An integrated methodology to assess the benefits of urban green space.

PubMed

De Ridder, K; Adamec, V; Bañuelos, A; Bruse, M; Bürger, M; Damsgaard, O; Dufek, J; Hirsch, J; Lefebre, F; Pérez-Lacorzana, J M; Thierry, A; Weber, C

2004-12-01

The interrelated issues of urban sprawl, traffic congestion, noise, and air pollution are major socioeconomic problems faced by most European cities. A methodology is currently being developed for evaluating the role of green space and urban form in alleviating the adverse effects of urbanisation, mainly focusing on the environment but also accounting for socioeconomic aspects. The objectives and structure of the methodology are briefly outlined and illustrated with preliminary results obtained from case studies performed on several European cities.

"Sustainability on Earth" Webquests: Do They Qualify as Problem-Based Learning Activities?

ERIC Educational Resources Information Center

Leite, Laurinda; Dourado, Luís; Morgado, Sofia

2015-01-01

Information and communication technologies (ICT), namely the Internet, can play a valuable educational role in several school subjects, including science education. The same applies to problem-based learning (PBL), that is, a student-centered active learning methodology that can prepare students for lifelong learning. WebQuests (WQs) combine PBL…

Advancements in medicine from aerospace research

NASA Technical Reports Server (NTRS)

Wooten, F. T.

1971-01-01

A program designed to find ways of transferring space technology to non-space medicine is discussed. The methodology used to attack the problem and several illustrative examples of the results are given.

Brain Dynamics: Methodological Issues and Applications in Psychiatric and Neurologic Diseases

NASA Astrophysics Data System (ADS)

Pezard, Laurent

The human brain is a complex dynamical system generating the EEG signal. Numerical methods developed to study complex physical dynamics have been used to characterize EEG since the mid-eighties. This endeavor raised several issues related to the specificity of EEG. Firstly, theoretical and methodological studies should address the major differences between the dynamics of the human brain and physical systems. Secondly, this approach of EEG signal should prove to be relevant for dealing with physiological or clinical problems. A set of studies performed in our group is presented here within the context of these two problematic aspects. After the discussion of methodological drawbacks, we review numerical simulations related to the high dimension and spatial extension of brain dynamics. Experimental studies in neurologic and psychiatric disease are then presented. We conclude that if it is now clear that brain dynamics changes in relation with clinical situations, methodological problems remain largely unsolved.

Expert Systems Development Methodology

DTIC Science & Technology

1989-07-28

application. Chapter 9, Design and Prototyping, discusses the problems of designing the user interface and other characteristics of the ES and the prototyping...severely in question as to whether they were computable. In order to work with this problem , Turing created what he called the universal machine. These...about the theory of computers and their relationship to problem solving. It was here at Princeton that he first began to experiment directly with

A Social-Medical Approach to Violence in Colombia

PubMed Central

Franco, Saul

2003-01-01

Violence is the main public health problem in Colombia. Many theoretical and methodological approaches to solving this problem have been attempted from different disciplines. My past work has focused on homicide violence from the perspective of social medicine. In this article I present the main conceptual and methodological aspects and the chief findings of my research over the past 15 years. Findings include a quantitative description of the current situation and the introduction of the category of explanatory contexts as a contribution to the study of Colombian violence. The complexity and severity of this problem demand greater theoretical discussion, more plans for action and a faster transition between the two. Social medicine may make a growing contribution to this field. PMID:14652328

A social-medical approach to violence in Colombia.

PubMed

Franco, Saul

2003-12-01

Violence is the main public health problem in Colombia. Many theoretical and methodological approaches to solving this problem have been attempted from different disciplines. My past work has focused on homicide violence from the perspective of social medicine. In this article I present the main conceptual and methodological aspects and the chief findings of my research over the past 15 years. Findings include a quantitative description of the current situation and the introduction of the category of explanatory contexts as a contribution to the study of Colombian violence. The complexity and severity of this problem demand greater theoretical discussion, more plans for action and a faster transition between the two. Social medicine may make a growing contribution to this field.

Towards a Methodology for Identifying Program Constraints During Requirements Analysis

NASA Technical Reports Server (NTRS)

Romo, Lilly; Gates, Ann Q.; Della-Piana, Connie Kubo

1997-01-01

Requirements analysis is the activity that involves determining the needs of the customer, identifying the services that the software system should provide and understanding the constraints on the solution. The result of this activity is a natural language document, typically referred to as the requirements definition document. Some of the problems that exist in defining requirements in large scale software projects includes synthesizing knowledge from various domain experts and communicating this information across multiple levels of personnel. One approach that addresses part of this problem is called context monitoring and involves identifying the properties of and relationships between objects that the system will manipulate. This paper examines several software development methodologies, discusses the support that each provide for eliciting such information from experts and specifying the information, and suggests refinements to these methodologies.

Quantitative and qualitative approaches in educational research — problems and examples of controlled understanding through interpretive methods

NASA Astrophysics Data System (ADS)

Neumann, Karl

1987-06-01

In the methodological discussion of recent years it has become apparent that many research problems, including problems relating to the theory of educational science, cannot be solved by using quantitative methods. The multifaceted aspects of human behaviour and all its environment-bound subtle nuances, especially the process of education or the development of identity, cannot fully be taken into account within a rigid neopositivist approach. In employing the paradigm of symbolic interactionism as a suitable model for the analysis of processes of education and formation, the research has generally to start out from complex reciprocal social interactions instead of unambigious connections of causes. In analysing several particular methodological problems, the article demonstrates some weaknesses of quantitative approaches and then shows the advantages in and the necessity for using qualitative research tools.

Design space pruning heuristics and global optimization method for conceptual design of low-thrust asteroid tour missions

NASA Astrophysics Data System (ADS)

Alemany, Kristina

Electric propulsion has recently become a viable technology for spacecraft, enabling shorter flight times, fewer required planetary gravity assists, larger payloads, and/or smaller launch vehicles. With the maturation of this technology, however, comes a new set of challenges in the area of trajectory design. Because low-thrust trajectory optimization has historically required long run-times and significant user-manipulation, mission design has relied on expert-based knowledge for selecting departure and arrival dates, times of flight, and/or target bodies and gravitational swing-bys. These choices are generally based on known configurations that have worked well in previous analyses or simply on trial and error. At the conceptual design level, however, the ability to explore the full extent of the design space is imperative to locating the best solutions in terms of mass and/or flight times. Beginning in 2005, the Global Trajectory Optimization Competition posed a series of difficult mission design problems, all requiring low-thrust propulsion and visiting one or more asteroids. These problems all had large ranges on the continuous variables---launch date, time of flight, and asteroid stay times (when applicable)---as well as being characterized by millions or even billions of possible asteroid sequences. Even with recent advances in low-thrust trajectory optimization, full enumeration of these problems was not possible within the stringent time limits of the competition. This investigation develops a systematic methodology for determining a broad suite of good solutions to the combinatorial, low-thrust, asteroid tour problem. The target application is for conceptual design, where broad exploration of the design space is critical, with the goal being to rapidly identify a reasonable number of promising solutions for future analysis. The proposed methodology has two steps. The first step applies a three-level heuristic sequence developed from the physics of the problem, which allows for efficient pruning of the design space. The second phase applies a global optimization scheme to locate a broad suite of good solutions to the reduced problem. The global optimization scheme developed combines a novel branch-and-bound algorithm with a genetic algorithm and an industry-standard low-thrust trajectory optimization program to solve for the following design variables: asteroid sequence, launch date, times of flight, and asteroid stay times. The methodology is developed based on a small sample problem, which is enumerated and solved so that all possible discretized solutions are known. The methodology is then validated by applying it to a larger intermediate sample problem, which also has a known solution. Next, the methodology is applied to several larger combinatorial asteroid rendezvous problems, using previously identified good solutions as validation benchmarks. These problems include the 2nd and 3rd Global Trajectory Optimization Competition problems. The methodology is shown to be capable of achieving a reduction in the number of asteroid sequences of 6-7 orders of magnitude, in terms of the number of sequences that require low-thrust optimization as compared to the number of sequences in the original problem. More than 70% of the previously known good solutions are identified, along with several new solutions that were not previously reported by any of the competitors. Overall, the methodology developed in this investigation provides an organized search technique for the low-thrust mission design of asteroid rendezvous problems.

Modeling, Analyzing, and Mitigating Dissonance Between Alerting Systems

NASA Technical Reports Server (NTRS)

Song, Lixia; Kuchar, James K.

2003-01-01

Alerting systems are becoming pervasive in process operations, which may result in the potential for dissonance or conflict in information from different alerting systems that suggests different threat levels and/or actions to resolve hazards. Little is currently available to help in predicting or solving the dissonance problem. This thesis presents a methodology to model and analyze dissonance between alerting systems, providing both a theoretical foundation for understanding dissonance and a practical basis from which specific problems can be addressed. A state-space representation of multiple alerting system operation is generalized that can be tailored across a variety of applications. Based on the representation, two major causes of dissonance are identified: logic differences and sensor error. Additionally, several possible types of dissonance are identified. A mathematical analysis method is developed to identify the conditions for dissonance originating from logic differences. A probabilistic analysis methodology is developed to estimate the probability of dissonance originating from sensor error, and to compare the relative contribution to dissonance of sensor error against the contribution from logic differences. A hybrid model, which describes the dynamic behavior of the process with multiple alerting systems, is developed to identify dangerous dissonance space, from which the process can lead to disaster. Methodologies to avoid or mitigate dissonance are outlined. Two examples are used to demonstrate the application of the methodology. First, a conceptual In-Trail Spacing example is presented. The methodology is applied to identify the conditions for possible dissonance, to identify relative contribution of logic difference and sensor error, and to identify dangerous dissonance space. Several proposed mitigation methods are demonstrated in this example. In the second example, the methodology is applied to address the dissonance problem between two air traffic alert and avoidance systems: the existing Traffic Alert and Collision Avoidance System (TCAS) vs. the proposed Airborne Conflict Management system (ACM). Conditions on ACM resolution maneuvers are identified to avoid dynamic dissonance between TCAS and ACM. Also included in this report is an Appendix written by Lee Winder about recent and continuing work on alerting systems design. The application of Markov Decision Process (MDP) theory to complex alerting problems is discussed and illustrated with an abstract example system.

Maximum Entropy/Optimal Projection (MEOP) control design synthesis: Optimal quantification of the major design tradeoffs

NASA Technical Reports Server (NTRS)

Hyland, D. C.; Bernstein, D. S.

1987-01-01

The underlying philosophy and motivation of the optimal projection/maximum entropy (OP/ME) stochastic modeling and reduced control design methodology for high order systems with parameter uncertainties are discussed. The OP/ME design equations for reduced-order dynamic compensation including the effect of parameter uncertainties are reviewed. The application of the methodology to several Large Space Structures (LSS) problems of representative complexity is illustrated.

A methodological proposal for the development of an HPC-based antenna array scheduler

NASA Astrophysics Data System (ADS)

Bonvallet, Roberto; Hoffstadt, Arturo; Herrera, Diego; López, Daniela; Gregorio, Rodrigo; Almuna, Manuel; Hiriart, Rafael; Solar, Mauricio

2010-07-01

As new astronomy projects choose interferometry to improve angular resolution and to minimize costs, preparing and optimizing schedules for an antenna array becomes an increasingly critical task. This problem shares similarities with the job-shop problem, which is known to be a NP-hard problem, making a complete approach infeasible. In the case of ALMA, 18000 projects per season are expected, and the best schedule must be found in the order of minutes. The problem imposes severe difficulties: the large domain of observation projects to be taken into account; a complex objective function, composed of several abstract, environmental, and hardware constraints; the number of restrictions imposed and the dynamic nature of the problem, as weather is an ever-changing variable. A solution can benefit from the use of High-Performance Computing for the final implementation to be deployed, but also for the development process. Our research group proposes the use of both metaheuristic search and statistical learning algorithms, in order to create schedules in a reasonable time. How these techniques will be applied is yet to be determined as part of the ongoing research. Several algorithms need to be implemented, tested and evaluated by the team. This work presents the methodology proposed to lead the development of the scheduler. The basic functionality is encapsulated into software components implemented on parallel architectures. These components expose a domain-level interface to the researchers, enabling then to develop early prototypes for evaluating and comparing their proposed techniques.

An overview of maternal separation effects on behavioural outcomes in mice: Evidence from a four-stage methodological systematic review.

PubMed

Tractenberg, Saulo G; Levandowski, Mateus L; de Azeredo, Lucas Araújo; Orso, Rodrigo; Roithmann, Laura G; Hoffmann, Emerson S; Brenhouse, Heather; Grassi-Oliveira, Rodrigo

2016-09-01

Early life stress (ELS) developmental effects have been widely studied by preclinical researchers. Despite the growing body of evidence from ELS models, such as the maternal separation paradigm, the reported results have marked inconsistencies. The maternal separation model has several methodological pitfalls that could influence the reliability of its results. Here, we critically review 94 mice studies that addressed the effects of maternal separation on behavioural outcomes. We also discuss methodological issues related to the heterogeneity of separation protocols and the quality of reporting methods. Our findings indicate a lack of consistency in maternal separation effects: major studies of behavioural and biological phenotypes failed to find significant deleterious effects. Furthermore, we identified several specific variations in separation methodological procedures. These methodological variations could contribute to the inconsistency of maternal separation effects by producing different degrees of stress exposure in maternal separation-reared pups. These methodological problems, together with insufficient reporting, might lead to inaccurate and unreliable effect estimates in maternal separation studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Restoration of a single superresolution image from several blurred, noisy, and undersampled measured images.

PubMed

Elad, M; Feuer, A

1997-01-01

The three main tools in the single image restoration theory are the maximum likelihood (ML) estimator, the maximum a posteriori probability (MAP) estimator, and the set theoretic approach using projection onto convex sets (POCS). This paper utilizes the above known tools to propose a unified methodology toward the more complicated problem of superresolution restoration. In the superresolution restoration problem, an improved resolution image is restored from several geometrically warped, blurred, noisy and downsampled measured images. The superresolution restoration problem is modeled and analyzed from the ML, the MAP, and POCS points of view, yielding a generalization of the known superresolution restoration methods. The proposed restoration approach is general but assumes explicit knowledge of the linear space- and time-variant blur, the (additive Gaussian) noise, the different measured resolutions, and the (smooth) motion characteristics. A hybrid method combining the simplicity of the ML and the incorporation of nonellipsoid constraints is presented, giving improved restoration performance, compared with the ML and the POCS approaches. The hybrid method is shown to converge to the unique optimal solution of a new definition of the optimization problem. Superresolution restoration from motionless measurements is also discussed. Simulations demonstrate the power of the proposed methodology.

The kidney allocation score: methodological problems, moral concerns and unintended consequences.

PubMed

Hippen, B

2009-07-01

The growing disparity between the demand for and supply of kidneys for transplantation has generated interest in alternative systems of allocating kidneys from deceased donors. This personal viewpoint focuses attention on the Kidney Allocation Score (KAS) proposal promulgated by the UNOS/OPTN Kidney Committee. I identify several methodological and moral flaws in the proposed system, concluding that any iteration of the KAS proposal should be met with more skepticism than sanguinity.

Software Risk Identification for Interplanetary Probes

NASA Technical Reports Server (NTRS)

Dougherty, Robert J.; Papadopoulos, Periklis E.

2005-01-01

The need for a systematic and effective software risk identification methodology is critical for interplanetary probes that are using increasingly complex and critical software. Several probe failures are examined that suggest more attention and resources need to be dedicated to identifying software risks. The direct causes of these failures can often be traced to systemic problems in all phases of the software engineering process. These failures have lead to the development of a practical methodology to identify risks for interplanetary probes. The proposed methodology is based upon the tailoring of the Software Engineering Institute's (SEI) method of taxonomy-based risk identification. The use of this methodology will ensure a more consistent and complete identification of software risks in these probes.

Decision-theoretic methodology for reliability and risk allocation in nuclear power plants

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

Cho, N.Z.; Papazoglou, I.A.; Bari, R.A.

1985-01-01

This paper describes a methodology for allocating reliability and risk to various reactor systems, subsystems, components, operations, and structures in a consistent manner, based on a set of global safety criteria which are not rigid. The problem is formulated as a multiattribute decision analysis paradigm; the multiobjective optimization, which is performed on a PRA model and reliability cost functions, serves as the guiding principle for reliability and risk allocation. The concept of noninferiority is used in the multiobjective optimization problem. Finding the noninferior solution set is the main theme of the current approach. The assessment of the decision maker's preferencesmore » could then be performed more easily on the noninferior solution set. Some results of the methodology applications to a nontrivial risk model are provided and several outstanding issues such as generic allocation and preference assessment are discussed.« less

Development of Methodology for Programming Autonomous Agents

NASA Technical Reports Server (NTRS)

Erol, Kutluhan; Levy, Renato; Lang, Lun

2004-01-01

A brief report discusses the rationale for, and the development of, a methodology for generating computer code for autonomous-agent-based systems. The methodology is characterized as enabling an increase in the reusability of the generated code among and within such systems, thereby making it possible to reduce the time and cost of development of the systems. The methodology is also characterized as enabling reduction of the incidence of those software errors that are attributable to the human failure to anticipate distributed behaviors caused by the software. A major conceptual problem said to be addressed in the development of the methodology was that of how to efficiently describe the interfaces between several layers of agent composition by use of a language that is both familiar to engineers and descriptive enough to describe such interfaces unambivalently

Methodologie de la classe de conversation: Vers un enseignement de la competence a communiquer. (Methodology of the Conversation Class: Toward Education in Communicative Competence).

ERIC Educational Resources Information Center

Perez, Marcel

This study presents a model for teaching a French conversation course on the college level. The research is based on French language classes in Quebec general education and professional colleges (CEGEP). The first part states the problem, examines several programs, describes the organization of the conversation classes, presents several language…

Metropolitan Forensic Anthropology Team (MFAT) studies in identification: 1. Race and sex assessment by discriminant function analysis of the postcranial skeleton.

PubMed

Taylor, J V; DiBennardo, R; Linares, G H; Goldman, A D; DeForest, P R

1984-07-01

A case study is presented to demonstrate the utility of the team approach to the identification of human remains, and to illustrate a methodological innovation developed by MFAT. Case 1 represents the first of several planned case studies, each designed to present new methodological solutions to standard problems in identification. The present case describes a test, by application, of race and sex assessment of the postcranial skeleton by discriminant function analysis.

Innovative Technologies for Multicultural Education Needs

ERIC Educational Resources Information Center

Ferdig, Richard E.; Coutts, Jade; DiPietro, Joseph; Lok, Benjamin; Davis, Niki

2007-01-01

Purpose: The purpose of this paper is to discuss several technology applications that are being used to address current problems or opportunities related to multicultural education. Design/methodology/approach: Five technology applications or technology-related projects are discussed, including a teacher education literacy tool, social networking…

A review of temporal effects and outcome predictors in substance abuse treatment studies with long-term follow-ups. Preliminary results and methodological issues.

PubMed

McKay, J R; Weiss, R V

2001-04-01

This article is an initial report from a review of alcohol and drug treatment studies with follow-ups of 2 years or more. The goals of the review are to examine the stability of substance use outcomes and the factors that moderate or mediate these outcomes. Results from 12 studies that generated multiple research reports are presented, and methodological problems encountered in the review are discussed. Substance use outcomes at the group level were generally stable, although moderate within-subject variation in substance use status over time was observed. Of factors assessed at baseline, psychiatric severity was a significant predictor of outcome in the highest percentage of reports, although the nature of the relationship varied. Stronger motivation and coping at baseline also consistently predicted better drinking outcomes. Better progress while in treatment, and the performance of pro-recovery behaviors and low problem severity in associated areas following treatment, consistently predicted better substance use outcomes.

Fuzzy Multi-Objective Vendor Selection Problem with Modified S-CURVE Membership Function

NASA Astrophysics Data System (ADS)

Díaz-Madroñero, Manuel; Peidro, David; Vasant, Pandian

2010-06-01

In this paper, the S-Curve membership function methodology is used in a vendor selection (VS) problem. An interactive method for solving multi-objective VS problems with fuzzy goals is developed. The proposed method attempts simultaneously to minimize the total order costs, the number of rejected items and the number of late delivered items with reference to several constraints such as meeting buyers' demand, vendors' capacity, vendors' quota flexibility, vendors' allocated budget, etc. We compare in an industrial case the performance of S-curve membership functions, representing uncertainty goals and constraints in VS problems, with linear membership functions.

PTSD Symptom Severities, Interpersonal Traumas, and Benzodiazepines Are Associated with Substance-Related Problems in Trauma Patients

PubMed Central

Guina, Jeffrey; Nahhas, Ramzi W.; Goldberg, Adam J.; Farnsworth, Seth

2016-01-01

Background: Trauma is commonly associated with substance-related problems, yet associations between specific substances and specific posttraumatic stress disorder symptoms (PTSSs) are understudied. We hypothesized that substance-related problems are associated with PTSS severities, interpersonal traumas, and benzodiazepine prescriptions. Methods: Using a cross-sectional survey methodology in a consecutive sample of adult outpatients with trauma histories (n = 472), we used logistic regression to examine substance-related problems in general (primary, confirmatory analysis), as well as alcohol, tobacco, and illicit drug problems specifically (secondary, exploratory analyses) in relation to demographics, trauma type, PTSSs, and benzodiazepine prescriptions. Results: After adjusting for multiple testing, several factors were significantly associated with substance-related problems, particularly benzodiazepines (AOR = 2.78; 1.99 for alcohol, 2.42 for tobacco, 8.02 for illicit drugs), DSM-5 PTSD diagnosis (AOR = 1.92; 2.38 for alcohol, 2.00 for tobacco, 2.14 for illicit drugs), most PTSSs (especially negative beliefs, recklessness, and avoidance), and interpersonal traumas (e.g., assaults and child abuse). Conclusion: In this clinical sample, there were consistent and strong associations between several trauma-related variables and substance-related problems, consistent with our hypotheses. We discuss possible explanations and implications of these findings, which we hope will stimulate further research, and improve screening and treatment. PMID:27517964

The inverse problem of brain energetics: ketone bodies as alternative substrates

NASA Astrophysics Data System (ADS)

Calvetti, D.; Occhipinti, R.; Somersalo, E.

2008-07-01

Little is known about brain energy metabolism under ketosis, although there is evidence that ketone bodies have a neuroprotective role in several neurological disorders. We investigate the inverse problem of estimating reaction fluxes and transport rates in the different cellular compartments of the brain, when the data amounts to a few measured arterial venous concentration differences. By using a recently developed methodology to perform Bayesian Flux Balance Analysis and a new five compartment model of the astrocyte-glutamatergic neuron cellular complex, we are able to identify the preferred biochemical pathways during shortage of glucose and in the presence of ketone bodies in the arterial blood. The analysis is performed in a minimally biased way, therefore revealing the potential of this methodology for hypothesis testing.

A Comparison of Methods to Analyze Aquatic Heterotrophic Flagellates of Different Taxonomic Groups.

PubMed

Jeuck, Alexandra; Nitsche, Frank; Wylezich, Claudia; Wirth, Olaf; Bergfeld, Tanja; Brutscher, Fabienne; Hennemann, Melanie; Monir, Shahla; Scherwaß, Anja; Troll, Nicole; Arndt, Hartmut

2017-08-01

Heterotrophic flagellates contribute significantly to the matter flux in aquatic and terrestrial ecosystems. Still today their quantification and taxonomic classification bear several problems in field studies, though these methodological problems seem to be increasingly ignored in current ecological studies. Here we describe and test different methods, the live-counting technique, different fixation techniques, cultivation methods like the liquid aliquot method (LAM), and a molecular single cell survey called aliquot PCR (aPCR). All these methods have been tested either using aquatic field samples or cultures of freshwater and marine taxa. Each of the described methods has its advantages and disadvantages, which have to be considered in every single case. With the live-counting technique a detection of living cells up to morphospecies level is possible. Fixation of cells and staining methods are advantageous due to the possible long-term storage and observation of samples. Cultivation methods (LAM) offer the possibility of subsequent molecular analyses, and aPCR tools might complete the deficiency of LAM in terms of the missing detection of non-cultivable flagellates. In summary, we propose a combination of several investigation techniques reducing the gap between the different methodological problems. Copyright © 2017 Elsevier GmbH. All rights reserved.

Methodological difficulties of conducting agroecological studies from a statistical perspective

USDA-ARS?s Scientific Manuscript database

Statistical methods for analysing agroecological data might not be able to help agroecologists to solve all of the current problems concerning crop and animal husbandry, but such methods could well help agroecologists to assess, tackle, and resolve several agroecological issues in a more reliable an...

Challenging the Stereotypes of Mexican American Fathers

ERIC Educational Resources Information Center

Saracho, Olivia N.; Spodek, Bernard

2007-01-01

This critical review presents studies of Mexican American fathers in the United Sates to provide researchers with an understanding of contemporary fatherhood. It describes the myths that cause methodological and conceptual problems in interpreting the results of studies on Mexican American fathers. Several common challenges and limitations in…

Reliability based design optimization: Formulations and methodologies

NASA Astrophysics Data System (ADS)

Agarwal, Harish

Modern products ranging from simple components to complex systems should be designed to be optimal and reliable. The challenge of modern engineering is to ensure that manufacturing costs are reduced and design cycle times are minimized while achieving requirements for performance and reliability. If the market for the product is competitive, improved quality and reliability can generate very strong competitive advantages. Simulation based design plays an important role in designing almost any kind of automotive, aerospace, and consumer products under these competitive conditions. Single discipline simulations used for analysis are being coupled together to create complex coupled simulation tools. This investigation focuses on the development of efficient and robust methodologies for reliability based design optimization in a simulation based design environment. Original contributions of this research are the development of a novel efficient and robust unilevel methodology for reliability based design optimization, the development of an innovative decoupled reliability based design optimization methodology, the application of homotopy techniques in unilevel reliability based design optimization methodology, and the development of a new framework for reliability based design optimization under epistemic uncertainty. The unilevel methodology for reliability based design optimization is shown to be mathematically equivalent to the traditional nested formulation. Numerical test problems show that the unilevel methodology can reduce computational cost by at least 50% as compared to the nested approach. The decoupled reliability based design optimization methodology is an approximate technique to obtain consistent reliable designs at lesser computational expense. Test problems show that the methodology is computationally efficient compared to the nested approach. A framework for performing reliability based design optimization under epistemic uncertainty is also developed. A trust region managed sequential approximate optimization methodology is employed for this purpose. Results from numerical test studies indicate that the methodology can be used for performing design optimization under severe uncertainty.

Alcohol and drug treatment outcome studies: new methodological review (2005-2010) and comparison with past reviews.

PubMed

Robinson, Sean M; Sobell, Linda Carter; Sobell, Mark B; Arcidiacono, Steven; Tzall, David

2014-01-01

Several methodological reviews of alcohol treatment outcome studies and one review of drug studies have been published over the past 40 years. Although past reviews demonstrated methodological improvements in alcohol studies, they also found continued deficiencies. The current review allows for an updated evaluation of the methodological rigor of alcohol and drug studies and, by utilizing inclusion criteria similar to previous reviews, it allows for a comparative review over time. In addition, this is the first review that compares the methodology of alcohol and drug treatment outcome studies published during the same time period. The methodology for 25 alcohol and 11 drug treatment outcome studies published from 2005 through 2010 that met the review's inclusion criteria was evaluated. The majority of variables evaluated were used in prior reviews. The current review found that more alcohol and drug treatment outcome studies are now using continuous substance use measures and assessing problem severity. Although there have been methodological improvements over time, the current reviews differed little from their most recent past counterpart. Despite this finding, some areas, particularly the continued low reporting of demographic data, needs strengthening. Improvement in the methodological rigor of alcohol and drug treatment outcome studies has occurred over time. The current review found few differences between alcohol and drug study methodologies as well as few differences between the current review and the most recent past alcohol and drug reviews. © 2013 Elsevier Ltd. All rights reserved.

Perspectives for Teachers of Latin American Culture.

ERIC Educational Resources Information Center

Seelye, H. Ned, Ed.

Articles treating various aspects of the teaching of Hispanic culture at the secondary and junior high school levels are intended to improve methodology and facilitate the development of teacher-made instructional materials. An overview of the field relating problems and procedures in several areas is developed. Selections cover: (1) bilinguality,…

Manual for the Comparative Politics Laboratory: Conditions for Effective Democracy.

ERIC Educational Resources Information Center

Fogelman, Edwin; Zingale, Nancy

This manual introduces undergraduate students in political science to major types of data and methods for cross-national quantitative analysis. The manual's topic, Conditions for Effective Democracy, was chosen because it incorporates several different kinds of data and illustrates various methodological problems. The data are cross-sectional…

False-Positive Tangible Outcomes of Functional Analyses

ERIC Educational Resources Information Center

Rooker, Griffin W.; Iwata, Brian A.; Harper, Jill M.; Fahmie, Tara A.; Camp, Erin M.

2011-01-01

Functional analysis (FA) methodology is the most precise method for identifying variables that maintain problem behavior. Occasionally, however, results of an FA may be influenced by idiosyncratic sensitivity to aspects of the assessment conditions. For example, data from several studies suggest that inclusion of a tangible condition during an FA…

Emerging Models of the New Paradigm.

ERIC Educational Resources Information Center

Howser, Lee; Schwinn, Carole

Working with the Philadelphia-based Institute of Interactive Management, several teams at Jackson Community College (JCC), in Michigan, set out in 1994 to learn and apply an interactive design methodology to selected college subsystems. Interactive design begins with understanding problems faced by the system as a whole, which in the case of JCC…

Composite Indices of Development and Poverty: An Application to MDGs

ERIC Educational Resources Information Center

De Muro, Pasquale; Mazziotta, Matteo; Pareto, Adriano

2011-01-01

The measurement of development or poverty as multidimensional phenomena is very difficult because there are several theoretical, methodological and empirical problems involved. The literature of composite indicators offers a wide variety of aggregation methods, all with their pros and cons. In this paper, we propose a new, alternative composite…

Anticipating the Chaotic Behaviour of Industrial Systems Based on Stochastic, Event-Driven Simulations

NASA Astrophysics Data System (ADS)

Bruzzone, Agostino G.; Revetria, Roberto; Simeoni, Simone; Viazzo, Simone; Orsoni, Alessandra

2004-08-01

In logistics and industrial production managers must deal with the impact of stochastic events to improve performances and reduce costs. In fact, production and logistics systems are generally designed considering some parameters as deterministically distributed. While this assumption is mostly used for preliminary prototyping, it is sometimes also retained during the final design stage, and especially for estimated parameters (i.e. Market Request). The proposed methodology can determine the impact of stochastic events in the system by evaluating the chaotic threshold level. Such an approach, based on the application of a new and innovative methodology, can be implemented to find the condition under which chaos makes the system become uncontrollable. Starting from problem identification and risk assessment, several classification techniques are used to carry out an effect analysis and contingency plan estimation. In this paper the authors illustrate the methodology with respect to a real industrial case: a production problem related to the logistics of distributed chemical processing.

Seismic Hazard Estimates Using Ill-defined Macroseismic Data at Site

NASA Astrophysics Data System (ADS)

Albarello, D.; Mucciarelli, M.

- A new approach is proposed to the seismic hazard estimate based on documentary data concerning local history of seismic effects. The adopted methodology allows for the use of ``poor'' data, such as the macroseismic ones, within a formally coherent approach that permits overcoming a number of problems connected to the forcing of available information in the frame of ``standard'' methodologies calibrated on the use of instrumental data. The use of the proposed methodology allows full exploitation of all the available information (that for many towns in Italy covers several centuries) making possible a correct use of macroseismic data characterized by different levels of completeness and reliability. As an application of the proposed methodology, seismic hazard estimates are presented for two towns located in Northern Italy: Bologna and Carpi.

Constructing space difference schemes which satisfy a cell entropy inequality

NASA Technical Reports Server (NTRS)

Merriam, Marshal L.

1989-01-01

A numerical methodology for solving convection problems is presented, using finite difference schemes which satisfy the second law of thermodynamics on a cell-by-cell basis in addition to the usual conservation laws. It is shown that satisfaction of a cell entropy inequality is sufficient, in some cases, to guarantee nonlinear stability. Some details are given for several one-dimensional problems, including the quasi-one-dimensional Euler equations applied to flow in a nozzle.

Accurate quantum chemical calculations

NASA Technical Reports Server (NTRS)

Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

1989-01-01

An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.

Environment, genes, and experience: lessons from behavior genetics.

PubMed

Barsky, Philipp I

2010-11-01

The article reviews the theoretical analysis of the problems inherent in studying the environment within behavior genetics across several periods in the development of environmental studies in behavior genetics and proposes some possible alternatives to traditional approaches to studying the environment in behavior genetics. The first period (from the end of the 1920s to the end of the 1970s), when the environment was not actually studied, is called pre-environmental; during this time, the basic principles and theoretical models of understanding environmental effects in behavior genetics were developed. The second period is characterized by the development of studies on environmental influences within the traditional behavior genetics paradigm; several approaches to studying the environment emerged in behavior genetics during this period, from the beginning of the 1980s until today. At the present time, the field is undergoing paradigmatic changes, concerned with methodology, theory, and mathematical models of genotype-environment interplay; this might be the beginning of a third period of development of environmental studies in behavior genetics. In another part, the methodological problems related to environmental studies in behavior genetics are discussed. Although the methodology used in differential psychology is applicable for assessment of differences between individuals, it is insufficient to explain the sources of these differences. In addition, we stress that psychoanalytic studies of twins and their experiences, initiated in the 1930s and continued episodically until the 1980s, could bring an interesting methodology and contribute to the explanation of puzzling findings from environmental studies of behavior genetics. Finally, we will conclude with implications from the results of environmental studies in behavior genetics, including methodological issues. Copyright © 2010 Elsevier Ltd. All rights reserved.

Short-Term fo F2 Forecast: Present Day State of Art

NASA Astrophysics Data System (ADS)

Mikhailov, A. V.; Depuev, V. H.; Depueva, A. H.

An analysis of the F2-layer short-term forecast problem has been done. Both objective and methodological problems prevent us from a deliberate F2-layer forecast issuing at present. An empirical approach based on statistical methods may be recommended for practical use. A forecast method based on a new aeronomic index (a proxy) AI has been proposed and tested over selected 64 severe storm events. The method provides an acceptable prediction accuracy both for strongly disturbed and quiet conditions. The problems with the prediction of the F2-layer quiet-time disturbances as well as some other unsolved problems are discussed

Common Methodological Problems in Research on the Addictions.

ERIC Educational Resources Information Center

Nathan, Peter E.; Lansky, David

1978-01-01

Identifies common problems in research on the addictions and offers suggestions for remediating these methodological problems. The addictions considered include alcoholism and drug dependencies. Problems considered are those arising from inadequate, incomplete, or biased reviews of relevant literatures and methodological shortcomings of subject…

Common methodological flaws in economic evaluations.

PubMed

Drummond, Michael; Sculpher, Mark

2005-07-01

Economic evaluations are increasingly being used by those bodies such as government agencies and managed care groups that make decisions about the reimbursement of health technologies. However, several reviews of economic evaluations point to numerous deficiencies in the methodology of studies or the failure to follow published methodological guidelines. This article, written for healthcare decision-makers and other users of economic evaluations, outlines the common methodological flaws in studies, focussing on those issues that are likely to be most important when deciding on the reimbursement, or guidance for use, of health technologies. The main flaws discussed are: (i) omission of important costs or benefits; (ii) inappropriate selection of alternatives for comparison; (iii) problems in making indirect comparisons; (iv) inadequate representation of the effectiveness data; (v) inappropriate extrapolation beyond the period observed in clinical studies; (vi) excessive use of assumptions rather than data; (vii) inadequate characterization of uncertainty; (viii) problems in aggregation of results; (ix) reporting of average cost-effectiveness ratios; (x) lack of consideration of generalizability issues; and (xi) selective reporting of findings. In each case examples are given from the literature and guidance is offered on how to detect flaws in economic evaluations.

Applying Bayesian statistics to the study of psychological trauma: A suggestion for future research.

PubMed

Yalch, Matthew M

2016-03-01

Several contemporary researchers have noted the virtues of Bayesian methods of data analysis. Although debates continue about whether conventional or Bayesian statistics is the "better" approach for researchers in general, there are reasons why Bayesian methods may be well suited to the study of psychological trauma in particular. This article describes how Bayesian statistics offers practical solutions to the problems of data non-normality, small sample size, and missing data common in research on psychological trauma. After a discussion of these problems and the effects they have on trauma research, this article explains the basic philosophical and statistical foundations of Bayesian statistics and how it provides solutions to these problems using an applied example. Results of the literature review and the accompanying example indicates the utility of Bayesian statistics in addressing problems common in trauma research. Bayesian statistics provides a set of methodological tools and a broader philosophical framework that is useful for trauma researchers. Methodological resources are also provided so that interested readers can learn more. (c) 2016 APA, all rights reserved).

Does Anxiety Modify the Risk for, or Severity of, Conduct Problems Among Children With Co-Occurring ADHD: Categorical and Dimensional and Analyses.

PubMed

Danforth, Jeffrey S; Doerfler, Leonard A; Connor, Daniel F

2017-08-01

The goal was to examine whether anxiety modifies the risk for, or severity of, conduct problems in children with ADHD. Assessment included both categorical and dimensional measures of ADHD, anxiety, and conduct problems. Analyses compared conduct problems between children with ADHD features alone versus children with co-occurring ADHD and anxiety features. When assessed by dimensional rating scales, results showed that compared with children with ADHD alone, those children with ADHD co-occurring with anxiety are at risk for more intense conduct problems. When assessment included a Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) diagnosis via the Schedule for Affective Disorders and Schizophrenia for School Age Children-Epidemiologic Version (K-SADS), results showed that compared with children with ADHD alone, those children with ADHD co-occurring with anxiety neither had more intense conduct problems nor were they more likely to be diagnosed with oppositional defiant disorder or conduct disorder. Different methodological measures of ADHD, anxiety, and conduct problem features influenced the outcome of the analyses.

Functional approximation using artificial neural networks in structural mechanics

NASA Technical Reports Server (NTRS)

Alam, Javed; Berke, Laszlo

1993-01-01

The artificial neural networks (ANN) methodology is an outgrowth of research in artificial intelligence. In this study, the feed-forward network model that was proposed by Rumelhart, Hinton, and Williams was applied to the mapping of functions that are encountered in structural mechanics problems. Several different network configurations were chosen to train the available data for problems in materials characterization and structural analysis of plates and shells. By using the recall process, the accuracy of these trained networks was assessed.

