WorldWideScience

Sample records for chapman-ferraro problem

  1. [Population problem, comprehension problem].

    Science.gov (United States)

    Tallon, F

    1993-08-01

    Overpopulation of developing countries in general, and Rwanda in particular, is not just their problem but a problem for developed countries as well. Rapid population growth is a key factor in the increase of poverty in sub-Saharan Africa. Population growth outstrips food production. Africa receives more and more foreign food, economic, and family planning aid each year. The Government of Rwanda encourages reduced population growth. Some people criticize it, but this criticism results in mortality and suffering. One must combat this ignorance, but attitudes change slowly. Some of these same people find the government's acceptance of family planning an invasion of their privacy. Others complain that rich countries do not have campaigns to reduce births, so why should Rwanda do so? The rate of schooling does not increase in Africa, even though the number of children in school increases, because of rapid population growth. Education is key to improvements in Africa's socioeconomic growth. Thus, Africa, is underpopulated in terms of potentiality but overpopulated in terms of reality, current conditions, and possibilities of overexploitation. Africa needs to invest in human resources. Families need to save, and to so, they must refrain from having many children. Africa should resist the temptation to waste, as rich countries do, and denounce it. Africa needs to become more independent of these countries, but structural adjustment plans, growing debt, and rapid population growth limit national independence. Food aid is a means for developed countries to dominate developing countries. Modernization through foreign aid has had some positive effects on developing countries (e.g., improved hygiene, mortality reduction), but these also sparked rapid population growth. Rwandan society is no longer traditional, but it is also not yet modern. A change in mentality to fewer births, better quality of life for living infants, better education, and less burden for women must occur

  2. Explaining the Mind: Problems, Problems

    OpenAIRE

    Harnad, Stevan

    2001-01-01

    The mind/body problem is the feeling/function problem: How and why do feeling systems feel? The problem is not just "hard" but insoluble (unless one is ready to resort to telekinetic dualism). Fortunately, the "easy" problems of cognitive science (such as the how and why of categorization and language) are not insoluble. Five books (by Damasio, Edelman/Tononi...

  3. Breathing Problems

    Science.gov (United States)

    ... you're not getting enough air. Sometimes mild breathing problems are from a stuffy nose or hard ... conditions such as asthma, emphysema or pneumonia cause breathing difficulties. So can problems with your trachea or ...

  4. IMP 8 magnetic observations of the high-latitude tail boundary: Locations and force balance

    International Nuclear Information System (INIS)

    IMP 8 (IMP J) magnetic field observations are used to determine the properties of the high-latitude tail boundary, which separates the tail lobe and the magnetosheath. Boundary crossings are marked by transitions from quiet lobe to disturbed magnetosheath fields. From five years (1978-1982) of IMP 8 observations, a data set of 244 boundary crossings has been identified in the XGSM range of -15 to -40 RE and |Z'GSM|>15 RE, when Z'GSM is the distance from the neutral sheet. The results suggest the following: (1) the tail cross section is slightly flattened in the north-south direction, (2) the high-latitude magnetotail field and boundary continue to flare antisunward out to 40 RE downstream of the Earth, and (3) interplanetary magnetic field (IMF) BZ and the solar wind dynamic pressure (but not, evidently, the solar wind magnetic pressure) control the boundary location. The dependence on IMF BZ is consistent with the buildup of magnetic fluxes in the magnetotail during periods of southward IMF BZ. Examination of the magnetic fields on each side of the boundary indicates the following: (1) the solar wind dynamic pressure determines the lobe-side field strength. (2) The flaring angle is estimated on the basis of the classical model of the Chapman-Ferraro problem. The result is consistent with the X dependence of the tail size and with the orientation of the lobe-side field (all have flaring angles of 7 degree-8 degree). (3) The IMF strength controls the sheath-side field strength, with a lesser contribution from the solar wind dynamic pressure. (4) The current flowing at the boundary primarily depends on the solar wind dynamic pressure. In summary, the present results indicate that the solar wind dynamic pressure is the most important factor determining the nature of the near-Earth magnetotail magnetopause

  5. Sociale problemer

    DEFF Research Database (Denmark)

    Christensen, Anders Bøggild; Rasmussen, Tove; Bundesen, Peter;

    Sociale problemer kan betragtes som selve udgangspunktet for socialt arbejde, hvor ambitionen er at råde bod på problemerne og sikre, at udsatte borgere får en bedre tilværelse. Det betyder også, at diskussionen af sociale problemer er afgørende for den sociale grundfaglighed. I denne bog sætter en...... række fagfolk på tværs af det danske socialfaglige felt fokus på sociale problemer. Det diskuteres, hvad vi overhovedet forstår ved sociale problemer, hvordan de opstår, hvilke konsekvenser de har, og ikke mindst hvordan man som fagprofessionel håndterer sociale problemer i det daglige arbejde. Bogen er...... skrevet som lærebog til professionsuddannelser, hvor sociale problemer udgør en dimension, bl.a. socialrådgiver-, pædagog- og sygeplejerskeuddannelserne....

  6. Popular Problems

    DEFF Research Database (Denmark)

    Skovhus, Randi Boelskifte; Thomsen, Rie

    2016-01-01

    This article introduces a method to critical reviews and explores the ways in which problems have been formulated in knowledge production on career guidance in Denmark over a 10-year period from 2004 to 2014. The method draws upon the work of Bacchi focussing on the ‘What's the problem represented...... provides a constructive basis for a critical analysis and discussion of the collective empirical knowledge production on career guidance, stimulating awareness of problems and potential solutions among the career guidance community....

  7. Knee Problems

    Science.gov (United States)

    ... in Chinese 繁體中文 ) What Are Knee Problems? (in Korean 한국어 ) What Are Knee Problems? (in Vietnamese bằng ... the knee. Ultrasound. A technique that uses sound waves to produce images of the soft tissue structures ...

  8. Sexual Problems

    Medline Plus

    Full Text Available ... can have intercourse but experience vaginismus during pelvic exams. Although vaginismus is considered a pain disorder, most ... and are used together to treat a problem. Education is important in understanding the anatomy and physiology ...

  9. Sexual Problems

    Medline Plus

    Full Text Available ... sexual problems. This specialist may be a physician, psychologist, social worker, or physical therapist. You may also ... see” their actions. In addition to improving sexual function, pelvic floor muscle rehabilitation can improve pelvic pain ...

  10. Sexual Problems

    Medline Plus

    Full Text Available ... Smoking Cessation Links to Professional Societies and Organizations Home › Sexual Problems Sexual concern causing distress can be ... Find a Health Care Provider Back to Top Home | About Us | Reproductive Health Topics | News & Publications | Resources ...

  11. Sexual Problems

    Medline Plus

    Full Text Available ... common problem that may be due to many factors, including physical, psychological, medical conditions, or medications. Men ... or as deep pain. Both psychological and physical factors can contribute to the condition. Current thinking is ...

  12. Sleep Problems

    Science.gov (United States)

    ... For Consumers Consumer Information by Audience For Women Sleep Problems Share Tweet Linkedin Pin it More sharing ... PDF 474KB) En Español Medicines to Help You Sleep Tips for Better Sleep Basic Facts about Sleep ...

  13. Sexual Problems

    Medline Plus

    Full Text Available ... pain disorders. If you are experiencing problems viewing this embedded video, please click here . Transcript Disorders of ... no sexual fantasies and desire for sexual activity. This lack of desire is beyond what normally happens ...

  14. Erection problems

    Science.gov (United States)

    ... problems can lead to ED, such as: Poor communication with your partner Feelings of doubt and failure Stress, fear, anxiety, or anger Expecting too much from sex. This can make sex a task instead of ...

  15. Sexual Problems

    Medline Plus

    Full Text Available ... Some women with vaginismus can tolerate a pelvic examination, while some women can have intercourse but experience ... and are used together to treat a problem. Education is important in understanding the anatomy and physiology ...

  16. Sexual Problems

    Medline Plus

    Full Text Available ... such as chronic testicular pain, and 4) other causes of sexual pain that include conditions of the ... should be taken seriously. When a sexual problem causes you distress, don’t be afraid to talk ...

  17. Swallowing problems

    Science.gov (United States)

    ... the home Dry mouth during cancer treatment Enteral nutrition - child - managing problems Gastrostomy feeding tube - bolus Jejunostomy feeding tube Mouth and neck radiation - discharge Multiple sclerosis - discharge Stroke - discharge Update Date 5/15/2014 ...

  18. Sexual Problems

    Medline Plus

    Full Text Available ... and Smoking Cessation Links to Professional Societies and Organizations Home › Sexual Problems Sexual concern causing distress can ... Site Terms & Conditions of Use | Web Design and Development by The Berndt Group

  19. Foot Problems

    Science.gov (United States)

    ... much higher rates of foot problems. For women, pain in the toes and ball of the foot is much more common than in men, and it gets worse with age. However, pain in the heel tends to decrease as we ...

  20. Sexual Problems

    Medline Plus

    Full Text Available ... to a specialist trained in the diagnosis and treatment of sexual problems. This specialist may be a ... in many different ways. Often, multiple types of treatment may be required and are used together to ...

  1. Sexual Problems

    Medline Plus

    Full Text Available ... problems. This specialist may be a physician, psychologist, social worker, or physical therapist. You may also find ... aids include lubricants, moisturizers, and sexual toys. Lubricants work by reducing friction between tissues. Many different types ...

  2. Sexual Problems

    Medline Plus

    Full Text Available ... and are used together to treat a problem. Education is important in understanding the anatomy and physiology ... counselors are mental health providers who have specialized training in working with people with sexual concerns. Cognitive ...

  3. Sexual Problems

    Medline Plus

    Full Text Available ... sexual arousal disorder have little or no genital responsiveness to stimulation and they don’t produce adequate ... problems. This specialist may be a physician, psychologist, social worker, or physical therapist. You may also find ...

  4. Sexual Problems

    Medline Plus

    Full Text Available ... a problem. Education is important in understanding the anatomy and physiology of sex and in having realistic ... lubricants in that they are absorbed into the skin. Moisturizers are a “maintenance therapy” that is applied ...

  5. Contact problems

    CERN Document Server

    Galin, Lev Aleksandrovich

    2008-01-01

    L.A. Galin's book on contact problems is a remarkable work. Actually there are two books: the first, published in 1953 deals with contact problems in the classical theory of elasticity; this is the one that was translated into English in 1961. The second book, published in 1980, included the first, and then had new sections on contact problems for viscoelastic materials, and rough contact problems; this section has not previously been translated into English. In this new translation, the original text and the mathematical analysis have been completely revised, new material has been added, and the material appearing in the 1980 Russian translation has been completely rewritten. In addition there are three essays by students of Galin, bringing the analysis up to date.

  6. Sexual Problems

    Medline Plus

    Full Text Available ... and Smoking Cessation Links to Professional Societies and Organizations Home › Sexual Problems Sexual concern causing distress can ... such as sexual abuse can be involved as well. Pain caused by lack of lubrication or by ...

  7. Sexual Problems

    Medline Plus

    Full Text Available ... concerns with your sexual partner. Because they are complex, sexual concerns are treated in many different ways. ... a healthcare professional. Although sexual problems can be complex, there are a variety of treatments that can ...

  8. Nipple problems

    Science.gov (United States)

    ... Inverted nipple; Nipple problems Images Female breast Intraductal papilloma Mammary gland Abnormal discharge from the nipple Normal ... 8. Read More Breast cancer Endocrine glands Intraductal papilloma Update Date 11/16/2014 Updated by: Cynthia ...

  9. Knapsack problems

    CERN Document Server

    Kellerer, Hans; Pisinger, David

    2004-01-01

    Thirteen years have passed since the seminal book on knapsack problems by Martello and Toth appeared. On this occasion a former colleague exclaimed back in 1990: "How can you write 250 pages on the knapsack problem?" Indeed, the definition of the knapsack problem is easily understood even by a non-expert who will not suspect the presence of challenging research topics in this area at the first glance. However, in the last decade a large number of research publications contributed new results for the knapsack problem in all areas of interest such as exact algorithms, heuristics and approximation schemes. Moreover, the extension of the knapsack problem to higher dimensions both in the number of constraints and in the num­ ber of knapsacks, as well as the modification of the problem structure concerning the available item set and the objective function, leads to a number of interesting variations of practical relevance which were the subject of intensive research during the last few years. Hence, two years ago ...

  10. Sexual Problems

    Medline Plus

    Full Text Available ... and Smoking Cessation Links to Professional Societies and Organizations Home › Sexual Problems Sexual concern causing distress can ... You can optimize the sexual setting by enhancing communication with your partner, promoting non-sexual intimacy, and ...

  11. Kidney Problems

    Science.gov (United States)

    ... Home & Community Home › Aging & Health A to Z › Kidney Problems Font size A A A Print Share Glossary Basic Facts & ... The kidneys also help maintain body fluids at normal levels. In addition, the kidneys play important roles in controlling blood pressure and ...

  12. Sexual Problems

    Medline Plus

    Full Text Available ... with your sexual partner. Because they are complex, sexual concerns are treated in many different ways. Often, multiple types of treatment may be required and are used together to treat a problem. Education is important in understanding the anatomy and physiology ...

  13. Dewey's Problem.

    Science.gov (United States)

    Cohen, David K.

    1998-01-01

    Maintains that Dewey tried to solve social problems related to the growth of industrialism, increasing economic inequality, and political inequality. Argues that Dewey aspired to create a counterculture to correct the human and social devastation of industrial capitalism through a curriculum and instruction that rooted academic learning in…

  14. Sexual Problems

    Medline Plus

    Full Text Available ... focuses on how one’s thinking influences feelings and behavior. Sensate focus exercises are structured “touching” activities that ... concerns should be taken seriously. When a sexual problem causes you distress, don’t be afraid to ...

  15. Sexual Problems

    Medline Plus

    Full Text Available ... important to note that psychological problems such as sexual abuse can be involved as well. Pain caused by lack of lubrication or by vaginismus is not included in this ... woman wants sexual penetration. Women with this condition can still achieve ...

  16. Mouth Problems

    Science.gov (United States)

    ... Here 1. Is the person an infant or child? Yes See "Mouth Problems in Infants and Children." No 2. Do you have pain in your ... usually heal on their own. To relieve discomfort, rinse with salt water or diluted hydrogen peroxide, or apply an over-the-counter oral gel. You may also use an analgesic such ...

  17. Agricultural problems

    International Nuclear Information System (INIS)

    Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned

  18. The Chicken Problem.

    Science.gov (United States)

    Reeves, Charles A.

    2000-01-01

    Uses the chicken problem for sixth grade students to scratch the surface of systems of equations using intuitive approaches. Provides students responses to the problem and suggests similar problems for extensions. (ASK)

  19. Problem, Problem Solving And Critical Thinking

    OpenAIRE

    TÜRNÜKLÜ, Elif B.; YEŞİLDERE, Sibel

    2005-01-01

    Critical thinking is an essential skill that all people from various sectors should have and need. Problem solving skill which is one of the main purpose of mathematics teaching can be effective in developing critical thinking. The purpose of this study is to emphasize the importance of problem solving in developing critical thinking skills and to expose critical thinking to the pre-service primary mathematics teachers. Aiming these, some mathematical critical thinking problems are prepa...

  20. PROBLEMS OF MIGRANT LABOR.

    Science.gov (United States)

    WALLS, FOREST

    PRESENT MIGRANT LABOR PROBLEMS AND SOLUTIONS WHICH HAVE BEEN PROPOSED ARE PRESENTED. THE FIRST PROBLEM AREA IS PROVIDING EDUCATION FOR MIGRANT CHILDREN. THIS IS HINDERED BY THE PROBLEM OF SECURING COMPLIANCE WITH MINIMUM EDUCATION LAWS AND BY LAWS PROHIBITING EMPLOYMENT OF CHILDREN DURING SCHOOL HOURS. A SECOND PROBLEM AREA IS THAT OF CHILD LABOR.…

  1. Differential equations problem solver

    CERN Document Server

    Arterburn, David R

    2012-01-01

    REA's Problem Solvers is a series of useful, practical, and informative study guides. Each title in the series is complete step-by-step solution guide. The Differential Equations Problem Solver enables students to solve difficult problems by showing them step-by-step solutions to Differential Equations problems. The Problem Solvers cover material ranging from the elementary to the advanced and make excellent review books and textbook companions. They're perfect for undergraduate and graduate studies.The Differential Equations Problem Solver is the perfect resource for any class, any exam, and

  2. [The mind -- body problem].

    Science.gov (United States)

    Pérez, Diana I

    2005-01-01

    In this paper I present, in the first place, two of the main problems in the philosophy of mind: 1) the problem of the criteria of the mental, and 2) the problem of the relationship between the mental and the physical. In the last part, I mention two problems highly discussed nowadays which, in my view, will produce the most important advance in the knowledge of our minds in the next decades: the problem of consciousness and its neural basis, and the problem of the origin and development of a theory of mind. PMID:16220149

  3. Locating Problems with Quality Circles.

    Science.gov (United States)

    White, Donald D.; Bednar, David A.

    1985-01-01

    Five categories of common quality circles problems are identified to help firms anticipate difficulties and avert circle failures. These categories include encountered internal problems, encountered external problems, created internal problems, created external problems, and interface problems. Solutions are suggested. (CT)

  4. Increases in Problem Drinking

    Science.gov (United States)

    ... Increases in Problem Drinking Join the Fight Against Superbugs Featured Website: Genetic and Rare Diseases Information Center ... Increases in Problem Drinking Join the Fight Against Superbugs Featured Website: Genetic and Rare Diseases Information Center ...

  5. Recognition of Problem Drinkers

    OpenAIRE

    Cornel, Michiel; van Zutphen, Wim M.

    1989-01-01

    General practitioners often see patients with problems related to drinking behaviour, but recognize only a small proportion of these problem drinkers. The authors discuss some mechanisms of this non-recognition phenomenon and suggest ways to enhance early recognition.

  6. Diabetes and Foot Problems

    Science.gov (United States)

    ... Disease, and Other Dental Problems Diabetic Eye Disease Diabetes and Foot Problems How can diabetes affect my feet? Too much glucose, also called ... you have any of these signs. How can diabetes change the shape of my feet? Nerve damage ...

  7. Solving Word Problems.

    Science.gov (United States)

    Karrison, Joan; Carroll, Margaret Kelly

    1991-01-01

    Students with language and learning disabilities may have difficulty solving mathematics word problems. Use of a sequential checklist, identifying clues and keywords, and illustrating a problem can all help the student identify and implement the correct computational process. (DB)

  8. Traveling with breathing problems

    Science.gov (United States)

    If you have breathing problems and you: Are short of breath most of the time Get short of breath when you walk 150 ... or less Have been in the hospital for breathing problems recently Use oxygen at home, even if ...

  9. Creativity for Problem Solvers

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2009-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes specially related to problem solving. Central publications related to the theme are briefly reviewed. Creative tools and approaches suitable to support problem solving are also presented. Finall...

  10. Health Problems in Pregnancy

    Science.gov (United States)

    Every pregnancy has some risk of problems. The causes can be conditions you already have or conditions you develop. ... pregnant with more than one baby, previous problem pregnancies, or being over age 35. They can affect ...

  11. Challenging problems in algebra

    CERN Document Server

    Posamentier, Alfred S

    2012-01-01

    Over 300 unusual problems, ranging from easy to difficult, involving equations and inequalities, Diophantine equations, number theory, quadratic equations, logarithms, more. Detailed solutions, as well as brief answers, for all problems are provided.

  12. Algorithmic Problem Complexity

    OpenAIRE

    Burgin, Mark

    2008-01-01

    People solve different problems and know that some of them are simple, some are complex and some insoluble. The main goal of this work is to develop a mathematical theory of algorithmic complexity for problems. This theory is aimed at determination of computer abilities in solving different problems and estimation of resources that computers need to do this. Here we build the part of this theory related to static measures of algorithms. At first, we consider problems for finite words and stud...

  13. Children with behavorial problem

    OpenAIRE

    Cerar, Kristina

    2011-01-01

    Behavioral problems are becoming more and more common phenomena in children education. When behavioral problems occur it is very important to have the appropriate approach that mitigates or completely removes them. The key to this is to know as much as possible about children development and behavioral problems. The theoretical part contains the features of a child's development and then I focused on behavioral problems and the causes that bring to such results. I described methods to remove...

  14. Thinking and problem solving

    OpenAIRE

    Frensch, Peter; Funke, Joachim

    2005-01-01

    Human thinking, and in particular, the human ability to solve complex, real-life problems contributes more than any other human ability to the development of human culture and the growth and development of human life on earth. However, the human ability to solve complex problems is still not well understood, partly because it has for a long time been largely ignored by traditional problem-solving research in the field of psychology. In this article, we present a definition of complex problem ...

  15. Mathematics as Problem Solving.

    Science.gov (United States)

    Soifer, Alexander

    This book contains about 200 problems. It is suggested that it be used by students, teachers or anyone interested in exploring mathematics. In addition to a general discussion on problem solving, there are problems concerned with number theory, algebra, geometry, and combinatorics. (PK)

  16. Optimal obstacle control problem

    Institute of Scientific and Technical Information of China (English)

    ZHU Li; LI Xiu-hua; GUO Xing-ming

    2008-01-01

    In the paper we discuss some properties of the state operators of the optimal obstacle control problem for elliptic variational inequality. Existence, uniqueness and regularity of the optimal control problem are established. In addition, the approximation of the optimal obstacle problem is also studied.

  17. Inverse problems of geophysics

    International Nuclear Information System (INIS)

    This report gives an overview and the mathematical formulation of geophysical inverse problems. General principles of statistical estimation are explained. The maximum likelihood and least square fit methods, the Backus-Gilbert method and general approaches for solving inverse problems are discussed. General formulations of linearized inverse problems, singular value decomposition and properties of pseudo-inverse solutions are given

  18. Melamine: problems in obstetrics.

    Science.gov (United States)

    Wiwanitkit, Viroj

    2009-09-01

    Emerging problem of melamine contamination in milk and dairy products from Asia is a global problem. There are emerging questions on the adverse effect and toxicity of melamine. Acute renal failure due to acute melamine intoxication is reported. In this paper, the author will briefly discuss on the problem of melamine in obstetrics. PMID:19148659

  19. The problem of simultaneity

    Science.gov (United States)

    Marx, G.

    Drake's formula for the possible number of independent civilizations in the Galaxy is discussed in the light of several new hypotheses (e.g., Lovelock's Gaia hypothesis). Emphasis is placed on ways to overcome the time problem, i.e., the problem of how to communicate with civilizations that may arise in the future. Electronic, nucleonic, and bionic approaches to this problem are discussed.

  20. [Doctors' alcohol problems].

    Science.gov (United States)

    Florkowski, Antoni; Gruszczyński, Wojciech; Gałecki, Piotr; Szubert, Sławomir; Klus, Marek; Zboralski, Krzysztof

    2008-01-01

    An overusing and an addiction to alcoholic drinks are important problems in a medical society. The studies made in the United States had documented that about 8-12% doctors were addicted to alcohol. In many cases the doctors are able to keep their problem as a secret and their activity is satisfied up to the moment when a decrease is noticed. Some factors--such as a high level of stress--predispose doctors to alcoholic problems especially surgeons. Alcohol problems should be identified as early as possible, and therapy ought to be given as well. There is no reason to hide the problem. PMID:19025048

  1. Path Problems in Networks

    CERN Document Server

    Baras, John

    2010-01-01

    The algebraic path problem is a generalization of the shortest path problem in graphs. Various instances of this abstract problem have appeared in the literature, and similar solutions have been independently discovered and rediscovered. The repeated appearance of a problem is evidence of its relevance. This book aims to help current and future researchers add this powerful tool to their arsenal, so that they can easily identify and use it in their own work. Path problems in networks can be conceptually divided into two parts: A distillation of the extensive theory behind the algebraic path pr

  2. Internal Percolation Problem

    OpenAIRE

    Bezsudnov, I.; Snarskii, A.

    2008-01-01

    Introduced and investigated new kind of percolation problem - so called internal percolation problem (IP). In usual percolation problem current flows from top to bottom of the system and here it can be called as external percolation problem (EP) despite of the IP case when voltage is applied to the system through bars which are inside of the hole in system. EP problem has two major parameters: M size of system and a0 size of inclusion, lattice size etc. IP holds one more parameter the size of...

  3. CSNI LOCA standard problems

    International Nuclear Information System (INIS)

    In the 3. meeting of the CSNI Working Group on ECCS (August 1976), several countries expressed views on the scope of the Standard Problem programme and how often Standard Problems should be performed. Based on discussions expressed during the meeting and on some opinions, several recommendations have been made. They are presented here, divided into five sections: Objectives of CSNI Standard Problems; Proposals for New CSNI Standard Problems; Specifications for Standard Problem Analysis; Reporting of Results from CSNI Standard Problem Exercises; Calculated Results and Experimental Data Comparison Report. Section I discusses the purpose for doing Standard Problems, and the other four sections discuss the different documents that should be prepared in support of the programme. Each of these four sections attempts to outline specifications for the content of the documents

  4. Matrix interdiction problem

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory

    2010-01-01

    In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

  5. Semidefinite linear complementarity problems

    International Nuclear Information System (INIS)

    Semidefinite linear complementarity problems arise by discretization of variational inequalities describing e.g. elastic contact problems, free boundary value problems etc. In the present paper linear complementarity problems are introduced and the theory as well as the numerical treatment of them are described. In the special case of semidefinite linear complementarity problems a numerical method is presented which combines the advantages of elimination and iteration methods without suffering from their drawbacks. This new method has very attractive properties since it has a high degree of invariance with respect to the representation of the set of all feasible solutions of a linear complementarity problem by linear inequalities. By means of some practical applications the properties of the new method are demonstrated. (orig.)

  6. Convergence of Optimization Problems

    Directory of Open Access Journals (Sweden)

    K. Jeyalakshmi

    2012-03-01

    Full Text Available In this paper we consider a general optimization problem (OP and study the convergence and approximation of optimal values and optimal solutions to changes in the cost function and the set of feasible solutions. We consider the convergence optimization problems under the familiar notion of uniform convergence. We do not assume the convexity of the functions involved. Instead we consider a class of functions whose directional derivatives are convex. They are known as locally convex functions or following Craven and Mond nearly convex functions. We given necessary preliminaries and we prove that a sequence of locally convex optimization problems converge to a locally convex problem. We also prove that uniform convergence of locally convex optimization problems implies epi-graph convergence of the problems. Even though for simplicity we have taken locally convex functions, the results given here can be proved for locally Lipchitz functions also.

  7. Hidden Symmetry Subgroup Problems

    CERN Document Server

    Decker, Thomas; Santha, Miklos; Wocjan, Pawel

    2011-01-01

    We advocate a new approach of addressing hidden structure problems and finding efficient quantum algorithms. We introduce and investigate the Hidden Symmetry Subgroup Problem (HSSP), which is a generalization of the well-studied Hidden Subgroup Problem (HSP). Given a group acting on a set and an oracle whose level sets define a partition of the set, the task is to recover the subgroup of symmetries of this partition inside the group. The HSSP provides a unifying framework that, besides the HSP, encompasses a wide range of algebraic oracle problems, including quadratic hidden polynomial problems. While the HSSP can have provably exponential quantum query complexity, we obtain efficient quantum algorithms for various interesting cases. To achieve this, we present a general method for reducing the HSSP to the HSP, which works efficiently in several cases related to symmetries of polynomials. The HSSP therefore connects in a rather surprising way certain hidden polynomial problems with the HSP. Using this connect...

  8. Group Problem Solving

    CERN Document Server

    Laughlin, Patrick R

    2011-01-01

    Experimental research by social and cognitive psychologists has established that cooperative groups solve a wide range of problems better than individuals. Cooperative problem solving groups of scientific researchers, auditors, financial analysts, air crash investigators, and forensic art experts are increasingly important in our complex and interdependent society. This comprehensive textbook--the first of its kind in decades--presents important theories and experimental research about group problem solving. The book focuses on tasks that have demonstrably correct solutions within mathematical

  9. Inverse Quadratic Transportation Problem

    OpenAIRE

    Jalilzadeh, Afrooz; Hamedani, Erfan Yazdandoost

    2014-01-01

    Many research has been conducted about quadratic programming and inverse optimization. In this paper we present the combination aspect of these subjects, applying on transportation problem. First, we obtain the inverse form of quadratic tranportation problem under $L_1$ norm by using duality as well as introducing the optimal value. Then, we do the same process for inverse quadratic transportation problem (IQTP) under $L_\\infty$ norm.

  10. The Gamification Design Problem

    OpenAIRE

    Meder, Michael; Jain, Brijnesh-Johannes

    2014-01-01

    Under the assumptions that (i) gamification consists of various types of users that experience game design elements differently; and (ii) gamification is deployed in order to achieve some goal in the broadest sense, we pose the gamification problem as that of assigning each user a game design element that maximizes their expected contribution in order to achieve that goal. We show that this problem reduces to a statistical learning problem and suggest matrix factorization as one solution when...

  11. Numerical problems in physics

    CERN Document Server

    Singh, Devraj

    2015-01-01

    Numerical Problems in Physics, Volume 1 is intended to serve the need of the students pursuing graduate and post graduate courses in universities with Physics and Materials Science as subject including those appearing in engineering, medical, and civil services entrance examinations. KEY FEATURES: * 29 chapters on Optics, Wave & Oscillations, Electromagnetic Field Theory, Solid State Physics & Modern Physics * 540 solved numerical problems of various universities and ompetitive examinations * 523 multiple choice questions for quick and clear understanding of subject matter * 567 unsolved numerical problems for grasping concepts of the various topic in Physics * 49 Figures for understanding problems and concept

  12. Shielding benchmark problems, (2)

    International Nuclear Information System (INIS)

    Shielding benchmark problems prepared by Working Group of Assessment of Shielding Experiments in the Research Committee on Shielding Design in the Atomic Energy Society of Japan were compiled by Shielding Laboratory in Japan Atomic Energy Research Institute. Fourteen shielding benchmark problems are presented newly in addition to twenty-one problems proposed already, for evaluating the calculational algorithm and accuracy of computer codes based on discrete ordinates method and Monte Carlo method and for evaluating the nuclear data used in codes. The present benchmark problems are principally for investigating the backscattering and the streaming of neutrons and gamma rays in two- and three-dimensional configurations. (author)

  13. The Target Visitation Problem

    OpenAIRE

    Hildenbrandt, Achim

    2015-01-01

    The thesis considers the target visitation problem, a combinatorial optimization problem, which merges the classical traveling salesman problem with the linear ordering problem. In more detail, we are looking for a tour which visits a set of targets and which is optimal with respect to two different aspects: On the one hand, we have given a travel cost from each target to every other. On the other hand, we have preference values which tell us how much we would like to visit one target before ...

  14. A Stochastic Employment Problem

    Science.gov (United States)

    Wu, Teng

    2013-01-01

    The Stochastic Employment Problem(SEP) is a variation of the Stochastic Assignment Problem which analyzes the scenario that one assigns balls into boxes. Balls arrive sequentially with each one having a binary vector X = (X[subscript 1], X[subscript 2],...,X[subscript n]) attached, with the interpretation being that if X[subscript i] = 1 the ball…

  15. Hip Problems in Infants

    Science.gov (United States)

    ... problems that can lead to dislocation of the hip bones. This is also called dysplasia (say: "diss-play-see-uh"). This means that ... problems later in life? Source Screening for Developmental Dysplasia of the Hip by LM French, M.D., and FR Dietz, ...

  16. Heat exchangers: operation problems

    International Nuclear Information System (INIS)

    The main operation problems for heat exchangers are fouling, corrosion, vibrations and mechanical resistance. Fouling and corrosion lead to an over dimensioning, energy consumption increase, corroded pieces change, shutdown costs. Vibrations are taken in account during the dimensioning phase of the heat exchangers. Mechanical resistance problems are, for the classical ones, described in regulation texts. (A.B.). 5 figs., 4 tabs

  17. Convex Congestion Network Problems

    OpenAIRE

    2004-01-01

    This paper analyzes convex congestion network problems.It is shown that for network problems with convex congestion costs, an algorithm based on a shortest path algorithm, can be used to find an optimal network for any coalition. Furthermore an easy way of determining if a given network is optimal is provided.

  18. Reconfigurable layout problem

    NARCIS (Netherlands)

    Meng, G.; Heragu, S.S.; Zijm, H.

    2004-01-01

    This paper addresses the reconfigurable layout problem, which differs from traditional, robust and dynamic layout problems mainly in two aspects: first, it assumes that production data are available only for the current and upcoming production period. Second, it considers queuing performance measure

  19. Simon on problem solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    2006-01-01

    general approach to problem solving. We apply these Simonian ideas to organisational issues, specifically new organisational forms. Specifically, Simonian ideas allow us to develop a morphology of new organisational forms and to point to some design problems that characterise these forms....

  20. The Graffiti Problem

    OpenAIRE

    JS Armstrong

    2004-01-01

    Graffiti is regarded by many as a blight on our cities because it contributes to visual pollution. City governments spend vast sums in an effort to clean the ubiquitous graffiti from urban walls. I suggest that the “cleansing strategy” is an expensive, ineffective way of dealing with the problem; well-known management techniques can solve the problem more efficiently.

