million units per year by 2020 (e.g., 40 million units were generated in 2010), there is strong motivation to effectively manage this fast-growing waste flow. Intensive work on management of ELVs is necessary in order to more successfully tackle this important environmental challenge. This paper proposes an interval-parameter chance-constraint programming model for end-of-life vehicles management under rigorous environmental regulations. The proposed model can incorporate various uncertainty information in the modeling process. The complex relationships between different ELV management sub-systems are successfully addressed. Particularly, the formulated model can help identify optimal patterns of procurement from multiple sources of ELV supply, production and inventory planning in multiple vehicle recycling factories, and allocation of sorted material flows to multiple final destinations under rigorous environmental regulations. A case study is conducted in order to demonstrate the potentials and applicability of the proposed model. Various constraint-violation probability levels are examined in detail. Influences of parameter uncertainty on model solutions are thoroughly investigated. Useful solutions for the management of ELVs are obtained under different probabilities of violating system constraints. The formulated model is able to tackle a hard, uncertainty existing ELV management problem. The presented model has advantages in providing bases for determining long-term ELV management plans with desired compromises between economic efficiency of vehicle recycling system and system-reliability considerations. The results are helpful for supporting generation and improvement of ELV management plans. Copyright © 2016 Elsevier Ltd. All rights reserved.
Report of the LSPI/NASA Workshop on Lunar Base Methodology Development
NASA Technical Reports Server (NTRS)
Nozette, Stewart; Roberts, Barney
1985-01-01
Groundwork was laid for computer models which will assist in the design of a manned lunar base. The models, herein described, will provide the following functions for the successful conclusion of that task: strategic planning; sensitivity analyses; impact analyses; and documentation. Topics addressed include: upper level model description; interrelationship matrix; user community; model features; model descriptions; system implementation; model management; and plans for future action.
NASA Technical Reports Server (NTRS)
1972-01-01
The detailed abort sequence trees for the reference zirconium hydride (ZrH) reactor power module that have been generated for each phase of the reference Space Base program mission are presented. The trees are graphical representations of causal sequences. Each tree begins with the phase identification and the dichotomy between success and failure. The success branch shows the mission phase objective as being achieved. The failure branch is subdivided, as conditions require, into various primary initiating abort conditions.
Component-Oriented Behavior Extraction for Autonomic System Design
NASA Technical Reports Server (NTRS)
Bakera, Marco; Wagner, Christian; Margaria,Tiziana; Hinchey, Mike; Vassev, Emil; Steffen, Bernhard
2009-01-01
Rich and multifaceted domain specific specification languages like the Autonomic System Specification Language (ASSL) help to design reliable systems with self-healing capabilities. The GEAR game-based Model Checker has been used successfully to investigate properties of the ESA Exo- Mars Rover in depth. We show here how to enable GEAR s game-based verification techniques for ASSL via systematic model extraction from a behavioral subset of the language, and illustrate it on a description of the Voyager II space mission.
A Goal Seeking Strategy for Constructing Systems from Alternative Components
NASA Technical Reports Server (NTRS)
Valentine, Mark E.
1999-01-01
This paper describes a methodology to efficiently construct feasible systems then modify feasible systems to meet successive goals by selecting from alternative components, a problem recognized to be n-p complete. The methodology provides a means to catalog and model alternative components. A presented system modeling Structure is robust enough to model a wide variety of systems and provides a means to compare and evaluate alternative systems. These models act as input to a methodology for selecting alternative components to construct feasible systems and modify feasible systems to meet design goals and objectives. The presented algorithm's ability to find a restricted solution, as defined by a unique set of requirements, is demonstrated against an exhaustive search of a sample of proposed shuttle modifications. The utility of the algorithm is demonstrated by comparing results from the algorithm with results from three NASA shuttle evolution studies using their value systems and assumptions.
VEGA, the European small launcher: Development status, future perspectives, and applications
NASA Astrophysics Data System (ADS)
Bianchi, Stefano; VEGA Integrated Project Team (IPT)
2008-07-01
This paper presents a technical and programmatic overview of the VEGA launch system program currently in development for the European Space Agency, which includes the development and qualification activities of the small launcher VEGA, of the ground infrastructure, and of all the launcher elements. Several programmatic milestones have been successfully achieved so far: most subsystems have gone through the critical design review or qualification review. The launcher system critical design review has been performed during spring 2007 as well. Concerning propulsion, all the three development models of the solid rocket motors have been successfully tested between December 2005 and December 2006. The first qualification model engine of the liquid propulsion upper module has successfully completed its firing campaign and the test campaign for the second model has just started. The liquid upper stage AVUM engine has been tested as well. The VEGA ground segment program has entered its final lapse by completing the detailed design of the various subsystems. The installation phase in the launch range site (Kourou, French Guyane) is in full swing. The integration of the Mobile Gantry, necessary to integrate the launcher, is almost completed as for the main structure.
Financial and economic determinants of collective action: The case of wastewater management
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brunner, Norbert, E-mail: norbert.brunner@cemds.org; Starkl, Markus, E-mail: markus.starkl@boku.ac.at
Where public environmental funds support development of wastewater infrastructure, funding institutions ensure the economic use of funds, while the beneficiaries minimize their own costs. In rural areas, there is often a choice between decentralized or centralized (multi-village) systems: if the centralized system is most economic, then only this system is eligible for public funding. However, its implementation requires a voluntary cooperation of the concerned communities, who need to organize themselves to develop and run the infrastructure. The paper analyzes the social determinants of collaboration in a generic case study, using the following variables: method of (economic) assessment, modeled by themore » social discount rate, funding policy, modeled by the funding rate, and users' self-organization, modeled by cost sharing. In a borderline situation, where the centralized system turns out to be most economic, but this assessment is contingent on the assessment method, collective action may fail: the advantages of collective action from funding are too small to outweigh organizational deficiencies. Considering in this situation sanitation as a human right, authors recommend using innovative forms of organization and, if these fail, reassessing either the amount of funding or the eligibility for funding of more acceptable alternatives. - Highlights: Black-Right-Pointing-Pointer A generic case study models collective action and funding in wastewater management. Black-Right-Pointing-Pointer Determinants of success: economic assessment, funding policy and self-organization. Black-Right-Pointing-Pointer Success indicators: conflict rate, funds needed to make cost shares fair. Black-Right-Pointing-Pointer Method for analyzing centralized vs. decentralized disputes. Black-Right-Pointing-Pointer If collective action has less benefits, innovative cost sharing may ensure success.« less
The intellectual core of enterprise information systems: a co-citation analysis
NASA Astrophysics Data System (ADS)
Shiau, Wen-Lung
2016-10-01
Enterprise information systems (EISs) have evolved in the past 20 years, attracting the attention of international practitioners and scholars. Although literature reviews and analyses have been conducted to examine the multiple dimensions of EISs, no co-citation analysis has been conducted to examine the knowledge structures involved in EIS studies; thus, the current study fills this research gap. This study investigated the intellectual structures of EISs. All data source documents (1083 articles and 24,090 citations) were obtained from the Institute for Scientific Information Web of Knowledge database. A co-citation analysis was used to analyse EIS data. By using factor analysis, we identified eight critical factors: (a) factors affecting the implementation and success of information systems (ISs); (b) the successful implementation of enterprise resource planning (ERP); (c) IS evaluation and success, (d) system science studies; (e) factors influencing ERP success; (f) case research and theoretical models; (g) user acceptance of information technology; and (h) IS frameworks. Multidimensional scaling and cluster analysis were used to visually map the resultant EIS knowledge. It is difficult to implement an EIS in an enterprise and each organisation exhibits specific considerations. The current findings indicate that managers must focus on ameliorating inferior project performance levels, enabling a transition from 'vicious' to 'virtuous' projects. Successful EIS implementation yields substantial organisational advantages.
Challenges in the development of chronic pulmonary hypertension models in large animals
Rothman, Abraham; Wiencek, Robert G.; Davidson, Stephanie; Evans, William N.; Restrepo, Humberto; Sarukhanov, Valeri; Mann, David
2017-01-01
Pulmonary hypertension (PH) results in significant morbidity and mortality. Chronic PH animal models may advance the study of PH’s mechanisms, evolution, and therapy. In this report, we describe the challenges and successes in developing three models of chronic PH in large animals: two models (one canine and one swine) utilized repeated infusions of ceramic microspheres into the pulmonary vascular bed, and the third model employed a surgical aorto-pulmonary shunt. In the canine model, seven dogs underwent microsphere infusions that resulted in progressive elevation of pulmonary arterial pressure over a few months. In this model, pulmonary endoarterial tissue was obtained for histology. In the aorto-pulmonary shunt swine model, 17 pigs developed systemic level pulmonary pressures after 2–3 months. In this model, pulmonary endoarterial tissue was sequentially obtained to assess for changes in gene and microRNA expression. In the swine microsphere infusion model, three pigs developed only a modest chronic increase in pulmonary arterial pressure, despite repeated infusions of microspheres (up to 40 in one animal). The main purpose of this model was for vasodilator testing, which was performed successfully immediately after acute microsphere infusions. Chronic PH in large animal models can be successfully created; however, a model’s characteristics need to match the investigational goals. PMID:28680575
Adaptive Modeling of the International Space Station Electrical Power System
NASA Technical Reports Server (NTRS)
Thomas, Justin Ray
2007-01-01
Software simulations provide NASA engineers the ability to experiment with spacecraft systems in a computer-imitated environment. Engineers currently develop software models that encapsulate spacecraft system behavior. These models can be inaccurate due to invalid assumptions, erroneous operation, or system evolution. Increasing accuracy requires manual calibration and domain-specific knowledge. This thesis presents a method for automatically learning system models without any assumptions regarding system behavior. Data stream mining techniques are applied to learn models for critical portions of the International Space Station (ISS) Electrical Power System (EPS). We also explore a knowledge fusion approach that uses traditional engineered EPS models to supplement the learned models. We observed that these engineered EPS models provide useful background knowledge to reduce predictive error spikes when confronted with making predictions in situations that are quite different from the training scenarios used when learning the model. Evaluations using ISS sensor data and existing EPS models demonstrate the success of the adaptive approach. Our experimental results show that adaptive modeling provides reductions in model error anywhere from 80% to 96% over these existing models. Final discussions include impending use of adaptive modeling technology for ISS mission operations and the need for adaptive modeling in future NASA lunar and Martian exploration.
Carter, Evelene M; Potts, Henry W W
2014-04-04
To investigate whether factors can be identified that significantly affect hospital length of stay from those available in an electronic patient record system, using primary total knee replacements as an example. To investigate whether a model can be produced to predict the length of stay based on these factors to help resource planning and patient expectations on their length of stay. Data were extracted from the electronic patient record system for discharges from primary total knee operations from January 2007 to December 2011 (n=2,130) at one UK hospital and analysed for their effect on length of stay using Mann-Whitney and Kruskal-Wallis tests for discrete data and Spearman's correlation coefficient for continuous data. Models for predicting length of stay for primary total knee replacements were tested using the Poisson regression and the negative binomial modelling techniques. Factors found to have a significant effect on length of stay were age, gender, consultant, discharge destination, deprivation and ethnicity. Applying a negative binomial model to these variables was successful. The model predicted the length of stay of those patients who stayed 4-6 days (~50% of admissions) with 75% accuracy within 2 days (model data). Overall, the model predicted the total days stayed over 5 years to be only 88 days more than actual, a 6.9% uplift (test data). Valuable information can be found about length of stay from the analysis of variables easily extracted from an electronic patient record system. Models can be successfully created to help improve resource planning and from which a simple decision support system can be produced to help patient expectation on their length of stay.
Results from a workshop on research needs for modeling aquifer thermal energy storage systems
NASA Astrophysics Data System (ADS)
Drost, M. K.
1990-08-01
A workshop an aquifer thermal energy storage (ATES) system modeling was conducted by Pacific Northwest Laboratory (PNL). The goal of the workshop was to develop a list of high priority research activities that would facilitate the commercial success of ATES. During the workshop, participants reviewed currently available modeling tools for ATES systems and produced a list of significant issues related to modeling ATES systems. Participants assigned a priority to each issue on the list by voting and developed a list of research needs for each of four high-priority research areas; the need for a feasibility study model, the need for engineering design models, the need for aquifer characterization, and the need for an economic model. The workshop participants concluded that ATES commercialization can be accelerated by aggressive development of ATES modeling tools and made specific recommendations for that development.
Species traits and network structure predict the success and impacts of pollinator invasions.
Valdovinos, Fernanda S; Berlow, Eric L; Moisset de Espanés, Pablo; Ramos-Jiliberto, Rodrigo; Vázquez, Diego P; Martinez, Neo D
2018-05-31
Species invasions constitute a major and poorly understood threat to plant-pollinator systems. General theory predicting which factors drive species invasion success and subsequent effects on native ecosystems is particularly lacking. We address this problem using a consumer-resource model of adaptive behavior and population dynamics to evaluate the invasion success of alien pollinators into plant-pollinator networks and their impact on native species. We introduce pollinator species with different foraging traits into network models with different levels of species richness, connectance, and nestedness. Among 31 factors tested, including network and alien properties, we find that aliens with high foraging efficiency are the most successful invaders. Networks exhibiting high alien-native diet overlap, fraction of alien-visited plant species, most-generalist plant connectivity, and number of specialist pollinator species are the most impacted by invaders. Our results mimic several disparate observations conducted in the field and potentially elucidate the mechanisms responsible for their variability.
Forecasting municipal solid waste generation using artificial intelligence modelling approaches.
Abbasi, Maryam; El Hanandeh, Ali
2016-10-01
Municipal solid waste (MSW) management is a major concern to local governments to protect human health, the environment and to preserve natural resources. The design and operation of an effective MSW management system requires accurate estimation of future waste generation quantities. The main objective of this study was to develop a model for accurate forecasting of MSW generation that helps waste related organizations to better design and operate effective MSW management systems. Four intelligent system algorithms including support vector machine (SVM), adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN) and k-nearest neighbours (kNN) were tested for their ability to predict monthly waste generation in the Logan City Council region in Queensland, Australia. Results showed artificial intelligence models have good prediction performance and could be successfully applied to establish municipal solid waste forecasting models. Using machine learning algorithms can reliably predict monthly MSW generation by training with waste generation time series. In addition, results suggest that ANFIS system produced the most accurate forecasts of the peaks while kNN was successful in predicting the monthly averages of waste quantities. Based on the results, the total annual MSW generated in Logan City will reach 9.4×10(7)kg by 2020 while the peak monthly waste will reach 9.37×10(6)kg. Copyright © 2016 Elsevier Ltd. All rights reserved.
The Virtual Extension Annual Conference: Addressing Contemporary Professional Development Needs
ERIC Educational Resources Information Center
Franz, Nancy K.; Brekke, Robin; Coates, Deb; Kress, Cathann; Hlas, Julie
2014-01-01
Extension systems are experimenting with new models for conducting professional development to enhance staff competence and other returns on professional development investments. The ISUEO virtual annual conference provides a successful flipped classroom model of asynchronous and synchronous learning events for conducting an Extension annual…
USDA-ARS?s Scientific Manuscript database
Successful hydrological model predictions depend on appropriate framing of scale and the spatial-temporal accuracy of input parameters describing soil hydraulic properties. Saturated soil hydraulic conductivity (Ksat) is one of the most important properties influencing water movement through soil un...
Towards General Models of Effective Science Inquiry in Virtual Performance Assessments
ERIC Educational Resources Information Center
Baker, R. S.; Clarke-Midura, J.; Ocumpaugh, J.
2016-01-01
Recent interest in online assessment of scientific inquiry has led to several new online systems that attempt to assess these skills, but producing models that detect when students are successfully practising these skills can be challenging. In this paper, we study models that assess student inquiry in an immersive virtual environment, where a…
NASA Astrophysics Data System (ADS)
Gajic, Gordana; Stankovski, Stevan; Ostojic, Gordana; Tesic, Zdravko; Miladinovic, Ljubomir
2014-01-01
The so far implemented enterprise resource planning (ERP) systems have in many cases failed to meet the requirements regarding the business process control, decrease of business costs and increase of company profit margin. Therefore, there is a real need for an evaluation of the influence of ERP on the company's performance indicators. Proposed in this article is an advanced model for the evaluation of the success of ERP implementation on organisational and operational performance indicators in oil-gas companies. The recommended method establishes a correlation between a process-based method, a scorecard model and ERP critical success factors. The method was verified and tested on two case studies in oil-gas companies using the following procedure: the model was developed, tested and implemented in a pilot gas-oil company, while the results were implemented and verified in another gas-oil company.
Successional dynamics drive tropical forest nutrient limitation
NASA Astrophysics Data System (ADS)
Chou, C.; Hedin, L. O. O.
2017-12-01
It is increasingly recognized that nutrients such as N and P may significantly constrain the land carbon sink. However, we currently lack a complete understanding of these nutrient cycles in forest ecosystems and how to incorporate them into Earth System Models. We have developed a framework of dynamic forest nutrient limitation, focusing on the role of secondary forest succession and canopy gap disturbances as bottlenecks of high plant nutrient demand and limitation. We used succession biomass data to parameterize a simple ecosystem model and examined the dynamics of nutrient limitation throughout tropical secondary forest succession. Due to the patterns of biomass recovery in secondary tropical forests, we found high nutrient demand from rapid biomass accumulation in the earliest years of succession. Depending on previous land use scenarios, soil nutrient availability may also be low in this time period. Coupled together, this is evidence that there may be high biomass nutrient limitation early in succession, which is partially met by abundant symbiotic nitrogen fixation from certain tree species. We predict a switch from nitrogen limitation in early succession to one of three conditions: (i) phosphorus only, (ii) phosphorus plus nitrogen, or (iii) phosphorus, nitrogen, plus light co-limitation. We will discuss the mechanisms that govern the exact trajectory of limitation as forests build biomass. In addition, we used our model to explore scenarios of tropical secondary forest impermanence and the impacts of these dynamics on ecosystem nutrient limitation. We found that secondary forest impermanence exacerbates nutrient limitation and the need for nitrogen fixation early in succession. Together, these results indicate that biomass recovery dynamics early in succession as well as their connection to nutrient demand and limitation are fundamental for understanding and modeling nutrient limitation of the tropical forest carbon sink.
NASA Technical Reports Server (NTRS)
Denning, Peter J.
1990-01-01
Although powerful computers have allowed complex physical and manmade hardware systems to be modeled successfully, we have encountered persistent problems with the reliability of computer models for systems involving human learning, human action, and human organizations. This is not a misfortune; unlike physical and manmade systems, human systems do not operate under a fixed set of laws. The rules governing the actions allowable in the system can be changed without warning at any moment, and can evolve over time. That the governing laws are inherently unpredictable raises serious questions about the reliability of models when applied to human situations. In these domains, computers are better used, not for prediction and planning, but for aiding humans. Examples are systems that help humans speculate about possible futures, offer advice about possible actions in a domain, systems that gather information from the networks, and systems that track and support work flows in organizations.
Competitive assessment of aerospace systems using system dynamics
NASA Astrophysics Data System (ADS)
Pfaender, Jens Holger
Aircraft design has recently experienced a trend away from performance centric design towards a more balanced approach with increased emphasis on engineering an economically successful system. This approach focuses on bringing forward a comprehensive economic and life-cycle cost analysis. Since the success of any system also depends on many external factors outside of the control of the designer, this traditionally has been modeled as noise affecting the uncertainty of the design. However, this approach is currently lacking a strategic treatment of necessary early decisions affecting the probability of success of a given concept in a dynamic environment. This suggests that the introduction of a dynamic method into a life-cycle cost analysis should allow the analysis of the future attractiveness of such a concept in the presence of uncertainty. One way of addressing this is through the use of a competitive market model. However, existing market models do not focus on the dynamics of the market. Instead, they focus on modeling and predicting market share through logit regression models. The resulting models exhibit relatively poor predictive capabilities. The method proposed here focuses on a top-down approach that integrates a competitive model based on work in the field of system dynamics into the aircraft design process. Demonstrating such integration is one of the primary contributions of this work, which previously has not been demonstrated. This integration is achieved through the use of surrogate models, in this case neural networks. This enabled not only the practical integration of analysis techniques, but also reduced the computational requirements so that interactive exploration as envisioned was actually possible. The example demonstration of this integration is built on the competition in the 250 seat large commercial aircraft market exemplified by the Boeing 767-400ER and the Airbus A330-200. Both aircraft models were calibrated to existing performance and certification data and then integrated into the system dynamics market model. The market model was then calibrated with historical market data. This calibration showed a much improved predictive capability as compared to the conventional logit regression models. An additional advantage of this dynamic model is that to realize this improved capability, no additional explanatory variables were required. Furthermore, the resulting market model was then integrated into a prediction profiler environment with a time variant Monte-Carlo analysis resulting in a unique trade-off environment. This environment was shown to allow interactive trade-off between aircraft design decisions and economic considerations while allowing the exploration potential market success in the light of varying external market conditions and scenarios. The resulting method is capable of reduced decision support uncertainty and identification of robust design decisions in future scenarios with a high likelihood of occurrence with special focus on the path dependent nature of future implications of decisions. Furthermore, it was possible to demonstrate the increased importance of design and technology choices on the competitiveness in scenarios with drastic increases in commodity prices during the time period modeled. Another use of the existing outputs of the Monte-Carlo analysis was then realized by showing them on a multivariate scatter plot. This plot was then shown to enable by appropriate grouping of variables to enable the top down definition of an aircraft design, also known as inverse design. In other words this enables the designer to define strategic market and return on investment goals for a number of scenarios, for example the development of fuel prices, and then directly see which specific aircraft designs meet these goals.
Modeling and Analysis of the Reverse Water Gas Shift Process for In-Situ Propellant Production
NASA Technical Reports Server (NTRS)
Whitlow, Jonathan E.
2000-01-01
This report focuses on the development of mathematical models and simulation tools developed for the Reverse Water Gas Shift (RWGS) process. This process is a candidate technology for oxygen production on Mars under the In-Situ Propellant Production (ISPP) project. An analysis of the RWGS process was performed using a material balance for the system. The material balance is very complex due to the downstream separations and subsequent recycle inherent with the process. A numerical simulation was developed for the RWGS process to provide a tool for analysis and optimization of experimental hardware, which will be constructed later this year at Kennedy Space Center (KSC). Attempts to solve the material balance for the system, which can be defined by 27 nonlinear equations, initially failed. A convergence scheme was developed which led to successful solution of the material balance, however the simplified equations used for the gas separation membrane were found insufficient. Additional more rigorous models were successfully developed and solved for the membrane separation. Sample results from these models are included in this report, with recommendations for experimental work needed for model validation.
Family Health Conversations: How Do They Support Health?
Benzein, Eva
2014-01-01
Research shows that living with illness can be a distressing experience for the family and may result in suffering and reduced health. To meet families' needs, family systems intervention models are developed and employed in clinical contexts. For successful refinement and implementation it is important to understand how these models work. The aim of this study was therefore to describe the dialogue process and possible working mechanisms of one systems nursing intervention model, the Family Health Conversation model. A descriptive evaluation design was applied and 15 transcribed conversations with five families were analyzed within a hermeneutic tradition. Two types of interrelated dialogue events were identified: narrating and exploring. There was a flow between these events, a movement that was generated by the interaction between the participants. Our theoretically grounded interpretation showed that narrating, listening, and reconsidering in interaction may be understood as supporting family health by offering the families the opportunity to constitute self-identity and identity within the family, increasing the families' understanding of multiple ways of being and acting, to see new possibilities and to develop meaning and hope. Results from this study may hopefully contribute to the successful implementation of family systems interventions in education and clinical praxis. PMID:24800068
The Challenge and Opportunity of Parental Involvement in Juvenile Justice Services.
Burke, Jeffrey D; Mulvey, Edward P; Schubert, Carol A; Garbin, Sara R
2014-04-01
The active involvement of parents - whether as recipients, extenders, or managers of services - during their youth's experience with the juvenile justice system is widely assumed to be crucial. Parents and family advocacy groups note persisting concerns with the degree to which successful parental involvement is achieved. Justice system providers are highly motivated and actively working to make improvements. These coalescing interests provide a strong motivation for innovation and improvement regarding family involvement, but the likely success of these efforts is severely limited by the absence of any detailed definition of parental involvement or validated measure of this construct. Determining whether and how parental involvement works in juvenile justice services depends on the development of clear models and sound measurement. Efforts in other child serving systems offer guidance to achieve this goal. A multidimensional working model developed with parents involved in child protective services is presented as a template for developing a model for parental involvement in juvenile justice. Features of the model requiring changes to make it more adaptable to juvenile justice are identified. A systematic research agenda for developing methods and measures to meet the present demands for enhanced parental involvement in juvenile justice services is presented.
Booth, Richard G
2012-06-01
In this review, studies examining information and communication technology used by nurses in clinical practice were examined. Overall, a total of 39 studies were assessed spanning a time period from 1995 to 2008. The impacts of the various health information and communication technology evaluated by individual studies were synthesized using the DeLone and McLean's six-dimensional framework for evaluating information systems success (ie, System Quality, Information Quality, Service Quality, Use, User Satisfaction, and Net Benefits). Overall, the majority of researchers reported results related to the overall Net Benefits (positive, negative, and indifferent) of the health information and communication technology used by nurses. Attitudes and user satisfaction with technology were also commonly measured attributes. The current iteration of DeLone and McLean model is effective at synthesizing basic elements of health information and communication technology use by nurses. Regardless, the current model lacks the sociotechnical sensitivity to capture deeper nurse-technology relationalities. Limitations and recommendations are provided for researchers considering using the DeLone and McLean model for evaluating health information and communication technology used by nurses.
The Challenge and Opportunity of Parental Involvement in Juvenile Justice Services
Burke, Jeffrey D.; Mulvey, Edward P.; Schubert, Carol A.; Garbin, Sara R.
2014-01-01
The active involvement of parents – whether as recipients, extenders, or managers of services - during their youth’s experience with the juvenile justice system is widely assumed to be crucial. Parents and family advocacy groups note persisting concerns with the degree to which successful parental involvement is achieved. Justice system providers are highly motivated and actively working to make improvements. These coalescing interests provide a strong motivation for innovation and improvement regarding family involvement, but the likely success of these efforts is severely limited by the absence of any detailed definition of parental involvement or validated measure of this construct. Determining whether and how parental involvement works in juvenile justice services depends on the development of clear models and sound measurement. Efforts in other child serving systems offer guidance to achieve this goal. A multidimensional working model developed with parents involved in child protective services is presented as a template for developing a model for parental involvement in juvenile justice. Features of the model requiring changes to make it more adaptable to juvenile justice are identified. A systematic research agenda for developing methods and measures to meet the present demands for enhanced parental involvement in juvenile justice services is presented. PMID:24748704
NASA Astrophysics Data System (ADS)
Barros, Ana; Ager, Alan; Preisler, Haiganoush; Day, Michelle; Spies, Tom; Bolte, John
2015-04-01
Agent-based models (ABM) allow users to examine the long-term effects of agent decisions in complex systems where multiple agents and processes interact. This framework has potential application to study the dynamics of coupled natural and human systems where multiple stimuli determine trajectories over both space and time. We used Envision, a landscape based ABM, to analyze long-term wildfire dynamics in a heterogeneous, multi-owner landscape in Oregon, USA. Landscape dynamics are affected by land management policies, actors decisions, and autonomous processes such as vegetation succession, wildfire, or at a broader scale, climate change. Key questions include: 1) How are landscape dynamics influenced by policies and institutions, and 2) How do land management policies and actor decisions interact to produce intended and unintended consequences with respect to wildfire on fire-prone landscapes. Applying Envision to address these questions required the development of a wildfire module that could accurately simulate wildfires on the heterogeneous landscapes within the study area in terms of replicating historical fire size distribution, spatial distribution and fire intensity. In this paper we describe the development and testing of a mechanistic fire simulation system within Envision and application of the model on a 3.2 million fire prone landscape in central Oregon USA. The core fire spread equations use the Minimum Travel Time algorithm developed by M Finney. The model operates on a daily time step and uses a fire prediction system based on the relationship between energy release component and historical fires. Specifically, daily wildfire probabilities and sizes are generated from statistical analyses of historical fires in relation to daily ERC values. The MTT was coupled with the vegetation dynamics module in Envision to allow communication between the respective subsystem and effectively model fire effects and vegetation dynamics after a wildfire. Canopy and surface fuels are modeled in a state and transition framework that accounts for succession, fire effects, and fuels management. Fire effects are modeled using simulated fire intensity (flame length) to calculate expected vegetation impacts for each vegetation state. This talk will describe the mechanics of the simulation system along with initial results of Envision simulations for the Central Oregon study area that explore the dynamics of wildfire, fuel management, and succession over time.
McCarty, Elizabeth; Morress, Claire
2009-08-01
Children with a diagnosis of cerebral palsy often have significant physical limitations that prevent exploration and full participation in the environment. Assistive technology systems can provide opportunities for children with physical limitations to interact with their world, enabling play, communication, and daily living skills. Efficient access to and control of the technology is critical for successful use; however, establishing consistent access is often difficult because of the nature of the movement patterns exhibited by children with cerebral palsy. This article describes a 3-phase model of evaluation and intervention developed and used by Assistive Technology Services at the Aaron W. Perlman Center, Cincinnati Children's Hospital Medical Center, to establish successful access to technology systems in children with cerebral palsy.
