WorldWideScience

Sample records for drugs methods problems

  1. Problems with drugs in Croatia.

    Science.gov (United States)

    Vrhovac, B

    1997-01-01

    Croatia has 4.8 million inhabitants, 11,800 physicians, 2000 pharmacists, two now shareholding, pharmaceutical companies (about 6500 employees, total sales of about 350 million US dollars). There are a number of problems due to the war (GNP fell from 3800 to about 1500 US dollars), occupation of 25% of its territory, 0.5 million refugees and lack of resources (139 US dollars/capita for health, about 40 US dollars i.e. 30%!! for drugs)--about three times less than before the aggression. The drug situation is controlled with the help of: (1) donations (approximate value of 600 million US dollars since 1991 from Europe and US), (2) (essential) drug formularies--250 for outpatients, and 580 generic names for various levels of hospital use, (3) special efforts to purchase drugs of good quality at a reasonable price (a kind of tender), (4) control of prescribing (prescriptions, specialists referral) especially by GPs. A new Medicines Act is in preparation and about 1000 generic names are on the market. DRUG EDUCATION: Pharmaca: the Croatian journal of pharmacotherapy has been published since 1962, there are several Drug bulletins (one published since 1975); special chapters on clinical pharmacology in textbooks, translation of three editions of Laurence's textbook with special commentary and adaptation to local needs; ADR spontaneous and intensive monitoring (WHO programme) with a personal feedback to the reporters and regular articles on drug use in a number of periodicals. Data on drug consumption indicates that there is room for improvement of prescribing. There is an enthusiasm for 'vasoactive drugs'--after dipirydamole came oxpentifylline and antimicrobials are always overprescribed. All these problems will hopefully decrease when the war finally stops and when industry (especially tourism) starts being fruitful again. In any case the importance of teaching of pharmacotherapy at the under- and postgraduate level should be recognized. Copyright 1997 by John Wiley

  2. Prescription drug abuse: problem, policies, and implications.

    Science.gov (United States)

    Phillips, Janice

    2013-01-01

    This article provides an overview on prescription drug abuse and highlights a number of related legislative bills introduced during the 112th Congress in response to this growing epidemic. Prescription drug abuse has emerged as the nation's fastest growing drug problem. Although prescription drugs have been used effectively and appropriately for decades, deaths from prescription pain medicine in particular have reached epidemic proportions. Bills related to prescription drug abuse introduced during the 112th Congress focus on strengthening provider and consumer education, tracking and monitoring prescription drug abuse, improving data collection on drug overdose fatalities, combating fraud and abuse in Medicare and Medicaid programs, reclassifying drugs to make them more difficult to prescribe and obtain, and enforcing stricter penalties for individuals who operate scam pain clinics and sell pain pills illegitimately. This article underscores the importance of a multifaceted approach to combating prescription drug abuse and concludes with implications for nursing. Copyright © 2013. Published by Mosby, Inc.

  3. Ethical problems arising from the use of placebo in clinical trials with drugs for migraine. Their analysis by the moral deliberation method.

    Science.gov (United States)

    Frías, J; Pascual, J; Lahuerta, J; Gracia, D; Dal-Ré, R

    2011-03-01

    Migraine is characterised as episodes of headache plus a variety of accompanying symptoms. Its pharmacological control remains unsatisfactory for some patients. The use of placebo in drug clinical trials on migraine commonly leads to numerous ethical uncertainties. The purpose of this paper is to illustrate how the deliberation method helps in analysing the issues and finding solutions to selected ethical problems. Ethical decisions that try to solve conflicts arising from placebo use in clinical trials may be adopted using the moral deliberation method. Thus, the conflict is systematically assessed by identifying the following: Relevant facts; Values in conflict; Duties, or in other words, possible courses of action. Moral duty is following the optimal course of action. To identify this, it is recommended to state extreme courses of action, then intermediate courses of action, and then to proceed to the optimal course(s) of action. In this paper, the application of this method is shown in several conflicting situations arising in two placebo-controlled clinical trials with drugs under development for the prophylaxis and acute treatment of migraine. Copyright © 2010 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  4. Pharmacist intervention in drug-related problems for patients with ...

    African Journals Online (AJOL)

    Purpose: To investigate the role of the community pharmacist in identifying, preventing and resolving drug related problems (DRPs) encountered by patients, with particular emphasis on cardiovascular drugs in community pharmacies in Northern Cyprus, Turkey. Methods: A prospective observational study for the ...

  5. Drug problem in southeast and southwest Asia.

    Science.gov (United States)

    Kulsudjarit, Kongpetch

    2004-10-01

    In 2002, the drug problem in Southeast and Southwest Asia was serious, particularly in the production of opium and heroin in Afghanistan, Myanmar, and Laos, the three largest producers of illicit opium in the world. The increasing illicit manufacture of ATS, particularly methamphetamine, in Southeast Asia, mainly in China and Myanmar, was also a major concern. Some reports indicated that ephedrine, used for illicitly producing methamphetamine in Southeast Asia, is diverted and smuggled out of China and India, whereas caffeine, the adulterant used for producing methamphetamine tablets, is mainly smuggled into Myanmar through its border with Thailand. Seizure data showed a dramatic increase in trafficking in MDMA through Southeast Asia. In terms of the drug epidemic, in 2002, cannabis remained overall the main drug of abuse in all of the countries of Southeast and Southwest Asia. Opiates, mainly opium and heroin, were also the drugs of choice except in Thailand, where opiate abuse declined, but ATS was the main drug of abuse due to its low cost and availability. A significant increase in ATS abuse, amphetamine, methamphetamine, and MDMA among the youth who smoked, sniffed, and inhaled them was reported in Cambodia, China, Indonesia, Laos, Myanmar, the Philippines, and Thailand. Injecting drug use among opiate abusers has been identified as the prime cause of the rapid spread of HIV/AIDS in Southeast and Southwest Asia.

  6. Drug-related problems and pharmacy interventions in community practice

    DEFF Research Database (Denmark)

    Westerlund, Tommy; Almarsdóttir, Anna Birna; Melander, Arne

    1999-01-01

    Objectives. (1) To document types and number of drug-related problems identified by community pharmacy personnel in Sweden; (2) to determine relationships among the types and number of problems identified and the gender, age and number of prescribed drugs in patients; and (3) to document the inte......Objectives. (1) To document types and number of drug-related problems identified by community pharmacy personnel in Sweden; (2) to determine relationships among the types and number of problems identified and the gender, age and number of prescribed drugs in patients; and (3) to document...... the interventions made by pharmacy personnel with patients and prescribers. Method. Random samples of pharmacists, prescriptionists and pharmacy technicians were drawn nationwide in Sweden; 144 (63 per cent) of the employees fulfilling the inclusion criteria agreed to take part. The participants documented drug......-related problems, interventions and patient variables on a data collection form, and tallied the number of patients they served on another form. Setting. One hundred and sixteen community pharmacies and 12 outpatient hospital pharmacies. Key findings. One problem or more was identified among 2.5 per cent...

  7. Least bad solutions to the 'drugs problem'.

    Science.gov (United States)

    Mugford, S

    1991-01-01

    This paper examines the current difficulties being faced in Australia by policy-makers attempting to regulate the non-medical use of illegal drugs, and it is suggested that the difficulties centre upon two aspects. First, existing prohibitions are unsuccessful, with use levels rising and, in some arenas (e.g. cocaine use in the USA), quite out of control. On the other hand, a move towards decriminalization or legalization is difficult because past propaganda has been so vehement that a change now apparently risks sending the wrong messages to young people. This dilemma means that there is no solution, including inertia, which is risk-free, nor is there one free of difficulties. It is thus relevant to think in terms of 'least bad' rather than 'best' when formulating a system to face these problems. The exploration of what this least bad solution might be begins with the examination of the prominent myths (such as 'the drug-free society', 'the evil pusher', 'the user as victim' and 'the young person as cultural dope') that hinder our reasoning. Secondly, by suggesting that, in a climate of increasing crime related to drugs, inability of prohibitions to control that use and escalating health risks attendant on use (including the AIDS problem), the central policy thrust must be harm reduction and damage minimization rather than illusory goals such as widespread abstinence. The paper concludes with a discussion of some relevant evidence on alternative options.

  8. Ingenious mathematical problems and methods

    CERN Document Server

    Graham, Louis A

    2013-01-01

    Collection of 100 of the best submissions to a math puzzle column features problems in engineering situations, logic, number theory, and geometry. Most solutions include details of several different methods.

  9. Computational methods in drug discovery

    Directory of Open Access Journals (Sweden)

    Sumudu P. Leelananda

    2016-12-01

    Full Text Available The process for drug discovery and development is challenging, time consuming and expensive. Computer-aided drug discovery (CADD tools can act as a virtual shortcut, assisting in the expedition of this long process and potentially reducing the cost of research and development. Today CADD has become an effective and indispensable tool in therapeutic development. The human genome project has made available a substantial amount of sequence data that can be used in various drug discovery projects. Additionally, increasing knowledge of biological structures, as well as increasing computer power have made it possible to use computational methods effectively in various phases of the drug discovery and development pipeline. The importance of in silico tools is greater than ever before and has advanced pharmaceutical research. Here we present an overview of computational methods used in different facets of drug discovery and highlight some of the recent successes. In this review, both structure-based and ligand-based drug discovery methods are discussed. Advances in virtual high-throughput screening, protein structure prediction methods, protein–ligand docking, pharmacophore modeling and QSAR techniques are reviewed.

  10. Problems Associated With Substandard And Counterfeit Drugs In ...

    African Journals Online (AJOL)

    Problems Associated With Substandard And Counterfeit Drugs In Developing Countries: A Review Article On Global Implications Of Counterfeit Drugs In The Era Of Anti-Retroviral (ARVS) Drugs In A Free Market Economy.

  11. 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, ...

  12. Drug-related problems in patients with osteoporosis

    Directory of Open Access Journals (Sweden)

    Ilić Darko

    2016-01-01

    Full Text Available Background/Aim. Drug-related problems are especially frequent among patients suffering from non-communicable diseases, like osteoporosis, leading to suboptimal treatment response. The aim of this study was to identify drug-related problems in patients with osteoporosis. Methods. This cross-sectional prospective study was conducted in January 2014 on outpatients with osteoporosis from three health facilities in Belgrade, Serbia. The patients included in the study were older than 50 years, and they were offered an anonymous questionnaire with open-ended questions. Results. There were 355 study participants, 329 (92.7% females and 26 (7.3% males. The patients who experienced at least one osteoporotic fracture (n = 208 were significantly less adherent to the therapy, less engaged in sports and regular physical activities, and more prone to nutrition with inadequate intake of calcium and vitamin D than patients without fractures (n = 147. Conclusion. The effectiveness of osteoporosis treatment is decreased by several drug-related problems encountered by both physicians and patients. However, the majority of the drug-related problems could be greatly influenced by appropriate educational programs. [Projekat Ministarstva nauke Republike Srbije, br. 175007

  13. Multigrid Methods for EHL Problems

    Science.gov (United States)

    Nurgat, Elyas; Berzins, Martin

    1996-01-01

    In many bearings and contacts, forces are transmitted through thin continuous fluid films which separate two contacting elements. Objects in contact are normally subjected to friction and wear which can be reduced effectively by using lubricants. If the lubricant film is sufficiently thin to prevent the opposing solids from coming into contact and carries the entire load, then we have hydrodynamic lubrication, where the lubricant film is determined by the motion and geometry of the solids. However, for loaded contacts of low geometrical conformity, such as gears, rolling contact bearings and cams, this is not the case due to high pressures and this is referred to as Elasto-Hydrodynamic Lubrication (EHL) In EHL, elastic deformation of the contacting elements and the increase in fluid viscosity with pressure are very significant and cannot be ignored. Since the deformation results in changing the geometry of the lubricating film, which in turn determines the pressure distribution, an EHL mathematical model must simultaneously satisfy the complex elasticity (integral) and the Reynolds lubrication (differential) equations. The nonlinear and coupled nature of the two equations makes numerical calculations computationally intensive. This is especially true for highly loaded problems found in practice. One novel feature of these problems is that the solution may exhibit sharp pressure spikes in the outlet region. To this date both finite element and finite difference methods have been used to solve EHL problems with perhaps greater emphasis on the use of the finite difference approach. In both cases, a major computational difficulty is ensuring convergence of the nonlinear equations solver to a steady state solution. Two successful methods for achieving this are direct iteration and multigrid methods. Direct iteration methods (e.g Gauss Seidel) have long been used in conjunction with finite difference discretizations on regular meshes. Perhaps one of the best examples of

  14. Some problems on Monte Carlo method development

    International Nuclear Information System (INIS)

    Pei Lucheng

    1992-01-01

    This is a short paper on some problems of Monte Carlo method development. The content consists of deep-penetration problems, unbounded estimate problems, limitation of Mdtropolis' method, dependency problem in Metropolis' method, random error interference problems and random equations, intellectualisation and vectorization problems of general software

  15. Pharmacist intervention in drug-related problems for patients with ...

    African Journals Online (AJOL)

    Trop J Pharm Res, October 2016; 15(10): 2275. Tropical Journal of ... medication errors in irrational drug use, while patient adherence ..... Drug-related problems identified from geriatric medication safety ... Ann. Pharmacother. 2005; 39:1423-.

  16. Drug Pollution - The Problem of Abuse*

    African Journals Online (AJOL)

    at this stage, is to educate the public in the dangers of ... embroiled in a rebellion against 'The Establishment', where ... incidence of addicts, varying with the type of drug, to be .... behaviour disturbances. ... and personality disturbances.75.

  17. Subcutaneous drug infusions: a review of problems and solutions.

    Science.gov (United States)

    Mitten, T

    2001-02-01

    Subcutaneous drug infusion using a portable syringe driver has had a significant impact on patient comfort in palliative care. It permits the continuous delivery of a range of drug therapies, so bypassing problems of dysphagia, weakness and the inability of many patients in the terminal phase to take oral medication. The devices are not problem-free, however. Mechanical problems, reactions at the infusion site and difficulties with the mixing of drugs in the syringe are all widely recognized. This article reviews some general issues with the operation of portable syringe drivers, and discusses a range of potential problems and their solutions.

  18. Drug related problems with Antiparkinsonian agents: consumer Internet reports versus published data.

    Science.gov (United States)

    Schröder, Sabrina; Zöllner, York Francis; Schaefer, Marion

    2007-10-01

    There is currently a lack of detailed information concerning drug related problems in the outpatient treatment of Parkinson's disease. Problems associated with drug treatment communicated anonymously in Parkinson's disease online forums were therefore retrospectively searched and documented for 1 year. Based on postings concerning 12 drugs for the treatment of Parkinson's disease, a total of 238 drug related problems were identified and categorised using the Problem Intervention Documentation (PI-Doc). Of these, 153 were adverse drug reactions. Adverse drug reactions associated with the skin were relatively common, but central effects such as cognitive or psychiatric changes, effects on the sleep/waking system and other problems like headache and dizziness accounted for the highest percentage of adverse events. A comparison with data from scientific literature revealed a number of differences. This means that an analysis of online forums detected a number of drug related problems that were otherwise largely invisible. These were mainly associated with the qualitative aspects of treatment such as medication handling, dosage and individual problems concerning adverse events. In addition, the described method of identifying and classifying drug related problems in Internet forums may also be seen as a contribution to the international discussion about consumer reports and pharmacovigilance. The information about adverse drug reactions given by Internet users can be seen as a valuable adjunct to clinical trial data and as being very timely with regard to the event itself. Online forums may be considered as a suitable source of observational information to complement data from randomised clinical trials.

  19. Computational methods in drug discovery

    OpenAIRE

    Sumudu P. Leelananda; Steffen Lindert

    2016-01-01

    The process for drug discovery and development is challenging, time consuming and expensive. Computer-aided drug discovery (CADD) tools can act as a virtual shortcut, assisting in the expedition of this long process and potentially reducing the cost of research and development. Today CADD has become an effective and indispensable tool in therapeutic development. The human genome project has made available a substantial amount of sequence data that can be used in various drug discovery project...

  20. Dealing with Drug Problems: Preventing and Treating Drug Abuse

    Science.gov (United States)

    ... Pittsburgh is looking at whether teaching healthy caregiving strategies to parents can help promote self-regulation skills in children and prevent substance abuse later on. Starting when children are two years old, Shaw’s study enrolls families at risk of substance use problems ...

  1. 2010 drug packaging review: identifying problems to prevent errors.

    Science.gov (United States)

    2011-06-01

    Prescrire's analyses showed that the quality of drug packaging in 2010 still left much to be desired. Potentially dangerous packaging remains a significant problem: unclear labelling is source of medication errors; dosing devices for some psychotropic drugs create a risk of overdose; child-proof caps are often lacking; and too many patient information leaflets are misleading or difficult to understand. Everything that is needed for safe drug packaging is available; it is now up to regulatory agencies and drug companies to act responsibly. In the meantime, health professionals can help their patients by learning to identify the pitfalls of drug packaging and providing safe information to help prevent medication errors.

  2. Evaluation of drug therapy problems among renal patients receiving ...

    African Journals Online (AJOL)

    Adibe et al. Trop J Pharm Res, March 2017; 16(3): 697 .... suggestions to address medication problems, ..... Preventable drug-related hospital admissions. Ann. Pharmacother. 2002;. 36: .... geriatric hospitalized patients in yogyakarta hospitals,.

  3. Pervasive developmental disorder, behavior problems, and psychotropic drug use in children and adolescents with mental retardation.

    NARCIS (Netherlands)

    Bildt, de A.; Mulder, E.J.; Scheers, T.; Minderaa, R.B.; Tobi, H.

    2006-01-01

    OBJECTIVE. This study investigated the interrelationship between psychopharmacotherapy in general and the use of specific psychotropic drugs and pervasive developmental disorder and other behavior problems in children and adolescents with mental retardation. METHODS. A total of 862 participants 4 to

  4. A survey of drug abuse problems among students of selected ...

    African Journals Online (AJOL)

    The purpose of the study was to survey drug abuse problems among students of selected secondary schools in Ile-Ife in Osun State. Specifically, the study was to find out the reasons for drug abuse among students. The major instrument used to collect needed information was the questionnaire which was distributed to ...

  5. Characteristics of potential drug-related problems among oncology patients

    NARCIS (Netherlands)

    Bulsink, Arjan; Imholz, Alex L. T.; Brouwers, Jacobus R. B. J.; Jansman, Frank G. A.

    Background Oncology patients are more at risk for drug related problems because of treatment with (combinations of) anticancer drugs, as they have a higher risk for organ failure or altered metabolism with progression of their disease. Objective The aim of this study was to characterize and to

  6. Prisoners' views about the drugs problem in prisons, and the new Prison Service drug strategy.

    Science.gov (United States)

    Gore, S M; Bird, A G; Cassidy, J

    1999-09-01

    Three hundred and seventy-five out of 575 prisoners (222/299 drug users and 153/267 non-users) who responded to a self-completion health care questionnaire at two prisons in 1997 commented on drugs in prisons. One hundred and forty-eight out of 176 responses expressed negative opinions about mandatory drugs testing (MDT), and 107 said that MDT promoted switching to or increased use of heroin/hard drugs'. Sixty-two prisoners suggested that more help/counselling was needed for drug users, 52 segregation of drug users/drug-free wings, and 50 more security on visits/in corridors after medication. The new Prison Service drug strategy has revised random MDT. It targets those who supply drugs, and supports those who want to stop using drugs, and accords with prisoners' views about the heroin problem in prisons.

  7. Relating Actor Analysis Methods to Policy Problems

    NARCIS (Netherlands)

    Van der Lei, T.E.

    2009-01-01

    For a policy analyst the policy problem is the starting point for the policy analysis process. During this process the policy analyst structures the policy problem and makes a choice for an appropriate set of methods or techniques to analyze the problem (Goeller 1984). The methods of the policy

  8. Off-Label Drug Use in Pediatric Practice: Unsolved Problems

    Directory of Open Access Journals (Sweden)

    A. R. Titova

    2015-01-01

    Full Text Available The widespread «off-label» drug use and the prescribing of unlicensed medicines in pediatric practice is a major health problem. The authors discuss actual regulatory and legal issues of «off-label» drug use in children in the US, Europe and Russia. The results of different population-based studies from many countries, showing the structure and frequency of «off-label» drug use in children, are summarized in this article. It is shown that such practice increases the risk of adverse drug reactions. The authors offer practical recommendations for a safer use of drugs in pediatric practice. The priority issue is conducting high quality clinical trials with the participation of children, improving national pharmacovigilance and the monitoring of off-label drug use, developing pediatric formularies, improving doctors’ knowledge and awareness of safety and efficacy of medicines in pediatric population.

  9. Drug problems in contemporary China: a profile of Chinese drug users in a metropolitan area.

    Science.gov (United States)

    Huang, Kaicheng; Zhang, Lening; Liu, Jianhong

    2011-03-01

    Drug problems are reemerging in China since the nation implemented economic reform and an "open door" policy in the early 1980s. This is causing both national and international concern. However, knowledge and understanding of the Chinese drug problem is fairly limited because of the nation's unique social and political history. In response to this shortage of information, our study presents a profile of Chinese drug users. Data were collected from a survey of drug users attending mandatory treatment centres in a large city in 2009. We present a demographic profile of the drug users, describe their patterns of drug use, their access to drugs and their history of drug treatment. Chinese drug users, like those from the U.S., are likely to be unemployed and have a low level of education. However, they are more likely than those in the U.S. to use heroin, Bingdu (methamphetamine) and Maguo (a derivative of methamphetamine), and they pay less for their drugs. This profile of drug users is informative and valuable for drug prevention, intervention, and treatment in the Chinese setting because knowing and understanding the drug population is essential for effective control. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. The Swedish drug problem: Conceptual understanding and problem handling, 1839–2011

    Directory of Open Access Journals (Sweden)

    Edman Johan

    2014-12-01

    Full Text Available AIM - To analyse the Swedish drug question by examining dominant concepts used to portray the problem in the years 1839-2011. Theoretically, we understand these concepts as ideological tools that shape the political initiatives and administrative efforts to deal with the problem. The study is based on two kinds of source material: articles in medical journals from the years 1839-1964 and public reports on vagrancy, the alcohol problem, mental health and the drug problem from the years 1882-2011.

  11. Estimating incidence of problem drug use using the Horwitz-Thompson estimator - A new approach applied to people who inject drugs in Oslo 1985-2008.

    Science.gov (United States)

    Amundsen, Ellen J; Bretteville-Jensen, Anne L; Kraus, Ludwig

    2016-01-01

    The trend in the number of new problem drug users per year (incidence) is the most important measure for studying the diffusion of problem drug use. Due to sparse data sources and complicated statistical models, estimation of incidence of problem drug use is challenging. The aim of this study is to widen the palette of available methods and data types for estimating incidence of problem drug use over time, and for identifying the trends. This study presents a new method of incidence estimation, applied to people who inject drugs (PWID) in Oslo. The method took into account the transition between different phases of drug use progression - active use, temporary cessation, and permanent cessation. The Horwitz-Thompson estimator was applied. Data included 16 cross-sectional samples of problem drug users who reported their onset of injecting drug use. We explored variation in results for selected probable scenarios of parameter variation for disease progression, as well as the stability of the results based on fewer years of cross-sectional samples. The method yielded incidence estimates of problem drug use, over time. When applied to people in Oslo who inject drugs, we found a significant reduction of incidence of 63% from 1985 to 2008. This downward trend was also present when the estimates were based on fewer surveys (five) and in the results of sensitivity analysis for likely scenarios of disease progression. This new method, which incorporates temporarily inactive problem drug users, may become a useful tool for estimating the incidence of problem drug use over time. The method may be less data intensive than other methods based on first entry to treatment and may be generalized to other groups of substance users. Further studies on drug use progression would improve the validity of the results. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Problem Solving Methods in Engineering Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1999-01-01

    This short paper discusses typical engineering tasks and problem solving methods, based on a field study of engineering tasks at a Danish engineering firm. The field study has identified ten classes of design tasks and in this paper these classes are related to problem solving methods. The descri...

  13. Drug Pollution - The Problem of Abuse | Bensusan | South African ...

    African Journals Online (AJOL)

    Some of the aetiological factors are given as well as an outline of the extent of drug abuse in many countries, age of addiction and also the role of the medical practitioner. The main problem facing the profession in South Africa, at this stage, is to educate the public in the dangers of dagga. Five principles are ...

  14. a survey on drug related problems in cervical cancer patients

    African Journals Online (AJOL)

    userpc

    Cisplatin/5FU/paclitaxel. 6. 9.23. 6. Seizure. Cisplatin. 2. 3.08. 7. Loss of hair. Cisplatin/5FU/Paclitaxel. 3. 4.62. 8. Nephrotoxicity. Cisplatin. 3. 4.62. 9. Hypotension. Paclitaxel. 3. 4.62. TOTAL. 65. 100. Table 3: Relationship between cervical cancer patients' factors and DRPs. Patients Factor. Drug Related Problems (DRPs).

  15. Drug Therapy Problems in Patients on Antihypertensives and ...

    African Journals Online (AJOL)

    Drug therapy problems (DTPs), with the associated risks inherent in antihypertensive and antidiabetic therapy require utmost attention. This present study was aimed at assessing the DTPs observed in the management of hypertension and diabetes mellitus (DM) in two tertiary health facilities in Niger Delta region. In this ...

  16. Pharmacists' Intervention to Reduce Drug Related Problems in HIV ...

    African Journals Online (AJOL)

    Despite advances in the use of highly active antiretroviral therapy (HAART) in the management of HIV/AIDS, drug-related problems (DRPs) still remain an issue, particularly in developing countries. This study evaluated the incidence of DRPs among HIV/AIDS patients in a HIV/AIDS care centre in southern Nigeria and the ...

  17. Helping someone with problem drug use: a delphi consensus study of consumers, carers, and clinicians

    Directory of Open Access Journals (Sweden)

    Kelly Claire M

    2011-01-01

    Full Text Available Abstract Background Problem use of illicit drugs (i.e. drug abuse or dependence is associated with considerable health and social harms, highlighting the need for early intervention and engagement with health services. Family members, friends and colleagues play an important role in supporting and assisting individuals with problem drug use to seek professional help, however there are conflicting views about how and when such support should be offered. This paper reports on the development of mental health first aid guidelines for problem drug use in adults, to help inform community members on how to assist someone developing problem drug use or experiencing a drug-related crisis. Methods A systematic review of the scientific and lay literature was conducted to develop a 228-item survey containing potential first-aid strategies to help someone developing a drug problem or experiencing a drug-related crisis. Three panels of experts (29 consumers, 31 carers and 27 clinicians were recruited from Australia, Canada, New Zealand, the United Kingdom, and the United States. Panel members independently rated the items over three rounds, with strategies reaching consensus on importance written into the guidelines. Results The overall response rate across three rounds was 80% (86% consumers, 81% carers, 74% clinicians. 140 first aid strategies were endorsed as essential or important by 80% or more of panel members. The endorsed strategies provide information and advice on what is problem drug use and its consequences, how to approach a person about their problem drug use, tips for effective communication, what to do if the person is unwilling to change their drug use, what to do if the person does (or does not want professional help, what are drug-affected states and how to deal with them, how to deal with adverse reactions leading to a medical emergency, and what to do if the person is aggressive. Conclusions The guidelines provide a consensus

  18. New method for solving multidimensional scattering problem

    International Nuclear Information System (INIS)

    Melezhik, V.S.

    1991-01-01

    A new method is developed for solving the quantum mechanical problem of scattering of a particle with internal structure. The multichannel scattering problem is formulated as a system of nonlinear functional equations for the wave function and reaction matrix. The method is successfully tested for the scattering from a nonspherical potential well and a long-range nonspherical scatterer. The method is also applicable to solving the multidimensional Schroedinger equation with a discrete spectrum. As an example the known problem of a hydrogen atom in a homogeneous magnetic field is analyzed

  19. Waring's Problem and the Circle Method

    Indian Academy of Sciences (India)

    other interests include classical music and mountaineering. the problems they worked on. Their proof of a slightly. Keywords weaker form of Ramanujan's original formula was pub-. Waring's problem, circle method, ... arc is fairly simple while it is the minor arc estimation that accounts for the 'major' amount of work involved!

  20. Numerical methods for hyperbolic differential functional problems

    Directory of Open Access Journals (Sweden)

    Roman Ciarski

    2008-01-01

    Full Text Available The paper deals with the initial boundary value problem for quasilinear first order partial differential functional systems. A general class of difference methods for the problem is constructed. Theorems on the error estimate of approximate solutions for difference functional systems are presented. The convergence results are proved by means of consistency and stability arguments. A numerical example is given.

  1. Lavine method applied to three body problems

    International Nuclear Information System (INIS)

    Mourre, Eric.

    1975-09-01

    The methods presently proposed for the three body problem in quantum mechanics, using the Faddeev approach for proving the asymptotic completeness, come up against the presence of new singularities when the potentials considered v(α)(x(α)) for two-particle interactions decay less rapidly than /x(α)/ -2 ; and also when trials are made for solving the problem with a representation space whose dimension for a particle is lower than three. A method is given that allows the mathematical approach to be extended to three body problem, in spite of singularities. Applications are given [fr

  2. Methods of solving sequence and series problems

    CERN Document Server

    Grigorieva, Ellina

    2016-01-01

    This book aims to dispel the mystery and fear experienced by students surrounding sequences, series, convergence, and their applications. The author, an accomplished female mathematician, achieves this by taking a problem solving approach, starting with fascinating problems and solving them step by step with clear explanations and illuminating diagrams. The reader will find the problems interesting, unusual, and fun, yet solved with the rigor expected in a competition. Some problems are taken directly from mathematics competitions, with the name and year of the exam provided for reference. Proof techniques are emphasized, with a variety of methods presented. The text aims to expand the mind of the reader by often presenting multiple ways to attack the same problem, as well as drawing connections with different fields of mathematics. Intuitive and visual arguments are presented alongside technical proofs to provide a well-rounded methodology. With nearly 300 problems including hints, answers, and solutions,Met...

  3. Path optimization method for the sign problem

    Directory of Open Access Journals (Sweden)

    Ohnishi Akira

    2018-01-01

    Full Text Available We propose a path optimization method (POM to evade the sign problem in the Monte-Carlo calculations for complex actions. Among many approaches to the sign problem, the Lefschetz-thimble path-integral method and the complex Langevin method are promising and extensively discussed. In these methods, real field variables are complexified and the integration manifold is determined by the flow equations or stochastically sampled. When we have singular points of the action or multiple critical points near the original integral surface, however, we have a risk to encounter the residual and global sign problems or the singular drift term problem. One of the ways to avoid the singular points is to optimize the integration path which is designed not to hit the singular points of the Boltzmann weight. By specifying the one-dimensional integration-path as z = t +if(t(f ϵ R and by optimizing f(t to enhance the average phase factor, we demonstrate that we can avoid the sign problem in a one-variable toy model for which the complex Langevin method is found to fail. In this proceedings, we propose POM and discuss how we can avoid the sign problem in a toy model. We also discuss the possibility to utilize the neural network to optimize the path.

  4. Problems in the regulatory policy of the drug market

    Science.gov (United States)

    Miziara, Nathália Molleis; Coutinho, Diogo Rosenthal

    2015-01-01

    OBJECTIVE Analyze the implementation of drug price regulation policy by the Drug Market Regulation Chamber. METHODS This is an interview-based study, which was undertaken in 2012, using semi-structured questionnaires with social actors from the pharmaceutical market, the pharmaceuticals industry, consumers and the regulatory agency. In addition, drug prices were compiled based on surveys conducted in the state of Sao Paulo, at the point of sale, between February 2009 and May 2012. RESULTS The mean drug prices charged at the point of sale (pharmacies) were well below the maximum price to the consumer, compared with many drugs sold in Brazil. Between 2009 and 2012, 44 of the 129 prices, corresponding to 99 drugs listed in the database of compiled prices, showed a variation of more than 20.0% in the mean prices at the point of sale and the maximum price to the consumer. In addition, many laboratories have refused to apply the price adequacy coefficient in their sales to government agencies. CONCLUSIONS The regulation implemented by the pharmaceutical market regulator was unable to significantly control prices of marketed drugs, without succeeding to push them to levels lower than those determined by the pharmaceutical industry and failing, therefore, in its objective to promote pharmaceutical support for the public. It is necessary reconstruct the regulatory law to allow market prices to be reduced by the regulator as well as institutional strengthen this government body. PMID:26083945

  5. Collaborative Problem Solving Methods towards Critical Thinking

    Science.gov (United States)

    Yin, Khoo Yin; Abdullah, Abdul Ghani Kanesan; Alazidiyeen, Naser Jamil

    2011-01-01

    This research attempts to examine the collaborative problem solving methods towards critical thinking based on economy (AE) and non economy (TE) in the SPM level among students in the lower sixth form. The quasi experiment method that uses the modal of 3X2 factorial is applied. 294 lower sixth form students from ten schools are distributed…

  6. Qualitative Methods in Drug Utilization Research

    DEFF Research Database (Denmark)

    Almarsdóttir, Anna Birna; Bastholm Rahmner, Pia

    2016-01-01

    Qualitative research methods derive from the social sciences. Their use in drug utilization research is increasingly widespread, especially in understanding patient and prescriber perspectives. The main focus in qualitative research is exploration of a given phenomenon in order to get a wider...... understanding of why and how it appears. Qualitative research methods build on various theoretical underpinnings/schools of thought. The same validity and quality criteria cannot be used for both qualitative and quantitative methods....

  7. 49 CFR 40.205 - How are drug test problems corrected?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false How are drug test problems corrected? 40.205 Section 40.205 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.205 How are drug test problems...

  8. Potential and problems in ultrasound-responsive drug delivery systems

    Directory of Open Access Journals (Sweden)

    Zhao YZ

    2013-04-01

    Full Text Available Ying-Zheng Zhao,1,3 Li-Na Du,2 Cui-Tao Lu,1 Yi-Guang Jin,2 Shu-Ping Ge3 1Wenzhou Medical College, Wenzhou City, Zhejiang Province, 2Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China; 3St Christopher’s Hospital for Children/Drexel University College of Medicine, Philadelphia, PA, USA Abstract: Ultrasound is an important local stimulus for triggering drug release at the target tissue. Ultrasound-responsive drug delivery systems (URDDS have become an important research focus in targeted therapy. URDDS include many different formulations, such as microbubbles, nanobubbles, nanodroplets, liposomes, emulsions, and micelles. Drugs that can be loaded into URDDS include small molecules, biomacromolecules, and inorganic substances. Fields of clinical application include anticancer therapy, treatment of ischemic myocardium, induction of an immune response, cartilage tissue engineering, transdermal drug delivery, treatment of Huntington’s disease, thrombolysis, and disruption of the blood–brain barrier. This review focuses on recent advances in URDDS, and discusses their formulations, clinical application, and problems, as well as a perspective on their potential use in the future. Keywords: ultrasound, targeted therapy, clinical application

  9. Pervasive developmental disorder, behavior problems, and psychotropic drug use in children and adolescents with mental retardation

    NARCIS (Netherlands)

    de Bildt, Annelies; Mulder, Erik J.; Scheers, Tom; Minderaa, Ruud B.; Tobi, Hilde

    2006-01-01

    OBJECTIVE. This study investigated the interrelationship between psychopharmaco-therapy in general and the use of specific psychotropic drugs and pervasive developmental disorder and other behavior problems in children and adolescents with mental retardation. METHODS. A total of 862 participants 4

  10. Time-dependent problems and difference methods

    CERN Document Server

    Gustafsson, Bertil; Oliger, Joseph

    2013-01-01

    Praise for the First Edition "". . . fills a considerable gap in the numerical analysis literature by providing a self-contained treatment . . . this is an important work written in a clear style . . . warmly recommended to any graduate student or researcher in the field of the numerical solution of partial differential equations."" -SIAM Review Time-Dependent Problems and Difference Methods, Second Edition continues to provide guidance for the analysis of difference methods for computing approximate solutions to partial differential equations for time-de

  11. Finite element methods for incompressible flow problems

    CERN Document Server

    John, Volker

    2016-01-01

    This book explores finite element methods for incompressible flow problems: Stokes equations, stationary Navier-Stokes equations, and time-dependent Navier-Stokes equations. It focuses on numerical analysis, but also discusses the practical use of these methods and includes numerical illustrations. It also provides a comprehensive overview of analytical results for turbulence models. The proofs are presented step by step, allowing readers to more easily understand the analytical techniques.

  12. Computational methods in calculating superconducting current problems

    Science.gov (United States)

    Brown, David John, II

    Various computational problems in treating superconducting currents are examined. First, field inversion in spatial Fourier transform space is reviewed to obtain both one-dimensional transport currents flowing down a long thin tape, and a localized two-dimensional current. The problems associated with spatial high-frequency noise, created by finite resolution and experimental equipment, are presented, and resolved with a smooth Gaussian cutoff in spatial frequency space. Convergence of the Green's functions for the one-dimensional transport current densities is discussed, and particular attention is devoted to the negative effects of performing discrete Fourier transforms alone on fields asymptotically dropping like 1/r. Results of imaging simulated current densities are favorably compared to the original distributions after the resulting magnetic fields undergo the imaging procedure. The behavior of high-frequency spatial noise, and the behavior of the fields with a 1/r asymptote in the imaging procedure in our simulations is analyzed, and compared to the treatment of these phenomena in the published literature. Next, we examine calculation of Mathieu and spheroidal wave functions, solutions to the wave equation in elliptical cylindrical and oblate and prolate spheroidal coordinates, respectively. These functions are also solutions to Schrodinger's equations with certain potential wells, and are useful in solving time-varying superconducting problems. The Mathieu functions are Fourier expanded, and the spheroidal functions expanded in associated Legendre polynomials to convert the defining differential equations to recursion relations. The infinite number of linear recursion equations is converted to an infinite matrix, multiplied by a vector of expansion coefficients, thus becoming an eigenvalue problem. The eigenvalue problem is solved with root solvers, and the eigenvector problem is solved using a Jacobi-type iteration method, after preconditioning the

  13. Monte Carlo method in radiation transport problems

    International Nuclear Information System (INIS)

    Dejonghe, G.; Nimal, J.C.; Vergnaud, T.