A Different Approach to the Generation of Patient Management Problems from a Knowledge-Based System

PubMed Central

Barriga, Rosa Maria

1988-01-01

Several strategies are proposed to approach the generation of Patient Management Problems from a Knowledge Base and avoid inconsistencies in the results. These strategies are based on a different Knowledge Base structure and in the use of case introductions that describe the patient attributes which are not disease-dependent. This methodology has proven effective in a recent pilot test and it is on its way to implementation as part of an educational program at CWRU, School of Medicine.

What Can Be Learned from a Laboratory Model of Conceptual Change? Descriptive Findings and Methodological Issues

ERIC Educational Resources Information Center

Ohlsson, Stellan; Cosejo, David G.

2014-01-01

The problem of how people process novel and unexpected information--"deep learning" (Ohlsson in "Deep learning: how the mind overrides experience." Cambridge University Press, New York, 2011)--is central to several fields of research, including creativity, belief revision, and conceptual change. Researchers have not converged…

Mixed Methods Research: What Are the Key Issues to Consider?

ERIC Educational Resources Information Center

Ghosh, Rajashi

2016-01-01

Mixed methods research (MMR) is increasingly becoming a popular methodological approach in several fields due to the promise it holds for comprehensive understanding of complex problems being researched. However, researchers interested in MMR often lack reference to a guide that can explain the key issues pertaining to the paradigm wars…

Training School Personnel on Implementation of Check-in--Check-out Behavioral Interventions

ERIC Educational Resources Information Center

Ruiz, Maria Isolina

2012-01-01

Over the last several years, educational policy has advocated for a preventive approach to keep problem behaviors from escalating and interfering with student achievement. Proactive methodologies such as school-wide positive behavior support (SWPBS) and response to intervention (RTI) have become common practice in school districts across the…

Assessing the Impact of Planned Social Change. Occasional Paper Series, #8.

ERIC Educational Resources Information Center

Campbell, Donald T.

Program impact methodology--usually referred to as evaluation research--is described as it is developing in the United States. Several problems face the field of evaluation research. First, those issues grouped as "meta-scientific" include: (1) the distinction between qualitative and quantitative studies; (2) the separation of implementation and…

Is Acculturation in Hispanic Health Research a Flawed Concept? JSRI Working Paper.

ERIC Educational Resources Information Center

Ponce, Carlos; Comer, Brendon

Some health researchers have used the concept of acculturation to explain health behaviors or illnesses prevalent among Hispanic people. This paper reviews studies in health, educational, and social science research among Hispanics and argues that acculturation studies are seriously limited by several basic conceptual and methodological problems.…

An Overview of Integrated Logistic Support in Medical Material Programs.

DTIC Science & Technology

1980-12-01

OF MEDICAL INTEGRATED LOGISTIC SUPPORT ----------------- 7 B. PROBLEM DEFINITION AND OBJECTIVE ------------ 9 C. GENERAL APPROACH AND METHODOLOGY...SYSTEM ---------------------- 61 C. GENERAL CONCLUSIONS ------------------------- 63 D. RECOMMENDATIONS ----------------------------- 73 E. CONCLUSION...21 Technological advancement has caused major changes in medicine and dentistry in the last several decades. Inten- sive care units, computerized axial

Brain Oscillations Forever--Neurophysiology in Future Research of Child Psychiatric Problems

ERIC Educational Resources Information Center

Rothenberger, Aribert

2009-01-01

For decades neurophysiology has successfully contributed to research and clinical care in child psychiatry. Recently, methodological progress has led to a revival of interest in brain oscillations (i.e., a band of periodic neuronal frequencies with a wave-duration from milliseconds to several seconds which may code and decode information). These…

Measurement tools for mental health problems and mental well-being in people with severe or profound intellectual disabilities: A systematic review.

PubMed

Flynn, Samantha; Vereenooghe, Leen; Hastings, Richard P; Adams, Dawn; Cooper, Sally-Ann; Gore, Nick; Hatton, Chris; Hood, Kerry; Jahoda, Andrew; Langdon, Peter E; McNamara, Rachel; Oliver, Chris; Roy, Ashok; Totsika, Vasiliki; Waite, Jane

2017-11-01

Mental health problems affect people with intellectual disabilities (ID) at rates similar to or in excess of the non-ID population. People with severe ID are likely to have persistent mental health problems. In this systematic review (PROSPERO 2015:CRD42015024469), we identify and evaluate the methodological quality of available measures of mental health problems or well-being in individuals with severe or profound ID. Electronic searches of ten databases identified relevant publications. Two reviewers independently reviewed titles and abstracts of retrieved records (n=41,232) and full-text articles (n=573). Data were extracted and the quality of included papers was appraised. Thirty-two papers reporting on 12 measures were included. Nine measures addressed a broad spectrum of mental health problems, and were largely observational. One physiological measure of well-being was included. The Aberrant Behavior Checklist, Diagnostic Assessment for the Severely Handicapped Scale-II and Mood, Interest and Pleasure Questionnaire are reliable measures in this population. However, the psychometric properties of six other measures were only considered within a single study - indicating a lack of research replication. Few mental health measures are available for people with severe or profound ID, particularly lacking are tools measuring well-being. Assessment methods that do not rely on proxy reports should be explored further. Copyright © 2017 Elsevier Ltd. All rights reserved.

How to investigate neuro-biochemical relationships on a regional level in humans? Methodological considerations for combining functional with biochemical imaging.

PubMed

Duncan, Niall W; Wiebking, Christine; Muñoz-Torres, Zeidy; Northoff, Georg

2014-01-15

There is an increasing interest in combining different imaging modalities to investigate the relationship between neural and biochemical activity. More specifically, imaging techniques like MRS and PET that allow for biochemical measurement are combined with techniques like fMRI and EEG that measure neural activity in different states. Such combination of neural and biochemical measures raises not only technical issues, such as merging the different data sets, but also several methodological issues. These methodological issues – ranging from hypothesis generation and hypothesis-guided use of technical facilities to target measures and experimental measures – are the focus of this paper. We discuss the various methodological problems and issues raised by the combination of different imaging methodologies in order to investigate neuro-biochemical relationships on a regional level in humans. For example, the choice of transmitter and scan type is discussed, along with approaches to allow the establishment of particular specificities (such as regional or biochemical) to in turn make results fully interpretable. An algorithm that can be used as a form of checklist for designing such multimodal studies is presented. The paper concludes that while several methodological and technical caveats needs to be overcome and addressed, multimodal imaging of the neuro-biochemical relationship provides an important tool to better understand the physiological mechanisms of the human brain.

How to investigate neuro-biochemical relationships on a regional level in humans? Methodological considerations for combining functional with biochemical imaging.

PubMed

Duncan, Niall W; Wiebking, Christine; Munoz-Torres, Zeidy; Northoff, Georg

2013-10-25

There is an increasing interest in combining different imaging modalities to investigate the relationship between neural and biochemical activity. More specifically, imaging techniques like MRS and PET that allow for biochemical measurement are combined with techniques like fMRI and EEG that measure neural activity in different states. Such combination of neural and biochemical measures raises not only technical issues, such as merging the different data sets, but also several methodological issues. These methodological issues - ranging from hypothesis generation and hypothesis-guided use of technical facilities to target measures and experimental measures - are the focus of this paper. We discuss the various methodological problems and issues raised by the combination of different imaging methodologies in order to investigate neuro-biochemical relationships on a regional level in humans. For example, the choice of transmitter and scan type is discussed, along with approaches to allow the establishment of particular specificities (such as regional or biochemical) to in turn make results fully interpretable. An algorithm that can be used as a form of checklist for designing such multimodal studies is presented. The paper concludes that while several methodological and technical caveats needs to be overcome and addressed, multimodal imaging of the neuro-biochemical relationship provides an important tool to better understand the physiological mechanisms of the human brain. Copyright © 2013. Published by Elsevier B.V.

Travel into a fairy land: a critique of modern qualitative and mixed methods psychologies.

PubMed

Toomela, Aaro

2011-03-01

In this article modern qualitative and mixed methods approaches are criticized from the standpoint of structural-systemic epistemology. It is suggested that modern qualitative methodologies suffer from several fallacies: some of them are grounded on inherently contradictory epistemology, the others ask scientific questions after the methods have been chosen, conduct studies inductively so that not only answers but even questions are often supposed to be discovered, do not create artificial situations and constraints on study-situations, are adevelopmental by nature, study not the external things and phenomena but symbols and representations--often the object of studies turns out to be the researcher rather than researched, rely on ambiguous data interpretation methods based to a large degree on feelings and opinions, aim to understand unique which is theoretically impossible, or have theoretical problems with sampling. Any one of these fallacies would be sufficient to exclude any possibility to achieve structural-systemic understanding of the studied things and phenomena. It also turns out that modern qualitative methodologies share several fallacies with the quantitative methodology. Therefore mixed methods approaches are not able to overcome the fundamental difficulties that characterize mixed methods taken separately. It is proposed that structural-systemic methodology that dominated psychological thought in the pre-WWII continental Europe is philosophically and theoretically better grounded than the other methodologies that can be distinguished in psychology today. Future psychology should be based on structural-systemic methodology.

Method for the Direct Solve of the Many-Body Schrödinger Wave Equation

NASA Astrophysics Data System (ADS)

Jerke, Jonathan; Tymczak, C. J.; Poirier, Bill

We report on theoretical and computational developments towards a computationally efficient direct solve of the many-body Schrödinger wave equation for electronic systems. This methodology relies on two recent developments pioneered by the authors: 1) the development of a Cardinal Sine basis for electronic structure calculations; and 2) the development of a highly efficient and compact representation of multidimensional functions using the Canonical tensor rank representation developed by Belykin et. al. which we have adapted to electronic structure problems. We then show several relevant examples of the utility and accuracy of this methodology, scaling with system size, and relevant convergence issues of the methodology. Method for the Direct Solve of the Many-Body Schrödinger Wave Equation.

Review of the probabilistic failure analysis methodology and other probabilistic approaches for application in aerospace structural design

NASA Technical Reports Server (NTRS)

Townsend, J.; Meyers, C.; Ortega, R.; Peck, J.; Rheinfurth, M.; Weinstock, B.

1993-01-01

Probabilistic structural analyses and design methods are steadily gaining acceptance within the aerospace industry. The safety factor approach to design has long been the industry standard, and it is believed by many to be overly conservative and thus, costly. A probabilistic approach to design may offer substantial cost savings. This report summarizes several probabilistic approaches: the probabilistic failure analysis (PFA) methodology developed by Jet Propulsion Laboratory, fast probability integration (FPI) methods, the NESSUS finite element code, and response surface methods. Example problems are provided to help identify the advantages and disadvantages of each method.

Conflict and the Common Good. Studies in Third World Societies, Publication Number Twenty-Four.

ERIC Educational Resources Information Center

Merrill, Robert S., Ed.; Willner, Dorothy, Ed.

The fundamental theme of these papers is what constitutes the common good and the issues and problems related to the understanding of that common good. Several anthropologists and a political scientist explore this theme in various geographic settings and from many theoretical and methodological perspectives. Among the countries and cultures…

The Use of Educational Platforms as Teaching Resource in Mathematics

ERIC Educational Resources Information Center

Gómez-Zermeño, Marcela; Franco-Gutiérrez, Héctor

2018-01-01

Dropping out from the school system at High School level has been a problem for several years; high levels of mathematics' failing have been a recurring situation. This paper discusses how academic virtual counseling might be a tool to help students in math class. The methodological approach is based in the non-experimental, longitudinal model…

Class Size and Student Performance at a Public Research University: A Cross-Classified Model

ERIC Educational Resources Information Center

Johnson, Iryna Y.

2010-01-01

This study addresses several methodological problems that have confronted prior research on the effect of class size on student achievement. Unlike previous studies, this analysis accounts for the hierarchical data structure of student achievement, where grades are nested within classes and students, and considers a wide range of class sizes…

Neurophenomenology revisited: second-person methods for the study of human consciousness

PubMed Central

Olivares, Francisco A.; Vargas, Esteban; Fuentes, Claudio; Martínez-Pernía, David; Canales-Johnson, Andrés

2015-01-01

In the study of consciousness, neurophenomenology was originally established as a novel research program attempting to reconcile two apparently irreconcilable methodologies in psychology: qualitative and quantitative methods. Its potential relies on Francisco Varela’s idea of reciprocal constraints, in which first-person accounts and neurophysiological data mutually inform each other. However, since its first conceptualization, neurophenomenology has encountered methodological problems. These problems have emerged mainly because of the difficulty of obtaining and analyzing subjective reports in a systematic manner. However, more recently, several interview techniques for describing subjective accounts have been developed, collectively known as “second-person methods.” Second-person methods refer to interview techniques that solicit both verbal and non-verbal information from participants in order to obtain systematic and detailed subjective reports. Here, we examine the potential for employing second-person methodologies in the neurophenomenological study of consciousness and we propose three practical ideas for developing a second-person neurophenomenological method. Thus, we first describe second-person methodologies available in the literature for analyzing subjective reports, identifying specific constraints on the status of the first-, second- and third- person methods. Second, we analyze two experimental studies that explicitly incorporate second-person methods for traversing the “gap” between phenomenology and neuroscience. Third, we analyze the challenges that second-person accounts face in establishing an objective methodology for comparing results across different participants and interviewers: this is the “validation” problem. Finally, we synthesize the common aspects of the interview methods described above. In conclusion, our arguments emphasize that second-person methods represent a powerful approach for closing the gap between the experiential and the neurobiological levels of description in the study of human consciousness. PMID:26074839

Combined Orthodontic and Surgical Approach in the Correction of a Class III Skeletal Malocclusion with Mandibular Prognathism and Vertical Maxillary Excess Using Bimaxillary Osteotomy.

PubMed

Jose Cherackal, George; Thomas, Eapen; Prathap, Akhilesh

2013-01-01

For patients whose orthodontic problems are so severe that neither growth modification nor camouflage offers a solution, surgery to realign the jaws or reposition dentoalveolar segments is the only possible treatment. Surgery is not a substitute for orthodontics in these patients. Instead, it must be properly coordinated with orthodontics and other dental treatments to achieve good overall results. Dramatic progress in recent years has made it possible for combined surgical orthodontic treatment to be carried out successfully for patients with a severe dentofacial problem of any type. This case report provides an overview of the current treatment methodology in managing a combination of asymmetrical mandibular prognathism and vertical maxillary excess.

Problem solving using soft systems methodology.

PubMed

Land, L

This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.

Ductile failure X-prize.

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

Cox, James V.; Wellman, Gerald William; Emery, John M.

2011-09-01

Fracture or tearing of ductile metals is a pervasive engineering concern, yet accurate prediction of the critical conditions of fracture remains elusive. Sandia National Laboratories has been developing and implementing several new modeling methodologies to address problems in fracture, including both new physical models and new numerical schemes. The present study provides a double-blind quantitative assessment of several computational capabilities including tearing parameters embedded in a conventional finite element code, localization elements, extended finite elements (XFEM), and peridynamics. For this assessment, each of four teams reported blind predictions for three challenge problems spanning crack initiation and crack propagation. After predictionsmore » had been reported, the predictions were compared to experimentally observed behavior. The metal alloys for these three problems were aluminum alloy 2024-T3 and precipitation hardened stainless steel PH13-8Mo H950. The predictive accuracies of the various methods are demonstrated, and the potential sources of error are discussed.« less

Applied Swarm-based medicine: collecting decision trees for patterns of algorithms analysis.

PubMed

Panje, Cédric M; Glatzer, Markus; von Rappard, Joscha; Rothermundt, Christian; Hundsberger, Thomas; Zumstein, Valentin; Plasswilm, Ludwig; Putora, Paul Martin

2017-08-16

The objective consensus methodology has recently been applied in consensus finding in several studies on medical decision-making among clinical experts or guidelines. The main advantages of this method are an automated analysis and comparison of treatment algorithms of the participating centers which can be performed anonymously. Based on the experience from completed consensus analyses, the main steps for the successful implementation of the objective consensus methodology were identified and discussed among the main investigators. The following steps for the successful collection and conversion of decision trees were identified and defined in detail: problem definition, population selection, draft input collection, tree conversion, criteria adaptation, problem re-evaluation, results distribution and refinement, tree finalisation, and analysis. This manuscript provides information on the main steps for successful collection of decision trees and summarizes important aspects at each point of the analysis.

Risk Assessment to Underpin Food Regulatory Decisions: An Example of Public Health Nutritional Epidemiology

PubMed Central

Baines, Janis; Cunningham, Judy; Leemhuis, Christel; Hambridge, Tracy; Mackerras, Dorothy

2011-01-01

The approach used by food regulation agencies to examine the literature and forecast the impact of possible food regulations has many similar features to the approach used in nutritional epidemiological research. We outline the Risk Analysis Framework described by FAO/WHO, in which there is formal progression from identification of the nutrient or food chemical of interest, through to describing its effect on health and then assessing whether there is a risk to the population based on dietary exposure estimates. We then discuss some important considerations for the dietary modeling component of the Framework, including several methodological issues that also exist in research nutritional epidemiology. Finally, we give several case studies that illustrate how the different methodological components are used together to inform decisions about how to manage the regulatory problem. PMID:22254081

Recent archaeomagnetic studies in Slovakia: Comparison of methodological approaches

NASA Astrophysics Data System (ADS)

Kubišová, Lenka

2016-03-01

We review the recent archaeomagnetic studies carried out on the territory of Slovakia, focusing on the comparison of methodological approaches, discussing pros and cons of the individual applied methods from the perspective of our experience. The most widely used methods for the determination of intensity and direction of the archaeomegnetic field by demagnetisation of the sample material are the alternating field (AF) demagnetisation and the Thellier double heating method. These methods are used not only for archaeomagnetic studies but also help to solve some geological problems. The two methods were applied to samples collected recently at several sites of Slovakia, where archaeological prospection invoked by earthwork or reconstruction work of developing projects demanded archaeomagnetic dating. Then we discuss advantages and weaknesses of the investigated methods from different perspectives based on several examples and our recent experience.

Artistic image analysis using graph-based learning approaches.

PubMed

Carneiro, Gustavo

2013-08-01

We introduce a new methodology for the problem of artistic image analysis, which among other tasks, involves the automatic identification of visual classes present in an art work. In this paper, we advocate the idea that artistic image analysis must explore a graph that captures the network of artistic influences by computing the similarities in terms of appearance and manual annotation. One of the novelties of our methodology is the proposed formulation that is a principled way of combining these two similarities in a single graph. Using this graph, we show that an efficient random walk algorithm based on an inverted label propagation formulation produces more accurate annotation and retrieval results compared with the following baseline algorithms: bag of visual words, label propagation, matrix completion, and structural learning. We also show that the proposed approach leads to a more efficient inference and training procedures. This experiment is run on a database containing 988 artistic images (with 49 visual classification problems divided into a multiclass problem with 27 classes and 48 binary problems), where we show the inference and training running times, and quantitative comparisons with respect to several retrieval and annotation performance measures.

Problem reporting and tracking system: a systems engineering challenge

NASA Astrophysics Data System (ADS)

Cortez, Vasco; Lopez, Bernhard; Whyborn, Nicholas; Price, Roberto; Hernandez, Octavio; Gairing, Stefan; Barrios, Emilio; Alarcon, Hector

2016-08-01

The problem reporting and tracking system (PRTS) is the ALMA system to register operational problems, track unplanned corrective operational maintenance activities and follow the investigations of all problems or possible issues arisen in operation activities. After the PRTS implementation appeared several issues that finally produced a lack in the management of the investigations, problems to produce KPIs, loss of information, among others. In order to improve PRTS, we carried out a process to review the status of system, define a set of modifications and implement a solution; all according to the stakeholder requirements. In this work, we shall present the methodology applied to define a set of concrete actions at the basis of understanding the complexity of the problem, which finally got to improve the interactions between different subsystems and enhance the communication at different levels.

Evaluating a Web-Based Interface for Internet Telemedicine

NASA Technical Reports Server (NTRS)

Lathan, Corinna E.; Newman, Dava J.; Sebrechts, Marc M.; Doarn, Charles R.

1997-01-01

The objective is to introduce the usability engineering methodology, heuristic evaluation, to the design and development of a web-based telemedicine system. Using a set of usability criteria, or heuristics, one evaluator examined the Spacebridge to Russia web-site for usability problems. Thirty-four usability problems were found in this preliminary study and all were assigned a severity rating. The value of heuristic analysis in the iterative design of a system is shown because the problems can be fixed before deployment of a system and the problems are of a different nature than those found by actual users of the system. It was therefore determined that there is potential value of heuristic evaluation paired with user testing as a strategy for optimal system performance design.

What we know and don't know about mental health problems among immigrants in Norway.

PubMed

Abebe, Dawit Shawel; Lien, Lars; Hjelde, Karin Harsløf

2014-02-01

Mental health problems have been regarded as one of the main public health challenges of immigrants in several countries. Understanding and generating research-based knowledge on immigrant health problems is highly relevant for planning preventive interventions, as well as guiding social and policy actions. This review aims to map the available knowledge on immigrants' mental health status and its associated risk factors in Norway. The reviewed literature about mental health problems among immigrant populations in Norway was found through databases, such as PUBMED, EMBASE, PsychINFO and MEDLINE. About 41 peer-reviewed original articles published since 1990s were included. In the majority of the studies, the immigrant populations, specifically adult immigrants from low and middle income countries, have been found with a higher degree of mental health problems compared to Norwegians and the general population. Increased risk for mental illness is primarily linked to a higher risk for acculturative stress, poor social support, deprived socioeconomic conditions, multiple negative life events, experiences of discrimination and traumatic pre-migration experiences. However, research in this field has been confronted by a number of gaps and methodological challenges. The available knowledge indicates a need for preventive interventions. Correspondingly, it strongly recommends a comprehensive research program that addresses gaps and methodological challenges.

Issue Brief #2: Metrics for Improving Cost Accountability (Hint: Not More Detailed Cost Accounting...)

ERIC Educational Resources Information Center

Delta Project on Postsecondary Education Costs, Productivity and Accountability, 2009

2009-01-01

Most fiscal reporting focuses on revenues (whether or not they go to core purposes), tuition and fees, and financial aid. "How" the money is spent is something that remains shrouded in too much mystery. Several national efforts to address this problem have largely come to naught--probably because those common methodologies are simultaneously not…

Problem Solving Approaches in Mathematics Education as a Product of Japanese Lesson Study

ERIC Educational Resources Information Center

Isoda, Masami

2011-01-01

What is the product of Lesson Study? Lesson Study is a scientific activity for teachers based on the methodology introduced in the 1880s. In Japan, research topics for Lesson Study are usually shared through the regular revisions of the curriculum and the research movement of several societies. As a result of teachers' efforts to overcome…

Intercomparison of magnetic field measurements near MV/LV transformer substations: methodological planning and results.

PubMed

Violanti, S; Fraschetta, M; Adda, S; Caputo, E

2009-12-01

Within the framework of Environmental Agencies system's activities, coordinated by ISPRA (superior institute for environmental protection and research), a comparison among measurements was designed and accomplished, in order to go into depth on the matter of measurement problems and to evaluate magnetic field at power frequencies. These measurements have been taken near medium voltage /low voltage transformer substation. This project was developed with the contribution of several experts who belong to different Regional Agencies. In three of these regions, substations having specific international standard characteristics were chosen; then a measurement and data analysis protocol was arranged. Data analysis showed a good level of coherence among results obtained by different laboratories. However, a range of problems emerged, either during the protocol predisposition and definition of the data analysis procedure or during the execution of measures and data reprocessing, because of the spatial and temporal variability of magnetic field. These problems represent elements of particular interest in determining a correct measurement methodology, whose purpose is the comparison with limits of exposure, attention values and quality targets.

A mini-review of TAT-MyoD fused proteins: state of the art and problems to solve.

PubMed

Patruno, Marco; Melotti, Luca; Gomiero, Chiara; Sacchetto, Roberta; Topel, Ohad; Martinello, Tiziana

2017-12-05

The transcriptional activator TAT is a small peptide essential for viral replication and possesses the property of entering the cells from the extracellular milieu, acting as a membrane shuttle. In order to safely differentiate cells an innovative methodology, based on the fusion of transcription factors and the TAT sequence, is discussed in this short review. In several studies, it has been demonstrated that TAT protein can be observed in the cell nucleus after few hours from the inoculation although its way of action is not fully understood. However, further studies will be necessary to develop this methodology for clinical purposes.

Statistics and Informatics in Space Astrophysics

NASA Astrophysics Data System (ADS)

Feigelson, E.

2017-12-01

The interest in statistical and computational methodology has seen rapid growth in space-based astrophysics, parallel to the growth seen in Earth remote sensing. There is widespread agreement that scientific interpretation of the cosmic microwave background, discovery of exoplanets, and classifying multiwavelength surveys is too complex to be accomplished with traditional techniques. NASA operates several well-functioning Science Archive Research Centers providing 0.5 PBy datasets to the research community. These databases are integrated with full-text journal articles in the NASA Astrophysics Data System (200K pageviews/day). Data products use interoperable formats and protocols established by the International Virtual Observatory Alliance. NASA supercomputers also support complex astrophysical models of systems such as accretion disks and planet formation. Academic researcher interest in methodology has significantly grown in areas such as Bayesian inference and machine learning, and statistical research is underway to treat problems such as irregularly spaced time series and astrophysical model uncertainties. Several scholarly societies have created interest groups in astrostatistics and astroinformatics. Improvements are needed on several fronts. Community education in advanced methodology is not sufficiently rapid to meet the research needs. Statistical procedures within NASA science analysis software are sometimes not optimal, and pipeline development may not use modern software engineering techniques. NASA offers few grant opportunities supporting research in astroinformatics and astrostatistics.

Combined Orthodontic and Surgical Approach in the Correction of a Class III Skeletal Malocclusion with Mandibular Prognathism and Vertical Maxillary Excess Using Bimaxillary Osteotomy

PubMed Central

Jose Cherackal, George; Thomas, Eapen; Prathap, Akhilesh

2013-01-01

For patients whose orthodontic problems are so severe that neither growth modification nor camouflage offers a solution, surgery to realign the jaws or reposition dentoalveolar segments is the only possible treatment. Surgery is not a substitute for orthodontics in these patients. Instead, it must be properly coordinated with orthodontics and other dental treatments to achieve good overall results. Dramatic progress in recent years has made it possible for combined surgical orthodontic treatment to be carried out successfully for patients with a severe dentofacial problem of any type. This case report provides an overview of the current treatment methodology in managing a combination of asymmetrical mandibular prognathism and vertical maxillary excess. PMID:24455321

Self-Calibration and Optimal Response in Intelligent Sensors Design Based on Artificial Neural Networks

PubMed Central

Rivera, José; Carrillo, Mariano; Chacón, Mario; Herrera, Gilberto; Bojorquez, Gilberto

2007-01-01

The development of smart sensors involves the design of reconfigurable systems capable of working with different input sensors. Reconfigurable systems ideally should spend the least possible amount of time in their calibration. An autocalibration algorithm for intelligent sensors should be able to fix major problems such as offset, variation of gain and lack of linearity, as accurately as possible. This paper describes a new autocalibration methodology for nonlinear intelligent sensors based on artificial neural networks, ANN. The methodology involves analysis of several network topologies and training algorithms. The proposed method was compared against the piecewise and polynomial linearization methods. Method comparison was achieved using different number of calibration points, and several nonlinear levels of the input signal. This paper also shows that the proposed method turned out to have a better overall accuracy than the other two methods. Besides, experimentation results and analysis of the complete study, the paper describes the implementation of the ANN in a microcontroller unit, MCU. In order to illustrate the method capability to build autocalibration and reconfigurable systems, a temperature measurement system was designed and tested. The proposed method is an improvement over the classic autocalibration methodologies, because it impacts on the design process of intelligent sensors, autocalibration methodologies and their associated factors, like time and cost.

The mathematical statement for the solving of the problem of N-version software system design

NASA Astrophysics Data System (ADS)

Kovalev, I. V.; Kovalev, D. I.; Zelenkov, P. V.; Voroshilova, A. A.

2015-10-01

The N-version programming, as a methodology of the fault-tolerant software systems design, allows successful solving of the mentioned tasks. The use of N-version programming approach turns out to be effective, since the system is constructed out of several parallel executed versions of some software module. Those versions are written to meet the same specification but by different programmers. The problem of developing an optimal structure of N-version software system presents a kind of very complex optimization problem. This causes the use of deterministic optimization methods inappropriate for solving the stated problem. In this view, exploiting heuristic strategies looks more rational. In the field of pseudo-Boolean optimization theory, the so called method of varied probabilities (MVP) has been developed to solve problems with a large dimensionality.

A combinatorial framework to quantify peak/pit asymmetries in complex dynamics.

PubMed

Hasson, Uri; Iacovacci, Jacopo; Davis, Ben; Flanagan, Ryan; Tagliazucchi, Enzo; Laufs, Helmut; Lacasa, Lucas

2018-02-23

We explore a combinatorial framework which efficiently quantifies the asymmetries between minima and maxima in local fluctuations of time series. We first showcase its performance by applying it to a battery of synthetic cases. We find rigorous results on some canonical dynamical models (stochastic processes with and without correlations, chaotic processes) complemented by extensive numerical simulations for a range of processes which indicate that the methodology correctly distinguishes different complex dynamics and outperforms state of the art metrics in several cases. Subsequently, we apply this methodology to real-world problems emerging across several disciplines including cases in neurobiology, finance and climate science. We conclude that differences between the statistics of local maxima and local minima in time series are highly informative of the complex underlying dynamics and a graph-theoretic extraction procedure allows to use these features for statistical learning purposes.

The Davey-Stewartson Equation on the Half-Plane

NASA Astrophysics Data System (ADS)

Fokas, A. S.

2009-08-01

The Davey-Stewartson (DS) equation is a nonlinear integrable evolution equation in two spatial dimensions. It provides a multidimensional generalisation of the celebrated nonlinear Schrödinger (NLS) equation and it appears in several physical situations. The implementation of the Inverse Scattering Transform (IST) to the solution of the initial-value problem of the NLS was presented in 1972, whereas the analogous problem for the DS equation was solved in 1983. These results are based on the formulation and solution of certain classical problems in complex analysis, namely of a Riemann Hilbert problem (RH) and of either a d-bar or a non-local RH problem respectively. A method for solving the mathematically more complicated but physically more relevant case of boundary-value problems for evolution equations in one spatial dimension, like the NLS, was finally presented in 1997, after interjecting several novel ideas to the panoply of the IST methodology. Here, this method is further extended so that it can be applied to evolution equations in two spatial dimensions, like the DS equation. This novel extension involves several new steps, including the formulation of a d-bar problem for a sectionally non-analytic function, i.e. for a function which has different non-analytic representations in different domains of the complex plane. This, in addition to the computation of a d-bar derivative, also requires the computation of the relevant jumps across the different domains. This latter step has certain similarities (but is more complicated) with the corresponding step for those initial-value problems in two dimensions which can be solved via a non-local RH problem, like KPI.

A Selective Review of Group Selection in High-Dimensional Models

PubMed Central

Huang, Jian; Breheny, Patrick; Ma, Shuangge

2013-01-01

Grouping structures arise naturally in many statistical modeling problems. Several methods have been proposed for variable selection that respect grouping structure in variables. Examples include the group LASSO and several concave group selection methods. In this article, we give a selective review of group selection concerning methodological developments, theoretical properties and computational algorithms. We pay particular attention to group selection methods involving concave penalties. We address both group selection and bi-level selection methods. We describe several applications of these methods in nonparametric additive models, semiparametric regression, seemingly unrelated regressions, genomic data analysis and genome wide association studies. We also highlight some issues that require further study. PMID:24174707

Molecular engineering of colloidal liquid crystals using DNA origami

NASA Astrophysics Data System (ADS)

Siavashpouri, Mahsa; Wachauf, Christian; Zakhary, Mark; Praetorius, Florian; Dietz, Hendrik; Dogic, Zvonimir

Understanding the microscopic origin of cholesteric phase remains a foundational, yet unresolved problem in the field of liquid crystals. Lack of experimental model system that allows for the systematic control of the microscopic chiral structure makes it difficult to investigate this problem for several years. Here, using DNA origami technology, we systematically vary the chirality of the colloidal particles with molecular precision and establish a quantitative relationship between the microscopic structure of particles and the macroscopic cholesteric pitch. Our study presents a new methodology for predicting bulk behavior of diverse phases based on the microscopic architectures of the constituent molecules.

Applications of decision analysis and related techniques to industrial engineering problems at KSC

NASA Technical Reports Server (NTRS)

Evans, Gerald W.

1995-01-01

This report provides: (1) a discussion of the origination of decision analysis problems (well-structured problems) from ill-structured problems; (2) a review of the various methodologies and software packages for decision analysis and related problem areas; (3) a discussion of how the characteristics of a decision analysis problem affect the choice of modeling methodologies, thus providing a guide as to when to choose a particular methodology; and (4) examples of applications of decision analysis to particular problems encountered by the IE Group at KSC. With respect to the specific applications at KSC, particular emphasis is placed on the use of the Demos software package (Lumina Decision Systems, 1993).

Clinical relevance in anesthesia journals.

PubMed

Lauritsen, Jakob; Møller, Ann M

2006-04-01

The purpose of this review is to present the latest knowledge and research on the definition and distribution of clinically relevant articles in anesthesia journals. It will also discuss the importance of the chosen methodology and outcome of articles. In the last few years, more attention has been paid to evidence-based medicine in anesthesia. Several articles on the subject have focused on the need to base clinical decisions on sound research employing both methodological rigor and clinically relevant outcomes. The number of systematic reviews in anesthesia literature is increasing as well as the focus on diminishing the number of surrogate outcomes. It has been shown that the impact factor is not a valid measure of establishing the level of clinical relevance to a journal. This review presents definitions of clinically relevant anesthesia articles. A clinically relevant article employs both methodological rigor and a clinically relevant outcome. The terms methodological rigor and clinical outcomes are fully discussed in the review as well as problems with journal impact factors.

Conceptual design and multidisciplinary optimization of in-plane morphing wing structures

NASA Astrophysics Data System (ADS)

Inoyama, Daisaku; Sanders, Brian P.; Joo, James J.

2006-03-01

In this paper, the topology optimization methodology for the synthesis of distributed actuation system with specific applications to the morphing air vehicle is discussed. The main emphasis is placed on the topology optimization problem formulations and the development of computational modeling concepts. For demonstration purposes, the inplane morphing wing model is presented. The analysis model is developed to meet several important criteria: It must allow large rigid-body displacements, as well as variation in planform area, with minimum strain on structural members while retaining acceptable numerical stability for finite element analysis. Preliminary work has indicated that addressed modeling concept meets the criteria and may be suitable for the purpose. Topology optimization is performed on the ground structure based on this modeling concept with design variables that control the system configuration. In other words, states of each element in the model are design variables and they are to be determined through optimization process. In effect, the optimization process assigns morphing members as 'soft' elements, non-morphing load-bearing members as 'stiff' elements, and non-existent members as 'voids.' In addition, the optimization process determines the location and relative force intensities of distributed actuators, which is represented computationally as equal and opposite nodal forces with soft axial stiffness. Several different optimization problem formulations are investigated to understand their potential benefits in solution quality, as well as meaningfulness of formulation itself. Sample in-plane morphing problems are solved to demonstrate the potential capability of the methodology introduced in this paper.

General Methodology for Designing Spacecraft Trajectories

NASA Technical Reports Server (NTRS)

Condon, Gerald; Ocampo, Cesar; Mathur, Ravishankar; Morcos, Fady; Senent, Juan; Williams, Jacob; Davis, Elizabeth C.

2012-01-01

A methodology for designing spacecraft trajectories in any gravitational environment within the solar system has been developed. The methodology facilitates modeling and optimization for problems ranging from that of a single spacecraft orbiting a single celestial body to that of a mission involving multiple spacecraft and multiple propulsion systems operating in gravitational fields of multiple celestial bodies. The methodology consolidates almost all spacecraft trajectory design and optimization problems into a single conceptual framework requiring solution of either a system of nonlinear equations or a parameter-optimization problem with equality and/or inequality constraints.

Philosophy of clinical psychopharmacology.

PubMed

Aragona, Massimiliano

2013-03-01

The renewal of the philosophical debate in psychiatry is one exciting news of recent years. However, its use in psychopharmacology may be problematic, ranging from self-confinement into the realm of values (which leaves the evidence-based domain unchallenged) to complete rejection of scientific evidence. In this paper philosophy is conceived as a conceptual audit of clinical psychopharmacology. Its function is to criticise the epistemological and methodological problems of current neopositivist, ingenuously realist and evidence-servant psychiatry from within the scientific stance and with the aim of aiding psychopharmacologists in practicing a more self-aware, critical and possibly useful clinical practice. Three examples are discussed to suggest that psychopharmacological practice needs conceptual clarification. At the diagnostic level it is shown that the crisis of the current diagnostic system and the problem of comorbidity strongly influence psychopharmacological results, new conceptualizations more respondent to the psychopharmacological requirements being needed. Heterogeneity of research samples, lack of specificity of psychotropic drugs, difficult generalizability of results, need of a phenomenological study of drug-induced psychopathological changes are discussed herein. At the methodological level the merits and limits of evidence-based practice are considered, arguing that clinicians should know the best available evidence but that guidelines should not be constrictive (due to several methodological biases and rhetorical tricks of which the clinician should be aware, sometimes respondent to extra-scientific, economical requests). At the epistemological level it is shown that the clinical stance is shaped by implicit philosophical beliefs about the mind/body problem (reductionism, dualism, interactionism, pragmatism), and that philosophy can aid physicians to be more aware of their beliefs in order to choose the most useful view and to practice coherently. In conclusion, psychopharmacologists already use methodological audit (e.g. statistical audit); similarly, conceptual clarification is needed in both research planning/evaluation and everyday psychopharmacological practice.

Decision-problem state analysis methodology

NASA Technical Reports Server (NTRS)

Dieterly, D. L.