  1. Teaching through Problem Solving

    Science.gov (United States)

    Fi, Cos D.; Degner, Katherine M.

    2012-01-01

    Teaching through Problem Solving (TtPS) is an effective way to teach mathematics "for" understanding. It also provides students with a way to learn mathematics "with" understanding. In this article, the authors present a definition of what it means to teach through problem solving. They also describe a professional development vignette that…

  2. Mathematical Problem Solving.

    Science.gov (United States)

    Mayer, Richard E.

    This chapter examines research on the cognitive processes involved in mathematical problem solving. The introduction includes definitions of key terms and a summary of four cognitive processes used in mathematical problem solving: (1) translating; (2) integrating; (3) planning; and (4) executing. Examples are then provided and exemplary research…

  3. The generalized Tailor Problem

    NARCIS (Netherlands)

    Roerdink, J.B.T.M.; Maragos, P; Schafer, RW; Butt, MA

    1996-01-01

    The so-called 'Tailor Problem' concerns putting a number of sets within another set by translation, such that the translated sets do not overlap. In this paper we consider a generalization of this problem in which also rotations of the sets are allowed.

  4. Problems in baryon spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Capstick, S. [Florida State Univ., Tallahassee, FL (United States)

    1994-04-01

    Current issues and problems in the physics of ground- and excited-state baryons are considered, and are classified into those which should be resolved by CEBAF in its present form, and those which may require CEBAF to undergo an energy upgrade to 8 GeV or more. Recent theoretical developments designed to address these problems are outlined.

  5. Dynamical inverse problems

    CERN Document Server

    Gladwell, Graham ML

    2011-01-01

    The papers in this volume present an overview of the general aspects and practical applications of dynamic inverse methods, through the interaction of several topics, ranging from classical and advanced inverse problems in vibration, isospectral systems, dynamic methods for structural identification, active vibration control and damage detection, imaging shear stiffness in biological tissues, wave propagation, to computational and experimental aspects relevant for engineering problems.

  6. Medical problems affecting musicians.

    OpenAIRE

    Potter, P J; Jones, I C

    1995-01-01

    The physical demands of performing on musical instruments can cause pain, sensory loss, and lack of coordination. Five cases illustrate common problems. Knowledge of the interaction between the technique of playing the instrument and the particular musician can help physicians diagnose and resolve problems.

  7. Problem-Based Learning

    Science.gov (United States)

    Allen, Deborah E.; Donham, Richard S.; Bernhardt, Stephen A.

    2011-01-01

    In problem-based learning (PBL), students working in collaborative groups learn by resolving complex, realistic problems under the guidance of faculty. There is some evidence of PBL effectiveness in medical school settings where it began, and there are numerous accounts of PBL implementation in various undergraduate contexts, replete with…

  8. GREECE--SELECTED PROBLEMS.

    Science.gov (United States)

    MARTONFFY, ANDREA PONTECORVO; AND OTHERS

    A CURRICULUM GUIDE IS PRESENTED FOR A 10-WEEK STUDY OF ANCIENT GREEK CIVILIZATION AT THE 10TH-GRADE LEVEL. TEACHING MATERIALS FOR THE UNIT INCLUDE (1) PRIMARY AND SECONDARY SOURCES DEALING WITH THE PERIOD FROM THE BRONZE AGE THROUGH THE HELLENISTIC PERIOD, (2) GEOGRAPHY PROBLEMS, AND (3) CULTURAL MODEL PROBLEM EXERCISES. THOSE CONCEPTS WITH WHICH…

  9. Problems in equilibrium theory

    CERN Document Server

    Aliprantis, Charalambos D

    1996-01-01

    In studying General Equilibrium Theory the student must master first the theory and then apply it to solve problems. At the graduate level there is no book devoted exclusively to teaching problem solving. This book teaches for the first time the basic methods of proof and problem solving in General Equilibrium Theory. The problems cover the entire spectrum of difficulty; some are routine, some require a good grasp of the material involved, and some are exceptionally challenging. The book presents complete solutions to two hundred problems. In searching for the basic required techniques, the student will find a wealth of new material incorporated into the solutions. The student is challenged to produce solutions which are different from the ones presented in the book.

  10. The Guderley problem revisited

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, Scott D [Los Alamos National Laboratory; Kamm, James R [Los Alamos National Laboratory; Bolstad, John H [NON LANL

    2009-01-01

    The self-similar converging-diverging shock wave problem introduced by Guderley in 1942 has been the source of numerous investigations since its publication. In this paper, we review the simplifications and group invariance properties that lead to a self-similar formulation of this problem from the compressible flow equations for a polytropic gas. The complete solution to the self-similar problem reduces to two coupled nonlinear eigenvalue problems: the eigenvalue of the first is the so-called similarity exponent for the converging flow, and that of the second is a trajectory multiplier for the diverging regime. We provide a clear exposition concerning the reflected shock configuration. Additionally, we introduce a new approximation for the similarity exponent, which we compare with other estimates and numerically computed values. Lastly, we use the Guderley problem as the basis of a quantitative verification analysis of a cell-centered, finite volume, Eulerian compressible flow algorithm.

  11. Structural Identification Problem

    Directory of Open Access Journals (Sweden)

    Suvorov Aleksei

    2016-01-01

    Full Text Available The identification problem of the existing structures though the Quasi-Newton and its modification, Trust region algorithms is discussed. For the structural problems, which could be represented by means of the mathematical modelling of the finite element code discussed method is extremely useful. The nonlinear minimization problem of the L2 norm for the structures with linear elastic behaviour is solved by using of the Optimization Toolbox of Matlab. The direct and inverse procedures for the composition of the desired function to minimize are illustrated for the spatial 3D truss structure as well as for the problem of plane finite elements. The truss identification problem is solved with 2 and 3 unknown parameters in order to compare the computational efforts and for the graphical purposes. The particular commands of the Matlab codes are present in this paper.

  12. The interval ordering problem

    CERN Document Server

    Dürr, Christoph; Spieksma, Frits C R; Nobibon, Fabrice Talla; Woeginger, Gerhard J

    2011-01-01

    For a given set of intervals on the real line, we consider the problem of ordering the intervals with the goal of minimizing an objective function that depends on the exposed interval pieces (that is, the pieces that are not covered by earlier intervals in the ordering). This problem is motivated by an application in molecular biology that concerns the determination of the structure of the backbone of a protein. We present polynomial-time algorithms for several natural special cases of the problem that cover the situation where the interval boundaries are agreeably ordered and the situation where the interval set is laminar. Also the bottleneck variant of the problem is shown to be solvable in polynomial time. Finally we prove that the general problem is NP-hard, and that the existence of a constant-factor-approximation algorithm is unlikely.

  13. Problem Solving and Learning

    CERN Document Server

    Singh, Chandralekha

    2016-01-01

    One finding of cognitive research is that people do not automatically acquire usable knowledge by spending lots of time on task. Because students' knowledge hierarchy is more fragmented, "knowledge chunks" are smaller than those of experts. The limited capacity of short term memory makes the cognitive load high during problem solving tasks, leaving few cognitive resources available for metacognition. The abstract nature of the laws of physics and the chain of reasoning required to draw meaningful inferences makes these issues critical. In order to help students, it is crucial to consider the difficulty of a problem from the perspective of students. We are developing and evaluating interactive problem-solving tutorials to help students in the introductory physics courses learn effective problem-solving strategies while solidifying physics concepts. The self-paced tutorials can provide guidance and support for a variety of problem solving techniques, and opportunity for knowledge and skill acquisition.

  14. The Interaction Programming Problem

    Institute of Scientific and Technical Information of China (English)

    LI Rong-sheng; CHENG Ying

    2001-01-01

    Based upon the research to the economic equilibrium problems, we present a kind of new mathematical programming problem-interaction programming problem (abbreviated by IPP). The IPP is composed of two or multiple parametric programming problems which is interrelated with each other. The IPP reflects the equality and mutual benefit relationship between two (or among multiple) economic planners in an economic system. In essence, the IPP is similar to the generalized Nash equilibria (GNE) game which has been given several names in the literature: social equilibria games, pseudo-Nash equilibria games, and equilibrium programming problems. In this paper, we establish the mathematical model and some basic concepts to the IPP. We investigate the structure and the properties of the IPP. We also give a necessary and sufficient conditions for the existence of the equilibrium points to a kind of linear IPP.

  15. Problems of energy supply. Probleme der Energieversorgung

    Energy Technology Data Exchange (ETDEWEB)

    Frank, W.

    1983-01-01

    Political education is to enable judgement of present-day questions. This requires knowledge of the essential facts in the field of energy supply. The brochure on hand is meant to make it easier for the reader to put forward his own arguments. The reader is to see that it is due to the many motives determining energy policy which aggravate an understanding about ways of solving problems of energy supply. This brochure is designed to enhance political education by giving a survey of tasks in energy policy to be solved on an international level and in Austria.

  16. Puzzles, Pastimes, Problems.

    Science.gov (United States)

    Eperson, D. B.

    1985-01-01

    Presents six mathematical problems (with answers) which focus on: (1) chess moves; (2) patterned numbers; (3) quadratics with rational roots; (4) number puzzles; (5) Euclidean geometry; and (6) Carrollian word puzzles. (JN)

  17. What Are Knee Problems?

    Science.gov (United States)

    ... Health Information Basics for You and Your Family Sports Injuries, Handout on Health Health Information Knee Problems Find ... for a long time. This sometimes occurs in sports training. Treatment for tendon injuries and disorders includes: Rest Ice Elevation Medicines such ...

  18. Pelvic Support Problems

    Science.gov (United States)

    ... nonsurgical ways to obtain symptom relief? • What are Kegel exercises? • Can surgery correct pelvic support problems? • Glossary ... your overall health and possibly your prolapse symptoms. • Kegel exercises—These exercises strengthen the muscles that surround ...

  19. Problems sleeping during pregnancy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000559.htm Problems sleeping during pregnancy To use the sharing features on ... time sleeping well. Why is it hard to sleep during pregnancy? Your baby is growing bigger, which ...

  20. Challenging problems in geometry

    CERN Document Server

    Posamentier, Alfred S

    2012-01-01

    Collection of nearly 200 unusual problems dealing with congruence and parallelism, the Pythagorean theorem, circles, area relationships, Ptolemy and the cyclic quadrilateral, collinearity and concurrency and more. Arranged in order of difficulty. Detailed solutions.

  1. Overcoming breastfeeding problems

    Science.gov (United States)

    Plugged milk ducts; Nipple soreness when breastfeeding; Breastfeeding - overcoming problems; Let-down reflex ... Breastfeeding (nursing) your baby can be a good experience for both the mother and the baby. It ...

  2. The problem of pain.

    Science.gov (United States)

    Nicholson, Keith; Martelli, Michael F

    2004-01-01

    Pain problems, especially posttraumatic headache, are very common following head trauma. Pain may be the most significant problem, more disabling than any brain or other injuries, and interfering with aspects of cognition or other function. However, posttraumatic headache and most other chronic posttraumatic pain problems remain poorly understood. This article reviews fundamental issues that should be considered in understanding the nature of chronic pain including the distinction between acute and chronic pain; neurobiological distinctions between the lateral and medial pain system; nociceptive versus neuropathic or other central pain; sensitization effects; the widely accepted view of chronic pain as a multidimensional subjective experience involving sensory, motivational-affective and cognitive-behavioral components; the problem of mind-body dualism; the role of psychosocial factors in the onset, maintenance, exacerbation or severity of pain; plus issues of response bias and malingering. PMID:14732827

  3. Our Accountability Problems

    Science.gov (United States)

    Cunningham, Luvern L.

    1969-01-01

    Evaluation of school administrators to determine whether they are truly performing their functions adequately has presented a problem of long standing since most administrators find excuses to avoid appraisal of their performance. (CK)

  4. Diabetic Eye Problems

    Science.gov (United States)

    ... damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause of blindness ... You need a healthy retina to see clearly. Diabetic retinopathy damages the tiny blood vessels inside your ...

  5. Enuresis: A Social Problem.

    Science.gov (United States)

    McDonald, James E.

    1978-01-01

    Several theories and treatments of enuresis are described. The authors conclude that enuresis is a social problem (perhaps due to maturational lag, developmental delay or faulty learning) which requires teacher and parental tolerance and understanding. (SE)

  6. Problems in optics

    CERN Document Server

    Rousseau, Madeleine; Ter Haar, D

    1973-01-01

    This collection of problems and accompanying solutions provide the reader with a full introduction to physical optics. The subject coverage is fairly traditional, with chapters on interference and diffraction, and there is a general emphasis on spectroscopy.

  7. Problems of Chernobyl

    International Nuclear Information System (INIS)

    The collection contains scientific articles which theme is mainly directed on the solving of the problems of 'Ukryttia' safe exploitation ensuring and transformation in into an ecologically safe system and report materials of ISTC 'Shelter' works during 2000 year

  8. Common Foot Problems

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Common Foot Problems A A A Trauma, infection, skin disease, ... the sole of the front part of the foot and on the toes. Foot infections include warts; ...

  9. Creativity and Problem Solving

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2004-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving...

  10. Micronutrient problems in Korea

    International Nuclear Information System (INIS)

    Background information on the extent of micronutrient problems in connection with the low productivity paddy soils in Korea is given. Areas of research on micronutrients in which isotopes might suitably be employed are outlined

  11. Menstrual Cycle Problems

    Science.gov (United States)

    ... problem with the lining of the uterus, or OVARIAN CYSTS. See your doctor. *5. Are your periods heavier ... fullness or nausea? Yes You may have an OVARIAN CYST, or you may be PREGNANT. If you could ...

  12. [Oral problems in divers].

    Science.gov (United States)

    Scheper, W A; Lobbezoo, F; Eijkman, M A J

    2005-05-01

    Divers can have several oral problems. Firstly, problems caused by pressure changes. These are barodontalgia and odontocrexis. Barodontalgia is toothache by barotrauma. Odontocrexis is restorations coming lose or breaking or tooth fractures by expansion of air beneath restorations. Other problems can occur by cements used to fix casted restorations, by inflammations in the orofacial region, and by not yet fully healed oral wounds. Secondly, there are problems related to the diver's mouthpiece. To keep the mouthpiece in place, the mandible has to be forced in a forward position. Holding this position often and for long periods of time, may develop or aggravate temporomandibular dysfunction. Insufficient fit of the mouthpiece may induce oral mucosal lesions. Therefore, it is recommended to produce individual diver mouthpieces. It is also recommended to produce individual diver mouthpieces for complete dentures wearing divers and for divers with fixed orthodontic appliances. PMID:15932043

  13. Sleep Problems and ADHD

    OpenAIRE

    J Gordon Millichap

    2008-01-01

    The prevalence of sleep problems and their associations with quality of life (QOL), school attendance, and family impacts in children with ADHD were determined in a study at Royal Children's Hospital, University of Melbourne, Australia.

  14. Problems around 3-manifolds

    OpenAIRE

    Rubinstein, J Hyam

    2009-01-01

    This is a personal view of some problems on minimal surfaces, Ricci flow, polyhedral geometric structures, Haken 4-manifolds, contact structures and Heegaard splittings, singular incompressible surfaces after the Hamilton-Perelman revolution.

  15. The Congruence Subgroup Problem

    Indian Academy of Sciences (India)

    M S Raghunathan

    2004-11-01

    This is a short survey of the progress on the congruence subgroup problem since the sixties when the first major results on the integral unimodular groups appeared. It is aimed at the non-specialists and avoids technical details.

  16. Open problems in mathematics

    CERN Document Server

    Nash, Jr, John Forbes

    2016-01-01

    The goal in putting together this unique compilation was to present the current status of the solutions to some of the most essential open problems in pure and applied mathematics. Emphasis is also given to problems in interdisciplinary research for which mathematics plays a key role. This volume comprises highly selected contributions by some of the most eminent mathematicians in the international mathematical community on longstanding problems in very active domains of mathematical research. A joint preface by the two volume editors is followed by a personal farewell to John F. Nash, Jr. written by Michael Th. Rassias. An introduction by Mikhail Gromov highlights some of Nash’s legendary mathematical achievements. The treatment in this book includes open problems in the following fields: algebraic geometry, number theory, analysis, discrete mathematics, PDEs, differential geometry, topology, K-theory, game theory, fluid mechanics, dynamical systems and ergodic theory, cryptography, theoretical computer sc...

  17. Solving Tommy's Writing Problems.

    Science.gov (United States)

    Burdman, Debra

    1986-01-01

    The article describes an approach by which word processing helps to solve some of the writing problems of learning disabled students. Aspects considered include prewriting, drafting, revising, and completing the story. (CL)

  18. The ternary Goldbach problem

    OpenAIRE

    Helfgott, Harald Andrés

    2015-01-01

    The ternary Goldbach conjecture, or three-primes problem, states that every odd number $n$ greater than $5$ can be written as the sum of three primes. The conjecture, posed in 1742, remained unsolved until now, in spite of great progress in the twentieth century. In 2013 -- following a line of research pioneered and developed by Hardy, Littlewood and Vinogradov, among others -- the author proved the conjecture. In this, as in many other additive problems, what is at issue is really the proper...

  19. Problems encountered by tourists

    OpenAIRE

    C. Madhavi; A. Auroubindo Ganesh

    2010-01-01

    Tourism is an upcoming and fast growing industry in developing countries like India. Due to its newness in nature, there are some hurdles that the tourists face. This will affect the national economy and the growth of this industry may get affected. This paper focuses on identifying such problems and their intensity level. This also attempts to study whether there is any significant difference in the problem faced by respondents based on demographic factors. Convenient samples of 150 res...

  20. Accelerator shielding benchmark problems

    International Nuclear Information System (INIS)

    Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)

  1. The decentralized implementability problem

    OpenAIRE

    Fiaz, Shaik; Trentelman, H.L.

    2010-01-01

    This paper deals with the problems of decentralized implementability and decentralized regular implementability in the context of finite-dimensional linear differential system behaviors. Given a plant behavior with a pre-specified partition of the system variable and a desired behavior, the problem of decentralized implementability is to find a controller which is decentralized with respect to the given partition and implements (regularly) the desired behavior with respect to the plant. In th...

  2. Accelerator shielding benchmark problems

    Energy Technology Data Exchange (ETDEWEB)

    Hirayama, H.; Ban, S.; Nakamura, T. [and others

    1993-01-01

    Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author).

  3. The road coloring problem

    OpenAIRE

    Trahtman, A. N.

    2007-01-01

    The synchronizing word of deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into deterministic finite automaton possessing a synchronizing word. The road coloring problem is a problem of synchronizing coloring of directed finite strongly connected graph with constant outdegree of all its vertices if the greatest comm...

  4. PROBLEMS OF ADOLESCENCE

    OpenAIRE

    Hubble, Douglas

    1982-01-01

    Adolescence is a period of active growth and development-physical, sexual, social and emotional. There are wide normal variations between the time of onset and the attainment of full maturity. Many adolescents present few if any problems during this potentially turbulent period, and make the necessary adjustments without undue stress to themselves, their family or their friends. Problems in growth and hormonal balance, presenting as short and tall teenagers, menstrual irregularities, obesity ...

  5. The basketball problem

    Science.gov (United States)

    Schröer, H.

    In basketball there is the problem of hitting a basket at a determined distance and a determined height. The quantities that can be changed during the inclined throw are the initial velocity and the angle of throw. At first we neglect the air resistance. Then we treat the same problem in a medium (liquid, gas) with constant density. We obtain two differential equations. Then we view special cases of the retarding force. There is an english and a german edition.

  6. Problem Based Learnig

    OpenAIRE

    Kolmos, Anette; Kuru, Selahattin; Hansen, Hans; Eskil, Taner; Podesta, Luca; Fink, Flemming; Graaff, Erik de; Uwe Wolff, Jan; Soylu, Ahmet

    2007-01-01

    This report discuss Problem-Based and Project-Based Learning (PBL) as an approach to meeting the demand for the educational requirements of the next generation engineering graduates. The report is prepared as the final report of the Special Interest Group (SIG) B5 of the Erasmus Thematic Network Project TREE (Teaching and Research in Engineering Education) on Problem- Based and Project-Based Learning. In engineering education there is a shift in emphasis from professional skill...

  7. Steiner Forest Orientation Problems

    CERN Document Server

    Cygan, Marek; Nutov, Zeev

    2011-01-01

    We consider connectivity problems with orientation constraints. Given a directed graph $D$ and a collection of ordered node pairs $P$ let $P[D]={(u,v) \\in P: D contains a uv-paths}$. In the Steiner Forest Orientation problem we are given an undirected graph $G=(V,E)$ with edge-costs and a set $P \\subseteq V \\times V$ of ordered node pairs. The goal is to find a minimum-cost subgraph $H$ of $G$ and an orientation $D$ of $H$ such that $P[D]=P$. We give a 4-approximation algorithm for this problem. In the Maximum Pairs Orientation problem we are given a graph $G$ and a multi-collection of ordered node pairs $P$ on $V$. The goal is to find an orientation $D$ of $G$ such that $|P[D]|$ is maximum. Generalizing the result of Arkin and Hassin for $|P|=2$, we will show that for a mixed graph $G$ (that may have both directed an undirected edges), one can decide in $n^{O(|P|)}$ time whether $G$ has an orientation $D$ with $P[D]=P$ (for undirected graphs this problem admits a polynomial time algorithm for any $P$, but it...

  8. The Steiner tree problem

    CERN Document Server

    Hwang, FK; Winter, P

    1992-01-01

    The Steiner problem asks for a shortest network which spans a given set of points. Minimum spanning networks have been well-studied when all connections are required to be between the given points. The novelty of the Steiner tree problem is that new auxiliary points can be introduced between the original points so that a spanning network of all the points will be shorter than otherwise possible. These new points are called Steiner points - locating them has proved problematic and research has diverged along many different avenues. This volume is devoted to the assimilation of the rich field of intriguing analyses and the consolidation of the fragments. A section has been given to each of the three major areas of interest which have emerged. The first concerns the Euclidean Steiner Problem, historically the original Steiner tree problem proposed by Jarník and Kössler in 1934. The second deals with the Steiner Problem in Networks, which was propounded independently by Hakimi and Levin and has enjoyed the most...

  9. Computational problems in engineering

    CERN Document Server

    Mladenov, Valeri

    2014-01-01

    This book provides readers with modern computational techniques for solving variety of problems from electrical, mechanical, civil and chemical engineering. Mathematical methods are presented in a unified manner, so they can be applied consistently to problems in applied electromagnetics, strength of materials, fluid mechanics, heat and mass transfer, environmental engineering, biomedical engineering, signal processing, automatic control and more.   • Features contributions from distinguished researchers on significant aspects of current numerical methods and computational mathematics; • Presents actual results and innovative methods that provide numerical solutions, while minimizing computing times; • Includes new and advanced methods and modern variations of known techniques that can solve difficult scientific problems efficiently.  

  10. Dirac's Quantum Phase Problem

    CERN Document Server

    Sperling, J

    2009-01-01

    In 1927 the great physicist Paul A. M. Dirac failed to provide a consistent quantum description of the phase of a radiation field. Only one year later, he developed the famous Dirac theory of the electron, which led to the anti-particle -- the positron. We show that the reason for Dirac's failure with the phase problem bears a striking resemblance to his ingenious insight into the nature of the electron. For a correct quantum description of the phase of a radiation field it is necessary to take the polarisation into account. Similarly to the introduction of the anti-particle of the electron, the inclusion of the second polarisation resolves the inconsistency of the quantum phase problem. This also leads to new insight into the quantum measurement problem of time.

  11. Problem Based Learning

    DEFF Research Database (Denmark)

    de Graaff, Erik; Guerra, Aida

    Problem-Based Learning (PBL) is an innovative method to organize the learning process in such a way that the students actively engage in finding answers by themselves. During the past 40 years PBL has evolved and diversified resulting in a multitude in variations in models and practices. However...... model and in general problem based and project based learning. We apply the principle of teach as you preach. The poster aims to outline the visitors’ workshop programme showing the results of some recent evaluations......., the key principles remain the same everywhere. Graaff & Kolmos (2003) identify the main PBL principles as follows: 1. Problem orientation 2. Project organization through teams or group work 3. Participant-directed 4. Experiental learning 5. Activity-based learning 6. Interdisciplinary learning and 7...

  12. Problems in quantum mechanics

    CERN Document Server

    Kogan, VI; Gersch, Harold

    2011-01-01

    Written by a pair of distinguished Soviet mathematicians, this compilation presents 160 lucidly expressed problems in nonrelativistic quantum mechanics plus completely worked-out solutions. Some were drawn from the authors' courses at the Moscow Institute of Engineering, but most were prepared especially for this book. A high-level supplement rather than a primary text, it constitutes a masterful complement to advanced undergraduate and graduate texts and courses in quantum mechanics.The mathematics employed in the proofs of the problems-asymptotic expansions of functions, Green's functions, u

  13. Problem Based Game Design

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2011-01-01

    At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games....

  14. Another thorny problem

    Directory of Open Access Journals (Sweden)

    Calvert Watkins

    2015-09-01

    Full Text Available Students of Indo-European are beset by thorns, from the third letter of the Runic alphabet through the Hieroglyphic Luvian excrescent +ra/i to Brugmann's 'Notbehelf' *kp of such cognate sets as the word for 'bear'; see J. Schindler, "A thorny problem," Die Sprache 23 (1977 25ff. Our problem is simpler, however sticky; it is a pleasure to offer a suggestion for its solution to Professor Bojan Čop, who has so enriched Hittite studies over so many years.

  15. Problems encountered by tourists

    Directory of Open Access Journals (Sweden)

    C. Madhavi

    2010-10-01

    Full Text Available Tourism is an upcoming and fast growing industry in developing countries like India. Due to its newness in nature, there are some hurdles that the tourists face. This will affect the national economy and the growth of this industry may get affected. This paper focuses on identifying such problems and their intensity level. This also attempts to study whether there is any significant difference in the problem faced by respondents based on demographic factors. Convenient samples of 150 respondents have been selected for this study. Suitable statistical tools such as Cluster analysis, Chi-square test and multiple regression are used.

  16. Calculus problems and solutions

    CERN Document Server

    Ginzburg, A

    2011-01-01

    Ideal for self-instruction as well as for classroom use, this text helps students improve their understanding and problem-solving skills in analysis, analytic geometry, and higher algebra. More than 1,200 problems appear in the text, with concise explanations of the basic notions and theorems to be used in their solution. Many are followed by complete answers; solutions for the others appear at the end of the book. Topics include sequences, functions of a single variable, limit of a function, differential calculus for functions of a single variable, fundamental theorems and applications of dif

  17. Electric circuits problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

    Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of electric circuits currently av

  18. Electrical problems committee report

    International Nuclear Information System (INIS)

    This document is the report of the committee appointed to review the experience of the MFE Program with electrical equipment and to suggest actions to minimize future problems. The committee observed that the electrical problems that have occurred could be traced not to misapplication of project and engineering technical principles, but to lack of application of project and engineering management principles. The report is structured so that the first four sections: Introduction, Findings, Recommendations, and Immediate Recommended Actions, can be used as an executive summary. The discussion section and attachments contain further detail

  19. Matrices in Engineering Problems

    CERN Document Server

    Tobias, Marvin

    2011-01-01

    This book is intended as an undergraduate text introducing matrix methods as they relate to engineering problems. It begins with the fundamentals of mathematics of matrices and determinants. Matrix inversion is discussed, with an introduction of the well known reduction methods. Equation sets are viewed as vector transformations, and the conditions of their solvability are explored. Orthogonal matrices are introduced with examples showing application to many problems requiring three dimensional thinking. The angular velocity matrix is shown to emerge from the differentiation of the 3-D orthogo

  20. The Quantum Falsifiability Problem

    OpenAIRE

    Dall'Arno, Michele; Brandsen, Sarah; Buscemi, Francesco

    2016-01-01

    A hypothesis about a physical device is falsified as soon as an experiment collects data that is not compatible with it. Here we construct a general framework to study the quantum falsifiability problem, namely, the problem of deciding whether a given input-output probability distribution (i.e., the data) can be obtained from a given candidate quantum channel (i.e., the hypothesis) or not. Our approach is completely device-independent, as the piece of experimental evidence -- the input-output...

  1. Advanced calculus problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

    Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of advanced calculus currently av

  2. Classic Problems of Probability

    CERN Document Server

    Gorroochurn, Prakash

    2012-01-01

    "A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin

  3. Problems over Information Systems

    KAUST Repository

    Chikalov, Igor

    2011-01-01

    The problems of estimation of the minimum average time complexity of decision trees and design of efficient algorithms are complex in general case. The upper bounds described in Chap. 2.4.3 can not be applied directly due to large computational complexity of the parameter M(z). Under reasonable assumptions about the relation of P and NP, there are no polynomial time algorithms with good approximation ratio [12, 32]. One of the possible solutions is to consider particular classes of problems and improve the existing results using characteristics of the considered classes. © Springer-Verlag Berlin Heidelberg 2011.

  4. The Urinal Problem

    Science.gov (United States)

    Kranakis, Evangelos; Krizanc, Danny

    A man walks into a men's room and observes n empty urinals. Which urinal should he pick so as to maximize his chances of maintaining privacy, i.e., minimize the chance that someone will occupy a urinal beside him? In this paper, we attempt to answer this question under a variety of models for standard men's room behavior. Our results suggest that for the most part one should probably choose the urinal furthest from the door (with some interesting exceptions). We also suggest a number of variations on the problem that lead to many open problems.

  5. Assessing the Quality of Problems in Problem-Based Learning

    Science.gov (United States)

    Sockalingam, Nachamma; Rotgans, Jerome; Schmidt, Henk

    2012-01-01

    This study evaluated the construct validity and reliability of a newly devised 32-item problem quality rating scale intended to measure the quality of problems in problem-based learning. The rating scale measured the following five characteristics of problems: the extent to which the problem (1) leads to learning objectives, (2) is familiar, (3)…

  6. Additivity in bankruptcy problems and in allocation problems

    OpenAIRE

    Gustavo Bergantiños; Luciano Méndez-Naya

    2001-01-01

    We study the property of additivity in bankruptcy problems and in allocation problems. In bankruptcy problems we use this property to characterize the Talmudic rule proposed by Rabbi Ibn Ezra. Moreover we generalize this rule to every bankruptcy problem. Again, using additivity we characterize the rights egalitarian solution in allocation problems.

  7. A Survey of Transportation Problems

    OpenAIRE

    2014-01-01

    This paper aims at being a guide to understand the different types of transportation problems by presenting a survey of mathematical models and algorithms used to solve different types of transportation modes (ship, plane, train, bus, truck, Motorcycle, Cars, and others) by air, water, space, cables, tubes, and road. Some problems are as follows: bus scheduling problem, delivery problem, combining truck trip problem, open vehicle routing problem, helicopter routing problem, truck loading p...

  8. Problems with Smell

    Science.gov (United States)

    ... types of accidents in order of frequency involve cooking eating or drinking spoiled foods or toxic substances failing to detect gas leaks or fires If you think you have a problem with your sense of smell, see your doctor. home | health topics A-Z | videos A-Z | training | ...

  9. Microbiological problems in radiosterilization

    International Nuclear Information System (INIS)

    Criteria for medical materials sterilization from the view point of sanitary-hygiene aspects have been broadly discussed. More important problems have been pointed out as follows: assurance of proper hygienic conditions in production, pharmacopoeia rules and regulations compliance, physico-chemical and biological investigations of each new material and product. 19 refs, 4 figs, 3 tabs

  10. Human Population Problems

    Science.gov (United States)

    Emmel, Thomas C.; Sligh, Michael M.

    1970-01-01

    Asserts that overpopulation is the most pressing world problem. Topics discussed include population control in primitive societies, population growth and control in modern societies, methods of motivational population control, consequences of no population control, and mass famines during the 1970's in underdeveloped countries. Cities 33…

  11. Symmetries of Spectral Problems

    Science.gov (United States)

    Shabat, A.

    Deriving abelian KdV and NLS hierarchies, we describe non-abelian symmetries and "pre-Lax" elementary approach to Lax pairs. Discrete symmetries of spectral problems are considered in Sect. 4.2. Here we prove Darboux classical theorem and discuss a modern theory of dressing chains.

  12. Problem Solving with Patents

    Science.gov (United States)

    Moore, Jerilou; Sumrall, William J.

    2008-01-01

    Exploring our patent system is a great way to engage students in creative problem solving. As a result, the authors designed a teaching unit that uses the study of patents to explore one avenue in which scientists and engineers do science. Specifically, through the development of an idea, students learn how science and technology are connected.…

  13. Types of Learning Problems

    Science.gov (United States)

    ... of time in their own world—even for teenagers—but they’re often lonely and want to make friends. The problem is, they’re not sure how to act in social settings. Between that and their eccentricities, they may become victims of teasing and bullying . Parents of a child with AS, or any ...

  14. The CP Violation Problem

    CERN Document Server

    Naboulsi, R

    2003-01-01

    A review on CP violation in the B and K mesons systems is given, which, we hope may familiarize new Belle members in the basic ingredients of this topic, which is one of the most challenging problems of experimental high energy physics.

