Reflectivity of crack sealant.
DOT National Transportation Integrated Search
2002-01-01
Crack sealing is used in road maintenance but presents a problem when crack seal material visually pops out on the roadway, making it difficult to see lane stripes. This problem will increase as New Mexico increases its use of crack sealants. This su...
The mGA1.0: A common LISP implementation of a messy genetic algorithm
NASA Technical Reports Server (NTRS)
Goldberg, David E.; Kerzic, Travis
1990-01-01
Genetic algorithms (GAs) are finding increased application in difficult search, optimization, and machine learning problems in science and engineering. Increasing demands are being placed on algorithm performance, and the remaining challenges of genetic algorithm theory and practice are becoming increasingly unavoidable. Perhaps the most difficult of these challenges is the so-called linkage problem. Messy GAs were created to overcome the linkage problem of simple genetic algorithms by combining variable-length strings, gene expression, messy operators, and a nonhomogeneous phasing of evolutionary processing. Results on a number of difficult deceptive test functions are encouraging with the mGA always finding global optima in a polynomial number of function evaluations. Theoretical and empirical studies are continuing, and a first version of a messy GA is ready for testing by others. A Common LISP implementation called mGA1.0 is documented and related to the basic principles and operators developed by Goldberg et. al. (1989, 1990). Although the code was prepared with care, it is not a general-purpose code, only a research version. Important data structures and global variations are described. Thereafter brief function descriptions are given, and sample input data are presented together with sample program output. A source listing with comments is also included.
ERIC Educational Resources Information Center
Lehmann, M.; Christensen, P.; Du, X.; Thrane, M.
2008-01-01
In a world where systems are increasingly larger, where their boundaries are often difficult to identify, and where societal rather than technical issues play increasingly bigger roles, problems cannot be solved by applying a technical solution alone. It thus becomes important for engineers to be skilled not only in terms of their particular…
The Crisis Manual for Early Childhood Teachers: How To Handle the Really Difficult Problems.
ERIC Educational Resources Information Center
Miller, Karen
More and more teachers report the increasing incidence of crises in children's lives, crises that interfere with the child's ability to learn. Noting that developmentally appropriate curricula must respond to the issues of immediate concern and interest to children, this source book assists teachers in facing difficult issues in the classroom and…
Distraction during learning with hypermedia: difficult tasks help to keep task goals on track
Scheiter, Katharina; Gerjets, Peter; Heise, Elke
2014-01-01
In educational hypermedia environments, students are often confronted with potential sources of distraction arising from additional information that, albeit interesting, is unrelated to their current task goal. The paper investigates the conditions under which distraction occurs and hampers performance. Based on theories of volitional action control it was hypothesized that interesting information, especially if related to a pending goal, would interfere with task performance only when working on easy, but not on difficult tasks. In Experiment 1, 66 students learned about probability theory using worked examples and solved corresponding test problems, whose task difficulty was manipulated. As a second factor, the presence of interesting information unrelated to the primary task was varied. Results showed that students solved more easy than difficult probability problems correctly. However, the presence of interesting, but task-irrelevant information did not interfere with performance. In Experiment 2, 68 students again engaged in example-based learning and problem solving in the presence of task-irrelevant information. Problem-solving difficulty was varied as a first factor. Additionally, the presence of a pending goal related to the task-irrelevant information was manipulated. As expected, problem-solving performance declined when a pending goal was present during working on easy problems, whereas no interference was observed for difficult problems. Moreover, the presence of a pending goal reduced the time on task-relevant information and increased the time on task-irrelevant information while working on easy tasks. However, as revealed by mediation analyses these changes in overt information processing behavior did not explain the decline in problem-solving performance. As an alternative explanation it is suggested that goal conflicts resulting from pending goals claim cognitive resources, which are then no longer available for learning and problem solving. PMID:24723907
NMESys: An expert system for network fault detection
NASA Technical Reports Server (NTRS)
Nelson, Peter C.; Warpinski, Janet
1991-01-01
The problem of network management is becoming an increasingly difficult and challenging task. It is very common today to find heterogeneous networks consisting of many different types of computers, operating systems, and protocols. The complexity of implementing a network with this many components is difficult enough, while the maintenance of such a network is an even larger problem. A prototype network management expert system, NMESys, implemented in the C Language Integrated Production System (CLIPS). NMESys concentrates on solving some of the critical problems encountered in managing a large network. The major goal of NMESys is to provide a network operator with an expert system tool to quickly and accurately detect hard failures, potential failures, and to minimize or eliminate user down time in a large network.
LaGasse, Linda L.; Conradt, Elisabeth; Karalunas, Sarah L.; Dansereau, Lynne M.; Butner, Jonathan E.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles R.; Whitaker, Toni M.; Lester, Barry M.
2016-01-01
Developmental psychopathologists face the difficult task of identifying the environmental conditions that may contribute to early childhood behavior problems. Highly stressed caregivers can exacerbate behavior problems, while children with behavior problems may make parenting more difficult and increase caregiver stress. Unknown is: (1) how these transactions originate, (2) whether they persist over time to contribute to the development of problem behavior and (3) what role resilience factors, such as child executive functioning, may play in mitigating the development of problem behavior. In the present study, transactional relations between caregiving stress, executive functioning, and behavior problems were examined in a sample of 1,388 children with prenatal drug exposures at three developmental time points: early childhood (birth-age 5), middle childhood (ages 6 to 9), and early adolescence (ages 10 to 13). Transactional relations differed between caregiving stress and internalizing versus externalizing behavior. Targeting executive functioning in evidence-based interventions for children with prenatal substance exposure who present with internalizing problems and treating caregiving psychopathology, depression, and parenting stress in early childhood may be particularly important for children presenting with internalizing behavior. PMID:27427803
Integrated Maintenance Information System (IMIS): A Maintenance Information Delivery Concept.
1987-11-01
InterFace Figure 2. Portable Maintenance Computer Concept. provide advice for difficult fault-isolation problems . The technician will be able to accomplish...faced with an ever-growing number of paper-based technical orders (TOs). This has greatly increased costs and distribution problems . In addition, it has...compounded problems associ- ated with ensuring accurate data and the lengthy correction times involved. To improve the accuracy of technical data and
Modeling of bleach plant washer mineral scale
Alan Rudie; Peter Hart
2004-01-01
One of the more common areas of mineral scale formation in bleach plants is on washer face wires and the extraction rings of diffusion washers. Whereas most scale problems can be understood as a mixing of two streams that increase the concentrations of anions and cations and exceed a solubility product, washer problems are often more difficult to understand. The...
School-Based Mental Health Services for Adolescents: School Psychology in Contemporary Society
ERIC Educational Resources Information Center
Crespi, Tony D.; Hughes, Tammy L.
2004-01-01
Adolescents are in crisis in school, home, and in the community. With an increasing array of problems, from alcohol and drug addiction to teenage pregnancy, the nation's youth are facing difficult challenges. In particular, family problems experienced by adolescents alone can seem daunting, with such issues as divorce, abuse, and discord changing…
Increasing Interest in Cognitive Psychology Using Scenario-Based Assessment
ERIC Educational Resources Information Center
Cormack, Sophie
2014-01-01
Students often perceive cognitive psychology as an abstract and difficult subject with little intrinsic interest. When student feedback identified problems with the traditional essay assessment in a cognitive psychology module, action research led to the development of a forensic scenario-based assessment which successfully increased student…
Improving Virtual Teams through Knowledge Management: A Case Study
ERIC Educational Resources Information Center
Laughridge, James F.
2012-01-01
Within the dynamic globalized operating environment, organizations are increasingly relying on virtual teams to solve their most difficult problems, leverage their expertise and expand their presence. The use of virtual teams by organizations continues to increase greatly as the technologies supporting them evolve. Despite improvements in…
Psychology: Climate change hits home
NASA Astrophysics Data System (ADS)
Weber, Elke U.
2011-04-01
Engaging the public with climate change has proved difficult, in part because they see the problem as remote. New evidence suggests that direct experience of one anticipated impact -- flooding -- increases people's concern and willingness to save energy.
R-U-Typing-2-Me? Evolving a Chat Tool to Increase Understanding in Learning Activities
ERIC Educational Resources Information Center
Fuks, Hugo; Pimentel, Mariano; Lucena, Carlos Jose Pereira de
2006-01-01
Very often, when using a chat tool where more than one participant is talking simultaneously, it is difficult to follow the conversation, read all the different messages and work out who is talking to whom about what. This problem has been dubbed "Chat Confusion." This article investigates this problem in debate sessions in an online university…
Printed circuit boards: a review on the perspective of sustainability.
Canal Marques, André; Cabrera, José-María; Malfatti, Célia de Fraga
2013-12-15
Modern life increasingly requires newer equipments and more technology. In addition, the fact that society is highly consumerist makes the amount of discarded equipment as well as the amount of waste from the manufacture of new products increase at an alarming rate. Printed circuit boards, which form the basis of the electronics industry, are technological waste of difficult disposal whose recycling is complex and expensive due to the diversity of materials and components and their difficult separation. Currently, printed circuit boards have a fixing problem, which is migrating from traditional Pb-Sn alloys to lead-free alloys without definite choice. This replacement is an attempt to minimize the problem of Pb toxicity, but it does not change the problem of separation of the components for later reuse and/or recycling and leads to other problems, such as temperature rise, delamination, flaws, risks of mechanical shocks and the formation of "whiskers". This article presents a literature review on printed circuit boards, showing their structure and materials, the environmental problem related to the board, some the different alternatives for recycling, and some solutions that are being studied to reduce and/or replace the solder, in order to minimize the impact of solder on the printed circuit boards. Copyright © 2013 Elsevier Ltd. All rights reserved.
Tuberculous otitis media: two case reports and literature review.
Awan, Mohammad Sohail; Salahuddin, Iftikhar
2002-11-01
Tuberculous otitis media can be difficult to diagnose because it can easily be confused with other acute or chronic middle ear conditions. Compounding this problem is the fact that physicians are generally unfamiliar with the typical features of tuberculous otitis media. Finally, the final diagnosis can be difficult because it requires special culture and pathologic studies. To increase awareness of this condition, we describe two cases of tuberculous otitis media and we review the literature.
Behavior of Epoxy-Coated Textured Reinforcing Bars
DOT National Transportation Integrated Search
2018-04-01
Cracking in bridge decks is a common but difficult problem to control. Both research and experience show that the use of epoxy-coated reinforcement, which is mandated by most state departments of transportation (DOTs) for bridge decks, increases c...
Tips for safety in endoscopic submucosal dissection for colorectal tumors
Naito, Yuji; Murakami, Takaaki; Hirose, Ryohei; Ogiso, Kiyoshi; Inada, Yutaka; Abdul Rani, Rafiz; Kishimoto, Mitsuo; Nakanishi, Masayoshi; Itoh, Yoshito
2017-01-01
In Japan, endoscopic submucosal dissection (ESD) becomes one of standard therapies for large colorectal tumors. Recently, the efficacy of ESD has been reported all over the world. However, it is still difficult even for Japanese experts in some situations. Right-sided location, large tumor size, high degree of fibrosis, difficult manipulation is related with the difficulty. However, improvements on ESD devices, suitable strategies, and increase of operators’ experiences enable us to solve these problems. In this chapter, we introduce recent topics about various difficult factors of colorectal ESD and the tips such as strategy, devices, injection, and traction method [Pocket-creation method (PCM) etc.]. PMID:28616400
The analysis method of the DRAM cell pattern hotspot
NASA Astrophysics Data System (ADS)
Lee, Kyusun; Lee, Kweonjae; Chang, Jinman; Kim, Taeheon; Han, Daehan; Hong, Aeran; Kim, Yonghyeon; Kang, Jinyoung; Choi, Bumjin; Lee, Joosung; Lee, Jooyoung; Hong, Hyeongsun; Lee, Kyupil; Jin, Gyoyoung
2015-03-01
It is increasingly difficult to determine degree of completion of the patterning and the distribution at the DRAM Cell Patterns. When we research DRAM Device Cell Pattern, there are three big problems currently, it is as follows. First, due to etch loading, it is difficult to predict the potential defect. Second, due to under layer topology, it is impossible to demonstrate the influence of the hotspot. Finally, it is extremely difficult to predict final ACI pattern by the photo simulation, because current patterning process is double patterning technology which means photo pattern is completely different from final etch pattern. Therefore, if the hotspot occurs in wafer, it is very difficult to find it. CD-SEM is the most common pattern measurement tool in semiconductor fabrication site. CD-SEM is used to accurately measure small region of wafer pattern primarily. Therefore, there is no possibility of finding places where unpredictable defect occurs. Even though, "Current Defect detector" can measure a wide area, every chip has same pattern issue, the detector cannot detect critical hotspots. Because defect detecting algorithm of bright field machine is based on image processing, if same problems occur on compared and comparing chip, the machine cannot identify it. Moreover this instrument is not distinguished the difference of distribution about 1nm~3nm. So, "Defect detector" is difficult to handle the data for potential weak point far lower than target CD. In order to solve those problems, another method is needed. In this paper, we introduce the analysis method of the DRAM Cell Pattern Hotspot.
Mack, Jennifer W; Ilowite, Maya; Taddei, Sarah
2017-02-15
Previous work on difficult relationships between patients and physicians has largely focused on the adult primary care setting and has typically held patients responsible for challenges. Little is known about experiences in pediatrics and more serious illness; therefore, we examined difficult relationships between parents and physicians of children with cancer. This was a cross-sectional, semistructured interview study of parents and physicians of children with cancer at the Dana-Farber Cancer Institute and Boston Children's Hospital (Boston, Mass) in longitudinal primary oncology relationships in which the parent, physician, or both considered the relationship difficult. Interviews were audiotaped, transcribed, and subjected to a content analysis. Dyadic parent and physician interviews were performed for 29 relationships. Twenty were experienced as difficult by both parents and physicians; 1 was experienced as difficult by the parent only; and 8 were experienced as difficult by the physician only. Parent experiences of difficult relationships were characterized by an impaired therapeutic alliance with physicians; physicians experienced difficult relationships as demanding. Core underlying issues included problems of connection and understanding (n = 8), confrontational parental advocacy (n = 16), mental health issues (n = 2), and structural challenges to care (n = 3). Although problems of connection and understanding often improved over time, problems of confrontational advocacy tended to solidify. Parents and physicians both experienced difficult relationships as highly distressing. Although prior conceptions of difficult relationships have held patients responsible for challenges, this study has found that difficult relationships follow several patterns. Some challenges, such as problems of connection and understanding, offer an opportunity for healing. However, confrontational advocacy appears especially refractory to repair; special consideration of these relationships and avenues for repairing them are needed. Cancer 2017;123:675-681. © 2016 American Cancer Society. © 2016 American Cancer Society.
State-of-the-art research on electromagnetic information security
NASA Astrophysics Data System (ADS)
Hayashi, Yu-ichi
2016-07-01
As information security is becoming increasingly significant, security at the hardware level is as important as in networks and applications. In recent years, instrumentation has become cheaper and more precise, computation has become faster, and capacities have increased. With these advancements, the threat of advanced attacks that were considerably difficult to carry out previously has increased not only in military and diplomatic fields but also in general-purpose manufactured devices. This paper focuses on the problem of the security limitations concerning electromagnetic waves (electromagnetic information security) that has rendered attack detection particularly difficult at the hardware level. In addition to reviewing the mechanisms of these information leaks and countermeasures, this paper also presents the latest research trends and standards.
Why Is the Overheating Problem Difficult: the Role of Entropy
NASA Technical Reports Server (NTRS)
Liou, Meng-Sing
2013-01-01
The development of computational fluid dynamics over the last few decades has yielded enormous successes and capabilities being routinely employed today; however there remain some open problems to be properly resolved-some are fundamental in nature and some resolvable by operational changes. These two categories are distinguished and broadly explored previously. One, that belongs to the former, is the so-called overheating problem, especially in rarefying flow. This problem up to date still dogs every method known to the author; a solution to it remains elusive. The study in this paper concludes that: (1) the entropy increase is quantitatively linked to the increase in the temperature increase, (2) it is argued that the overheating is inevitable in the current shock capturing or traditional finite difference framework, and (3) a simple hybrid method is proposed that removes the overheating problem in the rarefying problems, but also retains the property of accurate shock capturing. This remedy (enhancement of current numerical methods) can be included easily in the present Eulerian codes.
Insight into the ten-penny problem: guiding search by constraints and maximization.
Öllinger, Michael; Fedor, Anna; Brodt, Svenja; Szathmáry, Eörs
2017-09-01
For a long time, insight problem solving has been either understood as nothing special or as a particular class of problem solving. The first view implicates the necessity to find efficient heuristics that restrict the search space, the second, the necessity to overcome self-imposed constraints. Recently, promising hybrid cognitive models attempt to merge both approaches. In this vein, we were interested in the interplay of constraints and heuristic search, when problem solvers were asked to solve a difficult multi-step problem, the ten-penny problem. In three experimental groups and one control group (N = 4 × 30) we aimed at revealing, what constraints drive problem difficulty in this problem, and how relaxing constraints, and providing an efficient search criterion facilitates the solution. We also investigated how the search behavior of successful problem solvers and non-solvers differ. We found that relaxing constraints was necessary but not sufficient to solve the problem. Without efficient heuristics that facilitate the restriction of the search space, and testing the progress of the problem solving process, the relaxation of constraints was not effective. Relaxing constraints and applying the search criterion are both necessary to effectively increase solution rates. We also found that successful solvers showed promising moves earlier and had a higher maximization and variation rate across solution attempts. We propose that this finding sheds light on how different strategies contribute to solving difficult problems. Finally, we speculate about the implications of our findings for insight problem solving.
The Difficult Patron in the Academic Library: Problem Issues or Problem Patrons?
ERIC Educational Resources Information Center
Simmonds Patience L.; Ingold, Jane L.
2002-01-01
Identifies difficult patron issues in academic libraries from the librarians' perspectives and offers solutions to try and prevent them from becoming problems. Topics include labeling academic library users; eliminating sources of conflict between faculty and library staff; and conflicts between students and library staff. (Author/LRW)
Groin injuries in sport: treatment strategies.
Lynch, S A; Renström, P A
1999-08-01
Groin pain in athletes is a common problem that can result in significant amounts of missed playing time. Many of the problems are related to the musculoskeletal system, but care must be taken not to overlook other more serious and potentially life threatening medical cases of pelvis and groin pain. Stress fractures of the bones of the pelvis occur, particularly after a sudden increase in the intensity of training. Most of these stress fractures will heal with rest, but femoral neck stress fractures can potentially lead to more serious problems, and require closer evaluation and sometimes surgical treatment. Avulsion fractures of the apophyses occur through the relatively weaker growth plate in adolescents. Most of these will heal with a graduated physical therapy programme and do not need surgery. Osteitis pubis is characterised by sclerosis and bony changes about the pubic symphysis. This is a self-limiting disease that can take several months to resolve. Corticosteroid injection can sometimes hasten the rehabilitation process. Sports hernias can cause prolonged groin pain, and provide a difficult diagnostic dilemma. In athletes with prolonged groin pain, with increased pain during valsalva manoeuvres and tenderness along the posterior inguinal wall and external canal, an insidious sports hernia should be considered. In cases of true sports hernia, treatment is by surgical reinforcement of the inguinal wall. Nerve compression can occur to the nerves supplying the groin. In cases that do not respond to desensitisation measures, neurolysis can relieve the pain. Adductor strains are common problems in kicking sports such as soccer. The majority of these are incomplete muscle tendon tears that occur just adjacent to, the musculotendinous junction. Most of these will respond to a graduated stretching and strengthening programme, but these can sometimes take a long time to completely heal. Patience is the key to obtain complete healing, because a return to sports too early can lead to chronic pain, which becomes increasingly difficult to treat. Management of groin injuries can be challenging, and diagnosis can be difficult because of the degree of overlap of symptoms between the different problems. By careful history and clinical examination, with judicious use of special tests and good team work, a correct diagnosis can be obtained.
Computer-aided programming for message-passing system; Problems and a solution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, M.Y.; Gajski, D.D.
1989-12-01
As the number of processors and the complexity of problems to be solved increase, programming multiprocessing systems becomes more difficult and error-prone. Program development tools are necessary since programmers are not able to develop complex parallel programs efficiently. Parallel models of computation, parallelization problems, and tools for computer-aided programming (CAP) are discussed. As an example, a CAP tool that performs scheduling and inserts communication primitives automatically is described. It also generates the performance estimates and other program quality measures to help programmers in improving their algorithms and programs.
Misleading Gastrointestinal Symptoms: The Ongoing Story of Chronic Lead Intoxication.
Macedo, Guilherme; Lopes, Susana; Peixoto, Armando
2016-10-01
Inorganic lead intoxication has emerged as an important and challenging clinical problem owing to increased awareness of lead and enhanced surveillance of exposed individuals. However, recognition may not be very difficult when there is an obvious history of exposure. Our interest began a few years ago when we could trace an outbreak, following a patient who was admitted with colickly abdominal pain, convulsions, and coma. After that, 16 more cases were identified and characterized. All patients recovered completely after adequate chelation therapy. Although the clinical picture of lead intoxication is pleomorphic, the increased awareness of gastroenterologists in this subject may possibly bring chronically complaining difficult patients to an earlier, unexpected, and fairly treatable disease.
MAA Placement Test Newsletter. 1978-87.
ERIC Educational Resources Information Center
Harvey, John G., Ed.
1987-01-01
This document consists of volumes 1-9 of the Mathematics Association of America's (MAA) Placement Test Program Newsletter. The MAA is the professional association primarily concerned with undergraduate education in mathematics. It has responded to the increasingly difficult problem of placing freshmen students in mathematics courses by developing…
ROLE OF OCEANIC AND RIVERINE SOURCES IN NUTRIENT AND PHYTOPLANKTON DYNAMICS IN YAQUINA BAY, OREGON
There is evidence that coastal ecosystems are experiencing environmental problems due to excess nutrients. The numerous sources, forms, and pathways of nutrients make it difficult to determine the effect of increases in anthropogenic loading. This is particularly evident in Pac...
Why Do Disadvantaged Filipino Children Find Word Problems in English Difficult?
ERIC Educational Resources Information Center
Bautista, Debbie; Mulligan, Joanne
2010-01-01
Young Filipino students are expected to solve mathematical word problems in English, a language that many encounter only in schools. Using individual interviews of 17 Filipino children, we investigated why word problems in English are difficult and the extent to which the language interferes with performance. Results indicate that children could…
Responding to Bullying: What Works?
ERIC Educational Resources Information Center
Craig, Wendy; Pepler, Debra; Blais, Julie
2007-01-01
Children who are bullied are often told to "solve the problems themselves"; however, when bullying is repeated over time, it becomes increasingly difficult for victimized children to stop the torment because of their relative lack of power. We examine the ways in which children respond to bullying and their evaluations of the…
Creative Strategies in Difficult Times
ERIC Educational Resources Information Center
Lucas, Susann
2003-01-01
It is a frequent, if not ongoing, problem: deep funding cuts despite increased enrollments, and accompanying need for more instructors and updated technology. According to Joe Barwick, Roy Flores, Bernadine Chuck Fong, Al Lorenzo, Judith Redwine, and Jerry Sue Thornton, community colleges should start at the top when they deal with institutional…
Every Kid a Winner: Accountability in Education.
ERIC Educational Resources Information Center
Lessinger, Leon M.
One of the originators of performance contracting explains how school districts can use that concept to attack difficult educational problems and meet the increasing demand that schools be held accountable for their educational product. The author argues that what he calls "educational engineering" will guarantee a basic level of achievement in…
Kochanska, Grazyna; Kim, Sanghag
2012-01-01
Background Research has shown that interactions between young children’s temperament and the quality of care they receive predict the emergence of positive and negative socioemotional developmental outcomes. This multi-method study addresses such interactions, using observed and mother-rated measures of difficult temperament, children’s committed, self-regulated compliance and externalizing problems, and mothers’ responsiveness in a low-income sample. Methods In 186 30-month-old children, difficult temperament was observed in the laboratory (as poor effortful control and high anger proneness), and rated by mothers. Mothers’ responsiveness was observed in lengthy naturalistic interactions at 30 and 33 months. At 40 months, children’s committed compliance and externalizing behavior problems were assessed using observations and several well-established maternal report instruments. Results Parallel significant interactions between child difficult temperament and maternal responsiveness were found across both observed and mother-rated measures of temperament. For difficult children, responsiveness had a significant effect such that those children were more compliant and had fewer externalizing problems when they received responsive care, but were less compliant and had more behavior problems when they received unresponsive care. For children with easy temperaments, maternal responsiveness and developmental outcomes were unrelated. All significant interactions reflected the diathesis-stress model. There was no evidence of differential susceptibility, perhaps due to the pervasive stress present in the ecology of the studied families. Conclusions Those findings add to the growing body of evidence that for temperamentally difficult children, unresponsive parenting exacerbates risks for behavior problems, but responsive parenting can effectively buffer risks conferred by temperament. PMID:23057713
A Research Methodology for Studying What Makes Some Problems Difficult to Solve
ERIC Educational Resources Information Center
Gulacar, Ozcan; Fynewever, Herb
2010-01-01
We present a quantitative model for predicting the level of difficulty subjects will experience with specific problems. The model explicitly accounts for the number of subproblems a problem can be broken into and the difficultly of each subproblem. Although the model builds on previously published models, it is uniquely suited for blending with…
Problem-based learning biotechnology courses in chemical engineering.
Glatz, Charles E; Gonzalez, Ramon; Huba, Mary E; Mallapragada, Surya K; Narasimhan, Balaji; Reilly, Peter J; Saunders, Kevin P; Shanks, Jacqueline V
2006-01-01
We have developed a series of upper undergraduate/graduate lecture and laboratory courses on biotechnological topics to supplement existing biochemical engineering, bioseparations, and biomedical engineering lecture courses. The laboratory courses are based on problem-based learning techniques, featuring two- and three-person teams, journaling, and performance rubrics for guidance and assessment. Participants initially have found them to be difficult, since they had little experience with problem-based learning. To increase enrollment, we are combining the laboratory courses into 2-credit groupings and allowing students to substitute one of them for the second of our 2-credit chemical engineering unit operations laboratory courses.
ERIC Educational Resources Information Center
Taber, Mary R.
2013-01-01
Mathematics can be a difficult topic both to teach and to learn. Word problems specifically can be difficult for students with disabilities because they have to conceptualize what the problem is asking for, and they must perform the correct operation accurately. Current trends in mathematics instruction stem from the National Council of Teachers…
Sensitivity and bias under conditions of equal and unequal academic task difficulty.
Reed, Derek D; Martens, Brian K
2008-01-01
We conducted an experimental analysis of children's relative problem-completion rates across two workstations under conditions of equal (Experiment 1) and unequal (Experiment 2) problem difficulty. Results were described using the generalized matching equation and were evaluated for degree of schedule versus stimulus control. Experiment 1 involved a symmetrical choice arrangement in which the children could earn points exchangeable for rewards contingent on correct math problem completion. Points were delivered according to signaled variable-interval schedules at each workstation. For 2 children, relative rates of problem completion appeared to have been controlled by the schedule requirements in effect and matched relative rates of reinforcement, with sensitivity values near 1 and bias values near 0. Experiment 2 involved increasing the difficulty of math problems at one of the workstations. Sensitivity values for all 3 participants were near 1, but a substantial increase in bias toward the easier math problems was observed. This bias was possibly associated with responding at the more difficult workstation coming under stimulus control rather than schedule control.
Plant invasions in mountains: global lessons for better management
Keith L. McDougall; Anzar A. Khuroo; Lloyd L. Loope; Catherine G. Parks; Anibal Pauchard; Zafar A. Reshi; Ian Rushworth; Christoph Kueffer
2011-01-01
Mountains are one of few ecosystems little affected by plant invasions. However, the threat of invasion is likely to increase because of climate change, greater anthropogenic land use, and continuing novel introductions. Preventive management, therefore, will be crucial but can be difficult to promote when more pressing problems are unresolved and predictions are...
Measuring Financial Capability and Its Determinants Using Survey Data
ERIC Educational Resources Information Center
Taylor, Mark
2011-01-01
Financial capability, or people's ability to manage and take control of their finances, is receiving increasing interest among policy makers as more people find themselves in difficult financial situations during the current economic downturn. We tackle the problem of how to measure financial capability--with a specific focus on making ends meet…
Pronunciation Problems of Chinese Learners of English
ERIC Educational Resources Information Center
Han, Feifei
2013-01-01
Increasingly, Chinese students are pursuing their studies abroad in English-speaking countries, such as the USA, the UK, Australia, and New Zealand. Despite the fact that they have studied English as a compulsory subject for a number of years and have passed multiple English proficiency tests, many still find it is difficult to communicate well in…
Information and knowledge management in support of sustainable forestry: a review
H. Michael Rauscher; Daniel L. Schmoldt; Harald Vacik
2007-01-01
For individuals, organizations and nations, success and even survival depend upon making good decisions. Doing so can be extremely difficult when problems are not well structured and situations are complex, as they are for natural resource management. Recent advances in computer technology coupled with the increase in accessibility brought about by the...
Vegetation mapping as a guide to better silviculture
Marinus. Westveld
1951-01-01
Difficult and challenging problems confront the forester today. Disastrous floods, critical water shortages, and the uninterrupted trend of forest depletion have focused attention on the important role forests play in the strength, economy, and prosperity of the Nation. Forests are increasingly prized for recreation, the protection they afford sources of water, and...
ERIC Educational Resources Information Center
Gubasta, Joseph L.
The numerous issues and problems facing college and university decisionmakers and the ever increasing information needs of external agency representatives place conflicting pressures on institutional research personnel, forcing them to make difficult decisions regarding the allocation of their resources. Outlined are several such pressures. It is…
An Ethical Exercise for the Social Studies Classroom: The Trolley Dilemma
ERIC Educational Resources Information Center
Lennon, Sean M.; Byford, Jeffrey M.; Cox, J. T.
2015-01-01
The Trolley Problem as defined in this paper is a series, or continuation, of increasingly difficult ethical riddles successfully implemented in a classroom environment to spur complex, critical thinking and dialogue. The activity is designed upon the scenario of a runaway train with different and challenging choices, segueing neatly into group…
ERIC Educational Resources Information Center
He, Yi; Swenson, Sandra; Lents, Nathan
2012-01-01
Educational technology has enhanced, even revolutionized, pedagogy in many areas of higher education. This study examines the incorporation of video tutorials as a supplement to learning in an undergraduate analytical chemistry course. The concepts and problems in which students faced difficulty were first identified by assessing students'…
Locating difficult veins for venepuncture and cannulation.
Shaw, Sally Jane
2017-02-15
Vein location and assessment are essential to improve the success rates for vascular access. However, problems remain with first attempt success rates for peripheral cannulation and locating difficult veins. Practitioners may not be aware of developments in technology and aids to assist in the location and assessment of veins to achieve vascular access. This article provides an overview of two vein location aids that can be used to locate difficult veins: the IV-eye vein imager and the Vacuderm tourniquet. It discusses the patient factors that can increase the difficulty of vein assessment and location, and emphasises the importance of vessel health and preservation, and vein palpation. Practitioners should be experienced and skilled in the assessment of veins, and they are encouraged to revisit how they locate and assess veins.
Drinkers and bettors: investigating the complementarity of alcohol consumption and problem gambling.
French, Michael T; Maclean, Johanna Catherine; Ettner, Susan L
2008-07-01
Regulated gambling is a multi-billion dollar industry in the United States with greater than 100% increases in revenue over the past decade. Along with this rise in gambling popularity and gaming options comes an increased risk of addiction and the associated social costs. This paper focuses on the effect of alcohol use on gambling-related problems. Variables correlated with both alcohol use and gambling may be difficult to observe, and the inability to include these items in empirical models may bias coefficient estimates. After addressing the endogeneity of alcohol use when appropriate, we find strong evidence that problematic gambling and alcohol consumption are complementary activities.
Adaptivity and smart algorithms for fluid-structure interaction
NASA Technical Reports Server (NTRS)
Oden, J. Tinsley
1990-01-01
This paper reviews new approaches in CFD which have the potential for significantly increasing current capabilities of modeling complex flow phenomena and of treating difficult problems in fluid-structure interaction. These approaches are based on the notions of adaptive methods and smart algorithms, which use instantaneous measures of the quality and other features of the numerical flowfields as a basis for making changes in the structure of the computational grid and of algorithms designed to function on the grid. The application of these new techniques to several problem classes are addressed, including problems with moving boundaries, fluid-structure interaction in high-speed turbine flows, flow in domains with receding boundaries, and related problems.
Psychosocial aspects of head and neck cancer--a review of the literature.
Pruyn, J F; de Jong, P C; Bosman, L J; van Poppel, J W; van Den Borne, H W; Ryckman, R M; de Meij, K
1986-12-01
This study is a systematic analysis of the literature on psychosocial aspects in head and neck cancer patients. Patients with head and neck cancer experience a variety of physical as well as psychosocial problems. Physical problems include swallowing or chewing, speech and physical appearance. Psychosocial problems include anxiety, depression, loss of self-esteem and uncertainty about the future. Because of these problems, isolation from friends typically occurs, re-employment is difficult, and there are social and sexual tensions within families. Information and support by professionals, partners and/or fellow patients are related to positive rehabilitation outcomes such as the acquisition of speech, increases in constructive social functioning and decreases in depression.
Social cognition and social problem solving abilities in individuals with alcohol use disorder.
Schmidt, Tobias; Roser, Patrik; Juckel, Georg; Brüne, Martin; Suchan, Boris; Thoma, Patrizia
2016-11-01
Up to now, little is known about higher order cognitive abilities like social cognition and social problem solving abilities in alcohol-dependent patients. However, impairments in these domains lead to an increased probability for relapse and are thus highly relevant in treatment contexts. This cross-sectional study assessed distinct aspects of social cognition and social problem solving in 31 hospitalized patients with alcohol use disorder (AUD) and 30 matched healthy controls (HC). Three ecologically valid scenario-based tests were used to gauge the ability to infer the mental state of story characters in complicated interpersonal situations, the capacity to select the best problem solving strategy among other less optimal alternatives, and the ability to freely generate appropriate strategies to handle difficult interpersonal conflicts. Standardized tests were used to assess executive function, attention, trait empathy, and memory, and correlations were computed between measures of executive function, attention, trait empathy, and tests of social problem solving. AUD patients generated significantly fewer socially sensitive and practically effective solutions for problematic interpersonal situations than the HC group. Furthermore, patients performed significantly worse when asked to select the best alternative among a list of presented alternatives for scenarios containing sarcastic remarks and had significantly more problems to interpret sarcastic remarks in difficult interpersonal situations. These specific patterns of impairments should be considered in treatment programs addressing impaired social skills in individuals with AUD.
Difficult incidents and tutor interventions in problem-based learning tutorials.
Kindler, Pawel; Grant, Christopher; Kulla, Steven; Poole, Gary; Godolphin, William
2009-09-01
Tutors report difficult incidents and distressing conflicts that adversely affect learning in their problem-based learning (PBL) groups. Faculty development (training) and peer support should help them to manage this. Yet our understanding of these problems and how to deal with them often seems inadequate to help tutors. The aim of this study was to categorise difficult incidents and the interventions that skilled tutors used in response, and to determine the effectiveness of those responses. Thirty experienced and highly rated tutors in our Year 1 and 2 medical curriculum took part in semi-structured interviews to: identify and describe difficult incidents; describe how they responded, and assess the success of each response. Recorded and transcribed data were analysed thematically to develop typologies of difficult incidents and interventions and compare reported success or failure. The 94 reported difficult incidents belonged to the broad categories 'individual student' or 'group dynamics'. Tutors described 142 interventions in response to these difficult incidents, categorised as: (i) tutor intervenes during tutorial; (ii) tutor gives feedback outside tutorial, or (iii) student or group intervenes. Incidents in the 'individual student' category were addressed relatively unsuccessfully (effective < 50% of the time) by response (i), but with moderate success by response (ii) and successfully (> 75% of the time) by response (iii). None of the interventions worked well when used in response to problems related to 'group dynamics'. Overall, 59% of the difficult incidents were dealt with successfully. Dysfunctional PBL groups can be highly challenging, even for experienced and skilled tutors. Within-tutorial feedback, the treatment that tutors are most frequently advised to apply, was often not effective. Our study suggests that the collective responsibility of the group, rather than of the tutor, to deal with these difficulties should be emphasised.
Simplifications for hydronic system models in modelica
Jorissen, F.; Wetter, M.; Helsen, L.
2018-01-12
Building systems and their heating, ventilation and air conditioning flow networks, are becoming increasingly complex. Some building energy simulation tools simulate these flow networks using pressure drop equations. These flow network models typically generate coupled algebraic nonlinear systems of equations, which become increasingly more difficult to solve as their sizes increase. This leads to longer computation times and can cause the solver to fail. These problems also arise when using the equation-based modelling language Modelica and Annex 60-based libraries. This may limit the applicability of the library to relatively small problems unless problems are restructured. This paper discusses two algebraicmore » loop types and presents an approach that decouples algebraic loops into smaller parts, or removes them completely. The approach is applied to a case study model where an algebraic loop of 86 iteration variables is decoupled into smaller parts with a maximum of five iteration variables.« less
Modeling visual problem solving as analogical reasoning.
Lovett, Andrew; Forbus, Kenneth
2017-01-01
We present a computational model of visual problem solving, designed to solve problems from the Raven's Progressive Matrices intelligence test. The model builds on the claim that analogical reasoning lies at the heart of visual problem solving, and intelligence more broadly. Images are compared via structure mapping, aligning the common relational structure in 2 images to identify commonalities and differences. These commonalities or differences can themselves be reified and used as the input for future comparisons. When images fail to align, the model dynamically rerepresents them to facilitate the comparison. In our analysis, we find that the model matches adult human performance on the Standard Progressive Matrices test, and that problems which are difficult for the model are also difficult for people. Furthermore, we show that model operations involving abstraction and rerepresentation are particularly difficult for people, suggesting that these operations may be critical for performing visual problem solving, and reasoning more generally, at the highest level. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Professional Education and the Labor Market: Problems of Coordination
ERIC Educational Resources Information Center
Kochetov, A. N.
2012-01-01
The increasing desire to obtain a higher education in Russia is causing a growing disparity between educational qualifications and the needs of the labor market. Blue-collar jobs of varying levels are difficult to fill, and the demand for the qualification of those with degrees is not sufficient to avoid high levels of unemployment. Ways need to…
A Difficult, Confusing, Painful Problem That Requires Many Voices, Many Perceptions.
ERIC Educational Resources Information Center
Scheurich, James Joseph
1993-01-01
Responds to an article by Christine E. Sleeter (1993) and another by W.B. Allen (1993). Refutes criticisms that the author actually promotes racism in his call for increased white discourse on white racism and denies the individuality of races other than whites. However, personal individuality does not cancel the effects of inequality of power,…
ERIC Educational Resources Information Center
Omoregie, Harry O.
2012-01-01
In the last decade, the global information technology offshoring (ITO) and business process outsourcing (BPO) services have grown significantly, especially in Asia. The increased demand for offshore services in Asia has presented a difficult problem for U.S. organizations because countries such as India are now experiencing saturation of labor…
ERIC Educational Resources Information Center
Ecclestone, Kathryn
2012-01-01
It is difficult to challenge a strong consensus that governments must intervene in a worsening crisis of emotional and psychological well-being. The article relates rising estimates of problems and corresponding calls for intervention in educational settings to the increasingly blurred boundaries between a cultural therapeutic ethos, academic…
Everybody's Children: Child Care as a Public Problem.
ERIC Educational Resources Information Center
Gormley, William T., Jr.
In the face of social changes that are increasing the demand for available, affordable, quality child care, it is difficult to continue to think of child care as a purely private issue. This book presents an analysis of the state of American child care. It evaluates child care policies and the national attention given to young children and their…
Using Metadata To Improve Organization and Information Retrieval on the WWW.
ERIC Educational Resources Information Center
Doan, Bich-Lien; Beigbeder, Michel; Girardot, Jean-Jacques; Jaillon, Philippe
The growing volume of heterogeneous and distributed information on the World Wide Web has made it increasingly difficult for existing tools to retrieve relevant information. To improve the performance of these tools, this paper suggests how to handle two aspects of the problem. The first aspect concerns a better representation and description of…
Empirical Investigation of Job Applicants' Reactions to Taking a Pre-Employment Honesty Test.
ERIC Educational Resources Information Center
Jones, John W.; Joy, Dennis
Employee theft is widespread and difficult to detect. Many companies have attempted to control the employee theft problem through pre-employment screening. The use of paper-and-pencil honesty tests in this process has become increasingly common. These two studies empirically investigated job applicants' (N=450) reactions to taking a pre-employment…
ERIC Educational Resources Information Center
Watson, Silvana Maria Russo; Gable, Robert
2013-01-01
Adolescents face numerous challenges associated with increasing instructional curricular demands at the secondary level. Exacerbating an already difficult time for students with high-incidence disabilities (e.g., learning disabilities, emotional disabilities) is the fact that the majority spend at least some part of the day in general education…
ERIC Educational Resources Information Center
Munday, Jenni; Smith, Wyverne
2010-01-01
Pre-service teacher degree programs are increasingly crowded with subjects covering the wide gamut of knowledge a teacher requires. Ensuring musical knowledge and language for classroom teaching poses a difficult problem for teacher educators. This article examines the challenges of including in the pre-service classroom teaching program a music…
Evaluation of a Digital Learning Object for the Monty Hall Dilemma
ERIC Educational Resources Information Center
DiBattista, David
2011-01-01
The Monty Hall dilemma (MHD) is a remarkably difficult probability problem with a counterintuitive solution. Undergraduate students used an interactive digital learning object that provided a set-based, animated explanation of the solution to the MHD and let them play games designed to increase understanding of the solution. More than 60% of users…
Rosetta Structure Prediction as a Tool for Solving Difficult Molecular Replacement Problems.
DiMaio, Frank
2017-01-01
Molecular replacement (MR), a method for solving the crystallographic phase problem using phases derived from a model of the target structure, has proven extremely valuable, accounting for the vast majority of structures solved by X-ray crystallography. However, when the resolution of data is low, or the starting model is very dissimilar to the target protein, solving structures via molecular replacement may be very challenging. In recent years, protein structure prediction methodology has emerged as a powerful tool in model building and model refinement for difficult molecular replacement problems. This chapter describes some of the tools available in Rosetta for model building and model refinement specifically geared toward difficult molecular replacement cases.
Urban Mathematics Teacher Retention
ERIC Educational Resources Information Center
Hamdan, Kamal
2010-01-01
Mathematics teachers are both more difficult to attract and more difficult to retain than social sciences teachers. This fact is not unique to the United States; it is reported as being a problem in Europe as well (Howson, 2002). In the United States, however, the problem is particularly preoccupying. Because of the chronic teacher shortages and…
Baccalaureate Student Perceptions of Challenging Family Problems: Building Bridges to Acceptance
ERIC Educational Resources Information Center
Floyd, Melissa; Gruber, Kenneth J.
2011-01-01
This study explored the attitudes of 147 undergraduate social work majors to working with difficult families. Students indicated which problems (from a list of 42, including hot topics such as homosexuality, transgender issues, abortion, and substance abuse) they believed they would find most difficult to work with and provided information…
Drinkers and Bettors: Investigating the Complementarity of Alcohol Consumption and Problem Gambling
Maclean, Johanna Catherine; Ettner, Susan L.
2009-01-01
Regulated gambling is a multi-billion dollar industry in the United States with greater than 100 percent increases in revenue over the past decade. Along with this rise in gambling popularity and gaming options comes an increased risk of addiction and the associated social costs. This paper focuses on the effect of alcohol use on gambling-related problems. Variables correlated with both alcohol use and gambling may be difficult to observe, and the inability to include these items in empirical models may bias coefficient estimates. After addressing the endogeneity of alcohol use when appropriate, we find strong evidence that problematic gambling and alcohol consumption are complementary activities. PMID:18430523
Co-evolution for Problem Simplification
NASA Technical Reports Server (NTRS)
Haith, Gary L.; Lohn, Jason D.; Cplombano, Silvano P.; Stassinopoulos, Dimitris
1999-01-01
This paper explores a co-evolutionary approach applicable to difficult problems with limited failure/success performance feedback. Like familiar "predator-prey" frameworks this algorithm evolves two populations of individuals - the solutions (predators) and the problems (prey). The approach extends previous work by rewarding only the problems that match their difficulty to the level of solut,ion competence. In complex problem domains with limited feedback, this "tractability constraint" helps provide an adaptive fitness gradient that, effectively differentiates the candidate solutions. The algorithm generates selective pressure toward the evolution of increasingly competent solutions by rewarding solution generality and uniqueness and problem tractability and difficulty. Relative (inverse-fitness) and absolute (static objective function) approaches to evaluating problem difficulty are explored and discussed. On a simple control task, this co-evolutionary algorithm was found to have significant advantages over a genetic algorithm with either a static fitness function or a fitness function that changes on a hand-tuned schedule.
ERIC Educational Resources Information Center
Hill, George B.; Sweeney, Joseph B.
2015-01-01
Reaction workup can be a complex problem for those facing novel synthesis of difficult compounds for the first time. Workup problem solving by systematic thinking should be inculcated as mid-graduate-level is reached. A structured approach is proposed, building decision tree flowcharts to analyze challenges, and an exemplar flowchart is presented…
ERIC Educational Resources Information Center
van Veen, Saskia C.; de Wildt-Liesveld, Renée; Bunders, Joske F. G.; Regeer, Barbara J.
2014-01-01
Change processes are increasingly seen as the solution to entrenched (social) problems. However, change is difficult to realise while dealing with multiple actors, values, and approaches. (Inter)organisational learning is seen as a way to facilitate reflective practices in social change that support emergent changes, vicarious learning, and…
Web Accessibility in Europe and the United States: What We Are Doing to Increase Inclusion
ERIC Educational Resources Information Center
Wheaton, Joseph; Bertini, Patrizia
2007-01-01
Accessibility is hardly a new problem and certainly did not originate with the Web. Lack of access to buildings long preceded the call for accessible Web content. Although it is unlikely that rehabilitation educators look at Web page accessibility with indifference, many may also find it difficult to implement. The authors posit three reasons why…
NASA Astrophysics Data System (ADS)
Tapilouw, Marisa Christina; Firman, Harry; Redjeki, Sri; Chandra, Didi Teguh
2017-05-01
Teacher training is one form of continuous professional development. Before organizing teacher training (material, time frame), a survey about teacher's need has to be done. Science teacher's perception about science learning in the classroom, the most difficult learning model, difficulties of lesson plan would be a good input for teacher training program. This survey conducted in June 2016. About 23 science teacher filled in the questionnaire. The core of questions are training participation, the most difficult science subject matter, the most difficult learning model, the difficulties of making lesson plan, knowledge of integrated science and problem based learning. Mostly, experienced teacher participated training once a year. Science training is very important to enhance professional competency and to improve the way of teaching. The difficulties of subject matter depend on teacher's education background. The physics subject matter in class VIII and IX are difficult to teach for most respondent because of many formulas and abstract. Respondents found difficulties in making lesson plan, in term of choosing the right learning model for some subject matter. Based on the result, inquiry, cooperative, practice are frequently used in science class. Integrated science is understood as a mix between Biology, Physics and Chemistry concepts. On the other hand, respondents argue that problem based learning was difficult especially in finding contextual problem. All the questionnaire result can be used as an input for teacher training program in order to enhanced teacher's competency. Difficult concepts, integrated science, teaching plan, problem based learning can be shared in teacher training.