1980-01-01

A methodology for analyzing a decision-problem state is presented. The methodology is based on the analysis of an incident in terms of the set of decision-problem conditions encountered. By decomposing the events that preceded an unwanted outcome, such as an accident, into the set of decision-problem conditions that were resolved, a more comprehensive understanding is possible. All human-error accidents are not caused by faulty decision-problem resolutions, but it appears to be one of the major areas of accidents cited in the literature. A three-phase methodology is presented which accommodates a wide spectrum of events. It allows for a systems content analysis of the available data to establish: (1) the resolutions made, (2) alternatives not considered, (3) resolutions missed, and (4) possible conditions not considered. The product is a map of the decision-problem conditions that were encountered as well as a projected, assumed set of conditions that should have been considered. The application of this methodology introduces a systematic approach to decomposing the events that transpired prior to the accident. The initial emphasis is on decision and problem resolution. The technique allows for a standardized method of accident into a scenario which may used for review or the development of a training simulation.

Topology synthesis and size optimization of morphing wing structures

NASA Astrophysics Data System (ADS)

Inoyama, Daisaku

This research demonstrates a novel topology and size optimization methodology for synthesis of distributed actuation systems with specific applications to morphing air vehicle structures. The main emphasis is placed on the topology and size optimization problem formulations and the development of computational modeling concepts. The analysis model is developed to meet several important criteria: It must allow a rigid-body displacement, as well as a variation in planform area, with minimum strain on structural members while retaining acceptable numerical stability for finite element analysis. Topology optimization is performed on a semi-ground structure with design variables that control the system configuration. In effect, the optimization process assigns morphing members as "soft" elements, non-morphing load-bearing members as "stiff' elements, and non-existent members as "voids." The optimization process also determines the optimum actuator placement, where each actuator is represented computationally by equal and opposite nodal forces with soft axial stiffness. In addition, the configuration of attachments that connect the morphing structure to a non-morphing structure is determined simultaneously. Several different optimization problem formulations are investigated to understand their potential benefits in solution quality, as well as meaningfulness of the formulations. Extensions and enhancements to the initial concept and problem formulations are made to accommodate multiple-configuration definitions. In addition, the principal issues on the external-load dependency and the reversibility of a design, as well as the appropriate selection of a reference configuration, are addressed in the research. The methodology to control actuator distributions and concentrations is also discussed. Finally, the strategy to transfer the topology solution to the sizing optimization is developed and cross-sectional areas of existent structural members are optimized under applied aerodynamic loads. That is, the optimization process is implemented in sequential order: The actuation system layout is first determined through multi-disciplinary topology optimization process, and then the thickness or cross-sectional area of each existent member is optimized under given constraints and boundary conditions. Sample problems are solved to demonstrate the potential capabilities of the presented methodology. The research demonstrates an innovative structural design procedure from a computational perspective and opens new insights into the potential design requirements and characteristics of morphing structures.

Mining data from hemodynamic simulations for generating prediction and explanation models.

PubMed

Bosnić, Zoran; Vračar, Petar; Radović, Milos D; Devedžić, Goran; Filipović, Nenad D; Kononenko, Igor

2012-03-01

One of the most common causes of human death is stroke, which can be caused by carotid bifurcation stenosis. In our work, we aim at proposing a prototype of a medical expert system that could significantly aid medical experts to detect hemodynamic abnormalities (increased artery wall shear stress). Based on the acquired simulated data, we apply several methodologies for1) predicting magnitudes and locations of maximum wall shear stress in the artery, 2) estimating reliability of computed predictions, and 3) providing user-friendly explanation of the model's decision. The obtained results indicate that the evaluated methodologies can provide a useful tool for the given problem domain. © 2012 IEEE

Effects of Caffeine and Warrior Stress on Behavioral : An Animal Model

DTIC Science & Technology

2016-03-14

contributes invaluably to ethical and humane research. A special thank you to Erin Barry for providing statistical expertise and methodological support...of behavioral health in rats. Several ethical and logistical issues prevent the use of humans in true controlled experiments that manipulate stress...play in the development or maintenance of behavioral problems. There are ethical issues associated with exposing humans to high caffeine doses and

Homeless Mentally Ill: Problems and Options in Estimating Numbers and Trends. Report to the Chairman, Committee on Labor and Human Resources, U.S. Senate.

ERIC Educational Resources Information Center

General Accounting Office, Washington, DC. Program Evaluation and Methodology Div.

In response to a request by the United States Senate Committee on Labor and Human Resources, the General Accounting Office (GAO) examined the methodological soundness of current population estimates of the number of homeless chronically mentally ill persons, and proposed several options for estimating the size of this population. The GAO reviewed…

A hybrid approach to survival model building using integration of clinical and molecular information in censored data.

PubMed

Choi, Ickwon; Kattan, Michael W; Wells, Brian J; Yu, Changhong

2012-01-01

In medical society, the prognostic models, which use clinicopathologic features and predict prognosis after a certain treatment, have been externally validated and used in practice. In recent years, most research has focused on high dimensional genomic data and small sample sizes. Since clinically similar but molecularly heterogeneous tumors may produce different clinical outcomes, the combination of clinical and genomic information, which may be complementary, is crucial to improve the quality of prognostic predictions. However, there is a lack of an integrating scheme for clinic-genomic models due to the P ≥ N problem, in particular, for a parsimonious model. We propose a methodology to build a reduced yet accurate integrative model using a hybrid approach based on the Cox regression model, which uses several dimension reduction techniques, L₂ penalized maximum likelihood estimation (PMLE), and resampling methods to tackle the problem. The predictive accuracy of the modeling approach is assessed by several metrics via an independent and thorough scheme to compare competing methods. In breast cancer data studies on a metastasis and death event, we show that the proposed methodology can improve prediction accuracy and build a final model with a hybrid signature that is parsimonious when integrating both types of variables.

Applications of fuzzy theories to multi-objective system optimization

NASA Technical Reports Server (NTRS)

Rao, S. S.; Dhingra, A. K.

1991-01-01

Most of the computer aided design techniques developed so far deal with the optimization of a single objective function over the feasible design space. However, there often exist several engineering design problems which require a simultaneous consideration of several objective functions. This work presents several techniques of multiobjective optimization. In addition, a new formulation, based on fuzzy theories, is also introduced for the solution of multiobjective system optimization problems. The fuzzy formulation is useful in dealing with systems which are described imprecisely using fuzzy terms such as, 'sufficiently large', 'very strong', or 'satisfactory'. The proposed theory translates the imprecise linguistic statements and multiple objectives into equivalent crisp mathematical statements using fuzzy logic. The effectiveness of all the methodologies and theories presented is illustrated by formulating and solving two different engineering design problems. The first one involves the flight trajectory optimization and the main rotor design of helicopters. The second one is concerned with the integrated kinematic-dynamic synthesis of planar mechanisms. The use and effectiveness of nonlinear membership functions in fuzzy formulation is also demonstrated. The numerical results indicate that the fuzzy formulation could yield results which are qualitatively different from those provided by the crisp formulation. It is felt that the fuzzy formulation will handle real life design problems on a more rational basis.

Analysis of individual risk belief structures

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

Tonn, B.E.; Travis, C.B.; Arrowood, L.

An interactive computer program developed at Oak Ridge National Laboratory is presented as a methodology to model individualized belief structures. The logic and general strategy of the model is presented for two risk topics: AIDs and toxic waste. Subjects identified desirable and undesirable consequences for each topic and formulated an associative rule linking topic and consequence in either a causal or correlational framework. Likelihood estimates, generated by subjects in several formats (probability, odds statements, etc.), constituted one outcome measure. Additionally, source of belief (personal experience, news media, etc.) and perceived personal and societal impact are reviewed. Briefly, subjects believe thatmore » AIDs causes significant emotional problems, and to a lesser degree, physical health problems whereas toxic waste causes significant environmental problems.« less

Monitoring the Impact of Solution Concepts within a Given Problematic

NASA Astrophysics Data System (ADS)

Cavallucci, Denis; Rousselot, François; Zanni, Cecilia

It is acknowledged that one of the most critical issues facing today’s organizations concerns the substantial leaps required to methodologically structure innovation. Among other published work, some suggest that a complete rethinking of current practices is required. In this article, we propose a methodology aiming at providing controlled R&D choices based on a monitoring of the impact Solution Concepts provoke on a problematic situation. Initially this problematic situation is modeled in a graph form, namely a Problem Graph. It has the objective to assists R&D managers when choosing which activities to support and bring them concrete arguments to defend their choices. We postulate that by improving the robustness of such approaches we help deciders to switch from intuitive decisions (mostly built upon their past experiences, fear regarding risks, and awareness of the company’s level of acceptance of novelties) to thoroughly constructed inventive problem solving strategies. Our approach will be discussed using a computer application that illustrates our hypothesis after being tested in several industrial applications.

Ergonomic initiatives at Inmetro: measuring occupational health and safety.

PubMed

Drucker, L; Amaral, M; Carvalheira, C

2012-01-01

This work studies biomechanical hazards to which the workforce of Instituto Nacional de Metrologia, Qualidade e Tecnologia Industrial (Inmetro) is exposed. It suggests a model for ergonomic evaluation of work, based on the concepts of resilience engineering which take into consideration the institute's ability to manage risk and deal with its consequences. Methodology includes the stages of identification, inventory, analysis, and risk management. Diagnosis of the workplace uses as parameters the minimal criteria stated in Brazilian legislation. The approach has several prospectives and encompasses the points of view of public management, safety engineering, physical therapy and ergonomics-oriented design. The suggested solution integrates all aspects of the problem: biological, psychological, sociological and organizational. Results obtained from a pilot Project allow to build a significant sample of Inmetro's workforce, identifying problems and validating the methodology employed as a tool to be applied to the whole institution. Finally, this work intends to draw risk maps and support goals and methods based on resiliency engineering to assess environmental and ergonomic risk management.

A methodology model for quality management in a general hospital.

PubMed

Stern, Z; Naveh, E

1997-01-01

A reappraisal is made of the relevance of industrial modes of quality management to the issues of medical care. Analysis of the nature of medical care, which differentiates it from the supplier-client relationships of industry, presents the main intrinsic characteristics, which create problems in application of the industrial quality management approaches to medical care. Several examples are the complexity of the relationship between the medical action and the result obtained, the client's nonacceptance of economic profitability as a value in his medical care, and customer satisfaction biased by variable standards of knowledge. The real problems unique to hospitals are addressed, and a methodology model for their quality management is offered. Included is a sample of indicator vectors, measurements of quality care, cost of medical care, quality of service, and human resources. These are based on the trilogy of planning quality, quality control, and improving quality. The conclusions confirm the inadequacy of industrial quality management approaches for medical institutions and recommend investment in formulation of appropriate concepts.

Utilization of integrated Michaelis-Menten equations for enzyme inhibition diagnosis and determination of kinetic constants using Solver supplement of Microsoft Office Excel.

PubMed

Bezerra, Rui M F; Fraga, Irene; Dias, Albino A

2013-01-01

Enzyme kinetic parameters are usually determined from initial rates nevertheless, laboratory instruments only measure substrate or product concentration versus reaction time (progress curves). To overcome this problem we present a methodology which uses integrated models based on Michaelis-Menten equation. The most severe practical limitation of progress curve analysis occurs when the enzyme shows a loss of activity under the chosen assay conditions. To avoid this problem it is possible to work with the same experimental points utilized for initial rates determination. This methodology is illustrated by the use of integrated kinetic equations with the well-known reaction catalyzed by alkaline phosphatase enzyme. In this work nonlinear regression was performed with the Solver supplement (Microsoft Office Excel). It is easy to work with and track graphically the convergence of SSE (sum of square errors). The diagnosis of enzyme inhibition was performed according to Akaike information criterion. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Soft Systems Methodology and Problem Framing: Development of an Environmental Problem Solving Model Respecting a New Emergent Reflexive Paradigm.

ERIC Educational Resources Information Center

Gauthier, Benoit; And Others

1997-01-01

Identifies the more representative problem-solving models in environmental education. Suggests the addition of a strategy for defining a problem situation using Soft Systems Methodology to environmental education activities explicitly designed for the development of critical thinking. Contains 45 references. (JRH)

Towards the unification of inference structures in medical diagnostic tasks.

PubMed

Mira, J; Rives, J; Delgado, A E; Martínez, R

1998-01-01

The central purpose of artificial intelligence applied to medicine is to develop models for diagnosis and therapy planning at the knowledge level, in the Newell sense, and software environments to facilitate the reduction of these models to the symbol level. The usual methodology (KADS, Common-KADS, GAMES, HELIOS, Protégé, etc) has been to develop libraries of generic tasks and reusable problem-solving methods with explicit ontologies. The principal problem which clinicians have with these methodological developments concerns the diversity and complexity of new terms whose meaning is not sufficiently clear, precise, unambiguous and consensual for them to be accessible in the daily clinical environment. As a contribution to the solution of this problem, we develop in this article the conjecture that one inference structure is enough to describe the set of analysis tasks associated with medical diagnoses. To this end, we first propose a modification of the systematic diagnostic inference scheme to obtain an analysis generic task and then compare it with the monitoring and the heuristic classification task inference schemes using as comparison criteria the compatibility of domain roles (data structures), the similarity in the inferences, and the commonality in the set of assumptions which underlie the functionally equivalent models. The equivalences proposed are illustrated with several examples. Note that though our ongoing work aims to simplify the methodology and to increase the precision of the terms used, the proposal presented here should be viewed more in the nature of a conjecture.

C-Based Design Methodology and Topological Change for an Indian Agricultural Tractor Component

NASA Astrophysics Data System (ADS)

Matta, Anil Kumar; Raju, D. Ranga; Suman, K. N. S.; Kranthi, A. S.

2018-06-01

The failure of tractor components and their replacement has now become very common in India because of re-cycling, re-sale, and duplication. To over come the problem of failure we propose a design methodology for topological change co-simulating with software's. In the proposed Design methodology, the designer checks Paxial, Pcr, Pfailue, τ by hand calculations, from which refined topological changes of R.S.Arm are formed. We explained several techniques employed in the component for reduction, removal of rib material to change center of gravity and centroid point by using system C for mixed level simulation and faster topological changes. The design process in system C can be compiled and executed with software, TURBO C7. The modified component is developed in proE and analyzed in ANSYS. The topologically changed component with slot 120 × 4.75 × 32.5 mm at the center showed greater effectiveness than the original component.

Formal verification of human-automation interaction

NASA Technical Reports Server (NTRS)

Degani, Asaf; Heymann, Michael

2002-01-01

This paper discusses a formal and rigorous approach to the analysis of operator interaction with machines. It addresses the acute problem of detecting design errors in human-machine interaction and focuses on verifying the correctness of the interaction in complex and automated control systems. The paper describes a systematic methodology for evaluating whether the interface provides the necessary information about the machine to enable the operator to perform a specified task successfully and unambiguously. It also addresses the adequacy of information provided to the user via training material (e.g., user manual) about the machine's behavior. The essentials of the methodology, which can be automated and applied to the verification of large systems, are illustrated by several examples and through a case study of pilot interaction with an autopilot aboard a modern commercial aircraft. The expected application of this methodology is an augmentation and enhancement, by formal verification, of human-automation interfaces.

C-Based Design Methodology and Topological Change for an Indian Agricultural Tractor Component

NASA Astrophysics Data System (ADS)

Matta, Anil Kumar; Raju, D. Ranga; Suman, K. N. S.; Kranthi, A. S.

2018-02-01

The failure of tractor components and their replacement has now become very common in India because of re-cycling, re-sale, and duplication. To over come the problem of failure we propose a design methodology for topological change co-simulating with software's. In the proposed Design methodology, the designer checks Paxial, Pcr, Pfailue, τ by hand calculations, from which refined topological changes of R.S.Arm are formed. We explained several techniques employed in the component for reduction, removal of rib material to change center of gravity and centroid point by using system C for mixed level simulation and faster topological changes. The design process in system C can be compiled and executed with software, TURBO C7. The modified component is developed in proE and analyzed in ANSYS. The topologically changed component with slot 120 × 4.75 × 32.5 mm at the center showed greater effectiveness than the original component.

Multichannel myopic deconvolution in underwater acoustic channels via low-rank recovery

PubMed Central

Tian, Ning; Byun, Sung-Hoon; Sabra, Karim; Romberg, Justin

2017-01-01

This paper presents a technique for solving the multichannel blind deconvolution problem. The authors observe the convolution of a single (unknown) source with K different (unknown) channel responses; from these channel outputs, the authors want to estimate both the source and the channel responses. The authors show how this classical signal processing problem can be viewed as solving a system of bilinear equations, and in turn can be recast as recovering a rank-1 matrix from a set of linear observations. Results of prior studies in the area of low-rank matrix recovery have identified effective convex relaxations for problems of this type and efficient, scalable heuristic solvers that enable these techniques to work with thousands of unknown variables. The authors show how a priori information about the channels can be used to build a linear model for the channels, which in turn makes solving these systems of equations well-posed. This study demonstrates the robustness of this methodology to measurement noises and parametrization errors of the channel impulse responses with several stylized and shallow water acoustic channel simulations. The performance of this methodology is also verified experimentally using shipping noise recorded on short bottom-mounted vertical line arrays. PMID:28599565

Cause-and-effect analysis of risk management files to assess patient care in the emergency department.

PubMed

White, Andrew A; Wright, Seth W; Blanco, Roberto; Lemonds, Brent; Sisco, Janice; Bledsoe, Sandy; Irwin, Cindy; Isenhour, Jennifer; Pichert, James W

2004-10-01

Identifying the etiologies of adverse outcomes is an important first step in improving patient safety and reducing malpractice risks. However, relatively little is known about the causes of emergency department-related adverse outcomes. The objective was to describe a method for identification of common causes of adverse outcomes in an emergency department. This methodology potentially can suggest ways to improve care and might provide a model for identification of factors associated with adverse outcomes. This was a retrospective analysis of 74 consecutive files opened by a malpractice insurer between 1995 and 2000. Each risk-management file was analyzed to identify potential causes of adverse outcomes. The main outcomes were rater-assigned codes for alleged problems with care (e.g., failures of communication or problems related to diagnosis). About 50% of cases were related to injuries or abdominal complaints. A contributing cause was found in 92% of cases, and most had more than one contributing cause. The most frequent contributing categories included failure to diagnose (45%), supervision problems (31%), communication problems (30%), patient behavior (24%), administrative problems (20%), and documentation (20%). Specific relating factors within these categories, such as lack of timely resident supervision and failure to follow policies and procedures, were identified. This project documented that an aggregate analysis of risk-management files has the potential to identify shared causes related to real or perceived adverse outcomes. Several potentially correctable systems problems were identified using this methodology. These simple, descriptive management tools may be useful in identifying issues for problem solving and can be easily learned by physicians and managers.

Soft Computing Methods for Disulfide Connectivity Prediction.

PubMed

Márquez-Chamorro, Alfonso E; Aguilar-Ruiz, Jesús S

2015-01-01

The problem of protein structure prediction (PSP) is one of the main challenges in structural bioinformatics. To tackle this problem, PSP can be divided into several subproblems. One of these subproblems is the prediction of disulfide bonds. The disulfide connectivity prediction problem consists in identifying which nonadjacent cysteines would be cross-linked from all possible candidates. Determining the disulfide bond connectivity between the cysteines of a protein is desirable as a previous step of the 3D PSP, as the protein conformational search space is highly reduced. The most representative soft computing approaches for the disulfide bonds connectivity prediction problem of the last decade are summarized in this paper. Certain aspects, such as the different methodologies based on soft computing approaches (artificial neural network or support vector machine) or features of the algorithms, are used for the classification of these methods.

Alterations to Functional Analysis Methodology to Clarify the Functions of Low Rate, High Intensity Problem Behavior

PubMed Central

Davis, Barbara J; Schmidt, Jonathan; Bowman, Lynn G; Boelter, Eric W

2012-01-01

Current research provides few suggestions for modifications to functional analysis procedures to accommodate low rate, high intensity problem behavior. This study examined the results of the extended duration functional analysis procedures of Kahng, Abt, and Schonbachler (2001) with six children admitted to an inpatient hospital for the treatment of severe problem behavior. Results of initial functional analyses (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) were inconclusive for all children because of low levels of responding. The altered functional analyses, which changed multiple variables including the duration of the functional analysis (i.e., 6 or 7 hrs), yielded clear behavioral functions for all six participants. These results add additional support for the utility of an altered analysis of low rate, high intensity problem behavior when standard functional analyses do not yield differentiated results. PMID:23326628

Alterations to functional analysis methodology to clarify the functions of low rate, high intensity problem behavior.

PubMed

Davis, Barbara J; Kahng, Sungwoo; Schmidt, Jonathan; Bowman, Lynn G; Boelter, Eric W

2012-01-01

Current research provides few suggestions for modifications to functional analysis procedures to accommodate low rate, high intensity problem behavior. This study examined the results of the extended duration functional analysis procedures of Kahng, Abt, and Schonbachler (2001) with six children admitted to an inpatient hospital for the treatment of severe problem behavior. Results of initial functional analyses (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) were inconclusive for all children because of low levels of responding. The altered functional analyses, which changed multiple variables including the duration of the functional analysis (i.e., 6 or 7 hrs), yielded clear behavioral functions for all six participants. These results add additional support for the utility of an altered analysis of low rate, high intensity problem behavior when standard functional analyses do not yield differentiated results.

The relationship between neurobehavioural problems of severe traumatic brain injury (TBI), family functioning and the psychological well-being of the spouse/caregiver: path model analysis.

PubMed

Anderson, Malcolm I; Parmenter, Trevor R; Mok, Magdalena

2002-09-01

This study used a modern theory of stress as a framework to strengthen the understanding of the relationship between neurobehavioural problems of TBI, family functioning and psychological distress in spouse/caregivers. The research was an ex post facto design utilising a cross-sectional methodology. Path analysis was used to determine the structural effect of neurobehavioural problems on family functioning and psychological distress. Forty-seven female and 17 male spouse/caregivers of partners with severe TBI were recruited. Spouse/caregivers who reported partners with TBI as having high levels of behavioural and cognitive problems experienced high levels of unhealthy family functioning. High levels of unhealthy family functioning were related to high levels of distress in spouse/caregivers, as family functioning had a moderate influence on psychological distress. Furthermore, indirect effects of behavioural and cognitive problems operating through family functioning intensified the level of psychological distress experienced by spouse/caregivers. Additionally, spouse/caregivers who reported high levels of behavioural, communication and social problems in their partners also experienced high levels of psychological distress. This study was significant because the impact of TBI on the spouse/caregiver from a multidimensional perspective is an important and under-researched area in the brain injury and disability field.

An adaptive response surface method for crashworthiness optimization

NASA Astrophysics Data System (ADS)

Shi, Lei; Yang, Ren-Jye; Zhu, Ping

2013-11-01

Response surface-based design optimization has been commonly used for optimizing large-scale design problems in the automotive industry. However, most response surface models are built by a limited number of design points without considering data uncertainty. In addition, the selection of a response surface in the literature is often arbitrary. This article uses a Bayesian metric to systematically select the best available response surface among several candidates in a library while considering data uncertainty. An adaptive, efficient response surface strategy, which minimizes the number of computationally intensive simulations, was developed for design optimization of large-scale complex problems. This methodology was demonstrated by a crashworthiness optimization example.

Hypovitaminosis A: international programmatic issues.

PubMed

Underwood, B A

1994-08-01

The virtual elimination of vitamin A deficiency and all its consequences is high on the political agenda as a solvable public health problem by the end of the decade. Five to six times more children in the developing world are likely to be subclinically than clinically deficient. Subclinical deficiency can be detected by newer methodological approaches. Subclinically deficient children are at increased risk of severe and fatal infections. The problem at a population level is avoidable by the appropriate selection and application of a mix of available interventions. Countries are challenged to assess, analyze and take actions to incorporate nutrition concerns into development planning to attain end-of-decade goals.

Eco-analytical Methodology in Environmental Problems Monitoring

NASA Astrophysics Data System (ADS)

Agienko, M. I.; Bondareva, E. P.; Chistyakova, G. V.; Zhironkina, O. V.; Kalinina, O. I.

2017-01-01

Among the problems common to all mankind, which solutions influence the prospects of civilization, the problem of ecological situation monitoring takes very important place. Solution of this problem requires specific methodology based on eco-analytical comprehension of global issues. Eco-analytical methodology should help searching for the optimum balance between environmental problems and accelerating scientific and technical progress. The fact that Governments, corporations, scientists and nations focus on the production and consumption of material goods cause great damage to environment. As a result, the activity of environmentalists is developing quite spontaneously, as a complement to productive activities. Therefore, the challenge posed by the environmental problems for the science is the formation of geo-analytical reasoning and the monitoring of global problems common for the whole humanity. So it is expected to find the optimal trajectory of industrial development to prevent irreversible problems in the biosphere that could stop progress of civilization.

A quality evaluation methodology of health web-pages for non-professionals.

PubMed

Currò, Vincenzo; Buonuomo, Paola Sabrina; Onesimo, Roberta; de Rose, Paola; Vituzzi, Andrea; di Tanna, Gian Luca; D'Atri, Alessandro

2004-06-01

The proposal of an evaluation methodology for determining the quality of healthcare web sites for the dissemination of medical information to non-professionals. Three (macro) factors are considered for the quality evaluation: medical contents, accountability of the authors, and usability of the web site. Starting from two results in the literature the problem of whether or not to introduce a weighting function has been investigated. This methodology has been validated on a specialized information content, i.e., sore throats, due to the large interest such a topic enjoys with target users. The World Wide Web was accessed using a meta-search system merging several search engines. A statistical analysis was made to compare the proposed methodology with the obtained ranks of the sample web pages. The statistical analysis confirms that the variables examined (per item and sub factor) show substantially similar ranks and are capable of contributing to the evaluation of the main quality macro factors. A comparison between the aggregation functions in the proposed methodology (non-weighted averages) and the weighting functions, derived from the literature, allowed us to verify the suitability of the method. The proposed methodology suggests a simple approach which can quickly award an overall quality score for medical web sites oriented to non-professionals.

New methodology for fast prediction of wheel wear evolution

NASA Astrophysics Data System (ADS)

Apezetxea, I. S.; Perez, X.; Casanueva, C.; Alonso, A.

2017-07-01

In railway applications wear prediction in the wheel-rail interface is a fundamental matter in order to study problems such as wheel lifespan and the evolution of vehicle dynamic characteristic with time. However, one of the principal drawbacks of the existing methodologies for calculating the wear evolution is the computational cost. This paper proposes a new wear prediction methodology with a reduced computational cost. This methodology is based on two main steps: the first one is the substitution of the calculations over the whole network by the calculation of the contact conditions in certain characteristic point from whose result the wheel wear evolution can be inferred. The second one is the substitution of the dynamic calculation (time integration calculations) by the quasi-static calculation (the solution of the quasi-static situation of a vehicle at a certain point which is the same that neglecting the acceleration terms in the dynamic equations). These simplifications allow a significant reduction of computational cost to be obtained while maintaining an acceptable level of accuracy (error order of 5-10%). Several case studies are analysed along the paper with the objective of assessing the proposed methodology. The results obtained in the case studies allow concluding that the proposed methodology is valid for an arbitrary vehicle running through an arbitrary track layout.

Depression following adult, non-penetrating traumatic brain injury: a meta-analysis examining methodological variables and sample characteristics.

PubMed

Osborn, A J; Mathias, J L; Fairweather-Schmidt, A K

2014-11-01

Depression is one of the most frequently reported psychological problems following TBI, however prevalence estimates vary widely. Methodological and sampling differences may explain some of this variability, but it is not known to what extent. Data from 99 studies examining the prevalence of clinically diagnosed depression (MDD/dysthymia) and self-reports of depression (clinically significant cases or depression scale scores) following adult, non-penetrating TBI were analysed, taking into consideration diagnostic criteria, measure, post-injury interval, and injury severity. Overall, 27% of people were diagnosed with MDD/dysthymia following TBI and 38% reported clinically significant levels of depression when assessed with self-report scales. Estimates of MDD/dysthymia varied according to diagnostic criteria (ICD-10: 14%; DSM-IV: 25%; DSM-III: 47%) and injury severity (mild: 16%; severe: 30%). When self-report measures were used, the prevalence of clinically significant cases of depression differed between scales (HADS: 32%; CES-D: 48%) method of administration (phone: 26%; mail 46%), post-injury interval (range: 33-42%), and injury severity (mild: 64%; severe: 39%). Depression is very common after TBI and has the potential to impact on recovery and quality of life. However, the diagnostic criteria, measure, time post-injury and injury severity, all impact on prevalence rates and must therefore be considered for benchmarking purposes. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Meta-Analyses and Orthodontic Evidence-Based Clinical Practice in the 21st Century

PubMed Central

Papadopoulos, Moschos A.

2010-01-01

Introduction: Aim of this systematic review was to assess the orthodontic related issues which currently provide the best evidence as documented by meta-analyses, by critically evaluating and discussing the methodology used in these studies. Material and Methods: Several electronic databases were searched and handsearching was also performed in order to identify the corresponding meta-analyses investigating orthodontic related subjects. In total, 197 studies were retrieved initially. After applying specific inclusion and exclusion criteria, 27 articles were identified as meta-analyses treating orthodontic-related subjects. Results: Many of these 27 papers presented sufficient quality and followed appropriate meta-analytic approaches to quantitatively synthesize data and presented adequately supported evidence. However, the methodology used in some of them presented weaknesses, limitations or deficiencies. Consequently, the topics in orthodontics which currently provide the best evidence, include some issues related to Class II or Class III treatment, treatment of transverse problems, external apical root resorption, dental anomalies, such as congenital missing teeth and tooth transposition, frequency of severe occlusal problems, nickel hypersensitivity, obstructive sleep apnea syndrome, and computer-assisted learning in orthodontic education. Conclusions: Only a few orthodontic related issues have been so far investigated by means of MAs. In addition, for some of these issues investigated in the corresponding MAs no definite conclusions could be drawn, due to significant methodological deficiencies of these studies. According to this investigation, it can be concluded that at the begin of the 21st century there is evidence for only a few orthodontic related issues as documented by meta-analyses, and more well-conducted high quality research studies are needed to produce strong evidence in order to support evidence-based clinical practice in orthodontics. PMID:21673839

Barriers to self-care in women of reproductive age with HIV/AIDS in Iran: a qualitative study.

PubMed

Oskouie, Fatemeh; Kashefi, Farzaneh; Rafii, Forough; Gouya, Mohammad Mehdi

2017-01-01

Although increasing attention is paid to HIV/AIDS, patients with HIV still experience several barriers to self-care. These barriers have been previously identified in small quantitative studies on women with HIV, but qualitative studies are required to clarify barriers to self-care. We conducted our study using the grounded theory methodological approach. A total of 28 women with HIV and their family members, were interviewed. The data were analyzed with the Corbin and Strauss method (1998). The key barriers to self-care in women with HIV/AIDS included social stigma, addiction, psychological problems, medication side-effects and financial problems. Women with HIV/AIDS face several barriers to self-care. Therefore, when designing self-care models for these women, social and financial barriers should be identified. Mental health treatment should also be incorporated into such models and patients' access to health care services should be facilitated.

Dynamic Decision Making under Uncertainty and Partial Information

DTIC Science & Technology

2017-01-30

order to address these problems, we investigated efficient computational methodologies for dynamic decision making under uncertainty and partial...information. In the course of this research, we developed and studied efficient simulation-based methodologies for dynamic decision making under...uncertainty and partial information; (ii) studied the application of these decision making models and methodologies to practical problems, such as those

Generalized Predictive and Neural Generalized Predictive Control of Aerospace Systems

NASA Technical Reports Server (NTRS)

Kelkar, Atul G.

2000-01-01

The research work presented in this thesis addresses the problem of robust control of uncertain linear and nonlinear systems using Neural network-based Generalized Predictive Control (NGPC) methodology. A brief overview of predictive control and its comparison with Linear Quadratic (LQ) control is given to emphasize advantages and drawbacks of predictive control methods. It is shown that the Generalized Predictive Control (GPC) methodology overcomes the drawbacks associated with traditional LQ control as well as conventional predictive control methods. It is shown that in spite of the model-based nature of GPC it has good robustness properties being special case of receding horizon control. The conditions for choosing tuning parameters for GPC to ensure closed-loop stability are derived. A neural network-based GPC architecture is proposed for the control of linear and nonlinear uncertain systems. A methodology to account for parametric uncertainty in the system is proposed using on-line training capability of multi-layer neural network. Several simulation examples and results from real-time experiments are given to demonstrate the effectiveness of the proposed methodology.

A Methodology and Implementation for Annotating Digital Images for Context-appropriate Use in an Academic Health Care Environment

PubMed Central

Goede, Patricia A.; Lauman, Jason R.; Cochella, Christopher; Katzman, Gregory L.; Morton, David A.; Albertine, Kurt H.

2004-01-01

Use of digital medical images has become common over the last several years, coincident with the release of inexpensive, mega-pixel quality digital cameras and the transition to digital radiology operation by hospitals. One problem that clinicians, medical educators, and basic scientists encounter when handling images is the difficulty of using business and graphic arts commercial-off-the-shelf (COTS) software in multicontext authoring and interactive teaching environments. The authors investigated and developed software-supported methodologies to help clinicians, medical educators, and basic scientists become more efficient and effective in their digital imaging environments. The software that the authors developed provides the ability to annotate images based on a multispecialty methodology for annotation and visual knowledge representation. This annotation methodology is designed by consensus, with contributions from the authors and physicians, medical educators, and basic scientists in the Departments of Radiology, Neurobiology and Anatomy, Dermatology, and Ophthalmology at the University of Utah. The annotation methodology functions as a foundation for creating, using, reusing, and extending dynamic annotations in a context-appropriate, interactive digital environment. The annotation methodology supports the authoring process as well as output and presentation mechanisms. The annotation methodology is the foundation for a Windows implementation that allows annotated elements to be represented as structured eXtensible Markup Language and stored separate from the image(s). PMID:14527971

A hierarchical modeling methodology for the definition and selection of requirements

NASA Astrophysics Data System (ADS)

Dufresne, Stephane

This dissertation describes the development of a requirements analysis methodology that takes into account the concept of operations and the hierarchical decomposition of aerospace systems. At the core of the methodology, the Analytic Network Process (ANP) is used to ensure the traceability between the qualitative and quantitative information present in the hierarchical model. The proposed methodology is implemented to the requirements definition of a hurricane tracker Unmanned Aerial Vehicle. Three research objectives are identified in this work; (1) improve the requirements mapping process by matching the stakeholder expectations with the concept of operations, systems and available resources; (2) reduce the epistemic uncertainty surrounding the requirements and requirements mapping; and (3) improve the requirements down-selection process by taking into account the level of importance of the criteria and the available resources. Several challenges are associated with the identification and definition of requirements. The complexity of the system implies that a large number of requirements are needed to define the systems. These requirements are defined early in the conceptual design, where the level of knowledge is relatively low and the level of uncertainty is large. The proposed methodology intends to increase the level of knowledge and reduce the level of uncertainty by guiding the design team through a structured process. To address these challenges, a new methodology is created to flow-down the requirements from the stakeholder expectations to the systems alternatives. A taxonomy of requirements is created to classify the information gathered during the problem definition. Subsequently, the operational and systems functions and measures of effectiveness are integrated to a hierarchical model to allow the traceability of the information. Monte Carlo methods are used to evaluate the variations of the hierarchical model elements and consequently reduce the epistemic uncertainty. The proposed methodology is applied to the design of a hurricane tracker Unmanned Aerial Vehicles to demonstrate the origin and impact of requirements on the concept of operations and systems alternatives. This research demonstrates that the hierarchical modeling methodology provides a traceable flow-down of the requirements from the problem definition to the systems alternatives phases of conceptual design.

Review of auditory subliminal psychodynamic activation experiments.

PubMed

Fudin, R; Benjamin, C

1991-12-01

Subliminal psychodynamic activation experiments using auditory stimuli have yielded only a modicum of support for the contention that such activation produces predictable behavioral changes. Problems in many auditory subliminal psychodynamic activation experiments indicate that those predictions have not been tested adequately. The auditory mode of presentation, however, has several methodological advantages over the visual one, the method used in the vast majority of subliminal psychodynamic activation experiments. Consequently, it should be considered in subsequent research in this area.

A geometric multigrid preconditioning strategy for DPG system matrices

DOE PAGES

Roberts, Nathan V.; Chan, Jesse

2017-08-23

Here, the discontinuous Petrov–Galerkin (DPG) methodology of Demkowicz and Gopalakrishnan (2010, 2011) guarantees the optimality of the solution in an energy norm, and provides several features facilitating adaptive schemes. A key question that has not yet been answered in general – though there are some results for Poisson, e.g.– is how best to precondition the DPG system matrix, so that iterative solvers may be used to allow solution of large-scale problems.

JPRS Report, Soviet Union, Sociological Studies, No. 5, September-October 1987

DTIC Science & Technology

1988-06-10

of the Methodology and History of Sociology of the Institute of Sociological Research, USSR Academy of Sciences, author of the books "Tekhnika i...the problem is perpetuated. It is no secret that the history of several liberal arts institutes of the USSR Academy of Sciences in the last few...most important revolutionary process since Great October, is that it, for the first time in our country’s history , is not only creating the

Methodological issues in the study of violence against women

PubMed Central

Ruiz‐Pérez, Isabel; Plazaola‐Castaño, Juncal; Vives‐Cases, Carmen

2007-01-01

The objective of this paper is to review the methodological issues that arise when studying violence against women as a public health problem, focusing on intimate partner violence (IPV), since this is the form of violence that has the greatest consequences at a social and political level. The paper focuses first on the problems of defining what is meant by IPV. Secondly, the paper describes the difficulties in assessing the magnitude of the problem. Obtaining reliable data on this type of violence is a complex task, because of the methodological issues derived from the very nature of the phenomenon, such as the private, intimate context in which this violence often takes place, which means the problem cannot be directly observed. Finally, the paper examines the limitations and bias in research on violence, including the lack of consensus with regard to measuring events that may or may not represent a risk factor for violence against women or the methodological problem related to the type of sampling used in both aetiological and prevalence studies. PMID:18000113

New approaches to some methodological problems of meteor science

NASA Technical Reports Server (NTRS)

Meisel, David D.

1987-01-01

Several low cost approaches to continuous radioscatter monitoring of the incoming meteor flux are described. Preliminary experiments were attempted using standard time frequency stations WWVH and CHU (on frequencies near 15 MHz) during nighttime hours. Around-the-clock monitoring using the international standard aeronautical beacon frequency of 75 MHz was also attempted. The techniques are simple and can be managed routinely by amateur astronomers with relatively little technical expertise. Time series analysis can now be performed using relatively inexpensive microcomputers. Several algorithmic approaches to the analysis of meteor rates are discussed. Methods of obtaining optimal filter predictions of future meteor flux are also discussed.