  15. Health Problems at School

    Science.gov (United States)

    ... of a lack of health-care providers, an absence of insurance, or transportation problems. The American Academy of Pediatrics believes that all children deserve a "medical home" and supports the implementation of school-based clinics, especially in areas where children do ...

  16. LEXICOGRAPHICAL PROBLEMS IN PASHTO.

    Science.gov (United States)

    CHAVARRIS-AGUILAR, O.L.; PENZL, HERBERT

    PROBLEMS IN DEVELOPING SUITABLE DICTIONARIES OF PASHTO WERE REPORTED. PASHTO WAS DESCRIBED AS A MEMBER OF THE IRANIAN BRANCH OF THE INDO-EUROPEAN LANGUAGES SPOKEN IN EASTERN AND SOUTHERN AFGHANISTAN AND IN NORTHEASTERN PAKISTAN. FIVE TOPICS DEALING WITH THE PASHTO LANGUAGE WERE DISCUSSED--(1) STATISTICS, (2) WRITTEN CORPUS AND LEXICAL STUDIES, (3)…

  17. Thermodynamics with Design Problems.

    Science.gov (United States)

    Cilento, E. V.; Sears, J. T.

    1983-01-01

    Discusses how basic thermodynamics concepts are integrated with design problems. Includes course goals, instructional strategies, and major advantages/disadvantages of the integrated design approach. Advantages include making subject more concrete, emphasizing interrelation of variables, and reinforcing concepts by use in design analysis; whereas…

  18. Benchmark problem proposal

    International Nuclear Information System (INIS)

    The meeting of the Radiation Energy Spectra Unfolding Workshop organized by the Radiation Shielding Information Center is discussed. The plans of the unfolding code benchmarking effort to establish methods of standardization for both the few channel neutron and many channel gamma-ray and neutron spectroscopy problems are presented

  19. Security problems at Vivitron

    International Nuclear Information System (INIS)

    The risks of accidents and the safety actions concerning the components and the staff protection at Vivitron are analyzed. The risks induced by the utilization of SF6 is mainly asphyxia. The sealing defects on the gas storage devices and gas leaking inside Vivitron are considered. The safety actions and devices are summarized. Radiation protection problems are also discussed

  20. Environmental Health Problems.

    Science.gov (United States)

    Environmental Health Service (DHEW/PHS), Rockville, MD.

    Aimed at a society which is forced to make decisions relative to their total environment, this pamphlet discusses a few of the problems associated with restoring and maintaining an environmental relationship conducive to the health and well-being of man. The topics covered include: air pollution, noise, solid waste, the urban environment, drinking…

  1. The passive polymer problem

    CERN Document Server

    Wiese, K J

    1999-01-01

    In this article, we introduce a generalization of the diffusive motion of point-particles in a turbulent convective flow with given correlations to a polymer or membrane. In analogy to the passive scalar problem we call this the passive polymer or membrane problem. We shall focus on the expansion about the marginal limit of velocity-velocity correlations which are uncorrelated in time and grow with the distance x as |x|^epsilon, and epsilon small. This relation gets modified for polymers and membranes (the marginal advecting flow has correlations which are shorter ranged.) The construction is done in three steps: First, we reconsider the treatment of the passive scalar problem using the most convenient treatment via field theory and renormalization group. We explicitly show why IR-divergences and thus the system-size appear in physical observables. In a second step, we reformulate the problem in terms of a Langevin equation. This is not only interesting in its own, but also gives an efficient algorithm to det...

  2. Screening for Breast Problems

    Science.gov (United States)

    ... a clinical breast exam done? • What is breast self-awareness? • How is breast self-awareness different from the traditional breast self-exam? •Glossary ... problems includes mammography , clinical breast exams, and breast self-awareness. What is mammography? Mammography is an X-ray ...

  3. Universal Design Problem Solving

    Science.gov (United States)

    Sterling, Mary C.

    2004-01-01

    Universal design is made up of four elements: accessibility, adaptability, aesthetics, and affordability. This article addresses the concept of universal design problem solving through experiential learning for an interior design studio course in postsecondary education. Students' experiences with clients over age 55 promoted an understanding of…

  4. Dynamical impurity problems

    International Nuclear Information System (INIS)

    In the past few years there has been a resurgence of interest in dynamical impurity problems, as a result of developments in the theory of correlated electron systems. The general dynamical impurity problem is a set of conduction electrons interacting with an impurity which has internal degrees of freedom. The simplest and earliest example, the Kondo problem, has attracted interest since the mid-sixties not only because of its physical importance but also as an example of a model displaying logarithmic divergences order by order in perturbation theory. It provided one of the earliest applications of the renormalization group method, which is designed to deal with just such a situation. As we shall see, the antiferromagnetic Kondo model is controlled by a strong-coupling fixed point, and the essence of the renormalization group solution is to carry out the global renormalization numerically starting from the original (weak-coupling) Hamiltonian. In these lectures, we shall describe an alternative route in which we identify an exactly solvable model which renormalizes to the same fixed point as the original dynamical impurity problem. This approach is akin to determining the critical behavior at a second order phase transition point by solving any model in a given universality class

  5. Microbiological problems in radiosterilization

    International Nuclear Information System (INIS)

    Microbiological problems connected with radiosterilization of medical materials, pharmaceuticals and cosmetics have been discussed in detail. Dose-response relationship for different bacteria has been shown. Recommended sterilization and postirradiation control procedures have been described. 24 refs, 6 figs, 5 tabs

  6. Unfolding a Problem

    Science.gov (United States)

    Currier, Sarah Cox

    2015-01-01

    In this article, Sarah Currier, a math specialist at Elizabeth Hall International School in Minnesota, describes how she used origami in a deliberate manner to teach content. She shares how she uses paper folding to teach mathematical concepts, reinforce vocabulary, and as a problem-solving model. She also offers ideas for using origami in other…

  7. Catastrophes control problem

    International Nuclear Information System (INIS)

    The problem of catastrophe control is discussed. Catastrophe control aims to withdraw responsible engineering constructions out of the catastrophe. The mathematical framework of catastrophes control systems is constructed. It determines the principles of systems filling by the concrete physical contents and, simultaneously, permits to employ modern control methods for the synthesis of optimal withdrawal strategy for protected objects

  8. The Classical Cake Problem

    Science.gov (United States)

    Nelson, Norman N.; Fisch, Forest N.

    1973-01-01

    Discussed are techniques of presentation and solution of the Classical Cake Problem. A frosted cake with a square base is to be cut into n pieces with the volume of cake and frosting the same for each piece. Needed are minimal geometric concepts and the formula for the volume of a prism. (JP)

  9. Nervous System Problems and Dementia

    Science.gov (United States)

    ... Language: Fact Sheet 505 Nervous System Problems and Dementia WHAT ARE NERVOUS SYSTEM PROBLEMS? WHAT ARE THE ... of AIDS these were all called “HIV-Associated Dementia.” However, a broader range of problems is showing ...

  10. How to solve mathematical problems

    CERN Document Server

    Wickelgren, Wayne A

    2012-01-01

    Seven problem-solving techniques include inference, classification of action sequences, subgoals, contradiction, working backward, relations between problems, and mathematical representation. Also, problems from mathematics, science, and engineering with complete solutions.

  11. No Problem? No Research, Little Learning ... Big Problem!

    Directory of Open Access Journals (Sweden)

    Fernando Ornelas Marques

    2012-06-01

    Full Text Available The motivation to carry out this study stemmed from the generalized perception that nowadays youth lacks the skills for the 21st century. Especially the high-level competences like critical thinking, problem solving and autonomy. Several tools can help to improve these competences (e.g. the SCRATCH programming language, but, as researchers and educators, we are mostly concerned with the skill to recognize problems. What if we do not find problems to solve? What if we do not even feel the need to find or solve problems? The problem is to recognize the problem; the next step is to equate the problem; finally we have to feel the need to solve it. No need? No invention. Recognizing a problem is probably the biggest problem of everyday life, because we are permanently faced with problems (many ill-defined problems, which we need to identify, equate and solve.

  12. The Potluck Problem

    CERN Document Server

    Enumula, Prabodh K

    2008-01-01

    This paper proposes the Potluck Problem as a model for the behavior of independent producers and consumers under standard economic assumptions. We model this by using resource allocation in a multi-agent system in which there is no explicit communication among the agents. The model proposed has many applications in modeling systems like electrical power grids with many consumers and producers, service-on-demand in grid computing and peer-to-peer computing environments, maintaining a good ratio between demand and inventory in supply chain management, etc. It is observed that a rational learning approach is unable to achieve equilibrium or near-equilibrium in the Potluck Problem. Instead, a weighted majority learning algorithm is applied, which does much better in maintaining parity of supply and demand in varying-demand situations.

  13. MCNP: Photon benchmark problems

    International Nuclear Information System (INIS)

    The recent widespread, markedly increased use of radiation transport codes has produced greater user and institutional demand for assurance that such codes give correct results. Responding to these pressing requirements for code validation, the general purpose Monte Carlo transport code MCNP has been tested on six different photon problem families. MCNP was used to simulate these six sets numerically. Results for each were compared to the set's analytical or experimental data. MCNP successfully predicted the analytical or experimental results of all six families within the statistical uncertainty inherent in the Monte Carlo method. From this we conclude that MCNP can accurately model a broad spectrum of photon transport problems. 8 refs., 30 figs., 5 tabs

  14. Problem discourse of textbook

    Directory of Open Access Journals (Sweden)

    Pešić Jelena M.

    2005-01-01

    Full Text Available This paper deals with various reasons for treating the problematisation of textbook discourse as an important aspect of its educational design. These reasons are derived from: the nature of learning process, the nature of scientific knowledge and both motivational and cognitive saint achieved through a problematisation of learning material. Implications drawn from these considerations, along with textbook genre possibilities and constrains, lead us to define some basic strategies of textbook discourse problematisation. They refer to: way of presenting knowledge (problem structuring of text, presenting the history of knowledge and different perspectives; use of specific questions and tasks; metacognitive support of the learning process and specific type of textbook language (dialogical problem focused, language of thinking.

  15. Problems of Chernobyl

    International Nuclear Information System (INIS)

    The digest comprises the scientific articles whose topics are streamlined to solving the problems of safe operation provision of the Ukryttia Object and its conversion into an ecologically safe systems, as well as the reporting materials on ISTC Shelters works in keeping with the Section 2.5 'ISCT Shelter's Works of nationwide significance' of 'Complex program of works at Ukryttia Object for the year of 2002'

  16. Creativity and Problem Solving

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2004-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving...... approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools....

  17. Creativity and problem Solving

    Directory of Open Access Journals (Sweden)

    René Victor Valqui Vidal

    2004-12-01

    Full Text Available This paper presents some modern and interdisciplinary concepts about creativity and creative processes of special relevance for Operational Research workers. Central publications in the area Creativity-Operational Research are shortly reviewed. Some creative tools and the Creative Problem Solving approach are also discussed. Finally, some applications of these concepts and tools are outlined. Some central references are presented for further study of themes related to creativity or creative tools.

  18. CULTURAL DOMAINS: TRANSLATION PROBLEMS

    OpenAIRE

    Isabel Negro Alousque

    2009-01-01

    Much of the lexis of a language has a cultural referent and is thus specific to a speech community. The meaning of culturally marked words is often difficult to grasp without some cultural knowledge and poses translation problems, particularly when the words are associated with cultural domains (Nida, 2001). In the present paper we focus on the French cultural domain of cooking. After outlining the elements of the domain, we analyse the difficulties in translating the lexical units from the d...

  19. Seismic Solvability Problems

    OpenAIRE

    Lau, August; Yin, Chuan

    2012-01-01

    Classical approach of solvability problem has shed much light on what we can solve and what we cannot solve mathematically. Starting with quadratic equation, we know that we can solve it by the quadratic formula which uses square root. Polynomial is a generalization of quadratic equation. If we define solvability by using only square roots, cube roots etc, then polynomials are not solvable by radicals (square root, cube root etc). We can classify polynomials into simple (solvable by radicals)...

  20. Kulturwissenschaftliche Probleme internationaler Managementforschung

    OpenAIRE

    Janzer, Alexander

    2007-01-01

    Diplom-Kulturwirt Alexander Janzer untersucht kulturwissenschaftliche Probleme der internationalen Managementforschung, die ihrerseits methodisch besonders häufig auf kulturvergleichende Umfrageforschung zurückgreift. This paper presents the most common errors of cross-cultural management research. Research in this field is based primarily on the concepts and methods of cross-cultural psychology (e.g. Hofstede 1980, Schwartz 1994, Triandis 1980). It is shown how current research from the C...

  1. Problems of adolescents sexuality.

    OpenAIRE

    Whatley, J.; Thin, N; B. Reynolds; Blackwell, A

    1989-01-01

    Recent discussions highlighted adolescents' sexual behaviour, but published studies concentrate on specific problems or subgroups of patients without addressing factors related to sexuality. To obtain a broad picture we studied two groups of adolescents attending genito-urinary medicine/sexually transmitted disease (STD) clinics in contrasting areas of Britain, inner London and Swansea. These were evaluated for referral pattern, sexual partner, contraception, obstetric history, sexually trans...

  2. Consumers and Agency Problems

    OpenAIRE

    Canice J. Prendergast

    2001-01-01

    Consumers solve many agency problems, by pointing out when they believe that agents have made mistakes. This paper considers the role that consumers play in inducing efficient behavior by agents. I distinguish between two case: those where consumers have similar preferences to the principal, and those where consumer preferences diverge from those of the principal. In the former case, allowing consumer feedback improves allocations, and increasing consumer information is unambiguously benefici...

  3. Problems of Chernobyl

    International Nuclear Information System (INIS)

    The collection comprises the materials of working meeting 'The Development of Technologies of the 'Ukrytie' Radioactive Waste Management', held on May 20-21, 1997 in Chernobyl. The results of research work of the experts of Ukraine and other countries directed on solving problems, concerning removal of fuel containing materials and other radioactive waste from destroyed Unit 4 of Chernobyl NPP are given. The data on waste quantities, their location and classification, strategy of waste management and some technologies are described

  4. Problem of hidden variables

    Science.gov (United States)

    Santos, Emilio

    1992-10-01

    The problem of hidden variables in quantum mechanics is formalized as follows. A general or contextual (noncontextual) hidden-variables theory is defined as a mapping f: Q×M → C (f: Q→C) where Q is the set of projection operators in the appropriate (quantum) Hilbert space, M is the set of maximal Boolean subalgebras of Q and C is a (classical) Boolean algebra. It is shown that contextual (noncontextual) hidden-variables always exist (do not exist).

  5. Smoking problem in Indonesia

    OpenAIRE

    Tjandra Y Aditama

    2002-01-01

    Smoking is an important public health probLem in Indonesia. Up to 60% of male adult population as well as about 4% of female adult population are smokers. In fact, some of Indonesian kretek cigarettes have quite high tar and nicotine content. Besides health effect, smoking habit also influence economic status of the individuals as well as the family. In health point of view, even though reliable nation wide morbidity and mortality data are scarce, report from various cities showed smoking rel...

  6. Europeanisation: Solution or problem?

    Directory of Open Access Journals (Sweden)

    Claudio M. Radaelli

    2004-10-01

    Full Text Available Is there something new in recent research on Europeanisation? Or should we go back to what we already know about political integration in Europe and avoid the term? This article reviews recent work in four steps: the identification of the specific domain of Europeanisation; the relationship between Europeanisation, on the one hand, and governance, institutions, and discourse, on the other; the methodological problems and the models emerging in this new field of research; and an assessment of the results arising out of theoretical and empirical research. One theme throughout the article is that, in order to develop a progressive agenda, Europeanisation should be seen as a problem, not as a solution. It is neither a new theory, nor an ad-hoc approach. Rather, it is a way of orchestrating existing concepts and to contribute to cumulative research in political science. Europeanisation does not provide any simple fix to theoretical or empirical problems. Quite the opposite, it can deliver if approached as a set of puzzles. A problem in search of explanation not the explanation itself (Gualini 2003. The conclusion is that Europeanisation has contributed to the emergence of new insights, original explanations, and interesting questions on three important issues: the understanding and analysis of 'impact', how to endogeneise international governance in models of domestic politics, and the relationship between agency and change. These three issues are prominent in the research agendas of international relations, theoretical policy analysis, and comparative politics. To contribute to major issues at the core of political science is a valuable result for a relatively new field of inquiry.

  7. Random eigenvalue problems revisited

    Indian Academy of Sciences (India)

    S Adhikari

    2006-08-01

    The description of real-life engineering structural systems is associated with some amount of uncertainty in specifying material properties, geometric parameters, boundary conditions and applied loads. In the context of structural dynamics it is necessary to consider random eigenvalue problems in order to account for these uncertainties. Within the engineering literature, current methods to deal with such problems are dominated by approximate perturbation methods. Some exact methods to obtain joint distribution of the natural frequencies are reviewed and their applicability in the context of real-life engineering problems is discussed. A new approach based on an asymptotic approximation of multi-dimensional integrals is proposed. A closed-form expression for general order joint moments of arbitrary numbers of natural frequencies of linear stochastic systems is derived. The proposed method does not employ the ‘small randomness’ assumption usually used in perturbation based methods. Joint distributions of the natural frequencies are investigated using numerical examples and the results are compared with Monte Carlo simulation.

  8. Quantum Counterfeit Coin Problems

    CERN Document Server

    Iwama, Kazuo; Raymond, Rudy; Teruyama, Junichi

    2010-01-01

    The counterfeit coin problem requires us to find all false coins from a given bunch of coins using a balance scale. We assume that the balance scale gives us only ``balanced'' or ``tilted'' information and that we know the number k of false coins in advance. The balance scale can be modeled by a certain type of oracle and its query complexity is a measure for the cost of weighing algorithms (the number of weighings). In this paper, we study the quantum query complexity for this problem. Let Q(k,N) be the quantum query complexity of finding all k false coins from the N given coins. We show that for any k and N such that k < N/2, Q(k,N)=O(k^{1/4}), contrasting with the classical query complexity, \\Omega(k\\log(N/k)), that depends on N. So our quantum algorithm achieves a quartic speed-up for this problem. We do not have a matching lower bound, but we show some evidence that the upper bound is tight: any algorithm, including our algorithm, that satisfies certain properties needs \\Omega(k^{1/4}) queries.

  9. Medical problems of musicians.

    Science.gov (United States)

    Lockwood, A H

    1989-01-26

    Surveys of performing musicians indicate that almost half of them experience playing-related medical problems, some of which threaten or end their careers. Overuse injuries involving the muscle--tendon unit are the most common problem, with symptoms ranging from mild pain while the musician is playing to pain severe enough to preclude any use of the affected hand. String players are the most commonly affected, and percussionists the least. The most important predisposing characteristic is the use of repetitive movements during long hours of practice, but awkward body positions mandated by the shape and weight of the instrument, the technical difficulty of the repertoire, and unfamiliar instruments may also play a part. Women are more commonly affected than men. Rest is the cornerstone of therapy. Neural impingement syndromes affecting the median or ulnar nerves or the thoracic outlet affect many musicians. Focal dystonias may involve part or all of a hand or the muscles forming the embouchure (the position of the lips in wind players). These are very resistant to therapy and may terminate or drastically alter a career. Stress, especially performance anxiety, may impede performance. Beta-adrenergic blocking agents prevent the symptoms of performance anxiety and are frequently used by musicians without medical supervision. A recognition of the unique problems of musician-patients has led to the formation of successful specialty clinics in a number of cities. PMID:2643048

  10. Characteristics of Problems in Problem-based Learning

    NARCIS (Netherlands)

    N. Sockalingam (Nachamma)

    2010-01-01

    textabstractThis thesis focuses on characteristics of problems in Problem-based Learning (PBL). Problems initiate the students’ learning process in PBL. Several studies have shown that the quality of problems has a positive influence on students’ academic achievement and interest. In addition, the q

  11. Obstacle problems in mathematical physics

    CERN Document Server

    Rodrigues, J-F

    1987-01-01

    The aim of this research monograph is to present a general account of the applicability of elliptic variational inequalities to the important class of free boundary problems of obstacle type from a unifying point of view of classical Mathematical Physics.The first part of the volume introduces some obstacle type problems which can be reduced to variational inequalities. Part II presents some of the main aspects of the theory of elliptic variational inequalities, from the abstract hilbertian framework to the smoothness of the variational solution, discussing in general the properties of the free boundary and including some results on the obstacle Plateau problem. The last part examines the application to free boundary problems, namely the lubrication-cavitation problem, the elastoplastic problem, the Signorini (or the boundary obstacle) problem, the dam problem, the continuous casting problem, the electrochemical machining problem and the problem of the flow with wake in a channel past a profile.

  12. Direct Problems and Inverse Problems in Biometric Systems

    OpenAIRE

    Mihailescu Marius Iulian

    2013-01-01

    The article purpose is to describe the two sides of biometrics technologies, direct problems and inverse problems. The advance that we face today in field of Information Technology makes Information Security an inseparable part. The authentication has a huge role when we deal about security. The problems that can appear in implementing and developing biometrics systems is raising many problems, and one of the goal of this article is to focus on direct and inverse problems which is a new and c...

  13. Characteristics of Problems in Problem-based Learning

    OpenAIRE

    Sockalingam, Nachamma

    2010-01-01

    textabstractThis thesis focuses on characteristics of problems in Problem-based Learning (PBL). Problems initiate the students’ learning process in PBL. Several studies have shown that the quality of problems has a positive influence on students’ academic achievement and interest. In addition, the quality of problems has been shown to have a higher influence than the tutor’s performance and students’ prior knowledge on students’ learning. The implication of these findings is that designing go...

  14. The world food problem

    International Nuclear Information System (INIS)

    Argument continues in the world press as to the urgency of the food problem. Some economists in equating world food production statistics with population figures have convinced themselves there is more than enough food per capita and, accordingly, no problem. Looking in greater depth than these gross averages, however, we find that there is indeed a prospective problem, and of such a nature and magnitude as to tax all of mankind's talents and resources in its resolution. It is true that certain of the developed countries of the world in the last generation acquired agricultural production capabilities that notably exceeded the resident population's capacity to consume. 'Surplus' in these areas became an ugly word during this period of a generally favorable weather cycle, and restrictions on the amount of and that could be devoted to graincrops were imposed to curb this tremendous capacity. A fickle Mother Nature, however, has turned things around during the early 1970's by one or another of her many vacillations in the form of local drought, excess moisture, shortened growing season, or other means, in some of the major producing areas. Inconsequence, the food grain surpluses are now gone and the world is looking at a three to four week reserve at any given moment. The cost of food products available from exporting countries has doubled and trebled in price during the past two years. The potential for famine exceeds in magnitude anything the world has ever known. It is against this background that the World Food Conference will be held in Rome during November of this year. (author)

  15. PROBLEM KORUPCIJE V ZDRAVSTVU

    OpenAIRE

    Drevenšek, Sanja

    2016-01-01

    Korupcija je kompleksen pojav in vse večji problem v vseh državah tudi v Sloveniji. Pojavlja se v različnih oblikah, njene posledice pa so uničujoče za širšo družbo, državo kakor tudi za vsakega posameznika. Problematika je sicer v Sloveniji urejena z zakonodajo, ki je primerljiva z evropsko zakonodajo o preprečevanju korupcije. Ustanovljeno imamo tudi Komisijo za preprečevanje korupcije kot samostojen in neodvisen državni organ, katerega temeljno poslanstvo je doseči ničelno toleranco do kor...

  16. Conway's napkin problem

    OpenAIRE

    Claesson, Anders; Petersen, T. Kyle

    2005-01-01

    The napkin problem was first posed by John H. Conway, and written up as a `toughie' in "Mathematical Puzzles: A Connoisseur's Collection," by Peter Winkler. To paraphrase Winkler's book, there is a banquet dinner to be served at a mathematics conference. At a particular table, $n$ men are to be seated around a circular table. There are $n$ napkins, exactly one between each of the place settings. Being doubly cursed as both men and mathematicians, they are all assumed to be ignorant of table e...

  17. The Container Stowage Problem

    DEFF Research Database (Denmark)

    Janstrup, Kira; Rose, Trine Høyer; Andersen, Kent Høj;

    The main purpose of this project is to use integer programming to create a model that minimizes the costs for container transportation by ship. To make the model as realistic as possible it will be based on information from a large shipping company about the vessel layout and container types. In...... addition to our project two other projects are made where an optimal solution to the container stowage problem also is tried to be found, but by using constraint programming and local search instead respectively. We will therefore in the end compare these three methods and the achieved results on fastness...

  18. XML problem, design, solution

    CERN Document Server

    Amiano, Mitch; Ethier, Kay; Thomas, Michael D

    2006-01-01

    Offering a unique approach to learning XML, this book walks readers through the process of building a complete, functional, end-to-end XML solutionFeatured case study is an online business product catalog that includes reports, data input/output, workflow, stylesheet formatting, RSS feeds, and integration with external services like Google, eBay, and AmazonThe format of presenting a problem and working through the design to come up with a solution enables readers to understand how XML markup allows a business to share data across applications internally or with partners or customers even thoug

  19. Dirac's Quantum Phase Problem

    OpenAIRE

    Sperling, J.; Vogel, W

    2009-01-01

    In 1927 the great physicist Paul A. M. Dirac failed to provide a consistent quantum description of the phase of a radiation field. Only one year later, he developed the famous Dirac theory of the electron, which led to the anti-particle -- the positron. We show that the reason for Dirac's failure with the phase problem bears a striking resemblance to his ingenious insight into the nature of the electron. For a correct quantum description of the phase of a radiation field it is necessary to ta...

  20. Mechanics: Ideas, problems, applications

    Science.gov (United States)

    Ishlinskii, A. Iu.

    The book contains the published articles and reports by academician Ishlinskii which deal with the concepts and ideas of modern mechanics, its role in providing a general understanding of the natural phenomena, and its applications to various problems in science and engineering. Attention is given to the methodological aspects of mechanics, to the history of the theories of plasticity, friction, gyroscopic and inertial systems, and inertial navigation, and to mathematical methods in mechanics. The book also contains essays on some famous scientists and engineers.

  1. The Gilbert Arborescence Problem

    CERN Document Server

    Volz, M G; Ras, C J; Swanepoel, K J; Thomas, D A

    2009-01-01

    We investigate the problem of designing a minimum cost flow network interconnecting n sources and a single sink, each with known locations and flows. The network may contain other unprescribed nodes, known as Steiner points. For concave increasing cost functions, a minimum cost network of this sort has a tree topology, and hence can be called a Minimum Gilbert Arborescence (MGA). We characterise the local topological structure of Steiner points in MGAs, showing, in particular, that for a wide range of metrics and cost-functions the degree of each Steiner point is 3.

  2. Pizza Race Problem

    OpenAIRE

    Gao, Keyue

    2012-01-01

    This paper deals with a problem in which two players share a previously sliced pizza and try to eat as much amount of pizza as they can. It takes time to eat each piece of pizza and both players eat pizza at the same rate. One is allowed to take a next piece only after the person has finished eating the piece on hand. Also, after the first piece is taken, one can only take a piece which is adjacent to already-taken piece. This paper shows that, in this real time setting, the starting player c...

  3. Problems of Massive Gravities

    CERN Document Server

    Deser, S; Ong, Y C; Waldron, A

    2014-01-01

    The method of characteristics is a key tool for studying consistency of equations of motion; it allows issues such as predictability, maximal propagation speed, superluminality, unitarity and acausality to be addressed without requiring explicit solutions. We review this method and its application to massive gravity theories to show the limitations of these models' physical viability: Among their problems are loss of unique evolution, superluminal signals, matter coupling inconsistencies and micro-acausality (propagation of signals around local closed timelike/causal curves). We extend previous no-go results to the entire three-parameter range of massive gravity theories. It is also argued that bimetric models suffer a similar fate.

  4. The leap year problem

    OpenAIRE

    Deursen, van, A

    1998-01-01

    A significant number of programs incorrectly treats the year 2000 as a non-leap year. We list 21 real life code fragments illustrating the large variety of ways that are used to determine whether a given year is a leap year or not. Some of these fragments are correct; others will fail in the year 2000. The fragments are written in C, Pascal, COBOL, and assembly language. We discuss the consequences for automated tool support, as well as the organizational implications of the leap year problem.

  5. Embedded Plateau Problem

    OpenAIRE

    Coşkunuzer, Barış

    2010-01-01

    TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY Volume 364, Number 3, March 2012, Pages 1211–1224 S 0002-9947(2011)05486-3 Article electronically published on October 19, 2011 EMBEDDED PLATEAU PROBLEM BARIS COSKUNUZER Abstract. We show that if Γ is a simple closed curve bounding an embedded disk in a closed 3-manifold M, then there exists a disk Σ in M with boundary Γ such that Σ minimizes the area among the embedded disks with boundary Γ. Moreover, Σ is smooth...

  6. Problem Order Implications for Learning

    Science.gov (United States)

    Li, Nan; Cohen, William W.; Koedinger, Kenneth R.

    2013-01-01

    The order of problems presented to students is an important variable that affects learning effectiveness. Previous studies have shown that solving problems in a blocked order, in which all problems of one type are completed before the student is switched to the next problem type, results in less effective performance than does solving the problems…

  7. Analysis of the tracing problem

    Institute of Scientific and Technical Information of China (English)

    Nanfeng Jie; Hui Wang; YunqingSun

    2005-01-01

    Here the tracing problems are researched from two thoroughly different approaches: calculus method and numerical analysis. Generally speaking, the calculus method give a universal qualitative way to deal with such kind of problem, but the numerical analysis method can offer more further quantitative result for such kind of problem. Our research shows the detail results of application of these two methods in tracing problem.

  8. Double pendulum contact problem

    Directory of Open Access Journals (Sweden)

    Špička J.

    2014-06-01

    Full Text Available The work concerns contact problems focused on biomechanical systems modelled by a multibody approach. The example is modelling of impact between a body and an infrastructure. The paper firstly presents algorithm for minimum distance calculation. An analytical approach using a tangential plain perpendicular to an initial one is applied. Contact force generated during impact is compared by three different continuous force models, namely the Hertz’s model, the spring-dashpot model and the non-linear damping model. In order to identify contact parameters of these particular models, the method of numerical optimization is used. Purpose of this method is to find the most corresponding results of numerical simulation to the original experiment. Numerical optimization principle is put upon a bouncing ball example for the purpose of evaluation of desirable contact force parameters. The contact modelling is applied to a double pendulum problem. The equation of motion of the double pendulum system is derived using Lagrange equation of the second kind with multipliers, respecting the contact phenomena. Applications in biomechanical research are hinted at arm gravity motion and a double pendulum impact example.

  9. Decomposition Approaches for Optimization Problems

    OpenAIRE

    Kinable, Joris

    2014-01-01

    This dissertation encompasses the development of decomposition approaches for a variety of both real-world and fundamental optimization problems. Many optimization problems comprise of multiple interconnected subproblems, often rendering them too large or too complicated to solve as a single integral problem. Decomposition approaches are required to deal with these problems efficiently. By decomposing a problem into multiple subproblems, efficient dedicated procedures can be employed to solve...

  10. Combinatorial problems in mathematical competitions

    CERN Document Server

    Yao, Zhang

    2011-01-01

    This book focuses on combinatorial problems in mathematical competitions. It provides basic knowledge on how to solve combinatorial problems in mathematical competitions, and also introduces important solutions to combinatorial problems and some typical problems with often-used solutions. Some enlightening and novel examples and exercises are well chosen in this book. With this book, readers can explore, analyze and summarize the ideas and methods of solving combinatorial problems. Their mathematical culture and ability will be improved remarkably after reading this book.

  11. Some Undecidable Problems on Approximability of NP Optimization Problems

    Institute of Scientific and Technical Information of China (English)

    黄雄

    1996-01-01

    In this paper some undecidable problems on approximability of NP optimization problems are investigated.In particular,the following problems are all undecidable:(1) Given an NP optimization problem,is it approximable in polynomial time?(2)For any polynomial-time computable function r(n),given a polynomial time approximable NP optimization problem,has it a polynomial-time approximation algorithm with approximation performance ratio r(n) (r(n)-approximable)?(3)For any polynomial-time computable functions r(n),r'(n),where r'(n)problem,is it r'(n)-approximable?