    1986-11-01

    In neutral radiation transport problems (neutrons, photons), two values are important: the flux in the phase space and the density of particles. To solve the problem with Monte Carlo method leads to, among other things, build a statistical process (called the play) and to provide a numerical value to a variable x (this attribution is called score). Sampling techniques are presented. Play biasing necessity is proved. A biased simulation is made. At last, the current developments (rewriting of programs for instance) are presented due to several reasons: two of them are the vectorial calculation apparition and the photon and neutron transport in vacancy media [fr

  14. Ensemble Kalman methods for inverse problems

    International Nuclear Information System (INIS)

    Iglesias, Marco A; Law, Kody J H; Stuart, Andrew M

    2013-01-01

    The ensemble Kalman filter (EnKF) was introduced by Evensen in 1994 (Evensen 1994 J. Geophys. Res. 99 10143–62) as a novel method for data assimilation: state estimation for noisily observed time-dependent problems. Since that time it has had enormous impact in many application domains because of its robustness and ease of implementation, and numerical evidence of its accuracy. In this paper we propose the application of an iterative ensemble Kalman method for the solution of a wide class of inverse problems. In this context we show that the estimate of the unknown function that we obtain with the ensemble Kalman method lies in a subspace A spanned by the initial ensemble. Hence the resulting error may be bounded above by the error found from the best approximation in this subspace. We provide numerical experiments which compare the error incurred by the ensemble Kalman method for inverse problems with the error of the best approximation in A, and with variants on traditional least-squares approaches, restricted to the subspace A. In so doing we demonstrate that the ensemble Kalman method for inverse problems provides a derivative-free optimization method with comparable accuracy to that achieved by traditional least-squares approaches. Furthermore, we also demonstrate that the accuracy is of the same order of magnitude as that achieved by the best approximation. Three examples are used to demonstrate these assertions: inversion of a compact linear operator; inversion of piezometric head to determine hydraulic conductivity in a Darcy model of groundwater flow; and inversion of Eulerian velocity measurements at positive times to determine the initial condition in an incompressible fluid. (paper)

  15. Cannabis Use and Drug Related Problems Among Adolescents in 27 European Countries: The Utility of the Prevention Paradox

    Directory of Open Access Journals (Sweden)

    Romelsjö Anders

    2014-10-01

    Full Text Available AIMS – To study the prevalence of cannabis use and drug-related problems among European adolescents and the utility of the prevention paradox. METHODS – Survey data from the European School Survey Project on Alcohol and Other Drugs (ESPAD in 2007 in the 27 countries with information about drug use and drug-related problems was used. We analysed the proportion of all drug-related problems that occurred in a high risk group and among others who had used cannabis in the previous 12 months. The cut-off for the high risk group was chosen to include 10-15 % of the most frequent cannabis users. RESULTS – The high risk groups accounted for a substantial, but a minority, of drug-related problems among boys as well as girls. A minority of those who had used cannabis reported any drug-related problem. The proportion of adolescents with drug-related problems and the average number of problems increased with frequency of cannabis use. CONCLUSIONS – We find support for policy measures of more general character, supported by the prevention paradox. However, this does not exclude a policy supporting frequent drug users if they can be identified

  16. Numerical methods and analysis of multiscale problems

    CERN Document Server

    Madureira, Alexandre L

    2017-01-01

    This book is about numerical modeling of multiscale problems, and introduces several asymptotic analysis and numerical techniques which are necessary for a proper approximation of equations that depend on different physical scales. Aimed at advanced undergraduate and graduate students in mathematics, engineering and physics – or researchers seeking a no-nonsense approach –, it discusses examples in their simplest possible settings, removing mathematical hurdles that might hinder a clear understanding of the methods. The problems considered are given by singular perturbed reaction advection diffusion equations in one and two-dimensional domains, partial differential equations in domains with rough boundaries, and equations with oscillatory coefficients. This work shows how asymptotic analysis can be used to develop and analyze models and numerical methods that are robust and work well for a wide range of parameters.

  17. Numerical Methods for Free Boundary Problems

    CERN Document Server

    1991-01-01

    About 80 participants from 16 countries attended the Conference on Numerical Methods for Free Boundary Problems, held at the University of Jyviiskylii, Finland, July 23-27, 1990. The main purpose of this conference was to provide up-to-date information on important directions of research in the field of free boundary problems and their numerical solutions. The contributions contained in this volume cover the lectures given in the conference. The invited lectures were given by H.W. Alt, V. Barbu, K-H. Hoffmann, H. Mittelmann and V. Rivkind. In his lecture H.W. Alt considered a mathematical model and existence theory for non-isothermal phase separations in binary systems. The lecture of V. Barbu was on the approximate solvability of the inverse one phase Stefan problem. K-H. Hoff­ mann gave an up-to-date survey of several directions in free boundary problems and listed several applications, but the material of his lecture is not included in this proceedings. H.D. Mittelmann handled the stability of thermo capi...

  18. Inhalation Exposure Method for Illegal Drugs.

    Science.gov (United States)

    Inomata, Akiko; Ogata, Akio; Tada, Yukie; Nagasawa, Akemichi; Yuzawa, Katsuhiro; Ando, Hiroshi; Kubo, Yoshikazu; Takahashi, Hiroshi; Kaihoko, Fujifumi; Tanaka, Kazuyoshi; Nakajima, Jun'ichi; Suzuki, Atsuko; Uemura, Nozomi; Moriyasu, Takako; Watanabe, Daisuke; Ishihara, Kei; Usami, Takashi; Kamei, Satoru; Kohno, Yasuaki

    2017-01-01

    We developed a new inhalation exposure method to evaluate effects of synthetic cannabimimetics that are being distributed as new, unregulated drugs in the Tokyo area. We selected the commercial product "SOUTOU" containing AB-CHMINACA and 5F-AMB as the test drug and dried marshmallow (Althaea officinalis) leaves as the negative control. A half cigarette packed with dried marshmallow leaves or SOUTOU was ignited, then mainstream smoke from each was delivered to five mice in an exposure box. After the cigarettes were fully consumed, neurobehavioral observations and a catalepsy test were performed at 15, 30 and 60 min after exposure. The effluent air from the exposure box was poured into impingers containing acetonitrile (first impinger) and dimethyl sulfoxide (second impinger). The resulting solutions were analyzed to assess decomposition of the synthetic cannabimimetics. Mice exposed to SOUTOU smoke showed many excitement behaviors and some suppressive behaviors at 15, 30 and 60 min. These clearly included cannabimimetic specific pharmacological actions. Negative control mice also showed some suppressive behaviors at 15 min but these were attenuated at later times, nearly disappearing at 60 min. In addition, the behavioral effects observed in controls were less pronounced than those in SOUTOU exposed mice. The inhalation exposure method developed in our study would be effective for determining cannabinoid specific pharmacological effects of illegal drugs, as well as for assessing the presence of active compound(s) by comparing the test substance with a negative control.

  19. The analysis of Drug - Related Problems in patients with gastroesophageal reflux disease treated with proton-pump inhibitors

    Directory of Open Access Journals (Sweden)

    Milutinović Jelena D.

    2015-01-01

    Full Text Available Introduction: Drug-related problems are frequent in almost all therapeutic areas. Aims: The aim of this paper was to detect drug - related problems in patients with gastroesophageal reflux and to analyze their possible association with the patient characteristics. Material and methods: The study was designed as descriptive, retrospective, crosssectional study aiming to determine the most common drug - related problems in patients with gastro-esophageal reflux disease treated with proton-pump inhibitors. The survey was conducted at the Department of Gastroenterology, Clinical Centre in Kragujevac. The study enrolled all patients treated from gastroesophageal reflux disease with proton pump inhibitors during the time period from 1.1.2014 until 1.1.2015. The study used descriptive statistics (percentage distribution, mean and standard deviation. The correlation between the number of adverse events and patient characteristics was also calculated. Results: The average age of the patients was 55.97±15.811 years, and 43 of the patients (60.6 % were male. The average hospitalization duration was 12.30±8.89 days. Based on the Pharmaceutical Care Network Europe classification, there were 182 Drug-Related Problems which was, on average, 2.56 problems per patient. Only 5 patients (7% did not report any problem while 11 patients (15.49% had over 10 possible drug-drug interactions. The most common problems which occurred were erroneous drug choice, inappropriate administration and possible interactions between medications. Conclusions: Based on the results of this study, one must pay attention to possible drug interactions and other problems which may occur with proton-pump inhibitors. Recognition of different sub-types of drug-related problems and of factors associated with drug related problems may reduce risk from adverse outcomes of gastro-esophageal reflux disease treatment with proton pump inhibitors.

  20. [Effects of the new comprehensive system for designating illegal drug components on the abuse of designer drugs and future problems based on an online questionnaire].

    Science.gov (United States)

    Morino, Taichi; Okazaki, Mitsuhiro; Toda, Takaki; Yokoyama, Takashi

    2015-12-01

    Recently, the abuse of designer drugs has become a social problem. Designer drugs are created by modifying part of the chemical structure of drugs that have already been categorized as illegal, thereby creating a different chemical compound in order to evade Pharmaceutical Affairs Law regulations. The new comprehensive system for designating illegal drug components has been in effect since March 2013, and many designer drugs can now be regulated. We conducted an online questionnaire survey of people with a history of designer drug use to elucidate the effects of the new system on the abuse of designer drugs and to identify potential future problems. Over half the subjects obtained designer drugs only before the new system was implemented. Awareness of the system was significantly lower among subjects who obtained designer drugs for the first time after its introduction than those who obtained the drugs only before its implementation. Due to the new system, all methods of acquiring designer drugs saw decreases in activity. However, the ratio of the acquisition of designer drugs via the Internet increased. Since over 50% of the subjects never obtained designer drugs after the new system was introduced, goals that aimed to make drug procurement more difficult were achieved. However, awareness of the new system among subjects who obtained designer drugs after the new system was introduced was significantly low. Therefore, fostering greater public awareness of the new system is necessary. The results of the questionnaire also suggested that acquiring designer drugs through the Internet has hardly been affected by the new system. We strongly hope that there will be a greater push to restrict the sale of designer drugs on the Internet in the near future.

  1. A split operator method for transient problems

    International Nuclear Information System (INIS)

    Belytschko, T.B.

    1983-01-01

    Numerous techniques have been developed for improving the computational efficiency of transient analysis: mesh partitioning, subcycling procedures and operator splitting methods. In mesh partitioning methods, the model is divided into subdomains which are integrated by different time integrators, typically implicit and explicit. Any stiff portions of the model are integrated by the implicit operator so that the size of the time step can be increased. In subcycling procedures, the stiff portions are integrated by smaller time steps, yielding similar benefits. However, in models for which the governing partial differential equations are basically of a parabolic character, explicit methods can become quite expensive for refined models because the size of the stable time step decreases with the square of the minimum element dimension. Thus explicit methods, whether employed alone or with partitioning or subcycling, have inherent limitations in these problems. A new procedure is here described for the element-by-element semi-implicit method of Hughes and coworkers which requires the solution of only small systems of equations. This procedure is described for a family of uniform gradient or strain elements which are widely used in nonlinear transient analysis. The diffusion equation and the equations of motion for both shells and continua have been treated, but only the former is considered herein. Results are presented for several examples which show the potential of this method for improving the efficiency of a large-scale linear and nonlinear computations. (orig./RW)

  2. Drug-Drug/Drug-Excipient Compatibility Studies on Curcumin using Non-Thermal Methods

    Directory of Open Access Journals (Sweden)

    Moorthi Chidambaram

    2014-05-01

    Full Text Available Purpose: Curcumin is a hydrophobic polyphenol isolated from dried rhizome of turmeric. Clinical usefulness of curcumin in the treatment of cancer is limited due to poor aqueous solubility, hydrolytic degradation, metabolism, and poor oral bioavailability. To overcome these limitations, we proposed to fabricate curcumin-piperine, curcumin-quercetin and curcumin-silibinin loaded polymeric nanoformulation. However, unfavourable combinations of drug-drug and drug-excipient may result in interaction and rises the safety concern. Hence, the present study was aimed to assess the interaction of curcumin with excipients used in nanoformulations. Methods: Isothermal stress testing method was used to assess the compatibility of drug-drug/drug-excipient. Results: The combination of curcumin-piperine, curcumin-quercetin, curcumin-silibinin and the combination of other excipients with curcumin, piperine, quercetin and silibinin have not shown any significant physical and chemical instability. Conclusion: The study concludes that the curcumin, piperine, quercetin and silibinin is compatible with each other and with other excipients.

  3. Sewerage systems: Overflow problems and renovation methods

    Energy Technology Data Exchange (ETDEWEB)

    Tanttu, Unto [Plancenter Ltd. (Finland)

    1987-12-15

    Total investments in Finland (1984) spent on sewer systems were roughly FIM 590 million. A big share, about 14 % of this sum (FIM 82 million), was spent on rehabilitation of networks. But is this still enough? According to some evaluations the respective amount should be about FIM 500 million for rehabilitation only. So the question, how to keep the performance of sewer networks satisfactory in the future, is really important. The overflow problem is one of the most serious problems caused by old and improperly working sewer systems. Anyhow, several other aspects of a poor condition of sewers are to be seen: - excess hydraulic loading of treatment plants, - normal maintenance and operation (flushing, opening of clogs) increases, and is more expensive, - unexpected renovation works and interruptions in operation cause e.g. troubles in traffic, odour problems in the environment, hygienic hazards etc., - the performance of other underground networks (water pipes, district heating pipes etc.) may be threatened by earth crushings due to old sewers. In this paper a short description of these items is presented as well as a description of the sewer renovation methods used recently in Finland.

  4. College Students' Perceptions of Severity and Willingness to Seek Psychological Help For Drug and Alcohol Problems

    Science.gov (United States)

    Lowinger, Robert Jay

    2012-01-01

    A sample of 201 college students were surveyed with respect to their perceptions of severity and willingness to seek psychological help for drug and alcohol problems. Results indicated that students perceive alcohol problems as significantly less serious than drug problems and are significantly less willing to seek help for alcohol problems. Males…

  5. Hybrid intelligent optimization methods for engineering problems

    Science.gov (United States)

    Pehlivanoglu, Yasin Volkan

    The purpose of optimization is to obtain the best solution under certain conditions. There are numerous optimization methods because different problems need different solution methodologies; therefore, it is difficult to construct patterns. Also mathematical modeling of a natural phenomenon is almost based on differentials. Differential equations are constructed with relative increments among the factors related to yield. Therefore, the gradients of these increments are essential to search the yield space. However, the landscape of yield is not a simple one and mostly multi-modal. Another issue is differentiability. Engineering design problems are usually nonlinear and they sometimes exhibit discontinuous derivatives for the objective and constraint functions. Due to these difficulties, non-gradient-based algorithms have become more popular in recent decades. Genetic algorithms (GA) and particle swarm optimization (PSO) algorithms are popular, non-gradient based algorithms. Both are population-based search algorithms and have multiple points for initiation. A significant difference from a gradient-based method is the nature of the search methodologies. For example, randomness is essential for the search in GA or PSO. Hence, they are also called stochastic optimization methods. These algorithms are simple, robust, and have high fidelity. However, they suffer from similar defects, such as, premature convergence, less accuracy, or large computational time. The premature convergence is sometimes inevitable due to the lack of diversity. As the generations of particles or individuals in the population evolve, they may lose their diversity and become similar to each other. To overcome this issue, we studied the diversity concept in GA and PSO algorithms. Diversity is essential for a healthy search, and mutations are the basic operators to provide the necessary variety within a population. After having a close scrutiny of the diversity concept based on qualification and

  6. Faces of Change: Do I Have a Problem with Alcohol or Drugs?

    Science.gov (United States)

    ... You Do About Drugs And Alcohol In Your Life? Know if there’s a problem: • Are drugs or alcohol affecting your work or health? • Do you feel like you need alcohol or drugs to get through the day? • Are your friends or family members telling you there’s a problem? ...

  7. Numerical Methods for Bayesian Inverse Problems

    KAUST Repository

    Ernst, Oliver

    2014-01-06

    We present recent results on Bayesian inversion for a groundwater flow problem with an uncertain conductivity field. In particular, we show how direct and indirect measurements can be used to obtain a stochastic model for the unknown. The main tool here is Bayes’ theorem which merges the indirect data with the stochastic prior model for the conductivity field obtained by the direct measurements. Further, we demonstrate how the resulting posterior distribution of the quantity of interest, in this case travel times of radionuclide contaminants, can be obtained by Markov Chain Monte Carlo (MCMC) simulations. Moreover, we investigate new, promising MCMC methods which exploit geometrical features of the posterior and which are suited to infinite dimensions.

  8. Numerical Methods for Bayesian Inverse Problems

    KAUST Repository

    Ernst, Oliver; Sprungk, Bjorn; Cliffe, K. Andrew; Starkloff, Hans-Jorg

    2014-01-01

    We present recent results on Bayesian inversion for a groundwater flow problem with an uncertain conductivity field. In particular, we show how direct and indirect measurements can be used to obtain a stochastic model for the unknown. The main tool here is Bayes’ theorem which merges the indirect data with the stochastic prior model for the conductivity field obtained by the direct measurements. Further, we demonstrate how the resulting posterior distribution of the quantity of interest, in this case travel times of radionuclide contaminants, can be obtained by Markov Chain Monte Carlo (MCMC) simulations. Moreover, we investigate new, promising MCMC methods which exploit geometrical features of the posterior and which are suited to infinite dimensions.

  9. Open source biotechnology : A drug for developing countries' health problems?

    NARCIS (Netherlands)

    Schellekens, M.H.M.

    2008-01-01

    In developing countries, many people suffer from diseases for which there are no drugs or for which drugs exist that they cannot afford because they are too expensive. The advent of genomics has sparked the idea that new drugs can be more easily developed and that genomics thus could lessen the

  10. Optimization methods for activities selection problems

    Science.gov (United States)

    Mahad, Nor Faradilah; Alias, Suriana; Yaakop, Siti Zulaika; Arshad, Norul Amanina Mohd; Mazni, Elis Sofia

    2017-08-01

    Co-curriculum activities must be joined by every student in Malaysia and these activities bring a lot of benefits to the students. By joining these activities, the students can learn about the time management and they can developing many useful skills. This project focuses on the selection of co-curriculum activities in secondary school using the optimization methods which are the Analytic Hierarchy Process (AHP) and Zero-One Goal Programming (ZOGP). A secondary school in Negeri Sembilan, Malaysia was chosen as a case study. A set of questionnaires were distributed randomly to calculate the weighted for each activity based on the 3 chosen criteria which are soft skills, interesting activities and performances. The weighted was calculated by using AHP and the results showed that the most important criteria is soft skills. Then, the ZOGP model will be analyzed by using LINGO Software version 15.0. There are two priorities to be considered. The first priority which is to minimize the budget for the activities is achieved since the total budget can be reduced by RM233.00. Therefore, the total budget to implement the selected activities is RM11,195.00. The second priority which is to select the co-curriculum activities is also achieved. The results showed that 9 out of 15 activities were selected. Thus, it can concluded that AHP and ZOGP approach can be used as the optimization methods for activities selection problem.

  11. Prevalence of drug-related problems in self-medication in Danish community pharmacies

    Directory of Open Access Journals (Sweden)

    Bente Frøkjær

    2012-01-01

    Full Text Available Background: Drug-related problems are known to be a major problem associated with pharmacotherapy. A broad range of studies, mainly in the area of prescription-only medicines, supports this fact. Only a few studies have evaluated drug-related problems with over-the-counter medicine and the role of community pharmacies in this. Purpose: To quantify drug-related problems in self-medication (use of over-the-counter medicine identified by community pharmacies in Denmark and to document the interventions by pharmacy staff in relation to the identified drug-related problems. Method: A descriptive study mapping drug-related problems in self-medication registered at the counter at a selected number of Danish community pharmacies. Results: Data for 3,868 consecutive customers with requests for over-the-counter (OTC medicines were registered at 39 community pharmacies. The pharmacies registered a total number of 4,324 OTC medicines requests, illustrating that a customer requested 1.1 OTC medicines on average. Drug-related problems (DRPs were identified for 813 customers, equivalent to DRPs for 21.0 % of all customers, presenting symptoms or requesting OTC medicines, and for 20 % of all over-the-counter medicines requests. 1,239 DRPs were registered, corresponding to an average of 1.5 DRPs per customer requesting OTC medicines. Community pharmacies estimated that they solved or partly solved 76.2 % of the detected DRPs; 73 % were solved without involving a general practitioner. Conclusions: DRPs were identified for 21.0 % of the pharmacy customers presenting a symptom or asking for an OTC medicine. The community pharmacy counselled the customers with DRPs more thoroughly than other customers by giving 2.4 pieces of professional advice, compared to an average of 2.1 to customers in general. It is not possible to determine the magnitude of the safety risk involved. Based on the most frequent categories of DRPs, there were risks of insufficient effect

  12. Prevalence of drug-related problems in self-medication in Danish community pharmacies

    Directory of Open Access Journals (Sweden)

    Charlotte Rossing

    2012-01-01

    Full Text Available Background: Drug-related problems are known to be a major problem associated with pharmacotherapy. A broad range of studies, mainly in the area of prescription-only medicines, supports this fact. Only a few studies have evaluated drug-related problems with over-the-counter medicine and the role of community pharmacies in this.Purpose: To quantify drug-related problems in self-medication (use of over-the-counter medicine identified by community pharmacies in Denmark and to document the interventions by pharmacy staff in relation to the identified drug-related problems.Method: A descriptive study mapping drug-related problems in self-medication registered at the counter at a selected number of Danish community pharmacies.Results: Data for 3,868 consecutive customers with requests for over-the-counter (OTC medicines were registered at 39 community pharmacies. The pharmacies registered a total number of 4,324 OTC medicines requests, illustrating that a customer requested 1.1 OTC medicines on average. Drug-related problems (DRPs were identified for 813 customers, equivalent to DRPs for 21.0 % of all customers, presenting symptoms or requesting OTC medicines, and for 20 % of all over-the-counter medicines requests. 1,239 DRPs were registered, corresponding to an average of 1.5 DRPs per customer requesting OTC medicines.Community pharmacies estimated that they solved or partly solved 76.2 % of the detected DRPs; 73 % were solved without involving a general practitioner.Conclusions: DRPs were identified for 21.0 % of the pharmacy customers presenting a symptom or asking for an OTC medicine. The community pharmacy counselled the customers with DRPs more thoroughly than other customers by giving 2.4 pieces of professional advice, compared to an average of 2.1 to customers in general. It is not possible to determine the magnitude of the safety risk involved. Based on the most frequent categories of DRPs, there were risks of insufficient effect, unintended

  13. Differential Effects of Parent and Grandparent Drug Use on Behavior Problems of Male and Female Children.

    Science.gov (United States)

    Stein, Judith A.; And Others

    1993-01-01

    Grandparents' and mothers' drug use predicted hyperactivity, psychosomatic complaints, and social problems for boys, and acting-out behaviors for boys and girls. Maternal drug use predicted fearfulness, hyperactivity, and social problems for boys, and developmental problems for boys and girls. (BC)

  14. Identification and management of physical health problems among an injecting drug using population

    OpenAIRE

    Patton, Robert

    2013-01-01

    Injecting drug use is highly prevalent in London and is associated with specific physical health problems. These problems are related to the toxicity of the substances, their mode of consumption and as a consequence of the drug taking lifestyle. Hepatitis B and C viral infections are common among drug users due to sharing of both needles and other drug taking paraphernalia. Hepatitis B infection can be prevented by immunisation. Hepatitis C infection can interact with alcohol consumption to a...

  15. Variational methods for eigenvalue problems an introduction to the weinstein method of intermediate problems

    CERN Document Server

    Gould, S H

    1966-01-01

    The first edition of this book gave a systematic exposition of the Weinstein method of calculating lower bounds of eigenvalues by means of intermediate problems. This second edition presents new developments in the framework of the material contained in the first edition, which is retained in somewhat modified form.

  16. Drug-Target Interactions: Prediction Methods and Applications.

    Science.gov (United States)

    Anusuya, Shanmugam; Kesherwani, Manish; Priya, K Vishnu; Vimala, Antonydhason; Shanmugam, Gnanendra; Velmurugan, Devadasan; Gromiha, M Michael

    2018-01-01

    Identifying the interactions between drugs and target proteins is a key step in drug discovery. This not only aids to understand the disease mechanism, but also helps to identify unexpected therapeutic activity or adverse side effects of drugs. Hence, drug-target interaction prediction becomes an essential tool in the field of drug repurposing. The availability of heterogeneous biological data on known drug-target interactions enabled many researchers to develop various computational methods to decipher unknown drug-target interactions. This review provides an overview on these computational methods for predicting drug-target interactions along with available webservers and databases for drug-target interactions. Further, the applicability of drug-target interactions in various diseases for identifying lead compounds has been outlined. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Problem drug use the public health imperative: what some of the literature says.

    Science.gov (United States)

    Bevan, Gez

    2009-12-16

    With more than 200,000 problem drug users is contact with structured treatment services in England the public health imperative behind drug treatment is great. Problem drug use for many is a chronic and relapsing condition, where "cure" is often neither a reasonable or appropriate expectation and it can further be argued that in these circumstances problem drug use is no different from any number of chronic and enduring health conditions that are managed in the health care system and therefore should be conceptualised as such. A public health approach to drug treatment emphasises the need for drug users in or accessing treatment, to reduce their harmful drug use, reduce drug use related risks such as sepsis and overdose and stay alive for longer. However a public health perspective in relation to problem drug use isn't always either apparent or readily understood and to that end there is still a significant need to continue the arguments and debate that treatment and interventions for problem and dependent drug users need to extend beyond an individualistic approach. For the purposes of discussion in this article public and population health will be used interchangeably. A recognition and acceptance that a public and population health approach to the management of problem drug users is sound public health policy also then requires a long term commitment in terms of staffing and resources where service delivery mirrors that of chronic condition management.

  18. Drug Facilitated Sexual Assault and That the Problems in Turkey

    Directory of Open Access Journals (Sweden)

    Nabi Kantarcı

    2012-10-01

    Full Text Available The assailants of sexuel assault to serve this purpose to the victims of many different drug can use. These drugs can be applied together with alcohol, soft drinks, water and other drinks can be given together. Most of these drugs tasteless and odorless. In a few minutes after ingestion chemical effect of drugs can start. Victims the conscious reduction and limitation of the physical move occur. Drug drinking from the pass the time until impact memory loss can occur. For this purpose the main benzodiazepines (Diazepam, flunitrazepam, lorazepam, etc., hypnotics (Zopiclone, zolpidem, anesthetics (Gama-hydroxybutyrate, ketamine, amphetamines (Metylendioxymetamphetamine=ecstasy, opiats (Cocaine, cannabis=marihuana and alcohols such as ethanol substances used. However in study frequently encountered in the literature; cocaine, cannabis, metylendioxymetamphetamine, zolpidem, ketamine hydrochloride, zopiclone, gamma hydroxybutirate, diazepam, flunitrazepam and the effects of these substances after oral ingestion were evaluated and the approach to victims.

  19. Nonclassical pseudospectral method for the solution of brachistochrone problem

    International Nuclear Information System (INIS)

    Alipanah, A.; Razzaghi, M.; Dehghan, M.

    2007-01-01

    In this paper, nonclassical pseudospectral method is proposed for solving the classic brachistochrone problem. The brachistochrone problem is first formulated as a nonlinear optimal control problem. Properties of nonclassical pseudospectral method are presented, these properties are then utilized to reduce the computation of brachistochrone problem to the solution of algebraic equations. Using this method, the solution to the brachistochrone problem is compared with those in the literature

  20. Drug-related problems identified in medication reviews by Australian pharmacists

    DEFF Research Database (Denmark)

    Stafford, Andrew C; Tenni, Peter C; Peterson, Gregory M

    2009-01-01

    OBJECTIVE: In Australia, accredited pharmacists perform medication reviews for patients to identify and resolve drug-related problems. We analysed the drug-related problems identified in reviews for both home-dwelling and residential care-facility patients. The objective of this study was to exam......OBJECTIVE: In Australia, accredited pharmacists perform medication reviews for patients to identify and resolve drug-related problems. We analysed the drug-related problems identified in reviews for both home-dwelling and residential care-facility patients. The objective of this study....... These reviews had been self-selected by pharmacists and submitted as part of the reaccreditation process to the primary body responsible for accrediting Australian pharmacists to perform medication reviews. The drug-related problems identified in each review were classified by type and drugs involved. MAIN...... OUTCOME MEASURE: The number and nature of drug-related problems identified in pharmacist-conducted medication reviews. RESULTS: There were 1,038 drug-related problems identified in 234 medication reviews (mean 4.6 (+/-2.2) problems per review). The number of problems was higher (4.9 +/- 2.0 vs. 3.9 +/- 2...

  1. Drug-related problems and changes in drug utilization after medication reviews in nursing homes in Oslo, Norway.

    Science.gov (United States)

    Fog, Amura Francesca; Kvalvaag, Gunnar; Engedal, Knut; Straand, Jørund

    2017-12-01

    We describe the drug-related problems (DRPs) identified during medication reviews (MRs) and the changes in drug utilization after MRs at nursing homes in Oslo, Norway. We explored predictors for the observed changes. Observational before-after study. Forty-one nursing homes. MRs performed by multidisciplinary teams during November 2011 to February 2014. In all, 2465 long-term care patients. DRPs identified by explicit criteria (STOPP/START and NORGEP) and drug-drug interaction database; interventions to resolve DRPs; drug use changes after MR. A total of 6158 DRPs were identified, an average of 2.6 DRPs/patient, 2.0 for regular and 0.6 for pro re nata (prn) drugs. Of these patients, 17.3% had no DRPs. The remaining 82.7% of the patients had on average 3.0 DRPs/patient. Use of unnecessary drugs (43.5%), excess dosing (12.5%) and lack of monitoring of the drug use (11%) were the most frequent DRPs. Opioids and psychotropic drugs were involved in 34.4% of all DRPs. The mean number of drugs decreased after the MR from 6.8 to 6.3 for regular drugs and from 3.0 to 2.6 for prn drugs. Patients with DRPs experienced a decrease of 1.1 drugs after MR (0.5 for regular and 0.6 for prn drugs). The reduction was most pronounced for the regular use of antipsychotics, antidepressants, hypnotics/sedatives, diuretics, antithrombotic agents, antacid drugs; and for prn use of anxiolytics, opioids, hypnotics/sedatives, metoclopramide and NSAIDs. The medication review resulted in less drug use, especially opioids and psychotropic drugs.

  2. Program Administrator's Handbook. Strategies for Preventing Alcohol and Other Drug Problems. The College Series.

    Science.gov (United States)

    CSR, Inc., Washington, DC.

    This handbook is for administrators of programs in higher education settings which deal with alcohol and other drug (AOD) related problems. Chapter 1, "Defining the Problem, Issues, and Trends" examines the problem from various perspectives and presents the latest statistics on the extent of AOD use on campuses, specific problems affecting…

  3. Numerical methods for hydrodynamic stability problems

    International Nuclear Information System (INIS)

    Fujimura, Kaoru

    1985-11-01

    Numerical methods for solving the Orr-Sommerfeld equation, which is the fundamental equation of the hydrodynamic stability theory for various shear flows, are reviewed and typical numerical results are presented. The methods of asymptotic solution, finite difference methods, initial value methods and expansions in orthogonal functions are compared. (author)

  4. Multifield methods for nuclear thermohydraulics problems

    International Nuclear Information System (INIS)

    Banerjee, S.

    1987-01-01

    The multifield model, in which separate sets of conservation equations are written for each phase, or clearly identifiable portions of a phase, is derived by averaging the local instantaneous equations. The closure relationships required to replace information lost in the averaging process are discussed. The mathematical structure of the model is considered and it is shown that application to a variety of problems in which the phases are well separated leads to good predictions of experimental data. For problems in which the phases are more closely coupled, the model is more difficult to apply correctly. However, careful consideration of interfield momentum and heat transfer is shown to give excellent results for some complex problems like density wave propagation in bubbly flows. The model in its present form is shown to be less useful for highly intermittent regimes like slug and churn flows. Data on a reflux condensation situation near the flooding point are discussed to indicate directions in which further work is required

  5. Quasihomogeneous function method and Fock's problem

    International Nuclear Information System (INIS)

    Smyshlyaev, V.P.

    1987-01-01

    The diffraction of a high-frequency wave by a smooth convex body near the tangency point of the limiting ray to the surface is restated as the scattering problem for the Schrodinger equation with a linear potential on a half-axis. Various prior estimates for the scattering problem are used in order to prove existence, uniqueness, and smoothness theorems. The corresponding solution satisfies the principle of limiting absorption. The formal solution of the corresponding Schrodinger equation in the form of quasihomogeneous functions is essentially used in their constructions

  6. Methods of intermediate problems for eigenvalues

    CERN Document Server

    Weinstein, Alexander

    1972-01-01

    In this book, we study theoretical and practical aspects of computing methods for mathematical modelling of nonlinear systems. A number of computing techniques are considered, such as methods of operator approximation with any given accuracy; operator interpolation techniques including a non-Lagrange interpolation; methods of system representation subject to constraints associated with concepts of causality, memory and stationarity; methods of system representation with an accuracy that is the best within a given class of models; methods of covariance matrix estimation;methods for low-rank mat

  7. Initial value methods for boundary value problems

    CERN Document Server

    Meyer, Gunter H

    1973-01-01

    In this book, we study theoretical and practical aspects of computing methods for mathematical modelling of nonlinear systems. A number of computing techniques are considered, such as methods of operator approximation with any given accuracy; operator interpolation techniques including a non-Lagrange interpolation; methods of system representation subject to constraints associated with concepts of causality, memory and stationarity; methods of system representation with an accuracy that is the best within a given class of models; methods of covariance matrix estimation;methods for low-rank mat

  8. Problems of method of technology assessment

    International Nuclear Information System (INIS)

    Zimmermann, V.

    1993-03-01

    The study undertakes to analyse the theoretical and methodological structure of Technology Assessment (TA). It is based on a survey of TA studies which provided an important condition for theoreticall sound statements on methodological aspects of TA. It was established that the main basic theoretical problems of TA are in the field of dealing with complexity. This is also apparent in the constitution of problems, the most elementary and central approach of TA. Scientifically founded constitution of problems and the corresponding construction of models call for interdisciplinary scientific work. Interdisciplinarity in the TA research process is achieved at the level of virtual networks, these networks being composed of individuals suited to teamwork. The emerging network structures have an objective-organizational and an ideational basis. The objective-organizational basis is mainly the result of team composition and the external affiliations of the team members. The ideational basis of the virtual network is represented by the team members' mode of thinking, which is individually located at a multidisciplinary level. The theoretical 'skeleton' of the TA knowledge system, which is represented by process knowledge based linkage structures, can be generated and also processed in connection with the knowledge on types of problems, areas of analysis and procedures to deal with complexity. Within this process, disciplinary knowledge is a necessary but not a sufficient condition. Metatheoretical and metadisciplinary knowledge and the correspondingly processes complexity of models are the basis for the necessary methodological awareness, that allows TA to become designable as a research procedure. (orig./HP) [de

  9. Numerical methods for coupled fracture problems

    Science.gov (United States)

    Viesca, Robert C.; Garagash, Dmitry I.

    2018-04-01

    We consider numerical solutions in which the linear elastic response to an opening- or sliding-mode fracture couples with one or more processes. Classic examples of such problems include traction-free cracks leading to stress singularities or cracks with cohesive-zone strength requirements leading to non-singular stress distributions. These classical problems have characteristic square-root asymptotic behavior for stress, relative displacement, or their derivatives. Prior work has shown that such asymptotics lead to a natural quadrature of the singular integrals at roots of Chebyhsev polynomials of the first, second, third, or fourth kind. We show that such quadratures lead to convenient techniques for interpolation, differentiation, and integration, with the potential for spectral accuracy. We further show that these techniques, with slight amendment, may continue to be used for non-classical problems which lack the classical asymptotic behavior. We consider solutions to example problems of both the classical and non-classical variety (e.g., fluid-driven opening-mode fracture and fault shear rupture driven by thermal weakening), with comparisons to analytical solutions or asymptotes, where available.

  10. Monte Carlo method for neutron transport problems

    International Nuclear Information System (INIS)

    Asaoka, Takumi

    1977-01-01

    Some methods for decreasing variances in Monte Carlo neutron transport calculations are presented together with the results of sample calculations. A general purpose neutron transport Monte Carlo code ''MORSE'' was used for the purpose. The first method discussed in this report is the method of statistical estimation. As an example of this method, the application of the coarse-mesh rebalance acceleration method to the criticality calculation of a cylindrical fast reactor is presented. Effective multiplication factor and its standard deviation are presented as a function of the number of histories and comparisons are made between the coarse-mesh rebalance method and the standard method. Five-group neutron fluxes at core center are also compared with the result of S4 calculation. The second method is the method of correlated sampling. This method was applied to the perturbation calculation of control rod worths in a fast critical assembly (FCA-V-3) Two methods of sampling (similar flight paths and identical flight paths) are tested and compared with experimental results. For every cases the experimental value lies within the standard deviation of the Monte Carlo calculations. The third method is the importance sampling. In this report a biased selection of particle flight directions discussed. This method was applied to the flux calculation in a spherical fast neutron system surrounded by a 10.16 cm iron reflector. Result-direction biasing, path-length stretching, and no biasing are compared with S8 calculation. (Aoki, K.)

  11. METHOD FOR SOLVING FUZZY ASSIGNMENT PROBLEM USING MAGNITUDE RANKING TECHNIQUE

    OpenAIRE

    D. Selvi; R. Queen Mary; G. Velammal

    2017-01-01

    Assignment problems have various applications in the real world because of their wide applicability in industry, commerce, management science, etc. Traditional classical assignment problems cannot be successfully used for real life problem, hence the use of fuzzy assignment problems is more appropriate. In this paper, the fuzzy assignment problem is formulated to crisp assignment problem using Magnitude Ranking technique and Hungarian method has been applied to find an optimal solution. The N...

  12. Admissions for drug-related problems at the Emergency Department of a University Hospital in the Kingdom of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mastour S Alghamdy

    2015-01-01

    Full Text Available Background and Aim: Medication Errors can result in drug-related problems (DRPs. Insight into the frequency, type, and severity of DRPs could help reduce their incidence. The aim of the present study was to estimate the prevalence of admissions as a result of DRPs at the Emergency Department (ED of a university hospital in the Kingdom of Saudi Arabia. Materials and Methods: Files of suspected cases of DRPs reporting to ED in the year 2012 were scrutinized. Suspicion arose from the hospital record system based on Diagnosis Code Numbers (ICD-9-CM, Professional 2010 and from triggers, such as some drugs, laboratory tests, and signs and symptoms pointing to DRPs. Results: Of 5574 admissions, 253 (4.5% were DRPs and were categorized as: Overdose toxicity and side effects of drugs 50 (19.8%, drug-interactions 29 (11.5%, accidental and suicidal drug ingestions 26 (10.3%, drug abuse 18 (7.1%, drug allergy 10 (4%, super-infections 8 (3.2%, and noncompliance to treatment 112 (44.3%. About 70% of DRPs were preventable; 67 (26.5% required hospital admission for 7-102 days and 10 (4% died. Conclusions: Noncompliance to treatment, overdose toxicity, drug interactions, and drug abuse are important causes of hospital admissions as a result of DRPs. Awareness of prescribers to the problem and their education would help to prevent them and improve patient care.