Ultrasensitive low noise voltage amplifier for spectral analysis.

PubMed

Giusi, G; Crupi, F; Pace, C

2008-08-01

Recently we have proposed several voltage noise measurement methods that allow, at least in principle, the complete elimination of the noise introduced by the measurement amplifier. The most severe drawback of these methods is that they require a multistep measurement procedure. Since environmental conditions may change in the different measurement steps, the final result could be affected by these changes. This problem is solved by the one-step voltage noise measurement methodology based on a novel amplifier topology proposed in this paper. Circuit implementations for the amplifier building blocks based on operational amplifiers are critically discussed. The proposed approach is validated through measurements performed on a prototype circuit.

Dealing With Shallow-Water Flow in the Deepwater Gulf of Mexico

NASA Astrophysics Data System (ADS)

Ostermeier, R.

2006-05-01

Some of the Shell experience in dealing with the shallow-water flow problem in the Deepwater Gulf of Mexico (GOM) will be presented. The nature of the problem, including areal extent and over-pressuring mechanisms, will be discussed. Methods for sand prediction and shallow sediment and flow characterization will be reviewed. These include seismic techniques, the use of geo-technical wells, regional trends, and various MWD methods. Some examples of flow incidents with pertinent drilling issues, including well failures and abandonment, will be described. To address the shallow-water flow problem, Shell created a multi-disciplinary team of specialists in geology, geophysics, petrophysics, drilling, and civil engineering. The team developed several methodologies to deal with various aspects of the problem. These include regional trends and data bases, shallow seismic interpretation and sand prediction, well site and casing point selection, geo-technical well design and data interpretation, logging program design and interpretation, cementing design and fluids formulation, methods for remediation and mitigation of lost circulation, and so on. Shell's extensive Deepwater GOM drilling experience has lead to new understanding of the problem. Examples include delineation of trends in shallow water flow occurrence and severity, trends and departures in PP/FG, rock properties pertaining to seismic identification of sands, and so on. New knowledge has also been acquired through the use of geo-technical wells. One example is the observed rapid onset and growth of over-pressures below the mudline. Total trouble costs due to shallow water flow for all GOM operators almost certainly runs into the several hundred million dollars. Though the problem remains a concern, advances in our knowledge and understanding make it a problem that is manageable and not the "show stopper" once feared.

Training effectiveness assessment: Methodological problems and issues

NASA Technical Reports Server (NTRS)

Cross, Kenneth D.

1992-01-01

The U.S. military uses a large number of simulators to train and sustain the flying skills of helicopter pilots. Despite the enormous resources required to purchase, maintain, and use those simulators, little effort has been expended in assessing their training effectiveness. One reason for this is the lack of an evaluation methodology that yields comprehensive and valid data at a practical cost. Some of these methodological problems and issues that arise in assessing simulator training effectiveness, as well as problems with the classical transfer-of-learning paradigm were discussed.

Using heuristic algorithms for capacity leasing and task allocation issues in telecommunication networks under fuzzy quality of service constraints

NASA Astrophysics Data System (ADS)

Huseyin Turan, Hasan; Kasap, Nihat; Savran, Huseyin

2014-03-01

Nowadays, every firm uses telecommunication networks in different amounts and ways in order to complete their daily operations. In this article, we investigate an optimisation problem that a firm faces when acquiring network capacity from a market in which there exist several network providers offering different pricing and quality of service (QoS) schemes. The QoS level guaranteed by network providers and the minimum quality level of service, which is needed for accomplishing the operations are denoted as fuzzy numbers in order to handle the non-deterministic nature of the telecommunication network environment. Interestingly, the mathematical formulation of the aforementioned problem leads to the special case of a well-known two-dimensional bin packing problem, which is famous for its computational complexity. We propose two different heuristic solution procedures that have the capability of solving the resulting nonlinear mixed integer programming model with fuzzy constraints. In conclusion, the efficiency of each algorithm is tested in several test instances to demonstrate the applicability of the methodology.

Electromagnetic Simulation of the Near-Field Distribution around a Wind Farm

DOE PAGES

Yang, Shang-Te; Ling, Hao

2013-01-01

An efficienmore » t approach to compute the near-field distribution around and within a wind farm under plane wave excitation is proposed. To make the problem computationally tractable, several simplifying assumptions are made based on the geometry problem. By comparing the approximations against full-wave simulations at 500 MHz, it is shown that the assumptions do not introduce significant errors into the resulting near-field distribution. The near fields around a 3 × 3 wind farm are computed using the developed methodology at 150 MHz, 500 MHz, and 3 GHz. Both the multipath interference patterns and the forward shadows are predicted by the proposed method.« less

Dynamic loading and stress life analysis of permanent space station modules

NASA Astrophysics Data System (ADS)

Anisimov, A. V.; Krokhin, I. A.; Likhoded, A. I.; Malinin, A. A.; Panichkin, N. G.; Sidorov, V. V.; Titov, V. A.

2016-11-01

Some methodological approaches to solving several key problems of dynamic loading and structural strength analysis of Permanent Space Station (PSS)modules developed on the basis of the working experience of Soviet and Russian PSS and the International Space station (ISS) are presented. The solutions of the direct and semi-inverse problems of PSS structure dynamics are mathematically stated. Special attention is paid to the use of the results of ground structural strength tests of space station modules and the data on the actual flight actions on the station and its dynamic responses in the orbital operation regime. The procedure of determining the dynamics and operation life parameters of elements of the PSS modules is described.

Ethical and Legal Implications of the Methodological Crisis in Neuroimaging.

PubMed

Kellmeyer, Philipp

2017-10-01

Currently, many scientific fields such as psychology or biomedicine face a methodological crisis concerning the reproducibility, replicability, and validity of their research. In neuroimaging, similar methodological concerns have taken hold of the field, and researchers are working frantically toward finding solutions for the methodological problems specific to neuroimaging. This article examines some ethical and legal implications of this methodological crisis in neuroimaging. With respect to ethical challenges, the article discusses the impact of flawed methods in neuroimaging research in cognitive and clinical neuroscience, particularly with respect to faulty brain-based models of human cognition, behavior, and personality. Specifically examined is whether such faulty models, when they are applied to neurological or psychiatric diseases, could put patients at risk, and whether this places special obligations on researchers using neuroimaging. In the legal domain, the actual use of neuroimaging as evidence in United States courtrooms is surveyed, followed by an examination of ways that the methodological problems may create challenges for the criminal justice system. Finally, the article reviews and promotes some promising ideas and initiatives from within the neuroimaging community for addressing the methodological problems.

A Discontinuous Petrov-Galerkin Methodology for Adaptive Solutions to the Incompressible Navier-Stokes Equations

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

Roberts, Nathan V.; Demkowiz, Leszek; Moser, Robert

2015-11-15

The discontinuous Petrov-Galerkin methodology with optimal test functions (DPG) of Demkowicz and Gopalakrishnan [18, 20] guarantees the optimality of the solution in an energy norm, and provides several features facilitating adaptive schemes. Whereas Bubnov-Galerkin methods use identical trial and test spaces, Petrov-Galerkin methods allow these function spaces to differ. In DPG, test functions are computed on the fly and are chosen to realize the supremum in the inf-sup condition; the method is equivalent to a minimum residual method. For well-posed problems with sufficiently regular solutions, DPG can be shown to converge at optimal rates—the inf-sup constants governing the convergence aremore » mesh-independent, and of the same order as those governing the continuous problem [48]. DPG also provides an accurate mechanism for measuring the error, and this can be used to drive adaptive mesh refinements. We employ DPG to solve the steady incompressible Navier-Stokes equations in two dimensions, building on previous work on the Stokes equations, and focusing particularly on the usefulness of the approach for automatic adaptivity starting from a coarse mesh. We apply our approach to a manufactured solution due to Kovasznay as well as the lid-driven cavity flow, backward-facing step, and flow past a cylinder problems.« less

Systematic Review of Empirically Evaluated School-Based Gambling Education Programs.

PubMed

Keen, Brittany; Blaszczynski, Alex; Anjoul, Fadi

2017-03-01

Adolescent problem gambling prevalence rates are reportedly five times higher than in the adult population. Several school-based gambling education programs have been developed in an attempt to reduce problem gambling among adolescents; however few have been empirically evaluated. The aim of this review was to report the outcome of studies empirically evaluating gambling education programs across international jurisdictions. A systematic review following guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement searching five academic databases: PubMed, Scopus, Medline, PsycINFO, and ERIC, was conducted. A total of 20 papers and 19 studies were included after screening and exclusion criteria were applied. All studies reported intervention effects on cognitive outcomes such as knowledge, perceptions, and beliefs. Only nine of the studies attempted to measure intervention effects on behavioural outcomes, and only five of those reported significant changes in gambling behaviour. Of these five, methodological inadequacies were commonly found including brief follow-up periods, lack of control comparison in post hoc analyses, and inconsistencies and misclassifications in the measurement of gambling behaviour, including problem gambling. Based on this review, recommendations are offered for the future development and evaluation of school-based gambling education programs relating to both methodological and content design and delivery considerations.

Solving multi-objective optimization problems in conservation with the reference point method

PubMed Central

Dujardin, Yann; Chadès, Iadine

2018-01-01

Managing the biodiversity extinction crisis requires wise decision-making processes able to account for the limited resources available. In most decision problems in conservation biology, several conflicting objectives have to be taken into account. Most methods used in conservation either provide suboptimal solutions or use strong assumptions about the decision-maker’s preferences. Our paper reviews some of the existing approaches to solve multi-objective decision problems and presents new multi-objective linear programming formulations of two multi-objective optimization problems in conservation, allowing the use of a reference point approach. Reference point approaches solve multi-objective optimization problems by interactively representing the preferences of the decision-maker with a point in the criteria (objectives) space, called the reference point. We modelled and solved the following two problems in conservation: a dynamic multi-species management problem under uncertainty and a spatial allocation resource management problem. Results show that the reference point method outperforms classic methods while illustrating the use of an interactive methodology for solving combinatorial problems with multiple objectives. The method is general and can be adapted to a wide range of ecological combinatorial problems. PMID:29293650

Computer-Aided Diagnosis Systems for Lung Cancer: Challenges and Methodologies

PubMed Central

El-Baz, Ayman; Beache, Garth M.; Gimel'farb, Georgy; Suzuki, Kenji; Okada, Kazunori; Elnakib, Ahmed; Soliman, Ahmed; Abdollahi, Behnoush

2013-01-01

This paper overviews one of the most important, interesting, and challenging problems in oncology, the problem of lung cancer diagnosis. Developing an effective computer-aided diagnosis (CAD) system for lung cancer is of great clinical importance and can increase the patient's chance of survival. For this reason, CAD systems for lung cancer have been investigated in a huge number of research studies. A typical CAD system for lung cancer diagnosis is composed of four main processing steps: segmentation of the lung fields, detection of nodules inside the lung fields, segmentation of the detected nodules, and diagnosis of the nodules as benign or malignant. This paper overviews the current state-of-the-art techniques that have been developed to implement each of these CAD processing steps. For each technique, various aspects of technical issues, implemented methodologies, training and testing databases, and validation methods, as well as achieved performances, are described. In addition, the paper addresses several challenges that researchers face in each implementation step and outlines the strengths and drawbacks of the existing approaches for lung cancer CAD systems. PMID:23431282

Development of Constraint Force Equation Methodology for Application to Multi-Body Dynamics Including Launch Vehicle Stage Seperation

NASA Technical Reports Server (NTRS)

Pamadi, Bandu N.; Toniolo, Matthew D.; Tartabini, Paul V.; Roithmayr, Carlos M.; Albertson, Cindy W.; Karlgaard, Christopher D.

2016-01-01

The objective of this report is to develop and implement a physics based method for analysis and simulation of multi-body dynamics including launch vehicle stage separation. The constraint force equation (CFE) methodology discussed in this report provides such a framework for modeling constraint forces and moments acting at joints when the vehicles are still connected. Several stand-alone test cases involving various types of joints were developed to validate the CFE methodology. The results were compared with ADAMS(Registered Trademark) and Autolev, two different industry standard benchmark codes for multi-body dynamic analysis and simulations. However, these two codes are not designed for aerospace flight trajectory simulations. After this validation exercise, the CFE algorithm was implemented in Program to Optimize Simulated Trajectories II (POST2) to provide a capability to simulate end-to-end trajectories of launch vehicles including stage separation. The POST2/CFE methodology was applied to the STS-1 Space Shuttle solid rocket booster (SRB) separation and Hyper-X Research Vehicle (HXRV) separation from the Pegasus booster as a further test and validation for its application to launch vehicle stage separation problems. Finally, to demonstrate end-to-end simulation capability, POST2/CFE was applied to the ascent, orbit insertion, and booster return of a reusable two-stage-to-orbit (TSTO) vehicle concept. With these validation exercises, POST2/CFE software can be used for performing conceptual level end-to-end simulations, including launch vehicle stage separation, for problems similar to those discussed in this report.

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

DOE PAGES

Chen, Bo; Chen, Chen; Wang, Jianhui; ...

2017-07-07

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

A standard methodology for the analysis, recording, and control of verbal behavior

PubMed Central

Drash, Philip W.; Tudor, Roger M.

1991-01-01

Lack of a standard methodology has been one of the major obstacles preventing advancement of behavior analytic research in verbal behavior. This article presents a standard method for the analysis, recording, and control of verbal behavior that overcomes several major methodological problems that have hindered operant research in verbal behavior. The system divides all verbal behavior into four functional response classes, correct, error, no response, and inappropriate behavior, from which all vocal responses of a subject may be classified and consequated. The effects of contingencies of reinforcement on verbal operants within each category are made immediately visible to the researcher as changes in frequency of response. Incorporating frequency of response within each category as the unit of response allows both rate and probability of verbal response to be utilized as basic dependent variables. This method makes it possible to record and consequate verbal behavior in essentially the same way as any other operant response. It may also facilitate an experimental investigation of Skinner's verbal response categories. PMID:22477629

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

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

Chen, Bo; Chen, Chen; Wang, Jianhui

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

Conceptual, Methodological, and Ethical Problems in Communicating Uncertainty in Clinical Evidence

PubMed Central

Han, Paul K. J.

2014-01-01

The communication of uncertainty in clinical evidence is an important endeavor that poses difficult conceptual, methodological, and ethical problems. Conceptual problems include logical paradoxes in the meaning of probability and “ambiguity”— second-order uncertainty arising from the lack of reliability, credibility, or adequacy of probability information. Methodological problems include questions about optimal methods for representing fundamental uncertainties and for communicating these uncertainties in clinical practice. Ethical problems include questions about whether communicating uncertainty enhances or diminishes patient autonomy and produces net benefits or harms. This article reviews the limited but growing literature on these problems and efforts to address them and identifies key areas of focus for future research. It is argued that the critical need moving forward is for greater conceptual clarity and consistent representational methods that make the meaning of various uncertainties understandable, and for clinical interventions to support patients in coping with uncertainty in decision making. PMID:23132891

Modified teaching approach for an enhanced medical physics graduate education experience

PubMed Central

Rutel, IB

2011-01-01

Lecture-based teaching promotes a passive interaction with students. Opportunities to modify this format are available to enhance the overall learning experience for both students and instructors. The description for a discussion-based learning format is presented as it applies to a graduate curriculum with technical (formal mathematical derivation) topics. The presented hybrid method involves several techniques, including problem-based learning, modeling, and online lectures, eliminating didactic lectures. The results from an end-of-course evaluation show that the students appear to prefer the modified format over the more traditional methodology of “lecture only” contact time. These results are motivation for further refinement and continued implementation of the described methodology in the current course and potentially other courses within the department graduate curriculum. PMID:22279505

Outcomes of planetary close encounters - A systematic comparison of methodologies

NASA Technical Reports Server (NTRS)

Greenberg, Richard; Carusi, Andrea; Valsecchi, G. B.

1988-01-01

Several methods for estimating the outcomes of close planetary encounters are compared on the basis of the numerical integration of a range of encounter types. An attempt is made to lay the foundation for the development of predictive rules concerning the encounter outcomes applicable to the refinement of the statistical mechanics that apply to planet-formation and similar problems concerning planetary swarms. Attention is given to Oepik's (1976) formulation of the two-body approximation, whose predicted motion differs from the correct three-body behavior.

GRAMM-X public web server for protein–protein docking

PubMed Central

Tovchigrechko, Andrey; Vakser, Ilya A.

2006-01-01

Protein docking software GRAMM-X and its web interface () extend the original GRAMM Fast Fourier Transformation methodology by employing smoothed potentials, refinement stage, and knowledge-based scoring. The web server frees users from complex installation of database-dependent parallel software and maintaining large hardware resources needed for protein docking simulations. Docking problems submitted to GRAMM-X server are processed by a 320 processor Linux cluster. The server was extensively tested by benchmarking, several months of public use, and participation in the CAPRI server track. PMID:16845016

Seals Research at AlliedSignal

NASA Technical Reports Server (NTRS)

Ullah, M. Rifat

1996-01-01

A consortium has been formed to address seal problems in the Aerospace sector of Allied Signal, Inc. The consortium is represented by makers of Propulsion Engines, Auxiliary Power Units, Gas Turbine Starters, etc. The goal is to improve Face Seal reliability, since Face Seals have become reliability drivers in many of our product lines. Several research programs are being implemented simultaneously this year. They include: Face Seal Modeling and Analysis Methodology; Oil Cooling of Seals; Seal Tracking Dynamics; Coking Formation & Prevention; and Seal Reliability Methods.

Black youth suicide: literature review with a focus on prevention.

PubMed Central

Baker, F. M.

1990-01-01

The national rates of completed suicide in the black population between 1950 and 1981 are presented, including age-adjusted rates. Specific studies of black suicide attempters and completed suicides by blacks in several cities are discussed. Methodological problems with existing studies and national suicide statistics are presented. Proposed theories of black suicide are reviewed. Based on a summary of the characteristics of black suicide attempters reported by the literature, preventive strategies--primary, secondary, and tertiary--are presented. PMID:2204709

[The representation of population density in school atlases: a critical examination of population maps].

PubMed

Schroder, P

1997-01-01

The author critiques the way population density is represented in school atlases, focusing on those used in German-speaking countries. After a discussion of the methodological problems underlying such representations, he selects examples from several German atlases to illustrate the transmission of contradictory, misleading, or out-of-date information. He also suggests ways to improve this situation, including better teaching of underlying cartographical issues and the use of a dot system to illustrate population density.

[Methodological problems in the use of information technologies in physical education].

PubMed

Martirosov, E G; Zaĭtseva, G A

2000-01-01

The paper considers methodological problems in the use of computer technologies in physical education by applying diagnostic and consulting systems, educational and educational-and-training process automation systems, and control and self-control programmes for athletes and others.

Co-occurring Substance Abuse and Mental Health Problems among Homeless Persons: Suggestions for Research and Practice.

PubMed

Polcin, Douglas L

Communities throughout the U.S. are struggling to find solutions for serious and persistent homelessness. Alcohol and drug problems can be causes and consequences of homelessness, as well as co-occurring problems that complicate efforts to succeed in finding stable housing. Two prominent service models exist, one known as "Housing First" takes a harm reduction approach and the other known as the "linear" model typically supports a goal of abstinence from alcohol and drugs. Despite their popularity, the research supporting these models suffers from methodological problems and inconsistent findings. One purpose of this paper is to describe systematic reviews of the homelessness services literature, which illustrate weaknesses in research designs and inconsistent conclusions about the effectiveness of current models. Problems among some of the seminal studies on homelessness include poorly defined inclusion and exclusion criteria, inadequate measures of alcohol and drug use, unspecified or poorly implemented comparison conditions, and lack of procedures documenting adherence to service models. Several recent papers have suggested broader based approaches for homeless services that integrate alternatives and respond better to consumer needs. Practical considerations for implementing a broader system of services are described and peer managed recovery homes are presented as examples of services that address some of the gaps in current approaches. Three issues are identified that need more attention from researchers: 1) improving upon the methodological limitations in current studies, 2) assessing the impact of broader based, integrated services on outcome, and 3) assessing approaches to the service needs of homeless persons involved in the criminal justice system.

Co-occurring substance abuse and mental health problems among homeless persons: Suggestions for research and practice

PubMed Central

Polcin, Douglas L.

2016-01-01

Abstract Communities throughout the U.S. are struggling to find solutions for serious and persistent homelessness. Alcohol and drug problems can be causes and consequences of homelessness, as well as co-occurring problems that complicate efforts to succeed in finding stable housing. Two prominent service models exist, one known as “Housing First” takes a harm reduction approach and the other known as the “linear” model typically supports a goal of abstinence from alcohol and drugs. Despite their popularity, the research supporting these models suffers from methodological problems and inconsistent findings. One purpose of this paper is to describe systematic reviews of the homelessness services literature, which illustrate weaknesses in research designs and inconsistent conclusions about the effectiveness of current models. Problems among some of the seminal studies on homelessness include poorly defined inclusion and exclusion criteria, inadequate measures of alcohol and drug use, unspecified or poorly implemented comparison conditions, and lack of procedures documenting adherence to service models. Several recent papers have suggested broader based approaches for homeless services that integrate alternatives and respond better to consumer needs. Practical considerations for implementing a broader system of services are described and peer-managed recovery homes are presented as examples of services that address some of the gaps in current approaches. Three issues are identified that need more attention from researchers: (1) improving upon the methodological limitations in current studies, (2) assessing the impact of broader based, integrated services on outcome, and (3) assessing approaches to the service needs of homeless persons involved in the criminal justice system. PMID:27092027

Service lifetime prediction for encapsulated photovoltaic cells/minimodules

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

Czanderna, A.W.; Jorgensen, G.J.

The overall purposes of this paper are to elucidate the crucial importance of predicting the service lifetime (SLP) for photovoltaics (PV) modules and to present an outline for developing a SLP methodology for encapsulated PV cells and minimodules. The specific objectives are (a) to illustrate the generic nature of SLP for several types of solar energy conversion or conversion devices, (b) to summarize the major durability issues concerned with these devices, (c) to justify using SLP in the triad of cost, performance, and durability instead of only durability, (d) to define and explain the seven major elements that comprise amore » generic SLP methodology, (e) to provide background about implementing the SLP methodology for PV cells and minimodules including the complexity of the encapsulation problems, (f) to summarize briefly the past focus of our task for improving and/or replacing ethylene vinyl acetate (EVA) as a PV pottant, and (g) to provide an outline of our present and future studies using encapsulated PV cells and minimodules for improving the encapsulation of PV cells and predicting a service lifetime for them using the SLP methodology outlined in objective (d). By using this methodology, our major conclusion is that predicting the service lifetime of PV cells and minimodules is possible. {copyright} {ital 1997 American Institute of Physics.}« less

A novel approach based on preference-based index for interval bilevel linear programming problem.

PubMed

Ren, Aihong; Wang, Yuping; Xue, Xingsi

2017-01-01

This paper proposes a new methodology for solving the interval bilevel linear programming problem in which all coefficients of both objective functions and constraints are considered as interval numbers. In order to keep as much uncertainty of the original constraint region as possible, the original problem is first converted into an interval bilevel programming problem with interval coefficients in both objective functions only through normal variation of interval number and chance-constrained programming. With the consideration of different preferences of different decision makers, the concept of the preference level that the interval objective function is preferred to a target interval is defined based on the preference-based index. Then a preference-based deterministic bilevel programming problem is constructed in terms of the preference level and the order relation [Formula: see text]. Furthermore, the concept of a preference δ -optimal solution is given. Subsequently, the constructed deterministic nonlinear bilevel problem is solved with the help of estimation of distribution algorithm. Finally, several numerical examples are provided to demonstrate the effectiveness of the proposed approach.

Conjugate gradient based projection - A new explicit methodology for frictional contact

NASA Technical Reports Server (NTRS)

Tamma, Kumar K.; Li, Maocheng; Sha, Desong

1993-01-01

With special attention towards the applicability to parallel computation or vectorization, a new and effective explicit approach for linear complementary formulations involving a conjugate gradient based projection methodology is proposed in this study for contact problems with Coulomb friction. The overall objectives are focussed towards providing an explicit methodology of computation for the complete contact problem with friction. In this regard, the primary idea for solving the linear complementary formulations stems from an established search direction which is projected to a feasible region determined by the non-negative constraint condition; this direction is then applied to the Fletcher-Reeves conjugate gradient method resulting in a powerful explicit methodology which possesses high accuracy, excellent convergence characteristics, fast computational speed and is relatively simple to implement for contact problems involving Coulomb friction.

Spinal Cord Injury-Induced Dysautonomia via Plasticity in Paravertebral Sympathetic Postganglionic

DTIC Science & Technology

2017-10-01

their near anatomical inaccessibility. We have solved the accessibility problem with a strategic methodological advance. We will determine the extent...inaccessibility. We have solved the accessibility problem with a strategic methodological advance. We will determine the extent to which paravertebral

Human Prenatal Effects: Methodological Problems and Some Suggested Solutions

ERIC Educational Resources Information Center

Copans, Stuart A.

1974-01-01

Briefly reviews the relevant literature on human prenatal effects, describes some of the possible designs for such studies; and discusses some of the methodological problem areas: sample choice, measurement of prenatal variables, monitoring of labor and delivery, and neonatal assessment. (CS)

Overcoming an obstacle in expanding a UMLS semantic type extent.

PubMed

Chen, Yan; Gu, Huanying; Perl, Yehoshua; Geller, James

2012-02-01

This paper strives to overcome a major problem encountered by a previous expansion methodology for discovering concepts highly likely to be missing a specific semantic type assignment in the UMLS. This methodology is the basis for an algorithm that presents the discovered concepts to a human auditor for review and possible correction. We analyzed the problem of the previous expansion methodology and discovered that it was due to an obstacle constituted by one or more concepts assigned the UMLS Semantic Network semantic type Classification. A new methodology was designed that bypasses such an obstacle without a combinatorial explosion in the number of concepts presented to the human auditor for review. The new expansion methodology with obstacle avoidance was tested with the semantic type Experimental Model of Disease and found over 500 concepts missed by the previous methodology that are in need of this semantic type assignment. Furthermore, other semantic types suffering from the same major problem were discovered, indicating that the methodology is of more general applicability. The algorithmic discovery of concepts that are likely missing a semantic type assignment is possible even in the face of obstacles, without an explosion in the number of processed concepts. Copyright © 2011 Elsevier Inc. All rights reserved.

Overcoming an Obstacle in Expanding a UMLS Semantic Type Extent

PubMed Central

Chen, Yan; Gu, Huanying; Perl, Yehoshua; Geller, James

2011-01-01

This paper strives to overcome a major problem encountered by a previous expansion methodology for discovering concepts highly likely to be missing a specific semantic type assignment in the UMLS. This methodology is the basis for an algorithm that presents the discovered concepts to a human auditor for review and possible correction. We analyzed the problem of the previous expansion methodology and discovered that it was due to an obstacle constituted by one or more concepts assigned the UMLS Semantic Network semantic type Classification. A new methodology was designed that bypasses such an obstacle without a combinatorial explosion in the number of concepts presented to the human auditor for review. The new expansion methodology with obstacle avoidance was tested with the semantic type Experimental Model of Disease and found over 500 concepts missed by the previous methodology that are in need of this semantic type assignment. Furthermore, other semantic types suffering from the same major problem were discovered, indicating that the methodology is of more general applicability. The algorithmic discovery of concepts that are likely missing a semantic type assignment is possible even in the face of obstacles, without an explosion in the number of processed concepts. PMID:21925287

Typology of person-environment fit constellations: a platform addressing accessibility problems in the built environment for people with functional limitations.

PubMed

Slaug, Björn; Schilling, Oliver; Iwarsson, Susanne; Carlsson, Gunilla

2015-09-02

Making the built environment accessible for all regardless of functional capacity is an important goal for public health efforts. Considerable impediments to achieving this goal suggest the need for valid measurements of acccessibility and for greater attention to the complexity of person-environment fit issues. To address these needs, this study aimed to provide a methodological platform, useful for further research and instrument development within accessibility research. This was accomplished by the construction of a typology of problematic person-environment fit constellations, utilizing an existing methodology developed to assess and analyze accessibility problems in the built environment. By means of qualitative review and statistical methods we classified the person-environment fit components covered by an existing application which targets housing accessibility: the Housing Enabler (HE) instrument. The International Classification of Functioning, Disability and Health (ICF) was used as a conceptual framework. Qualitative classification principles were based on conceptual similarities and for quantitative analysis of similarities, Principal Component Analysis was carried out. We present a typology of problematic person-environment fit constellations classified along three dimensions: 1) accessibility problem range and severity 2) aspects of functioning 3) environmental context. As a result of the classification of the HE components, 48 typical person-environment fit constellations were recognised. The main contribution of this study is the proposed typology of person-environment fit constellations. The typology provides a methodological platform for the identification and quantification of problematic person-environment fit constellations. Its link to the globally accepted ICF classification system facilitates communication within the scientific and health care practice communities. The typology also highlights how relations between aspects of functioning and physical environmental barriers generate typical accessibility problems, and thereby furnishes a reference point for research oriented to how the built environment may be designed to be supportive for activity, participation and health.

Supporting pre-service elementary teachers in their understanding of inquiry teaching through the construction of a third discursive space

NASA Astrophysics Data System (ADS)

Greca, Ileana M.

2016-03-01

Several international reports promote the use of the inquiry teaching methodology for improvements in science education at elementary school. Nevertheless, research indicates that pre-service elementary teachers have insufficient experience with this methodology and when they try to implement it, the theory they learnt in their university education clashes with the classroom practice they observe, a problem that has also been noted with other innovative methodologies. So, it appears essential for pre-service teachers to conduct supportive reflective practice during their education to integrate theory and practice, which various studies suggest is not usually done. Our study shows how opening up a third discursive space can assist this supportive reflective practice. The third discursive space appears when pre-service teachers are involved in specific activities that allow them to contrast the discourses of theoretical knowledge taught at university with practical knowledge arising from their ideas on science and science teaching and their observations during classroom practice. The case study of three pre-service teachers shows that this strategy was fundamental in helping them to integrate theory and practice, resulting in a better understanding of the inquiry methodology and its application in the classroom.

Methodology for assessing the probability of corrosion in concrete structures on the basis of half-cell potential and concrete resistivity measurements.

PubMed

Sadowski, Lukasz

2013-01-01

In recent years, the corrosion of steel reinforcement has become a major problem in the construction industry. Therefore, much attention has been given to developing methods of predicting the service life of reinforced concrete structures. The progress of corrosion cannot be visually assessed until a crack or a delamination appears. The corrosion process can be tracked using several electrochemical techniques. Most commonly the half-cell potential measurement technique is used for this purpose. However, it is generally accepted that it should be supplemented with other techniques. Hence, a methodology for assessing the probability of corrosion in concrete slabs by means of a combination of two methods, that is, the half-cell potential method and the concrete resistivity method, is proposed. An assessment of the probability of corrosion in reinforced concrete structures carried out using the proposed methodology is presented. 200 mm thick 750 mm  ×  750 mm reinforced concrete slab specimens were investigated. Potential E corr and concrete resistivity ρ in each point of the applied grid were measured. The experimental results indicate that the proposed methodology can be successfully used to assess the probability of corrosion in concrete structures.

Statistical theory and methodology for remote sensing data analysis with special emphasis on LACIE

NASA Technical Reports Server (NTRS)

Odell, P. L.

1975-01-01

Crop proportion estimators for determining crop acreage through the use of remote sensing were evaluated. Several studies of these estimators were conducted, including an empirical comparison of the different estimators (using actual data) and an empirical study of the sensitivity (robustness) of the class of mixture estimators. The effect of missing data upon crop classification procedures is discussed in detail including a simulation of the missing data effect. The final problem addressed is that of taking yield data (bushels per acre) gathered at several yield stations and extrapolating these values over some specified large region. Computer programs developed in support of some of these activities are described.

Associating quantitative behavioral traits with gene expression in the brain: searching for diamonds in the hay.

PubMed

Reiner-Benaim, Anat; Yekutieli, Daniel; Letwin, Noah E; Elmer, Gregory I; Lee, Norman H; Kafkafi, Neri; Benjamini, Yoav

2007-09-01

Gene expression and phenotypic functionality can best be associated when they are measured quantitatively within the same experiment. The analysis of such a complex experiment is presented, searching for associations between measures of exploratory behavior in mice and gene expression in brain regions. The analysis of such experiments raises several methodological problems. First and foremost, the size of the pool of potential discoveries being screened is enormous yet only few biologically relevant findings are expected, making the problem of multiple testing especially severe. We present solutions based on screening by testing related hypotheses, then testing the hypotheses of interest. In one variant the subset is selected directly, in the other one a tree of hypotheses is tested hierarchical; both variants control the False Discovery Rate (FDR). Other problems in such experiments are in the fact that the level of data aggregation may be different for the quantitative traits (one per animal) and gene expression measurements (pooled across animals); in that the association may not be linear; and in the resolution of interest only few replications exist. We offer solutions to these problems as well. The hierarchical FDR testing strategies presented here can serve beyond the structure of our motivating example study to any complex microarray study. Supplementary data are available at Bioinformatics online.

E-therapy for mental health problems: a systematic review.

PubMed

Postel, Marloes G; de Haan, Hein A; De Jong, Cor A J

2008-09-01

The widespread availability of the Internet offers opportunities for improving access to therapy for people with mental health problems. There is a seemingly infinite supply of Internet-based interventions available on the World Wide Web. The aim of the present study is to systematically assess the methodological quality of randomized controlled trials (RCTs) concerning e-therapy for mental health problems. Two reviewers independently assessed the methodological quality of the RCTs, based on a list of criteria for the methodological quality assessment as recommended by the Cochrane Back Review Group. The search yielded 14 papers that reported RCTs concerning e-therapy for mental-health problems. The methodological quality of studies included in this review was generally low. It is concluded that e-therapy may turn out to be an appropriate therapeutic entity, but the evidence needs to be more convincing. Recommendations are made concerning the method of reporting RCTs and the need to add some content items to an e-therapy study.

Rapid space trajectory generation using a Fourier series shape-based approach

NASA Astrophysics Data System (ADS)

Taheri, Ehsan

With the insatiable curiosity of human beings to explore the universe and our solar system, it is essential to benefit from larger propulsion capabilities to execute efficient transfers and carry more scientific equipments. In the field of space trajectory optimization the fundamental advances in using low-thrust propulsion and exploiting the multi-body dynamics has played pivotal role in designing efficient space mission trajectories. The former provides larger cumulative momentum change in comparison with the conventional chemical propulsion whereas the latter results in almost ballistic trajectories with negligible amount of propellant. However, the problem of space trajectory design translates into an optimal control problem which is, in general, time-consuming and very difficult to solve. Therefore, the goal of the thesis is to address the above problem by developing a methodology to simplify and facilitate the process of finding initial low-thrust trajectories in both two-body and multi-body environments. This initial solution will not only provide mission designers with a better understanding of the problem and solution but also serves as a good initial guess for high-fidelity optimal control solvers and increases their convergence rate. Almost all of the high-fidelity solvers enjoy the existence of an initial guess that already satisfies the equations of motion and some of the most important constraints. Despite the nonlinear nature of the problem, it is sought to find a robust technique for a wide range of typical low-thrust transfers with reduced computational intensity. Another important aspect of our developed methodology is the representation of low-thrust trajectories by Fourier series with which the number of design variables reduces significantly. Emphasis is given on simplifying the equations of motion to the possible extent and avoid approximating the controls. These facts contribute to speeding up the solution finding procedure. Several example applications of two and three-dimensional two-body low-thrust transfers are considered. In addition, in the multi-body dynamic, and in particular the restricted-three-body dynamic, several Earth-to-Moon low-thrust transfers are investigated.

Fitting methods to paradigms: are ergonomics methods fit for systems thinking?

PubMed

Salmon, Paul M; Walker, Guy H; M Read, Gemma J; Goode, Natassia; Stanton, Neville A

2017-02-01

The issues being tackled within ergonomics problem spaces are shifting. Although existing paradigms appear relevant for modern day systems, it is worth questioning whether our methods are. This paper asks whether the complexities of systems thinking, a currently ubiquitous ergonomics paradigm, are outpacing the capabilities of our methodological toolkit. This is achieved through examining the contemporary ergonomics problem space and the extent to which ergonomics methods can meet the challenges posed. Specifically, five key areas within the ergonomics paradigm of systems thinking are focused on: normal performance as a cause of accidents, accident prediction, system migration, systems concepts and ergonomics in design. The methods available for pursuing each line of inquiry are discussed, along with their ability to respond to key requirements. In doing so, a series of new methodological requirements and capabilities are identified. It is argued that further methodological development is required to provide researchers and practitioners with appropriate tools to explore both contemporary and future problems. Practitioner Summary: Ergonomics methods are the cornerstone of our discipline. This paper examines whether our current methodological toolkit is fit for purpose given the changing nature of ergonomics problems. The findings provide key research and practice requirements for methodological development.

Induced abortion and adolescent mental health.

PubMed

Stotland, Nada L

2011-10-01

Induced abortion is widely believed - by the public, healthcare professionals, and policy-makers - to lead to adverse mental health sequelae. This belief is false, as it applies both to adult women and adolescents. However, it has been used to rationalize, and been quoted in, restrictive and intrusive legislation in several states and in proposed federal legislation. It is essential for gynecologists to have accurate information, as clinicians, for their patients, and, as key experts, for policy makers. New articles concluding that there are adverse psychological outcomes from induced abortion continue to be published. The methodological flaws in these articles are so serious as to invalidate those conclusions. Several recent scholarly analyses detail these flaws. Methodologically sound studies and reviews continue to demonstrate that psychosocial problems play a role in unwanted conception and the decision to abort unwanted pregnancies but are not the result of abortion. Clinicians may have to reassure patients making decisions about their pregnancies that abortion does not cause psychiatric illness. They can do so on the basis of recent analyses substantiating that finding. (C) 2011 Lippincott Williams & Wilkins, Inc.