  12. Understanding the Problem. Problem Solving and Communication Activity Series. The Math Forum: Problems of the Week

    Science.gov (United States)

    Math Forum @ Drexel, 2009

    2009-01-01

    Different techniques for understanding a problem can lead to ideas for never-used-before solutions. Good problem-solvers use a problem-solving strategy and may come back to it frequently while they are working on the problem to refine their strategy, see if they can find better solutions, or find other questions. Writing is an integral part of…

  13. The landslide problem

    Institute of Scientific and Technical Information of China (English)

    G. Shanmugam

    2015-01-01

    The synonymous use of the general term“landslide”, with a built-in reference to a sliding motion, for all varieties of mass-transport deposits (MTD), which include slides, slumps, debrites, topples, creeps, debris avalanches etc. in subaerial, sublacustrine, sub-marine, and extraterrestrial environments has created a multitude of conceptual and nomen-clatural problems. In addition, concepts of triggers and long-runout mechanisms of mass movements are loosely applied without rigor. These problems have enormous implications for studies in process sedimentology, sequence stratigraphy, palaeogeography, petroleum geol-ogy, and engineering geology. Therefore, the objective of this critical review is to identify key problems and to provide conceptual clarity and possible solutions. Speciifc issues are the fol-lowing:(1) According to“limit equilibrium analyses”in soil mechanics, sediment failure with a sliding motion is initiated over a shear surface when the factor of safety for slope stability (F) is less than 1. However, the term landslide is not meaningful for debris lfows with a lfowing mo-tion. (2) Sliding motion can be measured in oriented core and outcrop, but such measurement is not practical on seismic proifles or radar images. (3) Although 79 MTD types exist in the geological and engineering literature, only slides, slumps, and debrites are viable depositional facies for interpreting ancient stratigraphic records. (4) The use of the term landslide for high-velocity debris avalanches is inappropriate because velocities of mass-transport processes cannot be determined in the rock record. (5) Of the 21 potential triggering mechanisms of sediment failures, frequent short-term events that last for only a few minutes to several hours or days (e.g., earthquakes, meteorite impacts, tsunamis, tropical cyclones, etc.) are more relevant in controlling deposition of deep-water sands than sporadic long-term events that last for thousands to millions of years (e

  14. Problems of Chernobyl

    International Nuclear Information System (INIS)

    This collection comprises the materials of the VI International Conference 'Shelter' Object', 15 years: today and future'. The topics of this issue's works cover the results of 15-year operation of the Shelter Object and investigations of conditions of its nuclear-, radiation- and general technical safety, procedures of monitoring of fuel-containing material conditions, building structures, problems of object's conversion into an ecologically safe system, preparation of technologies for radwaste (RW) management, working out of procedures using the remotely controlled facilities for diagnostics, prospecting of complicated in access Shelter Object premises, RW retrieval and management, etc. A very important role play the works aimed at the upgrade of radiation safety, protection of public and environment

  15. Financing and insurance problems

    International Nuclear Information System (INIS)

    The author analyses the papers presented at the Paris Conference on the maturity of nuclear energy. It is evident that financing possibilities will be a determinant factor in the rate of development of nuclear power during the years to come. After having evaluated the capital requirements necessitated for the development of nuclear programmes, the parties intervening have examined the means at the disposal of electricity manufacturers to meet these needs (self-financing, recourse to external financing, regrouping, on an international scale of the electricity manufacturers of the setting up of high capacity plants). As concerns the insurance problems, they are becoming more and more involved as nuclear applications, are further diversified and intensified. The parties intervening have discussed new tarification techniques likely to be applied and pointed out the possibilities offered by regrouping or pooling of insurers (Market Pool) which allow for a maximum of risks to be covered without exceeding the means proper to each company concerned

  16. Problems in risk comparisons

    International Nuclear Information System (INIS)

    Risk comparisons are usually made for some specific purpose (to help communicating the message that a situation is either acceptable or not acceptable). However, the communication should be fair and, as the author of the next Chapter says: relevant, adequate, understandable and credible. Since ''risk'' has many attributes, the characterization of risks to be compared must involve appropriately compared attributes. The author of this Chapter begins by discussing the difficult task of risk characterization before he deals with the problems involved in risk comparison. He finally refers to the principle of ceteris paribus, which means that, in risk comparisons, all factors, circumstances and assumptions which are not explicitly presented in the risk characterization and quantification must be mutually equivalent. (author). 14 refs, 1 tab

  17. A stochastic control problem

    Directory of Open Access Journals (Sweden)

    William Margulies

    2004-11-01

    Full Text Available In this paper, we study a specific stochastic differential equation depending on a parameter and obtain a representation of its probability density function in terms of Jacobi Functions. The equation arose in a control problem with a quadratic performance criteria. The quadratic performance is used to eliminate the control in the standard Hamilton-Jacobi variational technique. The resulting stochastic differential equation has a noise amplitude which complicates the solution. We then solve Kolmogorov's partial differential equation for the probability density function by using Jacobi Functions. A particular value of the parameter makes the solution a Martingale and in this case we prove that the solution goes to zero almost surely as time tends to infinity.

  18. Some engineering problems

    Directory of Open Access Journals (Sweden)

    H. Williams

    1952-07-01

    Full Text Available It will help delegates to realize something of the range and magnitude of Service equipment problems if I touch on a few of the many important items which concern the Corps of Engineers in their preparations for war. The Engineers' role in battle is to assist our own forces to maintain their mobility by the passage of obstacles of every, description, the construction of roads and tracks and by meeting the Air Force's requirements airfields and air-strips. Secondly, to deny mobility to the enemy's forces by creating obstacles by demolitions and the destruction of materials, and by the construction of weapon positions and shelters. And lastly to support the administrative machine by supplying water, bulk fuel, power and Engineer stores where required, by meeting the Army's Transportation needs and in numerous other ways dependent on Engineering.

  19. The Password Problem

    Energy Technology Data Exchange (ETDEWEB)

    Walkup, Elizabeth [Stanford Univ., CA (United States)

    2016-06-01

    Passwords are an ubiquitous, established part of the Internet today, but they are also a huge security headache. Single sign-on, OAuth, and password managers are some of the solutions to this problem. OAuth is a new, popular method that allows people to use large, common authentication providers for many web applications. However, it comes at the expense of some privacy: OAuth makes users easy to track across websites, applications, and devices. Password managers put the power in the hands of the users, but this vulnerability survey reveals that you have to be extremely careful which program you choose. All in all, password managers are the solution of choice for home users and small organizations, but large companies will probably want to invest in their own SSO solutions.

  20. The global warming problem

    International Nuclear Information System (INIS)

    In this chapter, a discussion is presented of the global warming problem and activities contributing to the formation of acid rain, urban smog and to the depletion of the ozone layer. Globally, about two-thirds of anthropogenic carbon dioxide emissions arise from fossil-fuel burning; the rest arise primarily from deforestation. Chlorofluorocarbons are the second largest contributor to global warming, accounting for about 20% of the total. The third largest contributor is methane, followed by ozone and nitrous oxide. A study of current activities in the US that contribute to global warming shows the following: electric power plants account for about 33% of carbon dioxide emissions; motor vehicles, planes and ships (31%); industrial plants (24%); commercial and residential buildings (11%)

  1. Seismic Solvability Problems

    CERN Document Server

    Lau, August

    2012-01-01

    Classical approach of solvability problem has shed much light on what we can solve and what we cannot solve mathematically. Starting with quadratic equation, we know that we can solve it by the quadratic formula which uses square root. Polynomial is a generalization of quadratic equation. If we define solvability by using only square roots, cube roots etc, then polynomials are not solvable by radicals (square root, cube root etc). We can classify polynomials into simple (solvable by radicals) and complex (not solvable by radicals). We will use the same metaphor to separate what is solvable (simple part) and what is not solvable (complex part). This paper is a result of our presentation at a University of Houston seminar. In this paper, we will study seismic complexity through the eyes of solvability. We will investigate model complexity, data complexity and operator complexity. Model complexity is demonstrated by multiple scattering in a complex model like Cantor layers. Data complexity is studied through Bet...

  2. Problems of massive gravities

    Science.gov (United States)

    Deser, S.; Izumi, K.; Ong, Y. C.; Waldron, A.

    2015-01-01

    The method of characteristics is a key tool for studying consistency of equations of motion; it allows issues such as predictability, maximal propagation speed, superluminality, unitarity and acausality to be addressed without requiring explicit solutions. We review this method and its application to massive gravity (mGR) theories to show the limitations of these models' physical viability: Among their problems are loss of unique evolution, superluminal signals, matter coupling inconsistencies and micro-acausality (propagation of signals around local closed time-like curves (CTCs)/closed causal curves (CCCs)). We extend previous no-go results to the entire three-parameter range of mGR theories. It is also argued that bimetric models suffer a similar fate.

  3. Problems in particle theory

    International Nuclear Information System (INIS)

    Members of the Institute have worked on a number of problems including the following: acceleration algorithms for the Monte Carlo analysis of lattice field, and gauge and spin theories, based on changes of variables specific to lattices of dimension 2ell; construction of quaternionic generalizations of complex quantum mechanics and field theory; wave functions for paired Hall states; black hole quantum mechanics; generalized target-space duality in curved string backgrounds; gauge symnmetry algebra of the N = 2 string; two-dimensional quantum gravity and associated string theories; organizing principles from which the signal processing of neural networks in the retina and cortex can be deduced; integrable systems of KdV type; and a theory for Kondo insulators

  4. Problems of nuclear waste

    International Nuclear Information System (INIS)

    An enormous stockpile of nuclear weapons was reduced during the Cold War as a result of frantic Soviet-US competition, accompanied by considerable radioactive pollution of the environment. This pollution was inevitable. Former adversaries began to sober only recently. As a result, areas of weapons complexes both in the USA (Hanford, Savannah, Oak Ridge) and in Russia (Chelyabinsk-65, Tomsk-7, Krasnoyarsk-25) look like battlefields of the Cold War. A Nuclear weapon-free world will only be achieved (if at all) after reaching changes in the principles that guide state policies and actions. A nuclear-waste-free world implies that the environment's radioactive pollution of a military nature would be eliminated and all potential dangers from civil nuclear energy prevented. This can be attained after solution of some economic, political and social problems

  5. Wicked Problem Solvers.

    Science.gov (United States)

    Edmondson, Amy C

    2016-06-01

    Companies today increasingly rely on teams that span many industries for radical innovation, especially to solve "wicked problems." So leaders have to understand how to promote collaboration when roles are uncertain, goals are shifting, expertise and organizational cultures are varied, and participants have clashing or even antagonistic perspectives. HBS professor Amy Edmondson has studied more than a dozen cross-industry innovation projects, among them the creation of a new city, a mango supply-chain transformation, and the design and construction of leading-edge buildings. She has identified the leadership practices that make successful cross-industry teams work: fostering an adaptable vision, promoting psychological safety, enabling knowledge sharing, and encouraging collaborative innovation. Though these practices are broadly familiar, their application within cross-industry teams calls for unique leadership approaches that combine flexibility, open-mindedness, humility, and fierce resolve. PMID:27491195

  6. Fra problemer til mirakler

    DEFF Research Database (Denmark)

    Görlich, Anne; Katznelson, Noemi; Stentoft, Mette

    Uddannelsessystemet rummer i dag en stor del af de sårbare og udsatte unge, der tidligere havde ufaglærte jobs eller var på kontanthjælp. Det skaber udfordringer i forhold til den politiske målsætning om, at 95 procent af en ungdomsårgang skal gennemføre en ungdomsuddannelse. Disse udfordringer har...... været omdrejningspunktet i Skive Kommunes projekt ’Fra problemer til mirakler’, hvor man har søgt at styrke sårbare unges selvtillid, motivation for og deltagelse i en kompetencegivende uddannelse og dermed holde dem ude af kontanthjælpssystemet....

  7. The solar neutrino problem

    International Nuclear Information System (INIS)

    The problem of missing solar neutrinos is reviewed and discussed. The experiments of the 70s show a solar neutrino flux to be 4 times lower than the flux predicted by the standard model of the Sun. The three possible origins of this contradiction are analysed: the cross sections of nuclear reactions going on in the internal region of the Sun must be remeasured; the unknown properties of neutrino, like neutrino oscillation or decay, must be investigated theoretically and experimentally; or the standard model of the Sun must be changed, e.g. by a periodically pulsating star model or by a model describing periodic admixtures of He-3 to the central region of the Sun. Some new models and newly proposed experiments are described. The importance of new electronic detection methods of neutrinos is underlined. (D.Gy.)

  8. The worldwide "wildfire" problem.

    Science.gov (United States)

    Gill, A Malcolm; Stephens, Scott L; Cary, Geoffrey J

    2013-03-01

    The worldwide "wildfire" problem is headlined by the loss of human lives and homes, but it applies generally to any adverse effects of unplanned fires, as events or regimes, on a wide range of environmental, social, and economic assets. The problem is complex and contingent, requiring continual attention to the changing circumstances of stakeholders, landscapes, and ecosystems; it occurs at a variety of temporal and spatial scales. Minimizing adverse outcomes involves controlling fires and fire regimes, increasing the resistance of assets to fires, locating or relocating assets away from the path of fires, and, as a probability of adverse impacts often remains, assisting recovery in the short-term while promoting the adaptation of societies in the long-term. There are short- and long-term aspects to each aspect of minimization. Controlling fires and fire regimes may involve fire suppression and fuel treatments such as prescribed burning or non-fire treatments but also addresses issues associated with unwanted fire starts like arson. Increasing the resistance of assets can mean addressing the design and construction materials of a house or the use of personal protective equipment. Locating or relocating assets can mean leaving an area about to be impacted by fire or choosing a suitable place to live; it can also mean the planning of land use. Assisting recovery and promoting adaptation can involve insuring assets and sharing responsibility for preparedness for an event. There is no single, simple, solution. Perverse outcomes can occur. The number of minimizing techniques used, and the breadth and depth of their application, depends on the geographic mix of asset types. Premises for policy consideration are presented. PMID:23634593

  9. Radiological problems in Kazakhstan

    International Nuclear Information System (INIS)

    Kazakhstan historical development and available mineral resources have pre-determined a scale of radiological problems in the state. Kazakhstan keeps leading positions in the world in explored uranium resources and hydrocarbon raw. More than five hundred nuclear explosions were performed in various regions of Kazakhstan. There is necessity to carry out remediation actions at the former test sites of Kazakhstan, especially at the Semipalatinsk test-site (STS). But because of the high cost of such actions it should be expedient to carry out them only in case of emergency and inclusion of the former test sites lands to the national economic activity, as in general, under conditions of competent policy of inhabitants, STS doesn't represent a hazard. At the same time, we ought not to lose an invaluable scientific material of test-sites. It is necessary to keep some areas of Semipalatinsk test-site as a rarities, reflected the important stages of the human evolution. Test-sites should be considered as world laboratory for studies of artificial radionuclides behaviour in natural medium. Illustrations of radiation-hazardous objects, of used technologies and procedures, under the Kazakhstan Republic instance, show that main power industries lead to the common increase of radioactivity materials in human environment. Mankind certainly will become aware of fact that industrial activities, under the current level of science and technologies development, will lead to the common increase of radioactivity materials in human environment. Solving of radioecological problems is possible only when people review their approach to a radioactivity, as a whole. Not only specialists involved in this field, but also all local population have to know rules of radiation safety and how reasonable manage with radioactive materials

  10. International safeguards problem

    International Nuclear Information System (INIS)

    To recognize the limitations of safeguards as a barrier to nuclear proliferation is not to deny their essential role in the effort to contain that problem. Without a safeguards system, international nuclear commerce and development would not, indeed could not, be what they are today. The problems evoked in the discussion of the spread of sensitive nuclear technology underscore the importance of ensuring that activities do not outpace our ability to control them. To sustain a global nuclear economy requires a readiness to live within the constraints that such an economy requires. Enhanced safeguards and strengthened national commitments to facilitate their application are key elements of those constraints. So also may be a prepardness by many nations to forego explicitly national control over all facets of the nuclear fuel cycle while still sharing fully and equally in the benefits of the peaceful atom. The challenge of the coming years will be to craft mechanisms and institutions enabling the continued growth of peaceful nuclear activity without further impairing international security. The constraints that such an outcome entails are not limited to nations lacking sophisticated nuclear technology; they apply to the most advanced nuclear nations as well--partly through adherence to the safeguards system that these countries call upon others to adopt, and partly through greater willingness to entertain solutions that may involve greater international involvement in, and control over, their own peaceful nuclear productive activities. With time, the relative incompatibility of nuclear energy with full national sovereignty, and the far-sighted wisdom of the Baruch Plan, are becoming increasingly clear. 1 table, 10 references

  11. On Brauer's problem 21

    Institute of Scientific and Technical Information of China (English)

    ZENG; Jiwen(

    2001-01-01

    [1]Brauer, R., Representations of finite groups, in Lectures in Mathematics, Vol. 1, New York: Wiley, 1963, 133-175.[2]Feit, W. , The Representation Theory of Finite Groups, Amsterdam: North-Holland, 1982.[3]Külshammer, B., Landau's theorem for p-blocks of p-solvable groups, J. Reine Angew. Math., 1990, 404: 189-191.[4]Külshammer B., Robinson, G. R., Alperin-Mckey implies Brauer's problem 21, J. Algebra, 1996, 180: 208-210.[5]Zeng Jiwen, An inequality of block invariants, J. Algebra, 1997, 193: 724-727.[6]Nagao, N., Tsushima, Y., Representations of Finite Groups, New York: Academic Press, Inc., 1989.[7]Robinson, G. R., On Brauer's k(B) problem, J. Algebra, 1992, 147: 450-455.[8]Zhang Jiping, p-regular orbits and p-blocks of defect zero, Comm. Algebra, 1993, 21(1): 299-307.[9]Xu Minyao, Huang ,Jianhua, An Introduction to Finite Groups (in Chinese), Vol. 2, Beijing: Science Press, 1999.[10]Alperin, ,J. L. , Weights for finite group, Proc. Sympos. Pure Math. , 1987, 47: 369-379.[11]Puig, L., Usami, Y., Perfect isometrics for blocks with Abelian defect groups and cyclic four inertial quotients, J. Algebra,1996.[12]Dade, E. C., Counting characters in blocks, I, Invent. Math., 1992, 109: 187-210.

  12. Fostering Information Problem Solving Skills Through Completion Problems and Prompts

    OpenAIRE

    Frerejean, Jimmy; Brand-Gruwel, Saskia; Kirschner, Paul A.

    2012-01-01

    Frerejean, J., Brand-Gruwel, S., & Kirschner, P. A. (2012, September). Fostering Information Problem Solving Skills Through Completion Problems and Prompts. Poster presented at the EARLI SIG 6 & 7 "Instructional Design" and "Learning and Instruction with Computers", Bari, Italy.

  13. Fostering information problem solving skills through completion problems and prompts

    OpenAIRE

    Frerejean, Jimmy; Brand-Gruwel, Saskia; Kirschner, Paul A.

    2012-01-01

    Frerejean, J., Brand-Gruwel, S., & Kirschner, P. A. (2012, November). Fostering information problem solving skills through completion problems and prompts. Poster presented at the ICO Fall School 2012, Girona, Spain.

  14. Kolkata Restaurant Problem as a Generalised El Farol Bar Problem

    Science.gov (United States)

    Chakrabarti, Bikas K.

    Generalisation of the El Farol bar problem to that of many bars here leads to the Kolkata restaurant problem, where the decision to go to any restaurant or not is much simpler (depending on the previous experience of course, as in the El Farol bar problem). This generalised problem can be exactly analysed in some limiting cases discussed here. The fluctuation in the restaurant service can be shown to have precisely an inverse cubic behavior, as widely seen in the stock market fluctuations.

  15. Mechanics problems in undergraduate physics

    CERN Document Server

    Strelkov, S P

    2013-01-01

    Problems in Undergraduate Physics, Volume I: Mechanics focuses on solutions to problems in physics. The book first discusses the fundamental problems in physics. Topics include laws of conservation of momentum and energy; dynamics of a point particle in circular motion; dynamics of a rotating rigid body; hydrostatics and aerostatics; and acoustics. The text also offers information on solutions to problems in physics. Answers to problems in kinematics, statics, gravity, elastic deformations, vibrations, and hydrostatics and aerostatics are discussed. Solutions to problems related to the laws of

  16. Sherlock Holmes, Master Problem Solver.

    Science.gov (United States)

    Ballew, Hunter

    1994-01-01

    Shows the connections between Sherlock Holmes's investigative methods and mathematical problem solving, including observations, characteristics of the problem solver, importance of data, questioning the obvious, learning from experience, learning from errors, and indirect proof. (MKR)

  17. Dementia - behavior and sleep problems

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000029.htm Dementia - behavior and sleep problems To use the sharing ... on this page, please enable JavaScript. People with dementia often have certain problems when it gets dark ...

  18. ON VECTOR NETWORK EQUILIBRIUM PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Guangya CHEN

    2005-01-01

    In this paper we define a concept of weak equilibrium for vector network equilibrium problems.We obtain sufficient conditions of weak equilibrium points and establish relation with vector network equilibrium problems and vector variational inequalities.

  19. Eldercare at Home: Communication Problems

    Science.gov (United States)

    ... improving it. It is never just one person's responsibility. Communication problems may require adjusting to new limitations and possibly ... lead to further loss of communication skills and social isolation. ... with communication problems but pay attention to the way they communicate ...

  20. Two problems in Classical Mechanics

    OpenAIRE

    Rosinger, E. E.

    2004-01-01

    A problem about the present structure of dimensional analysis, and another one about the differences between solids and fluids are suggested. Both problems appear to have certain foundational aspects.

  1. Dental Health and Orthodontic Problems

    Science.gov (United States)

    ... Text Size Email Print Share Dental Health and Orthodontic Problems Page Content Article Body Dental Health Twin ... color can be tinted to match the teeth. Orthodontic Problems Crooked teeth, overbites and underbites are best ...

  2. Eldercare at Home: Mobility Problems

    Science.gov (United States)

    ... dementia, poor eyesight, or need for medication review. Obvious problems with gait and balance (such as a ... condition such as emphysema or infection, a stroke, depression, circulatory problems, or over-medication with sedatives or ...

  3. On the graph turnpike problem

    KAUST Repository

    Feder, Tomás

    2009-06-01

    Results on graph turnpike problem without distinctness, including its NP-completeness, and an O(m+n log n) algorithm, is presented. The usual turnpike problem has all pairwise distances given, but does not specify which pair of vertices w e corresponds to. There are two other problems that can be viewed as special cases of the graph turnpike problem, including the bandwidth problem and the low-distortion graph embedding problem. The aim for the turnpike problem in the NP-complete is to orient the edges with weights w i in either direction so that when the whole cycle is transversed in the real line, it returns to a chosen starting point for the cycle. An instance of the turnpike problem with or without distinctness is uniquely mappable if there exists at most one solution up to translation and choice of orientation.

  4. Problems of high energy physics

    International Nuclear Information System (INIS)

    Some problems of high energy physics are discussed. The main attention is paid to describibg the standard model. The model comprises quantum chromodynamics and electroweak interaction theory. The problem of CP breaking is considered as well. 8 refs.; 1 tab

  5. Direct Problems and Inverse Problems in Biometric Systems

    Directory of Open Access Journals (Sweden)

    Mihailescu Marius Iulian

    2013-10-01

    Full Text Available The article purpose is to describe the two sides of biometrics technologies, direct problems and inverse problems. The advance that we face today in field of Information Technology makes Information Security an inseparable part. The authentication has a huge role when we deal about security. The problems that can appear in implementing and developing biometrics systems is raising many problems, and one of the goal of this article is to focus on direct and inverse problems which is a new and challenging branch in biometrics technologies.

  6. Terrorism and identity problem

    Directory of Open Access Journals (Sweden)

    Šijaković Ivan

    2002-01-01

    Full Text Available Terrorism is phenomenon of modern society, which became expressive especially in second half of twentieth century. There is a real danger that it could increase in growing number of terrorist groups, their aims, arms and ways of work, and that it could effect also in twentieth first century. Terrorism endangers the most important product of modern times: democracy, freedom, and human rights. There are different causes and reasons for existing of terrorist organizations and their cruel terrorist actions. This text analyzes a question of identity as a possible reason for existing of different terrorist groups and organizations and for their actions. Search for identity and question how to defend it create different problems and difficulties for individuals and groups. That identity is one-sided, disported, based on a false faith and so called salvation, but, to defend it somebody is prepared to sacrifice everything, his own life if that is necessary (but frequently somebody else's. That way, terrorism can be understood as a way of defending that identity.

  7. Conceptual Problems in Cosmology

    CERN Document Server

    Vieira, F J Amaral

    2011-01-01

    In this essay a critical review of present conceptual problems in current cosmology is provided from a more philosophical point of view. In essence, a digression on how could philosophy help cosmologists in what is strictly their fundamental endeavor is presented. We start by recalling some examples of enduring confrontations among philosophers and physicists on what could be contributed by the formers to the day-time striving of the second ones. Then, a short review of the standard model Friedmann-Lema\\^itre-Robertson-Walter (FLRW) of cosmology is given. It seems apparent that cosmology is living a golden age with the advent of observations of high precision. Nonetheless, a critical revisiting of the direction in which it should go on appears also needed, for misconcepts like "quantum backgrounds for cosmological classical settings" and "quantum gravity unification" have not been properly constructed up-to-date. Thus, knowledge-building in cosmology, more than in any other field, should begin with visions of...

  8. Inverse Problems of Thermoelectricity

    Science.gov (United States)

    Anatychuk, L. I.; Luste, O. J.; Kuz, R. V.; Strutinsky, M. N.

    2011-05-01

    Classical thermoelectricity is based on the use of the Seebeck and Thomson effects that occur in the near-contact areas between n- and p-type materials. A conceptually different approach to thermoelectric power converter design that is based on the law of thermoelectric induction of currents is also known. The efficiency of this approach has already been demonstrated by its first applications. More than 10 basically new types of thermoelements were discovered with properties that cannot be achieved by thermocouple power converters. Therefore, further development of this concept is of practical interest. This paper provides a classification and theory for solving the inverse problems of thermoelectricity that form the basis for devising new thermoelement types. Computer methods for their solution for anisotropic and inhomogeneous media are elaborated. Regularities related to thermoelectric current excitation in anisotropic and inhomogeneous media are established. The possibility of obtaining eddy currents of a particular configuration through control of the temperature field and material parameters for the creation of new thermo- element types is demonstrated for three-dimensional (3D) models of anisotropic and inhomogeneous media.

  9. Problem Understanding through Landscape Theory

    OpenAIRE

    Chicano, Francisco; Luque, Gabriel; Alba, Enrique

    2013-01-01

    In order to understand the structure of a problem we need to measure some features of the problem. Some examples of measures suggested in the past are autocorrelation and fitness-distance correlation. Landscape theory, developed in the last years in the field of combinatorial optimization, provides mathematical expressions to efficiently compute statistics on optimization problems. In this paper we discuss how can we use optimización combinatoria in the context of problem understanding and pr...

  10. On solving stochastic MADM problems

    OpenAIRE

    Văduva Ion; Resteanu Cornel

    2009-01-01

    The paper examines a MADM problem with stochastic attributes. The transformation of a stochastic MADM problem into a cardinal problem is done by the standardization of the probability distribution of each attribute X and calculating the information of each attribute as Shannon's entropy or Onicescu's informational energy. Some well known (performant) methods to solve a cardinal MADM problem are presented and a method for combining results of several methods to give a final MADM solution is di...

  11. About an optimal visiting problem

    OpenAIRE

    Bagagiolo, Fabio; Benetton, Michela

    2010-01-01

    In this paper we are concerned with the optimal control problem consisting in minimizing the time for reaching (visiting) a fixed number of target sets, in particular more than one target. Such a problem is of course reminiscent of the famous "Traveling Salesman Problem" and brings all its computational diculties. Our aim is to apply the dynamic programming technique in order to characterize the value function of the problem as the unique viscosity solution of a suitable Hamilton-Jacobi equat...

  12. Heuristic methods for messenger problem

    OpenAIRE

    Kobzareva, Maria

    2011-01-01

    This work describes static and dynamic problems with one messenger or multiple number of messengers and suggests a possibility of solving such problems with modified heuristic methods. To solve messenger problem, modified nearest neighbor heuristic, modified insertion heuristic and modified exchange heuristic are used. The main contribution of this work are applications, developed in MS Excel, programmed with Visual Basic for Application, that can solve static and dynamic problems with one me...

  13. Unsolvability Cores in Classification Problems

    OpenAIRE

    Walter, Hermann K. -G.; Brandt, Ulrike

    2014-01-01

    Classification problems have been introduced by M. Ziegler as a generalization of promise problems. In this paper we are concerned with solvability and unsolvability questions with respect to a given set or language family, especially with cores of unsolvability. We generalize the results about unsolvability cores in promise problems to classification problems. Our main results are a characterization of unsolvability cores via cohesiveness and existence theorems for such cores in unsolvable c...

  14. Solving complex fisheries management problems

    DEFF Research Database (Denmark)

    Petter Johnsen, Jahn; Eliasen, Søren Qvist

    2011-01-01

    A crucial issue for the new EU common fisheries policy is how to solve the discard problem. Through a study of the institutional set up and the arrangements for solving the discard problem in Denmark, the Faroe Islands, Iceland and Norway, the article identifies the discard problem as related to...

  15. The Constrained Bottleneck Transportation Problem

    OpenAIRE

    Peerayuth Charnsethikul; Saeree Svetasreni

    2007-01-01

    Two classes of the bottleneck transportation problem with an additional budget constraint are introduced. An exact approach was proposed to solve both problem classes with proofs of correctness and complexity. Moreover, the approach was extended to solve a class of multi-commodity transportation network with a special case of the multi-period constrained bottleneck assignment problem.

  16. Posing Problems from Children's Literature

    Science.gov (United States)

    Young, Elaine; Marroquin, Christine L.

    2006-01-01

    One of the most important principles in reform mathematics is allowing students to be challenged by mathematics problems. The National Council of Teachers of Mathematics (NCTM 2000) has called for changes in the problems that are typically posed to students, asserting that such problems should instead require students to reason, communicate,…

  17. Medical-biological problems

    International Nuclear Information System (INIS)

    The report contains data on operational and emergency staff of the Chernobyl nuclear power plant who were exposed to radiation as a consequence of the reactor accident, the size of the doses received and consequences for health. 203 persons were found to have acute radiation sickness. Of the 22 patients suffering from an extremely severe degree of acute radiation sickness, 19 died. Of the 23 patients with severe bone marrow syndrome, 7 died. For the majority of patients, clinical recovery occurred toward the end of the second month following the accident. The main harmful factor for all victims was the relatively uniform gamma- and beta-radiation effect in a dosage exceeding 1 Gy and, in the case of 35 people exceeding 4 Gy. Radiation damage to wide areas of the skin was one of the main factors contributing to the overall severe condition of the patients, and was a determining factor in the main fatal complications. A preliminary evaluation of the use of some biochemical and immunological tests in the event of accidental exposure to radiation and the methods of treatment and preliminary assessment of their effectiveness are presented. Another part of the report contains data on the doses from radiation exposure to the population of the town of Pripyat' until the time of evacuation and to the population in the 30 km zone around Chernobyl' nuclear power plant and radiation consequences of the accident for the population of different regions in the European part of the USSR, especially the problems related to the contamination of food products. The last part of the report gives some data on the organization of medical examinations of the population from the region around the Chernobyl' plant and on the long-term programmes for the medical and biological monitoring of the population and personnel

  18. Problems in helioseismology

    International Nuclear Information System (INIS)

    The resonant frequencies of solar acoustic-gravity waves are considered as probes of the sun's internal structure and dynamics. A perturbation method for calculating the effects of slow rotation and weak magnetic fields on p-mode frequencies is presented. Distortion of the equilibrium state of the star is taken into account. The method is applied to various hypothetical magnetic field geometries and rotation laws. Asymptotic estimates are developed and compared with the numerical results. The combined effect of rotation and magnetic fields is discussed. Current observations are reviewed in the light of the present results. A simple model is used to investigate the frequencies of high-degree acoustic modes which may be confined to the solar chromosphere. Such modes may be detected in observations from space. It is argued that they could provide a means of determining the mean sound speed in the chromosphere and the location of the transition zone between chromosphere and corona. It has been suggested that the sun could contain in its core quark nuggets which may constitute the ''missing mass''. Solar oscillations provide an extra set of constraints that any solar model must satisfy. Non-standard solar models containing a central black hole and a quark nugget core are constructed. The effect on a combination of resonant p-frequencies sensitive to conditions in the core is calculated by an asymptotic method. A black hole tends to make agreement between theoretical eigenfrequencies and observation worse. A quark nugget core may improve the agreement but tends to make the neutrino problem more acute. (author)

  19. About an Optimal Visiting Problem

    Energy Technology Data Exchange (ETDEWEB)

    Bagagiolo, Fabio, E-mail: bagagiol@science.unitn.it; Benetton, Michela [Unversita di Trento, Dipartimento di Matematica (Italy)

    2012-02-15

    In this paper we are concerned with the optimal control problem consisting in minimizing the time for reaching (visiting) a fixed number of target sets, in particular more than one target. Such a problem is of course reminiscent of the famous 'Traveling Salesman Problem' and brings all its computational difficulties. Our aim is to apply the dynamic programming technique in order to characterize the value function of the problem as the unique viscosity solution of a suitable Hamilton-Jacobi equation. We introduce some 'external' variables, one per target, which keep in memory whether the corresponding target is already visited or not, and we transform the visiting problem in a suitable Mayer problem. This fact allows us to overcome the lacking of the Dynamic Programming Principle for the originary problem. The external variables evolve with a hysteresis law and the Hamilton-Jacobi equation turns out to be discontinuous.

  20. [361 million problems].