Modeling of enterprise information systems implementation: a preliminary investigation
NASA Astrophysics Data System (ADS)
Yusuf, Yahaya Y.; Abthorpe, M. S.; Gunasekaran, Angappa; Al-Dabass, D.; Onuh, Spencer
2001-10-01
The business enterprise has never been in greater need of Agility and the current trend will continue unabated well into the future. It is now recognized that information system is both the foundation and a necessary condition for increased responsiveness. A successful implementation of Enterprise Resource Planning (ERP) can help a company to move towards delivering on its competitive objectives as it enables suppliers to reach out to customers beyond the borders of traditional market defined by geography. The cost of implementation, even when it is successful, could be significant. Bearing in mind the potential strategic benefits, it is important that the implementation project is managed effectively. To this end a project cost model against which to benchmark ongoing project expenditure versus activities completed has been proposed in this paper.
Mathematical modeling of the female reproductive system: from oocyte to delivery.
Clark, Alys R; Kruger, Jennifer A
2017-01-01
From ovulation to delivery, and through the menstrual cycle, the female reproductive system undergoes many dynamic changes to provide an optimal environment for the embryo to implant, and to develop successfully. It is difficult ethically and practically to observe the system over the timescales involved in growth and development (often hours to days). Even in carefully monitored conditions clinicians and biologists can only see snapshots of the development process. Mathematical models are emerging as a key means to supplement our knowledge of the reproductive process, and to tease apart complexity in the reproductive system. These models have been used successfully to test existing hypotheses regarding the mechanisms of female infertility and pathological fetal development, and also to provide new experimentally testable hypotheses regarding the process of development. This new knowledge has allowed for improvements in assisted reproductive technologies and is moving toward translation to clinical practice via multiscale assessments of the dynamics of ovulation, development in pregnancy, and the timing and mechanics of delivery. WIREs Syst Biol Med 2017, 9:e1353. doi: 10.1002/wsbm.1353 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.
Stochastic geometry in disordered systems, applications to quantum Hall transitions
NASA Astrophysics Data System (ADS)
Gruzberg, Ilya
2012-02-01
A spectacular success in the study of random fractal clusters and their boundaries in statistical mechanics systems at or near criticality using Schramm-Loewner Evolutions (SLE) naturally calls for extensions in various directions. Can this success be repeated for disordered and/or non-equilibrium systems? Naively, when one thinks about disordered systems and their average correlation functions one of the very basic assumptions of SLE, the so called domain Markov property, is lost. Also, in some lattice models of Anderson transitions (the network models) there are no natural clusters to consider. Nevertheless, in this talk I will argue that one can apply the so called conformal restriction, a notion of stochastic conformal geometry closely related to SLE, to study the integer quantum Hall transition and its variants. I will focus on the Chalker-Coddington network model and will demonstrate that its average transport properties can be mapped to a classical problem where the basic objects are geometric shapes (loosely speaking, the current paths) that obey an important restriction property. At the transition point this allows to use the theory of conformal restriction to derive exact expressions for point contact conductances in the presence of various non-trivial boundary conditions.
Smith, Naomi; Barnes, Marian
2013-01-01
The Partnerships for Older People Projects programme provided government funding for local and health authorities to pilot prevention and intervention services in partnership with the voluntary sector and older people between 2006 and 2009. This local evaluation of a pilot in southern England undertaken between 2007 and 2009 used a Theory of Change approach to gathering and reflecting on data with different groups involved in the delivery of this whole-system based model of prevention. The model was delivered in the same way in seven social services locality areas within a large county authority. The method of data gathering enabled structured reflection on the implementation, development and projected outcomes of the model and a consideration of the key learning of working in a whole-system way with partners and stakeholders. The whole-system model, although complex and challenging to implement, was considered overall to have been a success and provided significant learning for partners and stakeholders on the challenges and benefits of working across professional and sectoral boundaries. New posts were created as part of the model. Two of these, recruited to and managed by voluntary sector partners, were identified as 'new jobs', but echoed 'old roles' within community and voluntary sector based health and social care. The authors reflect on the parallels of these roles with previously existing roles and ways of working and reflect on how the whole-system approach of this particular pilot enabled these new jobs to develop in particularly appropriate and successful ways. © 2012 Blackwell Publishing Ltd.
Designing To Learn about Complex Systems.
ERIC Educational Resources Information Center
Hmelo, Cindy E.; Holton, Douglas L.; Kolodner, Janet L.
2000-01-01
Indicates the presence of complex structural, behavioral, and functional relations to understanding. Reports on a design experiment in which 6th grade children learned about the human respiratory system by designing artificial lungs and building partial working models. Makes suggestions for successful learning from design activities. (Contains 44…
Automated System Checkout to Support Predictive Maintenance for the Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Patterson-Hine, Ann; Deb, Somnath; Kulkarni, Deepak; Wang, Yao; Lau, Sonie (Technical Monitor)
1998-01-01
The Propulsion Checkout and Control System (PCCS) is a predictive maintenance software system. The real-time checkout procedures and diagnostics are designed to detect components that need maintenance based on their condition, rather than using more conventional approaches such as scheduled or reliability centered maintenance. Predictive maintenance can reduce turn-around time and cost and increase safety as compared to conventional maintenance approaches. Real-time sensor validation, limit checking, statistical anomaly detection, and failure prediction based on simulation models are employed. Multi-signal models, useful for testability analysis during system design, are used during the operational phase to detect and isolate degraded or failed components. The TEAMS-RT real-time diagnostic engine was developed to utilize the multi-signal models by Qualtech Systems, Inc. Capability of predicting the maintenance condition was successfully demonstrated with a variety of data, from simulation to actual operation on the Integrated Propulsion Technology Demonstrator (IPTD) at Marshall Space Flight Center (MSFC). Playback of IPTD valve actuations for feature recognition updates identified an otherwise undetectable Main Propulsion System 12 inch prevalve degradation. The algorithms were loaded into the Propulsion Checkout and Control System for further development and are the first known application of predictive Integrated Vehicle Health Management to an operational cryogenic testbed. The software performed successfully in real-time, meeting the required performance goal of 1 second cycle time.
Liao, Chen; Seo, Seung-Oh; Celik, Venhar; Liu, Huaiwei; Kong, Wentao; Wang, Yi; Blaschek, Hans; Jin, Yong-Su; Lu, Ting
2015-07-07
Microbial metabolism involves complex, system-level processes implemented via the orchestration of metabolic reactions, gene regulation, and environmental cues. One canonical example of such processes is acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum, during which cells convert carbon sources to organic acids that are later reassimilated to produce solvents as a strategy for cellular survival. The complexity and systems nature of the process have been largely underappreciated, rendering challenges in understanding and optimizing solvent production. Here, we present a system-level computational framework for ABE fermentation that combines metabolic reactions, gene regulation, and environmental cues. We developed the framework by decomposing the entire system into three modules, building each module separately, and then assembling them back into an integrated system. During the model construction, a bottom-up approach was used to link molecular events at the single-cell level into the events at the population level. The integrated model was able to successfully reproduce ABE fermentations of the WT C. acetobutylicum (ATCC 824), as well as its mutants, using data obtained from our own experiments and from literature. Furthermore, the model confers successful predictions of the fermentations with various network perturbations across metabolic, genetic, and environmental aspects. From foundation to applications, the framework advances our understanding of complex clostridial metabolism and physiology and also facilitates the development of systems engineering strategies for the production of advanced biofuels.
Liao, Chen; Seo, Seung-Oh; Celik, Venhar; Liu, Huaiwei; Kong, Wentao; Wang, Yi; Blaschek, Hans; Jin, Yong-Su; Lu, Ting
2015-01-01
Microbial metabolism involves complex, system-level processes implemented via the orchestration of metabolic reactions, gene regulation, and environmental cues. One canonical example of such processes is acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum, during which cells convert carbon sources to organic acids that are later reassimilated to produce solvents as a strategy for cellular survival. The complexity and systems nature of the process have been largely underappreciated, rendering challenges in understanding and optimizing solvent production. Here, we present a system-level computational framework for ABE fermentation that combines metabolic reactions, gene regulation, and environmental cues. We developed the framework by decomposing the entire system into three modules, building each module separately, and then assembling them back into an integrated system. During the model construction, a bottom-up approach was used to link molecular events at the single-cell level into the events at the population level. The integrated model was able to successfully reproduce ABE fermentations of the WT C. acetobutylicum (ATCC 824), as well as its mutants, using data obtained from our own experiments and from literature. Furthermore, the model confers successful predictions of the fermentations with various network perturbations across metabolic, genetic, and environmental aspects. From foundation to applications, the framework advances our understanding of complex clostridial metabolism and physiology and also facilitates the development of systems engineering strategies for the production of advanced biofuels. PMID:26100881
Kaplan, Heather C; Brady, Patrick W; Dritz, Michele C; Hooper, David K; Linam, W Matthew; Froehle, Craig M; Margolis, Peter
2010-01-01
Context: The mixed results of success among QI initiatives may be due to differences in the context of these initiatives. Methods: The business and health care literature was systematically reviewed to identify contextual factors that might influence QI success; to categorize, summarize, and synthesize these factors; and to understand the current stage of development of this research field. Findings: Forty-seven articles were included in the final review. Consistent with current theories of implementation and organization change, leadership from top management, organizational culture, data infrastructure and information systems, and years involved in QI were suggested as important to QI success. Other potentially important factors identified in this review included: physician involvement in QI, microsystem motivation to change, resources for QI, and QI team leadership. Key limitations in the existing literature were the lack of a practical conceptual model, the lack of clear definitions of contextual factors, and the lack of well-specified measures. Conclusions: Several contextual factors were shown to be important to QI success, although the current body of literature lacks adequate definitions and is characterized by considerable variability in how contextual factors are measured across studies. Future research should focus on identifying and developing measures of context tied to a conceptual model that examines context across all levels of the health care system and explores the relationships among various aspects of context. PMID:21166868
Kaplan, Heather C; Brady, Patrick W; Dritz, Michele C; Hooper, David K; Linam, W Matthew; Froehle, Craig M; Margolis, Peter
2010-12-01
The mixed results of success among QI initiatives may be due to differences in the context of these initiatives. The business and health care literature was systematically reviewed to identify contextual factors that might influence QI success; to categorize, summarize, and synthesize these factors; and to understand the current stage of development of this research field. Forty-seven articles were included in the final review. Consistent with current theories of implementation and organization change, leadership from top management, organizational culture, data infrastructure and information systems, and years involved in QI were suggested as important to QI success. Other potentially important factors identified in this review included: physician involvement in QI, microsystem motivation to change, resources for QI, and QI team leadership. Key limitations in the existing literature were the lack of a practical conceptual model, the lack of clear definitions of contextual factors, and the lack of well-specified measures. Several contextual factors were shown to be important to QI success, although the current body of literature lacks adequate definitions and is characterized by considerable variability in how contextual factors are measured across studies. Future research should focus on identifying and developing measures of context tied to a conceptual model that examines context across all levels of the health care system and explores the relationships among various aspects of context. © 2010 Milbank Memorial Fund. Published by Wiley Periodicals Inc.
Development of techniques for processing metal-metal oxide systems
NASA Technical Reports Server (NTRS)
Johnson, P. C.
1976-01-01
Techniques for producing model metal-metal oxide systems for the purpose of evaluating the results of processing such systems in the low-gravity environment afforded by a drop tower facility are described. Because of the lack of success in producing suitable materials samples and techniques for processing in the 3.5 seconds available, the program was discontinued.
Distance Learning Success--A Perspective from Socio-Technical Systems Theory
ERIC Educational Resources Information Center
Wang, Jianfeng; Solan, David; Ghods, Abe
2010-01-01
With widespread adoption of computer-based distance education as a mission-critical component of the institution's educational program, the need for evaluation has emerged. In this research, we aim to expand on the systems approach by offering a model for evaluation based on socio-technical systems theory addressing a stated need in the literature…
ERIC Educational Resources Information Center
Ngafeeson, Madison N.
2013-01-01
The successful implementation of health information systems is expected to increase legibility, reduce medical errors, boost the quality of healthcare and shrink costs. Yet, evidence points to the fact that healthcare professionals resist the full use of these systems. Physicians and nurses have been reported to resist the system. Even though…
ERIC Educational Resources Information Center
Sager, Fritz
2008-01-01
The dual system of vocational training, utilising both company training and vocational school attendance, is generally acknowledged to be a successful model for reducing youth unemployment. However, the decreasing number of training opportunities in countries with this system poses a crisis for the approach. One strategy for overcoming the problem…
ERIC Educational Resources Information Center
Noltemeyer, Amity; Petrasek, Michael; Stine, Karen; Palmer, Katelyn; Meehan, Cricket; Jordan, Emily
2018-01-01
With the increasing use of Positive Behavioral Interventions and Supports (PBIS) nationally, several states have developed systems to recognize exemplar schools that are implementing PBIS with fidelity. These systems serve the dual purpose of identifying model PBIS schools for other schools to emulate while also reinforcing schools' effective PBIS…
Lawrence R. Walker; Aaron B. Shiels; Peter J. Bellingham; Ashley D. Sparrow; Ned Fetcher; Fred H. Landau; Deborah J. Lodge
2013-01-01
Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. In an 18-year...
ERIC Educational Resources Information Center
Petty, Norman H.; Todd, Anne
A project sought to identify variables that are associated with student success in allied health care programs in order to provide program directors with better admissions information. Forty-nine allied health programs provided data on over 1,800 students. One questionnaire generated these basic program data for each participating program: dropout…
NASA Technical Reports Server (NTRS)
Young, Clarence P., Jr.; Balakrishna, S.; Kilgore, W. Allen
1995-01-01
A state-of-the-art, computerized mode protection and dynamic response monitoring system has been developed for the NASA Langley Research Center National Transonic Facility (NTF). This report describes the development of the model protection and shutdown system (MPSS). A technical description of the system is given along with discussions on operation and capabilities of the system. Applications of the system to vibration problems are presented to demonstrate the system capabilities, typical applications, versatility, and investment research return derived from the system to date. The system was custom designed for the NTF but can be used at other facilities or for other dynamic measurement/diagnostic applications. Potential commercial uses of the system are described. System capability has been demonstrated for forced response testing and for characterizing and quantifying bias errors for onboard inertial model attitude measurement devices. The system is installed in the NTF control room and has been used successfully for monitoring, recording and analyzing the dynamic response of several model systems tested in the NTF.
Aeroservoelastic Testing of a Sidewall Mounted Free Flying Wind-Tunnel Model
NASA Technical Reports Server (NTRS)
Scott, Robert C.; Vetter, Travis K.; Penning, Kevin B.; Coulson, David A.; Heeg, Jennifer
2008-01-01
A team comprised of the Air Force Research Laboratory (AFRL), Northrop Grumman, Lockheed Martin, and the NASA Langley Research Center conducted three j wind-tunnel tests in the Transonic Dynamics Tunnel to demonstrate active control technologies relevant to large, exible vehicles. In the rst of these three tests, a semispan, aeroelastically scaled, wind-tunnel model of a ying wing SensorCraft vehi- cle was mounted to a force balance to demonstrate gust load alleviation. In the second and third tests, the same wing was mated to a new, multi-degree-of-freedom, sidewall mount. This mount allowed the half-span model to translate vertically and pitch at the wing root, allowing better simulation of the full span vehicle's rigid-body modes. Gust Load Alleviation (GLA) and Body Freedom Flutter (BFF) suppression were successfully demonstrated. The rigid body degrees-of-freedom required that the model be own in the wind tunnel using an active control system. This risky mode of testing necessitated that a model arrestment system be integrated into the new mount. The safe and successful completion of these free-flying tests required the development and integration of custom hardware and software. This paper describes the many systems, software, and procedures that were developed as part of this effort.
Adamusiak, Tomasz; Parkinson, Helen; Muilu, Juha; Roos, Erik; van der Velde, Kasper Joeri; Thorisson, Gudmundur A; Byrne, Myles; Pang, Chao; Gollapudi, Sirisha; Ferretti, Vincent; Hillege, Hans; Brookes, Anthony J; Swertz, Morris A
2012-05-01
Genetic and epidemiological research increasingly employs large collections of phenotypic and molecular observation data from high quality human and model organism samples. Standardization efforts have produced a few simple formats for exchange of these various data, but a lightweight and convenient data representation scheme for all data modalities does not exist, hindering successful data integration, such as assignment of mouse models to orphan diseases and phenotypic clustering for pathways. We report a unified system to integrate and compare observation data across experimental projects, disease databases, and clinical biobanks. The core object model (Observ-OM) comprises only four basic concepts to represent any kind of observation: Targets, Features, Protocols (and their Applications), and Values. An easy-to-use file format (Observ-TAB) employs Excel to represent individual and aggregate data in straightforward spreadsheets. The systems have been tested successfully on human biobank, genome-wide association studies, quantitative trait loci, model organism, and patient registry data using the MOLGENIS platform to quickly setup custom data portals. Our system will dramatically lower the barrier for future data sharing and facilitate integrated search across panels and species. All models, formats, documentation, and software are available for free and open source (LGPLv3) at http://www.observ-om.org. © 2012 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Lee, Allan Y.; Tsuha, Walter S.
1993-01-01
A two-stage model reduction methodology, combining the classical Component Mode Synthesis (CMS) method and the newly developed Enhanced Projection and Assembly (EP&A) method, is proposed in this research. The first stage of this methodology, called the COmponent Modes Projection and Assembly model REduction (COMPARE) method, involves the generation of CMS mode sets, such as the MacNeal-Rubin mode sets. These mode sets are then used to reduce the order of each component model in the Rayleigh-Ritz sense. The resultant component models are then combined to generate reduced-order system models at various system configurations. A composite mode set which retains important system modes at all system configurations is then selected from these reduced-order system models. In the second stage, the EP&A model reduction method is employed to reduce further the order of the system model generated in the first stage. The effectiveness of the COMPARE methodology has been successfully demonstrated on a high-order, finite-element model of the cruise-configured Galileo spacecraft.
NASA Astrophysics Data System (ADS)
Deese Becht, Sara-Maria Francis
1999-11-01
The purpose of this study is two-fold involving both practical and theoretical modeling components. The practical component, an experiential-learning phase, investigated a study population for effects that increasing levels of multicontextual physics activities have on student understanding of Newtonian systems of motion. This contextual-learning model measured learner convictions and non-response gaps and analyzed learner response trends on context, technology, challenge, growth, and success. The theoretical component, a model-building phase, designed a dynamic-knowing model for learning along a range of experiential tasks, from low to high context, monitored for indicators of learning in science and mathematics: learner academic performance and ability, learner control and academic attitude, and a learner non- response gap. This knowing model characterized a learner's process-of-knowing on a less to more expert- like learner-response continuum using performance and perspective indices associated with level of contextual- imagery referent system. Data for the contextual-learning model were collected on 180 secondary subjects: 72 middle and 108 high, with 36 physics subjects as local experts. Subjects were randomly assigned to one of three experimental groups differing only on context level of force and motion activities. Three levels of information were presented through context-based tasks: momentum constancy as inertia, momentum change as impulse, and momentum rate of change as force. The statistical analysis used a multi-level factorial design with repeated measures and discriminate analysis of response-conviction items. Subject grouping criteria included school level, ability level in science and mathematics, gender and race. Assessment criteria used pre/post performance scores, confidence level in physics concepts held, and attitude towards science, mathematics, and technology. Learner indices were computed from logit- transforms applied to learner outcomes and to study control and prediction criteria parameters. Findings suggest learner success rates vary with multicontextual experience level. When controlling for context, learner success seems to depend on technology level of assessment tool, learner attitude toward technology learning tools, learner attitude toward science and mathematics, and challenge level of force and motion problems. A learner non-response gap seems important when monitoring learner conviction. Application of the knowing model to the study population pictures learners on a journey towards success referenced to a local expert response.
Learning Physics-based Models in Hydrology under the Framework of Generative Adversarial Networks
NASA Astrophysics Data System (ADS)
Karpatne, A.; Kumar, V.
2017-12-01
Generative adversarial networks (GANs), that have been highly successful in a number of applications involving large volumes of labeled and unlabeled data such as computer vision, offer huge potential for modeling the dynamics of physical processes that have been traditionally studied using simulations of physics-based models. While conventional physics-based models use labeled samples of input/output variables for model calibration (estimating the right parametric forms of relationships between variables) or data assimilation (identifying the most likely sequence of system states in dynamical systems), there is a greater opportunity to explore the full power of machine learning (ML) methods (e.g, GANs) for studying physical processes currently suffering from large knowledge gaps, e.g. ground-water flow. However, success in this endeavor requires a principled way of combining the strengths of ML methods with physics-based numerical models that are founded on a wealth of scientific knowledge. This is especially important in scientific domains like hydrology where the number of data samples is small (relative to Internet-scale applications such as image recognition where machine learning methods has found great success), and the physical relationships are complex (high-dimensional) and non-stationary. We will present a series of methods for guiding the learning of GANs using physics-based models, e.g., by using the outputs of physics-based models as input data to the generator-learner framework, and by using physics-based models as generators trained using validation data in the adversarial learning framework. These methods are being developed under the broad paradigm of theory-guided data science that we are developing to integrate scientific knowledge with data science methods for accelerating scientific discovery.
Considering the difficulty in measuring restoration success for nonpoint source pollutants, nutrient assimilative capacity (NAS) offers an attractive systems-based metric. Here NAS was defined using an impulse-response model of nitrate fate and transport. Eleven parameters were e...
A hierarchical approach for simulating northern forest dynamics
Don C. Bragg; David W. Roberts; Thomas R. Crow
2004-01-01
Complexity in ecological systems has challenged forest simulation modelers for years, resulting in a number of approaches with varying degrees of success. Arguments in favor of hierarchical modeling are made, especially for considering a complex environmental issue like widespread eastern hemlock regeneration failure. We present the philosophy and basic framework for...
Models for At Risk Youth. Final Report.
ERIC Educational Resources Information Center
Woloszyk, Carl A.
Secondary data sources, including the ERIC and National Dropout Prevention Center databases, were reviewed to identify programs and strategies effective in keeping at-risk youth in school and helping them make successful school-to-work transitions. The dropout prevention model that was identified features a system of prevention, mediation,…
Developing Instructional Technology Products Using Effective Project Management Practices
ERIC Educational Resources Information Center
Allen, Stephanie; Hardin, Paul C.
2008-01-01
Delivering a successful instructional technology (IT) product depends on more than just having an extremely creative instructional solution or following an instructional systems design (ISD) model. Proper planning, direction, and execution of the project are require, as well. We present a model of management that encompasses the ISD process. Five…
ERIC Educational Resources Information Center
Reushle, Shirley, Ed.; Antonio, Amy, Ed.; Keppell, Mike, Ed.
2016-01-01
The discipline of education is a multi-faceted system that must constantly integrate new strategies and procedures to ensure successful learning experiences. Enhancements in education provide learners with greater opportunities for growth and advancement. "Open Learning and Formal Credentialing in Higher Education: Curriculum Models and…
Cooperative Teaching: A Model for Teacher Collaboration.
ERIC Educational Resources Information Center
Bohlmann, Natalie L.
1998-01-01
A third grade teacher examines the effects of cooperative teaching in a two-teacher classroom. After discussing teacher roles in such classrooms, the paper describes how the advantages of such a system greatly outweigh the disadvantages. The paper presents keys to a successful teaching partnership and describes several models for lesson…
Toluene, a solvent used in numerous consumer and industrial applications, exerts its critical effects on the brain and nervous system following inhalation exposure. Our previously published PBPK model successfully predicted toluene concentrations in blood and brain over a range o...
e-Learning Success Model: An Information Systems Perspective
ERIC Educational Resources Information Center
Lee-Post, Anita
2009-01-01
This paper reports the observations made and experience gained from developing and delivering an online quantitative methods course for Business undergraduates. Inspired by issues and challenges experienced in developing the online course, a model is advanced to address the question of how to guide the design, development, and delivery of…
Discrete dynamic modeling of cellular signaling networks.
Albert, Réka; Wang, Rui-Sheng
2009-01-01
Understanding signal transduction in cellular systems is a central issue in systems biology. Numerous experiments from different laboratories generate an abundance of individual components and causal interactions mediating environmental and developmental signals. However, for many signal transduction systems there is insufficient information on the overall structure and the molecular mechanisms involved in the signaling network. Moreover, lack of kinetic and temporal information makes it difficult to construct quantitative models of signal transduction pathways. Discrete dynamic modeling, combined with network analysis, provides an effective way to integrate fragmentary knowledge of regulatory interactions into a predictive mathematical model which is able to describe the time evolution of the system without the requirement for kinetic parameters. This chapter introduces the fundamental concepts of discrete dynamic modeling, particularly focusing on Boolean dynamic models. We describe this method step-by-step in the context of cellular signaling networks. Several variants of Boolean dynamic models including threshold Boolean networks and piecewise linear systems are also covered, followed by two examples of successful application of discrete dynamic modeling in cell biology.
Low GWP Refrigerants Modelling Study for a Room Air Conditioner Having Microchannel Heat Exchangers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Bo; Bhandari, Mahabir S
Microchannel heat exchangers (MHX) have found great successes in residential and commercial air conditioning applications, being compact heat exchangers, to reduce refrigerant charge and material cost. This investigation aims to extend the application of MHXs in split, room air conditioners (RAC), per fundamental heat exchanger and system modelling. For this paper, microchannel condenser and evaporator models were developed, using a segment-to-segment modelling approach. The microchannel heat exchanger models were integrated to a system design model. The system model is able to predict the performance indices, such as cooling capacity, efficiency, sensible heat ratio, etc. Using the calibrated system and heatmore » exchanger models, we evaluated numerous low GWP (global warming potential) refrigerants. The predicted system performance indices, e.g. cooling efficiency, compressor discharge temperature, and required compressor displacement volume etc., are compared. Suitable replacements for R22 and R-410A for the room air conditioner application are recommended.« less
Towards a Better Health Care Delivery System: The Tamil Nadu model.
Parthasarathi, R; Sinha, S P
2016-01-01
The Tamil Nadu model of public health is renowned for its success in providing quality health services at an affordable cost especially to the rural people. Tamil Nadu is the only state with a distinctive public health cadre in the district level and also the first state to enact a Public Health Act in 1939. Tamil Nadu has gained significant ground in the various aspects of health in the last few decades largely because of the significant reforms in its health sector which dates back to 1980s which saw rigorous expansion of rural health infrastructure in the state besides deployment of thousands of multipurpose health workers as village health nurses in rural areas. Effective implementation of Universal Immunization Programme, formation of Tamil Nadu Medical Services Corporation for regulating the drug procurement and promoting generic drugs, early incorporation of indigenous system of medicine into health care service, formulation of a health policy in 2003 by the state with special emphasis on low-income, disadvantaged communities alongside efficient implementation of The Tamil Nadu Health Systems Project (TNHSP) are the major factors which contributed for the success of the state. The importance of good political commitment and leadership in the health gains of the state warrants special mention. Moreover, the economic growth of the state, improved literacy rate, gender equality, and lowered fertility rate in the last few decades and contributions from the private sector have their share in the public health success of the state. In spite of some flaws and challenges, the Tamil Nadu Model remains the prototype health care delivery system in resource-limited settings which can be emulated by other states also toward a better health care delivery system.
Towards a Better Health Care Delivery System: The Tamil Nadu model
Parthasarathi, R.; Sinha, S.P.
2016-01-01
The Tamil Nadu model of public health is renowned for its success in providing quality health services at an affordable cost especially to the rural people. Tamil Nadu is the only state with a distinctive public health cadre in the district level and also the first state to enact a Public Health Act in 1939. Tamil Nadu has gained significant ground in the various aspects of health in the last few decades largely because of the significant reforms in its health sector which dates back to 1980s which saw rigorous expansion of rural health infrastructure in the state besides deployment of thousands of multipurpose health workers as village health nurses in rural areas. Effective implementation of Universal Immunization Programme, formation of Tamil Nadu Medical Services Corporation for regulating the drug procurement and promoting generic drugs, early incorporation of indigenous system of medicine into health care service, formulation of a health policy in 2003 by the state with special emphasis on low-income, disadvantaged communities alongside efficient implementation of The Tamil Nadu Health Systems Project (TNHSP) are the major factors which contributed for the success of the state. The importance of good political commitment and leadership in the health gains of the state warrants special mention. Moreover, the economic growth of the state, improved literacy rate, gender equality, and lowered fertility rate in the last few decades and contributions from the private sector have their share in the public health success of the state. In spite of some flaws and challenges, the Tamil Nadu Model remains the prototype health care delivery system in resource-limited settings which can be emulated by other states also toward a better health care delivery system. PMID:27890982
NASA Technical Reports Server (NTRS)
Thomas, Leann; Utley, Dawn
2006-01-01
While there has been extensive research in defining project organizational structures for traditional projects, little research exists to support high technology government project s organizational structure definition. High-Technology Government projects differ from traditional projects in that they are non-profit, span across Government-Industry organizations, typically require significant integration effort, and are strongly susceptible to a volatile external environment. Systems Integration implementation has been identified as a major contributor to both project success and failure. The literature research bridges program management organizational planning, systems integration, organizational theory, and independent project reports, in order to assess Systems Integration (SI) organizational structure selection for improving the high-technology government project s probability of success. This paper will describe the methodology used to 1) Identify and assess SI organizational structures and their success rate, and 2) Identify key factors to be used in the selection of these SI organizational structures during the acquisition strategy process.
Modeling and Analysis of Geoelectric Fields: Extended Solar Shield
NASA Astrophysics Data System (ADS)
Ngwira, C. M.; Pulkkinen, A. A.