  13. Characterization of drug-related problems identified by clinical pharmacy staff at Danish hospitals

    DEFF Research Database (Denmark)

    Kjeldsen, Lene Juel; Birkholm, Trine; Fischer, Hanne

    2014-01-01

    Background In 2010, a database of drug related problems (DRPs) was implemented to assist clinical pharmacy staff in documenting clinical pharmacy activities locally. A study of quality, reliability and generalisability showed that national analyses of the data could be conducted. Analyses...... at the national level may help identify and prevent DRPs by performing national interventions. Objective The aim of the study was to explore the DRP characteristics as documented by clinical pharmacy staff at hospital pharmacies in the Danish DRP-database during a 3-year period. Setting Danish hospital pharmacies....... Method Data documented in the DRP-database during the initial 3 years after implementation were analyzed retrospectively. The DRP-database contains DRPs reported at hospitals by clinical pharmacy staff. The analyses focused on DRP categories, implementation rates and drugs associated with the DRPs. Main...

  14. Preconditioned Krylov subspace methods for eigenvalue problems

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Kesheng; Saad, Y.; Stathopoulos, A. [Univ. of Minnesota, Minneapolis, MN (United States)

    1996-12-31

    Lanczos algorithm is a commonly used method for finding a few extreme eigenvalues of symmetric matrices. It is effective if the wanted eigenvalues have large relative separations. If separations are small, several alternatives are often used, including the shift-invert Lanczos method, the preconditioned Lanczos method, and Davidson method. The shift-invert Lanczos method requires direct factorization of the matrix, which is often impractical if the matrix is large. In these cases preconditioned schemes are preferred. Many applications require solution of hundreds or thousands of eigenvalues of large sparse matrices, which pose serious challenges for both iterative eigenvalue solver and preconditioner. In this paper we will explore several preconditioned eigenvalue solvers and identify the ones suited for finding large number of eigenvalues. Methods discussed in this paper make up the core of a preconditioned eigenvalue toolkit under construction.

  15. Iterative algorithm for the volume integral method for magnetostatics problems

    International Nuclear Information System (INIS)

    Pasciak, J.E.

    1980-11-01

    Volume integral methods for solving nonlinear magnetostatics problems are considered in this paper. The integral method is discretized by a Galerkin technique. Estimates are given which show that the linearized problems are well conditioned and hence easily solved using iterative techniques. Comparisons of iterative algorithms with the elimination method of GFUN3D shows that the iterative method gives an order of magnitude improvement in computational time as well as memory requirements for large problems. Computational experiments for a test problem as well as a double layer dipole magnet are given. Error estimates for the linearized problem are also derived

  16. Drug-related problems among community-dwelling older adults in mainland China.

    Science.gov (United States)

    Yang, Jiadan; Meng, Long; Liu, Yu; Lv, Liping; Sun, Shusen; Long, Rui; Shan, Xuefeng; Song, Jie; Qiu, Feng

    2018-04-01

    Background Little is known about the extent of drug-related problems (DRPs) in community-dwelling older adult patients with chronic diseases in mainland China. Setting A medication therapy review service at a community health center in Chongqing, China. Objective To identify and categorize DRPs along with pharmacists' recommendations in addressing the DRPs identified. Method The study was conducted between May 2015 and July 2016. A total of 102 community-dwelling older adults were included. MTR was carried out by clinical pharmacists. DRPs and pharmacotherapy recommendations were recorded and analyzed. Main outcome measure The number of drug-related problems and main problem categories. Results The average age of patients was 69.4 years. Patients took an average of 6.3 medications. A total of 489 DRPs were identified (mean of 4.8 per patient). The most common category was under-treated (27.8%) followed by over- or under-dose (18.8%) and monitoring (17.8%). The number of medications taken was the significant associated factor for DRPs. Pharmacists made 526 recommendations to address the DRPs (mean of 1.1 recommendations per DRP). Primary care providers accepted 68.1% of these recommendations, and implemented 60.9% of them. Conclusion The prevalence of DRPs among studied patient population was high. Pharmacists may play a vital role in addressing the DRPs and optimize pharmacotherapy through MTR service located in community health centers.

  17. Heterogeneous Costs of Alcohol and Drug Problems Across Cities and Counties in California

    Science.gov (United States)

    Miller, Ted R.; Nygaard, Peter; Gaidus, Andrew; Grube, Joel W.; Ponicki, William R.; Lawrence, Bruce A.; Gruenewald, Paul J.

    2017-01-01

    Background Estimates of economic and social costs related to alcohol and other drug (AOD) use and abuse are usually made at state and national levels. Ecological analyses demonstrate, however, that substantial variations exist in the incidence and prevalence of AOD use and problems including impaired driving, violence, and chronic disease between smaller geopolitical units like counties and cities. This study examines the ranges of these costs across counties and cities in California. Methods We used estimates of the incidence and prevalence of AOD use, abuse and related problems to calculate costs in 2010 dollars for all 58 counties and an ecological sample of 50 cities with populations between 50,000 and 500,000 persons in California. The estimates were built from archival and public-use survey data collected at state, county and city-levels over the years from 2009 to 2010. Results Costs related to alcohol use and related problems exceeded those related to illegal drugs across all counties and most cities in the study. Substantial heterogeneities in costs were observed between cities within counties. Conclusions AOD costs are heterogeneously distributed across counties and cities, reflecting the degree to which different populations are engaged in use and abuse across the state. These findings provide a strong argument for the distribution of treatment and prevention resources proportional to need. PMID:28208210

  18. [Between scientific management and research-action: the problem of overconsumption of drugs in Kasongo (Zaire)].

    Science.gov (United States)

    De Brouwere, V; Van Lerberghe, W; Criel, B; Van Dormael, M

    1996-01-01

    A Primary Health Care (PHC) system may be effective and efficient to the extent that essential drugs are available in health services and financially accessible to the population. In developing countries, besides the difficulties related to supplying health services with adequate amounts of drugs, the control of drug consumption is one of the frequent problems encountered by health authorities. Literature is relatively abundant in the field of rationalization of the diagnosis and drug prescription processes, and also in the field of drug financing mechanisms; publications are however rather scarce when topics related to corruption or drug misappropriation are concerned. The case study submitted hereafter reports a drug overconsumption problem in the health centres (HC) of the Kasongo district (Zaire). Despite the existence of direct control mechanisms as well as indirect ones (monitoring of drug consumption by HC), the problem has been identified belatedly. The district staff then used a step-by-step analysis of the HC drug consumption profiles; this analysis allowed to demonstrate that misappropriation would be the most plausible hypothesis. In order to solve the misappropriation problem-the consequences of which jeopardized the functioning of the very health system-the district staff chose to involve the nurses, in charge of the HC, in the entire problem-solving process. This participative approach, involving different actors as partners, allowed to deepen the situation analysis and to elaborate solutions congruent with PHC principles and acceptable to all concerned.

  19. [Analysis of drug-related problems in a tertiary university hospital in Barcelona (Spain)].

    Science.gov (United States)

    Ferrández, Olivia; Casañ, Borja; Grau, Santiago; Louro, Javier; Salas, Esther; Castells, Xavier; Sala, Maria

    2018-05-07

    To describe drug-related problems identified in hospitalized patients and to assess physicians' acceptance rate of pharmacists' recommendations. Retrospective observational study that included all drug-related problems detected in hospitalized patients during 2014-2015. Statistical analysis included a descriptive analysis of the data and a multivariate logistic regression to evaluate the association between pharmacists' recommendation acceptance rate and the variable of interest. During the study period 4587 drug-related problems were identified in 44,870 hospitalized patients. Main drug-related problems were prescription errors due to incorrect use of the computerized physician order entry (18.1%), inappropriate drug-drug combination (13.3%) and dose adjustment by renal and/or hepatic function (11.5%). Acceptance rate of pharmacist therapy advice in evaluable cases was 81.0%. Medical versus surgical admitting department, specific types of intervention (addition of a new drug, drug discontinuation and correction of a prescription error) and oral communication of the recommendation were associated with a higher acceptance rate. The results of this study allow areas to be identified on which to implement optimization strategies. These include training courses for physicians on the computerized physician order entry, on drugs that need dose adjustment with renal impairment, and on relevant drug interactions. Copyright © 2018 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Application of collocation meshless method to eigenvalue problem

    International Nuclear Information System (INIS)

    Saitoh, Ayumu; Matsui, Nobuyuki; Itoh, Taku; Kamitani, Atsushi; Nakamura, Hiroaki

    2012-01-01

    The numerical method for solving the nonlinear eigenvalue problem has been developed by using the collocation Element-Free Galerkin Method (EFGM) and its performance has been numerically investigated. The results of computations show that the approximate solution of the nonlinear eigenvalue problem can be obtained stably by using the developed method. Therefore, it can be concluded that the developed method is useful for solving the nonlinear eigenvalue problem. (author)

  1. A Method for Solving Combinatoral Optimization Problems

    National Research Council Canada - National Science Library

    Ruffa, Anthony A

    2008-01-01

    .... The method discloses that when the boundaries create zones with boundary vertices confined to the adjacent zones, the sets of candidate HPs are found by advancing one zone at a time, considering...

  2. Galerkin finite element methods for wave problems

    Indian Academy of Sciences (India)

    basis functions (called G1FEM here) and quadratic basis functions (called G2FEM) ... mulation of Brookes & Hughes (1982) that implicitly incorporates numerical ..... functions and (c) SUPG method in the (kh − ω t)-plane for explicit Euler.

  3. Scattering theory methods for bound state problems

    International Nuclear Information System (INIS)

    Raphael, R.B.; Tobocman, W.

    1978-01-01

    For the analysis of the properties of a bound state system one may use in place of the Schroedinger equation the Lippmann-Schwinger (LS) equation for the wave function or the LS equation for the reactance operator. Use of the LS equation for the reactance operator constrains the solution to have correct asymptotic behaviour, so this approach would appear to be desirable when the bound state wave function is to be used to calculate particle transfer form factors. The Schroedinger equation based N-level analysis of the s-wave bound states of a square well is compared to the ones based on the LS equation. It is found that the LS equation methods work better than the Schroedinger equation method. The method that uses the LS equation for the wave function gives the best results for the wave functions while the method that uses the LS equation for the reactance operator gives the best results for the binding energies. The accuracy of the reactance operator based method is remarkably insensitive to changes in the oscillator constant used for the harmonic oscillator function basis set. It is also remarkably insensitive to the number of nodes in the bound state wave function. (Auth.)

  4. Pharmaceutical drug detailing in primary care: extent and methods

    DEFF Research Database (Denmark)

    Schramm, Jesper

    The dimension and methods of pharmaceutical marketing towards 47 danish general practitioners is described. Conclusions: Pharmaceutical drug detailing possesses a huge potential to influence the prescription pattern of GP's.......The dimension and methods of pharmaceutical marketing towards 47 danish general practitioners is described. Conclusions: Pharmaceutical drug detailing possesses a huge potential to influence the prescription pattern of GP's....

  5. Efficient decomposition and linearization methods for the stochastic transportation problem

    International Nuclear Information System (INIS)

    Holmberg, K.

    1993-01-01

    The stochastic transportation problem can be formulated as a convex transportation problem with nonlinear objective function and linear constraints. We compare several different methods based on decomposition techniques and linearization techniques for this problem, trying to find the most efficient method or combination of methods. We discuss and test a separable programming approach, the Frank-Wolfe method with and without modifications, the new technique of mean value cross decomposition and the more well known Lagrangian relaxation with subgradient optimization, as well as combinations of these approaches. Computational tests are presented, indicating that some new combination methods are quite efficient for large scale problems. (authors) (27 refs.)

  6. Toward solving the sign problem with path optimization method

    Science.gov (United States)

    Mori, Yuto; Kashiwa, Kouji; Ohnishi, Akira

    2017-12-01

    We propose a new approach to circumvent the sign problem in which the integration path is optimized to control the sign problem. We give a trial function specifying the integration path in the complex plane and tune it to optimize the cost function which represents the seriousness of the sign problem. We call it the path optimization method. In this method, we do not need to solve the gradient flow required in the Lefschetz-thimble method and then the construction of the integration-path contour arrives at the optimization problem where several efficient methods can be applied. In a simple model with a serious sign problem, the path optimization method is demonstrated to work well; the residual sign problem is resolved and precise results can be obtained even in the region where the global sign problem is serious.

  7. Monte Carlo method for solving a parabolic problem

    Directory of Open Access Journals (Sweden)

    Tian Yi

    2016-01-01

    Full Text Available In this paper, we present a numerical method based on random sampling for a parabolic problem. This method combines use of the Crank-Nicolson method and Monte Carlo method. In the numerical algorithm, we first discretize governing equations by Crank-Nicolson method, and obtain a large sparse system of linear algebraic equations, then use Monte Carlo method to solve the linear algebraic equations. To illustrate the usefulness of this technique, we apply it to some test problems.

  8. A guided interview process to improve student pharmacists' identification of drug therapy problems.

    Science.gov (United States)

    Rovers, John; Miller, Michael J; Koenigsfeld, Carrie; Haack, Sally; Hegge, Karly; McCleeary, Erin

    2011-02-10

    To measure agreement between advanced pharmacy practice experience students using a guided interview process and experienced clinical pharmacists using standard practices to identify drug therapy problems. Student pharmacists enrolled in an advanced pharmacy practice experience (APPE) and clinical pharmacists conducted medication therapy management interviews to identify drug therapy problems in elderly patients recruited from the community. Student pharmacists used a guided interview tool, while clinical pharmacists' interviews were conducted using their usual and customary practices. Student pharmacists also were surveyed to determine their perceptions of the interview tool. Fair to moderate agreement was observed on student and clinical pharmacists' identification of 4 of 7 drug therapy problems. Of those, agreement was significantly higher than chance for 3 drug therapy problems (adverse drug reaction, dosage too high, and needs additional drug therapy) and not significant for 1 (unnecessary drug therapy). Students strongly agreed that the interview tool was useful but agreed less strongly on recommending its use in practice. The guided interview process served as a useful teaching aid to assist student pharmacists to identify drug therapy problems.

  9. Analytical methods for heat transfer and fluid flow problems

    CERN Document Server

    Weigand, Bernhard

    2015-01-01

    This book describes useful analytical methods by applying them to real-world problems rather than solving the usual over-simplified classroom problems. The book demonstrates the applicability of analytical methods even for complex problems and guides the reader to a more intuitive understanding of approaches and solutions. Although the solution of Partial Differential Equations by numerical methods is the standard practice in industries, analytical methods are still important for the critical assessment of results derived from advanced computer simulations and the improvement of the underlying numerical techniques. Literature devoted to analytical methods, however, often focuses on theoretical and mathematical aspects and is therefore useless to most engineers. Analytical Methods for Heat Transfer and Fluid Flow Problems addresses engineers and engineering students. The second edition has been updated, the chapters on non-linear problems and on axial heat conduction problems were extended. And worked out exam...

  10. Alcohol- and drug-related absenteeism: a costly problem.

    Science.gov (United States)

    Roche, Ann; Pidd, Ken; Kostadinov, Victoria

    2016-06-01

    Absenteeism related to alcohol and other drug (AOD) use can place a substantial burden on businesses and society. This study estimated the cost of AOD-related absenteeism in Australia using a nationally representative dataset. A secondary analysis of the 2013 National Drug Strategy Household Survey (n=12,196) was undertaken. Two measures of AOD-related absenteeism were used: participants' self-reported absence due to AOD use (M1); and the mean difference in absence due to any illness/injury for AOD users compared to abstainers (M2). Both figures were multiplied by $267.70 (average day's wage in 2013 plus 20% on-costs) to estimate associated costs. M1 resulted in an estimation of 2.5 million days lost annually due to AOD use, at a cost of more than $680 million. M2 resulted in an estimation of almost 11.5 million days lost, at a cost of $3 billion. AOD-related absenteeism represents a significant and preventable impost upon Australian businesses. Workplaces should implement evidence-based interventions to promote healthy employee behaviour and reduce AOD-related absenteeism. © 2015 Public Health Association of Australia.

  11. Iterative methods for tomography problems: implementation to a cross-well tomography problem

    Science.gov (United States)

    Karadeniz, M. F.; Weber, G. W.

    2018-01-01

    The velocity distribution between two boreholes is reconstructed by cross-well tomography, which is commonly used in geology. In this paper, iterative methods, Kaczmarz’s algorithm, algebraic reconstruction technique (ART), and simultaneous iterative reconstruction technique (SIRT), are implemented to a specific cross-well tomography problem. Convergence to the solution of these methods and their CPU time for the cross-well tomography problem are compared. Furthermore, these three methods for this problem are compared for different tolerance values.

  12. Diffusion-synthetic acceleration methods for discrete-ordinates problems

    International Nuclear Information System (INIS)

    Larsen, E.W.

    1984-01-01

    The diffusion-synthetic acceleration (DSA) method is an iterative procedure for obtaining numerical solutions of discrete-ordinates problems. The DSA method is operationally more complicated than the standard source-iteration (SI) method, but if encoded properly it converges much more rapidly, especially for problems with diffusion-like regions. In this article we describe the basic ideas behind the DSA method and give a (roughly chronological) review of its long development. We conclude with a discussion which covers additional topics, including some remaining open problems an the status of current efforts aimed at solving these problems

  13. Inappropriate prescribing and prescribing omissions among drug-related problems using STOPP-START criteria

    NARCIS (Netherlands)

    Verdoorn, M.A.; Kwint, H.-F.; Faber, A.; L. Bouvy, M.

    2013-01-01

    Background and objectives: Medication review has been suggested as a way to prevent drug related problems (DRPs). Screening tools have been formulated to identify potentially inappropriate medicines (PIMs) and potential prescribing omissions (PPOs) respectively called Screening Tool of Older

  14. "Krokodil":revival of an old drug with new problems.

    Science.gov (United States)

    Gahr, Maximilian; Freudenmann, Roland W; Hiemke, Christoph; Gunst, Ingo M; Connemann, Bernhard J; Schönfeldt-Lecuona, Carlos

    2012-06-01

    In order to summarize current knowledge about the drug "Krokodil" a systematic review including a literature search of the databases PubMed, Embase, Scopus, and Google was conducted in December 2011. According to information acquired, "Krokodil" is a mixture of several substances and was first reported to have been used in Russia in 2003. The core agent of "Krokodil" is desomorphine, an opioid-analogue that can be easily and cheaply manufactured by oneself. Self-production results in a contaminated suspension that is injected intravenously. Due to its pharmacologic features, desomorphine shows a high potential to cause dependence. Against the background of first possible cases of "Krokodil" use in Western Europe, it appears advisable to provide information regarding the fatal consequences of "Krokodil."

  15. The problem of resistant Trichomonas vaginalis to antiprotozoal drugs

    Directory of Open Access Journals (Sweden)

    A. L. Poznyak

    2011-01-01

    Full Text Available This review presents recent data on the energy metabolism of Trichomonas vaginalis and ways the activation of metronidazole. The sensitivity of microorganisms to the 5-nitroimidazole by the presence of their enzyme systems, generating and transporting electrons, which can then transfer them to the nitro group of the drug. In T.vaginalis these are pyruvate ferredoxin-oxydoreductase, thioredoxin reductase and flavin reductase. The development of resistance T.vaginalis to metronidazole preparations of this multistep process, based on the gradual reduction (up to a loss activity hydrogenosomal enzymes and / or violation of the flavindependent metabolic pathways.

  16. Approaching the social control of drugs, I: Construction of the problem

    OpenAIRE

    Radulović Dragan

    2008-01-01

    The paper aims at outlining the social process whereby drug use has been defined as a major problem of contemporary society. The beginning of profane use of drugs is located in modern industrial society, while their global spread and the establishment of the prohibition system took place in the second half of 20th century. The generalized notion of drugs has dissolved into three different groups: some substances (coffee, tea, alcohol, tobacco) are socially accepted; others, like barbiturates ...

  17. Drug-Drug/Drug-Excipient Compatibility Studies on Curcumin using Non-Thermal Methods

    OpenAIRE

    Moorthi Chidambaram; Kathiresan Krishnasamy

    2014-01-01

    Purpose: Curcumin is a hydrophobic polyphenol isolated from dried rhizome of turmeric. Clinical usefulness of curcumin in the treatment of cancer is limited due to poor aqueous solubility, hydrolytic degradation, metabolism, and poor oral bioavailability. To overcome these limitations, we proposed to fabricate curcumin-piperine, curcumin-quercetin and curcumin-silibinin loaded polymeric nanoformulation. However, unfavourable combinations of drug-drug and drug-excipient may result in interacti...

  18. Cask manufacturing methods and quality assurance problems

    International Nuclear Information System (INIS)

    Riddle, J.H.; Cross, H.D.; Trujillo, A.A.; Pope, R.B.; Rack, H.J.

    1980-01-01

    This paper presents the results of a study performed to identify and evaluate cask manufacturing methods and materials which are presently or could be readily available in the United States. The study includes a comparison of the economic and technical advantages to be gained from manufacturing casks specifically for application to long-cooled fuel (5 years or greater) and waste materials. The conclusions that have been drawn from this study, which is still in progress are as follows: if spent fuel payloads are in fact cooled for five or more years prior to transportation there is a significant advantage to be gained from cask designs which are tailored to this longer cooling time; the most economic cask design is that which utilizes a lead gamma shield; the all-steel, single wall casks show substantial potential benefits resulting from ready availability and the cost and inspection advantages that result from the design simplicity; the future use of depleted uranium shielded casks in the United States is expected to be low as a result of the high cost and lack of manufacturing facilities; of the three types of neutron absorber systems evluated, the borated cast-in-place silicone rubber shows significant technical and cost advantages; and design and fabrication code requirements and regulatory requirements yet to be developed in the United States are likely to have a profound effect on the next generation of transportation casks

  19. Recovery from Problem Drug Use: What Can We Learn from the Dociologist Erving Goffman?

    Science.gov (United States)

    Neale, Joanne; Nettleton, Sarah; Pickering, Lucy

    2011-01-01

    In this commentary, we critically review the contribution of the sociologist Erving Goffman (1922-1982) to understanding recovery from problem drug use. Previous research has indicated that drug users have a "spoiled identity" and must restore a "normal" or "unspoiled" identity in order to recover. This argument has been linked to Goffman's…

  20. Using Lin's method to solve Bykov's problems

    Science.gov (United States)

    Knobloch, Jürgen; Lamb, Jeroen S. W.; Webster, Kevin N.

    2014-10-01

    We consider nonwandering dynamics near heteroclinic cycles between two hyperbolic equilibria. The constituting heteroclinic connections are assumed to be such that one of them is transverse and isolated. Such heteroclinic cycles are associated with the termination of a branch of homoclinic solutions, and called T-points in this context. We study codimension-two T-points and their unfoldings in Rn. In our consideration we distinguish between cases with real and complex leading eigenvalues of the equilibria. In doing so we establish Lin's method as a unified approach to (re)gain and extend results of Bykov's seminal studies and related works. To a large extent our approach reduces the study to the discussion of intersections of lines and spirals in the plane. Case (RR): Under open conditions on the eigenvalues, there exist open sets in parameter space for which there exist periodic orbits close to the heteroclinic cycle. In addition, there exist two one-parameter families of homoclinic orbits to each of the saddle points p1 and p2.See Theorem 2.1 and Proposition 2.2 for precise statements and Fig. 2 for bifurcation diagrams. Cases (RC) and (CC): At the bifurcation point μ=0 and for each N≥2, there exists an invariant set S0N close to the heteroclinic cycle on which the first return map is topologically conjugated to a full shift on N symbols. For any fixed N≥2, the invariant set SμN persists for |μ| sufficiently small.In addition, there exist infinitely many transversal and non-transversal heteroclinic orbits connecting the saddle points p1 and p2 in a neighbourhood of μ=0, as well as infinitely many one-parameter families of homoclinic orbits to each of the saddle points.For full statements of the results see Theorem 2.3 and Propositions 2.4, 2.5 and Fig. 3 for bifurcation diagrams. The dynamics near T-points has been studied previously by Bykov [6-10], Glendinning and Sparrow [20], Kokubu [27,28] and Labouriau and Rodrigues [30,31,38]. See also the surveys

  1. Finite element method for solving neutron transport problems

    International Nuclear Information System (INIS)

    Ferguson, J.M.; Greenbaum, A.

    1984-01-01

    A finite element method is introduced for solving the neutron transport equations. Our method falls into the category of Petrov-Galerkin solution, since the trial space differs from the test space. The close relationship between this method and the discrete ordinate method is discussed, and the methods are compared for simple test problems

  2. A Modified Alternating Direction Method for Variational Inequality Problems

    International Nuclear Information System (INIS)

    Han, D.

    2002-01-01

    The alternating direction method is an attractive method for solving large-scale variational inequality problems whenever the subproblems can be solved efficiently. However, the subproblems are still variational inequality problems, which are as structurally difficult to solve as the original one. To overcome this disadvantage, in this paper we propose a new alternating direction method for solving a class of nonlinear monotone variational inequality problems. In each iteration the method just makes an orthogonal projection to a simple set and some function evaluations. We report some preliminary computational results to illustrate the efficiency of the method

  3. Safety and problems in using radioactive drugs in hospitals

    International Nuclear Information System (INIS)

    Arimizu, Noboru

    1975-01-01

    The safety and the control problem of non-closed RI (radiopharmaceuticals) of which use has rapidly been increased, were studied. At present, the hospitals with an independent clinic for the nuclear medicine are very limited and many doctors, nurses and safety controllers who are working in the clinic belong to other clinics. As for the diagnosis using RI examination, the dangers of the persons who are working with radioimmunoassay, especially using Au-antigen kit were studied. Furthermore, the problems concerning the reduction of exposure dose by the use of a short half-life RI, such as sup(99m)Tc and the dangers of external exposure on the persons who use the isotope were studied. In addition, the control of RI ward for RI therapy was discussed. The author considered the specialization and fixation of doctors, nurses and technicians are becoming of necessity with the advancement of RI therapy. In addition, the necessity of training nurses for the nuclear medicine was insisted on. (Tsukamoto, Y.)

  4. Safety and problems in using radioactive drugs in hospitals

    Energy Technology Data Exchange (ETDEWEB)

    Arimizu, N [National Inst. of Radiological Sciences, Chiba (Japan)

    1975-01-01

    The safety and the control problem of non-closed RI (radiopharmaceuticals) of which use has rapidly been increased, were studied. At present, the hospitals with an independent clinic for the nuclear medicine are very limited and many doctors, nurses and safety controllers who are working in the clinic belong to other clinics. As for the diagnosis using RI examination, the dangers of the persons who are working with radioimmunoassay, especially using Au-antigen kit were studied. Furthermore, the problems concerning the reduction of exposure dose by the use of a short half-life RI, such as sup(99m)Tc and the dangers of external exposure on the persons who use the isotope were studied. In addition, the control of RI ward for RI therapy was discussed. The author considered the specialization and fixation of doctors, nurses and technicians are becoming of necessity with the advancement of RI therapy. In addition, the necessity of training nurses for the nuclear medicine was insisted on.

  5. Resolution and optimization methods for tour planning problems

    International Nuclear Information System (INIS)

    Vasserot, Jean-Pierre

    1976-12-01

    The aim of this study is to describe computerized methods for the resolution of the computer supported tour planning problem. After a presentation of this problem in operational research, the different existing methods of resolution are reviewed with the different approaches which have led to their elaboration. Different critics and comparisons are made on these methods and some improvements and new procedures are proposed, some of them allowing to solve more general problems. Finally, the structure of such a program, made at the CII to solve this kind of problem under multiple constraints is analysed [fr

  6. A New Drug Release Method in Early Development of Transdermal Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Bing Cai

    2012-01-01

    Full Text Available In vitro drug release tests are a widely used tool to measure the variance between transdermal product performances and required by many authorities. However, the result cannot provide a good estimation of the in vivo drug release. In the present work, a new method for measuring drug release from patches has been explored and compared with the conventional USP apparatus 2 and 5 methods. Durogesic patches, here used as a model patch, were placed on synthetic skin simulator and three moisture levels (29, 57, 198 μL cm−2 were evaluated. The synthetic skin simulators were collected after 1, 2, 3, 4, 6, and 24 hours and extracted with pH 1.0 hydrochloric acid solution. The drug concentrations in the extractions were measured by isocratic reverse phase high-pressure liquid chromatography. The results showed that, with the increasing moisture level on the synthetic skin simulator, the drug release rate increased. In comparison with the conventional USP method, the drug release results performed by the new method were in more correlation to the release rate claimed in the product label. This new method could help to differentiate the drug release rates among assorted formulations of transdermal drug delivery systems in the early stage of development.

  7. Mapped Fourier Methods for stiff problems in toroidal geometry

    OpenAIRE

    Guillard , Herve

    2014-01-01

    Fourier spectral or pseudo-spectral methods are usually extremely efficient for periodic problems. However this efficiency is lost if the solutions have zones of rapid variations or internal layers. For these cases, a large number of Fourier modes are required and this makes the Fourier method unpractical in many cases. This work investigates the use of mapped Fourier method as a way to circumvent this problem. Mapped Fourier method uses instead of the usual Fourier interpolant the compositio...

  8. Significance and challenges of stereoselectivity assessing methods in drug metabolism

    Directory of Open Access Journals (Sweden)

    Zhuowei Shen

    2016-02-01

    Full Text Available Stereoselectivity in drug metabolism can not only influence the pharmacological activities, tolerability, safety, and bioavailability of drugs directly, but also cause different kinds of drug–drug interactions. Thus, assessing stereoselectivity in drug metabolism is of great significance for pharmaceutical research and development (R&D and rational use in clinic. Although there are various methods available for assessing stereoselectivity in drug metabolism, many of them have shortcomings. The indirect method of chromatographic methods can only be applicable to specific samples with functional groups to be derivatized or form complex with a chiral selector, while the direct method achieved by chiral stationary phases (CSPs is expensive. As a detector of chromatographic methods, mass spectrometry (MS is highly sensitive and specific, whereas the matrix interference is still a challenge to overcome. In addition, the use of nuclear magnetic resonance (NMR and immunoassay in chiral analysis are worth noting. This review presents several typical examples of drug stereoselective metabolism and provides a literature-based evaluation on current chiral analytical techniques to show the significance and challenges of stereoselectivity assessing methods in drug metabolism.

  9. Regularization method for solving the inverse scattering problem

    International Nuclear Information System (INIS)

    Denisov, A.M.; Krylov, A.S.

    1985-01-01

    The inverse scattering problem for the Schroedinger radial equation consisting in determining the potential according to the scattering phase is considered. The problem of potential restoration according to the phase specified with fixed error in a finite range is solved by the regularization method based on minimization of the Tikhonov's smoothing functional. The regularization method is used for solving the problem of neutron-proton potential restoration according to the scattering phases. The determined potentials are given in the table

  10. The Unified Problem-Solving Method Development Language UPML

    OpenAIRE

    Fensel, Dieter; Motta, Enrico; van Harmelen, Frank; Benjamins, V. Richard; Crubezy, Monica; Decker, Stefan; Gaspari, Mauro; Groenboom, Rix; Grosso, William; Musen, Mark; Plaza, Enric; Schreiber, Guus; Studer, Rudi; Wielinga, Bob

    2003-01-01

    Problem-solving methods provide reusable architectures and components for implementing the reasoning part of knowledge-based systems. The UNIFIED PROBLEM-SOLVING METHOD DESCRIPTION LANGUAGE (UPML) has been developed to describe and implement such architectures and components to facilitate their semi-automatic reuse and adaptation. In a nutshell, UPML is a framework for developing knowledge-intensive reasoning systems based on libraries ofg eneric problem-solving components. The paper describe...

  11. The afforestation problem: a heuristic method based on simulated annealing

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    1992-01-01

    This paper presents the afforestation problem, that is the location and design of new forest compartments to be planted in a given area. This optimization problem is solved by a two-step heuristic method based on simulated annealing. Tests and experiences with this method are also presented....

  12. New complex variable meshless method for advection—diffusion problems

    International Nuclear Information System (INIS)

    Wang Jian-Fei; Cheng Yu-Min

    2013-01-01

    In this paper, an improved complex variable meshless method (ICVMM) for two-dimensional advection—diffusion problems is developed based on improved complex variable moving least-square (ICVMLS) approximation. The equivalent functional of two-dimensional advection—diffusion problems is formed, the variation method is used to obtain the equation system, and the penalty method is employed to impose the essential boundary conditions. The difference method for two-point boundary value problems is used to obtain the discrete equations. Then the corresponding formulas of the ICVMM for advection—diffusion problems are presented. Two numerical examples with different node distributions are used to validate and inestigate the accuracy and efficiency of the new method in this paper. It is shown that ICVMM is very effective for advection—diffusion problems, and has a good convergent character, accuracy, and computational efficiency

  13. Problem Drug Use, Marijuana, and European Projects: How Epidemiology Helped Czech Policy Reformers

    Directory of Open Access Journals (Sweden)

    Jan Morávek

    2008-12-01

    Full Text Available I examine the transfer of the Problem Drug Use (PDU concept into Czech scientific discourse through European institutions’ projects, and view PDU’s utilization by Czech researchers in relation to marijuana decriminalization efforts.PDU is defined as intravenous and/or long-term and regular use of opiates, cocaine, or amphetamines. Out of a vast array of illicit drug use patterns, this concept isolates a relatively small population with the riskiest use patterns to become the focus of public policies. A series of European Union and Council of Europe projects in 1990’s helped bring PDU into European research mainstream. The new common standard, promoted by the European Monitoring Centre for Drugs and Drug Addiction, was utilized by Czech authors in a 2001 policy analysis entitled “Impact Analysis Project of the New Drug Legislation in the Czech Republic” (PAD. PDU played a crucial role in PAD’s drug problem modeling, focusing on a “hard core” of opiate and methamphetamine users, while diverting attention from a large group of cannabis users.By using the new European methodological standard, PAD’s authors constructed marijuana as a non-problem. This helped drug policy reformers in the Czech Government legitimize their focus on “harder” drugs, and subsequently propose more lenient sanctions for the possession and cultivation of marijuana. I argue that continued ignorance of marijuana problems might jeopardize the tolerant expert-driven drug policy in the Czech Republic. Measurement of problem cannabis use should be introduced.

  14. Gradient-type methods in inverse parabolic problems

    International Nuclear Information System (INIS)

    Kabanikhin, Sergey; Penenko, Aleksey

    2008-01-01

    This article is devoted to gradient-based methods for inverse parabolic problems. In the first part, we present a priori convergence theorems based on the conditional stability estimates for linear inverse problems. These theorems are applied to backwards parabolic problem and sideways parabolic problem. The convergence conditions obtained coincide with sourcewise representability in the self-adjoint backwards parabolic case but they differ in the sideways case. In the second part, a variational approach is formulated for a coefficient identification problem. Using adjoint equations, a formal gradient of an objective functional is constructed. A numerical test illustrates the performance of conjugate gradient algorithm with the formal gradient.

  15. Data sources and methods for ascertaining human exposure to drugs.

    Science.gov (United States)

    Jones, J K; Kennedy, D L

    Estimates of population exposure based on drug use data are critical elements in the post marketing surveillance of drugs and provide a context for assessing the various risks and benefits associated with drug treatment. Such information is important in predicting morbidity and planning public health protection strategies, indepth studies, and regulatory actions. Knowledge that a population of one thousand instead of one million may potentially be exposed to a drug can help determine how a particular regulatory problem will be handled and would obviously be a major determinant in designing a case-control or cohort study. National estimates of drug use give an overview of the most commonly used drug therapies in current practice. They also furnish valuable comparison data for specific studies of drug use limited to one group of drugs, one geographic region, or one medical care setting. The FDA has access to several different national drug use data bases, each measuring a different point in the drug distribution channels. None covers the entire spectrum of drug exposures. The major "holes" in this patchwork of data bases are the inability to measure OTC drug use with any accuracy and the lack of qualitative information on drug use in hospitals. In addition, there is no patient linkage with the data. The data can only show trends in drug use. They impart no sense of the longitudinal use of drugs for individual patients. There is no direct connection between the different data bases, all of which have their own sampling frames and their own projection methodologies. The market research companies have complete control over these methodologies and they are subject to periodic changes, a situation not entirely satisfactory for epidemiologic research. Sometimes it is a struggle to keep up with these changes. Over the past two years, every one of these data bases has undergone some type of sampling or projection methodology change. One important limitation to the use of all

  16. Analytical Evaluation of Beam Deformation Problem Using Approximate Methods

    DEFF Research Database (Denmark)

    Barari, Amin; Kimiaeifar, A.; Domairry, G.

    2010-01-01

    The beam deformation equation has very wide applications in structural engineering. As a differential equation, it has its own problem concerning existence, uniqueness and methods of solutions. Often, original forms of governing differential equations used in engineering problems are simplified......, and this process produces noise in the obtained answers. This paper deals with the solution of second order of differential equation governing beam deformation using four analytical approximate methods, namely the Perturbation, Homotopy Perturbation Method (HPM), Homotopy Analysis Method (HAM) and Variational...... Iteration Method (VIM). The comparisons of the results reveal that these methods are very effective, convenient and quite accurate for systems of non-linear differential equation....

  17. Domain decomposition method for solving elliptic problems in unbounded domains

    International Nuclear Information System (INIS)

    Khoromskij, B.N.; Mazurkevich, G.E.; Zhidkov, E.P.

    1991-01-01

    Computational aspects of the box domain decomposition (DD) method for solving boundary value problems in an unbounded domain are discussed. A new variant of the DD-method for elliptic problems in unbounded domains is suggested. It is based on the partitioning of an unbounded domain adapted to the given asymptotic decay of an unknown function at infinity. The comparison of computational expenditures is given for boundary integral method and the suggested DD-algorithm. 29 refs.; 2 figs.; 2 tabs

  18. Prediction methods and databases within chemoinformatics: emphasis on drugs and drug candidates

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Jorgensen, FS; Brunak, Søren

    2005-01-01

    about drugs and drug candidates, and of databases with relevant properties. Access to experimental data and numerical methods for selecting and utilizing these data is crucial for developing accurate predictive in silico models. Many interesting predictive methods for classifying the suitability......MOTIVATION: To gather information about available databases and chemoinformatics methods for prediction of properties relevant to the drug discovery and optimization process. RESULTS: We present an overview of the most important databases with 2-dimensional and 3-dimensional structural information...... of chemical compounds as potential drugs, as well as for predicting their physico-chemical and ADMET properties have been proposed in recent years. These methods are discussed, and some possible future directions in this rapidly developing field are described....

  19. An assessment of factorial structure and health-related quality of life in problem drug users using the Short Form 36 Health Survey

    NARCIS (Netherlands)

    Buchholz, Angela; Krol, Anneke; Rist, Fred; Nieuwkerk, Pythia T.; Schippers, Gerard M.

    2008-01-01

    AIMS: To confirm the factorial structure of the Short Form 36 Health Survey (SF-36) in problem drug users and to compare their health-related quality of life (HRQOL) with general Dutch population norms. METHOD: Data of 394 participants from the Amsterdam Cohort Study among drug users, who had

  20. Recursive Monte Carlo method for deep-penetration problems

    International Nuclear Information System (INIS)

    Goldstein, M.; Greenspan, E.