Caronia, Francesco Paolo; Fiorelli, Alfonso; Arrigo, Ettore; Santini, Mario; Castorina, Sergio
2016-05-01
Herein, we reported a catastrophic condition as the almost complete rupture of trachea associated with esophageal lesion following an urgent surgical tracheostomy performed for unexpected difficult intubation. The extent of lesions required a surgical management. We decided against a resection and an end to end anastomosis but preferred to perform a direct suture of the lesion due to the presence of local and systemic infection. Then, the diagnosis of a tracheal fistula led us to perform a direct suture of the defect that was covered with muscle flaps. Actually the patient is alive without problems. Emergency situations as unexpected airway difficult intubation increase morbidity and mortality rate of tracheostomy also in expert hands. Sometimes these events are unpredictable. Mastery with a number of advanced airway technique should be sought when faced dealing with unexpected difficult intubations and written consent of such a concern should be given to the patient.
Educational Reform as a Dynamic System of Problems and Solutions: Towards an Analytic Instrument
ERIC Educational Resources Information Center
Luttenberg, Johan; Carpay, Thérèse; Veugelers, Wiel
2013-01-01
Large-scale educational reforms are difficult to realize and often fail. In the literature, the course of reform and problems associated with this are frequently discussed. The explanations and recommendations then provided are so diverse that it is difficult to gain a comprehensive overview of what factors are at play and how to take them into…
ERIC Educational Resources Information Center
Albert, Lawrence S.
If being a competent small group problem solver is difficult, it is even more difficult to impart those competencies to others. Unlike athletic coaches who are near their players during the real game, teachers of small group communication are not typically present for on-the-spot coaching when their students are doing their problem solving. That…
Role of CT scanning in formation evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bergosh, J.L.; Dibona, B.G.
1988-01-01
The use of the computerized tomographic (CT) scanner in formation evaluation of difficult to analyze core samples has moved from the research and development phase to daily, routine use in the core-analysis laboratory. The role of the CT scanner has become increasingly important as geologists try to obtain more representative core material for accurate formation evaluation. The most common problem facing the core analyst when preparing to measure petrophysical properties is the selection of representative and unaltered core samples for routine and special core testing. Recent data have shown that heterogeneous reservoir rock can be very difficult, if not impossible,more » to assess correctly when using standard core examination procedures, because many features, such as fractures, are not visible on the core surface. Another problem is the invasion of drilling mud into the core sample. Flushing formation oil and water from the core can greatly alter the saturation and distribution of fluids and lead to serious formation evaluation problems. Because the quality and usefulness of the core date are directly tied to proper sample selection, it has become imperative that the CT scanner be used whenever possible.« less
Examining problem solving in physics-intensive Ph.D. research
NASA Astrophysics Data System (ADS)
Leak, Anne E.; Rothwell, Susan L.; Olivera, Javier; Zwickl, Benjamin; Vosburg, Jarrett; Martin, Kelly Norris
2017-12-01
Problem-solving strategies learned by physics undergraduates should prepare them for real-world contexts as they transition from students to professionals. Yet, graduate students in physics-intensive research face problems that go beyond problem sets they experienced as undergraduates and are solved by different strategies than are typically learned in undergraduate coursework. This paper expands the notion of problem solving by characterizing the breadth of problems and problem-solving processes carried out by graduate students in physics-intensive research. We conducted semi-structured interviews with ten graduate students to determine the routine, difficult, and important problems they engage in and problem-solving strategies they found useful in their research. A qualitative typological analysis resulted in the creation of a three-dimensional framework: context, activity, and feature (that made the problem challenging). Problem contexts extended beyond theory and mathematics to include interactions with lab equipment, data, software, and people. Important and difficult contexts blended social and technical skills. Routine problem activities were typically well defined (e.g., troubleshooting), while difficult and important ones were more open ended and had multiple solution paths (e.g., evaluating options). In addition to broadening our understanding of problems faced by graduate students, our findings explore problem-solving strategies (e.g., breaking down problems, evaluating options, using test cases or approximations) and characteristics of successful problem solvers (e.g., initiative, persistence, and motivation). Our research provides evidence of the influence that problems students are exposed to have on the strategies they use and learn. Using this evidence, we have developed a preliminary framework for exploring problems from the solver's perspective. This framework will be examined and refined in future work. Understanding problems graduate students face and the strategies they use has implications for improving how we approach problem solving in undergraduate physics and physics education research.
Teaching genetics using hands-on models, problem solving, and inquiry-based methods
NASA Astrophysics Data System (ADS)
Hoppe, Stephanie Ann
Teaching genetics can be challenging because of the difficulty of the content and misconceptions students might hold. This thesis focused on using hands-on model activities, problem solving, and inquiry-based teaching/learning methods in order to increase student understanding in an introductory biology class in the area of genetics. Various activities using these three methods were implemented into the classes to address any misconceptions and increase student learning of the difficult concepts. The activities that were implemented were shown to be successful based on pre-post assessment score comparison. The students were assessed on the subjects of inheritance patterns, meiosis, and protein synthesis and demonstrated growth in all of the areas. It was found that hands-on models, problem solving, and inquiry-based activities were more successful in learning concepts in genetics and the students were more engaged than tradition styles of lecture.
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.
International trade of U.S. hardwood lumber and logs, 1990-2013
William G. Luppold; Matthew S. Bumgardner
2014-01-01
United States (U.S.) hardwood log and lumber exports surged in the early- and mid-1970s in response to the adoption of floating exchange rates. However, assessing these changes in international trade became difficult in the 1980s due to increased underreporting of hardwood lumber and log shipments between the U.S. and Canada. By 1990, these data problems were rectified...
Special Course on Interaction of Propagation and Digital Transmission Techniques
1986-10-01
military roles. Many working systems have been demonstrated, and there are a number of fully operational civil systems, see for example (Western Union ...provided by the previous analogue systems, impose increased bandwidth demands which are difficult to fulfill in the spectrally-congested European...AGARD, 1984, "Propagation influences on digital transmission systems - problems and solutions", AGARD CP No.363. 2. Western Union
Bao, Peng; Jing, Jin; Jin, Yu; Hu, Xumin; Liu, Buyun; Hu, Min
2016-06-01
Since child mental health problem was a global health issue, many researchers in western countries has focused on the trajectory of it to provide evidence for prevention programs. We designed this study to determine the trajectories of children's behavior problems, and to explore the effect of parent predictors on children's behavior problems in Guangzhou, China. Children (N = 1480) for this longitudinal, population-based survey, were recruited from eight regular kindergartens (October, 2010) across four districts in Guangzhou. Repeated measurement design analysis was used to compare the variation in behavioral problems by gender, only child status, and temperament. Logistic regression was applied to analyze the effect of parents' risks (maternal depression, parenting style) on the change in child problem behaviors. The scores of behavior problems (externalizing, emotional, social communication problems) were stable during the entire preschool period by gender and child number. Children with difficult temperament exhibited more problem behaviors than children with easy temperament in the early years, and the misbehaviors declined significantly over time. Moreover, maternal depression and the increase in excessive interference/over protective or punishing parenting strategies resulted in an increase in child behavior problems. There was no difference between the only-child status and child with siblings in the trajectory of problem behaviors. Parent factors were significant predictions of trajectory of child behavior problem during preschool age.
[Personal resources and nursing work: a research on coping strategies and job satisfaction].
Formentin, Silvia; Dallago, Lorenza; Negrisolo, Adriana
2009-01-01
The coping (ability to face a difficult situation), is an essential resource for nurses, because it increases the effective functioning in the working environment, job satisfaction and individual level of wellness. The aim of this study is to explore the relationship between coping strategies and job satisfaction. A self report questionnaire was administered to all the nurses working in health services and hospitals of Padua province and to free lance nurses members of the College of Nurses, to collect information on coping strategies and job satisfaction. 2264 questionnaires were returned (71%). Active coping strategies are adopted mainly from older nurses while avoiding strategies are prevalent among younger. An association was observed between job satisfaction and active coping strategies, aimed at problem solving: active strategies increase job satisfaction while avoiding strategies descrease it. Individual coping strategies implemented to face difficult situations are associated to job satisfaction.
Probiotics and gastrointestinal disease: successes, problems and future prospects
2009-01-01
Gastrointestinal disease is a major cause of morbidity and mortality worldwide each year. Treatment of chronic inflammatory gastrointestinal conditions such as ulcerative colitis and Crohn's disease is difficult due to the ambiguity surrounding their precise aetiology. Infectious gastrointestinal diseases, such as various types of diarrheal disease are also becoming increasingly difficult to treat due to the increasing dissemination of antibiotic resistance among microorganisms and the emergence of the so-called 'superbugs'. Taking into consideration these problems, the need for novel therapeutics is essential. Although described for over a century probiotics have only been extensively researched in recent years. Their use in the treatment and prevention of disease, particularly gastrointestinal disease, has yielded many successful results, some of which we outline in this review. Although promising, many probiotics are hindered by inherent physiological and technological weaknesses and often the most clinically promising strains are unusable. Consequently we discuss various strategies whereby probiotics may be engineered to create designer probiotics. Such innovative approaches include; a receptor mimicry strategy to create probiotics that target specific pathogens and toxins, a patho-biotechnology approach using pathogen-derived genes to create more robust probiotic stains with increased host and processing-associated stress tolerance profiles and meta-biotechnology, whereby, functional metagenomics may be used to identify novel genes from diverse and vastly unexplored environments, such as the human gut, for use in biotechnology and medicine. PMID:19930635
Probiotics and gastrointestinal disease: successes, problems and future prospects.
Culligan, Eamonn P; Hill, Colin; Sleator, Roy D
2009-11-23
Gastrointestinal disease is a major cause of morbidity and mortality worldwide each year. Treatment of chronic inflammatory gastrointestinal conditions such as ulcerative colitis and Crohn's disease is difficult due to the ambiguity surrounding their precise aetiology. Infectious gastrointestinal diseases, such as various types of diarrheal disease are also becoming increasingly difficult to treat due to the increasing dissemination of antibiotic resistance among microorganisms and the emergence of the so-called 'superbugs'. Taking into consideration these problems, the need for novel therapeutics is essential. Although described for over a century probiotics have only been extensively researched in recent years. Their use in the treatment and prevention of disease, particularly gastrointestinal disease, has yielded many successful results, some of which we outline in this review. Although promising, many probiotics are hindered by inherent physiological and technological weaknesses and often the most clinically promising strains are unusable. Consequently we discuss various strategies whereby probiotics may be engineered to create designer probiotics. Such innovative approaches include; a receptor mimicry strategy to create probiotics that target specific pathogens and toxins, a patho-biotechnology approach using pathogen-derived genes to create more robust probiotic stains with increased host and processing-associated stress tolerance profiles and meta-biotechnology, whereby, functional metagenomics may be used to identify novel genes from diverse and vastly unexplored environments, such as the human gut, for use in biotechnology and medicine.
TEMPERAMENT, FAMILY ENVIRONMENT, AND BEHAVIOR PROBLEMS IN CHILDREN WITH NEW-ONSET SEIZURES
Baum, Katherine T.; Byars, Anna W.; deGrauw, Ton J.; Johnson, Cynthia S.; Perkins, Susan M.; Dunn, David W.; Bates, John E.; Austin, Joan K.
2007-01-01
Children with epilepsy, even those with new-onset seizures, exhibit relatively high rates of behavior problems. The purpose of this study was to explore the relationships among early temperament, family adaptive resources, and behavior problems in children with new-onset seizures. Our major goal was to test whether family adaptive resources moderated the relationship between early temperament dimensions and current behavior problems in 287 children with new-onset seizures. Two of the three temperament dimensions (difficultness and resistance to control) were positively correlated with total, internalizing, and externalizing behavior problems (all p < 0.0001). The third temperament dimension, unadaptability, was positively correlated with total and internalizing problems (p < 0.01). Family adaptive resources moderated the relationships between temperament and internalizing and externalizing behavior problems at school. Children with a difficult early temperament who live in a family environment with low family mastery are at the greatest risk for behavior problems. PMID:17267291
A study of fuzzy logic ensemble system performance on face recognition problem
NASA Astrophysics Data System (ADS)
Polyakova, A.; Lipinskiy, L.
2017-02-01
Some problems are difficult to solve by using a single intelligent information technology (IIT). The ensemble of the various data mining (DM) techniques is a set of models which are able to solve the problem by itself, but the combination of which allows increasing the efficiency of the system as a whole. Using the IIT ensembles can improve the reliability and efficiency of the final decision, since it emphasizes on the diversity of its components. The new method of the intellectual informational technology ensemble design is considered in this paper. It is based on the fuzzy logic and is designed to solve the classification and regression problems. The ensemble consists of several data mining algorithms: artificial neural network, support vector machine and decision trees. These algorithms and their ensemble have been tested by solving the face recognition problems. Principal components analysis (PCA) is used for feature selection.
ERIC Educational Resources Information Center
D'Andrea, Michael; Daniels, Judy
2007-01-01
The authors describe social justice advocacy interventions to initiate difficult discussions at the university where they are employed. They emphasize the need to foster difficult dialogues about the problem of institutional racism among students, faculty members, and administrators where they work. The Privileged Identity Exploration (PIE) model…
Anytime Prediction: Efficient Ensemble Methods for Any Computational Budget
2014-01-21
difficult problem and is the focus of this work. 1.1 Motivation The number of machine learning applications which involve real time and latency sensitive pre...significantly increasing latency , and the computational costs associated with hosting a service are often critical to its viability. For such...balancing training costs, concerns such as scalability and tractability are often more important, as opposed to factors such as latency which are more
Putting the Aero Back into Aeroelasticity
NASA Technical Reports Server (NTRS)
Bousman, William G.
2000-01-01
The lack of progress in understanding the physics of rotorcraft loads and vibration over the last 30 years is addressed in this paper. As befits this extraordinarily difficult problem, the reasons for the lack of progress are complicated and difficult to ascertain. It is proposed here that the difficulty lies within at least three areas: 1) a loss of perspective as to what are the key factors in rotor loads and vibration, 2) the overlooking of serious unsolved problems in the field, and 3) cultural barriers that impede progress. Some criteria are suggested for future research to provide a more concentrated focus on the problem.
Putting the Aero Back Into Aeroelasticity
NASA Technical Reports Server (NTRS)
Bousman, William G.; Aiken, Edwin W. (Technical Monitor)
1999-01-01
The lack of progress in understanding the physics of rotorcraft loads and vibration over the last 30 years is addressed in this paper. As befits this extraordinarily difficult problem, the reasons for the lack of progress are complicated and difficult to ascertain. It is proposed here that the difficulty lies within at least three areas: 1) a loss of perspective as to what are the key factors in rotor loads and vibration, 2) the overlooking of serious unsolved problems in the field, and 3) cultural barriers that impede progress. Some criteria are suggested for future research to provide a more concentrated focus on the problem.
The Difficult Stoma: Challenges and Strategies
Strong, Scott A.
2016-01-01
The problems that a patient experiences after the creation of a temporary or permanent stoma can result from many factors, but a carefully constructed stoma located in an ideal location is typically associated with appropriate function and an acceptable quality of life. The construction of the stoma can be confounded by many concomitant conditions that increase the distance that the bowel must traverse or shorten the bowel's capacity to reach. Stomas can be further troubled by a variety of problems that potentially arise early in the recovery period or months later. Surgeons must be familiar with these obstacles and complications to avoid their occurrence and minimize their impact. PMID:27247541
Information retrieval from holographic interferograms: Fundamentals and problems
NASA Technical Reports Server (NTRS)
Vest, Charles M.
1987-01-01
Holographic interferograms can contain large amounts of information about flow and temperature fields. Their information content can be very high because they can be viewed from many different directions. This multidirectionality, and fringe localization add to the information contained in the fringe pattern if diffuse illumination is used. Additional information, and increased accuracy can be obtained through the use of dual reference wave holography to add reference fringes or to effect discrete phase shift or hetrodyne interferometry. Automated analysis of fringes is possible if interferograms are of simple structure and good quality. However, in practice a large number of practical problems can arise, so that a difficult image processing task results.
Research and Implementation of Tibetan Word Segmentation Based on Syllable Methods
NASA Astrophysics Data System (ADS)
Jiang, Jing; Li, Yachao; Jiang, Tao; Yu, Hongzhi
2018-03-01
Tibetan word segmentation (TWS) is an important problem in Tibetan information processing, while abbreviated word recognition is one of the key and most difficult problems in TWS. Most of the existing methods of Tibetan abbreviated word recognition are rule-based approaches, which need vocabulary support. In this paper, we propose a method based on sequence tagging model for abbreviated word recognition, and then implement in TWS systems with sequence labeling models. The experimental results show that our abbreviated word recognition method is fast and effective and can be combined easily with the segmentation model. This significantly increases the effect of the Tibetan word segmentation.
Orthopaedic jack for scoliosis surgery purposes: Concept and design
NASA Astrophysics Data System (ADS)
Supriadi, Sugeng; Radhana, Rakha M.; Hidayanto, Taufik Eko; Whulanza, Yudan; Ali, Notario, Nanda; Rahyussalim
2017-02-01
Scoliosis surgery is one of the most difficult orthopedic surgery that have been committed today as the failure rate of orthopedic surgery for adult patients is 15%. Aside from the long duration of surgery, this surgical failure is caused by failure in biomedical instrumentation. Furthermore, this kind of failure is causing inefficiency of the surgery. With current known orthopedic surgery method, three surgeons are needed in a single orthopedic surgery. In fact, a single surgery can take up to 8 hours to be done, which increases the risk of surgical failure. Based on this problem, authors hope that our orthopedic jacks could solve the problem.
Zhang, H H; Gao, S; Chen, W; Shi, L; D'Souza, W D; Meyer, R R
2013-03-21
An important element of radiation treatment planning for cancer therapy is the selection of beam angles (out of all possible coplanar and non-coplanar angles in relation to the patient) in order to maximize the delivery of radiation to the tumor site and minimize radiation damage to nearby organs-at-risk. This category of combinatorial optimization problem is particularly difficult because direct evaluation of the quality of treatment corresponding to any proposed selection of beams requires the solution of a large-scale dose optimization problem involving many thousands of variables that represent doses delivered to volume elements (voxels) in the patient. However, if the quality of angle sets can be accurately estimated without expensive computation, a large number of angle sets can be considered, increasing the likelihood of identifying a very high quality set. Using a computationally efficient surrogate beam set evaluation procedure based on single-beam data extracted from plans employing equallyspaced beams (eplans), we have developed a global search metaheuristic process based on the nested partitions framework for this combinatorial optimization problem. The surrogate scoring mechanism allows us to assess thousands of beam set samples within a clinically acceptable time frame. Tests on difficult clinical cases demonstrate that the beam sets obtained via our method are of superior quality.
Zhang, H H; Gao, S; Chen, W; Shi, L; D’Souza, W D; Meyer, R R
2013-01-01
An important element of radiation treatment planning for cancer therapy is the selection of beam angles (out of all possible coplanar and non-coplanar angles in relation to the patient) in order to maximize the delivery of radiation to the tumor site and minimize radiation damage to nearby organs-at-risk. This category of combinatorial optimization problem is particularly difficult because direct evaluation of the quality of treatment corresponding to any proposed selection of beams requires the solution of a large-scale dose optimization problem involving many thousands of variables that represent doses delivered to volume elements (voxels) in the patient. However, if the quality of angle sets can be accurately estimated without expensive computation, a large number of angle sets can be considered, increasing the likelihood of identifying a very high quality set. Using a computationally efficient surrogate beam set evaluation procedure based on single-beam data extracted from plans employing equally-spaced beams (eplans), we have developed a global search metaheuristic process based on the Nested Partitions framework for this combinatorial optimization problem. The surrogate scoring mechanism allows us to assess thousands of beam set samples within a clinically acceptable time frame. Tests on difficult clinical cases demonstrate that the beam sets obtained via our method are superior quality. PMID:23459411
Efficient Credit Assignment through Evaluation Function Decomposition
NASA Technical Reports Server (NTRS)
Agogino, Adrian; Turner, Kagan; Mikkulainen, Risto
2005-01-01
Evolutionary methods are powerful tools in discovering solutions for difficult continuous tasks. When such a solution is encoded over multiple genes, a genetic algorithm faces the difficult credit assignment problem of evaluating how a single gene in a chromosome contributes to the full solution. Typically a single evaluation function is used for the entire chromosome, implicitly giving each gene in the chromosome the same evaluation. This method is inefficient because a gene will get credit for the contribution of all the other genes as well. Accurately measuring the fitness of individual genes in such a large search space requires many trials. This paper instead proposes turning this single complex search problem into a multi-agent search problem, where each agent has the simpler task of discovering a suitable gene. Gene-specific evaluation functions can then be created that have better theoretical properties than a single evaluation function over all genes. This method is tested in the difficult double-pole balancing problem, showing that agents using gene-specific evaluation functions can create a successful control policy in 20 percent fewer trials than the best existing genetic algorithms. The method is extended to more distributed problems, achieving 95 percent performance gains over tradition methods in the multi-rover domain.
Gender and rapid alterations of hemispheric dominance during planning.
Schuepbach, Daniel; Skotchko, Tatjana; Duschek, Stefan; Theodoridou, Anastasia; Grimm, Simone; Boeker, Heinz; Seifritz, Erich
2012-01-01
Mental planning and carrying out a plan provoke specific cerebral hemodynamic responses. Gender aspects of hemispheric laterality using rapid cerebral hemodynamics have not been reported. Here, we applied functional transcranial Doppler sonography to examine lateralization of cerebral hemodynamics of the middle cerebral arteries of 28 subjects (14 women and 14 men) performing a standard planning task. There were easy and difficult problems, and mental planning without motor activity was separated from movement execution. Difficult mental planning elicited lateralization to the right hemisphere after 2 or more seconds, a feature that was not observed during movement execution. In females, there was a dominance to the left hemisphere during movement execution. Optimized problem solving yielded an increased laterality change to the right during mental planning. Gender-related hemispheric dominance appears to be condition-dependent, and change of laterality to the right may play a role in optimized performance. Results are of relevance when considering laterality from a perspective of performance enhancement of higher cognitive functions, and also of psychiatric disorders with cognitive dysfunctions and abnormal lateralization patterns such as schizophrenia. Copyright © 2012 S. Karger AG, Basel.
Green PCB Remediation from Sediment Systems (GPRSS) Project
NASA Technical Reports Server (NTRS)
Falker, John; Thompson, Karen; Zeitlin, Nancy; Quinn, Jacqueline; Parrish, Lewis M.
2014-01-01
An ongoing problem facing the global environment community including NASA centers is the removal and remediation of polychlorinated biphenyls (PCBs). PCBs were commonly used in a variety of materials including paints, caulking, and adhesives due to the advantageous physical and chemical properties that PCBs imparted to these various materials. Unfortunately, these properties have made the treatment of sites contaminated with these chemicals extremely difficult to deal with, due to their inherent chemical stability. The remediation of sediments contaminated with PCBs is especially difficult, primarily due to the risk of releasing the contaminant into the environment during the treatment process. Traditional treatment options involve the use of dredging and incineration of the contaminated soils/sediments, in which the chance of releasing the contaminants is greatly increased. The purpose of this project is to develop cleanup technology capable of remediating contaminated sediments in-situ, with minimum intrusion. This allows for the minimization of any potential contaminant release during the treatment process, providing a safer method for cleanup operations (as opposed to dredging/incineration) and still treating the basic problem of PCB contamination (as opposed to capping).
[Quality assurance in airway management: education and training for difficult airway management].
Kaminoh, Yoshiroh
2006-01-01
Respiratory problem is one of the main causes of death or severe brain damage in perioperative period. Three major factors of respiratory problem are esophageal intubation, inadequate ventilation, and difficult airway. The wide spread of pulse oximeter and capnograph reduced the incidences of esophageal intubation and inadequate ventilation, but the difficult airway still occupies the large portion in the causes of adverse events during anesthesia. "Practice guideline for management of the difficult airway" was proposed by American Society of Anesthesiologists (ASA) in 1992 and 2002. Improvement of knowledge, technical skills, and cognitive skills are necessary for the education and training of the difficult airway management. "The practical seminar of difficult airway management (DAM practical seminar)" has been cosponsored by the Japanese Association of Medical Simulation (JAMS) in the 51 st and 52 nd annual meetings of Japanese Society of Anesthesiologists and the 24th annual meeting of Japanese Society for Clinical Anesthesia. The DAM practical seminar is composed of the lecture session for ASA difficult airway algorithm, the hands-on training session for technical skills, and the scenario-based training session for cognitive skills. Ninty six Japanese anesthesiologists have completed the DAM practical seminar in one year. "The DAM instructor course" should be immediately prepared to organize the seminar more frequently.
Drilling Regolith: Why Is It So Difficult?
NASA Astrophysics Data System (ADS)
Schmitt, H. H.
2017-10-01
The Apollo rotary percussive drill system penetrated the lunar regolith with reasonable efficiency; however, extraction of the drill core stem proved to be very difficult on all three missions. Retractable drill stem flutes may solve this problem.
A Review of the Pilot Backache Problem in the CH113 Labrador Helicopter
1985-12-01
and increasing the kyphosis may not, by itself, cause a higher incidence of backache. Based on the numerous reports of back pain and observa- tions...regular exer- cise Based on the symptoms identified in the questionnaire and the causes identified by other investigators, design principles for an...helicopter pilots and, the causes of helicopter induced backache. While the prevelnnce of backache is difficult to establish at any given time, consid
Practical advantages of evolutionary computation
NASA Astrophysics Data System (ADS)
Fogel, David B.
1997-10-01
Evolutionary computation is becoming a common technique for solving difficult, real-world problems in industry, medicine, and defense. This paper reviews some of the practical advantages to using evolutionary algorithms as compared with classic methods of optimization or artificial intelligence. Specific advantages include the flexibility of the procedures, as well as their ability to self-adapt the search for optimum solutions on the fly. As desktop computers increase in speed, the application of evolutionary algorithms will become routine.
Everyday beliefs about sources of advice for the parents of difficult children.
Sonuga-Barke, E J; Thompson, M; Balding, J
1993-01-01
Parents were asked which sources of advice families with difficult children should seek. The results suggested a similar hierarchy of agencies for both boys and girls with emotional and behavioural problems. Teachers, doctors, child psychiatrists and health visitors all received strong positive ratings, books about children with problems received moderate positive ratings, religious leaders received the strongest negative ratings and grandparents and friends received neutral ratings. Implications for service provision are discussed.
A child with a difficult airway: what do I do next?
Engelhardt, Thomas; Weiss, Markus
2012-06-01
Difficulties in pediatric airway management are common and continue to result in significant morbidity and mortality. This review reports on current concepts in approaching a child with a difficult airway. Routine airway management in healthy children with normal airways is simple in experienced hands. Mask ventilation (oxygenation) is always possible and tracheal intubation normally simple. However, transient hypoxia is common in these children usually due to unexpected anatomical and functional airway problems or failure to ventilate during rapid sequence induction. Anatomical airway problems (upper airway collapse and adenoid hypertrophy) and functional airway problems (laryngospasm, bronchospasm, insufficient depth of anesthesia and muscle rigidity, gastric hyperinflation, and alveolar collapse) require urgent recognition and treatment algorithms due to insufficient oxygen reserves. Early muscle paralysis and epinephrine administration aids resolution of these functional airway obstructions. Children with an 'impaired' normal (foreign body, allergy, and inflammation) or an expected difficult (scars, tumors, and congenital) airway require careful planning and expertise. Training in the recognition and management of these different situations as well as a suitably equipped anesthesia workstation and trained personnel are essential. The healthy child with an unexpected airway problem requires clear strategies. The 'impaired' normal pediatric airway may be handled by anesthetists experienced with children, whereas the expected difficult pediatric airway requires dedicated pediatric anesthesia specialist care and should only be managed in specialized centers.
NASA Astrophysics Data System (ADS)
Zhang, P. P.; Guo, Y.; Wang, B.
2017-05-01
The main problems in milling difficult-to-machine materials are the high cutting temperature and rapid tool wear. However it is impossible to investigate tool wear in machining. Tool wear and cutting chip formation are two of the most important representations for machining efficiency and quality. The purpose of this paper is to develop the model of tool wear with cutting chip formation (width of chip and radian of chip) on difficult-to-machine materials. Thereby tool wear is monitored by cutting chip formation. A milling experiment on the machining centre with three sets cutting parameters was performed to obtain chip formation and tool wear. The experimental results show that tool wear increases gradually along with cutting process. In contrast, width of chip and radian of chip decrease. The model is developed by fitting the experimental data and formula transformations. The most of monitored errors of tool wear by the chip formation are less than 10%. The smallest error is 0.2%. Overall errors by the radian of chip are less than the ones by the width of chip. It is new way to monitor and detect tool wear by cutting chip formation in milling difficult-to-machine materials.
ERIC Educational Resources Information Center
Silberman, Mel
Written for parents, this book discusses four steps for dealing with children's difficult behavior. The book is divided into two parts. Part 1, "The Building Blocks," discusses baseline perspectives parents need to establish in order to effectively deal with difficult behavior. Topics covered include: (1) parents' dual roles as caregivers and…
Parental corporal punishment predicts behavior problems in early childhood.
Mulvaney, Matthew K; Mebert, Carolyn J
2007-09-01
Using data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (Research Triangle Institute, 2002), this study examined the impact of corporal punishment (CP) on children's behavior problems. Longitudinal analyses were specified that controlled for covarying contextual and parenting variables and that partialed child effects. The results indicate that parental CP uniquely contributes to negative behavioral adjustment in children at both 36 months and at 1st grade, with the effects at the earlier age more pronounced in children with difficult temperaments. Parents and mental health professionals who work to modify children's negative behavior should be aware of the unique impact that CP likely plays in triggering and maintaining children's behavior problems. Broad-based family policies that reduce the use of this parenting behavior would potentially increase children's mental health and decrease the incidence of children's behavior problems. PsycINFO Database Record (c) 2007 APA, all rights reserved
Body image, media, and eating disorders.
Derenne, Jennifer L; Beresin, Eugene V
2006-01-01
Eating disorders, including obesity, are a major public health problem today. Throughout history, body image has been determined by various factors, including politics and media. Exposure to mass media (television, movies, magazines, Internet) is correlated with obesity and negative body image, which may lead to disordered eating. The authors attempt to explain the historical context of the problem and explore potential avenues for change. The authors review changes in ideal female body type throughout history, comment on current attitudes toward shape and weight in both men and women, and outline interventions aimed at increasing healthy habits and fostering self-esteem in youth. Throughout history, the ideal of beauty has been difficult to achieve and has been shaped by social context. Current mass media is ubiquitous and powerful, leading to increased body dissatisfaction among both men and women. Parents need to limit children's exposure to media, promote healthy eating and moderate physical activity, and encourage participation in activities that increase mastery and self-esteem. Funding for high-quality, visible advertising campaigns promoting healthy life styles may increase awareness.
Does More Public Health Spending Buy Better Health?
Sung, Jaesang; Honore, Peggy
2015-01-01
Background: In this article, we attempt to address a persistent question in the health policy literature: Does more public health spending buy better health? This is a difficult question to answer due to unobserved differences in public health across regions as well as the potential for an endogenous relationship between public health spending and public health outcomes. Methods: We take advantage of the unique way in which public health is funded in Georgia to avoid this endogeneity problem, using a twelve year panel dataset of Georgia county public health expenditures and outcomes in order to address the “unobservables” problem. Results: We find that increases in public health spending lead to increases in mortality by several different causes, including early deaths and heart disease deaths. We also find that increases in such spending leads to increases in morbidity from heart disease. Conclusions: Our results suggest that more public health funding may not always lead to improvements in health outcomes at the county level. PMID:28462255
NASA Technical Reports Server (NTRS)
Lippisch, Espenlaub
1922-01-01
Any one endeavoring to solve the problem of soaring flight is confronted not only by structural difficulties, but also by the often far more difficult aerodynamic problem of flight properties and efficiency, which can only be determined by experimenting with the finished glider.
Bicriteria Network Optimization Problem using Priority-based Genetic Algorithm
NASA Astrophysics Data System (ADS)
Gen, Mitsuo; Lin, Lin; Cheng, Runwei
Network optimization is being an increasingly important and fundamental issue in the fields such as engineering, computer science, operations research, transportation, telecommunication, decision support systems, manufacturing, and airline scheduling. In many applications, however, there are several criteria associated with traversing each edge of a network. For example, cost and flow measures are both important in the networks. As a result, there has been recent interest in solving Bicriteria Network Optimization Problem. The Bicriteria Network Optimization Problem is known a NP-hard. The efficient set of paths may be very large, possibly exponential in size. Thus the computational effort required to solve it can increase exponentially with the problem size in the worst case. In this paper, we propose a genetic algorithm (GA) approach used a priority-based chromosome for solving the bicriteria network optimization problem including maximum flow (MXF) model and minimum cost flow (MCF) model. The objective is to find the set of Pareto optimal solutions that give possible maximum flow with minimum cost. This paper also combines Adaptive Weight Approach (AWA) that utilizes some useful information from the current population to readjust weights for obtaining a search pressure toward a positive ideal point. Computer simulations show the several numerical experiments by using some difficult-to-solve network design problems, and show the effectiveness of the proposed method.
NASA Astrophysics Data System (ADS)
Pattke, Marco; Martin, Manuel; Voit, Michael
2017-05-01
Tracking people with cameras in public areas is common today. However with an increasing number of cameras it becomes harder and harder to view the data manually. Especially in safety critical areas automatic image exploitation could help to solve this problem. Setting up such a system can however be difficult because of its increased complexity. Sensor placement is critical to ensure that people are detected and tracked reliably. We try to solve this problem using a simulation framework that is able to simulate different camera setups in the desired environment including animated characters. We combine this framework with our self developed distributed and scalable system for people tracking to test its effectiveness and can show the results of the tracking system in real time in the simulated environment.
Hatt, Sarah R; Leske, David A; Wernimont, Suzanne M; Birch, Eileen E; Holmes, Jonathan M
2017-03-01
A rating scale is a critical component of patient-reported outcome instrument design, but the optimal rating scale format for pediatric use has not been investigated. We compared rating scale performance when administering potential questionnaire items to children with eye disorders and their parents. Three commonly used rating scales were evaluated: frequency (never, sometimes, often, always), severity (not at all, a little, some, a lot), and difficulty (not difficult, a little difficult, difficult, very difficult). Ten patient-derived items were formatted for each rating scale, and rating scale testing order was randomized. Both child and parent were asked to comment on any problems with, or a preference for, a particular scale. Any confusion about options or inability to answer was recorded. Twenty-one children, aged 5-17 years, with strabismus, amblyopia, or refractive error were recruited, each with one of their parents. Of the first 10 children, 4 (40%) had problems using the difficulty scale, compared with 1 (10%) using frequency, and none using severity. The difficulty scale was modified, replacing the word "difficult" with "hard." Eleven additional children (plus parents) then completed all 3 questionnaires. No children had problems using any scale. Four (36%) parents had problems using the difficulty ("hard") scale and 1 (9%) with frequency. Regarding preference, 6 (55%) of 11 children and 5 (50%) of 10 parents preferred using the frequency scale. Children and parents found the frequency scale and question format to be the most easily understood. Children and parents also expressed preference for the frequency scale, compared with the difficulty and severity scales. We recommend frequency rating scales for patient-reported outcome measures in pediatric populations.
Focus group discussion in mathematical physics learning
NASA Astrophysics Data System (ADS)
Ellianawati; Rudiana, D.; Sabandar, J.; Subali, B.
2018-03-01
The Focus Group Discussion (FGD) activity in Mathematical Physics learning has helped students perform the stages of problem solving reflectively. The FGD implementation was conducted to explore the problems and find the right strategy to improve the students' ability to solve the problem accurately which is one of reflective thinking component that has been difficult to improve. The research method used is descriptive qualitative by using single subject response in Physics student. During the FGD process, one student was observed of her reflective thinking development in solving the physics problem. The strategy chosen in the discussion activity was the Cognitive Apprenticeship-Instruction (CA-I) syntax. Based on the results of this study, it is obtained the information that after going through a series of stages of discussion, the students' reflective thinking skills is increased significantly. The scaffolding stage in the CA-I model plays an important role in the process of solving physics problems accurately. Students are able to recognize and formulate problems by describing problem sketches, identifying the variables involved, applying mathematical equations that accord to physics concepts, executing accurately, and applying evaluation by explaining the solution to various contexts.
ERIC Educational Resources Information Center
Kelly, Ronald R.
2003-01-01
Presents "Project Solve," a web-based problem-solving instruction and guided practice for mathematical word problems. Discusses implications for college students for whom reading and comprehension of mathematical word problem solving are difficult, especially learning disabled students. (Author/KHR)
ERIC Educational Resources Information Center
Kolata, Gina
1985-01-01
To determine how hard it is for computers to solve problems, researchers have classified groups of problems (polynomial hierarchy) according to how much time they seem to require for their solutions. A difficult and complex proof is offered which shows that a combinatorial approach (using Boolean circuits) may resolve the problem. (JN)
ERIC Educational Resources Information Center
Quinn, Diane M.; Spencer, Steven J.
2001-01-01
Investigated whether stereotype threat would depress college women's math performance. In one test, men outperformed women when solving word problems, though women performed equally when problems were converted into numerical equivalents. In another test, participants solved difficult problems in high or reduced stereotype threat conditions. Women…
The Role of Expository Writing in Mathematical Problem Solving
ERIC Educational Resources Information Center
Craig, Tracy S.
2016-01-01
Mathematical problem-solving is notoriously difficult to teach in a standard university mathematics classroom. The project on which this article reports aimed to investigate the effect of the writing of explanatory strategies in the context of mathematical problem solving on problem-solving behaviour. This article serves to describe the…
Using KIE To Help Students Develop Shared Criteria for House Designs.
ERIC Educational Resources Information Center
Cuthbert, Alex; Hoadley, Christopher M.
How can students develop shared criteria for problems that have no "right" answer? Ill-structured problems of this sort are called design problems. Like portfolio projects, these problems are difficult to evaluate for both teachers and students. This investigation contrasts two methods for developing shared criteria for project…
Virtual Laboratories to Achieve Higher-Order Learning in Fluid Mechanics
NASA Astrophysics Data System (ADS)
Ward, A. S.; Gooseff, M. N.; Toto, R.
2009-12-01
Bloom’s higher-order cognitive skills (analysis, evaluation, and synthesis) are recognized as necessary in engineering education, yet these are difficult to achieve in traditional lecture formats. Laboratory components supplement traditional lectures in an effort to emphasize active learning and provide higher-order challenges, but these laboratories are often subject to the constraints of (a) increasing student enrollment, (b) limited funding for operational, maintenance, and instructional expenses and (c) increasing demands on undergraduate student credit requirements. Here, we present results from a pilot project implementing virtual (or online) laboratory experiences as an alternative to a traditional laboratory experience in Fluid Mechanics, a required third year course. Students and faculty were surveyed to identify the topics that were most difficult, and virtual laboratory and design components developed to supplement lecture material. Each laboratory includes a traditional lab component, requiring student analysis and evaluation. The lab concludes with a design exercise, which imposes additional problem constraints and allows students to apply their laboratory observations to a real-world situation.
ERIC Educational Resources Information Center
Waters, W. G., II
1973-01-01
Analyzes the urban transport problems in comparison with those involved in a journey to the Moon. Indicates that the problem of enabling man to travel through the inner space of conurbations may prove to be more difficult than the transport problem of space travel. (CC)
"But You Look So Good!": Managing Specific Issues
... and resources about handling bladder or bowel problems. Self-esteem “I think the most difficult thing to cope ... feel. It’s understandable then that MS can impact self-esteem and confidence. “It’s difficult to feel powerful, competent, ...
Use of Photovoice in addiction.
Miller Heery, Gretchen Hope
2013-09-01
The addiction to narcotic substances is an increasing public health problem. Addiction relapse is preventable. Photovoice may increase the success rate by offering a deeper perspective, insight, dimension of feeling, and perception connecting with those who feel disconnected. This process uses cameras, discussion groups, storyboards, and interaction to thread through difficult discussion points created by the participant. Understanding the process of recovery from opioid substance abuse creates an opportunity to maintain socially acceptable behaviors and decreases the risk of participating in illegal activities and making poor choices. Photovoice allows for creative expression of thought by bypassing cognitive defenses. Copyright © 2013 Elsevier Inc. All rights reserved.
Zinc Bromide Flow Battery Installation for Islanding and Backup Power
2017-08-09
predictably is in place. The ability to control generation has become more difficult with the increase of RE systems such as solar PV and wind turbines ...Both PV and wind systems generate power based on unpredictable cycles of nature. At very low levels of RE penetration the grid can be balanced by...Page Intentionally Left Blank 15 5.0 TEST DESIGN This goal of this demonstration was to solve two main problems . The first
Substance abuse and dependence in the hospital workplace: detection and handling.
Ossi, J
1991-01-01
A hospital can take many avenues in dealing with an employee or professional who is impaired by substance abuse or dependence. The most difficult aspect of dealing with the problem is detection. Fortunately, increasing public awareness and concern regarding workplace substance abuse is forcing legislators to address the issue and expose the problem. The legislative response appears to be geared toward treatment and education rather than punishment, which in the opinion of this author is a desirable approach. The pharmacy department can be a valuable asset to the hospital risk manager in detecting diversion of controlled substances and educating employees as to the clinical signs and symptoms of impairment.
NASA Astrophysics Data System (ADS)
Hasanah, N.; Hayashi, Y.; Hirashima, T.
2017-02-01
Arithmetic word problems remain one of the most difficult area of teaching mathematics. Learning by problem posing has been suggested as an effective way to improve students’ understanding. However, the practice in usual classroom is difficult due to extra time needed for assessment and giving feedback to students’ posed problems. To address this issue, we have developed a tablet PC software named Monsakun for learning by posing arithmetic word problems based on Triplet Structure Model. It uses the mechanism of sentence-integration, an efficient implementation of problem-posing that enables agent-assessment of posed problems. The learning environment has been used in actual Japanese elementary school classrooms and the effectiveness has been confirmed in previous researches. In this study, ten Indonesian elementary school students living in Japan participated in a learning session of problem posing using Monsakun in Indonesian language. We analyzed their learning activities and show that students were able to interact with the structure of simple word problem using this learning environment. The results of data analysis and questionnaire suggested that the use of Monsakun provides a way of creating an interactive and fun environment for learning by problem posing for Indonesian elementary school students.
Improving socket design to prevent difficult removal of locking screws.
Lin, Chen-Huei; Chao, Ching-Kong; Tang, Yi-Hsuan; Lin, Jinn
2018-03-01
Reports of driver slippage leading to difficult locking screw removals have increased since the adoption of titanium for screw fabrication; the use of titanium is known to cause cross-threading and cold welding. Such problems occur most frequently in screws with hex sockets, and may cause serious surgical complications. This study aimed to improve screw socket design to prevent slippage and difficult screw removal. Three types of small sockets (hex, Torx, and cruciate) and six types of large sockets (hex, Torx, Octatorx, Torx+ I, Torx+ II, and Torx+ III) with screw head diameters of 5.5 mm were manufactured from titanium, and corresponding screwdrivers were manufactured from stainless steel. The screw heads and drivers were mounted on a material testing machine, and torsional tests were conducted to simulate screw usage in clinical settings at two insertion depths: 1 and 2 mm. Ten specimens were tested from each design, and the maximum torque and failure patterns were recorded and compared. For small sockets in 2 mm conditions, the hex with the largest driver core had the highest torque, followed by Torx and cruciate. In these tests, the drivers were twisted off in all specimens. However, under the 1 mm condition, the hex slipped and the torque decreased markedly. Overall, torque was higher for large sockets than for small sockets. The Octatorx, with a large core and simultaneous deformation of the driver and socket lobes, had the highest torque at almost twice that of the small hex. The hex had the lowest torque, a result of slippage in both the 1 and 2 mm conditions. Torx plus designs, with more designed degrees of freedom, were able to maintain a higher driving angle and larger core for higher torque. The hex design showed slipping tendencies with a marked decrease in torque, especially under conditions with inadequate driver engagement. Large sockets allowed for substantial increases in torque. The Torx, Octatorx, and Torx plus designs displayed better performance than the hexes. Improvements to the socket design could effectively prevent slippage and solve difficult screw removal problems. Copyright © 2018. Published by Elsevier Ltd.
Supersonic reacting internal flowfields
NASA Astrophysics Data System (ADS)
Drummond, J. P.
The national program to develop a trans-atmospheric vehicle has kindled a renewed interest in the modeling of supersonic reacting flows. A supersonic combustion ramjet, or scramjet, has been proposed to provide the propulsion system for this vehicle. The development of computational techniques for modeling supersonic reacting flowfields, and the application of these techniques to an increasingly difficult set of combustion problems are studied. Since the scramjet problem has been largely responsible for motivating this computational work, a brief history is given of hypersonic vehicles and their propulsion systems. A discussion is also given of some early modeling efforts applied to high speed reacting flows. Current activities to develop accurate and efficient algorithms and improved physical models for modeling supersonic combustion is then discussed. Some new problems where computer codes based on these algorithms and models are being applied are described.
NASA Astrophysics Data System (ADS)
Dou, Hao; Sun, Xiao; Li, Bin; Deng, Qianqian; Yang, Xubo; Liu, Di; Tian, Jinwen
2018-03-01
Aircraft detection from very high resolution remote sensing images, has gained more increasing interest in recent years due to the successful civil and military applications. However, several problems still exist: 1) how to extract the high-level features of aircraft; 2) locating objects within such a large image is difficult and time consuming; 3) A common problem of multiple resolutions of satellite images still exists. In this paper, inspirited by biological visual mechanism, the fusion detection framework is proposed, which fusing the top-down visual mechanism (deep CNN model) and bottom-up visual mechanism (GBVS) to detect aircraft. Besides, we use multi-scale training method for deep CNN model to solve the problem of multiple resolutions. Experimental results demonstrate that our method can achieve a better detection result than the other methods.
Supersonic reacting internal flow fields
NASA Technical Reports Server (NTRS)
Drummond, J. Philip
1989-01-01
The national program to develop a trans-atmospheric vehicle has kindled a renewed interest in the modeling of supersonic reacting flows. A supersonic combustion ramjet, or scramjet, has been proposed to provide the propulsion system for this vehicle. The development of computational techniques for modeling supersonic reacting flow fields, and the application of these techniques to an increasingly difficult set of combustion problems are studied. Since the scramjet problem has been largely responsible for motivating this computational work, a brief history is given of hypersonic vehicles and their propulsion systems. A discussion is also given of some early modeling efforts applied to high speed reacting flows. Current activities to develop accurate and efficient algorithms and improved physical models for modeling supersonic combustion is then discussed. Some new problems where computer codes based on these algorithms and models are being applied are described.