2016-12-01
In the NASA Applied Sciences Program Solar Shield project, an unprecedented first-principles-based system to forecast geomagnetically induced current (GIC) in high-voltage power transmission systems was developed. Rapid progress in the field of numerical physics-based space environment modeling has led to major developments over the past few years. In this study modeling and analysis of induced geoelectric fields is discussed. Specifically, we focus on the successful incorporation of 3-D EM transfer functions in the modeling of E-fields, and on the analysis of near real-time simulation outputs used in the Solar Shield forecast system. The extended Solar Shield is a collaborative project between DHS, NASA, NOAA, CUA and EPRI.
Design and verification of distributed logic controllers with application of Petri nets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wiśniewski, Remigiusz; Grobelna, Iwona; Grobelny, Michał
2015-12-31
The paper deals with the designing and verification of distributed logic controllers. The control system is initially modelled with Petri nets and formally verified against structural and behavioral properties with the application of the temporal logic and model checking technique. After that it is decomposed into separate sequential automata that are working concurrently. Each of them is re-verified and if the validation is successful, the system can be finally implemented.
ERIC Educational Resources Information Center
Khotbancha, Wijitra; Chantarasombat, Chalard; Sriampai, Anan
2015-01-01
The objectives of this research were: 1) to study the current situation and problem of Knowledge Management of the office of the primary education service area, 2) to develop a Knowledge Management model, 3) to study the success of the implementation of the Knowledge Management system. There were 25 persons in the target group. There were 2 kinds…
Progress in Earth System Modeling since the ENIAC Calculation
NASA Astrophysics Data System (ADS)
Fung, I.
2009-05-01
The success of the first numerical weather prediction experiment on the ENIAC computer in 1950 was hinged on the expansion of the meteorological observing network, which led to theoretical advances in atmospheric dynamics and subsequently the implementation of the simplified equations on the computer. This paper briefly reviews the progress in Earth System Modeling and climate observations, and suggests a strategy to sustain and expand the observations needed to advance climate science and prediction.
Design and verification of distributed logic controllers with application of Petri nets
NASA Astrophysics Data System (ADS)
Wiśniewski, Remigiusz; Grobelna, Iwona; Grobelny, Michał; Wiśniewska, Monika
2015-12-01
The paper deals with the designing and verification of distributed logic controllers. The control system is initially modelled with Petri nets and formally verified against structural and behavioral properties with the application of the temporal logic and model checking technique. After that it is decomposed into separate sequential automata that are working concurrently. Each of them is re-verified and if the validation is successful, the system can be finally implemented.
Oxidation Mechanisms of Toluene and Benzene
NASA Technical Reports Server (NTRS)
Bittker, David A.
1995-01-01
An expanded and improved version of a previously published benzene oxidation mechanism is presented and shown to model published experimental data fairly successfully. This benzene submodel is coupled to a modified version of a toluene oxidation submodel from the recent literature. This complete mechanism is shown to successfully model published experimental toluene oxidation data for a highly mixed flow reactor and for higher temperature ignition delay times in a shock tube. A comprehensive sensitivity analysis showing the most important reactions is presented for both the benzene and toluene reacting systems. The NASA Lewis toluene mechanism's modeling capability is found to be equivalent to that of the previously published mechanism which contains a somewhat different benzene submodel.
NASA Astrophysics Data System (ADS)
Sivapalan, M.; Elshafei, Y.; Srinivasan, V.
2014-12-01
A challenging research puzzle in the research on sustainable water management in the Anthropocene is why some societies successfully recover from "ecological destruction" to transition to "successful adaptation" over decadal timescales, while others fail. We present a conceptual modeling framework to understand and characterize these transitions. In this way, we aim to capture the potential drivers of the desired shift towards achieving sustainability of socio-hydrological systems. This is done through a synthesis of detailed socio-hydrological analyses of four river basins in three continents, carried out using different quantitative socio-hydrologic models: Murrumbidgee River Basin in eastern Australia, Lake Toolibin Catchment in Western Australia, Tarim River Basin in Western China and Kissimmee River Basin, in south-east United States. The case studies are analysed using either place-based models designed specifically to mimic observed long-term socio-hydrologic trends, or generic conceptual models with foundations in diverse strands of literature including sustainability science and resilience theory. A comparative analysis of the four case studies reveals a commonality in the building blocks employed to model these socio-hydrologic systems; including water balance, economic, environmental and human-feedback components. Each model reveals varying interpretations of a common organising principle that could explain the shift between productive (socio-economic) and restorative (environmental) forces that was evident in each of these systems observed over a long time frame. The emergent principle is related to the essential drivers of the human feedback component and rests with a general formulation of human well-being, as reflected by both their economic and environmental well-being. It is envisaged that the understanding of the system drivers gained from such a comparative study would enable more targeted water management strategies that can be administered in developing basins to achieve overall sustainability.
Cheptou, P.-O.
2012-01-01
Background Baker's Law states that colonization by self-compatible organisms is more likely to be successful than colonization by self-incompatible organisms because of the ability for self-compatible organisms to produce offspring without pollination agents. This simple model has proved very successful in plant ecology and has been applied to various contexts, including colonizing or ruderal species, islands colonizers, invasive species or mating system variation across distribution ranges. Moreover, it is one of the only models in population biology linking two traits of major importance in ecology, namely dispersal and mating system. Although Baker's Law has stimulated a large number of empirical studies reporting the association of self-fertilization and colonizing ability in various contexts, the data have not established a general pattern for the association of traits. Scope In this paper, a critical position is adopted to discuss and clarify Baker's Law. From the literature referring to Baker's Law, an analysis made regarding how mating success is considered in such studies and discrepancies with population genetics theory of mating systems are highlighted. The data reporting the association of self-fertilization and colonizing ability are also briefly reviewed and the potential bias in interpretation is discussed. Lastly, a recent theoretical model analysing the link between colonizing ability and self-fertilization is considered. Conclusions Evolutionary predictions are actually more complex than Baker's intuitive arguments. It appears that Baker's Law encompasses a variety of ecological scenarios, which cannot be considered a priori as equivalent. Questioning what has been considered as self-evident for more than 50 years seems a reasonable objective to analyse in-depth dispersal and mating system traits. PMID:21685434
Voit, E O; Knapp, R G
1997-08-15
The linear-logistic regression model and Cox's proportional hazard model are widely used in epidemiology. Their successful application leaves no doubt that they are accurate reflections of observed disease processes and their associated risks or incidence rates. In spite of their prominence, it is not a priori evident why these models work. This article presents a derivation of the two models from the framework of canonical modeling. It begins with a general description of the dynamics between risk sources and disease development, formulates this description in the canonical representation of an S-system, and shows how the linear-logistic model and Cox's proportional hazard model follow naturally from this representation. The article interprets the model parameters in terms of epidemiological concepts as well as in terms of general systems theory and explains the assumptions and limitations generally accepted in the application of these epidemiological models.
Business model for sensor-based fall recognition systems.
Fachinger, Uwe; Schöpke, Birte
2014-01-01
AAL systems require, in addition to sophisticated and reliable technology, adequate business models for their launch and sustainable establishment. This paper presents the basic features of alternative business models for a sensor-based fall recognition system which was developed within the context of the "Lower Saxony Research Network Design of Environments for Ageing" (GAL). The models were developed parallel to the R&D process with successive adaptation and concretization. An overview of the basic features (i.e. nine partial models) of the business model is given and the mutual exclusive alternatives for each partial model are presented. The partial models are interconnected and the combinations of compatible alternatives lead to consistent alternative business models. However, in the current state, only initial concepts of alternative business models can be deduced. The next step will be to gather additional information to work out more detailed models.
ERIC Educational Resources Information Center
Tian-Ping, Yang
2012-01-01
Since implementation of reform and opening-up policy, China's teacher education has got significant success on policy design, legislation process, theory research, system reform, model innovation and teaching qualification system building. Teachers' educational background level has been increased. Teachers' professional ethics and teaching…
Locating Gender Bias and Systemic Discrimination in Public Schooling Bureaucracy.
ERIC Educational Resources Information Center
Jull, Stephen K.
2002-01-01
The current bureaucratic model used in administering public education in Canada displays a systemic gender bias that results from sociopolitical-cultural assumptions concerning gender roles, capitalism, hierarchy, and patriarchy. A proposed neo-bureaucracy would replace individual ownership of success with an accent on teamwork and group…
Classification Objects, Ideal Observers & Generative Models
ERIC Educational Resources Information Center
Olman, Cheryl; Kersten, Daniel
2004-01-01
A successful vision system must solve the problem of deriving geometrical information about three-dimensional objects from two-dimensional photometric input. The human visual system solves this problem with remarkable efficiency, and one challenge in vision research is to understand how neural representations of objects are formed and what visual…
Analyzing Hypermedia and Internet Communication Models in Educational Applications
ERIC Educational Resources Information Center
Saxena, Anshu; Kothari, D. P.; Jain, Sudhir K.; Khurana, Amulya
2004-01-01
Hypermedia has long been considered to have great potential to support educational tasks and applications. Many success stories of hypermedia support in education have been reported. Much of this work has been done in the context of traditional closed hypermedia systems rather than more contemporary open hypermedia systems. Developing hypermedia…
Advances in POST2 End-to-End Descent and Landing Simulation for the ALHAT Project
NASA Technical Reports Server (NTRS)
Davis, Jody L.; Striepe, Scott A.; Maddock, Robert W.; Hines, Glenn D.; Paschall, Stephen, II; Cohanim, Babak E.; Fill, Thomas; Johnson, Michael C.; Bishop, Robert H.; DeMars, Kyle J.;
2008-01-01
Program to Optimize Simulated Trajectories II (POST2) is used as a basis for an end-to-end descent and landing trajectory simulation that is essential in determining design and integration capability and system performance of the lunar descent and landing system and environment models for the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. The POST2 simulation provides a six degree-of-freedom capability necessary to test, design and operate a descent and landing system for successful lunar landing. This paper presents advances in the development and model-implementation of the POST2 simulation, as well as preliminary system performance analysis, used for the testing and evaluation of ALHAT project system models.
Measurement of bio-impedance with a smart needle to confirm percutaneous kidney access.
Hernandez, D J; Sinkov, V A; Roberts, W W; Allaf, M E; Patriciu, A; Jarrett, T W; Kavoussi, L R; Stoianovici, D
2001-10-01
The traditional method of percutaneous renal access requires freehand needle placement guided by C-arm fluoroscopy, ultrasonography, or computerized tomography. This approach provides limited objective means for verifying successful access. We developed an impedance based percutaneous Smart Needle system and successfully used it to confirm collecting system access in ex vivo porcine kidneys. The Smart Needle consists of a modified 18 gauge percutaneous access needle with the inner stylet electrically insulated from the outer sheath. Impedance is measured between the exposed stylet tip and sheath using Model 4275 LCR meter (Hewlett-Packard, Sunnyvale, California). An ex vivo porcine kidney was distended by continuous gravity infusion of 100 cm. water saline from a catheter passed through the parenchyma into the collecting system. The Smart Needle was gradually inserted into the kidney to measure depth precisely using a robotic needle placement system, while impedance was measured continuously. The Smart Needle was inserted 4 times in each of 4 kidneys. When the needle penetrated the distended collecting system in 11 of 16 attempts, a characteristic sharp drop in resistivity was noted from 1.9 to 1.1 ohm m. Entry into the collecting system was confirmed by removing the stylet and observing fluid flow from the sheath. This characteristic impedance change was observed only at successful entry into the collecting system. A characteristic sharp drop in impedance signifies successful entry into the collecting system. The Smart Needle system may prove useful for percutaneous kidney access.
New approaches in agent-based modeling of complex financial systems
NASA Astrophysics Data System (ADS)
Chen, Ting-Ting; Zheng, Bo; Li, Yan; Jiang, Xiong-Fei
2017-12-01
Agent-based modeling is a powerful simulation technique to understand the collective behavior and microscopic interaction in complex financial systems. Recently, the concept for determining the key parameters of agent-based models from empirical data instead of setting them artificially was suggested. We first review several agent-based models and the new approaches to determine the key model parameters from historical market data. Based on the agents' behaviors with heterogeneous personal preferences and interactions, these models are successful in explaining the microscopic origination of the temporal and spatial correlations of financial markets. We then present a novel paradigm combining big-data analysis with agent-based modeling. Specifically, from internet query and stock market data, we extract the information driving forces and develop an agent-based model to simulate the dynamic behaviors of complex financial systems.
Engineering-Level Model Atmospheres for Titan and Neptune
NASA Technical Reports Server (NTRS)
Justus, C. G.; Duvall, Aleta; Johnson, D. L.
2003-01-01
Engineering-level atmospheric models for Titan and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications in missions to the outer planets. Analogous to highly successful Global Reference Atmospheric Models for Earth (GRAM, Justus et al., 2000) and Mars (Mars-GRAM, Justus and Johnson, 2001, Justus et al., 2002) the new models are called Titan-GRAM and Neptune-GRAM. Like GRAM and Mars-GRAM, an important feature of Titan-GRAM and Neptune-GRAM is their ability to simulate quasi-random perturbations for Monte- Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design.
Computational models of an inductive power transfer system for electric vehicle battery charge
NASA Astrophysics Data System (ADS)
Anele, A. O.; Hamam, Y.; Chassagne, L.; Linares, J.; Alayli, Y.; Djouani, K.
2015-09-01
One of the issues to be solved for electric vehicles (EVs) to become a success is the technical solution of its charging system. In this paper, computational models of an inductive power transfer (IPT) system for EV battery charge are presented. Based on the fundamental principles behind IPT systems, 3 kW single phase and 22 kW three phase IPT systems for Renault ZOE are designed in MATLAB/Simulink. The results obtained based on the technical specifications of the lithium-ion battery and charger type of Renault ZOE show that the models are able to provide the total voltage required by the battery. Also, considering the charging time for each IPT model, they are capable of delivering the electricity needed to power the ZOE. In conclusion, this study shows that the designed computational IPT models may be employed as a support structure needed to effectively power any viable EV.
Thinking Together: Modeling Clinical Decision-Support as a Sociotechnical System
Hussain, Mustafa I.; Reynolds, Tera L.; Mousavi, Fatemeh E.; Chen, Yunan; Zheng, Kai
2017-01-01
Computerized clinical decision-support systems are members of larger sociotechnical systems, composed of human and automated actors, who send, receive, and manipulate artifacts. Sociotechnical consideration is rare in the literature. This makes it difficult to comparatively evaluate the success of CDS implementations, and it may also indicate that sociotechnical context receives inadequate consideration in practice. To facilitate sociotechnical consideration, we developed the Thinking Together model, a flexible diagrammatical means of representing CDS systems as sociotechnical systems. To develop this model, we examined the literature with the lens of Distributed Cognition (DCog) theory. We then present two case studies of vastly different CDSSs, one almost fully automated and the other with minimal automation, to illustrate the flexibility of the Thinking Together model. We show that this model, informed by DCog and the CDS literature, are capable of supporting both research, by enabling comparative evaluation, and practice, by facilitating explicit sociotechnical planning and communication. PMID:29854164
Interagency Collaborative Team Model for Capacity Building to Scale-Up Evidence-Based Practice
Hurlburt, Michael; Aarons, Gregory A; Fettes, Danielle; Willging, Cathleen; Gunderson, Lara; Chaffin, Mark J
2015-01-01
Background System-wide scale up of evidence-based practice (EBP) is a complex process. Yet, few strategic approaches exist to support EBP implementation and sustainment across a service system. Building on the Exploration, Preparation, Implementation, and Sustainment (EPIS) implementation framework, we developed and are testing the Interagency Collaborative Team (ICT) process model to implement an evidence-based child neglect intervention (i.e., SafeCare®) within a large children’s service system. The ICT model emphasizes the role of local agency collaborations in creating structural supports for successful implementation. Methods We describe the ICT model and present preliminary qualitative results from use of the implementation model in one large scale EBP implementation. Qualitative interviews were conducted to assess challenges in building system, organization, and home visitor collaboration and capacity to implement the EBP. Data collection and analysis centered on EBP implementation issues, as well as the experiences of home visitors under the ICT model. Results Six notable issues relating to implementation process emerged from participant interviews, including: (a) initial commitment and collaboration among stakeholders, (b) leadership, (c) communication, (d) practice fit with local context, (e) ongoing negotiation and problem solving, and (f) early successes. These issues highlight strengths and areas for development in the ICT model. Conclusions Use of the ICT model led to sustained and widespread use of SafeCare in one large county. Although some aspects of the implementation model may benefit from enhancement, qualitative findings suggest that the ICT process generates strong structural supports for implementation and creates conditions in which tensions between EBP structure and local contextual variations can be resolved in ways that support the expansion and maintenance of an EBP while preserving potential for public health benefit. PMID:27512239
Interagency Collaborative Team Model for Capacity Building to Scale-Up Evidence-Based Practice.
Hurlburt, Michael; Aarons, Gregory A; Fettes, Danielle; Willging, Cathleen; Gunderson, Lara; Chaffin, Mark J
2014-04-01
System-wide scale up of evidence-based practice (EBP) is a complex process. Yet, few strategic approaches exist to support EBP implementation and sustainment across a service system. Building on the Exploration, Preparation, Implementation, and Sustainment (EPIS) implementation framework, we developed and are testing the Interagency Collaborative Team (ICT) process model to implement an evidence-based child neglect intervention (i.e., SafeCare®) within a large children's service system. The ICT model emphasizes the role of local agency collaborations in creating structural supports for successful implementation. We describe the ICT model and present preliminary qualitative results from use of the implementation model in one large scale EBP implementation. Qualitative interviews were conducted to assess challenges in building system, organization, and home visitor collaboration and capacity to implement the EBP. Data collection and analysis centered on EBP implementation issues, as well as the experiences of home visitors under the ICT model. Six notable issues relating to implementation process emerged from participant interviews, including: (a) initial commitment and collaboration among stakeholders, (b) leadership, (c) communication, (d) practice fit with local context, (e) ongoing negotiation and problem solving, and (f) early successes. These issues highlight strengths and areas for development in the ICT model. Use of the ICT model led to sustained and widespread use of SafeCare in one large county. Although some aspects of the implementation model may benefit from enhancement, qualitative findings suggest that the ICT process generates strong structural supports for implementation and creates conditions in which tensions between EBP structure and local contextual variations can be resolved in ways that support the expansion and maintenance of an EBP while preserving potential for public health benefit.
NASA Technical Reports Server (NTRS)
Scott, Robert C.; Vetter, Travis K.; Penning, Kevin B.; Coulson, David A.; Heeg, Jennifer.
2013-01-01
of a two part document. Part 2 is titled: "Aeroservoelastic Testing of Free Flying Wind Tunnel Models, Part 2: A Centerline Supported Fullspan Model Tested for Gust Load Alleviation." A team comprised of the Air Force Research Laboratory (AFRL), Northrop Grumman, Lockheed Martin, and the NASA Langley Research Center conducted three aeroservoelastic wind tunnel tests in the Transonic Dynamics Tunnel to demonstrate active control technologies relevant to large, flexible vehicles. In the first of these three tests, a semispan, aeroelastically scaled, wind tunnel model of a flying wing SensorCraft vehicle was mounted to a force balance to demonstrate gust load alleviation. In the second and third tests, the same wing was mated to a new, multi-degree of freedom, sidewall mount. This mount allowed the half-span model to translate vertically and pitch at the wing root, allowing better simulation of the full span vehicle's rigid body modes. Gust load alleviation (GLA) and Body freedom flutter (BFF) suppression were successfully demonstrated. The rigid body degrees-of-freedom required that the model be flown in the wind tunnel using an active control system. This risky mode of testing necessitated that a model arrestment system be integrated into the new mount. The safe and successful completion of these free flying tests required the development and integration of custom hardware and software. This paper describes the many systems, software, and procedures that were developed as part of this effort.
Building Excellence in Project Execution: Integrated Project Management
2015-04-30
challenge by adopting and refining the CMMI Model and building the tenets of integrated project management (IPM) into project planning and execution...Systems Center Pacific (SSC Pacific) is addressing this challenge by adopting and refining the CMMI Model, and building the tenets of integrated project...successfully managing stakeholder expectations and meeting requirements. Under the Capability Maturity Model Integration ( CMMI ), IPM is defined as
T. M. Barrett
2001-01-01
Landscape assessment and planning often depend on the ability to predict change of vegetation. This report compares four modeling systems (FETM, LANDSUM, SIMPPLLE, and VDDT) that can be used to understand changes resulting from succession, natural disturbance, and management activities. The four models may be useful for regional or local assessments in National Forest...
Diabetes: Models, Signals, and Control
Cobelli, Claudio; Man, Chiara Dalla; Sparacino, Giovanni; Magni, Lalo; De Nicolao, Giuseppe; Kovatchev, Boris P.
2010-01-01
The control of diabetes is an interdisciplinary endeavor, which includes a significant biomedical engineering component, with traditions of success beginning in the early 1960s. It began with modeling of the insulin-glucose system, and progressed to large-scale in silico experiments, and automated closed-loop control (artificial pancreas). Here, we follow these engineering efforts through the last, almost 50 years. We begin with the now classic minimal modeling approach and discuss a number of subsequent models, which have recently resulted in the first in silico simulation model accepted as substitute to animal trials in the quest for optimal diabetes control. We then review metabolic monitoring, with a particular emphasis on the new continuous glucose sensors, on the analyses of their time-series signals, and on the opportunities that they present for automation of diabetes control. Finally, we review control strategies that have been successfully employed in vivo or in silico, presenting a promise for the development of a future artificial pancreas and, in particular, discuss a modular architecture for building closed-loop control systems, including insulin delivery and patient safety supervision layers. We conclude with a brief discussion of the unique interactions between human physiology, behavioral events, engineering modeling and control relevant to diabetes. PMID:20936056
NASA Technical Reports Server (NTRS)
Scott, Robert C.; Castelluccio, Mark A.; Coulson, David A.; Heeg, Jennifer
2011-01-01
A team comprised of the Air Force Research Laboratory (AFRL), Boeing, and the NASA Langley Research Center conducted three aeroservoelastic wind-tunnel tests in the Transonic Dynamics Tunnel to demonstrate active control technologies relevant to large, exible vehicles. In the first of these three tests, a full-span, aeroelastically scaled, wind-tunnel model of a joined-wing SensorCraft vehicle was mounted to a force balance to acquire a basic aerodynamic data set. In the second and third tests, the same wind-tunnel model was mated to a new, two-degree-of-freedom, beam mount. This mount allowed the full-span model to translate vertically and pitch. Trimmed flight at -10% static margin and gust load alleviation were successfully demonstrated. The rigid body degrees of freedom required that the model be own in the wind tunnel using an active control system. This risky mode of testing necessitated that a model arrestment system be integrated into the new mount. The safe and successful completion of these free-flying tests required the development and integration of custom hardware and software. This paper describes the many systems, software, and procedures that were developed as part of this effort. The balance and free ying wind-tunnel tests will be summarized. The design of the trim and gust load alleviation control laws along with the associated results will also be discussed.
Quebec mental health services networks: models and implementation
Fleury, Marie-Josée
2005-01-01
Abstract Purpose In the transformation of health care systems, the introduction of integrated service networks is considered to be one of the main solutions for enhancing efficiency. In the last few years, a wealth of literature has emerged on the topic of services integration. However, the question of how integrated service networks should be modelled to suit different implementation contexts has barely been touched. To fill that gap, this article presents four models for the organization of mental health integrated networks. Data sources The proposed models are drawn from three recently published studies on mental health integrated services in the province of Quebec (Canada) with the author as principal investigator. Description Following an explanation of the concept of integrated service network and a description of the Quebec context for mental health networks, the models, applicable in all settings: rural, urban or semi-urban, and metropolitan, and summarized in four figures, are presented. Discussion and conclusion To apply the models successfully, the necessity of rallying all the actors of a system, from the strategic, tactical and operational levels, according to the type of integration involved: functional/administrative, clinical and physician-system is highlighted. The importance of formalizing activities among organizations and actors in a network and reinforcing the governing mechanisms at the local level is also underlined. Finally, a number of integration strategies and key conditions of success to operationalize integrated service networks are suggested. PMID:16773157
Projection methods for the numerical solution of Markov chain models
NASA Technical Reports Server (NTRS)
Saad, Youcef
1989-01-01
Projection methods for computing stationary probability distributions for Markov chain models are presented. A general projection method is a method which seeks an approximation from a subspace of small dimension to the original problem. Thus, the original matrix problem of size N is approximated by one of dimension m, typically much smaller than N. A particularly successful class of methods based on this principle is that of Krylov subspace methods which utilize subspaces of the form span(v,av,...,A(exp m-1)v). These methods are effective in solving linear systems and eigenvalue problems (Lanczos, Arnoldi,...) as well as nonlinear equations. They can be combined with more traditional iterative methods such as successive overrelaxation, symmetric successive overrelaxation, or with incomplete factorization methods to enhance convergence.
A system dynamics model of a large R&D program
NASA Astrophysics Data System (ADS)
Ahn, Namsung
Organizations with large R&D activities must deal with a hierarchy of decision regarding resource allocation. At the highest level of allocation, the decision is related to the total allocation to R&D as some portion of revenue. The middle level of allocation deals with the allocation among phases of the R&D process. The lowest level of decisions relates to the resource allocation to specific projects within a specific phase. This study focuses on developing an R&D model to deal with the middle level of allocation, i.e., the allocation among phases of research such as basic research, development, and demonstration. The methodology used to develop the R&D model is System Dynamics. Our modeling concept is innovative in representing each phase of R&D as consisting of two parts: projects under way, and an inventory of successful but not-yet- exploited projects. In a simple world, this concept can yield an exact analytical solution for allocation of resources among phases. But in a real world, the concept should be improved by adding more complex structures with nonlinear behaviors. Two particular nonlinear feedbacks are incorporated into the R&D model. The probability of success for any specific project is assumed partly dependent upon resources allocated to the project. Further, the time required to reach a conclusion regarding the success or failure of a project is also assumed dependent upon the level of resources allocated. In addition, the number of successful projects partly depends on the inventory of potential ideas in the previous stage that can be exploited. This model can provide R&D management with insights into the effect of changing allocations to phases whether those changes are internally or externally driven. With this model, it is possible to study the effectiveness of management decisions in a continuous fashion. Managers can predict payoffs for a host of different policies. In addition, as new research results accumulate, a re- assessment of program goals can be implemented easily and allocations adjusted to enhance continuously the likelihood of success, and to optimize payoffs. Finally, this model can give managers a quantitative rationale for program evaluation and permit the quantitative assessment of various externally imposed changes. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
The modeling of an automotive electronic control system and the application of optimizing methods
NASA Astrophysics Data System (ADS)
Zhang, Yansheng; Yang, Zhigang; Zhang, Xiang
2005-12-01
Now, MATLAB/SIMULINK software is popularly used by automotive electronic control designers to develop automotive electronic control systems and perform numerical simulations. But they will face problems, such as value initialization in the "integrator" block, conversion among different data types, selection of "if" block and "switch" block, realization of the "if-clause" under multiple options and the auto-switching control, etc. Taking as an example the designing of an Automated Mechanical Transmission (AMT) system, this paper discusses some techniques and methods for modeling the automotive electronic control system with MATLAB/SIMULINK, offering designers some successful examples.
Experimental investigation of elastic mode control on a model of a transport aircraft
NASA Technical Reports Server (NTRS)
Abramovitz, M.; Heimbaugh, R. M.; Nomura, J. K.; Pearson, R. M.; Shirley, W. A.; Stringham, R. H.; Tescher, E. L.; Zoock, I. E.
1981-01-01
A 4.5 percent DC-10 derivative flexible model with active controls is fabricated, developed, and tested to investigate the ability to suppress flutter and reduce gust loads with active controlled surfaces. The model is analyzed and tested in both semispan and complete model configuration. Analytical methods are refined and control laws are developed and successfully tested on both versions of the model. A 15 to 25 percent increase in flutter speed due to the active system is demonstrated. The capability of an active control system to significantly reduce wing bending moments due to turbulence is demonstrated. Good correlation is obtained between test and analytical prediction.
Investigation of crew restraint system biomechanics. Report for May 79-Mar 81
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phillips, N.S.; Thomson, R.A.; Fiscus, I.B.