    1980-01-01

    The Recursive Monte Carlo (RMC) method developed for estimating importance function distributions in deep-penetration problems is described. Unique features of the method, including the ability to infer the importance function distribution pertaining to many detectors from, essentially, a single M.C. run and the ability to use the history tape created for a representative region to calculate the importance function in identical regions, are illustrated. The RMC method is applied to the solution of two realistic deep-penetration problems - a concrete shield problem and a Tokamak major penetration problem. It is found that the RMC method can provide the importance function distributions, required for importance sampling, with accuracy that is suitable for an efficient solution of the deep-penetration problems considered. The use of the RMC method improved, by one to three orders of magnitude, the solution efficiency of the two deep-penetration problems considered: a concrete shield problem and a Tokamak major penetration problem. 8 figures, 4 tables

  1. Undocumented Immigration, Drug Problems, and Driving Under the Influence in the United States, 1990-2014.

    Science.gov (United States)

    Light, Michael T; Miller, Ty; Kelly, Brian C

    2017-09-01

    To examine the influence of undocumented immigration in the United States on 4 different metrics of drug and alcohol problems: drug arrests, drug overdose fatalities, driving under the influence (DUI) arrests, and DUI deaths. We combined newly developed state-level estimates of the undocumented population between 1990 and 2014 from the Center for Migration Studies with arrest data from the Federal Bureau of Investigation Uniform Crime Reports and fatality information from the Fatality Analysis Reporting System and the Centers for Disease Control and Prevention Underlying Cause of Death database. We used fixed-effects regression models to examine the longitudinal association between increased undocumented immigration and drug problems and drunk driving. Increased undocumented immigration was significantly associated with reductions in drug arrests, drug overdose deaths, and DUI arrests, net of other factors. There was no significant relationship between increased undocumented immigration and DUI deaths. This study provides evidence that undocumented immigration has not increased the prevalence of drug or alcohol problems, but may be associated with reductions in these public health concerns.

  2. A finite element method for flow problems in blast loading

    International Nuclear Information System (INIS)

    Forestier, A.; Lepareux, M.

    1984-06-01

    This paper presents a numerical method which describes fast dynamic problems in flow transient situations as in nuclear plants. A finite element formulation has been chosen; it is described by a preprocessor in CASTEM system: GIBI code. For these typical flow problems, an A.L.E. formulation for physical equations is used. So, some applications are presented: the well known problem of shock tube, the same one in 2D case and a last application to hydrogen detonation

  3. Properties and solution methods for large location-allocation problems

    DEFF Research Database (Denmark)

    Juel, Henrik; Love, Robert F.

    1982-01-01

    Location-allocation with l$ _p$ distances is studied. It is shown that this structure can be expressed as a concave minimization programming problem. Since concave minimization algorithms are not yet well developed, five solution methods are developed which utilize the special properties of the l......Location-allocation with l$ _p$ distances is studied. It is shown that this structure can be expressed as a concave minimization programming problem. Since concave minimization algorithms are not yet well developed, five solution methods are developed which utilize the special properties...... of the location-allocation problem. Using the rectilinear distance measure, two of these algorithms achieved optimal solutions in all 102 test problems for which solutions were known. The algorithms can be applied to much larger problems than any existing exact methods....

  4. A Novel Drug-Mouse Phenotypic Similarity Method Detects Molecular Determinants of Drug Effects.

    Directory of Open Access Journals (Sweden)

    Jeanette Prinz

    2016-09-01

    Full Text Available The molecular mechanisms that translate drug treatment into beneficial and unwanted effects are largely unknown. We present here a novel approach to detect gene-drug and gene-side effect associations based on the phenotypic similarity of drugs and single gene perturbations in mice that account for the polypharmacological property of drugs. We scored the phenotypic similarity of human side effect profiles of 1,667 small molecules and biologicals to profiles of phenotypic traits of 5,384 mouse genes. The benchmarking with known relationships revealed a strong enrichment of physical and indirect drug-target connections, causative drug target-side effect links as well as gene-drug links involved in pharmacogenetic associations among phenotypically similar gene-drug pairs. The validation by in vitro assays and the experimental verification of an unknown connection between oxandrolone and prokineticin receptor 2 reinforces the ability of this method to provide new molecular insights underlying drug treatment. Thus, this approach may aid in the proposal of novel and personalized treatments.

  5. Child abuse, drug addiction and mental health problems of incarcerated women in Israel.

    Science.gov (United States)

    Chen, Gila; Gueta, Keren

    2015-01-01

    The mental health problems and pathways to drug addiction and crime among female inmates have long been of interest to researchers and practitioners. The purpose of the current study was to examine the possible association between multiple types of childhood abuse, mental health problems, and drug addiction and the incarceration of 50 Israeli women in prison. The findings indicated that female inmates come from risky families with a high prevalence of family mental health problems, parental drug addiction and crime, and sibling drug addiction and crime. Furthermore, they revealed that incarcerated women from risky families were victims of multiple types of childhood abuse and neglect by their parents, as well as their siblings. Overall, the results suggest that the adverse consequences of a family's mental health problems are much more dramatic than we assumed to date, and that women are more likely than men to be the victims of multiple types of childhood abuse and neglect, as well as suffering more severe psychiatric problems, depression, and drug addiction. The implications of these findings are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Problems of the orthogonalized plane wave method. 1

    International Nuclear Information System (INIS)

    Farberovich, O.V.; Kurganskii, S.I.; Domashevskaya, E.P.

    1979-01-01

    The main problems of the orthogonalized plane wave method are discussed including (a) consideration of core states; (b) effect of overlap of wave functions of external core states upon the band structure; (c) calculation of d-type states. The modified orthogonal plane wave method (MOPW method) of Deegan and Twose is applied in a general form to solve the problems of the usual OPW method. For the first time the influence on the spectrum of the main parameters of the MOPW method is studied systematically by calculating the electronic energy spectrum in the transition metals Nb and V. (author)

  7. Distributed Interior-point Method for Loosely Coupled Problems

    DEFF Research Database (Denmark)

    Pakazad, Sina Khoshfetrat; Hansson, Anders; Andersen, Martin Skovgaard

    2014-01-01

    In this paper, we put forth distributed algorithms for solving loosely coupled unconstrained and constrained optimization problems. Such problems are usually solved using algorithms that are based on a combination of decomposition and first order methods. These algorithms are commonly very slow a...

  8. Active Subspace Methods for Data-Intensive Inverse Problems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qiqi [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2017-04-27

    The project has developed theory and computational tools to exploit active subspaces to reduce the dimension in statistical calibration problems. This dimension reduction enables MCMC methods to calibrate otherwise intractable models. The same theoretical and computational tools can also reduce the measurement dimension for calibration problems that use large stores of data.

  9. Information on actual medication use and drug-related problems in older patients: questionnaire or interview?

    Science.gov (United States)

    Willeboordse, Floor; Grundeken, Lucienne H; van den Eijkel, Lisanne P; Schellevis, François G; Elders, Petra J M; Hugtenburg, Jacqueline G

    2016-04-01

    Information on medication use and drug-related problems is important in the preparation of clinical medication reviews. Critical information can only be provided by patients themselves, but interviewing patients is time-consuming. Alternatively, patient information could be obtained with a questionnaire. In this study the agreement between patient information on medication use and drug-related problems in older patients obtained with a questionnaire was compared with information obtained during an interview. General practice in The Netherlands. A questionnaire was developed to obtain information on actual medication use and drug-related problems. Two patient groups ≥65 years were selected based on general practitioner electronic medical records in nine practices; I. polypharmacy and II. ≥1 predefined general geriatric problems. Eligible patients were asked to complete the questionnaire and were interviewed afterwards. Agreement on information on medication use and drug-related problems collected with the questionnaire and interview was calculated. Ninety-seven patients participated. Of all medications used, 87.6 % (95 % CI 84.7-90.5) was reported identically in the questionnaire and interview. Agreement for the complete medication list was found for 45.4 % (95 % CI 35.8-55.3) of the patients. On drug-related problem level, agreement between questionnaire and interview was 75 %. Agreement tended to be lower in vulnerable patients characterized by ≥4 chronic diseases, ≥10 medications used and low health literacy. Information from a questionnaire showed reasonable agreement compared with interviewing. The patients reported more medications and drug-related problems in the interview than the questionnaire. Taking the limitations into account, a questionnaire seems a suitable tool for medication reviews that may replace an interview for most patients.

  10. Application of meshless EFG method in fluid flow problems

    Indian Academy of Sciences (India)

    Meshless method; element-free Galerkin method; steady state analysis; transient ... fluid flow problems using the meshless element-free Galerkin method. The unknown function of velocity u ( x ) is approximated by moving least square ...

  11. Selecting The Best Initial Method For A Transportation Problem ...

    African Journals Online (AJOL)

    This paper is concerned with determining the best initial method for a transportation problem. Seven initial methods are considered and compared. One is a new method that has not been reported in the literature. Comparison is done on the basis of the number of iterations required to reach the final solution if the concerned ...

  12. Assessment of Environmental Problems and Methods of Waste ...

    African Journals Online (AJOL)

    FIRST LADY

    Keywords: Environment, Methods, Problems, and Waste Management. ... Solid waste management differs in developing countries like Nigeria, and in ..... References. Adegoke, O.S. ... Textbook of Public Health Medicine for the Tropics. 4th Ed.

  13. Mathematical programming methods for large-scale topology optimization problems

    DEFF Research Database (Denmark)

    Rojas Labanda, Susana

    for mechanical problems, but has rapidly extended to many other disciplines, such as fluid dynamics and biomechanical problems. However, the novelty and improvements of optimization methods has been very limited. It is, indeed, necessary to develop of new optimization methods to improve the final designs......, and at the same time, reduce the number of function evaluations. Nonlinear optimization methods, such as sequential quadratic programming and interior point solvers, have almost not been embraced by the topology optimization community. Thus, this work is focused on the introduction of this kind of second...... for the classical minimum compliance problem. Two of the state-of-the-art optimization algorithms are investigated and implemented for this structural topology optimization problem. A Sequential Quadratic Programming (TopSQP) and an interior point method (TopIP) are developed exploiting the specific mathematical...

  14. A direct sampling method to an inverse medium scattering problem

    KAUST Repository

    Ito, Kazufumi; Jin, Bangti; Zou, Jun

    2012-01-01

    In this work we present a novel sampling method for time harmonic inverse medium scattering problems. It provides a simple tool to directly estimate the shape of the unknown scatterers (inhomogeneous media), and it is applicable even when

  15. APPLICATION OF BOUNDARY INTEGRAL EQUATION METHOD FOR THERMOELASTICITY PROBLEMS

    Directory of Open Access Journals (Sweden)

    Vorona Yu.V.

    2015-12-01

    Full Text Available Boundary Integral Equation Method is used for solving analytically the problems of coupled thermoelastic spherical wave propagation. The resulting mathematical expressions coincide with the solutions obtained in a conventional manner.

  16. [Methods for teaching problem-solving in medical schools].

    Science.gov (United States)

    Shumway, J M; Vargas, M E; Heller, L E

    1984-01-01

    The need to include in the medical curriculum instructional activities to promote the development of problem-solving abilities has been asserted at the national and international levels. In research on the mental process involved in the solution of problems in medicine, problem-solving has been defined as a hypothetical-deductive activity engaged in by experienced physicians, in which the early generation of hypotheses influences the subsequent gathering of information. This article comments briefly on research on the mental process by which medical problems are solved. It describes the methods that research has shown to be most applicable in instruction to develop problem-solving abilities, and presents some educational principles that justify their application. The "trail-following" approach is the method that has been most commonly used to study the physician's problem-solving behavior. The salient conclusions from this research are that in the problem-solving process the diagnostic hypothesis is generated very early on and with limited data; the number of hypotheses is small; the problem-solving approach is specific to the type of medical problem and case in hand; and the accumulation of medical knowledge and experience forms the basis of clinical competence. Four methods for teaching the solution of problems are described: case presentation, the rain of ideas, the nominal groups technique and decision-making consensus, the census and analysis of forces in the field, and the analysis of clinical decisions. These methods are carried out in small groups. The advantages of the small groups are that the students are active participants in the learning process, they receive formative evaluation of their performance in a setting conductive to learning, and are able to interact with their instructor if he makes proper use of the right questioning techniques. While no single problem-solving method can be useful to all students or in all the problems they encounter

  17. Flux form Semi-Lagrangian methods for parabolic problems

    Directory of Open Access Journals (Sweden)

    Bonaventura Luca

    2016-09-01

    Full Text Available A semi-Lagrangian method for parabolic problems is proposed, that extends previous work by the authors to achieve a fully conservative, flux-form discretization of linear and nonlinear diffusion equations. A basic consistency and stability analysis is proposed. Numerical examples validate the proposed method and display its potential for consistent semi-Lagrangian discretization of advection diffusion and nonlinear parabolic problems.

  18. A PARALLEL NONOVERLAPPING DOMAIN DECOMPOSITION METHOD FOR STOKES PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Mei-qun Jiang; Pei-liang Dai

    2006-01-01

    A nonoverlapping domain decomposition iterative procedure is developed and analyzed for generalized Stokes problems and their finite element approximate problems in RN(N=2,3). The method is based on a mixed-type consistency condition with two parameters as a transmission condition together with a derivative-free transmission data updating technique on the artificial interfaces. The method can be applied to a general multi-subdomain decomposition and implemented on parallel machines with local simple communications naturally.

  19. Dimensional analysis and qualitative methods in problem solving: II

    International Nuclear Information System (INIS)

    Pescetti, D

    2009-01-01

    We show that the underlying mathematical structure of dimensional analysis (DA), in the qualitative methods in problem-solving context, is the algebra of the affine spaces. In particular, we show that the qualitative problem-solving procedure based on the parallel decomposition of a problem into simple special cases yields the new original mathematical concepts of special points and special representations of affine spaces. A qualitative problem-solving algorithm piloted by the mathematics of DA is illustrated by a set of examples.

  20. Problem Drug Use, Marijuana, and European Projects: How Epidemiology Helped Czech Policy Reformers

    OpenAIRE

    Jan Morávek

    2008-01-01

    I examine the transfer of the Problem Drug Use (PDU) concept into Czech scientific discourse through European institutions’ projects, and view PDU’s utilization by Czech researchers in relation to marijuana decriminalization efforts.PDU is defined as intravenous and/or long-term and regular use of opiates, cocaine, or amphetamines. Out of a vast array of illicit drug use patterns, this concept isolates a relatively small population with the riskiest use patterns to become the focus of public ...

  1. Factors influencing the detection rate of drug-related problems in community pharmacy

    DEFF Research Database (Denmark)

    Westerlund, T; Almarsdóttir, Anna Birna; Melander, A

    1999-01-01

    This study analyzes relationships between the number of drug-related problems detected in community pharmacy practice and the educational level and other characteristics of pharmacy personnel and their work sites. Random samples of pharmacists, prescriptionists and pharmacy technicians were drawn...... by each professional. The regression analysis showed the educational level of the professional to have a statistically significant effect on the detection rate, with pharmacists finding on average 2.5 more drug-related problems per 100 patients than prescriptionists and about 3.6 more than technicians....... The results of this study indicate the importance of education and training of pharmacy personnel in detection of drug-related problems. This findings speaks in favor of increasing the pharmacist to other personnel ratio, provided the higher costs will be offset by societal benefits....

  2. Problems in radiation shielding calculations with Monte Carlo methods

    International Nuclear Information System (INIS)

    Ueki, Kohtaro

    1985-01-01

    The Monte Carlo method is a very useful tool for solving a large class of radiation transport problem. In contrast with deterministic method, geometric complexity is a much less significant problem for Monte Carlo calculations. However, the accuracy of Monte Carlo calculations is of course, limited by statistical error of the quantities to be estimated. In this report, we point out some typical problems to solve a large shielding system including radiation streaming. The Monte Carlo coupling technique was developed to settle such a shielding problem accurately. However, the variance of the Monte Carlo results using the coupling technique of which detectors were located outside the radiation streaming, was still not enough. So as to bring on more accurate results for the detectors located outside the streaming and also for a multi-legged-duct streaming problem, a practicable way of ''Prism Scattering technique'' is proposed in the study. (author)

  3. Exercises and problems in mathematical methods of physics

    CERN Document Server

    Cicogna, Giampaolo

    2018-01-01

    This book presents exercises and problems in the mathematical methods of physics with the aim of offering undergraduate students an alternative way to explore and fully understand the mathematical notions on which modern physics is based. The exercises and problems are proposed not in a random order but rather in a sequence that maximizes their educational value. Each section and subsection starts with exercises based on first definitions, followed by groups of problems devoted to intermediate and, subsequently, more elaborate situations. Some of the problems are unavoidably "routine", but others bring to the forenontrivial properties that are often omitted or barely mentioned in textbooks. There are also problems where the reader is guided to obtain important results that are usually stated in textbooks without complete proofs. In all, some 350 solved problems covering all mathematical notions useful to physics are included. While the book is intended primarily for undergraduate students of physics, students...

  4. A New Iterative Method for Equilibrium Problems and Fixed Point Problems

    Directory of Open Access Journals (Sweden)

    Abdul Latif

    2013-01-01

    Full Text Available Introducing a new iterative method, we study the existence of a common element of the set of solutions of equilibrium problems for a family of monotone, Lipschitz-type continuous mappings and the sets of fixed points of two nonexpansive semigroups in a real Hilbert space. We establish strong convergence theorems of the new iterative method for the solution of the variational inequality problem which is the optimality condition for the minimization problem. Our results improve and generalize the corresponding recent results of Anh (2012, Cianciaruso et al. (2010, and many others.

  5. TRANSDERMAL DRUG DELIVERY AND METHODS TO ENHANCE IT

    Directory of Open Access Journals (Sweden)

    E. G. Kuznetsova

    2016-01-01

    Full Text Available The paper presents the common methods employed in recent years for enhancing transdermal delivery of drug substances when applying transdermal therapeutic delivery systems. The chemical, physical and mechanical methods to enhance the transport of macromolecular compounds through the skin are considered in details. 

  6. 49 CFR 40.203 - What problems cause a drug test to be cancelled unless they are corrected?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What problems cause a drug test to be cancelled unless they are corrected? 40.203 Section 40.203 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.203...

  7. Drug trajectories among youth undergoing treatment: the influence of psychological problems and delinquency.

    Science.gov (United States)

    Brunelle, Natacha; Bertrand, Karine; Beaudoin, Isabelle; Ledoux, Cinthia; Gendron, Annie; Arseneault, Catherine

    2013-08-01

    Previous research has documented associations of addiction with delinquency and psychological problems. However, few studies have evaluated their influence on adolescent's drug use trajectories. The current study aims to examine the influence of these factors on the recovery trajectories of 199 youths aged 15.6 years on average admitted to inpatient and outpatient addiction treatment centers, followed up three and six months later. Results indicate that youth who show higher severity of drug abuse exhibit greater improvement than youth with a lower severity of drug abuse at the onset of treatment. Although psychological problems were associated with baseline drug use, they did not influence drug use trajectory over time. Only delinquency influenced the recovery trajectories of these youth. Results suggest that a high level of delinquency can have a significant effect on the drug recovery process of adolescents and that interventions should attempt to reduce both drug use and delinquency. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  8. Are therapeutic vaccines an answer to the global problem of drug and alcohol abuse?

    Science.gov (United States)

    Brashier, Dick B S; Sharma, Ashok Kumar; Akhoon, Neha

    2016-01-01

    Drug Abuse has become a major challenging problem for the society. It effects people of all countries economical strata's and all ages. According. Monetary loss all over the world regarding drug abuse is in million dollars, it not only has an impact on human productivity and healthcare cost but also on cost of crimes conducted by these drugs and alcohol abuse. Therapeutic vaccine has come as new approach to deal with this problem, after failures in search for a pharmaceutical agent to deal with drug of abuse and alcohol. Research in field of nicotine abuse has gone a way ahead with number of vaccines being tried clinically followed by cocaine, opioids, methamphetamine, phencyclidine and alcohol. All of them have a common mechanism of action by antibody production whereas alcohol acts by genetic intervention. None have being approved yet due to poor results in phase II trials, possibly due to not able to trigger an adequate immunological response. But still quest is on for cracking the ice by developing first successful vaccine against drug of abuse, that would follow for other drugs too. It would be great step in field of therapeutic vaccines for drug abuse after similar successful vaccines being approved for other diseases like cancer.

  9. A theoretical study on a convergence problem of nodal methods

    Energy Technology Data Exchange (ETDEWEB)

    Shaohong, Z.; Ziyong, L. [Shanghai Jiao Tong Univ., 1954 Hua Shan Road, Shanghai, 200030 (China); Chao, Y. A. [Westinghouse Electric Company, P. O. Box 355, Pittsburgh, PA 15230-0355 (United States)

    2006-07-01

    The effectiveness of modern nodal methods is largely due to its use of the information from the analytical flux solution inside a homogeneous node. As a result, the nodal coupling coefficients depend explicitly or implicitly on the evolving Eigen-value of a problem during its solution iteration process. This poses an inherently non-linear matrix Eigen-value iteration problem. This paper points out analytically that, whenever the half wave length of an evolving node interior analytic solution becomes smaller than the size of that node, this non-linear iteration problem can become inherently unstable and theoretically can always be non-convergent or converge to higher order harmonics. This phenomenon is confirmed, demonstrated and analyzed via the simplest 1-D problem solved by the simplest analytic nodal method, the Analytic Coarse Mesh Finite Difference (ACMFD, [1]) method. (authors)

  10. Domain decomposition methods for solving an image problem

    Energy Technology Data Exchange (ETDEWEB)

    Tsui, W.K.; Tong, C.S. [Hong Kong Baptist College (Hong Kong)

    1994-12-31

    The domain decomposition method is a technique to break up a problem so that ensuing sub-problems can be solved on a parallel computer. In order to improve the convergence rate of the capacitance systems, pre-conditioned conjugate gradient methods are commonly used. In the last decade, most of the efficient preconditioners are based on elliptic partial differential equations which are particularly useful for solving elliptic partial differential equations. In this paper, the authors apply the so called covering preconditioner, which is based on the information of the operator under investigation. Therefore, it is good for various kinds of applications, specifically, they shall apply the preconditioned domain decomposition method for solving an image restoration problem. The image restoration problem is to extract an original image which has been degraded by a known convolution process and additive Gaussian noise.

  11. Alcohol and other drug problems in Australia: the urgent need for nurse education.

    Science.gov (United States)

    de Crespigny, C

    1996-07-01

    The economic, social and health costs associated with alcohol and other drug use, including medicines, impact on the Australian community profoundly. Many Australians use alcohol and other drugs (AODs) on a regular basis and a significant number experience problems at some time. There are about 25,000 drug-related deaths annually, the majority of which are related to alcohol and tobacco use. Many young people die or are injured as a direct result of alcohol intoxication, accidental overdose and related problems, and significant numbers of elderly people are hospitalised, permanently incapacitated or suffer avoidable trauma through adverse drug reactions and side-effects of medications. It is estimated that at least 25 per cent of acute hospital beds hold patients with alcohol-related problems directly associated with the medical diagnosis, and there are comparable numbers of people needing social and other forms of assistance at some time. Despite the preventative nature of many AOD problems and the call for harm reduction, timely intervention and support for the thousands of Australians attending hospitals, community health and mental health services, nurses are yet to effectively assist the community in preventing and responding to the range of AOD problems. Nursing policy, guidelines and clinical expertise are required to assist the community in addressing this issue. Undergraduate, postgraduate and continuing education have a vital role to play in providing the profession with the knowledge, skills and research base to meet this challenge.

  12. Prenatal alcohol use: the role of lifetime problems with alcohol, drugs, depression, and violence.

    Science.gov (United States)

    Flynn, Heather A; Chermack, Stephen T

    2008-07-01

    The purpose of this study was to examine a broader array of lifetime factors that theoretically may be associated with prenatal alcohol use than have previously been studied together, including family history of alcohol-use problems, history of physical or sexual abuse, lifetime major depressive disorder, alcohol-use disorder, illicit-drug-use problems, and partner violence. A total of 186 pregnant women, all of whom used alcohol in the year before pregnancy, were initially recruited in prenatal care settings. Women who reported no prenatal alcohol use (n = 96) were compared with women who drank 1-10 standard drinks during pregnancy (n = 75) and with women who drank more than 10 standard drinks during pregnancy (n = 13), considered to be a higher risk group, on the lifetime risk variables. Because of the public health implications, secondary analyses compared women who abstained during pregnancy with those who used any alcohol. Significant intercorrelations were found among most of the lifetime risk factors studied. Multivariate analyses showed that drug-use problems and partner violence were most strongly associated with prenatal alcohol use than any other variable studied. Consistent with a life span risk framework for alcohol-use problems, results of this study show that childhood abuse, familial alcoholism, lifetime major depressive disorder, and alcohol- and drug-use problems are interrelated. However, when considered together, only lifetime partner violence and drug use are significantly related to various levels of prenatal alcohol use. Identification, assessment, and intervention efforts should integrate these important factors.

  13. On multiple level-set regularization methods for inverse problems

    International Nuclear Information System (INIS)

    DeCezaro, A; Leitão, A; Tai, X-C

    2009-01-01

    We analyze a multiple level-set method for solving inverse problems with piecewise constant solutions. This method corresponds to an iterated Tikhonov method for a particular Tikhonov functional G α based on TV–H 1 penalization. We define generalized minimizers for our Tikhonov functional and establish an existence result. Moreover, we prove convergence and stability results of the proposed Tikhonov method. A multiple level-set algorithm is derived from the first-order optimality conditions for the Tikhonov functional G α , similarly as the iterated Tikhonov method. The proposed multiple level-set method is tested on an inverse potential problem. Numerical experiments show that the method is able to recover multiple objects as well as multiple contrast levels

  14. Proposal of Evolutionary Simplex Method for Global Optimization Problem

    Science.gov (United States)

    Shimizu, Yoshiaki

    To make an agile decision in a rational manner, role of optimization engineering has been notified increasingly under diversified customer demand. With this point of view, in this paper, we have proposed a new evolutionary method serving as an optimization technique in the paradigm of optimization engineering. The developed method has prospects to solve globally various complicated problem appearing in real world applications. It is evolved from the conventional method known as Nelder and Mead’s Simplex method by virtue of idea borrowed from recent meta-heuristic method such as PSO. Mentioning an algorithm to handle linear inequality constraints effectively, we have validated effectiveness of the proposed method through comparison with other methods using several benchmark problems.

  15. Modified Strum functions method in the nuclear three body problem

    International Nuclear Information System (INIS)

    Nasyrov, M.; Abdurakhmanov, A.; Yunusova, M.

    1997-01-01

    Fadeev-Hahn equations in the nuclear three-body problem were solved by modified Sturm functions method. Numerical calculations were carried out the square well potential. It was shown that the convergence of the method is high and the binding energy value is in agreement with experimental one (A.A.D.)

  16. Feed back Petrov-Galerkin methods for convection dominated problems

    International Nuclear Information System (INIS)

    Carmo, E.G.D. do; Galeao, A.C.

    1988-09-01

    The Petrov-Galerkin method is adaptively applied to convection dominated problems. To this end a feedback function is created which increases the control of derivatives in the direction of he gradient of the approximate solution. This leads to a method with good stability properties close to boundary layers and high accuracy in those regions where regular solutions do occur. (author) [pt

  17. Topological approximation methods for evolutionary problem of nonlinear hydrodynamics

    CERN Document Server

    Zvyagin, Victor

    2008-01-01

    The authors present functional analytical methods for solving a class of partial differential equations. The results have important applications to the numerical treatment of rheology (specific examples are the behaviour of blood or print colours) and to other applications in fluid mechanics. A class of methods for solving problems in hydrodynamics is presented.

  18. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: PROBLEM-SOLVING

    Directory of Open Access Journals (Sweden)

    Adela NEMEŞ

    2010-01-01

    Full Text Available We face with considerable challenge of developing students’ problem solving skills in our difficult environment. Good problem solving skills empower managers in their professional and personal lives. Problem solving skills are valued by academics and employers. The informations in Biology are often presented in abstract forms without contextualisation. Creative problem-solving process involves a few steps, which together provide a structured procedure for identifying challenges, generating ideas and implementing innovative solutions: identifying the problem, searching for possible solutions, selecting the most optimal solution and implementing a possible solution. Each aspect of personality has a different orientation to problem solving, different criteria for judging the effectiveness of the process and different associated strengths. Using real-world data in sample problems will also help facilitate the transfer process, since students can more easily identify with the context of a given situation. The paper describes the use of the Problem-Solving in Biology and the method of its administration. It also presents the results of a study undertaken to evaluate the value in teaching Biology. Problem-solving is seen as an essential skill that is developed in biology education.

  19. Novel Methods for Drug-Target Interaction Prediction using Graph Mining

    KAUST Repository

    Ba Alawi, Wail

    2016-08-31

    The problem of developing drugs that can be used to cure diseases is important and requires a careful approach. Since pursuing the wrong candidate drug for a particular disease could be very costly in terms of time and money, there is a strong interest in minimizing such risks. Drug repositioning has become a hot topic of research, as it helps reduce these risks significantly at the early stages of drug development by reusing an approved drug for the treatment of a different disease. Still, finding new usage for a drug is non-trivial, as it is necessary to find out strong supporting evidence that the proposed new uses of drugs are plausible. Many computational approaches were developed to narrow the list of possible candidate drug-target interactions (DTIs) before any experiments are done. However, many of these approaches suffer from unacceptable levels of false positives. We developed two novel methods based on graph mining networks of drugs and targets. The first method (DASPfind) finds all non-cyclic paths that connect a drug and a target, and using a function that we define, calculates a score from all the paths. This score describes our confidence that DTI is correct. We show that DASPfind significantly outperforms other state-of-the-art methods in predicting the top ranked target for each drug. We demonstrate the utility of DASPfind by predicting 15 novel DTIs over a set of ion channel proteins, and confirming 12 out of these 15 DTIs through experimental evidence reported in literature and online drug databases. The second method (DASPfind+) modifies DASPfind in order to increase the confidence and reliability of the resultant predictions. Based on the structure of the drug-target interaction (DTI) networks, we introduced an optimization scheme that incrementally alters the network structure locally for each drug to achieve more robust top 1 ranked predictions. Moreover, we explored effects of several similarity measures between the targets on the prediction

  20. Optimization methods for the Train Unit Shunting Problem

    DEFF Research Database (Denmark)

    Haahr, Jørgen Thorlund; Lusby, Richard Martin; Wagenaar, Joris Camiel

    2017-01-01

    We consider the Train Unit Shunting Problem, an important planning problem for passenger railway operators. This problem entails assigning train units from shunting yards to scheduled train services in such a way that the resulting operations are without conflicts. The problem arises at every...... shunting yard in the railway network and involves matching train units to arriving and departing train services as well as assigning the selected matchings to appropriate shunting yard tracks. We present an extensive comparison benchmark of multiple solution approaches for this problem, some of which...... are novel. In particular, we develop a constraint programming formulation, a column generation approach, and a randomized greedy heuristic. We compare and benchmark these approaches with two existing methods, a mixed integer linear program and a two-stage heuristic. The benchmark contains multiple real...

  1. Exact methods for time constrained routing and related scheduling problems

    DEFF Research Database (Denmark)

    Kohl, Niklas

    1995-01-01

    of customers. In the VRPTW customers must be serviced within a given time period - a so called time window. The objective can be to minimize operating costs (e.g. distance travelled), fixed costs (e.g. the number of vehicles needed) or a combination of these component costs. During the last decade optimization......This dissertation presents a number of optimization methods for the Vehicle Routing Problem with Time Windows (VRPTW). The VRPTW is a generalization of the well known capacity constrained Vehicle Routing Problem (VRP), where a fleet of vehicles based at a central depot must service a set...... of J?rnsten, Madsen and S?rensen (1986), which has been tested computationally by Halse (1992). Both methods decompose the problem into a series of time and capacity constrained shotest path problems. This yields a tight lower bound on the optimal objective, and the dual gap can often be closed...

  2. Domain decomposition methods for the neutron diffusion problem

    International Nuclear Information System (INIS)

    Guerin, P.; Baudron, A. M.; Lautard, J. J.

    2010-01-01

    The neutronic simulation of a nuclear reactor core is performed using the neutron transport equation, and leads to an eigenvalue problem in the steady-state case. Among the deterministic resolution methods, simplified transport (SPN) or diffusion approximations are often used. The MINOS solver developed at CEA Saclay uses a mixed dual finite element method for the resolution of these problems. and has shown his efficiency. In order to take into account the heterogeneities of the geometry, a very fine mesh is generally required, and leads to expensive calculations for industrial applications. In order to take advantage of parallel computers, and to reduce the computing time and the local memory requirement, we propose here two domain decomposition methods based on the MINOS solver. The first approach is a component mode synthesis method on overlapping sub-domains: several Eigenmodes solutions of a local problem on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second approach is an iterative method based on a non-overlapping domain decomposition with Robin interface conditions. At each iteration, we solve the problem on each sub-domain with the interface conditions given by the solutions on the adjacent sub-domains estimated at the previous iteration. Numerical results on parallel computers are presented for the diffusion model on realistic 2D and 3D cores. (authors)

  3. A Projected Conjugate Gradient Method for Sparse Minimax Problems

    DEFF Research Database (Denmark)

    Madsen, Kaj; Jonasson, Kristjan

    1993-01-01

    A new method for nonlinear minimax problems is presented. The method is of the trust region type and based on sequential linear programming. It is a first order method that only uses first derivatives and does not approximate Hessians. The new method is well suited for large sparse problems...... as it only requires that software for sparse linear programming and a sparse symmetric positive definite equation solver are available. On each iteration a special linear/quadratic model of the function is minimized, but contrary to the usual practice in trust region methods the quadratic model is only...... with the method are presented. In fact, we find that the number of iterations required is comparable to that of state-of-the-art quasi-Newton codes....

  4. The block Gauss-Seidel method in sound transmission problems

    OpenAIRE

    Poblet-Puig, Jordi; Rodríguez Ferran, Antonio

    2009-01-01

    Sound transmission through partitions can be modelled as an acoustic fluid-elastic structure interaction problem. The block Gauss-Seidel iterative method is used in order to solve the finite element linear system of equations. The blocks are defined in a natural way, respecting the fluid and structural domains. The convergence criterion (spectral radius of iteration matrix smaller than one) is analysed and interpreted in physical terms by means of simple one-dimensional problems. This anal...

  5. Solution Methods for the Periodic Petrol Station Replenishment Problem

    OpenAIRE

    C Triki

    2013-01-01

    In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP) over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ens...

  6. Adomian decomposition method for nonlinear Sturm-Liouville problems

    Directory of Open Access Journals (Sweden)

    Sennur Somali

    2007-09-01

    Full Text Available In this paper the Adomian decomposition method is applied to the nonlinear Sturm-Liouville problem-y" + y(tp=λy(t, y(t > 0, t ∈ I = (0, 1, y(0 = y(1 = 0, where p > 1 is a constant and λ > 0 is an eigenvalue parameter. Also, the eigenvalues and the behavior of eigenfuctions of the problem are demonstrated.

  7. Canonical transformations method in the potential scattering problem

    International Nuclear Information System (INIS)

    Pavlenko, Yu.G.

    1984-01-01

    Canonical formalism of the first order is used in the present paper to solve the problem of scattering and other problems of quantum mechanics. The theory of canonical transformations (CT) being the basis of hamiltonian approach permits to develop several methods of integration being beyond the scope of the standard theory of perturbations. In this case it is essential for numerical counting that the theory permits to obtain algorithm for plotting highest approximations

  8. Exact Methods for Solving the Train Departure Matching Problem

    DEFF Research Database (Denmark)

    Haahr, Jørgen Thorlund; Bull, Simon Henry

    In this paper we consider the train departure matching problem which is an important subproblem of the Rolling Stock Unit Management on Railway Sites problem introduced in the ROADEF/EURO Challenge 2014. The subproblem entails matching arriving train units to scheduled departing trains at a railway...... site while respecting multiple physical and operational constraints. In this paper we formally define that subproblem, prove its NP- hardness, and present two exact method approaches for solving the problem. First, we present a compact Mixed Integer Program formulation which we solve using a MIP solver...

  9. Use of refractometry and colorimetry as field methods to rapidly assess antimalarial drug quality.

    Science.gov (United States)

    Green, Michael D; Nettey, Henry; Villalva Rojas, Ofelia; Pamanivong, Chansapha; Khounsaknalath, Lamphet; Grande Ortiz, Miguel; Newton, Paul N; Fernández, Facundo M; Vongsack, Latsamy; Manolin, Ot

    2007-01-04

    The proliferation of counterfeit and poor-quality drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring drug quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the quality of the commonly available antimalarial drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess drug quality in resource-poor settings.

  10. Multi-frequency direct sampling method in inverse scattering problem

    Science.gov (United States)

    Kang, Sangwoo; Lambert, Marc; Park, Won-Kwang

    2017-10-01

    We consider the direct sampling method (DSM) for the two-dimensional inverse scattering problem. Although DSM is fast, stable, and effective, some phenomena remain unexplained by the existing results. We show that the imaging function of the direct sampling method can be expressed by a Bessel function of order zero. We also clarify the previously unexplained imaging phenomena and suggest multi-frequency DSM to overcome traditional DSM. Our method is evaluated in simulation studies using both single and multiple frequencies.

  11. Modified Differential Transform Method for Two Singular Boundary Values Problems

    Directory of Open Access Journals (Sweden)

    Yinwei Lin

    2014-01-01

    Full Text Available This paper deals with the two singular boundary values problems of second order. Two singular points are both boundary values points of the differential equation. The numerical solutions are developed by modified differential transform method (DTM for expanded point. Linear and nonlinear models are solved by this method to get more reliable and efficient numerical results. It can also solve ordinary differential equations where the traditional one fails. Besides, we give the convergence of this new method.

  12. SOLVING ENGINEERING OPTIMIZATION PROBLEMS WITH THE SWARM INTELLIGENCE METHODS

    Directory of Open Access Journals (Sweden)

    V. Panteleev Andrei

    2017-01-01

    Full Text Available An important stage in problem solving process for aerospace and aerostructures designing is calculating their main charac- teristics optimization. The results of the four constrained optimization problems related to the design of various technical systems: such as determining the best parameters of welded beams, pressure vessel, gear, spring are presented. The purpose of each task is to minimize the cost and weight of the construction. The object functions in optimization practical problem are nonlinear functions with a lot of variables and a complex layer surface indentations. That is why using classical approach for extremum seeking is not efficient. Here comes the necessity of using such methods of optimization that allow to find a near optimal solution in acceptable amount of time with the minimum waste of computer power. Such methods include the methods of Swarm Intelligence: spiral dy- namics algorithm, stochastic diffusion search, hybrid seeker optimization algorithm. The Swarm Intelligence methods are designed in such a way that a swarm consisting of agents carries out the search for extremum. In search for the point of extremum, the parti- cles exchange information and consider their experience as well as the experience of population leader and the neighbors in some area. To solve the listed problems there has been designed a program complex, which efficiency is illustrated by the solutions of four applied problems. Each of the considered applied optimization problems is solved with all the three chosen methods. The ob- tained numerical results can be compared with the ones found in a swarm with a particle method. The author gives recommenda- tions on how to choose methods parameters and penalty function value, which consider inequality constraints.