Extending substructure based iterative solvers to multiple load and repeated analyses

NASA Technical Reports Server (NTRS)

Farhat, Charbel

1993-01-01

Direct solvers currently dominate commercial finite element structural software, but do not scale well in the fine granularity regime targeted by emerging parallel processors. Substructure based iterative solvers--often called also domain decomposition algorithms--lend themselves better to parallel processing, but must overcome several obstacles before earning their place in general purpose structural analysis programs. One such obstacle is the solution of systems with many or repeated right hand sides. Such systems arise, for example, in multiple load static analyses and in implicit linear dynamics computations. Direct solvers are well-suited for these problems because after the system matrix has been factored, the multiple or repeated solutions can be obtained through relatively inexpensive forward and backward substitutions. On the other hand, iterative solvers in general are ill-suited for these problems because they often must restart from scratch for every different right hand side. In this paper, we present a methodology for extending the range of applications of domain decomposition methods to problems with multiple or repeated right hand sides. Basically, we formulate the overall problem as a series of minimization problems over K-orthogonal and supplementary subspaces, and tailor the preconditioned conjugate gradient algorithm to solve them efficiently. The resulting solution method is scalable, whereas direct factorization schemes and forward and backward substitution algorithms are not. We illustrate the proposed methodology with the solution of static and dynamic structural problems, and highlight its potential to outperform forward and backward substitutions on parallel computers. As an example, we show that for a linear structural dynamics problem with 11640 degrees of freedom, every time-step beyond time-step 15 is solved in a single iteration and consumes 1.0 second on a 32 processor iPSC-860 system; for the same problem and the same parallel processor, a pair of forward/backward substitutions at each step consumes 15.0 seconds.

Family and school spillover in adolescents' daily lives.

PubMed

Flook, Lisa; Fuligni, Andrew J

2008-01-01

This study examined spillover between daily family stressors and school problems among 589 ninth-grade students (mean age = 14.9 years) from Mexican, Chinese, and European backgrounds. Spillover was examined using a daily diary methodology in which adolescents reported on their school and family experiences each day for 2 weeks. Analyses using hierarchical linear modeling revealed reciprocal spillover effects between adolescents' daily functioning in the family and school domains that spanned several days. Longitudinal analyses indicated that spillover between family stressors and school problems also occurs across the high school years, from 9th to 12th grade, and that both are predictive of poorer academic performance in 12th grade. These findings have practical implications for adolescents' academic achievement trajectories and general well-being.

Increasing accuracy in the assessment of motion sickness: A construct methodology

NASA Technical Reports Server (NTRS)

Stout, Cynthia S.; Cowings, Patricia S.

1993-01-01

The purpose is to introduce a new methodology that should improve the accuracy of the assessment of motion sickness. This construct methodology utilizes both subjective reports of motion sickness and objective measures of physiological correlates to assess motion sickness. Current techniques and methods used in the framework of a construct methodology are inadequate. Current assessment techniques for diagnosing motion sickness and space motion sickness are reviewed, and attention is called to the problems with the current methods. Further, principles of psychophysiology that when applied will probably resolve some of these problems are described in detail.

Problem Solving in Biology: A Methodology

ERIC Educational Resources Information Center

Wisehart, Gary; Mandell, Mark

2008-01-01

A methodology is described that teaches science process by combining informal logic and a heuristic for rating factual reliability. This system facilitates student hypothesis formation, testing, and evaluation of results. After problem solving with this scheme, students are asked to examine and evaluate arguments for the underlying principles of…

SOME POSSIBLE APPLICATIONS OF PROJECT OUTCOMES RESEARCH METHODOLOGY

DTIC Science & Technology

Section I, refers to the possibility of using the theory and methodology of Project Outcomes to problems of strategic information. It is felt that...purposes of assessing present and future organizational effectiveness . Section IV, refers to the applications that our study may have for problems of

Characteristics of lesbian, gay, bisexual, and transgender individuals entering substance abuse treatment.

PubMed

Cochran, Bryan N; Cauce, Ana Mari

2006-03-01

Previous research has suggested that lesbian, gay, bisexual, and transgender (LGBT) individuals enter treatment for substance abuse with more severe problems than heterosexual individuals. However, methodological difficulties, particularly the difficulty of obtaining a representative sample, have limited the ability to draw conclusions about LGBT individuals who receive services for substance abuse. This study took advantage of a unique opportunity to examine a representative sample of openly LGBT clients receiving publicly funded substance abuse treatment by using data gathered by treatment providers in Washington State. Baseline differences between openly LGBT and heterosexual clients were compared in a variety of domains. Results demonstrated that openly LGBT clients enter treatment with more severe substance abuse problems, greater psychopathology, and greater medical service utilization when compared with heterosexual clients. When the analyses were stratified based on sex, different patterns of substance use and associated psychosocial characteristics emerged for the LGBT clients. Implications for provision of appropriate services and recommendations to treatment agencies are discussed in this article.

Advances in the indirect, descriptive, and experimental approaches to the functional analysis of problem behavior.

PubMed

Wightman, Jade; Julio, Flávia; Virués-Ortega, Javier

2014-05-01

Experimental functional analysis is an assessment methodology to identify the environmental factors that maintain problem behavior in individuals with developmental disabilities and in other populations. Functional analysis provides the basis for the development of reinforcement-based approaches to treatment. This article reviews the procedures, validity, and clinical implementation of the methodological variations of functional analysis and function-based interventions. We present six variations of functional analysis methodology in addition to the typical functional analysis: brief functional analysis, single-function tests, latency-based functional analysis, functional analysis of precursors, and trial-based functional analysis. We also present the three general categories of function-based interventions: extinction, antecedent manipulation, and differential reinforcement. Functional analysis methodology is a valid and efficient approach to the assessment of problem behavior and the selection of treatment strategies.

On the Soil Roughness Parameterization Problem in Soil Moisture Retrieval of Bare Surfaces from Synthetic Aperture Radar

PubMed Central

Verhoest, Niko E.C; Lievens, Hans; Wagner, Wolfgang; Álvarez-Mozos, Jesús; Moran, M. Susan; Mattia, Francesco

2008-01-01

Synthetic Aperture Radar has shown its large potential for retrieving soil moisture maps at regional scales. However, since the backscattered signal is determined by several surface characteristics, the retrieval of soil moisture is an ill-posed problem when using single configuration imagery. Unless accurate surface roughness parameter values are available, retrieving soil moisture from radar backscatter usually provides inaccurate estimates. The characterization of soil roughness is not fully understood, and a large range of roughness parameter values can be obtained for the same surface when different measurement methodologies are used. In this paper, a literature review is made that summarizes the problems encountered when parameterizing soil roughness as well as the reported impact of the errors made on the retrieved soil moisture. A number of suggestions were made for resolving issues in roughness parameterization and studying the impact of these roughness problems on the soil moisture retrieval accuracy and scale. PMID:27879932

On Multifunctional Collaborative Methods in Engineering Science

NASA Technical Reports Server (NTRS)

Ransom, Jonathan B.

2001-01-01

Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized.

Frequent methodological errors in clinical research.

PubMed

Silva Aycaguer, L C

2018-03-07

Several errors that are frequently present in clinical research are listed, discussed and illustrated. A distinction is made between what can be considered an "error" arising from ignorance or neglect, from what stems from a lack of integrity of researchers, although it is recognized and documented that it is not easy to establish when we are in a case and when in another. The work does not intend to make an exhaustive inventory of such problems, but focuses on those that, while frequent, are usually less evident or less marked in the various lists that have been published with this type of problems. It has been a decision to develop in detail the examples that illustrate the problems identified, instead of making a list of errors accompanied by an epidermal description of their characteristics. Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

Transient responses' optimization by means of set-based multi-objective evolution

NASA Astrophysics Data System (ADS)

Avigad, Gideon; Eisenstadt, Erella; Goldvard, Alex; Salomon, Shaul

2012-04-01

In this article, a novel solution to multi-objective problems involving the optimization of transient responses is suggested. It is claimed that the common approach of treating such problems by introducing auxiliary objectives overlooks tradeoffs that should be presented to the decision makers. This means that, if at some time during the responses, one of the responses is optimal, it should not be overlooked. An evolutionary multi-objective algorithm is suggested in order to search for these optimal solutions. For this purpose, state-wise domination is utilized with a new crowding measure for ordered sets being suggested. The approach is tested on both artificial as well as on real life problems in order to explain the methodology and demonstrate its applicability and importance. The results indicate that, from an engineering point of view, the approach possesses several advantages over existing approaches. Moreover, the applications highlight the importance of set-based evolution.

Methodological Problems on the Way to Integrative Human Neuroscience.

PubMed

Kotchoubey, Boris; Tretter, Felix; Braun, Hans A; Buchheim, Thomas; Draguhn, Andreas; Fuchs, Thomas; Hasler, Felix; Hastedt, Heiner; Hinterberger, Thilo; Northoff, Georg; Rentschler, Ingo; Schleim, Stephan; Sellmaier, Stephan; Tebartz Van Elst, Ludger; Tschacher, Wolfgang

2016-01-01

Neuroscience is a multidisciplinary effort to understand the structures and functions of the brain and brain-mind relations. This effort results in an increasing amount of data, generated by sophisticated technologies. However, these data enhance our descriptive knowledge , rather than improve our understanding of brain functions. This is caused by methodological gaps both within and between subdisciplines constituting neuroscience, and the atomistic approach that limits the study of macro- and mesoscopic issues. Whole-brain measurement technologies do not resolve these issues, but rather aggravate them by the complexity problem. The present article is devoted to methodological and epistemic problems that obstruct the development of human neuroscience. We neither discuss ontological questions (e.g., the nature of the mind) nor review data, except when it is necessary to demonstrate a methodological issue. As regards intradisciplinary methodological problems, we concentrate on those within neurobiology (e.g., the gap between electrical and chemical approaches to neurophysiological processes) and psychology (missing theoretical concepts). As regards interdisciplinary problems, we suggest that core disciplines of neuroscience can be integrated using systemic concepts that also entail human-environment relations. We emphasize the necessity of a meta-discussion that should entail a closer cooperation with philosophy as a discipline of systematic reflection. The atomistic reduction should be complemented by the explicit consideration of the embodiedness of the brain and the embeddedness of humans. The discussion is aimed at the development of an explicit methodology of integrative human neuroscience , which will not only link different fields and levels, but also help in understanding clinical phenomena.

Methodological Problems on the Way to Integrative Human Neuroscience

PubMed Central

Kotchoubey, Boris; Tretter, Felix; Braun, Hans A.; Buchheim, Thomas; Draguhn, Andreas; Fuchs, Thomas; Hasler, Felix; Hastedt, Heiner; Hinterberger, Thilo; Northoff, Georg; Rentschler, Ingo; Schleim, Stephan; Sellmaier, Stephan; Tebartz Van Elst, Ludger; Tschacher, Wolfgang

2016-01-01

Neuroscience is a multidisciplinary effort to understand the structures and functions of the brain and brain-mind relations. This effort results in an increasing amount of data, generated by sophisticated technologies. However, these data enhance our descriptive knowledge, rather than improve our understanding of brain functions. This is caused by methodological gaps both within and between subdisciplines constituting neuroscience, and the atomistic approach that limits the study of macro- and mesoscopic issues. Whole-brain measurement technologies do not resolve these issues, but rather aggravate them by the complexity problem. The present article is devoted to methodological and epistemic problems that obstruct the development of human neuroscience. We neither discuss ontological questions (e.g., the nature of the mind) nor review data, except when it is necessary to demonstrate a methodological issue. As regards intradisciplinary methodological problems, we concentrate on those within neurobiology (e.g., the gap between electrical and chemical approaches to neurophysiological processes) and psychology (missing theoretical concepts). As regards interdisciplinary problems, we suggest that core disciplines of neuroscience can be integrated using systemic concepts that also entail human-environment relations. We emphasize the necessity of a meta-discussion that should entail a closer cooperation with philosophy as a discipline of systematic reflection. The atomistic reduction should be complemented by the explicit consideration of the embodiedness of the brain and the embeddedness of humans. The discussion is aimed at the development of an explicit methodology of integrative human neuroscience, which will not only link different fields and levels, but also help in understanding clinical phenomena. PMID:27965548

Layer Stripping Solutions of Inverse Seismic Problems.

DTIC Science & Technology

1985-03-21

problems--more so than has generally been recognized. The subject of this thesis is the theoretical development of the . layer-stripping methodology , and...medium varies sharply at each interface, which would be expected to cause difficulties for the algorithm, since it was designed for a smoothy varying... methodology was applied in a novel way. The inverse problem considered in this chapter was that of reconstructing a layered medium from measurement of its

Emergent Aerospace Designs Using Negotiating Autonomous Agents

NASA Technical Reports Server (NTRS)

Deshmukh, Abhijit; Middelkoop, Timothy; Krothapalli, Anjaneyulu; Smith, Charles

2000-01-01

This paper presents a distributed design methodology where designs emerge as a result of the negotiations between different stake holders in the process, such as cost, performance, reliability, etc. The proposed methodology uses autonomous agents to represent design decision makers. Each agent influences specific design parameters in order to maximize their utility. Since the design parameters depend on the aggregate demand of all the agents in the system, design agents need to negotiate with others in the market economy in order to reach an acceptable utility value. This paper addresses several interesting research issues related to distributed design architectures. First, we present a flexible framework which facilitates decomposition of the design problem. Second, we present overview of a market mechanism for generating acceptable design configurations. Finally, we integrate learning mechanisms in the design process to reduce the computational overhead.

Researching Street Children: Methodological and Ethical Issues.

ERIC Educational Resources Information Center

Hutz, Claudio S.; And Others

This paper describes the ethical and methodological problems associated with studying prosocial moral reasoning of street children and children of low and high SES living with their families, and problems associated with studying sexual attitudes and behavior of street children and their knowledge of sexually transmitted diseases, especially AIDS.…

Problem-Based Learning: Lessons for Administrators, Educators and Learners

ERIC Educational Resources Information Center

Yeo, Roland

2005-01-01

Purpose: The paper aims to explore the challenges of problem-based learning (PBL) as an unconventional teaching methodology experienced by a higher learning institute in Singapore. Design/methodology/approach: The exploratory study was conducted using focus group discussions and semi-structured interviews. Four groups of people were invited to…

Assessment of capillary suction time (CST) test methodologies.

PubMed

Sawalha, O; Scholz, M

2007-12-01

The capillary suction time (CST) test is a commonly used method to measure the filterability and the easiness of removing moisture from slurry and sludge in numerous environmental and industrial applications. This study assessed several novel alterations of both the test methodology and the current standard capillary suction time (CST) apparatus. Twelve different papers including the standard Whatman No. 17 chromatographic paper were tested. The tests were run using four different types of sludge including a synthetic sludge, which was specifically developed for benchmarking purposes. The standard apparatus was altered by the introduction of a novel rectangular funnel instead of a standard circular one. A stirrer was also introduced to solve the problem of test inconsistency (e.g. high CST variability) particularly for heavy types of sludge. Results showed that several alternative papers, which are cheaper than the standard paper, can be used to estimate CST values accurately, and that the test repeatability can be improved in many cases and for different types of sludge. The introduction of the rectangular funnel demonstrated an obvious enhancement of test repeatability. The use of a stirrer to avoid sedimentation of heavy sludge did not have statistically significant impact on the CST values or the corresponding data variability. The application of synthetic sludge can support the testing of experimental methodologies and should be used for subsequent benchmarking purposes.

The Speaker Respoken: Material Rhetoric as Feminist Methodology.

ERIC Educational Resources Information Center

Collins, Vicki Tolar

1999-01-01

Presents a methodology based on the concept of "material rhetoric" that can help scholars avoid problems as they reclaim women's historical texts. Defines material rhetoric and positions it theoretically in relation to other methodologies, including bibliographical studies, reception theory, and established feminist methodologies. Illustrates…

A methodology for the assessment of manned flight simulator fidelity

NASA Technical Reports Server (NTRS)

Hess, Ronald A.; Malsbury, Terry N.

1989-01-01

A relatively simple analytical methodology for assessing the fidelity of manned flight simulators for specific vehicles and tasks is offered. The methodology is based upon an application of a structural model of the human pilot, including motion cue effects. In particular, predicted pilot/vehicle dynamic characteristics are obtained with and without simulator limitations. A procedure for selecting model parameters can be implemented, given a probable pilot control strategy. In analyzing a pair of piloting tasks for which flight and simulation data are available, the methodology correctly predicted the existence of simulator fidelity problems. The methodology permitted the analytical evaluation of a change in simulator characteristics and indicated that a major source of the fidelity problems was a visual time delay in the simulation.

Evidence-Based Psychosocial Treatments for Ethnic Minority Youth

PubMed Central

Huey, Stanley J.; Polo, Antonio J.

2008-01-01

This article reviews research on evidence-based treatments (EBTs) for ethnic minority youth using criteria from Chambless et al. (1998), Chambless et al. (1996), and Chambless and Hollon (1998). Although no well-established treatments were identified, probably efficacious or possibly efficacious treatments were found for ethnic minority youth with anxiety-related problems, attention-deficit/hyperactivity disorder, depression, conduct problems, substance use problems, trauma-related syndromes, and other clinical problems. In addition, all studies met either Nathan and Gorman's (2002) Type 1 or Type 2 methodological criteria. A brief meta-analysis showed overall treatment effects of medium magnitude (d = .44). Effects were larger when EBTs were compared to no treatment (d = .58) or psychological placebos (d = .51) versus treatment as usual (d = .22). Youth ethnicity (African American, Latino, mixed/other minority), problem type, clinical severity, diagnostic status, and culture-responsive treatment status did not moderate treatment outcome. Most studies had low statistical power and poor representation of less acculturated youth. Few tests of cultural adaptation effects have been conducted in the literature and culturally validated outcome measures are mostly lacking. Recommendations for clinical practice and future research directions are provided. PMID:18444061

A hybrid neural networks-fuzzy logic-genetic algorithm for grade estimation

NASA Astrophysics Data System (ADS)

Tahmasebi, Pejman; Hezarkhani, Ardeshir

2012-05-01

The grade estimation is a quite important and money/time-consuming stage in a mine project, which is considered as a challenge for the geologists and mining engineers due to the structural complexities in mineral ore deposits. To overcome this problem, several artificial intelligence techniques such as Artificial Neural Networks (ANN) and Fuzzy Logic (FL) have recently been employed with various architectures and properties. However, due to the constraints of both methods, they yield the desired results only under the specific circumstances. As an example, one major problem in FL is the difficulty of constructing the membership functions (MFs).Other problems such as architecture and local minima could also be located in ANN designing. Therefore, a new methodology is presented in this paper for grade estimation. This method which is based on ANN and FL is called "Coactive Neuro-Fuzzy Inference System" (CANFIS) which combines two approaches, ANN and FL. The combination of these two artificial intelligence approaches is achieved via the verbal and numerical power of intelligent systems. To improve the performance of this system, a Genetic Algorithm (GA) - as a well-known technique to solve the complex optimization problems - is also employed to optimize the network parameters including learning rate, momentum of the network and the number of MFs for each input. A comparison of these techniques (ANN, Adaptive Neuro-Fuzzy Inference System or ANFIS) with this new method (CANFIS-GA) is also carried out through a case study in Sungun copper deposit, located in East-Azerbaijan, Iran. The results show that CANFIS-GA could be a faster and more accurate alternative to the existing time-consuming methodologies for ore grade estimation and that is, therefore, suggested to be applied for grade estimation in similar problems.

A hybrid neural networks-fuzzy logic-genetic algorithm for grade estimation

PubMed Central

Tahmasebi, Pejman; Hezarkhani, Ardeshir

2012-01-01

The grade estimation is a quite important and money/time-consuming stage in a mine project, which is considered as a challenge for the geologists and mining engineers due to the structural complexities in mineral ore deposits. To overcome this problem, several artificial intelligence techniques such as Artificial Neural Networks (ANN) and Fuzzy Logic (FL) have recently been employed with various architectures and properties. However, due to the constraints of both methods, they yield the desired results only under the specific circumstances. As an example, one major problem in FL is the difficulty of constructing the membership functions (MFs).Other problems such as architecture and local minima could also be located in ANN designing. Therefore, a new methodology is presented in this paper for grade estimation. This method which is based on ANN and FL is called “Coactive Neuro-Fuzzy Inference System” (CANFIS) which combines two approaches, ANN and FL. The combination of these two artificial intelligence approaches is achieved via the verbal and numerical power of intelligent systems. To improve the performance of this system, a Genetic Algorithm (GA) – as a well-known technique to solve the complex optimization problems – is also employed to optimize the network parameters including learning rate, momentum of the network and the number of MFs for each input. A comparison of these techniques (ANN, Adaptive Neuro-Fuzzy Inference System or ANFIS) with this new method (CANFIS–GA) is also carried out through a case study in Sungun copper deposit, located in East-Azerbaijan, Iran. The results show that CANFIS–GA could be a faster and more accurate alternative to the existing time-consuming methodologies for ore grade estimation and that is, therefore, suggested to be applied for grade estimation in similar problems. PMID:25540468

[Women, health, and labor in Brazil: challenges for new action].

PubMed

Aquino, E M; Menezes, G M; Marinho, L F

1995-01-01

Despite the remarkable rise in women's participation in the labor market in Brazil, its consequences on health are still virtually unknown. This study aims to identify theoretical and methodological problems in the relationship between labor and women's health from a gender perspective. Characteristics of women's occupational placement are described and analyzed as resulting from their role in social reproduction. The study examines the development of several conciliatory strategies between paid work and housework which are discussed as potential determinants of health problems and support the need for a critical reappraisal of theoretical and methodological strategies to reach a better understanding of the complexity and specificities of women's living and working conditions. The author also stresses the role of women's recent participation in the trade union movements in defense of health, body rights, and women's issues in the workplace, as well as the need for a new framework embodied in the women's social movement. The study thus points to the challenge to produce knowledge on this subject in order to unveil the uniqueness of the national scenario marked by unemployment, informal jobs, low salaries, weak trade unions and other civil organizations, and traditional domestic and marriage relationships.

Behavioral interventions for agitation in older adults with dementia: an evaluative review.

PubMed

Spira, Adam P; Edelstein, Barry A

2006-06-01

Older adults with dementia commonly exhibit agitated behavior that puts them at risk of injury and institutionalization and is associated with caregiver stress. A range of theoretical approaches has produced numerous interventions to manage these behavior problems. This paper critically reviews the empirical literature on behavioral interventions to reduce agitation in older adults with dementia. A literature search yielded 23 articles that met inclusion criteria. These articles described interventions that targeted wandering, disruptive vocalization, physical aggression, other agitated behaviors and a combination of these behaviors. Studies are summarized individually and then evaluated. Behavioral interventions targeting agitated behavior exhibited by older adults with dementia show considerable promise. A number of methodological issues must be addressed to advance this research area. Problem areas include inconsistent use of functional assessment techniques, failure to report quantitative findings and inadequate demonstrations of experimental control. The reviewed studies collectively provide evidence that warrants optimism regarding the application of behavioral principles to the management of agitation among older adults with dementia. Although the results of some studies were mixed and several studies revealed methodological shortcomings, many of them offered innovations that can be used in future, more rigorously designed, intervention studies.

Parallel methodology to capture cyclic variability in motored engines

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

Ameen, Muhsin M.; Yang, Xiaofeng; Kuo, Tang-Wei

2016-07-28

Numerical prediction of of cycle-to-cycle variability (CCV) in SI engines is extremely challenging for two key reasons: (i) high-fidelity methods such as large eddy simulation (LES) are require to accurately capture the in-cylinder turbulent flowfield, and (ii) CCV is experienced over long timescales and hence the simulations need to be performed for hundreds of consecutive cycles. In this study, a new methodology is proposed to dissociate this long time-scale problem into several shorter time-scale problems, which can considerably reduce the computational time without sacrificing the fidelity of the simulations. The strategy is to perform multiple single-cycle simulations in parallel bymore » effectively perturbing the simulation parameters such as the initial and boundary conditions. It is shown that by perturbing the initial velocity field effectively based on the intensity of the in-cylinder turbulence, the mean and variance of the in-cylinder flowfield is captured reasonably well. Adding perturbations in the initial pressure field and the boundary pressure improves the predictions. It is shown that this new approach is able to give accurate predictions of the flowfield statistics in less than one-tenth of time required for the conventional approach of simulating consecutive engine cycles.« less

Use of Six Sigma Methodology to Reduce Appointment Lead-Time in Obstetrics Outpatient Department.

PubMed

Ortiz Barrios, Miguel A; Felizzola Jiménez, Heriberto

2016-10-01

This paper focuses on the issue of longer appointment lead-time in the obstetrics outpatient department of a maternal-child hospital in Colombia. Because of extended appointment lead-time, women with high-risk pregnancy could develop severe complications in their health status and put their babies at risk. This problem was detected through a project selection process explained in this article and to solve it, Six Sigma methodology has been used. First, the process was defined through a SIPOC diagram to identify its input and output variables. Second, six sigma performance indicators were calculated to establish the process baseline. Then, a fishbone diagram was used to determine the possible causes of the problem. These causes were validated with the aid of correlation analysis and other statistical tools. Later, improvement strategies were designed to reduce appointment lead-time in this department. Project results evidenced that average appointment lead-time reduced from 6,89 days to 4,08 days and the deviation standard dropped from 1,57 days to 1,24 days. In this way, the hospital will serve pregnant women faster, which represents a risk reduction of perinatal and maternal mortality.

A methodology to enhance electromagnetic compatibility in joint military operations

NASA Astrophysics Data System (ADS)

Buckellew, William R.

The development and validation of an improved methodology to identify, characterize, and prioritize potential joint EMI (electromagnetic interference) interactions and identify and develop solutions to reduce the effects of the interference are discussed. The methodology identifies potential EMI problems using results from field operations, historical data bases, and analytical modeling. Operational expertise, engineering analysis, and testing are used to characterize and prioritize the potential EMI problems. Results can be used to resolve potential EMI during the development and acquisition of new systems and to develop engineering fixes and operational workarounds for systems already employed. The analytic modeling portion of the methodology is a predictive process that uses progressive refinement of the analysis and the operational electronic environment to eliminate noninterfering equipment pairs, defer further analysis on pairs lacking operational significance, and resolve the remaining EMI problems. Tests are conducted on equipment pairs to ensure that the analytical models provide a realistic description of the predicted interference.

Recovery of speed of information processing in closed-head-injury patients.

PubMed

Zwaagstra, R; Schmidt, I; Vanier, M

1996-06-01

After severe traumatic brain injury, patients almost invariably demonstrate a slowing of reaction time, reflecting a slowing of central information processing. Methodological problems associated with the traditional method for the analysis of longitudinal data (MANOVA) severely complicate studies on cognitive recovery. It is argued that multilevel models are often better suited for the analysis of improvement over time in clinical settings. Multilevel models take into account individual differences in both overall performance level and recovery. These models enable individual predictions for the recovery of speed of information processing. Recovery is modelled in a group of closed-head-injury patients (N = 24). Recovery was predicted by age and severity of injury, as indicated by coma duration. Over a period up to 44 months post trauma, reaction times were found to decrease faster for patients with longer coma duration.

Prevalence and severity of behavioural symptoms in patients with Korsakoff syndrome and other alcohol-related cognitive disorders: a systematic review.

PubMed

Gerridzen, Ineke J; Moerman-van den Brink, Wiltine G; Depla, Marja F; Verschuur, Els M L; Veenhuizen, Ruth B; van der Wouden, Johannes C; Hertogh, Cees M P M; Joling, Karlijn J

2017-03-01

Experiences from clinical practice suggest that behavioural symptoms in patients with Korsakoff syndrome (KS) are a frequent problem. Knowledge about behavioural symptoms is important in understanding and managing these symptoms. The aim of this study is to review the prevalence and severity of behavioural symptoms in KS. Relevant articles were identified by searching Medline (PubMed), PsycINFO, Embase and CINAHL up to 4 June 2014. Two reviewers independently selected the studies, extracted their baseline data and assessed methodological quality using a standardized checklist. Fifteen studies fulfilled the inclusion criteria. A diversity of diagnoses was used indicating that KS and other alcohol-related cognitive disorders and terms were used interchangeably. None of the studies were primarily designed to estimate the prevalence or severity of behavioural symptoms in patients with KS. Most studies had serious methodological limitations. The reported prevalence estimates of behavioural symptoms in the included studies varied strongly. Most prevalent were depressive symptoms and disorders (2-50%, median 27%) and agitation and aggression (10-54%, median 27%). None of the reported, mean severity estimates met pathological thresholds. The highest severity estimates were found for apathy. Good quality studies on behavioural symptoms in patients with KS are lacking. Observational research designed to provide reliable estimates of the prevalence and severity of behavioural symptoms in patients with KS is needed. This could improve understanding and managing these symptoms and help care staff to better support the needs of this specific patient group. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

[The ethical reflection approach in decision-making processes in health institutes].

PubMed

Gruat, Renaud

2015-12-01

Except in the specific case of end-of-life care, the law says nothing about the way in which health professionals must carry out ethical reflection regarding the treatment of their patients. A problem-solving methodology called the "ethical reflection approach" performed over several stages can be used. The decision-making process involves the whole team and draws on the ability of each caregiver to put forward a reasoned argument, in the interest of the patient. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Megastudies, crowdsourcing, and large datasets in psycholinguistics: An overview of recent developments.

PubMed

Keuleers, Emmanuel; Balota, David A

2015-01-01

This paper introduces and summarizes the special issue on megastudies, crowdsourcing, and large datasets in psycholinguistics. We provide a brief historical overview and show how the papers in this issue have extended the field by compiling new databases and making important theoretical contributions. In addition, we discuss several studies that use text corpora to build distributional semantic models to tackle various interesting problems in psycholinguistics. Finally, as is the case across the papers, we highlight some methodological issues that are brought forth via the analyses of such datasets.

On the Treatment of Electric and Magnetic Loss in the Linear Bicharacteristic Scheme for Electromagnetics

NASA Technical Reports Server (NTRS)

Beggs, John H.

2000-01-01

The upwind leapfrog or Linear Bicharacteristic Scheme (LBS) has previously been extended to treat lossy dielectric and magnetic materials. This paper examines different methodologies for treatment of the electric loss term in the Linear Bicharacteristic Scheme for computational electromagnetics. Several different treatments of the electric loss term using the LBS are explored and compared on one-dimensional model problems involving reflection from lossy dielectric materials on both uniform and nonuniform grids. Results using these LBS implementations are also compared with the FDTD method for convenience.

Hierarchical Parallelism in Finite Difference Analysis of Heat Conduction

NASA Technical Reports Server (NTRS)

Padovan, Joseph; Krishna, Lala; Gute, Douglas

1997-01-01

Based on the concept of hierarchical parallelism, this research effort resulted in highly efficient parallel solution strategies for very large scale heat conduction problems. Overall, the method of hierarchical parallelism involves the partitioning of thermal models into several substructured levels wherein an optimal balance into various associated bandwidths is achieved. The details are described in this report. Overall, the report is organized into two parts. Part 1 describes the parallel modelling methodology and associated multilevel direct, iterative and mixed solution schemes. Part 2 establishes both the formal and computational properties of the scheme.

Intelligent Systems: Shaping the Future of Aeronautics and Space Exploration

NASA Technical Reports Server (NTRS)

Krishnakumar, Kalmanje; Lohn, Jason; Kaneshige, John

2004-01-01

Intelligent systems are nature-inspired, mathematically sound, computationally intensive problem solving tools and methodologies that have become important for NASA's future roles in Aeronautics and Space Exploration. Intelligent systems will enable safe, cost and mission-effective approaches to air& control, system design, spacecraft autonomy, robotic space exploration and human exploration of Moon, Mars, and beyond. In this talk, we will discuss intelligent system technologies and expand on the role of intelligent systems in NASA's missions. We will also present several examples of which some are highlighted m this extended abstract.

Parallelized modelling and solution scheme for hierarchically scaled simulations

NASA Technical Reports Server (NTRS)

Padovan, Joe

1995-01-01

This two-part paper presents the results of a benchmarked analytical-numerical investigation into the operational characteristics of a unified parallel processing strategy for implicit fluid mechanics formulations. This hierarchical poly tree (HPT) strategy is based on multilevel substructural decomposition. The Tree morphology is chosen to minimize memory, communications and computational effort. The methodology is general enough to apply to existing finite difference (FD), finite element (FEM), finite volume (FV) or spectral element (SE) based computer programs without an extensive rewrite of code. In addition to finding large reductions in memory, communications, and computational effort associated with a parallel computing environment, substantial reductions are generated in the sequential mode of application. Such improvements grow with increasing problem size. Along with a theoretical development of general 2-D and 3-D HPT, several techniques for expanding the problem size that the current generation of computers are capable of solving, are presented and discussed. Among these techniques are several interpolative reduction methods. It was found that by combining several of these techniques that a relatively small interpolative reduction resulted in substantial performance gains. Several other unique features/benefits are discussed in this paper. Along with Part 1's theoretical development, Part 2 presents a numerical approach to the HPT along with four prototype CFD applications. These demonstrate the potential of the HPT strategy.

Methodological Issues and Practical Problems in Conducting Research on Abused Children.

ERIC Educational Resources Information Center

Kinard, E. Milling

In order to inform policy and programs, research on child abuse must be not only methodologically rigorous, but also practically feasible. However, practical problems make child abuse research difficult to conduct. Definitions of abuse must be explicit and different types of abuse must be assessed separately. Study samples should be as…

Research Methodology in Second Language Studies: Trends, Concerns, and New Directions

ERIC Educational Resources Information Center

King, Kendall A.; Mackey, Alison

2016-01-01

The field of second language studies is using increasingly sophisticated methodological approaches to address a growing number of urgent, real-world problems. These methodological developments bring both new challenges and opportunities. This article briefly reviews recent ontological and methodological debates in the field, then builds on these…

Evaluating thermoregulation in reptiles: the fallacy of the inappropriately applied method.

PubMed

Seebacher, Frank; Shine, Richard

2004-01-01

Given the importance of heat in most biological processes, studies on thermoregulation have played a major role in understanding the ecology of ectothermic vertebrates. It is, however, difficult to assess whether body temperature is actually regulated, and several techniques have been developed that allow an objective assessment of thermoregulation. Almost all recent studies on reptiles follow a single methodology that, when used correctly, facilitates comparisons between species, climates, and so on. However, the use of operative temperatures in this methodology assumes zero heat capacity of the study animals and is, therefore, appropriate for small animals only. Operative temperatures represent potentially available body temperatures accurately for small animals but can substantially overestimate the ranges of body temperature available to larger animals whose slower rates of heating and cooling mean that they cannot reach equilibrium if they encounter operative temperatures that change rapidly through either space or time. This error may lead to serious misinterpretations of field data. We derive correction factors specific for body mass and rate of movement that can be used to estimate body temperature null distributions of larger reptiles, thereby overcoming this methodological problem.

Psychobiological operationalization of RDoC constructs: Methodological and conceptual opportunities and challenges.

PubMed

MacNamara, Annmarie; Phan, K Luan

2016-03-01

NIMH's Research Domain Criteria (RDoC) project seeks to advance the diagnosis, prevention, and treatment of mental disorders by promoting psychobiological research on dimensional constructs that might cut across traditional diagnostic boundaries (Kozak & Cuthbert, ). At the core of this approach is the notion that these dimensional constructs can be assessed across different units of analysis (e.g., genes, physiology, behavior), enriching the constructs and providing more complete explanations of clinical problems. While the conceptual aspects of RDoC have been discussed in several prior papers, its methodological aspects have received comparatively less attention. For example, how to integrate data from different units of analysis has been relatively unclear. Here, we discuss one means of psychobiologically operationalizing RDoC constructs across different units of analysis (the psychoneurometric approach; Yancey et al., ), highlighting ways in which this approach might be refined in future iterations. We conclude that there is much to be learned from this technique; however, greater attention to scale-development methods and to psychometrics will likely benefit this and other methodological approaches to combining measurements across multiple units of analysis. © 2016 Society for Psychophysiological Research.

Cation-exchange high-performance liquid chromatography for variant hemoglobins and HbF/A2: What must hematopathologists know about methodology?

PubMed

Sharma, Prashant; Das, Reena

2016-03-26

Cation-exchange high-performance liquid chromatography (CE-HPLC) is a widely used laboratory test to detect variant hemoglobins as well as quantify hemoglobins F and A2 for the diagnosis of thalassemia syndromes. It's versatility, speed, reproducibility and convenience have made CE-HPLC the method of choice to initially screen for hemoglobin disorders. Despite its popularity, several methodological aspects of the technology remain obscure to pathologists and this may have consequences in specific situations. This paper discusses the basic principles of the technique, the initial quality control steps and the interpretation of various controls and variables that are available on the instrument output. Subsequent sections are devoted to methodological considerations that arise during reporting of cases. For instance, common problems of misidentified peaks, totals crossing 100%, causes of total area being above or below acceptable limits and the importance of pre-integration region peaks are dealt with. Ultimately, CE-HPLC remains an investigation, the reporting of which combines in-depth knowledge of the biological basics with more than a working knowledge of the technological aspects of the technique.

Suicide Risk Assessment Training for Psychology Doctoral Programs: Core Competencies and a Framework for Training

PubMed Central

Cramer, Robert J.; Johnson, Shara M.; McLaughlin, Jennifer; Rausch, Emilie M.; Conroy, Mary Alice

2014-01-01

Clinical and counseling psychology programs currently lack adequate evidence-based competency goals and training in suicide risk assessment. To begin to address this problem, this article proposes core competencies and an integrated training framework that can form the basis for training and research in this area. First, we evaluate the extent to which current training is effective in preparing trainees for suicide risk assessment. Within this discussion, sample and methodological issues are reviewed. Second, as an extension of these methodological training issues, we integrate empirically- and expert-derived suicide risk assessment competencies from several sources with the goal of streamlining core competencies for training purposes. Finally, a framework for suicide risk assessment training is outlined. The approach employs Objective Structured Clinical Examination (OSCE) methodology, an approach commonly utilized in medical competency training. The training modality also proposes the Suicide Competency Assessment Form (SCAF), a training tool evaluating self- and observer-ratings of trainee core competencies. The training framework and SCAF are ripe for empirical evaluation and potential training implementation. PMID:24672588

Suicide Risk Assessment Training for Psychology Doctoral Programs: Core Competencies and a Framework for Training.