1982-05-01
Experimental data were collected and analyses were performed to study the influence of the dynamic mechanical properties of restraint system components on human response to impact and restraint system haulback. Tests were accomplished to isolate the characteristics of the restraint system and the human body. Three restraint webbing materials were studied at varied strain rates. A pyrotechnically powered inertia reel was tested, but could not be analytically modeled successfully. Analytical models of the human and restraint system were used to study the influence of restraint material properties changes on human response parameters. An analytical model of a rhesus monkey wasmore » also used to study the efficacy of animal tests and scaling techniques to evaluate restraint systems for human use applications.« less
Risk transfer modeling among hierarchically associated stakeholders in development of space systems
NASA Astrophysics Data System (ADS)
Henkle, Thomas Grove, III
Research develops an empirically derived cardinal model that prescribes handling and transfer of risks between organizations with hierarchical relationships. Descriptions of mission risk events, risk attitudes, and conditions for risk transfer are determined for client and underwriting entities associated with acquisition, production, and deployment of space systems. The hypothesis anticipates that large client organizations should be able to assume larger dollar-value risks of a program in comparison to smaller organizations even though many current risk transfer arrangements via space insurance violate this hypothesis. A literature survey covers conventional and current risk assessment methods, current techniques used in the satellite industry for complex system development, cardinal risk modeling, and relevant aspects of utility theory. Data gathered from open literature on demonstrated launch vehicle and satellite in-orbit reliability, annual space insurance premiums and losses, and ground fatalities and range damage associated with satellite launch activities are presented. Empirically derived models are developed for risk attitudes of space system clients and third-party underwriters associated with satellite system development and deployment. Two application topics for risk transfer are examined: the client-underwriter relationship on assumption or transfer of risks associated with first-year mission success, and statutory risk transfer agreements between space insurance underwriters and the US government to promote growth in both commercial client and underwriting industries. Results indicate that client entities with wealth of at least an order of magnitude above satellite project costs should retain risks to first-year mission success despite present trends. Furthermore, large client entities such as the US government should never pursue risk transfer via insurance under previously demonstrated probabilities of mission success; potential savings may reasonably exceed multiple tens of $millions per space project. Additional results indicate that current US government statutory arrangements on risk sharing with underwriting entities appears reasonable with respect to stated objectives. This research combines aspects of multiple disciplines to include risk management, decision theory, utility theory, and systems architecting. It also demonstrates development of a more general theory on prescribing risk transfer criteria between distinct, but hierarchically associated entities involved in complex system development with applicability to a variety of technical domains.
Sumner, T; Shephard, E; Bogle, I D L
2012-09-07
One of the main challenges in the development of mathematical and computational models of biological systems is the precise estimation of parameter values. Understanding the effects of uncertainties in parameter values on model behaviour is crucial to the successful use of these models. Global sensitivity analysis (SA) can be used to quantify the variability in model predictions resulting from the uncertainty in multiple parameters and to shed light on the biological mechanisms driving system behaviour. We present a new methodology for global SA in systems biology which is computationally efficient and can be used to identify the key parameters and their interactions which drive the dynamic behaviour of a complex biological model. The approach combines functional principal component analysis with established global SA techniques. The methodology is applied to a model of the insulin signalling pathway, defects of which are a major cause of type 2 diabetes and a number of key features of the system are identified.
Design Considerations for a Launch Vehicle Development Flight Instrumentation System
NASA Technical Reports Server (NTRS)
Johnson, Martin L.; Crawford, Kevin
2011-01-01
When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.
Limits of localized control in extended nonlinear systems
NASA Astrophysics Data System (ADS)
Handel, Andreas
We investigate the limits of localized linear control in spatially extended, nonlinear systems. Spatially extended, nonlinear systems can be found in virtually every field of engineering and science. An important category of such systems are fluid flows. Fluid flows play an important role in many commercial applications, for instance in the chemical, pharmaceutical and food-processing industries. Other important fluid flows include air- or water flows around cars, planes or ships. In all these systems, it is highly desirable to control the flow of the respective fluid. For instance control of the air flow around an airplane or car leads to better fuel-economy and reduced noise production. Usually, it is impossible to apply control everywhere. Consider an airplane: It would not be feasibly to cover the whole body of the plane with control units. Instead, one can place the control units at localized regions, such as points along the edge of the wings, spaced as far apart from each other as possible. These considerations lead to an important question: For a given system, what is the minimum number of localized controllers that still ensures successful control? Too few controllers will not achieve control, while using too many leads to unnecessary expenses and wastes resources. To answer this question, we study localized control in a class of model equations. These model equations are good representations of many real fluid flows. Using these equations, we show how one can design localized control that renders the system stable. We study the properties of the control and derive several expressions that allow us to determine the limits of successful control. We show how the number of controllers that are needed for successful control depends on the size and type of the system, as well as the way control is implemented. We find that especially the nonlinearities and the amount of noise present in the system play a crucial role. This analysis allows us to determine under which circumstances a given number of controllers can successfully stabilize a given system.
Determinants of successful clinical networks: the conceptual framework and study protocol.
Haines, Mary; Brown, Bernadette; Craig, Jonathan; D'Este, Catherine; Elliott, Elizabeth; Klineberg, Emily; McInnes, Elizabeth; Middleton, Sandy; Paul, Christine; Redman, Sally; Yano, Elizabeth M
2012-03-13
Clinical networks are increasingly being viewed as an important strategy for increasing evidence-based practice and improving models of care, but success is variable and characteristics of networks with high impact are uncertain. This study takes advantage of the variability in the functioning and outcomes of networks supported by the Australian New South Wales (NSW) Agency for Clinical Innovation's non-mandatory model of clinical networks to investigate the factors that contribute to the success of clinical networks. The objective of this retrospective study is to examine the association between external support, organisational and program factors, and indicators of success among 19 clinical networks over a three-year period (2006-2008). The outcomes (health impact, system impact, programs implemented, engagement, user perception, and financial leverage) and explanatory factors will be collected using a web-based survey, interviews, and record review. An independent expert panel will provide judgements about the impact or extent of each network's initiatives on health and system impacts. The ratings of the expert panel will be the outcome used in multivariable analyses. Following the rating of network success, a qualitative study will be conducted to provide a more in-depth examination of the most successful networks. This is the first study to combine quantitative and qualitative methods to examine the factors that contribute to the success of clinical networks and, more generally, is the largest study of clinical networks undertaken. The adaptation of expert panel methods to rate the impacts of networks is the methodological innovation of this study. The proposed project will identify the conditions that should be established or encouraged by agencies developing clinical networks and will be of immediate use in forming strategies and programs to maximise the effectiveness of such networks.
Model-Based Systems Engineering in Concurrent Engineering Centers
NASA Technical Reports Server (NTRS)
Iwata, Curtis; Infeld, Samantha; Bracken, Jennifer Medlin; McGuire; McQuirk, Christina; Kisdi, Aron; Murphy, Jonathan; Cole, Bjorn; Zarifian, Pezhman
2015-01-01
Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a focused design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.
Model-Based Systems Engineering in Concurrent Engineering Centers
NASA Technical Reports Server (NTRS)
Iwata, Curtis; Infeld, Samatha; Bracken, Jennifer Medlin; McGuire, Melissa; McQuirk, Christina; Kisdi, Aron; Murphy, Jonathan; Cole, Bjorn; Zarifian, Pezhman
2015-01-01
Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a narrow design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.
Decision support systems and the healthcare strategic planning process: a case study.
Lundquist, D L; Norris, R M
1991-01-01
The repertoire of applications that comprises health-care decision support systems (DSS) includes analyses of clinical, financial, and operational activities. As a whole, these applications facilitate developing comprehensive and interrelated business and medical models that support the complex decisions required to successfully manage today's health-care organizations. Kennestone Regional Health Care System's use of DSS to facilitate strategic planning has precipitated marked changes in the organization's method of determining capital allocations. This case study discusses Kennestone's use of DSS in the strategic planning process, including profiles of key DSS modeling components.
Tonges, Mary; Ray, Joel D; Herman, Suzanne; McCann, Meghan
2018-04-01
Patient satisfaction is a key component of healthcare organizations' performance. Providing a consistent, positive patient experience across a system can be challenging. This article describes an organization's approach to achieving this goal by implementing a successful model developed at the flagship academic healthcare center across an 8-hospital system. The Carolina Care at University of North Carolina Health Care initiative has resulted in substantive qualitative and quantitative benefits including higher patient experience scores for both overall rating and nurse communication.
Min, Yul Ha; Park, Hyeoun-Ae; Chung, Eunja; Lee, Hyunsook
2013-12-01
The purpose of this paper is to describe the components of a next-generation electronic nursing records system ensuring full semantic interoperability and integrating evidence into the nursing records system. A next-generation electronic nursing records system based on detailed clinical models and clinical practice guidelines was developed at Seoul National University Bundang Hospital in 2013. This system has two components, a terminology server and a nursing documentation system. The terminology server manages nursing narratives generated from entity-attribute-value triplets of detailed clinical models using a natural language generation system. The nursing documentation system provides nurses with a set of nursing narratives arranged around the recommendations extracted from clinical practice guidelines. An electronic nursing records system based on detailed clinical models and clinical practice guidelines was successfully implemented in a hospital in Korea. The next-generation electronic nursing records system can support nursing practice and nursing documentation, which in turn will improve data quality.
NASA Technical Reports Server (NTRS)
Fisher, Jody l.; Striepe, Scott A.
2007-01-01
The Program to Optimize Simulated Trajectories II (POST2) is used as a basis for an end-to-end descent and landing trajectory simulation that is essential in determining the design and performance capability of lunar descent and landing system models and lunar environment models for the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project. This POST2-based ALHAT simulation provides descent and landing simulation capability by integrating lunar environment and lander system models (including terrain, sensor, guidance, navigation, and control models), along with the data necessary to design and operate a landing system for robotic, human, and cargo lunar-landing success. This paper presents the current and planned development and model validation of the POST2-based end-to-end trajectory simulation used for the testing, performance and evaluation of ALHAT project system and models.
Tuot, Delphine S; Leeds, Kiren; Murphy, Elizabeth J; Sarkar, Urmimala; Lyles, Courtney R; Mekonnen, Tekeshe; Chen, Alice H M
2015-12-19
Access to specialty care remains a challenge for primary care providers and patients. Implementation of electronic referral and/or consultation (eCR) systems provides an opportunity for innovations in the delivery of specialty care. We conducted key informant interviews to identify drivers, facilitators, barriers and evaluation metrics of diverse eCR systems to inform widespread implementation of this model of specialty care delivery. Interviews were conducted with leaders of 16 diverse health care delivery organizations between January 2013 and April 2014. A limited snowball sampling approach was used for recruitment. Content analysis was used to examine key informant interview transcripts. Electronic referral systems, which provide referral management and triage by specialists, were developed to enhance tracking and operational efficiency. Electronic consultation systems, which encourage bi-directional communication between primary care and specialist providers facilitating longitudinal virtual co-management, were developed to improve access to specialty expertise. Integrated eCR systems leverage both functionalities to enhance the delivery of coordinated, specialty care at the population level. Elements of successful eCR system implementation included executive and clinician leadership, established funding models for specialist clinician reimbursement, and a commitment to optimizing clinician workflows. eCR systems have great potential to streamline access to and enhance the coordination of specialty care delivery. While different eCR models help solve different organizational challenges, all require institutional investments for successful implementation, such as funding for program management, leadership and clinician incentives.
Gurarie, David; King, Charles H.
2014-01-01
Mathematical modeling is widely used for predictive analysis of control options for infectious agents. Challenging problems arise for modeling host-parasite systems having complex life-cycles and transmission environments. Macroparasites, like Schistosoma, inhabit highly fragmented habitats that shape their reproductive success and distribution. Overdispersion and mating success are important factors to consider in modeling control options for such systems. Simpler models based on mean worm burden (MWB) formulations do not take these into account and overestimate transmission. Proposed MWB revisions have employed prescribed distributions and mating factor corrections to derive modified MWB models that have qualitatively different equilibria, including ‘breakpoints’ below which the parasite goes to extinction, suggesting the possibility of elimination via long-term mass-treatment control. Despite common use, no one has attempted to validate the scope and hypotheses underlying such MWB approaches. We conducted a systematic analysis of both the classical MWB and more recent “stratified worm burden” (SWB) modeling that accounts for mating and reproductive hurdles (Allee effect). Our analysis reveals some similarities, including breakpoints, between MWB and SWB, but also significant differences between the two types of model. We show the classic MWB has inherent inconsistencies, and propose SWB as a reliable alternative for projection of long-term control outcomes. PMID:25549362
Application of 3D Laser Scanner to Forensic Engineering.
Park, Chan-Seong; Jeon, Hong-Pil; Choi, Kwang-Soo; Kim, Jin-Pyo; Park, Nam-Kyu
2018-05-01
In the case of building collapses and overturned structures, a three-dimensional (3D) collapse or overturn model is required to reconstruct the accident. As construction sites become increasingly complex and large, 3D laser scanning is sometimes the best tool to accurately document and store the site conditions. This case report presents one case of a structure collapse and one case of an overturned crane reconstructed by a 3D laser scanner. In the case of structural collapse of a prefabricated shoring system, a 3D model reconstructed all the members successfully, a task that is nearly impossible using a scale such as a tape measure. The reconstructed prefabricated shoring system was verified through a structural analysis through comparison with the construction drawings to investigate faults in construction. In the case of the overturned crane, the jib angle and other major dimensions were successfully acquired through 3D laser scanning and used to estimate the working radius. As a result, the propriety of the working radius with the given lifting load was successfully determined. © 2017 American Academy of Forensic Sciences.
ERIC Educational Resources Information Center
Findik-Coskunçay, Duygu; Alkis, Nurcan; Özkan-Yildirim, Sevgi
2018-01-01
With the recent advances in information technologies, Learning Management Systems have taken on a significant role in providing educational resources. The successful use of these systems in higher education is important for the implementation, management and continuous improvement of e-learning services to increase the quality of learning. This…
Modeling Off-Nominal Behavior in SysML
NASA Technical Reports Server (NTRS)
Day, John C.; Donahue, Kenneth; Ingham, Michel; Kadesch, Alex; Kennedy, Andrew K.; Post, Ethan
2012-01-01
Specification and development of fault management functionality in systems is performed in an ad hoc way - more of an art than a science. Improvements to system reliability, availability, safety and resilience will be limited without infusion of additional formality into the practice of fault management. Key to the formalization of fault management is a precise representation of off-nominal behavior. Using the upcoming Soil Moisture Active-Passive (SMAP) mission for source material, we have modeled the off-nominal behavior of the SMAP system during its initial spin-up activity, using the System Modeling Language (SysML). In the course of developing these models, we have developed generic patterns for capturing off-nominal behavior in SysML. We show how these patterns provide useful ways of reasoning about the system (e.g., checking for completeness and effectiveness) and allow the automatic generation of typical artifacts (e.g., success trees and FMECAs) used in system analyses.
Application of a Systems Engineering Approach to Support Space Reactor Development
NASA Astrophysics Data System (ADS)
Wold, Scott
2005-02-01
In 1992, approximately 25 Russian and 12 U.S. engineers and technicians were involved in the transport, assembly, inspection, and testing of over 90 tons of Russian equipment associated with the Thermionic System Evaluation Test (TSET) Facility. The entire Russian Baikal Test Stand, consisting of a 5.79 m tall vacuum chamber and related support equipment, was reassembled and tested at the TSET facility in less than four months. In November 1992, the first non-nuclear operational test of a complete thermionic power reactor system in the U.S. was accomplished three months ahead of schedule and under budget. A major factor in this accomplishment was the application of a disciplined top-down systems engineering approach and application of a spiral development model to achieve the desired objectives of the TOPAZ International Program (TIP). Systems Engineering is a structured discipline that helps programs and projects conceive, develop, integrate, test and deliver products and services that meet customer requirements within cost and schedule. This paper discusses the impact of Systems Engineering and a spiral development model on the success of the TOPAZ International Program and how the application of a similar approach could help ensure the success of future space reactor development projects.
Accidental degeneracies in nonlinear quantum deformed systems
NASA Astrophysics Data System (ADS)
Aleixo, A. N. F.; Balantekin, A. B.
2011-09-01
We construct a multi-parameter nonlinear deformed algebra for quantum confined systems that includes many other deformed models as particular cases. We demonstrate that such systems exhibit the property of accidental pairwise energy level degeneracies. We also study, as a special case of our multi-parameter deformation formalism, the extension of the Tamm-Dancoff cutoff deformed oscillator and the occurrence of accidental pairwise degeneracy in the energy levels of the deformed system. As an application, we discuss the case of a trigonometric Rosen-Morse potential, which is successfully used in models for quantum confined systems, ranging from electrons in quantum dots to quarks in hadrons.
Model Guided Design and Development Process for an Electronic Health Record Training Program
He, Ze; Marquard, Jenna; Henneman, Elizabeth
2016-01-01
Effective user training is important to ensure electronic health record (EHR) implementation success. Though many previous studies report best practice principles and success and failure stories, current EHR training is largely empirically-based and often lacks theoretical guidance. In addition, the process of training development is underemphasized and underreported. A white paper by the American Medical Informatics Association called for models of user training for clinical information system implementation; existing instructional development models from learning theory provide a basis to meet this call. We describe in this paper our experiences and lessons learned as we adapted several instructional development models to guide our development of EHR user training. Specifically, we focus on two key aspects of this training development: training content and training process. PMID:28269940
Modelling clinical systemic lupus erythematosus: similarities, differences and success stories
Celhar, Teja
2017-01-01
Abstract Mouse models of SLE have been indispensable tools to study disease pathogenesis, to identify genetic susceptibility loci and targets for drug development, and for preclinical testing of novel therapeutics. Recent insights into immunological mechanisms of disease progression have boosted a revival in SLE drug development. Despite promising results in mouse studies, many novel drugs have failed to meet clinical end points. This is probably because of the complexity of the disease, which is driven by polygenic predisposition and diverse environmental factors, resulting in a heterogeneous clinical presentation. Each mouse model recapitulates limited aspects of lupus, especially in terms of the mechanism underlying disease progression. The main mouse models have been fairly successful for the evaluation of broad-acting immunosuppressants. However, the advent of targeted therapeutics calls for a selection of the most appropriate model(s) for testing and, ultimately, identification of patients who will be most likely to respond. PMID:28013204
Current progress in use of adipose derived stem cells in peripheral nerve regeneration
Zack-Williams, Shomari DL; Butler, Peter E; Kalaskar, Deepak M
2015-01-01
Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modulate the subsequent immune response. The level of nerve recovery is strongly linked to the severity of the initial injury despite the significant advancements in imaging and surgical techniques. Multiple experimental models have been used with varying successes to augment the natural regenerative processes which occur following nerve injury. Stem cell therapy in peripheral nerve injury may be an important future intervention to improve the best attainable clinical results. In particular adipose derived stem cells (ADSCs) are multipotent mesenchymal stem cells similar to bone marrow derived stem cells, which are thought to have neurotrophic properties and the ability to differentiate into multiple lineages. They are ubiquitous within adipose tissue; they can form many structures resembling the mature adult peripheral nervous system. Following early in vitro work; multiple small and large animal in vivo models have been used in conjunction with conduits, autografts and allografts to successfully bridge the peripheral nerve gap. Some of the ADSC related neuroprotective and regenerative properties have been elucidated however much work remains before a model can be used successfully in human peripheral nerve injury (PNI). This review aims to provide a detailed overview of progress made in the use of ADSC in PNI, with discussion on the role of a tissue engineered approach for PNI repair. PMID:25621105
2010-08-01
petroleum industry. Moreover, heterogeneity control strategies can be applied to improve the efficiency of a variety of in situ remediation technologies...conditions that differ significantly from those found in environmental systems . Therefore many of the design criteria used by the petroleum industry for...were helpful in constructing numerical models in up-scaled systems (2-D tanks). The UTCHEM model was able to successfully simulate 2-D experimental
NASA Technical Reports Server (NTRS)
Kloesel, Kurt J.; Ratnayake, Nalin A.; Clark, Casie M.
2011-01-01
Access to space is in the early stages of commercialization. Private enterprises, mainly under direct or indirect subsidy by the government, have been making headway into the LEO launch systems infrastructure, of small-weight-class payloads of approximately 1000 lbs. These moderate gains have emboldened the launch industry and they are poised to move into the middle-weight class (roughly 5000 lbs). These commercially successful systems are based on relatively straightforward LOX-RP, two-stage, bi-propellant rocket technology developed by the government 40 years ago, accompanied by many technology improvements. In this paper we examine a known generic LOX-RP system with the focus on the booster stage (1st stage). The booster stage is then compared to modeled Rocket-Based and Turbine-Based Combined Cycle booster stages. The air-breathing propulsion stages are based on/or extrapolated from known performance parameters of ground tested RBCC (the Marquardt Ejector Ramjet) and TBCC (the SR-71/J-58 engine) data. Validated engine models using GECAT and SCCREAM are coupled with trajectory optimization and analysis in POST-II to explore viable launch scenarios using hypothetical aerospaceplane platform obeying the aerodynamic model of the SR-71. Finally, and assessment is made of the requisite research technology advances necessary for successful commercial and government adoption of combined-cycle engine systems for space access.
Analysis of brute-force break-ins of a palmprint authentication system.
Kong, Adams W K; Zhang, David; Kamel, Mohamed
2006-10-01
Biometric authentication systems are widely applied because they offer inherent advantages over classical knowledge-based and token-based personal-identification approaches. This has led to the development of products using palmprints as biometric traits and their use in several real applications. However, as biometric systems are vulnerable to replay, database, and brute-force attacks, such potential attacks must be analyzed before biometric systems are massively deployed in security systems. This correspondence proposes a projected multinomial distribution for studying the probability of successfully using brute-force attacks to break into a palmprint system. To validate the proposed model, we have conducted a simulation. Its results demonstrate that the proposed model can accurately estimate the probability. The proposed model indicates that it is computationally infeasible to break into the palmprint system using brute-force attacks.
Ultramicrowave communications system, phase 3
NASA Technical Reports Server (NTRS)
1981-01-01
The ultramicrowave communications system program investigated the feasibility of a solid state system that meets the projected space to space requirements, while using the advantages of the 100 to 200 GHz band. The program successfully demonstrated a laboratory model of a high frequency communications system operating between 100 to 200 GHz. In the process, vendor claims for performance specifications of discrete components were evaluated, and a window was provided into system design and integration problems.
The UNIX Operating System: A Model for Software Design.
Kernighan, B W; Morgan, S P
1982-02-12
The UNIX operating system, a general-purpose time-sharng system, has, without marketing, advertising, or technical support, become widely used by universities and scientific research establishments. It is the de facto standard of comparison for such systems and has spawned a small industry of suppliers of UNIX variants and look-alikes. This article attempts to uncover the reasons for its success and to draw some lessons for the future of operating systems.
Graceful Failure and Societal Resilience Analysis Via Agent-Based Modeling and Simulation
NASA Astrophysics Data System (ADS)
Schopf, P. S.; Cioffi-Revilla, C.; Rogers, J. D.; Bassett, J.; Hailegiorgis, A. B.
2014-12-01
Agent-based social modeling is opening up new methodologies for the study of societal response to weather and climate hazards, and providing measures of resiliency that can be studied in many contexts, particularly in coupled human and natural-technological systems (CHANTS). Since CHANTS are complex adaptive systems, societal resiliency may or may not occur, depending on dynamics that lack closed form solutions. Agent-based modeling has been shown to provide a viable theoretical and methodological approach for analyzing and understanding disasters and societal resiliency in CHANTS. Our approach advances the science of societal resilience through computational modeling and simulation methods that complement earlier statistical and mathematical approaches. We present three case studies of social dynamics modeling that demonstrate the use of these agent based models. In Central Asia, we exmaine mutltiple ensemble simulations with varying climate statistics to see how droughts and zuds affect populations, transmission of wealth across generations, and the overall structure of the social system. In Eastern Africa, we explore how successive episodes of drought events affect the adaptive capacity of rural households. Human displacement, mainly, rural to urban migration, and livelihood transition particularly from pastoral to farming are observed as rural households interacting dynamically with the biophysical environment and continually adjust their behavior to accommodate changes in climate. In the far north case we demonstrate one of the first successful attempts to model the complete climate-permafrost-infrastructure-societal interaction network as a complex adaptive system/CHANTS implemented as a ``federated'' agent-based model using evolutionary computation. Analysis of population changes resulting from extreme weather across these and other cases provides evidence for the emergence of new steady states and shifting patterns of resilience.
Implementing an Indigenous Community Education Program: An Interim Report.
ERIC Educational Resources Information Center
Nabokov, Peter
Institutional success of an instructional model that featured peer instruction, a strict performance orientation, and an insistence on mastery of specific skills led developers to believe the same model could be used by communities to disseminate skills and information at low cost and with efficiency. The system was utilized in setting up an…
ERIC Educational Resources Information Center
Davidson, J. Cody
2015-01-01
Today, community colleges are challenged to maintain their historical identity of open access while increasing student success. This challenge is particularly salient in the context of performance-based funding models. These models create student achievements, which determine institutional levels of state funding. Therefore, these new student…
A quantitative risk model for early lifecycle decision making
NASA Technical Reports Server (NTRS)
Feather, M. S.; Cornford, S. L.; Dunphy, J.; Hicks, K.
2002-01-01
Decisions made in the earliest phases of system development have the most leverage to influence the success of the entire development effort, and yet must be made when information is incomplete and uncertain. We have developed a scalable cost-benefit model to support this critical phase of early-lifecycle decision-making.
Rethinking School Bullying: Towards an Integrated Model
ERIC Educational Resources Information Center
Dixon, Roz; Smith, Peter K.
2011-01-01
What would make anti-bullying initiatives more successful? This book offers a new approach to the problem of school bullying. The question of what constitutes a useful theory of bullying is considered and suggestions are made as to how priorities for future research might be identified. The integrated, systemic model of school bullying introduced…
Teaching Complex Dynamic Systems to Young Students with StarLogo
ERIC Educational Resources Information Center
Klopfer, Eric; Yoon, Susan; Um, Tricia
2005-01-01
In this paper, we report on a program of study called Adventures in Modeling that challenges the traditional scientific method approach in science classrooms using StarLogo modeling software. Drawing upon previous successful efforts with older students, and the related work of other projects working with younger students, we explore: (a) What can…
ERIC Educational Resources Information Center
Fletcher, J. D.; Sottilare, Robert A.
2018-01-01
Teams and teamwork are ubiquitous in military and civilian organizations. Their importance to organizational success cannot be overstated. This article describes the relationship and effect of three concepts: Intelligent Tutoring Systems (ITSs), shared mental models, and teamwork. The nexus between these concepts is examined to determine its…
NASA Astrophysics Data System (ADS)
Wang, Yu-Ying; Liu, Yu-Xue; Lu, Hao-Hao; Yang, Rui-Qin; Yang, Sheng-Mao
2018-05-01
A hydroxyapatite-biochar nanocomposite (HAP-BC) was successfully fabricated and its physicochemical properties characterized. The analyses showed that HAP nanoparticles were successfully loaded on the biochar surface. The adsorption of Pb(II), Cu(II), and Zn(II) by HAP-BC was systematically studied in single and ternary metal systems. The results demonstrated that pH affects the adsorption of heavy metals onto HAP-BC. Regarding the adsorption kinetics, the pseudo-second-order model showed the best fit for all three heavy metal ions on HAP-BC. In both single and ternary metal ion systems, the adsorption isotherm of Pb(II) by HAP-BC followed Langmuir model, while those of Cu(II) and Zn(II) fitted well with Freundlich model. The maximum adsorption capacity for each tested metal by HAP-BC was higher than that of pristine rice straw biochar (especially for Pb(II)) or those of other reported adsorbents. Therefore, HAP-BC could explore as a new material for future application in heavy metal removal.
Trust Model for Protection of Personal Health Data in a Global Environment.
Ruotsalainen, Pekka; Blobel, Bernd
2017-01-01
Successful health care, eHealth, digital health, and personal health systems increasingly take place in cross-jurisdictional, dynamic and risk-encumbered information space. They require rich amount of personal health information (PHI). Trust is and will be the cornerstone and prerequisite for successful health services. In global environments, trust cannot be expected as granted. In this paper, health service in the global environment is perceived as a meta-system, and a trust management model is developed to support it. The predefined trusting belief currently used in health care is not transferable to global environments. In the authors' model, the level of trust is dynamically calculated from measurable attributes. These attributes describe trust features of the service provider and its environment. The calculated trust value or profile can be used in defining the risk service user has to accept when disclosing PHI, and in definition of additional privacy and security safeguards before disclosing PHI and/or using services.
A semi-Lagrangian advection scheme for radioactive tracers in the NCEP Regional Spectral Model (RSM)
NASA Astrophysics Data System (ADS)
Chang, E.-C.; Yoshimura, K.
2015-10-01
In this study, the non-iteration dimensional-split semi-Lagrangian (NDSL) advection scheme is applied to the National Centers for Environmental Prediction (NCEP) Regional Spectral Model (RSM) to alleviate the Gibbs phenomenon. The Gibbs phenomenon is a problem wherein negative values of positive-definite quantities (e.g., moisture and tracers) are generated by the spectral space transformation in a spectral model system. To solve this problem, the spectral prognostic specific humidity and radioactive tracer advection scheme is replaced by the NDSL advection scheme, which considers advection of tracers in a grid system without spectral space transformations. A regional version of the NDSL is developed in this study and is applied to the RSM. Idealized experiments show that the regional version of the NDSL is successful. The model runs for an actual case study suggest that the NDSL can successfully advect radioactive tracers (iodine-131 and cesium-137) without noise from the Gibbs phenomenon. The NDSL can also remove negative specific humidity values produced in spectral calculations without losing detailed features.
Vertical integration models to prepare health systems for capitation.