The Efficacy of Using Diagrams When Solving Probability Word Problems in College
ERIC Educational Resources Information Center
Beitzel, Brian D.; Staley, Richard K.
2015-01-01
Previous experiments have shown a deleterious effect of visual representations on college students' ability to solve total- and joint-probability word problems. The present experiments used conditional-probability problems, known to be more difficult than total- and joint-probability problems. The diagram group was instructed in how to use tree…
The Development, Implementation, and Evaluation of a Problem Solving Heuristic
ERIC Educational Resources Information Center
Lorenzo, Mercedes
2005-01-01
Problem-solving is one of the main goals in science teaching and is something many students find difficult. This research reports on the development, implementation and evaluation of a problem-solving heuristic. This heuristic intends to help students to understand the steps involved in problem solving (metacognitive tool), and to provide them…
Procedural versus Content-Related Hints for Word Problem Solving: An Exploratory Study
ERIC Educational Resources Information Center
Kock, W. D.; Harskamp, E. G.
2016-01-01
For primary school students, mathematical word problems are often more difficult to solve than straightforward number problems. Word problems require reading and analysis skills, and in order to explain their situational contexts, the proper mathematical knowledge and number operations have to be selected. To improve students' ability in solving…
The Difficult Patron Situation: A Window of Opportunity To Improve Library Service.
ERIC Educational Resources Information Center
Sarkodie-Mensah, Kwasi
2000-01-01
Discusses the problem library patron from various fronts: historical, personality traits, importance of complaints, nature and types of problem patrons and their behavior, technology and the newly-bred problem patron, strategies for dealing with problem patrons, and ensuring that library administrators and other supervisors understand the need to…
Multidimensional Functional Behaviour Assessment within a Problem Analysis Framework.
ERIC Educational Resources Information Center
Ryba, Ken; Annan, Jean
This paper presents a new approach to contextualized problem analysis developed for use with multimodal Functional Behaviour Assessment (FBA) at Massey University in Auckland, New Zealand. The aim of problem analysis is to simplify complex problems that are difficult to understand. It accomplishes this by providing a high order framework that can…
Crisis management during anaesthesia: difficult intubation.
Paix, A D; Williamson, J A; Runciman, W B
2005-06-01
Anaesthetists may experience difficulty with intubation unexpectedly which may be associated with difficulty in ventilating the patient. If not well managed, there may be serious consequences for the patient. A simple structured approach to this problem was developed to assist the anaesthetist in this difficult situation. To examine the role of a specific sub-algorithm for the management of difficult intubation. The potential performance of a structured approach developed by review of the literature and analysis of each of the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved. There were 147 reports of difficult intubation capable of analysis among the first 4000 incidents reported to AIMS. The difficulty was unexpected in 52% of cases; major physiological changes occurred in 37% of these cases. Saturation fell below 90% in 22% of cases, oesophageal intubation was reported in 19%, and an emergency transtracheal airway was required in 4% of cases. Obesity and limited neck mobility and mouth opening were the most common anatomical contributing factors. The data confirm previously reported failures to predict difficult intubation with existing preoperative clinical tests and suggest an ongoing need to teach a pre-learned strategy to deal with difficult intubation and any associated problem with ventilation. An easy-to-follow structured approach to these problems is outlined. It is recommended that skilled assistance be obtained (preferably another anaesthetist) when difficulty is expected or the patient's cardiorespiratory reserve is low. Patients should be assessed postoperatively to exclude any sequelae and to inform them of the difficulties encountered. These should be clearly documented and appropriate steps taken to warn future anaesthetists.
A Cascade Optimization Strategy for Solution of Difficult Multidisciplinary Design Problems
NASA Technical Reports Server (NTRS)
Patnaik, Surya N.; Coroneos, Rula M.; Hopkins, Dale A.; Berke, Laszlo
1996-01-01
A research project to comparatively evaluate 10 nonlinear optimization algorithms was recently completed. A conclusion was that no single optimizer could successfully solve all 40 problems in the test bed, even though most optimizers successfully solved at least one-third of the problems. We realized that improved search directions and step lengths, available in the 10 optimizers compared, were not likely to alleviate the convergence difficulties. For the solution of those difficult problems we have devised an alternative approach called cascade optimization strategy. The cascade strategy uses several optimizers, one followed by another in a specified sequence, to solve a problem. A pseudorandom scheme perturbs design variables between the optimizers. The cascade strategy has been tested successfully in the design of supersonic and subsonic aircraft configurations and air-breathing engines for high-speed civil transport applications. These problems could not be successfully solved by an individual optimizer. The cascade optimization strategy, however, generated feasible optimum solutions for both aircraft and engine problems. This paper presents the cascade strategy and solutions to a number of these problems.
Shapiro, Johanna; Rakhra, Pavandeep; Wong, Adrianne
2016-10-01
Physicians have long had patients whom they have labeled "difficult", but little is known about how medical students perceive difficult encounters with patients. In this study, we analyzed 134 third year medical students' reflective essays written over an 18-month period about difficult student-patient encounters. We used a qualitative computerized software program, Atlas.ti to analyze students' observations and reflections. Main findings include that students described patients who were angry and upset; noncompliant with treatment plans; discussed "nonmedical" problems; fearful, worried, withdrawn, or "disinterested" in their health. Students often described themselves as anxious, uncertain, confused, and frustrated. Nevertheless, they saw themselves behaving in empathic and patient-centered ways while also taking refuge in "standard" behaviors not necessarily appropriate to the circumstances. Students rarely mentioned receiving guidance from attendings regarding how to manage these challenging interactions. These third-year medical students recognized the importance of behaving empathically in difficult situations and often did so. However, they often felt overwhelmed and frustrated, resorting to more reductive behaviors that did not match the needs of the patient. Students need more guidance from attending physicians in order to approach difficult interactions with specific problem-solving skills while maintaining an empathic, patient-centered context.
Frnakenstein: multiple target inverse RNA folding.
Lyngsø, Rune B; Anderson, James W J; Sizikova, Elena; Badugu, Amarendra; Hyland, Tomas; Hein, Jotun
2012-10-09
RNA secondary structure prediction, or folding, is a classic problem in bioinformatics: given a sequence of nucleotides, the aim is to predict the base pairs formed in its three dimensional conformation. The inverse problem of designing a sequence folding into a particular target structure has only more recently received notable interest. With a growing appreciation and understanding of the functional and structural properties of RNA motifs, and a growing interest in utilising biomolecules in nano-scale designs, the interest in the inverse RNA folding problem is bound to increase. However, whereas the RNA folding problem from an algorithmic viewpoint has an elegant and efficient solution, the inverse RNA folding problem appears to be hard. In this paper we present a genetic algorithm approach to solve the inverse folding problem. The main aims of the development was to address the hitherto mostly ignored extension of solving the inverse folding problem, the multi-target inverse folding problem, while simultaneously designing a method with superior performance when measured on the quality of designed sequences. The genetic algorithm has been implemented as a Python program called Frnakenstein. It was benchmarked against four existing methods and several data sets totalling 769 real and predicted single structure targets, and on 292 two structure targets. It performed as well as or better at finding sequences which folded in silico into the target structure than all existing methods, without the heavy bias towards CG base pairs that was observed for all other top performing methods. On the two structure targets it also performed well, generating a perfect design for about 80% of the targets. Our method illustrates that successful designs for the inverse RNA folding problem does not necessarily have to rely on heavy biases in base pair and unpaired base distributions. The design problem seems to become more difficult on larger structures when the target structures are real structures, while no deterioration was observed for predicted structures. Design for two structure targets is considerably more difficult, but far from impossible, demonstrating the feasibility of automated design of artificial riboswitches. The Python implementation is available at http://www.stats.ox.ac.uk/research/genome/software/frnakenstein.
Frnakenstein: multiple target inverse RNA folding
2012-01-01
Background RNA secondary structure prediction, or folding, is a classic problem in bioinformatics: given a sequence of nucleotides, the aim is to predict the base pairs formed in its three dimensional conformation. The inverse problem of designing a sequence folding into a particular target structure has only more recently received notable interest. With a growing appreciation and understanding of the functional and structural properties of RNA motifs, and a growing interest in utilising biomolecules in nano-scale designs, the interest in the inverse RNA folding problem is bound to increase. However, whereas the RNA folding problem from an algorithmic viewpoint has an elegant and efficient solution, the inverse RNA folding problem appears to be hard. Results In this paper we present a genetic algorithm approach to solve the inverse folding problem. The main aims of the development was to address the hitherto mostly ignored extension of solving the inverse folding problem, the multi-target inverse folding problem, while simultaneously designing a method with superior performance when measured on the quality of designed sequences. The genetic algorithm has been implemented as a Python program called Frnakenstein. It was benchmarked against four existing methods and several data sets totalling 769 real and predicted single structure targets, and on 292 two structure targets. It performed as well as or better at finding sequences which folded in silico into the target structure than all existing methods, without the heavy bias towards CG base pairs that was observed for all other top performing methods. On the two structure targets it also performed well, generating a perfect design for about 80% of the targets. Conclusions Our method illustrates that successful designs for the inverse RNA folding problem does not necessarily have to rely on heavy biases in base pair and unpaired base distributions. The design problem seems to become more difficult on larger structures when the target structures are real structures, while no deterioration was observed for predicted structures. Design for two structure targets is considerably more difficult, but far from impossible, demonstrating the feasibility of automated design of artificial riboswitches. The Python implementation is available at http://www.stats.ox.ac.uk/research/genome/software/frnakenstein. PMID:23043260
Transboundary environmental assessment: lessons from OTAG. The Ozone Transport Assessment Group.
Farrell, Alexander E; Keating, Terry J
2002-06-15
The nature and role of assessments in creating policy for transboundary environmental problems is discussed. Transboundary environmental problems are particularly difficult to deal with because they typically require cooperation among independent political jurisdictions (e.g., states or nations) which face differing costs and benefits and which often have different technical capabilities and different interests. In particular, transboundary pollution issues generally involve the problem of an upstream source and a downstream receptor on opposite sides of a relevant political boundary, making it difficult for the jurisdiction containing the receptor to obtain relief from the pollution problem. The Ozone Transport Assessment Group (OTAG) addressed such a transboundary problem: the long-range transport of tropospheric ozone (i.e., photochemical smog) across the eastern United States. The evolution of the science and policy that led to OTAG, the OTAG process, and its outcomes are presented. Lessons that are available to be learned from the OTAG experience, particularly for addressing similar transboundary problems such as regional haze, are discussed.
SYNTHESIS REPORT ON FIVE DENSE, NONAQUEOUS-PHASE LIQUID (DNAPL) REMEDIATION PROJECTS
Dense non-aqueous phase liquid (DNAPL) poses a difficult problem for subsurface remediation because it serves as a continuing source to dissolved phase ground water contamination and is difficult to remove from interstitial pore space or bedrock fractures in the subsurface. Numer...
Patients with difficult intubation may need referral to sleep clinics.
Chung, Frances; Yegneswaran, Balaji; Herrera, Francisco; Shenderey, Alex; Shapiro, Colin M
2008-09-01
Upper airway abnormalities carry the risk of obstructive sleep apnea (OSA) and difficult tracheal intubations. Both conditions contribute to significant clinical problems and have increased perioperative morbidity and mortality. We hypothesized that patients who presented with difficult intubation would have a very high prevalence of OSA and that those with unexpected difficult intubation may require referral to sleep clinics for polysomnography (PSG). Patients classified as a grade 4 Cormack and Lehane on direct laryngoscopic view, and who required more than two attempts for successful endotracheal intubation, were referred to the study by consultant anesthesiologists at four hospitals. Apnea-hypopnea index (AHI) data and postoperative events were collected. Patients with AHI >5/h were considered positive for OSA. Clinical and PSG variables were compared using t-tests and chi(2) test. Over a 20-mo period, 84 patients with a difficult intubation were referred into the study. Thirty-three patients agreed to participate. Sixty-six percent (22 of 33) had OSA (AHI >5/h). Of the 22 OSA patients, 10 patients (64%) had mild OSA (AHI 5-15), 6 (18%) had moderate OSA (AHI >15/h), and 6 (18%) had severe OSA (AHI >30/h). Of the 33 patients, 11 patients (33%) were recommended for continuous positive airway pressure treatment. Between the OSA group and the non-OSA group, there were significant differences in gender, neck size, and the quality of sleep, but there were no significant differences in age and body mass index. Sixty-six percent of patients with unexpected difficult intubation who consented to undergo a sleep study were diagnosed with OSA by PSG. Patients with difficult intubation are at high risk for OSA and should be screened for signs and symptoms of sleep apnea. Screening for OSA should be considered by referral to a sleep clinic for PSG.
Ertekin Pinar, Sukran; Yildirim, Gulay; Sayin, Neslihan
2018-05-01
The high level of psychological resilience, self-confidence and problem solving skills of midwife candidates play an important role in increasing the quality of health care and in fulfilling their responsibilities towards patients. This study was conducted to investigate the psychological resilience, self-confidence and problem-solving skills of midwife candidates. It is a convenience descriptive quantitative study. Students who study at Health Sciences Faculty in Turkey's Central Anatolia Region. Midwife candidates (N = 270). In collection of data, the Personal Information Form, Psychological Resilience Scale for Adults (PRSA), Self-Confidence Scale (SCS), and Problem Solving Inventory (PSI) were used. There was a negatively moderate-level significant relationship between the Problem Solving Inventory scores and the Psychological Resilience Scale for Adults scores (r = -0.619; p = 0.000), and between Self-Confidence Scale scores (r = -0.524; p = 0.000). There was a positively moderate-level significant relationship between the Psychological Resilience Scale for Adults scores and the Self-Confidence Scale scores (r = 0.583; p = 0.000). There was a statistically significant difference (p < 0.05) between the Problem Solving Inventory and the Psychological Resilience Scale for Adults scores according to getting support in a difficult situation. As psychological resilience and self-confidence levels increase, problem-solving skills increase; additionally, as self-confidence increases, psychological resilience increases too. Psychological resilience, self-confidence, and problem-solving skills of midwife candidates in their first-year of studies are higher than those who are in their fourth year. Self-confidence and psychological resilience of midwife candidates aged between 17 and 21, self-confidence and problem solving skills of residents of city centers, psychological resilience of those who perceive their monthly income as sufficient are high. Psychological resilience and problem-solving skills for midwife candidates who receive social support are also high. The fact that levels of self-confidence, problem-solving skills and psychological resilience of fourth-year students are found to be low presents a situation that should be taken into consideration. Copyright © 2018 Elsevier Ltd. All rights reserved.
Hartmann, Klaas; Steel, Mike
2006-08-01
The Noah's Ark Problem (NAP) is a comprehensive cost-effectiveness methodology for biodiversity conservation that was introduced by Weitzman (1998) and utilizes the phylogenetic tree containing the taxa of interest to assess biodiversity. Given a set of taxa, each of which has a particular survival probability that can be increased at some cost, the NAP seeks to allocate limited funds to conserving these taxa so that the future expected biodiversity is maximized. Finding optimal solutions using this framework is a computationally difficult problem to which a simple and efficient "greedy" algorithm has been proposed in the literature and applied to conservation problems. We show that, although algorithms of this type cannot produce optimal solutions for the general NAP, there are two restricted scenarios of the NAP for which a greedy algorithm is guaranteed to produce optimal solutions. The first scenario requires the taxa to have equal conservation cost; the second scenario requires an ultrametric tree. The NAP assumes a linear relationship between the funding allocated to conservation of a taxon and the increased survival probability of that taxon. This relationship is briefly investigated and one variation is suggested that can also be solved using a greedy algorithm.
Algorithm of probabilistic assessment of fully-mechanized longwall downtime
NASA Astrophysics Data System (ADS)
Domrachev, A. N.; Rib, S. V.; Govorukhin, Yu M.; Krivopalov, V. G.
2017-09-01
The problem of increasing the load on a long fully-mechanized longwall has several aspects, one of which is the improvement of efficiency in using available stoping equipment due to the increase in coefficient of the machine operating time of a shearer and other mining machines that form an integral part of the longwall set of equipment. The task of predicting the reliability indicators of stoping equipment is solved by the statistical evaluation of parameters of downtime exponential distribution and failure recovery. It is more difficult to solve the problems of downtime accounting in case of accidents in the face workings and, despite the statistical data on accidents in mine workings, no solution has been found to date. The authors have proposed a variant of probability assessment of workings caving using Poisson distribution and the duration of their restoration using normal distribution. The above results confirm the possibility of implementing the approach proposed by the authors.
An Extension of Holographic Moiré to Micromechanics
NASA Astrophysics Data System (ADS)
Sciammarella, C. A.; Sciammarella, F. M.
The electronic Holographic Moiré is an ideal tool for micromechanics studies. It does not require a modification of the surface by the introduction of a reference grating. This is of particular advantage when dealing with materials such as solid propellant grains whose chemical nature and surface finish makes the application of a reference grating very difficult. Traditional electronic Holographic Moiré presents some difficult problems when large magnifications are needed and large rigid body motion takes place. This paper presents developments that solves these problems and extends the application of the technique to micromechanics.
{lambda} elements for singular problems in CFD: Viscoelastic fluids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, K.K.; Surana, K.S.
1996-10-01
This paper presents two dimensional {lambda} element formulation for viscoelastic fluid flow containing point singularities in the flow field. The flow of viscoelastic fluid even without singularities are a difficult class of problems for increasing Deborah number or Weissenburg number due to increased dominance of convective terms and thus increased hyperbolicity. In the present work the equations of fluid motion and the constitutive laws are recast in the form of a first order system of coupled equations with the use of auxiliary variables. The velocity, pressure and stresses are interpolated using equal order C{sup 0} {lambda} element approximations. The Leastmore » Squares Finite Element Method (LSFEM) is used to construct the integral form (error functional I) corresponding to these equations. The error functional is constructed by taking the integrated sum of the squares of the errors or residuals (over the whole discretization) resulting when the element approximation is substituted into these equations. The conditions resulting from the minimization of the error functional are satisfied by using Newton`s method with line search. LSFEM has much superior performance when dealing with non-linear and convection dominated problems.« less
Job and life satisfaction of nonstandard workers in South Korea.
Lee, Bokim
2013-08-01
Since the South Korean financial crisis of the late 1990s, the number of nonstandard workers in South Korea has increased rapidly. With such a drastic change, it has been difficult to establish national welfare systems (e.g., accident insurance or support for families with dependent children) for nonstandard workers and identify critical aspects of their health. To evaluate job and life satisfaction among nonstandard workers, this study used a representative sample of South Koreans. Using data from the 2008 Korean Labor and Income Panel Study, the sample size totaled 4,340 observations, of which 1,344 (31.0%) involved nonstandard workers. Significant differences in job and life satisfaction between nonstandard workers and standard workers were found. The results also indicate discrimination in the welfare and fringe benefit systems in South Korea. Occupational health nurses must address the physical and psychological health issues, personal problems, and everyday life concerns of nonstandard workers. Given that the employment status of nonstandard workers in companies is generally unstable, it is difficult for these workers to report poor working conditions to employers or other authorities. Accordingly, occupational health nurses should advocate for nonstandard workers by notifying employers of the many problems they face. Copyright 2013, SLACK Incorporated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berkun, Mehmet; Aras, Egemen; Nemlioglu, Semih
The increasing amount of solid waste arising from municipalities and other sources and its consequent disposal has been one of the major environmental problems in Turkey. Istanbul is a metropolitan city with a current population of around 14 million, and produces about 9000 ton of solid waste every day. The waste composition for Istanbul has changed markedly from 1981 to 1996 with large decreases in waste density, much of which is related to decreased amounts of ash collected in winter. In recent years, the Istanbul region has implemented a new solid waste management system with transfer stations, sanitary landfills, andmore » methane recovery, which has led to major improvements. In the Black Sea region of Turkey, most of the municipal and industrial solid wastes, mixed with hospital and hazardous wastes, are dumped on the nearest lowlands and river valleys or into the sea. The impact of riverside and seashore dumping of solid wastes adds significantly to problems arising from sewage and industry on the Black Sea coast. Appropriate integrated solid waste management systems are needed here as well; however, they have been more difficult to implement than in Istanbul because of more difficult topography, weaker administrative structures, and the lower incomes of the inhabitants.« less
Auditory Processing Disorder (For Parents)
... or other speech-language difficulties? Are verbal (word) math problems difficult for your child? Is your child ... inferences from conversations, understanding riddles, or comprehending verbal math problems — require heightened auditory processing and language levels. ...
Metacognition: Student Reflections on Problem Solving
ERIC Educational Resources Information Center
Wismath, Shelly; Orr, Doug; Good, Brandon
2014-01-01
Twenty-first century teaching and learning focus on the fundamental skills of critical thinking and problem solving, creativity and innovation, and collaboration and communication. Metacognition is a crucial aspect of both problem solving and critical thinking, but it is often difficult to get students to engage in authentic metacognitive…
Beyond Utility Targeting: Toward Axiological Air Operations
2000-01-01
encounter the leader- sociopath , bereft of values, quite willing to live underground in hiding and in- sensitive to the absence of human comforts...that is a mere one thousand value-analysis problems to begin solving. A more difficult problem to solve is the problem of the leader- sociopath
Methods for Multiplex Template Sampling in Digital PCR Assays
Petriv, Oleh I.; Heyries, Kevin A.; VanInsberghe, Michael; Walker, David; Hansen, Carl L.
2014-01-01
The efficient use of digital PCR (dPCR) for precision copy number analysis requires high concentrations of target molecules that may be difficult or impossible to obtain from clinical samples. To solve this problem we present a strategy, called Multiplex Template Sampling (MTS), that effectively increases template concentrations by detecting multiple regions of fragmented target molecules. Three alternative assay approaches are presented for implementing MTS analysis of chromosome 21, providing a 10-fold concentration enhancement while preserving assay precision. PMID:24854517
Methods for multiplex template sampling in digital PCR assays.
Petriv, Oleh I; Heyries, Kevin A; VanInsberghe, Michael; Walker, David; Hansen, Carl L
2014-01-01
The efficient use of digital PCR (dPCR) for precision copy number analysis requires high concentrations of target molecules that may be difficult or impossible to obtain from clinical samples. To solve this problem we present a strategy, called Multiplex Template Sampling (MTS), that effectively increases template concentrations by detecting multiple regions of fragmented target molecules. Three alternative assay approaches are presented for implementing MTS analysis of chromosome 21, providing a 10-fold concentration enhancement while preserving assay precision.
Fabrication Of Metal Chloride Cathodes By Sintering
NASA Technical Reports Server (NTRS)
Bugga, Ratnakumar V.; Di Stefano, Salvador; Bankston, C. Perry
1992-01-01
Transition-metal chloride cathodes for use in high-temperature rechargeable sodium batteries prepared by sintering transition-metal powders mixed with sodium chloride. Need for difficult and dangerous chlorination process eliminated. Proportions of transition metal and sodium chloride in mixture adjusted to suit specific requirements. Cathodes integral to sodium/metal-chloride batteries, which have advantages over sodium/sulfur batteries including energy densities, increased safety, reduced material and thermal-management problems, and ease of operation and assembly. Being evaluated for supplying electrical power during peak demand and electric vehicles.
Optimization of 31P magnetic resonance spectroscopy in vivo
NASA Astrophysics Data System (ADS)
Manzhurtsev, A. V.; Akhadov, T. A.; Semenova, N. A.
2018-01-01
The main problem of magnetic resonance spectroscopy on phosphorus nuclei (31P MRS) is low signal-to-noise ratio (SNR) of spectra acquired on clinical (3T) scanners. This makes quantitative processing of spectra difficult. The optimization of method on a single-voxel model reported in current work implicates an impact of the spin-lattice (T1) relaxation on SNR, and also evaluates the effectiveness of Image Selected InVivo Spectroscopy (ISIS) pulse sequence modification for the increase of SNR.
Minimal Increase Network Coding for Dynamic Networks.
Zhang, Guoyin; Fan, Xu; Wu, Yanxia
2016-01-01
Because of the mobility, computing power and changeable topology of dynamic networks, it is difficult for random linear network coding (RLNC) in static networks to satisfy the requirements of dynamic networks. To alleviate this problem, a minimal increase network coding (MINC) algorithm is proposed. By identifying the nonzero elements of an encoding vector, it selects blocks to be encoded on the basis of relationship between the nonzero elements that the controls changes in the degrees of the blocks; then, the encoding time is shortened in a dynamic network. The results of simulations show that, compared with existing encoding algorithms, the MINC algorithm provides reduced computational complexity of encoding and an increased probability of delivery.
Minimal Increase Network Coding for Dynamic Networks
Wu, Yanxia
2016-01-01
Because of the mobility, computing power and changeable topology of dynamic networks, it is difficult for random linear network coding (RLNC) in static networks to satisfy the requirements of dynamic networks. To alleviate this problem, a minimal increase network coding (MINC) algorithm is proposed. By identifying the nonzero elements of an encoding vector, it selects blocks to be encoded on the basis of relationship between the nonzero elements that the controls changes in the degrees of the blocks; then, the encoding time is shortened in a dynamic network. The results of simulations show that, compared with existing encoding algorithms, the MINC algorithm provides reduced computational complexity of encoding and an increased probability of delivery. PMID:26867211
Kapornai, Krisztina; Gentzler, Amy L; Tepper, Ping; Kiss, Eniko; Mayer, László; Tamás, Zsuzsanna; Kovacs, Maria; Vetró, Agnes
2007-06-01
We investigate the relations of early atypical characteristics (perinatal problems, developmental delay, and difficult temperament) and onset-age (as well as severity of) first major depressive disorder (MDD) and first internalizing disorder in a clinical sample of depressed children in Hungary. Participants were 371 children (ages 7-14) with MDD, and their biological mothers, recruited through multiple clinical sites. Diagnoses (via DSM-IV criteria) and onset dates of disorders were finalized "best estimate" psychiatrists, and based on multiple information sources. Mothers provided developmental data in a structured interview. Difficult temperament predicted earlier onset of MDD and first internalizing disorder, but its effect was ameliorated if the family was intact during early childhood. Further, the importance of difficult temperament decreased as a function of time. Perinatal problems and developmental delay did not impact onset ages of disorders, and none of the early childhood characteristics associated with MDD episode severity. Children with MDD may have added disadvantage of earlier onset if they had a difficult temperament in infancy. Because early temperament mirrors physiological reactivity and regulatory capacity, it can affect various areas of functioning related to psychopathology. Early caregiver stability may attenuate some adverse effects of difficult infant temperament.
Physician crimes and criminals. The historical and forensic aspects.
Eckert, W G
1982-09-01
The physician, like any other human being, is subject to emotional problems, greed, jealousy, and instability of an individual under stress as well as mental disease which may all bring out improper behavior or criminal activity. Over the last two centuries, there have been instances where physicians have committed deliberate acts of murder on wives, relatives, patients, and others. Their motivation has ranged from ridding themselves of a nagging wife or for insurance and inheritance gains to insane acts. The methods used have usually been associated with poisons and drugs, of which the physician may have great familiarity. The frequency of physician-involved murders seems to have increased in the past two decades with several sensational cases being the topics of media coverage and further review in books and visual media, including television and the movies. The investigation of these cases may be very difficult, especially when a drug may be given to a victim which could cause severe problems after small amounts are given. The detection of death as being a murder may be the first problem faced, the demonstration of the fatal agent in the body in the next problem, and probably the most difficult is finding a suspect with the medication in his or her possession or paraphenalia for injecting such as a syringe and needle. The stealth and cunning of the murderer may further complicate the picture for the investigator as well as the reputation of the physician in the community, which is often above reproach so that the public has to be convinced of the actual involvement of the suspect.
Using Predictor-Corrector Methods in Numerical Solutions to Mathematical Problems of Motion
ERIC Educational Resources Information Center
Lewis, Jerome
2005-01-01
In this paper, the author looks at some classic problems in mathematics that involve motion in the plane. Many case problems like these are difficult and beyond the mathematical skills of most undergraduates, but computational approaches often require less insight into the subtleties of the problems and can be used to obtain reliable solutions.…
Monitoring Affect States during Effortful Problem Solving Activities
ERIC Educational Resources Information Center
D'Mello, Sidney K.; Lehman, Blair; Person, Natalie
2010-01-01
We explored the affective states that students experienced during effortful problem solving activities. We conducted a study where 41 students solved difficult analytical reasoning problems from the Law School Admission Test. Students viewed videos of their faces and screen captures and judged their emotions from a set of 14 states (basic…
Home Economics Reading Skills: Problems and Selected References.
ERIC Educational Resources Information Center
Cranney, A. Garr; And Others
Home economics presents at least eight problems to secondary school reading teachers. These problems include poor readers, difficult reading material, lack of reading materials, teachers' lack of training in reading instruction, scarce information about home economics for reading teachers, diversity of the home economics field (requiring a wide…
A Fiducial Approach to Extremes and Multiple Comparisons
ERIC Educational Resources Information Center
Wandler, Damian V.
2010-01-01
Generalized fiducial inference is a powerful tool for many difficult problems. Based on an extension of R. A. Fisher's work, we used generalized fiducial inference for two extreme value problems and a multiple comparison procedure. The first extreme value problem is dealing with the generalized Pareto distribution. The generalized Pareto…
Students' and Teachers' Conceptual Metaphors for Mathematical Problem Solving
ERIC Educational Resources Information Center
Yee, Sean P.
2017-01-01
Metaphors are regularly used by mathematics teachers to relate difficult or complex concepts in classrooms. A complex topic of concern in mathematics education, and most STEM-based education classes, is problem solving. This study identified how students and teachers contextualize mathematical problem solving through their choice of metaphors.…
Cognitive Development, Genetics Problem Solving, and Genetics Instruction: A Critical Review.
ERIC Educational Resources Information Center
Smith, Mike U.; Sims, O. Suthern, Jr.
1992-01-01
Review of literature concerning problem solving in genetics and Piagetian stage theory. Authors conclude the research suggests that formal-operational thought is not strictly required for the solution of the majority of classical genetics problems; however, some genetic concepts are difficult for concrete operational students to understand.…
ERIC Educational Resources Information Center
Danielsen, Reidar
Skilled labor has always been difficult to recruit, and in a tight labor market unskilled, low-paying jobs with low status are also difficult to fill. Recruitment from outside seems necessary to satisfy demands, but migration creates at least as many problems as it solves. The consumption of theoretical training through the university level (a…
Professional Support for Families in Difficult Life Situations
ERIC Educational Resources Information Center
Zakirova, Venera G.; Gaysina, Guzel I.; Raykova, Elena
2016-01-01
Relevance of the problem stated in the article is determined by the presence of a significant number of families in difficult life situations who need in professional support and socio-psychological assistance. The article aims to substantiate the effectiveness of the structural-functional model of professional supporting for families in difficult…
ERIC Educational Resources Information Center
Worth-Baker, Marcia
2000-01-01
Describes one seventh grade teacher's experiences with a student from a problem home who was known for his difficult behavior, noting the student's deep interest in the Trojan War and its circumstances, describing his death at age 16, and concluding that it is important to notice and cherish all students, even the difficult ones. (SM)
Formal methods technology transfer: Some lessons learned
NASA Technical Reports Server (NTRS)
Hamilton, David
1992-01-01
IBM has a long history in the application of formal methods to software development and verification. There have been many successes in the development of methods, tools and training to support formal methods. And formal methods have been very successful on several projects. However, the use of formal methods has not been as widespread as hoped. This presentation summarizes several approaches that have been taken to encourage more widespread use of formal methods, and discusses the results so far. The basic problem is one of technology transfer, which is a very difficult problem. It is even more difficult for formal methods. General problems of technology transfer, especially the transfer of formal methods technology, are also discussed. Finally, some prospects for the future are mentioned.
NASA Astrophysics Data System (ADS)
Gen, Mitsuo; Lin, Lin
Many combinatorial optimization problems from industrial engineering and operations research in real-world are very complex in nature and quite hard to solve them by conventional techniques. Since the 1960s, there has been an increasing interest in imitating living beings to solve such kinds of hard combinatorial optimization problems. Simulating the natural evolutionary process of human beings results in stochastic optimization techniques called evolutionary algorithms (EAs), which can often outperform conventional optimization methods when applied to difficult real-world problems. In this survey paper, we provide a comprehensive survey of the current state-of-the-art in the use of EA in manufacturing and logistics systems. In order to demonstrate the EAs which are powerful and broadly applicable stochastic search and optimization techniques, we deal with the following engineering design problems: transportation planning models, layout design models and two-stage logistics models in logistics systems; job-shop scheduling, resource constrained project scheduling in manufacturing system.
Treatment preparation in the context of system coordination serves inmates well.
Windell, Phillip A; Barron, Nancy
2002-01-01
A large percentage of jail inmates suffer from substance abuse problems; however, providing treatment in jail is difficult. Multnomah County's In Jail Intervention Program (IJIP) demonstrated an effective alternative. Finigan, Barron, and Carey (In press) and Barron and Finigan (1999) demonstrated that inmates with substance use problems, especially women, participating in IJIP experienced fewer rearrests and reincarcerations. To address the question of what led to these outcomes, quantitative data were abstracted from program, jail, and state administrative databases and were supplemented by face-to-face interviews with key informants, including program participants and former participants. In addition to their substance abuse problems, IJIP participants were chronic offenders who were more likely to be diagnosed with mental health problems. Results suggest that treatment preparation together with coordination of jail release and entry to treatment increased numbers enrolling in treatment and helped former inmates engage in treatment more quickly. Quantitative data suggest that the longer inmates stayed in IJIP, the more likely was completion of community treatment.
NASA Astrophysics Data System (ADS)
Chen, Miawjane; Yan, Shangyao; Wang, Sin-Siang; Liu, Chiu-Lan
2015-02-01
An effective project schedule is essential for enterprises to increase their efficiency of project execution, to maximize profit, and to minimize wastage of resources. Heuristic algorithms have been developed to efficiently solve the complicated multi-mode resource-constrained project scheduling problem with discounted cash flows (MRCPSPDCF) that characterize real problems. However, the solutions obtained in past studies have been approximate and are difficult to evaluate in terms of optimality. In this study, a generalized network flow model, embedded in a time-precedence network, is proposed to formulate the MRCPSPDCF with the payment at activity completion times. Mathematically, the model is formulated as an integer network flow problem with side constraints, which can be efficiently solved for optimality, using existing mathematical programming software. To evaluate the model performance, numerical tests are performed. The test results indicate that the model could be a useful planning tool for project scheduling in the real world.
The Golden bypass landslide, Golden, Colorado
Highland, L.M.; Brown, W. M.
1993-01-01
Slope instability along a new highway bypass in Golden, Colorado, became a major concern in 1993. Rains and snowmelt accelerated movement of a landslide that had begun to develop before the bypass was opened to traffic in July of 1991. The downslope movement of earth materials increased significantly in 1993. During the first few months of the year, the landslide pushed onto the west shoulder of the road and crumpled the pavement beneath the south-bound lane. As we prepare this article (September, 1993), the slide continues to encroach onto the highway, posing a persistent problem despite repeated efforts to slow or stop its movement. As this article will show, permanent solutions to landslide problems of this kind are difficult to obtain.
Lean on Wii: physical rehabilitation with virtual reality Wii peripherals.
Anderson, Fraser; Annett, Michelle; Bischof, Walter F
2010-01-01
In recent years, a growing number of occupational therapists have integrated video game technologies, such as the Nintendo Wii, into rehabilitation programs. 'Wiihabilitation', or the use of the Wii in rehabilitation, has been successful in increasing patients' motivation and encouraging full body movement. The non-rehabilitative focus of Wii applications, however, presents a number of problems: games are too difficult for patients, they mainly target upper-body gross motor functions, and they lack support for task customization, grading, and quantitative measurements. To overcome these problems, we have designed a low-cost, virtual-reality based system. Our system, Virtual Wiihab, records performance and behavioral measurements, allows for activity customization, and uses auditory, visual, and haptic elements to provide extrinsic feedback and motivation to patients.
A Distributed Approach to System-Level Prognostics
NASA Technical Reports Server (NTRS)
Daigle, Matthew J.; Bregon, Anibal; Roychoudhury, Indranil
2012-01-01
Prognostics, which deals with predicting remaining useful life of components, subsystems, and systems, is a key technology for systems health management that leads to improved safety and reliability with reduced costs. The prognostics problem is often approached from a component-centric view. However, in most cases, it is not specifically component lifetimes that are important, but, rather, the lifetimes of the systems in which these components reside. The system-level prognostics problem can be quite difficult due to the increased scale and scope of the prognostics problem and the relative Jack of scalability and efficiency of typical prognostics approaches. In order to address these is ues, we develop a distributed solution to the system-level prognostics problem, based on the concept of structural model decomposition. The system model is decomposed into independent submodels. Independent local prognostics subproblems are then formed based on these local submodels, resul ting in a scalable, efficient, and flexible distributed approach to the system-level prognostics problem. We provide a formulation of the system-level prognostics problem and demonstrate the approach on a four-wheeled rover simulation testbed. The results show that the system-level prognostics problem can be accurately and efficiently solved in a distributed fashion.
Problems of modern urban drainage in developing countries.
Silveira, A L L
2002-01-01
Socio-economic factors in developing countries make it more difficult to solve problems of urban drainage than in countries that are more advanced. Factors inhibiting the adoption of modern solutions include: (1) in matters of urban drainage, 19th-century sanitary philosophy still dominates; (2) both legal and clandestine land settlement limits the space that modern solutions require; (3) contamination of storm runoff by foul sewage, sediment and garbage prevents adoption of developed-country practices; (4) climatic and socio-economic factors favour the growth of epidemics where runoff is retained for flood-avoidance and to increase infiltration; (5) lack of a technological basis for adequate drainage management and design; (6) lack of the interaction between community and city administration that is needed to obtain modern solutions to urban drainage problems. Awareness of these difficulties is fundamental to the search for modern and viable solutions appropriate for developing countries.
Virtual morality: emotion and action in a simulated three-dimensional "trolley problem".
Navarrete, C David; McDonald, Melissa M; Mott, Michael L; Asher, Benjamin
2012-04-01
Experimentally investigating the relationship between moral judgment and action is difficult when the action of interest entails harming others. We adopt a new approach to this problem by placing subjects in an immersive, virtual reality environment that simulates the classic "trolley problem." In this moral dilemma, the majority of research participants behaved as "moral utilitarians," either (a) acting to cause the death of one individual in order to save the lives of five others, or (b) abstaining from action, when that action would have caused five deaths versus one. Confirming the emotional distinction between moral actions and omissions, autonomic arousal was greater when the utilitarian outcome required action, and increased arousal was associated with a decreased likelihood of utilitarian-biased behavior. This pattern of results held across individuals of different gender, age, and race. (PsycINFO Database Record (c) 2012 APA, all rights reserved).
ERIC Educational Resources Information Center
Cooper, Melanie M.; Cox, Charles T., Jr.; Nammouz, Minory; Case, Edward; Stevens, Ronald
2008-01-01
Improving students' problem-solving skills is a major goal for most science educators. While a large body of research on problem solving exists, assessment of meaningful problem solving is very difficult, particularly for courses with large numbers of students in which one-on-one interactions are not feasible. We have used a suite of software…
ERIC Educational Resources Information Center
Danek, Amory H.; Wiley, Jennifer; Öllinger, Michael
2016-01-01
Insightful problem solving is a vital part of human thinking, yet very difficult to grasp. Traditionally, insight has been investigated by using a set of established "insight tasks," assuming that insight has taken place if these problems are solved. Instead of assuming that insight takes place during every solution of the 9 Dot, 8 Coin,…
Solving Constraint Satisfaction Problems with Networks of Spiking Neurons
Jonke, Zeno; Habenschuss, Stefan; Maass, Wolfgang
2016-01-01
Network of neurons in the brain apply—unlike processors in our current generation of computer hardware—an event-based processing strategy, where short pulses (spikes) are emitted sparsely by neurons to signal the occurrence of an event at a particular point in time. Such spike-based computations promise to be substantially more power-efficient than traditional clocked processing schemes. However, it turns out to be surprisingly difficult to design networks of spiking neurons that can solve difficult computational problems on the level of single spikes, rather than rates of spikes. We present here a new method for designing networks of spiking neurons via an energy function. Furthermore, we show how the energy function of a network of stochastically firing neurons can be shaped in a transparent manner by composing the networks of simple stereotypical network motifs. We show that this design approach enables networks of spiking neurons to produce approximate solutions to difficult (NP-hard) constraint satisfaction problems from the domains of planning/optimization and verification/logical inference. The resulting networks employ noise as a computational resource. Nevertheless, the timing of spikes plays an essential role in their computations. Furthermore, networks of spiking neurons carry out for the Traveling Salesman Problem a more efficient stochastic search for good solutions compared with stochastic artificial neural networks (Boltzmann machines) and Gibbs sampling. PMID:27065785
Fecal contamination of waters used for recreation, drinking water, and aquaculture is an environmental problem and poses significant human health risks. The problem is often difficult to correct because the source of the contamination cannot be determined with certainty. Run-of...
Evolving neural networks for strategic decision-making problems.
Kohl, Nate; Miikkulainen, Risto
2009-04-01
Evolution of neural networks, or neuroevolution, has been a successful approach to many low-level control problems such as pole balancing, vehicle control, and collision warning. However, certain types of problems-such as those involving strategic decision-making-have remained difficult for neuroevolution to solve. This paper evaluates the hypothesis that such problems are difficult because they are fractured: The correct action varies discontinuously as the agent moves from state to state. A method for measuring fracture using the concept of function variation is proposed and, based on this concept, two methods for dealing with fracture are examined: neurons with local receptive fields, and refinement based on a cascaded network architecture. Experiments in several benchmark domains are performed to evaluate how different levels of fracture affect the performance of neuroevolution methods, demonstrating that these two modifications improve performance significantly. These results form a promising starting point for expanding neuroevolution to strategic tasks.
NASA Astrophysics Data System (ADS)
Nakanishi, Mayumi; Hoshino, Satoshi; Hashimoto, Shizuka; Kuki, Yasuaki
The problems of Marginal Hamlets are getting worse, in which more than half of the population is over 65 and community-based life is difficult. To contribute to effective policy making, we conducted a questionnaire survey to members of the National Liaison Council of ‘Suigen no Sato’ constituted to share information about problems and effective counter measures for marginal hamlets. Our study clarified that first, most of respondents had common problems such as lack of job-opportunities and animal damage on farm, and second, though most of respondents recognized the effectiveness of selecting target communities in policy implementations, it is difficult for municipal governments to establish such ordinance provided that councilors and those who were not living in areas of policy target wouldn't agree with it. Finally, we pointed out the roles of national and prefectural governments to help municipal governments effectively cope with such entangled situations.
Rosvall, Per-Åke; Nilsson, Stefan
2016-08-30
There has been an increase of reports describing mental health problems in adolescents, especially girls. School nurses play an important role in supporting young people with health problems. Few studies have considered how the nurses' gender norms may influence their discussions. To investigate this issue, semi-structured interviews focusing on school nurses' work with students who have mental health problems were conducted. Transcripts of interviews with Swedish school nurses (n = 15) from the Help overcoming pain early project (HOPE) were analysed using theories on gender as a theoretical framework and then organised into themes related to the school nurses' provision of contact and intervention. The interviewees were all women, aged between 42-63 years, who had worked as nurses for 13-45 years, and as school nurses for 2-28 years. Five worked in upper secondary schools (for students aged 16-19) and 10 in secondary schools (for students aged 12-16). The results show that school nurses more commonly associated mental health problems with girls. When the school nurses discussed students that were difficult to reach, boys in particular were mentioned. However, very few nurses mentioned specific intervention to address students' mental health problems, and all of the mentioned interventions were focused on girls. Some of the school nurses reported that it was more difficult to initiate a health dialogue with boys, yet none of the nurses had organized interventions for the boys. We conclude that generalisations can sometimes be analytically helpful, facilitating, for instance, the identification of problems in school nurses' work methods and interventions. However, the most important conclusion from our research, which applied a design that is not commonly used, is that more varied approaches, as well as a greater awareness of potential gender stereotype pitfalls, are necessary to meet the needs of diverse student groups.
A Programming Framework for Scientific Applications on CPU-GPU Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Owens, John
2013-03-24
At a high level, my research interests center around designing, programming, and evaluating computer systems that use new approaches to solve interesting problems. The rapid change of technology allows a variety of different architectural approaches to computationally difficult problems, and a constantly shifting set of constraints and trends makes the solutions to these problems both challenging and interesting. One of the most important recent trends in computing has been a move to commodity parallel architectures. This sea change is motivated by the industry’s inability to continue to profitably increase performance on a single processor and instead to move to multiplemore » parallel processors. In the period of review, my most significant work has been leading a research group looking at the use of the graphics processing unit (GPU) as a general-purpose processor. GPUs can potentially deliver superior performance on a broad range of problems than their CPU counterparts, but effectively mapping complex applications to a parallel programming model with an emerging programming environment is a significant and important research problem.« less
Whalen, Madeleine; Maliszewski, Barbara; Sheinfeld, Rebecca; Gardner, Heather; Baptiste, Diana
2018-04-25
Difficult venous access is a common problem in health care-especially in the emergency setting-that relies on quick diagnostics to differentiate patient acuities and administer critical medications. The creation of a dedicated team to address difficult venous access (DVA) is a possible solution to the problems of delayed venous access, yet no studies have been published on implementing such a team in the emergency department. This was a quasi-experimental study in an urban emergency department. Researchers performed chart audits of staff-identified patients with DVA to gather baseline data. A DVA team was subsequently implemented 16 hours a day, 7 days a week. Data were recorded on patients referred to the team and included time, number of IV attempts, and patient characteristics. Baseline data were collected on 53 patients, and postintervention data included 135 patients. The implementation of a DVA team decreased the mean lab order-to-lab completion time by 115 minutes (P < 0.0001). Decreases in the number of attempts were not statistically significant. Patients requiring increased numbers of IV attempts also had many common characteristics including history of multiple attempts, poor skin quality, and IV drug use. The use of a dedicated team for DVA reduces the lag time from physician orders to actionable diagnostics or administration of medication. A dedicated DVA technician is a concrete solution to threats of patient safety, as well as ED crowding, and has the potential to affect both patient- and department-level care. Copyright © 2018 Elsevier Inc. All rights reserved.
Fast and Efficient Discrimination of Traveling Salesperson Problem Stimulus Difficulty
ERIC Educational Resources Information Center
Dry, Matthew J.; Fontaine, Elizabeth L.
2014-01-01
The Traveling Salesperson Problem (TSP) is a computationally difficult combinatorial optimization problem. In spite of its relative difficulty, human solvers are able to generate close-to-optimal solutions in a close-to-linear time frame, and it has been suggested that this is due to the visual system's inherent sensitivity to certain geometric…
The Problem Solving Studio: An Apprenticeship Environment for Aspiring Engineers
ERIC Educational Resources Information Center
Le Doux, Joseph M.; Waller, Alisha A.
2016-01-01
This paper describes the problem-solving studio (PSS) learning environment. PSS was designed to teach students how to solve difficult analytical engineering problems without resorting to rote memorization of algorithms, while at the same time developing their deep conceptual understanding of the course topics. There are several key features of…
ERIC Educational Resources Information Center
Walker, Decker F.