  13. Faculty Member's Handbook. Strategies for Preventing Alcohol and Other Drug Problems. The College Series.

    Science.gov (United States)

    CSR, Inc., Washington, DC.

    This handbook for higher education faculty is designed to inform them of the nature and extent of alcohol and other drug abuse on the nation's campuses and to enlist their involvement in responding to these problems. Based on the premise that each individual can make a difference, the faculty member is encouraged to help shape the campus…

  14. Identification of drug-related problems by a clinical pharmacist in addition to computerized alerts

    NARCIS (Netherlands)

    Zaal, R.J.; Jansen, M.; Duisenberg-van Essenberg, M.; C.C., Tijssen; Roukema, J.A.; van den Bemt, P.M.

    2013-01-01

    Background Both clinical pharmacists and computerized physician order entry systems with clinical decision support (CPOE/CDSS) can reduce drug-related problems (DRPs). However, the contribution of a clinical pharmacist in addition to CPOE/CDSS has not been established in a prospective study.

  15. Identification of drug-related problems by a clinical pharmacist in addition to computerized alerts

    NARCIS (Netherlands)

    R.J. Zaal (Rianne); M.M.P.M. Jansen (Mark M. P.); M. Duisenberg-Van Essenberg (Marjolijn); C.C. Tijssen (Cees); J.A. Roukema; P.M.L.A. van den Bemt (Patricia)

    2013-01-01

    textabstractBackground Both clinical pharmacists and computerized physician order entry systems with clinical decision support (CPOE/CDSS) can reduce drug-related problems (DRPs). However, the contribution of a clinical pharmacist in addition to CPOE/CDSS has not been established in a prospective

  16. Linear finite element method for one-dimensional diffusion problems

    Energy Technology Data Exchange (ETDEWEB)

    Brandao, Michele A.; Dominguez, Dany S.; Iglesias, Susana M., E-mail: micheleabrandao@gmail.com, E-mail: dany@labbi.uesc.br, E-mail: smiglesias@uesc.br [Universidade Estadual de Santa Cruz (LCC/DCET/UESC), Ilheus, BA (Brazil). Departamento de Ciencias Exatas e Tecnologicas. Laboratorio de Computacao Cientifica

    2011-07-01

    We describe in this paper the fundamentals of Linear Finite Element Method (LFEM) applied to one-speed diffusion problems in slab geometry. We present the mathematical formulation to solve eigenvalue and fixed source problems. First, we discretized a calculus domain using a finite set of elements. At this point, we obtain the spatial balance equations for zero order and first order spatial moments inside each element. Then, we introduce the linear auxiliary equations to approximate neutron flux and current inside the element and architect a numerical scheme to obtain the solution. We offer numerical results for fixed source typical model problems to illustrate the method's accuracy for coarse-mesh calculations in homogeneous and heterogeneous domains. Also, we compare the accuracy and computational performance of LFEM formulation with conventional Finite Difference Method (FDM). (author)

  17. Nodal methods for problems in fluid mechanics and neutron transport

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1985-01-01

    A new high-accuracy, coarse-mesh, nodal integral approach is developed for the efficient numerical solution of linear partial differential equations. It is shown that various special cases of this general nodal integral approach correspond to several high efficiency nodal methods developed recently for the numerical solution of neutron diffusion and neutron transport problems. The new approach is extended to the nonlinear Navier-Stokes equations of fluid mechanics; its extension to these equations leads to a new computational method, the nodal integral method which is implemented for the numerical solution of these equations. Application to several test problems demonstrates the superior computational efficiency of this new method over previously developed methods. The solutions obtained for several driven cavity problems are compared with the available experimental data and are shown to be in very good agreement with experiment. Additional comparisons also show that the coarse-mesh, nodal integral method results agree very well with the results of definitive ultra-fine-mesh, finite-difference calculations for the driven cavity problem up to fairly high Reynolds numbers

  18. Multigrid methods for S/sub N/ problems

    International Nuclear Information System (INIS)

    Nowak, P.F.; Larsen, E.W.; Martin, W.R.

    1987-01-01

    It has long been known that the standard source iteration (SI) method for obtaining iterative solutions of S/sub N/ problems is very slowly converging in optically thick regions with low absorption. The rebalance and diffusion synthetic acceleration (DSA) methods are generalizations of SI that have been developed to accelerate convergence, but neither of these methods has been completely successful. In particular, the rebalance method tends to become unstable in problems where it is needed most (problems with high scattering ratios c = 1), while the DSA method, to be implemented in a stable fashion, requires the solution of a particular system of acceleration equations, and this has been done efficiently in two-dimensional geometries only for the diamond difference S/sub N/ equations. This paper discusses another extension of the SI method, namely, SI combined with the spatial multigrid algorithm (SIMG). This appears to be a viable way to accelerate many S/sub N/ problems in multidimensional geometries, provided the finest mesh consists of cells that are not optically thick

  19. Solving a molecular docking problem by the modified PSO method

    Directory of Open Access Journals (Sweden)

    A. P. Karpenko

    2014-01-01

    Full Text Available The paper presents an canonical method of the swarm particles in two modifications to raise this method efficiency in solving multi-extreme problems of high dimension optimization. The essence of PSO-M1 modification is to form two new points to attract swarm particles (along with the points which are responsible for inertial, cognitive, and social components of canonical method. These new points represent the best points of sets of particles-neighbours of a given point. The modification aims to diversify search. All free parameters of the PSO-M1 method (as well as an canonical method are static. In contrast, one of such parameters of PSO-M2 modification is dynamic. So this modification represents an example of a self-adaptive method of optimization. The modification aims to intensify search. A computing experiment to study the method efficiency and its abovementioned modifications at solving the test problems of optimization showed advantages of offered modifications in comparison with canonical method, revealed a superiority of PSO-M2 modification both over canonical method, and over PSO-M1 modification. Using the PSO-M2 method allows us to solve the 28-dimensional molecular docking problem of HIV1 protease and darunaviry 3U7S as the molecules of receptor and a ligand, respectively. Results of computing experiment have shown that the PSO-M2 method successfully finds the position of ligand close to native and can be recommended for solving the molecular docking problems as an alternative to genetic algorithm.

  20. The spectral volume method as applied to transport problems

    International Nuclear Information System (INIS)

    McClarren, Ryan G.

    2011-01-01

    We present a new spatial discretization for transport problems: the spectral volume method. This method, rst developed by Wang for computational fluid dynamics, divides each computational cell into several sub-cells and enforces particle balance on each of these sub-cells. Also, these sub-cells are used to build a polynomial reconstruction in the cell. The idea of dividing cells into many cells is a generalization of the simple corner balance and other similar schemes. The spectral volume method preserves particle conservation and preserves the asymptotic diffusion limit. We present results from the method on two transport problems in slab geometry using discrete ordinates and second through sixth order spectral volume schemes. The numerical results demonstrate the accuracy and preservation of the diffusion limit of the spectral volume method. Future work will explore possible bene ts of the scheme for high-performance computing and for resolving diffusive boundary layers. (author)

  1. Drug therapy problems identification by clinical pharmacists in a private hospital in Kuwait.

    Science.gov (United States)

    Bayoud, T; Waheedi, M; Lemay, J; Awad, A

    2018-05-01

    To report the types and frequency of drug therapy problems (DTPs) identified and the physician acceptance of the clinical pharmacist interventions in a private hospital in Kuwait. A retrospective cross-sectional study was conducted on 3500 patients admitted to the hospital between December 2010 and April 2013. A structured approach was used to identify DTPs and recommend interventions. Data were analyzed using MAXQDA version 11. A total of 670 DTPs were identified and recommendations were proposed to treating physicians for each DTP. Overdosage was the most frequently identified drug therapy problem (30.8%), followed by low dosage (17.6%), unnecessary drug therapy (17.3%), need for additional drug therapy (11.6%), and need for different drug product (11.6%). The drug classes most frequently involved were anti-infectives (36.9%), analgesics (25.2%), and gastrointestinal agents (15.5%). More than two-third of the interventions (67.5%) were accepted and implemented by physicians. The most frequently accepted interventions were related to nonadherence, adverse drug reaction, monitoring parameters, inappropriate dosage, and need for additional drug therapy. The current findings expand the existing body of data by reporting on pharmacist recommendations of identified DTPs and importantly, their high rate of acceptance and implementation by the treating physician. These results could serve as a springboard to support further development and implementation of clinical pharmacy services in other healthcare settings in Kuwait. Copyright © 2018 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  2. Studying the factors in dependency to substances changing the mood and behavior and effective methods in drug addiction counseling

    Directory of Open Access Journals (Sweden)

    2004-05-01

    Full Text Available Addicts to alcohol and other substances changing the mood and behavior attempt to stop their addiction and avoid its relapse because they suffer mental and physical problems, they are under the pressure of family members, employer and other individuals who influence over their life as well as negative effects of drug addiction on their performance in family, work and social relations. Since drug addicts experience physical pain when they are not using drugs, they refer, at first, to physicians and then to psychiatrists. Although emerging and applying non-medical and non-pharmaceutical approaches models is not too old, arising various addictive drugs and increasing the number of drug addicts as well as individual/social destructive consequences of drug addiction have caused that psychiatrists, psychologists and social workers to represent various non-pharmaceutical theories, models, methods and guidelines based on the conditions of their clients and their clinical experiences. The present article attempts to identify the reasons of drug addiction tendency, consumption patterns, models, theories of addiction to substances changing the mood and behavior, various methods of drug treatment, effective methods in drug addiction counseling and non-medical and non-pharmaceutical methods to give up drug addiction by using recent research findings. On this basis, the most effective methods to help those who suffer from alcohol and other drugs abuse and dependency are studied.

  3. Computer methods in physics 250 problems with guided solutions

    CERN Document Server

    Landau, Rubin H

    2018-01-01

    Our future scientists and professionals must be conversant in computational techniques. In order to facilitate integration of computer methods into existing physics courses, this textbook offers a large number of worked examples and problems with fully guided solutions in Python as well as other languages (Mathematica, Java, C, Fortran, and Maple). It’s also intended as a self-study guide for learning how to use computer methods in physics. The authors include an introductory chapter on numerical tools and indication of computational and physics difficulty level for each problem.

  4. Application of Influence Function Method to the Fretting Wear Problems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Choon Yeol; Tian, Li Si; Bae, Joon Woo; Chai, Young Suck [Yeungnam University, Gyongsan (Korea, Republic of)

    2006-07-01

    Numerical analysis by influence function method (IFM) is demonstrated in this study in order to investigate the fretting wear problems on the secondary side of the steam generator, caused by flow induced vibration. Two-dimensional numerical contact model in terms of Cauchy integral equation is developed. The distributions of normal pressures, shear stresses and displacement fields are derived between two contact bodies which have similar elastic properties. The work rate model is adopted to find the wear amounts between two materials. The results are compared with the solutions by finite element analyses, which show the utilization of the present method to the fretting wear problems.

  5. Application of Influence Function Method to the Fretting Wear Problems

    International Nuclear Information System (INIS)

    Lee, Choon Yeol; Tian, Li Si; Bae, Joon Woo; Chai, Young Suck

    2006-01-01

    Numerical analysis by influence function method (IFM) is demonstrated in this study in order to investigate the fretting wear problems on the secondary side of the steam generator, caused by flow induced vibration. Two-dimensional numerical contact model in terms of Cauchy integral equation is developed. The distributions of normal pressures, shear stresses and displacement fields are derived between two contact bodies which have similar elastic properties. The work rate model is adopted to find the wear amounts between two materials. The results are compared with the solutions by finite element analyses, which show the utilization of the present method to the fretting wear problems

  6. Present-day Problems and Methods of Optimization in Mechatronics

    Directory of Open Access Journals (Sweden)

    Tarnowski Wojciech

    2017-06-01

    Full Text Available It is justified that design is an inverse problem, and the optimization is a paradigm. Classes of design problems are proposed and typical obstacles are recognized. Peculiarities of the mechatronic designing are specified as a proof of a particle importance of optimization in the mechatronic design. Two main obstacles of optimization are discussed: a complexity of mathematical models and an uncertainty of the value system, in concrete case. Then a set of non-standard approaches and methods are presented and discussed, illustrated by examples: a fuzzy description, a constraint-based iterative optimization, AHP ranking method and a few MADM functions in Matlab.

  7. A Maximum Entropy Method for a Robust Portfolio Problem

    Directory of Open Access Journals (Sweden)

    Yingying Xu

    2014-06-01

    Full Text Available We propose a continuous maximum entropy method to investigate the robustoptimal portfolio selection problem for the market with transaction costs and dividends.This robust model aims to maximize the worst-case portfolio return in the case that allof asset returns lie within some prescribed intervals. A numerical optimal solution tothe problem is obtained by using a continuous maximum entropy method. Furthermore,some numerical experiments indicate that the robust model in this paper can result in betterportfolio performance than a classical mean-variance model.

  8. Laboratory methods for diagnosis and detection of drug resistant ...

    African Journals Online (AJOL)

    Data source: Published series of peer reviewed journals and manuals written on laboratory methods that are currently used for diagnosis and detection of drug resistance of Mycobacterium tuberculosis complex were reviewed using the index medicus, pubmed and medline search. Conventional bacteriological microscopy ...

  9. Methods of using the quadratic assignment problem solution

    Directory of Open Access Journals (Sweden)

    Izabela Kudelska

    2012-09-01

    Full Text Available Background: Quadratic assignment problem (QAP is one of the most interesting of combinatorial optimization. Was presented by Koopman and Beckamanna in 1957, as a mathematical model of the location of indivisible tasks. This problem belongs to the class NP-hard issues. This forces the application to the solution already approximate methods for tasks with a small size (over 30. Even though it is much harder than other combinatorial optimization problems, it enjoys wide interest because it models the important class of decision problems. Material and methods: The discussion was an artificial intelligence tool that allowed to solve the problem QAP, among others are: genetic algorithms, Tabu Search, Branch and Bound. Results and conclusions: QAP did not arise directly as a model for certain actions, but he found its application in many areas. Examples of applications of the problem is: arrangement of buildings on the campus of the university, layout design of electronic components in systems with large scale integration (VLSI, design a hospital, arrangement of keys on the keyboard.

  10. Newton-type methods for optimization and variational problems

    CERN Document Server

    Izmailov, Alexey F

    2014-01-01

    This book presents comprehensive state-of-the-art theoretical analysis of the fundamental Newtonian and Newtonian-related approaches to solving optimization and variational problems. A central focus is the relationship between the basic Newton scheme for a given problem and algorithms that also enjoy fast local convergence. The authors develop general perturbed Newtonian frameworks that preserve fast convergence and consider specific algorithms as particular cases within those frameworks, i.e., as perturbations of the associated basic Newton iterations. This approach yields a set of tools for the unified treatment of various algorithms, including some not of the Newton type per se. Among the new subjects addressed is the class of degenerate problems. In particular, the phenomenon of attraction of Newton iterates to critical Lagrange multipliers and its consequences as well as stabilized Newton methods for variational problems and stabilized sequential quadratic programming for optimization. This volume will b...

  11. In silico machine learning methods in drug development.

    Science.gov (United States)

    Dobchev, Dimitar A; Pillai, Girinath G; Karelson, Mati

    2014-01-01

    Machine learning (ML) computational methods for predicting compounds with pharmacological activity, specific pharmacodynamic and ADMET (absorption, distribution, metabolism, excretion and toxicity) properties are being increasingly applied in drug discovery and evaluation. Recently, machine learning techniques such as artificial neural networks, support vector machines and genetic programming have been explored for predicting inhibitors, antagonists, blockers, agonists, activators and substrates of proteins related to specific therapeutic targets. These methods are particularly useful for screening compound libraries of diverse chemical structures, "noisy" and high-dimensional data to complement QSAR methods, and in cases of unavailable receptor 3D structure to complement structure-based methods. A variety of studies have demonstrated the potential of machine-learning methods for predicting compounds as potential drug candidates. The present review is intended to give an overview of the strategies and current progress in using machine learning methods for drug design and the potential of the respective model development tools. We also regard a number of applications of the machine learning algorithms based on common classes of diseases.

  12. Comparison of matrix methods for elastic wave scattering problems

    International Nuclear Information System (INIS)

    Tsao, S.J.; Varadan, V.K.; Varadan, V.V.

    1983-01-01

    This article briefly describes the T-matrix method and the MOOT (method of optimal truncation) of elastic wave scattering as they apply to A-D, SH- wave problems as well as 3-D elastic wave problems. Two methods are compared for scattering by elliptical cylinders as well as oblate spheroids of various eccentricity as a function of frequency. Convergence, and symmetry of the scattering cross section are also compared for ellipses and spheroidal cavities of different aspect ratios. Both the T-matrix approach and the MOOT were programmed on an AMDHL 470 computer using double precision arithmetic. Although the T-matrix method and MOOT are not always in agreement, it is in no way implied that any of the published results using MOOT are in error

  13. Drugs and Mental Health Problems among the Roma: Protective Factors Promoted by the Iglesia Evangélica Filadelfia

    Directory of Open Access Journals (Sweden)

    Jelen Amador López

    2018-02-01

    Full Text Available Background: High incidences of drug consumption and mental health problems are found among the Roma population in Spain, a reality that remains understudied. Past studies have indicated the positive role played by the Iglesia Evangélica Filadelfia (IEF in promoting rehabilitation and prevention of these practices. Objective: In this article, authors analyze in which ways the IEF favors processes of drug rehabilitation and mental health recovery as well as the prevention of these problems among its Roma members. Methods: A communicative qualitative approach was developed. It was communicative because new knowledge was created by dialogically contrasting the existing state of the art with study participants. It was qualitative because everyday life stories were collected, gathering the experiences, perceptions and interpretations of Roma people who are actively involved in three different IEF churches based in Barcelona. Results: This article identifies these protective factors: anti-drug discourse, a supportive environment, new social relations, role model status, the promotion of interactions, the revaluation of oneself, spiritual activities and the improvement of the feeling of belonging and the creation of meaning. Conclusion: The present research contributes new evidence to the current understanding of the role played by the IEF in improving Roma health status and how the identified protective factors can contribute to rehabilitation and recovery from such problems in other contexts.

  14. Drugs and Mental Health Problems among the Roma: Protective Factors Promoted by the Iglesia Evangélica Filadelfia.

    Science.gov (United States)

    López, Jelen Amador; García, Ramón Flecha; Martí, Teresa Sordé

    2018-02-14

    Background: High incidences of drug consumption and mental health problems are found among the Roma population in Spain, a reality that remains understudied. Past studies have indicated the positive role played by the Iglesia Evangélica Filadelfia (IEF) in promoting rehabilitation and prevention of these practices. Objective: In this article, authors analyze in which ways the IEF favors processes of drug rehabilitation and mental health recovery as well as the prevention of these problems among its Roma members. Methods: A communicative qualitative approach was developed. It was communicative because new knowledge was created by dialogically contrasting the existing state of the art with study participants. It was qualitative because everyday life stories were collected, gathering the experiences, perceptions and interpretations of Roma people who are actively involved in three different IEF churches based in Barcelona. Results: This article identifies these protective factors: anti-drug discourse, a supportive environment, new social relations, role model status, the promotion of interactions, the revaluation of oneself, spiritual activities and the improvement of the feeling of belonging and the creation of meaning. Conclusion: The present research contributes new evidence to the current understanding of the role played by the IEF in improving Roma health status and how the identified protective factors can contribute to rehabilitation and recovery from such problems in other contexts.

  15. Chronic illness and multimorbidity among problem drug users: a comparative cross sectional pilot study in primary care.

    LENUS (Irish Health Repository)

    Cullen, Walter

    2009-01-01

    BACKGROUND: Although multimorbidity has important implications for patient care in general practice, limited research has examined chronic illness and health service utilisation among problem drug users. This study aimed to determine chronic illness prevalence and health service utilisation among problem drug users attending primary care for methadone treatment, to compare these rates with matched \\'controls\\' and to develop and pilot test a valid study instrument. METHODS: A cross-sectional study of patients attending three large urban general practices in Dublin, Ireland for methadone treatment was conducted, and this sample was compared with a control group matched by practice, age, gender and General Medical Services (GMS) status. RESULTS: Data were collected on 114 patients. Fifty-seven patients were on methadone treatment, of whom 52(91%) had at least one chronic illness (other then substance use) and 39(68%) were prescribed at least one regular medication. Frequent utilisation of primary care services and secondary care services in the previous six months was observed among patients on methadone treatment and controls, although the former had significantly higher chronic illness prevalence and primary care contact rates. The study instrument facilitated data collection that was feasible and with minimal inter-observer variation. CONCLUSION: Multimorbidity is common among problem drug users attending general practice for methadone treatment. Primary care may therefore have an important role in primary and secondary prevention of chronic illnesses among this population. This study offers a feasible study instrument for further work on this issue. (238 words).

  16. Chronic illness and multimorbidity among problem drug users: a comparative cross sectional pilot study in primary care.

    LENUS (Irish Health Repository)

    Cullen, Walter

    2012-02-01

    BACKGROUND: Although multimorbidity has important implications for patient care in general practice, limited research has examined chronic illness and health service utilisation among problem drug users. This study aimed to determine chronic illness prevalence and health service utilisation among problem drug users attending primary care for methadone treatment, to compare these rates with matched \\'controls\\' and to develop and pilot test a valid study instrument. METHODS: A cross-sectional study of patients attending three large urban general practices in Dublin, Ireland for methadone treatment was conducted, and this sample was compared with a control group matched by practice, age, gender and General Medical Services (GMS) status. RESULTS: Data were collected on 114 patients. Fifty-seven patients were on methadone treatment, of whom 52(91%) had at least one chronic illness (other then substance use) and 39(68%) were prescribed at least one regular medication. Frequent utilisation of primary care services and secondary care services in the previous six months was observed among patients on methadone treatment and controls, although the former had significantly higher chronic illness prevalence and primary care contact rates. The study instrument facilitated data collection that was feasible and with minimal inter-observer variation. CONCLUSION: Multimorbidity is common among problem drug users attending general practice for methadone treatment. Primary care may therefore have an important role in primary and secondary prevention of chronic illnesses among this population. This study offers a feasible study instrument for further work on this issue. (238 words).

  17. Problems of Mathematical Finance by Stochastic Control Methods

    Science.gov (United States)

    Stettner, Łukasz

    The purpose of this paper is to present main ideas of mathematics of finance using the stochastic control methods. There is an interplay between stochastic control and mathematics of finance. On the one hand stochastic control is a powerful tool to study financial problems. On the other hand financial applications have stimulated development in several research subareas of stochastic control in the last two decades. We start with pricing of financial derivatives and modeling of asset prices, studying the conditions for the absence of arbitrage. Then we consider pricing of defaultable contingent claims. Investments in bonds lead us to the term structure modeling problems. Special attention is devoted to historical static portfolio analysis called Markowitz theory. We also briefly sketch dynamic portfolio problems using viscosity solutions to Hamilton-Jacobi-Bellman equation, martingale-convex analysis method or stochastic maximum principle together with backward stochastic differential equation. Finally, long time portfolio analysis for both risk neutral and risk sensitive functionals is introduced.

  18. Emerging Computational Methods for the Rational Discovery of Allosteric Drugs.

    Science.gov (United States)

    Wagner, Jeffrey R; Lee, Christopher T; Durrant, Jacob D; Malmstrom, Robert D; Feher, Victoria A; Amaro, Rommie E

    2016-06-08

    Allosteric drug development holds promise for delivering medicines that are more selective and less toxic than those that target orthosteric sites. To date, the discovery of allosteric binding sites and lead compounds has been mostly serendipitous, achieved through high-throughput screening. Over the past decade, structural data has become more readily available for larger protein systems and more membrane protein classes (e.g., GPCRs and ion channels), which are common allosteric drug targets. In parallel, improved simulation methods now provide better atomistic understanding of the protein dynamics and cooperative motions that are critical to allosteric mechanisms. As a result of these advances, the field of predictive allosteric drug development is now on the cusp of a new era of rational structure-based computational methods. Here, we review algorithms that predict allosteric sites based on sequence data and molecular dynamics simulations, describe tools that assess the druggability of these pockets, and discuss how Markov state models and topology analyses provide insight into the relationship between protein dynamics and allosteric drug binding. In each section, we first provide an overview of the various method classes before describing relevant algorithms and software packages.

  19. Numerical method of singular problems on singular integrals

    International Nuclear Information System (INIS)

    Zhao Huaiguo; Mou Zongze

    1992-02-01

    As first part on the numerical research of singular problems, a numerical method is proposed for singular integrals. It is shown that the procedure is quite powerful for solving physics calculation with singularity such as the plasma dispersion function. Useful quadrature formulas for some class of the singular integrals are derived. In general, integrals with more complex singularities can be dealt by this method easily

  20. Mixed isogeometric finite cell methods for the stokes problem

    NARCIS (Netherlands)

    Hoang, T.; Verhoosel, C.V.; Auricchio, F.; van Brummelen, E.H.; Reali, A.

    2017-01-01

    We study the application of the Isogeometric Finite Cell Method (IGA-FCM) to mixed formulations in the context of the Stokes problem. We investigate the performance of the IGA-FCM when utilizing some isogeometric mixed finite elements, namely: Taylor-Hood, Sub-grid, Raviart-Thomas, and Nédélec

  1. The lattice Boltzmann method and the problem of turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Djenidi, L. [School of Engineering The University of Newcastle, Callaghan NSW 2308 (Australia)

    2015-03-10

    This paper reports a brief review of numerical simulations of homogeneous isotopic turbulence (HIT) using the lattice Boltzmann method (LBM). The LBM results shows that the details of HIT are well captured and in agreement with existing data. This clearly indicates that the LBM is as good as current Navier-Stokes solvers and is very much adequate for investigating the problem of turbulence.

  2. The lattice Boltzmann method and the problem of turbulence

    International Nuclear Information System (INIS)

    Djenidi, L.

    2015-01-01

    This paper reports a brief review of numerical simulations of homogeneous isotopic turbulence (HIT) using the lattice Boltzmann method (LBM). The LBM results shows that the details of HIT are well captured and in agreement with existing data. This clearly indicates that the LBM is as good as current Navier-Stokes solvers and is very much adequate for investigating the problem of turbulence

  3. Methodical approaches to solving special problems of testing. Seminar papers

    International Nuclear Information System (INIS)

    1996-01-01

    This Seminar volume introduces concepts and applications from different areas of application of ultrasonic testing and other non-destructive test methods in 18 lectures, in order to give an idea of new trends in development and stimuli for special solutions to problems. 3 articles were recorded separately for the ENERGY data bank. (orig./MM) [de

  4. An efficient method for solving fractional Sturm-Liouville problems

    International Nuclear Information System (INIS)

    Al-Mdallal, Qasem M.

    2009-01-01

    The numerical approximation of the eigenvalues and the eigenfunctions of the fractional Sturm-Liouville problems, in which the second order derivative is replaced by a fractional derivative, is considered. The present results can be implemented on the numerical solution of the fractional diffusion-wave equation. The results show the simplicity and efficiency of the numerical method.

  5. Liouville's theorem and the method of the inverse problem

    International Nuclear Information System (INIS)

    Its, A.R.

    1985-01-01

    An approach to the investigation of the Zakharov-Shabat equations is developed. This approach is based on a classical theorem of Liouville and is the synthesis of ''finite-zone'' integration, the matrix Riemann problem method and the theory of isomonodromy deformations of differential equations. The effectiveness of the proposed scheme is demonstrated by developing ''dressing procedures'' for the Bullough-Dodd equation

  6. Assessment of Environmental Problems and Methods of Waste ...

    African Journals Online (AJOL)

    This study assessed the environmental problems and methods of waste management in Ado-Ekiti, Nigeria. Waste management is the collection, transportation, processing, recycling or disposal of waste materials, usually the one produced by human activities in an effort to reduce their effect on human health or on local ...

  7. A variational Bayesian method to inverse problems with impulsive noise

    KAUST Repository

    Jin, Bangti

    2012-01-01

    We propose a novel numerical method for solving inverse problems subject to impulsive noises which possibly contain a large number of outliers. The approach is of Bayesian type, and it exploits a heavy-tailed t distribution for data noise to achieve

  8. Methodical problems of basic education in nuclear engineering

    International Nuclear Information System (INIS)

    Meyer, K.

    1977-03-01

    The correct use of the one-group diffusion equation for the treatment of thermal reactors (especially PWR type reactors) is outlined. It is shown, that mistakes in some standard textbooks lead to bad results. Straight forward methods for the treatment of standard problems result from an exact interpretation of the model

  9. Evaluation of man-machine systems - methods and problems

    International Nuclear Information System (INIS)

    1985-01-01

    The symposium gives a survey of the methods of evaluation which permit as quantitive an assessment as possible of the collaboration between men and machines. This complex of problems is of great current significance in many areas of application. The systems to be evaluated are aircraft, land vehicles and watercraft as well as process control systems. (orig./GL) [de

  10. Nonconforming h-p spectral element methods for elliptic problems

    Indian Academy of Sciences (India)

    In [6,7,13,14] h-p spectral element methods for solving elliptic boundary value problems on polygonal ... Let M denote the number of corner layers and W denote the number of degrees of .... β is given by Theorem 2.2 of [3] which can be stated.

  11. Deflation in preconditioned conjugate gradient methods for Finite Element Problems

    NARCIS (Netherlands)

    Vermolen, F.J.; Vuik, C.; Segal, A.

    2002-01-01

    We investigate the influence of the value of deflation vectors at interfaces on the rate of convergence of preconditioned conjugate gradient methods applied to a Finite Element discretization for an elliptic equation. Our set-up is a Poisson problem in two dimensions with continuous or discontinuous

  12. Electrosynthesis methods and approaches for the preparative production of metabolites from parent drugs

    NARCIS (Netherlands)

    Gül, Turan; Bischoff, Rainer; Permentier, Hjalmar

    2015-01-01

    Identification of potentially toxic metabolites is important for drug discovery and development. Synthesis of drug metabolites is typically performed by organic synthesis or enzymatic methods, but is not always straightforward. Electrochemical (EC) methods are increasingly used to study drug

  13. Problem solving styles among people who use alcohol and other drugs in South Africa.

    Science.gov (United States)

    Sorsdahl, Katherine; Stein, Dan J; Carrara, Henri; Myers, Bronwyn

    2014-01-01

    The present study examines the relationship between problem-solving styles, socio-demographic variables and risk of alcohol and other drug (AOD)-related problems among a South African population. The Social Problem-Solving Inventory-Revised, Center for Epidemiologic Studies Depression Scale (CES-D) and the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) were administered to a convenience sample of 1000 respondents. According to the ASSIST, 32% and 49% of respondents met criteria for moderate to high risk of alcohol use and illicit drug use respectively. After adjusting for the effects of other variables in the model, respondents who were of "Coloured" ancestry (PR=1.20, 95% CI 1.0-1.4), male (PR=1.19, 95% CI 1.04-1.37), older (PR=1.01, 95% CI 1.00-1.02), who adopted an avoidance style of coping with problems (PR=1.03, 95% CI 1.01-1.05) and who met criteria for depression (PR=1.42, 95% CI 1.12-1.79) were more likely to be classified as having risky AOD use. This suggests that interventions to improve problem solving and provide people with cognitive strategies to cope better with their problems may hold promise for reducing risky AOD use. © 2013.

  14. A fuzzy logic based PROMETHEE method for material selection problems

    Directory of Open Access Journals (Sweden)

    Muhammet Gul

    2018-03-01

    Full Text Available Material selection is a complex problem in the design and development of products for diverse engineering applications. This paper presents a fuzzy PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluation method based on trapezoidal fuzzy interval numbers that can be applied to the selection of materials for an automotive instrument panel. Also, it presents uniqueness in making a significant contribution to the literature in terms of the application of fuzzy decision-making approach to material selection problems. The method is illustrated, validated, and compared against three different fuzzy MCDM methods (fuzzy VIKOR, fuzzy TOPSIS, and fuzzy ELECTRE in terms of its ranking performance. Also, the relationships between the compared methods and the proposed scenarios for fuzzy PROMETHEE are evaluated via the Spearman’s correlation coefficient. Styrene Maleic Anhydride and Polypropylene are determined optionally as suitable materials for the automotive instrument panel case. We propose a generic fuzzy MCDM methodology that can be practically implemented to material selection problem. The main advantages of the methodology are consideration of the vagueness, uncertainty, and fuzziness to decision making environment.

  15. The mimetic finite difference method for elliptic problems

    CERN Document Server

    Veiga, Lourenço Beirão; Manzini, Gianmarco

    2014-01-01

    This book describes the theoretical and computational aspects of the mimetic finite difference method for a wide class of multidimensional elliptic problems, which includes diffusion, advection-diffusion, Stokes, elasticity, magnetostatics and plate bending problems. The modern mimetic discretization technology developed in part by the Authors allows one to solve these equations on unstructured polygonal, polyhedral and generalized polyhedral meshes. The book provides a practical guide for those scientists and engineers that are interested in the computational properties of the mimetic finite difference method such as the accuracy, stability, robustness, and efficiency. Many examples are provided to help the reader to understand and implement this method. This monograph also provides the essential background material and describes basic mathematical tools required to develop further the mimetic discretization technology and to extend it to various applications.

  16. Finite cover method with mortar elements for elastoplasticity problems

    Science.gov (United States)

    Kurumatani, M.; Terada, K.

    2005-06-01

    Finite cover method (FCM) is extended to elastoplasticity problems. The FCM, which was originally developed under the name of manifold method, has recently been recognized as one of the generalized versions of finite element methods (FEM). Since the mesh for the FCM can be regular and squared regardless of the geometry of structures to be analyzed, structural analysts are released from a burdensome task of generating meshes conforming to physical boundaries. Numerical experiments are carried out to assess the performance of the FCM with such discretization in elastoplasticity problems. Particularly to achieve this accurately, the so-called mortar elements are introduced to impose displacement boundary conditions on the essential boundaries, and displacement compatibility conditions on material interfaces of two-phase materials or on joint surfaces between mutually incompatible meshes. The validity of the mortar approximation is also demonstrated in the elastic-plastic FCM.

  17. Application of the Least Squares Method in Axisymmetric Biharmonic Problems

    Directory of Open Access Journals (Sweden)

    Vasyl Chekurin

    2016-01-01

    Full Text Available An approach for solving of the axisymmetric biharmonic boundary value problems for semi-infinite cylindrical domain was developed in the paper. On the lateral surface of the domain homogeneous Neumann boundary conditions are prescribed. On the remaining part of the domain’s boundary four different biharmonic boundary pieces of data are considered. To solve the formulated biharmonic problems the method of least squares on the boundary combined with the method of homogeneous solutions was used. That enabled reducing the problems to infinite systems of linear algebraic equations which can be solved with the use of reduction method. Convergence of the solution obtained with developed approach was studied numerically on some characteristic examples. The developed approach can be used particularly to solve axisymmetric elasticity problems for cylindrical bodies, the heights of which are equal to or exceed their diameters, when on their lateral surface normal and tangential tractions are prescribed and on the cylinder’s end faces various types of boundary conditions in stresses in displacements or mixed ones are given.

  18. An Adaptive Pseudospectral Method for Fractional Order Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    Mohammad Maleki

    2012-01-01

    Full Text Available An adaptive pseudospectral method is presented for solving a class of multiterm fractional boundary value problems (FBVP which involve Caputo-type fractional derivatives. The multiterm FBVP is first converted into a singular Volterra integrodifferential equation (SVIDE. By dividing the interval of the problem to subintervals, the unknown function is approximated using a piecewise interpolation polynomial with unknown coefficients which is based on shifted Legendre-Gauss (ShLG collocation points. Then the problem is reduced to a system of algebraic equations, thus greatly simplifying the problem. Further, some additional conditions are considered to maintain the continuity of the approximate solution and its derivatives at the interface of subintervals. In order to convert the singular integrals of SVIDE into nonsingular ones, integration by parts is utilized. In the method developed in this paper, the accuracy can be improved either by increasing the number of subintervals or by increasing the degree of the polynomial on each subinterval. Using several examples including Bagley-Torvik equation the proposed method is shown to be efficient and accurate.

  19. REGULARIZED D-BAR METHOD FOR THE INVERSE CONDUCTIVITY PROBLEM

    DEFF Research Database (Denmark)

    Knudsen, Kim; Lassas, Matti; Mueller, Jennifer

    2009-01-01

    A strategy for regularizing the inversion procedure for the two-dimensional D-bar reconstruction algorithm based on the global uniqueness proof of Nachman [Ann. Math. 143 (1996)] for the ill-posed inverse conductivity problem is presented. The strategy utilizes truncation of the boundary integral...... the convergence of the reconstructed conductivity to the true conductivity as the noise level tends to zero. The results provide a link between two traditions of inverse problems research: theory of regularization and inversion methods based on complex geometrical optics. Also, the procedure is a novel...

  20. Solution Methods for the Periodic Petrol Station Replenishment Problem

    Directory of Open Access Journals (Sweden)

    C Triki

    2013-12-01

    Full Text Available In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ensuring a better quality solution. Our heuristics are tested and compared in two real-life cases, and our computational results show encouraging improvements with respect to a human planning solution

  1. A Predictor-Corrector Method for Solving Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Zong-Ke Bao

    2014-01-01

    Full Text Available We suggest and analyze a predictor-corrector method for solving nonsmooth convex equilibrium problems based on the auxiliary problem principle. In the main algorithm each stage of computation requires two proximal steps. One step serves to predict the next point; the other helps to correct the new prediction. At the same time, we present convergence analysis under perfect foresight and imperfect one. In particular, we introduce a stopping criterion which gives rise to Δ-stationary points. Moreover, we apply this algorithm for solving the particular case: variational inequalities.