Cave, D G
1995-01-01
Health systems will profit most under capitation if their vertical integration strategy provides operational stability, a strong primary care physician base, efficient delivery of medical services, and geographic access to physicians. Staff- and equity-based systems best meet these characteristics for success because they have one governance structure and a defined mission statement. Moreover, physician bonds are strong because these systems maximize physicians' income potential and control the revenue stream.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hadgu, Teklu; Appel, Gordon John
Sandia National Laboratories (SNL) continued evaluation of total system performance assessment (TSPA) computing systems for the previously considered Yucca Mountain Project (YMP). This was done to maintain the operational readiness of the computing infrastructure (computer hardware and software) and knowledge capability for total system performance assessment (TSPA) type analysis, as directed by the National Nuclear Security Administration (NNSA), DOE 2010. This work is a continuation of the ongoing readiness evaluation reported in Lee and Hadgu (2014) and Hadgu et al. (2015). The TSPA computing hardware (CL2014) and storage system described in Hadgu et al. (2015) were used for the currentmore » analysis. One floating license of GoldSim with Versions 9.60.300, 10.5 and 11.1.6 was installed on the cluster head node, and its distributed processing capability was mapped on the cluster processors. Other supporting software were tested and installed to support the TSPA-type analysis on the server cluster. The current tasks included verification of the TSPA-LA uncertainty and sensitivity analyses, and preliminary upgrade of the TSPA-LA from Version 9.60.300 to the latest version 11.1. All the TSPA-LA uncertainty and sensitivity analyses modeling cases were successfully tested and verified for the model reproducibility on the upgraded 2014 server cluster (CL2014). The uncertainty and sensitivity analyses used TSPA-LA modeling cases output generated in FY15 based on GoldSim Version 9.60.300 documented in Hadgu et al. (2015). The model upgrade task successfully converted the Nominal Modeling case to GoldSim Version 11.1. Upgrade of the remaining of the modeling cases and distributed processing tasks will continue. The 2014 server cluster and supporting software systems are fully operational to support TSPA-LA type analysis.« less
Modeling the human body/seat system in a vibration environment.
Rosen, Jacob; Arcan, Mircea
2003-04-01
The vibration environment is a common man-made artificial surrounding with which humans have a limited tolerance to cope due to their body dynamics. This research studied the dynamic characteristics of a seated human body/seat system in a vibration environment. The main result is a multi degrees of freedom lumped parameter model that synthesizes two basic dynamics: (i) global human dynamics, the apparent mass phenomenon, including a systematic set of the model parameters for simulating various conditions like body posture, backrest, footrest, muscle tension, and vibration directions, and (ii) the local human dynamics, represented by the human pelvis/vibrating seat contact, using a cushioning interface. The model and its selected parameters successfully described the main effects of the apparent mass phenomenon compared to experimental data documented in the literature. The model provided an analytical tool for human body dynamics research. It also enabled a primary tool for seat and cushioning design. The model was further used to develop design guidelines for a composite cushion using the principle of quasi-uniform body/seat contact force distribution. In terms of evenly distributing the contact forces, the best result for the different materials and cushion geometries simulated in the current study was achieved using a two layer shaped geometry cushion built from three materials. Combining the geometry and the mechanical characteristics of a structure under large deformation into a lumped parameter model enables successful analysis of the human/seat interface system and provides practical results for body protection in dynamic environment.
Bing, Chenchen; Nofiele, Joris; Staruch, Robert; Ladouceur-Wodzak, Michelle; Chatzinoff, Yonatan; Ranjan, Ashish; Chopra, Rajiv
2015-01-01
Purpose Localised hyperthermia in rodent studies is challenging due to the small target size. This study describes the development and characterisation of an MRI-compatible high-intensity focused ultrasound (HIFU) system to perform localised mild hyperthermia treatments in rodent models. Material and methods The hyperthermia platform consisted of an MRI-compatible small animal HIFU system, focused transducers with sector-vortex lenses, a custom-made receive coil, and means to maintain systemic temperatures of rodents. The system was integrated into a 3T MR imager. Control software was developed to acquire images, process temperature maps, and adjust output power using a proportional-integral-derivative feedback control algorithm. Hyperthermia exposures were performed in tissue-mimicking phantoms and in a rodent model (n = 9). During heating, an ROI was assigned in the heated region for temperature control and the target temperature was 42 °C; 30 min mild hyperthermia treatment followed by a 10-min cooling procedure was performed on each animal. Results 3D-printed sector-vortex lenses were successful at creating annular focal regions which enables customisation of the heating volume. Localised mild hyperthermia performed in rats produced a mean ROI temperature of 42.1 ± 0.3 °C. The T10 and T90 percentiles were 43.2 ± 0.4 °C and 41.0 ± 0.3 °C, respectively. For a 30-min treatment, the mean time duration between 41–45 °C was 31.1 min within the ROI. Conclusions The MRI-compatible HIFU system was successfully adapted to perform localised mild hyperthermia treatment in rodent models. A target temperature of 42 °C was well-maintained in a rat thigh model for 30 min. PMID:26540488
Maschmeyer, Ilka; Hasenberg, Tobias; Jaenicke, Annika; Lindner, Marcus; Lorenz, Alexandra Katharina; Zech, Julie; Garbe, Leif-Alexander; Sonntag, Frank; Hayden, Patrick; Ayehunie, Seyoum; Lauster, Roland; Marx, Uwe; Materne, Eva-Maria
2015-09-01
Systemic repeated dose safety assessment and systemic efficacy evaluation of substances are currently carried out on laboratory animals and in humans due to the lack of predictive alternatives. Relevant international regulations, such as OECD and ICH guidelines, demand long-term testing and oral, dermal, inhalation, and systemic exposure routes for such evaluations. So-called "human-on-a-chip" concepts are aiming to replace respective animals and humans in substance evaluation with miniaturized functional human organisms. The major technical hurdle toward success in this field is the life-like combination of human barrier organ models, such as intestine, lung or skin, with parenchymal organ equivalents, such as liver, at the smallest biologically acceptable scale. Here, we report on a reproducible homeostatic long-term co-culture of human liver equivalents with either a reconstructed human intestinal barrier model or a human skin biopsy applying a microphysiological system. We used a multi-organ chip (MOC) platform, which provides pulsatile fluid flow within physiological ranges at low media-to-tissue ratios. The MOC supports submerse cultivation of an intact intestinal barrier model and an air-liquid interface for the skin model during their co-culture with the liver equivalents respectively at (1)/100.000 the scale of their human counterparts in vivo. To increase the degree of organismal emulation, microfluidic channels of the liver-skin co-culture could be successfully covered with human endothelial cells, thus mimicking human vasculature, for the first time. Finally, exposure routes emulating oral and systemic administration in humans have been qualified by applying a repeated dose administration of a model substance - troglitazone - to the chip-based co-cultures. Copyright © 2015. Published by Elsevier B.V.
Kell, Douglas B
2013-12-01
Despite the sequencing of the human genome, the rate of innovative and successful drug discovery in the pharmaceutical industry has continued to decrease. Leaving aside regulatory matters, the fundamental and interlinked intellectual issues proposed to be largely responsible for this are: (a) the move from 'function-first' to 'target-first' methods of screening and drug discovery; (b) the belief that successful drugs should and do interact solely with single, individual targets, despite natural evolution's selection for biochemical networks that are robust to individual parameter changes; (c) an over-reliance on the rule-of-5 to constrain biophysical and chemical properties of drug libraries; (d) the general abandoning of natural products that do not obey the rule-of-5; (e) an incorrect belief that drugs diffuse passively into (and presumably out of) cells across the bilayers portions of membranes, according to their lipophilicity; (f) a widespread failure to recognize the overwhelmingly important role of proteinaceous transporters, as well as their expression profiles, in determining drug distribution in and between different tissues and individual patients; and (g) the general failure to use engineering principles to model biology in parallel with performing 'wet' experiments, such that 'what if?' experiments can be performed in silico to assess the likely success of any strategy. These facts/ideas are illustrated with a reasonably extensive literature review. Success in turning round drug discovery consequently requires: (a) decent systems biology models of human biochemical networks; (b) the use of these (iteratively with experiments) to model how drugs need to interact with multiple targets to have substantive effects on the phenotype; (c) the adoption of polypharmacology and/or cocktails of drugs as a desirable goal in itself; (d) the incorporation of drug transporters into systems biology models, en route to full and multiscale systems biology models that incorporate drug absorption, distribution, metabolism and excretion; (e) a return to 'function-first' or phenotypic screening; and (f) novel methods for inferring modes of action by measuring the properties on system variables at all levels of the 'omes. Such a strategy offers the opportunity of achieving a state where we can hope to predict biological processes and the effect of pharmaceutical agents upon them. Consequently, this should both lower attrition rates and raise the rates of discovery of effective drugs substantially. © 2013 The Author Journal compilation © 2013 FEBS.
Confronting the Issues of Programming in Information Systems Curricula: The Goal Is Success
ERIC Educational Resources Information Center
Babb, Jeffry; Longenecker, Herbert E., Jr.; Baugh, Jeanne; Feinstein, David
2014-01-01
Computer programming has been part of Information Systems (IS) curricula since the first model curriculum. It is with programming that computers are instructed how to implement our ideas into reality. Yet, over the last decade numbers of computing undergraduates have significantly declined in North American academic programs. In addition, high…
Understanding the business of employed physician practices.
Sanford, Kathleen D
2013-09-01
Health system leaders should understand issues related to finance, compliance, human resources, quality, and safety in their employed physician practices to better support the success of these practices. New business and payment models are driving operational changes in physician offices. Catholic Health Initiatives (CHI) has added new system roles and responsibilities to oversee physician practices.
Cryogenic Boil-Off Reduction System Testing
NASA Technical Reports Server (NTRS)
Plachta, David W.; Johnson, Wesley L.; Feller, Jeffery
2014-01-01
The Cryogenic Boil-Off Reduction System was tested with LH2 and LOX in a vacuum chamber to simulate space vacuum and the temperatures of low Earth orbit. Testing was successful and results validated the scaling study model that predicts active cooling reduces upper stage cryogenic propulsion mass for loiter periods greater than 2 weeks.
ERIC Educational Resources Information Center
Marek, Michael W.; Wu, Wen-Chi Vivian
2014-01-01
This conceptual, interdisciplinary inquiry explores Complex Dynamic Systems as the concept relates to the internal and external environmental factors affecting computer assisted language learning (CALL). Based on the results obtained by de Rosnay ["World Futures: The Journal of General Evolution", 67(4/5), 304-315 (2011)], who observed…
Topographic and soil influences on root productivity of three bioenergy cropping systems
Todd A. Ontl; Kirsten S. Hofmockel; Cynthia A. Cambardella; Lisa A. Schulte; Randall K. Kolka
2013-01-01
Successful modeling of the carbon (C) cycle requires empirical data regarding species-specific root responses to edaphic characteristics. We address this need by quantifying annual root production of three bioenergy systems (continuous corn, triticale/sorghum, switchgrass) in response to variation in soil properties across a toposequence within a Midwestern...
Human Systems Engineering: A Leadership Model for Collaboration and Change.
ERIC Educational Resources Information Center
Clark, Karen L.
Human systems engineering (HSE) was created to introduce a new way of viewing collaboration. HSE emphasizes the role of leaders who welcome risk, commit to achieving positive change, and help others achieve change. The principles of HSE and its successful application to the collaborative process were illustrated through a case study representing a…
The ABLe change framework: a conceptual and methodological tool for promoting systems change.
Foster-Fishman, Pennie G; Watson, Erin R
2012-06-01
This paper presents a new approach to the design and implementation of community change efforts like a System of Care. Called the ABLe Change Framework, the model provides simultaneous attention to the content and process of the work, ensuring effective implementation and the pursuit of systems change. Three key strategies are employed in this model to ensure the integration of content and process efforts and effective mobilization of broad scale systems change: Systemic Action Learning Teams, Simple Rules, and Small Wins. In this paper we describe the ABLe Change Framework and present a case study in which we successfully applied this approach to one system of care effort in Michigan.
NASA Technical Reports Server (NTRS)
Drake, R. L.; Duvoisin, P. F.; Asthana, A.; Mather, T. W.
1971-01-01
High speed automated identification and design of dynamic systems, both linear and nonlinear, are discussed. Special emphasis is placed on developing hardware and techniques which are applicable to practical problems. The basic modeling experiment and new results are described. Using the improvements developed successful identification of several systems, including a physical example as well as simulated systems, was obtained. The advantages of parameter signature analysis over signal signature analysis in go-no go testing of operational systems were demonstrated. The feasibility of using these ideas in failure mode prediction in operating systems was also investigated. An improved digital controlled nonlinear function generator was developed, de-bugged, and completely documented.
Modeling natural regeneration establishment in the northern Rocky Mountains of the U.S.A
D. E. Ferguson
1996-01-01
Retrospective examination of cutover forests enables the development of models that predict regeneration success as a function of plot conditions and time since disturbance. The modeling process uses a two-state system. In the first state, all plots are analyzed to predict the probability of stocking (at least one established seedling on the plot). In the second state...
Transforming Systems Engineering through Model-Centric Engineering
2018-02-28
intelligence (e.g., Artificial Intelligence , etc.), because they provide a means for representing knowledge. We see these capabilities coming to use in both...level, including: Performance is measured by degree of success of a mission Artificial Intelligence (AI) is applied to counterparties so that they...Modeling, Artificial Intelligence , Simulation and Modeling, 1989. [140] SAE ARP4761. Guidelines and Methods for Conducting the Safety Assessment Process
Risk Quantification of Systems Engineering Documents Improves Probability of DOD Project Success
2009-09-01
comprehensive risk model for DoD milestone review documentation as well as recommended changes to the Capability Maturity Model Integration ( CMMI ) Project...Milestone Documentation, Project Planning, Rational Frame, Political Frame, CMMI Project Planning Process Area, CMMI Risk Management Process Area...well as recommended changes to the Capability Maturity Model Integration ( CMMI ) Project Planning and Risk Management process areas. The intent is to
Comparison of two intraosseous infusion systems for adult emergency medical use.
Brenner, Thorsten; Bernhard, Michael; Helm, Matthias; Doll, Sara; Völkl, Alfred; Ganion, Nicole; Friedmann, Claudia; Sikinger, Marcus; Knapp, Jürgen; Martin, Eike; Gries, André
2008-09-01
The current guidelines of the European Resuscitation Council (ERC) stipulate that an intraosseous access should be placed if establishing a peripheral venous access for cardiopulmonary resuscitation (CPR) would involve delays. The aim of this study was therefore to compare a manual intraosseous infusion technique (MAN-IO) and a semi-automatic intraosseous infusion system (EZ-IO) using adult human cadavers as a model. After receiving verbal instruction and giving their written informed consent, the participants of the study were randomized into two groups (group I: MAN-IO, and group II: EZ-IO). In addition to the demographic data, the following were evaluated: (1) Number of attempts required to successfully place the infusion, (2) Insertion time, (3) Occurrence of technical complications and (4) User friendliness. Evaluation protocols from 84 study participants could be evaluated (MAN-IO: n=39 vs. EZ-IO: n=45). No significant differences were seen in the study participants' characteristics. Insertion times (MW+/-S.D.) of the respective successful attempts were comparable (MAN-IO: 33+/-28s vs. EZ-IO: 32+/-11s). When using the EZ-IO, the access was successfully established significantly more often on the first attempt (MAN-IO: 79.5% vs. EZ-IO: 97.8%; p<0.01). The EZ-IO was also found to have more advantages in terms of technical complications (MAN-IO: 15.4% vs. EZ-IO: 0.0%; p<0.01) and user friendliness (school grading system: MAN-IO: 1.9+/-0.7 vs. EZ-IO: 1.2+/-0.4; p<0.01). In an adult human cadaver model, the semi-automatic system was proven to be more effective. The EZ-IO gave more successful results, was associated with fewer technical complications, and is user friendlier.
NASA Technical Reports Server (NTRS)
Tegart, J. R.; Aydelott, J. C.
1978-01-01
The design of surface tension propellant acquisition systems using fine-mesh screen must take into account all factors that influence the liquid pressure differentials within the system. One of those factors is spacecraft vibration. Analytical models to predict the effects of vibration have been developed. A test program to verify the analytical models and to allow a comparative evaluation of the parameters influencing the response to vibration was performed. Screen specimens were tested under conditions simulating the operation of an acquisition system, considering the effects of such parameters as screen orientation and configuration, screen support method, screen mesh, liquid flow and liquid properties. An analytical model, based on empirical coefficients, was most successful in predicting the effects of vibration.
A situation-response model for intelligent pilot aiding
NASA Technical Reports Server (NTRS)
Schudy, Robert; Corker, Kevin
1987-01-01
An intelligent pilot aiding system needs models of the pilot information processing to provide the computational basis for successful cooperation between the pilot and the aiding system. By combining artificial intelligence concepts with the human information processing model of Rasmussen, an abstraction hierarchy of states of knowledge, processing functions, and shortcuts are developed, which is useful for characterizing the information processing both of the pilot and of the aiding system. This approach is used in the conceptual design of a real time intelligent aiding system for flight crews of transport aircraft. One promising result was the tentative identification of a particular class of information processing shortcuts, from situation characterizations to appropriate responses, as the most important reliable pathway for dealing with complex time critical situations.
Wang, Gang; Briskot, Till; Hahn, Tobias; Baumann, Pascal; Hubbuch, Jürgen
2017-03-03
Mechanistic modeling has been repeatedly successfully applied in process development and control of protein chromatography. For each combination of adsorbate and adsorbent, the mechanistic models have to be calibrated. Some of the model parameters, such as system characteristics, can be determined reliably by applying well-established experimental methods, whereas others cannot be measured directly. In common practice of protein chromatography modeling, these parameters are identified by applying time-consuming methods such as frontal analysis combined with gradient experiments, curve-fitting, or combined Yamamoto approach. For new components in the chromatographic system, these traditional calibration approaches require to be conducted repeatedly. In the presented work, a novel method for the calibration of mechanistic models based on artificial neural network (ANN) modeling was applied. An in silico screening of possible model parameter combinations was performed to generate learning material for the ANN model. Once the ANN model was trained to recognize chromatograms and to respond with the corresponding model parameter set, it was used to calibrate the mechanistic model from measured chromatograms. The ANN model's capability of parameter estimation was tested by predicting gradient elution chromatograms. The time-consuming model parameter estimation process itself could be reduced down to milliseconds. The functionality of the method was successfully demonstrated in a study with the calibration of the transport-dispersive model (TDM) and the stoichiometric displacement model (SDM) for a protein mixture. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
Performance analysis of successive over relaxation method for solving glioma growth model
NASA Astrophysics Data System (ADS)
Hussain, Abida; Faye, Ibrahima; Muthuvalu, Mohana Sundaram
2016-11-01
Brain tumor is one of the prevalent cancers in the world that lead to death. In light of the present information of the properties of gliomas, mathematical models have been developed by scientists to quantify the proliferation and invasion dynamics of glioma. In this study, one-dimensional glioma growth model is considered, and finite difference method is used to discretize the problem. Then, two stationary methods, namely Gauss-Seidel (GS) and Successive Over Relaxation (SOR) are used to solve the governing algebraic system. The performance of the methods are evaluated in terms of number of iteration and computational time. On the basis of performance analysis, SOR method is shown to be more superior compared to GS method.
Observation planning tools for the ESO VLT interferometer
NASA Astrophysics Data System (ADS)
McKay, Derek J.; Ballester, Pascal; Vinther, Jakob
2004-09-01
Now that the Very Large Telescope Interferometer (VLTI) is producing regular scientific observations, the field of optical interferometry has moved from being a specialist niche area into mainstream astronomy. Making such instruments available to the general community involves difficult challenges in modelling, presentation and automation. The planning of each interferometric observation requires calibrator source selection, visibility prediction, signal-to-noise estimation and exposure time calculation. These planning tools require detailed physical models simulating the complete telescope system - including the observed source, atmosphere, array configuration, optics, detector and data processing. Only then can these software utilities provide accurate predictions about instrument performance, robust noise estimation and reliable metrics indicating the anticipated success of an observation. The information must be presented in a clear, intelligible manner, sufficiently abstract to hide the details of telescope technicalities, but still giving the user a degree of control over the system. The Data Flow System group has addressed the needs of the VLTI and, in doing so, has gained some new insights into the planning of observations, and the modelling and simulation of interferometer performance. This paper reports these new techniques, as well as the successes of the Data Flow System group in this area and a summary of what is now offered as standard to VLTI observers.
Spray Bar Zero-Gravity Vent System for On-Orbit Liquid Hydrogen Storage
NASA Technical Reports Server (NTRS)
Hastings, L. J.; Flachbart, R. H.; Martin, J. J.; Hedayat, A.; Fazah, M.; Lak, T.; Nguyen, H.; Bailey, J. W.
2003-01-01
During zero-gravity orbital cryogenic propulsion operations, a thermodynamic vent system (TVS) concept is expected to maintain tank pressure control without propellant resettling. In this case, a longitudinal spray bar mixer system, coupled with a Joule-Thompson (J-T) valve and heat exchanger, was evaluated in a series of TVS tests using the 18 cu m multipurpose hydrogen test bed. Tests performed at fill levels of 90, 50, and 25 percent, coupled with heat tank leaks of about 20 and 50 W, successfully demonstrated tank pressure control within a 7-kPa band. Based on limited testing, the presence of helium constrained the energy exchange between the gaseous and liquid hydrogen (LH2) during the mixing cycles. A transient analytical model, formulated to characterize TVS performance, was used to correlate the test data. During self-pressurization cycles following tank lockup, the model predicted faster pressure rise rates than were measured; however, once the system entered the cyclic self-pressurization/mixing/venting operational mode, the modeled and measured data were quite similar. During a special test at the 25-percent fill level, the J-T valve was allowed to remain open and successfully reduced the bulk LH2 saturation pressure from 133 to 70 kPa in 188 min.
Development of a piezo-actuated micro-teleoperation system for cell manipulation.
Zareinejad, M; Rezaei, S M; Abdullah, A; Shiry Ghidary, S
2009-03-01
Intracytoplasmic sperm injection (ICSI) requires long training and has low success rates, primarily due to poor control over the injection force. Making force feedback available to the operator will improve the success rate of the injection task. A macro-micro-teleoperation system bridges the gap between the task performed at the micro-level and the macroscopic movements of the operator. The teleoperation slave manipulator should accurately position a needle to precisely penetrate a cell membrane. Piezoelectric actuators are widely used in micromanipulation applications; however, hysteresis non-linearity limits the accuracy of these actuators. This paper presents a novel approach for utilizing a piezoelectric nano-stage as slave manipulator of a teleoperation system. The Prandtl-Ishlinskii (PI) model is used to model actuator hysteresis in a feedforward scheme to cancel out this non-linearity. To deal with the influence of parametric uncertainties, unmodelled dynamics and PI identification error, a perturbation term is added to the slave model and applies a sliding mode-based impedance control with perturbation estimation. The stability of entire system is guaranteed by Llewellyn's absolute stability criterion. The performance of the proposed controller was investigated through experiments for cell membrane penetration. The experimental results verified the accurate position tracking in free motion and simultaneous position and force tracking in contact with a low stiffness environment.
Conrads, Paul; Roehl, Edwin A.; Daamen, Ruby C.; Kitchens, Wiley M.
2006-01-01
The Savannah Harbor is one of the busiest ports on the East Coast of the United States and is located downstream from the Savannah National Wildlife Refuge, which is one of the Nation?s largest freshwater tidal marshes. The Georgia Ports Authority and the U.S. Army Corps of Engineers funded hydrodynamic and ecological studies to evaluate the potential effects of a proposed deepening of Savannah Harbor as part of the Environmental Impact Statement. These studies included a three-dimensional (3D) model of the Savannah River estuary system, which was developed to simulate changes in water levels and salinity in the system in response to geometry changes as a result of the deepening of Savannah Harbor, and a marsh-succession model that predicts plant distribution in the tidal marshes in response to changes in the water-level and salinity conditions in the marsh. Beginning in May 2001, the U.S. Geological Survey entered into cooperative agreements with the Georgia Ports Authority to develop empirical models to simulate the water level and salinity of the rivers and tidal marshes in the vicinity of the Savannah National Wildlife Refuge and to link the 3D hydrodynamic river-estuary model and the marsh-succession model. For the development of these models, many different databases were created that describe the complexity and behaviors of the estuary. The U.S. Geological Survey has maintained a network of continuous streamflow, water-level, and specific-conductance (field measurement to compute salinity) river gages in the study area since the 1980s and a network of water-level and salinity marsh gages in the study area since 1999. The Georgia Ports Authority collected water-level and salinity data during summer 1997 and 1999 and collected continuous water-level and salinity data in the marsh and connecting tidal creeks from 1999 to 2002. Most of the databases comprise time series that differ by variable type, periods of record, measurement frequency, location, and reliability. Understanding freshwater inflows, tidal water levels, and specific conductance in the rivers and marshes is critical to enhancing the predictive capabilities of a successful marsh succession model. Data-mining techniques, including artificial neural network (ANN) models, were applied to address various needs of the ecology study and to integrate the riverine predictions from the 3D model to the marsh-succession model. ANN models were developed to simulate riverine water levels and specific conductance in the vicinity of the tidal marshes for the full range of historical conditions using data from the river gaging networks. ANN models were also developed to simulate the marsh water levels and pore-water salinities using data from the marsh gaging networks. Using the marsh ANN models, the continuous marsh network was hindcasted to be concurrent with the long-term riverine network. The hindcasted data allow ecologists to compute hydrologic parameters?such as hydroperiods and exposure frequency?to help analyze historical vegetation data. To integrate the 3D hydrodynamic model, the marsh-succession model, and various time-series databases, a decision support system (DSS) was developed to support the various needs of regulatory and scientific stakeholders. The DSS required the development of a spreadsheet application that integrates the database, 3D hydrodynamic model output, and ANN riverine and marsh models into a single package that is easy to use and can be readily disseminated. The DSS allows users to evaluate water-level and salinity response for different hydrologic conditions. Savannah River streamflows can be controlled by the user as constant flow, a percentage of historical flows, a percentile daily flow hydrograph, or as a user-specified hydrograph. The DSS can also use output from the 3D model at stream gages near the Savannah National Wildlife Refuge to simulate the effects in the tidal marshes. The DSS is distributed with a two-dimensional (
Recent tests of the equilibrium-point hypothesis (lambda model).
Feldman, A G; Ostry, D J; Levin, M F; Gribble, P L; Mitnitski, A B
1998-07-01
The lambda model of the equilibrium-point hypothesis (Feldman & Levin, 1995) is an approach to motor control which, like physics, is based on a logical system coordinating empirical data. The model has gone through an interesting period. On one hand, several nontrivial predictions of the model have been successfully verified in recent studies. In addition, the explanatory and predictive capacity of the model has been enhanced by its extension to multimuscle and multijoint systems. On the other hand, claims have recently appeared suggesting that the model should be abandoned. The present paper focuses on these claims and concludes that they are unfounded. Much of the experimental data that have been used to reject the model are actually consistent with it.
Efficient CRISPR/Cas9-based genome editing in carrot cells.
Klimek-Chodacka, Magdalena; Oleszkiewicz, Tomasz; Lowder, Levi G; Qi, Yiping; Baranski, Rafal
2018-04-01
The first report presenting successful and efficient carrot genome editing using CRISPR/Cas9 system. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated (Cas9) is a powerful genome editing tool that has been widely adopted in model organisms recently, but has not been used in carrot-a model species for in vitro culture studies and an important health-promoting crop grown worldwide. In this study, for the first time, we report application of the CRISPR/Cas9 system for efficient targeted mutagenesis of the carrot genome. Multiplexing CRISPR/Cas9 vectors expressing two single-guide RNA (gRNAs) targeting the carrot flavanone-3-hydroxylase (F3H) gene were tested for blockage of the anthocyanin biosynthesis in a model purple-colored callus using Agrobacterium-mediated genetic transformation. This approach allowed fast and visual comparison of three codon-optimized Cas9 genes and revealed that the most efficient one in generating F3H mutants was the Arabidopsis codon-optimized AteCas9 gene with up to 90% efficiency. Knockout of F3H gene resulted in the discoloration of calli, validating the functional role of this gene in the anthocyanin biosynthesis in carrot as well as providing a visual marker for screening successfully edited events. Most resulting mutations were small Indels, but long chromosome fragment deletions of 116-119 nt were also generated with simultaneous cleavage mediated by two gRNAs. The results demonstrate successful site-directed mutagenesis in carrot with CRISPR/Cas9 and the usefulness of a model callus culture to validate genome editing systems. Given that the carrot genome has been sequenced recently, our timely study sheds light on the promising application of genome editing tools for boosting basic and translational research in this important vegetable crop.
Forecasting Austrian national elections: The Grand Coalition model
Aichholzer, Julian; Willmann, Johanna
2014-01-01
Forecasting the outcomes of national elections has become established practice in several democracies. In the present paper, we develop an economic voting model for forecasting the future success of the Austrian ‘grand coalition’, i.e., the joint electoral success of the two mainstream parties SPOE and OEVP, at the 2013 Austrian Parliamentary Elections. Our main argument is that the success of both parties is strongly tied to the accomplishments of the Austrian system of corporatism, that is, the Social Partnership (Sozialpartnerschaft), in providing economic prosperity. Using data from Austrian national elections between 1953 and 2008 (n=18), we rely on the following predictors in our forecasting model: (1) unemployment rates, (2) previous incumbency of the two parties, and (3) dealignment over time. We conclude that, in general, the two mainstream parties benefit considerably from low unemployment rates, and are weakened whenever they have previously formed a coalition government. Further, we show that they have gradually been losing a good share of their voter basis over recent decades. PMID:26339109
Charge redistribution in QM:QM ONIOM model systems: a constrained density functional theory approach
NASA Astrophysics Data System (ADS)
Beckett, Daniel; Krukau, Aliaksandr; Raghavachari, Krishnan
2017-11-01
The ONIOM hybrid method has found considerable success in QM:QM studies designed to approximate a high level of theory at a significantly reduced cost. This cost reduction is achieved by treating only a small model system with the target level of theory and the rest of the system with a low, inexpensive, level of theory. However, the choice of an appropriate model system is a limiting factor in ONIOM calculations and effects such as charge redistribution across the model system boundary must be considered as a source of error. In an effort to increase the general applicability of the ONIOM model, a method to treat the charge redistribution effect is developed using constrained density functional theory (CDFT) to constrain the charge experienced by the model system in the full calculation to the link atoms in the truncated model system calculations. Two separate CDFT-ONIOM schemes are developed and tested on a set of 20 reactions with eight combinations of levels of theory. It is shown that a scheme using a scaled Lagrange multiplier term obtained from the low-level CDFT model calculation outperforms ONIOM at each combination of levels of theory from 32% to 70%.