This paper addresses the reasons that it is difficult to find good educational software and proposes measures for coping with this problem. The fundamental problem is a shortange of educational software that can be used as a major part of the teaching of academic subjects in elementary and secondary schools--a shortage that is both the effect and…
Why Inquiry Is Inherently Difficult...and Some Ways to Make It Easier
ERIC Educational Resources Information Center
Meyer, Daniel Z.; Avery, Leanne M.
2010-01-01
In this article, the authors offer a framework that identifies two critical problems in designing inquiry-based instruction and suggests three models for developing instruction that overcomes those problems. The Protocol Model overcomes the Getting on Board Problem by providing students an initial experience through clearly delineated steps with a…
How to Arrive at Good Research Questions?
ERIC Educational Resources Information Center
Gafoor, K. Abdul
2008-01-01
Identifying an area of research a topic, deciding on a problem, and formulating it in to a researchable question are very difficult stages in the whole research process at least for beginners. Few books on research methodology elaborates the various process involved in problem selection and clarification. Viewing research and problem selection as…
Integrating Worked Examples into Problem Posing in a Web-Based Learning Environment
ERIC Educational Resources Information Center
Hsiao, Ju-Yuan; Hung, Chun-Ling; Lan, Yu-Feng; Jeng, Yoau-Chau
2013-01-01
Most students always lack of experience and perceive difficult regarding problem posing. The study hypothesized that worked examples may have benefits for supporting students' problem posing activities. A quasi-experiment was conducted in the context of a business mathematics course for examining the effects of integrating worked examples into…
The study of production performance of water heater manufacturing by using simulation method
NASA Astrophysics Data System (ADS)
Iqbal, M.; Bamatraf, OAA; Tadjuddin, M.
2018-02-01
In industrial companies, as demand increases, decision-making to increase production becomes difficult due to the complexity of the model systems. Companies are trying to find the optimum methods to tackle such problems so that resources are utilized and production is increased. One line system of a manufacturing company in Malaysia was considered in this research. The Company produces several types of water heater and each type went into many processes, which was divided into twenty six sections. Each section has several operations. The main type of the product was 10G water heater which is produced most compare to other types, hence it was taken under consideration to be studied in this research. It was difficult to find the critical section that could improve the productions of the company. This research paper employed Delmia Quest software, Distribution Analyser software and Design of Experiment (DOE software) to simulate one model system taken from the company to be studied and to find the critical section that will improve the production system. As a result, assembly of inner and outer tank section were found to be the bottleneck section. Adding one section to the bottleneck increases the production rate by four products a day. The buffer size is determined by the experiment was six items.
ERIC Educational Resources Information Center
Kerr, Deirdre
2014-01-01
Educational video games provide an opportunity for students to interact with and explore complex representations of academic content and allow for the examination of problem-solving strategies and mistakes that can be difficult to capture in more traditional environments. However, data from such games are notoriously difficult to analyze. This…
Overcoming Misconceptions in Neurophysiology Learning: An Approach Using Color-Coded Animations
ERIC Educational Resources Information Center
Guy, Richard
2012-01-01
Anyone who has taught neurophysiology would be aware of recurring concepts that students find difficult to understand. However, a greater problem is the development of misconceptions that may be difficult to change. For example, one common misconception is that action potentials pass directly across chemical synapses. Difficulties may be…
ERIC Educational Resources Information Center
Auduc, Jean-Louis
This book outlines challenges involved in ensuring that teacher training becomes the gateway to implementation of appropriate strategies for students to achieve and for managing the problems of authority, discipline, and aggressive behavior. The six chapters examine: (1) "Teaching in Schools or Classes Considered Difficult: A Contemporary…
Mimicking cataract-induced visual dysfunction by means of protein denaturation in egg albumen
NASA Astrophysics Data System (ADS)
Mandracchia, B.; Finizio, A.; Ferraro, P.
2016-03-01
As the world's population ages, cataract-induced visual dysfunction and blindness is on the increase. This is a significant global problem. The most common symptoms of cataracts are glared and blurred vision. Usually, people with cataract have trouble seeing and reading at distance or in low light and also their color perception is altered. Furthermore, cataract is a sneaky disease as it is usually a very slow but progressive process, which creates adaptation so that patients find it difficult to recognize. All this can be very difficult to explain, so we built and tested an optical device to help doctors giving comprehensive answers to the patients' symptoms. This device allows visualizing how cataract impairs vision mimicking the optical degradation of the crystalline related cataracts. This can be a valuable optical tool for medical education as well as to provide a method to illustrate the patients how cataract progression process will affect their vision.
Dietary enrichment counteracts age-associated cognitive dysfunction in canines.
Milgram, N W; Zicker, S C; Head, E; Muggenburg, B A; Murphey, H; Ikeda-Douglas, C J; Cotman, C W
2002-01-01
Advanced age is accompanied by cognitive decline indicative of central nervous system dysfunction. One possibly critical causal factor is oxidative stress. Accordingly, we studied the effects of dietary antioxidants and age in a canine model of aging that parallels the key features of cognitive decline and neuropathology in humans. Old and young animals were placed on either a standard control food, or a food enriched with a broad spectrum of antioxidants and mitochondrial enzymatic cofactors. After 6 months of treatment, the animals were tested on four increasingly difficult oddity discrimination learning problems. The old animals learned more slowly than the young, making significantly more errors. However, this age-associated decline was reduced in the animals fed the enriched food, particularly on the more difficult tasks. These results indicate that maintenance on foods fortified with complex mixtures of antioxidants can partially counteract the deleterious effects of aging on cognition. Copyright 2002 Elsevier Science Inc.
NASA Astrophysics Data System (ADS)
Jamaludin, A. S.; Hosokawa, A.; Furumoto, T.; Koyano, T.; Hashimoto, Y.
2018-03-01
Cutting process of difficult-to-cut material such as stainless steel, generates immensely excessive heat, which is one of the major causes related to shortening tool life and lower quality of surface finish. It is proven that application of cutting fluid during the cutting process of difficult-to-cut material is able to improve the cutting performance, but excessive application of cutting fluid leads to another problem such as increasing processing cost and environmental hazardous pollution of workplace. In the study, Extreme Cold Mist system is designed and tested along with various Minimum Quantity Lubrication (MQL) systems on turning process of stainless steel AISI 316. In the study, it is obtained that, Extreme Cold Mist system is able to reduce cutting force up to 60N and improve the surface roughness of the machined surface significantly.
Kuo, Chia-Chi; Feng, I-Jung; Lee, Wei-Jing
2017-10-01
Peripheral intravenous access is a common and invasive procedure that is performed in pediatric clinical settings. Children often have difficult intravenous-access problems that may not only increase staff stress but also affect the timeliness of immediate treatments. To determine the efficacy of near-infrared devices in facilitating peripheral intravenous access in children, using a systematic review and meta-analysis. Six databases, namely the Index to Taiwan Periodical Literature System, Airiti Library, CINAHL, Cochrane Library, PubMed/MEDLINE, and ProQuest were searched for related articles that were published between the earliest year available and February 2017. The search was limited to studies on populations of children that used either a randomized controlled trial or controlled clinical trial approach and used the key words "near-infrared devices" AND "peripheral intravenous access." The 12 articles that met these criteria were included in the analysis. The Cochrane Collaboration bias assessment tool was used to assess the methodological quality. In addition, RevMan 5.3.5 software was used to conduct the meta-analysis. The near-infrared devices did not significantly improve the first-attempt success rate, number of attempts, or the procedural time of peripheral intravenous access in children. However, the subgroup analysis of difficult intravenous-access factors revealed a significant improvement in the first-attempt success rate of children with difficult intravenous access scores (OR = 1.83, p = .03). Near-infrared devices may improve the first-attempt success rate in children with difficult intravenous access by allowing healthcare professionals to visualize the peripheral veins. Therefore, we suggest that the difficult intravenous-access score be used as a screening tool to suggest when to apply near-infrared devices to children with difficult peripheral intravenous access in order to maximize efficacy of treatment.
Autonomous Intersection Management
2009-12-01
is irrelevant. Fortunately, researchers are attacking this problem with many techniques. In 2004, Honda introduced an intelligent night vision system...or less a solved problem . The problem itself is not too difficult: there are no pedestrians or cyclists and vehicles travel in the same direction at...organized according to the following subgoals, each of which is a contribution of the thesis. 1. Problem definition First, this thesis contributes a
The resolvent of singular integral equations. [of kernel functions in mixed boundary value problems
NASA Technical Reports Server (NTRS)
Williams, M. H.
1977-01-01
The investigation reported is concerned with the construction of the resolvent for any given kernel function. In problems with ill-behaved inhomogeneous terms as, for instance, in the aerodynamic problem of flow over a flapped airfoil, direct numerical methods become very difficult. A description is presented of a solution method by resolvent which can be employed in such problems.
The molecular matching problem
NASA Technical Reports Server (NTRS)
Kincaid, Rex K.
1993-01-01
Molecular chemistry contains many difficult optimization problems that have begun to attract the attention of optimizers in the Operations Research community. Problems including protein folding, molecular conformation, molecular similarity, and molecular matching have been addressed. Minimum energy conformations for simple molecular structures such as water clusters, Lennard-Jones microclusters, and short polypeptides have dominated the literature to date. However, a variety of interesting problems exist and we focus here on a molecular structure matching (MSM) problem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dubovsky, E.V.; Curtis, J.J.; Luke, R.G.
Impaired function of renal allografts caused by recurrent disease or rejection is often accompanied by hypertension. The etiology of persistent severe hypertension in recipients with good renal function is more difficult to explain. To study this problem, 33 patients with mean arterial pressure (MAP) > 105 mm Hg (at least one year after transplantation) were tested. When compared to a normotensive group, they were found to have increased renal vascular resistance, lower ERPF, and increased renin-angiotensin activity. The effect of Captopril, a converting enzyme inhibitor, was studied to evaluate the role of angiotension. The paper concludes that Captopril test maymore » permit differentiation between native kidney-dependent hypertension (increase in ERPF) and functionally active renal artery stenosis (decline in ERPF) in patients with persistent hypertension and good renal function.« less
Monclus, Enric; Garcés, Antonio; Artés, David; Mabrock, Maged
2008-07-01
For a predicted difficult airway, oral intubation techniques are well established in pediatric anesthesia, but nasotracheal intubation remains a problem. There are many reports concerning this, but the risk of bleeding, added to the lack of cooperation make this procedure difficult and hazardous. We describe a modification of the nasal intubation technique in two stages. First an oral intubation and then exchanging the oral for a nasal tube, in the case of a 13-year-old boy affected by an advanced stage of cherubism. Oral intubation using a laryngeal mask technique has already been reported, but problems appear during the exchange procedure and even more when direct laryngoscopy is impossible. Fiberscopic control of the exchange, and the introduction of a Cook Exchange Catheter into the trachea through the oral tube before withdrawal, permits oxygenation of the patient and acts as a guide for oral tube reintroduction if required.
Multicategory Composite Least Squares Classifiers
Park, Seo Young; Liu, Yufeng; Liu, Dacheng; Scholl, Paul
2010-01-01
Classification is a very useful statistical tool for information extraction. In particular, multicategory classification is commonly seen in various applications. Although binary classification problems are heavily studied, extensions to the multicategory case are much less so. In view of the increased complexity and volume of modern statistical problems, it is desirable to have multicategory classifiers that are able to handle problems with high dimensions and with a large number of classes. Moreover, it is necessary to have sound theoretical properties for the multicategory classifiers. In the literature, there exist several different versions of simultaneous multicategory Support Vector Machines (SVMs). However, the computation of the SVM can be difficult for large scale problems, especially for problems with large number of classes. Furthermore, the SVM cannot produce class probability estimation directly. In this article, we propose a novel efficient multicategory composite least squares classifier (CLS classifier), which utilizes a new composite squared loss function. The proposed CLS classifier has several important merits: efficient computation for problems with large number of classes, asymptotic consistency, ability to handle high dimensional data, and simple conditional class probability estimation. Our simulated and real examples demonstrate competitive performance of the proposed approach. PMID:21218128
Problem based review: a patient with Parkinson's disease.
Arora, A; Fletcher, P
2013-01-01
Parkinson's disease (PD) is a chronic, progressive neurodegenerative disease characterized by bradykinesia, tremor and/ or rigidity, often with gait disturbance and postural instability. In addition to these typical features, patients with PD may experience further problems related to the disease itself or to the medications used to treat it. These comorbid problems include neuropsychiatric conditions (including psychosis, hallucinations, excessive daytime sleepiness, anxiety, depression, fatigue and dementia) as well as problems associated with autonomic nervous system function such as bowel and bladder function. PD can also present in emergency situations with a 'neuroleptic malignant like picture' and acute psychosis. It is not uncommon to see motor fluctuations due to drug interactions and 'withdrawal' symptoms following dose reduction of dopamine agonists. In patients with PD, disturbances of mental state constitute some of the most difficult treatment challenges of advanced disease, often limiting effective treatment of motor symptoms and leading to increased disability and poor quality of life. While some of these symptoms may be alleviated by antiparkinsonian medication, especially if they are 'off-period' related, treatment-related phenomena are usually exacerbated by increasing the number or dosage of antiparkinsonian drugs. Elimination of exacerbating factors and simplification of drug regimens are the first and most important steps in improvement of such symptoms.
Autopilot, Mind Wandering, and the Out of the Loop Performance Problem.
Gouraud, Jonas; Delorme, Arnaud; Berberian, Bruno
2017-01-01
To satisfy the increasing demand for safer critical systems, engineers have integrated higher levels of automation, such as glass cockpits in aircraft, power plants, and driverless cars. These guiding principles relegate the operator to a monitoring role, increasing risks for humans to lack system understanding. The out of the loop performance problem arises when operators suffer from complacency and vigilance decrement; consequently, when automation does not behave as expected, understanding the system or taking back manual control may be difficult. Close to the out of the loop problem, mind wandering points to the propensity of the human mind to think about matters unrelated to the task at hand. This article reviews the literature related to both mind wandering and the out of the loop performance problem as it relates to task automation. We highlight studies showing how these phenomena interact with each other while impacting human performance within highly automated systems. We analyze how this proximity is supported by effects observed in automated environment, such as decoupling, sensory attention, and cognitive comprehension decrease. We also show that this link could be useful for detecting out of the loop situations through mind wandering markers. Finally, we examine the limitations of the current knowledge because many questions remain open to characterize interactions between out of the loop, mind wandering, and automation.
Sidor, Anna; Thiel-Bonney, Consolata; Kunz, Elisabeth; Eickhorst, Andreas; Cierpka, Manfred
2012-07-01
To investigate the relationship between persistent, excessive crying in 5-month-old infants and the pre- and perinatal adversities as well as postpartal mood of their mothers. A sample of 300 mother-child dyads was examined at infants' age of 18.5 weeks. All mothers exhibited psychosocial risks such as poverty, lack of social support, being underage, drug abuse or mental disorders. Excessive crying was assessed by the Wessel's «rule of threes». Pre-, peri- and postnatal problems were measured by self-report questionnaires. Multivariate data analysis revealed an increased risk for social adversities during pregnancy (OR = 17.66) and unwanted pregnancy (OR = 13.77). For the postnatal period persistent crying was associated with a higher rate of maternal postpartum depressive symptoms, maternal stress, dysfunctional mother-child interactions, perception of the infant as being «difficult» as well as bonding problems. The results point to the influence of prenatal stress in mothers and a primarily unwanted pregnancy on infants' persistent crying. An increased need for support is suggested in cases of considerably reduced well-being of the mother or bonding problems. The combined effect of prenatal variables and relationship variables influences the occurrence and perpetuation of early regulation problems.
Multiobjective Optimization Using a Pareto Differential Evolution Approach
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.; Biegel, Bryan A. (Technical Monitor)
2002-01-01
Differential Evolution is a simple, fast, and robust evolutionary algorithm that has proven effective in determining the global optimum for several difficult single-objective optimization problems. In this paper, the Differential Evolution algorithm is extended to multiobjective optimization problems by using a Pareto-based approach. The algorithm performs well when applied to several test optimization problems from the literature.
A hybrid symbolic/finite-element algorithm for solving nonlinear optimal control problems
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.
1991-01-01
The general code described is capable of solving difficult nonlinear optimal control problems by using finite elements and a symbolic manipulator. Quick and accurate solutions are obtained with a minimum for user interaction. Since no user programming is required for most problems, there are tremendous savings to be gained in terms of time and money.
ERIC Educational Resources Information Center
Yates, Jennifer L.
2011-01-01
The purpose of this research study was to explore the process of learning and development of problem solving skills in radiologic technologists. The researcher sought to understand the nature of difficult problems encountered in clinical practice, to identify specific learning practices leading to the development of professional expertise, and to…
ERIC Educational Resources Information Center
Westbrook, Amy F.
2011-01-01
It can be difficult to find adequate strategies when teaching problem solving in a standard based mathematics classroom. The purpose of this study was to improve students' problem solving skills and attitudes through differentiated instruction when working on lengthy performance tasks in cooperative groups. This action research studied for 15 days…
ERIC Educational Resources Information Center
Tawfik, Andrew A.
2017-01-01
Theorists have argued instructional strategies that emphasize ill-structured problem solving are an effective means to support higher order learning skills such as argumentation. However, argumentation is often difficult because novices lack the expertise or experience needed to solve contextualized problems. One way to supplement this lack of…
ERIC Educational Resources Information Center
Vick, Malcolm
2006-01-01
Current reviews of teacher education pay considerable attention to problems associated with the practicum, and often claim to propose major changes in order to improve the quality of new graduates. Many of the problems they address concerning the practicum and its relation to the "theoretical" component of programs are longstanding, and…
ERIC Educational Resources Information Center
DOLBY, J.L.; AND OTHERS
THE STUDY IS CONCERNED WITH THE LINGUISTIC PROBLEM INVOLVED IN TEXT COMPRESSION--EXTRACTING, INDEXING, AND THE AUTOMATIC CREATION OF SPECIAL-PURPOSE CITATION DICTIONARIES. IN SPITE OF EARLY SUCCESS IN USING LARGE-SCALE COMPUTERS TO AUTOMATE CERTAIN HUMAN TASKS, THESE PROBLEMS REMAIN AMONG THE MOST DIFFICULT TO SOLVE. ESSENTIALLY, THE PROBLEM IS TO…
EEG Estimates of Cognitive Workload and Engagement Predict Math Problem Solving Outcomes
ERIC Educational Resources Information Center
Beal, Carole R.; Galan, Federico Cirett
2012-01-01
In the present study, the authors focused on the use of electroencephalography (EEG) data about cognitive workload and sustained attention to predict math problem solving outcomes. EEG data were recorded as students solved a series of easy and difficult math problems. Sequences of attention and cognitive workload estimates derived from the EEG…
The Compound Atwood Machine Problem
ERIC Educational Resources Information Center
Coelho, R. Lopes
2017-01-01
The present paper accounts for progress in physics teaching in the sense that a problem, which has been closed to students for being too difficult, is gained for the high school curriculum. This problem is the compound Atwood machine with three bodies. Its introduction into high school classes is based on a recent study on the weighing of an…
The compound Atwood machine problem
NASA Astrophysics Data System (ADS)
Lopes Coelho, R.
2017-05-01
The present paper accounts for progress in physics teaching in the sense that a problem, which has been closed to students for being too difficult, is gained for the high school curriculum. This problem is the compound Atwood machine with three bodies. Its introduction into high school classes is based on a recent study on the weighing of an Atwood machine.
2010-05-03
this gap might be filled. It will focus on the surface warfare aspect of sea control, though it touches on antiair warfare, mine warfare and...Sea As the flotilla acquired battle power […] the vital, most difficult, and most absorbing problem has become not how to increase the power of a...proving that their performance is absolutely necessary to these operations. Com Fr Amphib TG of the NATO Reaction Force-8 after Exercise Brilliant Midas
The appropriate use of technology (particularly in medical problems of the elderly).
Gilbert, F I
1990-09-01
Technology, particularly "high" technology, with little solid data, is often blamed for much of our increasing cost of health care. Politics and emotions are poor substitutes for accurate information needed for rational solutions. By targeting the desired outcome and studying the process needed to reach the outcome, we can make better decisions. The methods of designing, conducting and funding the studies needed to answer the difficult questions posed by the use of high technology in the elderly are available. Do we have the wisdom to use them?
The Impact of Austerity on Mental Health Service Provision: A UK Perspective.
Cummins, Ian
2018-06-01
This is a discussion paper which examines the impact of austerity policies on the provision of mental health services in the United Kingdom. Austerity is a shorthand for a series of policies introduced by the Conservative and Liberal Democrat Coalition government in the UK from 2010 onwards. In response to the fiscal crisis following the bail out of the banks in 2008, it was argued that significant reductions in public spending were required. The background to these policies is examined before a consideration of their impact on mental health services. These policies had a disproportionate impact on people living in poverty. People with health problems including mental problems are overrepresented in this group. At the same time, welfare and community services are under increasing financial pressures having to respond to increased demand within a context of reduced budgets. There is increasing recognition of the role that social factors and adverse childhood experiences have in the development and trajectory of mental health problems. Mental health social workers, alongside other professionals, seek to explain mental distress by the use of some variant of a biopsychosocial model. The extent of mental health problems as a one of their measures of the impact of inequality. More unequal societies create greater levels of distress. There is a social gradient in the extent of mental health problems-the impact of severe mental illness means that many individuals are unable to work or, if they can return to work, they find it difficult to gain employment because of discrimination. The paper concludes that austerity and associated policies have combined to increase the overall burden of mental distress and marginalisation within the UK.
Action Learning: a new method to increase tractor rollover protective structure (ROPS) adoption.
Biddle, Elyce Anne; Keane, Paul R
2012-01-01
Action Learning is a problem-solving process that is used in various industries to address difficult problems. This project applied Action Learning to a leading problem in agricultural safety. Tractor overturns are the leading cause of fatal injury to farmworkers. This cause of injury is preventable using rollover protective structures (ROPS), protective equipment that functions as a roll bar structure to protect the operator in the event of an overturn. For agricultural tractors manufactured after 1976 and employee operated, Occupational Safety and Health Administration (OSHA) regulation requires employers to equip them with ROPS and seat belts. By the mid-1980s, US tractor manufacturers began adding ROPS on all farm tractors over 20 horsepower sold in the United States (http://www.nasdonline.org/document/113/d001656/rollover-protection-for-farm-tractor-operators.html). However, many older tractors remain in use without ROPS, putting tractor operators at continued risk for traumatic injury and fatality. For many older tractor models ROPS are available for retrofit, but for a variety of reasons, tractor owners have not chosen to retrofit those ROPS. The National Institute for Occupational Safety and Health (NIOSH) attempted various means to ameliorate this occupational safety risk, including the manufacture of a low-cost ROPS for self-assembly. Other approaches address barriers to adoption. An Action Learning approach to increasing adoption of ROPS was followed in Virginia and New York, with mixed results. Virginia took action to increase the manufacturing and adoption of ROPS, but New York saw problems that would be insurmountable. Increased focus on team composition might be needed to establish effective Action Learning teams to address this problem.
Action Learning: A New Method to Increase Tractor Rollover Protective Structure (ROPS) Adoption
Biddle, Elyce Anne; Keane, Paul R.
2016-01-01
Action Learning is a problem-solving process that is used in various industries to address difficult problems. This project applied Action Learning to a leading problem in agricultural safety. Tractor overturns are the leading cause of fatal injury to farmworkers. This cause of injury is preventable using rollover protective structures (ROPS), protective equipment that functions as a roll bar structure to protect the operator in the event of an overturn. For agricultural tractors manufactured after 1976 and employee operated, Occupational Safety and Health Administration (OSHA) regulation requires employers to equip them with ROPS and seat belts. By the mid-1980s, US tractor manufacturers began adding ROPS on all farm tractors over 20 horsepower sold in the United States (http://www.nasdonline.org/document/113/d001656/rollover-protection-for-farm-tractor-operators.html). However, many older tractors remain in use without ROPS, putting tractor operators at continued risk for traumatic injury and fatality. For many older tractor models ROPS are available for retrofit, but for a variety of reasons, tractor owners have not chosen to retrofit those ROPS. The National Institute for Occupational Safety and Health (NIOSH) attempted various means to ameliorate this occupational safety risk, including the manufacture of a low-cost ROPS for self-assembly. Other approaches address barriers to adoption. An Action Learning approach to increasing adoption of ROPS was followed in Virginia and New York, with mixed results. Virginia took action to increase the manufacturing and adoption of ROPS, but New York saw problems that would be insurmountable. Increased focus on team composition might be needed to establish effective Action Learning teams to address this problem. PMID:22994641
ERIC Educational Resources Information Center
Kochanska, Grazyna; Kim, Sanghag
2013-01-01
Background: Research has shown that interactions between young children's temperament and the quality of care they receive predict the emergence of positive and negative socioemotional developmental outcomes. This multimethod study addresses such interactions, using observed and mother-rated measures of difficult temperament, children's…
Computer Problems Can Infuriate Even the Most Tech Savvy
ERIC Educational Resources Information Center
Goldsborough, Reid
2004-01-01
Which high-tech products give you the most grief? Surprisingly, more people singled out TiVo and replay digital recording systems than personal computers, according to a recent survey by Best Buy. Nine percent of people said they found these TV devices difficult to use. The same percentage found PDAs (personal digital assistants) difficult. Only 2…
Hybridization and endangered species protection in the molecular era.
Wayne, Robert K; Shaffer, H Bradley
2016-06-01
After decades of discussion, there is little consensus on the extent to which hybrids between endangered and nonendangered species should be protected by US law. As increasingly larger, genome-scale data sets are developed, we can identify individuals and populations with even trace levels of genetic admixture, making the 'hybrid problem' all the more difficult. We developed a decision-tree framework for evaluating hybrid protection, including both the processes that produced hybrids (human-mediated or natural) and the ecological impact of hybrids on natural ecosystems. We then evaluated our decision tree for four case studies drawn from our own work and briefly discuss several other cases from the literature. Throughout, we highlight the management outcomes that our approach provides and the nuances of hybridization as a conservation problem. © 2016 John Wiley & Sons Ltd.
a Virtual Hub Brokering Approach for Integration of Historical and Modern Maps
NASA Astrophysics Data System (ADS)
Bruno, N.; Previtali, M.; Barazzetti, L.; Brumana, R.; Roncella, R.
2016-06-01
Geospatial data are today more and more widespread. Many different institutions, such as Geographical Institutes, Public Administrations, collaborative communities (e.g., OSM) and web companies, make available nowadays a large number of maps. Besides this cartography, projects of digitizing, georeferencing and web publication of historical maps have increasingly spread in the recent years. In spite of these variety and availability of data, information overload makes difficult their discovery and management: without knowing the specific repository where the data are stored, it is difficult to find the information required and problems of interconnection between different data sources and their restricted interoperability limit a wide utilization of available geo-data. This paper aims to describe some actions performed to assure interoperability between data, in particular spatial and geographic data, gathered from different data providers, with different features and referring to different historical periods. The article summarizes and exemplifies how, starting from projects of historical map digitizing and Historical GIS implementation, respectively for the Lombardy and for the city of Parma, the interoperability is possible in the framework of the ENERGIC OD project. The European project ENERGIC OD, thanks to a specific component - the virtual hub - based on a brokering framework, copes with the previous listed problems and allows the interoperability between different data sources.
Pergolizzi, Joseph V; Taylor, Robert; LeQuang, Jo Ann; Raffa, Robert B
2018-01-01
Proper management of severe pain represents one of the most challenging clinical dilemmas. Two equally important goals must be attained: the humanitarian/medical goal to relieve suffering and the societal/legal goal to not contribute to the drug abuse problem. This is an age-old problem, and the prevailing emphasis placed on one or the other goal has resulted in pendulum swings that have resulted in either undertreatment of pain or the current epidemic of misuse and abuse. In an effort to provide efficacious strong pain relievers (opioids) that are more difficult to abuse by the most dangerous routes of administration, pharmaceutical companies are developing products in which the opioid is manufactured in a formulation that is designed to be tamper resistant. Such a product is known as an abuse-deterrent formulation (ADF). ADF opioid products are designed to deter or resist abuse by making it difficult to tamper with the product and extracting the opioid for inhalation or injection. To date, less than a dozen opioid formulations have been approved by the US Food and Drug Administration to carry specific ADF labeling, but this number will likely increase in the coming years. Most of these products are extended-release formulations.
Interpretations of Quantum Theory in the Light of Modern Cosmology
NASA Astrophysics Data System (ADS)
Castagnino, Mario; Fortin, Sebastian; Laura, Roberto; Sudarsky, Daniel
2017-11-01
The difficult issues related to the interpretation of quantum mechanics and, in particular, the "measurement problem" are revisited using as motivation the process of generation of structure from quantum fluctuations in inflationary cosmology. The unessential mathematical complexity of the particular problem is bypassed, facilitating the discussion of the conceptual issues, by considering, within the paradigm set up by the cosmological problem, another problem where symmetry serves as a focal point: a simplified version of Mott's problem.
THE FOREMAN PROBLEM IN JAPANESE INDUSTRY.
ERIC Educational Resources Information Center
THURLEY, KEITH
BRITAIN STUDIED SUPERVISORY TRAINING IN JAPAN, IN ORDER TO GAIN INSIGHT INTO ITS OWN TRAINING PROBLEMS. TRADITIONAL SUPERVISION IN JAPANESE INDUSTRY HAD PRODUCED INCAPABLE FOREMEN THROUGH SENIORITY PROMOTION, CAUSED DIFFICULT RELATIONSHIPS BECAUSE OF AUTHORITARIAN ATTITUDES, AND FAILED TO CLARIFY AUTHORITY ROLES. THE GOVERNMENT RECOMMENDED MORE…
Zoonotic diseases: health aspects of Canadian geese.
Dieter, R A; Dieter, R S; Dieter, R A; Gulliver, G
2001-11-01
Review zoonotic diseases associated with Canadian geese. Review article: A review of the multiple physical, microbiologic and safety concerns, and methods used in controlling this potential problem. Over the last decade the Canadian goose population (protected by international treaties and protection acts) has increased rapidly such that in many cities they have become a pest rather than an admired wild bird. Their increasing numbers have caused a number of potential healthcare concerns including: physical, bacterial, parasitic, allergic and viral potential problems. The Canadian goose fecal droppings of one per minute have caused falls and the flying geese have caused air traffic accidents. Bacterial concerns, including botulism, salmonella and E. coli have all been reviewed and presented concerns. The viral Newcastle disease may be detected with hemagglutination studies and the Giardia psittaci parasites have been repeatedly found in their droppings. The Cryptosporidium parvum oocytes have been present on stool study. Definite links to human infectious diseases have been difficult to prove. Revision of the current laws and new control programs must be developed.
Cognitive Load Mediates the Effect of Emotion on Analytical Thinking.
Trémolière, Bastien; Gagnon, Marie-Ève; Blanchette, Isabelle
2016-11-01
Although the detrimental effect of emotion on reasoning has been evidenced many times, the cognitive mechanism underlying this effect remains unclear. In the present paper, we explore the cognitive load hypothesis as a potential explanation. In an experiment, participants solved syllogistic reasoning problems with either neutral or emotional contents. Participants were also presented with a secondary task, for which the difficult version requires the mobilization of cognitive resources to be correctly solved. Participants performed overall worse and took longer on emotional problems than on neutral problems. Performance on the secondary task, in the difficult version, was poorer when participants were reasoning about emotional, compared to neutral contents, consistent with the idea that processing emotion requires more cognitive resources. Taken together, the findings afford evidence that the deleterious effect of emotion on reasoning is mediated by cognitive load.
College Basketball on the Line.
ERIC Educational Resources Information Center
Suggs, Welch
1999-01-01
The National Collegiate Athletic Association (NCAA) has convened a working group to address problems in recruiting, gambling, academic standards, and other corrupt practices in college basketball programs. Such problems are neither new nor unique to basketball, and changing college sports has proven to be difficult. Recommendations are anticipated…
Teaching the Pressure-Flow Hypothesis of Phloem Transport in a Problem-Solving Session
ERIC Educational Resources Information Center
Clifford, Paul
2004-01-01
Problem solving is an ideal learning strategy, especially for topics that are perceived as difficult to teach. As an example, a format is described for a problem-solving session designed to help students understand the pressure-flow hypothesis of phloem transport in plants. Five key facts and their discussion can lead to the conclusion that a…
A Comparative Analysis of Word Problems in Selected United States and Russian First Grade Textbooks
ERIC Educational Resources Information Center
Grishchenko, Svetlana
2009-01-01
The purpose of this study was to explore word problems as a subject matter in mathematics textbook curricula. The motivation for the study derived from the following evidence: (a) American students find some word problems are more difficult than others (Garcia, Jimenez, & Hess, 2006; Riley & Green, 1988; Stern, 2001), and (b) one of the…
Preschoolers Grow Their Brains: Shifting Mindsets for Greater Resiliency and Better Problem Solving
ERIC Educational Resources Information Center
Pawlina, Shelby; Stanford, Christie
2011-01-01
Challenges, mistakes, and problems are inherent every day in learning activities and social interactions. How children think about and respond to those difficult situations has an impact on how they see themselves as being able to shape their own learning and on how they handle the next problem that comes their way. Building resilience means…
ERIC Educational Resources Information Center
Lehr, Susan; Lehr, Robert
This monograph aims to assist parents in dealing with behavior problems of children with disabilities. It begins with a case history of an 8-year-old girl with learning disabilities, emotional problems, and behavior problems and her parents' advocacy efforts to obtain an appropriate educational environment for her. Aversive interventions are…
Vortex generator design for aircraft inlet distortion as a numerical optimization problem
NASA Technical Reports Server (NTRS)
Anderson, Bernhard H.; Levy, Ralph
1991-01-01
Aerodynamic compatibility of aircraft/inlet/engine systems is a difficult design problem for aircraft that must operate in many different flight regimes. Takeoff, subsonic cruise, supersonic cruise, transonic maneuvering, and high altitude loiter each place different constraints on inlet design. Vortex generators, small wing like sections mounted on the inside surfaces of the inlet duct, are used to control flow separation and engine face distortion. The design of vortex generator installations in an inlet is defined as a problem addressable by numerical optimization techniques. A performance parameter is suggested to account for both inlet distortion and total pressure loss at a series of design flight conditions. The resulting optimization problem is difficult since some of the design parameters take on integer values. If numerical procedures could be used to reduce multimillion dollar development test programs to a small set of verification tests, numerical optimization could have a significant impact on both cost and elapsed time to design new aircraft.
A New Classification of Endodontic-Periodontal Lesions
Al-Fouzan, Khalid S.
2014-01-01
The interrelationship between periodontal and endodontic disease has always aroused confusion, queries, and controversy. Differentiating between a periodontal and an endodontic problem can be difficult. A symptomatic tooth may have pain of periodontal and/or pulpal origin. The nature of that pain is often the first clue in determining the etiology of such a problem. Radiographic and clinical evaluation can help clarify the nature of the problem. In some cases, the influence of pulpal pathology may cause the periodontal involvement and vice versa. The simultaneous existence of pulpal problems and inflammatory periodontal disease can complicate diagnosis and treatment planning. An endo-perio lesion can have a varied pathogenesis which ranges from simple to relatively complex one. The differential diagnosis of endodontic and periodontal diseases can sometimes be difficult, but it is of vital importance to make a correct diagnosis for providing the appropriate treatment. This paper aims to discuss a modified clinical classification to be considered for accurately diagnosing and treating endo-perio lesion. PMID:24829580
A new classification of endodontic-periodontal lesions.
Al-Fouzan, Khalid S
2014-01-01
The interrelationship between periodontal and endodontic disease has always aroused confusion, queries, and controversy. Differentiating between a periodontal and an endodontic problem can be difficult. A symptomatic tooth may have pain of periodontal and/or pulpal origin. The nature of that pain is often the first clue in determining the etiology of such a problem. Radiographic and clinical evaluation can help clarify the nature of the problem. In some cases, the influence of pulpal pathology may cause the periodontal involvement and vice versa. The simultaneous existence of pulpal problems and inflammatory periodontal disease can complicate diagnosis and treatment planning. An endo-perio lesion can have a varied pathogenesis which ranges from simple to relatively complex one. The differential diagnosis of endodontic and periodontal diseases can sometimes be difficult, but it is of vital importance to make a correct diagnosis for providing the appropriate treatment. This paper aims to discuss a modified clinical classification to be considered for accurately diagnosing and treating endo-perio lesion.
Application of the Water Needs Index: Can Tho City, Mekong Delta, Vietnam
NASA Astrophysics Data System (ADS)
Moglia, Magnus; Neumann, Luis E.; Alexander, Kim S.; Nguyen, Minh N.; Sharma, Ashok K.; Cook, Stephen; Trung, Nguyen H.; Tuan, Dinh D. A.
2012-10-01
SummaryProvision of urban water supplies to rapidly growing cities of South East Asia is difficult because of increasing demand for limited water supplies, periodic droughts, and depletion and contamination of surface and groundwater. In such adverse environments, effective policy and planning processes are required to secure adequate water supplies. Developing a Water Needs Index reveals key elements of the complex urban water supply by means of a participatory approach for rapid and interdisciplinary assessment. The index uses deliberative interactions with stakeholders to create opportunities for mutual understanding, confirmation of constructs and capacity building of all involved. In Can Tho City, located at the heart of the Mekong delta in Vietnam, a Water Needs Index has been developed with local stakeholders. The functional attributes of the Water Needs Index at this urban scale have been critically appraised. Systemic water issues, supply problems, health issues and inadequate, poorly functioning infrastructure requiring attention from local authorities have been identified. Entrenched social and economic inequities in access to water and sanitation, as well as polluting environmental management practices has caused widespread problems for urban populations. The framework provides a common language based on systems thinking, increased cross-sectoral communication, as well as increased recognition of problem issues; this ought to lead to improved urban water management. Importantly, the case study shows that the approach can help to overcome biases of local planners based on their limited experience (information black spots), to allow them to address problems experienced in all areas of the city.
ERIC Educational Resources Information Center
Ohio Commission on Dispute Resolution and Conflict Management, Columbus.
Conflict is a natural and inevitable part of living, but managing conflict is difficult for many people because they have not been taught how to resolve differences in cooperative, nonviolent ways. Communication problems can lead to misunderstanding and make conflicts more difficult to resolve. The Governor of Ohio has designated May 1-7, 2000 as…
Easing the Transition from Schooling to Work. New Directions for Community Colleges, Number 16.
ERIC Educational Resources Information Center
Silberman, Harry F., Ed.; Ginsburg, Mark B., Ed.
1976-01-01
The transition from schooling to work has been recognized as a difficult one. As society has become more modernized, the problem of transition has become even more aggravated. American postsecondary education has a role to play in making this transition less difficult, and in integrating the educational process into the world of work. This…
ERIC Educational Resources Information Center
Maina, Michael P.; Maina, Julie Schlegel; Hunt, Kevin
2016-01-01
Often students have a difficult time when asked to use critical thinking skills to solve a problem. Perhaps students have a difficult time adjusting because teachers frequently tell them exactly what to do and how to do it. When asked to use critical thinking skills, students may suddenly become confused and discouraged because the teacher no…
Medical and psychosocial experiences of family caregivers with children fed enterally at home.
Enrione, Evelyn B; Thomlison, Barbara; Rubin, Aviva
2005-01-01
Pediatric home enteral nutrition (HEN) studies that evaluate the psychosocial aspects of caregiving are limited. Overlooking the psychosocial needs of the caregiver may result in negative outcomes such as lack of adherence to the HEN regimen. This study determined whether caregivers report psychosocial situations more frequent and difficult to manage than medical situations. A questionnaire, which identified 10 psychosocial and 10 medical issues related to pediatric HEN, was mailed to 150 caregivers (37 responded), who rated the statements for frequency and difficulty. Each statement was ranked from most frequent/difficult to least frequent/difficult by mean cross-product score (frequency x difficulty). To indicate overall burden, a medical total composite score (MTCS) and a psychosocial total composite score (PTCS) were calculated by summing the cross-products of the respective problems. Paired t tests compared MTCS to PTCS and also the psychosocial frequency means and difficulty means to the same for the medical problems. Of the top 10 problems, 7 were psychosocial, whereas 3 were medical. Caregivers reported incidences of psychosocial problems more frequently (p < .003) than medical problems, and they had more difficulty (p < .001) with the psychosocial situations than with the medical ones. The PTCS was significantly higher (p < .001) than the MTCS. The psychosocial situations were perceived as causing a greater burden and greater difficulty in coping with everyday life. Health professionals need to understand and address the psychosocial difficulties of the caregiver in order to provide support for the caregiver and promote positive growth and development of the child.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baker, Kyri; Toomey, Bridget
Evolving power systems with increasing levels of stochasticity call for a need to solve optimal power flow problems with large quantities of random variables. Weather forecasts, electricity prices, and shifting load patterns introduce higher levels of uncertainty and can yield optimization problems that are difficult to solve in an efficient manner. Solution methods for single chance constraints in optimal power flow problems have been considered in the literature, ensuring single constraints are satisfied with a prescribed probability; however, joint chance constraints, ensuring multiple constraints are simultaneously satisfied, have predominantly been solved via scenario-based approaches or by utilizing Boole's inequality asmore » an upper bound. In this paper, joint chance constraints are used to solve an AC optimal power flow problem while preventing overvoltages in distribution grids under high penetrations of photovoltaic systems. A tighter version of Boole's inequality is derived and used to provide a new upper bound on the joint chance constraint, and simulation results are shown demonstrating the benefit of the proposed upper bound. The new framework allows for a less conservative and more computationally efficient solution to considering joint chance constraints, specifically regarding preventing overvoltages.« less
Methanol shutdowns cause anxiety
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, N.
1996-10-23
European methanol players face an anxious few weeks as unscheduled outages combine with planned turnarounds to make an increasingly tight market. Global markets are also described as tightening, with production problems widely reported in North America. Several European producers were in the middle of shutdown periods when problems at Condea`s 400,000-m.t./year unit at Wesseling, Germany reportedly caused production to run at only 50% of capacity. In addition, the methanol plant at the Leuna refinery is said to be operating at only 60% of capacity, and one producer has had to extend a turnaround period. River levels in Germany are alsomore » low, putting pressure on shipments from Rotterdam. {open_quotes}This is a very difficult situation and we`re living hand to mouth,{close_quotes} says one producer. Producer sources report bids from consumers up to DM280/m.t. T2 fob Rotterdam, but they are unable to obtain extra product. Derivatives makers may also face problems: One methyl tert-butyl ether producer predicts prices {open_quotes}may hit the roof{close_quotes} once feedstock sourcing problems hit home.« less
Research on allocation efficiency of the daisy chain allocation algorithm
NASA Astrophysics Data System (ADS)
Shi, Jingping; Zhang, Weiguo
2013-03-01
With the improvement of the aircraft performance in reliability, maneuverability and survivability, the number of the control effectors increases a lot. How to distribute the three-axis moments into the control surfaces reasonably becomes an important problem. Daisy chain method is simple and easy to be carried out in the design of the allocation system. But it can not solve the allocation problem for entire attainable moment subset. For the lateral-directional allocation problem, the allocation efficiency of the daisy chain can be directly measured by the area of its subset of attainable moments. Because of the non-linear allocation characteristic, the subset of attainable moments of daisy-chain method is a complex non-convex polygon, and it is difficult to solve directly. By analyzing the two-dimensional allocation problems with a "micro-element" idea, a numerical calculation algorithm is proposed to compute the area of the non-convex polygon. In order to improve the allocation efficiency of the algorithm, a genetic algorithm with the allocation efficiency chosen as the fitness function is proposed to find the best pseudo-inverse matrix.
Exact solution of large asymmetric traveling salesman problems.
Miller, D L; Pekny, J F
1991-02-15
The traveling salesman problem is one of a class of difficult problems in combinatorial optimization that is representative of a large number of important scientific and engineering problems. A survey is given of recent applications and methods for solving large problems. In addition, an algorithm for the exact solution of the asymmetric traveling salesman problem is presented along with computational results for several classes of problems. The results show that the algorithm performs remarkably well for some classes of problems, determining an optimal solution even for problems with large numbers of cities, yet for other classes, even small problems thwart determination of a provably optimal solution.
[Contemporary family systems--developments, problems, and possibilities].
Reich, Günter
2005-12-01
Contemporary forms of family life and their development are described. The thesis of the pluralism of family types as a historical new phenomenon is critically reviewed, with special consideration of the relationship between family life and working world. An increasing move away from the "fordistic model" of family life took place during the last two decades towards the "multilocal multigenerational family". This development is, among others, due to the increased life expectancy and the change in the population structure. Simultaneous to this the boundaries between family and working world become more permeable. If the stability of employments decreases and the mobility of employees increases in a large scale, is discussed controversely. For an increasing number of families it becomes more and more difficult to make flexibility at work compatible with security for the children or to cope with the consequences of unemployment.
COPS: Large-scale nonlinearly constrained optimization problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bondarenko, A.S.; Bortz, D.M.; More, J.J.
2000-02-10
The authors have started the development of COPS, a collection of large-scale nonlinearly Constrained Optimization Problems. The primary purpose of this collection is to provide difficult test cases for optimization software. Problems in the current version of the collection come from fluid dynamics, population dynamics, optimal design, and optimal control. For each problem they provide a short description of the problem, notes on the formulation of the problem, and results of computational experiments with general optimization solvers. They currently have results for DONLP2, LANCELOT, MINOS, SNOPT, and LOQO.
The evolution of tooth wear indices
2008-01-01
Tooth wear—attrition, erosion and abrasion—is perceived internationally as an ever-increasing problem. Clinical and epidemiological studies, however, are difficult to interpret and compare due to differences in terminology and the large number of indices that have been developed for diagnosing, grading and monitoring dental hard tissue loss. These indices have been designed to identify increasing severity and are usually numerical. Some record lesions on an aetiological basis (e.g. erosion indices), others record lesions irrespective of aetiology (tooth wear indices); none have universal acceptance, complicating the evaluation of the true increase in prevalence reported. This article considers the ideal requirements for an erosion index. It reviews the literature to consider how current indices have evolved and discusses if these indices meet the clinical and research needs of the dental profession. PMID:17701430
The emerging obesity problem in Latin America.
Cuevas, Ada; Alvarez, Verónica; Olivos, Cristina
2009-03-01
Obesity and overweight prevalence is increasing rapidly in Latin America. This increase has been attributed to lifestyle changes occurring in recent decades related to rapid socioeconomic development, including a more Westernized diet, physical inactivity, urbanization, rural-urban migration and some maternal-fetal factors. In addition, genetic factors may have a role, inducing a higher predisposition to accumulate abdominal fat and develop metabolic syndrome. This increase in obesity and metabolic syndrome is leading to higher morbidity and mortality due to Type 2 diabetes and cardiovascular disease. In a few poor countries, obesity coexists with undernutrition, making the situation even more difficult. Global intervention, from both governments and nongovernmental organizations, is necessary. They must play an active role, monitoring the food market and facilitating community-based initiatives that promote a healthy lifestyle.