  2. KARAKTERISTIK DAN ANALISIS DRUG RELATED PROBLEMS (DRPs PASIEN PENDERITA TUBERKULOSIS DI PUSKESMAS TEMINDUNG SAMARINDA KALIMANTAN TIMUR

    Directory of Open Access Journals (Sweden)

    Nurul Fauziah

    2014-12-01

    Full Text Available A study concerning the characteristics and Analysis of Drug Related Problems (DRPs Patients with Tuberculosis Patients in Public Health Center (PHC Temindung, Samarinda in East Kalimantan. The study was conducted using a prospective approach to the study of data sources in the form of primary data and secondary data. The primary data source is data from interviews with patients and through the provision of questionnaires and secondary data in this research is a Tuberculosis patient medical record data. Data collection was performed by analyzing the accuracy of the DRPs categories of accuracy of drugs, side effects and patient non-compliance. As well as the data recorded in the form of research support patient characteristics are age, sex, and education. Data were analyzed descriptively. Data obtained from patients with male gender 63.6% and women 36.4. Patient with age 50 years 27.3% . Based on the patient's level of education, no school 9.1%, graduated from elementary school22.7%, graduated from high school18.2%, graduated from high school40.1%, scholar 9.1%. Incidence of DRPs on drugs interactions 507%. Tuberculosis patient compliance rate of 81.8% in PHC Temindung adherent patients and 18.2% of patients do not comply Keywords: Tuberculosis, Drug Related Problems (DRPs drugs interactions and patient compliance   ABSTRAK Telah  dilakukan penelitian tentang Karakteristik dan Analisis Drug Related Problems(DRPs Pasien Penderita Tuberkulosis di Puskesmas Temindung, Samarinda Kalimantan Timur. Penelitian ini dilakukan dengan menggunakan pendekatan prospektif dengan sumber data penelitian berupa data primer dan data sekunder. Sumber data primer  adalah data hasil wawancara dengan pasien dan melalui pemberian kuisioner sedangkan data sekunder dalam penelitian ini adalah data rekam medik pasien Tuberkulosis. Pengumpulan data dilakukan dengan menganalisis DRPs kategori interaksi obat dan ketidakpatuhan pasien. Serta dicatat data pendukung penelitian

  3. Chebyshev Finite Difference Method for Fractional Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    Boundary

    2015-09-01

    Full Text Available This paper presents a numerical method for fractional differential equations using Chebyshev finite difference method. The fractional derivatives are described in the Caputo sense. Numerical results show that this method is of high accuracy and is more convenient and efficient for solving boundary value problems involving fractional ordinary differential equations. AMS Subject Classification: 34A08 Keywords and Phrases: Chebyshev polynomials, Gauss-Lobatto points, fractional differential equation, finite difference 1. Introduction The idea of a derivative which interpolates between the familiar integer order derivatives was introduced many years ago and has gained increasing importance only in recent years due to the development of mathematical models of a certain situations in engineering, materials science, control theory, polymer modelling etc. For example see [20, 22, 25, 26]. Most fractional order differential equations describing real life situations, in general do not have exact analytical solutions. Several numerical and approximate analytical methods for ordinary differential equation Received: December 2014; Accepted: March 2015 57 Journal of Mathematical Extension Vol. 9, No. 3, (2015, 57-71 ISSN: 1735-8299 URL: http://www.ijmex.com Chebyshev Finite Difference Method for Fractional Boundary Value Problems H. Azizi Taft Branch, Islamic Azad University Abstract. This paper presents a numerical method for fractional differential equations using Chebyshev finite difference method. The fractional derivative

  4. New high order FDTD method to solve EMC problems

    Directory of Open Access Journals (Sweden)

    N. Deymier

    2015-10-01

    Full Text Available In electromagnetic compatibility (EMC context, we are interested in developing new ac- curate methods to solve efficiently and accurately Maxwell’s equations in the time domain. Indeed, usual methods such as FDTD or FVTD present im- portant dissipative and/or dispersive errors which prevent to obtain a good numerical approximation of the physical solution for a given industrial scene unless we use a mesh with a very small cell size. To avoid this problem, schemes like the Discontinuous Galerkin (DG method, based on higher order spa- tial approximations, have been introduced and stud- ied on unstructured meshes. However the cost of this kind of method can become prohibitive accord- ing to the mesh used. In this paper, we first present a higher order spatial approximation method on carte- sian meshes. It is based on a finite element ap- proach and recovers at the order 1 the well-known Yee’s schema. Next, to deal with EMC problem, a non-oriented thin wire formalism is proposed for this method. Finally, several examples are given to present the benefits of this new method by compar- ison with both Yee’s schema and DG approaches.

  5. The nonconforming virtual element method for eigenvalue problems

    Energy Technology Data Exchange (ETDEWEB)

    Gardini, Francesca [Univ. of Pavia (Italy). Dept. of Mathematics; Manzini, Gianmarco [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vacca, Giuseppe [Univ. of Milano-Bicocca, Milan (Italy). Dept. of Mathematics and Applications

    2018-02-05

    We analyse the nonconforming Virtual Element Method (VEM) for the approximation of elliptic eigenvalue problems. The nonconforming VEM allow to treat in the same formulation the two- and three-dimensional case.We present two possible formulations of the discrete problem, derived respectively by the nonstabilized and stabilized approximation of the L2-inner product, and we study the convergence properties of the corresponding discrete eigenvalue problems. The proposed schemes provide a correct approximation of the spectrum and we prove optimal-order error estimates for the eigenfunctions and the usual double order of convergence of the eigenvalues. Finally we show a large set of numerical tests supporting the theoretical results, including a comparison with the conforming Virtual Element choice.

  6. On rational approximation methods for inverse source problems

    KAUST Repository

    Rundell, William

    2011-02-01

    The basis of most imaging methods is to detect hidden obstacles or inclusions within a body when one can only make measurements on an exterior surface. Such is the ubiquity of these problems, the underlying model can lead to a partial differential equation of any of the major types, but here we focus on the case of steady-state electrostatic or thermal imaging and consider boundary value problems for Laplace\\'s equation. Our inclusions are interior forces with compact support and our data consists of a single measurement of (say) voltage/current or temperature/heat flux on the external boundary. We propose an algorithm that under certain assumptions allows for the determination of the support set of these forces by solving a simpler "equivalent point source" problem, and which uses a Newton scheme to improve the corresponding initial approximation. © 2011 American Institute of Mathematical Sciences.

  7. Application of the kernel method to the inverse geosounding problem.

    Science.gov (United States)

    Hidalgo, Hugo; Sosa León, Sonia; Gómez-Treviño, Enrique

    2003-01-01

    Determining the layered structure of the earth demands the solution of a variety of inverse problems; in the case of electromagnetic soundings at low induction numbers, the problem is linear, for the measurements may be represented as a linear functional of the electrical conductivity distribution. In this paper, an application of the support vector (SV) regression technique to the inversion of electromagnetic data is presented. We take advantage of the regularizing properties of the SV learning algorithm and use it as a modeling technique with synthetic and field data. The SV method presents better recovery of synthetic models than Tikhonov's regularization. As the SV formulation is solved in the space of the data, which has a small dimension in this application, a smaller problem than that considered with Tikhonov's regularization is produced. For field data, the SV formulation develops models similar to those obtained via linear programming techniques, but with the added characteristic of robustness.

  8. On rational approximation methods for inverse source problems

    KAUST Repository

    Rundell, William; Hanke, Martin

    2011-01-01

    The basis of most imaging methods is to detect hidden obstacles or inclusions within a body when one can only make measurements on an exterior surface. Such is the ubiquity of these problems, the underlying model can lead to a partial differential equation of any of the major types, but here we focus on the case of steady-state electrostatic or thermal imaging and consider boundary value problems for Laplace's equation. Our inclusions are interior forces with compact support and our data consists of a single measurement of (say) voltage/current or temperature/heat flux on the external boundary. We propose an algorithm that under certain assumptions allows for the determination of the support set of these forces by solving a simpler "equivalent point source" problem, and which uses a Newton scheme to improve the corresponding initial approximation. © 2011 American Institute of Mathematical Sciences.

  9. Configuration space methods in the three-nucleon problem

    International Nuclear Information System (INIS)

    Friar, J.L.

    1985-01-01

    The assumptions underlying the formulation and solution of the Schroedinger equation for three nucleons in configuration space are reviewed. Those qualitative aspects of the two-nucleon problem which play an important role in the trinucleon are discussed. The geometrical aspects of the problem are developed, and the importance of the angular momentum barrier is demonstrated. The Faddeev-Noyes formulation of the Schroedinger equation is motivated, and the boundary conditions for various three-body problems is reviewed. The method of splines is shown to provide a particularly useful numerical modelling technique for solving the Faddeev-Noyes equation. The properties of explicit trinucleon solutions for various two-body force models are discussed, and the evidence for three-body forces is reviewed. The status of calculations of trinucleon observables is discussed, and conclusions are presented. 40 refs., 14 figs

  10. An outer approximation method for the road network design problem.

    Science.gov (United States)

    Asadi Bagloee, Saeed; Sarvi, Majid

    2018-01-01

    Best investment in the road infrastructure or the network design is perceived as a fundamental and benchmark problem in transportation. Given a set of candidate road projects with associated costs, finding the best subset with respect to a limited budget is known as a bilevel Discrete Network Design Problem (DNDP) of NP-hard computationally complexity. We engage with the complexity with a hybrid exact-heuristic methodology based on a two-stage relaxation as follows: (i) the bilevel feature is relaxed to a single-level problem by taking the network performance function of the upper level into the user equilibrium traffic assignment problem (UE-TAP) in the lower level as a constraint. It results in a mixed-integer nonlinear programming (MINLP) problem which is then solved using the Outer Approximation (OA) algorithm (ii) we further relax the multi-commodity UE-TAP to a single-commodity MILP problem, that is, the multiple OD pairs are aggregated to a single OD pair. This methodology has two main advantages: (i) the method is proven to be highly efficient to solve the DNDP for a large-sized network of Winnipeg, Canada. The results suggest that within a limited number of iterations (as termination criterion), global optimum solutions are quickly reached in most of the cases; otherwise, good solutions (close to global optimum solutions) are found in early iterations. Comparative analysis of the networks of Gao and Sioux-Falls shows that for such a non-exact method the global optimum solutions are found in fewer iterations than those found in some analytically exact algorithms in the literature. (ii) Integration of the objective function among the constraints provides a commensurate capability to tackle the multi-objective (or multi-criteria) DNDP as well.

  11. The unified method: III. Nonlinearizable problems on the interval

    International Nuclear Information System (INIS)

    Lenells, J; Fokas, A S

    2012-01-01

    Boundary value problems for integrable nonlinear evolution PDEs formulated on the finite interval can be analyzed by the unified method introduced by one of the authors and extensively used in the literature. The implementation of this general method to this particular class of problems yields the solution in terms of the unique solution of a matrix Riemann–Hilbert problem formulated in the complex k-plane (the Fourier plane), which has a jump matrix with explicit (x, t)-dependence involving six scalar functions of k, called the spectral functions. Two of these functions depend on the initial data, whereas the other four depend on all boundary values. The most difficult step of the new method is the characterization of the latter four spectral functions in terms of the given initial and boundary data, i.e. the elimination of the unknown boundary values. Here, we present an effective characterization of the spectral functions in terms of the given initial and boundary data. We present two different characterizations of this problem. One is based on the analysis of the so-called global relation, on the analysis of the equations obtained from the global relation via certain transformations leaving the dispersion relation of the associated linearized PDE invariant and on the computation of the large k asymptotics of the eigenfunctions defining the relevant spectral functions. The other is based on the analysis of the global relation and on the introduction of the so-called Gelfand–Levitan–Marchenko representations of the eigenfunctions defining the relevant spectral functions. We also show that these two different characterizations are equivalent and that in the limit when the length of the interval tends to infinity, the relevant formulas reduce to the analogous formulas obtained recently for the case of boundary value problems formulated on the half-line. (paper)

  12. An alternative extragradient projection method for quasi-equilibrium problems.

    Science.gov (United States)

    Chen, Haibin; Wang, Yiju; Xu, Yi

    2018-01-01

    For the quasi-equilibrium problem where the players' costs and their strategies both depend on the rival's decisions, an alternative extragradient projection method for solving it is designed. Different from the classical extragradient projection method whose generated sequence has the contraction property with respect to the solution set, the newly designed method possesses an expansion property with respect to a given initial point. The global convergence of the method is established under the assumptions of pseudomonotonicity of the equilibrium function and of continuity of the underlying multi-valued mapping. Furthermore, we show that the generated sequence converges to the nearest point in the solution set to the initial point. Numerical experiments show the efficiency of the method.

  13. Proposition of a method to formulate idea and innovation problems

    Directory of Open Access Journals (Sweden)

    Stéphane GORIA

    2010-01-01

    Full Text Available Nowadays, innovation is a major stake for development and durability of many companies and institution’s activities. In our work, we are interested in interpersonal communication problem in innovation context. We focus on the upstream of innovation process and we consider the means that can be used. First to leverage organisation’s innovation perspective and second to solve innovation problem proposed by a strategic decision maker. To do this, we believe that people charge with solving an innovation problem should manage some difficulties: to identify what can be an innovation for the decision maker, to define the objects with a big innovation potential, communicate to his possible partners the innovation field to investigate and to find ideas to innovate etc. Then, we try to identify and to present these ideas to contribute to decision making process. At this time when the Web is really the universal source with access to formidable information quantities, we use it to establish some creativity and idea sources for innovation. This paper presents a method to solve these communication problems. It presents a tool box which potentialities are illustrated by an example of the management of a “new chair” development problem.

  14. Heuristic Method for Decision-Making in Common Scheduling Problems

    Directory of Open Access Journals (Sweden)

    Edyta Kucharska

    2017-10-01

    Full Text Available The aim of the paper is to present a heuristic method for decision-making regarding an NP-hard scheduling problem with limitations related to tasks and the resources dependent on the current state of the process. The presented approach is based on the algebraic-logical meta-model (ALMM, which enables making collective decisions in successive process stages, not separately for individual objects or executors. Moreover, taking into account the limitations of the problem, it involves constructing only an acceptable solution and significantly reduces the amount of calculations. A general algorithm based on the presented method is composed of the following elements: preliminary analysis of the problem, techniques for the choice of decision at a given state, the pruning non-perspective trajectory, selection technique of the initial state for the trajectory final part, and the trajectory generation parameters modification. The paper includes applications of the presented approach to scheduling problems on unrelated parallel machines with a deadline and machine setup time dependent on the process state, where the relationship between tasks is defined by the graph. The article also presents the results of computational experiments.

  15. Primary drug resistance in a region with high burden of tuberculosis. A critical problem

    Directory of Open Access Journals (Sweden)

    Cecilia Villa-Rosas

    2015-03-01

    Full Text Available Objective. To determine rates of drug resistance in new cases of pulmonary tuberculosis in a region with a high burden of the disease. Materials and methods. New case suspects were referred for drug susceptibility testing. Results. 28.9% of new cases were resistant to at least one first line drug; 3.9% had a multidrug-resistant strain, 15.6% a monoresistant strain and 9.4% a polyresistant strain. Conclusion. Our rate of drug resistant tuberculosis in new cases is very high; this has important clinical implications, since even monoresistance can have a negative impact on the outcome of new cases treated empirically with a six month regimen.

  16. Comparing the Medicaid Retrospective Drug Utilization Review Program Cost-Savings Methods Used by State Agencies.

    Science.gov (United States)

    Prada, Sergio I

    2017-12-01

    The Medicaid Drug Utilization Review (DUR) program is a 2-phase process conducted by Medicaid state agencies. The first phase is a prospective DUR and involves electronically monitoring prescription drug claims to identify prescription-related problems, such as therapeutic duplication, contraindications, incorrect dosage, or duration of treatment. The second phase is a retrospective DUR and involves ongoing and periodic examinations of claims data to identify patterns of fraud, abuse, underutilization, drug-drug interaction, or medically unnecessary care, implementing corrective actions when needed. The Centers for Medicare & Medicaid Services requires each state to measure prescription drug cost-savings generated from its DUR programs on an annual basis, but it provides no guidance or unified methodology for doing so. To describe and synthesize the methodologies used by states to measure cost-savings using their Medicaid retrospective DUR program in federal fiscal years 2014 and 2015. For each state, the cost-savings methodologies included in the Medicaid DUR 2014 and 2015 reports were downloaded from Medicaid's website. The reports were then reviewed and synthesized. Methods described by the states were classified according to research designs often described in evaluation textbooks. In 2014, the most often used prescription drugs cost-savings estimation methodology for the Medicaid retrospective DUR program was a simple pre-post intervention method, without a comparison group (ie, 12 states). In 2015, the most common methodology used was a pre-post intervention method, with a comparison group (ie, 14 states). Comparisons of savings attributed to the program among states are still unreliable, because of a lack of a common methodology available for measuring cost-savings. There is great variation among states in the methods used to measure prescription drug utilization cost-savings. This analysis suggests that there is still room for improvement in terms of

  17. Physician assessments of drug seeking behavior: A mixed methods study.

    Directory of Open Access Journals (Sweden)

    Michael A Fischer

    Full Text Available Pain complaints are common, but clinicians are increasingly concerned about overuse of opioid pain medications. This may lead patients with actual pain to be stigmatized as "drug-seeking," or attempting to obtain medications they do not require medically. We assessed whether patient requests for specific opioid pain medication would lead physicians to classify them as drug-seeking and change management decisions.Mixed-methods analysis of interviews with 192 office-based primary care physicians after viewing video vignettes depicting patients presenting with back pain. For each presentation physicians were randomly assigned to see either an active request for a specific medication or a more general request for help with pain. The main outcome was assignment by the physician of "drug-seeking" as a potential diagnosis among patients presenting with back pain. Additional outcomes included other actions the physician would take and whether the physician would prescribe the medication requested. A potential diagnosis of drug-seeking behavior was included by 21% of physicians seeing a specific request for oxycodone vs. 3% for a general request for help with back pain(p<0.001. In multivariable models an active request was most strongly associated with a physician-assigned diagnosis of drug-seeking behavior(OR 8.10; 95% CI 2.11-31.15;p = 0.002; other major patient and physician characteristics, including gender and race, did not have strong associations with drug-seeking diagnosis. Physicians described short courses of opioid medications as a strategy for managing patients with pain while avoiding opioid overuse.When patients make a specific request for opioid pain medication, physicians are far more likely to suspect that they are drug-seeking. Physician suspicion of drug-seeking behavior did not vary by patient characteristics, including gender and race. The strategies used to assess patients further varied widely. These findings indicate a need for

  18. A variational Bayesian method to inverse problems with impulsive noise

    KAUST Repository

    Jin, Bangti

    2012-01-01

    We propose a novel numerical method for solving inverse problems subject to impulsive noises which possibly contain a large number of outliers. The approach is of Bayesian type, and it exploits a heavy-tailed t distribution for data noise to achieve robustness with respect to outliers. A hierarchical model with all hyper-parameters automatically determined from the given data is described. An algorithm of variational type by minimizing the Kullback-Leibler divergence between the true posteriori distribution and a separable approximation is developed. The numerical method is illustrated on several one- and two-dimensional linear and nonlinear inverse problems arising from heat conduction, including estimating boundary temperature, heat flux and heat transfer coefficient. The results show its robustness to outliers and the fast and steady convergence of the algorithm. © 2011 Elsevier Inc.

  19. Drug and alcohol abuse: The pattern and magnitude of the problem

    Energy Technology Data Exchange (ETDEWEB)

    Ajayi, P.A.

    1996-12-31

    In the last 12 months, many more cases of alcohol and drug (substance) abuse in the workplace were seen in the Escravos operations of Chevron Nigeria Limited than in previous years. This called the attention to the rising prevalence of drug and alcohol abuse in contradistinction to reports from similar organizations in other parts of the world. Chevron Nigeria has a written Drug and Alcohol Policy which has been dormant for some time because of the apparent rarity of the problem of substance abuse in the workplace. This Policy is being reviewed to broaden its scope and make it more effective. A total of 30 employees were tested for drugs and alcohol .6 exceeded the legal limits of Blood Alcohol Concentration (BAC) and 5 tested positive for drugs. Tests were mainly post-accident, reasonable cause and random. The common substances abused were alcohol, cannabis, cocaine and morphine in that order. The findings are compared with those of similar organizations in UK and USA. Efforts to control substance abuse in the workplace are being put into place.

  20. Quantum method of the inverse scattering problem. Pt. 1

    International Nuclear Information System (INIS)

    Sklyamin, E.K.; Takhtadzhyan, L.A.; Faddeev, L.D.

    1978-12-01

    In this work the authors use a formulation for the method of the inverse scattering problem for quantum-mechanical models of the field theory, that can be found in a quantization of these fully integrable systems. As the most important example serves the system (sinγ) 2 with the movement equation: γtt -γxx + m 2 /β sinβγ = 0 that is known under the specification Sine-Gordon-equation. (orig.) [de

  1. Development of numerical methods for thermohydraulic problems in reactor safety

    International Nuclear Information System (INIS)

    Chabrillac, M.; Kavenoky, A.; Le Coq, G.; L'Heriteau, J.P.; Stewart, B.; Rousseau, J.C.

    1976-01-01

    Numerical methods are being developed for the LOCA calculation; the first part is devoted to the BERTHA model and the associated characteristic treatment for the first seconds of the blowdown, the second part presents the problems encountered for accounting for velocity difference between phases. The FLIRA treatment of the reflooding is presented in the last part: this treatment allows the calculation of the quenching front velocity

  2. Spectral Analysis of Large Finite Element Problems by Optimization Methods

    Directory of Open Access Journals (Sweden)

    Luca Bergamaschi

    1994-01-01

    Full Text Available Recently an efficient method for the solution of the partial symmetric eigenproblem (DACG, deflated-accelerated conjugate gradient was developed, based on the conjugate gradient (CG minimization of successive Rayleigh quotients over deflated subspaces of decreasing size. In this article four different choices of the coefficient βk required at each DACG iteration for the computation of the new search direction Pk are discussed. The “optimal” choice is the one that yields the same asymptotic convergence rate as the CG scheme applied to the solution of linear systems. Numerical results point out that the optimal βk leads to a very cost effective algorithm in terms of CPU time in all the sample problems presented. Various preconditioners are also analyzed. It is found that DACG using the optimal βk and (LLT−1 as a preconditioner, L being the incomplete Cholesky factor of A, proves a very promising method for the partial eigensolution. It appears to be superior to the Lanczos method in the evaluation of the 40 leftmost eigenpairs of five finite element problems, and particularly for the largest problem, with size equal to 4560, for which the speed gain turns out to fall between 2.5 and 6.0, depending on the eigenpair level.

  3. Epidemiological methods for research with drug misusers: review of methods for studying prevalence and morbidity

    Directory of Open Access Journals (Sweden)

    Dunn John

    1999-01-01

    Full Text Available Epidemiological studies of drug misusers have until recently relied on two main forms of sampling: probability and convenience. The former has been used when the aim was simply to estimate the prevalence of the condition and the latter when in depth studies of the characteristics, profiles and behaviour of drug users were required, but each method has its limitations. Probability samples become impracticable when the prevalence of the condition is very low, less than 0.5% for example, or when the condition being studied is a clandestine activity such as illicit drug use. When stratified random samples are used, it may be difficult to obtain a truly representative sample, depending on the quality of the information used to develop the stratification strategy. The main limitation of studies using convenience samples is that the results cannot be generalised to the whole population of drug users due to selection bias and a lack of information concerning the sampling frame. New methods have been developed which aim to overcome some of these difficulties, for example, social network analysis, snowball sampling, capture-recapture techniques, privileged access interviewer method and contact tracing. All these methods have been applied to the study of drug misuse. The various methods are described and examples of their use given, drawn from both the Brazilian and international drug misuse literature.

  4. A direct sampling method to an inverse medium scattering problem

    KAUST Repository

    Ito, Kazufumi

    2012-01-10

    In this work we present a novel sampling method for time harmonic inverse medium scattering problems. It provides a simple tool to directly estimate the shape of the unknown scatterers (inhomogeneous media), and it is applicable even when the measured data are only available for one or two incident directions. A mathematical derivation is provided for its validation. Two- and three-dimensional numerical simulations are presented, which show that the method is accurate even with a few sets of scattered field data, computationally efficient, and very robust with respect to noises in the data. © 2012 IOP Publishing Ltd.

  5. The finite section method and problems in frame theory

    DEFF Research Database (Denmark)

    Christensen, Ole; Strohmer, T.

    2005-01-01

    solves related computational problems in frame theory. In the case of a frame which is localized w.r.t. an orthonormal basis we are able to estimate the rate of approximation. The results are applied to the reproducing kernel frame appearing in the theory for shift-invariant spaces generated by a Riesz......The finite section method is a convenient tool for approximation of the inverse of certain operators using finite-dimensional matrix techniques. In this paper we demonstrate that the method is very useful in frame theory: it leads to an efficient approximation of the inverse frame operator and also...

  6. The Adjoint Method for the Inverse Problem of Option Pricing

    Directory of Open Access Journals (Sweden)

    Shou-Lei Wang

    2014-01-01

    Full Text Available The estimation of implied volatility is a typical PDE inverse problem. In this paper, we propose the TV-L1 model for identifying the implied volatility. The optimal volatility function is found by minimizing the cost functional measuring the discrepancy. The gradient is computed via the adjoint method which provides us with an exact value of the gradient needed for the minimization procedure. We use the limited memory quasi-Newton algorithm (L-BFGS to find the optimal and numerical examples shows the effectiveness of the presented method.

  7. The quasidiffusion method for transport problems on unstructured meshes

    Science.gov (United States)

    Wieselquist, William A.

    2009-06-01

    In this work, we develop a quasidiffusion (QD) method for solving radiation transport problems on unstructured quadrilateral meshes in 2D Cartesian geometry, for example hanging-node meshes from adaptive mesh refinement (AMR) applications or skewed quadrilateral meshes from radiation hydrodynamics with Lagrangian meshing. The main result of the work is a new low-order quasidiffusion (LOQD) discretization on arbitrary quadrilaterals and a strategy for the efficient iterative solution which uses Krylov methods and incomplete LU factorization (ILU) preconditioning. The LOQD equations are a non-symmetric set of first-order PDEs that in second-order form resembles convection- diffusion with a diffusion tensor, with the difference that the LOQD equations contain extra cross-derivative terms. Our finite volume (FV) discretization of the LOQD equations is compared with three LOQD discretizations from literature. We then present a conservative, short characteristics discretization based on subcell balances (SCSB) that uses polynomial exponential moments to achieve robust behavior in various limits (e.g. small cells and voids) and is second- order accurate in space. A linear representation of the isotropic component of the scattering source based on face-average and cell-average scalar fluxes is also proposed and shown to be effective in some problems. In numerical tests, our QD method with linear scattering source representation shows some advantages compared to other transport methods. We conclude with avenues for future research and note that this QD method may easily be extended to arbitrary meshes in 3D Cartesian geometry.

  8. Resonating-group method for nuclear many-body problems

    International Nuclear Information System (INIS)

    Tang, Y.C.; LeMere, M.; Thompson, D.R.

    1977-01-01

    The resonating-group method is a microscopic method which uses fully antisymmetric wave functions, treats correctly the motion of the total center of mass, and takes cluster correlation into consideration. In this review, the formulation of this method is discussed for various nuclear many-body problems, and a complex-generator-coordinate technique which has been employed to evaluate matrix elements required in resonating-group calculations is described. Several illustrative examples of bound-state, scattering, and reaction calculations, which serve to demonstrate the usefulness of this method, are presented. Finally, by utilization of the results of these calculations, the role played by the Pauli principle in nuclear scattering and reaction processes is discussed. 21 figures, 2 tables, 185 references

  9. Ectoparasites of medical and veterinary importance: drug resistance and the need for alternative control methods.

    Science.gov (United States)

    McNair, Carol M

    2015-03-01

    Despite multiple attempts at eradication, many ectoparasites of humans and domestic livestock remain a persistent problem in the modern world. For many years, a range of pesticide drugs including organophosphates, organochlorides and synthetic pyrethroids provided effective control of these parasites; but intensive use of these drugs has led to the evolution of resistance in many target species. This paper aims to review the effectiveness of current control methods and discuss potential alternatives for the long term sustainable control of ectoparasites. Important medical ectoparasites such as scabies mites, head lice and bed bugs present a significant public health problem, and so adequate control methods are essential. Ectoparasites of domestic livestock and farmed fish (for example sheep scab mites, poultry mites and sea lice) are also of concern given the increasing strain on the world's food supply. These parasites have become resistant to several classes of pesticide, making control very difficult. Recently, an increasing amount of research has focussed on alternative control methods such as insect growth regulators, biological control using essential oils or fungi, as well as vaccine development against some ectoparasites of medical and veterinary importance. Drug resistance is prevalent in all of the ectoparasites discussed in this review. A wide variety of alternative control methods have been identified, however further research is necessary in order for these to be used to successfully control ectoparasitic diseases in the future. © 2015 Royal Pharmaceutical Society.

  10. Perioperative drug management. Reduction of potential drug-related problems in patients undergoing orthopaedic surgery by perioperative participation of a hospital pharmacist

    NARCIS (Netherlands)

    Duyvendak, M.; Bosman, J.; Klopotowska, J.; Kuiper-Herder, A.J.; Van Roon, E.N.; Brouwers, J.R.B.J.

    2007-01-01

    Objective: Drug management in the perioperative period is complex. Only little is known about the effects of clinical pharmaceutical care in this setting. The aim of this study was to determine the effect of a clinical pharmacy-based intervention on the number of potential drug-related problems in

  11. Reasons behind Greek problem drug users’ decisions to quit using drugs and engage in treatment of their own volition: sense of self and the Greek filotimo.

    Science.gov (United States)

    Fotopoulou, Maria

    2014-04-01

    The aim of this study was to explore Greek problem drug users’ perceptions of the reasons that led them to quit using drugs and engage in treatment of their own volition. Qualitative semi-structured in-depth interviews. Two state drug agencies in Thessaloniki, Greece. A total of 40 adult problem drug-using men and women participated in the study. Participants were asked to reflect on their decisions to wean themselves from drugs and enter treatment. Findings Participants reported that their decisions centred on the re-conceptualization of the drug-using community and their membership in it, the desire to restore aspects of identities thatwere deemed to be spoiled, and finally memories of their drug-free selves. The importance of the distinctively Greek notion of filotimo in this discussion is highlighted. Primarily in relation to filotimo (a concept that represents a complex array of virtues that regulates behaviour towards one’s family), the desire to restore one’s spoiled identity plays a pivotal role in Greek problem drug users’ decisions to cease drug use and engage in treatment.

  12. Substructure method in high-speed monorail dynamic problems

    Science.gov (United States)

    Ivanchenko, I. I.

    2008-12-01

    The study of actions of high-speed moving loads on bridges and elevated tracks remains a topical problem for transport. In the present study, we propose a new method for moving load analysis of elevated tracks (monorail structures or bridges), which permits studying the interaction between two strained objects consisting of rod systems and rigid bodies with viscoelastic links; one of these objects is the moving load (monorail rolling stock), and the other is the carrying structure (monorail elevated track or bridge). The methods for moving load analysis of structures were developed in numerous papers [1-15]. At the first stage, when solving the problem about a beam under the action of the simplest moving load such as a moving weight, two fundamental methods can be used; the same methods are realized for other structures and loads. The first method is based on the use of a generalized coordinate in the expansion of the deflection in the natural shapes of the beam, and the problem is reduced to solving a system of ordinary differential equations with variable coefficients [1-3]. In the second method, after the "beam-weight" system is decomposed, just as in the problem with the weight impact on the beam [4], solving the problem is reduced to solving an integral equation for the dynamic weight reaction [6, 7]. In [1-3], an increase in the number of retained forms leads to an increase in the order of the system of equations; in [6, 7], difficulties arise when solving the integral equations related to the conditional stability of the step procedures. The method proposed in [9, 14] for beams and rod systems combines the above approaches and eliminates their drawbacks, because it permits retaining any necessary number of shapes in the deflection expansion and has a resolving system of equations with an unconditionally stable integration scheme and with a minimum number of unknowns, just as in the method of integral equations [6, 7]. This method is further developed for

  13. The making of a public health problem: multi-drug resistant tuberculosis in India.

    Science.gov (United States)

    Engel, Nora C

    2013-07-01

    This paper examines how actors construct the public problem of multi-drug resistant tuberculosis (MDR-TB) in India. MDR-TB has been framed by the World Health Organization as a pressing, global public health problem. The responses to MDR-TB are complicated as treatment takes longer and is more expensive than routine TB treatment. This is particularly problematic in countries, such as India, with high patient loads, a large and unregulated private sector, weak health systems and potentially high numbers of MDR-TB cases. This paper analyses how actors struggle for control over ownership, causal theories and political responsibility of the public problem of MDR-TB in India. It combines Gusfield's theory on the construction of public problems with insights from literature on the social construction of diseases and on medical social control. It highlights that there are flexible definitions of public problems, which are negotiated among actor groups and which shift over time. The Indian government has shifted its policy in recent years and acknowledged that MDR-TB needs to be dealt with within the TB programme. The study results reveal how the policy shift happened, why debates on the construction of MDR-TB as a public problem in India continue, and why actors with alternative theories than the government do not succeed in their lobbying efforts. Two main arguments are put forward. First, the construction of the public problem of MDR-TB in India is a social and political process. The need for representative data, international influence and politics define what is controllable. Second, the government seems to be anxious to control the definition of India's MDR-TB problem. This impedes an open, critical and transparent discussion on the definition of the public problem of MDR-TB, which is important in responding flexibly to emerging public health challenges.

  14. Using Inverse Problem Methods with Surveillance Data in Pneumococcal Vaccination

    Science.gov (United States)

    Sutton, Karyn L.; Banks, H. T.; Castillo-Chavez, Carlos

    2010-01-01

    The design and evaluation of epidemiological control strategies is central to public health policy. While inverse problem methods are routinely used in many applications, this remains an area in which their use is relatively rare, although their potential impact is great. We describe methods particularly relevant to epidemiological modeling at the population level. These methods are then applied to the study of pneumococcal vaccination strategies as a relevant example which poses many challenges common to other infectious diseases. We demonstrate that relevant yet typically unknown parameters may be estimated, and show that a calibrated model may used to assess implemented vaccine policies through the estimation of parameters if vaccine history is recorded along with infection and colonization information. Finally, we show how one might determine an appropriate level of refinement or aggregation in the age-structured model given age-stratified observations. These results illustrate ways in which the collection and analysis of surveillance data can be improved using inverse problem methods. PMID:20209093

  15. Adaptive Finite Element Methods for Elliptic Problems with Discontinuous Coefficients

    KAUST Repository

    Bonito, Andrea; DeVore, Ronald A.; Nochetto, Ricardo H.

    2013-01-01

    Elliptic PDEs with discontinuous diffusion coefficients occur in application domains such as diffusions through porous media, electromagnetic field propagation on heterogeneous media, and diffusion processes on rough surfaces. The standard approach to numerically treating such problems using finite element methods is to assume that the discontinuities lie on the boundaries of the cells in the initial triangulation. However, this does not match applications where discontinuities occur on curves, surfaces, or manifolds, and could even be unknown beforehand. One of the obstacles to treating such discontinuity problems is that the usual perturbation theory for elliptic PDEs assumes bounds for the distortion of the coefficients in the L∞ norm and this in turn requires that the discontinuities are matched exactly when the coefficients are approximated. We present a new approach based on distortion of the coefficients in an Lq norm with q < ∞ which therefore does not require the exact matching of the discontinuities. We then use this new distortion theory to formulate new adaptive finite element methods (AFEMs) for such discontinuity problems. We show that such AFEMs are optimal in the sense of distortion versus number of computations, and report insightful numerical results supporting our analysis. © 2013 Societ y for Industrial and Applied Mathematics.

  16. Topicality of the problem of combined course of multi-drug resistant pulmonary tuberculosis with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    O. M. Raznatovska

    2017-08-01

    Full Text Available According to the World Health Organization, today in the world among the infectious chronic diseases one of the leading places and causes of death is multi-drug resistant tuberculosis of the lungs, and chronic non-communicable diseases – diabetes mellitus. The situation is complicated by the fact that the number of patients with combined course of these two heavy separate illnesses that complicate each other increases. It is established that with increasing severity of diabetes mellitus, tuberculosis process in the lungs becomes more complicate and deteriorates, and vice versa, the specific process complicates the course of diabetes mellitus, contributing to the development of diabetic complications. Against this background, the effectiveness of treatment of patients suffering from multi-drug resistant tuberculosis of the lungs in our country remains very low, mainly due to the toxic adverse reactions to antimycobacterial drugs of the reserve line, and in the case of adding diabetes mellitus, it deteriorates even more. The aim of this study was to review the scientific literature to determine the relevance of the study of combined course of multi-drug resistant tuberculosis of the lungs with diabetes mellitus and perspectives of innovative methods of diagnosis of diabetes mellitus. Early diagnosis of pre-diabetes, and autoimmune diseases will allow the use of timely correction techniques that prevents the development of diabetes mellitus, depending on its type, and in the future the development of serious irreversible processes, allow timely applying appropriate methods of correction of the revealed violations. Results. Very little amount of work is dedicated to the problem of combined course of multi-drug resistant tuberculosis of the lungs with diabetes mellitus, regardless of its type, the theme is relevant for today, in Ukraine there are no data regarding its study. This combined course of very difficult in the treatment diseases requires

  17. Prediction of Human Drug Targets and Their Interactions Using Machine Learning Methods: Current and Future Perspectives.

    Science.gov (United States)

    Nath, Abhigyan; Kumari, Priyanka; Chaube, Radha

    2018-01-01

    Identification of drug targets and drug target interactions are important steps in the drug-discovery pipeline. Successful computational prediction methods can reduce the cost and time demanded by the experimental methods. Knowledge of putative drug targets and their interactions can be very useful for drug repurposing. Supervised machine learning methods have been very useful in drug target prediction and in prediction of drug target interactions. Here, we describe the details for developing prediction models using supervised learning techniques for human drug target prediction and their interactions.

  18. Modified Block Newton method for the lambda modes problem

    Energy Technology Data Exchange (ETDEWEB)

    González-Pintor, S., E-mail: segonpin@isirym.upv.es [Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain); Ginestar, D., E-mail: dginestar@mat.upv.es [Instituto de Matemática Multidisciplinar, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain); Verdú, G., E-mail: gverdu@iqn.upv.es [Departamento de Ingeniería Química y Nuclear, Universidad Politécnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain)

    2013-06-15

    Highlights: ► The Modal Method is based on expanding the solution in a set of dominant modes. ► Updating the set of dominant modes improve its performance. ► A Modified Block Newton Method, which use previous calculated modes, is proposed. ► The method exhibits a very good local convergence with few iterations. ► Good performance results are also obtained for heavy perturbations. -- Abstract: To study the behaviour of nuclear power reactors it is necessary to solve the time dependent neutron diffusion equation using either a rectangular mesh for PWR and BWR reactors or a hexagonal mesh for VVER reactors. This problem can be solved by means of a modal method, which uses a set of dominant modes to expand the neutron flux. For the transient calculations using the modal method with a moderate number of modes, these modes must be updated each time step to maintain the accuracy of the solution. The updating modes process is also interesting to study perturbed configurations of a reactor. A Modified Block Newton method is studied to update the modes. The performance of the Newton method has been tested for a steady state perturbation analysis of two 2D hexagonal reactors, a perturbed configuration of the IAEA PWR 3D reactor and two configurations associated with a boron dilution transient in a BWR reactor.