Simulating ungulate herbivory across forest landscapes: A browsing extension for LANDIS-II
DeJager, Nathan R.; Drohan, Patrick J.; Miranda, Brian M.; Sturtevant, Brian R.; Stout, Susan L.; Royo, Alejandro; Gustafson, Eric J.; Romanski, Mark C.
2017-01-01
Browsing ungulates alter forest productivity and vegetation succession through selective foraging on species that often dominate early succession. However, the long-term and large-scale effects of browsing on forest succession are not possible to project without the use of simulation models. To explore the effects of ungulates on succession in a spatially explicit manner, we developed a Browse Extension that simulates the effects of browsing ungulates on the growth and survival of plant species cohorts within the LANDIS-II spatially dynamic forest landscape simulation model framework. We demonstrate the capabilities of the new extension and explore the spatial effects of ungulates on forest composition and dynamics using two case studies. The first case study examined the long-term effects of persistently high white-tailed deer browsing rates in the northern hardwood forests of the Allegheny National Forest, USA. In the second case study, we incorporated a dynamic ungulate population model to simulate interactions between the moose population and boreal forest landscape of Isle Royale National Park, USA. In both model applications, browsing reduced total aboveground live biomass and caused shifts in forest composition. Simulations that included effects of browsing resulted in successional patterns that were more similar to those observed in the study regions compared to simulations that did not incorporate browsing effects. Further, model estimates of moose population density and available forage biomass were similar to previously published field estimates at Isle Royale and in other moose-boreal forest systems. Our simulations suggest that neglecting effects of browsing when modeling forest succession in ecosystems known to be influenced by ungulates may result in flawed predictions of aboveground biomass and tree species composition.
Study on HOPE Management Mode of Coal Enterprises Based on Systematic Thinking
NASA Astrophysics Data System (ADS)
Zhaoran, Zhang; Tianzhu, Zhang; Wenjing, Tong
2018-02-01
The extensive management mode of coal enterprises is no longer applicable to the demand of enterprise development under the new economic situation. Combined with the characteristics of coal mine production, based on the system of thinking, integration of lean, people, comprehensive, job management theory, formed HOPE management model, including a core system and three support systems and 18 elements. There are three stages in the development and implementation of this model. To 6S site management for the initial stage to job process reengineering for the intermediate stage to post value process control for the advanced stage. The successful implementation of HOPE model in coal enterprises needs comprehensive control from five aspects: lean culture construction, flattening organizational structure, cost control system, performance appraisal system and lean information management platform. HOPE model can be implemented smoothly and make “win-win” between enterprises and employees.
NASA Astrophysics Data System (ADS)
Orra, Kashfull; Choudhury, Sounak K.
2016-12-01
The purpose of this paper is to build an adaptive feedback linear control system to check the variation of cutting force signal to improve the tool life. The paper discusses the use of transfer function approach in improving the mathematical modelling and adaptively controlling the process dynamics of the turning operation. The experimental results shows to be in agreement with the simulation model and error obtained is less than 3%. The state space approach model used in this paper successfully check the adequacy of the control system through controllability and observability test matrix and can be transferred from one state to another by appropriate input control in a finite time. The proposed system can be implemented to other machining process under varying range of cutting conditions to improve the efficiency and observability of the system.
Goal-Function Tree Modeling for Systems Engineering and Fault Management
NASA Technical Reports Server (NTRS)
Patterson, Jonathan D.; Johnson, Stephen B.
2013-01-01
The draft NASA Fault Management (FM) Handbook (2012) states that Fault Management (FM) is a "part of systems engineering", and that it "demands a system-level perspective" (NASAHDBK- 1002, 7). What, exactly, is the relationship between systems engineering and FM? To NASA, systems engineering (SE) is "the art and science of developing an operable system capable of meeting requirements within often opposed constraints" (NASA/SP-2007-6105, 3). Systems engineering starts with the elucidation and development of requirements, which set the goals that the system is to achieve. To achieve these goals, the systems engineer typically defines functions, and the functions in turn are the basis for design trades to determine the best means to perform the functions. System Health Management (SHM), by contrast, defines "the capabilities of a system that preserve the system's ability to function as intended" (Johnson et al., 2011, 3). Fault Management, in turn, is the operational subset of SHM, which detects current or future failures, and takes operational measures to prevent or respond to these failures. Failure, in turn, is the "unacceptable performance of intended function." (Johnson 2011, 605) Thus the relationship of SE to FM is that SE defines the functions and the design to perform those functions to meet system goals and requirements, while FM detects the inability to perform those functions and takes action. SHM and FM are in essence "the dark side" of SE. For every function to be performed (SE), there is the possibility that it is not successfully performed (SHM); FM defines the means to operationally detect and respond to this lack of success. We can also describe this in terms of goals: for every goal to be achieved, there is the possibility that it is not achieved; FM defines the means to operationally detect and respond to this inability to achieve the goal. This brief description of relationships between SE, SHM, and FM provide hints to a modeling approach to provide formal connectivity between the nominal (SE), and off-nominal (SHM and FM) aspects of functions and designs. This paper describes a formal modeling approach to the initial phases of the development process that integrates the nominal and off-nominal perspectives in a model that unites SE goals and functions of with the failure to achieve goals and functions (SHM/FM). This methodology and corresponding model, known as a Goal-Function Tree (GFT), provides a means to represent, decompose, and elaborate system goals and functions in a rigorous manner that connects directly to design through use of state variables that translate natural language requirements and goals into logical-physical state language. The state variable-based approach also provides the means to directly connect FM to the design, by specifying the range in which state variables must be controlled to achieve goals, and conversely, the failures that exist if system behavior go out-of-range. This in turn allows for the systems engineers and SHM/FM engineers to determine which state variables to monitor, and what action(s) to take should the system fail to achieve that goal. In sum, the GFT representation provides a unified approach to early-phase SE and FM development. This representation and methodology has been successfully developed and implemented using Systems Modeling Language (SysML) on the NASA Space Launch System (SLS) Program. It enabled early design trade studies of failure detection coverage to ensure complete detection coverage of all crew-threatening failures. The representation maps directly both to FM algorithm designs, and to failure scenario definitions needed for design analysis and testing. The GFT representation provided the basis for mapping of abort triggers into scenarios, both needed for initial, and successful quantitative analyses of abort effectiveness (detection and response to crew-threatening events).
Fiehe, Sandra; Wagner, Georg; Schlanstein, Peter; Rosefort, Christiane; Kopp, Rüdger; Bensberg, Ralf; Knipp, Peter; Schmitz-Rode, Thomas; Steinseifer, Ulrich; Arens, Jutta
2014-04-01
The ultimate objective of university research and development projects is usually to create knowledge, but also to successfully transfer results to industry for subsequent marketing. We hypothesized that the university technology transfer requires efficient measures to improve this important step. Besides good scientific practice, foresighted and industry-specific adapted documentation of research processes in terms of a quality management system might improve the technology transfer. In order to bridge the gap between research institute and cooperating industry, a model project has been accompanied by a project specific amount of quality management. However, such a system had to remain manageable and must not constrain the researchers' creativity. Moreover, topics and research team are strongly interdisciplinary, which entails difficulties regarding communication because of different perspectives and terminology. In parallel to the technical work of the model project, an adaptable quality management system with a quality manual, defined procedures, and forms and documents accompanying the research, development and validation was implemented. After process acquisition and analysis the appropriate amount of management for the model project was identified by a self-developed rating system considering project characteristics like size, innovation, stakeholders, interdisciplinarity, etc. Employees were trained according to their needs. The management was supported and the technical documentation was optimized. Finally, the quality management system has been transferred successfully to further projects.
Elements of active vibration control for rotating machinery
NASA Technical Reports Server (NTRS)
Ulbrich, Heinz
1990-01-01
The success or failure of active vibration control is determined by the availability of suitable actuators, modeling of the entire system including all active elements, positioning of the actuators and sensors, and implementation of problem-adapted control concepts. All of these topics are outlined and their special problems are discussed in detail. Special attention is given to efficient modeling of systems, especially for considering the active elements. Finally, design methods for and the application of active vibration control on rotating machinery are demonstrated by several real applications.
A path-integral approach to the problem of time
NASA Astrophysics Data System (ADS)
Amaral, M. M.; Bojowald, Martin
2018-01-01
Quantum transition amplitudes are formulated for model systems with local internal time, using intuition from path integrals. The amplitudes are shown to be more regular near a turning point of internal time than could be expected based on existing canonical treatments. In particular, a successful transition through a turning point is provided in the model systems, together with a new definition of such a transition in general terms. Some of the results rely on a fruitful relation between the problem of time and general Gribov problems.
Tool Efficiency Analysis model research in SEMI industry
NASA Astrophysics Data System (ADS)
Lei, Ma; Nana, Zhang; Zhongqiu, Zhang
2018-06-01
One of the key goals in SEMI industry is to improve equipment through put and ensure equipment production efficiency maximization. This paper is based on SEMI standards in semiconductor equipment control, defines the transaction rules between different tool states, and presents a TEA system model which is to analysis tool performance automatically based on finite state machine. The system was applied to fab tools and verified its effectiveness successfully, and obtained the parameter values used to measure the equipment performance, also including the advices of improvement.
Components of nurse innovation: a model from acute care hospitals.
Neidlinger, S H; Drews, N; Hukari, D; Bartleson, B J; Abbott, F K; Harper, R; Lyon, J
1992-12-01
Components that promote nurse innovation in acute care hospitals are explicated in the Acute Care Nursing Innovation Model. Grounded in nursing care delivery systems and excellent management-organizations perspectives, nurse executives and 30 nurse "intrapreneurs" from 10 innovative hospitals spanning the United States shared their experiences and insights through semistructured, tape-recorded telephone interviews. Guided by interpretive interactionist strategies, the essential components, characteristics, and interrelationships are conceptualized and described so that others may be successful in their innovative endeavors. Successful innovation is dependent on the fit between and among the components; the better the fit, the more likely the innovation will succeed.
Vollherbst, D F; Sommer, C M; Ulfert, C; Pfaff, J; Bendszus, M; Möhlenbruch, M A
2017-07-01
Embolization plays a key role in the treatment of arteriovenous malformations. The aim of this study was to evaluate an established (Onyx) and a novel (precipitating hydrophobic injectable liquid [PHIL]) liquid embolic agent in an in vitro AVM model. An AVM model was integrated into a circuit system. The artificial nidus (subdivided into 28 honeycomb-like sections) was embolized with Onyx 18 (group Onyx; n = 8) or PHIL 25 (group PHIL; n = 8) with different pause times between the injections (30 and 60 seconds, n = 4 per study group) by using a 1.3F microcatheter. Procedure times, number of injections, embolization success (defined as the number of filled sections of the artificial nidus), volume of embolic agent, and frequency and extent of reflux and draining vein embolization were assessed. Embolization success was comparable between Onyx and PHIL. Shorter pause times resulted in a significantly higher embolization success for PHIL (median embolization score, 28 versus 18; P = .011). Compared with Onyx, lower volumes of PHIL were required for the same extent of embolization (median volume per section of the artificial nidus, 15.5 versus 3.6 μL; P < .001). While the embolization success was comparable for Onyx and PHIL, pause time had a considerable effect on the embolization success in an in vitro AVM model. Compared with Onyx, lower volumes of PHIL were required for the same extent of embolization. © 2017 by American Journal of Neuroradiology.
Heckbert, Scott; Wilson, Jeffrey J.; Vandenbroeck, Andrew J. K.; Cranston, Jerome; Farr, Daniel R.
2016-01-01
The science of ecosystem service (ES) mapping has become increasingly sophisticated over the past 20 years, and examples of successfully integrating ES into management decisions at national and sub-national scales have begun to emerge. However, increasing model sophistication and accuracy—and therefore complexity—may trade-off with ease of use and applicability to real-world decision-making contexts, so it is vital to incorporate the lessons learned from implementation efforts into new model development. Using successful implementation efforts for guidance, we developed an integrated ES modelling system to quantify several ecosystem services: forest timber production and carbon storage, water purification, pollination, and biodiversity. The system is designed to facilitate uptake of ES information into land-use decisions through three principal considerations: (1) using relatively straightforward models that can be readily deployed and interpreted without specialized expertise; (2) using an agent-based modelling framework to enable the incorporation of human decision-making directly within the model; and (3) integration among all ES models to simultaneously demonstrate the effects of a single land-use decision on multiple ES. We present an implementation of the model for a major watershed in Alberta, Canada, and highlight the system’s capabilities to assess a suite of ES under future management decisions, including forestry activities under two alternative timber harvest strategies, and through a scenario modelling analysis exploring different intensities of hypothetical agricultural expansion. By using a modular approach, the modelling system can be readily expanded to evaluate additional ecosystem services or management questions of interest in order to guide land-use decisions to achieve socioeconomic and environmental objectives. PMID:28028479
Microphone Array Phased Processing System (MAPPS): Version 4.0 Manual
NASA Technical Reports Server (NTRS)
Watts, Michael E.; Mosher, Marianne; Barnes, Michael; Bardina, Jorge
1999-01-01
A processing system has been developed to meet increasing demands for detailed noise measurement of individual model components. The Microphone Array Phased Processing System (MAPPS) uses graphical user interfaces to control all aspects of data processing and visualization. The system uses networked parallel computers to provide noise maps at selected frequencies in a near real-time testing environment. The system has been successfully used in the NASA Ames 7- by 10-Foot Wind Tunnel.
Promoting evaluation capacity building in a complex adaptive system.
Lawrenz, Frances; Kollmann, Elizabeth Kunz; King, Jean A; Bequette, Marjorie; Pattison, Scott; Nelson, Amy Grack; Cohn, Sarah; Cardiel, Christopher L B; Iacovelli, Stephanie; Eliou, Gayra Ostgaard; Goss, Juli; Causey, Lauren; Sinkey, Anne; Beyer, Marta; Francisco, Melanie
2018-04-10
This study provides results from an NSF funded, four year, case study about evaluation capacity building in a complex adaptive system, the Nanoscale Informal Science Education Network (NISE Net). The results of the Complex Adaptive Systems as a Model for Network Evaluations (CASNET) project indicate that complex adaptive system concepts help to explain evaluation capacity building in a network. The NISE Network was found to be a complex learning system that was supportive of evaluation capacity building through feedback loops that provided for information sharing and interaction. Participants in the system had different levels of and sources of evaluation knowledge. To be successful at building capacity, the system needed to have a balance between both centralized and decentralized control, coherence, redundancy, and diversity. Embeddedness of individuals within the system also provided support and moved the capacity of the system forward. Finally, success depended on attention being paid to the control of resources. Implications of these findings are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.
Magnetic suspension and balance system advanced study, phase 2
NASA Technical Reports Server (NTRS)
Boom, R. W.; Abdelsalam, M. K.; Eyssa, Y. M.; Mcintosh, G. E.
1990-01-01
The design improvements for the system encompass 14 or 18 external superconductive coils mounted on a 8 x 8 foot wind tunnel, a superconductive model core magnet on a holmium mandrel to fit an F-16 model, model wings of permanent magnet material Nd2Fe14B, and fiber glass epoxy structure. The Magnetic Suspension and Balance System (MSBS) advanced design is confirmed by the successful construction and test of a full size superconductive model core solenoid with holmium mandrel. The solenoid is 75 cm long and 12.6 cm in diameter and produces 6.1 tesla for a hold time of 47 minutes. An integrated coil system design of a new compact configuration without specific coils for roll or pitch shows promise of simplicity; magnet reductions of 30 percent compared to the most recent 1985 design are possible.
Blood and small intestine cell kinetics under radiation exposures: Mathematical modeling
NASA Astrophysics Data System (ADS)
Smirnova, Olga
Biophysical models, which describe the dynamics of vital body systems (namely, hematopoiesis and small intestinal epithelium) in mammals exposed to acute and chronic radiation, are developed. These models, based on conventional biological theories, are realized as the systems of nonlinear differential equations. Their variables and constant parameters have real biological meaning, that provides successful identification and verification of the models in hand. The explanation of a number of radiobiological effects, including those of the low-level long-term exposures, is proposed proceeding from the modeling results. It is proved that the predictions the models agree with the respective experimental data at both qualitative and quantitative levels. All this testifies to the efficiency of employment of the developed models in investigation and prediction of radiation effects on the hematopoietic and small intestinal epithelium systems, that can be used for the radiation risk assessment in the long-term space missions such as lunar colony and Mars voyage.
Retrosynthetic Reaction Prediction Using Neural Sequence-to-Sequence Models
2017-01-01
We describe a fully data driven model that learns to perform a retrosynthetic reaction prediction task, which is treated as a sequence-to-sequence mapping problem. The end-to-end trained model has an encoder–decoder architecture that consists of two recurrent neural networks, which has previously shown great success in solving other sequence-to-sequence prediction tasks such as machine translation. The model is trained on 50,000 experimental reaction examples from the United States patent literature, which span 10 broad reaction types that are commonly used by medicinal chemists. We find that our model performs comparably with a rule-based expert system baseline model, and also overcomes certain limitations associated with rule-based expert systems and with any machine learning approach that contains a rule-based expert system component. Our model provides an important first step toward solving the challenging problem of computational retrosynthetic analysis. PMID:29104927
Alshurafa, Nabil; Eastwood, Jo-Ann; Pourhomayoun, Mohammad; Liu, Jason J; Sarrafzadeh, Majid
2014-01-01
Current studies have produced a plethora of remote health monitoring (RHM) systems designed to enhance the care of patients with chronic diseases. Many RHM systems are designed to improve patient risk factors for cardiovascular disease, including physiological parameters such as body mass index (BMI) and waist circumference, and lipid profiles such as low density lipoprotein (LDL) and high density lipoprotein (HDL). There are several patient characteristics that could be determining factors for a patient's RHM outcome success, but these characteristics have been largely unidentified. In this paper, we analyze results from an RHM system deployed in a six month Women's Heart Health study of 90 patients, and apply advanced feature selection and machine learning algorithms to identify patients' key baseline contextual features and build effective prediction models that help determine RHM outcome success. We introduce Wanda-CVD, a smartphone-based RHM system designed to help participants with cardiovascular disease risk factors by motivating participants through wireless coaching using feedback and prompts as social support. We analyze key contextual features that secure positive patient outcomes in both physiological parameters and lipid profiles. Results from the Women's Heart Health study show that health threat of heart disease, quality of life, family history, stress factors, social support, and anxiety at baseline all help predict patient RHM outcome success.
Information for Successful Interaction with Autonomous Systems
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Johnson, Kathy A.
2003-01-01
Interaction in heterogeneous mission operations teams is not well matched to classical models of coordination with autonomous systems. We describe methods of loose coordination and information management in mission operations. We describe an information agent and information management tool suite for managing information from many sources, including autonomous agents. We present an integrated model of levels of complexity of agent and human behavior, which shows types of information processing and points of potential error in agent activities. We discuss the types of information needed for diagnosing problems and planning interactions with an autonomous system. We discuss types of coordination for which designs are needed for autonomous system functions.
A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process
NASA Technical Reports Server (NTRS)
Wang, Yi; Tamai, Tetsuo
2009-01-01
Since the complexity of software systems continues to grow, most engineers face two serious problems: the state space explosion problem and the problem of how to debug systems. In this paper, we propose a game-theoretic approach to full branching time model checking on three-valued semantics. The three-valued models and logics provide successful abstraction that overcomes the state space explosion problem. The game style model checking that generates counter-examples can guide refinement or identify validated formulas, which solves the system debugging problem. Furthermore, output of our game style method will give significant information to engineers in detecting where errors have occurred and what the causes of the errors are.
Thermodynamics and combustion modeling
NASA Technical Reports Server (NTRS)
Zeleznik, Frank J.
1986-01-01
Modeling fluid phase phenomena blends the conservation equations of continuum mechanics with the property equations of thermodynamics. The thermodynamic contribution becomes especially important when the phenomena involve chemical reactions as they do in combustion systems. The successful study of combustion processes requires (1) the availability of accurate thermodynamic properties for both the reactants and the products of reaction and (2) the computational capabilities to use the properties. A discussion is given of some aspects of the problem of estimating accurate thermodynamic properties both for reactants and products of reaction. Also, some examples of the use of thermodynamic properties for modeling chemically reacting systems are presented. These examples include one-dimensional flow systems and the internal combustion engine.
A Neural Network Approach to Intention Modeling for User-Adapted Conversational Agents
Griol, David
2016-01-01
Spoken dialogue systems have been proposed to enable a more natural and intuitive interaction with the environment and human-computer interfaces. In this contribution, we present a framework based on neural networks that allows modeling of the user's intention during the dialogue and uses this prediction to dynamically adapt the dialogue model of the system taking into consideration the user's needs and preferences. We have evaluated our proposal to develop a user-adapted spoken dialogue system that facilitates tourist information and services and provide a detailed discussion of the positive influence of our proposal in the success of the interaction, the information and services provided, and the quality perceived by the users. PMID:26819592
NASA Technical Reports Server (NTRS)
Scott, W. A.
1984-01-01
The propulsion simulator calibration laboratory (PSCL) in which calibrations can be performed to determine the gross thrust and airflow of propulsion simulators installed in wind tunnel models is described. The preliminary checkout, evaluation and calibration of the PSCL's 3 component force measurement system is reported. Methods and equipment were developed for the alignment and calibration of the force measurement system. The initial alignment of the system demonstrated the need for more efficient means of aligning system's components. The use of precision alignment jigs increases both the speed and accuracy with which the system is aligned. The calibration of the force measurement system shows that the methods and equipment for this procedure can be successful.
2014-10-01
Working in a SoS M&S enterprise emphasizing affordability and simulation asset reuse, we drew from our “lessons learned ” the conclusion that M&S “IU” must...those les- sons learned and programmatic risks we encountered motivates our recommendation for formalizing SoS M&S IU definition and specification in a...especially in system- of-system contexts, such as the Ballistic Missile Defense System. Leveraging lessons learned from intense reliance on system-of
Bringing Chatbots into education: Towards Natural Language Negotiation of Open Learner Models
NASA Astrophysics Data System (ADS)
Kerlyl, Alice; Hall, Phil; Bull, Susan
There is an extensive body of work on Intelligent Tutoring Systems: computer environments for education, teaching and training that adapt to the needs of the individual learner. Work on personalisation and adaptivity has included research into allowing the student user to enhance the system's adaptivity by improving the accuracy of the underlying learner model. Open Learner Modelling, where the system's model of the user's knowledge is revealed to the user, has been proposed to support student reflection on their learning. Increased accuracy of the learner model can be obtained by the student and system jointly negotiating the learner model. We present the initial investigations into a system to allow people to negotiate the model of their understanding of a topic in natural language. This paper discusses the development and capabilities of both conversational agents (or chatbots) and Intelligent Tutoring Systems, in particular Open Learner Modelling. We describe a Wizard-of-Oz experiment to investigate the feasibility of using a chatbot to support negotiation, and conclude that a fusion of the two fields can lead to developing negotiation techniques for chatbots and the enhancement of the Open Learner Model. This technology, if successful, could have widespread application in schools, universities and other training scenarios.
Alépée, Natalie; Bahinski, Anthony; Daneshian, Mardas; De Wever, Bart; Fritsche, Ellen; Goldberg, Alan; Hansmann, Jan; Hartung, Thomas; Haycock, John; Hogberg, Helena T.; Hoelting, Lisa; Kelm, Jens M.; Kadereit, Suzanne; McVey, Emily; Landsiedel, Robert; Leist, Marcel; Lübberstedt, Marc; Noor, Fozia; Pellevoisin, Christian; Petersohn, Dirk; Pfannenbecker, Uwe; Reisinger, Kerstin; Ramirez, Tzutzuy; Rothen-Rutishauser, Barbara; Schäfer-Korting, Monika; Zeilinger, Katrin; Zurich, Marie-Gabriele
2016-01-01
Summary Integrated approaches using different in vitro methods in combination with bioinformatics can (i) increase the success rate and speed of drug development; (ii) improve the accuracy of toxicological risk assessment; and (iii) increase our understanding of disease. Three-dimensional (3D) cell culture models are important building blocks of this strategy which has emerged during the last years. The majority of these models are organotypic, i.e., they aim to reproduce major functions of an organ or organ system. This implies in many cases that more than one cell type forms the 3D structure, and often matrix elements play an important role. This review summarizes the state of the art concerning commonalities of the different models. For instance, the theory of mass transport/metabolite exchange in 3D systems and the special analytical requirements for test endpoints in organotypic cultures are discussed in detail. In the next part, 3D model systems for selected organs – liver, lung, skin, brain – are presented and characterized in dedicated chapters. Also, 3D approaches to the modeling of tumors are presented and discussed. All chapters give a historical background, illustrate the large variety of approaches, and highlight up- and downsides as well as specific requirements. Moreover, they refer to the application in disease modeling, drug discovery and safety assessment. Finally, consensus recommendations indicate a roadmap for the successful implementation of 3D models in routine screening. It is expected that the use of such models will accelerate progress by reducing error rates and wrong predictions from compound testing. PMID:25027500
ERIC Educational Resources Information Center
Lin, Wen-Shan; Wang, Chun-Hsien
2012-01-01
The objective of this study is to propose a research framework that investigates the relation between perceived fit and system factors that can motivate learners in continuing utilizing an e-learning system in blended learning instruction. As learners have the face-to-face learning opportunity in interacting with lecturers, the study aims at…
ERIC Educational Resources Information Center
Nworji, Alexander O.
2013-01-01
Most organizations spend millions of dollars due to the impact of improperly implemented database application systems as evidenced by poor data quality problems. The purpose of this quantitative study was to use, and extend, the technology acceptance model (TAM) to assess the impact of information quality and technical quality factors on database…
Extended TAM Model: Impacts of Convenience on Acceptance and Use of Moodle
ERIC Educational Resources Information Center
Hsu, Hsiao-hui; Chang, Yu-ying
2013-01-01
The increasing online access to courses, programs, and information has shifted the control and responsibility of learning process from instructors to learners. Learners' perceptions of and attitudes toward e-learning constitute a critical factor to the success of such system. The purpose of this study is to take TAM (technology acceptance model)…
The Massachusetts Community College Performance-Based Funding Formula: A New Model for New England?
ERIC Educational Resources Information Center
Salomon-Fernandez, Yves
2014-01-01
The Massachusetts community college system is entering a second year with funding for each of its 15 schools determined using a new performance-based formula. Under the new model, 50% of each college's allocation is based on performance on metrics related to enrollment and student success, with added incentives for "at-risk" students…
ERIC Educational Resources Information Center
Zhang, Min; Liu, Yupei; Yan, Weiwei; Zhang, Yan
2017-01-01
Users' continuance intention plays a significant role in the process of information system (IS) service, especially virtual learning community (VLC) services. Following the IS success model and IS post-acceptance model, this study explores the determinants of users' intention to continue using VLCs' service from the perspective of quality,…
Principles of Classroom Management: A Professional Decision-Making Model, 7th Edition
ERIC Educational Resources Information Center
Levin, James; Nolan, James F.
2014-01-01
This text takes a decision-making model approach to classroom management. It provides teachers with a very practical system to influence students to choose to behave productively and to strive for academic success. This widely used text presents an array of decision-making options that guide teachers in developing positive, pro-social classroom…
Improving Emergency Management by Modeling Ant Colonies
2015-03-01
LEFT BLANK vii TABLE OF CONTENTS I. THE INCIDENT COMMAND SYSTEM AND AUTONOMOUS ACTORS ......1 A. PROBLEM STATEMENT...managerial level tasking.12 The Oklahoma City bombing has generally been viewed as a success for the ICS model; however, there were numerous occurrences...developed. The youngest generation of ant 25 Bert Holldobler and Edward O. Wilson, The Ants
ERIC Educational Resources Information Center
Kitchen, Julian; Hodson, John
2013-01-01
Aboriginal education in Canada needs to shift away from the assimilative model to a model of culturally responsive pedagogy. Teacher education programs that serve Aboriginal teachers have an important role to play in developing an education system that both meets mainstream and Indigenous criteria for success. This paper examines the experiences…
Utilizing the Active and Collaborative Learning Model in the Introductory Physics Course
ERIC Educational Resources Information Center
Nam, Nguyen Hoai
2014-01-01
Model of active and collaborative learning (ACLM) applied in training specific subject makes clear advantage due to the goals of knowledge, skills that students got to develop successful future job. The author exploits the learning management system (LMS) of Hanoi National University of Education (HNUE) to establish a learning environment in the…
Archer, Norm; Cocosila, Mihail
2011-08-12
There is a major campaign involving large expenditures of public money to increase the adoption rate of electronic health record (EHR) systems in Canada. To maximize the chances of success in this effort, physician views on EHRs must be addressed, since user perceptions are key to successful implementation of technology innovations. We propose a theoretical model comprising behavioral factors either favoring or against EHR adoption and use in Canadian medical practices, from the physicians' point of view. EHR perceptions of physicians already using EHR systems are compared with those not using one, through the lens of this model. We conducted an online cross-sectional survey in both English and French among medical practitioners across Canada. Data were collected both from physicians using EHRs and those not using EHRs, and analyzed with structural equation modeling (SEM) techniques. We collected 119 responses from EHR users and 100 from nonusers, resulting in 2 valid samples of 102 and 83 participants, respectively. The theoretical adoption model explained 55.8% of the variance in behavioral intention to continue using EHRs for physicians already using them, and 66.8% of the variance in nonuser intention to adopt such systems. Perception of ease of use was found to be the strongest motivator for EHR users (total effect .525), while perceptions of usefulness and of ease of use were the key determinants for nonusers (total effect .538 and .519, respectively) to adopt the system. Users see perceived overall risk associated with EHR adoption as a major obstacle (total effect -.371), while nonusers perceive risk only as a weak indirect demotivator. Of the 13 paths of the SEM model, 5 showed significant differences between the 2 samples (at the .05 level): general doubts about using the system (P = .02), the necessity for the system to be relevant for their job (P < .001), and the necessity for the system to be useful (P = .049) are more important for EHR nonusers than for users, while perceptions of overall obstacles to adoption (P = .03) and system ease of use (P = .042) count more for EHR users than for nonusers. Relatively few differences in perceptions about EHR system adoption and use exist between physicians already using such systems and those not yet using the systems. To maximize the chances of success for new EHR implementations from a behavioral point of view, general doubts about the rationale for such systems must be mitigated through improving design, stressing how EHRs are relevant to physician jobs, and providing substantiating evidence that EHRs are easier to use and more effective than nonusers might expect.