Jani, Nrupa; Vu, Lung; Kay, Lynnette; Habtamu, Kassahun; Kalibala, Samuel
2016-01-01
Introduction Ethiopia is experiencing an increasingly urban HIV epidemic, alongside a rise in urban adolescent migration. Adolescent migrants are often confronted by unique social challenges, including living in a difficult environment, abuse and mental health problems. These issues can increase adolescents’ vulnerability to HIV and compromise their capacity to protect themselves and others from HIV. We piloted and assessed the effects of a targeted psychosocial intervention to reduce mental health problems and improve HIV-related outcomes among migrant adolescents in Addis Ababa. Methods A pre- and post-comparison design was used in a cohort of 576 female and 154 male migrant adolescents aged 15 to 18 years in Addis Ababa receiving services from two service delivery organizations, Biruh Tesfa and Retrak. We implemented a three-month client-centred, counsellor-delivered psychosocial intervention, based on findings from formative research among the same target population, to address participants’ increased vulnerability to HIV. The intervention package comprised individual, group and creative arts therapy counselling sessions. Key outcome indicators included anxiety, depression, aggressive behaviour, attention problems, social problems, knowledge of HIV, safer sex practices and use of sexual health services. Longitudinal data analysis (McNemar test and random effects regression) was used to assess changes over time in key indicators by gender. Results For females, aggressive behaviour decreased by 60% (adjusted odds ratio (AOR): 0.4 (0.25 to 0.65)) and any mental health problem decreased by 50% (AOR: 0.5 (0.36 to 0.81)) from baseline to end line. In addition, knowledge of HIV increased by 60% (AOR: 1.6 (1.08 to 2.47)), knowledge of a place to test for HIV increased by 70% (AOR: 1.7 (1.12 to 2.51)) and HIV testing increased by 80% (AOR: 1.8 (1.13 to 2.97)). For males, HIV knowledge increased by 110% (AOR: 2.1 (1.1 to 3.94)), knowledge of a place to test for HIV increased by 290% (AOR: 3.9 (1.02 to 14.9)), HIV testing increased by 630% (AOR: 7.3 (2.6 to 20.7)) and use of sexual health services increased by 220% (AOR: 3.2 (1.62 to 6.27)). We did not find any significant reduction in mental health problems among male adolescents. Conclusions Our findings suggest that a psychosocial intervention was associated with increased knowledge and uptake of HIV and sexual health services among both male and female migrant adolescents and with reduced mental health problems among female adolescents. Mental health problems varied significantly for male and female adolescents, suggesting that future interventions should be tailored to address their different needs and would benefit from intensive follow-up efforts. PMID:27443267
Jani, Nrupa; Vu, Lung; Kay, Lynnette; Habtamu, Kassahun; Kalibala, Samuel
2016-01-01
Ethiopia is experiencing an increasingly urban HIV epidemic, alongside a rise in urban adolescent migration. Adolescent migrants are often confronted by unique social challenges, including living in a difficult environment, abuse and mental health problems. These issues can increase adolescents' vulnerability to HIV and compromise their capacity to protect themselves and others from HIV. We piloted and assessed the effects of a targeted psychosocial intervention to reduce mental health problems and improve HIV-related outcomes among migrant adolescents in Addis Ababa. A pre- and post-comparison design was used in a cohort of 576 female and 154 male migrant adolescents aged 15 to 18 years in Addis Ababa receiving services from two service delivery organizations, Biruh Tesfa and Retrak. We implemented a three-month client-centred, counsellor-delivered psychosocial intervention, based on findings from formative research among the same target population, to address participants' increased vulnerability to HIV. The intervention package comprised individual, group and creative arts therapy counselling sessions. Key outcome indicators included anxiety, depression, aggressive behaviour, attention problems, social problems, knowledge of HIV, safer sex practices and use of sexual health services. Longitudinal data analysis (McNemar test and random effects regression) was used to assess changes over time in key indicators by gender. For females, aggressive behaviour decreased by 60% (adjusted odds ratio (AOR): 0.4 (0.25 to 0.65)) and any mental health problem decreased by 50% (AOR: 0.5 (0.36 to 0.81)) from baseline to end line. In addition, knowledge of HIV increased by 60% (AOR: 1.6 (1.08 to 2.47)), knowledge of a place to test for HIV increased by 70% (AOR: 1.7 (1.12 to 2.51)) and HIV testing increased by 80% (AOR: 1.8 (1.13 to 2.97)). For males, HIV knowledge increased by 110% (AOR: 2.1 (1.1 to 3.94)), knowledge of a place to test for HIV increased by 290% (AOR: 3.9 (1.02 to 14.9)), HIV testing increased by 630% (AOR: 7.3 (2.6 to 20.7)) and use of sexual health services increased by 220% (AOR: 3.2 (1.62 to 6.27)). We did not find any significant reduction in mental health problems among male adolescents. Our findings suggest that a psychosocial intervention was associated with increased knowledge and uptake of HIV and sexual health services among both male and female migrant adolescents and with reduced mental health problems among female adolescents. Mental health problems varied significantly for male and female adolescents, suggesting that future interventions should be tailored to address their different needs and would benefit from intensive follow-up efforts.
Generating Data Flow Programs from Nonprocedural Specifications.
1983-03-01
With the I-structures, Gajski points out, it is difficult to know ahead of time the optimal memory allocation scheme to pertition large arrays. amory...contention problems may occur for frequently accessed elements stored in the sam memory module. Gajski observes that these are the same problem which
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haghighat, A.; Sjoden, G.E.; Wagner, J.C.
In the past 10 yr, the Penn State Transport Theory Group (PSTTG) has concentrated its efforts on developing accurate and efficient particle transport codes to address increasing needs for efficient and accurate simulation of nuclear systems. The PSTTG's efforts have primarily focused on shielding applications that are generally treated using multigroup, multidimensional, discrete ordinates (S{sub n}) deterministic and/or statistical Monte Carlo methods. The difficulty with the existing public codes is that they require significant (impractical) computation time for simulation of complex three-dimensional (3-D) problems. For the S{sub n} codes, the large memory requirements are handled through the use of scratchmore » files (i.e., read-from and write-to-disk) that significantly increases the necessary execution time. Further, the lack of flexible features and/or utilities for preparing input and processing output makes these codes difficult to use. The Monte Carlo method becomes impractical because variance reduction (VR) methods have to be used, and normally determination of the necessary parameters for the VR methods is very difficult and time consuming for a complex 3-D problem. For the deterministic method, the authors have developed the 3-D parallel PENTRAN (Parallel Environment Neutral-particle TRANsport) code system that, in addition to a parallel 3-D S{sub n} solver, includes pre- and postprocessing utilities. PENTRAN provides for full phase-space decomposition, memory partitioning, and parallel input/output to provide the capability of solving large problems in a relatively short time. Besides having a modular parallel structure, PENTRAN has several unique new formulations and features that are necessary for achieving high parallel performance. For the Monte Carlo method, the major difficulty currently facing most users is the selection of an effective VR method and its associated parameters. For complex problems, generally, this process is very time consuming and may be complicated due to the possibility of biasing the results. In an attempt to eliminate this problem, the authors have developed the A{sup 3}MCNP (automated adjoint accelerated MCNP) code that automatically prepares parameters for source and transport biasing within a weight-window VR approach based on the S{sub n} adjoint function. A{sup 3}MCNP prepares the necessary input files for performing multigroup, 3-D adjoint S{sub n} calculations using TORT.« less
[Management of malnutrition in preschool children: the role of primary health care services].
Hoerée, Tom; Kolsteren, Patrick; Roberfroid, Dominique
2002-01-01
Although the prevalence of malnutrition in developing countries is decreasing, it is still a major problem for many children under five. As socio-economic conditions are the main determinants, a final solution for this problem can only be envisaged in the long run. Still, short-term strategies need to be defined in order to relieve the sufferings of individual children and their families. Understanding the problem and consequently formulating intervention programs at the local level remains a complex and difficult issue. The first reason being that the process of malnutrition expresses itself in different forms and with variable consequences. A second reason making malnutrition a complex problem is that the primary causes -- the interaction between insufficient food supply and the frequent recurrence of infectious diseases -- are determined by a multitude of factors of different natures. This complexity -- of its expressions, effects, and causality -- makes it difficult to get a global vision and understanding of the problem, which clearly impedes the definition of rational and integrated intervention strategies. Nevertheless, a better understanding of the pathophysiology of malnutrition and of the factors that influence the growth process in preschool age, will help to better direct actions. To this effect, a conceptual model will be built, based on recent insight in the process of malnutrition within this age group. From this model, two lines of action for increasing the chances of preschool children to express their initial growth potential, become apparent. A first series of activities could tackle the process that, via wasting and recurrence of infections, leads to an increased mortality risk. As timely intervention reduces the risk of depletion of energy reserves, these activities would also have an indirect impact on physical development. Elaborating strategies for secondary prevention and for treating severe cases belongs to the specific competence of the health sector. In the second line of action, the aim is to intervene before reserves are depleted. Here, primary prevention and health promotion are choice activities. This frame of reference will be used for analysing existing health programs for preschool children and how they propose to improve the management of malnutrition. This analysis will show that primary health care services can play a much more important role than usually attributed to them. Identifying these gaps and elaborating alternatives is the purpose of this article.
Classification of brain MRI with big data and deep 3D convolutional neural networks
NASA Astrophysics Data System (ADS)
Wegmayr, Viktor; Aitharaju, Sai; Buhmann, Joachim
2018-02-01
Our ever-aging society faces the growing problem of neurodegenerative diseases, in particular dementia. Magnetic Resonance Imaging provides a unique tool for non-invasive investigation of these brain diseases. However, it is extremely difficult for neurologists to identify complex disease patterns from large amounts of three-dimensional images. In contrast, machine learning excels at automatic pattern recognition from large amounts of data. In particular, deep learning has achieved impressive results in image classification. Unfortunately, its application to medical image classification remains difficult. We consider two reasons for this difficulty: First, volumetric medical image data is considerably scarcer than natural images. Second, the complexity of 3D medical images is much higher compared to common 2D images. To address the problem of small data set size, we assemble the largest dataset ever used for training a deep 3D convolutional neural network to classify brain images as healthy (HC), mild cognitive impairment (MCI) or Alzheimers disease (AD). We use more than 20.000 images from subjects of these three classes, which is almost 9x the size of the previously largest data set. The problem of high dimensionality is addressed by using a deep 3D convolutional neural network, which is state-of-the-art in large-scale image classification. We exploit its ability to process the images directly, only with standard preprocessing, but without the need for elaborate feature engineering. Compared to other work, our workflow is considerably simpler, which increases clinical applicability. Accuracy is measured on the ADNI+AIBL data sets, and the independent CADDementia benchmark.
Rugulies, Reiner; Martin, Marie H T; Garde, Anne Helene; Persson, Roger; Albertsen, Karen
2012-03-01
Exposure to deadlines at work is increasing in several countries and may affect health. We aimed to investigate cross-sectional and longitudinal associations between frequency of difficult deadlines at work and sleep quality. Study participants were knowledge workers, drawn from a representative sample of Danish employees who responded to a baseline questionnaire in 2006 (n = 363) and a follow-up questionnaire in 2007 (n = 302). Frequency of difficult deadlines was measured by self-report and categorized into low, intermediate, and high. Sleep quality was measured with a Total Sleep Quality Score and two indexes (Awakening Index and Disturbed Sleep Index) derived from the Karolinska Sleep Questionnaire. Analyses on the association between frequency of deadlines and sleep quality scores were conducted with multiple linear regression models, adjusted for potential confounders. In addition, we used multiple logistic regression models to analyze whether frequency of deadlines at baseline predicted caseness of sleep problems at follow-up among participants free of sleep problems at baseline. Frequent deadlines were cross-sectionally and longitudinally associated with poorer sleep quality on all three sleep quality measures. Associations in the longitudinal analyses were greatly attenuated when we adjusted for baseline sleep quality. The logistic regression analyses showed that frequent deadlines at baseline were associated with elevated odds ratios for caseness of sleep problems at follow-up, however, confidence intervals were wide in these analyses. Frequent deadlines at work were associated with poorer sleep quality among Danish knowledge workers. We recommend investigating the relation between deadlines and health endpoints in large-scale epidemiologic studies. Copyright © 2011 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Strack, O. D. L.
2018-02-01
We present equations for new limitless analytic line elements. These elements possess a virtually unlimited number of degrees of freedom. We apply these new limitless analytic elements to head-specified boundaries and to problems with inhomogeneities in hydraulic conductivity. Applications of these new analytic elements to practical problems involving head-specified boundaries require the solution of a very large number of equations. To make the new elements useful in practice, an efficient iterative scheme is required. We present an improved version of the scheme presented by Bandilla et al. (2007), based on the application of Cauchy integrals. The limitless analytic elements are useful when modeling strings of elements, rivers for example, where local conditions are difficult to model, e.g., when a well is close to a river. The solution of such problems is facilitated by increasing the order of the elements to obtain a good solution. This makes it unnecessary to resort to dividing the element in question into many smaller elements to obtain a satisfactory solution.
NASA Astrophysics Data System (ADS)
Umbarkar, A. J.; Balande, U. T.; Seth, P. D.
2017-06-01
The field of nature inspired computing and optimization techniques have evolved to solve difficult optimization problems in diverse fields of engineering, science and technology. The firefly attraction process is mimicked in the algorithm for solving optimization problems. In Firefly Algorithm (FA) sorting of fireflies is done by using sorting algorithm. The original FA is proposed with bubble sort for ranking the fireflies. In this paper, the quick sort replaces bubble sort to decrease the time complexity of FA. The dataset used is unconstrained benchmark functions from CEC 2005 [22]. The comparison of FA using bubble sort and FA using quick sort is performed with respect to best, worst, mean, standard deviation, number of comparisons and execution time. The experimental result shows that FA using quick sort requires less number of comparisons but requires more execution time. The increased number of fireflies helps to converge into optimal solution whereas by varying dimension for algorithm performed better at a lower dimension than higher dimension.
An ethics dilemma: when parents and doctors disagree on the best treatment for the child.
Oppenheim, Daniel; Brugières, Laurence; Corradini, Nadège; Vivant, Florence; Hartmann, Olivier
2004-09-01
The increasing complexity of present day medicine--with highly effective and yet risky treatments, individual and collective expectations, and evolving ideological and cultural landmarks--often gives rise to difficult ethical problems. Specific meetings are valuable for understanding such problems, acquiring the relevant skills and for gaining and transmitting experience on how to solve them. Parents and doctors may disagree about what is the best treatment. Such a difference of opinion is not rare but usually a solution can easily be found. This is not the case when the child is treated for a severe illness and when there is no clearly defined or satisfactory treatment for him\\her. We present how a dramatic conflict arose between the parents and the doctors faced with such a case (mostly because the staff failed to understand early enough the psychological factors at the root of the father's demands), how clinical, institutional and ethical problems were analysed during a meeting, and how they were solved.
Euthanasia from the perspective of hospice care.
Gillett, G
1994-01-01
The hospice believes in the concept of a gentle and harmonious death. In most hospice settings there is also a rejection of active euthanasia. This set of two apparently conflicting principles can be defended on the basis of two arguments. The first is that doctors should not foster the intent to kill as part of their moral and clinical character. This allows proper sensitivity to the complex and difficult situation that arises in many of the most difficult terminal care situations. The second argument turns on the seduction of technological solutions to human problems and the slippery slope that may arise in the presence of a quick and convenient way of dealing with problems of death and dying.
Big data processing in the cloud - Challenges and platforms
NASA Astrophysics Data System (ADS)
Zhelev, Svetoslav; Rozeva, Anna
2017-12-01
Choosing the appropriate architecture and technologies for a big data project is a difficult task, which requires extensive knowledge in both the problem domain and in the big data landscape. The paper analyzes the main big data architectures and the most widely implemented technologies used for processing and persisting big data. Clouds provide for dynamic resource scaling, which makes them a natural fit for big data applications. Basic cloud computing service models are presented. Two architectures for processing big data are discussed, Lambda and Kappa architectures. Technologies for big data persistence are presented and analyzed. Stream processing as the most important and difficult to manage is outlined. The paper highlights main advantages of cloud and potential problems.
Self-inflicted injuries. Challenging knowledge, skill, and compassion.
Haswell, D E; Graham, M
1996-09-01
Self-inflicted injuries and other serious self-destructive behaviours are common and difficult to recognize, prevent, and manage. Although they have previously been understood as repeated, failed attempts at suicide, they are better understood as maladaptive coping strategies. Women who present repeatedly with self-inflicted injuries need help to control this self-destructive behaviour and substitute more positive coping strategies. Physicians also need help in working with patients who respond to problems in this way. The program is made up of two broad sections. The first section involves understanding the problem and its origins in post-traumatic stress disorders. The second section offers a practical approach to helping patients presenting with injuries inflict upon themselves. A deeper understanding of the etiology and management of repeated self-inflicted injuries will enable physicians to help patients with this difficult problem while minimizing their own anxiety and frustration.
Evaluating models of climate and forest vegetation
NASA Technical Reports Server (NTRS)
Clark, James S.
1992-01-01
Understanding how the biosphere may respond to increasing trace gas concentrations in the atmosphere requires models that contain vegetation responses to regional climate. Most of the processes ecologists study in forests, including trophic interactions, nutrient cycling, and disturbance regimes, and vital components of the world economy, such as forest products and agriculture, will be influenced in potentially unexpected ways by changing climate. These vegetation changes affect climate in the following ways: changing C, N, and S pools; trace gases; albedo; and water balance. The complexity of the indirect interactions among variables that depend on climate, together with the range of different space/time scales that best describe these processes, make the problems of modeling and prediction enormously difficult. These problems of predicting vegetation response to climate warming and potential ways of testing model predictions are the subjects of this chapter.
ERIC Educational Resources Information Center
Burns, Barbara A.; Jordan, Thomas M.
2006-01-01
Business managers are faced with complex decisions involving a wide range of issues--technical, social, environmental, and financial--and their interaction. Our education system focuses heavily on presenting structured problems and teaching students to apply a set of tools or methods to solve these problems. Yet the most difficult thing to teach…
When 95% Accurate Isn't: Exploring Bayes's Theorem
ERIC Educational Resources Information Center
CadwalladerOlsker, Todd D.
2011-01-01
Bayes's theorem is notorious for being a difficult topic to learn and to teach. Problems involving Bayes's theorem (either implicitly or explicitly) generally involve calculations based on two or more given probabilities and their complements. Further, a correct solution depends on students' ability to interpret the problem correctly. Most people…
Design and Implementation of the Game-Design and Learning Program
ERIC Educational Resources Information Center
Akcaoglu, Mete
2016-01-01
Design involves solving complex, ill-structured problems. Design tasks are consequently, appropriate contexts for children to exercise higher-order thinking and problem-solving skills. Although creating engaging and authentic design contexts for young children is difficult within the confines of traditional schooling, recently, game-design has…
Wilbur F. LaPage
1971-01-01
A critical look at outdoor recreation research and some underlying premises. The author focuses on the concept of culture as communication and how it influences our perception of problems and our search for solutions. Both outdoor recreation and science are viewed as subcultures that have their own bodies of mythology, making recreation problems more difficult to...
A Zone for Deliberation? Methodological Challenges in Fields of Political Unrest
ERIC Educational Resources Information Center
Westrheim, Kariane; Lillejord, Solvi
2007-01-01
This article outlines certain problems and challenges facing the qualitative researcher who enters fields that are either extremely difficult to access or potentially hostile towards outsiders. Problems and dilemmas in such contexts are highlighted by reference to fieldwork research among PKK (Kurdistan Worker's Party) guerrillas in North…
Measuring Avoidance and Inflexibility in Weight Related Problems
ERIC Educational Resources Information Center
Lillis, Jason; Hayes, Steven C.
2008-01-01
There is growing evidence that experiential avoidance and psychological inflexibility plays a role in a variety of clinical presentations, including health problems. The present study presents preliminary data on a new measure of these processes in relation to difficult weight-related thoughts, feelings, and actions: The Acceptance and Action…
Teaching Database Design with Constraint-Based Tutors
ERIC Educational Resources Information Center
Mitrovic, Antonija; Suraweera, Pramuditha
2016-01-01
Design tasks are difficult to teach, due to large, unstructured solution spaces, underspecified problems, non-existent problem solving algorithms and stopping criteria. In this paper, we comment on our approach to develop KERMIT, a constraint-based tutor that taught database design. In later work, we re-implemented KERMIT as EER-Tutor, and…
Sociodrama: Group Creative Problem Solving in Action.
ERIC Educational Resources Information Center
Riley, John F.
1990-01-01
Sociodrama is presented as a structured, yet flexible, method of encouraging the use of creative thinking to examine a difficult problem. An example illustrates the steps involved in putting sociodrama into action. Production techniques useful in sociodrama include the soliloquy, double, role reversal, magic shop, unity of opposites, and audience…
Guidance for modeling causes and effects in environmental problem solving
Armour, Carl L.; Williamson, Samuel C.
1988-01-01
Environmental problems are difficult to solve because their causes and effects are not easily understood. When attempts are made to analyze causes and effects, the principal challenge is organization of information into a framework that is logical, technically defensible, and easy to understand and communicate. When decisionmakers attempt to solve complex problems before an adequate cause and effect analysis is performed there are serious risks. These risks include: greater reliance on subjective reasoning, lessened chance for scoping an effective problem solving approach, impaired recognition of the need for supplemental information to attain understanding, increased chance for making unsound decisions, and lessened chance for gaining approval and financial support for a program/ Cause and effect relationships can be modeled. This type of modeling has been applied to various environmental problems, including cumulative impact assessment (Dames and Moore 1981; Meehan and Weber 1985; Williamson et al. 1987; Raley et al. 1988) and evaluation of effects of quarrying (Sheate 1986). This guidance for field users was written because of the current interest in documenting cause-effect logic as a part of ecological problem solving. Principal literature sources relating to the modeling approach are: Riggs and Inouye (1975a, b), Erickson (1981), and United States Office of Personnel Management (1986).
Solving geosteering inverse problems by stochastic Hybrid Monte Carlo method
Shen, Qiuyang; Wu, Xuqing; Chen, Jiefu; ...
2017-11-20
The inverse problems arise in almost all fields of science where the real-world parameters are extracted from a set of measured data. The geosteering inversion plays an essential role in the accurate prediction of oncoming strata as well as a reliable guidance to adjust the borehole position on the fly to reach one or more geological targets. This mathematical treatment is not easy to solve, which requires finding an optimum solution among a large solution space, especially when the problem is non-linear and non-convex. Nowadays, a new generation of logging-while-drilling (LWD) tools has emerged on the market. The so-called azimuthalmore » resistivity LWD tools have azimuthal sensitivity and a large depth of investigation. Hence, the associated inverse problems become much more difficult since the earth model to be inverted will have more detailed structures. The conventional deterministic methods are incapable to solve such a complicated inverse problem, where they suffer from the local minimum trap. Alternatively, stochastic optimizations are in general better at finding global optimal solutions and handling uncertainty quantification. In this article, we investigate the Hybrid Monte Carlo (HMC) based statistical inversion approach and suggest that HMC based inference is more efficient in dealing with the increased complexity and uncertainty faced by the geosteering problems.« less
The Difficult Gallbladder: A Safe Approach to a Dangerous Problem.
Santos, B Fernando; Brunt, L Michael; Pucci, Michael J
2017-06-01
Laparoscopic cholecystectomy is a common surgical procedure, and remains the gold standard for the management of benign gallbladder and biliary disease. While this procedure can be technically straightforward, it can also represent one of the most challenging operations facing surgeons. This dichotomy of a routine operation performed so commonly that poses such a hidden risk of severe complications, such as bile duct injury, must keep surgeons steadfast in the pursuit of safety. The "difficult gallbladder" requires strict adherence to the Culture of Safety in Cholecystectomy, which promotes safety first and assists surgeons in managing or avoiding difficult operative situations. This review will discuss the management of the difficult gallbladder and propose the use of subtotal fenestrating cholecystectomy as a definitive option during this dangerous situation.
Trading a Problem-solving Task
NASA Astrophysics Data System (ADS)
Matsubara, Shigeo
This paper focuses on a task allocation problem, especially cases where the task is to find a solution in a search problem or a constraint satisfaction problem. If the search problem is hard to solve, a contractor may fail to find a solution. Here, the more computational resources such as the CPU time the contractor invests in solving the search problem, the more a solution is likely to be found. This brings about a new problem that a contractee has to find an appropriate level of the quality in a task achievement as well as to find an efficient allocation of a task among contractors. For example, if the contractee asks the contractor to find a solution with certainty, the payment from the contractee to the contractor may exceed the contractee's benefit from obtaining a solution, which discourages the contractee from trading a task. However, solving this problem is difficult because the contractee cannot ascertain the contractor's problem-solving ability such as the amount of available resources and knowledge (e.g. algorithms, heuristics) or monitor what amount of resources are actually invested in solving the allocated task. To solve this problem, we propose a task allocation mechanism that is able to choose an appropriate level of the quality in a task achievement and prove that this mechanism guarantees that each contractor reveals its true information. Moreover, we show that our mechanism can increase the contractee's utility compared with a simple auction mechanism by using computer simulation.
Exploring the Lived Experience of Difficult Sleep and Good Sleep Among Psychiatric Inpatients.
Zust, Barbara Lois; Gruenberg, Marjorie E; Sendelbach, Susan Ellen
2016-01-01
The purpose of this qualitative study was to explore psychiatric inpatients' reflections on their experiences with sleep throughout their lives. Fourteen patients in an acute care behavioral health unit agreed to participate in this study. Participants met individually with a researcher to reflect on times in their lives when they experienced good sleep; times when they had difficulty sleeping; and times when difficult sleep was resolved. The major findings of the study indicated that feeling alone with life problems triggered difficult sleep; while feelings of belonging and purpose were associated with good sleep.
Autopilot, Mind Wandering, and the Out of the Loop Performance Problem
Gouraud, Jonas; Delorme, Arnaud; Berberian, Bruno
2017-01-01
To satisfy the increasing demand for safer critical systems, engineers have integrated higher levels of automation, such as glass cockpits in aircraft, power plants, and driverless cars. These guiding principles relegate the operator to a monitoring role, increasing risks for humans to lack system understanding. The out of the loop performance problem arises when operators suffer from complacency and vigilance decrement; consequently, when automation does not behave as expected, understanding the system or taking back manual control may be difficult. Close to the out of the loop problem, mind wandering points to the propensity of the human mind to think about matters unrelated to the task at hand. This article reviews the literature related to both mind wandering and the out of the loop performance problem as it relates to task automation. We highlight studies showing how these phenomena interact with each other while impacting human performance within highly automated systems. We analyze how this proximity is supported by effects observed in automated environment, such as decoupling, sensory attention, and cognitive comprehension decrease. We also show that this link could be useful for detecting out of the loop situations through mind wandering markers. Finally, we examine the limitations of the current knowledge because many questions remain open to characterize interactions between out of the loop, mind wandering, and automation. PMID:29051723
Atmospheric corrosion of metals in industrial city environment.
Kusmierek, Elzbieta; Chrzescijanska, Ewa
2015-06-01
Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust.
Disordered communication and grieving in deaf member families.
Sloman, L; Springer, S; Vachon, M L
1993-06-01
When a deaf child is born to hearing parents, a grieving process is initiated in the parents. Unresolved grieving over their child's deafness often makes it difficult for hearing parents to accept the importance of signing, thus increasing the child's problems--a further source of grief for these parents. Clinical illustrations are provided of (1) the reciprocal relationship between disruption of the mourning process and disturbance of communication between family members, and (2) the transmission of the dysfunctional relationship between hearing parents and deaf children to the subsequent relationship between the deaf children, when they reach adulthood, and their hearing children.
Automated visual imaging interface for the plant floor
NASA Astrophysics Data System (ADS)
Wutke, John R.
1991-03-01
The paper will provide an overview of the challenges facing a user of automated visual imaging (" AVI" ) machines and the philosophies that should be employed in designing them. As manufacturing tools and equipment become more sophisticated it is increasingly difficult to maintain an efficient interaction between the operator and machine. The typical user of an AVI machine in a production environment is technically unsophisticated. Also operator and machine ergonomics are often a neglected or poorly addressed part of an efficient manufacturing process. This paper presents a number of man-machine interface design techniques and philosophies that effectively solve these problems.
Optical polarization: plenty of room for surprise
NASA Astrophysics Data System (ADS)
Chenault, David
2012-10-01
Solutions to difficult problems in complex environments frequently require methodical approaches and detailed research plans. Fortunately, there is still room for serendipity in disciplines that are relatively mature and well understood. As a case in point, optical sensors that exploit polarized light have matured greatly and the discipline of optical polarization has grown substantially in scope and applications over the last ten years. In spite of this increased understanding, polarization signatures are frequently not well understood. A good example is polarization in the animal kingdom. The potential for polarimetric monitoring of moose populations, and other applications, will be discussed.
Characterizing Marine Soundscapes.
Erbe, Christine; McCauley, Robert; Gavrilov, Alexander
2016-01-01
The study of marine soundscapes is becoming widespread and the amount of data collected is increasing rapidly. Data owners (typically academia, industry, government, and defense) are negotiating data sharing and generating potential for data syntheses, comparative studies, analyses of trends, and large-scale and long-term acoustic ecology research. A problem is the lack of standards and commonly agreed protocols for the recording of marine soundscapes, data analysis, and reporting that make a synthesis and comparison of results difficult. We provide a brief overview of the components in a marine soundscape, the hard- and software tools for recording and analyzing marine soundscapes, and common reporting formats.
Ground-state energies and charge radii of medium-mass nuclei in the unitary-model-operator approach
NASA Astrophysics Data System (ADS)
Miyagi, Takayuki; Abe, Takashi; Okamoto, Ryoji; Otsuka, Takaharu
2014-09-01
In nuclear structure theory, one of the most fundamental problems is to understand the nuclear structure based on nuclear forces. This attempt has been enabled due to the progress of the computational power and nuclear many-body approaches. However, it is difficult to apply the first-principle methods to medium-mass region, because calculations demand the huge model space as increasing the number of nucleons. The unitary-model-operator approach (UMOA) is one of the methods which can be applied to medium-mass nuclei. The essential point of the UMOA is to construct the effective Hamiltonian which does not induce the two-particle-two-hole excitations. A many-body problem is reduced to the two-body subsystem problem in an entire many-body system with the two-body effective interaction and one-body potential determined self-consistently. In this presentation, we will report the numerical results of ground-state energies and charge radii of 16O, 40Ca, and 56Ni in the UMOA, and discuss the saturation property by comparing our results with those in the other many-body methods and also experimental data. In nuclear structure theory, one of the most fundamental problems is to understand the nuclear structure based on nuclear forces. This attempt has been enabled due to the progress of the computational power and nuclear many-body approaches. However, it is difficult to apply the first-principle methods to medium-mass region, because calculations demand the huge model space as increasing the number of nucleons. The unitary-model-operator approach (UMOA) is one of the methods which can be applied to medium-mass nuclei. The essential point of the UMOA is to construct the effective Hamiltonian which does not induce the two-particle-two-hole excitations. A many-body problem is reduced to the two-body subsystem problem in an entire many-body system with the two-body effective interaction and one-body potential determined self-consistently. In this presentation, we will report the numerical results of ground-state energies and charge radii of 16O, 40Ca, and 56Ni in the UMOA, and discuss the saturation property by comparing our results with those in the other many-body methods and also experimental data. The part of numerical calculation has been done on the NEC SX8R at RCNP, Osaka University. This work was supported in part by MEXT SPIRE and JICFuS. It was also supported in part by the Program in part for Leading Graduate Schools, MEXT, Japan.
Raspollini, Maria Rosaria; Paglierani, Milena; Taddei, Gian Luigi
2009-03-01
Transitional cell carcinoma (TCC) of the ovary is a recently recognized subtype of ovarian surface epithelial-stromal cancer that morphologically resembles a TCC of the bladder. The most frequent metastases to ovaries come from the gastrointestinal tract and from breast carcinoma, but metastatic TCCs from the urinary tract to the ovary have been reported. TCC of the bladder is the sixth most common cancer in European and North American countries and its incidence has been increasing. We recently observed a woman, who previously had undergone endoscopic resection of a TCC of the bladder. She was affected by an ovarian bilateral tumor with features of malignant transitional cell tumor, characterized by papillae with multilayered transitional epithelium infiltrating the ovarian stroma. In this study, we showed the utility of WT1 and a panel of immunohistochemical markers in the difficult differential diagnosis between bladder and ovarian TCC.
The human influence on seabird nesting success: Conservation implications
Anderson, D.W.; Keith, J.O.
1980-01-01
Based on studies of brown pelicans Pelecanus occidentalis californicus and Heermann's gulls Larus heermanni, disturbances by recreationists, educational groups, local fishermen and scientists alike can be seriously disruptive and damaging to breeding seabirds in the Gulf of California and off the west coast of Baja California. Similar instances have been identified throughout the world?the problem is not difficult to document, but it is difficult to eliminate. The increasing human-seabird contacts on islands in the Gulf of California and along the west coast of Baja California raise serious questions and immediate concern about the continued preservation of nesting colonies of marine birds in those areas. Conservation measures must consider the extreme sensitivity of many seabirds to the inter- and intraspecific behavioural imbalances created by human disturbances. In some cases, total exclusion of humans may be required; in others, limited access might be possible under closely managed conditions at certain times of the year. A symbiotic relationship between seabird conservation, legitimate research and tourism should be the desired goal.
Bridging the Gap Between Planning and Scheduling
NASA Technical Reports Server (NTRS)
Smith, David E.; Frank, Jeremy; Jonsson, Ari K.; Norvig, Peter (Technical Monitor)
2000-01-01
Planning research in Artificial Intelligence (AI) has often focused on problems where there are cascading levels of action choice and complex interactions between actions. In contrast. Scheduling research has focused on much larger problems where there is little action choice, but the resulting ordering problem is hard. In this paper, we give an overview of M planning and scheduling techniques, focusing on their similarities, differences, and limitations. We also argue that many difficult practical problems lie somewhere between planning and scheduling, and that neither area has the right set of tools for solving these vexing problems.
Using literature to help physician-learners understand and manage "difficult" patients.
Shapiro, J; Lie, D
2000-07-01
Despite significant clinical and research efforts aimed at recognizing and managing "difficult" patients, such patients remain a frustrating experience for many clinicians. This is especially true for primary care residents, who are required to see a significant volume of patients with diverse and complex problems, but who may not have adequate training and life experience to enable them to deal with problematic doctor-patient situations. Literature--short stories, poems, and patient narratives--is a little-explored educational tool to help residents in understanding and working with difficult patients. In this report, the authors examine the mechanics of using literature to teach about difficult patients, including structuring the learning environment, establishing learning objectives, identifying teaching resources and appropriate pedagogic methods, and incorporating creative writing assignments. They also present an illustrative progression of a typical literature-based teaching session about a difficult patient.
Efficient authentication scheme based on near-ring root extraction problem
NASA Astrophysics Data System (ADS)
Muthukumaran, V.; Ezhilmaran, D.
2017-11-01
An authentication protocolis the type of computer communication protocol or cryptography protocol specifically designed for transfer of authentication data between two entities. We have planned a two new entity authentication scheme on the basis of root extraction problem near-ring in this article. We suggest that this problem is suitably difficult to serve as a cryptographic assumption over the platform of near-ring N. The security issues also discussed.
Finite element solution of optimal control problems with state-control inequality constraints
NASA Technical Reports Server (NTRS)
Bless, Robert R.; Hodges, Dewey H.
1992-01-01
It is demonstrated that the weak Hamiltonian finite-element formulation is amenable to the solution of optimal control problems with inequality constraints which are functions of both state and control variables. Difficult problems can be treated on account of the ease with which algebraic equations can be generated before having to specify the problem. These equations yield very accurate solutions. Owing to the sparse structure of the resulting Jacobian, computer solutions can be obtained quickly when the sparsity is exploited.
Easy way to determine quantitative spatial resolution distribution for a general inverse problem
NASA Astrophysics Data System (ADS)
An, M.; Feng, M.
2013-12-01
The spatial resolution computation of a solution was nontrivial and more difficult than solving an inverse problem. Most geophysical studies, except for tomographic studies, almost uniformly neglect the calculation of a practical spatial resolution. In seismic tomography studies, a qualitative resolution length can be indicatively given via visual inspection of the restoration of a synthetic structure (e.g., checkerboard tests). An effective strategy for obtaining quantitative resolution length is to calculate Backus-Gilbert resolution kernels (also referred to as a resolution matrix) by matrix operation. However, not all resolution matrices can provide resolution length information, and the computation of resolution matrix is often a difficult problem for very large inverse problems. A new class of resolution matrices, called the statistical resolution matrices (An, 2012, GJI), can be directly determined via a simple one-parameter nonlinear inversion performed based on limited pairs of random synthetic models and their inverse solutions. The total procedure were restricted to forward/inversion processes used in the real inverse problem and were independent of the degree of inverse skill used in the solution inversion. Spatial resolution lengths can be directly given during the inversion. Tests on 1D/2D/3D model inversion demonstrated that this simple method can be at least valid for a general linear inverse problem.
Du, Yuanwei; Guo, Yubin
2015-01-01
The intrinsic mechanism of multimorbidity is difficult to recognize and prediction and diagnosis are difficult to carry out accordingly. Bayesian networks can help to diagnose multimorbidity in health care, but it is difficult to obtain the conditional probability table (CPT) because of the lack of clinically statistical data. Today, expert knowledge and experience are increasingly used in training Bayesian networks in order to help predict or diagnose diseases, but the CPT in Bayesian networks is usually irrational or ineffective for ignoring realistic constraints especially in multimorbidity. In order to solve these problems, an evidence reasoning (ER) approach is employed to extract and fuse inference data from experts using a belief distribution and recursive ER algorithm, based on which evidence reasoning method for constructing conditional probability tables in Bayesian network of multimorbidity is presented step by step. A multimorbidity numerical example is used to demonstrate the method and prove its feasibility and application. Bayesian network can be determined as long as the inference assessment is inferred by each expert according to his/her knowledge or experience. Our method is more effective than existing methods for extracting expert inference data accurately and is fused effectively for constructing CPTs in a Bayesian network of multimorbidity.
Gone with the Wind: Conceiving of Moral Responsibility in the Case of GMO Contamination.
Robaey, Zoë
2016-06-01
Genetically modified organisms are a technology now used with increasing frequency in agriculture. Genetically modified seeds have the special characteristic of being living artefacts that can reproduce and spread; thus it is difficult to control where they end up. In addition, genetically modified seeds may also bring about uncertainties for environmental and human health. Where they will go and what effect they will have is therefore very hard to predict: this creates a puzzle for regulators. In this paper, I use the problem of contamination to complicate my ascription of forward-looking moral responsibility to owners of genetically modified organisms. Indeed, how can owners act responsibly if they cannot know that contamination has occurred? Also, because contamination creates new and unintended ownership, it challenges the ascription of forward-looking moral responsibility based on ownership. From a broader perspective, the question this paper aims to answer is as follows: how can we ascribe forward-looking moral responsibility when the effects of the technologies in question are difficult to know or unknown? To solve this problem, I look at the epistemic conditions for moral responsibility and connect them to the normative notion of the social experiment. Indeed, examining conditions for morally responsible experimentation helps to define a range of actions and to establish the related epistemic virtues that owners should develop in order to act responsibly where genetically modified organisms are concerned.
Improving the quality of mass produced maps
Simley, J.
2001-01-01
Quality is critical in cartography because key decisions are often made based on the information the map communicates. The mass production of digital cartographic information to support geographic information science has now added a new dimension to the problem of cartographic quality, as problems once limited to small volumes can now proliferate in mass production programs. These problems can also affect the economics of map production by diverting a sizeable portion of production cost to pay for rework on maps with poor quality. Such problems are common to general industry-in response, the quality engineering profession has developed a number of successful methods to overcome these problems. Two important methods are the reduction of error through statistical analysis and addressing the quality environment in which people work. Once initial and obvious quality problems have been solved, outside influences periodically appear that cause adverse variations in quality and consequently increase production costs. Such errors can be difficult to detect before the customer is affected. However, a number of statistical techniques can be employed to detect variation so that the problem is eliminated before significant damage is caused. Additionally, the environment in which the workforce operates must be conductive to quality. Managers have a powerful responsibility to create this environment. Two sets of guidelines, known as Deming's Fourteen Points and ISO-9000, provide models for this environment.
García, Sandra G; Becker, Davida; de Castro, Marcela Martínez; Paz, Francisco; Olavarrieta, Claudia Díaz; Acevedo-García, Dolores
2008-09-01
Workers in Mexico's maquiladoras (assembly plants) are mainly young, single women, many of whom could benefit from emergency contraceptive pills (ECPs). Because ECPs are readily available in Mexico, women who know about the therapy can obtain it easily. Do maquiladora workers know about the method? Could worksite programs help increase awareness? To investigate these questions, we conducted a five-month intervention during which workers in three maquiladoras along the Mexico-United States border could attend educational talks on ECPs, receive pamphlets, and obtain kits containing EC supplies. Among the workers exposed to our intervention, knowledge of ECPs increased. Reported ECP use also increased. Although our intervention apparently increased workers' knowledge and use, the factory proved to be a difficult intervention setting. Problems we experienced included a factory closure and management/staff opposition to certain project elements. Future studies should continue to investigate work-site interventions and other strategies to reach workers.
Social Learning in the Schools Through Psychodrama.
ERIC Educational Resources Information Center
Allen, Doris Twitchell
Psychodrama is the acting out of difficult situations one has experienced. It gives the actors and spectators the chance to try out alternative solutions to problem situations. When these problems are acted out, the actors become better acquainted with themselves and their peers. This awareness becomes a dominant determinant of future behavior.…
Loci of Difficulty in Learning to Program. Technical Report 86-6.
ERIC Educational Resources Information Center
Perkins, David; And Others
To learn more about the specific nature of the teaching and learning problems involved, researchers conducted a clinical study of 20 high school students enrolled a BASIC course. Investigators presented each student with a sequence of eight programming problems, ranging from easy to difficult. They asked questions to track student thinking and…
Objective, Way and Method of Faculty Management Based on Ergonomics
ERIC Educational Resources Information Center
WANG, Hong-bin; Liu, Yu-hua
2008-01-01
The core problem that influences educational quality of talents in colleges and universities is the faculty management. Without advanced faculty, it is difficult to cultivate excellent talents. With regard to some problems in present faculty construction of colleges and universities, this paper puts forward the new objectives, ways and methods of…
ADHD: Misconceptions and the Four Rules of Treatment
ERIC Educational Resources Information Center
Kutscher, Martin L.
2008-01-01
Contrary to popular opinion, attention deficit hyperactivity disorder (ADHD) is not just about hyperactive people who have short attention spans. ADHD is a disorder that involves difficult problems on a wide range of "executive dysfunction," a wide range of co-occuring conditions, and family problems. People need to recognize that ADHD is not just…
Some Legal Problems of Satellite Transmission.
ERIC Educational Resources Information Center
Siebert, Fred S.
Now that the technical aspects of satellite transmission have been solved, there remain the more complex and difficult problems of maintaining both order in outer space and the rights of nations and individuals as these rights may be affected by broadcasts transmitted by satellite stations. These broadcasts, whether beamed to a ground station or…
A Solution to the Mysteries of Morality
ERIC Educational Resources Information Center
DeScioli, Peter; Kurzban, Robert
2013-01-01
We propose that moral condemnation functions to guide bystanders to choose the same side as other bystanders in disputes. Humans interact in dense social networks, and this poses a problem for bystanders when conflicts arise: which side, if any, to support. Choosing sides is a difficult strategic problem because the outcome of a conflict…
Teaching Economics to the Best Undergraduates: What Are the Problems?
ERIC Educational Resources Information Center
Andreopoulos, Giuliana Campanelli; Panayides, Alexandros
2009-01-01
Economics is usually perceived as a difficult subject among undergraduate students with negative repercussions on their performance. The literature suggests that the students' problems with principles of economics are mainly related to the style and method of teaching together with the course content. Particularly attacked are the chalk and talk…
A Problem in Online Interpersonal Skills Training: Do Learners Practice Skills?
ERIC Educational Resources Information Center
Doo, Min Young
2006-01-01
One problem found when teaching interpersonal skills online is learners' lack of opportunity for skill practice. The online learning environment is deficient in face-to-face interaction, and opportunities for self-regulation make it difficult to ensure learners practice skills despite the positive effects of such practice on skill improvement. The…
ERIC Educational Resources Information Center
Guberman, Raisa; Leikin, Roza
2013-01-01
The study considers mathematical problem solving to be at the heart of mathematics teaching and learning, while mathematical challenge is a core element of any educational process. The study design addresses the complexity of teachers' knowledge. It is aimed at exploring the development of teachers' mathematical and pedagogical conceptions…
Using Syntactic Patterns to Enhance Text Analytics
ERIC Educational Resources Information Center
Meyer, Bradley B.
2017-01-01
Large scale product and service reviews proliferate and are commonly found across the web. The ability to harvest, digest and analyze a large corpus of reviews from online websites is still however a difficult problem. This problem is referred to as "opinion mining." Opinion mining is an important area of research as advances in the…
ERIC Educational Resources Information Center
Tzohar-Rozen, Meirav; Kramarski, Bracha
2017-01-01
Mathematical problem solving is one of the most valuable aspects of mathematics education and the most difficult for elementary school students. Cognitive and metacognitive difficulties in this area cause students to develop negative attitudes and emotions as affective reactions, hampering their efforts and achievements. These metacognitive and…
ERIC Educational Resources Information Center
Tzohar-Rozen, Meirav; Kramarski, Bracha
2014-01-01
Mathematical problem solving is one of the most valuable aspects of mathematics education. It is also the most difficult for elementary-school students (Verschaffel, Greer, & De Corte, 2000). Students experience cognitive and metacognitive difficulties in this area and develop negative emotions and poor motivation, which hamper their efforts…
The Effect of Shift-Problem Lessons in the Mathematics Classroom
ERIC Educational Resources Information Center
Palha, Sonia; Dekker, Rijkje; Gravemeijer, Koeno
2015-01-01
It remains difficult to foster problem-solving and mathematical-reasoning capabilities in classrooms where students and teachers are accustomed to the more traditional forms of education. Several studies suggest that this difficulty might be related to the kind of knowledge students acquire in such environments, which could be fragmented and…
Small Village Planning Problems in the Netherlands.
ERIC Educational Resources Information Center
Groot, Jacob P.
The problems associated with small villages are among the most difficult in Dutch physical planning, for they encompass the support of minimum social services in small towns and villages; the preservation of areas of ecological and scenic value; the acommodation of a growing population desirous of a home in the country or continued country living;…
How Can "Problem Subjects" Be Made Less of a Problem?