  19. A New Method for Solving Supervised Data Classification Problems

    Directory of Open Access Journals (Sweden)

    Parvaneh Shabanzadeh

    2014-01-01

    Full Text Available Supervised data classification is one of the techniques used to extract nontrivial information from data. Classification is a widely used technique in various fields, including data mining, industry, medicine, science, and law. This paper considers a new algorithm for supervised data classification problems associated with the cluster analysis. The mathematical formulations for this algorithm are based on nonsmooth, nonconvex optimization. A new algorithm for solving this optimization problem is utilized. The new algorithm uses a derivative-free technique, with robustness and efficiency. To improve classification performance and efficiency in generating classification model, a new feature selection algorithm based on techniques of convex programming is suggested. Proposed methods are tested on real-world datasets. Results of numerical experiments have been presented which demonstrate the effectiveness of the proposed algorithms.

  20. An adaptive finite element method for steady and transient problems

    International Nuclear Information System (INIS)

    Benner, R.E. Jr.; Davis, H.T.; Scriven, L.E.

    1987-01-01

    Distributing integral error uniformly over variable subdomains, or finite elements, is an attractive criterion by which to subdivide a domain for the Galerkin/finite element method when localized steep gradients and high curvatures are to be resolved. Examples are fluid interfaces, shock fronts and other internal layers, as well as fluid mechanical and other boundary layers, e.g. thin-film states at solid walls. The uniform distribution criterion is developed into an adaptive technique for one-dimensional problems. Nodal positions can be updated simultaneously with nodal values during Newton iteration, but it is usually better to adopt nearly optimal nodal positions during Newton iteration upon nodal values. Three illustrative problems are solved: steady convection with diffusion, gradient theory of fluid wetting on a solid surface and Buckley-Leverett theory of two phase Darcy flow in porous media

  1. An improved partial bundle method for linearly constrained minimax problems

    Directory of Open Access Journals (Sweden)

    Chunming Tang

    2016-02-01

    Full Text Available In this paper, we propose an improved partial bundle method for solving linearly constrained minimax problems. In order to reduce the number of component function evaluations, we utilize a partial cutting-planes model to substitute for the traditional one. At each iteration, only one quadratic programming subproblem needs to be solved to obtain a new trial point. An improved descent test criterion is introduced to simplify the algorithm. The method produces a sequence of feasible trial points, and ensures that the objective function is monotonically decreasing on the sequence of stability centers. Global convergence of the algorithm is established. Moreover, we utilize the subgradient aggregation strategy to control the size of the bundle and therefore overcome the difficulty of computation and storage. Finally, some preliminary numerical results show that the proposed method is effective.

  2. A new DEA-GAHP method for supplier selection problem

    Directory of Open Access Journals (Sweden)

    Behrooz Ahadian

    2012-10-01

    Full Text Available Supplier selection is one of the most important decisions made in supply chain management. Supplier evaluation problem has been in the center of supply chain researcher’s attention in these years. Managers regard some of these studies and methods inappropriate due to simple, weight scoring methods that generally are based on subjective opinions and judgments of decision maker units involved in the supplier evaluation process yielding imprecise and even unreliable results. This paper seeks to propose a methodology to integrate data envelopment analysis (DEA and group analytical hierarchy process (GAHP for evaluating and selecting the most efficient supplier. We develop a methodology, which consists of 6 steps, one by one has been introduced in lecture and finally applicability of proposed method is indicated by assessing 12 suppliers in a numerical example.

  3. Variance reduction methods applied to deep-penetration problems

    International Nuclear Information System (INIS)

    Cramer, S.N.

    1984-01-01

    All deep-penetration Monte Carlo calculations require variance reduction methods. Before beginning with a detailed approach to these methods, several general comments concerning deep-penetration calculations by Monte Carlo, the associated variance reduction, and the similarities and differences of these with regard to non-deep-penetration problems will be addressed. The experienced practitioner of Monte Carlo methods will easily find exceptions to any of these generalities, but it is felt that these comments will aid the novice in understanding some of the basic ideas and nomenclature. Also, from a practical point of view, the discussions and developments presented are oriented toward use of the computer codes which are presented in segments of this Monte Carlo course

  4. Links between Alcohol and Other Drug Problems and Maltreatment among Adolescent Girls: Perceived Discrimination, Ethnic Identity, and Ethnic Orientation as Moderators

    Science.gov (United States)

    Gray, Calonie M. K.; Montgomery, Marilyn J.

    2012-01-01

    Objectives: This study examined the links between maltreatment, posttraumatic stress symptoms, ethnicity-specific factors (i.e., perceived discrimination, ethnic identity, and ethnic orientation), and alcohol and/or other drug (AOD) problems among adolescent girls. Methods: These relations were examined using archived data from a community sample…

  5. Group theoretic approach for solving the problem of diffusion of a drug through a thin membrane

    Science.gov (United States)

    Abd-El-Malek, Mina B.; Kassem, Magda M.; Meky, Mohammed L. M.

    2002-03-01

    The transformation group theoretic approach is applied to study the diffusion process of a drug through a skin-like membrane which tends to partially absorb the drug. Two cases are considered for the diffusion coefficient. The application of one parameter group reduces the number of independent variables by one, and consequently the partial differential equation governing the diffusion process with the boundary and initial conditions is transformed into an ordinary differential equation with the corresponding conditions. The obtained differential equation is solved numerically using the shooting method, and the results are illustrated graphically and in tables.

  6. Element Free Lattice Boltzmann Method for Fluid-Flow Problems

    International Nuclear Information System (INIS)

    Jo, Jong Chull; Roh, Kyung Wan; Yune, Young Gill; Kim, Hho Jhung; Kwon, Young Kwon

    2007-01-01

    The Lattice Boltzmann Method (LBM) has been developed for application to thermal-fluid problems. Most of the those studies considered a regular shape of lattice or mesh like square and cubic grids. In order to apply the LBM to more practical cases, it is necessary to be able to solve complex or irregular shapes of problem domains. Some techniques were based on the finite element method. Generally, the finite element method is very powerful for solving two or three-dimensional complex or irregular shapes of domains using the iso-parametric element formulation which is based on a mathematical mapping from a regular shape of element in an imaginary domain to a more general and irregular shape of element in the physical domain. In addition, the element free technique is also quite useful to analyze a complex shape of domain because there is no need to divide a domain by a compatible finite element mesh. This paper presents a new finite element and element free formulations for the lattice Boltzmann equation using the general weighted residual technique. Then, a series of validation examples are presented

  7. Element Free Lattice Boltzmann Method for Fluid-Flow Problems

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Roh, Kyung Wan; Yune, Young Gill; Kim, Hho Jhung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Kwon, Young Kwon [US Naval Postgraduate School, New York (United States)

    2007-10-15

    The Lattice Boltzmann Method (LBM) has been developed for application to thermal-fluid problems. Most of the those studies considered a regular shape of lattice or mesh like square and cubic grids. In order to apply the LBM to more practical cases, it is necessary to be able to solve complex or irregular shapes of problem domains. Some techniques were based on the finite element method. Generally, the finite element method is very powerful for solving two or three-dimensional complex or irregular shapes of domains using the iso-parametric element formulation which is based on a mathematical mapping from a regular shape of element in an imaginary domain to a more general and irregular shape of element in the physical domain. In addition, the element free technique is also quite useful to analyze a complex shape of domain because there is no need to divide a domain by a compatible finite element mesh. This paper presents a new finite element and element free formulations for the lattice Boltzmann equation using the general weighted residual technique. Then, a series of validation examples are presented.

  8. Global regularization method for planar restricted three-body problem

    Directory of Open Access Journals (Sweden)

    Sharaf M.A.

    2015-01-01

    Full Text Available In this paper, global regularization method for planar restricted three-body problem is purposed by using the transformation z = x+iy = ν cos n(u+iv, where i = √−1, 0 < ν ≤ 1 and n is a positive integer. The method is developed analytically and computationally. For the analytical developments, analytical solutions in power series of the pseudotime τ are obtained for positions and velocities (u, v, u', v' and (x, y, x˙, y˙ in both regularized and physical planes respectively, the physical time t is also obtained as power series in τ. Moreover, relations between the coefficients of the power series are obtained for two consequent values of n. Also, we developed analytical solutions in power series form for the inverse problem of finding τ in terms of t. As typical examples, three symbolic expressions for the coefficients of the power series were developed in terms of initial values. As to the computational developments, the global regularized equations of motion are developed together with their initial values in forms suitable for digital computations using any differential equations solver. On the other hand, for numerical evolutions of power series, an efficient method depending on the continued fraction theory is provided.

  9. Adaptive sampling method in deep-penetration particle transport problem

    International Nuclear Information System (INIS)

    Wang Ruihong; Ji Zhicheng; Pei Lucheng

    2012-01-01

    Deep-penetration problem has been one of the difficult problems in shielding calculation with Monte Carlo method for several decades. In this paper, a kind of particle transport random walking system under the emission point as a sampling station is built. Then, an adaptive sampling scheme is derived for better solution with the achieved information. The main advantage of the adaptive scheme is to choose the most suitable sampling number from the emission point station to obtain the minimum value of the total cost in the process of the random walk. Further, the related importance sampling method is introduced. Its main principle is to define the importance function due to the particle state and to ensure the sampling number of the emission particle is proportional to the importance function. The numerical results show that the adaptive scheme under the emission point as a station could overcome the difficulty of underestimation of the result in some degree, and the adaptive importance sampling method gets satisfied results as well. (authors)

  10. Nuclear data for specific problems. Part 1: Methods

    International Nuclear Information System (INIS)

    Leszczynski, Francisco

    1999-01-01

    The growing volume of basic nuclear data, methods and codes for processing these data, and the wide variety of problems where these data and codes are required, oblige to have an efficient system for managing all this information. In this work we present a new methodology for nuclear data processing, applied to neutron and photon transport calculations for specific problems. The base of the new methodology is the analysis of the requirements, following the chain: Problem-Components-Materials-Elements-Isotopes-Process-Tests-Final product (a library with processed data). This order is the inverse of the normal order followed up to date where, for performing a specific calculation, the first step is the choice of an existing data library for general purposes, without the previous steps of pre-processing data, and tests of the final library. Then, the used data are limited to the isotope content of this library, and the adaptation of material compositions and components to the data availability is necessary , performing finally the required calculations in a rather approximated form, depending on the available data. An interactive computer program for PC , is developed, for managing all the information generated by nuclear data processing, with the additional advantage of having a help tool for performing the needed analysis, before processing data calculations for specific applications. These analyses are based on the particular characteristics of each application, and the processed information of previous cases, is stored in conveniently designed data bases for an easy inspection of its contents. By means of an example of application of the new method, in this paper the methods of analysis and calculations and the tools used (computer programs, data bases and documents) are describes. (author)

  11. Finite element method for neutron diffusion problems in hexagonal geometry

    International Nuclear Information System (INIS)

    Wei, T.Y.C.; Hansen, K.F.

    1975-06-01

    The use of the finite element method for solving two-dimensional static neutron diffusion problems in hexagonal reactor configurations is considered. It is investigated as a possible alternative to the low-order finite difference method. Various piecewise polynomial spaces are examined for their use in hexagonal problems. The central questions which arise in the design of these spaces are the degree of incompleteness permissible and the advantages of using a low-order space fine-mesh approach over that of a high-order space coarse-mesh one. There is also the question of the degree of smoothness required. Two schemes for the construction of spaces are described and a number of specific spaces, constructed with the questions outlined above in mind, are presented. They range from a complete non-Lagrangian, non-Hermite quadratic space to an incomplete ninth order space. Results are presented for two-dimensional problems typical of a small high temperature gas-cooled reactor. From the results it is concluded that the space used should at least include the complete linear one. Complete spaces are to be preferred to totally incomplete ones. Once function continuity is imposed any additional degree of smoothness is of secondary importance. For flux shapes typical of the small high temperature gas-cooled reactor the linear space fine-mesh alternative is to be preferred to the perturbation quadratic space coarse-mesh one and the low-order finite difference method is to be preferred over both finite element schemes

  12. Comparing Methods for Estimating Direct Costs of Adverse Drug Events.

    Science.gov (United States)

    Gyllensten, Hanna; Jönsson, Anna K; Hakkarainen, Katja M; Svensson, Staffan; Hägg, Staffan; Rehnberg, Clas

    2017-12-01

    To estimate how direct health care costs resulting from adverse drug events (ADEs) and cost distribution are affected by methodological decisions regarding identification of ADEs, assigning relevant resource use to ADEs, and estimating costs for the assigned resources. ADEs were identified from medical records and diagnostic codes for a random sample of 4970 Swedish adults during a 3-month study period in 2008 and were assessed for causality. Results were compared for five cost evaluation methods, including different methods for identifying ADEs, assigning resource use to ADEs, and for estimating costs for the assigned resources (resource use method, proportion of registered cost method, unit cost method, diagnostic code method, and main diagnosis method). Different levels of causality for ADEs and ADEs' contribution to health care resource use were considered. Using the five methods, the maximum estimated overall direct health care costs resulting from ADEs ranged from Sk10,000 (Sk = Swedish krona; ~€1,500 in 2016 values) using the diagnostic code method to more than Sk3,000,000 (~€414,000) using the unit cost method in our study population. The most conservative definitions for ADEs' contribution to health care resource use and the causality of ADEs resulted in average costs per patient ranging from Sk0 using the diagnostic code method to Sk4066 (~€500) using the unit cost method. The estimated costs resulting from ADEs varied considerably depending on the methodological choices. The results indicate that costs for ADEs need to be identified through medical record review and by using detailed unit cost data. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  13. The shortest-path problem analysis and comparison of methods

    CERN Document Server

    Ortega-Arranz, Hector; Gonzalez-Escribano, Arturo

    2014-01-01

    Many applications in different domains need to calculate the shortest-path between two points in a graph. In this paper we describe this shortest path problem in detail, starting with the classic Dijkstra's algorithm and moving to more advanced solutions that are currently applied to road network routing, including the use of heuristics and precomputation techniques. Since several of these improvements involve subtle changes to the search space, it may be difficult to appreciate their benefits in terms of time or space requirements. To make methods more comprehensive and to facilitate their co

  14. Advances in industrial biopharmaceutical batch process monitoring: Machine-learning methods for small data problems.

    Science.gov (United States)

    Tulsyan, Aditya; Garvin, Christopher; Ündey, Cenk

    2018-04-06

    Biopharmaceutical manufacturing comprises of multiple distinct processing steps that require effective and efficient monitoring of many variables simultaneously in real-time. The state-of-the-art real-time multivariate statistical batch process monitoring (BPM) platforms have been in use in recent years to ensure comprehensive monitoring is in place as a complementary tool for continued process verification to detect weak signals. This article addresses a longstanding, industry-wide problem in BPM, referred to as the "Low-N" problem, wherein a product has a limited production history. The current best industrial practice to address the Low-N problem is to switch from a multivariate to a univariate BPM, until sufficient product history is available to build and deploy a multivariate BPM platform. Every batch run without a robust multivariate BPM platform poses risk of not detecting potential weak signals developing in the process that might have an impact on process and product performance. In this article, we propose an approach to solve the Low-N problem by generating an arbitrarily large number of in silico batches through a combination of hardware exploitation and machine-learning methods. To the best of authors' knowledge, this is the first article to provide a solution to the Low-N problem in biopharmaceutical manufacturing using machine-learning methods. Several industrial case studies from bulk drug substance manufacturing are presented to demonstrate the efficacy of the proposed approach for BPM under various Low-N scenarios. © 2018 Wiley Periodicals, Inc.

  15. The impact of drug policy liberalisation on willingness to seek help for problem drug use: A comparison of 20 countries.

    Science.gov (United States)

    Benfer, Isabella; Zahnow, Renee; Barratt, Monica J; Maier, Larissa; Winstock, Adam; Ferris, Jason

    2018-06-01

    While the impact of changing drug policies on rates of drug use has been investigated, research into how help-seeking behaviour changes as drug policies become more public-health focused is limited. This paper investigates reported changes in confidence to utilise drug services following hypothetical changes in national drug policy among a sample of individuals who report recent illicit drug use. We predict that liberalising national drug policy will increase the propensity for people who take illegal drugs to utilise health services. The data were drawn from a sample of self-reported responses to the 2014 Global Drug Survey. Respondents were asked if they would be more confident seeking help if each of the following policy changes were made in their country; a) drugs were legalised; b) penalties for possession of small amounts of drugs were reduced to a fine only; c) drugs were legally available through governments outlets. Multiple correspondence analysis and multinomial logistic regression with post-estimation linear hypothesis testing were conducted. Individuals residing in countries with relatively liberal drug policy regimes report their help-seeking behaviour is unlikely to change given the hypothetical policy amendments. Individuals from countries with prohibition-based drug policies reported a far greater propensity for changing their help-seeking behaviour in the event of hypothetical policy amendments, citing reduced fear of criminal sanctions as the major reason. Age and sex differences were also found. The current study demonstrates the capacity for national drug policy reform to influence drug use risk by facilitating or impeding health service engagement among individuals who use illicit substances. We suggest national drug policy requires careful consideration of both prevention goals and the needs of individuals already engaged in illicit substance use; more liberal drug policies may actually encourage the adoption of harm reduction strategies such

  16. The Relationship of Social Problem-Solving Skills and Dysfunctional Attitudes with Risk of Drug Abuse among Dormitory Students at Isfahan University of Medical Sciences.

    Science.gov (United States)

    Nasrazadani, Ehteram; Maghsoudi, Jahangir; Mahrabi, Tayebeh

    2017-01-01

    Dormitory students encounter multiple social factors which cause pressure, such as new social relationships, fear of the future, and separation from family, which could cause serious problems such as tendency toward drug abuse. This research was conducted with the goal to determine social problem-solving skills, dysfunctional attitudes, and risk of drug abuse among dormitory students of Isfahan University of Medical Sciences, Iran. This was a descriptive-analytical, correlational, and cross-sectional research. The research sample consisted of 211 students living in dormitories. The participants were selected using randomized quota sampling method. The data collection tools included the Social Problem-Solving Inventory (SPSI), Dysfunctional Attitude Scale (DAS), and Identifying People at Risk of Addiction Questionnaire. The results indicated an inverse relationship between social problem-solving skills and risk of drug abuse ( P = 0.0002), a direct relationship between dysfunctional attitude and risk of drug abuse ( P = 0.030), and an inverse relationship between social problem-solving skills and dysfunctional attitude among students ( P = 0.0004). Social problem-solving skills have a correlation with dysfunctional attitudes. As a result, teaching these skills and the way to create efficient attitudes should be considered in dormitory students.

  17. Comparison of optimal design methods in inverse problems

    International Nuclear Information System (INIS)

    Banks, H T; Holm, K; Kappel, F

    2011-01-01

    Typical optimal design methods for inverse or parameter estimation problems are designed to choose optimal sampling distributions through minimization of a specific cost function related to the resulting error in parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data collected according to the optimal sampling distribution. Here we formulate the classical optimal design problem in the context of general optimization problems over distributions of sampling times. We present a new Prohorov metric-based theoretical framework that permits one to treat succinctly and rigorously any optimal design criteria based on the Fisher information matrix. A fundamental approximation theory is also included in this framework. A new optimal design, SE-optimal design (standard error optimal design), is then introduced in the context of this framework. We compare this new design criterion with the more traditional D-optimal and E-optimal designs. The optimal sampling distributions from each design are used to compute and compare standard errors; the standard errors for parameters are computed using asymptotic theory or bootstrapping and the optimal mesh. We use three examples to illustrate ideas: the Verhulst–Pearl logistic population model (Banks H T and Tran H T 2009 Mathematical and Experimental Modeling of Physical and Biological Processes (Boca Raton, FL: Chapman and Hall/CRC)), the standard harmonic oscillator model (Banks H T and Tran H T 2009) and a popular glucose regulation model (Bergman R N, Ider Y Z, Bowden C R and Cobelli C 1979 Am. J. Physiol. 236 E667–77; De Gaetano A and Arino O 2000 J. Math. Biol. 40 136–68; Toffolo G, Bergman R N, Finegood D T, Bowden C R and Cobelli C 1980 Diabetes 29 979–90)

  18. Comparison of optimal design methods in inverse problems

    Science.gov (United States)

    Banks, H. T.; Holm, K.; Kappel, F.

    2011-07-01

    Typical optimal design methods for inverse or parameter estimation problems are designed to choose optimal sampling distributions through minimization of a specific cost function related to the resulting error in parameter estimates. It is hoped that the inverse problem will produce parameter estimates with increased accuracy using data collected according to the optimal sampling distribution. Here we formulate the classical optimal design problem in the context of general optimization problems over distributions of sampling times. We present a new Prohorov metric-based theoretical framework that permits one to treat succinctly and rigorously any optimal design criteria based on the Fisher information matrix. A fundamental approximation theory is also included in this framework. A new optimal design, SE-optimal design (standard error optimal design), is then introduced in the context of this framework. We compare this new design criterion with the more traditional D-optimal and E-optimal designs. The optimal sampling distributions from each design are used to compute and compare standard errors; the standard errors for parameters are computed using asymptotic theory or bootstrapping and the optimal mesh. We use three examples to illustrate ideas: the Verhulst-Pearl logistic population model (Banks H T and Tran H T 2009 Mathematical and Experimental Modeling of Physical and Biological Processes (Boca Raton, FL: Chapman and Hall/CRC)), the standard harmonic oscillator model (Banks H T and Tran H T 2009) and a popular glucose regulation model (Bergman R N, Ider Y Z, Bowden C R and Cobelli C 1979 Am. J. Physiol. 236 E667-77 De Gaetano A and Arino O 2000 J. Math. Biol. 40 136-68 Toffolo G, Bergman R N, Finegood D T, Bowden C R and Cobelli C 1980 Diabetes 29 979-90).

  19. Direct sampling methods for inverse elastic scattering problems

    Science.gov (United States)

    Ji, Xia; Liu, Xiaodong; Xi, Yingxia

    2018-03-01

    We consider the inverse elastic scattering of incident plane compressional and shear waves from the knowledge of the far field patterns. Specifically, three direct sampling methods for location and shape reconstruction are proposed using the different component of the far field patterns. Only inner products are involved in the computation, thus the novel sampling methods are very simple and fast to be implemented. With the help of the factorization of the far field operator, we give a lower bound of the proposed indicator functionals for sampling points inside the scatterers. While for the sampling points outside the scatterers, we show that the indicator functionals decay like the Bessel functions as the sampling point goes away from the boundary of the scatterers. We also show that the proposed indicator functionals continuously dependent on the far field patterns, which further implies that the novel sampling methods are extremely stable with respect to data error. For the case when the observation directions are restricted into the limited aperture, we firstly introduce some data retrieval techniques to obtain those data that can not be measured directly and then use the proposed direct sampling methods for location and shape reconstructions. Finally, some numerical simulations in two dimensions are conducted with noisy data, and the results further verify the effectiveness and robustness of the proposed sampling methods, even for multiple multiscale cases and limited-aperture problems.

  20. Influence of gender and race/ethnicity on perceived barriers to help-seeking for alcohol or drug problems.

    Science.gov (United States)

    Verissimo, Angie Denisse Otiniano; Grella, Christine E

    2017-04-01

    This study examines reasons why people do not seek help for alcohol or drug problems by gender and race/ethnicity using data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a nationally representative survey. Multivariate models were fit for 3 barriers to seeking help (structural, attitudinal, and readiness for change) for either alcohol or drug problems, controlling for socio-demographic characteristics and problem severity. Predicted probabilities were generated to evaluate gender differences by racial/ethnic subgroups. Over three quarters of the samples endorsed attitudinal barriers related to either alcohol or drug use. Generally, women were less likely to endorse attitudinal barriers for alcohol problems. African Americans and Latina/os were less likely than Whites to endorse attitudinal barriers for alcohol problems, Latina/os were less likely than Whites to endorse readiness for change barriers for alcohol and drug problems, however, African Americans were more likely to endorse structural barriers for alcohol problems. Comparisons within racial/ethnic subgroups by gender revealed more complex findings, although across all racial/ethnic groups women endorsed attitudinal barriers for alcohol problems more than men. Study findings suggest the need to tailor interventions to increase access to help for alcohol and drug problems that take into consideration both attitudinal and structural barriers and how these vary across groups. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. THE CONTROL VARIATIONAL METHOD FOR ELASTIC CONTACT PROBLEMS

    Directory of Open Access Journals (Sweden)

    Mircea Sofonea

    2010-07-01

    Full Text Available We consider a multivalued equation of the form Ay + F(y = fin a real Hilbert space, where A is a linear operator and F represents the (Clarke subdifferential of some function. We prove existence and uniqueness results of the solution by using the control variational method. The main idea in this method is to minimize the energy functional associated to the nonlinear equation by arguments of optimal control theory. Then we consider a general mathematical model describing the contact between a linearly elastic body and an obstacle which leads to a variational formulation as above, for the displacement field. We apply the abstract existence and uniqueness results to prove the unique weak solvability of the corresponding contact problem. Finally, we present examples of contact and friction laws for which our results work.

  2. Lavrentiev regularization method for nonlinear ill-posed problems

    International Nuclear Information System (INIS)

    Kinh, Nguyen Van

    2002-10-01

    In this paper we shall be concerned with Lavientiev regularization method to reconstruct solutions x 0 of non ill-posed problems F(x)=y o , where instead of y 0 noisy data y δ is an element of X with absolut(y δ -y 0 ) ≤ δ are given and F:X→X is an accretive nonlinear operator from a real reflexive Banach space X into itself. In this regularization method solutions x α δ are obtained by solving the singularly perturbed nonlinear operator equation F(x)+α(x-x*)=y δ with some initial guess x*. Assuming certain conditions concerning the operator F and the smoothness of the element x*-x 0 we derive stability estimates which show that the accuracy of the regularized solutions is order optimal provided that the regularization parameter α has been chosen properly. (author)

  3. Probabilist methods applied to electric source problems in nuclear safety

    International Nuclear Information System (INIS)

    Carnino, A.; Llory, M.

    1979-01-01

    Nuclear Safety has frequently been asked to quantify safety margins and evaluate the hazard. In order to do so, the probabilist methods have proved to be the most promising. Without completely replacing determinist safety, they are now commonly used at the reliability or availability stages of systems as well as for determining the likely accidental sequences. In this paper an application linked to the problem of electric sources is described, whilst at the same time indicating the methods used. This is the calculation of the probable loss of all the electric sources of a pressurized water nuclear power station, the evaluation of the reliability of diesels by event trees of failures and the determination of accidental sequences which could be brought about by the 'total electric source loss' initiator and affect the installation or the environment [fr

  4. Monte Carlo methods for flux expansion solutions of transport problems

    International Nuclear Information System (INIS)

    Spanier, J.

    1999-01-01

    Adaptive Monte Carlo methods, based on the use of either correlated sampling or importance sampling, to obtain global solutions to certain transport problems have recently been described. The resulting learning algorithms are capable of achieving geometric convergence when applied to the estimation of a finite number of coefficients in a flux expansion representation of the global solution. However, because of the nonphysical nature of the random walk simulations needed to perform importance sampling, conventional transport estimators and source sampling techniques require modification to be used successfully in conjunction with such flux expansion methods. It is shown how these problems can be overcome. First, the traditional path length estimators in wide use in particle transport simulations are generalized to include rather general detector functions (which, in this application, are the individual basis functions chosen for the flus expansion). Second, it is shown how to sample from the signed probabilities that arise as source density functions in these applications, without destroying the zero variance property needed to ensure geometric convergence to zero error

  5. A method for unbalanced transportation problems in fuzzy ...

    Indian Academy of Sciences (India)

    Among linear programming problems, the transportation problem is very popular. ... Therefore, Zadeh (1965) introduced the concept of fuzzy numbers. ... While solving unbalanced transportation problems we come across two type of cases.

  6. Ophthalmic Drug Dosage Forms: Characterisation and Research Methods

    OpenAIRE

    Baranowski, Przemysław; Karolewicz, Bożena; Gajda, Maciej; Pluta, Janusz

    2014-01-01

    This paper describes hitherto developed drug forms for topical ocular administration, that is, eye drops, ointments, in situ gels, inserts, multicompartment drug delivery systems, and ophthalmic drug forms with bioadhesive properties. Heretofore, many studies have demonstrated that new and more complex ophthalmic drug forms exhibit advantage over traditional ones and are able to increase the bioavailability of the active substance by, among others, reducing the susceptibility of drug forms to...

  7. Condensed history Monte Carlo methods for photon transport problems

    International Nuclear Information System (INIS)

    Bhan, Katherine; Spanier, Jerome

    2007-01-01

    We study methods for accelerating Monte Carlo simulations that retain most of the accuracy of conventional Monte Carlo algorithms. These methods - called Condensed History (CH) methods - have been very successfully used to model the transport of ionizing radiation in turbid systems. Our primary objective is to determine whether or not such methods might apply equally well to the transport of photons in biological tissue. In an attempt to unify the derivations, we invoke results obtained first by Lewis, Goudsmit and Saunderson and later improved by Larsen and Tolar. We outline how two of the most promising of the CH models - one based on satisfying certain similarity relations and the second making use of a scattering phase function that permits only discrete directional changes - can be developed using these approaches. The main idea is to exploit the connection between the space-angle moments of the radiance and the angular moments of the scattering phase function. We compare the results obtained when the two CH models studied are used to simulate an idealized tissue transport problem. The numerical results support our findings based on the theoretical derivations and suggest that CH models should play a useful role in modeling light-tissue interactions

  8. Using the PROSA Method in Offshore Wind Farm Location Problems

    Directory of Open Access Journals (Sweden)

    Paweł Ziemba

    2017-11-01

    Full Text Available Wind is the most used renewable energy source (RES in the European Union and Poland. Due to the legal changes in the scope of RES in Poland, there are plans to develop offshore wind farms at the expense of onshore ones. On the other hand, the success of an offshore wind farm is primarily determined by its location. Therefore, the aim of this study is to select offshore wind farm locations in Poland, based on sustainability assessment, which is an inherent aspect of RES decision-making issues. To accomplish the objectives of this research, PROSA (PROMETHEE for Sustainability Assessment method, a new multi-criteria method is proposed. Like PROMETHEE (Preference Ranking Organization METHod for Enrichment Evaluation, PROSA is transparent for decision makers and is easy to use; moreover, it provides the analytical tools available in PROMETHEE, i.e., the sensitivity and GAIA (Geometrical Analysis for Interactive Assistance analyses. However, PROSA is characterized by a lower degree of criteria compensation than PROMETHEE. Thus, it adheres in a higher degree to the strong sustainability paradigm. The study also compared the solutions of the decision problem obtained with the use of PROSA and PROMETHEE methods. The compared methods demonstrated a high concurrence of the recommended decision-making variant of location selection, from methodological and practical points of view. At the same time, the conducted research allowed to confirm that the PROSA method recommends more sustainable decision-making variants, and that the ranking it builds is less sensitive to changes in criteria weights. Therefore, it is more stable than the PROMETHEE-based ranking.

  9. [Alcohol and drugs in Central Europe--problems and possible solutions].

    Science.gov (United States)

    Nespor, K; Cs emy, L

    1994-08-22

    The high alcohol consumption and increasing abuse of other addictive inducing substances in Central Europe calls for broadley conceived preventive programmes and cheap and widely applicable therapeutic strategies (early treatment at the first contact level, self-help manuals, self-aid organizations). Social instability along with greater availability of alcohol and drugs create a dangerous combination. In addition to strategies of stress prevention at the societal level also strategy at the individual level is important (e.g. relaxation training, yoga, psychotherapy). It is also important to change the "image" of western society and commercial interests of those who make profits on alcohol and drugs should be under control and advertising should be greatly restricted if not prohibited. Prevention of problems caused by alcohol and drugs in particular in youths must be combined and really effective strategies should be used such as peer programmes. The authors mention also their own preventive programme FIT IN and print materials oriented specifically on certain population groups.

  10. Admissions through the emergency department due to drug-related problems

    International Nuclear Information System (INIS)

    Yosef H Al-Olah; Khalifa M Al Thiab

    2010-01-01

    Hospital admissions due to drug-related problems (DRPs) have been studied internationally, but local data are limited. Therefore, we undertook a prospective, observational study of all admissions through the emergency department (ED) at a tertiary referral hospital in Saudi Arabia to determine the incidence of admissions through the ED due to DRPs, types of DRPs, length of stay (LOS) in the hospital after ED admissions due to DRPs, and assessment of preventability of admissions due to DRPs.All admissions through the ED over a period of 28 consecutive days were evaluated to determine if they were due to definite or possible DRPs. Data was collected on a daily basis for each admission over the previous 24 hours. Each incident was assessed by three investigators Of 557 patients admitted through the ED, 82 (14.7%) admissions were due to DRP (53 definite, 29 possible). The most common types of DRP were failure to receive medication in 25 cases (47.2%), an adverse drug reaction in 13 cases (24.5%), and drug overdose in 6 cases (11.3%). In the definite DRP group, 83.0% were definitely preventable, 3.8% were possibly preventable and 13.2% were definitely non-preventable.DRPs are a serious and costly issue facing health care professionals and health care systems. Most admissions due to DRPs are avoidable (Author).

  11. Engendering drug problems: Materialising gender in the DUDIT and other screening and diagnostic 'apparatuses'.

    Science.gov (United States)

    Dwyer, Robyn; Fraser, Suzanne

    2017-06-01

    It is widely accepted that alcohol and other drug consumption is profoundly gendered. Just where this gendering is occurring, however, remains the subject of debate. We contend that one important and overlooked site where the gendering of substance consumption and addiction is taking place is through AOD research itself: in particular, through the addiction screening and diagnostic tools designed to measure and track substance consumption and problems within populations. These tools establish key criteria and set numerical threshold scores for the identification of problems. In many of these tools, separate threshold scores for women and men are established or recommended. Drawing on Karen Barad's concept of post-humanist performativity, in this article we examine the ways in which gender itself is being materialised by these apparatuses of measurement. We focus primarily on the Drug Use Disorders Identification Test (DUDIT) tool as an exemplar of gendering processes that operate across addiction tools more broadly. We consider gendering processes operating through tools questions themselves and we also examine the quantification and legitimation processes used in establishing gender difference and the implications these have for women. We find tools rely on and reproduce narrow and marginalising assumptions about women as essentially fragile and vulnerable and simultaneously reinforce normative expectations that women sacrifice pleasure. The seemingly objective and neutral quantification processes operating in tools naturalise gender as they enact it. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. A New Method Based on TOPSIS and Response Surface Method for MCDM Problems with Interval Numbers

    Directory of Open Access Journals (Sweden)

    Peng Wang

    2015-01-01

    Full Text Available As the preference of design maker (DM is always ambiguous, we have to face many multiple criteria decision-making (MCDM problems with interval numbers in our daily life. Though there have been some methods applied to solve this sort of problem, it is always complex to comprehend and sometimes difficult to implement. The calculation processes are always ineffective when a new alternative is added or removed. In view of the weakness like this, this paper presents a new method based on TOPSIS and response surface method (RSM for MCDM problems with interval numbers, RSM-TOPSIS-IN for short. The key point of this approach is the application of deviation degree matrix, which ensures that the DM can get a simple response surface (RS model to rank the alternatives. In order to demonstrate the feasibility and effectiveness of the proposed method, three illustrative MCMD problems with interval numbers are analysed, including (a selection of investment program, (b selection of a right partner, and (c assessment of road transport technologies. The contrast of ranking results shows that the RSM-TOPSIS-IN method is in good agreement with those derived by earlier researchers, indicating it is suitable to solve MCDM problems with interval numbers.

  13. Ophthalmic Drug Dosage Forms: Characterisation and Research Methods

    Directory of Open Access Journals (Sweden)

    Przemysław Baranowski

    2014-01-01

    Full Text Available This paper describes hitherto developed drug forms for topical ocular administration, that is, eye drops, ointments, in situ gels, inserts, multicompartment drug delivery systems, and ophthalmic drug forms with bioadhesive properties. Heretofore, many studies have demonstrated that new and more complex ophthalmic drug forms exhibit advantage over traditional ones and are able to increase the bioavailability of the active substance by, among others, reducing the susceptibility of drug forms to defense mechanisms of the human eye, extending contact time of drug with the cornea, increasing the penetration through the complex anatomical structure of the eye, and providing controlled release of drugs into the eye tissues, which allows reducing the drug application frequency. The rest of the paper describes recommended in vitro and in vivo studies to be performed for various ophthalmic drugs forms in order to assess whether the form is acceptable from the perspective of desired properties and patient’s compliance.

  14. Enhanced exact solution methods for the Team Orienteering Problem

    NARCIS (Netherlands)

    Keshtkaran, M.; Ziarati, K.; Bettinelli, A.; Vigo, D.

    2016-01-01

    The Team Orienteering Problem (TOP) is one of the most investigated problems in the family of vehicle routing problems with profits. In this paper, we propose a Branch-and-Price approach to find proven optimal solutions to TOP. The pricing sub-problem is solved by a bounded bidirectional dynamic

  15. Introduction to the College on Problems of Drug Dependence special issue: contemporary advances in opioid neuropharmacology.

    Science.gov (United States)

    Walsh, Sharon L; Unterwald, Ellen M; Izenwasser, Sari

    2010-05-01

    Opioid receptors are critical therapeutic targets for medications development relevant to the treatment of drug dependence and pain. With recent advances in molecular neurobiology, it has become evident that the functional activity of opioid receptors, as ligand-regulated protein complexes, is modulated by multifarious intracellular and extracellular events, that there is genetic variation in coding for receptors, and that the activity of endogenous opioid systems may underlie actions common to other addictive disorders. This supplemental issue of Drug and Alcohol Dependence, arising from an invited symposium at the 71st Annual Meeting of the College on Problems of Drug Dependence, provides a series of contemporary reviews focused on recent advances in opioid neuropharmacology. Each speaker provides herein an invited comprehensive review of the state of knowledge on a specific topic in opioid neuropharmacology. Evans and colleagues describe the multi-faceted control of the opioid G-protein coupled receptor as a dynamic "sensor" complex and identify novel targets for drug development. von Zastrow focuses on opioid receptor-mediated events regulated by endocytosis and membrane trafficking through the endocytic pathway and differential responses to opioid agonists. Blendy and colleague provide a review of human association studies on the functional relevance of the mu opioid receptor variant, A118G, and presents data from the A112G knock-in model, an analogous mouse variant to A118G. Finally, Maldonado and colleagues provide a broader systems review from genetic, pharmacologic and behavioral studies implicating the endogenous opioid systems as a substrate for the mediation of substance use disorders spanning pharmacological classes.

  16. Solving some problems of engineering seismology by structural method

    International Nuclear Information System (INIS)

    Ishtev, K.G.; Hadjikov, L.M.; Dineva, P.S.; Jordanov, P.P.