    Science.gov (United States)

    Livi Bacci, M

    1990-01-01

    changing from the basic subsistence and energy of Malthus's day, as are the factors of election and adaptation. In an increasingly interdependent world, the link between production and consumption of natural resources has become less obvious, so that signs of dangerous imbalances between population and resources may be overlooked. But the demographic problems of 1 region will increasingly affect all other regions. PMID:12316837

  1. The Association between Attention Problems and Internalizing and Externalizing Problems: The Mediating Role of Peer Problems

    Science.gov (United States)

    Yip, Vania T.; Ang, Rebecca P.; Ooi, Yoon Phaik; Fung, Daniel S. S.; Mehrotra, Kala; Sung, Min; Lim, Choon Guan

    2013-01-01

    Background: The high prevalence of attention problems in children warrants concern, as it is a risk factor for internalizing and externalizing problems. There lies a need to understand possible factors that may mediate this link so that interventions may be targeted to alleviate these mediators and interrupt the link between attention problems and…

  2. Problem based teaching with other focuses than problem solving

    OpenAIRE

    Hansson, Per-Olof; Jansson, Per; Wihlborg, Elin

    2015-01-01

    Problem based teaching has been on the agenda in higher education for at least the last twenty years and is embedded in professional educations often to prepare students for real life problem solving. However, in when higher education rather aim to provide deeper theoretical and reflective competences promoting the students capacities to address unpredictable challenges in different contexts, there might be other ways of applying and using problem based educational tools. In this paper we des...

  3. The problem of time and the problem of quantum measurement

    CERN Document Server

    Singh, Tejinder P

    2012-01-01

    Quantum theory depends on an external classical time, and there ought to exist an equivalent reformulation of the theory which does not depend on such a time. The demand for the existence of such a reformulation suggests that quantum theory is an approximation to a stochastic non-linear theory. The stochastic non-linearity provides a dynamical explanation for the collapse of the wave-function during a quantum measurement. Hence the problem of time and the measurement problem are related to each other: the search for a solution for the former problem naturally implies a solution for the latter problem.

  4. Dimensions of problem based learning

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Lerche; Andreasen, Lars Birch

    2013-01-01

    The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning such...... as the exploration of problems, the project method, online collaboration, and the dialogic nature of students’ working together. A special attention is given to the historical development and theoretical roots of problem-oriented project work in Denmark. The case to be explored will be the Masters...... programme in ICT and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....

  5. Abstract Cauchy problems three approaches

    CERN Document Server

    Melnikova, Irina V

    2001-01-01

    Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

  6. Problem Solving and Complex Systems

    CERN Document Server

    Guinand, Frédéric

    2008-01-01

    The observation and modeling of natural Complex Systems (CSs) like the human nervous system, the evolution or the weather, allows the definition of special abilities and models reusable to solve other problems. For instance, Genetic Algorithms or Ant Colony Optimizations are inspired from natural CSs to solve optimization problems. This paper proposes the use of ant-based systems to solve various problems with a non assessing approach. This means that solutions to some problem are not evaluated. They appear as resultant structures from the activity of the system. Problems are modeled with graphs and such structures are observed directly on these graphs. Problems of Multiple Sequences Alignment and Natural Language Processing are addressed with this approach.

  7. Inverse problem in hydrogeology

    Science.gov (United States)

    Carrera, Jesús; Alcolea, Andrés; Medina, Agustín; Hidalgo, Juan; Slooten, Luit J.

    2005-03-01

    The state of the groundwater inverse problem is synthesized. Emphasis is placed on aquifer characterization, where modelers have to deal with conceptual model uncertainty (notably spatial and temporal variability), scale dependence, many types of unknown parameters (transmissivity, recharge, boundary conditions, etc.), nonlinearity, and often low sensitivity of state variables (typically heads and concentrations) to aquifer properties. Because of these difficulties, calibration cannot be separated from the modeling process, as it is sometimes done in other fields. Instead, it should be viewed as one step in the process of understanding aquifer behavior. In fact, it is shown that actual parameter estimation methods do not differ from each other in the essence, though they may differ in the computational details. It is argued that there is ample room for improvement in groundwater inversion: development of user-friendly codes, accommodation of variability through geostatistics, incorporation of geological information and different types of data (temperature, occurrence and concentration of isotopes, age, etc.), proper accounting of uncertainty, etc. Despite this, even with existing codes, automatic calibration facilitates enormously the task of modeling. Therefore, it is contended that its use should become standard practice. L'état du problème inverse des eaux souterraines est synthétisé. L'accent est placé sur la caractérisation de l'aquifère, où les modélisateurs doivent jouer avec l'incertitude des modèles conceptuels (notamment la variabilité spatiale et temporelle), les facteurs d'échelle, plusieurs inconnues sur différents paramètres (transmissivité, recharge, conditions aux limites, etc.), la non linéarité, et souvent la sensibilité de plusieurs variables d'état (charges hydrauliques, concentrations) des propriétés de l'aquifère. A cause de ces difficultés, le calibrage ne peut êtreséparé du processus de modélisation, comme c'est le

  8. The underinvestment problem under conglomeration

    Directory of Open Access Journals (Sweden)

    Jacques A. Schnabel

    2015-12-01

    Full Text Available This theoretical paper explores whether the underinvestment problem is aggravated or ameliorated by the formation of a pure conglomerate. It establishes that the answer depends critically on the volatility of corporate assets. If volatility is low, conglomeration ameliorates the underinvestment problem, whereas if volatility is high, conglomeration aggravates the underinvestment problem. These analytical results are then invoked as a potential explanation for the ambiguous conclusions of empirical studies that delve into the existence of a conglomerate discount.

  9. Mathematical problems for chemistry students

    CERN Document Server

    Pota, Gyorgy

    2006-01-01

    Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistry students in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialists of the chemistry-related fields (physicists, mathematicians, biologists, etc.) into the world of the chemical applications. Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, other

  10. Active Learning for Matching Problems

    OpenAIRE

    Charlin, Laurent; Zemel, Rich; Boutilier, Craig

    2012-01-01

    Effective learning of user preferences is critical to easing user burden in various types of matching problems. Equally important is active query selection to further reduce the amount of preference information users must provide. We address the problem of active learning of user preferences for matching problems, introducing a novel method for determining probabilistic matchings, and developing several new active learning strategies that are sensitive to the specific matching objective. Expe...

  11. On the job rotation problem

    OpenAIRE

    Lewis, Seth Charles; Butkovic, Peter

    2007-01-01

    The job rotation problem (JRP) is the following: Given an \\(n \\times n\\) matrix \\(A\\) over \\(\\Re \\cup \\{\\ -\\infty\\ \\}\\\\) and \\(k \\leq n\\), find a \\(k \\times k\\) principal submatrix of \\(A\\) whose optimal assignment problem value is maximum. No polynomial algorithm is known for solving this problem if \\(k\\) is an input variable. We analyse JRP and present polynomial solution methods for a number of special cases.

  12. Psychological distress and problem drinking

    OpenAIRE

    Mentzakis, Emmanouil; Roberts, Bayard; Suhrcke, Marc; McKee, Martin

    2015-01-01

    We examine the influence of harmful alcohol use on mental health using a flexible two-step instrumental variables approach and household survey data from nine countries of the former Soviet Union. Using alcohol advertisements to instrument for alcohol, we show that problem drinking has a large detrimental effect on psychological distress, with problem drinkers exhibiting a 42% increase in the number of mental health problems reported and a 15% higher chance of reporting very poor mental healt...

  13. Mathematical problems for chemistry students

    CERN Document Server

    Pota, Gyorgy

    2011-01-01

    Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistrystudents in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialistsof the chemistry-related fields (physicists, mathematicians, biologists, etc.) intothe world of the chemical applications.Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, others we

  14. Solving Public Transit Scheduling Problems

    OpenAIRE

    Mesquita, Marta; Moz, Margarida; Paias, Ana; Paixão, José; Pato, Margarida Vaz; Respício, Ana

    2008-01-01

    Operational planning within public transit companies has been extensively tackled but still remains a challenging area for operations research models and techniques. This phase of the planning process comprises vehicle scheduling, crew scheduling and rostering problems. In this paper, a new integer mathematical formulation to describe the integrated vehicle-crew-rostering problem is presented. The method proposed to solve this multi-objective problem is a sequential algorithm considered withi...

  15. Aspiration Problems in Indian Microfinance

    OpenAIRE

    Wendy Olsen; Jamie Morgan

    2010-01-01

    This article examines the problems that arise from borrowers’ growing aspirations for credit in rural South India. Two core problems arise, conditioned by the class origin of each family: first, a tendency to borrow beyond the capacity to repay, and second, the creation of new gender tensions in which female individualism clashes with traditional male dominance of household decision making. The problem of excess aspirations was first described by Veblen and has been fleshed out in the credi...

  16. Pet Problems at Home: Pet Problems in the Community.

    Science.gov (United States)

    Soltow, Willow

    1984-01-01

    Discusses problems of pets in the community, examining the community's role related to disruptive pets and pet overpopulation. Also discusses pet problems at home, offering advice on selecting a pet, meeting a pet's needs, and disciplining pets. Includes a list of books, films/filmstrips, teaching materials, and various instructional strategies.…

  17. Haplotyping Problem, A Clustering Approach

    International Nuclear Information System (INIS)

    Construction of two haplotypes from a set of Single Nucleotide Polymorphism (SNP) fragments is called haplotype reconstruction problem. One of the most popular computational model for this problem is Minimum Error Correction (MEC). Since MEC is an NP-hard problem, here we propose a novel heuristic algorithm based on clustering analysis in data mining for haplotype reconstruction problem. Based on hamming distance and similarity between two fragments, our iterative algorithm produces two clusters of fragments; then, in each iteration, the algorithm assigns a fragment to one of the clusters. Our results suggest that the algorithm has less reconstruction error rate in comparison with other algorithms

  18. Problem posing reflections and applications

    CERN Document Server

    Brown, Stephen I

    2014-01-01

    As a result of the editors' collaborative teaching at Harvard in the late 1960s, they produced a ground-breaking work -- The Art Of Problem Posing -- which related problem posing strategies to the already popular activity of problem solving. It took the concept of problem posing and created strategies for engaging in that activity as a central theme in mathematics education. Based in part upon that work and also upon a number of articles by its authors, other members of the mathematics education community began to apply and expand upon their ideas. This collection of thirty readings is a tes

  19. The problems of Visaginas town

    International Nuclear Information System (INIS)

    The problems of Visaginas are specific and, first of all, connected with the operation of the Ignalina nuclear power plant and cultural development of Visaginas ethnic minorities, lack of skilled specialists employed in different spheres. Some difficulties we have with the learning of the official language. A strong well-reasoned opinion of the scientists corresponds to our practical directions: the problems of the town of Visaginas are not only the problems of its inhabitants but also a composite part of the problems of the Ignalina nuclear power plant region. (author)

  20. Problem solving through recreational mathematics

    CERN Document Server

    Averbach, Bonnie

    1999-01-01

    Historically, many of the most important mathematical concepts arose from problems that were recreational in origin. This book takes advantage of that fact, using recreational mathematics - problems, puzzles and games - to teach students how to think critically. Encouraging active participation rather than just observation, the book focuses less on mathematical results than on how these results can be applied to thinking about problems and solving them. Each chapter contains a diverse array of problems in such areas as logic, number and graph theory, two-player games of strategy, solitaire ga

  1. A Problem with Current Conceptions of Expert Problem Solving

    CERN Document Server

    Kuo, Eric; Gupta, Ayush; Elby, Andrew

    2011-01-01

    Current conceptions of expert problem solving depict physical/conceptual reasoning and formal mathematical reasoning as separate steps: a good problem solver first translates a physical understanding into mathematics, then performs mathematical/symbolic manipulations, then interprets the mathematical solution physically. However, other research suggests that blending conceptual and symbolic reasoning during symbolic manipulations can reflect expertise. We explore the hypothesis that blending conceptual and symbolic reasoning (i) indicates problem-solving expertise more than adherence to "expert" problem-solving steps and (ii) is something some undergraduates do spontaneously, suggesting it's a feasible instructional target. Interviewed students were asked to (1) explain a particular equation and (2) solve a problem using that equation. In-depth analysis of two students, Alex and Pat, revealed a pattern of behavior. All 11 interviews were coded to investigate the generalizability of this pattern. Alex describe...

  2. Students' Problem Solving and Justification

    Science.gov (United States)

    Glass, Barbara; Maher, Carolyn A.

    2004-01-01

    This paper reports on methods of students' justifications of their solution to a problem in the area of combinatorics. From the analysis of the problem solving of 150 students in a variety of settings from high-school to graduate study, four major forms of reasoning evolved: (1) Justification by Cases, (2) Inductive Argument, (3) Elimination…

  3. Problem-Oriented Project Work

    DEFF Research Database (Denmark)

    Olsen, Poul Bitsch; Pedersen, Nils Kaare

    This book is meant to support problem-oriented learning activities. Problem-orientation concerns the reasoning about lack of knowledge, while project work includes the ethnomethods that are practiced when collectives produce scientific knowledge. This book reflects particular methods related...

  4. Reactor physics problems on HCPWR

    International Nuclear Information System (INIS)

    Reactor physics problems on high conversion pressurized water reactors (HCPWRs) are discussed. Described in this report are outline of the HCPWR, expected accuracy for the various reactor physical qualities, and method for K-effective calculation in the resonance energy area. And requested further research problems are shown. The target value of the conversion ratio are also discussed. (author)

  5. Problem Solving through Paper Folding

    Science.gov (United States)

    Wares, Arsalan

    2014-01-01

    The purpose of this article is to describe a couple of challenging mathematical problems that involve paper folding. These problem-solving tasks can be used to foster geometric and algebraic thinking among students. The context of paper folding makes some of the abstract mathematical ideas involved relatively concrete. When implemented…

  6. Analysis of a Pendulum Problem

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1998-01-01

    The ball-balancer, or cart-ball system, demonstrates some basic concepts in control being nonlinear, multivariable, and non-minimum phase. It is basically an inverted pendulum problem, which is a much used benchmark problem. The objective here is to provide an analysis of the system, which can be...

  7. Sinopec Tests Find No Problems

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Sinopec gas defended the quality of its liquefied petroleum gas(LPG)by announcing the results of independent tests in early February,following allegations by drivers that their vehicles had problems after filling their tanks at Sinopec petrol stations.Its first media briefing over the suspected engine-stalling problem of its product,Sinopec(Hong Kong)Petrol Filling Station Co.

  8. Simon on Problem-Solving

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai

    general approach to problem solving. We apply these Simonian ideas to organizational issues, specifically new organizational forms. Specifically, Simonian ideas allow us to develop a morphology of new organizational forms and to point to some design problems that characterize these forms.Keywords: Herbert...

  9. Introduction to global energetic problems

    International Nuclear Information System (INIS)

    This book gives a view on global energetic problems and proposes a thorough economic analysis on principle aspects taken into account: energy supply, depending energy sources and available technologic channels, relationships between macro-economy and energy demand, new size of energy problems (environmental effects, overcosts of renewable energy sources, necessity of an high technologic development...). 38 refs

  10. A Problem on Optimal Transportation

    Science.gov (United States)

    Cechlarova, Katarina

    2005-01-01

    Mathematical optimization problems are not typical in the classical curriculum of mathematics. In this paper we show how several generalizations of an easy problem on optimal transportation were solved by gifted secondary school pupils in a correspondence mathematical seminar, how they can be used in university courses of linear programming and…

  11. Ruin problems and tail asymptotics

    DEFF Research Database (Denmark)

    Rønn-Nielsen, Anders

    The thesis Ruin Problems and Tail Asymptotics provides results on ruin problems for several classes of Markov processes. For a class of diffusion processes with jumps an explicit expression for the joint Laplace transform of the first passage time and the corresponding undershoot is derived. An...

  12. Traveling Salesman Problem with Transportation

    Directory of Open Access Journals (Sweden)

    Valeriu Ungureanu

    2006-09-01

    Full Text Available Traveling Salesman Problem (TSP is a generic name that includes diverse practical models. Motivated by applications, a new model of TSP is examined – a synthesis of classical TSP and classical Transportation Problem. Algorithms based on Integer Programming cutting-plane methods and Branch and Bound Techniques are obvious.

  13. Geothermal Energy: Prospects and Problems

    Science.gov (United States)

    Ritter, William W.

    1973-01-01

    An examination of geothermal energy as a means of increasing the United States power resources with minimal pollution problems. Developed and planned geothermal-electric power installations around the world, capacities, installation dates, etc., are reviewed. Environmental impact, problems, etc. are discussed. (LK)

  14. Vibrations and Stability: Solved Problems

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    Worked out solutions for exercise problems in J. J. Thomsen 'Vibrations and Stability: Advanced Theory, Analysis, and Tools', Springer, Berlin - Heidelberg, 2003.......Worked out solutions for exercise problems in J. J. Thomsen 'Vibrations and Stability: Advanced Theory, Analysis, and Tools', Springer, Berlin - Heidelberg, 2003....

  15. Learning Impasses in Problem Solving

    Science.gov (United States)

    Hodgson, J. P. E.

    1992-01-01

    Problem Solving systems customarily use backtracking to deal with obstacles that they encounter in the course of trying to solve a problem. This paper outlines an approach in which the possible obstacles are investigated prior to the search for a solution. This provides a solution strategy that avoids backtracking.

  16. Solving the drift control problem

    Directory of Open Access Journals (Sweden)

    Melda Ormeci Matoglu

    2015-12-01

    Full Text Available We model the problem of managing capacity in a build-to-order environment as a Brownian drift control problem. We formulate a structured linear program that models a practical discretization of the problem and exploit a strong relationship between relative value functions and dual solutions to develop a functional lower bound for the continuous problem from a dual solution to the discrete problem. Refining the discretization proves a functional strong duality for the continuous problem. The linear programming formulation is so badly scaled, however, that solving it is beyond the capabilities of standard solvers. By demonstrating the equivalence between strongly feasible bases and deterministic unichain policies, we combinatorialize the pivoting process and by exploiting the relationship between dual solutions and relative value functions, develop a mechanism for solving the LP without ever computing its coefficients. Finally, we exploit the relationship between relative value functions and dual solutions to develop a scheme analogous to column generation for refining the discretization so as to drive the gap between the discrete approximation and the continuous problem to zero quickly while keeping the LP small. Computational studies show our scheme is much faster than simply solving a regular discretization of the problem both in terms of finding a policy with a low average cost and in terms of providing a lower bound on the optimal average cost.

  17. Subspace Methods for Eigenvalue Problems

    NARCIS (Netherlands)

    Hochstenbach, Michiel Erik

    2003-01-01

    This thesis treats a number of aspects of subspace methods for various eigenvalue problems. Vibrations and their corresponding eigenvalues (or frequencies) arise in science, engineering, and daily life. Matrix eigenvalue problems come from a large number of areas, such as chemistry, mechanics, dyn

  18. Non-Euclidean Visibility Problems

    Indian Academy of Sciences (India)

    Fernando Chamizo

    2006-05-01

    We consider the analog of visibility problems in hyperbolic plane (represented by Poincaré half-plane model $\\mathbb{H}$), replacing the standard lattice $\\mathbb{Z} × \\mathbb{Z}$ by the orbit = under the full modular group $SL_2(\\mathbb{Z})$. We prove a visibility criterion and study orchard problem and the cardinality of visible points in large circles.

  19. Heuristics for Multidimensional Packing Problems

    DEFF Research Database (Denmark)

    Egeblad, Jens

    minimum height container required for the items. The main contributions of the thesis are three new heuristics for strip-packing and knapsack packing problems where items are both rectangular and irregular. In the two first papers we describe a heuristic for the multidimensional strip-packing problem that...... results of this heuristic are among the best published in the literature both for two- and three-dimensional strip-packing problems for irregular shapes. In the third paper, we introduce a heuristic for two- and three-dimensional rectangular knapsack packing problems. The two-dimensional heuristic uses...... promising. A heuristic for a three-dimensional knapsack packing problem involving furniture is presented in the fourth paper. The heuristic is based on a variety of techniques including tree-search, wall-building, and sequential placement. The solution process includes considerations regarding stability and...

  20. Methods of solving nonstandard problems

    CERN Document Server

    Grigorieva, Ellina

    2015-01-01

    This book, written by an accomplished female mathematician, is the second to explore nonstandard mathematical problems – those that are not directly solved by standard mathematical methods but instead rely on insight and the synthesis of a variety of mathematical ideas.   It promotes mental activity as well as greater mathematical skills, and is an ideal resource for successful preparation for the mathematics Olympiad. Numerous strategies and techniques are presented that can be used to solve intriguing and challenging problems of the type often found in competitions.  The author uses a friendly, non-intimidating approach to emphasize connections between different fields of mathematics and often proposes several different ways to attack the same problem.  Topics covered include functions and their properties, polynomials, trigonometric and transcendental equations and inequalities, optimization, differential equations, nonlinear systems, and word problems.   Over 360 problems are included with hints, ...

  1. The three-body problem

    International Nuclear Information System (INIS)

    The three-body problem, which describes three masses interacting through Newtonian gravity without any restrictions imposed on the initial positions and velocities of these masses, has attracted the attention of many scientists for more than 300 years. In this paper, we present a review of the three-body problem in the context of both historical and modern developments. We describe the general and restricted (circular and elliptic) three-body problems, different analytical and numerical methods of finding solutions, methods for performing stability analysis and searching for periodic orbits and resonances. We apply the results to some interesting problems of celestial mechanics. We also provide a brief presentation of the general and restricted relativistic three-body problems, and discuss their astronomical applications. (review article)

  2. Multiscale Modelling and Inverse Problems

    CERN Document Server

    Nolen, J; Stuart, A M

    2010-01-01

    The need to blend observational data and mathematical models arises in many applications and leads naturally to inverse problems. Parameters appearing in the model, such as constitutive tensors, initial conditions, boundary conditions, and forcing can be estimated on the basis of observed data. The resulting inverse problems are often ill-posed and some form of regularization is required. These notes discuss parameter estimation in situations where the unknown parameters vary across multiple scales. We illustrate the main ideas using a simple model for groundwater flow. We will highlight various approaches to regularization for inverse problems, including Tikhonov and Bayesian methods. We illustrate three ideas that arise when considering inverse problems in the multiscale context. The first idea is that the choice of space or set in which to seek the solution to the inverse problem is intimately related to whether a homogenized or full multiscale solution is required. This is a choice of regularization. The ...

  3. Math word problems for dummies

    CERN Document Server

    Sterling, Mary Jane

    2008-01-01

    Covers percentages, probability, proportions, and moreGet a grip on all types of word problems by applying them to real lifeAre you mystified by math word problems? This easy-to-understand guide shows you how to conquer these tricky questions with a step-by-step plan for finding the right solution each and every time, no matter the kind or level of problem. From learning math lingo and performing operations to calculating formulas and writing equations, you''ll get all the skills you need to succeed!Discover how to: * Translate word problems into plain English* Brush up on basic math skills* Plug in the right operation or formula* Tackle algebraic and geometric problems* Check your answers to see if they work

  4. VHTRC temperature coefficient benchmark problem

    International Nuclear Information System (INIS)

    As an activity of IAEA Coordinated Research Programme, a benchmark problem is proposed for verifications of neutronic calculation codes for a low enriched uranium fuel high temperature gas-cooled reactor. Two problems are given on the base of heating experiments at the VHTRC which is a pin-in-block type core critical assembly loaded mainly with 4% enriched uranium coated particle fuel. One problem, VH1-HP, asks to calculate temperature coefficient of reactivity from the subcritical reactivity values at five temperature steps between an room temperature where the assembly is nearly at critical state and 200degC. The other problem, VH1-HC, asks to calculate the effective multiplication factor of nearly critical loading cores at the room temperature and 200degC. Both problems further ask to calculate cell parameters such as migration area and spectral indices. Experimental results corresponding to main calculation items are also listed for comparison. (author)

  5. Spreadsheet modelling for solving combinatorial problems: The vendor selection problem

    CERN Document Server

    Ipsilandis, Pandelis G

    2008-01-01

    Spreadsheets have grown up and became very powerful and easy to use tools in applying analytical techniques for solving business problems. Operations managers, production managers, planners and schedulers can work with them in developing solid and practical Do-It-Yourself Decision Support Systems. Small and Medium size organizations, can apply OR methodologies without the presence of specialized software and trained personnel, which in many cases cannot afford anyway. This paper examines an efficient approach in solving combinatorial programming problems with the use of spreadsheets. A practical application, which demonstrates the approach, concerns the development of a spreadsheet-based DSS for the Multi Item Procurement Problem with Fixed Vendor Cost. The DSS has been build using exclusively standard spreadsheet feature and can solve real problems of substantial size. The benefits and limitations of the approach are also discussed.

  6. The \\infty eigenvalue problem and a problem of optimal transportation

    OpenAIRE

    Champion, Thierry; De Pascale, Luigi; Jimenez, Chloé

    2008-01-01

    The so-called eigenvalues and eigenfunctions of the infinite Laplacian $\\Delta_\\infty$ are defined through an asymptotic study of that of the usual $p$-Laplacian $\\Delta_p$, this brings to a characterization via a non-linear eigenvalue problem for a PDE satisfied in the viscosity sense. In this paper, we obtain an other characterization of the first eigenvalue via a problem of optimal transportation, and recover properties of the first eigenvalue and corresponding positive eigenfunctions.

  7. Factorization, Riemann-Hilbert problems and the corona problem

    CERN Document Server

    Camara, M C; Karlovich, Yu I; Spitkovsky, I M

    2011-01-01

    The solvability of the Riemann-Hilbert boundary value problem on the real line is described in the case when its matrix coefficient admits a Wiener-Hopf type factorization with bounded outer factors but rather general diagonal elements of its middle factor. This covers, in particular, the almost periodic setting. Connections with the corona problem are discussed. Based on those, constructive factorization criteria are derived for several types of triangular 2-by-2 matrices.

  8. Optimization and geophysical inverse problems

    Energy Technology Data Exchange (ETDEWEB)

    Barhen, J.; Berryman, J.G.; Borcea, L.; Dennis, J.; de Groot-Hedlin, C.; Gilbert, F.; Gill, P.; Heinkenschloss, M.; Johnson, L.; McEvilly, T.; More, J.; Newman, G.; Oldenburg, D.; Parker, P.; Porto, B.; Sen, M.; Torczon, V.; Vasco, D.; Woodward, N.B.

    2000-10-01

    A fundamental part of geophysics is to make inferences about the interior of the earth on the basis of data collected at or near the surface of the earth. In almost all cases these measured data are only indirectly related to the properties of the earth that are of interest, so an inverse problem must be solved in order to obtain estimates of the physical properties within the earth. In February of 1999 the U.S. Department of Energy sponsored a workshop that was intended to examine the methods currently being used to solve geophysical inverse problems and to consider what new approaches should be explored in the future. The interdisciplinary area between inverse problems in geophysics and optimization methods in mathematics was specifically targeted as one where an interchange of ideas was likely to be fruitful. Thus about half of the participants were actively involved in solving geophysical inverse problems and about half were actively involved in research on general optimization methods. This report presents some of the topics that were explored at the workshop and the conclusions that were reached. In general, the objective of a geophysical inverse problem is to find an earth model, described by a set of physical parameters, that is consistent with the observational data. It is usually assumed that the forward problem, that of calculating simulated data for an earth model, is well enough understood so that reasonably accurate synthetic data can be generated for an arbitrary model. The inverse problem is then posed as an optimization problem, where the function to be optimized is variously called the objective function, misfit function, or fitness function. The objective function is typically some measure of the difference between observational data and synthetic data calculated for a trial model. However, because of incomplete and inaccurate data, the objective function often incorporates some additional form of regularization, such as a measure of smoothness

  9. Periodically specified satisfiability problems: An alternative to domino problems

    Energy Technology Data Exchange (ETDEWEB)

    Marathe, M.V.; Rosenkrantz, D.J.; Stearns, R.E. [Univ. at Albany - SUNY, NY (United States). Dept. of Computer Science] [and others

    1997-02-01

    The authors characterize the complexities of several basic generalized CNF satisfiability problems SAT(S), when instances are specified using various kinds of 1- and 2-dimensional periodic specifications. They outline how this characterization can be used to prove a number of new hardness results for the complexity classes DSPACE(n), NSPACE(n), DEXPTIME, NEXPTIME, EXPSPACE etc. The hardness results presented significantly extend the known hardness results for periodically specified problems. Several advantages are outlined of the use of periodically specified satisfiability problems over the use of domino problems in proving both hardness and easiness results. As one corollary, the authors show that a number of basic NP-hard problems become EXPSPACE-hard when inputs are represented using 1-dimensional infinite periodic wide specifications. This answers a long standing open question posed by Orlin. The results can also be used as starting points for proving the hardness of a number of combinatorial problems when instances are specified succinctly using various succinct specifications. These results significantly extend the results of earlier research in this area.

  10. Problems of multiphase fluid filtration

    CERN Document Server

    Konovalov, AN

    1994-01-01

    This book deals with a spectrum of problems related to the mathematical modeling of multiphase filtration. Emphasis is placed on an inseparable triad: model - algorithm - computer code. An analysis of new and traditional filtration problems from the point of view of both their numerical implementation and the reproduction of one or another technological characteristics of the processes under consideration is given. The basic principles which underlie the construction of efficient numerical methods taking into account the filtration problems are discussed: non-evolutionary nature, degeneration,

  11. Parameter estimation and inverse problems

    CERN Document Server

    Aster, Richard C; Thurber, Clifford H

    2011-01-01

    Parameter Estimation and Inverse Problems, 2e provides geoscience students and professionals with answers to common questions like how one can derive a physical model from a finite set of observations containing errors, and how one may determine the quality of such a model. This book takes on these fundamental and challenging problems, introducing students and professionals to the broad range of approaches that lie in the realm of inverse theory. The authors present both the underlying theory and practical algorithms for solving inverse problems. The authors' treatment is approp

  12. Imbalance problem in community detection

    Science.gov (United States)

    Sun, Peng Gang

    2016-09-01

    Community detection gives us a simple way to understand complex networks' structures. However, there is an imbalance problem in community detection. This paper first introduces the imbalance problem and then proposes a new measure to alleviate the imbalance problem. In addition, we study two variants of the measure and further analyze the resolution scale of community detection. Finally, we compare our approach with some state of the art methods on random networks as well as real-world networks for community detection. Both the theoretical analysis and the experimental results show that our approach achieves better performance for community detection. We also find that our approach tends to separate densely connected subgroups preferentially.

  13. Progressive problems higher grade physics

    CERN Document Server

    Kennedy, William

    2001-01-01

    This book fully covers all three Units studied in Scotland's Higher Grade Physics course, providing a systematic array of problems (from the simplest to the most difficult) to lead variously abled pupils to examination success.

  14. Surrogate Guderley Test Problem Definition

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, Scott D. [Los Alamos National Laboratory; Shashkov, Mikhail J. [Los Alamos National Laboratory

    2012-07-06

    The surrogate Guderley problem (SGP) is a 'spherical shock tube' (or 'spherical driven implosion') designed to ease the notoriously subtle initialization of the true Guderley problem, while still maintaining a high degree of fidelity. In this problem (similar to the Guderley problem), an infinitely strong shock wave forms and converges in one-dimensional (1D) cylindrical or spherical symmetry through a polytropic gas with arbitrary adiabatic index {gamma}, uniform density {rho}{sub 0}, zero velocity, and negligible pre-shock pressure and specific internal energy (SIE). This shock proceeds to focus on the point or axis of symmetry at r = 0 (resulting in ostensibly infinite pressure, velocity, etc.) and reflect back out into the incoming perturbed gas.

  15. The Mind-Body Problem.

    Science.gov (United States)

    Fodor, Jerry A.

    1981-01-01

    Describes several different philosophies of mind with each philosophy's explanation of the mind-body problem. Philosophies discussed include dualism, materialism, functionalism, radical behaviorism, logical behaviorism and central-state identity. (DS)

  16. Enteral nutrition - child - managing problems

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000164.htm Enteral nutrition - child - managing problems To use the sharing features ... trouble breathing, call 911. References Mcclave SA. Enteral nutrition. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  17. Fuel cells: Problems and prospects

    OpenAIRE

    Shukla, AK; Ramesh, KV; Kannan, AM

    1986-01-01

    n recent years, fuel cell technology has advanced significantly. Field trials on certain types of fuel cells have shown promise for electrical use. This article reviews the electrochemistry, problems and prospects of fuel cell systems.

  18. On Generalized Vector Equilibrium Problems

    Institute of Scientific and Technical Information of China (English)

    An-hua Wan; Jun-yi Fu; Wei-hua Mao

    2006-01-01

    A new generalized vector equilibrium problem involving set-valued mappings and the proper quasi-concavity of set-valued mappings in topological vector spaces are introduced; its existence theorems and the convexity of the solution sets are established.