PubMed

Cramer, Robert J; Johnson, Shara M; McLaughlin, Jennifer; Rausch, Emilie M; Conroy, Mary Alice

2013-02-01

Clinical and counseling psychology programs currently lack adequate evidence-based competency goals and training in suicide risk assessment. To begin to address this problem, this article proposes core competencies and an integrated training framework that can form the basis for training and research in this area. First, we evaluate the extent to which current training is effective in preparing trainees for suicide risk assessment. Within this discussion, sample and methodological issues are reviewed. Second, as an extension of these methodological training issues, we integrate empirically- and expert-derived suicide risk assessment competencies from several sources with the goal of streamlining core competencies for training purposes. Finally, a framework for suicide risk assessment training is outlined. The approach employs Objective Structured Clinical Examination (OSCE) methodology, an approach commonly utilized in medical competency training. The training modality also proposes the Suicide Competency Assessment Form (SCAF), a training tool evaluating self- and observer-ratings of trainee core competencies. The training framework and SCAF are ripe for empirical evaluation and potential training implementation.

Eight-dimensional methodology for innovative thinking about the case and ethics of the Mount Graham, Large Binocular Telescope project.

PubMed

Berne, Rosalyn W; Raviv, Daniel

2004-04-01

This paper introduces the Eight Dimensional Methodology for Innovative Thinking (the Eight Dimensional Methodology), for innovative problem solving, as a unified approach to case analysis that builds on comprehensive problem solving knowledge from industry, business, marketing, math, science, engineering, technology, arts, and daily life. It is designed to stimulate innovation by quickly generating unique "out of the box" unexpected and high quality solutions. It gives new insights and thinking strategies to solve everyday problems faced in the workplace, by helping decision makers to see otherwise obscure alternatives and solutions. Daniel Raviv, the engineer who developed the Eight Dimensional Methodology, and paper co-author, technology ethicist Rosalyn Berne, suggest that this tool can be especially useful in identifying solutions and alternatives for particular problems of engineering, and for the ethical challenges which arise with them. First, the Eight Dimensional Methodology helps to elucidate how what may appear to be a basic engineering problem also has ethical dimensions. In addition, it offers to the engineer a methodology for penetrating and seeing new dimensions of those problems. To demonstrate the effectiveness of the Eight Dimensional Methodology as an analytical tool for thinking about ethical challenges to engineering, the paper presents the case of the construction of the Large Binocular Telescope (LBT) on Mount Graham in Arizona. Analysis of the case offers to decision makers the use of the Eight Dimensional Methodology in considering alternative solutions for how they can proceed in their goals of exploring space. It then follows that same process through the second stage of exploring the ethics of each of those different solutions. The LBT project pools resources from an international partnership of universities and research institutes for the construction and maintenance of a highly sophisticated, powerful new telescope. It will soon mark the erection of the world's largest and most powerful optical telescope, designed to see fine detail otherwise visible only from space. It also represents a controversial engineering project that is being undertaken on land considered to be sacred by the local, native Apache people. As presented, the case features the University of Virginia, and its challenges in consideration of whether and how to join the LBT project consortium.

Aeroelastic optimization methodology for viscous and turbulent flows

NASA Astrophysics Data System (ADS)

Barcelos Junior, Manuel Nascimento Dias

2007-12-01

In recent years, the development of faster computers and parallel processing allowed the application of high-fidelity analysis methods to the aeroelastic design of aircraft. However, these methods are restricted to the final design verification, mainly due to the computational cost involved in iterative design processes. Therefore, this work is concerned with the creation of a robust and efficient aeroelastic optimization methodology for inviscid, viscous and turbulent flows by using high-fidelity analysis and sensitivity analysis techniques. Most of the research in aeroelastic optimization, for practical reasons, treat the aeroelastic system as a quasi-static inviscid problem. In this work, as a first step toward the creation of a more complete aeroelastic optimization methodology for realistic problems, an analytical sensitivity computation technique was developed and tested for quasi-static aeroelastic viscous and turbulent flow configurations. Viscous and turbulent effects are included by using an averaged discretization of the Navier-Stokes equations, coupled with an eddy viscosity turbulence model. For quasi-static aeroelastic problems, the traditional staggered solution strategy has unsatisfactory performance when applied to cases where there is a strong fluid-structure coupling. Consequently, this work also proposes a solution methodology for aeroelastic and sensitivity analyses of quasi-static problems, which is based on the fixed point of an iterative nonlinear block Gauss-Seidel scheme. The methodology can also be interpreted as the solution of the Schur complement of the aeroelastic and sensitivity analyses linearized systems of equations. The methodologies developed in this work are tested and verified by using realistic aeroelastic systems.

Scenario-Based Specification and Evaluation of Architectures for Health Monitoring of Aerospace Structures

NASA Technical Reports Server (NTRS)

Mukkamala, Ravi; Sundaram, P.

2001-01-01

HUMS systems have been an area of increased research in the recent times due to two main reasons: (a) increase in the occurrences of accidents in the aerospace, and (b) stricter FAA regulations on aircrafts maintenance [2]. There are several problems associated with the maintenance of aircrafts that the HUMS systems can solve through the use of several monitoring technologies.This paper documents our methodology of employing scenarios in the specification and evaluation of architecture for HUMS. Section 2 investigates related works that use scenarios in software development. Section 3 describes how we use scenarios in our work, which is followed by a demonstration of our methods in the development of KUMS in section 4. Conclusion summarizes results.

Coping, productive time use, and negative mood among adults with severe mental illness: a daily diary study.

PubMed

Yanos, Philip T; West, Michelle L; Smith, Stephen M

2010-12-01

Most studies on coping among persons with severe mental illness have relied on retrospective self-report methods; a limitation of this methodology is susceptibility to recall bias. The purpose of the present investigation was to expand the current understanding of the impact of coping among persons with severe mental illness by examining coping strategies, mood, and social functioning (operationalized as productive time use) using a daily process design. Twenty-seven adults diagnosed with severe mental illness completed baseline clinical interviews and up to 20 days of nightly telephone interviews addressing coping and daily life. A total of 198 coping efforts were reported for 387 days. Mixed-effects regression analyses examined the association between type of daily coping strategy (problem-centered, neutral, or avoidant) and both daily proportion of time participants spent in productive activity and daily negative mood, controlling for demographic and clinical variables. The results indicated that productive time use was significantly lower on days when avoidant strategies were used, in contrast with days when problem-centered strategies and neutral strategies were used. There was no significant main effect of coping on negative mood, although there was a trend in the expected direction. Findings support the hypothesis that the types of coping strategies adults with severe mental illness use are related to better social functioning on a daily level. Copyright © 2010 Elsevier B.V. All rights reserved.

IMSF: Infinite Methodology Set Framework

NASA Astrophysics Data System (ADS)

Ota, Martin; Jelínek, Ivan

Software development is usually an integration task in enterprise environment - few software applications work autonomously now. It is usually a collaboration of heterogeneous and unstable teams. One serious problem is lack of resources, a popular result being outsourcing, ‘body shopping’, and indirectly team and team member fluctuation. Outsourced sub-deliveries easily become black boxes with no clear development method used, which has a negative impact on supportability. Such environments then often face the problems of quality assurance and enterprise know-how management. The used methodology is one of the key factors. Each methodology was created as a generalization of a number of solved projects, and each methodology is thus more or less connected with a set of task types. When the task type is not suitable, it causes problems that usually result in an undocumented ad-hoc solution. This was the motivation behind formalizing a simple process for collaborative software engineering. Infinite Methodology Set Framework (IMSF) defines the ICT business process of adaptive use of methods for classified types of tasks. The article introduces IMSF and briefly comments its meta-model.

16S rRNA beacons for bacterial monitoring during human space missions.

PubMed

Larios-Sanz, Maia; Kourentzi, Katerina D; Warmflash, David; Jones, Jeffrey; Pierson, Duane L; Willson, Richard C; Fox, George E

2007-04-01

Microorganisms are unavoidable in space environments and their presence has, at times, been a source of problems. Concerns about disease during human space missions are particularly important considering the significant changes the immune system incurs during spaceflight and the history of microbial contamination aboard the Mir space station. Additionally, these contaminants may have adverse effects on instrumentation and life-support systems. A sensitive, highly specific system to detect, characterize, and monitor these microbial populations is essential. Herein we describe a monitoring approach that uses 16S rRNA targeted molecular beacons to successfully detect several specific bacterial groupings. This methodology will greatly simplify in-flight monitoring by minimizing sample handling and processing. We also address and provide solutions to target accessibility problems encountered in hybridizations that target 16S rRNA.

The integration of automated knowledge acquisition with computer-aided software engineering for space shuttle expert systems

NASA Technical Reports Server (NTRS)

Modesitt, Kenneth L.

1990-01-01

A prediction was made that the terms expert systems and knowledge acquisition would begin to disappear over the next several years. This is not because they are falling into disuse; it is rather that practitioners are realizing that they are valuable adjuncts to software engineering, in terms of problem domains addressed, user acceptance, and in development methodologies. A specific problem was discussed, that of constructing an automated test analysis system for the Space Shuttle Main Engine. In this domain, knowledge acquisition was part of requirements systems analysis, and was performed with the aid of a powerful inductive ESBT in conjunction with a computer aided software engineering (CASE) tool. The original prediction is not a very risky one -- it has already been accomplished.

Improving electrical power systems reliability through locally controlled distributed curtailable load

NASA Astrophysics Data System (ADS)

Dehbozorgi, Mohammad Reza

2000-10-01

Improvements in power system reliability have always been of interest to both power companies and customers. Since there are no sizable electrical energy storage elements in electrical power systems, the generated power should match the load demand at any given time. Failure to meet this balance may cause severe system problems, including loss of generation and system blackouts. This thesis proposes a methodology which can respond to either loss of generation or loss of load. It is based on switching of electric water heaters using power system frequency as the controlling signal. The proposed methodology encounters, and the thesis has addressed, the following associated problems. The controller must be interfaced with the existing thermostat control. When necessary to switch on loads, the water in the tank should not be overheated. Rapid switching of blocks of load, or chattering, has been considered. The contributions of the thesis are: (A) A system has been proposed which makes a significant portion of the distributed loads connected to a power system to behave in a predetermined manner to improve the power system response during disturbances. (B) The action of the proposed system is transparent to the customers. (C) The thesis proposes a simple analysis for determining the amount of such loads which might be switched and relates this amount to the size of the disturbances which can occur in the utility. (D) The proposed system acts without any formal communication links, solely using the embedded information present system-wide. (E) The methodology of the thesis proposes switching of water heater loads based on a simple, localized frequency set-point controller. The thesis has identified the consequent problem of rapid switching of distributed loads, which is referred to as chattering. (F) Two approaches have been proposed to reduce chattering to tolerable levels. (G) A frequency controller has been designed and built according to the specifications required to switch electric water heater loads in response to power system disturbances. (H) A cost analysis for building and installing the distributed frequency controller has been carried out. (I) The proposed equipment and methodology has been implemented and tested successfully. (Abstract shortened by UMI.)

Aerodynamic shape optimization using preconditioned conjugate gradient methods

NASA Technical Reports Server (NTRS)

Burgreen, Greg W.; Baysal, Oktay

1993-01-01

In an effort to further improve upon the latest advancements made in aerodynamic shape optimization procedures, a systematic study is performed to examine several current solution methodologies as applied to various aspects of the optimization procedure. It is demonstrated that preconditioned conjugate gradient-like methodologies dramatically decrease the computational efforts required for such procedures. The design problem investigated is the shape optimization of the upper and lower surfaces of an initially symmetric (NACA-012) airfoil in inviscid transonic flow and at zero degree angle-of-attack. The complete surface shape is represented using a Bezier-Bernstein polynomial. The present optimization method then automatically obtains supercritical airfoil shapes over a variety of freestream Mach numbers. Furthermore, the best optimization strategy examined resulted in a factor of 8 decrease in computational time as well as a factor of 4 decrease in memory over the most efficient strategies in current use.

A dynamic multi-scale Markov model based methodology for remaining life prediction

NASA Astrophysics Data System (ADS)

Yan, Jihong; Guo, Chaozhong; Wang, Xing

2011-05-01

The ability to accurately predict the remaining life of partially degraded components is crucial in prognostics. In this paper, a performance degradation index is designed using multi-feature fusion techniques to represent deterioration severities of facilities. Based on this indicator, an improved Markov model is proposed for remaining life prediction. Fuzzy C-Means (FCM) algorithm is employed to perform state division for Markov model in order to avoid the uncertainty of state division caused by the hard division approach. Considering the influence of both historical and real time data, a dynamic prediction method is introduced into Markov model by a weighted coefficient. Multi-scale theory is employed to solve the state division problem of multi-sample prediction. Consequently, a dynamic multi-scale Markov model is constructed. An experiment is designed based on a Bently-RK4 rotor testbed to validate the dynamic multi-scale Markov model, experimental results illustrate the effectiveness of the methodology.

On regulators with a prescribed degree of stability. M.S. Thesis

NASA Technical Reports Server (NTRS)

Ng, P. T. P.

1981-01-01

Several important aspects of the Regulator with a Prescribed Degree of Stability (RPDS) methodology and its applications are considered. The solution of the time varying RPDS problem as well as the characterization of RPDS closed loop eigenstructure properties are obtained. Based on the asymptotic behavior of RPDS root loci, a one step algorithm for designing Regulators with Prescribed Damping Ratio (RPDR) is developed. The robustness properties of RPDS are characterized in terms of the properties of the return difference and the inverse return difference matrices for the RPDS state feedback loop. This class of regulators is found to possess excellent multiloop margins with respect to stability and degree of stability properties. The ability of RPDS design to tolerate changing operating conditions and unmodelled dynamics are illustrated with a multiterminal dc/ac power system example. The output feedback realization of RPDS requires the use of Linear Quadratic Gaussian (LQG) methodology.

Feasibility and benefits of laminar flow control on supersonic cruise airplanes

NASA Technical Reports Server (NTRS)

Powell, A. G.; Agrawal, S.; Lacey, T. R.

1989-01-01

An evaluation was made of the applicability and benefits of laminar flow control (LFC) technology to supersonic cruise airplanes. Ancillary objectives were to identify the technical issues critical to supersonic LFC application, and to determine how those issues can be addressed through flight and wind-tunnel testing. Vehicle types studied include a Mach 2.2 supersonic transport configuration, a Mach 4.0 transport, and two Mach 2-class fighter concepts. Laminar flow control methodologies developed for subsonic and transonic wing laminarization were extended and applied. No intractible aerodynamic problems were found in applying LFC to airplanes of the Mach 2 class, even ones of large size. Improvements of 12 to 17 percent in lift-drag ratios were found. Several key technical issues, such as contamination avoidance and excresence criteria were identified. Recommendations are made for their resolution. A need for an inverse supersonic wing design methodology is indicated.

Identification of Novel "Inks" for 3D Printing Using High-Throughput Screening: Bioresorbable Photocurable Polymers for Controlled Drug Delivery.

PubMed

Louzao, Iria; Koch, Britta; Taresco, Vincenzo; Ruiz-Cantu, Laura; Irvine, Derek J; Roberts, Clive J; Tuck, Christopher; Alexander, Cameron; Hague, Richard; Wildman, Ricky; Alexander, Morgan R

2018-02-28

A robust methodology is presented to identify novel biomaterials suitable for three-dimensional (3D) printing. Currently, the application of additive manufacturing is limited by the availability of functional inks, especially in the area of biomaterials; this is the first time when this method is used to tackle this problem, allowing hundreds of formulations to be readily assessed. Several functional properties, including the release of an antidepressive drug (paroxetine), cytotoxicity, and printability, are screened for 253 new ink formulations in a high-throughput format as well as mechanical properties. The selected candidates with the desirable properties are successfully scaled up using 3D printing into a range of object architectures. A full drug release study and degradability and tensile modulus experiments are presented on a simple architecture to validating the suitability of this methodology to identify printable inks for 3D printing devices with bespoke properties.

Dating Violence Prevention Programming: Directions for Future Interventions

PubMed Central

Shorey, Ryan C.; Zucosky, Heather; Brasfield, Hope; Febres, Jeniimarie; Cornelius, Tara L.; Sage, Chelsea; Stuart, Gregory L.

2012-01-01

Dating violence among college students is a widespread and destructive problem. The field of dating violence has seen a substantial rise in research over the past several years, which has improved our understanding of factors that increase risk for perpetration. Unfortunately, there has been less attention paid to dating violence prevention programming, and existing programs have been marred with methodological weaknesses and a lack of demonstrated effectiveness in reducing aggression. In hopes of sparking new research on dating violence prevention programs, the current review examines possible new avenues for dating violence prevention programming among college students. We discuss clinical interventions that have shown to be effective in reducing a number of problematic behaviors, including motivational interventions, dialectical behavior therapy, mindfulness, and bystander interventions, and how they could be applied to dating violence prevention. We also discuss methodological issues to consider when implementing dating violence prevention programs. PMID:22773916

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

Janjusic, Tommy; Kartsaklis, Christos

Memory scalability is an enduring problem and bottleneck that plagues many parallel codes. Parallel codes designed for High Performance Systems are typically designed over the span of several, and in some instances 10+, years. As a result, optimization practices which were appropriate for earlier systems may no longer be valid and thus require careful optimization consideration. Specifically, parallel codes whose memory footprint is a function of their scalability must be carefully considered for future exa-scale systems. In this paper we present a methodology and tool to study the memory scalability of parallel codes. Using our methodology we evaluate an applicationmore » s memory footprint as a function of scalability, which we coined memory efficiency, and describe our results. In particular, using our in-house tools we can pinpoint the specific application components which contribute to the application s overall memory foot-print (application data- structures, libraries, etc.).« less

[Critical of the additive model of the randomized controlled trial].

PubMed

Boussageon, Rémy; Gueyffier, François; Bejan-Angoulvant, Theodora; Felden-Dominiak, Géraldine

2008-01-01

Randomized, double-blind, placebo-controlled clinical trials are currently the best way to demonstrate the clinical effectiveness of drugs. Its methodology relies on the method of difference (John Stuart Mill), through which the observed difference between two groups (drug vs placebo) can be attributed to the pharmacological effect of the drug being tested. However, this additive model can be questioned in the event of statistical interactions between the pharmacological and the placebo effects. Evidence in different domains has shown that the placebo effect can influence the effect of the active principle. This article evaluates the methodological, clinical and epistemological consequences of this phenomenon. Topics treated include extrapolating results, accounting for heterogeneous results, demonstrating the existence of several factors in the placebo effect, the necessity to take these factors into account for given symptoms or pathologies, as well as the problem of the "specific" effect.

Scattering of clusters of spherical particles—Modeling and inverse problem solution in the Rayleigh-Gans approximation

NASA Astrophysics Data System (ADS)

Eliçabe, Guillermo E.

2013-09-01

In this work, an exact scattering model for a system of clusters of spherical particles, based on the Rayleigh-Gans approximation, has been parameterized in such a way that it can be solved in inverse form using Thikhonov Regularization to obtain the morphological parameters of the clusters. That is to say, the average number of particles per cluster, the size of the primary spherical units that form the cluster, and the Discrete Distance Distribution Function from which the z-average square radius of gyration of the system of clusters is obtained. The methodology is validated through a series of simulated and experimental examples of x-ray and light scattering that show that the proposed methodology works satisfactorily in unideal situations such as: presence of error in the measurements, presence of error in the model, and several types of unideallities present in the experimental cases.

Advanced Design Methodology for Robust Aircraft Sizing and Synthesis

NASA Technical Reports Server (NTRS)

Mavris, Dimitri N.

1997-01-01

Contract efforts are focused on refining the Robust Design Methodology for Conceptual Aircraft Design. Robust Design Simulation (RDS) was developed earlier as a potential solution to the need to do rapid trade-offs while accounting for risk, conflict, and uncertainty. The core of the simulation revolved around Response Surface Equations as approximations of bounded design spaces. An ongoing investigation is concerned with the advantages of using Neural Networks in conceptual design. Thought was also given to the development of systematic way to choose or create a baseline configuration based on specific mission requirements. Expert system was developed, which selects aerodynamics, performance and weights model from several configurations based on the user's mission requirements for subsonic civil transport. The research has also resulted in a step-by-step illustration on how to use the AMV method for distribution generation and the search for robust design solutions to multivariate constrained problems.

The Beliefs of Teachers and Daycare Staff regarding Children of Divorce: A Q Methodological Study

ERIC Educational Resources Information Center

Overland, Klara; Thorsen, Arlene Arstad; Storksen, Ingunn

2012-01-01

This Q methodological study explores beliefs of daycare staff and teachers regarding young children's reactions related to divorce. The Q factor analysis resulted in two viewpoints. Participants on the viewpoint "Child problems" believe that children show various emotional and behavioral problems related to divorce, while those on the "Structure…

The Ranking of Higher Education Institutions in Russia: Some Methodological Problems.

ERIC Educational Resources Information Center

Filinov, Nikolay B.; Ruchkina, Svetlana

2002-01-01

The ranking of higher education institutions in Russia is examined from two points of view: as a social phenomenon and as a multi-criteria decision-making problem. The first point of view introduces the idea of interested and involved parties; the second introduces certain principles on which a rational ranking methodology should be based.…

Integration of PBL Methodologies into Online Learning Courses and Programs

ERIC Educational Resources Information Center

van Oostveen, Roland; Childs, Elizabeth; Flynn, Kathleen; Clarkson, Jessica

2014-01-01

Problem-based learning (PBL) challenges traditional views of teaching and learning as the learner determines, to a large extent with support from a skilled facilitator, what topics will be explored, to what depth and which processes will be used. This paper presents the implementation of problem-based learning methodologies in an online Bachelor's…

A Novel Performance Evaluation Methodology for Single-Target Trackers.

PubMed

Kristan, Matej; Matas, Jiri; Leonardis, Ales; Vojir, Tomas; Pflugfelder, Roman; Fernandez, Gustavo; Nebehay, Georg; Porikli, Fatih; Cehovin, Luka

2016-11-01

This paper addresses the problem of single-target tracker performance evaluation. We consider the performance measures, the dataset and the evaluation system to be the most important components of tracker evaluation and propose requirements for each of them. The requirements are the basis of a new evaluation methodology that aims at a simple and easily interpretable tracker comparison. The ranking-based methodology addresses tracker equivalence in terms of statistical significance and practical differences. A fully-annotated dataset with per-frame annotations with several visual attributes is introduced. The diversity of its visual properties is maximized in a novel way by clustering a large number of videos according to their visual attributes. This makes it the most sophistically constructed and annotated dataset to date. A multi-platform evaluation system allowing easy integration of third-party trackers is presented as well. The proposed evaluation methodology was tested on the VOT2014 challenge on the new dataset and 38 trackers, making it the largest benchmark to date. Most of the tested trackers are indeed state-of-the-art since they outperform the standard baselines, resulting in a highly-challenging benchmark. An exhaustive analysis of the dataset from the perspective of tracking difficulty is carried out. To facilitate tracker comparison a new performance visualization technique is proposed.

Methodology for Assessing the Probability of Corrosion in Concrete Structures on the Basis of Half-Cell Potential and Concrete Resistivity Measurements

PubMed Central

2013-01-01

In recent years, the corrosion of steel reinforcement has become a major problem in the construction industry. Therefore, much attention has been given to developing methods of predicting the service life of reinforced concrete structures. The progress of corrosion cannot be visually assessed until a crack or a delamination appears. The corrosion process can be tracked using several electrochemical techniques. Most commonly the half-cell potential measurement technique is used for this purpose. However, it is generally accepted that it should be supplemented with other techniques. Hence, a methodology for assessing the probability of corrosion in concrete slabs by means of a combination of two methods, that is, the half-cell potential method and the concrete resistivity method, is proposed. An assessment of the probability of corrosion in reinforced concrete structures carried out using the proposed methodology is presented. 200 mm thick 750 mm  ×  750 mm reinforced concrete slab specimens were investigated. Potential E corr and concrete resistivity ρ in each point of the applied grid were measured. The experimental results indicate that the proposed methodology can be successfully used to assess the probability of corrosion in concrete structures. PMID:23766706

A theoretical-experimental methodology for assessing the sensitivity of biomedical spectral imaging platforms, assays, and analysis methods.

PubMed

Leavesley, Silas J; Sweat, Brenner; Abbott, Caitlyn; Favreau, Peter; Rich, Thomas C

2018-01-01

Spectral imaging technologies have been used for many years by the remote sensing community. More recently, these approaches have been applied to biomedical problems, where they have shown great promise. However, biomedical spectral imaging has been complicated by the high variance of biological data and the reduced ability to construct test scenarios with fixed ground truths. Hence, it has been difficult to objectively assess and compare biomedical spectral imaging assays and technologies. Here, we present a standardized methodology that allows assessment of the performance of biomedical spectral imaging equipment, assays, and analysis algorithms. This methodology incorporates real experimental data and a theoretical sensitivity analysis, preserving the variability present in biomedical image data. We demonstrate that this approach can be applied in several ways: to compare the effectiveness of spectral analysis algorithms, to compare the response of different imaging platforms, and to assess the level of target signature required to achieve a desired performance. Results indicate that it is possible to compare even very different hardware platforms using this methodology. Future applications could include a range of optimization tasks, such as maximizing detection sensitivity or acquisition speed, providing high utility for investigators ranging from design engineers to biomedical scientists. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Introducing soft systems methodology plus (SSM+): why we need it and what it can contribute.

PubMed

Braithwaite, Jeffrey; Hindle, Don; Iedema, Rick; Westbrook, Johanna I

2002-01-01

There are many complicated and seemingly intractable problems in the health care sector. Past ways to address them have involved political responses, economic restructuring, biomedical and scientific studies, and managerialist or business-oriented tools. Few methods have enabled us to develop a systematic response to problems. Our version of soft systems methodology, SSM+, seems to improve problem solving processes by providing an iterative, staged framework that emphasises collaborative learning and systems redesign involving both technical and cultural fixes.

Direct trace-elemental analysis of urine samples by laser ablation-inductively coupled plasma mass spectrometry after sample deposition on clinical filter papers.

PubMed

Aramendía, Maite; Rello, Luis; Vanhaecke, Frank; Resano, Martín

2012-10-16

Collection of biological fluids on clinical filter papers shows important advantages from a logistic point of view, although analysis of these specimens is far from straightforward. Concerning urine analysis, and particularly when direct trace elemental analysis by laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) is aimed at, several problems arise, such as lack of sensitivity or different distribution of the analytes on the filter paper, rendering obtaining reliable quantitative results quite difficult. In this paper, a novel approach for urine collection is proposed, which circumvents many of these problems. This methodology consists on the use of precut filter paper discs where large amounts of sample can be retained upon a single deposition. This provides higher amounts of the target analytes and, thus, sufficient sensitivity, and allows addition of an adequate internal standard at the clinical lab prior to analysis, therefore making it suitable for a strategy based on unsupervised sample collection and ulterior analysis at referral centers. On the basis of this sampling methodology, an analytical method was developed for the direct determination of several elements in urine (Be, Bi, Cd, Co, Cu, Ni, Sb, Sn, Tl, Pb, and V) at the low μg L(-1) level by means of LA-ICPMS. The method developed provides good results in terms of accuracy and LODs (≤1 μg L(-1) for most of the analytes tested), with a precision in the range of 15%, fit-for-purpose for clinical control analysis.

Precipitable water vapour content from ESR/SKYNET sun-sky radiometers: validation against GNSS/GPS and AERONET over three different sites in Europe

NASA Astrophysics Data System (ADS)

Campanelli, Monica; Mascitelli, Alessandra; Sanò, Paolo; Diémoz, Henri; Estellés, Victor; Federico, Stefano; Iannarelli, Anna Maria; Fratarcangeli, Francesca; Mazzoni, Augusto; Realini, Eugenio; Crespi, Mattia; Bock, Olivier; Martínez-Lozano, Jose A.; Dietrich, Stefano

2018-01-01

The estimation of the precipitable water vapour content (W) with high temporal and spatial resolution is of great interest to both meteorological and climatological studies. Several methodologies based on remote sensing techniques have been recently developed in order to obtain accurate and frequent measurements of this atmospheric parameter. Among them, the relative low cost and easy deployment of sun-sky radiometers, or sun photometers, operating in several international networks, allowed the development of automatic estimations of W from these instruments with high temporal resolution. However, the great problem of this methodology is the estimation of the sun-photometric calibration parameters. The objective of this paper is to validate a new methodology based on the hypothesis that the calibration parameters characterizing the atmospheric transmittance at 940 nm are dependent on vertical profiles of temperature, air pressure and moisture typical of each measurement site. To obtain the calibration parameters some simultaneously seasonal measurements of W, from independent sources, taken over a large range of solar zenith angle and covering a wide range of W, are needed. In this work yearly GNSS/GPS datasets were used for obtaining a table of photometric calibration constants and the methodology was applied and validated in three European ESR-SKYNET network sites, characterized by different atmospheric and climatic conditions: Rome, Valencia and Aosta. Results were validated against the GNSS/GPS and AErosol RObotic NETwork (AERONET) W estimations. In both the validations the agreement was very high, with a percentage RMSD of about 6, 13 and 8 % in the case of GPS intercomparison at Rome, Aosta and Valencia, respectively, and of 8 % in the case of AERONET comparison in Valencia. Analysing the results by W classes, the present methodology was found to clearly improve W estimation at low W content when compared against AERONET in terms of % bias, bringing the agreement with the GPS (considered the reference one) from a % bias of 5.76 to 0.52.

Life after critical illness: an overview.

PubMed

Rattray, Janice

2014-03-01

To illustrate the potential physical and psychological problems faced by patients after an episode of critical illness, highlight some of the interventions that have been tested and identify areas for future research. Recovery from critical illness is an international problem and as an issue is likely to increase. For some, recovery from critical illness is prolonged, subject to physical and psychological problems that may negatively impact upon health-related quality of life. The literature accessed for this review includes the work of a number of key researchers in the field of critical care research. These were identified from a number of sources include (1) personal knowledge of the research field accumulated over the last decade and (2) using the search engine 'The Knowledge Network Scotland'. Fatigue and weakness are significant problems for critical care survivors and are common in patients who have been in ICU for more than one week. Psychological problems include anxiety, depression, post-traumatic stress, delirium and cognitive impairment. Prevalence of these problems is difficult to establish for a number of methodological reasons that include the use of self-report questionnaires, the number of different questionnaires used and the variation in administration and timing. Certain subgroups of ICU survivors especially those at the more severe end of the illness severity spectrum are more at risk and this has been demonstrated for both physical and psychological problems. Findings from international studies of a range of potential interventions are presented. However, establishing effectiveness for most of these still has to be empirically demonstrated. What seems clear is the need for a co-ordinated, multidisciplinary, designated recovery and rehabilitation pathway that begins as soon as the patient is admitted into an intensive care unit. © 2013 John Wiley & Sons Ltd.

Agile methodology selection criteria: IT start-up case study

NASA Astrophysics Data System (ADS)

Micic, Lj

2017-05-01

Project management in modern IT companies is often based on agile methodologies which have several advantages compared to traditional methodologies such is waterfall. Having in mind that clients sometimes change project during development it is crucial for an IT company to choose carefully which methodology is going to implement and is it going to be mostly based on one or is it going got be combination of several. There are several modern and often used methodologies but among those Scrum, Kanban and XP programming are usually the most common. Sometimes companies use mostly tools and procedures from one but quite often they use some of the combination of those methodologies. Having in mind that those methodologies are just a framework they allow companies to adapt it for their specific projects as well as for other limitations. These methodologies are in limited usage Bosnia but more and more IT companies are starting to use agile methodologies because it is practice and common not just for their clients abroad but also starting to be the only option in order to deliver quality product on time. However it is always challenging which methodology or combination of several companies should implement and how to connect it to its own project, organizational framework and HR management. This paper presents one case study based on local IT start up and delivers solution based on theoretical framework and practical limitations that case company has.

Antecedents of narcotic use and addiction. A study of 898 Vietnam veterans.

PubMed

Helzer, J E; Robins, L N; Davis, D H

1976-02-01

Previous studies of predictors of narcotic abuse have been retrospective and based on samples of long-term addicts obtained from legal or medical channels. There are several methodological problems in this approach. The present study is an attempt to test certain alleged predictors of narcotic use in a cohort of 898 Vietnam veterans. The design overcomes several of the methodological weaknesses of previous studies. Eight variables which have been reported as predictors of drug use or addiction in the drug literature were inquired about during a personal interview which included the premilitary life of each subject. The antecedent variables were socioeconomic background, inner city residence, psychiatric illness, broken home, race, employment history, education and antisocial history. Using information obtained from interviews and military records, we then tested the predictive value of each of these antecedents by comparing narcotic used and addiction in Vietman and use after Vietnam in men differing with respect to each antecedent. Results indicate that some of the variables were very poor, and others very good predictors of the various levels of narcotic involvement. The predictive value and overall importance of each of the variables we tested are discussed.

Pathophysiology of primary burning mouth syndrome with special focus on taste dysfunction: a review.

PubMed

Kolkka-Palomaa, M; Jääskeläinen, S K; Laine, M A; Teerijoki-Oksa, T; Sandell, M; Forssell, H

2015-11-01

Primary burning mouth syndrome (BMS) is a chronic oral condition characterized by burning pain often accompanied with taste dysfunction and xerostomia. The most compelling evidence concerning BMS pathophysiology comes from studies on the somatosensory system using neurophysiologic or psychophysical methods such as blink reflex, thermal quantitative sensory testing, as well as functional brain imaging. They have provided convincing evidence for neuropathic involvement at several levels of the somatosensory system in BMS pain pathophysiology. The number of taste function studies trying to substantiate the subjective taste disturbances or studies on salivary factors in BMS is much more limited, and most of them suffer from definitional and methodological problems. This review aims to critically evaluate the existing literature on the pathophysiology of BMS, paying special attention to the correctness of case selection and the methodology used in published studies, and to summarize the current state of knowledge. Based on the recognition of several gaps in the current understanding of the pathophysiology of BMS especially as regards taste and pain system interactions, the review ends with future scenarios for research in this area. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

An exploratory fNIRS study with immersive virtual reality: a new method for technical implementation.

PubMed

Seraglia, Bruno; Gamberini, Luciano; Priftis, Konstantinos; Scatturin, Pietro; Martinelli, Massimiliano; Cutini, Simone

2011-01-01

For over two decades Virtual Reality (VR) has been used as a useful tool in several fields, from medical and psychological treatments, to industrial and military applications. Only in recent years researchers have begun to study the neural correlates that subtend VR experiences. Even if the functional Magnetic Resonance Imaging (fMRI) is the most common and used technique, it suffers several limitations and problems. Here we present a methodology that involves the use of a new and growing brain imaging technique, functional Near-infrared Spectroscopy (fNIRS), while participants experience immersive VR. In order to allow a proper fNIRS probe application, a custom-made VR helmet was created. To test the adapted helmet, a virtual version of the line bisection task was used. Participants could bisect the lines in a virtual peripersonal or extrapersonal space, through the manipulation of a Nintendo Wiimote ® controller in order for the participants to move a virtual laser pointer. Although no neural correlates of the dissociation between peripersonal and extrapersonal space were found, a significant hemodynamic activity with respect to the baseline was present in the right parietal and occipital areas. Both advantages and disadvantages of the presented methodology are discussed.

An efficient and accurate solution methodology for bilevel multi-objective programming problems using a hybrid evolutionary-local-search algorithm.

PubMed

Deb, Kalyanmoy; Sinha, Ankur

2010-01-01

Bilevel optimization problems involve two optimization tasks (upper and lower level), in which every feasible upper level solution must correspond to an optimal solution to a lower level optimization problem. These problems commonly appear in many practical problem solving tasks including optimal control, process optimization, game-playing strategy developments, transportation problems, and others. However, they are commonly converted into a single level optimization problem by using an approximate solution procedure to replace the lower level optimization task. Although there exist a number of theoretical, numerical, and evolutionary optimization studies involving single-objective bilevel programming problems, not many studies look at the context of multiple conflicting objectives in each level of a bilevel programming problem. In this paper, we address certain intricate issues related to solving multi-objective bilevel programming problems, present challenging test problems, and propose a viable and hybrid evolutionary-cum-local-search based algorithm as a solution methodology. The hybrid approach performs better than a number of existing methodologies and scales well up to 40-variable difficult test problems used in this study. The population sizing and termination criteria are made self-adaptive, so that no additional parameters need to be supplied by the user. The study indicates a clear niche of evolutionary algorithms in solving such difficult problems of practical importance compared to their usual solution by a computationally expensive nested procedure. The study opens up many issues related to multi-objective bilevel programming and hopefully this study will motivate EMO and other researchers to pay more attention to this important and difficult problem solving activity.

Herbal Medicine for Xerostomia in Cancer Patients: A Systematic Review of Randomized Controlled Trials.

PubMed

Park, Bongki; Noh, Hyeonseok; Choi, Dong-Jun

2018-06-01

Xerostomia (dry mouth) causes many clinical problems, including oral infections, speech difficulties, and impaired chewing and swallowing of food. Many cancer patients have complained of xerostomia induced by cancer therapy. The aim of this systematic review is to assess the efficacy of herbal medicine for the treatment of xerostomia in cancer patients. Randomized controlled trials investigating the use of herbal medicines to treat xerostomia in cancer patients were included. We searched the following 12 databases without restrictions on time or language. The risk of bias was assessed using the Cochrane Risk of Bias Tool. Twenty-five randomized controlled trials involving 1586 patients met the inclusion criteria. A total of 24 formulas were examined in the included trials. Most of the included trials were insufficiently reported in the methodology section. Five formulas were shown to significantly improve the salivary flow rate compared to comparators. Regarding the grade of xerostomia, all formulas with the exception of a Dark Plum gargle solution with normal saline were significantly effective in reducing the severity of dry mouth. Adverse events were reported in 4 trials, and adverse effects of herbal medicine were reported in 3 trials. We found herbal medicines had potential benefits for improving salivary function and reducing the severity of dry mouth in cancer patients. However, methodological limitations and a relatively small sample size reduced the strength of the evidence. More high-quality trials reporting sufficient methodological data are warranted to enforce the strength of evidence regarding the effectiveness of herbal medicines.

Rapid classification of landsat TM imagery for phase 1 stratification using the automated NDVI threshold supervised classification (ANTSC) methodology

Treesearch

William H. Cooke; Dennis M. Jacobs

2002-01-01

FIA annual inventories require rapid updating of pixel-based Phase 1 estimates. Scientists at the Southern Research Station are developing an automated methodology that uses a Normalized Difference Vegetation Index (NDVI) for identifying and eliminating problem FIA plots from the analysis. Problem plots are those that have questionable land useiland cover information....

Capturing security requirements for software systems.