Analysis hierarchical model for discrete event systems
NASA Astrophysics Data System (ADS)
Ciortea, E. M.
2015-11-01
The This paper presents the hierarchical model based on discrete event network for robotic systems. Based on the hierarchical approach, Petri network is analysed as a network of the highest conceptual level and the lowest level of local control. For modelling and control of complex robotic systems using extended Petri nets. Such a system is structured, controlled and analysed in this paper by using Visual Object Net ++ package that is relatively simple and easy to use, and the results are shown as representations easy to interpret. The hierarchical structure of the robotic system is implemented on computers analysed using specialized programs. Implementation of hierarchical model discrete event systems, as a real-time operating system on a computer network connected via a serial bus is possible, where each computer is dedicated to local and Petri model of a subsystem global robotic system. Since Petri models are simplified to apply general computers, analysis, modelling, complex manufacturing systems control can be achieved using Petri nets. Discrete event systems is a pragmatic tool for modelling industrial systems. For system modelling using Petri nets because we have our system where discrete event. To highlight the auxiliary time Petri model using transport stream divided into hierarchical levels and sections are analysed successively. Proposed robotic system simulation using timed Petri, offers the opportunity to view the robotic time. Application of goods or robotic and transmission times obtained by measuring spot is obtained graphics showing the average time for transport activity, using the parameters sets of finished products. individually.
Bilsland, Alan E.; Stevenson, Katrina; Liu, Yu; Hoare, Stacey; Cairney, Claire J.; Roffey, Jon; Keith, W. Nicol
2014-01-01
Cancer cells depend on transcription of telomerase reverse transcriptase (TERT). Many transcription factors affect TERT, though regulation occurs in context of a broader network. Network effects on telomerase regulation have not been investigated, though deeper understanding of TERT transcription requires a systems view. However, control over individual interactions in complex networks is not easily achievable. Mathematical modelling provides an attractive approach for analysis of complex systems and some models may prove useful in systems pharmacology approaches to drug discovery. In this report, we used transfection screening to test interactions among 14 TERT regulatory transcription factors and their respective promoters in ovarian cancer cells. The results were used to generate a network model of TERT transcription and to implement a dynamic Boolean model whose steady states were analysed. Modelled effects of signal transduction inhibitors successfully predicted TERT repression by Src-family inhibitor SU6656 and lack of repression by ERK inhibitor FR180204, results confirmed by RT-QPCR analysis of endogenous TERT expression in treated cells. Modelled effects of GSK3 inhibitor 6-bromoindirubin-3′-oxime (BIO) predicted unstable TERT repression dependent on noise and expression of JUN, corresponding with observations from a previous study. MYC expression is critical in TERT activation in the model, consistent with its well known function in endogenous TERT regulation. Loss of MYC caused complete TERT suppression in our model, substantially rescued only by co-suppression of AR. Interestingly expression was easily rescued under modelled Ets-factor gain of function, as occurs in TERT promoter mutation. RNAi targeting AR, JUN, MXD1, SP3, or TP53, showed that AR suppression does rescue endogenous TERT expression following MYC knockdown in these cells and SP3 or TP53 siRNA also cause partial recovery. The model therefore successfully predicted several aspects of TERT regulation including previously unknown mechanisms. An extrapolation suggests that a dominant stimulatory system may programme TERT for transcriptional stability. PMID:24550717
NSTAR Ion Thruster and Breadboard Power Processor Functional Integration Test Results
NASA Technical Reports Server (NTRS)
Hamley, John A.; Pinero, Luis R.; Rawlin, Vincent K.; Miller, John R.; Myers, Roger M.; Bowers, Glen E.
1996-01-01
A 2.3 kW Breadboard Power Processing Unit (BBPPU) was developed as part of the NASA Solar Electric Propulsion Technology Application Readiness (NSTAR) Program. The NSTAR program will deliver an electric propulsion system based on a 30 cm xenon ion thruster to the New Millennium (NM) program for use as the primary propulsion system for the initial NM flight. The final development test for the BBPPU, the Functional Integration Test, was carried out to demonstrate all aspects of BBPPU operation with an Engineering Model Thruster. Test objectives included: (1) demonstration and validation of automated thruster start procedures, (2) demonstration of stable closed loop control of the thruster beam current, (3) successful response and recovery to thruster faults, and (4) successful safing of the system during simulated spacecraft faults. These objectives were met over the specified 80-120 VDC input voltage range and 0.5-2.3 output power capability of the BBPPU. Two minor anomalies were noted in discharge and neutralizer keeper current. These anomalies did not affect the stability of the system and were successfully corrected.
The Earth System (ES-DOC) Project
NASA Astrophysics Data System (ADS)
Greenslade, Mark; Murphy, Sylvia; Treshansky, Allyn; DeLuca, Cecilia; Guilyardi, Eric; Denvil, Sebastien
2014-05-01
ESSI1.3 New Paradigms, Modelling, and International Collaboration Strategies for Earth System Sciences Earth System Documentation (ES-DOC) is an international project supplying tools & services in support of earth system documentation creation, analysis and dissemination. It is nurturing a sustainable standards based documentation eco-system that aims to become an integral part of the next generation of exa-scale dataset archives. ES-DOC leverages open source software and places end-user narratives at the heart of all it does. ES-DOC has initially focused upon nurturing the Earth System Model (ESM) documentation eco-system. Within this context ES-DOC leverages emerging documentation standards and supports the following projects: Coupled Model Inter-comparison Project Phase 5 (CMIP5); Dynamical Core Model Inter-comparison Project (DCMIP); National Climate Predictions and Projections Platforms Quantitative Evaluation of Downscaling Workshop. This presentation will introduce the project to a wider audience and demonstrate the range of tools and services currently available for use. It will also demonstrate how international collaborative efforts are essential to the success of ES-DOC.
Consumer-directed health care: implications for health care organizations and managers.
Guo, Kristina L
2010-01-01
This article uses a pyramid model to illustrate the key components of consumer-directed health care. Consumer-directed health care is considered the essential strategy needed to lower health care costs and is valuable for making significant strides in health care reform. Consumer-directed health care presents new challenges and opportunities for all health care stakeholders and their managers. The viability of the health system depends on the success of managers to respond rapidly and with precision to changes in the system; thus, new and modified roles of managers are necessary to successfully sustain consumerism efforts to control costs while maintaining access and quality.
Systemic Analysis Approaches for Air Transportation
NASA Technical Reports Server (NTRS)
Conway, Sheila
2005-01-01
Air transportation system designers have had only limited success using traditional operations research and parametric modeling approaches in their analyses of innovations. They need a systemic methodology for modeling of safety-critical infrastructure that is comprehensive, objective, and sufficiently concrete, yet simple enough to be used with reasonable investment. The methodology must also be amenable to quantitative analysis so issues of system safety and stability can be rigorously addressed. However, air transportation has proven itself an extensive, complex system whose behavior is difficult to describe, no less predict. There is a wide range of system analysis techniques available, but some are more appropriate for certain applications than others. Specifically in the area of complex system analysis, the literature suggests that both agent-based models and network analysis techniques may be useful. This paper discusses the theoretical basis for each approach in these applications, and explores their historic and potential further use for air transportation analysis.
The Importance of Information Requirements in Designing Acquisition to Information Systems
NASA Technical Reports Server (NTRS)
Davis, Bruce A.; Hill, Chuck; Maughan, Paul M.
1998-01-01
The partnership model used by NASA's Commercial Remote Sensing Program has been successful in better defining remote sensing functional requirements and translation to technical specifications to address environmental needs of the 21st century.
Benchmarking successional progress in a quantitative food web.
Boit, Alice; Gaedke, Ursula
2014-01-01
Central to ecology and ecosystem management, succession theory aims to mechanistically explain and predict the assembly and development of ecological communities. Yet processes at lower hierarchical levels, e.g. at the species and functional group level, are rarely mechanistically linked to the under-investigated system-level processes which drive changes in ecosystem properties and functioning and are comparable across ecosystems. As a model system for secondary succession, seasonal plankton succession during the growing season is readily observable and largely driven autogenically. We used a long-term dataset from large, deep Lake Constance comprising biomasses, auto- and heterotrophic production, food quality, functional diversity, and mass-balanced food webs of the energy and nutrient flows between functional guilds of plankton and partly fish. Extracting population- and system-level indices from this dataset, we tested current hypotheses about the directionality of successional progress which are rooted in ecosystem theory, the metabolic theory of ecology, quantitative food web theory, thermodynamics, and information theory. Our results indicate that successional progress in Lake Constance is quantifiable, passing through predictable stages. Mean body mass, functional diversity, predator-prey weight ratios, trophic positions, system residence times of carbon and nutrients, and the complexity of the energy flow patterns increased during succession. In contrast, both the mass-specific metabolic activity and the system export decreased, while the succession rate exhibited a bimodal pattern. The weighted connectance introduced here represents a suitable index for assessing the evenness and interconnectedness of energy flows during succession. Diverging from earlier predictions, ascendency and eco-exergy did not increase during succession. Linking aspects of functional diversity to metabolic theory and food web complexity, we reconcile previously disjoint bodies of ecological theory to form a complete picture of successional progress within a pelagic food web. This comprehensive synthesis may be used as a benchmark for quantifying successional progress in other ecosystems.
Benchmarking Successional Progress in a Quantitative Food Web
Boit, Alice; Gaedke, Ursula
2014-01-01
Central to ecology and ecosystem management, succession theory aims to mechanistically explain and predict the assembly and development of ecological communities. Yet processes at lower hierarchical levels, e.g. at the species and functional group level, are rarely mechanistically linked to the under-investigated system-level processes which drive changes in ecosystem properties and functioning and are comparable across ecosystems. As a model system for secondary succession, seasonal plankton succession during the growing season is readily observable and largely driven autogenically. We used a long-term dataset from large, deep Lake Constance comprising biomasses, auto- and heterotrophic production, food quality, functional diversity, and mass-balanced food webs of the energy and nutrient flows between functional guilds of plankton and partly fish. Extracting population- and system-level indices from this dataset, we tested current hypotheses about the directionality of successional progress which are rooted in ecosystem theory, the metabolic theory of ecology, quantitative food web theory, thermodynamics, and information theory. Our results indicate that successional progress in Lake Constance is quantifiable, passing through predictable stages. Mean body mass, functional diversity, predator-prey weight ratios, trophic positions, system residence times of carbon and nutrients, and the complexity of the energy flow patterns increased during succession. In contrast, both the mass-specific metabolic activity and the system export decreased, while the succession rate exhibited a bimodal pattern. The weighted connectance introduced here represents a suitable index for assessing the evenness and interconnectedness of energy flows during succession. Diverging from earlier predictions, ascendency and eco-exergy did not increase during succession. Linking aspects of functional diversity to metabolic theory and food web complexity, we reconcile previously disjoint bodies of ecological theory to form a complete picture of successional progress within a pelagic food web. This comprehensive synthesis may be used as a benchmark for quantifying successional progress in other ecosystems. PMID:24587353
Robot-assisted antegrade in-situ fenestrated stent grafting.
Riga, Celia V; Bicknell, Colin D; Wallace, Daniel; Hamady, Mohamad; Cheshire, Nicholas
2009-05-01
To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.
Jukkala, Angela; Greenwood, Rebecca; Motes, Terry; Block, Velinda
2013-01-01
The new Clinical Nurse Leader (CNL) nursing role was developed to meet the complex health care needs of patients, families, and health care systems. This article describes the process used by nurse leaders at the University of Alabama at Birmingham School of Nursing and Hospital to develop Model C CNL practicum courses, recruit and prepare clinical preceptors, prepare clinical microsystems for CNL students, and develop additional practice partnerships throughout the region. MANAGEMENT AND OUTCOME: Critical to the success of the CNL role is a dynamic partnership between academic and practice leaders.The partnership allows faculty to develop curricula that are relevant and responsive to the rapidly changing health care system. Clinical leaders become more aware of trends and issues in nursing education. Continued growth and success of the CNL role is largely dependent on the ability of faculty and practice partners to collaborate on innovative educational programs and models of care delivery.
A Transparent Translation from Legacy System Model into Common Information Model: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ding, Fei; Simpson, Jeffrey; Zhang, Yingchen
Advance in smart grid is forcing utilities towards better monitoring, control and analysis of distribution systems, and requires extensive cyber-based intelligent systems and applications to realize various functionalities. The ability of systems, or components within systems, to interact and exchange services or information with each other is the key to the success of smart grid technologies, and it requires efficient information exchanging and data sharing infrastructure. The Common Information Model (CIM) is a standard that allows different applications to exchange information about an electrical system, and it has become a widely accepted solution for information exchange among different platforms andmore » applications. However, most existing legacy systems are not developed using CIM, but using their own languages. Integrating such legacy systems is a challenge for utilities, and the appropriate utilization of the integrated legacy systems is even more intricate. Thus, this paper has developed an approach and open-source tool in order to translate legacy system models into CIM format. The developed tool is tested for a commercial distribution management system and simulation results have proved its effectiveness.« less
Rare event computation in deterministic chaotic systems using genealogical particle analysis
NASA Astrophysics Data System (ADS)
Wouters, J.; Bouchet, F.
2016-09-01
In this paper we address the use of rare event computation techniques to estimate small over-threshold probabilities of observables in deterministic dynamical systems. We demonstrate that genealogical particle analysis algorithms can be successfully applied to a toy model of atmospheric dynamics, the Lorenz ’96 model. We furthermore use the Ornstein-Uhlenbeck system to illustrate a number of implementation issues. We also show how a time-dependent objective function based on the fluctuation path to a high threshold can greatly improve the performance of the estimator compared to a fixed-in-time objective function.
Probabilistic Analysis Techniques Applied to Complex Spacecraft Power System Modeling
NASA Technical Reports Server (NTRS)
Hojnicki, Jeffrey S.; Rusick, Jeffrey J.
2005-01-01
Electric power system performance predictions are critical to spacecraft, such as the International Space Station (ISS), to ensure that sufficient power is available to support all the spacecraft s power needs. In the case of the ISS power system, analyses to date have been deterministic, meaning that each analysis produces a single-valued result for power capability because of the complexity and large size of the model. As a result, the deterministic ISS analyses did not account for the sensitivity of the power capability to uncertainties in model input variables. Over the last 10 years, the NASA Glenn Research Center has developed advanced, computationally fast, probabilistic analysis techniques and successfully applied them to large (thousands of nodes) complex structural analysis models. These same techniques were recently applied to large, complex ISS power system models. This new application enables probabilistic power analyses that account for input uncertainties and produce results that include variations caused by these uncertainties. Specifically, N&R Engineering, under contract to NASA, integrated these advanced probabilistic techniques with Glenn s internationally recognized ISS power system model, System Power Analysis for Capability Evaluation (SPACE).
Poncelet, Ann Noelle; Mazotti, Lindsay A; Blumberg, Bruce; Wamsley, Maria A; Grennan, Tim; Shore, William B
2014-01-01
The longitudinal integrated clerkship is a model of clinical education driven by tenets of social cognitive theory, situated learning, and workplace learning theories, and built on a foundation of continuity between students, patients, clinicians, and a system of care. Principles and goals of this type of clerkship are aligned with primary care principles, including patient-centered care and systems-based practice. Academic medical centers can partner with community health systems around a longitudinal integrated clerkship to provide mutual benefits for both organizations, creating a sustainable model of clinical training that addresses medical education and community health needs. A successful one-year longitudinal integrated clerkship was created in partnership between an academic medical center and an integrated community health system. Compared with traditional clerkship students, students in this clerkship had better scores on Clinical Performance Examinations, internal medicine examinations, and high perceptions of direct observation of clinical skills. Advantages for the academic medical center include mitigating the resources required to run a longitudinal integrated clerkship while providing primary care training and addressing core competencies such as systems-based practice, practice-based learning, and interprofessional care. Advantages for the community health system include faculty development, academic appointments, professional satisfaction, and recruitment. Success factors include continued support and investment from both organizations’ leadership, high-quality faculty development, incentives for community-based physician educators, and emphasis on the mutually beneficial relationship for both organizations. Development of a longitudinal integrated clerkship in a community health system can serve as a model for developing and expanding these clerkship options for academic medical centers. PMID:24867551
Poncelet, Ann Noelle; Mazotti, Lindsay A; Blumberg, Bruce; Wamsley, Maria A; Grennan, Tim; Shore, William B
2014-01-01
The longitudinal integrated clerkship is a model of clinical education driven by tenets of social cognitive theory, situated learning, and workplace learning theories, and built on a foundation of continuity between students, patients, clinicians, and a system of care. Principles and goals of this type of clerkship are aligned with primary care principles, including patient-centered care and systems-based practice. Academic medical centers can partner with community health systems around a longitudinal integrated clerkship to provide mutual benefits for both organizations, creating a sustainable model of clinical training that addresses medical education and community health needs. A successful one-year longitudinal integrated clerkship was created in partnership between an academic medical center and an integrated community health system. Compared with traditional clerkship students, students in this clerkship had better scores on Clinical Performance Examinations, internal medicine examinations, and high perceptions of direct observation of clinical skills.Advantages for the academic medical center include mitigating the resources required to run a longitudinal integrated clerkship while providing primary care training and addressing core competencies such as systems-based practice, practice-based learning, and interprofessional care. Advantages for the community health system include faculty development, academic appointments, professional satisfaction, and recruitment.Success factors include continued support and investment from both organizations' leadership, high-quality faculty development, incentives for community-based physician educators, and emphasis on the mutually beneficial relationship for both organizations. Development of a longitudinal integrated clerkship in a community health system can serve as a model for developing and expanding these clerkship options for academic medical centers.
A simple, semi-prescriptive self-assessment model for TQM.
Warwood, Stephen; Antony, Jiju
2003-01-01
This article presents a simple, semi-prescriptive self-assessment model for use in industry as part of a continuous improvement program such as Total Quality Management (TQM). The process by which the model was constructed started with a review of the available literature in order to research TQM success factors. Next, postal surveys were conducted by sending questionnaires to the winning organisations of the Baldrige and European Quality Awards and to a preselected group of enterprising UK organisations. From the analysis of this data, the self-assessment model was constructed to help organisations in their quest for excellence. This work confirmed the findings from the literature, that there are key factors that contribute to the successful implementation of TQM and these have different levels of importance. These key factors, in order of importance, are: effective leadership, the impact of other quality-related programs, measurement systems, organisational culture, education and training, the use of teams, efficient communications, active empowerment of the workforce, and a systems infrastructure to support the business and customer-focused processes. This analysis, in turn, enabled the design of a self-assessment model that can be applied within any business setting. Further work should include the testing and review of this model to ascertain its suitability and effectiveness within industry today.
Ablator Response Model Development: From Flight Data Back to Fundamental Experiments
NASA Technical Reports Server (NTRS)
Mansour, Nagi N.; Lachaud, Jean R.
2013-01-01
The successful Mars atmospheric entry by the Mars Science Laboratory (MSL-Curiosity) combined with the success of the Earth atmospheric entry by the Stardust capsule have established PICA as a major Thermal Protection Systems (TPS) material. We expect that this class of materials will be on the short list selected by NASA for any atmospheric entry missions and that it will be the lead of that list of materials in any planning, feasibility studies or flight readiness studies. In addition to NASAs successes, the Dragon capsule, the successful commercial space vehicle built by SpaceX, uses PICA-X, while the European Space Agency is considering ASTERM for its exploration missions that involve atmospheric entries, both of these materials are of the same family as PICA. In the talk, a high-fidelity model will be detailed and discussed. The model tracks the chemical composition of the gases produced during pyrolysis. As in the conventional models, it uses equilibrium chemistry to determine the recession rate at high temperatures but switches to in-volume finite-rate ablation for lower temperatures. It also tracks the time evolution of the porosity of the material. Progress in implementing this high-fidelity model in a code will be presented. In addition, a set of basic experimental data being supported for model validation will be summarized. The validation process for the model development will be discussed. Preliminary results will be presented for a case where detailed pyrolysis product chemistry is computed. Finally, a wish list for a set of validation experiments will be outlined and discussed.
Using a MOOC Format for a Precalculus Course
ERIC Educational Resources Information Center
Townsley, Lisa
2016-01-01
We describe recent attempts by the University System of Georgia to develop and pilot a system-wide online Precalculus course for credit. The course was based on full online delivery, using an emporium model for learning. We experienced moderate success with the course, with a completion rate of 61-76% compared with the 4-7% for Massive Open Online…
DOT National Transportation Integrated Search
1998-01-01
The Arizona Department of Transportation's (ADOT) Trailmaster Freeway Management System is integral to AZTech. Trailmaster provides state-of-the-art traffic management through a variety of electronic means, such as collecting and distributing traffic...
ERIC Educational Resources Information Center
Ramirez, Carlo; And Others
A three-month Federally sponsored program for Spanish-speaking entrepreneurs in the San Francisco area was conducted in 1975 by Amex Systems to examine successful or exemplary education and training systems for minority entrepreneurs, develop a manual for organizing new training programs, and promote the establishment of additional programs. The…
ERIC Educational Resources Information Center
Fan, Chung-Hau; Denner, Peter R.; Bocanegra, Joel O.; Ding, Yi
2016-01-01
After the change in IDEIA, different models of response to intervention (RtI) have been practiced widely in American school systems. School psychologists are in an important position to facilitate RtI practice and provide professional development in order to help their school systems successfully undergo this transformation. However, there is a…
DOT National Transportation Integrated Search
1998-01-01
As an international showcase for intelligent transportation, AZTech has a mission of creating a regional intermodal transportation system through public and private partnerships. In working toward this lofty goal, AZTech's most valuable commodity has...
Evaluating the Wider Outcomes of Schools: Complex Systems Modelling for Leadership Decisioning
ERIC Educational Resources Information Center
Crick, Ruth Deakin; Barr, Steven; Green, Howard; Pedder, David
2017-01-01
A continuing challenge for the education system is how to evaluate the wider outcomes of schools. Wider measures of success--such as citizenship or lifelong learning--influence each other and emerge over time from complex interactions between students, teachers and leaders, and the wider community. Unless methods are found to evaluate these…
Miss-distance indicator for tank main guns
NASA Astrophysics Data System (ADS)
Bornstein, Jonathan A.; Hillis, David B.
1996-06-01
Tank main gun systems must possess extremely high levels of accuracy to perform successfully in battle. Under some circumstances, the first round fired in an engagement may miss the intended target, and it becomes necessary to rapidly correct fire. A breadboard automatic miss-distance indicator system was previously developed to assist in this process. The system, which would be mounted on a 'wingman' tank, consists of a charged-coupled device (CCD) camera and computer-based image-processing system, coupled with a separate infrared sensor to detect muzzle flash. For the system to be successfully employed with current generation tanks, it must be reliable, be relatively low cost, and respond rapidly maintaining current firing rates. Recently, the original indicator system was developed further in an effort to assist in achieving these goals. Efforts have focused primarily upon enhanced image-processing algorithms, both to improve system reliability and to reduce processing requirements. Intelligent application of newly refined trajectory models has permitted examination of reduced areas of interest and enhanced rejection of false alarms, significantly improving system performance.
Afanvi, Kossivi Agbelenko
2015-01-01
The ultimate goal of every tuberculosis (TB) treatment program is a high treatment success rate. Treatment success is extremely important because, when the rate is high, it significantly contributes to declining numbers of new cases by reducing the number and period of infectious cases, TB morbidity and mortality, and prevents the emergence of resistant strains. Our aim was to decrease TB mortality by increasing pulmonary TB patients’ treatment success rate to at least 85 % in Lacs Health District by end of July 2014. A systems and dialogic analysis of the public health system related to TB patients’ treatment revealed that it was not performing well; we found weak coverage and quality of TB services, a poorly-functioning TB health information system, poor-performing health workforce, poor availability of HIV tests and antiretroviral for TB patients, and low degree of patients’ participation in their care. We redesigned the system to correct those weaknesses. The effectiveness of these changes was monitored using plan, do, study, act (PDSA) cycles. We increased TB patient success rate from 80% to 95% between February 2012 and July 2014.The mortality rate dropped from 13% to 3% and the failure to follow-up rate dropped from 3% to 2%. In conclusion, district health systems performance depends on factors such as the closeness of services to population; skilled workforce; the ability to collect and analyze data and use information for action; population empowerment, and good management and improvement capabilities of management team especially the public health director. High TB patients’ success rate depends also on the availability of antiretroviral drugs. It is highly important that every district health management team member develops improvement capabilities. PMID:26734412
Demonstrating artificial intelligence for space systems - Integration and project management issues
NASA Technical Reports Server (NTRS)
Hack, Edmund C.; Difilippo, Denise M.
1990-01-01
As part of its Systems Autonomy Demonstration Project (SADP), NASA has recently demonstrated the Thermal Expert System (TEXSYS). Advanced real-time expert system and human interface technology was successfully developed and integrated with conventional controllers of prototype space hardware to provide intelligent fault detection, isolation, and recovery capability. Many specialized skills were required, and responsibility for the various phases of the project therefore spanned multiple NASA centers, internal departments and contractor organizations. The test environment required communication among many types of hardware and software as well as between many people. The integration, testing, and configuration management tools and methodologies which were applied to the TEXSYS project to assure its safe and successful completion are detailed. The project demonstrated that artificial intelligence technology, including model-based reasoning, is capable of the monitoring and control of a large, complex system in real time.
Flight Testing an Iced Business Jet for Flight Simulation Model Validation
NASA Technical Reports Server (NTRS)
Ratvasky, Thomas P.; Barnhart, Billy P.; Lee, Sam; Cooper, Jon
2007-01-01
A flight test of a business jet aircraft with various ice accretions was performed to obtain data to validate flight simulation models developed through wind tunnel tests. Three types of ice accretions were tested: pre-activation roughness, runback shapes that form downstream of the thermal wing ice protection system, and a wing ice protection system failure shape. The high fidelity flight simulation models of this business jet aircraft were validated using a software tool called "Overdrive." Through comparisons of flight-extracted aerodynamic forces and moments to simulation-predicted forces and moments, the simulation models were successfully validated. Only minor adjustments in the simulation database were required to obtain adequate match, signifying the process used to develop the simulation models was successful. The simulation models were implemented in the NASA Ice Contamination Effects Flight Training Device (ICEFTD) to enable company pilots to evaluate flight characteristics of the simulation models. By and large, the pilots confirmed good similarities in the flight characteristics when compared to the real airplane. However, pilots noted pitch up tendencies at stall with the flaps extended that were not representative of the airplane and identified some differences in pilot forces. The elevator hinge moment model and implementation of the control forces on the ICEFTD were identified as a driver in the pitch ups and control force issues, and will be an area for future work.
Combining fuzzy mathematics with fuzzy logic to solve business management problems
NASA Astrophysics Data System (ADS)
Vrba, Joseph A.
1993-12-01
Fuzzy logic technology has been applied to control problems with great success. Because of this, many observers fell that fuzzy logic is applicable only in the control arena. However, business management problems almost never deal with crisp values. Fuzzy systems technology--a combination of fuzzy logic, fuzzy mathematics and a graphical user interface--is a natural fit for developing software to assist in typical business activities such as planning, modeling and estimating. This presentation discusses how fuzzy logic systems can be extended through the application of fuzzy mathematics and the use of a graphical user interface to make the information contained in fuzzy numbers accessible to business managers. As demonstrated through examples from actual deployed systems, this fuzzy systems technology has been employed successfully to provide solutions to the complex real-world problems found in the business environment.