  19. The three-body problem

    CERN Document Server

    Musielak, Z E

    2015-01-01

    The three-body problem, which describes three masses interacting through Newtonian gravity without any restrictions imposed on the initial positions and velocities of these masses, has attracted the attention of many scientists for more than 300 years. In this paper, we present a review of the three-body problem in the context of both historical and modern developments. We describe the general and restricted (circular and elliptic) three-body problems, different analytical and numerical methods of finding solutions, methods for performing stability analysis, search for periodic orbits and resonances, and application of the results to some interesting astronomical and space dynamical settings. We also provide a brief presentation of the general and restricted relativistic three-body problems, and discuss their astronomical applications.

  20. Statistical perspectives on inverse problems

    DEFF Research Database (Denmark)

    Andersen, Kim Emil

    interior of an object from electrical boundary measurements. One part of this thesis concerns statistical approaches for solving, possibly non-linear, inverse problems. Thus inverse problems are recasted in a form suitable for statistical inference. In particular, a Bayesian approach for regularisation is...... obtained by assuming that the a priori beliefs about the solution before having observed any data can be described by a prior distribution. The solution to the statistical inverse problem is then given by the posterior distribution obtained by Bayes' formula. Hence the solution of an ill-posed inverse...... problem is given in terms of probability distributions. Posterior inference is obtained by Markov chain Monte Carlo methods and new, powerful simulation techniques based on e.g. coupled Markov chains and simulated tempering is developed to improve the computational efficiency of the overall simulation...

  1. COPD and other health problems

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000701.htm COPD and other health problems To use the sharing ... diabetes, and high blood pressure. Staying Healthy With COPD Work closely with your doctor to keep COPD ...

  2. Uncapacitated facility location problems: contributions

    Directory of Open Access Journals (Sweden)

    Galvão Roberto Diéguez

    2004-01-01

    Full Text Available The objective of the present paper is to review my personal contributions in the field of uncapacitated facility location problems. These contributions took place throughout my academic career, from the time I was a Ph.D. student at Imperial College to the present day. They cover approximately 30 years, from 1973 to 2003; they address: algorithms developed for the p-median problem and for a general formulation of uncapacitated location problems; the study of dynamic location models; covering and hierarchical location problems; queuing-based probabilistic location models. The contributions encompass theoretical developments, computational algorithms and practical applications. All work took place in an academic environment, with the invaluable collaboration of colleagues (both in Brazil and abroad and research students at COPPE. Each section in the paper is dedicated to a topic that involves a personal contribution. Every one of them is placed within the context of the existing literature.

  3. Integral equations and computation problems

    International Nuclear Information System (INIS)

    Volterra's Integral Equations and Fredholm's Integral Equations of the second kind are discussed. Computational problems are found in the derivations and the computations. The theorem of the solution of the Fredholm's Integral Equation is discussed in detail. (author)

  4. Eldercare at Home: Memory Problems

    Science.gov (United States)

    ... parties. Use reminding strategies. When memory loss is obvious, try these reminding techniques: Encourage carrying a memo ... problem was due to a physical illness or depression, treatment is likely to improve memory. There are ...

  5. Labour force survey: methodological problems

    OpenAIRE

    Bokun, N. C.

    2013-01-01

    The main principles, characteristics and problems of Labour Force Survey (LFS), conducted by the State Statistics of Belarus are considered. The purposes, sampling plan, sample design, data collection mode, the methods of estimation are analyzed.

  6. Parameter estimation and inverse problems

    CERN Document Server

    Aster, Richard C; Thurber, Clifford H

    2005-01-01

    Parameter Estimation and Inverse Problems primarily serves as a textbook for advanced undergraduate and introductory graduate courses. Class notes have been developed and reside on the World Wide Web for faciliting use and feedback by teaching colleagues. The authors'' treatment promotes an understanding of fundamental and practical issus associated with parameter fitting and inverse problems including basic theory of inverse problems, statistical issues, computational issues, and an understanding of how to analyze the success and limitations of solutions to these probles. The text is also a practical resource for general students and professional researchers, where techniques and concepts can be readily picked up on a chapter-by-chapter basis.Parameter Estimation and Inverse Problems is structured around a course at New Mexico Tech and is designed to be accessible to typical graduate students in the physical sciences who may not have an extensive mathematical background. It is accompanied by a Web site that...

  7. Who matters in coordination problems?

    Czech Academy of Sciences Publication Activity Database

    Sákovics, J.; Steiner, Jakub

    2012-01-01

    Roč. 102, č. 7 (2012), s. 3439-3461. ISSN 0002-8282 Institutional support: RVO:67985998 Keywords : coordination problems * heterogeneous agents Subject RIV: AH - Economics Impact factor: 2.792, year: 2012

  8. Commitment Problems in Conflict Resolution

    OpenAIRE

    Kimbrough, Erik; Rubin, Jared; Sheremeta, Roman; Shields, Timothy

    2015-01-01

    Commitment problems are inherent to non-binding conflict resolution mechanisms, since an unsatisfied party can ignore the resolution and initiate conflict. We provide experimental evidence suggesting that even in the absence of binding contractual agreements individuals often avoid conflict by committing to the outcome of a conflict resolution mechanism. Commitment problems are mitigated to a greater extent for groups that opt-in to the conflict resolution mechanism, but only when opting-in i...

  9. COUNTERFEIT DRUGS: PROBLEMS AND SOLUTIONS

    OpenAIRE

    Khanna Surabhi; Nasa Atul; Garg Arun

    2010-01-01

    The pharmaceutical industry is under extraordinary strain. Facing the wrath of consumers because of the cost of products, constantly answering the questions of state and federal legislators looking to control health care costs, and losing value in the marketplace, the industry’s hands are more than full. A less discussed but substantial problem impacts all of pharmaceutical industry’s other problems, counterfeiting. The World Health Organization estimates that counterfeit drugs make up about ...

  10. The Minimum Expectation Selection Problem

    OpenAIRE

    Eppstein, David; Lueker, George

    2001-01-01

    We define the min-min expectation selection problem (resp. max-min expectation selection problem) to be that of selecting k out of n given discrete probability distributions, to minimize (resp. maximize) the expectation of the minimum value resulting when independent random variables are drawn from the selected distributions. We assume each distribution has finitely many atoms. Let d be the number of distinct values in the support of the distributions. We show that if d is a constant greater ...

  11. COINCIDENCE PROBLEMS FOR GENERALIZED CONTRACTIONS

    Directory of Open Access Journals (Sweden)

    Jesús Garcia Falset

    2014-03-01

    Full Text Available In this paper, we establish some new existence, uniqueness and Ulam-Hyers stability theorems for coincidence problems for two single-valued mappings. The main results of this paper extend the results presented in {\\sc O. Mle\\c sni\\c te:} \\emph{Existence and Ulam-Hyers stability results for coincidence problems}, J. Nonlinear Sci.\\ Appl., \\textbf{6} (2013, 108--116. In the last section two examples of application of these results are also given.

  12. The continuation inverse problem revisited

    Science.gov (United States)

    Huestis, Stephen P.

    1998-06-01

    The non-uniqueness of the continuation of a finite collection of harmonic potential field data to a level surface in the source-free region forces its treatment as an inverse problem. A formalism is proposed for the construction of continuation functions which are extremal by various measures. The problem is cast in such a form that the inverse problem solution is the potential function on the lowest horizontal surface above all sources, serving as the boundary function for the Dirichlet problem in the upper half-plane. The desired continuation, at the higher level of interest, must then be in the range of the upward continuation operator acting on this boundary function, rather than being allowed the full freedom of itself being part of a Dirichlet problem boundary function. Extremal solutions minimize non-linear functionals of the continuation function, which are re-expressed as different functionals of the boundary function. A crux of the method is that there is no essential distinction between the upward and downward continuation inverse problems to levels above or below data locations. Casting the optimization as a Lagrange multiplier problem leads to an integral equation for the boundary function, which is readily solved in the Fourier domain for a certain class of functionals. The desired extremal continuation is then given by upward continuation. It is found that for some functionals, application of the Lagrange multiplier theorem requires a further restriction on the set of allowable boundary functions: bandlimitedness is a natural choice for the continuation problem. With this imposition, the theory is developed in detail for semi-norm functionals penalizing departure from a constant potential, in the 2-norm and Sobelev norm senses, and illustrated by application for a small synthetic Deep Tow magnetic field data set.

  13. MULITIGRID METHODS FOR OBSTACLE PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Carsten Gr(a)ser; Ralf Kornhuber

    2009-01-01

    In this review,we intend to clarify the underlying ideas and the relations between various multigrid methods ranging from subset decomposition,to projected subspace decomposition and truncated multigrid.In addition,we present a novel globally convergent inexact active set method which is closely related to truncated multigrid.The numerical properties of algorithms are carefully assessed by means of a degenerate problem and a problem with a complicated coincidence set.

  14. Multi-market trading problem

    Czech Academy of Sciences Publication Activity Database

    Zeman, Jan

    Praha : ÚTIA AV ČR, v.v.i, 2010. s. 43-43. [6th international workshop on Data - Algorithm - Decision making. 02.12.2010-04.12.2010, Jindřichův Hradec] Institutional research plan: CEZ:AV0Z10750506 Keywords : multiple participants * trading problem Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2010/AS/zeman-multi- market trading problem.pdf

  15. The problem of Newton dynamics

    International Nuclear Information System (INIS)

    The problem of the teaching of Newton's principles of dynamics at High School level is addressed. Some usages, reasoning and wording, are pointed as the responsible for the deficient results which are revealed in the background of the first year University students in Physics. A methodology based on simplifying the common vocabulary is proposed in order to provide to the students with a clearer view of the dynamic problems. Some typical examples are shown which illustrate the proposal. (Author)

  16. Claim problems and egalitarian criteria

    OpenAIRE

    Arin, Javier; Benito Ostolaza, Juan Miguel

    2010-01-01

    The paper presents a unified framework where claim and cost sharing problems are jointly analyzed. Both problems have the following common characteristic: given a proposal the agents valuate the suitability of the proposal in two ways, checking how much they loss and how much they gain. Taking this into account, we construct the vector of awards and losses for any proposal and we use different egalitarian criteria to select among these vectors. We use the Lorenz, the Least Square and the lexi...

  17. Diabetes and Sexual and Urologic Problems

    Science.gov (United States)

    ... Disease, and Other Dental Problems Diabetic Eye Disease Diabetes and Sexual and Urologic Problems Troublesome bladder symptoms ... early onset of these sexual and urologic problems. Diabetes and Sexual Problems Both men and women with ...

  18. Prior sleep problems predict internalising problems later in life.

    OpenAIRE

    Touchette, Evelyne; Chollet, Aude; Galéra, Cédric; Fombonne, Eric; Falissard, Bruno; Boivin, Michel; Melchior, Maria

    2012-01-01

    BACKGROUND: One possible risk marker of later internalising symptoms is poor sleep, which is a problem for up to 40% of children. The present study investigated whether prior sleep problems could predict internalising symptoms over a period of 18 years of follow-up. METHODS: The study sample included 1503 French young adults from the TEMPO cohort (mean age=28.8±3.6 years) whose parents participate in the GAZEL cohort study. All TEMPO participants previously took part in a study of children's ...

  19. Ten Problems in Experimental Mathematics

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal; Weisstein, Eric

    2004-09-30

    This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.

  20. Cognitive Problems (Disorientation, Perception, Attention, Learning and Problem-Solving)

    Science.gov (United States)

    ... left side of the brain controls language. The left side of the brain controls the right side of the body. So, language problems are ... such as judging depth, size and distance. The right side of the brain controls the left side of the body. Persons with left-sided ...

  1. Problem Solvers: Problem--Area beyond the Formula

    Science.gov (United States)

    Dean, Chrystal

    2014-01-01

    In this article, associate professor Chrystal Dean describes how teachers can challenge their upper elementary students' understanding of area beyond a memorized formula. Herein she describes an activity that will show students the "why" behind using A = l × w to solve rectangular area problems. The activity will help deepen…

  2. The Problem of Assessing Problem Solving: Can Comparative Judgement Help?

    Science.gov (United States)

    Jones, Ian; Inglis, Matthew

    2015-01-01

    School mathematics examination papers are typically dominated by short, structured items that fail to assess sustained reasoning or problem solving. A contributory factor to this situation is the need for student work to be marked reliably by a large number of markers of varied experience and competence. We report a study that tested an…

  3. Nuclear power engineering problems as the political and economical problems

    International Nuclear Information System (INIS)

    The political and economic aspects of nuclear power engineering status in the countries of the former USSR nowadays are considered. The factors, which lead to the nuclear power crisis, are analyzed. It is shown that the state monopoly for developing the problems of nuclear power engineering and NPP operation plays the main part. The ways for possible crisis overcoming are suggested

  4. Problem-oriented project studies

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Lerche; Danielsen, Oluf

    2010-01-01

    This contribution focuses on 'problem based learning' (however we prefer the notion of ‘problem-oriented project studies’) and the role of the teacher in such a context. The classic traditional role as an expert deciding the curriculum, providing lectures and seminars, giving assignments and...... marking papers / essays is complemented and in some way overruled by a new role as supervisor and facilitator for the group of students working with a research problem, they themselves have picked. However different dimensions of this new teacher role can be seen – from expert in an academic field (result-oriented...... focusing on how the final product demonstrates the students’ ‘correct’ way to handle the academic aspects of the subject in mind) to a role more focusing on processes, methodological dimensions and stressing the importance of a reflexive approach. Some teachers may even tend to take on a role of a...

  5. Java problem-based learning

    Directory of Open Access Journals (Sweden)

    Goran P, Šimić

    2012-01-01

    Full Text Available The paper describes the self-directed problem-based learning system (PBL named Java PBL. The expert module is the kernel of Java PBL. It involves a specific domain model, a problem generator and a solution generator. The overall system architecture is represented in the paper. Java PBL can act as the stand-alone system, but it is also designed to provide support to learning management systems (LMSs. This is provided by a modular design of the system. An LMS can offer the declarative knowledge only. Java PBL offers the procedural knowledge and the progress of the learner programming skills. The free navigation, unlimited numbers of problems and recommendations represent the main pedagogical strategies and tactics implemented into the system.

  6. Topology optimization of flow problems

    DEFF Research Database (Denmark)

    Gersborg, Allan Roulund

    2007-01-01

    This thesis investigates how to apply topology optimization using the material distribution technique to steady-state viscous incompressible flow problems. The target design applications are fluid devices that are optimized with respect to minimizing the energy loss, characteristic properties of...... dominated transport in 2D Stokes flow. Using Stokes flow limits the range of applications; nonetheless, the thesis gives a proof-of-concept for the application of the method within fluid dynamic problems and it remains of interest for the design of microfluidic devices. Furthermore, the thesis contributes...... community. Although the study of the FVM is carried out using a simple heat conduction problem, the work illuminates and discusses the technicalities of employing the FVM in connection with topology optimization. Finally, parallelized solution methods are investigated using the high performance computing...

  7. Problems in structural inorganic chemistry

    CERN Document Server

    Li, Wai-Kee; Mak, Thomas Chung Wai; Mak, Kendrew Kin Wah

    2013-01-01

    This book consists of over 300 problems (and their solutions) in structural inorganic chemistry at the senior undergraduate and beginning graduate level. The topics covered comprise Atomic and Molecular Electronic States, Atomic Orbitals, Hybrid Orbitals, Molecular Symmetry, Molecular Geometry and Bonding, Crystal Field Theory, Molecular Orbital Theory, Vibrational Spectroscopy, and Crystal Structure. The central theme running through these topics is symmetry, molecular or crystalline. The problems collected in this volume originate in examination papers and take-home assignments that have been part of the teaching of the book's two senior authors' at The Chinese University of Hong Kong over the past four decades. The authors' courses include Chemical Bonding, Elementary Quantum Chemistry, Advanced Inorganic Chemistry, X-Ray Crystallography, etc. The problems have been tested by generations of students taking these courses.

  8. Problems of Collisional Stellar Dynamics

    CERN Document Server

    Heggie, Douglas C

    2011-01-01

    The discovery of dynamical friction was Chandrasekhar's best known contribution to the theory of stellar dynamics, but his work ranged from the few-body problem to the limit of large N (in effect, galaxies). Much of this work was summarised in the text "Principles of Stellar Dynamics" (Chandrasekhar 1942, 1960), which ranges from a precise calculation of the time of relaxation, through a long analysis of galaxy models, to the behaviour of star clusters in tidal fields. The later edition also includes the work on dynamical friction and related issues. In this review we focus on progress in the collisional aspects of these problems, i.e. those where few-body interactions play a dominant role, and so we omit further discussion of galaxy dynamics. But we try to link Chandrasekhar's fundamental discoveries in collisional problems with the progress that has been made in the 50 years since the publication of the enlarged edition.

  9. Psychological Distress and Problem Drinking.

    Science.gov (United States)

    Mentzakis, Emmanouil; Roberts, Bayard; Suhrcke, Marc; McKee, Martin

    2016-03-01

    We examine the influence of harmful alcohol use on mental health using a flexible two-step instrumental variables approach and household survey data from nine countries of the former Soviet Union. Using alcohol advertisements to instrument for alcohol, we show that problem drinking has a large detrimental effect on psychological distress, with problem drinkers exhibiting a 42% increase in the number of mental health problems reported and a 15% higher chance of reporting very poor mental health. Ignoring endogeneity leads to an underestimation of the damaging effect of excessive drinking. Findings suggest that more effective alcohol policies and treatment services in the former Soviet Union may have added benefits in terms of reducing poor mental health. PMID:25640167

  10. Fracture problems in composite materials

    Science.gov (United States)

    Erdogan, F.

    1972-01-01

    A series of fracture problems in composite materials are identified, their methods of solution are briefly discussed, and some sample results are presented. The main problem of interest is the determination of the stress state in the neighborhood of localized imperfections such as cracks and inclusions which may exist in the composite. Particular emphasis is placed on the evaluation of quantities such as the stress intensity factors, the power of the stress singularity, and the strain energy release rate, which may be used directly or indirectly in connection with an appropriate fracture criterion for the prediction of fracture initiation and propagation load levels. The topics discussed include a crack in layered composites, a crack terminating at and going through a bi-material interface, a penny-shaped crack in a filament-reinforced elastic matrix, and inclusion problems in bonded materials.

  11. Squared Metric Facility Location Problem

    CERN Document Server

    Fernandes, Cristina G; Miyazawa, Flávio K; Pedrosa, Lehilton L C

    2011-01-01

    Jain et al. proposed two well-known algorithms for the Metric Facility Location Problem (MFLP), that achieve approximation ratios of 1.861 and 1.61. Mahdian et al. combined the latter algorithm with scaling and greedy augmentation techniques, obtaining a 1.52-approximation for the MFLP. We consider a generalization of the Squared Euclidean Facility Location Problem, when the distance function is a squared metric, which we call Squared Metric Facility Location Problem (SMFLP). We show that the algorithms of Jain et al. and of Mahdian et al., when applied to this variant of the facility location, achieve approximation ratios of 2.87, 2.43, and 2.17, respectively. It is shown that, for the SMFLP, there is no 2.04-approximation algorithm, assuming P $\

  12. On the Wiener disorder problem

    CERN Document Server

    Sezer, Semih Onur

    2010-01-01

    In the Wiener disorder problem, the drift of a Wiener process changes suddenly at some unknown and unobservable disorder time. The objective is to detect this change as quickly as possible after it happens. Earlier work on the Bayesian formulation of this problem brings optimal (or asymptotically optimal) detection rules assuming that the prior distribution of the change time is given at time zero, and additional information is received by observing the Wiener process only. Here, we consider a different information structure where possible causes of this disorder are observed. More precisely, we assume that we also observe an arrival/counting process representing external shocks. The disorder happens because of these shocks, and the change time coincides with one of the arrival times. Such a formulation arises, for example, from detecting a change in financial data caused by major financial events, or detecting damages in structures caused by earthquakes. In this paper, we formulate the problem in a Bayesian ...

  13. Bernoulli Variational Problem and Beyond

    KAUST Repository

    Lorz, Alexander

    2013-12-17

    The question of \\'cutting the tail\\' of the solution of an elliptic equation arises naturally in several contexts and leads to a singular perturbation problem under the form of a strong cut-off. We consider both the PDE with a drift and the symmetric case where a variational problem can be stated. It is known that, in both cases, the same critical scale arises for the size of the singular perturbation. More interesting is that in both cases another critical parameter (of order one) arises that decides when the limiting behaviour is non-degenerate. We study both theoretically and numerically the values of this critical parameter and, in the symmetric case, ask if the variational solution leads to the same value as for the maximal solution of the PDE. Finally we propose a weak formulation of the limiting Bernoulli problem which incorporates both Dirichlet and Neumann boundary condition. © 2013 Springer-Verlag Berlin Heidelberg.

  14. Sensitivity analysis for activation problems

    International Nuclear Information System (INIS)

    A study has been made about how to develop further the techniques for sensitivity analysis used by FISPACT-II. FISPACT-II is a software suite for the analysis of nuclear activation and transmutation problems, developed for all nuclear applications. The software already permits sensitivity analysis to be performed by Monte Carlo sampling, and a faster uncertainty analysis is made possible by a powerful graph-based approach which generates a reduced set of nuclides on pathways leading to significant contributions to radiological quantities. The peculiar aspects of the sensitivity analysis problem for activation are the large number, typically thousands, of rate equation parameters (decay rates and reaction cross-sections) which all have some degree of associated error, and the fact that activity as a function of time varies as a sum of exponentials, so appears discontinuous as rate parameters are varied unless the sampling frequency is impracticably fast. Nevertheless, Monte Carlo sampling is a generic approach and it is therefore conceivable that techniques more targeted to the activation problem might be beneficial. Moreover, recent theoretical developments have highlighted the importance of a two-stage approach to mathematically similar problems, where in the first stage, information is collected about the global behaviour of the problem, such as the identification of the rate parameters which cause the greatest variation in dose or nuclear activity, before a second stage examines a problem with its scope restricted by the information from the first. In the second stage, for example, Quasi-Monte Carlo sampling may be used in a restricted parameter space. The current work concentrates on the first stage and consists of a review of possible techniques with a detailed examination of the most promising pathways reduction approach, examined directly using FISPACT-II. All the evidence obtained demonstrates the strong potential of this approach. (authors)

  15. Revisiting the medical diagnosis problem

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye; Leron, Uri

    2014-01-01

    in the context of probability, with special focus on one case study – the Medical Diagnosis Problem – which figures prominently in the cognitive psychology research literature and in the so-called rationality debate. Our case study involves a combination of theory, design and experiment: Using the...... extensive psychological research as a theoretical base, we design a new “bridging” task, which is on the one hand formally equivalent to the given “difficult” task, but on the other hand is much more accessible to students’ intuitions. Furthermore, this new task would serve as "stepping stone", enabling......, the medical diagnosis problem...

  16. Java problem-based learning

    OpenAIRE

    Goran P, Šimić

    2012-01-01

    The paper describes the self-directed problem-based learning system (PBL) named Java PBL. The expert module is the kernel of Java PBL. It involves a specific domain model, a problem generator and a solution generator. The overall system architecture is represented in the paper. Java PBL can act as the stand-alone system, but it is also designed to provide support to learning management systems (LMSs). This is provided by a modular design of the system. An LMS can offer th...

  17. Interactive problem solving using LOGO

    CERN Document Server

    Boecker, Heinz-Dieter; Fischer, Gerhard

    2014-01-01

    This book is unique in that its stress is not on the mastery of a programming language, but on the importance and value of interactive problem solving. The authors focus on several specific interest worlds: mathematics, computer science, artificial intelligence, linguistics, and games; however, their approach can serve as a model that may be applied easily to other fields as well. Those who are interested in symbolic computing will find that Interactive Problem Solving Using LOGO provides a gentle introduction from which one may move on to other, more advanced computational frameworks or more

  18. Iron deficiency - a global problem

    International Nuclear Information System (INIS)

    Iron deficiency is an important nutritional global problem. This paper contains summery of information gathered from a dietary survey as iron deficiency anaemia is major public health problem in many developing countries including Pakistan. Comparison of anaemia in different age group and sex versus various regions in the world are given. In Pakistan also anaemia is widespread. According to the report of Micro-Nutrient survey of Pakistan 40% of the population are found to have low level of haemoglobin, more than half of pregnant women suffered from marginal or deficient haemoglobin. (A.B.)

  19. Problems in astrophysical radiation hydrodynamics

    International Nuclear Information System (INIS)

    The basic equations of radiation hydrodynamics are discussed in the regime that the radiation is dynamically as well as thermally important. Particular attention is paid to the question of what constitutes an acceptable approximate non-relativistic system of dynamical equations for matter and radiation in this regime. Further discussion is devoted to two classes of application of these ideas. The first class consists of problems dominated by line radiation, which is sensitive to the velocity field through the Doppler effect. The second class is of problems in which the advection of radiation by moving matter dominates radiation diffusion

  20. Inverse Problems in Structural Mechanics

    OpenAIRE

    Li, Jing

    2005-01-01

    This dissertation deals with the solution of three inverse problems in structural mechanics. The first one is load updating for finite element models (FEMs). A least squares fitting is used to identify the load parameters. The basic studies are made for geometrically linear and nonlinear FEMs of beams or frames by using a four-noded curved beam element, which, for a given precision, may significantly solve the ill-posed problem by reducing the overall number of degrees of freedom (DOF) of t...

  1. PROBLEM MATING BEHAVIOR OF STUDENTS

    OpenAIRE

    Igor Vasileviсh Malimonov; Liudmila Gennad’evna Korol; Irina Georgievna Sinkovskaya; Dmitriy Vladimiroviсh Rakhinskiy

    2015-01-01

    In article problems of preparation of student’s youth for creation of a family are consi-dered.Work purpose: studying of features of marriage behavior of student’s youth. Interest in a problem is actual and caused by an instability situation in society, lack of uniform system of values that can lead to disintegration of a family as social institute. Bases of fundamental value of a family and marriage for development and maintenance of stability in society and the state are analysed.Method of ...

  2. Understanding Problem in Contemporary Hermeneutics

    Directory of Open Access Journals (Sweden)

    Varygin D. V.

    2012-01-01

    Full Text Available Some problems of modern hermeneutics are considered in the article. The hermeneutic practice and theory are correlated with insufficient elaboration of the latter. Rational and irrational hermeneutics are established. To understand the meaning of the text it is necessary to overcome the author’s subjectivity and the language imperfection. The author outlines the main features of the hermeneutic logic and its non-classical character. The hermeneutic truth depends on the position of the author and not just on the objective reality. Importance, relevance and development prospects of the understanding problem in philosophy of natural sciences are specified.

  3. Fluid mechanics problems and solutions

    CERN Document Server

    Spurk, Joseph H

    1997-01-01

    his collection of over 200 detailed worked exercises adds to and complements the textbook Fluid Mechanics by the same author, and illustrates the teaching material through examples. In the exercises the fundamental concepts of Fluid Mechanics are applied to obtaining the solution of diverse concrete problems, and in doing this the student's skill in the mathematical modeling of practical problems is developed. In addition, 30 challenging questions without detailed solutions have been included, and while lecturers will find these questions suitable for examinations and tests, the student himself can use them to check his understanding of the subject.

  4. Unsolved problems in number theory

    CERN Document Server

    Guy, Richard K

    1994-01-01

    Unsolved Problems in Number Theory contains discussions of hundreds of open questions, organized into 185 different topics. They represent numerous aspects of number theory and are organized into six categories: prime numbers, divisibility, additive number theory, Diophantine equations, sequences of integers, and miscellaneous. To prevent repetition of earlier efforts or duplication of previously known results, an extensive and up-to-date collection of references follows each problem. In the second edition, not only extensive new material has been added, but corrections and additions have been included throughout the book.

  5. Problems in astrophysical radiation hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Castor, J.I.

    1983-09-14

    The basic equations of radiation hydrodynamics are discussed in the regime that the radiation is dynamically as well as thermally important. Particular attention is paid to the question of what constitutes an acceptable approximate non-relativistic system of dynamical equations for matter and radiation in this regime. Further discussion is devoted to two classes of application of these ideas. The first class consists of problems dominated by line radiation, which is sensitive to the velocity field through the Doppler effect. The second class is of problems in which the advection of radiation by moving matter dominates radiation diffusion.

  6. The U(1)-Kepler Problems

    OpenAIRE

    Meng, Guowu

    2008-01-01

    Let $n\\ge 2$ be a positive integer. To each irreducible representation $\\sigma$ of $\\mr U(1)$, a $\\mr U(1)$-Kepler problem in dimension $(2n-1)$ is constructed and analyzed. This system is super integrable and when $n=2$ it is equivalent to a MICZ-Kepler problem. The dynamical symmetry group of this system is $\\widetilde {\\mr U}(n, n)$, and the Hilbert space of bound states ${\\ms H}(\\sigma)$ is the unitary highest weight representation of $\\widetilde {\\mr U}(n, n)$ with highest weight $$(\\und...

  7. Trapezoidal Fuzzy Numbers for the Transportation Problem

    OpenAIRE

    Chaudhuri, Arindam; De, Kajal; Chatterjee, Dipak; Mitra, Pabitra

    2013-01-01

    Transportation Problem is an important problem which has been widely studied in Operations Research domain. It has been often used to simulate different real life problems. In particular, application of this Problem in NP Hard Problems has a remarkable significance. In this Paper, we present the closed, bounded and non empty feasible region of the transportation problem using fuzzy trapezoidal numbers which ensures the existence of an optimal solution to the balanced transportation problem. T...

  8. Inner shell energies: experimental problems

    International Nuclear Information System (INIS)

    Progress in theoretical estimates of single vacancy atomic term values has challenged available experimental data. This brief survey of the experimental situation indicates both conceptual and technical problems which are currently faced. Although these interpretational difficulties are formidable, the emergence of systematic trends in the comparison of theory and experiment appears to invite a simple explication

  9. Clustering problems for geochemical data

    International Nuclear Information System (INIS)

    The Union Carbide Corporation, Nuclear Division, Uranium Resource Evaluation Project uses a two-stage sampling program to identify potential uranium districts. Cluster analysis techniques are used in locating high density sampling areas as well as in identifying potential uranium districts. Problems are considered involving the analysis of multivariate censored data, laboratory measurement error, and data standardization

  10. Problems in unification and supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, G.; Henyey, F. (eds.)

    1984-01-01

    Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented. (WHK)

  11. "Top School Problems" Are Myths.

    Science.gov (United States)

    Males, Mike

    1992-01-01

    A well-known "study" comparing the top school problems of 1940 (talking and gum chewing) with those of 1987 (drug abuse, pregnancy, and violence) is nonexistent. In 1940, 49 percent of all youth did not finish high school, 37,000 teenagers died from violence or disease, and 335,000 teens gave birth. Educators should discount pastoral memories and…

  12. Eldercare at Home: Skin Problems

    Science.gov (United States)

    ... can ease the symptoms. Doctors often prescribe an anti-viral drug, such as acyclovir (ZoviraxTM), valacyclovir (ValtrexTM), ... dealing with common caregiving problems. © 2016 Health in Aging. All rights reserved. Feedback • Site Map • Privacy Policy • ...

  13. The Particle--Motion Problem.

    Science.gov (United States)

    Demana, Franklin; Waits, Bert K.

    1993-01-01

    Discusses solutions to real-world linear particle-motion problems using graphing calculators to simulate the motion and traditional analytic methods of calculus. Applications include (1) changing circular or curvilinear motion into linear motion and (2) linear particle accelerators in physics. (MDH)

  14. Exponential family and inverse problems

    Czech Academy of Sciences Publication Activity Database

    Gottvald, Aleš

    Dordrecht: Kluwer Academic Publishers, 2003 - (Rudnicki, M.; Wiak, S.), s. - ISBN 1-4020-1506-2 R&D Projects: GA MŠk ME 526 Institutional research plan: CEZ:AV0Z2065902 Keywords : exponential family * inverse problems * Bayes' theorem Subject RIV: BD - Theory of Information

  15. Topological evolution and inverse problems

    Czech Academy of Sciences Publication Activity Database

    Gottvald, Aleš

    Dordrecht: Kluwer Academic Publishers, 2003 - (Rudnicki, M.; Wiak, S.), s. - ISBN 1-4020-1506-2 R&D Projects: GA MŠk ME 526 Institutional research plan: CEZ:AV0Z2065902 Keywords : topological evolution * inverse problems * Cartan's exterior calculus Subject RIV: BD - Theory of Information

  16. Topological evolution and inverse problems

    Czech Academy of Sciences Publication Activity Database

    Gottvald, Aleš

    Lodz: IMET, 2002, s. 12. [OIPE. LODZ (PL), 12.09.2002-14.09.2002] R&D Projects: GA MŠk ME 526 Grant ostatní: AIP(XC) KONTAKT 57/2000 Institutional research plan: CEZ:AV0Z2065902 Keywords : topological evolution * inverse problems Subject RIV: BD - Theory of Information

  17. Exponential family and inverse problems

    Czech Academy of Sciences Publication Activity Database

    Gottvald, Aleš

    Lodz: IMET, 2002, s. 13. [OIPE. LODZ (PL), 12.09.2002-14.09.2002] R&D Projects: GA MŠk ME 526 Grant ostatní: AIP(XC) KONTAKT 57/2000 Institutional research plan: CEZ:AV0Z2065902 Keywords : exponential family * inverse problems Subject RIV: BD - Theory of Information

  18. Beginnings of the Cauchy problem

    OpenAIRE

    Choquet-Bruhat, Yvonne

    2014-01-01

    Brief account of results on the Cauchy problem for the Einstein equations starting with early the works of Darmois and Lichnerowicz and going up to the proofs of the existence and uniqueness of solutions global in space and local in time, in Sobolev spaces, for the general equations either in vacuum or with classical sources.