ERIC Educational Resources Information Center
Warwick, Philip; Ottewill, Roger
2004-01-01
Many higher education courses, across the whole range of disciplines, include subjects that are somewhat problematic because they appear to be unrelated to other components of the curriculum. Students frequently perceive them as irrelevant and boring. This makes it extremely difficult for lecturers to stimulate interest and results in an…
Student Homicidal Violence in Schools: An International Problem
ERIC Educational Resources Information Center
Bondu, Rebecca; Cornell, Dewey G.; Scheithauer, Herbert
2011-01-01
School homicides have become a worldwide phenomenon. In the decade following the Columbine shooting there have been at least forty similar events in other countries. This article addresses the international scope of this problem and some of the complex conceptual issues that make student homicidal violence difficult to define and study. Meaningful…
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…
Some Considerations in Maintaining Adaptive Test Item Pools.
ERIC Educational Resources Information Center
Stocking, Martha L.
The construction of parallel editions of conventional tests for purposes of test security while maintaining score comparability has always been a recognized and difficult problem in psychometrics and test construction. The introduction of new modes of test construction, e.g., adaptive testing, changes the nature of the problem, but does not make…
Deafness and autistic spectrum disorders.
Vernon, McCay; Rhodes, Anthony
2009-01-01
An orientation to autistic spectrum disorders (ASD), also known as autism, is provided, and the specific syndrome of autism and deafness is addressed. The two conditions have in common a major problem: communication. Case histories are provided, the development of treatment for autism is discussed, and the separate disorders that make up ASD are defined. Important medical conditions often present in ASD are named, and their roles in treatment and diagnosis are described. Because autism is generally regarded as increasing in prevalence, some say to epidemic proportions, there is an increase in children who are both deaf and autistic. The resulting pressure on day and residential school programs for the Deaf to accept and educate these difficult, multiply disabled children is increasing. The parents of autistic children are a sophisticated, politically active group who are demanding services through legal and legislative means, among others.
Kohro, Takahide; Furui, Yuji; Mitsutake, Naohiro; Fujii, Ryo; Morita, Hiroyuki; Oku, Shinya; Ohe, Kazuhiko; Nagai, Ryozo
2008-03-01
Similar to the healthcare systems in other industrialized countries, the Japanese healthcare system is facing the problem of increasing medical expenditure. In Japan, this situation may be primarily attributed to advanced technological developments, an aging population, and increasing patient demand. Japan also faces the problem of a declining youth population due to a low birth rate. Taken together, these problems present the healthcare system with a very difficult financial situation. Several reforms have been undertaken to contain medical expenditure, such as increasing employee copayment for health insurance from 10% to 20% in 1997 and from 20% to 30% in 2003 in order to curb unnecessary visits to medical institutions. Since the aging of the Japanese population is inevitable, a suitable method to contain medical expenditure may be to screen individuals who are likely to develop lifestyle-related diseases and conduct early intervention programs for them to prevent the development of diseases such as myocardial infarction or stroke that are costly to treat. If this goal is attained, it may contribute to the containment of medical expenditure as well as to improving the quality of life of the elderly. Therefore, the Japanese Ministry of Health, Labor and Welfare has decided to introduce a nationwide health screening and intervention program specifically targeting the metabolic syndrome commencing April 2008. Here, we discuss (1) the background of the Japanese healthcare system and the problems facing it, (2) the underlying objective and details of the new screening program, and (3) the expected impact of the program.
Explicit solution techniques for impact with contact constraints
NASA Technical Reports Server (NTRS)
Mccarty, Robert E.
1993-01-01
Modern military aircraft transparency systems, windshields and canopies, are complex systems which must meet a large and rapidly growing number of requirements. Many of these transparency system requirements are conflicting, presenting difficult balances which must be achieved. One example of a challenging requirements balance or trade is shaping for stealth versus aircrew vision. The large number of requirements involved may be grouped in a variety of areas including man-machine interface; structural integration with the airframe; combat hazards; environmental exposures; and supportability. Some individual requirements by themselves pose very difficult, severely nonlinear analysis problems. One such complex problem is that associated with the dynamic structural response resulting from high energy bird impact. An improved analytical capability for soft-body impact simulation was developed.
Explicit solution techniques for impact with contact constraints
NASA Astrophysics Data System (ADS)
McCarty, Robert E.
1993-08-01
Modern military aircraft transparency systems, windshields and canopies, are complex systems which must meet a large and rapidly growing number of requirements. Many of these transparency system requirements are conflicting, presenting difficult balances which must be achieved. One example of a challenging requirements balance or trade is shaping for stealth versus aircrew vision. The large number of requirements involved may be grouped in a variety of areas including man-machine interface; structural integration with the airframe; combat hazards; environmental exposures; and supportability. Some individual requirements by themselves pose very difficult, severely nonlinear analysis problems. One such complex problem is that associated with the dynamic structural response resulting from high energy bird impact. An improved analytical capability for soft-body impact simulation was developed.
Smith, Steven R
2012-09-01
The insanity defense presents many difficult questions for the legal system. It attracts attention beyond its practical significance (it is seldom used successfully) because it goes to the heart of the concept of legal responsibility. "Not guilty by reason of insanity" generally requires that as a result of mental illness the defendant was unable to distinguish right from wrong at the time of the crime. The many difficult and complex questions presented by the insanity defense have led some in the legal community to hope that neuroscience might help resolve some of these problems, but that hope is not likely to be realized.
Quantum Heterogeneous Computing for Satellite Positioning Optimization
NASA Astrophysics Data System (ADS)
Bass, G.; Kumar, V.; Dulny, J., III
2016-12-01
Hard optimization problems occur in many fields of academic study and practical situations. We present results in which quantum heterogeneous computing is used to solve a real-world optimization problem: satellite positioning. Optimization problems like this can scale very rapidly with problem size, and become unsolvable with traditional brute-force methods. Typically, such problems have been approximately solved with heuristic approaches; however, these methods can take a long time to calculate and are not guaranteed to find optimal solutions. Quantum computing offers the possibility of producing significant speed-up and improved solution quality. There are now commercially available quantum annealing (QA) devices that are designed to solve difficult optimization problems. These devices have 1000+ quantum bits, but they have significant hardware size and connectivity limitations. We present a novel heterogeneous computing stack that combines QA and classical machine learning and allows the use of QA on problems larger than the quantum hardware could solve in isolation. We begin by analyzing the satellite positioning problem with a heuristic solver, the genetic algorithm. The classical computer's comparatively large available memory can explore the full problem space and converge to a solution relatively close to the true optimum. The QA device can then evolve directly to the optimal solution within this more limited space. Preliminary experiments, using the Quantum Monte Carlo (QMC) algorithm to simulate QA hardware, have produced promising results. Working with problem instances with known global minima, we find a solution within 8% in a matter of seconds, and within 5% in a few minutes. Future studies include replacing QMC with commercially available quantum hardware and exploring more problem sets and model parameters. Our results have important implications for how heterogeneous quantum computing can be used to solve difficult optimization problems in any field.
Wang, Yiji; Dix, Theodore
2017-03-01
This study examined processes that might account for why negatively emotional children are at high risk for externalizing behavior problems when raised by mothers with depressive symptoms. Because negative emotionality regulates adaptation to stress, we predicted that it would undermine children's adjustment to mothers' depressive symptoms by increasing child emotions likely to elicit reciprocal negativity from depressed mothers, bias negatively children's attributions about others, and activate difficult-to-control oppositional responses. In a large sample (N = 1,082) evaluated from 6 months to second grade, results showed that, when mothers had depressive symptoms early in the child's development, children who were high in negative emotionality-but not those who were low-displayed increased risk for externalizing problems in second grade. This risk reflected tendencies for negatively emotional children, when raised by mothers with depressive symptoms, to develop hostile attributions about others and poor self-regulation of the negativity these attributions promote. The findings suggest that, when mothers with depressive symptoms raise negatively emotional children, children's risk for externalizing behavior problems may reflect tendencies for high negative emotion in children and reciprocal negativity in the dyad to undermine the development of attributional and self-regulatory processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Teaching basic science to optimize transfer.
Norman, Geoff
2009-09-01
Basic science teachers share the concern that much of what they teach is soon forgotten. Although some evidence suggests that relatively little basic science is forgotten, it may not appear so, as students commonly have difficulty using these concepts to solve or explain clinical problems: This phenomenon, using a concept learned in one context to solve a problem in a different context, is known to cognitive psychologists as transfer. The psychology literature shows that transfer is difficult; typically, even though students may know a concept, fewer than 30% will be able to use it to solve new problems. However a number of strategies to improve transfer can be adopted at the time of initial teaching of the concept, in the use of exemplars to illustrate the concept, and in practice with additional problems. In this article, we review the literature in psychology to identify practical strategies to improve transfer. Critical review of psychology literature to identify factors that enhance or impede transfer. There are a number of strategies available to teachers to facilitate transfer. These include active problem-solving at the time of initial learning, imbedding the concept in a problem context, using everyday analogies, and critically, practice with multiple dissimilar problems. Further, mixed practice, where problems illustrating different concepts are mixed together, and distributed practice, spread out over time, can result in significant and large gains. Transfer is difficult, but specific teaching strategies can enhance this skill by factors of two or three.
An Architectural Model of Visual Motion Understanding
1989-08-01
of the Center for Visual Sciences of the University of Rochester. Their courage in the face of the overwhelming com- plexity of the human visual...analysis should perform better than either approach by itself. Notice that the problems of the two approaches are non-overlapping. Continuous methods face no...success. This is not terribly surprising, as the problem is inherently very difficult. Consider the problems faced by a unit that is trying to compute the
NASA Technical Reports Server (NTRS)
Cash, W.
1979-01-01
Many problems in the experimental estimation of parameters for models can be solved through use of the likelihood ratio test. Applications of the likelihood ratio, with particular attention to photon counting experiments, are discussed. The procedures presented solve a greater range of problems than those currently in use, yet are no more difficult to apply. The procedures are proved analytically, and examples from current problems in astronomy are discussed.
[Venous thromboembolism: an urgent call for action].
Páramo, José A; Lecumberri, Ramón
2009-10-17
Thousands of individuals suffer from deep vein thrombosis (DVT) all over the world, and many will die from its main complication, pulmonary embolism (PE). An important problem is that the diagnose is easy to overlook because the signs and symptoms are often difficult to recognize. Why do DVT and PE remain such a serious problem, particularly given the availability of effective strategies for preventing and treating them? The answer lays primarily in the failure to consistently use evidence-based interventions in high-risk individuals and in the lack of adherence to the different prophylactic interventions. In order to impact the incidence and burden of DVT/PE and increase public awareness, implementation of electronic alerts and evidence-based approaches, and scientific translational research are required. The commitment of all levels of governments as well as public and private institutions will be crucial to reduce the incidence of DVT, a leading cause of death.
Modeling and comparative study of linear and nonlinear controllers for rotary inverted pendulum
NASA Astrophysics Data System (ADS)
Lima, Byron; Cajo, Ricardo; Huilcapi, Víctor; Agila, Wilton
2017-01-01
The rotary inverted pendulum (RIP) is a problem difficult to control, several studies have been conducted where different control techniques have been applied. Literature reports that, although problem is nonlinear, classical PID controllers presents appropriate performances when applied to the system. In this paper, a comparative study of the performances of linear and nonlinear PID structures is carried out. The control algorithms are evaluated in the RIP system, using indices of performance and power consumption, which allow the categorization of control strategies according to their performance. This article also presents the modeling system, which has been estimated some of the parameters involved in the RIP system, using computer-aided design tools (CAD) and experimental methods or techniques proposed by several authors attended. The results indicate a better performance of the nonlinear controller with an increase in the robustness and faster response than the linear controller.
Engagement and Retention of Suicide Attempters in Clinical Research
Gibbons, Carly J.; Stirman, Shannon Wiltsey; Brown, Gregory K.; Beck, Aaron T.
2010-01-01
Background High attrition rates in longitudinal research can limit study generalizability, threaten internal validity, and decrease statistical power. Research has demonstrated that there can be significant differences between participants who complete a research study and those who drop out prematurely, and that treatment outcomes may be dependent on retention in a treatment protocol. Aims The current paper describes the challenges encountered when implementing a randomized controlled trial of cognitive therapy for the prevention of suicide attempts and the solutions developed to overcome these problems. Methods Problems unique to suicide attempters are discussed, and strategies successfully implemented to boost retention rates are provided. Results The methods implemented appeared to increase retention rates in the randomized controlled trial. Conclusions Many steps can be taken to work with this difficult population, and researchers are encouraged to be as involved and flexible with participants as possible. PMID:20418211
Weather forecasting expert system study
NASA Technical Reports Server (NTRS)
1985-01-01
Weather forecasting is critical to both the Space Transportation System (STS) ground operations and the launch/landing activities at NASA Kennedy Space Center (KSC). The current launch frequency places significant demands on the USAF weather forecasters at the Cape Canaveral Forecasting Facility (CCFF), who currently provide the weather forecasting for all STS operations. As launch frequency increases, KSC's weather forecasting problems will be great magnified. The single most important problem is the shortage of highly skilled forecasting personnel. The development of forecasting expertise is difficult and requires several years of experience. Frequent personnel changes within the forecasting staff jeopardize the accumulation and retention of experience-based weather forecasting expertise. The primary purpose of this project was to assess the feasibility of using Artificial Intelligence (AI) techniques to ameliorate this shortage of experts by capturing aria incorporating the forecasting knowledge of current expert forecasters into a Weather Forecasting Expert System (WFES) which would then be made available to less experienced duty forecasters.
NASA Astrophysics Data System (ADS)
Wilson, H. F.
2013-12-01
First-principles atomistic simulation is a vital tool for understanding the properties of materials at the high-pressure high-temperature conditions prevalent in giant planet interiors, but properties such as solubility and phase boundaries are dependent on entropy, a quantity not directly accessible in simulation. Determining entropic properties from atomistic simulations is a difficult problem typically requiring a time-consuming integration over molecular dynamics trajectories. Here I will describe recent advances in first-principles thermodynamic calculations which substantially increase the simplicity and efficiency of thermodynamic integration and make entropic properties more readily accessible. I will also describe the use of first-principles thermodynamic calculations for understanding problems including core solubility in gas giants and superionic phase changes in ice giants, as well as future prospects for combining first-principles thermodynamics with planetary-scale models to help us understand the origin and consequences of compositional inhomogeneity in giant planet interiors.
Experimental Replication of an Aeroengine Combustion Instability
NASA Technical Reports Server (NTRS)
Cohen, J. M.; Hibshman, J. R.; Proscia, W.; Rosfjord, T. J.; Wake, B. E.; McVey, J. B.; Lovett, J.; Ondas, M.; DeLaat, J.; Breisacher, K.
2000-01-01
Combustion instabilities in gas turbine engines are most frequently encountered during the late phases of engine development, at which point they are difficult and expensive to fix. The ability to replicate an engine-traceable combustion instability in a laboratory-scale experiment offers the opportunity to economically diagnose the problem (to determine the root cause), and to investigate solutions to the problem, such as active control. The development and validation of active combustion instability control requires that the causal dynamic processes be reproduced in experimental test facilities which can be used as a test bed for control system evaluation. This paper discusses the process through which a laboratory-scale experiment was designed to replicate an instability observed in a developmental engine. The scaling process used physically-based analyses to preserve the relevant geometric, acoustic and thermo-fluid features. The process increases the probability that results achieved in the single-nozzle experiment will be scalable to the engine.
Harmonisation of microbial sampling and testing methods for distillate fuels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hill, G.C.; Hill, E.C.
1995-05-01
Increased incidence of microbial infection in distillate fuels has led to a demand for organisations such as the Institute of Petroleum to propose standards for microbiological quality, based on numbers of viable microbial colony forming units. Variations in quality requirements, and in the spoilage significance of contaminating microbes plus a tendency for temporal and spatial changes in the distribution of microbes, makes such standards difficult to implement. The problem is compounded by a diversity in the procedures employed for sampling and testing for microbial contamination and in the interpretation of the data obtained. The following paper reviews these problems andmore » describes the efforts of The Institute of Petroleum Microbiology Fuels Group to address these issues and in particular to bring about harmonisation of sampling and testing methods. The benefits and drawbacks of available test methods, both laboratory based and on-site, are discussed.« less
Skin and psyche--from the surface to the depth of the inner world.
Beltraminelli, Helmut; Itin, Peter
2008-01-01
About 30% of dermatology patients have signs or symptoms of psychological problems. Dermatologists should be familiar with the basics needed to identify, advise and treat these patients. Because of the complex interaction between skin and psyche, it is difficult to distinguish whether the primary problem is the skin or the psyche. Sometimes the clinical picture is a consequence of interactions between them and other factors. The interactions between skin and psyche are well known in history, art and literature--perhaps better known today because the marked emphasis on such images in our modern multimedia society. Aging is increasingly perceived as an illness and not as a physiological process. Through globalization, many different cultural approaches to the skin have entered in our daily life and influence our communication. This article considers the most important dermatoses which often show primary or secondary interaction with the psyche.
Bio-inspired group modeling and analysis for intruder detection in mobile sensor/robotic networks.
Fu, Bo; Xiao, Yang; Liang, Xiannuan; Philip Chen, C L
2015-01-01
Although previous bio-inspired models have concentrated on invertebrates (such as ants), mammals such as primates with higher cognitive function are valuable for modeling the increasingly complex problems in engineering. Understanding primates' social and communication systems, and applying what is learned from them to engineering domains is likely to inspire solutions to a number of problems. This paper presents a novel bio-inspired approach to determine group size by researching and simulating primate society. Group size does matter for both primate society and digital entities. It is difficult to determine how to group mobile sensors/robots that patrol in a large area when many factors are considered such as patrol efficiency, wireless interference, coverage, inter/intragroup communications, etc. This paper presents a simulation-based theoretical study on patrolling strategies for robot groups with the comparison of large and small groups through simulations and theoretical results.
Improved Method for Prediction of Attainable Wing Leading-Edge Thrust
NASA Technical Reports Server (NTRS)
Carlson, Harry W.; McElroy, Marcus O.; Lessard, Wendy B.; McCullers, L. Arnold
1996-01-01
Prediction of the loss of wing leading-edge thrust and the accompanying increase in drag due to lift, when flow is not completely attached, presents a difficult but commonly encountered problem. A method (called the previous method) for the prediction of attainable leading-edge thrust and the resultant effect on airplane aerodynamic performance has been in use for more than a decade. Recently, the method has been revised to enhance its applicability to current airplane design and evaluation problems. The improved method (called the present method) provides for a greater range of airfoil shapes from very sharp to very blunt leading edges. It is also based on a wider range of Reynolds numbers than was available for the previous method. The present method, when employed in computer codes for aerodynamic analysis, generally results in improved correlation with experimental wing-body axial-force data and provides reasonable estimates of the measured drag.
Ohba, Seigo; Nakatani, Yuya; Kawasaki, Takako; Tajima, Nobutaka; Tobita, Takayoshi; Yoshida, Noriaki; Sawase, Takashi; Asahina, Izumi
2015-08-01
Increasing numbers of older patients are seeking orthognathic surgery to treat jaw deformity. However, orthodontic and orthognathic surgical treatment is difficult in cases without occlusal vertical stop. A 55-year-old man presented with Class III malocclusion and mandibular protrusion including esthetic problems and posterior bite collapse. He underwent dental implant treatment to reconstruct an occlusal vertical stop before orthognathic surgery. His occlusal function and esthetic problems improved after surgery, and his skeletal and occlusal stability has been maintained for 6 years. Dental implant placement at appropriate positions could help to determine the position of the proximal segment at orthognathic surgery and could shorten the time required to restore esthetic and occlusal function. This case demonstrates how skeletal and dental stability can be maintained long after surgery in a patient with jaw deformity and posterior bite collapse.
Chen, Xianling; Chen, Buyuan; Li, Xiaofan; Song, Qingxiao; Chen, Yuanzhong
2017-03-04
Hematology is difficult for students to learn. A beneficial education method for hematology clerkship training is required to help students develop clinical skills. Foreign medical students often encounter communication issues in China. To address this issue, Chinese post-graduates from our institute are willing to assist with educating foreign students. Therefore, we propose a mixed team-based learning method (MTBL) which might overcome communication problems in hematology clerkship. Twenty-two foreign medical Students attended a 2-week hematology clerkship in Fujian Medical University Union Hospital. Twenty-one foreign African medical students were assigned randomly into two groups. Fourteen foreign African medical students were assigned to MTBL group. Each MTBL team included two foreign African medical students and one Chinese post-graduate. Seven foreign African medical students were assigned to lecture-based learning method (LBL) group, which had a foreign medical classmate from Hong Kong or Chinese intern volunteers to serve as translators. The practice test scores of MTBL were significantly higher than LBL group (p < 0.05). The MTBL group had increased motivation to prepare before class, an engaged classroom atmosphere, and an improvement in their understanding of difficult topics. Interestingly, the Chinese post-graduates also benefited from this setting, as they found that this interaction improved their communication in the English language. The mixed team-based learning method overcomes communication problems in hematology clerkship. Foreign medical students and Chinese post-graduates alike can benefit from MTBL. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(2):93-96, 2017. © 2016 The International Union of Biochemistry and Molecular Biology.
Sterilization of instruments in solar ovens.
Jørgensen, A F; Nøhr, K; Boisen, F; Nøhr, J
2002-01-01
The sterilization of instruments in rural health clinics in less developed countries is an increasing problem as chemical methods can no longer be recommended and fuel wood is becoming increasingly scarce. It seems obvious, therefore, to utilize solar energy for sterilization purposes. A solar oven was designed and manufactured using local materials and simple tools. It was tested by physical, chemical and microbiological methods and, after successful testing, installed in a rural clinic. The oven was able to generate temperatures above 180 degrees C. On days with direct sunlight the oven fulfilled the international recommendations for hot air sterilization. The chemical indicators, Browne's tubes type 3 and 5, also changed colour. It was difficult to reach the right value for the sterilization effect during months with a low sun position. A moveable oven, or two ovens, must be installed to solve this problem. The solar oven has proven to be a realistic method for the sterilization of instruments. The solar oven is easy to make and use. It saves fuel and can be used in most tropical areas.
Living on the edge: health care expenses strain family budgets.
Cummingham, Peter J; Miller, Carolyn; Cassil, Alwyn
2008-12-01
Affordability of medical care is a central focus of health care reform efforts. As health care costs continue to increase and the economy declines sharply, there is very little cushion in family budgets for health care costs, even for families with insurance coverage. Financial pressures on families from medical bills increase sharply when out-of-pocket spending for health care services exceeds 2.5 percent of family income, according to a new national study by the Center for Studying Health System Change (HSC). Low-income families and people in poor health experience financial pressures at even lower levels of spending, largely because they have already accumulated large medical debts they are unable to pay off. Many Californians also incur substantial burdens from health care expenses, although the rate of medical bill problems is somewhat lower in California compared with the overall United States. Extended interviews with a select number of families facing problems with medical bills provide additional detail on how families are forced to make difficult trade-offs with other family necessities, put off paying other bills, cut down on other expenses and delay getting needed medical care
A Routing Protocol for Multisink Wireless Sensor Networks in Underground Coalmine Tunnels
Xia, Xu; Chen, Zhigang; Liu, Hui; Wang, Huihui; Zeng, Feng
2016-01-01
Traditional underground coalmine monitoring systems are mainly based on the use of wired transmission. However, when cables are damaged during an accident, it is difficult to obtain relevant data on environmental parameters and the emergency situation underground. To address this problem, the use of wireless sensor networks (WSNs) has been proposed. However, the shape of coalmine tunnels is not conducive to the deployment of WSNs as they are long and narrow. Therefore, issues with the network arise, such as extremely large energy consumption, very weak connectivity, long time delays, and a short lifetime. To solve these problems, in this study, a new routing protocol algorithm for multisink WSNs based on transmission power control is proposed. First, a transmission power control algorithm is used to negotiate the optimal communication radius and transmission power of each sink. Second, the non-uniform clustering idea is adopted to optimize the cluster head selection. Simulation results are subsequently compared to the Centroid of the Nodes in a Partition (CNP) strategy and show that the new algorithm delivers a good performance: power efficiency is increased by approximately 70%, connectivity is increased by approximately 15%, the cluster interference is diminished by approximately 50%, the network lifetime is increased by approximately 6%, and the delay is reduced with an increase in the number of sinks. PMID:27916917
A Routing Protocol for Multisink Wireless Sensor Networks in Underground Coalmine Tunnels.
Xia, Xu; Chen, Zhigang; Liu, Hui; Wang, Huihui; Zeng, Feng
2016-11-30
Traditional underground coalmine monitoring systems are mainly based on the use of wired transmission. However, when cables are damaged during an accident, it is difficult to obtain relevant data on environmental parameters and the emergency situation underground. To address this problem, the use of wireless sensor networks (WSNs) has been proposed. However, the shape of coalmine tunnels is not conducive to the deployment of WSNs as they are long and narrow. Therefore, issues with the network arise, such as extremely large energy consumption, very weak connectivity, long time delays, and a short lifetime. To solve these problems, in this study, a new routing protocol algorithm for multisink WSNs based on transmission power control is proposed. First, a transmission power control algorithm is used to negotiate the optimal communication radius and transmission power of each sink. Second, the non-uniform clustering idea is adopted to optimize the cluster head selection. Simulation results are subsequently compared to the Centroid of the Nodes in a Partition (CNP) strategy and show that the new algorithm delivers a good performance: power efficiency is increased by approximately 70%, connectivity is increased by approximately 15%, the cluster interference is diminished by approximately 50%, the network lifetime is increased by approximately 6%, and the delay is reduced with an increase in the number of sinks.
Customer and household matching: resolving entity identity in data warehouses
NASA Astrophysics Data System (ADS)
Berndt, Donald J.; Satterfield, Ronald K.
2000-04-01
The data preparation and cleansing tasks necessary to ensure high quality data are among the most difficult challenges faced in data warehousing and data mining projects. The extraction of source data, transformation into new forms, and loading into a data warehouse environment are all time consuming tasks that can be supported by methodologies and tools. This paper focuses on the problem of record linkage or entity matching, tasks that can be very important in providing high quality data. Merging two or more large databases into a single integrated system is a difficult problem in many industries, especially in the wake of acquisitions. For example, managing customer lists can be challenging when duplicate entries, data entry problems, and changing information conspire to make data quality an elusive target. Common tasks with regard to customer lists include customer matching to reduce duplicate entries and household matching to group customers. These often O(n2) problems can consume significant resources, both in computing infrastructure and human oversight, and the goal of high accuracy in the final integrated database can be difficult to assure. This paper distinguishes between attribute corruption and entity corruption, discussing the various impacts on quality. A metajoin operator is proposed and used to organize past and current entity matching techniques. Finally, a logistic regression approach to implementing the metajoin operator is discussed and illustrated with an example. The metajoin can be used to determine whether two records match, don't match, or require further evaluation by human experts. Properly implemented, the metajoin operator could allow the integration of individual databases with greater accuracy and lower cost.
Teaching medical professionals and trainees about adolescent suicide prevention: five key problems.
Sher, Leo
2012-01-01
Predicting and preventing suicide represent very difficult challenges for clinicians. The awareness of adolescent suicide as a major social and medical problem has increased over the past years. However, many health care professionals who have frequent contact with adolescents are not sufficiently trained in suicide evaluation techniques and approaches to adolescents with suicidal behavior. Suicide prevention efforts among adolescents are restricted by the fact that there are five key problems related to the evaluation and management of suicidality in adolescents: 1. Many clinicians underestimate the importance of the problem of adolescent suicidal behavior and underestimate its prevalence. 2. There is a misconception that direct questioning of adolescents about suicidality is sufficient to evaluate suicide risk. 3. Another misconception is that adolescents with non-psychiatric illnesses do not need to be evaluated for suicidality. 4. Many clinicians do not know about or underestimate the role of contagion in adolescent suicidal behavior. 5. There is a mistaken belief that adolescent males are at lower suicide risk than adolescent females. Educating medical professionals and trainees about the warning signs and symptoms of adolescent suicide and providing them with tools to recognize, evaluate, and manage suicidal patients represent a promising approach to adolescent suicide prevention.
NASA Astrophysics Data System (ADS)
Auger-Méthé, Marie; Field, Chris; Albertsen, Christoffer M.; Derocher, Andrew E.; Lewis, Mark A.; Jonsen, Ian D.; Mills Flemming, Joanna
2016-05-01
State-space models (SSMs) are increasingly used in ecology to model time-series such as animal movement paths and population dynamics. This type of hierarchical model is often structured to account for two levels of variability: biological stochasticity and measurement error. SSMs are flexible. They can model linear and nonlinear processes using a variety of statistical distributions. Recent ecological SSMs are often complex, with a large number of parameters to estimate. Through a simulation study, we show that even simple linear Gaussian SSMs can suffer from parameter- and state-estimation problems. We demonstrate that these problems occur primarily when measurement error is larger than biological stochasticity, the condition that often drives ecologists to use SSMs. Using an animal movement example, we show how these estimation problems can affect ecological inference. Biased parameter estimates of a SSM describing the movement of polar bears (Ursus maritimus) result in overestimating their energy expenditure. We suggest potential solutions, but show that it often remains difficult to estimate parameters. While SSMs are powerful tools, they can give misleading results and we urge ecologists to assess whether the parameters can be estimated accurately before drawing ecological conclusions from their results.
Exploring the quantum speed limit with computer games
NASA Astrophysics Data System (ADS)
Sørensen, Jens Jakob W. H.; Pedersen, Mads Kock; Munch, Michael; Haikka, Pinja; Jensen, Jesper Halkjær; Planke, Tilo; Andreasen, Morten Ginnerup; Gajdacz, Miroslav; Mølmer, Klaus; Lieberoth, Andreas; Sherson, Jacob F.
2016-04-01
Humans routinely solve problems of immense computational complexity by intuitively forming simple, low-dimensional heuristic strategies. Citizen science (or crowd sourcing) is a way of exploiting this ability by presenting scientific research problems to non-experts. ‘Gamification’—the application of game elements in a non-game context—is an effective tool with which to enable citizen scientists to provide solutions to research problems. The citizen science games Foldit, EteRNA and EyeWire have been used successfully to study protein and RNA folding and neuron mapping, but so far gamification has not been applied to problems in quantum physics. Here we report on Quantum Moves, an online platform gamifying optimization problems in quantum physics. We show that human players are able to find solutions to difficult problems associated with the task of quantum computing. Players succeed where purely numerical optimization fails, and analyses of their solutions provide insights into the problem of optimization of a more profound and general nature. Using player strategies, we have thus developed a few-parameter heuristic optimization method that efficiently outperforms the most prominent established numerical methods. The numerical complexity associated with time-optimal solutions increases for shorter process durations. To understand this better, we produced a low-dimensional rendering of the optimization landscape. This rendering reveals why traditional optimization methods fail near the quantum speed limit (that is, the shortest process duration with perfect fidelity). Combined analyses of optimization landscapes and heuristic solution strategies may benefit wider classes of optimization problems in quantum physics and beyond.
Exploring the quantum speed limit with computer games.
Sørensen, Jens Jakob W H; Pedersen, Mads Kock; Munch, Michael; Haikka, Pinja; Jensen, Jesper Halkjær; Planke, Tilo; Andreasen, Morten Ginnerup; Gajdacz, Miroslav; Mølmer, Klaus; Lieberoth, Andreas; Sherson, Jacob F
2016-04-14
Humans routinely solve problems of immense computational complexity by intuitively forming simple, low-dimensional heuristic strategies. Citizen science (or crowd sourcing) is a way of exploiting this ability by presenting scientific research problems to non-experts. 'Gamification'--the application of game elements in a non-game context--is an effective tool with which to enable citizen scientists to provide solutions to research problems. The citizen science games Foldit, EteRNA and EyeWire have been used successfully to study protein and RNA folding and neuron mapping, but so far gamification has not been applied to problems in quantum physics. Here we report on Quantum Moves, an online platform gamifying optimization problems in quantum physics. We show that human players are able to find solutions to difficult problems associated with the task of quantum computing. Players succeed where purely numerical optimization fails, and analyses of their solutions provide insights into the problem of optimization of a more profound and general nature. Using player strategies, we have thus developed a few-parameter heuristic optimization method that efficiently outperforms the most prominent established numerical methods. The numerical complexity associated with time-optimal solutions increases for shorter process durations. To understand this better, we produced a low-dimensional rendering of the optimization landscape. This rendering reveals why traditional optimization methods fail near the quantum speed limit (that is, the shortest process duration with perfect fidelity). Combined analyses of optimization landscapes and heuristic solution strategies may benefit wider classes of optimization problems in quantum physics and beyond.
Design of an Aircrew Scheduling Decision Aid for the 6916th Electronic Security Squadron.
1987-06-01
Security Classification) Design of an Aircrew Scheduling Decision Aid for the 6916th Electronic Security Squadron 12. PERSONAL AUTHOR(S) Thomas J. Kopf...Because of the great number of possible scheduling alternatives, it is difficult to find an optimal solution to-the scheduling problem. Additionally...changes to the original schedule make it even more difficult to find an optimal solution. The emergence of capable microcompu- ters, decision support
Hospital renovation projects: phased construction requires planning at its best.
Cox, J C
1986-01-01
Building a new hospital facility is a difficult task, but adding onto and renovating an existing structure while normal activity continues is even more difficult. Project planners, designers, contractors, and hospital managers must carefully program the joint effort of construction and hospital operation. Several factors in the construction process and potential problems for hospital operations are described to help hospital managers better anticipate difficulties before plans are finalized and construction commences.
NASA Astrophysics Data System (ADS)
Abu-Zaid, N. A. M.
2017-11-01
In many circumstances, it is difficult for humans to reach some areas, due to its topography, personal safety, or security regulations in the country. Governments and persons need to calculate those areas and classify the green parts for reclamation to benefit from it.To solve this problem, this research proposes to use a phantom air plane to capture a digital image for the targeted area, then use a segmentation algorithm to separate the green space and calculate it's area. It was necessary to deal with two problems. The first is the variable elevation at which an image was taken, which leads to a change in the physical area of each pixel. To overcome this problem a fourth degree polynomial was fit to some experimental data. The second problem was the existence of different unconnected pieces of green areas in a single image, but we might be interested only in one of them. To solve this problem, the probability of classifying the targeted area as green was increased, while the probability of other untargeted sections was decreased by the inclusion of parts of it as non-green. A practical law was also devised to measure the target area in the digital image for comparison purposes with practical measurements and the polynomial fit.
NASA Astrophysics Data System (ADS)
Wang, Chuantao (C. T.)
2005-08-01
In the past decade, sheet metal forming and die development has been transformed to a science-based and technology-driven engineering and manufacturing enterprise from a tryout-based craft. Stamping CAE, especially the sheet metal forming simulation, as one of the core components in digital die making and digital stamping, has played a key role in this historical transition. The stamping simulation technology and its industrial applications have greatly impacted automotive sheet metal product design, die developments, die construction and tryout, and production stamping. The stamping CAE community has successfully resolved the traditional formability problems such as splits and wrinkles. The evolution of the stamping CAE technology and business demands opens even greater opportunities and challenges to stamping CAE community in the areas of (1) continuously improving simulation accuracy, drastically reducing simulation time-in-system, and improving operationalability (friendliness), (2) resolving those historically difficult-to-resolve problems such as dimensional quality problems (springback and twist) and surface quality problems (distortion and skid/impact lines), (3) resolving total manufacturability problems in line die operations including blanking, draw/redraw, trim/piercing, and flanging, and (4) overcoming new problems in forming new sheet materials with new forming techniques. In this article, the author first provides an overview of the stamping CAE technology adventures and achievements, and industrial applications in the past decade. Then the author presents a summary of increasing manufacturability needs from the formability to total quality and total manufacturability of sheet metal stampings. Finally, the paper outlines the new needs and trends for continuous improvements and innovations to meet increasing challenges in line die formability and quality requirements in automotive stamping.
Practical Math Skills: Situations--Strategies--Solutions. Intermediate Level. Grades 4-5-6.
ERIC Educational Resources Information Center
Duncan, Jim
This material is a supplement to existing mathematics programs for young learners. The activities presented are based on assumptions about the young problem solver which are difficult to address in standard mathematics texts. In these pages it is assumed that each learner brings to the problem-solving effort a very personal experience base and a…
ERIC Educational Resources Information Center
Nikolas, Molly; Klump, Kelly L.; Burt, S. Alexandra
2013-01-01
Prior work has suggested that inter-parental conflict likely plays an etiological role in child behavior problems. However, family-level measurement of inter-parental conflict in most traditional child twin studies has made it difficult to tease apart the specific causal mechanisms underlying this association. The Children's Perception of…
ERIC Educational Resources Information Center
Mallavarapu, Aditi; Lyons, Leilah; Shelley, Tia; Minor, Emily; Slattery, Brian; Zellner, Moria
2015-01-01
Interactive learning environments can provide learners with opportunities to explore rich, real-world problem spaces, but the nature of these problem spaces can make assessing learner progress difficult. Such assessment can be useful for providing formative and summative feedback to the learners, to educators, and to the designers of the…
The 1980 Aircraft Safety and Operating Problems, part 1
NASA Technical Reports Server (NTRS)
Stickle, J. W. (Compiler)
1981-01-01
It is difficult to categorize aircraft operating problems, human factors and safety. Much of NASA's research involves all three and considers the important inter-relationships between man, the machine and the environment, whether the environment be man-made or natural. Topics covered in 20 papers include terminal-area operations; avionics and human factors; and the atmospheric environment.
Analysis of Learning Behavior in a Flipped Programing Classroom Adopting Problem-Solving Strategies
ERIC Educational Resources Information Center
Chiang, Tosti Hsu-Cheng
2017-01-01
Programing is difficult for beginners because they need to learn the new language of computers. Developing software, especially complex software, is bound to result in problems, frustration, and the need to think in new ways. Identifying the learning behavior behind programing by way of empirical studies can help beginners learn more easily. In…
Visual impacts in the urban-wildland interface
Arthur W. Magill; Rowan A. Rowntree; Robert O. Brush
1979-01-01
The urban-wildland interface is treated as a place where extremes meet--where it is difficult to maintain a visually appealing transition from country to city. Problems are identified in relation to stable cities, urbanizing areas, and developing resorts in the wildlands. The visual problems of urbanization are also discussed in relation to physical impacts such as...
New Results in Astrodynamics Using Genetic Algorithms
NASA Technical Reports Server (NTRS)
Coverstone-Carroll, V.; Hartmann, J. W.; Williams, S. N.; Mason, W. J.
1998-01-01
Generic algorithms have gained popularity as an effective procedure for obtaining solutions to traditionally difficult space mission optimization problems. In this paper, a brief survey of the use of genetic algorithms to solve astrodynamics problems is presented and is followed by new results obtained from applying a Pareto genetic algorithm to the optimization of low-thrust interplanetary spacecraft missions.
Creating Task-Centered Instruction for Web-Based Instruction: Obstacles and Solutions
ERIC Educational Resources Information Center
Gardner, Joel; Jeon, Tae
2010-01-01
Merrill proposes First Principles of Instruction, including a problem- or task-centered strategy for designing instruction. However, when the tasks or problems are ill-defined or complex, task-centered instruction can be difficult to design. We describe an online task-centered training at a land-grant university designed to train employees to use…
Children's Understanding of Death as the Cessation of Agency: A Test Using Sleep Versus Death
ERIC Educational Resources Information Center
Barrett, H.C.; Behne, T.
2005-01-01
An important problem faced by children is discriminating between entities capable of goal-directed action, i.e. intentional agents, and non-agents. In the case of discriminating between living and dead animals, including humans, this problem is particularly difficult, because of the large number of perceptual cues that living and dead animals…
ERIC Educational Resources Information Center
Poitras, Eric G.; Doleck, Tenzin; Lajoie, Susanne P.
2018-01-01
Ill-structured problems, by definition, have multiple paths to a solution and are multifaceted making automated assessment and feedback a difficult challenge. Diagnostic reasoning about medical cases meet the criteria of ill-structured problem solving since there are multiple solution paths. The goal of this study was to develop an adaptive…
Self-Explaining Steps in Problem-Solving Tasks to Improve Self-Regulation in Secondary Education
ERIC Educational Resources Information Center
Baars, Martine; Leopold, Claudia; Paas, Fred
2018-01-01
The ability to learn in a self-regulated way is important for adolescents' academic achievements. Monitoring one's own learning is a prerequisite skill for successful self-regulated learning. However, accurate monitoring has been found to be difficult for adolescents, especially for learning problem-solving tasks such as can be found in math and…
Remembering the Singing of Silenced Voices: Brundibár and Problems of Pedagogy
ERIC Educational Resources Information Center
Dobbs, Teryl L.
2013-01-01
In this essay I explore problems of pedagogy related to Hans Krása's "Brundibár" by drawing heavily upon the thinking of two divergent theoretical perspectives regarding Holocaust testimony as advanced by Giorgio Agamben (2002) and Shoshana Felman (1992). I theorize that lodged within a space of difficult knowledge coalesced through…
Factors Contributing to the Problem of Student Absenteeism in a Rural School
ERIC Educational Resources Information Center
Durborow, Angela
2017-01-01
Student attendance would seem to be a vital link in measuring student success in school. If students are not in school, they miss instruction from the teacher. Without instruction it seems incredibly difficult to complete the work needed to pass classes and be successful in school. The research explored the problem of practice of student…
A Bridge between Two Important Problems in Optics and Electrostatics
ERIC Educational Resources Information Center
Capelli, R.; Pozzi, G.
2008-01-01
It is shown how the same physically appealing method can be applied to find analytic solutions for two difficult and apparently unrelated problems in optics and electrostatics. They are: (i) the diffraction of a plane wave at a perfectly conducting thin half-plane and (ii) the electrostatic field associated with a parallel array of stripes held at…
ERIC Educational Resources Information Center
Rands, Sean A.
2011-01-01
The design of experimental ecological fieldwork is difficult to teach to classes, particularly when protocols for data collection are normally carefully controlled by the class organiser. Normally, reinforcement of the some problems of experimental design such as the avoidance of pseudoreplication and appropriate sampling techniques does not occur…
A Practical Study of Mathematics Education Using Gamification
ERIC Educational Resources Information Center
Sakai, Kyohei; Shiota, Shingo
2016-01-01
This paper explores the use of gamification in math lessons for children in order to highlight the relationship between math education and its application to society. In school education, there is an existing problem about how to relate concepts learned in math to everyday life. One of the reasons for this problem is that it is difficult for…
ERIC Educational Resources Information Center
Mesman, Judi; Stoel, Reinoud; Bakermans-Kranenburg, Marian J.; van IJzendoorn, Marinus H.; Juffer, Femmie; Koot, Hans M.; Alink, Lenneke R. A.
2009-01-01
Using an accelerated longitudinal design, the development of externalizing problems from age 2 to 5 years was investigated in relation to maternal psychopathology, maternal parenting, gender, child temperament, and the presence of siblings. The sample consisted of 150 children selected at age 2-3 years for having high levels of externalizing…
ERIC Educational Resources Information Center
Smith, Mike U.
Both teachers and students alike acknowledge that genetics and genetics problem-solving are extremely difficult to learn and to teach. Therefore, a number of recommendations for teaching college genetics are offered. Although few of these ideas have as yet been tested in controlled experiments, they are supported by research and experience and may…
"Growing" Education in Difficult Environments Promoting Problem Solving: A Case from Palestine
ERIC Educational Resources Information Center
Jabr, Dua
2009-01-01
This paper presents a collaborative educational experiment "The Death of the Dead Sea: A Problem Based Learning" that was applied in two governmental high schools in Ramallah, Palestine in the school year 2006-2007. The students' role was to raise awareness to the phenomenon of the saltiest lake that shrinks towards extinction. In spite…
A Step-by-Step Guide to Tier 2 Behavioral Progress Monitoring
ERIC Educational Resources Information Center
Bruhn, Allison L.; McDaniel, Sara C.; Rila, Ashley; Estrapala, Sara
2018-01-01
Students who are at risk for or show low-intensity behavioral problems may need targeted, Tier 2 interventions. Often, Tier 2 problem-solving teams are charged with monitoring student responsiveness to intervention. This process may be difficult for those who are not trained in data collection and analysis procedures. To aid practitioners in these…
Grammatical Gender in L2: A Production or a Real-Time Processing Problem?
ERIC Educational Resources Information Center
Gruter, Theres; Lew-Williams, Casey; Fernald, Anne
2012-01-01
Mastery of grammatical gender is difficult to achieve in a second language (L2). This study investigates whether persistent difficulty with grammatical gender often observed in the speech of otherwise highly proficient L2 learners is best characterized as a production-specific performance problem, or as difficulty with the retrieval of gender…
The Shape of a Sausage: A Challenging Problem in the Calculus of Variations
ERIC Educational Resources Information Center
Deakin, Michael A. B.
2010-01-01
Many familiar household objects (such as sausages) involve the maximization of a volume under geometric constraints. A flexible but inextensible membrane bounds a volume which is to be filled to capacity. In the case of the sausage, a full analytic solution is here provided. Other related but more difficult problems seem to demand approximate…
Multi-Cultural Literacy in the Composition Classroom: Report on a Pilot Project.
ERIC Educational Resources Information Center
Hoffman, Amy
At the root of the writing problems of most college students is a lack of critical thinking. Students find analyzing an article or essay, writing a review, or arguing persuasively difficult and unpleasant because they have little practice in identifying and evaluating assumptions and reasoning. One solution to this problem, developed by a college…
ERIC Educational Resources Information Center
Gonda, Rebecca L.; DeHart, Kyle; Ashman, Tia-Lynn; Legg, Alison Slinskey
2015-01-01
Achieving a deep understanding of the many topics covered in middle school biology classes is difficult for many students. One way to help students learn these topics is through scenario-based learning, which enhances students' performance. The scenario-based problem-solving module presented here, "The Strawberry Caper," not only…
Transforming a Business Statistics Course with Just-in-Time Teaching
ERIC Educational Resources Information Center
Bangs, Joann
2012-01-01
This paper describes changing the way a business statistics course is taught through the use of just-in-time teaching methods. Implementing this method allowed for more time in the class to be spent focused on problem solving, resulting in students being able to handle more difficult problems. Students' perceptions of the just-in-time assignments…
African Immigrant Families in the United States: Surviving the Sociocultural Tide
ERIC Educational Resources Information Center
Obiakor, Festus E.; Afolayan, Michael O.
2007-01-01
There exists a significant yet unique level and magnitude of problems that immigrants of African descent have to grapple with in their efforts to settle down into their new American lives. This fact makes the continuity of the natal culture very difficult. However, in spite of their many problems, African immigrants never lose touch with their…
Competences of Mathematical Modelling of High School Students
ERIC Educational Resources Information Center
Sekerak, Josef
2010-01-01
Thanks to technological progress the world becomes more and more complicated. People stand in front of new and difficult problems that need to be solved. These are problems, the solutions of which are not universal, and cannot be learned. Many solutions require specific data that cannot be learned, as new data is part of the ongoing generation of…
Assessment of Theory of Mind in Children with Communication Disorders: Role of Presentation Mode
ERIC Educational Resources Information Center
van Buijsen, Marit; Hendriks, Angelique; Ketelaars, Mieke; Verhoeven, Ludo
2011-01-01
Children with communication disorders have problems with both language and social interaction. The theory-of-mind hypothesis provides an explanation for these problems, and different tests have been developed to test this hypothesis. However, different modes of presentation are used in these tasks, which make the results difficult to compare. In…
The "Consumer Report" version of Earth Science Data Quality description
NASA Astrophysics Data System (ADS)
Vicente, G. A.