Mechanisms of herbaceous vegetation restoration successions
NASA Astrophysics Data System (ADS)
Pankratova, Lubov
2017-04-01
The vegetation dynamics study is an important sector of research in phytocenology. The changing vegetation mechanisms' studying with the purpose of forecasting and management processes is an urgent theoretical and practical task. We consider succession as successive series of composition changes and phytocenoses structure caused by internal reasons and external ones. In this case, we are dealing with natural, secondary and progressive successions. The rapid sequential change of associations aimed at restoring coenotic environment and not resulting in ecogenesis stage changes is called demattia. Fully restored coenotic environment corresponds to vegetation sublimation. The way to this most stable state goes via a number of derived associations, each of them can be seen as long phytocenotic sustainable phenomenon, but different in time. The ability of living beings to reproduce in one way or another, their spreading, filling the space and confrontation to adverse conditions presents an important preservation mechanism and biodiversity increase, as well as its sustainability. The bio-diversity indicator is very significant for stability maintainment and phytocenosis estimation. Succession mechanisms classification provides three categories of relationships between organisms in the successional series: model relief or stimulation corresponds to the phase of endoecological succession which means that early settlers in their activities change the environment, making it available for the next wave of colonists. The model of tolerance manifests itself in the form of competitive relationships, resulting in selection of more competitive species with a pronounced feature S. According to the inhibition model, all types of community are able to colonize open spaces, they are resistant to competitors invasion, but the later species are able to inhabit and increase their number only after the loss of any of the predecessors. The predecessors change environment settings making it less suitable for later species. The fourth model of neutrality corresponds to the succession, considered as a population process, with the change of species populations of different life cycles and different ecological-phytocenotic types of strategies. Often this model applies only to the formation of the species composition but quantitative ratios between the species are caused by a weakened manifestation of favored, inhibiting or tolerance effects. All the mechanisms together provide the plant communities development from the beginning stages to the end due to system feedbacks (positive and negative). In the first stages of succession the ecosystem is able to resume quickly, indicating a fairly high resilience, which means the movement to a climax is constantly decreasing. The trend is opposite for self-sustainability or stability. In the early stages of succession, its value is low enough - the systems are very sensitive to external influences, responding to them with increased dynamism. The resident resistance is continuously growing with species increasing. As you get closer to menopause, the ecosystem becomes more sensitive to the effects of some catastrophic environmental factors, which means that with ongoing stable growth the factor of ecosystem rigidity going to a climax apparently even begins to decrease.
The Ensemble Space Weather Modeling System (eSWMS): Status, Capabilities and Challenges
NASA Astrophysics Data System (ADS)
Fry, C. D.; Eccles, J. V.; Reich, J. P.
2010-12-01
Marking a milestone in space weather forecasting, the Space Weather Modeling System (SWMS) successfully completed validation testing in advance of operational testing at Air Force Weather Agency’s primary space weather production center. This is the first coupling of stand-alone, physics-based space weather models that are currently in operations at AFWA supporting the warfighter. Significant development effort went into ensuring the component models were portable and scalable while maintaining consistent results across diverse high performance computing platforms. Coupling was accomplished under the Earth System Modeling Framework (ESMF). The coupled space weather models are the Hakamada-Akasofu-Fry version 2 (HAFv2) solar wind model and GAIM1, the ionospheric forecast component of the Global Assimilation of Ionospheric Measurements (GAIM) model. The SWMS was developed by team members from AFWA, Explorations Physics International, Inc. (EXPI) and Space Environment Corporation (SEC). The successful development of the SWMS provides new capabilities beyond enabling extended lead-time, data-driven ionospheric forecasts. These include ingesting diverse data sets at higher resolution, incorporating denser computational grids at finer time steps, and performing probability-based ensemble forecasts. Work of the SWMS development team now focuses on implementing the ensemble-based probability forecast capability by feeding multiple scenarios of 5 days of solar wind forecasts to the GAIM1 model based on the variation of the input fields to the HAFv2 model. The ensemble SWMS (eSWMS) will provide the most-likely space weather scenario with uncertainty estimates for important forecast fields. The eSWMS will allow DoD mission planners to consider the effects of space weather on their systems with more advance warning than is currently possible. The payoff is enhanced, tailored support to the warfighter with improved capabilities, such as point-to-point HF propagation forecasts, single-frequency GPS error corrections, and high cadence, high-resolution Space Situational Awareness (SSA) products. We present the current status of eSWMS, its capabilities, limitations and path of transition to operational use.
1980-05-01
102 17. A Feasibility Study: Application of Lidar Transmission Measurement in the Slant Visual Range Problem - Ronald H. Kohl 108 18. Multiwavelength ...discrete filters gives greater spectral resolution over the whole band. The success of the Model 14-703 System led to the development of a more advanced...REQUIREMENTS Success in a wide range of atmospheric transmission measurement applications has led to the reqi,-st for more advanced capabilities which are listed
Redesign and commissioning of sexual health services in England - a qualitative study.
Walker, I F; Leigh-Hunt, N; Lee, A C K
2016-10-01
Responsibility for the commissioning of sexual and reproductive health (SRH) services transferred from the National Health Service to local authorities in England in 2013. This transfer prompted many local authorities to undertake new procurements of these SRH services. This study was undertaken to capture some of the lessons learnt in order to inform future commissioning and system redesign. A qualitative study was carried out involving semi-structured interviews. Interviews were conducted with 13 local authority sexual health commissioners in Yorkshire and the Humber from 11 interviews. Thematic analysis was used to identify themes from transcripts of the interviews with the 13 participants. Key themes identified were as follows: the challenge and complexity to those new to clinical commissioning; the prerequisites of robust infrastructural inputs to undertake the process, including technical expertise, a dependable project team, with clarity over the timescales and the budget; the requirement for good governance, stakeholder engagement and successful management of relationships with the latter; and the need to focus on the outcomes, aiming for value for money and improved system performance. Several key issues emerged from our study that significantly influenced the outcome of the redesign and commissioning process for sexual health services. An adapted model of the Donabedian evaluation framework was developed to provide a tool to inform future system redesign. Our model helps identify the key determinants for successful redesign in this context which is essential to both mitigate potential risks and maximize the likelihood of successful outcomes. Our model may have wider applications. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Building a generalized distributed system model
NASA Technical Reports Server (NTRS)
Mukkamala, R.
1992-01-01
The key elements in the second year (1991-92) of our project are: (1) implementation of the distributed system prototype; (2) successful passing of the candidacy examination and a PhD proposal acceptance by the funded student; (3) design of storage efficient schemes for replicated distributed systems; and (4) modeling of gracefully degrading reliable computing systems. In the third year of the project (1992-93), we propose to: (1) complete the testing of the prototype; (2) enhance the functionality of the modules by enabling the experimentation with more complex protocols; (3) use the prototype to verify the theoretically predicted performance of locking protocols, etc.; and (4) work on issues related to real-time distributed systems. This should result in efficient protocols for these systems.
Evaluating the Functionality of Conceptual Models
NASA Astrophysics Data System (ADS)
Mehmood, Kashif; Cherfi, Samira Si-Said
Conceptual models serve as the blueprints of information systems and their quality plays decisive role in the success of the end system. It has been witnessed that majority of the IS change-requests results due to deficient functionalities in the information systems. Therefore, a good analysis and design method should ensure that conceptual models are functionally correct and complete, as they are the communicating mediator between the users and the development team. Conceptual model is said to be functionally complete if it represents all the relevant features of the application domain and covers all the specified requirements. Our approach evaluates the functional aspects on multiple levels of granularity in addition to providing the corrective actions or transformation for improvement. This approach has been empirically validated by practitioners through a survey.
Using waveform information in nonlinear data assimilation
NASA Astrophysics Data System (ADS)
Rey, Daniel; Eldridge, Michael; Morone, Uriel; Abarbanel, Henry D. I.; Parlitz, Ulrich; Schumann-Bischoff, Jan
2014-12-01
Information in measurements of a nonlinear dynamical system can be transferred to a quantitative model of the observed system to establish its fixed parameters and unobserved state variables. After this learning period is complete, one may predict the model response to new forces and, when successful, these predictions will match additional observations. This adjustment process encounters problems when the model is nonlinear and chaotic because dynamical instability impedes the transfer of information from the data to the model when the number of measurements at each observation time is insufficient. We discuss the use of information in the waveform of the data, realized through a time delayed collection of measurements, to provide additional stability and accuracy to this search procedure. Several examples are explored, including a few familiar nonlinear dynamical systems and small networks of Colpitts oscillators.
Strategic behavior and governance challenges in self-organized coupled natural-human systems
NASA Astrophysics Data System (ADS)
Muneepeerakul, R.; Anderies, J. M.
2017-12-01
Successful and sustainable coupling of human societies and natural systems requires effective governance, which depends on the existence of proper infrastructure (both hard and soft). In recent decades, much attention has been paid to what has allowed many small-scale self-organized coupled natural-human systems around the world to persist for centuries, thanks to a large part to the work by Elinor Ostrom and colleagues. In this work, we mathematically operationalize a conceptual framework that is developed based on this body of work by way of a stylized model. The model captures the interplay between replicator dynamics within the population, dynamics of natural resources, and threshold characteristics of public infrastructure. The model analysis reveals conditions for long-term sustainability and collapse of the coupled systems as well as other tradeoffs and potential pitfalls in governing these systems.
Application of uniform design to improve dental implant system.
Cheng, Yung-Chang; Lin, Deng-Huei; Jiang, Cho-Pei
2015-01-01
This paper introduces the application of uniform experimental design to improve dental implant systems subjected to dynamic loads. The dynamic micromotion of the Zimmer dental implant system is calculated and illustrated by explicit dynamic finite element analysis. Endogenous and exogenous factors influence the success rate of dental implant systems. Endogenous factors include: bone density, cortical bone thickness and osseointegration. Exogenous factors include: thread pitch, thread depth, diameter of implant neck and body size. A dental implant system with a crest module was selected to simulate micromotion distribution and stress behavior under dynamic loads using conventional and proposed methods. Finally, the design which caused minimum micromotion was chosen as the optimal design model. The micromotion of the improved model is 36.42 μm, with an improvement is 15.34% as compared to the original model.
Assefa, Yibeltal; Van Damme, Wim; Hermann, Katharina
2010-01-01
PURPOSE OF VIEW: To illustrate and critically assess what is currently being published on the human resources for health dimension of antiretroviral therapy (ART) delivery models. The use of human resources for health can have an effect on two crucial aspects of successful ART programmes, namely the scale-up capacity and the long-term retention in care. Task shifting as the delegation of tasks from higher qualified to lower qualified cadres has become a widespread practice in ART delivery models in low-income countries in recent years. It is increasingly shown to effectively reduce the workload for scarce medical doctors without compromising the quality of care. At the same time, it becomes clear that task shifting can only be successful when accompanied by intensive training, supervision and support from existing health system structures. Although a number of recent publications have focussed on task shifting in ART delivery models, there is a lack of accessible information on the link between task shifting and patient outcomes. Current ART delivery models do not focus sufficiently on retention in care as arguably one of the most important issues for the long-term success of ART programmes. There is a need for context-specific re-designing of current ART delivery models in order to increase access to ART and improve long-term retention.
Charge frustration in complex fluids and in electronic systems
NASA Astrophysics Data System (ADS)
Carraro, Carlo
1997-02-01
The idea of charge frustration is applied to describe the properties of such diverse physical systems as oil-water-surfactant mixtures and metal-ammonia solutions. The minimalist charge-frustrated model possesses one energy scale and two length scales. For oil-water-surfactant mixtures, these parameters have been determined starting from the microscopic properties of the physical systems under study. Thus, microscopic properties are successfully related to the observed mesoscopic structure.
Chan, Joshua L; Mazilu, Dumitru; Miller, Justin G; Hunt, Timothy; Horvath, Keith A; Li, Ming
2016-10-01
Real-time magnetic resonance imaging (rtMRI) guidance provides significant advantages during transcatheter aortic valve replacement (TAVR) as it provides superior real-time visualization and accurate device delivery tracking. However, performing a TAVR within an MRI scanner remains difficult due to a constrained procedural environment. To address these concerns, a magnetic resonance (MR)-compatible robotic system to assist in TAVR deployments was developed. This study evaluates the technical design and interface considerations of an MR-compatible robotic-assisted TAVR system with the purpose of demonstrating that such a system can be developed and executed safely and precisely in a preclinical model. An MR-compatible robotic surgical assistant system was built for TAVR deployment. This system integrates a 5-degrees of freedom (DoF) robotic arm with a 3-DoF robotic valve delivery module. A user interface system was designed for procedural planning and real-time intraoperative manipulation of the robot. The robotic device was constructed of plastic materials, pneumatic actuators, and fiber-optical encoders. The mechanical profile and MR compatibility of the robotic system were evaluated. The system-level error based on a phantom model was 1.14 ± 0.33 mm. A self-expanding prosthesis was successfully deployed in eight Yorkshire swine under rtMRI guidance. Post-deployment imaging and necropsy confirmed placement of the stent within 3 mm of the aortic valve annulus. These phantom and in vivo studies demonstrate the feasibility and advantages of robotic-assisted TAVR under rtMRI guidance. This robotic system increases the precision of valve deployments, diminishes environmental constraints, and improves the overall success of TAVR.
NASA Astrophysics Data System (ADS)
Ullrich, Paul A.; Jablonowski, Christiane; Kent, James; Lauritzen, Peter H.; Nair, Ramachandran; Reed, Kevin A.; Zarzycki, Colin M.; Hall, David M.; Dazlich, Don; Heikes, Ross; Konor, Celal; Randall, David; Dubos, Thomas; Meurdesoif, Yann; Chen, Xi; Harris, Lucas; Kühnlein, Christian; Lee, Vivian; Qaddouri, Abdessamad; Girard, Claude; Giorgetta, Marco; Reinert, Daniel; Klemp, Joseph; Park, Sang-Hun; Skamarock, William; Miura, Hiroaki; Ohno, Tomoki; Yoshida, Ryuji; Walko, Robert; Reinecke, Alex; Viner, Kevin
2017-12-01
Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier-Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and their individual successes suggest that no perfect model exists. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 non-hydrostatic dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP) workshop and summer school. This review includes a choice of model grid, variable placement, vertical coordinate, prognostic equations, temporal discretization, and the diffusion, stabilization, filters, and fixers employed by each system.
Efficient Embedded Decoding of Neural Network Language Models in a Machine Translation System.
Zamora-Martinez, Francisco; Castro-Bleda, Maria Jose
2018-02-22
Neural Network Language Models (NNLMs) are a successful approach to Natural Language Processing tasks, such as Machine Translation. We introduce in this work a Statistical Machine Translation (SMT) system which fully integrates NNLMs in the decoding stage, breaking the traditional approach based on [Formula: see text]-best list rescoring. The neural net models (both language models (LMs) and translation models) are fully coupled in the decoding stage, allowing to more strongly influence the translation quality. Computational issues were solved by using a novel idea based on memorization and smoothing of the softmax constants to avoid their computation, which introduces a trade-off between LM quality and computational cost. These ideas were studied in a machine translation task with different combinations of neural networks used both as translation models and as target LMs, comparing phrase-based and [Formula: see text]-gram-based systems, showing that the integrated approach seems more promising for [Formula: see text]-gram-based systems, even with nonfull-quality NNLMs.
NASA Astrophysics Data System (ADS)
Yuan, Dongliang; Xu, Peng; Xu, Tengfei
2017-01-01
An experiment using the Community Climate System Model (CCSM4), a participant of the Coupled Model Intercomparison Project phase-5 (CMIP5), is analyzed to assess the skills of this model in simulating and predicting the climate variabilities associated with the oceanic channel dynamics across the Indo-Pacific Oceans. The results of these analyses suggest that the model is able to reproduce the observed lag correlation between the oceanic anomalies in the southeastern tropical Indian Ocean and those in the cold tongue in the eastern equatorial Pacific Ocean at a time lag of 1 year. This success may be largely attributed to the successful simulation of the interannual variations of the Indonesian Throughflow, which carries the anomalies of the Indian Ocean Dipole (IOD) into the western equatorial Pacific Ocean to produce subsurface temperature anomalies, which in turn propagate to the eastern equatorial Pacific to generate ENSO. This connection is termed the "oceanic channel dynamics" and is shown to be consistent with the observational analyses. However, the model simulates a weaker connection between the IOD and the interannual variability of the Indonesian Throughflow transport than found in the observations. In addition, the model overestimates the westerly wind anomalies in the western-central equatorial Pacific in the year following the IOD, which forces unrealistic upwelling Rossby waves in the western equatorial Pacific and downwelling Kelvin waves in the east. This assessment suggests that the CCSM4 coupled climate system has underestimated the oceanic channel dynamics and overestimated the atmospheric bridge processes.
Is Sustainability Achievable? Exploring the Limits of Sustainability with Model Systems
Successful implementation of sustainability ideas in ecosystem management requires a basic understanding of the often nonlinear and non-intuitive relationships amongst different dimensions of sustainability, particularly the systemwide implications of human actions. This basic un...
Byun, Sookeun; Mills, Juline E
2011-01-01
Current business leaders continue to adopt e-learning technology despite concerns regarding its value. Positing that the effectiveness of e-training depends on how its environment is managed, we argue that a learner-centric approach is necessary in order to achieve workplace training goals. We subsequently develop a theoretical model that is aimed at identifying the key components of learner-centered e-training environments, which serve the function of providing a benchmarked approach for evaluating e-training success. The model was empirically tested using data from an Internet survey of retail industry employees and partial least squares techniques were used for analysis. Based on the findings, this study clarifies what is needed for successful e-training in terms of instructional design, system design, and organizational support.
Disruptive innovation in academic medical centers: balancing accountable and academic care.
Stein, Daniel; Chen, Christopher; Ackerly, D Clay
2015-05-01
Numerous academic medicine leaders have argued that academic referral centers must prepare for the growing importance of accountability-driven payment models by adopting population health initiatives. Although this shift has merit, execution of this strategy will prove significantly more problematic than most observers have appreciated. The authors describe how successful implementation of an accountable care health strategy within a referral academic medical center (AMC) requires navigating a critical tension: The academic referral business model, driven by tertiary-level care, is fundamentally in conflict with population health. Referral AMCs that create successful value-driven population health systems within their organizations will in effect disrupt their own existing tertiary care businesses. The theory of disruptive innovation suggests that balancing the push and pull of academic and accountable care within a single organization is achievable. However, it will require significant shifts in resource allocation and changes in management structure to enable AMCs to make the inherent difficult choices and trade-offs that will ensue. On the basis of the theories of disruptive innovation, the authors present recommendations for how academic health systems can successfully navigate these issues as they transition toward accountability-driven care.
Goldschmidt, Felix; Regoes, Roland R; Johnson, David R
2017-09-01
Successive range expansions occur within all domains of life, where one population expands first (primary expansion) and one or more secondary populations then follow (secondary expansion). In general, genetic drift reduces diversity during range expansion. However, it is not clear whether the same effect applies during successive range expansion, mainly because the secondary population must expand into space occupied by the primary population. Here we used an experimental microbial model system to show that, in contrast to primary range expansion, successive range expansion promotes local population diversity. Because of mechanical constraints imposed by the presence of the primary population, the secondary population forms fractal-like dendritic structures. This divides the advancing secondary population into many small sub-populations and promotes intermixing between the primary and secondary populations. We further developed a mathematical model to simulate the formation of dendritic structures in the secondary population during succession. By introducing mutations in the primary or dendritic secondary populations, we found that mutations are more likely to accumulate in the dendritic secondary populations. Our results thus show that successive range expansion can promote intermixing over the short term and increase genetic diversity over the long term. Our results therefore have potentially important implications for predicting the ecological processes and evolutionary trajectories of microbial communities.
Using expert systems to implement a semantic data model of a large mass storage system
NASA Technical Reports Server (NTRS)
Roelofs, Larry H.; Campbell, William J.
1990-01-01
The successful development of large volume data storage systems will depend not only on the ability of the designers to store data, but on the ability to manage such data once it is in the system. The hypothesis is that mass storage data management can only be implemented successfully based on highly intelligent meta data management services. There now exists a proposed mass store system standard proposed by the IEEE that addresses many of the issues related to the storage of large volumes of data, however, the model does not consider a major technical issue, namely the high level management of stored data. However, if the model were expanded to include the semantics and pragmatics of the data domain using a Semantic Data Model (SDM) concept, the result would be data that is expressive of the Intelligent Information Fusion (IIF) concept and also organized and classified in context to its use and purpose. The results are presented of a demonstration prototype SDM implemented using the expert system development tool NEXPERT OBJECT. In the prototype, a simple instance of a SDM was created to support a hypothetical application for the Earth Observing System, Data Information System (EOSDIS). The massive amounts of data that EOSDIS will manage requires the definition and design of a powerful information management system in order to support even the most basic needs of the project. The application domain is characterized by a semantic like network that represents the data content and the relationships between the data based on user views and the more generalized domain architectural view of the information world. The data in the domain are represented by objects that define classes, types and instances of the data. In addition, data properties are selectively inherited between parent and daughter relationships in the domain. Based on the SDM a simple information system design is developed from the low level data storage media, through record management and meta data management to the user interface.
Modelling and experimental performance analysis of solar-assisted ground source heat pump system
NASA Astrophysics Data System (ADS)
Esen, Hikmet; Esen, Mehmet; Ozsolak, Onur
2017-01-01
In this study, slinky (the slinky-loop configuration is also known as the coiled loop or spiral loop of flexible plastic pipe)type ground heat exchanger (GHE) was established for a solar-assisted ground source heat pump system. System modelling is performed with the data obtained from the experiment. Artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) are used in modelling. The slinky pipes have been laid horizontally and vertically in a ditch. The system coefficient of performance (COPsys) and the heat pump coefficient of performance (COPhp) have been calculated as 2.88 and 3.55, respectively, at horizontal slinky-type GHE, while COPsys and COPhp were calculated as 2.34 and 2.91, respectively, at vertical slinky-type GHE. The obtained results showed that the ANFIS is more successful than that of ANN for forecasting performance of a solar ground source heat pump system.
NASA Technical Reports Server (NTRS)
Scott, Robert C.; Vetter, Travis K.; Penning, Kevin B.; Coulson, David A.; Heeg, Jennifer
2014-01-01
This is part 2 of a two part document. Part 1 is titled: "Aeroservoelastic Testing of Free Flying Wind Tunnel Models Part 1: A Sidewall Supported Semispan Model Tested for Gust Load Alleviation and Flutter Suppression." A team comprised of the Air Force Research Laboratory (AFRL), Boeing, and the NASA Langley Research Center conducted three aeroservoelastic wind tunnel tests in the Transonic Dynamics Tunnel to demonstrate active control technologies relevant to large, flexible vehicles. In the first of these three tests, a full-span, aeroelastically scaled, wind tunnel model of a joined wing SensorCraft vehicle was mounted to a force balance to acquire a basic aerodynamic data set. In the second and third tests, the same wind tunnel model was mated to a new, two degree of freedom, beam mount. This mount allowed the full-span model to translate vertically and pitch. Trimmed flight at10 percent static margin and gust load alleviation were successfully demonstrated. The rigid body degrees of freedom required that the model be flown in the wind tunnel using an active control system. This risky mode of testing necessitated that a model arrestment system be integrated into the new mount. The safe and successful completion of these free-flying tests required the development and integration of custom hardware and software. This paper describes the many systems, software, and procedures that were developed as part of this effort. The balance and free flying wind tunnel tests will be summarized. The design of the trim and gust load alleviation control laws along with the associated results will also be discussed.
Automated, Parametric Geometry Modeling and Grid Generation for Turbomachinery Applications
NASA Technical Reports Server (NTRS)
Harrand, Vincent J.; Uchitel, Vadim G.; Whitmire, John B.
2000-01-01
The objective of this Phase I project is to develop a highly automated software system for rapid geometry modeling and grid generation for turbomachinery applications. The proposed system features a graphical user interface for interactive control, a direct interface to commercial CAD/PDM systems, support for IGES geometry output, and a scripting capability for obtaining a high level of automation and end-user customization of the tool. The developed system is fully parametric and highly automated, and, therefore, significantly reduces the turnaround time for 3D geometry modeling, grid generation and model setup. This facilitates design environments in which a large number of cases need to be generated, such as for parametric analysis and design optimization of turbomachinery equipment. In Phase I we have successfully demonstrated the feasibility of the approach. The system has been tested on a wide variety of turbomachinery geometries, including several impellers and a multi stage rotor-stator combination. In Phase II, we plan to integrate the developed system with turbomachinery design software and with commercial CAD/PDM software.
Emerging Technologies to Create Inducible and Genetically Defined Porcine Cancer Models.
Schook, Lawrence B; Rund, Laurie; Begnini, Karine R; Remião, Mariana H; Seixas, Fabiana K; Collares, Tiago
2016-01-01
There is an emerging need for new animal models that address unmet translational cancer research requirements. Transgenic porcine models provide an exceptional opportunity due to their genetic, anatomic, and physiological similarities with humans. Due to recent advances in the sequencing of domestic animal genomes and the development of new organism cloning technologies, it is now very feasible to utilize pigs as a malleable species, with similar anatomic and physiological features with humans, in which to develop cancer models. In this review, we discuss genetic modification technologies successfully used to produce porcine biomedical models, in particular the Cre-loxP System as well as major advances and perspectives the CRISPR/Cas9 System. Recent advancements in porcine tumor modeling and genome editing will bring porcine models to the forefront of translational cancer research.
Predictability of the Ningaloo Niño/Niña
Doi, Takeshi; Behera, Swadhin K.; Yamagata, Toshio
2013-01-01
The seasonal prediction of the coastal oceanic warm event off West Australia, recently named the Ningaloo Niño, is explored by use of a state-of-the-art ocean-atmosphere coupled general circulation model. The Ningaloo Niño/Niña, which generally matures in austral summer, is found to be predictable two seasons ahead. In particular, the unprecedented extreme warm event in February 2011 was successfully predicted 9 months in advance. The successful prediction of the Ningaloo Niño is mainly due to the high prediction skill of La Niña in the Pacific. However, the model deficiency to underestimate its early evolution and peak amplitude needs to be improved. Since the Ningaloo Niño/Niña has potential impacts on regional societies and industries through extreme events, the present success of its prediction may encourage development of its early warning system. PMID:24100593
The influence of enterprise resource planning (ERP) systems' performance on earnings management
NASA Astrophysics Data System (ADS)
Tsai, Wen-Hsien; Lee, Kuen-Chang; Liu, Jau-Yang; Lin, Sin-Jin; Chou, Yu-Wei
2012-11-01
We analyse whether there is a linkage between performance measures of enterprise resource planning (ERP) systems and earnings management. We find that earnings management decreases with the higher performance of ERP systems. The empirical result is as expected. We further analyse how the dimension of the DeLone and McLean model of information systems success affects earnings management. We find that the relationship between the performance of ERP systems and earnings management depends on System Quality after ERP implementation. The more System Quality improves, the more earnings management is reduced.
NASA Astrophysics Data System (ADS)
Hu, Shanshan; Ma, Jianyong; Shugart, Herman H.; Yan, Xiaodong
2018-03-01
Mountain forests provide the main water resources and lumber for Northwest China. The understanding of the differences in forests growing among individual slope aspects in mountainous regions is of great significance to the wise management and planning of these natural systems. The aim of this study was to investigate the impacts of slope aspect on forest dynamic succession in Northwest China by using the dynamic forest succession model (FAREAST). First, the simulated forest composition and vertical forest zonation produced by the model were compared against recorded data in three sub-regions of the Altai Mountains. The FAREAST model accurately reproduced the vertical zonation, forest composition, growth curves of the dominant species (Larix sibirica), and forest biomass in the Altai Mountains. Transitions along the forest zones of the Altai Mountains averaged about a 400 m difference between the northern and southern sites. Biomass for forests on north-facing slopes were 11.0, 15.3 and 55.9 t C ha-1 higher than for south-facing slopes in the Northeast, Central and Southeast sub-regions, respectively. Second, our analyses showed that the FAREAST model can be used to predict dynamic forest succession in Northwest China under the influence of slope and aspect. In the Altai Mountains, the north-facing slopes supported the best forest growth, followed by the west- and east-facing slopes. South-facing slopes consistently exhibited the lowest growth, biomass storage and forest diversity.
Applications of amorphous track models in radiation biology
NASA Technical Reports Server (NTRS)
Cucinotta, F. A.; Nikjoo, H.; Goodhead, D. T.; Wilson, J. W. (Principal Investigator)
1999-01-01
The average or amorphous track model uses the response of a system to gamma-rays and the radial distribution of dose about an ion's path to describe survival and other cellular endpoints from proton, heavy ion, and neutron irradiation. This model has been used for over 30 years to successfully fit many radiobiology data sets. We review several extensions of this approach that address objections to the original model, and consider applications of interest in radiobiology and space radiation risk assessment. In the light of present views of important cellular targets, the role of target size as manifested through the relative contributions from ion-kill (intra-track) and gamma-kill (inter-track) remains a critical question in understanding the success of the amorphous track model. Several variations of the amorphous model are discussed, including ones that consider the radial distribution of event-sizes rather than average electron dose, damage clusters rather than multiple targets, and a role for repair or damage processing.
An Autonomous Sensor System Architecture for Active Flow and Noise Control Feedback
NASA Technical Reports Server (NTRS)
Humphreys, William M, Jr.; Culliton, William G.
2008-01-01
Multi-channel sensor fusion represents a powerful technique to simply and efficiently extract information from complex phenomena. While the technique has traditionally been used for military target tracking and situational awareness, a study has been successfully completed that demonstrates that sensor fusion can be applied equally well to aerodynamic applications. A prototype autonomous hardware processor was successfully designed and used to detect in real-time the two-dimensional flow reattachment location generated by a simple separated-flow wind tunnel model. The success of this demonstration illustrates the feasibility of using autonomous sensor processing architectures to enhance flow control feedback signal generation.