  19. On the optimal sizing problem

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    1994-01-01

    The paper studies the problem of determining the number and dimensions of sizes of apparel so as to maximize profits. It develops a simple one-variable bisection search algorithm that gives the optimal solution. An example is solved interactively using a Macintosh LC and Math CAD, a mathematical...

  20. Secretary Problems with Convex Costs

    CERN Document Server

    Barman, Siddharth; Chawla, Shuchi; Malec, David

    2011-01-01

    We consider online resource allocation problems where given a set of requests our goal is to select a subset that maximizes a value minus cost type of objective function. Requests are presented online in random order, and each request possesses an adversarial value and an adversarial size. The online algorithm must make an irrevocable accept/reject decision as soon as it sees each request. The "profit" of a set of accepted requests is its total value minus a convex cost function of its total size. This problem falls within the framework of secretary problems. Unlike previous work in that area, one of the main challenges we face is that the objective function can be positive or negative and we must guard against accepting requests that look good early on but cause the solution to have an arbitrarily large cost as more requests are accepted. This requires designing new techniques. We study this problem under various feasibility constraints and present online algorithms with competitive ratios only a constant fa...

  1. Symptoms as the main problem

    DEFF Research Database (Denmark)

    Rosendal, Marianne; Carlsen, Anders Helles; Rask, Mette Troellund

    2016-01-01

    Dette studie undersøger tilfredsheden hos patienter, der blev afsluttet i almen praksis uden specifik diagnose, dvs. hvor lægen efter afsluttet konsultation kun kunne anføre "symptom" eller "problem" som slutdiagnose. Det drejer sig om ca. 1/3 af alle helbredsrelaterede konsultationer i almen...

  2. Problems with textile wastewater discharge

    International Nuclear Information System (INIS)

    The general character of textile industry wastewaters is briefly discussed. General guidelines and practice in Finland when discharging textile industry wastewaters to municipal sewer systems is described. A survey revealed that most municipalities experience some problems due to textile industry wastewaters. Pretreatment is not always practiced and in some cases pretreatment is not operated efficiently. (author)

  3. The bicriterion stochastic knapsack problem

    DEFF Research Database (Denmark)

    Andersen, Kim Allan

    We discuss the bicriterion stochastic knapsack problem. It is described as follows. We have a known capacity of some resource, and a finite set of projects. Each project requires some units of the resource which is not known in advance, but given by a discrete probability distribution with a finite...

  4. Dealing with the Dropout Problem.

    Science.gov (United States)

    Gage, N. L.

    1990-01-01

    Examines one national goal--to make our national high school graduation rate reach 90 percent by 2000--by focusing on the dropout problem. Poverty and cultural differences play a major role in determining who drops out. Exploring multiple-intelligences research and emphasizing educational research and development are sound strategies. Includes 33…

  5. Eigenvalue problems in surface superconductivity

    International Nuclear Information System (INIS)

    The aim of the meeting is to discuss several classes of Schroedinger equations appearing within the Ginzburg-Landau theory of superconductivity. The related problems are discussed from several perspectives including semiclassical analysis, PDE in non-smooth domains, geometric spectral theory and operator theory, which should provide a new insight into various phenomena appearing in superconducting systems.

  6. The P versus NP Problem

    CERN Document Server

    Dube, Rakesh

    2010-01-01

    Removed by arXiv administration. This article was plagiarized directly from Stephen Cook's description of the problem for the Clay Mathematics Institute. See http://gauss.claymath.org:8888/millennium/P_vs_NP/pvsnp.pdf for the original text.

  7. Quantum Annealing of Hard Problems

    OpenAIRE

    Jorg, Thomas; Krzakala, Florent; Kurchan, Jorge; Maggs, A C

    2009-01-01

    Quantum annealing is analogous to simulated annealing with a tunneling mechanism substituting for thermal activation. Its performance has been tested in numerical simulation with mixed conclusions. There is a class of optimization problems for which the efficiency can be studied analytically using techniques based on the statistical mechanics of spin glasses.

  8. Inflation and the Measurement Problem

    CERN Document Server

    Alexander, Stephon; Magueijo, Joao

    2016-01-01

    We discuss the cosmological measurement problem (see [1] for a review), and propose a solution. Our approach is an effective wavefunction collapse mechanism arising from a novel interaction between Fourier modes, to be contrasted with fundamental modifications to the Schrodinger equation [2, 3].

  9. Inconsistent Investment and Consumption Problems

    DEFF Research Database (Denmark)

    Kronborg, Morten Tolver; Steffensen, Mogens

    2015-01-01

    In a traditional Black–Scholes market we develop a verification theorem for a general class of investment and consumption problems where the standard dynamic programming principle does not hold. The theorem is an extension of the standard Hamilton–Jacobi–Bellman equation in the form of a system of...

  10. Problems, Perseverance, and Mathematical Residue.

    Science.gov (United States)

    Thom, Jennifer S.; Pirie, Susan E. B.

    2002-01-01

    Reports on a study in which three 3rd grade students were presented with the volume of cuboids. Examines the problem solving actions students demonstrate and analyzes students' strategies and solutions. Explores the connection between spatial structuring and the use of numerical operation. Considers perseverance and control emerging when solving…

  11. INTERCULTURAL COMMUNICATION: PROBLEMS AND TENDENCIES

    OpenAIRE

    Kryachko, O.

    2014-01-01

    This article deals with the problems of intercultural communication as a developing science, analyses its formation, stages and main approaches. It also presents the possible vectors of its development. World's evolution demands healthy coexistence not only between different countries, but within one country, one ethnic, one group of people. It discusses both social and individual factors which influence the act of communication.

  12. Management problems of staff motivation

    OpenAIRE

    PUZYNYA T.A.

    2015-01-01

    Staff motivation is a major link in improving the competitiveness of any organization. One of the main problems of management of motivation of staff is the individuality of each employee, so the knowledge of psychology and individual needs will help organizations effectively manage staff.

  13. Is the Age Problem Resolved?

    Indian Academy of Sciences (India)

    Ali Akbar Navabi; Nematollah Riazi

    2003-03-01

    The cosmological, astrophysical, and nucleocosmochronological methods for estimating the age of the universe and the corresponding uncertainties are comparatively studied in the present paper.We are led to the conclusion that the newmeasurements of cosmological parameters, and the recent estimates of the age of globular clusters have led to the gradual disappearance of the age problem from the arena of modern cosmology.

  14. Inverse Problems in Data Analysis

    Czech Academy of Sciences Publication Activity Database

    Kůrková, Věra

    2006-01-01

    Roč. 82, č. 4 (2006), s. 41-48. ISSN 0033-2097 R&D Projects: GA AV ČR 1ET100300419 Institutional research plan: CEZ:AV0Z10300504 Keywords : learning from data * inverse problem * regularization * reproducing kernel Hilbert spaces Subject RIV: IN - Informatics, Computer Science

  15. Problem Based Learning in Metaverse

    Science.gov (United States)

    Barry, Dana M.; Kanematsu, Hideyuki; Fukumura, Yoshimi

    2010-01-01

    Problem Based Learning (PBL) is a powerful tool for both science and engineering education in the real world. Therefore, Japanese educators/researchers (with assistance from a US educator) carried out a pilot study to determine the effectiveness of using PBL activities in Metaverse. Their project was carried out by student teams from the US and…

  16. Problem Gambling on College Campuses

    Science.gov (United States)

    McComb, Jennifer L.; Hanson, William E.

    2009-01-01

    The vast majority of college students gamble, with some doing so problematically. This article discusses gambling and problem gambling among college students, framing it as an emerging health issue on college campuses nationwide. Given that 4 out of 5 college students admit to gambling, and that approximately 8% gamble problematically, it is…

  17. Rice breeding problems in Korea

    International Nuclear Information System (INIS)

    This paper deals with general rice production in Korea and the problems encountered. The history of rice growing and breeding in Korea is outlined and a description of recent advances in rice breeding is given, including a discussion of some uses of radiation treatments in the breeding programme during the last few years. (author). 2 figs, 3 tabs

  18. PROBLEMS OF LOOSE MATERIALS STORAGE

    OpenAIRE

    Karanský, Jindřich; Herák, David; GÜRDİL, Gürkan A.K; Yunus PINAR

    2012-01-01

    This article describes basic methods of loose materials storage. There are well known problems induced of mechanical properties of mixtures of loose components while storing. This article is focused on equations describing mechanical behavior of such materials and methods of loose materials mechanical properties testing.

  19. On the U(1) problem

    International Nuclear Information System (INIS)

    The resolution of the U(1) problem requires the quark condensates to have a specific THETA dependence. We show that the required THETA dependence arises naturally upon application of the index theorem during the calculation of the dynamically generated quark mass. (orig.)

  20. Introduction: Unsolved Problems on Noise

    Science.gov (United States)

    Oriols, X.; Ciliberto, S.

    2016-05-01

    This paper is an introduction to the special issue of the 7th Int. Conf. on Unsolved Problems on Noise (UPoN) that took place at Casa Convalescència in Barcelona (Spain) in July 2015. The aim of the UPoN conferences is to provide a forum for researchers working on different fields of noise, fluctuations and variability, where they present their scientific problems which resist solutions. The papers of this Special Issue reflect the interdisciplinary topics (physics, biology, circuits, financial markets, psychology, technology, etc) presented at the UPoN conference. Noise is not only a hindrance to signal detection, but it is indeed a valuable source of information (not present in the signal) that help us to get a deeper understanding on how Nature works. This special issue of the 7th International Conference on Unsolved Problems on Noise (UPoN) is dedicated to Laszlo Kish in the occasion of his 60th birthday. He organized the first edition of these UPoN conferences in Szeged (Hungary) in 1996. Many of us have greatly benefited from his ‘volcanic imagination in tackling new problems from unconventional points of views’.

  1. Problem-Oriented Project Studies

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Lerche; Danielsen, Oluf

    2012-01-01

    Focus is on problem-based learning in a networked learning context with focus on the use of technologies in the communicative processes among the participants. Especially, the role of the teacher in such a context is analysed. The classic, traditional role as an expert deciding the curriculum, pr...

  2. Personal Law and Consumer Problems

    Science.gov (United States)

    Graf, David

    1972-01-01

    There is little doubt at Minnetonka High School that the integrated personal law and consumer problems course is effective. The areas studied promote variety, concentration on vital matters, and student interest in the business department as a source of general education. (Author)

  3. Problems in unification and supergravity

    International Nuclear Information System (INIS)

    Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented

  4. Sexual Harrassment: A Hidden Problem.

    Science.gov (United States)

    Sandler, Bernice R.; And Others

    1981-01-01

    The hidden but serious problem of sexual harassment of students and employees by college faculty is discussed, some statistics are given, and legal and court opinions outlined. Harassment as a violation of Title IX is analyzed, and implications for institutional action to curb it are outlined. (MSE)

  5. Problem children or harassed childhood?

    DEFF Research Database (Denmark)

    Warming, Hanne

    The paper examine the discourses among pedagogues in daycare institutions. The analysis shows that the pedagogies identify structural and economic problems, but never the less it is the chldren (and their parents) that the pedagogues blame, when they experience the situation in the day care insti...

  6. Raw materials problem in NFC

    International Nuclear Information System (INIS)

    The problems of the production and consumption of the native uranium in the nuclear fuel cycle are discussed. The ways of the investigations into the reserves of the starting materials and reprocessing of the products on the basis of zirconium, rare earth concentrates, fluorite (for fluoride production), lithium, niobium and tantalum ore are noted

  7. Group Counselling for Problem Gambling.

    Science.gov (United States)

    Coman, Gregory J.; Evans, Barry J.; Burrows, Graham D.

    2002-01-01

    Group counseling has been used to assist individuals to overcome difficulties associated with problem gambling behavior; however, there are few reports of this application in the clinical and research literature. This paper provides a brief review of group counseling, and describes the application of group counseling to assist individuals with…

  8. The Vessel Schedule Recovery Problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Plum, Christian Edinger Munk; Vaaben, Bo;

    Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker...

  9. Problems with German Science Education.

    Science.gov (United States)

    Riess, Falk

    2000-01-01

    The main problems of science teaching in Germany are students' lack of interest and motivation and their poor understanding of scientific concepts, ideas, methods, and results. Lists examples from science curricula and textbooks and describes some reform projects in Germany. Proposes a compensatory program in order to create prerequisites for…

  10. The Child-Fat Problem.

    Science.gov (United States)

    Eberstadt, Mary

    2003-01-01

    Experts believe that child obesity is a serious medical problem that affects people in all socioeconomic groups. Suggests that there is a relationship between absentee parents, particularly mothers, and obese children, focusing on working/absentee mothers, television watching habits, the prophylactic effect of breastfeeding, and poor exercise…

  11. Childhood Obesity: A Heavy Problem

    Science.gov (United States)

    Costley, Kevin C.; Leggett, Timothy

    2010-01-01

    The youth of today are faced with a big problem; they are becoming more obese every day. The time of children playing outside all day and being extremely active has been overtaken by the television and video games. The days of sitting down as a family and eating a good healthy meal has been replaced by the rush to the nearest fast food…

  12. Eldercare at Home: Hearing Problems

    Science.gov (United States)

    ... members and friends to comment on how much communication has improved when your mother is wearing the hearing aid. If your mother is concerned about the appearance of a hearing aid, tell her that most women can style their hair to cover the hearing aids. Problem " ...

  13. Human Problem Solving in 2008

    OpenAIRE

    Pizlo, Zygmunt

    2009-01-01

    This paper presents a bibliography of more than 200 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo database. Journal papers, book chapters, books and dissertations are included. The topics include human development, education, neuroscience, research in applied settings, as well as animal studies.

  14. Human Problem Solving in 2010

    OpenAIRE

    Pizlo, Zygmunt

    2012-01-01

    This paper presents a bibliography of 100 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo database. Journal papers, book chapters, and dissertations are included. The topics include human development, education, neuroscience, and research in applied settings, as well as animal studies.

  15. Monte Carlo photon benchmark problems

    International Nuclear Information System (INIS)

    Photon benchmark calculations have been performed to validate the MCNP Monte Carlo computer code. These are compared to both the COG Monte Carlo computer code and either experimental or analytic results. The calculated solutions indicate that the Monte Carlo method, and MCNP and COG in particular, can accurately model a wide range of physical problems. 8 refs., 5 figs

  16. The Problem of Private Language

    Directory of Open Access Journals (Sweden)

    M.A Abdollahi

    2014-09-01

    This language is, according to Wittgenstein, impossible because it leads to epistemological and semantic skepticism. The definition of private language contains two elements: the “privacy” and “referring to”. Wittgenstein shows how we may be trapped in solipsism and the only way to avoid this problem is to consider language as a social phenomenon.

  17. Quantum Statistics and Entanglement Problems

    OpenAIRE

    Trainor, L. E. H.; Lumsden, Charles J.

    2002-01-01

    Interpretations of quantum measurement theory have been plagued by two questions, one concerning the role of observer consciousness and the other the entanglement phenomenon arising from the superposition of quantum states. We emphasize here the remarkable role of quantum statistics in describing the entanglement problem correctly and discuss the relationship to issues arising from current discussions of intelligent observers in entangled, decohering quantum worlds.

  18. Rheumatoid arthritis as psychic problem

    OpenAIRE

    Jiří Kaas; Valérie Tóthová; Lukáš Martinek

    2014-01-01

    The article deals with the issue of psychic problems of rheumatoid arthritis patients. Rheumatoid arthritis is a chronic, inflammatory motor system disease with comprehensive impact on the patient's life. The disease is often considered an exclusively physical disease. But such approach is insufficient because the disease is accompanied by motor limitations of different intensities, by pain and by fatigue that cause considerable exhaustio...

  19. Materials on atomic energy problems

    International Nuclear Information System (INIS)

    The author cites and comments legal opinions on problems of atomic energy, i.e. the decision of the Federal Constitutional Court concerning Kalkar and the plutonium economy; Judges of the Federal Constitutional Court on technology and hazards; the 'atomic state'; plutonium at Gorleben; a new safety philosophy after Harrisburg; salt domes unsuitable for atomic waste. (HSCH) 891 HP/HSCH 892 MB

  20. Tube problems: worldwide statistics reviewed

    International Nuclear Information System (INIS)

    EPRI's Steam Generator Strategic Management Project issues an annual report on the progress being made in tackling steam generator problems worldwide, containing a wealth of detailed statistics on the status of operating units and degradation mechanisms encountered. A few highlights are presented from the latest report, issued in October 1993, which covers the period to 31 December 1992. (Author)

  1. Cavitation problems in sodium valves

    International Nuclear Information System (INIS)

    Cavitation poses few problems for sodium valves, in spite of the fact that the loops are not pressurized. This is no doubt due to the low flow velocities in the pipes. For auxiliary loop valves we are attempting to standardize performances with respect to cavitation. For economic reasons cavitation thresholds are approached with large diameter valves. (author)

  2. Bankernes problemer er ikke forbi

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Grosen, Anders; Hansen, Jørn Astrup

    2014-01-01

    Vi har alle tydeligt kunnet se, at bankerne havde store problemer henover finanskrisen. Men mange er efterhånden kommet til den opfattelse, at det nu går mod lysere tider, og at situationen for bankerne langsomt er ved at normalisere sig. Men en velunderbygget artikel i dette nummer af Finans/Invest...

  3. Modified Block Iterative Method for Solving Convex Feasibility Problem, Equilibrium Problems and Variational Inequality Problems

    Institute of Scientific and Technical Information of China (English)

    Shi Sheng ZHANG; Chi Kin CHAN; H.W. JOSEPH LEE

    2012-01-01

    The purpose of this paper is by using the modified block iterative method to propose an algorithm for finding a common element in the intersection of the set of common fixed points of an infinite family of quasi-φ-asymptotically nonexpansive and the set of solutions to an equilibrium problem and the set of solutions to a variational inequality.Under suitable conditions some strong convergence theorems are established in 2-uniformly convex and uniformly smooth Banach spaces.As applications we utilize the results presented in the paper to solving the convex feasibility problem (CFP) and zero point problem of maximal monotone mappings in Banach spaces.The results presented in the paper improve and extend the corresponding results announced by many authors.

  4. Formal language constrained path problems

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvable efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.

  5. Governance of wicked climate adaptation problems

    NARCIS (Netherlands)

    Termeer, C.J.A.M.; Dewulf, A.; Breeman, G.E.

    2013-01-01

    Climate change adaptation has been called a “wicked problem par excellence.” Wicked problems are hard to define because ‘the formulation of the problem is the problem; they are considered a symptom of another problem; they are highly resistant to solutions and extremely interconnected with other pro

  6. THE EFFECTIVENESS OF PROBLEM-BASED LEARNING

    OpenAIRE

    SAGITOVA ZH; MIRZAMBETOVA ZH.; KUNGOZHANOVA A.

    2015-01-01

    This article observes problem-based learning where students engage complex, challenging problems and collaboratively work toward their resolution. Problem-based learning is about students connecting disciplinary knowledge to real-world problems - the motivation to solve a problem becomes the motivation to learn.

  7. Resources in Technology: Problem-Solving.

    Science.gov (United States)

    Technology Teacher, 1986

    1986-01-01

    This instructional module examines a key function of science and technology: problem solving. It studies the meaning of problem solving, looks at techniques for problem solving, examines case studies that exemplify the problem-solving approach, presents problems for the reader to solve, and provides a student self-quiz. (Author/CT)

  8. Problem-elephant translocation: Translocating the problem and the elephant?

    OpenAIRE

    Fernando, Prithiviraj; Leimgruber, Peter; Prasad, Tharaka; Pastorini, Jennifer

    2012-01-01

    Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they we...

  9. Problem-Elephant Translocation: Translocating the Problem and the Elephant?

    OpenAIRE

    Fernando, Prithiviraj; Leimgruber, Peter; Prasad, Tharaka; Pastorini, Jennifer

    2012-01-01

    Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating “problem-elephants” is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they we...

  10. Community Providers’ Views of Alcohol Problems and Drug Problems

    OpenAIRE

    Gassman, Ruth A.; Weisner, Constance

    2005-01-01

    This study contrasts community health and social service providers’ views on alcohol vs. other drug abuse. A probability sample of 457 social work and other providers from a county’s public and private medical and mental health clinics, welfare and criminal justice systems, and substance abuse programs, as well as clergy, private therapists, and physicians were interviewed. For both alcohol and drug problems, providers thought only of severe dysfunctions, which suggest that less severe forms ...

  11. Quadratic programming problems in muscle wrapping and muscle recruitment problems

    Czech Academy of Sciences Publication Activity Database

    Vondrák, Vít

    Ostrava: VŠB –TU Ostrava, 2006 - (Sameš, M.), s. 51-52 ISBN 80-248-1151-0. [Seminář aplikované matematiky Ostravice 2006. Ostravice, Hotel Sepetná (CZ), 13.09.2006-15.09.2006] Institutional research plan: CEZ:AV0Z20760514 Keywords : biomechanical simulation * mathematical programming * contact problem Subject RIV: BA - General Mathematics

  12. Radon: A health problem and a communication problem

    International Nuclear Information System (INIS)

    The US Environmental Protection Agency (USEPA) is making great efforts to alert the American public to the potential health risks of radon in homes. The news media have widely publicized radon as a problem; state and local governments are responding to public alarms; and hundreds of radon open-quotes expertsclose quotes are now offering radon detection and mitigation services. Apparently, USEPA's communication program is working, and the public is becoming increasingly concerned with radon. But are they concerned with radon as a open-quotes healthclose quotes problem in the way USEPA intended? The answer is yes, partly. More and more, however, the concerns are about home resale values. Many homebuyers are now deciding whether to buy on the basis of a single radon screening measurement, comparing it with USEPA's action guide of 4 pCi L-1. They often conclude that 3.9 is OK, but 4.1 is not. Here is where the communication problems begin. The public largely misunderstands the significance of USEPA's guidelines and the meaning of screening measurements. Seldom does anyone inquire about the quality of the measurements, or the results of USEPA performance testing? Who asks about the uncertainty of lifetime exposure assessments based on a 1-hour, 1-day, 3-day, or even 30-day measurement? Who asks about the uncertainty of USEPA's risk estimates? Fortunately, an increasing number of radiation protection professions are asking such questions. They find that USEPA's risk projections are based on many assumptions which warrant further evaluation, particularly with regard to the combined risks of radon and cigarette-smoking. This is the next communication problem. What are these radiation professions doing to understand the bases for radon health-risk projections? Who is willing to communicate a balanced perspective to the public? Who is willing to communicate the uncertainty and conservatism in radon measurements and risk estimates?

  13. Language structures of pupils within problem posing and problem solving

    Czech Academy of Sciences Publication Activity Database

    Roubíček, Filip

    Rzeszów: WUR, 2008 - (Maj, B.; Pytlak, M.; Swoboda, E.), s. 243 ISBN 978-83-7338-420-0. [Childrens´Mathematical Education (CME). Iwonicz Zdrój (PL), 17.08.2008-22.08.2008] R&D Projects: GA AV ČR KJB700190701 Institutional research plan: CEZ:AV0Z10190503 Keywords : mathematics education * language * problem posing Subject RIV: AM - Education

  14. Non-normal Hasemann Boundary Value Problem

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We will discuss the non-normal Hasemann boundary value problem:we may find these results are coincided with those of normal Hasemann boundary value problem and non normal Riemann boundary value problem.

  15. Children's Health Problems and Maternal Work Status.

    Science.gov (United States)

    Salkever, David S.

    1982-01-01

    This paper estimates the influence on working mothers' employment status of children's health problems. Effects are estimated for several different types of families, various groups of health problems, and differing degrees of problem severity. (CT)

  16. A Flow Approach to Bankruptcy Problems

    OpenAIRE

    Branzei, Rodica; Ferrari, Giulio; Fragnelli, Vito; Tijs, Stef

    2008-01-01

    In this note we represent a classical bankruptcy problem as a standard flow problem on a simple network and implement some known division rules from the bankruptcy literature via suitable cost functions in the related minimum cost flow problem.

  17. An archetype hydrogen atmosphere problem

    International Nuclear Information System (INIS)

    Populations for the first three bound states and the continuum of hydrogen are determined for an isothermal, hydrostatic atmosphere at 20000K. The atmosphere is treated as being optically thin in the Balmer and Paschen continua and illuminated by continuum radiation at these wavelengths with prescribed radiation temperatures. The atmosphere is optically thick in the 2-1,3-1,3-2 and c-1 transitions. Three stages of approximation are treated: (1) radiative detailed balance in the 2-1, 3-1 and 3-2 transitions, (2) radiative detailed balance in the 3-1 and 3-2 transitions, and (3) all transitions out of detailed balance. The solution of this problem is non-trivial, and presents sufficient difficulty to have caused failure of at least one rather standard technique. The problem is thus a good archetype against which new methods, or new implementations of old methods may be tested. (Auth.)

  18. COUNTERFEIT DRUGS: PROBLEMS AND SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Khanna Surabhi

    2010-12-01

    Full Text Available The pharmaceutical industry is under extraordinary strain. Facing the wrath of consumers because of the cost of products, constantly answering the questions of state and federal legislators looking to control health care costs, and losing value in the marketplace, the industry’s hands are more than full. A less discussed but substantial problem impacts all of pharmaceutical industry’s other problems, counterfeiting. The World Health Organization estimates that counterfeit drugs make up about 10 percent of the global medicine market, and more than 25 percent in developing countries. With counterfeit drugs increasingly finding their way into global distribution chains and ultimately into patients' mouths, it is essential that pharmaceutical companies have effective enforcement strategies to combat the manufacture and distribution of counterfeit drugs.

  19. An archetype hydrogen atmosphere problem

    Science.gov (United States)

    Athay, R. G.; Mihalas, D.; Shine, R. A.

    1975-01-01

    Populations for the first three bound states and the continuum of hydrogen are determined for an isothermal hydrostatic atmosphere at 20,000 K. The atmosphere is treated as optically thin in the Balmer and Paschen continua and illuminated by continuum radiation at these wavelengths with prescribed radiation temperatures. The atmosphere is optically thick in the 2-1, 3-1, 3-2 and c-1 transitions. Three stages of approximation are treated: (1) radiative detailed balance in the 2-1, 3-1 and 3-2 transitions, (2) radiative detailed balance in the 3-1 and 3-2 transitions, and (3) all transitions out of detailed balance. The solution of this problem is nontrivial and presents sufficient difficulty to have caused the failure of at least one rather standard technique. The problem is thus a good archetype against which new methods or new implementations of old methods may be tested.

  20. Stochastic problems in population genetics

    CERN Document Server

    Maruyama, Takeo

    1977-01-01

    These are" notes based on courses in Theoretical Population Genetics given at the University of Texas at Houston during the winter quarter, 1974, and at the University of Wisconsin during the fall semester, 1976. These notes explore problems of population genetics and evolution involving stochastic processes. Biological models and various mathematical techniques are discussed. Special emphasis is given to the diffusion method and an attempt is made to emphasize the underlying unity of various problems based on the Kolmogorov backward equation. A particular effort was made to make the subject accessible to biology students who are not familiar with stochastic processes. The references are not exhaustive but were chosen to provide a starting point for the reader interested in pursuing the subject further. Acknowledgement I would like to use this opportunity to express my thanks to Drs. J. F. Crow, M. Nei and W. J. Schull for their hospitality during my stays at their universities. I am indebted to Dr. M. Kimura...

  1. Problems in practical radiation education

    International Nuclear Information System (INIS)

    Based on the results of questionnaire survey carried out in 1995 and 1997 and addressed to the same students in a senior high school, Japan, the author arrived at a conclusion that the students had the chance to get information on radiation from the mass media other than at school during two school year. At school they learn through a textbook and also complementary educational materials the teachers provide which will help understanding and improving the interests in radiations. In the practice, some important problems remain unsolved: the student's feeling toward radiations as risky, inadequate descriptions on radiations found in the textbook, and the difficulties in obtaining teaching materials for experiments. These problems must be resolved first of all for the solution of our future energy supply. (S. Ohno)

  2. Allocation Problems and Market Design

    DEFF Research Database (Denmark)

    Smilgins, Aleksandrs

    The thesis contains six independent papers with a common theme: Allocation problems and market design. The first paper is concerned with fair allocation of risk capital where independent autonomous subunits have risky activities and together constitute the entity's total risk, whose associated risk...... capital has to be shared among the subunits. The problem is modeled as a TU game based on suitable measures of risk, which are applied to estimate the associated value of any possible coalition. The paper suggests the use of Lorenz undominated core selections for allocation of risk capital. It is argued...... that such a solution satisfies a number of desirable properties violated by the conventional alternatives. The second paper is concerned with computational aspects of determining the set of Lorenz undominated core selections. The paper develops an algorithm. The third paper uses the cooperative game...

  3. Renormalisation as an inference problem

    CERN Document Server

    Bény, Cédric

    2013-01-01

    In physics we attempt to infer the rules governing a system given only the results of imprecise measurements. This is an ill-posed problem because certain features of the system's state cannot be resolved by the measurements. However, by ignoring the irrelevant features, an effective theory can be made for the remaining observable relevant features. We explain how these relevant and irrelevant degrees of freedom can be concretely characterised using quantum distinguishability metrics, thus solving the ill-posed inference problem. This framework then allows us to provide an information-theoretic formulation of the renormalisation group, applicable to both statistical physics and quantum field theory. Using this formulation we argue that, given a natural model for an experimentalist's spatial and field-strength measurement uncertainties, the set of Gaussian states emerges as the relevant manifold of effective states and the n-point correlation functions correspond to the relevant observables. Our methods also p...

  4. Networks in social policy problems

    CERN Document Server

    Scotti, marco

    2012-01-01

    Network science is the key to managing social communities, designing the structure of efficient organizations and planning for sustainable development. This book applies network science to contemporary social policy problems. In the first part, tools of diffusion and team design are deployed to challenges in adoption of ideas and the management of creativity. Ideas, unlike information, are generated and adopted in networks of personal ties. Chapters in the second part tackle problems of power and malfeasance in political and business organizations, where mechanisms in accessing and controlling informal networks often outweigh formal processes. The third part uses ideas from biology and physics to understand global economic and financial crises, ecological depletion and challenges to energy security. Ideal for researchers and policy makers involved in social network analysis, business strategy and economic policy, it deals with issues ranging from what makes public advisories effective to how networks influenc...

  5. A one dimensional Hammerstein problem

    Directory of Open Access Journals (Sweden)

    Jun Hua

    1999-12-01

    Full Text Available Nonlinear equations of the form $L[u]=lambda g(u$ where $L$ is a linear operator on a function space and $g$ maps $u$ to the composition function $gcirc u$ arise in the theory of spontaneous combustion. If $L$ is invertible, such an equation can be written as a Hammerstein equation, $u=B[u]$ where $B[u]=lambda L^{-1}[g(u]$. To investigate the importance of the growth rate of $g$ and the sign and magnitude of $lambda $ on the number of solutions of such problems, in this paper we consider the one-dimensional problem $L(x=lambda g(x$ where $L(x=ax$.

  6. Cinema, Fermi Problems, & General Education

    CERN Document Server

    Efthimiou, C J

    2006-01-01

    During the past several years the authors have developed a new approach to the teaching of Physical Science, a general education course typically found in the curricula of nearly every college and university. This approach, called `Physics in Films', uses scenes from popular movies to illustrate physical principles and has excited student interest and improved student performance. The analyses of many of the scenes in `Physics in Films' are a direct application of Fermi calculations -- estimates and approximations designed to make solutions of complex and seemingly intractable problems understandable to the student non-specialist. The intent of this paper is to provide instructors with examples they can use to develop skill in recognizing Fermi problems and making Fermi calculations in their own courses.

  7. Modern problems in insurance mathematics

    CERN Document Server

    Martin-Löf, Anders

    2014-01-01

    This book is a compilation of 21 papers presented at the International Cramér Symposium on Insurance Mathematics (ICSIM) held at Stockholm University in June, 2013. The book comprises selected contributions from several large research communities in modern insurance mathematics and its applications. The main topics represented in the book are modern risk theory and its applications, stochastic modelling of insurance business, new mathematical problems in life and non-life insurance, and related topics in applied and financial mathematics. The book is an original and useful source of inspiration and essential reference for a broad spectrum of theoretical and applied researchers, research students and experts from the insurance business. In this way, Modern Problems in Insurance Mathematics will contribute to the development of research and academy–industry co-operation in the area of insurance mathematics and its applications.

  8. Retrofitting and the mu Problem

    Energy Technology Data Exchange (ETDEWEB)

    Green, Daniel; Weigand, Timo; /SLAC /Stanford U., Phys. Dept.