2014-12-01
The generation, delivery and access of Earth Observation (EO) data quality information is a difficult problem because it is not uniquely defined, user dependent, difficult to be quantified, handled differently by different teams and perceived differently by data providers and data users. Initiatives such as the International Organization for Standards (ISO) 19115 and 19157 are important steps forward but difficult to implement, too complex and out of reach for the majority of data producers and users. This is because most users only want a quick and intelligible way to compare data sets from different providers to find the ones that best fit their interest. Therefore we need to simplify the problem by focusing on a few relevant quality parameters and develop a common framework to deliver them. This work is intended to tap into the data producers and user's knowledge and expertise on data quality for the development and adoption of a "Consumer Report" version of a "Data Quality Matrix". The goal is to find the most efficient and friendly approach to displays a selected number of quality parameters rated to each product and to target group of users.
Intelligent automated control of life support systems using proportional representations.
Wu, Annie S; Garibay, Ivan I
2004-06-01
Effective automatic control of Advanced Life Support Systems (ALSS) is a crucial component of space exploration. An ALSS is a coupled dynamical system which can be extremely sensitive and difficult to predict. As a result, such systems can be difficult to control using deliberative and deterministic methods. We investigate the performance of two machine learning algorithms, a genetic algorithm (GA) and a stochastic hill-climber (SH), on the problem of learning how to control an ALSS, and compare the impact of two different types of problem representations on the performance of both algorithms. We perform experiments on three ALSS optimization problems using five strategies with multiple variations of a proportional representation for a total of 120 experiments. Results indicate that although a proportional representation can effectively boost GA performance, it does not necessarily have the same effect on other algorithms such as SH. Results also support previous conclusions that multivector control strategies are an effective method for control of coupled dynamical systems.
What is biomedical informatics?
Bernstam, Elmer V.; Smith, Jack W.; Johnson, Todd R.
2009-01-01
Biomedical informatics lacks a clear and theoretically grounded definition. Many proposed definitions focus on data, information, and knowledge, but do not provide an adequate definition of these terms. Leveraging insights from the philosophy of information, we define informatics as the science of information, where information is data plus meaning. Biomedical informatics is the science of information as applied to or studied in the context of biomedicine. Defining the object of study of informatics as data plus meaning clearly distinguishes the field from related fields, such as computer science, statistics and biomedicine, which have different objects of study. The emphasis on data plus meaning also suggests that biomedical informatics problems tend to be difficult when they deal with concepts that are hard to capture using formal, computational definitions. In other words, problems where meaning must be considered are more difficult than problems where manipulating data without regard for meaning is sufficient. Furthermore, the definition implies that informatics research, teaching, and service should focus on biomedical information as data plus meaning rather than only computer applications in biomedicine. PMID:19683067
Parenteral nutrition in patients with inborn errors of metabolism - a therapeutic problem.
Kaluzny, L; Szczepanik, M; Siwinska-Mrozek, Z; Borkowska-Klos, M; Cichy, W; Walkowiak, J
2014-06-01
Parenteral nutrition is now a standard part of supportive treatment in pediatric departments. We describe four cases in which parenteral nutrition was extremely difficult due to coincidence with inborn errors of metabolism. The first two cases was fatty acid beta-oxidation disorders associated with necrotizing enterocolitis and congenital heart disease. Thus, limitations of intravenous lipid intake made it difficult to maintain a good nutritional status. The third case was phenylketonuria associated with a facial region tumour (rhabdomyosarcoma), in which parenteral nutrition was complicated because of a high phenylalanine content in the amino acid formulas for parenteral nutrition. The fourth patient was a child with late-diagnosed tyrosinemia type 1, complicated with encephalopathy - during intensive care treatment the patient needed nutritional support, including parenteral nutrition - we observed amino acid formula problems similar to those in the phenylketonuria patient. Parenteral nutrition in children with inborn errors of metabolism is a rare, but very important therapeutic problem. Total parenteral nutrition formulas are not prepared for this group of diseases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Graf, Peter; Dykes, Katherine; Scott, George
The layout of turbines in a wind farm is already a challenging nonlinear, nonconvex, nonlinearly constrained continuous global optimization problem. Here we begin to address the next generation of wind farm optimization problems by adding the complexity that there is more than one turbine type to choose from. The optimization becomes a nonlinear constrained mixed integer problem, which is a very difficult class of problems to solve. Furthermore, this document briefly summarizes the algorithm and code we have developed, the code validation steps we have performed, and the initial results for multi-turbine type and placement optimization (TTP_OPT) we have run.
1992-07-01
don’t multiplez the host References wtres, then neither does E., ® El. By repeated application of Theorem 1, using a leveled [1] D. S. Greenberg and S. N...1900, David Hilbert proposed twenty-three problems covering all areas of mathematics that guided the field for decades. These problems served a driving...session was to propose several grand challenge problems, similar in spirit to those of Hilbert [W1: [A] problem should be difficult in order to entice us
Distributed Control with Collective Intelligence
NASA Technical Reports Server (NTRS)
Wolpert, David H.; Wheeler, Kevin R.; Tumer, Kagan
1998-01-01
We consider systems of interacting reinforcement learning (RL) algorithms that do not work at cross purposes , in that their collective behavior maximizes a global utility function. We call such systems COllective INtelligences (COINs). We present the theory of designing COINs. Then we present experiments validating that theory in the context of two distributed control problems: We show that COINs perform near-optimally in a difficult variant of Arthur's bar problem [Arthur] (and in particular avoid the tragedy of the commons for that problem), and we also illustrate optimal performance in the master-slave problem.
Innately Split Model for Job-shop Scheduling Problem
NASA Astrophysics Data System (ADS)
Ikeda, Kokolo; Kobayashi, Sigenobu
Job-shop Scheduling Problem (JSP) is one of the most difficult benchmark problems. GA approaches often fail searching the global optimum because of the deception UV-structure of JSPs. In this paper, we introduce a novel framework model of GA, Innately Split Model (ISM) which prevents UV-phenomenon, and discuss on its power particularly. Next we analyze the structure of JSPs with the help of the UV-structure hypothesys, and finally we show ISM's excellent performance on JSP.
NASA Technical Reports Server (NTRS)
Beer, R.
1982-01-01
Problems in the spectroscopy of the planet are discussed. Two major problems are focused on: the almost total domination of the spectrum by CO2 (including almost every conceivable isotropic combination) makes the search for other species difficult; and the knowledge that no wavelengths short of the the microwave penetrate through the Venus cloud decks, which means that UV, visible, and IR remote sensing can investigate only the middle and upper atmosphere. The problem of intense multiple scattering is also considered.
Pitzer, Martina; Jennen-Steinmetz, Christine; Esser, Guenter; Schmidt, Martin H; Laucht, Manfred
2011-01-01
A difficult or undercontrolled temperament, as well as harsh parental discipline or a lack of warmth, has long been regarded as risk factors for the development of externalizing problems. In addition, it has been suggested that children with difficult temperament are especially susceptible to rearing influences. We investigated the impact of early temperament and parenting and their interactions on externalizing behavior at school age. Participants were 148 boys and 160 girls from a prospective longitudinal study on a high-risk sample. At ages 3 months and 2 years, temperament was assessed by a highly structured parent interview and standardized behavioral observations. Maternal parenting was assessed by videotaped behavioral observation and a parent questionnaire. Externalizing problems at age 8 years were measured by the Child Behavior Checklist. Using hierarchical linear regression analyses, we found that externalizing problems were predicted by psychosocial adversity and poor self-control, whereas no main effect for restrictive parenting or maternal empathy was found. Fearful-inhibited boys were positively affected by empathic and sensitive parenting, whereas girls who were low in self-control and/or fearful developed less externalizing problems with restrictive parenting. Our results partly support the differential susceptibility hypothesis. In addition, they point toward gender-specific pathways in the development of externalizing problems. Copyright © 2011 Elsevier Inc. All rights reserved.
Missed cases of multiple forms of child abuse and neglect.
Koc, Feyza; Oral, Resmiye; Butteris, Regina
2014-01-01
Child abuse and neglect is a public health problem and usually associated with family dysfunction due to multiple psychosocial, individual, and environmental factors. The diagnosis of child abuse may be difficult and require a high index of suspicion on the part of the practitioners encountering the child and the family. System-related factors may also enable abuse or prevent the early recognition of abuse. Child abuse and neglect that goes undiagnosed may give rise to chronic abuse and increased morbidity-mortality. In this report, we present two siblings who missed early diagnosis and we emphasize the importance of systems issues to allow early recognition of child abuse and neglect.
Atmospheric corrosion of metals in industrial city environment
Kusmierek, Elzbieta; Chrzescijanska, Ewa
2015-01-01
Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust. PMID:26217736
Instructional computing in space physics moves ahead
NASA Astrophysics Data System (ADS)
Russell, C. T.; Omidi, N.
As the number of spacecraft stationed in the Earth's magnetosphere exponentiates and society becomes more technologically sophisticated and dependent on these spacebased resources, both the importance of space physics and the need to train people in this field will increase.Space physics is a very difficult subject for students to master. Both mechanical and electromagnetic forces are important. The treatment of problems can be very mathematical, and the scale sizes of phenomena are usually such that laboratory studies become impossible, and experimentation, when possible at all, must be carried out in deep space. Fortunately, computers have evolved to the point that they are able to greatly facilitate instruction in space physics.
Keyword Extraction from Multiple Words for Report Recommendations in Media Wiki
NASA Astrophysics Data System (ADS)
Elakiya, K.; Sahayadhas, Arun
2017-03-01
This paper addresses the problem of multiple words search, with the goal of using these multiple word search to retrieve, relevant wiki page which will be recommended to end user. However, the existing system provides a link to wiki page for only a single keyword only which is available in Wikipedia. Therefore it is difficult to get the correct result when search input has multiple keywords or a sentence. We have introduced a ‘FastStringSearch’ technique which will provide option for efficient search with multiple key words and which will increase the flexibility for the end user to get his expected content easily.
Current update on portable dental equipment.
Charlton, David G; Ehrlich, A D; Miniotis, Nicholas J
2007-02-01
The dental care needs of the elderly are increasing as their population grows. For some of the elderly (eg, the nonambulatory, homebound, institutionalized), accessing dental care is a problem because they are unable to visit a traditional dental clinic. In the past, dental care has been taken to the homebound or institutionalized elderly by dentists using portable dental equipment. However, the perception that such equipment is difficult or impossible to obtain has limited the availability of on-site care. The purpose of this article is to describe various types of portable dental equipment and their features so that dentists interested in providing care to this group of patients are aware of them.
Problem of Mistakes in Databases, Processing and Interpretation of Observations of the Sun. I.
NASA Astrophysics Data System (ADS)
Lozitska, N. I.
In databases of observations unnoticed mistakes and misprints could occur at any stage of observation, preparation and processing of databases. The current detection of errors is complicated by the fact that the works of observer, databases compiler and researcher were divided. Data acquisition from a spacecraft requires the greater amount of researchers than for ground-based observations. As a result, the probability of errors is increasing. Keeping track of the errors on each stage is very difficult, so we use of cross-comparison of data from different sources. We revealed some misprints in the typographic and digital results of sunspot group area measurements.
Huang, Donghong; Ren, Xiaohua; Hu, Jingxuan; Shi, Jingcheng; Xia, Da; Sun, Zhenqiu
2015-02-01
Our primary health care institution began to implement national essential medicine system in 2009. In past fi ve years, the goal of national essential medicine system has been initially achieved. For examples, medicine price is steadily reducing, the quality of medical services is improving and residents' satisfaction is substantial increasing every year. However, at the same time, we also found some urgent problems needed to be solved. For examples, the range of national essential medicine is limited, which is difficult to guarantee the quality of essential medication. In addition, how to compensate the primary health care institution is still a question.
Resistant or difficult-to-treat hypertension.
Calhoun, David A
2006-03-01
Resistant hypertension, defined as uncontrolled hypertension on three medications, is becoming an increasingly common problem. In most cases, blood pressure remains elevated because of persistently high systolic blood pressure levels. Common characteristics of patients with resistant hypertension include older age, obesity, excessive dietary salt ingestion, and presence of sleep apnea. The evaluation of patients with resistant hypertension is focused on identifying contributing and secondary causes of hypertension. Treatment should include both lifestyle changes (weight loss, exercise, dietary salt restriction) and the use of effective multidrug regimens, including a diuretic. Recent data indicate that aldosterone antagonists may be effective when added to existing antihypertensive regimens even in the absence of primary aldosteronism.
Malware distributed collection and pre-classification system using honeypot technology
NASA Astrophysics Data System (ADS)
Grégio, André R. A.; Oliveira, Isabela L.; Santos, Rafael D. C.; Cansian, Adriano M.; de Geus, Paulo L.
2009-04-01
Malware has become a major threat in the last years due to the ease of spread through the Internet. Malware detection has become difficult with the use of compression, polymorphic methods and techniques to detect and disable security software. Those and other obfuscation techniques pose a problem for detection and classification schemes that analyze malware behavior. In this paper we propose a distributed architecture to improve malware collection using different honeypot technologies to increase the variety of malware collected. We also present a daemon tool developed to grab malware distributed through spam and a pre-classification technique that uses antivirus technology to separate malware in generic classes.
Antimicrobial resistance problems in typhoid fever
NASA Astrophysics Data System (ADS)
Saragih, R. H.; Purba, G. C. F.
2018-03-01
Typhoid fever (enteric fever) remains a burden in developing countries and a major health problem in Southern and Southeastern Asia. Salmonella typhi (S. typhi), the causative agent of typhoid fever, is a gram-negative, motile, rod-shaped, facultative anaerobe and solely a human pathogen with no animal reservoir. Infection of S. typhi can cause fever, abdominal pain and many worsenonspecific symptoms, including gastrointestinal symptoms suchas nausea, vomiting, constipation, and diarrhea. Chloramphenicol, ampicillin,and cotrimoxazole were the first-recommended antibiotics in treating typhoid fever. In the last two decades though, these three traditional drugs started to show resistance and developed multidrug resistance (MDR) S. typhi strains. In many parts of the world, the changing modes ofpresentation and the development of MDR have made typhoid fever increasingly difficult to treat.The use of first-line antimicrobials had been recommended to be fluoroquinolone as a replacement. However, this wassoonfollowedbyreportsof isolates ofS. typhi showing resistancetofluoroquinolones as well. These antimicrobial resistance problems in typhoid fever have been an alarming situation ever since and need to be taken seriously or else typhoid fever will no longer be taken care completely by administering antibiotics.
Psychedelics not linked to mental health problems or suicidal behavior: a population study.
Johansen, Pål-Ørjan; Krebs, Teri Suzanne
2015-03-01
A recent large population study of 130,000 adults in the United States failed to find evidence for a link between psychedelic use (lysergic acid diethylamide, psilocybin or mescaline) and mental health problems. Using a new data set consisting of 135,095 randomly selected United States adults, including 19,299 psychedelic users, we examine the associations between psychedelic use and mental health. After adjusting for sociodemographics, other drug use and childhood depression, we found no significant associations between lifetime use of psychedelics and increased likelihood of past year serious psychological distress, mental health treatment, suicidal thoughts, suicidal plans and suicide attempt, depression and anxiety. We failed to find evidence that psychedelic use is an independent risk factor for mental health problems. Psychedelics are not known to harm the brain or other body organs or to cause addiction or compulsive use; serious adverse events involving psychedelics are extremely rare. Overall, it is difficult to see how prohibition of psychedelics can be justified as a public health measure. © The Author(s) 2015.
Solving fuzzy shortest path problem by genetic algorithm
NASA Astrophysics Data System (ADS)
Syarif, A.; Muludi, K.; Adrian, R.; Gen, M.
2018-03-01
Shortest Path Problem (SPP) is known as one of well-studied fields in the area Operations Research and Mathematical Optimization. It has been applied for many engineering and management designs. The objective is usually to determine path(s) in the network with minimum total cost or traveling time. In the past, the cost value for each arc was usually assigned or estimated as a deteministic value. For some specific real world applications, however, it is often difficult to determine the cost value properly. One way of handling such uncertainty in decision making is by introducing fuzzy approach. With this situation, it will become difficult to solve the problem optimally. This paper presents the investigations on the application of Genetic Algorithm (GA) to a new SPP model in which the cost values are represented as Triangular Fuzzy Number (TFN). We adopts the concept of ranking fuzzy numbers to determine how good the solutions. Here, by giving his/her degree value, the decision maker can determine the range of objective value. This would be very valuable for decision support system in the real world applications.Simulation experiments were carried out by modifying several test problems with 10-25 nodes. It is noted that the proposed approach is capable attaining a good solution with different degree of optimism for the tested problems.
Statistical challenges in a regulatory review of cardiovascular and CNS clinical trials.
Hung, H M James; Wang, Sue-Jane; Yang, Peiling; Jin, Kun; Lawrence, John; Kordzakhia, George; Massie, Tristan
2016-01-01
There are several challenging statistical problems identified in the regulatory review of large cardiovascular (CV) clinical outcome trials and central nervous system (CNS) trials. The problems can be common or distinct due to disease characteristics and the differences in trial design elements such as endpoints, trial duration, and trial size. In schizophrenia trials, heavy missing data is a big problem. In Alzheimer trials, the endpoints for assessing symptoms and the endpoints for assessing disease progression are essentially the same; it is difficult to construct a good trial design to evaluate a test drug for its ability to slow the disease progression. In CV trials, reliance on a composite endpoint with low event rate makes the trial size so large that it is infeasible to study multiple doses necessary to find the right dose for study patients. These are just a few typical problems. In the past decade, adaptive designs were increasingly used in these disease areas and some challenges occur with respect to that use. Based on our review experiences, group sequential designs (GSDs) have borne many successful stories in CV trials and are also increasingly used for developing treatments targeting CNS diseases. There is also a growing trend of using more advanced unblinded adaptive designs for producing efficacy evidence. Many statistical challenges with these kinds of adaptive designs have been identified through our experiences with the review of regulatory applications and are shared in this article.
Science of the science, drug discovery and artificial neural networks.
Patel, Jigneshkumar
2013-03-01
Drug discovery process many times encounters complex problems, which may be difficult to solve by human intelligence. Artificial Neural Networks (ANNs) are one of the Artificial Intelligence (AI) technologies used for solving such complex problems. ANNs are widely used for primary virtual screening of compounds, quantitative structure activity relationship studies, receptor modeling, formulation development, pharmacokinetics and in all other processes involving complex mathematical modeling. Despite having such advanced technologies and enough understanding of biological systems, drug discovery is still a lengthy, expensive, difficult and inefficient process with low rate of new successful therapeutic discovery. In this paper, author has discussed the drug discovery science and ANN from very basic angle, which may be helpful to understand the application of ANN for drug discovery to improve efficiency.
NASA Astrophysics Data System (ADS)
Roy, Ronald A.
2004-05-01
Robert Apfel believed in the creative application of acoustics technology to difficult problems in biomedical sensing. Much of his work in this area focused on material characterization, with the intention of effecting diagnosis. His early work in blood cell characterization employed acoustic levitation to measure the bulk mechanical properties of human red blood cells. This subsequently paved the way to the use of high-frequency acoustic scattering to yield the compressibility and density of individual blood cells. Technology developed in this later effort was then adapted to the very difficult problem of transient micro-cavitation detection, and the active cavitation detector (ACD) was born. This paper traces this line of work from its origins and, in the process, serves to celebrate Bob Apfel's peerless ingenuity and irrepressible creativity.
Evans-Lacko, Sara; Knapp, Martin; McCrone, Paul; Thornicroft, Graham; Mojtabai, Ramin
2013-01-01
A period of economic recession may be particularly difficult for people with mental health problems as they may be at higher risk of losing their jobs, and more competitive labour markets can also make it more difficult to find a new job. This study assesses unemployment rates among individuals with mental health problems before and during the current economic recession. Using individual and aggregate level data collected from 27 EU countries in the Eurobarometer surveys of 2006 and 2010, we examined changes in unemployment rates over this period among individuals with and without mental health problems. Following the onset of the recession, the gap in unemployment rates between individuals with and without mental health problems significantly widened (odds ratio: 1.12, 95% confidence interval: 1.03, 1.34). This disparity became even greater for males, and individuals with low levels of education. Individuals with mental health problems living in countries with higher levels of stigmatizing attitudes regarding dangerousness of people with mental illness were more vulnerable to unemployment in 2010, but not 2006. Greater agreement that people with mental health problems have themselves to blame, was associated with lower likelihood of unemployment for individuals with and without mental health problems. These findings study suggest that times of economic hardship may intensify social exclusion of people with mental health problems, especially males and individuals with lower education. Interventions to combat economic exclusion and to promote social participation of individuals with mental health problems are even more important during times of economic crisis, and these efforts should target support to the most vulnerable groups.
NASA Astrophysics Data System (ADS)
Azila Che Musa, Nor; Mahmud, Zamalia; Baharun, Norhayati
2017-09-01
One of the important skills that is required from any student who are learning statistics is knowing how to solve statistical problems correctly using appropriate statistical methods. This will enable them to arrive at a conclusion and make a significant contribution and decision for the society. In this study, a group of 22 students majoring in statistics at UiTM Shah Alam were given problems relating to topics on testing of hypothesis which require them to solve the problems using confidence interval, traditional and p-value approach. Hypothesis testing is one of the techniques used in solving real problems and it is listed as one of the difficult concepts for students to grasp. The objectives of this study is to explore students’ perceived and actual ability in solving statistical problems and to determine which item in statistical problem solving that students find difficult to grasp. Students’ perceived and actual ability were measured based on the instruments developed from the respective topics. Rasch measurement tools such as Wright map and item measures for fit statistics were used to accomplish the objectives. Data were collected and analysed using Winsteps 3.90 software which is developed based on the Rasch measurement model. The results showed that students’ perceived themselves as moderately competent in solving the statistical problems using confidence interval and p-value approach even though their actual performance showed otherwise. Item measures for fit statistics also showed that the maximum estimated measures were found on two problems. These measures indicate that none of the students have attempted these problems correctly due to reasons which include their lack of understanding in confidence interval and probability values.
Evans-Lacko, Sara; Knapp, Martin; McCrone, Paul
2013-01-01
Objectives A period of economic recession may be particularly difficult for people with mental health problems as they may be at higher risk of losing their jobs, and more competitive labour markets can also make it more difficult to find a new job. This study assesses unemployment rates among individuals with mental health problems before and during the current economic recession. Methods Using individual and aggregate level data collected from 27 EU countries in the Eurobarometer surveys of 2006 and 2010, we examined changes in unemployment rates over this period among individuals with and without mental health problems. Results Following the onset of the recession, the gap in unemployment rates between individuals with and without mental health problems significantly widened (odds ratio: 1.12, 95% confidence interval: 1.03, 1.34). This disparity became even greater for males, and individuals with low levels of education. Individuals with mental health problems living in countries with higher levels of stigmatizing attitudes regarding dangerousness of people with mental illness were more vulnerable to unemployment in 2010, but not 2006. Greater agreement that people with mental health problems have themselves to blame, was associated with lower likelihood of unemployment for individuals with and without mental health problems. Conclusion These findings study suggest that times of economic hardship may intensify social exclusion of people with mental health problems, especially males and individuals with lower education. Interventions to combat economic exclusion and to promote social participation of individuals with mental health problems are even more important during times of economic crisis, and these efforts should target support to the most vulnerable groups. PMID:23922801
Ochi, Manami; Fujiwara, Takeo
2016-08-01
Research in parental social support has chiefly examined received social support. Studies have suggested that provided social support may also be protective for child mental health problems. We aim to investigate the association between parental social interaction (both received and provided social support) and offspring behavior problems. We analyzed the data of 982 households, including 1538 children aged 4 to 16 years, from the Japanese Study of Stratification, Health, Income, and Neighborhood (J-SHINE) survey conducted over 2010-2011. We used a 5-point Likert scale to assess social interaction including parental emotional and instrumental support received from and provided to the spouse, other co-residing family members, non-co-residing family members or relatives, neighbors, and friends. Behavior problems in offspring were assessed using parental responses to the Strengths and Difficulties Questionnaire. Associations between parental social interaction and behavior problems were analyzed using ordered logistic regression. We found that higher maternal social interaction is significantly associated with lower odds of both difficult and prosocial behavior problems, while the same associations were not found for paternal social interaction. Further, maternal provided social support showed an independent negative association with prosocial behavior problems in offspring, even when adjusted for received maternal social support and paternal social interaction. This study showed that maternal social interaction, but not paternal social interaction, might have a protective effect on offspring behavior problems. Further study is required to investigate the effect of the intervention to increase social participation among mothers whose children have behavior problems.
Biomedical Applications of NASA Science and Technology
NASA Technical Reports Server (NTRS)
Brown, James N., Jr.
1968-01-01
During the period 15 September 1968 to 14 December 1968, the NASA supported Biomedical Application Team at the Research Triangle Institute has identified 6 new problems, performed significant activities on 15 of the active problems identified previously, performed 5 computer searches of the NASA aerospace literature, and maintained one current awareness search. As a partial result of these activities, one technology transfer was accomplished. As a part of continuing problem review, 13 problems were classified inactive. Activities during the quarter involved all phases of team activity with respect to biomedical problems. As has been observed in preceding years, it has been exceedingly difficult to arrange meetings with medical investigators during the fourth quarter of the calendar year. This is a result of a combination of factors. Teaching requirements, submission of grant applications and holidays are the most significant factors involved. As a result, the numbers of new problems identified and of transfers and potential transfers are relatively low during this quarter. Most of our activities have thus been directed toward obtaining information related to problems already identified. Consequently, during the next quarter we will follow up on these activities with the expectation that transfers will be accomplished on a number of them. In addition, the normal availability of researchers to the team is expected to be restored during this quarter, permitting an increase in new problem identification activities as well as follow-up with other researchers on old problems. Another activity scheduled for the next quarter is consultation with several interested biomedical equipment manufacturers to explore means of effective interaction between the Biomedical Application Team and these companies.
Increasing the amount of payment to research subjects
Resnick, DB
2014-01-01
This article discusses some ethical issues that can arise when researchers decide to increase the amount of payment offered to research subjects to boost enrollment. Would increasing the amount of payment be unfair to subjects who have already consented to participate in the study? This article considers how five different models of payment—the free market model, the wage payment model, the reimbursement model, the appreciation model, and the fair benefits model—would approach this issue. The article also considers several practical problems related to changing the amount of payment, including determining whether there is enough money in the budget to offer additional payments to subjects who have already enrolled, ascertaining how difficult it will be to re-contact subjects, and developing a plan of action for responding to subjects who find out they are receiving less money and demand an explanation. PMID:18757614
Contraception for the older woman.
Glasier, A; Gebbie, A
1996-04-01
Contraception presents particular problems for women over the age of 40. Although fertility is declining and the risk of pregnancy may be small, the consequences of an unplanned pregnancy may be socially devastating and medically ill-advised. Menstrual dysfunction and psychosexual difficulties increase with age and may exacerbate the side-effects of some methods of contraception. The long-term risks of combined hormonal contraception, particularly cardiovascular disease, become more pertinent to women whose natural risk of disease increases with age. Patterns of sexual activity and contraceptive use change with age. The advantages and disadvantages of currently available methods of contraception are difficult to quantify, and the choice of method is very much a matter for individual concern. The increasing prevalence of HRT may complicate matters for some women who are unsure for how long to continue using contraception. Contraceptives of the future may be designed to improve the reproductive health of all women, particularly those approaching the menopause.
Who's talking? Communication and the casual/part-time nurse: a literature review.
Batch, Mary; Barnard, Alan; Windsor, Carol
2009-08-01
The rapidly evolving nursing working environment has seen the increased use of flexible non standard employment, including part-time, casual and itinerate workers. Evidence suggests that the nursing workforce has been at the forefront of the flexibility push which has seen the appearance of a dual workforce and marginalization of part-time and casual workers by their full-time peers and managers. The resulting fragmentation has meant that effective communication management has become difficult. Additionally, it is likely that poor organisational communication exacerbated by the increased use of non standard staff, is a factor underlying current discontent in the nursing industry and may impact on both recruitment and retention problems as well as patient outcomes. This literature review explores the relationship between the increasing casualisation of the nursing workforce and, among other things, the communication practices of nurses within healthcare organisations.
An anatomy of countertransference: staff reactions to difficult psychiatric hospital patients.
Colson, D B; Allen, J G; Coyne, L; Dexter, N; Jehl, N; Mayer, C A; Spohn, H
1986-09-01
Countertransference among hospital staff was investigated as part of ongoing research on difficult-to-treat psychiatric hospital patients. Staff's ratings of their emotional reactions to 127 patients on long-term units were analyzed by factor analysis, and the resulting factors were correlated by discipline with patient problem behaviors. Among the conclusions were that different forms of psychopathology elicit characteristic patterns of emotional reaction from staff; that some dimensions of psychopathology, particularly suicidal-depressed behavior and violence-agitation, elicit different emotional reactions among different disciplines, thus laying the groundwork for division among staff; and that the more difficult the process of hospital treatment, the more likely staff will experience a variety of emotions.
Heuristics in Problem Solving: The Role of Direction in Controlling Search Space
ERIC Educational Resources Information Center
Chu, Yun; Li, Zheng; Su, Yong; Pizlo, Zygmunt
2010-01-01
Isomorphs of a puzzle called m+m resulted in faster solution times and an easily reproduced solution path in a labeled version of the problem compared to a more difficult binary version. We conjecture that performance is related to a type of heuristic called direction that not only constrains search space in the labeled version, but also…
Reframing the Path to School Leadership: A Guide for Teachers and Principals.
ERIC Educational Resources Information Center
Bolman, Lee G.; Deal, Terrence E.
The best leaders use multiple frames or lenses to view common challenges and to solve their most difficult problems. This book contains a series of dialogs between a novice and a master teacher, and between a new and a seasoned principal as they demonstrate how framing and reframing challenges can bring clarity, help to anticipate problems, and…
ERIC Educational Resources Information Center
Chan, Man Ching Esther; Clarke, David; Cao, Yiming
2018-01-01
Interactive problem solving and learning are priorities in contemporary education, but these complex processes have proved difficult to research. This project addresses the question "How do we optimise social interaction for the promotion of learning in a mathematics classroom?" Employing the logic of multi-theoretic research design,…
Practical Math Skills: Situations--Strategies--Solutions. Junior High Level. Grades 7-8-9.
ERIC Educational Resources Information Center
Duncan, Jim
This material is a supplement to existing mathematics programs for young learners. The activities presented are based on assumptions about the young problem solver which are difficult to address in standard mathematics texts. In these pages it is assumed that each learner brings to the problem-solving effort a very personal experience base and a…
Spectral methods for partial differential equations
NASA Technical Reports Server (NTRS)
Hussaini, M. Y.; Streett, C. L.; Zang, T. A.
1983-01-01
Origins of spectral methods, especially their relation to the Method of Weighted Residuals, are surveyed. Basic Fourier, Chebyshev, and Legendre spectral concepts are reviewed, and demonstrated through application to simple model problems. Both collocation and tau methods are considered. These techniques are then applied to a number of difficult, nonlinear problems of hyperbolic, parabolic, elliptic, and mixed type. Fluid dynamical applications are emphasized.
Evaluation of Natural Language Processors.
1980-11-01
techniques described. Common practice in describing natural language processors is to describe the programs, then give about 20 examples of correctly...make a decision based on performance as to which approaches are most promising for further research and development. The lack of evaluation leaves...successively more difficult problems. This approach might be compared to children taking achievement tests in school. A 90% score on problems involving
ERIC Educational Resources Information Center
Wai, Nu Nu; Hirakawa, Yukiko
2001-01-01
Studied the participation and performance of upper secondary school teachers in Japan through surveys completed by 360 Geography teachers. Findings suggest that the importance of developing problem-solving skills is widely recognized among these teachers. Implementing training in such skills is much more difficult. Developing effective teaching…
ERIC Educational Resources Information Center
Wong, Kristyn; Stacks, Ann M.; Rosenblum, Katherine L.; Muzik, Maria
2017-01-01
This study assessed the links between infant negative affect, parental reflective functioning (RF), and toddler behavior problems in a sample of 84 women and their infants. Mothers provided self-report demographic data and completed the Infant Behavior Questionnaire-Revised during a home visit when the infant was 7 months old. They also completed…
Remembering the Singing of Silenced Voices: Brundibár and Problems of Pedagogy
ERIC Educational Resources Information Center
Dobbs, Teryl L.
2013-01-01
In this essay I explore problems of pedagogy related to Hans Krása's "Brundibár" by drawing heavily upon the thinking of two divergent theoretical perspectives regarding Holocaust testimony as advanced by Giorgio Agamben (2002) and Shoshana Felman (1992). I theorize that lodged within a space of difficult knowledge coalesced through…
ERIC Educational Resources Information Center
Mason, Susan A.
Reaching an employee whose job performance is deteriorating due to substance abuse, personal concerns or emotional problems, is one of the most difficult and most avoided tasks presented supervisors, coworkers and/or union stewards. Yet, when such problems do exist and do effect job performance, (and perhaps the work and safety of coworkers) clear…
Recent applications of spectral methods in fluid dynamics
NASA Technical Reports Server (NTRS)
Zang, T. A.; Hussaini, M. Y.
1985-01-01
Origins of spectral methods, especially their relation to the method of weighted residuals, are surveyed. Basic Fourier and Chebyshev spectral concepts are reviewed and demonstrated through application to simple model problems. Both collocation and tau methods are considered. These techniques are then applied to a number of difficult, nonlinear problems of hyperbolic, parabolic, elliptic and mixzed type. Fluid dynamical applications are emphasized.
ERIC Educational Resources Information Center
Longmore, Myron J.
A retention plan was developed to quantify and qualify the attrition problem and to establish action plans to improve retention for a regional university serving many nontraditional students. Cameron University, a state institution in Oklahoma, provides both associate and bachelor degree programs. The attrition problems were difficult to identify…
ERIC Educational Resources Information Center
Holman, Gareth; Kohlenberg, Robert J.; Tsai, Mavis; Haworth, Kevin; Jacobson, Emily; Liu, Sarah
2012-01-01
Depression and cigarette smoking are recurrent, interacting problems that co-occur at high rates and--especially when depression is chronic--are difficult to treat and associated with costly health consequences. In this paper we present an integrative therapeutic framework for concurrent treatment of these problems based on evidence-based…
Multi Agent Reward Analysis for Learning in Noisy Domains
NASA Technical Reports Server (NTRS)
Tumer, Kagan; Agogino, Adrian K.
2005-01-01
In many multi agent learning problems, it is difficult to determine, a priori, the agent reward structure that will lead to good performance. This problem is particularly pronounced in continuous, noisy domains ill-suited to simple table backup schemes commonly used in TD(lambda)/Q-learning. In this paper, we present a new reward evaluation method that allows the tradeoff between coordination among the agents and the difficulty of the learning problem each agent faces to be visualized. This method is independent of the learning algorithm and is only a function of the problem domain and the agents reward structure. We then use this reward efficiency visualization method to determine an effective reward without performing extensive simulations. We test this method in both a static and a dynamic multi-rover learning domain where the agents have continuous state spaces and where their actions are noisy (e.g., the agents movement decisions are not always carried out properly). Our results show that in the more difficult dynamic domain, the reward efficiency visualization method provides a two order of magnitude speedup in selecting a good reward. Most importantly it allows one to quickly create and verify rewards tailored to the observational limitations of the domain.
Saturated fat -a never ending story?
Svendsen, Karianne; Arnesen, Erik; Retterstøl, Kjetil
2017-01-01
Science has no clear message regarding health effects of saturated fats, it seems. Different RCTs, prospective cohort studies and meta-analysis have led to contrasting conclusions. The aim of the present commentary is to discuss some possible reasons for an apparently never-ending fat controversy. They are of a purely scientific nature, which is important to recognize, but unfortunately hard to overcome. First is the placebo problem. In pharmaceutical science, evidence-based medicine is often synonymous with data on verified medical events from long-lasting double-blind randomized placebo controlled trials. In nutritional science the lack of double-blind design and lack of placebo food generate less conclusive data than those achieved in pharmaceutical science. Some scientists may apply the same type of scientific criteria used to evaluate the effects of drugs for foods. This leaves an impression of insufficient data since in this respect the fundamental criteria for evidence based medicine are not present. The next scientific problem is the energy balance equation. In contrast to pharmaceuticals, nutrients contain energy. An increased intake of one nutrient will lead to a decreased intake of another. The effect of change in only one nutrient is then difficult to isolate. Lastly, in nutritional science, generalizability is difficult compared to pharmaceutical science. Food culture interferes with lifestyle and food habits change over time. In conclusion, all available knowledge, from molecular experiments to population studies, must be taken in to account, to convert scientific data into dietary recommendations.
Legalizing altruistic surrogacy in response to evasive travel? An Icelandic proposal.
Kristinsson, Sigurður
2016-12-01
Surrogate motherhood has been prohibited by Icelandic law since 1996, but in recent years, Icelandic couples have sought transnational surrogacy in India and the United States despite uncertainties about legal parental status as they return to Iceland with infants born to surrogate mothers. This reflects global trends of increased reproductive tourism, which forces restrictive regimes not only to make decisions concerning the citizenship and parentage of children born to surrogate mothers abroad, but also to confront difficult moral issues concerning surrogacy, global justice, human rights and exploitation. In March 2015, a legislative proposal permitting altruistic surrogacy, subject to strict regulation and oversight, and prohibiting the solicitation of commercial surrogacy abroad, was presented in the Icelandic Parliament. The proposal aims to protect the interest of the child first, respect the autonomy of the surrogate second, and accommodate the intended parents' wishes third. After a brief overview of the development of the surrogacy issue in Iceland, this article describes the main features of this legislative proposal and evaluates it from an ethical and global justice perspective. It concludes that the proposed legislation is a response to problems generated by cross-border surrogacy in the context of evolving public attitudes toward the issue, and constitutes a valid attempt to reduce the moral hazards of surrogacy consistent with insights from current bioethical literature. Although the proposed legislation arguably represents an improvement over the current ban, however, difficult problems concerning evasive travel and global injustice are likely to persist until effective international coordination is achieved.
Predicting drug interactions in addiction treatment.
Lucas, Catherine J; Patel, Joanne; Martin, Jennifer H
2017-08-01
It is not uncommon to be treating people with addiction who also have significant other health problems, including heart, renal or liver failure, diabetes and vascular disease. These conditions require regular medications to be taken. This can be a problem for people living with addiction and difficult social circumstances affecting compliance, among other issues. Our perspective provides a summary of general pharmacological factors affecting medicine taking in people with addiction problems, to provide a guide for hospital doctors in this setting. © 2017 Royal Australasian College of Physicians.
Some unsolved problems in discrete mathematics and mathematical cybernetics
NASA Astrophysics Data System (ADS)
Korshunov, Aleksei D.
2009-10-01
There are many unsolved problems in discrete mathematics and mathematical cybernetics. Writing a comprehensive survey of such problems involves great difficulties. First, such problems are rather numerous and varied. Second, they greatly differ from each other in degree of completeness of their solution. Therefore, even a comprehensive survey should not attempt to cover the whole variety of such problems; only the most important and significant problems should be reviewed. An impersonal choice of problems to include is quite hard. This paper includes 13 unsolved problems related to combinatorial mathematics and computational complexity theory. The problems selected give an indication of the author's studies for 50 years; for this reason, the choice of the problems reviewed here is, to some extent, subjective. At the same time, these problems are very difficult and quite important for discrete mathematics and mathematical cybernetics. Bibliography: 74 items.
Unstructured Adaptive Meshes: Bad for Your Memory?
NASA Technical Reports Server (NTRS)
Biswas, Rupak; Feng, Hui-Yu; VanderWijngaart, Rob
2003-01-01
This viewgraph presentation explores the need for a NASA Advanced Supercomputing (NAS) parallel benchmark for problems with irregular dynamical memory access. This benchmark is important and necessary because: 1) Problems with localized error source benefit from adaptive nonuniform meshes; 2) Certain machines perform poorly on such problems; 3) Parallel implementation may provide further performance improvement but is difficult. Some examples of problems which use irregular dynamical memory access include: 1) Heat transfer problem; 2) Heat source term; 3) Spectral element method; 4) Base functions; 5) Elemental discrete equations; 6) Global discrete equations. Nonconforming Mesh and Mortar Element Method are covered in greater detail in this presentation.
Constraint Programming to Solve Maximal Density Still Life
NASA Astrophysics Data System (ADS)
Chu, Geoffrey; Petrie, Karen Elizabeth; Yorke-Smith, Neil
The Maximum Density Still Life problem fills a finite Game of Life board with a stable pattern of cells that has as many live cells as possible. Although simple to state, this problem is computationally challenging for any but the smallest sizes of board. Especially difficult is to prove that the maximum number of live cells has been found. Various approaches have been employed. The most successful are approaches based on Constraint Programming (CP). We describe the Maximum Density Still Life problem, introduce the concept of constraint programming, give an overview on how the problem can be modelled and solved with CP, and report on best-known results for the problem.
Physical Unclonable Function with Multiplexing Units and its Evaluation
NASA Astrophysics Data System (ADS)
Yoshikawa, Masaya; Asai, Toshiya; Shiozaki, Mitsuru; Fujino, Takeshi
Recently, semiconductor counterfeiting has become an increasingly serious problem. Therefore, techniques to prevent the counterfeit by using random characteristic patterns that are difficult to control artificially have attracted attention. The physical unclonable function (PUF) is one of the techniques. It is a method to derive ID information peculiar to a device by detecting random physical features that cannot be controlled during the device's manufacture. Because information such as the ID information is difficult to replicate, PUF is used as a technique to prevent counterfeiting. Several studies have been reported on PUF. Arbiter PUF, which utilizes the difference in signal propagation delay between selectors, is the typical method of composing PUF using delay characteristics. This paper proposed a new PUF which is based on the arbiter PUF. The proposed PUF introduces new multiplexing selector units. It attempts to generate an effective response using the orders of three signal arrivals. Experiments using FPGAs verify the validity of the proposed PUF. Although Uniqueness is deteriorated, Correctness, Steadiness, Randomness and Resistance against the machine learning attacks are improved in comparison with conventional one.
Taking error into account when fitting models using Approximate Bayesian Computation.
van der Vaart, Elske; Prangle, Dennis; Sibly, Richard M
2018-03-01
Stochastic computer simulations are often the only practical way of answering questions relating to ecological management. However, due to their complexity, such models are difficult to calibrate and evaluate. Approximate Bayesian Computation (ABC) offers an increasingly popular approach to this problem, widely applied across a variety of fields. However, ensuring the accuracy of ABC's estimates has been difficult. Here, we obtain more accurate estimates by incorporating estimation of error into the ABC protocol. We show how this can be done where the data consist of repeated measures of the same quantity and errors may be assumed to be normally distributed and independent. We then derive the correct acceptance probabilities for a probabilistic ABC algorithm, and update the coverage test with which accuracy is assessed. We apply this method, which we call error-calibrated ABC, to a toy example and a realistic 14-parameter simulation model of earthworms that is used in environmental risk assessment. A comparison with exact methods and the diagnostic coverage test show that our approach improves estimation of parameter values and their credible intervals for both models. © 2017 by the Ecological Society of America.
NASA Astrophysics Data System (ADS)
Yang, J.; Zhang, H.; Wang, C.; Tang, D.
2018-04-01
With the continuous development of social economy, the interaction between mankind and nature has become increasingly evident. Disastrous global catastrophes have occurred from time to time, causing huge losses to people's lives and property. All governments recognize the importance of the establishment of disaster early warning and release mechanisms, and it is also an urgent issue to improve the comprehensive service level of emergency response and disaster relief. However, disaster early warning and emergency relief information is usually generated by different departments, and the diverse data sources, difficult integration, and limited release speed have always been difficult issues to be solved. Block data is the aggregation of various distributed (point data) and segmentation (data) big data on a specific platform and make them happen continuous polymerization effect, block data theory is a good solution to cross-sectoral, cross-platform Disaster information data sharing and integration problems. This paper attempts to discuss the integrated service mechanism of disaster information aggregation and disaster relief based on block data theory and introduces a location-based integrated service system for disaster early warning and disaster relief.
A fire danger rating system for Hawaii
Robert E. Burgan; Francis M. Fujioka; George H. Hirata
1974-01-01
Extremes in rainfall on the Hawaiian Islands make it difficult to judge forest fire danger conditions. The use of an automatic data collection and computer processing system helps to monitor the problem.
Nanotechnology: Its Promise and Challenges
DOE Office of Scientific and Technical Information (OSTI.GOV)
Colvin, Vicki
2009-05-14
Vicki Colvin of Rice University talks about how nanotechnology-enabled systems, with dimensions on the scale of a billionth of a meter, offer great promise for solving difficult social problems and creating enormous possibilities.
Novel approach to recurrent cavoatrial renal cell carcinoma.
Alejo, Jennifer L; George, Timothy J; Beaty, Claude A; Allaf, Mohamad E; Black, James H; Shah, Ashish S
2012-05-01
Renal cell carcinoma (RCC) with cavoatrial extension is a rare and complex problem. Complete resection is difficult but correlates with favorable patient outcomes. We present 2 cases of successful reoperative resections of recurrent RCC in patients with level III-IV cavoatrial involvement. We used a thoracoabdominal approach, peripheral cannulation, and hypothermic circulatory arrest. We advocate this novel approach as a successful means of avoiding a more difficult reoperation. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
The "difficult" patient reconceived: an expanded moral mandate for clinical ethics.
Fiester, Autumn
2012-01-01
Between 15 and 60% of patients are considered "difficult" by their treating physicians. Patient psychiatric pathology is the conventional explanation for why patients are deemed "difficult." But the prevalence of the problem suggests the possibility of a less pathological cause. I argue that the phenomenon can be better explained as a response to problematic interactions related to health care delivery. If there are grounds to reconceive the "difficult" patient as reacting to the perception of ill treatment, then there is an ethical obligation to address this perception of harm. Resolution of such conflicts currently lies with the provider and patient. But the ethical stakes place these conflicts into the province of the ethics consult service. As the resource for addressing ethical dilemmas, there is a moral mandate to offer assistance in the resolution of these ethically charged conflicts that is no less pressing than the more familiar terrain of clinical ethics consultation.
Wind Farm Turbine Type and Placement Optimization
NASA Astrophysics Data System (ADS)
Graf, Peter; Dykes, Katherine; Scott, George; Fields, Jason; Lunacek, Monte; Quick, Julian; Rethore, Pierre-Elouan
2016-09-01
The layout of turbines in a wind farm is already a challenging nonlinear, nonconvex, nonlinearly constrained continuous global optimization problem. Here we begin to address the next generation of wind farm optimization problems by adding the complexity that there is more than one turbine type to choose from. The optimization becomes a nonlinear constrained mixed integer problem, which is a very difficult class of problems to solve. This document briefly summarizes the algorithm and code we have developed, the code validation steps we have performed, and the initial results for multi-turbine type and placement optimization (TTP_OPT) we have run.