PubMed

El-Hadary, Hassan; El-Kassas, Sherif

2014-07-01

Security is often an afterthought during software development. Realizing security early, especially in the requirement phase, is important so that security problems can be tackled early enough before going further in the process and avoid rework. A more effective approach for security requirement engineering is needed to provide a more systematic way for eliciting adequate security requirements. This paper proposes a methodology for security requirement elicitation based on problem frames. The methodology aims at early integration of security with software development. The main goal of the methodology is to assist developers elicit adequate security requirements in a more systematic way during the requirement engineering process. A security catalog, based on the problem frames, is constructed in order to help identifying security requirements with the aid of previous security knowledge. Abuse frames are used to model threats while security problem frames are used to model security requirements. We have made use of evaluation criteria to evaluate the resulting security requirements concentrating on conflicts identification among requirements. We have shown that more complete security requirements can be elicited by such methodology in addition to the assistance offered to developers to elicit security requirements in a more systematic way.

Capturing security requirements for software systems

PubMed Central

El-Hadary, Hassan; El-Kassas, Sherif

2014-01-01

Security is often an afterthought during software development. Realizing security early, especially in the requirement phase, is important so that security problems can be tackled early enough before going further in the process and avoid rework. A more effective approach for security requirement engineering is needed to provide a more systematic way for eliciting adequate security requirements. This paper proposes a methodology for security requirement elicitation based on problem frames. The methodology aims at early integration of security with software development. The main goal of the methodology is to assist developers elicit adequate security requirements in a more systematic way during the requirement engineering process. A security catalog, based on the problem frames, is constructed in order to help identifying security requirements with the aid of previous security knowledge. Abuse frames are used to model threats while security problem frames are used to model security requirements. We have made use of evaluation criteria to evaluate the resulting security requirements concentrating on conflicts identification among requirements. We have shown that more complete security requirements can be elicited by such methodology in addition to the assistance offered to developers to elicit security requirements in a more systematic way. PMID:25685514

Learning outcomes of "The Oncology Patient" study among nursing students: A comparison of teaching strategies.

PubMed

Roca, Judith; Reguant, Mercedes; Canet, Olga

2016-11-01

Teaching strategies are essential in order to facilitate meaningful learning and the development of high-level thinking skills in students. To compare three teaching methodologies (problem-based learning, case-based teaching and traditional methods) in terms of the learning outcomes achieved by nursing students. This quasi-experimental research was carried out in the Nursing Degree programme in a group of 74 students who explored the subject of The Oncology Patient through the aforementioned strategies. A performance test was applied based on Bloom's Revised Taxonomy. A significant correlation was found between the intragroup theoretical and theoretical-practical dimensions. Likewise, intergroup differences were related to each teaching methodology. Hence, significant differences were estimated between the traditional methodology (x-=9.13), case-based teaching (x-=12.96) and problem-based learning (x-=14.84). Problem-based learning was shown to be the most successful learning method, followed by case-based teaching and the traditional methodology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Robust Design Optimization via Failure Domain Bounding

NASA Technical Reports Server (NTRS)

Crespo, Luis G.; Kenny, Sean P.; Giesy, Daniel P.

2007-01-01

This paper extends and applies the strategies recently developed by the authors for handling constraints under uncertainty to robust design optimization. For the scope of this paper, robust optimization is a methodology aimed at problems for which some parameters are uncertain and are only known to belong to some uncertainty set. This set can be described by either a deterministic or a probabilistic model. In the methodology developed herein, optimization-based strategies are used to bound the constraint violation region using hyper-spheres and hyper-rectangles. By comparing the resulting bounding sets with any given uncertainty model, it can be determined whether the constraints are satisfied for all members of the uncertainty model (i.e., constraints are feasible) or not (i.e., constraints are infeasible). If constraints are infeasible and a probabilistic uncertainty model is available, upper bounds to the probability of constraint violation can be efficiently calculated. The tools developed enable approximating not only the set of designs that make the constraints feasible but also, when required, the set of designs for which the probability of constraint violation is below a prescribed admissible value. When constraint feasibility is possible, several design criteria can be used to shape the uncertainty model of performance metrics of interest. Worst-case, least-second-moment, and reliability-based design criteria are considered herein. Since the problem formulation is generic and the tools derived only require standard optimization algorithms for their implementation, these strategies are easily applicable to a broad range of engineering problems.

Ensemble-based data assimilation and optimal sensor placement for scalar source reconstruction

NASA Astrophysics Data System (ADS)

Mons, Vincent; Wang, Qi; Zaki, Tamer

2017-11-01

Reconstructing the characteristics of a scalar source from limited remote measurements in a turbulent flow is a problem of great interest for environmental monitoring, and is challenging due to several aspects. Firstly, the numerical estimation of the scalar dispersion in a turbulent flow requires significant computational resources. Secondly, in actual practice, only a limited number of observations are available, which generally makes the corresponding inverse problem ill-posed. Ensemble-based variational data assimilation techniques are adopted to solve the problem of scalar source localization in a turbulent channel flow at Reτ = 180 . This approach combines the components of variational data assimilation and ensemble Kalman filtering, and inherits the robustness from the former and the ease of implementation from the latter. An ensemble-based methodology for optimal sensor placement is also proposed in order to improve the condition of the inverse problem, which enhances the performances of the data assimilation scheme. This work has been partially funded by the Office of Naval Research (Grant N00014-16-1-2542) and by the National Science Foundation (Grant 1461870).

Mental Health Problems in Children with Prader-Willi Syndrome

PubMed Central

Skokauskas, Norbert; Sweeny, Eileen; Meehan, Judith; Gallagher, Louise

2012-01-01

Background: Prader-Willi Syndrome (PWS) is a genetically determined neurodevelopmental disorder, which occurs in approximately one in 22000 births. Aims: This study aimed to investigate psychiatric characteristics of children diagnosed with PWS compared with an age-, gender- and IQ-matched control group. The parents of children with PWS were assessed for psychological distress in comparison to the parents of the control group. Methodological limitations identified in previous studies were addressed in the present study. Methods: Psychiatric problems were evaluated in a sample of children with genetically confirmed PWS and an age- and IQ-matched control group using the Child Behaviour Checklist 6–18. Parental psychological distress for both groups was evaluated with the Brief Symptom Inventory. Results: Children with PWS had more severe somatic, social, and thought problems, and were more withdrawn-depressed in comparison to controls. Borderline difficulties were detected for the affective, somatic, and attention deficit-hyperactivity CBCL DSM-orientated subscales in the PWS group. Parents of PWS children, in comparison to controls, had more somatization, phobic anxiety, obsessive-compulsive, and anxiety problems. Conclusions: PWS represents a complex psychological disorder with multiple areas of disturbances. PMID:22876265

A PDE-based methodology for modeling, parameter estimation and feedback control in structural and structural acoustic systems

NASA Technical Reports Server (NTRS)

Banks, H. T.; Brown, D. E.; Metcalf, Vern L.; Silcox, R. J.; Smith, Ralph C.; Wang, Yun

1994-01-01

A problem of continued interest concerns the control of vibrations in a flexible structure and the related problem of reducing structure-borne noise in structural acoustic systems. In both cases, piezoceramic patches bonded to the structures have been successfully used as control actuators. Through the application of a controlling voltage, the patches can be used to reduce structural vibrations which in turn lead to methods for reducing structure-borne noise. A PDE-based methodology for modeling, estimating physical parameters, and implementing a feedback control scheme for problems of this type is discussed. While the illustrating example is a circular plate, the methodology is sufficiently general so as to be applicable in a variety of structural and structural acoustic systems.

Problems related to the integration of fault tolerant aircraft electronic systems

NASA Technical Reports Server (NTRS)

Bannister, J. A.; Adlakha, V.; Triyedi, K.; Alspaugh, T. A., Jr.

1982-01-01

Problems related to the design of the hardware for an integrated aircraft electronic system are considered. Taxonomies of concurrent systems are reviewed and a new taxonomy is proposed. An informal methodology intended to identify feasible regions of the taxonomic design space is described. Specific tools are recommended for use in the methodology. Based on the methodology, a preliminary strawman integrated fault tolerant aircraft electronic system is proposed. Next, problems related to the programming and control of inegrated aircraft electronic systems are discussed. Issues of system resource management, including the scheduling and allocation of real time periodic tasks in a multiprocessor environment, are treated in detail. The role of software design in integrated fault tolerant aircraft electronic systems is discussed. Conclusions and recommendations for further work are included.

Meaning and Problems of Planning

ERIC Educational Resources Information Center

Brieve, Fred J.; Johnston, A. P.

1973-01-01

Examines the educational planning process. Discusses what planning is, how methodological planning can work in education, misunderstandings about planning, and difficulties in applying the planning methodology. (DN)

On the Comparison of the Long Penetration Mode (LPM) Supersonic Counterflowing Jet to the Supersonic Screech Jet

NASA Technical Reports Server (NTRS)

Farr, Rebecca A.; Chang, Chau-Lyan.; Jones, Jess H.; Dougherty, N. Sam

2015-01-01

The authors provide a brief overview of the classic tonal screech noise problem created by underexpanded supersonic jets, briefly describing the fluid dynamic-acoustics feedback mechanism that has been long established as the basis for this well-known aeroacoustics problem. This is followed by a description of the Long Penetration Mode (LPM) supersonic underexpanded counterflowing jet phenomenon which has been demonstrated in several wind tunnel tests and modeled in several computational fluid dynamics (CFD) simulations. The authors provide evidence from test and CFD analysis of LPM that indicates that acoustics feedback and fluid interaction seen in LPM are analogous to the aeroacoustics interactions seen in screech jets. Finally, the authors propose applying certain methodologies to LPM which have been developed and successfully demonstrated in the study of screech jets and mechanically induced excitation in fluid oscillators for decades. The authors conclude that the large body of work done on jet screech, other aeroacoustic phenomena, and fluid oscillators can have direct application to the study and applications of LPM counterflowing supersonic cold flow jets.

Design risk assessment for burst-prone mines: Application in a Canadian mine

NASA Astrophysics Data System (ADS)

Cheung, David J.

A proactive stance towards improving the effectiveness and consistency of risk assessments has been adopted recently by mining companies and industry. The next 10-20 years forecasts that ore deposits accessible using shallow mining techniques will diminish. The industry continues to strive for success in "deeper" mining projects in order to keep up with the continuing demand for raw materials. Although the returns are quite profitable, many projects have been sidelined due to high uncertainty and technical risk in the mining of the mineral deposit. Several hardrock mines have faced rockbursting and seismicity problems. Within those reported, mines in countries like South Africa, Australia and Canada have documented cases of severe rockburst conditions attributed to the mining depth. Severe rockburst conditions known as "burst-prone" can be effectively managed with design. Adopting a more robust design can ameliorate the exposure of workers and equipment to adverse conditions and minimize the economic consequences, which can hinder the bottom line of an operation. This thesis presents a methodology created for assessing the design risk in burst-prone mines. The methodology includes an evaluation of relative risk ratings for scenarios with options of risk reduction through several design principles. With rockbursts being a hazard of seismic events, the methodology is based on research in the area of mining seismicity factoring in rockmass failure mechanisms, which results from a combination of mining induced stress, geological structures, rockmass properties and mining influences. The methodology was applied to case studies at Craig Mine of Xstrata Nickel in Sudbury, Ontario, which is known to contain seismically active fault zones. A customized risk assessment was created and applied to rockburst case studies, evaluating the seismic vulnerability and consequence for each case. Application of the methodology to Craig Mine demonstrates that changes in the design can reduce both exposure risk (personnel and equipment), and economical risk (revenue and costs). Fatal and catastrophic consequences can be averted through robust planning and design. Two customized approaches were developed to conduct risk assessment of case studies at Craig Mine. Firstly, the Brownfield Approach utilizes the seismic database to determine the seismic hazard from a rating system that evaluates frequency-magnitude, event size, and event-blast relation. Secondly, the Greenfield Approach utilizes the seismic database, focusing on larger magnitude events, rocktype, and geological structure. The customized Greenfield Approach can also be applied in the evaluation of design risk in deep mines with the same setting and condition as Craig Mine. Other mines with different settings and conditions can apply the principles in the methodology to evaluate design alternatives and risk reduction strategies for burst-prone mines.

School-Based Methylphenidate Placebo Protocols: Methodological and Practical Issues.

ERIC Educational Resources Information Center

Hyman, Irwin A.; Wojtowicz, Alexandra; Lee, Kee Duk; Haffner, Mary Elizabeth; Fiorello, Catherine A.; And Others

1998-01-01

Focuses on methodological issues involved in choosing instruments to monitor behavior, once a comprehensive evaluation has suggested trials on Ritalin. Case examples illustrate problems of teacher compliance in filling out measures, supplying adequate placebos, and obtaining physical cooperation. Emerging school-based methodologies are discussed…

Methodology and technical requirements of the galectin-3 test for the preoperative characterization of thyroid nodules.

PubMed

Bartolazzi, Armando; Bellotti, Carlo; Sciacchitano, Salvatore

2012-01-01

In the last decade, the β-galactosyl binding protein galectin-3 has been the object of extensive molecular, structural, and functional studies aimed to clarify its biological role in cancer. Multicenter studies also contributed to discover the potential clinical value of galectin-3 expression analysis in distinguishing, preoperatively, benign from malignant thyroid nodules. As a consequence galectin-3 is receiving significant attention as tumor marker for thyroid cancer diagnosis, but some conflicting results mostly owing to methodological problems have been published. The possibility to apply preoperatively a reliable galectin-3 test method on fine needle aspiration biopsy (FNA)-derived thyroid cells represents an important achievement. When correctly applied, the method reduces consistently the gray area of thyroid FNA cytology, contributing to avoid unnecessary thyroid surgery. Although the efficacy and reliability of the galectin-3 test method have been extensively proved in several studies, its translation in the clinical setting requires well-standardized reagents and procedures. After a decade of experimental work on galectin-3-related basic and translational research projects, the major methodological problems that may potentially impair the diagnostic performance of galectin-3 immunotargeting are highlighted and discussed in detail. A standardized protocol for a reliable galectin-3 expression analysis is finally provided. The aim of this contribution is to improve the clinical management of patients with thyroid nodules, promoting the preoperative use of a reliable galectin-3 test method as ancillary technique to conventional thyroid FNA cytology. The final goal is to decrease unnecessary thyroid surgery and its related social costs.

Use of Invariant Manifolds for Transfers Between Three-Body Systems

NASA Technical Reports Server (NTRS)

Beckman, Mark; Howell, Kathleen

2003-01-01

The Lunar L1 and L2 libration points have been proposed as gateways granting inexpensive access to interplanetary space. To date, only individual solutions to the transfer between three-body systems have been found. The methodology to solve the problem for arbitrary three-body systems and entire families of orbits does not exist. This paper presents the initial approaches to solve the general problem for single and multiple impulse transfers. Two different methods of representing and storing 7-dimensional invariant manifold data are presented. Some particular solutions are presented for the transfer problem, though the emphasis is on developing methodology for solving the general problem.

Representations of Invariant Manifolds for Applications in Three-Body Systems

NASA Technical Reports Server (NTRS)

Howell, K.; Beckman, M.; Patterson, C.; Folta, D.

2004-01-01

The Lunar L1 and L2 libration points have been proposed as gateways granting inexpensive access to interplanetary space. To date, only individual solutions to the transfer between three-body systems have been found. The methodology to solve the problem for arbitrary three-body systems and entire families of orbits is currently being studied. This paper presents an initial approach to solve the general problem for single and multiple impulse transfers. Two different methods of representing and storing the invariant manifold data are presented. Some particular solutions are presented for two types of transfer problems, though the emphasis is on developing the methodology for solving the general problem.

How to Select a Questionnaire with a Good Methodological Quality?

PubMed

Paiva, Saul Martins; Perazzo, Matheus de França; Ortiz, Fernanda Ruffo; Pordeus, Isabela Almeida; Martins-Júnior, Paulo Antônio

2018-01-01

In the last decades, several instruments have been used to evaluate the impact of oral health problems on the oral health-related quality of life (OHRQoL) of individuals. However, some instruments lack thorough methodological validation or present conceptual differences that hinder comparisons with instruments. Thus, it can be difficult to clinicians and researchers to select a questionnaire that accurately reflect what are really meaningful to individuals. This short communication aimed to discuss the importance of use an appropriate checklist to select an instrument with a good methodological quality. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was developed to provide tools for evidence-based instrument selection. The COSMIN checklist comprises ten boxes that evaluate whether a study meets the standard for good methodological quality and two additional boxes to meet studies that use the Item Response Theory method and general requirements for results generalization, resulting in four steps to be followed. In this way, it is required at least some expertise in psychometrics or clinimetrics to a wide-ranging use of this checklist. The COSMIN applications include its use to ensure the standardization of cross-cultural adaptations and safer comparisons between measurement studies and evaluation of methodological quality of systematic reviews of measurement properties. Also, it can be used by students when training about measurement properties and by editors and reviewers when revising manuscripts on this topic. The popularization of COSMIN checklist is therefore necessary to improve the selection and evaluation of health measurement instruments.

Wrinkle-free design of thin membrane structures using stress-based topology optimization

NASA Astrophysics Data System (ADS)

Luo, Yangjun; Xing, Jian; Niu, Yanzhuang; Li, Ming; Kang, Zhan

2017-05-01

Thin membrane structures would experience wrinkling due to local buckling deformation when compressive stresses are induced in some regions. Using the stress criterion for membranes in wrinkled and taut states, this paper proposed a new stress-based topology optimization methodology to seek the optimal wrinkle-free design of macro-scale thin membrane structures under stretching. Based on the continuum model and linearly elastic assumption in the taut state, the optimization problem is defined as to maximize the structural stiffness under membrane area and principal stress constraints. In order to make the problem computationally tractable, the stress constraints are reformulated into equivalent ones and relaxed by a cosine-type relaxation scheme. The reformulated optimization problem is solved by a standard gradient-based algorithm with the adjoint-variable sensitivity analysis. Several examples with post-bulking simulations and experimental tests are given to demonstrate the effectiveness of the proposed optimization model for eliminating stress-related wrinkles in the novel design of thin membrane structures.

Sexual behavior and its correlates after traumatic brain injury.

PubMed

Turner, Daniel; Schöttle, Daniel; Krueger, Richard; Briken, Peer

2015-03-01

Traumatic brain injury (TBI) is one of the leading causes of permanent disability in young adults and is frequently accompanied by changes in sexual behaviors. Satisfying sexuality is an important factor for overall quality of life in people with disabilities. The purpose of this article is to review the studies evaluating the assessment, correlates and management of sexuality following TBI. The Brain Injury Questionnaire of Sexuality is the first validated questionnaire specifically developed for adults with TBI. A considerable amount of individuals with TBI show inappropriate sexual behaviors and sexual dysfunctions. Whereas inappropriate sexual behaviors are related to younger age, less social participation and more severe injuries, sexual dysfunctions show an association with higher fatigue, higher depression scores, less self-esteem and female sex. Healthcare professionals have suggested that because of discomfort at the individual or institutional level, sexual problems are often not sufficiently addressed and have suggested that a specialist should treat sexual problems. Although some important correlates of sexual problems could be identified, methodological differences across studies limit their comparability. Furthermore, there is an absence of evidence-based treatment strategies for addressing sexual problems. Therapeutic efforts should take into account the identified correlates of sexual problems following TBI.

A Scientific Approach to the Investigation on Anomalous Atmospheric Light Phenomena

NASA Astrophysics Data System (ADS)

Teodorani, M.

2011-12-01

Anomalous atmospheric light phenomena tend to occur recurrently in several places of our planet. Statistical studies show that a phenomenon's real recurrence area can be identified only after pondering reported cases on the population number and on the diffusion of communication media. The main scientific results that have been obtained so far after explorative instrumented missions have been carried out are presented, including the empirical models that have been set up in order to describe the observed reality. Subsequently, a focused theorization is discussed in order to attack the physical problem concerning the structure and the dynamics of "light balls" and the enigma related to the central force that maintains them in spherical shape. Finally, several important issues are discussed regarding methodology, strategy, tactics and interdisciplinary approaches.

Application of the boundary element method to the micromechanical analysis of composite materials

NASA Technical Reports Server (NTRS)

Goldberg, R. K.; Hopkins, D. A.

1995-01-01

A new boundary element formulation for the micromechanical analysis of composite materials is presented in this study. A unique feature of the formulation is the use of circular shape functions to convert the two-dimensional integrations of the composite fibers to one-dimensional integrations. To demonstrate the applicability of the formulations, several example problems including elastic and thermal analysis of laminated composites and elastic analyses of woven composites are presented and the boundary element results compared to experimental observations and/or results obtained through alternate analytical procedures. While several issues remain to be addressed in order to make the methodology more robust, the formulations presented here show the potential in providing an alternative to traditional finite element methods, particularly for complex composite architectures.

Transport mechanisms in Schottky diodes realized on GaN

NASA Astrophysics Data System (ADS)

Amor, Sarrah; Ahaitouf, Ali; Ahaitouf, Abdelaziz; Salvestrini, Jean Paul; Ougazzaden, Abdellah

2017-03-01

This work is focused on the conducted transport mechanisms involved on devices based in gallium nitride GaN and its alloys. With considering all conduction mechanisms of current, its possible to understanded these transport phenomena. Thanks to this methodology the current-voltage characteristics of structures with unusual behaviour are further understood and explain. Actually, the barrier height (SBH) is a complex problem since it depends on several parameters like the quality of the metal-semiconductor interface. This study is particularly interesting as solar cells are made on this material and their qualification is closely linked to their transport properties.

The application of remote sensing to resource management and environmental quality programs in Kansas

NASA Technical Reports Server (NTRS)

Barr, B. G.; Martinko, E. A.

1976-01-01

Activities of the Kansas Applied Remote Sensing Program (KARS) designed to establish interactions on cooperative projects with decision makers in Kansas agencies in the development and application of remote sensing procedures are reported. Cooperative demonstration projects undertaken with several different agencies involved three principal areas of effort: Wildlife Habitat and Environmental Analysis; Urban and Regional Analysis; Agricultural and Rural Analysis. These projects were designed to concentrate remote sensing concepts and methodologies on existing agency problems to insure the continued relevancy of the program and maximize the possibility for immediate operational use. Completed projects are briefly discussed.

Studies on young child malnutrition in Iraq: problems and insights, 1990-1999.

PubMed

Garfield, R

2000-09-01

Many reports on Iraq proclaimed a rise in rates of death and disease since the Gulf War of January/February 1991. Several of the studies on nutritional status are not readily accessible, and few have been compared to identify secular trends. Here, 27 studies examining nutrition among Iraqi children in the 1990s are reviewed. Only five studies were found to be of comparable methodologic quality. These are analyzed to identify major trends in child nutrition between August 1991 and June 1999. Limitations of existing studies and recommendations for future studies are discussed.

On the detection of pornographic digital images

NASA Astrophysics Data System (ADS)

Schettini, Raimondo; Brambilla, Carla; Cusano, Claudio; Ciocca, Gianluigi

2003-06-01

The paper addresses the problem of distinguishing between pornographic and non-pornographic photographs, for the design of semantic filters for the web. Both, decision forests of trees built according to CART (Classification And Regression Trees) methodology and Support Vectors Machines (SVM), have been used to perform the classification. The photographs are described by a set of low-level features, features that can be automatically computed simply on gray-level and color representation of the image. The database used in our experiments contained 1500 photographs, 750 of which labeled as pornographic on the basis of the independent judgement of several viewers.

[Methodological problems in the scientific research on HIV /AIDS in Bolivia].

PubMed

Hita, Susana Ramírez

2013-05-01

This paper discusses the methodological problems in the scientific research on HIV/AIDS in Bolivia, both in the areas of epidemiology and social sciences. Studies associated with this research served as the basis for the implementation of health programs run by The Global Fund, The Pan-American Health Organization, International Cooperation, Non-Governmental Organizations and the Bolivian Ministry of Health and Sports. An analysis of the methodological contradictions and weaknesses was made by reviewing the bibliography of the studies and by conducting qualitative methodological research, that was focused on the quality of health care available to people living with HIV/AIDS in public hospitals and health centers, and looked at how programs targeted at this sector of the population are designed and delivered. In this manner, it was possible to observe the shortcomings of the methodological design in the epidemiological and social science studies which serve as the basis for the implementation of these health programs.

Estimating prevalence and burden of major disorders of the brain in Nepal: cultural, geographic, logistic and philosophical issues of methodology.

PubMed

Risal, Ajay; Manandhar, Kedar; Steiner, Timothy J; Holen, Are; Koju, Rajendra; Linde, Mattias

2014-08-15

Headache, anxiety and depression are major disorders of the brain in terms of their prevalence and the burdens and costs they impose on society. Nationwide population-based studies of these disorders are necessary to inform health policy but, in research-naïve and resource-poor countries such as Nepal, a host of methodological problems are encountered: cultural, geographic, logistic and philosophical. Expert consensus was sought among researchers from different professional and cultural backgrounds in planning and conceptualizing an epidemiological study and adapting established methods to the special situation and circumstances of Nepal. The methodological problems were sorted into different themes: study design; climate; geography, access and transport; sociocultural issues; safety of interviewers. Each of these was dealt with separately, and their inter-relationships explored, in finding solutions that were sometimes pragmatic. A cross-sectional questionnaire-based study, with teams of interviewers visiting households across the three physiographic divisions (with extremes in altitude) in each of the five development regions of the country, would enable national sampling with sociocultural representativeness. However, the study instruments and interviews would be in Nepali only. Transport and access challenges were considerable, and their solutions combined travel by air, bus, river and foot, with allowances for rain-damaged roads, collapsed bridges and cancelled scheduled flights. The monsoon would render many routes impassable, and therefore set an absolute time limitation. Engaging participants willingly in the enquiry would be the key to success, and several tactics would be employed to enhance the success of this, most importantly enlisting the support of local community volunteers in each study site. Anticipating problems in advance of investing substantial resources in a large nationwide epidemiological study in Nepal was a sensible precaution. The difficulties could be resolved or circumvented without expected compromise in scientific quality. Expert consensus was an effective means of achieving this outcome.

Effective strategies to motivate nursing home residents in oral care and to prevent or reduce responsive behaviors to oral care: A systematic review

PubMed Central

Kent, Angelle; Kobagi, Nadia; Huynh, Kha Tu; Clarke, Alix; Yoon, Minn N.

2017-01-01

Background Poor oral health has been a persistent problem in nursing home residents for decades, with severe consequences for residents and the health care system. Two major barriers to providing appropriate oral care are residents’ responsive behaviors to oral care and residents’ lack of ability or motivation to perform oral care on their own. Objectives To evaluate the effectiveness of strategies that nursing home care providers can apply to either prevent/overcome residents’ responsive behaviors to oral care, or enable/motivate residents to perform their own oral care. Materials and methods We searched the databases Medline, EMBASE, Evidence Based Reviews–Cochrane Central Register of Controlled Trials, CINAHL, and Web of Science for intervention studies assessing the effectiveness of eligible strategies. Two reviewers independently (a) screened titles, abstracts and retrieved full-texts; (b) searched key journal contents, key author publications, and reference lists of all included studies; and (c) assessed methodological quality of included studies. Discrepancies at any stage were resolved by consensus. We conducted a narrative synthesis of study results. Results We included three one-group pre-test, post-test studies, and one cross-sectional study. Methodological quality was low (n = 3) and low moderate (n = 1). Two studies assessed strategies to enable/motivate nursing home residents to perform their own oral care, and to studies assessed strategies to prevent or overcome responsive behaviors to oral care. All studies reported improvements of at least some of the outcomes measured, but interpretation is limited due to methodological problems. Conclusions Potentially promising strategies are available that nursing home care providers can apply to prevent/overcome residents’ responsive behaviors to oral care or to enable/motivate residents to perform their own oral care. However, studies assessing these strategies have a high risk for bias. To overcome oral health problems in nursing homes, care providers will need practical strategies whose effectiveness was assessed in robust studies. PMID:28609476

Estimating prevalence and burden of major disorders of the brain in Nepal: cultural, geographic, logistic and philosophical issues of methodology

PubMed Central

2014-01-01

Background Headache, anxiety and depression are major disorders of the brain in terms of their prevalence and the burdens and costs they impose on society. Nationwide population-based studies of these disorders are necessary to inform health policy but, in research-naïve and resource-poor countries such as Nepal, a host of methodological problems are encountered: cultural, geographic, logistic and philosophical. Methods Expert consensus was sought among researchers from different professional and cultural backgrounds in planning and conceptualizing an epidemiological study and adapting established methods to the special situation and circumstances of Nepal. Results The methodological problems were sorted into different themes: study design; climate; geography, access and transport; sociocultural issues; safety of interviewers. Each of these was dealt with separately, and their inter-relationships explored, in finding solutions that were sometimes pragmatic. A cross-sectional questionnaire-based study, with teams of interviewers visiting households across the three physiographic divisions (with extremes in altitude) in each of the five development regions of the country, would enable national sampling with sociocultural representativeness. However, the study instruments and interviews would be in Nepali only. Transport and access challenges were considerable, and their solutions combined travel by air, bus, river and foot, with allowances for rain-damaged roads, collapsed bridges and cancelled scheduled flights. The monsoon would render many routes impassable, and therefore set an absolute time limitation. Engaging participants willingly in the enquiry would be the key to success, and several tactics would be employed to enhance the success of this, most importantly enlisting the support of local community volunteers in each study site. Conclusion Anticipating problems in advance of investing substantial resources in a large nationwide epidemiological study in Nepal was a sensible precaution. The difficulties could be resolved or circumvented without expected compromise in scientific quality. Expert consensus was an effective means of achieving this outcome. PMID:25127664

Rapid Design of Gravity Assist Trajectories

NASA Technical Reports Server (NTRS)

Carrico, J.; Hooper, H. L.; Roszman, L.; Gramling, C.

1991-01-01

Several International Solar Terrestrial Physics (ISTP) missions require the design of complex gravity assisted trajectories in order to investigate the interaction of the solar wind with the Earth's magnetic field. These trajectories present a formidable trajectory design and optimization problem. The philosophy and methodology that enable an analyst to design and analyse such trajectories are discussed. The so called 'floating end point' targeting, which allows the inherently nonlinear multiple body problem to be solved with simple linear techniques, is described. The combination of floating end point targeting with analytic approximations with a Newton method targeter to achieve trajectory design goals quickly, even for the very sensitive double lunar swingby trajectories used by the ISTP missions, is demonstrated. A multiconic orbit integration scheme allows fast and accurate orbit propagation. A prototype software tool, Swingby, built for trajectory design and launch window analysis, is described.

Usage-Centered Design Approach in Design of Malaysia Sexuality Education (MSE) Courseware

NASA Astrophysics Data System (ADS)

Chan, S. L.; Jaafar, A.

The problems amongst juveniles increased every year, especially rape case of minor. Therefore, the government of Malaysia has introduced the National Sexuality Education Guideline on 2005. An early study related to the perception of teachers and students toward the sexuality education curriculum taught in secondary schools currently was carried out in 2008. The study showed that there are big gaps between the perception of the teachers and the students towards several issues of Malaysia sexuality education today. The Malaysia Sexuality Education (MSE) courseware was designed based on few learning theories approach. Then MSE was executed through a comprehensive methodology which the model ADDIE integrated with Usage-Centered Design to achieve high usability courseware. In conclusion, the effort of developing the MSE is hopefully will be a solution to the current problem that happens in Malaysia sexuality education now.

Algorithm based on the Thomson problem for determination of equilibrium structures of metal nanoclusters

NASA Astrophysics Data System (ADS)

Arias, E.; Florez, E.; Pérez-Torres, J. F.

2017-06-01

A new algorithm for the determination of equilibrium structures suitable for metal nanoclusters is proposed. The algorithm performs a stochastic search of the minima associated with the nuclear potential energy function restricted to a sphere (similar to the Thomson problem), in order to guess configurations of the nuclear positions. Subsequently, the guessed configurations are further optimized driven by the total energy function using the conventional gradient descent method. This methodology is equivalent to using the valence shell electron pair repulsion model in guessing initial configurations in the traditional molecular quantum chemistry. The framework is illustrated in several clusters of increasing complexity: Cu7, Cu9, and Cu11 as benchmark systems, and Cu38 and Ni9 as novel systems. New equilibrium structures for Cu9, Cu11, Cu38, and Ni9 are reported.

Mining the preferences of patients for ubiquitous clinic recommendation.

PubMed

Chen, Tin-Chih Toly; Chiu, Min-Chi

2018-03-06

A challenge facing all ubiquitous clinic recommendation systems is that patients often have difficulty articulating their requirements. To overcome this problem, a ubiquitous clinic recommendation mechanism was designed in this study by mining the clinic preferences of patients. Their preferences were defined using the weights in the ubiquitous clinic recommendation mechanism. An integer nonlinear programming problem was solved to tune the values of the weights on a rolling basis. In addition, since it may take a long time to adjust the values of weights to their asymptotic values, the back propagation network (BPN)-response surface method (RSM) method is applied to estimate the asymptotic values of weights. The proposed methodology was tested in a regional study. Experimental results indicated that the ubiquitous clinic recommendation system outperformed several existing methods in improving the successful recommendation rate.

Algorithm based on the Thomson problem for determination of equilibrium structures of metal nanoclusters.

PubMed

Arias, E; Florez, E; Pérez-Torres, J F

2017-06-28

A new algorithm for the determination of equilibrium structures suitable for metal nanoclusters is proposed. The algorithm performs a stochastic search of the minima associated with the nuclear potential energy function restricted to a sphere (similar to the Thomson problem), in order to guess configurations of the nuclear positions. Subsequently, the guessed configurations are further optimized driven by the total energy function using the conventional gradient descent method. This methodology is equivalent to using the valence shell electron pair repulsion model in guessing initial configurations in the traditional molecular quantum chemistry. The framework is illustrated in several clusters of increasing complexity: Cu 7 , Cu 9 , and Cu 11 as benchmark systems, and Cu 38 and Ni 9 as novel systems. New equilibrium structures for Cu 9 , Cu 11 , Cu 38 , and Ni 9 are reported.

Methodological problems in the neuropsychological assessment of effects of exposure to welding fumes and manganese.

PubMed

Lees-Haley, Paul R; Greiffenstein, M Frank; Larrabee, Glenn J; Manning, Edward L

2004-08-01

Recently, Kaiser (2003) raised concerns over the increase in brain damage claims reportedly due to exposure to welding fumes. In the present article, we discuss methodological problems in conducting neuropsychological research on the effects of welding exposure, using a recent paper by Bowler et al. (2003) as an example to illustrate problems common in the neurotoxicity literature. Our analysis highlights difficulties in conducting such quasi-experimental investigations, including subject selection bias, litigation effects on symptom report and neuropsychological test performance, response bias, and scientifically inadequate casual reasoning.

Design and Diagnosis Problem Solving with Multifunctional Technical Knowledge Bases

DTIC Science & Technology

1992-09-29

STRUCTURE METHODOLOGY Design problem solving is a complex activity involving a number of subtasks. and a number of alternative methods potentially available...Conference on Artificial Intelligence. London: The British Computer Society, pp. 621-633. Friedland, P. (1979). Knowledge-based experimental design ...Computing Milieuxl: Management of Computing and Information Systems- -ty,*m man- agement General Terms: Design . Methodology Additional Key Words and Phrases

Rapid Classification of Landsat TM Imagery for Phase 1 Stratification Using the Automated NDVI Threshold Supervised Classification (ANTSC) Methodology

Treesearch

William H. Cooke; Dennis M. Jacobs

2005-01-01

FIA annual inventories require rapid updating of pixel-based Phase 1 estimates. Scientists at the Southern Research Station are developing an automated methodology that uses a Normalized Difference Vegetation Index (NDVI) for identifying and eliminating problem FIA plots from the analysis. Problem plots are those that have questionable land use/land cover information....

A systematic review of health effects of electronic cigarettes.

PubMed

Pisinger, Charlotta; Døssing, Martin

2014-12-01

To provide a systematic review of the existing literature on health consequences of vaporing of electronic cigarettes (ECs). Search in: PubMed, EMBASE and CINAHL. Original publications describing a health-related topic, published before 14 August 2014. PRISMA recommendations were followed. We identified 1101 studies; 271 relevant after screening; 94 eligible. We included 76 studies investigating content of fluid/vapor of ECs, reports on adverse events and human and animal experimental studies. Serious methodological problems were identified. In 34% of the articles the authors had a conflict of interest. Studies found fine/ultrafine particles, harmful metals, carcinogenic tobacco-specific nitrosamines, volatile organic compounds, carcinogenic carbonyls (some in high but most in low/trace concentrations), cytotoxicity and changed gene expression. Of special concern are compounds not found in conventional cigarettes, e.g. propylene glycol. Experimental studies found increased airway resistance after short-term exposure. Reports on short-term adverse events were often flawed by selection bias. Due to many methodological problems, severe conflicts of interest, the relatively few and often small studies, the inconsistencies and contradictions in results, and the lack of long-term follow-up no firm conclusions can be drawn on the safety of ECs. However, they can hardly be considered harmless. Copyright © 2014. Published by Elsevier Inc.

Psychiatric aspects of induced abortion.

PubMed

Stotland, Nada L

2011-08-01

Approximately one third of the women in the United States have an abortion during their lives. In the year 2008, 1.21 million abortions were performed in the United States (Jones and Koolstra, Perspect Sex Reprod Health 43:41-50, 2011). The psychiatric outcomes of abortion are scientifically well established (Adler et al., Science 248:41-43, 1990). Despite assertions to the contrary, there is no evidence that abortion causes psychiatric problems (Dagg, Am J Psychiatry 148:578-585, 1991). Those studies that report psychiatric sequelae suffer from severe methodological defects (Lagakos, N Engl J Med 354:1667-1669, 2006). Methodologically sound studies have demonstrated that there is a very low incidence of frank psychiatric illness after an abortion; women experience a wide variety of feelings over time, including, for some, transient sadness and grieving. However, the circumstances that lead a woman to terminate a pregnancy, including previous and/or ongoing psychiatric illness, are independently stressful and increase the likelihood of psychiatric illness over the already high baseline incidence and prevalence of mood and anxiety disorders among women of childbearing age. For optimal psychological outcomes, women, including adolescents, need to make autonomous and supported decisions about problem pregnancies. Clinicians can help patients facing these decisions and those who are working through feelings about having had abortions in the past.