    2010-08-26

    One of the challenges of supersymmetry (SUSY) breaking and mediation is generating a {mu} term consistent with the requirements of electro-weak symmetry breaking. The most common approach to the problem is to generate the {mu} term through a SUSY breaking F-term. Often these models produce unacceptably large B{mu} terms as a result. We will present an alternate approach, where the {mu} term is generated directly by non-perturtative effects. The same non-perturbative effect will also retrofit the model of SUSY breaking in such a way that {mu} is at the same scale as masses of the Standard Model superpartners. Because the {mu} term is not directly generated by SUSY breaking effects, there is no associated B{mu} problem. These results are demonstrated in a toy model where a stringy instanton generates {mu}.

  9. Complex analogues of real problems

    DEFF Research Database (Denmark)

    Esdahl-Schou, Rune

    . Using geometrical interpretations we construct sets with properties similar to the sets considered in the real case. We then formulate a conjecture which can be interpreted as a complex version of Schmidt's original conjecture. Finally we construct a variant of Schmidt's game, to show a partial result......This thesis will be a mix of different problems in number theory. As such it is split into two natural parts. The rst part focuses on normal numbers and construction of numbers that are normal to a given complex base. It is written in the style of a thorough and introductory paper on that subject......, Pollington and Velani, and inspired by this An gave a different proof which provides a stronger result. The conjecture is concerned with intersections of certain sets in the plane and are as such a real problem. We will consider a slightly different setup where the real plane is replaced by the complex plane...

  10. On the tumbling toast problem

    Science.gov (United States)

    Borghi, Riccardo

    2012-09-01

    A didactical revisitation of the so-called tumbling toast problem is presented here. The numerical solution of the related Newton's equations has been found in the space domain, without resorting to the complete time-based law of motion, with a considerable reduction of the mathematical complexity of the problem. This could allow the effect of the different physical mechanisms ruling the overall dynamics to be appreciated in a more transparent way, even by undergraduates. Moreover, the availability from the literature of experimental investigations carried out on tumbling toast allows us to propose different theoretical models of growing complexity in order to show the corresponding improvement of the agreement between theory and observation.

  11. Numerical models for differential problems

    CERN Document Server

    Quarteroni, Alfio

    2014-01-01

    In this text, we introduce the basic concepts for the numerical modelling of partial differential equations. We consider the classical elliptic, parabolic and hyperbolic linear equations, but also the diffusion, transport, and Navier-Stokes equations, as well as equations representing conservation laws, saddle-point problems and optimal control problems. Furthermore, we provide numerous physical examples which underline such equations. We then analyze numerical solution methods based on finite elements, finite differences, finite volumes, spectral methods and domain decomposition methods, and reduced basis methods. In particular, we discuss the algorithmic and computer implementation aspects and provide a number of easy-to-use programs. The text does not require any previous advanced mathematical knowledge of partial differential equations: the absolutely essential concepts are reported in a preliminary chapter. It is therefore suitable for students of bachelor and master courses in scientific disciplines, an...

  12. Problem Formulation in Planning and Design

    OpenAIRE

    Volkema, Roger J.

    1983-01-01

    This paper deals with the role of problem formulation in planning and design, including: (a) the importance of problem formulation to planning and design; (b) problematic, physiological, psychological and environmental factors that can affect the formulation process; and (c) problem formulation heuristics. Two types of formulation heuristics are identified---problem reduction and problem expansion. Because the latter type has received little empirical research, an initial study of a problem e...

  13. The Paulsen Problem in Operator Theory

    OpenAIRE

    Casazza, Peter G.; Cahill, Jameson

    2011-01-01

    The Paulsen Problem in Hilbert space frame theory has proved to be one of the most intractable problems in the field. We will help explain why by showing that this problem is equivalent to a fundamental, deep problem in operator theory. Along the way we will give a new exact computation for chordal distances, we will give a generalization of these problems and we will spell out exactly the complementary versions of the problem.

  14. A bicriterion Steiner tree problem on graph

    Directory of Open Access Journals (Sweden)

    Vujošević Mirko B.

    2003-01-01

    Full Text Available This paper presents a formulation of bicriterion Steiner tree problem which is stated as a task of finding a Steiner tree with maximal capacity and minimal length. It is considered as a lexicographic multicriteria problem. This means that the bottleneck Steiner tree problem is solved first. After that, the next optimization problem is stated as a classical minimums Steiner tree problem under the constraint on capacity of the tree. The paper also presents some computational experiments with the multicriteria problem.

  15. Health problems of domestic pigeons

    OpenAIRE

    Pilėnaitė, Ginvilė

    2007-01-01

    In this scientific work the most important problems and advice under the maintenance of pigeons are described. The chapter 1 – introduction. In it it is described the past and the future pigeon breeding in the world and in Lithuania. In 2 chapter biological features of house pigeons are described. In 3 chapter cultivation and duplication of house pigeons is described. In chapter 4 it is described about care of house pigeons, preparation of their nursery and the technical equipment. There desi...

  16. GRAY MARKETING: PROBLEMS, PROSPECTS & STRATEGIES

    OpenAIRE

    PREETI KHATRI

    2013-01-01

    Understanding the grey marketing…….Gray markets occur when a product is designed and destined for a particular market, and an intermediary known as a 'gray marketer' brings that product to a second market to sell it for less than its list price in that second market. (David Soberman, 2012)The grey market has been escalating rapidly, leading to a number of problems including loss of revenue and margin, damage to the carrier affiliation, depreciation of the brand, possible liability and safety ...

  17. Communication Problems in Crisis Response

    OpenAIRE

    Lundberg, Jonas; Asplund, Mikael

    2011-01-01

    This paper describes five problem areas of communication that occur during crisis response. These areas arecommunication infrastructure, situation awareness, individual and organizational common ground, form andcontent of messages, and communication paths through organizations. Five focus groups with Swedish fieldpersonnel from national and international crises were performed. The main contribution of this article is ahypothesis, based on the outcomes of the focus groups, about the relation b...

  18. Problem Solving in Latino Families

    OpenAIRE

    Torres, Eliza

    2012-01-01

    This study examined parent engagement, child engagement, and quality of problem solving in a sample of families engaged in a trial of parent management training intervention. Data were collected for treatment and control groups at preintervention and 2, 4, and 6 months after the initial assessment. Variables in this study were measured utilizing a global coding scheme used to categorize parent-child behavioral observations. The coding scheme was developed by Forgatch, Knutson, and Mayne. Prel...

  19. Aptamers: Problems, Solutions and Prospects

    OpenAIRE

    Lakhin, A.; Tarantul, V.; Gening, L.

    2013-01-01

    Aptamers are short single-stranded oligonucleotides that are capable of binding various molecules with high affinity and specificity. When the technology of aptamer selection was developed almost a quarter of a century ago, a suggestion was immediately put forward that it might be a revolutionary start into solving many problems associated with diagnostics and the therapy of diseases. However, multiple attempts to use aptamers in practice, although sometimes successful, have been generally mu...

  20. Corrosion problems of power engineering

    International Nuclear Information System (INIS)

    The proceedings contain 26 contributions, out of which 11 have been inputted in INIS. These are concerned with methods for the evaluation of corrosion resistance of materials for the nuclear industry, with examination of the corrosion behavior of composite overlays and of steels after the action of decontamination solutions, and with theoretical models of crack propagation. Corrosion problems of steam turbines, steam generator tubes and thermocouple bushings are discussed. (M.D.). 28 figs., 8 tabs., 63 refs

  1. Branching problems of unitary representations

    OpenAIRE

    Kobayashi, Toshiyuki

    2003-01-01

    The irreducible decomposition of a unitary representation often contains continuous spectrum when restricted to a non-compact subgroup. The author singles out a nice class of branching problems where each irreducible summand occurs discretely with finite multiplicity (admissible restrictions). Basic theory and new perspectives of admissible restrictions are presented from both analytic and algebraic view points. We also discuss some applications of admissible restrictions to modular varieties...

  2. Editorial: Defining Interesting Research Problems

    OpenAIRE

    Steven M. Shugan

    2003-01-01

    We argue that research problems are only interesting relative to some external audience. Interesting academic research should impact, at least, that external audience. Hence, we should target our research toward specific external audiences. Several foreboding trends that exacerbate the urgency of this targeting are discussed. To facilitate the targeting task, a partial list of fifteen possible audiences for academic research in marketing is identified. We discuss some of them, including pract...

  3. Problem of professional personality formation

    Directory of Open Access Journals (Sweden)

    Pryazhnikova E.Yu.

    2012-09-01

    Full Text Available The article presents the current approaches to the problem of professional personality formation. It ana-lyzes the impact of professional identity of students on the choice of the specialist field they make. The article highlights certain aspects of the educational environment which promote to formation of compe-tences in students, relating to their choice of professional occupations. The article presents the analysis of students’ internal and external strivings after graduation from the university and their fulfillment.

  4. Health problems in Turner syndrome

    OpenAIRE

    Mehdi Salek; Ahmad Reza Okhovvat; Masoumeh Sadeghi; Hamid Reza Roohafza; Roya Kelishadi; Pooneh Memar Ardestani; Masoumeh Raoufei; Mohammad Hossein Moaddab; Hossein Nejadnik

    2007-01-01

    BACKGROUND: Although cardiovascular malformations are well-recognized congenital anomalies in Turner syndrome (TS), other clinical features and a great variety of dysmorphic signs can also be observed. There are few studies about different medical problems in pre-selected groups of patients with Turner syndrome

  5. Otologic Problems in Turner Syndrome

    OpenAIRE

    Ahmadreza Okhovat; Dr. Mahin Hashemipour; Dr. Alireza Majlesi; Mehdi Salek; Masoumeh Raufi; Dr. Saied Hanif Okhovat

    2011-01-01

    Background and Aim: Turner syndrome is the most common sex chromosome abnormality in females, affecting an estimated 3% of all conceiving females. Otologic disease is a common problem in Turner syndrome patients that is due to a combination of small dysfunction Eustachian tube, palatal dysfunction and cochlear malformation.Methods: This study assessed the otologic and audiologic characteristics of a group of Turner syndrome patients. We studied 40 Turner patients aged 10 to 20 years (mean age...

  6. Quantum gravity: the Inverse problem

    OpenAIRE

    Bel, Ll.

    2016-01-01

    Quantizing the gravitational field described by General relativity being a notorious difficult, unsolved and maybe meaningless problem I use in this essay a different strategy: I consider a linear theory in the framework of Special relativity where the potentials are the components of four linear forms. General relativity and other similar covariant non linear theories can be formulated in this way. The theory that I propose is Lorentz invariant, linear, simple, and can be quantized following...

  7. Statistical (3x+1) -- problem

    OpenAIRE

    Sinai, Yakov

    2002-01-01

    Take an odd number x >0. Then 3x+1 is even and one can find an integer k> 0 so that y= 3x+1/2^k is again odd. We get in this way the mapping T, Tx=y. The paper contains two theorems describing statistical properties of T. The first describes statistical properties of trajectories for large x. The second gives some information about the probability distribution appearing in this problem.

  8. Sleep problems in Rett syndrome

    OpenAIRE

    YOUNG, Deidra; Nagarajan, Lakshmi; de Klerk, Nick; Jacoby, Peter; Ellaway, Carolyn; Leonard, Helen

    2007-01-01

    Rett syndrome (RTT) is a severe neurological disorder, affecting mainly females. It is generally caused by mutations in the MECP2 gene. Sleep problems are thought to occur commonly in Rett syndrome, but there has been little research on prevalence or natural history. An Australian population-based registry of cases born since 1976 has been operating since 1993, with current ascertainment at 300. The Australian Rett Syndrome Database (ARSD) consists of information about Rett syndrome cases inc...

  9. PROBLEMS OF AN EPIC HISTORICISM

    OpenAIRE

    Sozashvili, N.

    2012-01-01

    Explanation of mutual relations between separate genres and intragenre versions special interest is got with problems of an epic historicism to which in the newest scientific literature hardly paid the attention. The typology of an epic historicism is simultaneously typology of epic genres, typology of development of epic creativity. The historicism cannot be isolated from art system; it makes one of its organic qualities. The knowledge of topology and the general laws of epic creativity open...

  10. Tackling the European Migration Problems

    OpenAIRE

    Zimmermann, Klaus F.

    1995-01-01

    A fortress Europe immigration policy is currently observed throughout the European Union. The European migration problem seems to be that, in the face of high and persistent unemployment rates, additional immigration implies further unemployment. This might not be true if immigration helps to erode institutional constraints and enhances labor market flexibility, a point that is seen of particular virtue in the European setting. The paper also argues that past European migration, although limi...

  11. Problems in Navy reimbursable accounting

    OpenAIRE

    Kernen, Bernadette A.

    1990-01-01

    Approved for public release, distribution is unlimited The purpose of this thesis is to identify problems in Navy reimbursable accounting and to develop a comprehensive, entry level financial management guide to assist financial managers at the field level in improving their accountability and control over reimbursable funds. This thesis discusses specific procedures for the effective administration and management of Intra- and Interservice Support Agreements, Economy Act Orders, and Proje...

  12. Women and Substance Abuse Problems

    OpenAIRE

    Poole Nancy; Dell, Colleen Anne; Cormier Renée A

    2004-01-01

    Abstract Health Issues Differences exist in the prevalence and physical health impacts of problem substance use among men and women. These differences are also found in the mental health and trauma events related to substance use, barriers to treatment and harm-reduction services and the impact of substance use on pregnancy and parenting. Data from the 2000–2001 Canadian Community Health Survey and Canada's Alcohol and Other Drugs Survey (1994) were used to explore this issue further. Key Fin...

  13. Structural problems in the crisis

    Directory of Open Access Journals (Sweden)

    J. STEINDL

    2013-12-01

    Full Text Available All over the world the steel industry, the shipyards, the motor car and plastics industries and so on are in difficulty. What may be new, however, is that the structural problem appears now not only in its industrial and regional aspects, but also in its aspect of organisation - the crisis of the large concerns. This paper deals with these various aspects in turn, although they are so closely connected as to be inseparable.  

  14. Structural problems in the crisis

    OpenAIRE

    J. STEINDL

    2013-01-01

    All over the world the steel industry, the shipyards, the motor car and plastics industries and so on are in difficulty. What may be new, however, is that the structural problem appears now not only in its industrial and regional aspects, but also in its aspect of organisation - the crisis of the large concerns. This paper deals with these various aspects in turn, although they are so closely connected as to be inseparable.  

  15. Stability problems in hyperinflation models

    OpenAIRE

    Zink, Helmut

    1993-01-01

    Traditional monetary models of hyperinflation suffer from severe stability problems: equilibria with realistic comparative-static properties are unstable while those with unrealistic comparative statics are stable. In the present paper I develop a model of hyperinflation which is based on an analysis of firms' payment behavior and which uses a weaker concept of stability. The stability properties of this model are consistent with the empirical evidence.

  16. Problems of anthropogenic tritium limitation

    Directory of Open Access Journals (Sweden)

    Kochetkov О.A.

    2013-12-01

    Full Text Available This article contains the current situation in respect to the environmental concentrations of anthropogenic and natural tritium. There are presented and analyzed domestic standards for НТО of all Radiation Safety Standards (NRB, as well as the regulations analyzed for tritium in drinking water taken in other countries today. This article deals with the experience of limitation of tritium and focuses on the main problem of rationing of tritium — rationing of organically bound tritium.

  17. Probability and statistics: selected problems

    OpenAIRE

    Machado, J.A. Tenreiro; Pinto, Carla M. A.

    2014-01-01

    Probability and Statistics—Selected Problems is a unique book for senior undergraduate and graduate students to fast review basic materials in Probability and Statistics. Descriptive statistics are presented first, and probability is reviewed secondly. Discrete and continuous distributions are presented. Sample and estimation with hypothesis testing are presented in the last two chapters. The solutions for proposed excises are listed for readers to references.

  18. Open problems in throughput scheduling

    Czech Academy of Sciences Publication Activity Database

    Sgall, Jiří

    Berlin : Springer, 2012 - (Epstein, L.; Ferragina, P.), s. 2-11 ISBN 978-3-642-33089-6. - (Lecture Notes in Computer Science. 7501). [20th Annual European Symposium on Algorithms (ESA 2012). Ljubljana (SI), 10.09.2012-12.09.2012] R&D Projects: GA AV ČR IAA100190902 Keywords : problem complexity * scheduling Subject RIV: BA - General Mathematics http://link.springer.com/chapter/10.1007%2F978-3-642-33090-2_2

  19. PROBLEMS OF PROJECTS PORTFOLIO MANAGEMENT

    OpenAIRE

    Ванюшкин, Александр Сергеевич

    2013-01-01

    Notwithstanding the existence of the Standard for portfolio management, published by PMI, publications of gurus of project and portfolio management, there are still remaining the series of serious problems in this sphere. In the purposes of operational projects portfolio management we propose to combine method of calendar – grid planning with method of scenarios analysis. Also it is grounded, that the emphasis in monitoring a portfolio must be shifted towards fixing and interpreting changes i...

  20. The fundamental problem of accounting

    OpenAIRE

    Robert D. Cairns

    2013-01-01

    The fundamental problem of economic accounting is to determine a forwardlooking schedule of rentals, user costs or quasirents to provide for the recovery of irreversible investments. The method derived herein relaxes some restrictive assumptions that are common in capital theory. There can be multiple forms of comprehensive capital. Accounting for all forms of capital, including tangible and intangible capital, is symmetrical. The analytical focus becomes one of fixities and frictions and not...

  1. Dynamical problem of micropolar viscoelasticity

    Indian Academy of Sciences (India)

    Rajneesh Kumar; Suman Choudhary

    2001-09-01

    The dynamic problem in micropolar viscoelastic medium has been investigated by employing eigen value approach after applying Laplace and Fourier transformations. An example of infinite space with concentrated force at the origin has been presented to illustrate the application of the approach. The integral transforms have been inverted by using a numerical technique to obtain the displacement components, force stresses, couple stress and microrotation in the physical domain. The results for these quantities are given and illustrated graphically.

  2. Substantiating problems of quantum mechanics

    International Nuclear Information System (INIS)

    Some basic problems, related to the spaces and the operators necessary to describe quantum-mechanical phenomena, are entered upon from a new axiomatic standpoint. Some generalizations are operated, required by convergence criteria, concerning the Fourier transform, the Fourier product and the equation of eigen-values. Physical arguments are brought to support such generalizations and an analysis in view of organizing the structure of the proposed spaces is undertaken. (author)

  3. The physical symbol grounding problem

    OpenAIRE

    VOGT, Paul

    2002-01-01

    This paper presents an approach to solve the symbol grounding problem within the framework of embodied cognitive science. It will be argued that symbolic structures can be used within the paradigm of embodied cognitive science by adopting an alternative definition of a symbol. In this alternative definition, the symbol may be viewed as a structural coupling between an agent's sensorimotor activations and its environment. A robotic experiment is presented in which mobile robots develop a symbo...

  4. Human Problem Solving in 2006

    OpenAIRE

    Pizlo, Zygmunt

    2007-01-01

    This paper presents a bibliography of a little more than 100 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo and Compendex databases. Only journal papers, books and dissertations are included. The topics include human development, education, neuroscience, research in applied settings, as well as animal studies. A few references from artificial intelligence are also given.

  5. Steam generators - problems and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Tapping, R.L

    1997-05-01

    Steam-generator problems, largely a consequence of corrosion and fouling, have resulted in increased inspection requirements and more regulatory attention to steam-generator integrity. In addition, utilities have had to develop steam-generator life-management strategies, including cleaning and replacement, to achieve design life. This paper summarizes the pertinent data to 1993/1994, and presents an overview of current steam-generator management practices. (author)

  6. Problems in decentralized data acquisition

    International Nuclear Information System (INIS)

    This paper describes INIS (International Nuclear Information System) which is operated by the International Atomic Energy Agency (IAEA) in collaboration with 73 Member States and 14 international organizations. INIS is a computerized system for collecting, processing and disseminating nuclear information. The collection and scanning of literature, input preparation and the dissemination of output are completely decentralized, the checking and merging of the information data are centralized. This paper shows the structure, management, processing and problem areas of this system. (Author)

  7. Fuel handling problems at KANUPP

    International Nuclear Information System (INIS)

    KANUPP experienced two abnormal fuel and fuel handling related problems during the year 1990. One of these had arisen due to development of end plate to end plate coupling between the two bundles at the leading end of the fuel string in channel HO2-S. The incident occurred when attempts were being made to fuel this channel. Due to pulling of sticking bundles into the acceptor fuelling machine (north) magazine, which was not designed to accommodate two bundles, a magazine rotary stop occurred. The forward motion of the charge tube was simultaneously discovered to be restricted. The incident led to stalling of fuelling machine locked on to the channel HO2, necessitating a reactor shut down. Removal of the fuelling machine was accomplished sometime later after draining of the channel. The second incident which made the fuelling of channel KO5-N temporarily inexecutable, occurred during attempts to remove its north end shield plug when this channel came up for fuelling. The incident resulted due to breaking of the lugs of the shield plug, making its withdrawal impossible. The Plant however kept operating with suspended fuelling of channel KO5, until it could no longer sustain a further increase in fuel burnup at the maximum rating position. Resolving both these problems necessitated draining of the respective channels, leaving the resident fuel uncovered for the duration of the associated operation. Due to substantial difference in the oxidation temperatures Of UO2 and Zircaloy and its influence as such on the cooling requirement, it was necessary either to determine explicitly that the respective channels did not contain defective fuel bundles or wait for time long enough to allow the decay heat to reduce to manageable proportions. This had a significant bearing on the Plant down time necessary for the rectification of the problems. This paper describes the two incidents in detail and dwells upon the measures adopted to resolve the related problems. (author)

  8. Evolutionary algorithms in multiobjective problems

    OpenAIRE

    Syomkin, A. M.; Zmitrovich, A. I.

    2003-01-01

    Many real-world problems involve two types of difficulties: 1) multiple, conflicting objectives and 2) a highly complex search space. Efficient evolutionary strategies have been developed to deal with both types of difficulties. Evolutionary algorithms possess several characteristics such as parallelism and robustness that make them preferable to classical optimization methods. In this work 1 conducted comparative studies among the well-known evolutionary algorithms based on NP-hard 0-1 multi...

  9. On Labeled Traveling Salesman Problems

    DEFF Research Database (Denmark)

    Couetoux, Basile; Gourves, Laurent; Monnot, Jerome;

    2008-01-01

    We consider labeled Traveling Salesman Problems, defined upon a complete graph of n vertices with colored edges. The objective is to find a tour of maximum (or minimum) number of colors. We derive results regarding hardness of approximation, and analyze approximation algorithms for both versions of...... the problem. For the maximization version we give a -approximation algorithm and show that it is APX-hard. For the minimization version, we show that it is not approximable within n 1 − ε for every ε> 0. When every color appears in the graph at most r times and r is an increasing function of n the...... problem is not O(r 1 − ε )-approximable. For fixed constant r we analyze a polynomial-time (r + H r )/2-approximation algorithm (H r is the r-th harmonic number), and prove APX-hardness. Analysis of the studied algorithms is shown to be tight....

  10. Inverse problems in systems biology

    International Nuclear Information System (INIS)

    Systems biology is a new discipline built upon the premise that an understanding of how cells and organisms carry out their functions cannot be gained by looking at cellular components in isolation. Instead, consideration of the interplay between the parts of systems is indispensable for analyzing, modeling, and predicting systems' behavior. Studying biological processes under this premise, systems biology combines experimental techniques and computational methods in order to construct predictive models. Both in building and utilizing models of biological systems, inverse problems arise at several occasions, for example, (i) when experimental time series and steady state data are used to construct biochemical reaction networks, (ii) when model parameters are identified that capture underlying mechanisms or (iii) when desired qualitative behavior such as bistability or limit cycle oscillations is engineered by proper choices of parameter combinations. In this paper we review principles of the modeling process in systems biology and illustrate the ill-posedness and regularization of parameter identification problems in that context. Furthermore, we discuss the methodology of qualitative inverse problems and demonstrate how sparsity enforcing regularization allows the determination of key reaction mechanisms underlying the qualitative behavior. (topical review)

  11. Solving the Wrong Hierarchy Problem

    CERN Document Server

    Blinov, Nikita

    2016-01-01

    Many theories require augmenting the Standard Model with additional scalar fields with large order one couplings. We present a new solution to the hierarchy problem for these scalar fields. We explore parity- and $\\mathbb{Z}_2$-symmetric theories where the Standard Model Higgs potential has two vacua. The parity or $\\mathbb{Z}_2$ copy of the Higgs lives in the minimum far from the origin while our Higgs occupies the minimum near the origin of the potential. This approach results in a theory with multiple light scalar fields but with only a single hierarchy problem, since the bare mass is tied to the Higgs mass by a discrete symmetry. The new scalar does not have a new hierarchy problem associated with it because its expectation value and mass are generated by dimensional transmutation of the scalar quartic coupling. The location of the second Higgs minimum is not a free parameter, but is rather a function of the matter content of the theory. As a result, these theories are extremely predictive. We develop thi...

  12. Elementary Investigation of Transportation Problems

    Directory of Open Access Journals (Sweden)

    Edit Schmidt

    2009-07-01

    Full Text Available For students learning the simplex method of linear programming it is a wellbelovedoccasion to solve the so-called transportation problem by the method ofdistribution. This method is simple to calculate and easy to follow. The simple way ofsolution suggests that its correctness may be proven by basic means. This paper has twomain aims. One of them is to present the problem and to solve it by basic means. The otherone is the analysis of the so-called array-bases defined for this reason. In case of atransportation problem m stores and n destinations are given, and the goods have to betaken from the stores to the destinations such that the cost of transporting has to beminimal. The unit costs of the transportation are given by an array. In the solution someroutes (elements of the array are chosen and the number of units to transport there isgiven. It will be proven that the routes for the optimal transportation compose a basis, andthe solution is also achieved by those through the searches. (The basis of an m n × arrayconsists of m+n−1 elements such that they do not span a loop. In the proof somecharacteristics of the bases are needed, for example that the number of them is finite. Toprove this it is enough to give an easily calculated upper bound, the exact value is given inthe appendix. As an extra result of this calculation some interesting formulas ofcombinatorics are also proven.

  13. On the Continuous CNN Problem

    CERN Document Server

    Augustine, John

    2010-01-01

    In the (discrete) CNN problem, online requests appear as points in $\\R^2$. Each request must be served before the next one is revealed. We have a server that can serve a request simply by aligning either its $x$ or $y$ coordinate with the request. The goal of the online algorithm is to minimize the total $L_1$ distance traveled by the server to serve all the requests. The best known competitive ratio for the discrete version is 879 (due to Sitters and Stougie). We study the continuous version, in which, the request can move continuously in $\\R^2$ and the server must continuously serve the request. A simple adversarial argument shows that the lower bound on the competitive ratio of any online algorithm for the continuous CNN problem is 3. Our main contribution is an online algorithm with competitive ratio $3+2 \\sqrt{3} \\approx 6.464$. Our analysis is tight. Since the continuous version is more general than the discrete orthogonal version of the CNN problem, our result improves upon the previous best known comp...

  14. Fibonacci's Triangle: A Vehicle for Problem Solving.

    Science.gov (United States)

    Ouellette, Hugh

    1979-01-01

    A method for solving certain types of problems is illustrated by problems related to Fibonacci's triangle. The method involves pattern recognition, generalizing, algebraic manipulation, and mathematical induction. (MP)

  15. Sociale problemer og sociale afvigelser - sociologisk set

    DEFF Research Database (Denmark)

    Henriksen, Lars Skov

    2002-01-01

    The arcticle presents central classical sociological theories of social problems and social deviance.......The arcticle presents central classical sociological theories of social problems and social deviance....

  16. Authentication: A Standard Problem or a Problem of Standards?

    Directory of Open Access Journals (Sweden)

    Amanda Capes-Davis

    2016-06-01

    Full Text Available Reproducibility and transparency in biomedical sciences have been called into question, and scientists have been found wanting as a result. Putting aside deliberate fraud, there is evidence that a major contributor to lack of reproducibility is insufficient quality assurance of reagents used in preclinical research. Cell lines are widely used in biomedical research to understand fundamental biological processes and disease states, yet most researchers do not perform a simple, affordable test to authenticate these key resources. Here, we provide a synopsis of the problems we face and how standards can contribute to an achievable solution.

  17. Authentication: A Standard Problem or a Problem of Standards?

    Science.gov (United States)

    2016-01-01

    Reproducibility and transparency in biomedical sciences have been called into question, and scientists have been found wanting as a result. Putting aside deliberate fraud, there is evidence that a major contributor to lack of reproducibility is insufficient quality assurance of reagents used in preclinical research. Cell lines are widely used in biomedical research to understand fundamental biological processes and disease states, yet most researchers do not perform a simple, affordable test to authenticate these key resources. Here, we provide a synopsis of the problems we face and how standards can contribute to an achievable solution. PMID:27300550

  18. Learning from the problems of problem-based learning

    Directory of Open Access Journals (Sweden)

    Epstein Richard

    2004-01-01

    Full Text Available Abstract Background The last decade has witnessed a rapid expansion of biomedical knowledge. Despite this, fashions in medical education over the same period have shifted away from factual (didactic teaching and towards contextual, or problem-based, learning (PBL. This paradigm shift has been justified by studies showing that PBL improves reasoning and communication while being associated with few if any detectable knowledge deficits. Discussion Analysis of the literature indicates that the recent rapid rise of PBL has closely paralleled the timing of the information explosion. The growing dominance of PBL could thus worsen the problems of information management in medical education via several mechanisms: first, by creating the impression that a defined spectrum of core factual knowledge suffices for clinical competence despite ongoing knowledge expansion (quality cost; second, by dissuading teachers from refining the educational utility of didactic modalities (improvement cost; and third, by reducing faculty time for developing reusable resources to impart factual knowledge more efficiently (opportunity cost. Summary These costs of PBL imply a need for strengthening the knowledge base of 21st-century medical graduates. New initiatives towards this end could include the development of more integrated cognitive techniques for facilitating the comprehension of complex data; the design of differentiated medical curricula for producing graduates with defined high-priority skill sets; and the encouragement of more cost-effective faculty teaching activities focused on the prototyping and testing of innovative commercializable educational tools.

  19. Indoor air problems in Asia

    International Nuclear Information System (INIS)

    Respiratory disease and mortality due to indoor air pollution are amongst the greatest environmental threats to health in the developing countries of Asia. World-wide, acute respiratory infection is the cause of death of at least 5 million children under the age of 5 every year. The World Bank has claimed that smoke from biomass fuels resulted in an estimated 4 million deaths annually amongst infants and children. Most of these deaths occur in developing countries. Combustion in its various forms must head the list of pollution sources in Asia. Combustion of various fuels for domestic heating, lighting and cooking comprises the major source of internally generated pollutants and combustion in industrial plants, power generation and transportation is the major cause of externally generated pollutants. The products of pyrolysis and combustion include many compounds with well-known adverse health effects. These include gases such as CO, CO2, NOx and SO2, volatile organic compounds such as polynuclear aromatic hydrocarbons and nitroamines as well as respirable particulates of variable composition. The nature and magnitude of the health risks posed by these materials vary with season, climate, location housing, method of ventilation, culture and socio-economic status. The most important cause of lung cancer in non-smokers in Northern Asia is the domestic combustion of smoky coal. Acute carbon monoxide poisoning is common in many Asian countries. Roads traffic exhaust pollution is worse in the major cities of South East Asia than almost anywhere else in the world and this externally generated air pollution forms the indoor air for the urban poor. Despite all these major problems there has been a tendency for international agencies to focus attention and resources on the more trivial problems of indoor air encountered in the affluent countries of the West. Regulatory agencies in Asia have been too frequently persuaded that their problems of indoor air pollution are

  20. Genetics problem solving and worldview

    Science.gov (United States)

    Dale, Esther

    The research goal was to determine whether worldview relates to traditional and real-world genetics problem solving. Traditionally, scientific literacy emphasized content knowledge alone because it was sufficient to solve traditional problems. The contemporary definition of scientific literacy is, "The knowledge and understanding of scientific concepts and processes required for personal decision-making, participation in civic and cultural affairs and economic productivity" (NRC, 1996). An expanded definition of scientific literacy is needed to solve socioscientific issues (SSI), complex social issues with conceptual, procedural, or technological associations with science. Teaching content knowledge alone assumes that students will find the scientific explanation of a phenomenon to be superior to a non-science explanation. Formal science and everyday ways of thinking about science are two different cultures (Palmer, 1999). Students address this rift with cognitive apartheid, the boxing away of science knowledge from other types of knowledge (Jedege & Aikenhead, 1999). By addressing worldview, cognitive apartheid may decrease and scientific literacy may increase. Introductory biology students at the University of Minnesota during fall semester 2005 completed a written questionnaire-including a genetics content-knowledge test, four genetic dilemmas, the Worldview Assessment Instrument (WAI) and some items about demographics and religiosity. Six students responded to the interview protocol. Based on statistical analysis and interview data, this study concluded the following: (1) Worldview, in the form of metaphysics, relates to solving traditional genetic dilemmas. (2) Worldview, in the form of agency, relates to solving traditional genetics problems. (3) Thus, worldview must be addressed in curriculum, instruction, and assessment.