Wind farm turbine type and placement optimization
Graf, Peter; Dykes, Katherine; Scott, George; ...
2016-10-03
The layout of turbines in a wind farm is already a challenging nonlinear, nonconvex, nonlinearly constrained continuous global optimization problem. Here we begin to address the next generation of wind farm optimization problems by adding the complexity that there is more than one turbine type to choose from. The optimization becomes a nonlinear constrained mixed integer problem, which is a very difficult class of problems to solve. Furthermore, this document briefly summarizes the algorithm and code we have developed, the code validation steps we have performed, and the initial results for multi-turbine type and placement optimization (TTP_OPT) we have run.
Gravity inversion of a fault by Particle swarm optimization (PSO).
Toushmalani, Reza
2013-01-01
Particle swarm optimization is a heuristic global optimization method and also an optimization algorithm, which is based on swarm intelligence. It comes from the research on the bird and fish flock movement behavior. In this paper we introduce and use this method in gravity inverse problem. We discuss the solution for the inverse problem of determining the shape of a fault whose gravity anomaly is known. Application of the proposed algorithm to this problem has proven its capability to deal with difficult optimization problems. The technique proved to work efficiently when tested to a number of models.
[Follow-up of children conceived by assisted reproductive technologies].
Bouillon, C; Fauque, P
2013-05-01
Since the birth of the first baby conceived by in vitro fertilization (IVF) 30 years ago (Louise Brown in 1978), there has been a rapid and constant increase in the number of couples using assisted reproductive technologies (ART). Around four million of children have been born from couples experiencing fertility problems, through the use of ART, comprising roughly 2-3 % of all births in Europe and U.S. That highlights that these modes of fertilization are now well assumed by our societies. However, several questions on health of these children remain to be elucidated. As evoked in this review, even if methodological limitations exist, numerous studies have reported increased risks of birth defects, like prematurity, foetal hypotrophy, neonatal complications, congenital malformations and epigenetic diseases among ART-conceived children as compared to naturally conceived children. Nowadays, it is difficult to determine if these increased risks found in ART infants are a consequence of the ART procedures or are inherent to the infertility problems per se. However, absolute risks remain moderate and reassuring as well as the data on follow-up into infancy and early childhood. Nevertheless, because the effects may occur at the adulthood, there is a need for long-term follow-up of children born after ART. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Reliable low precision simulations in land surface models
NASA Astrophysics Data System (ADS)
Dawson, Andrew; Düben, Peter D.; MacLeod, David A.; Palmer, Tim N.
2017-12-01
Weather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing computing resources. However, there have been some concerns in the weather and climate modelling community over the suitability of lower precision for climate models, particularly for representing processes that change very slowly over long time-scales. These processes are difficult to represent using low precision due to time increments being systematically rounded to zero. Idealised simulations are used to demonstrate that a model of deep soil heat diffusion that fails when run in single precision can be modified to work correctly using low precision, by splitting up the model into a small higher precision part and a low precision part. This strategy retains the computational benefits of reduced precision whilst preserving accuracy. This same technique is also applied to a full complexity land surface model, resulting in rounding errors that are significantly smaller than initial condition and parameter uncertainties. Although lower precision will present some problems for the weather and climate modelling community, many of the problems can likely be overcome using a straightforward and physically motivated application of reduced precision.
Dix, Theodore; Yan, Ni
2014-02-01
This study examined individual differences in how mothers' depressive symptoms affect children's early adjustment. It tested whether problematic development among children high in negative emotionality is accentuated by (a) maternal reactivity, the negative reactivity of mothers with depressive symptoms to difficult child characteristics; and (b) child vulnerability, the susceptibility of negatively emotional children to the negative parenting of mothers with depressive symptoms. Based on 1,364 participants from the NICHD Study of Early Child Care, results showed that mothers' depressive symptoms predicted greater risk for adjustment problems at age 3 among children who as infants were high rather than low in negative emotionality. Increased risk was evident for behavior problems, low responsiveness, high separation distress, and low social competence. Mediational tests suggested that increased risk reflected maternal reactivity: the stronger mothers' depressive symptoms, the more they responded with negative parenting to children high in negative emotionality. The proposal that child vulnerability mediates the greater impact of mothers' depressive symptoms on negatively emotional children was verified only for separation distress. The results support the proposal that, when mothers are high in depressive symptoms, aversive characteristics of children and their behavior increasingly influence early adjustment and do so because they elicit negative parent behavior.
EPA is a government leader in tapping the power of contributions from the public to help solve difficult problems that affect the environment and public health. Prize competitions allow federal agencies to pay only for successful solutions.
Spinal cord injury - Symptoms and causes
... are the leading cause of spinal cord injuries, accounting for almost half of new spinal cord injuries ... address these problems if they affect you. Respiratory system. Your injury may make it more difficult to ...
Monitoring Population Evolution in the Pearl River Delta from 2000 TO 2010
NASA Astrophysics Data System (ADS)
Yu, S.; Liu, F.; Zhang, Z.
2018-04-01
On behalf of more populous and developed regions in China, urban agglomerations have become important carries loading active economic activities and generous social benefits, and experienced sharper population increase, which results in great threat on local eco-environment construction. Therefore, exact and detailed population monitoring and analyzing, especially on the long sequence and multi frequency, is of great significance. The nighttime light time-series (NLT) products has been proven to be one of the most useful remotely sensed imagery to acquire persons at 1 km × 1 km scales. However, the existed problems, such as light saturation and blooming, greatly limit the accuracy of estimated results. Furthermore, it's difficult to spatialize population at km2 level due to the lack of basic data in non-census years. In order to solve all problems mentioned above, the populous Pearl River Delta was selected as the study area. A new residential extent extraction index (REEI) was proposed to solve light saturation and blooming problems. Population spatialization methods in census and non-census years were applied to acquire detailed population distribution from 2000 to 2010. Results showed the feasibility of the proposed methods in this work. During the decade, population was denser in the central PRD and sparser in the eastern, western and northern PRD. The speed of population increase was various in nine cities, but faster in 2000-2005 than 2005-2010.
ERIC Educational Resources Information Center
Lemheney, Alexander J.
2014-01-01
Physicians' offices are not the usual place where emergencies occur; thus how staff remains prepared and current regarding medical emergencies presents an ongoing challenge for private practitioners. The very nature of low-volume, high-risk, and problem-prone medical emergencies is that they occur with such infrequency it is difficult for staff to…
On Engaging with Others: A Wittgensteinian Approach to (Some) Problems with Deeply Held Beliefs
ERIC Educational Resources Information Center
Bowell, Tracy
2018-01-01
My starting point for this paper is a problem in critical thinking pedagogy--the difficult of bringing students to a point where they are able, and motivated, critically to evaluate their own deeply held beliefs. I first interrogate the very idea of a deeply held belief, drawing upon Wittgenstein's idea of a framework belief--a belief that forms…
All in a Knot of One Another's Labours: Self-Determination, Network Organising and Learning
ERIC Educational Resources Information Center
Pedler, Mike
2012-01-01
This essay is about how to learn to organise to tackle the intractable and most difficult problems of organisations and societies. It opens with a discussion of the nature of such problems, which are the spur for Revans' action learning and the focus of some recent thinking on leadership. Action learning works on the basis of peer relationships…
Forming YBa2Cu3O7-x Superconductors On Copper Substrates
NASA Technical Reports Server (NTRS)
Mackenzie, J. Devin; Young, Stanley G.
1991-01-01
Experimental process forms layer of high-critical-temperature ceramic superconductor YBa2Cu3O7-x on surface of copper substrate. Offers possible solution to problem of finishing ceramic superconductors to required final sizes and shapes (difficult problem because these materials brittle and cannot be machined or bent). Further research necessary to evaluate superconducting qualities of surface layers and optimize process.
Novel Technologies for Next Generation Memory
2013-07-25
charge in the capacitor) eventually fades unless the capacitor charge is refreshed , so the memory cells must be periodically refreshed (rewritten). The...reliability issues (such as poor data retention problem and refresh failure). In order to avoid those problems, a 3-dimensional channel structure...states during the refresh cycle (retention time). When the channel length is scaled down, it is difficult to guarantee sufficient retention time
ERIC Educational Resources Information Center
Grenier-Boley, Nicolas
2014-01-01
Certain mathematical concepts were not introduced to solve a specific open problem but rather to solve different problems with the same tools in an economic formal way or to unify several approaches: such concepts, as some of those of linear algebra, are presumably difficult to introduce to students as they are potentially interwoven with many…
Long-Ming Huang
2000-01-01
Improper cultivation of steep mountainous areas in Taiwan contributes to serious erosion and landslides. Regular patrol, detection, and administration of these problem areas has been an extremely difficult due to the steep and dangerous terrain of many of the forested watersheds in Taiwan. A remotely piloted vehicle (RPV) has been developed for various civil and...
Whale, Katie; Cramer, Helen; Joinson, Carol
2018-05-01
To explore the impact of the secondary school environment on young people with continence problems. In-depth qualitative semi-structured interviews. We interviewed 20 young people aged 11-19 years (11 female and nine male) with continence problems (daytime wetting, bedwetting, and/or soiling). Interviews were conducted by Skype (n = 11) and telephone (n = 9). Transcripts were analysed using inductive thematic analysis. We generated five main themes: (1) Boundaries of disclosure: friends and teachers; (2) Social consequences of avoidance and deceit; (3) Strict and oblivious gatekeepers; (4) Intimate actions in public spaces; and (5) Interrupted learning. Disclosure of continence problems at school to both friends and teachers was rare, due to the perceived stigma and fears of bullying and social isolation. The lack of disclosure to teachers and other school staff, such as pastoral care staff, creates challenges in how best to support these young people. Young people with continence problems require unrestricted access to private and adequate toilet facilities during the school day. There is a need for inclusive toilet access policies and improved toilet standards in schools. Addressing the challenges faced by young people with continence problems at school could help to remove the barriers to successful self-management of their symptoms. It is particularly concerning that young people with continence problems are at higher risk of academic underachievement. Increased support at school is needed to enable young people with continence problems to achieve their academic potential. Statement of Contribution What is already known on this subject? Continence problems are among the most common paediatric health problems Self-management of continence problems requires a structured schedule of fluid intake and bladder emptying Inadequate toilet facilities and restricted access make it difficult for young people to manage their incontinence What does this study add? Improvement is needed in teacher understanding of the needs of young people with continence problems Young people are reluctant to disclose continence problems due to perceived stigma and fear of social isolation Young people with continence problems may be at increased risk of academic underachievement. © 2017 The Authors. British Journal of Health Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.
Based on the Theory of TRIZ Solving the Problem of 18650 Battery Electrolyte Filling
NASA Astrophysics Data System (ADS)
Shao-hua, Cui; Jiang-ping, Mei; Ling-hua, Zhang; Xiao, Du
2017-12-01
As a type of standardized battery cylindrical 18650 lithium-ion battery is widely used in new energy vehicle industry, It can be produced in large quantities without changing type. Because of its special advantages than others. But due to the pressure of rising capacity, electrolyte filling (which is short for E/L) process has become more and more difficult. While reducing the production efficiency eases the problem of E/L, it also poses performance and security problems. So the issue cannot be solved using the common knowledge of the industry. In this paper, This article does not use lean manufacturing or 6Sigma methods, we use TRIZ theory to analyze the E/L difficulty problem in detail (using causal analysis, technical contradiction analysis, substance - field analysis, physical contradiction analysis and other tools). By creating an atmosphere of vacuum and pressure replace the existing E/L tooling for single cell mechanical structure, through blowing hot air method to increase the temperature of electrolyte, Dissolving the J/R into a electrolyte tank which is full of 0.3Mpa nitrogen. Under the premise of not reducing the production efficiency, at the same time ensuring performance and safety, we try to find out a method to solve the E/L difficulty problem, and would get better application in the construction of new production lines in the new factory.
Innovative strategies to overcome biofilm resistance.
Taraszkiewicz, Aleksandra; Fila, Grzegorz; Grinholc, Mariusz; Nakonieczna, Joanna
2013-01-01
We review the recent literature concerning the efficiency of antimicrobial photodynamic inactivation toward various microbial species in planktonic and biofilm cultures. The review is mainly focused on biofilm-growing microrganisms because this form of growth poses a threat to chronically infected or immunocompromised patients and is difficult to eradicate from medical devices. We discuss the biofilm formation process and mechanisms of its increased resistance to various antimicrobials. We present, based on data in the literature, strategies for overcoming the problem of biofilm resistance. Factors that have potential for use in increasing the efficiency of the killing of biofilm-forming bacteria include plant extracts, enzymes that disturb the biofilm structure, and other nonenzymatic molecules. We propose combining antimicrobial photodynamic therapy with various antimicrobial and antibiofilm approaches to obtain a synergistic effect to permit efficient microbial growth control at low photosensitizer doses.
Antibacterial Applications of Nanodiamonds.
Szunerits, Sabine; Barras, Alexandre; Boukherroub, Rabah
2016-04-12
Bacterial infectious diseases, sharing clinical characteristics such as chronic inflammation and tissue damage, pose a major threat to human health. The steady increase of multidrug-resistant bacteria infections adds up to the current problems modern healthcare is facing. The treatment of bacterial infections with multi-resistant germs is very difficult, as the development of new antimicrobial drugs is hardly catching up with the development of antibiotic resistant pathogens. These and other considerations have generated an increased interest in the development of viable alternatives to antibiotics. A promising strategy is the use of nanomaterials with antibacterial character and of nanostructures displaying anti-adhesive activity against biofilms. Glycan-modified nanodiamonds (NDs) revealed themselves to be of great promise as useful nanostructures for combating microbial infections. This review summarizes the current efforts in the synthesis of glycan-modified ND particles and evaluation of their antibacterial and anti-biofilm activities.
Forecasting natural hazards, performance of scientists, ethics, and the need for transparency
Guzzetti, Fausto
2016-01-01
Landslides are one of several natural hazards. As other natural hazards, landslides are difficult to predict, and their forecasts are uncertain. The uncertainty depends on the poor understanding of the phenomena that control the slope failures, and on the inherent complexity and chaotic nature of the landslides. This is similar to other natural hazards, including hurricanes, earthquakes, volcanic eruptions, floods, and droughts. Due to the severe impact of landslides on the population, the environment, and the economy, forecasting landslides is of scientific interest and of societal relevance, and scientists attempting to forecast landslides face known and new problems intrinsic to the multifaceted interactions between science, decision-making, and the society. The problems include deciding on the authority and reliability of individual scientists and groups of scientists, and evaluating the performances of individual scientists, research teams, and their institutions. Related problems lay in the increasing subordination of research scientists to politics and decision-makers, and in the conceptual and operational models currently used to organize and pay for research, based on apparently objective criteria and metrics, considering science as any other human endeavor, and favoring science that produces results of direct and immediate application. The paper argues that the consequences of these problems have not been considered fully. PMID:27695154
Forecasting natural hazards, performance of scientists, ethics, and the need for transparency.
Guzzetti, Fausto
2016-10-20
Landslides are one of several natural hazards. As other natural hazards, landslides are difficult to predict, and their forecasts are uncertain. The uncertainty depends on the poor understanding of the phenomena that control the slope failures, and on the inherent complexity and chaotic nature of the landslides. This is similar to other natural hazards, including hurricanes, earthquakes, volcanic eruptions, floods, and droughts. Due to the severe impact of landslides on the population, the environment, and the economy, forecasting landslides is of scientific interest and of societal relevance, and scientists attempting to forecast landslides face known and new problems intrinsic to the multifaceted interactions between science, decision-making, and the society. The problems include deciding on the authority and reliability of individual scientists and groups of scientists, and evaluating the performances of individual scientists, research teams, and their institutions. Related problems lay in the increasing subordination of research scientists to politics and decision-makers, and in the conceptual and operational models currently used to organize and pay for research, based on apparently objective criteria and metrics, considering science as any other human endeavor, and favoring science that produces results of direct and immediate application. The paper argues that the consequences of these problems have not been considered fully.
Cerium Oxide Nanoparticle Nose-Only Inhalation Exposures ...
There is a critical need to assess the health effects associated with exposure of commercially produced NPs across the size ranges reflective of that detected in the industrial sectors that are generating, as well as incorporating, NPs into products. Generation of stable and low concentrations of size-fractionated nanoscale aerosols in nose-only chambers can be difficult, and when the aerosol agglomerates during generation, the problems are significantly increased. One problem is that many nanoscale aerosol generators have higher aerosol output and/or airflow than can be accommodated by a nose-only inhalation chamber, requiring much of the generated aerosol to be diverted to exhaust. Another problem is that mixing vessels used to modulate the fluctuating output from aerosol generators can cause substantial wall losses, consuming much of the generated aerosol. Other available aerosol generation systems can produce nanoscale aerosols from nanoparticles (NPs), however these NPs are generated in real time and do not approximate the physical and chemical characteristics of NPs that are commercially produced exposing the workers and the public. The health effects associated with exposure to commercial NP production, which are more morphologically and size heterogeneous, is required for risk assessment. To overcome these problems, a low-consumption dry-particulate nanoscale aerosol generator was developed to deliver stable concentrations in the range of 10–5000 µg
Sidor, Anna; Fischer, Cristina; Cierpka, Manfred
2017-01-01
Difficult conditions during childhood can limit an individual's development in many ways. Factors such as being raised in an at-risk family, child temperamental traits or maternal traits can potentially influence a child's later behaviour. The present study investigated the extent of regulatory problems in 6-month-old infants and their link to temperamental traits and impact on externalizing and internalizing problems at 36 months. Moderating effects of maternal distress and maternal depressive symptoms were tested as well. In a quasi-experimental, longitudinal study, a sample of 185 mother-infant dyads at psychosocial risk was investigated at 6 months with SFS (infants' regulatory problems) and at 3 years with CBCL (children's behavioural problems), EAS (children's temperament), ADS (maternal depressive symptoms) and PSI-SF (maternal stress). A hierarchical regression analysis yielded a significant association between infants' regulatory problems and both externalizing and internalizing behaviour problems at age 3 (accounting for 16% and 14% variance), with both externalizing and internalizing problems being linked to current maternal depressive symptoms (12 and 9% of the variance). Externalizing and internalizing problems were found to be related also to children's temperamental difficulty (18 and 13% of variance) and their negative emotionality. With temperamental traits having been taken into account, only feeding problems at 6 months contributed near-significant to internalizing problems at 3 years. Our results underscore the crucial role of temperament in the path between early regulatory problems and subsequent behavioural difficulties. Children's unfavourable temperamental predispositions such as negative emotionality and generally "difficult temperament" contributed substantially to both externalizing and internalizing behavioural problems in the high-risk sample. The decreased predictive power of regulatory problems following the inclusion of temperamental variables indicates a mediation effect of temperamental traits in the path between early regulatory problems and subsequent behavioural problems. Our results support the main effects of a child's temperament, and to some degree maternal depressive symptoms, rather than the diathesis stress model of interaction between risky environment and temperamental traits. Trial registration D10025651 (NZFH).
Health Care Issues in Southern Rural Black America.
ERIC Educational Resources Information Center
Turner, Henrie M.
1986-01-01
High infant and maternal mortality, poverty, isolation, a shortage of health professionals, inadequate health care facilities, and difficult geographic access to care are some of the health-related problems that plague Black rural southerners. (GC)
Accountability: A Mosaic Image
ERIC Educational Resources Information Center
Turner, Teri
1977-01-01
The problems involved in definition, implementation and control of accountability processes are discussed. It is stated that "...emotional involvement in accountability is one of the most difficult aspects to deal with, the chief emotion being fear". (Author/RW)
Askri, M; Belgacem, B; Zine, I; Haddad, M; Besrour, M
2008-01-01
We surveyed 415 mothers who regularly consult primary healthcare centres about their knowledge of addictive behavior in teenagers in relation to tobacco, alcohol and drugs. Most mothers considered the teenage period difficult. Apprehension of this period increased with the educational level of the mothers. Mothers did not often discuss the issue of addiction with their children, especially related to alcohol and drugs. Nevertheless, the mothers were aware of the risks of addiction. They considered information campaigns about this topic an efficient means of prevention. About half of the mothers had experience of addictive conduct involving a family member. They resolved the problems through family help or consultation with a specialist.
Oxidation of ammonium sulfite in aqueous solutions using ozone technology
NASA Astrophysics Data System (ADS)
Li, Yue; Shang, Kefeng; Lu, Na; Li, Jie; Wu, Yan
2013-03-01
How to deal with unstable ammonium sulfite, the byproduct of flue gas desulfuration by ammonia absorption methods, has been a difficult problem in recent years. Oxidation of ammonium sulfite in aqueous solutions using ozone produced by a surface discharge system was investigated in the paper. The oxidation efficiency of ammonium sulfite by ozone and traditional air aeration were compared, and the factors including ozone concentration, gas flow rate, initial concentration of ammonium sulfite solution and reaction temperature were discussed. The results show that the oxidation efficiency of ammonium sulfite by ozone technology reached nearly 100% under the optimum conditions, which had a significant increase compared with that by air aeration.
The detection and correction of outlying determinations that may occur during geochemical analysis
Harvey, P.K.
1974-01-01
'Wild', 'rogue' or outlying determinations occur periodically during geochemical analysis. Existing tests in the literature for the detection of such determinations within a set of replicate measurements are often misleading. This account describes the chances of detecting outliers and the extent to which correction may be made for their presence in sample sizes of three to seven replicate measurements. A systematic procedure for monitoring data for outliers is outlined. The problem of outliers becomes more important as instrumental methods of analysis become faster and more highly automated; a state in which it becomes increasingly difficult for the analyst to examine every determination. The recommended procedure is easily adapted to such analytical systems. ?? 1974.
[A Matter of Nerves - Applied Neurophysiology of Female Sexuality].
Bischof, Karoline
2015-06-17
Sexual problems are often attributed to psychological or physical deficits that are difficult to modify, or to a poor lover. In contrast, the neurophysiological interaction between body and brain can be understood as fundamental for the genital and emotional experience of sexuality. Neuropsychological discoveries and clinical observations show that elevated muscle tension, superficial breathing and reduced body movement, as employed by many individuals during sexual arousal, will limit the perception of arousal and the degree of sexual pleasure. In contrast, deep breathing and variations in movement and muscle tension support it. Through the use of self awareness exercises and physical learning steps, patients can integrate their sexuality and increases its resistance to psychological, medical and relational interferences.
Schooling in adolescence raises IQ scores
Brinch, Christian N.; Galloway, Taryn Ann
2012-01-01
Although some scholars maintain that education has little effect on intelligence quotient (IQ) scores, others claim that IQ scores are indeed malleable, primarily through intervention in early childhood. The causal effect of education on IQ at later ages is often difficult to uncover because analyses based on observational data are plagued by problems of reverse causation and self-selection into further education. We exploit a reform that increased compulsory schooling from 7 to 9 y in Norway in the 1960s to estimate the effect of education on IQ. We find that this schooling reform, which primarily affected education in the middle teenage years, had a substantial effect on IQ scores measured at the age of 19 y. PMID:22203952
NASA Astrophysics Data System (ADS)
Anezaki, Takashi; Wakitani, Kouichi; Nakamura, Masatoshi; Kubo, Hiroyasu
Because visual inspection systems are difficult to tune, they create many problems for the kaizen process. This results in increased development costs and time to assure that the inspection systems function properly. In order to improve inspection system development, we designed an easy-tuning system called a “Program-less” visual inspection system. The ROI macro command which consisted of eight kinds of shape recognition macro commands and decision, operation, control commands was built. Furthermore, the macro command editing executive system was developed by the operation of only the GUI without editing source program. The validity of the ROI macro command was proved by the application of 488 places.
'Visitation by God': rationalizing death in the Victorian asylum.
Smith, Cathy
2012-03-01
This article argues that death from insanity raised serious questions for the medical profession and for those who promoted the public asylum movement in the nineteenth century. While the medical emphasis on the somatic origins of insanity was increasingly accepted, limited observable signs of disease in the brain at post-mortem made it difficult to explain cause of death. This posed problems for a growing county asylum movement which was justified on the basis that insanity was a treatable disease and thus mortality rates would naturally decline. As asylum populations continued to grow and mortality rates remained little changed, statistics on lunacy ultimately became not the predicted measure of success but instead clear evidence of failure.
A global response to a global problem: the epidemic of overnutrition.
Chopra, Mickey; Galbraith, Sarah; Darnton-Hill, Ian
2002-01-01
It is estimated that by 2020 two-thirds of the global burden of disease will be attributable to chronic noncommunicable diseases, most of them strongly associated with diet. The nutrition transition towards refined foods, foods of animal origin, and increased fats plays a major role in the current global epidemics of obesity, diabetes and cardiovascular diseases, among other noncommunicable conditions. Sedentary lifestyles and the use of tobacco are also significant risk factors. The epidemics cannot be ended simply by encouraging people to reduce their risk factors and adopt healthier lifestyles, although such encouragement is undoubtedly beneficial if the targeted people can respond. Unfortunately, increasingly obesogenic environments, reinforced by many of the cultural changes associated with globalization, make even the adoption of healthy lifestyles, especially by children and adolescents, more and more difficult. The present paper examines some possible mechanisms for, and WHO's role in, the development of a coordinated global strategy on diet, physical activity and health. The situation presents many countries with unmanageable costs. At the same time there are often continuing problems of undernutrition. A concerted multisectoral approach, involving the use of policy, education and trade mechanisms, is necessary to address these matters. PMID:12571723
FuturICT — The road towards ethical ICT
NASA Astrophysics Data System (ADS)
van den Hoven, J.; Helbing, D.; Pedreschi, D.; Domingo-Ferrer, J.; Gianotti, F.; Christen, M.
2012-11-01
The pervasive use of information and communication technology (ICT) in modern societies enables countless opportunities for individuals, institutions, businesses and scientists, but also raises difficult ethical and social problems. In particular, ICT helped to make societies more complex and thus harder to understand, which impedes social and political interventions to avoid harm and to increase the common good. To overcome this obstacle, the large-scale EU flagship proposal FuturICT intends to create a platform for accessing global human knowledge as a public good and instruments to increase our understanding of the information society by making use of ICT-based research. In this contribution, we outline the ethical justification for such an endeavor. We argue that the ethical issues raised by FuturICT research projects overlap substantially with many of the known ethical problems emerging from ICT use in general. By referring to the notion of Value Sensitive Design, we show for the example of privacy how this core value of responsible ICT can be protected in pursuing research in the framework of FuturICT. In addition, we discuss further ethical issues and outline the institutional design of FuturICT allowing to address them.
Power System Decomposition for Practical Implementation of Bulk-Grid Voltage Control Methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vallem, Mallikarjuna R.; Vyakaranam, Bharat GNVSR; Holzer, Jesse T.
Power system algorithms such as AC optimal power flow and coordinated volt/var control of the bulk power system are computationally intensive and become difficult to solve in operational time frames. The computational time required to run these algorithms increases exponentially as the size of the power system increases. The solution time for multiple subsystems is less than that for solving the entire system simultaneously, and the local nature of the voltage problem lends itself to such decomposition. This paper describes an algorithm that can be used to perform power system decomposition from the point of view of the voltage controlmore » problem. Our approach takes advantage of the dominant localized effect of voltage control and is based on clustering buses according to the electrical distances between them. One of the contributions of the paper is to use multidimensional scaling to compute n-dimensional Euclidean coordinates for each bus based on electrical distance to perform algorithms like K-means clustering. A simple coordinated reactive power control of photovoltaic inverters for voltage regulation is used to demonstrate the effectiveness of the proposed decomposition algorithm and its components. The proposed decomposition method is demonstrated on the IEEE 118-bus system.« less
Fabrication of metal matrix composites by powder metallurgy: A review
NASA Astrophysics Data System (ADS)
Manohar, Guttikonda; Dey, Abhijit; Pandey, K. M.; Maity, S. R.
2018-04-01
Now a day's metal matrix components are used in may industries and it finds the applications in many fields so, to make it as better performable materials. So, the need to increase the mechanical properties of the composites is there. As seen from previous studies major problem faced by the MMC's are wetting, interface bonding between reinforcement and matrix material while they are prepared by conventional methods like stir casting, squeeze casting and other techniques which uses liquid molten metals. So many researchers adopt PM to eliminate these defects and to increase the mechanical properties of the composites. Powder metallurgy is one of the better ways to prepare composites and Nano composites. And the major problem faced by the conventional methods are uniform distribution of the reinforcement particles in the matrix alloy, many researchers tried to homogeneously dispersion of reinforcements in matrix but they find it difficult through conventional methods, among all they find ultrasonic dispersion is efficient. This review article is mainly concentrated on importance of powder metallurgy in homogeneous distribution of reinforcement in matrix by ball milling or mechanical milling and how powder metallurgy improves the mechanical properties of the composites.
Socializing the coast: Engaging the social science of tropical coastal research
NASA Astrophysics Data System (ADS)
Spalding, Ana K.; Biedenweg, Kelly
2017-03-01
The broad scale and rapid rate of change in the global environment is causing some of the world's most challenging problems, such as habitat degradation, loss of biodiversity, and food insecurity. These problems are especially pressing in coastal environments in the tropics, resulting in significant impacts on human wellbeing and ecological systems across the globe. The underlying causes of marine and coastal environmental change are both anthropogenic and natural; and, while it is difficult to parse out causal linkages as either exclusively human or naturally occurring, feedbacks between drivers only exacerbate the issues. Increasingly, scholars are turning to integrated research efforts, whereby multiple disciplines are used to answer pressing questions about and find solutions for the sustainability of human life and natural ecosystems across the coastal tropics. This article leverages the recent wave of interdisciplinary research to explore the various ways in which the social sciences have successfully contributed to a more complete understanding of coastal systems across the tropics. It also identifies opportunities for research that move beyond single disciplinary approaches to coastal science. The concluding discussion suggests social science knowledge areas that are underutilized in coastal research and provides suggestions for increasing the incorporation of social science in coastal research programs.
Odor compounds in waste gas emissions from agricultural operations and food industries.
Rappert, S; Müller, R
2005-01-01
In the last decades, large-scale agricultural operations and food industries have increased. These operations generate numerous types of odors. The reduction of land areas available for isolation of agricultural and food processing industrial operations from the public area and the increase in sensitivity and demand of the general public for a clean and pleasant environment have forced all of these industries to control odor emissions and toxic air pollutants. To develop environmentally sound, sustainable agricultural and food industrial operations, it is necessary to integrate research that focuses on modern analytical techniques and latest sensory technology of measurement and evaluation of odor and pollution, together with a fundamental knowledge of factors that are the basic units contributing to the production of odor and pollutants. Without a clear understanding of what odor is, how to measure it, and where it originates, it will be difficult to control the odor. The present paper reviews the available information regarding odor emissions from agricultural operations and food industries by giving an overview about odor problems, odor detection and quantification, and identifying the sources and the mechanisms that contribute to the odor emissions. Finally, ways of reducing or controlling the odor problem are discussed.
The Challenge of Wireless Reliability and Coexistence.
Berger, H Stephen
2016-09-01
Wireless communication plays an increasingly important role in healthcare delivery. This further heightens the importance of wireless reliability, but quantifying wireless reliability is a complex and difficult challenge. Understanding the risks that accompany the many benefits of wireless communication should be a component of overall risk management. The emerging trend of using sensors and other device-to-device communications, as part of the emerging Internet of Things concept, is evident in healthcare delivery. The trend increases both the importance and complexity of this challenge. As with most system problems, finding a solution requires breaking down the problem into manageable steps. Understanding the operational reliability of a new wireless device and its supporting system requires developing solid, quantified answers to three questions: 1) How well can this new device and its system operate in a spectral environment where many other wireless devices are also operating? 2) What is the spectral environment in which this device and its system are expected to operate? Are the risks and reliability in its operating environment acceptable? 3) How might the new device and its system affect other devices and systems already in use? When operated under an insightful risk management process, wireless technology can be safely implemented, resulting in improved delivery of care.
Outcomes of an early intervention program for children with disruptive behaviour.
Hayes, Louise; Giallo, Rebecca; Richardson, Kate
2010-12-01
Outcomes are presented from a public mental health early intervention program for children aged 5-9 years with disruptive behaviours. This was a school-based intervention initiative, delivered within a psychiatric child and adolescent mental health service and includes child, parent and teacher components. Participants were 235 children selected via school-based population assessments. A baseline period was used as a form of control that would demonstrate the stability of problem behaviours. Results showed that during a 26-week baseline period, teachers reported increasing levels of problem behaviour, and that the behaviour was creating increased difficulty in the classroom. The shorter 7-week baseline also showed the difficult behaviours were ongoing. Following the intervention, significant improvements in children's behaviour were seen on the Strengths and Difficulties Questionnaire reported by parents (η(2) = 0.30) and teachers (η(2) = 0.23), and on the parent Eyberg Child Behaviour Inventory (η(2) = 0.35), and teacher Sutter-Eyberg Student Behaviour Inventory (η(2) = 0.22). The outcomes show promising results from an early intervention program delivered in schools by a public mental health service and are discussed within the context of dissemination of evidence-based programs though mental health services.
Evaluation of Genetic Algorithm Concepts using Model Problems. Part 1; Single-Objective Optimization
NASA Technical Reports Server (NTRS)
Holst, Terry L.; Pulliam, Thomas H.
2003-01-01
A genetic-algorithm-based optimization approach is described and evaluated using a simple hill-climbing model problem. The model problem utilized herein allows for the broad specification of a large number of search spaces including spaces with an arbitrary number of genes or decision variables and an arbitrary number hills or modes. In the present study, only single objective problems are considered. Results indicate that the genetic algorithm optimization approach is flexible in application and extremely reliable, providing optimal results for all problems attempted. The most difficult problems - those with large hyper-volumes and multi-mode search spaces containing a large number of genes - require a large number of function evaluations for GA convergence, but they always converge.
Strategies for Limiting Engineers' Potential Liability for Indoor Air Quality Problems.
von Oppenfeld, Rolf R; Freeze, Mark E; Sabo, Sean M
1998-10-01
Engineers face indoor air quality (IAQ) issues at the design phase of building construction as well as during the investigation and mitigation of potential indoor air pollution problems during building operation. IAQ issues that can be identified are "building-related illnesses" that may include problems of volatile organic compounds (VOCs). IAQ issues that cannot be identified are termed "sick building syndrome." Frequently, microorganism-caused illnesses are difficult to confirm. Engineers who provide professional services that directly or indirectly impact IAQ face significant potential liability to clients and third parties when performing these duties. Potential theories supporting liability claims for IAQ problems against engineers include breach of contract and various common law tort theories such as negligence and negligent misrepresentation. Furthermore, an increasing number of federal, state, and local regulations affect IAQ issues and can directly increase the potential liability of engineers. A duty to disclose potential or actual air quality concerns to third parties may apply for engineers in given circumstances. Such a duty may arise from judicial precedent, the Model Guide for Professional Conduct for Engineers, or the Code of Ethics for Engineers. Practical strategies engineers can use to protect themselves from liability include regular training and continuing education in relevant regulatory, scientific, and case law developments; detailed documentation and recordkeeping practices; adequate insurance coverage; contractual indemnity clauses; contractual provisions limiting liability to the scope of work performed; and contractual provisions limiting the extent of liability for engineers' negligence. Furthermore, through the proper use of building materials and construction techniques, an engineer or other design professional can effectively limit the potential for IAQ liability.
Evolutionary optimization methods for accelerator design
NASA Astrophysics Data System (ADS)
Poklonskiy, Alexey A.
Many problems from the fields of accelerator physics and beam theory can be formulated as optimization problems and, as such, solved using optimization methods. Despite growing efficiency of the optimization methods, the adoption of modern optimization techniques in these fields is rather limited. Evolutionary Algorithms (EAs) form a relatively new and actively developed optimization methods family. They possess many attractive features such as: ease of the implementation, modest requirements on the objective function, a good tolerance to noise, robustness, and the ability to perform a global search efficiently. In this work we study the application of EAs to problems from accelerator physics and beam theory. We review the most commonly used methods of unconstrained optimization and describe the GATool, evolutionary algorithm and the software package, used in this work, in detail. Then we use a set of test problems to assess its performance in terms of computational resources, quality of the obtained result, and the tradeoff between them. We justify the choice of GATool as a heuristic method to generate cutoff values for the COSY-GO rigorous global optimization package for the COSY Infinity scientific computing package. We design the model of their mutual interaction and demonstrate that the quality of the result obtained by GATool increases as the information about the search domain is refined, which supports the usefulness of this model. We Giscuss GATool's performance on the problems suffering from static and dynamic noise and study useful strategies of GATool parameter tuning for these and other difficult problems. We review the challenges of constrained optimization with EAs and methods commonly used to overcome them. We describe REPA, a new constrained optimization method based on repairing, in exquisite detail, including the properties of its two repairing techniques: REFIND and REPROPT. We assess REPROPT's performance on the standard constrained optimization test problems for EA with a variety of different configurations and suggest optimal default parameter values based on the results. Then we study the performance of the REPA method on the same set of test problems and compare the obtained results with those of several commonly used constrained optimization methods with EA. Based on the obtained results, particularly on the outstanding performance of REPA on test problem that presents significant difficulty for other reviewed EAs, we conclude that the proposed method is useful and competitive. We discuss REPA parameter tuning for difficult problems and critically review some of the problems from the de-facto standard test problem set for the constrained optimization with EA. In order to demonstrate the practical usefulness of the developed method, we study several problems of accelerator design and demonstrate how they can be solved with EAs. These problems include a simple accelerator design problem (design a quadrupole triplet to be stigmatically imaging, find all possible solutions), a complex real-life accelerator design problem (an optimization of the front end section for the future neutrino factory), and a problem of the normal form defect function optimization which is used to rigorously estimate the stability of the beam dynamics in circular accelerators. The positive results we obtained suggest that the application of EAs to problems from accelerator theory can be very beneficial and has large potential. The developed optimization scenarios and tools can be used to approach similar problems.
Solving Word Problems using Schemas: A Review of the Literature
Powell, Sarah R.
2011-01-01
Solving word problems is a difficult task for students at-risk for or with learning disabilities (LD). One instructional approach that has emerged as a valid method for helping students at-risk for or with LD to become more proficient at word-problem solving is using schemas. A schema is a framework for solving a problem. With a schema, students are taught to recognize problems as falling within word-problem types and to apply a problem solution method that matches that problem type. This review highlights two schema approaches for 2nd- and 3rd-grade students at-risk for or with LD: schema-based instruction and schema-broadening instruction. A total of 12 schema studies were reviewed and synthesized. Both types of schema approaches enhanced the word-problem skill of students at-risk for or with LD. Based on the review, suggestions are provided for incorporating word-problem instruction using schemas. PMID:21643477
Dietary hypersensitivity in cats and dogs.
Mandigers, Paul; German, Alexander J
2010-10-01
Adverse reactions to food or dietary hypersensitivity are frequently seen problems in companion animal medicine and may be difficult to differentiate from inflammatory bowel disease (IBD). Dietary hypersensitivity can be divided into two subgroups: immunological and nonimmunological problems. Non-immunological problems can be subdivided into food intolerance, food poisoning, and dietary indiscretion. The immunological group can be subdivided into true food allergy (IgE mediated) and anaphylaxis (non-IgE mediated). This article gives an outline of what dietary hypersensitivity is, and more specifically food allergy and how to deal with patients with possible dietary hypersensitivity.
Parenting and Independent Problem-Solving in Preschool Children With Food Allergy
Power, Thomas G.; Hahn, Amy L.; Hoehn, Jessica L.; Thompson, Caitlin C.; Herbert, Linda J.; Law, Emily F.; Bollinger, Mary Elizabeth
2015-01-01
Objective To examine autonomy-promoting parenting and independent problem-solving in children with food allergy. Methods 66 children with food allergy, aged 3–6 years, and 67 age-matched healthy peers and their mothers were videotaped while completing easy and difficult puzzles. Coders recorded time to puzzle completion, children’s direct and indirect requests for help, and maternal help-giving behaviors. Results Compared with healthy peers, younger (3- to 4-year-old) children with food allergy made more indirect requests for help during the easy puzzle, and their mothers were more likely to provide unnecessary help (i.e., explain where to place a puzzle piece). Differences were not found for older children. Conclusions The results suggest that highly involved parenting practices that are medically necessary to manage food allergy may spill over into settings where high levels of involvement are not needed, and that young children with food allergy may be at increased risk for difficulties in autonomy development. PMID:25326001
Donate-Bartfield, Evelyn; Spellecy, Ryan; Shane, Nicholas J
2010-01-01
This article examines advantages associated with nonpharmacological behavioral management techniques and suggests that there are benefits to their use (such as achieving a more lasting solution to the problem of dental anxiety) that are not realized with medication-based interventions. Analyses that use Kantian and existential viewpoints for exploring the use of medication versus behavioral interventions for managing life problems yield parallel conclusions: there are advantages gained by using behavioral interventions that are not always associated with medication-based interventions. These analyses, taken together with an understanding of the psychology of dental anxiety management, suggest that using nonpharmacological techniques for the management of dental anxiety can maximize adherence to the ethical principles of beneficence and patient autonomy. The authors discuss the barriers that make nonpharmacological interventions for anxiety management difficult for dentists to routinely use, and suggest that additional training in these methods and increased collaboration with mental health professionals are needed for dentists.
Yeast as a potential vehicle for neglected tropical disease drug discovery.
Denny, P W; Steel, P G
2015-01-01
High-throughput screening (HTS) efforts for neglected tropical disease (NTD) drug discovery have recently received increased attention because several initiatives have begun to attempt to reduce the deficit in new and clinically acceptable therapies for this spectrum of infectious diseases. HTS primarily uses two basic approaches, cell-based and in vitro target-directed screening. Both of these approaches have problems; for example, cell-based screening does not reveal the target or targets that are hit, whereas in vitro methodologies lack a cellular context. Furthermore, both can be technically challenging, expensive, and difficult to miniaturize for ultra-HTS [(u)HTS]. The application of yeast-based systems may overcome some of these problems and offer a cost-effective platform for target-directed screening within a eukaryotic cell context. Here, we review the advantages and limitations of the technologies that may be used in yeast cell-based, target-directed screening protocols, and we discuss how these are beginning to be used in NTD drug discovery. © 2014 Society for Laboratory Automation and Screening.
Bullying and Victimization Among Children
Shetgiri, Rashmi
2013-01-01
Bullying among children is a significant public health problem world-wide. Bullying is most commonly defined as repeated, intentional aggression, perpetrated by a more powerful individual or group against a less powerful victim. Trends in victimization and moderate to frequent bullying may be decreasing slightly in the United States, but over 20% of children continue to be involved in bullying. Direct bullying consists of physical and verbal aggression, whereas indirect bullying involves relational aggression. Cyber bullying is an emerging problem which may be more difficult to identify and intervene with than traditional bullying. Bullies, victims, and bully-victims are at risk for negative short and long-term consequences such as depression, anxiety, low self-esteem, and delinquency. Various individual, parental, and peer factors increase the risk for involvement in bullying. Anti-bullying interventions are predominantly school-based and demonstrate variable results. Healthcare providers can intervene in bullying by identifying potential bullies or victims, screening them for co-morbidities, providing counseling and resources, and advocating for bullying prevention. PMID:24007839
Cross-Identification of Astronomical Catalogs on Multiple GPUs
NASA Astrophysics Data System (ADS)
Lee, M. A.; Budavári, T.
2013-10-01
One of the most fundamental problems in observational astronomy is the cross-identification of sources. Observations are made in different wavelengths, at different times, and from different locations and instruments, resulting in a large set of independent observations. The scientific outcome is often limited by our ability to quickly perform meaningful associations between detections. The matching, however, is difficult scientifically, statistically, as well as computationally. The former two require detailed physical modeling and advanced probabilistic concepts; the latter is due to the large volumes of data and the problem's combinatorial nature. In order to tackle the computational challenge and to prepare for future surveys, whose measurements will be exponentially increasing in size past the scale of feasible CPU-based solutions, we developed a new implementation which addresses the issue by performing the associations on multiple Graphics Processing Units (GPUs). Our implementation utilizes up to 6 GPUs in combination with the Thrust library to achieve an over 40x speed up verses the previous best implementation running on a multi-CPU SQL Server.
Clinical relevance of cannabis tolerance and dependence.
Jones, R T; Benowitz, N L; Herning, R I
1981-01-01
Psychoactive drugs are often widely used before tolerance and dependence is fully appreciated. Tolerance to cannabis-induced cardiovascular and autonomic changes, decreased intraocular pressure, sleep and sleep EEG, mood and behavioral changes is acquired and, to a great degree, lost rapidly with optimal conditions. Mechanisms appear more functional than metabolic. Acquisition rate depends on dose and dose schedule. Dependence, manifested by withdrawal symptoms after as little as 7 days of THC administration, is characterized by irritability, restlessness, insomnia, anorexia, nausea, sweating, salivation, increased body temperature, altered sleep and waking EEG, tremor, and weight loss. Mild and transient in the 120 subjects studied, the syndrome was similar to sedative drug withdrawal. Tolerance to drug side effects can be useful. Tolerance to therapeutic effects or target symptoms poses problems. Clinical significance of dependence is difficult to assess since drug-seeking behavior has many determinants. Cannabis-induced super sensitivity should be considered wherever chronic drug administration is anticipated in conditions like epilepsy, glaucoma or chronic pain. Cannabis pharmacology suggests ways of minimizing tolerance and dependence problems.
Visualization for Hyper-Heuristics: Back-End Processing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simon, Luke
Modern society is faced with increasingly complex problems, many of which can be formulated as generate-and-test optimization problems. Yet, general-purpose optimization algorithms may sometimes require too much computational time. In these instances, hyperheuristics may be used. Hyper-heuristics automate the design of algorithms to create a custom algorithm for a particular scenario, finding the solution significantly faster than its predecessor. However, it may be difficult to understand exactly how a design was derived and why it should be trusted. This project aims to address these issues by creating an easy-to-use graphical user interface (GUI) for hyper-heuristics and an easy-to-understand scientific visualizationmore » for the produced solutions. To support the development of this GUI, my portion of the research involved developing algorithms that would allow for parsing of the data produced by the hyper-heuristics. This data would then be sent to the front-end, where it would be displayed to the end user.« less
Optical techniques to feed and control GaAs MMIC modules for phased array antenna applications
NASA Astrophysics Data System (ADS)
Bhasin, K. B.; Anzic, G.; Kunath, R. R.; Connolly, D. J.
A complex signal distribution system is required to feed and control GaAs monolithic microwave integrated circuits (MMICs) for phased array antenna applications above 20 GHz. Each MMIC module will require one or more RF lines, one or more bias voltage lines, and digital lines to provide a minimum of 10 bits of combined phase and gain control information. In a closely spaced array, the routing of these multiple lines presents difficult topology problems as well as a high probability of signal interference. To overcome GaAs MMIC phased array signal distribution problems optical fibers interconnected to monolithically integrated optical components with GaAs MMIC array elements are proposed as a solution. System architecture considerations using optical fibers are described. The analog and digital optical links to respectively feed and control MMIC elements are analyzed. It is concluded that a fiber optic network will reduce weight and complexity, and increase reliability and performance, but higher power will be required.