A new convergence analysis and perturbation resilience of some accelerated proximal forward-backward algorithms with errors

NASA Astrophysics Data System (ADS)

Reem, Daniel; De Pierro, Alvaro

2017-04-01

Many problems in science and engineering involve, as part of their solution process, the consideration of a separable function which is the sum of two convex functions, one of them possibly non-smooth. Recently a few works have discussed inexact versions of several accelerated proximal methods aiming at solving this minimization problem. This paper shows that inexact versions of a method of Beck and Teboulle (fast iterative shrinkable tresholding algorithm) preserve, in a Hilbert space setting, the same (non-asymptotic) rate of convergence under some assumptions on the decay rate of the error terms The notion of inexactness discussed here seems to be rather simple, but, interestingly, when comparing to related works, closely related decay rates of the errors terms yield closely related convergence rates. The derivation sheds some light on the somewhat mysterious origin of some parameters which appear in various accelerated methods. A consequence of the analysis is that the accelerated method is perturbation resilient, making it suitable, in principle, for the superiorization methodology. By taking this into account, we re-examine the superiorization methodology and significantly extend its scope. This work was supported by FAPESP 2013/19504-9. The second author was supported also by CNPq grant 306030/2014-4.

Lean Six Sigma: a new approach to the management of patients undergoing prosthetic hip replacement surgery.

PubMed

Improta, Giovanni; Balato, Giovanni; Romano, Maria; Carpentieri, Francesco; Bifulco, Paolo; Alessandro Russo, Mario; Rosa, Donato; Triassi, Maria; Cesarelli, Mario

2015-08-01

In 2012, health care spending in Italy reached €114.5 billion, accounting for 7.2% of the Gross Domestic Product (GDP) and 14.2% of total public spending. Therefore, reducing waste in health facilities could generate substantial cost savings. The objective of this study is to show that Lean Six Sigma represents an appropriate methodology for the development of a clinical pathway which allows to improve quality and to reduce costs in prosthetic hip replacement surgery. The methodology used for the development of a new clinical pathway was Lean Six Sigma. Problem solving in Lean Six Sigma is the DMAIC (Define, Measure, Analyse, Improve, Control) roadmap, characterized by five operational phases which make possible to reach fixed goals through a rigorous process of defining, measuring, analysing, improving and controlling business problems. The following project indicated several variables influencing the inappropriate prolongation of the length of stay for inpatient treatment and corrective actions were performed to improve the effectiveness and efficiency of the process of care. The average length of stay was reduced from 18.9 to 10.6 days (-44%). This article shows there is no trade-off between quality and costs: Lean Six Sigma improves quality and, at the same time, reduces costs. © 2015 John Wiley & Sons, Ltd.

Science and Television Commercials: Adding Relevance to the Research Methodology Course.

ERIC Educational Resources Information Center

Solomon, Paul R.

1979-01-01

Contends that research methodology courses can be relevant to issues outside of psychology and describes a method which relates the course to consumer problems. Students use experimental methodology to test claims made in television commercials advertising deodorant, bathroom tissues, and soft drinks. (KC)

Investigation of Nonlinear Pressurization and Model Restart in MSC/NASTRAN for Modeling Thin Film Inflatable Structures

NASA Technical Reports Server (NTRS)

Smalley, Kurt B.; Tinker, Michael L.; Fischer, Richard T.

2001-01-01

This paper is written for the purpose of providing an introduction and set of guidelines for the use of a methodology for NASTRAN eigenvalue modeling of thin film inflatable structures. It is hoped that this paper will spare the reader from the problems and headaches the authors were confronted with during their investigation by presenting here not only an introduction and verification of the methodology, but also a discussion of the problems that this methodology can ensue. Our goal in this investigation was to verify the basic methodology through the creation and correlation of a simple model. An overview of thin film structures, their history, and their applications is given. Previous modeling work is then briefly discussed. An introduction is then given for the method of modeling. The specific mechanics of the method are then discussed in parallel with a basic discussion of NASTRAN s implementation of these mechanics. The problems encountered with the method are then given along with suggestions for their work-a-rounds. The methodology is verified through the correlation between an analytical model and modal test results of a thin film strut. Recommendations are given for the needed advancement of our understanding of this method and ability to accurately model thin film structures. Finally, conclusions are drawn regarding the usefulness of the methodology.

Multilevel Methodology for Simulation of Spatio-Temporal Systems with Heterogeneous Activity; Application to Spread of Valley Fever Fungus

USGS Publications Warehouse

Jammalamadaka, Rajanikanth

2009-01-01

This report consists of a dissertation submitted to the faculty of the Department of Electrical and Computer Engineering, in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Graduate College, The University of Arizona, 2008. Spatio-temporal systems with heterogeneity in their structure and behavior have two major problems associated with them. The first one is that such complex real world systems extend over very large spatial and temporal domains and consume so many computational resources to simulate that they are infeasible to study with current computational platforms. The second one is that the data available for understanding such systems is limited because they are spread over space and time making it hard to obtain micro and macro measurements. This also makes it difficult to get the data for validation of their constituent processes while simultaneously considering their global behavior. For example, the valley fever fungus considered in this dissertation is spread over a large spatial grid in the arid Southwest and typically needs to be simulated over several decades of time to obtain useful information. It is also hard to get the temperature and moisture data (which are two critical factors on which the survival of the valley fever fungus depends) at every grid point of the spatial domain over the region of study. In order to address the first problem, we develop a method based on the discrete event system specification which exploits the heterogeneity in the activity of the spatio-temporal system and which has been shown to be effective in solving relatively simple partial differential equation systems. The benefit of addressing the first problem is that it now makes it feasible to address the second problem. We address the second problem by making use of a multilevel methodology based on modeling and simulation and systems theory. This methodology helps us in the construction of models with different resolutions (base and lumped models). This allows us to refine an initially constructed lumped model with detailed physics-based process models and assess whether they improve on the original lumped models. For that assessment, we use the concept of experimental frame to delimit where the improvement is needed. This allows us to work with the available data, improve the component models in their own experimental frame and then move them to the overall frame. In this dissertation, we develop a multilevel methodology and apply it to a valley fever model. Moreover, we study the model's behavior in a particular experimental frame of interest, namely the formation of new sporing sites.

[Development of New Mathematical Methodology in Air Traffic Control for the Analysis of Hybrid Systems

NASA Technical Reports Server (NTRS)

Hermann, Robert

1997-01-01

The aim of this research is to develop new mathematical methodology for the analysis of hybrid systems of the type involved in Air Traffic Control (ATC) problems. Two directions of investigation were initiated. The first used the methodology of nonlinear generalized functions, whose mathematical foundations were initiated by Colombeau and developed further by Oberguggenberger; it has been extended to apply to ordinary differential. Systems of the type encountered in control in joint work with the PI and M. Oberguggenberger. This involved a 'mixture' of 'continuous' and 'discrete' methodology. ATC clearly involves mixtures of two sorts of mathematical problems: (1) The 'continuous' dynamics of a standard control type described by ordinary differential equations (ODE) of the form: {dx/dt = f(x, u)} and (2) the discrete lattice dynamics involved of cellular automata. Most of the CA literature involves a discretization of a partial differential equation system of the type encountered in physics problems (e.g. fluid and gas problems). Both of these directions requires much thinking and new development of mathematical fundamentals before they may be utilized in the ATC work. Rather than consider CA as 'discretization' of PDE systems, I believe that the ATC applications will require a completely different and new mathematical methodology, a sort of discrete analogue of jet bundles and/or the sheaf-theoretic techniques to topologists. Here too, I have begun work on virtually 'virgin' mathematical ground (at least from an 'applied' point of view) which will require considerable preliminary work.

Intelligent systems engineering methodology

NASA Technical Reports Server (NTRS)

Fouse, Scott

1990-01-01

An added challenge for the designers of large scale systems such as Space Station Freedom is the appropriate incorporation of intelligent system technology (artificial intelligence, expert systems, knowledge-based systems, etc.) into their requirements and design. This presentation will describe a view of systems engineering which successfully addresses several aspects of this complex problem: design of large scale systems, design with requirements that are so complex they only completely unfold during the development of a baseline system and even then continue to evolve throughout the system's life cycle, design that involves the incorporation of new technologies, and design and development that takes place with many players in a distributed manner yet can be easily integrated to meet a single view of the requirements. The first generation of this methodology was developed and evolved jointly by ISX and the Lockheed Aeronautical Systems Company over the past five years on the Defense Advanced Research Projects Agency/Air Force Pilot's Associate Program, one of the largest, most complex, and most successful intelligent systems constructed to date. As the methodology has evolved it has also been applied successfully to a number of other projects. Some of the lessons learned from this experience may be applicable to Freedom.

Model-Based Thermal System Design Optimization for the James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Cataldo, Giuseppe; Niedner, Malcolm B.; Fixsen, Dale J.; Moseley, Samuel H.

2017-01-01

Spacecraft thermal model validation is normally performed by comparing model predictions with thermal test data and reducing their discrepancies to meet the mission requirements. Based on thermal engineering expertise, the model input parameters are adjusted to tune the model output response to the test data. The end result is not guaranteed to be the best solution in terms of reduced discrepancy and the process requires months to complete. A model-based methodology was developed to perform the validation process in a fully automated fashion and provide mathematical bases to the search for the optimal parameter set that minimizes the discrepancies between model and data. The methodology was successfully applied to several thermal subsystems of the James Webb Space Telescope (JWST). Global or quasiglobal optimal solutions were found and the total execution time of the model validation process was reduced to about two weeks. The model sensitivities to the parameters, which are required to solve the optimization problem, can be calculated automatically before the test begins and provide a library for sensitivity studies. This methodology represents a crucial commodity when testing complex, large-scale systems under time and budget constraints. Here, results for the JWST Core thermal system will be presented in detail.

Scalable tuning of building models to hourly data

DOE PAGES

Garrett, Aaron; New, Joshua Ryan

2015-03-31

Energy models of existing buildings are unreliable unless calibrated so they correlate well with actual energy usage. Manual tuning requires a skilled professional, is prohibitively expensive for small projects, imperfect, non-repeatable, non-transferable, and not scalable to the dozens of sensor channels that smart meters, smart appliances, and cheap/ubiquitous sensors are beginning to make available today. A scalable, automated methodology is needed to quickly and intelligently calibrate building energy models to all available data, increase the usefulness of those models, and facilitate speed-and-scale penetration of simulation-based capabilities into the marketplace for actualized energy savings. The "Autotune'' project is a novel, model-agnosticmore » methodology which leverages supercomputing, large simulation ensembles, and big data mining with multiple machine learning algorithms to allow automatic calibration of simulations that match measured experimental data in a way that is deployable on commodity hardware. This paper shares several methodologies employed to reduce the combinatorial complexity to a computationally tractable search problem for hundreds of input parameters. Furthermore, accuracy metrics are provided which quantify model error to measured data for either monthly or hourly electrical usage from a highly-instrumented, emulated-occupancy research home.« less

Model-based thermal system design optimization for the James Webb Space Telescope

NASA Astrophysics Data System (ADS)

Cataldo, Giuseppe; Niedner, Malcolm B.; Fixsen, Dale J.; Moseley, Samuel H.

2017-10-01

Spacecraft thermal model validation is normally performed by comparing model predictions with thermal test data and reducing their discrepancies to meet the mission requirements. Based on thermal engineering expertise, the model input parameters are adjusted to tune the model output response to the test data. The end result is not guaranteed to be the best solution in terms of reduced discrepancy and the process requires months to complete. A model-based methodology was developed to perform the validation process in a fully automated fashion and provide mathematical bases to the search for the optimal parameter set that minimizes the discrepancies between model and data. The methodology was successfully applied to several thermal subsystems of the James Webb Space Telescope (JWST). Global or quasiglobal optimal solutions were found and the total execution time of the model validation process was reduced to about two weeks. The model sensitivities to the parameters, which are required to solve the optimization problem, can be calculated automatically before the test begins and provide a library for sensitivity studies. This methodology represents a crucial commodity when testing complex, large-scale systems under time and budget constraints. Here, results for the JWST Core thermal system will be presented in detail.

Extending injury prevention methodology to chemical terrorism preparedness: the Haddon Matrix and sarin.

PubMed

Varney, Shawn; Hirshon, Jon Mark; Dischinger, Patricia; Mackenzie, Colin

2006-01-01

The Haddon Matrix offers a classic epidemiological model for studying injury prevention. This methodology places the public health concepts of agent, host, and environment within the three sequential phases of an injury-producing incident-pre-event, event, and postevent. This study uses this methodology to illustrate how it could be applied in systematically preparing for a mass casualty disaster such as an unconventional sarin attack in a major urban setting. Nineteen city, state, federal, and military agencies responded to the Haddon Matrix chemical terrorism preparedness exercise and offered feedback in the data review session. Four injury prevention strategies (education, engineering, enforcement, and economics) were applied to the individual factors and event phases of the Haddon Matrix. The majority of factors identified in all phases were modifiable, primarily through educational interventions focused on individual healthcare providers and first responders. The Haddon Matrix provides a viable means of studying an unconventional problem, allowing for the identification of modifiable factors to decrease the type and severity of injuries following a mass casualty disaster such as a sarin release. This strategy could be successfully incorporated into disaster planning for other weapons attacks that could potentially cause mass casualties.

Detecting and correcting for publication bias in meta-analysis - A truncated normal distribution approach.

PubMed

Zhu, Qiaohao; Carriere, K C

2016-01-01

Publication bias can significantly limit the validity of meta-analysis when trying to draw conclusion about a research question from independent studies. Most research on detection and correction for publication bias in meta-analysis focus mainly on funnel plot-based methodologies or selection models. In this paper, we formulate publication bias as a truncated distribution problem, and propose new parametric solutions. We develop methodologies of estimating the underlying overall effect size and the severity of publication bias. We distinguish the two major situations, in which publication bias may be induced by: (1) small effect size or (2) large p-value. We consider both fixed and random effects models, and derive estimators for the overall mean and the truncation proportion. These estimators will be obtained using maximum likelihood estimation and method of moments under fixed- and random-effects models, respectively. We carried out extensive simulation studies to evaluate the performance of our methodology, and to compare with the non-parametric Trim and Fill method based on funnel plot. We find that our methods based on truncated normal distribution perform consistently well, both in detecting and correcting publication bias under various situations.

Financial Support for the Humanities: A Special Methodological Report.

ERIC Educational Resources Information Center

Gomberg, Irene L.; Atelsek, Frank J.

Findings and methodological problems of a survey on financial support for humanities in higher education are discussed. Usable data were gathered from 351 of 671 Higher Education Panel member institutions. Two weighting methodologies were employed. The conventional method assumed that nonrespondents were similar to respondents, whereas a…

An automated methodology development. [software design for combat simulation

NASA Technical Reports Server (NTRS)

Hawley, L. R.

1985-01-01

The design methodology employed in testing the applicability of Ada in large-scale combat simulations is described. Ada was considered as a substitute for FORTRAN to lower life cycle costs and ease the program development efforts. An object-oriented approach was taken, which featured definitions of military targets, the capability of manipulating their condition in real-time, and one-to-one correlation between the object states and real world states. The simulation design process was automated by the problem statement language (PSL)/problem statement analyzer (PSA). The PSL/PSA system accessed the problem data base directly to enhance the code efficiency by, e.g., eliminating non-used subroutines, and provided for automated report generation, besides allowing for functional and interface descriptions. The ways in which the methodology satisfied the responsiveness, reliability, transportability, modifiability, timeliness and efficiency goals are discussed.

Technology transfer methodology

NASA Technical Reports Server (NTRS)

Labotz, Rich

1991-01-01

Information on technology transfer methodology is given in viewgraph form. Topics covered include problems in economics, technology drivers, inhibitors to using improved technology in development, technology application opportunities, and co-sponsorship of technology.

Engineering tradeoff problems viewed as multiple objective optimizations and the VODCA methodology

NASA Astrophysics Data System (ADS)

Morgan, T. W.; Thurgood, R. L.

1984-05-01

This paper summarizes a rational model for making engineering tradeoff decisions. The model is a hybrid from the fields of social welfare economics, communications, and operations research. A solution methodology (Vector Optimization Decision Convergence Algorithm - VODCA) firmly grounded in the economic model is developed both conceptually and mathematically. The primary objective for developing the VODCA methodology was to improve the process for extracting relative value information about the objectives from the appropriate decision makers. This objective was accomplished by employing data filtering techniques to increase the consistency of the relative value information and decrease the amount of information required. VODCA is applied to a simplified hypothetical tradeoff decision problem. Possible use of multiple objective analysis concepts and the VODCA methodology in product-line development and market research are discussed.

A modular inverse elastostatics approach to resolve the pressure-induced stress state for in vivo imaging based cardiovascular modeling.

PubMed

Peirlinck, Mathias; De Beule, Matthieu; Segers, Patrick; Rebelo, Nuno

2018-05-28

Patient-specific biomechanical modeling of the cardiovascular system is complicated by the presence of a physiological pressure load given that the imaged tissue is in a pre-stressed and -strained state. Neglect of this prestressed state into solid tissue mechanics models leads to erroneous metrics (e.g. wall deformation, peak stress, wall shear stress) which in their turn are used for device design choices, risk assessment (e.g. procedure, rupture) and surgery planning. It is thus of utmost importance to incorporate this deformed and loaded tissue state into the computational models, which implies solving an inverse problem (calculating an undeformed geometry given the load and the deformed geometry). Methodologies to solve this inverse problem can be categorized into iterative and direct methodologies, both having their inherent advantages and disadvantages. Direct methodologies are typically based on the inverse elastostatics (IE) approach and offer a computationally efficient single shot methodology to compute the in vivo stress state. However, cumbersome and problem-specific derivations of the formulations and non-trivial access to the finite element analysis (FEA) code, especially for commercial products, refrain a broad implementation of these methodologies. For that reason, we developed a novel, modular IE approach and implemented this methodology in a commercial FEA solver with minor user subroutine interventions. The accuracy of this methodology was demonstrated in an arterial tube and porcine biventricular myocardium model. The computational power and efficiency of the methodology was shown by computing the in vivo stress and strain state, and the corresponding unloaded geometry, for two models containing multiple interacting incompressible, anisotropic (fiber-embedded) and hyperelastic material behaviors: a patient-specific abdominal aortic aneurysm and a full 4-chamber heart model. Copyright © 2018 Elsevier Ltd. All rights reserved.

Varieties of second modernity: the cosmopolitan turn in social and political theory and research.

PubMed

Beck, Ulrich; Grande, Edgar

2010-09-01

The theme of this special issue is the necessity of a cosmopolitan turn in social and political theory. The question at the heart of this introductory chapter takes the challenge of 'methodological cosmopolitanism', already addressed in a Special Issue on Cosmopolitan Sociology in this journal (Beck and Sznaider 2006), an important step further: How can social and political theory be opened up, theoretically as well as methodologically and normatively, to a historically new, entangled Modernity which threatens its own foundations? How can it account for the fundamental fragility, the mutability of societal dynamics (of unintended side effects, domination and power), shaped by the globalization of capital and risks at the beginning of the twenty-first century? What theoretical and methodological problems arise and how can they be addressed in empirical research? In the following, we will develop this 'cosmopolitan turn' in four steps: firstly, we present the major conceptual tools for a theory of cosmopolitan modernities; secondly, we de-construct Western modernity by using examples taken from research on individualization and risk; thirdly, we address the key problem of methodological cosmopolitanism, namely the problem of defining the appropriate unit of analysis; and finally,we discuss normative questions, perspectives, and dilemmas of a theory of cosmopolitan modernities, in particular problems of political agency and prospects of political realization.

A Bayesian approach to truncated data sets: An application to Malmquist bias in Supernova Cosmology

NASA Astrophysics Data System (ADS)

March, Marisa Cristina

2018-01-01

A problem commonly encountered in statistical analysis of data is that of truncated data sets. A truncated data set is one in which a number of data points are completely missing from a sample, this is in contrast to a censored sample in which partial information is missing from some data points. In astrophysics this problem is commonly seen in a magnitude limited survey such that the survey is incomplete at fainter magnitudes, that is, certain faint objects are simply not observed. The effect of this `missing data' is manifested as Malmquist bias and can result in biases in parameter inference if it is not accounted for. In Frequentist methodologies the Malmquist bias is often corrected for by analysing many simulations and computing the appropriate correction factors. One problem with this methodology is that the corrections are model dependent. In this poster we derive a Bayesian methodology for accounting for truncated data sets in problems of parameter inference and model selection. We first show the methodology for a simple Gaussian linear model and then go on to show the method for accounting for a truncated data set in the case for cosmological parameter inference with a magnitude limited supernova Ia survey.

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

Kaminsky, J.; Tschanz, J.F.

In order to adress barriers to community energy-conservation efforts, DOE has established the Comprehensive Community Energy Management (CCEM) program. The role of CCEM is to provide direction and technical support for energy-conservation efforts at the local level. The program to date has included project efforts to develop combinations and variations of community energy planning and management tools applicable to communities of diverse characteristics. This paper describes the salient features of some of the tools and relates them to the testing program soon to begin in several pilot-study communities. Two methodologies that arose within such an actual planning context are takenmore » from DOE-sponsored projects in Clarksburg, West Virginia and the proposed new capital city for Alaska. Energy management in smaller communities and/or communities with limited funding and manpower resources has received special attention. One project of this type developed in general methodology that emphasizes efficient ways for small communities to reach agreement on local energy problems and potential solutions; by this guidance, the community is led to understand where it should concentrate its efforts in subsequent management activities. Another project concerns rapid growth of either a new or an existing community that could easily outstrip the management resources available locally. This methodology strives to enable the community to seize the opportunity for energy conservation through integrating the design of its energy systems and its development pattern. The last methodology creates applicable tools for comprehensive community energy planning. (MCW)« less

The solution of the problem of oil spill risk control in the Baltic Sea taking into account the processes of oil propagation and degradation

NASA Astrophysics Data System (ADS)

Aseev, Nikita; Agoshkov, Valery

2015-04-01

The report is devoted to the one approach to the problem of oil spill risk control of protected areas in the Baltic Sea (Aseev et al., 2014). By the problem of risk control is meant a problem of determination of optimal resources quantity which are necessary for decreasing the risk to some acceptable value. It is supposed that only moment of accident is a random variable. Mass of oil slick is chosen as a function of control. For the realization of the random variable the quadratic 'functional of cost' is introduced. It comprises cleaning costs and deviation of damage of oil pollution from its acceptable value. The problem of minimization of this functional is solved based on the methods of optimal control and the theory of adjoint equations (Agoshkov, 2003, Agoshkov et al., 2012). The solution of this problem is explicitly found. In order to solve the realistic problem of oil spill risk control in the Baltic Sea the 2d model of oil spill propagation on the sea surface based on the Seatrack Web model (Liungman, Mattson, 2011) is developed. The model takes into account such processes as oil transportation by sea currents and wind, turbulent diffusion, spreading, evaporation from sea surface, dispersion and formation of emulsion 'water-in-oil'. The model allows to calculate basic oil slick parameters: localization, mass, volume, thickness, density of oil, water content and viscosity of emulsion. The results of several numerical experiments in the Baltic Sea using the model and the methodology of oil spill risk control are presented. Along with moment of accident other parameters of oil spill and environment could be chosen as a random variables. The methodology of solution of oil spill risk control problem will remain the same but the computational complexity will increase. Conversion of the function of control to quantity of resources with a glance to methods of pollution removal should be processed. As a result, the developed 2d model of oil spill propagation combined with the methodology of solution of oil spill risk control problem could provide the basis for oil spill simulation systems, systems of evaluation and control of oil spill risk and damage in seas or decision support systems. References V.I. Agoshkov. The methods of optimal control and adjoint equations in problems of mathematical physics. // Moscow: INM RAS, 2003, 256 p. (in Russian). V.I. Agoshkov, N.A. Aseev, I.S. Novikov. The methods of investigation and solution of the problems of local sources and local or integral observations. // Moscow: INM RAS, 2012. 151 p. (in Russian). N.A. Aseev, V.I. Agoshkov, V.B. Zalesny, R. Aps, P. Kujala, and J. Rytkonen. The problem of control of oil pollution risk in the Baltic Sea // Russ. J. Numer. Analysis and Math. Modelling, 2014, V 29, No. 2, 93-105. O. Liungman, J. Mattson. Scientific documentation of Seatrack Web; physical processes, algorithms and references, 2011. // https://stw-helcom.smhi.se/

Schedule Risks Due to Delays in Advanced Technology Development

NASA Technical Reports Server (NTRS)

Reeves, John D. Jr.; Kayat, Kamal A.; Lim, Evan

2008-01-01

This paper discusses a methodology and modeling capability that probabilistically evaluates the likelihood and impacts of delays in advanced technology development prior to the start of design, development, test, and evaluation (DDT&E) of complex space systems. The challenges of understanding and modeling advanced technology development considerations are first outlined, followed by a discussion of the problem in the context of lunar surface architecture analysis. The current and planned methodologies to address the problem are then presented along with sample analyses and results. The methodology discussed herein provides decision-makers a thorough understanding of the schedule impacts resulting from the inclusion of various enabling advanced technology assumptions within system design.

Methodological Problems of Soviet Pedagogy

ERIC Educational Resources Information Center

Noah, Harold J., Ed.; Beach, Beatrice S., Ed.

1974-01-01

Selected papers presented at the First Scientific Conference of Pedagogical Scholars of Socialist Countries, Moscow, 1971, deal with methodology in relation to science, human development, sociology, psychology, cybernetics, and the learning process. (KM)

[Problem based learning: achievement of educational goals in the information and comprehension sub-categories of Bloom cognitive domain].

PubMed

Montecinos, P; Rodewald, A M

1994-06-01

The aim this work was to assess and compare the achievements of medical students, subjected to problem based learning methodology. The information and comprehension categories of Bloom were tested in 17 medical students in four different occasions during the physiopathology course, using a multiple choice knowledge test. There was a significant improvement in the number of correct answers towards the end of the course. It is concluded that these medical students obtained adequate learning achievements in the information subcategory of Bloom using problem based learning methodology, during the physiopathology course.

[About History of Scientific Clinical Schools in Russia: Certain Disputable Issues of Methodology of Studying Problem].

PubMed

Borodulin, V I; Gliantsev, S P

2017-07-01

The article considers particular key methodological aspects of problem of scientific clinical school in national medicine. These aspects have to do with notion of school, its profile, issues of pedagogues, teachings and followers, subsidiary schools and issue of ethical component of scientific school. The article is a polemic one hence one will find no definite answers to specified questions. The reader is proposed to ponder over answers independently adducing examples of pro and contra. The conclusion is made about necessity of studying scientific schools in other areas of medicine and further elaboration of problem.

Collaborative Visual Analytics: A Health Analytics Approach to Injury Prevention.

PubMed

Al-Hajj, Samar; Fisher, Brian; Smith, Jennifer; Pike, Ian

2017-09-12

Background : Accurate understanding of complex health data is critical in order to deal with wicked health problems and make timely decisions. Wicked problems refer to ill-structured and dynamic problems that combine multidimensional elements, which often preclude the conventional problem solving approach. This pilot study introduces visual analytics (VA) methods to multi-stakeholder decision-making sessions about child injury prevention; Methods : Inspired by the Delphi method, we introduced a novel methodology-group analytics (GA). GA was pilot-tested to evaluate the impact of collaborative visual analytics on facilitating problem solving and supporting decision-making. We conducted two GA sessions. Collected data included stakeholders' observations, audio and video recordings, questionnaires, and follow up interviews. The GA sessions were analyzed using the Joint Activity Theory protocol analysis methods; Results : The GA methodology triggered the emergence of ' common g round ' among stakeholders. This common ground evolved throughout the sessions to enhance stakeholders' verbal and non-verbal communication, as well as coordination of joint activities and ultimately collaboration on problem solving and decision-making; Conclusion s : Understanding complex health data is necessary for informed decisions. Equally important, in this case, is the use of the group analytics methodology to achieve ' common ground' among diverse stakeholders about health data and their implications.

Photolithography diagnostic expert systems: a systematic approach to problem solving in a wafer fabrication facility

NASA Astrophysics Data System (ADS)

Weatherwax Scott, Caroline; Tsareff, Christopher R.

1990-06-01

One of the main goals of process engineering in the semiconductor industry is to improve wafer fabrication productivity and throughput. Engineers must work continuously toward this goal in addition to performing sustaining and development tasks. To accomplish these objectives, managers must make efficient use of engineering resources. One of the tools being used to improve efficiency is the diagnostic expert system. Expert systems are knowledge based computer programs designed to lead the user through the analysis and solution of a problem. Several photolithography diagnostic expert systems have been implemented at the Hughes Technology Center to provide a systematic approach to process problem solving. This systematic approach was achieved by documenting cause and effect analyses for a wide variety of processing problems. This knowledge was organized in the form of IF-THEN rules, a common structure for knowledge representation in expert system technology. These rules form the knowledge base of the expert system which is stored in the computer. The systems also include the problem solving methodology used by the expert when addressing a problem in his area of expertise. Operators now use the expert systems to solve many process problems without engineering assistance. The systems also facilitate the collection of appropriate data to assist engineering in solving unanticipated problems. Currently, several expert systems have been implemented to cover all aspects of the photolithography process. The systems, which have been in use for over a year, include wafer surface preparation (HMDS), photoresist coat and softbake, align and expose on a wafer stepper, and develop inspection. These systems are part of a plan to implement an expert system diagnostic environment throughout the wafer fabrication facility. In this paper, the systems' construction is described, including knowledge acquisition, rule construction, knowledge refinement, testing, and evaluation. The roles played by the process engineering expert and the knowledge engineer are discussed. The features of the systems are shown, particularly the interactive quality of the consultations and the ease of system use.

Innovative Mixed-Methods Research: Moving beyond Design Technicalities to Epistemological and Methodological Realizations

ERIC Educational Resources Information Center

Riazi, A. Mehdi

2016-01-01

Mixed-methods research (MMR), as an inter-discourse (quantitative and qualitative) methodology, can provide applied linguistics researchers the opportunity to draw on and integrate the strengths of the two research methodological approaches in favour of making more rigorous inferences about research problems. In this article, the argument is made…

Active Methodologies in a Queueing Systems Course for Telecommunication Engineering Studies

ERIC Educational Resources Information Center

Garcia, J.; Hernandez, A.

2010-01-01

This paper presents the results of a one-year experiment in incorporating active methodologies in a Queueing Systems course as part of the Telecommunication Engineering degree at the University of Zaragoza, Spain, during the period of adaptation to the European Higher Education Area. A problem-based learning methodology has been introduced, and…

Cognitive enhancement treatments for bipolar disorder: A systematic review and methodological recommendations.

PubMed

Miskowiak, Kamilla W; Carvalho, André F; Vieta, Eduard; Kessing, Lars V

2016-10-01

Cognitive dysfunction is an emerging treatment target in bipolar disorder (BD). Several trials have assessed the efficacy of novel pharmacological and psychological treatments on cognition in BD but the findings are contradictory and unclear. A systematic search following the PRISMA guidelines was conducted on PubMed and PsychInfo. Eligible articles reported randomized, controlled or open-label trials investigating pharmacological or psychological treatments targeting cognitive dysfunction in BD. The quality of the identified randomized controlled trials (RCTs) was evaluated with the Cochrane Collaboration's Risk of Bias tool. We identified 19 eligible studies of which 13 were RCTs and six were open-label or non-randomized studies. The findings regarding efficacy on cognition were overall disappointing or preliminary, possibly due to several methodological challenges. For the RCTs, the risk of bias was high in nine cases, unclear in one case and low in three cases. Key reasons for the high risk of bias were lack of details on the randomization process, suboptimal handling of missing data and lack of a priori priority between cognition outcomes. Other challenges were the lack of consensus on whether and how to screen for cognitive impairment and on how to assess efficacy on cognition. In conclusion, methodological problems are likely to impede the success rates of cognition trials in BD. We recommend adherence to the CONSORT guidelines for RCTs, screening for cognitive impairment before inclusion of trial participants and selection of one primary cognition outcome. Future implementation of a 'neurocircuitry-based' biomarker model to evaluate neural target engagement is warranted. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Coordinative Voltage Control Strategy with Multiple Resources for Distribution Systems of High PV Penetration: Preprint

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

Zhu, Xiangqi; Zhang, Yingchen

This paper presents an optimal voltage control methodology with coordination among different voltage-regulating resources, including controllable loads, distributed energy resources such as energy storage and photovoltaics (PV), and utility voltage-regulating devices such as voltage regulators and capacitors. The proposed methodology could effectively tackle the overvoltage and voltage regulation device distortion problems brought by high penetrations of PV to improve grid operation reliability. A voltage-load sensitivity matrix and voltage-regulator sensitivity matrix are used to deploy the resources along the feeder to achieve the control objectives. Mixed-integer nonlinear programming is used to solve the formulated optimization control problem. The methodology has beenmore » tested on the IEEE 123-feeder test system, and the results demonstrate that the proposed approach could actively tackle the voltage problem brought about by high penetrations of PV and improve the reliability of distribution system operation.« less

Topology optimization for nonlinear dynamic problems: Considerations for automotive crashworthiness

NASA Astrophysics Data System (ADS)

Kaushik, Anshul; Ramani, Anand

2014-04-01

Crashworthiness of automotive structures is most often engineered after an optimal topology has been arrived at using other design considerations. This study is an attempt to incorporate crashworthiness requirements upfront in the topology synthesis process using a mathematically consistent framework. It proposes the use of equivalent linear systems from the nonlinear dynamic simulation in conjunction with a discrete-material topology optimizer. Velocity and acceleration constraints are consistently incorporated in the optimization set-up. Issues specific to crash problems due to the explicit solution methodology employed, nature of the boundary conditions imposed on the structure, etc. are discussed and possible resolutions are proposed. A demonstration of the methodology on two-dimensional problems that address some of the structural requirements and the types of loading typical of frontal and side impact is provided in order to show that this methodology has the potential for topology synthesis incorporating crashworthiness requirements.

Artificial intelligence and design: Opportunities, research problems and directions

NASA Technical Reports Server (NTRS)

Amarel, Saul

1990-01-01

The issues of industrial productivity and economic competitiveness are of major significance in the U.S. at present. By advancing the science of design, and by creating a broad computer-based methodology for automating the design of artifacts and of industrial processes, we can attain dramatic improvements in productivity. It is our thesis that developments in computer science, especially in Artificial Intelligence (AI) and in related areas of advanced computing, provide us with a unique opportunity to push beyond the present level of computer aided automation technology and to attain substantial advances in the understanding and mechanization of design processes. To attain these goals, we need to build on top of the present state of AI, and to accelerate research and development in areas that are especially relevant to design problems of realistic complexity. We propose an approach to the special challenges in this area, which combines 'core work' in AI with the development of systems for handling significant design tasks. We discuss the general nature of design problems, the scientific issues involved in studying them with the help of AI approaches, and the methodological/technical issues that one must face in developing AI systems for handling advanced design tasks. Looking at basic work in AI from the perspective of design automation, we identify a number of research problems that need special attention. These include finding solution methods for handling multiple interacting goals, formation problems, problem decompositions, and redesign problems; choosing representations for design problems with emphasis on the concept of a design record; and developing approaches for the acquisition and structuring of domain knowledge with emphasis on finding useful approximations to domain theories. Progress in handling these research problems will have major impact both on our understanding of design processes and their automation, and also on several fundamental questions that are of intrinsic concern to AI. We present examples of current AI work on specific design tasks, and discuss new directions of research, both as extensions of current work and in the context of new design tasks where domain knowledge is either intractable or incomplete. The domains discussed include Digital Circuit Design, Mechanical Design of Rotational Transmissions, Design of Computer Architectures, Marine Design, Aircraft Design, and Design of Chemical Processes and Materials. Work in these domains is significant on technical grounds, and it is also important for economic and policy reasons.

A Qualitative Approach to a Better Understanding of the Problems Underlying Drug Shortages, as Viewed from Belgian, French and the European Union’s Perspectives

PubMed Central

Prokop, Anna; Pilc, Andrzej

2015-01-01

The problem of drug shortages has been reported worldwide, gaining prominence in multiple domains and several countries in recent years. The aim of the study was to analyze, characterise and assess this problem in Belgium and France, while also adopting a wider perspective from the European Union. A qualitative methodological approach was employed, including semi-structured interviews with the representatives of respective national health authorities, pharmaceutical companies and wholesalers, as well as hospital and community pharmacists. The research was conducted in early 2014. Four themes, which were identified through the interviews, were addressed in the paper, i.e. a) defining drug shortages, b) their dynamics and perception, c) their determinants, d) the role of the European and national institutions in coping with the problem. Three groups of determinants of drug shortages were identified throughout this study: manufacturing problems, distribution and supply problems, and problems related to economic aspects. Currently, the Member States of the European Union are striving to resolve the problem very much on their own, although a far more focused and dedicated collaboration may well prove instrumental in coping with drug shortages throughout Europe more effectively. To the best of the authors’ knowledge, this is the first qualitative study to investigate the characteristics, key determinants, and the problem drivers of drug shortages, focusing on this particular group of countries, while also adopting the European Union’s perspective. PMID:25942432

Health effects of exposure to waste incinerator emissions:a review of epidemiological studies.

PubMed

Franchini, Michela; Rial, Michela; Buiatti, Eva; Bianchi, Fabrizio

2004-01-01

This review evaluates the epidemiological literature on health effects in relation to incineration facilities. Several adverse health effects have been reported. Significant exposure-disease associations are reported by two thirds of the papers focusing on cancer (lung and larynx cancer, non-Hodgkin's lymphoma). Positive associations were found for congenital malformations and residence near incinerators. Exposure to PCB and heavy metals were associated with several health outcomes and in particular with reduction of thyroid hormones. Findings on non-carcinogen pathologies are inconclusive. Effect of biases and confounding factors must be considered in the explanation of findings. Methodological problems and insufficient exposure information generate difficulties on study results. Research needs include a better definition of exposure in qualitative and quantitative terms in particular by developing the use of biomarkers and by implementing environmental measurements.

Comment on "Most computational hydrology is not reproducible, so is it really science?" by Christopher Hutton et al.

NASA Astrophysics Data System (ADS)

Añel, Juan A.

2017-03-01

Nowadays, the majority of the scientific community is not aware of the risks and problems associated with an inadequate use of computer systems for research, mostly for reproducibility of scientific results. Such reproducibility can be compromised by the lack of clear standards and insufficient methodological description of the computational details involved in an experiment. In addition, the inappropriate application or ignorance of copyright laws can have undesirable effects on access to aspects of great importance of the design of experiments and therefore to the interpretation of results.