    1983-01-01

    The work suggests a method for solving the direct and inverse problems of the engineer seismology by means of the structural approach of the systems theory. This approach gives a possibility for a simultaneous accounting of the two basic types of damping of the seismic signals in the earth foundation-geometrical damping and a damping in consequence of a dissipative energy loss. By the structural scheme an automatic account is made of the geometric damping of the signals. The damping from a dissipative energy loss on the other hand is accounted for through a choice of the type of frequency characteristics or the transmission functions of the different layers. With a few examples the advantages of the model including the two types of attenuation of the seismic signal are illustrated. An integral coefficient of damping is calculated which analogously to the frequency functions represents a generalized characteristic of is the whole earth foundation. (orig./HP)

  17. Manufacturing Data Uncertainties Propagation Method in Burn-Up Problems

    Directory of Open Access Journals (Sweden)

    Thomas Frosio

    2017-01-01

    Full Text Available A nuclear data-based uncertainty propagation methodology is extended to enable propagation of manufacturing/technological data (TD uncertainties in a burn-up calculation problem, taking into account correlation terms between Boltzmann and Bateman terms. The methodology is applied to reactivity and power distributions in a Material Testing Reactor benchmark. Due to the inherent statistical behavior of manufacturing tolerances, Monte Carlo sampling method is used for determining output perturbations on integral quantities. A global sensitivity analysis (GSA is performed for each manufacturing parameter and allows identifying and ranking the influential parameters whose tolerances need to be better controlled. We show that the overall impact of some TD uncertainties, such as uranium enrichment, or fuel plate thickness, on the reactivity is negligible because the different core areas induce compensating effects on the global quantity. However, local quantities, such as power distributions, are strongly impacted by TD uncertainty propagations. For isotopic concentrations, no clear trends appear on the results.

  18. IDENTIFIKASI DRUG RELATED PROBLEMs (DRPs PADA PASIEN PEDIATRI PNEUMONIA KOMUNITAS DI INSTALASI RAWAT INAP RSD MADANI PROVINSI SULAWESI TENGAH

    Directory of Open Access Journals (Sweden)

    Putu Maharani Ajeng Astiti

    2017-03-01

    Full Text Available Drug Related Problems (DRPs are events or circumstances involving drug therapy that actually or potentially interfere with desired health outcomes. DRPs may occur in the treatment of various diseases such as community acquired pneumonia (CAP. This study aims to determine the percentage of DRPs in pediatric inpatients with CAP. This is a descriptive and observational study design with prospective data conducted in November 2015 until February 2016 at Madani Hospital, Central Sulawesi. The results obtained from 28 patients showed that incidences of DRPs categories of inappropriate drug is 1 event (1,7%, inappropriate drug combination 35 events (58,3%, drugs dose too low 18 events (30%, drugs dose too high  6 events (10%, and no indication for drug 0 event (0%.

  19. Individualized drug dosing using RBF-Galerkin method: Case of anemia management in chronic kidney disease.

    Science.gov (United States)

    Mirinejad, Hossein; Gaweda, Adam E; Brier, Michael E; Zurada, Jacek M; Inanc, Tamer

    2017-09-01

    Anemia is a common comorbidity in patients with chronic kidney disease (CKD) and is frequently associated with decreased physical component of quality of life, as well as adverse cardiovascular events. Current treatment methods for renal anemia are mostly population-based approaches treating individual patients with a one-size-fits-all model. However, FDA recommendations stipulate individualized anemia treatment with precise control of the hemoglobin concentration and minimal drug utilization. In accordance with these recommendations, this work presents an individualized drug dosing approach to anemia management by leveraging the theory of optimal control. A Multiple Receding Horizon Control (MRHC) approach based on the RBF-Galerkin optimization method is proposed for individualized anemia management in CKD patients. Recently developed by the authors, the RBF-Galerkin method uses the radial basis function approximation along with the Galerkin error projection to solve constrained optimal control problems numerically. The proposed approach is applied to generate optimal dosing recommendations for individual patients. Performance of the proposed approach (MRHC) is compared in silico to that of a population-based anemia management protocol and an individualized multiple model predictive control method for two case scenarios: hemoglobin measurement with and without observational errors. In silico comparison indicates that hemoglobin concentration with MRHC method has less variation among the methods, especially in presence of measurement errors. In addition, the average achieved hemoglobin level from the MRHC is significantly closer to the target hemoglobin than that of the other two methods, according to the analysis of variance (ANOVA) statistical test. Furthermore, drug dosages recommended by the MRHC are more stable and accurate and reach the steady-state value notably faster than those generated by the other two methods. The proposed method is highly efficient for

  20. hp Spectral element methods for three dimensional elliptic problems

    Indian Academy of Sciences (India)

    elliptic boundary value problems on non-smooth domains in R3. For Dirichlet problems, ... of variable degree bounded by W. Let N denote the number of layers in the geomet- ric mesh ... We prove a stability theorem for mixed problems when the spectral element functions vanish ..... Applying Theorem 3.1,. ∫ r l. |Mu|2dx −.

  1. A Quantitative Method for Localizing User Interface Problems: The D-TEO Method

    Directory of Open Access Journals (Sweden)

    Juha Lamminen

    2009-01-01

    Full Text Available A large array of evaluation methods have been proposed to identify Website usability problems. In log-based evaluation, information about the performance of users is collected and stored into log files, and used to find problems and deficiencies in Web page designs. Most methods require the programming and modeling of large task models, which are cumbersome processes for evaluators. Also, because much statistical data is collected onto log files, recognizing which Web pages require deeper usability analysis is difficult. This paper suggests a novel quantitative method, called the D-TEO, for locating problematic Web pages. This semiautomated method explores the decomposition of interaction tasks of directed information search into elementary operations, deploying two quantitative usability criteria, search success and search time, to reveal how a user navigates within a web of hypertext.

  2. Beating camp addiction: Drug use in the camps is a problem, but former addicts prove the habit can be broken.

    Energy Technology Data Exchange (ETDEWEB)

    Ball, C.

    2004-12-06

    Drug dependency among personnel in the oil industry, and the measures taken by industry trying to cope with it, are discussed. Because drug users are five times more likely to be in an accident, many companies have instituted regular drug testing programs. Such programs are considered to be particularly effective when combined with a program designed to educate personnel, but also managers and supervisors of the dangers of drug use and best practices to deal with them. It should be noted that firing an employee found to be using drugs is not a solution since drug dependency is considered to be a disability under the Human Rights Code, and employers are not allowed to discriminate against someone with a disability. The policy followed by most employers is immediate suspension upon discovery of drug use, followed by intensive supportive treatment, aimed at getting the individual to address his addiction, and putting him back to work as soon as it is deemed safe to do so. Wherever possible, voluntary admission of having a drug problem, and an enlightened, sincere effort to treat the problem as a disease in a non-judgmental way, is considered far superior to programs relying chiefly on drug testing.

  3. A national drug related problems database: evaluation of use in practice, reliability and reproducibility

    DEFF Research Database (Denmark)

    Kjeldsen, Lene Juel; Birkholm, Trine; Fischer, Hanne Lis

    2014-01-01

    Background A drug related problems database (DRP-database) was developed on request by clinical pharmacists. The information from the DRP-database has only been used locally e.g. to identify focus areas and to communicate identified DRPs to the hospital wards. Hence the quality of the data...... by clinical pharmacists with categorization performed by the project group. Reproducibility was explored by re-categorization of a sample of existing records in the DRP-database by two project group members individually. Main outcome measures Observed proportion of agreement and Fleiss' kappa as measures...... reliability study of 34 clinical pharmacists showed high inter-rater reliability with the project group (Fleiss' kappa = 0.79 with 95 % CI (0.70; 0.88)), and the reproducibility study also documented high inter-rater reliability of a sample of 379 records from the DRP-database re-categorized by two project...

  4. Unilateral contact problems variational methods and existence theorems

    CERN Document Server

    Eck, Christof; Krbec, Miroslav

    2005-01-01

    The mathematical analysis of contact problems, with or without friction, is an area where progress depends heavily on the integration of pure and applied mathematics. This book presents the state of the art in the mathematical analysis of unilateral contact problems with friction, along with a major part of the analysis of dynamic contact problems without friction. Much of this monograph emerged from the authors'' research activities over the past 10 years and deals with an approach proven fruitful in many situations. Starting from thin estimates of possible solutions, this approach is based on an approximation of the problem and the proof of a moderate partial regularity of the solution to the approximate problem. This in turn makes use of the shift (or translation) technique - an important yet often overlooked tool for contact problems and other nonlinear problems with limited regularity. The authors pay careful attention to quantification and precise results to get optimal bounds in sufficient conditions f...

  5. Online and Mobile Interventions for Problem Gambling, Alcohol, and Drugs: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Isabelle Giroux

    2017-06-01

    Full Text Available Online interventions for gambling, alcohol, and illegal drug related problems have been developing at a fast pace over the past decade. Yet, little is known about the content and efficacy of interventions provided entirely online for reducing drug/alcohol use and gambling, or about the characteristics of those who use these interventions. This systematic review aims to describe the characteristics of online interventions, their efficacy, and the profile of their clientele. Documentation was mainly obtained through four scientific databases in psychology, technology, and medical research (PsychINFO, MedLine, Francis, and INSPEC using three keywords (substances or gambling, intervention, Internet. Of the 4,708 documents initially identified, 18 studies meeting admissibility criteria were retained and analyzed after exclusion of duplicates and non-relevant documents. No study in the review related to problem gambling. The majority of interventions were based upon motivational or cognitive-behavioral theoretical approaches and called upon well-established therapeutic components in the field of addictions. The participants in these studies were generally adults between 30 and 46 years old with a high school education and presenting a high risk or problematic use. More than three quarters of the studies showed a short-term decrease in use that was maintained 6 months later, but only two studies included a 12 months follow-up. Online interventions seem promising and appear to meet the needs of participants who are in the workforce and seeking help for the first time. Long-term efficacy studies should nonetheless be conducted.

  6. Online and Mobile Interventions for Problem Gambling, Alcohol, and Drugs: A Systematic Review.

    Science.gov (United States)

    Giroux, Isabelle; Goulet, Annie; Mercier, Jonathan; Jacques, Christian; Bouchard, Stéphane

    2017-01-01

    Online interventions for gambling, alcohol, and illegal drug related problems have been developing at a fast pace over the past decade. Yet, little is known about the content and efficacy of interventions provided entirely online for reducing drug/alcohol use and gambling, or about the characteristics of those who use these interventions. This systematic review aims to describe the characteristics of online interventions, their efficacy, and the profile of their clientele. Documentation was mainly obtained through four scientific databases in psychology, technology, and medical research (PsychINFO, MedLine, Francis, and INSPEC) using three keywords (substances or gambling, intervention, Internet). Of the 4,708 documents initially identified, 18 studies meeting admissibility criteria were retained and analyzed after exclusion of duplicates and non-relevant documents. No study in the review related to problem gambling. The majority of interventions were based upon motivational or cognitive-behavioral theoretical approaches and called upon well-established therapeutic components in the field of addictions. The participants in these studies were generally adults between 30 and 46 years old with a high school education and presenting a high risk or problematic use. More than three quarters of the studies showed a short-term decrease in use that was maintained 6 months later, but only two studies included a 12 months follow-up. Online interventions seem promising and appear to meet the needs of participants who are in the workforce and seeking help for the first time. Long-term efficacy studies should nonetheless be conducted.

  7. Grafting amino drugs to poly(styrene-alt-maleic anhydride) as a potential method for drug release

    Energy Technology Data Exchange (ETDEWEB)

    Khazaei, Ardeshir; Saednia, Shahnaz; Saien, Javad; Abbasi, Fatemeh, E-mail: Khazaei_1326@yahoo.com, E-mail: ssaednia@gmail.com [Faculty of Chemistry, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Kazem-Rostami, Masoud [Young Researchers Club and Elite, Takestan Branch, Islamic Azad University, Takestan (Iran, Islamic Republic of); Sadeghpour, Mahdieh [Department of Chemistry, Takestan Branch, Islamic Azad University, Takestan (Iran, Islamic Republic of); Borazjani, Maryam Kiani [Faculty of Science, Department of Chemistry, Bushehr Payame Noor University (PNU), Bushehr (Iran, Islamic Republic of)

    2013-07-15

    Drug delivery systems based on polymer-drug conjugates give an improved treatment with lower toxicity or side effects and be used for the treatment of different diseases. Conjugates of biodegradable poly(styrene-alt-maleic anhydride) (PSMA), with a therapeutic agents such as amantadine hydrochloride, amlodipine, gabapentin, zonisamide and mesalamine, were afforded by the formation of the amide bonds of the amino drugs that reacted with the PSMA anhydride groups. The amounts of covalently conjugated drugs were determined by a {sup 1}H NMR spectroscopic method, and the in vitro release rate in buffer solution (pH 1.3) was studied at body temperature 37 Degree-Sign C. In kinetic studies, different dissolution models were examined to obtain drug release data and the collected data were well-fitted to the Korsmeyer-Peppas equation, revealing a dominant Fickian diffusion mechanism for drug release under the in vitro conditions. (author)

  8. Assay method for organic calcium antagonist drugs and a kit for such an assay

    International Nuclear Information System (INIS)

    Snyder, S. H.; Gould, R. J.

    1985-01-01

    A method for measuring the level of organic calcium antagonist drug in a body fluid comprises preparing a mixture of a radioactive calcium antagonist drug, a body fluid containing a calcium antagonist drug and a calcium antagonist receptor material, measuring the radioactivity of the radioactive calcium antagonist drug bound to said calcium antagonist receptor material and deriving the concentration of the calcium antagonist drug in the body fluid from a standard curve indicating the concentration of calcium antagonist drug versus inhibition of binding of said radioactive calcium antagonist drug to said receptor sites caused by the calcium antagonist drug in said body fluid. A kit for measuring the level of an organic calcium drug comprises a receptacle containing a radioactive calcium antagonist drug, a calcium antagonist receptor material and a standard amount of a nonradioactive calcium antagonist drug

  9. Using standardized methods for research on HIV and injecting drug use in developing/transitional countries: case study from the WHO Drug Injection Study Phase II

    Directory of Open Access Journals (Sweden)

    Stimson Gerry V

    2006-03-01

    Full Text Available Abstract Background Successful cross-national research requires methods that are both standardized across sites and adaptable to local conditions. We report on the development and implementation of the methodology underlying the survey component of the WHO Drug Injection Study Phase II – a multi-site study of risk behavior and HIV seroprevalence among Injecting Drug Users (IDUs. Methods Standardized operational guidelines were developed by the Survey Coordinating Center in collaboration with the WHO Project Officer and participating site Investigators. Throughout the duration of the study, survey implementation at the local level was monitored by the Coordinating Center. Surveys were conducted in 12 different cities. Prior rapid assessment conducted in 10 cities provided insight into local context and guided survey implementation. Where possible, subjects were recruited both from drug abuse treatment centers and via street outreach. While emphasis was on IDUs, non-injectors were also recruited in cities with substantial non-injecting use of injectable drugs. A structured interview and HIV counseling/testing were administered. Results Over 5,000 subjects were recruited. Subjects were recruited from both drug treatment and street outreach in 10 cities. Non-injectors were recruited in nine cities. Prior rapid assessment identified suitable recruitment areas, reduced drug users' distrust of survey staff, and revealed site-specific risk behaviors. Centralized survey coordination facilitated local questionnaire modification within a core structure, standardized data collection protocols, uniform database structure, and cross-site analyses. Major site-specific problems included: questionnaire translation difficulties; locating affordable HIV-testing facilities; recruitment from drug treatment due to limited/selective treatment infrastructure; access to specific sub-groups of drug users in the community, particularly females or higher income groups

  10. Effect of Drug Loading Method and Drug Physicochemical Properties on the Material and Drug Release Properties of Poly (Ethylene Oxide Hydrogels for Transdermal Delivery

    Directory of Open Access Journals (Sweden)

    Rachel Shet Hui Wong

    2017-07-01

    Full Text Available Novel poly (ethylene oxide (PEO hydrogel films were synthesized via UV cross-linking with pentaerythritol tetra-acrylate (PETRA as cross-linking agent. The purpose of this work was to develop a novel hydrogel film suitable for passive transdermal drug delivery via skin application. Hydrogels were loaded with model drugs (lidocaine hydrochloride (LID, diclofenac sodium (DIC and ibuprofen (IBU via post-loading and in situ loading methods. The effect of loading method and drug physicochemical properties on the material and drug release properties of medicated film samples were characterized using scanning electron microscopy (SEM, swelling studies, differential scanning calorimetry (DSC, fourier transform infrared spectroscopy (FT-IR, tensile testing, rheometry, and drug release studies. In situ loaded films showed better drug entrapment within the hydrogel network and also better polymer crystallinity. High drug release was observed from all studied formulations. In situ loaded LID had a plasticizing effect on PEO hydrogel, and films showed excellent mechanical properties and prolonged drug release. The drug release mechanism for the majority of medicated PEO hydrogel formulations was determined as both drug diffusion and polymer chain relaxation, which is highly desirable for controlled release formulations.

  11. Prevention des Toxicomanies Aupres des Filles avec des Problemes de Comportement: Effets a Court Terme (Prevention of Drug Addiction in Girls with Behavior Problems: Short-Term Effects).

    Science.gov (United States)

    Vitaro, Frank; And Others

    1992-01-01

    This article, written in French, describes and evaluates the first phase of a program to prevent drug addiction among 110 fifth-grade girls with behavior problems in Montreal (Quebec, Canada). Evaluation of the instructional program showed positive results for student knowledge level, attitudes, and behaviors and supported program continuation…

  12. An enzymatic deconjugation method for the analysis of small molecule active drugs on antibody-drug conjugates.

    Science.gov (United States)

    Li, Yi; Gu, Christine; Gruenhagen, Jason; Yehl, Peter; Chetwyn, Nik P; Medley, Colin D

    2016-01-01

    Antibody-drug conjugates (ADCs) are complex therapeutic agents that use the specific targeting properties of antibodies and the highly potent cytotoxicity of small molecule drugs to selectively eliminate tumor cells while limiting the toxicity to normal healthy tissues. Two critical quality attributes of ADCs are the purity and stability of the active small molecule drug linked to the ADC, but these are difficult to assess once the drug is conjugated to the antibody. In this study, we report a enzyme deconjugation approach to cleave small molecule drugs from ADCs, which allows the drugs to be subsequently characterized by reversed-phase high performance liquid chromatography. The model ADC we used in this study utilizes a valine-citrulline linker that is designed to be sensitive to endoproteases after internalization by tumor cells. We screened several proteases to determine the most effective enzyme. Among the 3 cysteine proteases evaluated, papain had the best efficiency in cleaving the small molecule drug from the model ADC. The deconjugation conditions were further optimized to achieve complete cleavage of the small molecule drug. This papain deconjugation approach demonstrated excellent specificity and precision. The purity and stability of the active drug on an ADC drug product was evaluated and the major degradation products of the active drug were identified. The papain deconjugation method was also applied to several other ADCs, with the results suggesting it could be applied generally to ADCs containing a valine-citrulline linker. Our results indicate that the papain deconjugation method is a powerful tool for characterizing the active small molecule drug conjugated to an ADC, and may be useful in ensuring the product quality, efficacy and the safety of ADCs.

  13. Methods for measuring risk-aversion: problems and solutions

    International Nuclear Information System (INIS)

    Thomas, P J

    2013-01-01

    Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead

  14. Methods for measuring risk-aversion: problems and solutions

    Science.gov (United States)

    Thomas, P. J.

    2013-09-01

    Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead.

  15. Variational methods applied to problems of diffusion and reaction

    CERN Document Server

    Strieder, William

    1973-01-01

    This monograph is an account of some problems involving diffusion or diffusion with simultaneous reaction that can be illuminated by the use of variational principles. It was written during a period that included sabbatical leaves of one of us (W. S. ) at the University of Minnesota and the other (R. A. ) at the University of Cambridge and we are grateful to the Petroleum Research Fund for helping to support the former and the Guggenheim Foundation for making possible the latter. We would also like to thank Stephen Prager for getting us together in the first place and for showing how interesting and useful these methods can be. We have also benefitted from correspondence with Dr. A. M. Arthurs of the University of York and from the counsel of Dr. B. D. Coleman the general editor of this series. Table of Contents Chapter 1. Introduction and Preliminaries . 1. 1. General Survey 1 1. 2. Phenomenological Descriptions of Diffusion and Reaction 2 1. 3. Correlation Functions for Random Suspensions 4 1. 4. Mean Free ...

  16. An efficient iterative method for the generalized Stokes problem

    Energy Technology Data Exchange (ETDEWEB)

    Sameh, A. [Univ. of Minnesota, Twin Cities, MN (United States); Sarin, V. [Univ. of Illinois, Urbana, IL (United States)

    1996-12-31

    This paper presents an efficient iterative scheme for the generalized Stokes problem, which arises frequently in the simulation of time-dependent Navier-Stokes equations for incompressible fluid flow. The general form of the linear system is where A = {alpha}M + vT is an n x n symmetric positive definite matrix, in which M is the mass matrix, T is the discrete Laplace operator, {alpha} and {nu} are positive constants proportional to the inverses of the time-step {Delta}t and the Reynolds number Re respectively, and B is the discrete gradient operator of size n x k (k < n). Even though the matrix A is symmetric and positive definite, the system is indefinite due to the incompressibility constraint (B{sup T}u = 0). This causes difficulties both for iterative methods and commonly used preconditioners. Moreover, depending on the ratio {alpha}/{nu}, A behaves like the mass matrix M at one extreme and the Laplace operator T at the other, thus complicating the issue of preconditioning.

  17. SemaTyP: a knowledge graph based literature mining method for drug discovery.

    Science.gov (United States)

    Sang, Shengtian; Yang, Zhihao; Wang, Lei; Liu, Xiaoxia; Lin, Hongfei; Wang, Jian

    2018-05-30

    Drug discovery is the process through which potential new medicines are identified. High-throughput screening and computer-aided drug discovery/design are the two main drug discovery methods for now, which have successfully discovered a series of drugs. However, development of new drugs is still an extremely time-consuming and expensive process. Biomedical literature contains important clues for the identification of potential treatments. It could support experts in biomedicine on their way towards new discoveries. Here, we propose a biomedical knowledge graph-based drug discovery method called SemaTyP, which discovers candidate drugs for diseases by mining published biomedical literature. We first construct a biomedical knowledge graph with the relations extracted from biomedical abstracts, then a logistic regression model is trained by learning the semantic types of paths of known drug therapies' existing in the biomedical knowledge graph, finally the learned model is used to discover drug therapies for new diseases. The experimental results show that our method could not only effectively discover new drug therapies for new diseases, but also could provide the potential mechanism of action of the candidate drugs. In this paper we propose a novel knowledge graph based literature mining method for drug discovery. It could be a supplementary method for current drug discovery methods.

  18. Iterative Reconstruction Methods for Hybrid Inverse Problems in Impedance Tomography

    DEFF Research Database (Denmark)

    Hoffmann, Kristoffer; Knudsen, Kim

    2014-01-01

    For a general formulation of hybrid inverse problems in impedance tomography the Picard and Newton iterative schemes are adapted and four iterative reconstruction algorithms are developed. The general problem formulation includes several existing hybrid imaging modalities such as current density...... impedance imaging, magnetic resonance electrical impedance tomography, and ultrasound modulated electrical impedance tomography, and the unified approach to the reconstruction problem encompasses several algorithms suggested in the literature. The four proposed algorithms are implemented numerically in two...

  19. Producing the 'problem of drugs': A cross national-comparison of 'recovery' discourse in two Australian and British reports.

    Science.gov (United States)

    Lancaster, Kari; Duke, Karen; Ritter, Alison

    2015-07-01

    The notion of 'recovery' as an overarching approach to drug policy remains controversial. This cross-national analysis considers how the problem of drugs was constructed and represented in two key reports on the place of 'recovery' in drug policy, critically examining how the problem of drugs (and the people who use them) are constituted in recovery discourse, and how these problematisations are shaped and disseminated. Bacchi's poststructuralist approach is applied to two documents (one in Britain and one in Australia) to analyse how the 'problem of drugs' and the people who use them are constituted: as problematic users, constraining alternative understandings of the shifting nature of drug use; as responsibilised individuals (in Britain) and as patients (in Australia); as worthy of citizenship in the context of treatment and recovery, silencing the assumption of unworthiness and the loss of rights for those who continue to use drugs in 'problematic' ways. The position of the organisations which produced the reports is considered, with the authority of both organisations resting on their status as independent, apolitical bodies providing 'evidence-based' advice. There is a need to carefully weigh up the desirable and undesirable political effects of these constructions. The meaning of 'recovery' and how it could be realised in policy and practice is still being negotiated. By comparatively analysing how the problem of drugs was produced in 'recovery' discourse in two jurisdictions, at two specific points in the policy debate, we are reminded that ways of thinking about 'problems' reflect specific contexts, and how we are invoked to think about policy responses will be dependent upon these conditions. As 'recovery' continues to evolve, opening up spaces to discuss its contested meanings and effects will be an ongoing endeavour. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Sample preparation method for the combined extraction of ethyl glucuronide and drugs of abuse in hair.

    Science.gov (United States)

    Meier, Ulf; Briellmann, Thomas; Scheurer, Eva; Dussy, Franz

    2018-04-01

    Often in hair analysis, a small hair sample is available while the analysis of a multitude of structurally diverse substances with different concentration ranges is demanded. The analysis of the different substances often requires different sample preparation methods, increasing the amount of required hair sample. When segmental hair analysis is necessary, the amount of hair sample needed is further increased. Therefore, the required sample amount for a full analysis can quickly exceed what is available. To combat this problem, a method for the combined hair sample preparation using a single extraction procedure for analysis of ethyl glucuronide with liquid chromatography-multistage fragmentation mass spectrometry/multiple reaction monitoring (LC-MS 3 /MRM) and common drugs of abuse with LC-MRM was developed. The combined sample preparation is achieved by separating ethyl glucuronide from the drugs of abuse into separate extracts by fractionation in the solid-phase extraction step during sample clean-up. A full validation for all substances for the parameters selectivity, linearity, limit of detection, limit of quantification, accuracy, precision, matrix effects, and recovery was successfully completed. The following drugs of abuse were included in the method: Amphetamine; methamphetamine; 3,4-methylenedioxy-N-methylamphetamine (MDMA); 3,4-methylenedioxyamphetamine (MDA); 3,4-methylenedioxy-N-ethylamphetamine (MDE); morphine; 6-monoacetylmorphine; codeine; acetylcodeine; cocaine; benzoylecgonine; norcocaine; cocaethylene; methadone; 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and methylphenidate. In conclusion, as only 1 sample preparation is needed with 1 aliquot of hair, the presented sample preparation allows an optimal analysis of both ethyl glucuronide and of the drugs of abuse, even when the sample amount is a limiting factor. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Reconstruction Methods for Inverse Problems with Partial Data

    DEFF Research Database (Denmark)

    Hoffmann, Kristoffer

    This thesis presents a theoretical and numerical analysis of a general mathematical formulation of hybrid inverse problems in impedance tomography. This includes problems from several existing hybrid imaging modalities such as Current Density Impedance Imaging, Magnetic Resonance Electrical...... Impedance Tomography, and Ultrasound Modulated Electrical Impedance Tomography. After giving an introduction to hybrid inverse problems in impedance tomography and the mathematical tools that facilitate the related analysis, we explain in detail the stability properties associated with the classification...... of a linearised hybrid inverse problem. This is done using pseudo-differential calculus and theory for overdetermined boundary value problem. Using microlocal analysis we then present novel results on the propagation of singularities, which give a precise description of the distinct features of solutions...

  2. A comprehensive review of assay methods to determine drugs in breast milk and the safety of breastfeeding when taking drugs.

    Science.gov (United States)

    Fríguls, Bibiana; Joya, Xavier; García-Algar, Oscar; Pallás, C R; Vall, Oriol; Pichini, Simona

    2010-06-01

    Most of the licit and illicit drugs consumed by the breastfeeding woman pass into the milk and can modify the production, volume and composition of the milk, as well as hypothetically have short- and long-term harmful effects on the infant. There is much confusion in the scientific community regarding this issue: should a woman breastfeed her baby while continuing to use prescription drugs and/or drugs of abuse? There are many case reports of clinically significant toxicity in breast-fed infants from some substances used by mothers (such as irritability, vomiting, sedation, respiratory depression, shock), but there are too few data on studies conducted in breastfeeding women and their infants to make a realistic risk assessment. The objective measurement of a drug and/or metabolites in maternal milk is the first step when investigating the amount of drug excreted in milk and subsequently calculating the daily dose administered to the breast-fed infant. The present review reports the analytical methods developed to detect different drugs in the breast milk, listing the principal characteristics and validation parameters, advantages and disadvantages. Furthermore, the mechanisms of drug transfer into breast milk are discussed, the correlation between the concentration of the drug in breast milk and potential adverse outcomes on the infant are described for each drug, and suggested harm minimization strategies and approved breastfeeding recommendations are indicated.

  3. Analysing Drug Oversue in a Prescription database: estimation Method Matters

    DEFF Research Database (Denmark)

    Andersen, Morten; Søndergaard, Jens

    2004-01-01

    20 th International Conference on Pharmacoepiemiology and Risk Management. Bordeaux, France. Pharmacoepidemiology and Drug Safety, 2004;13:Sl 1:159......20 th International Conference on Pharmacoepiemiology and Risk Management. Bordeaux, France. Pharmacoepidemiology and Drug Safety, 2004;13:Sl 1:159...

  4. [Moderation-integrated-balance presupposition of Chinese medicine compound and pharmacological problems in traditional Chinese drug research].

    Science.gov (United States)

    Zhao, Jun-Ning

    2017-03-01

    The moderation-integrated-balance presupposition (MIBP) of Chinese medicine compound was first proposed in this paper based on the review of function characteristics and action principles of Chinese medicine compound. Furthermore, the pharmacological problems of traditional Chinese drug research were discussed in details. The results were of important value in accelerating the transformation of traditional Chinese medicine compound, and constructing the new drug innovation and review system for traditional Chinese medicine. Copyright© by the Chinese Pharmaceutical Association.

  5. A symmetrized quasi-diffusion method for solving multidimensional transport problems

    International Nuclear Information System (INIS)

    Miften, M.M.; Larsen, E.W.

    1992-01-01

    In this paper, the authors propose a 'symmetrized' QD (SQD) method in which the non-self-adjoint QD diffusion problem is replaced by two self-adjoint diffusion problems. These problems are more easily discretized and more efficiently solved than in the standard QD method. They also give SQD calculational results for transport problems in x-y geometry

  6. A new method to assess Pavlovian conditioning of psychostimulant drug effects.

    Science.gov (United States)

    Damianopoulos, E N; Carey, R J

    1994-07-01

    Experimental studies of psychoactive drugs by pavlovian drug-conditioning methods, which originally began with investigations of drug-induced responses mediated by the autonomic nervous system, have now been expanded to include drug-induced response effects expressed as modulations of spontaneous motoric behaviors. In the latter application, however, equivalent behavioral response outcomes in post-treatment tests for conditioning can occur following a psychostimulant drug treatment either through drug interference effects on habituation processes, drug-induced stress effects and/or by pavlovian conditioning of the drug-induced motoric activation effect. Current methodologies for the study of pavlovian conditioned drug effects and/or drug sensitization cannot distinguish among these possibilities. This methodological inadequacy was addressed by a modification of the conventional paired-unpaired treatment protocol. In the new protocol, the animal is sequentially placed into two test compartments with the drug treatment administered in conjunction with placement into the second test compartment. This design permits a differentiation of a pavlovian conditioned drug responses from non-conditioned drug effects through continuous measurement of the non-drug behavioral baseline in both the drug and non-drug control treatment groups combined with multiple response measurements and post-treatment tests for conditioning at variable post-conditioning intervals. The present study details the use of the new modified pavlovian protocol with repeated cocaine (10 mg/kg) treatment. A cocaine conditioned response at 1, 7, and 21 days post-conditioning was identified and distinguished from habituation and stress effects.

  7. Hybrid IP/CP Methods for Solving Sports Scheduling Problems

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus Vinther

    2006-01-01

    The field of sports scheduling comprises a challenging research areawith a great variety of hard combinatorial optimization problems andchallenging practical applications. This dissertation gives acomprehensive survey of the area and a number of new contributionsare presented. First a general sol...

  8. Application of the group-theoretical method to physical problems

    OpenAIRE

    Abd-el-malek, Mina B.

    1998-01-01

    The concept of the theory of continuous groups of transformations has attracted the attention of applied mathematicians and engineers to solve many physical problems in the engineering sciences. Three applications are presented in this paper. The first one is the problem of time-dependent vertical temperature distribution in a stagnant lake. Two cases have been considered for the forms of the water parameters, namely water density and thermal conductivity. The second application is the unstea...

  9. Nonlinear Multidimensional Assignment Problems Efficient Conic Optimization Methods and Applications

    Science.gov (United States)

    2015-06-24

    WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Arizona State University School of Mathematical & Statistical Sciences 901 S...SUPPLEMENTARY NOTES 14. ABSTRACT The major goals of this project were completed: the exact solution of previously unsolved challenging combinatorial optimization... combinatorial optimization problem, the Directional Sensor Problem, was solved in two ways. First, heuristically in an engineering fashion and second, exactly

  10. EVALUASI DRUG RELATED PROBLEMS PADA PASIEN GERIATRI DENGAN HIPERTENSI DISERTAI VERTIGO DI RS PANTI RINI YOGYAKARTA AGUSTUS 2013

    Directory of Open Access Journals (Sweden)

    Kresensiana Yosriani

    2016-04-01

    Full Text Available Abstract : This study aimed to evaluate Drug Related Problems (DRPs among hypertensive geriatric patients with vertigo co morbid at Panti Rini Hospital Yogyakarta. This is a non-experimental research descriptive evaluative design using a retrospective medical record data. Collected data including patient's identity; initial, final, and complication diagnosis; cardiovascular system drugs and antivertigo, laboratory data. The inclusion criteria were ≥ 60 years with an initial diagnosis of hypertension with vertigo co morbid, used a diuretic drug, and had creatinine test result. Data were analyzed case by case using selected literatur. There were 20 cases found. Result of the study showed that 100% of patients used antihypertensive as the cardiovascular system drugs and 80% patients used antivertigo as nervous system drugs. There were 18 cases of DRPs found related to the use of antihypertensive and antivertigo. 1 case of dosage too low, 8 cases of adverse drug reaction, and 9 cases of dosege too high. Keywords : hypertension with vertigo co morbid, geriatrics, Drug Related Problems

  11. [Galenical possibilities and problems in protraction of drug effects (author's transl)].

    Science.gov (United States)

    Müller, F

    1976-01-01

    In recent years, dosage forms with sustained release have obtained a significant importance. The technological possibilities for manufacturing are described as coating, embedding and matrix procedures. The range of auxiliary substances, which are responsible for the retardation of drug activity, reaches from lipophilic compounds as lipoids, fatty alcohols and compounds which are forming hydrogels as cellulose derivatives and natural polysaccharides to synthetic polymers derived from acrylic acid. The formulation of the dosage forms requires particular care in respect to the amount of initial and maintenance doses. On account of technological processes, for example during manufacturing of tablets, under certain circumstances the liberation rate is altered. In vitro test methods allow comparisons only then when the results can be counter-checked by in vitro experiments. The release of drug follows different mechanisms, which are described, entirely or in part, to be reactions following the time law of zero or first order. In special cases, a linear correlation is observed as a function of square root of time. The calculation of given special equations for events within the dosage form is feasible from blood-level values.

  12. Polyphony: superposition independent methods for ensemble-based drug discovery.

    Science.gov (United States)

    Pitt, William R; Montalvão, Rinaldo W; Blundell, Tom L

    2014-09-30

    Structure-based drug design is an iterative process, following cycles of structural biology, computer-aided design, synthetic chemistry and bioassay. In favorable circumstances, this process can lead to the structures of hundreds of protein-ligand crystal structures. In addition, molecular dynamics simulations are increasingly being used to further explore the conformational landscape of these complexes. Currently, methods capable of the analysis of ensembles of crystal structures and MD trajectories are limited and usually rely upon least squares superposition of coordinates. Novel methodologies are described for the analysis of multiple structures of a protein. Statistical approaches that rely upon residue equivalence, but not superposition, are developed. Tasks that can be performed include the identification of hinge regions, allosteric conformational changes and transient binding sites. The approaches are tested on crystal structures of CDK2 and other CMGC protein kinases and a simulation of p38α. Known interaction - conformational change relationships are highlighted but also new ones are revealed. A transient but druggable allosteric pocket in CDK2 is predicted to occur under the CMGC insert. Furthermore, an evolutionarily-conserved conformational link from the location of this pocket, via the αEF-αF loop, to phosphorylation sites on the activation loop is discovered. New methodologies are described and validated for the superimposition independent conformational analysis of large collections of structures or simulation snapshots of the same protein. The methodologies are encoded in a Python package called Polyphony, which is released as open source to accompany this paper [http://wrpitt.bitbucket.org/polyphony/].

  13. Violent Behaviors in Drug Addiction: Differential Profiles of Drug-Addicted Patients with and without Violence Problems

    Science.gov (United States)

    Fernandez-Montalvo, Javier; Lopez-Goni, Jose J.; Arteaga, Alfonso

    2012-01-01

    This study explored the prevalence of violent behaviors in patients who are addicted to drugs. A sample of 252 addicted patients (203 male and 49 female) who sought outpatient treatment was assessed. Information on violent behaviors, sociodemographic factors, consumption factors (assessed by the European version of the Addiction Severity Index…

  14. Application of He's variational iteration method to the fifth-order boundary value problems

    International Nuclear Information System (INIS)

    Shen, S

    2008-01-01

    Variational iteration method is introduced to solve the fifth-order boundary value problems. This method provides an efficient approach to solve this type of problems without discretization and the computation of the Adomian polynomials. Numerical results demonstrate that this method is a promising and powerful tool for solving the fifth-order boundary value problems

  15. Dual diagnosis: co-existence of drug, alcohol and mental health problems.

    Science.gov (United States)

    Manley, David

    The Department of Health (DoH) published a set of good practice implementation guidelines on dual diagnosis in May 2002. This guidance suggests that in order to improve the prognosis for clients who have mental health problems and who drink or take drugs problematically, mental health and substance misuse services should adopt an integrated service model. There is a considerable amount of American-based research supporting this approach, but little evidence from the UK researchers demonstrating its application in the UK. This article offers an example of a service that has been developed in the city of Nottingham and argues that this client group will be served most effectively if mental health services support specialist dual-diagnosis resources. Integrated care pathways for this client group can be developed and led by specialist clinicians acting as consultants to mental health services (DoH, 2002a). This consultancy role within mental health services enhances the links needed between substance misuse and mental health services. As a result, specialist dual-diagnosis teams are best placed to increase positive prognoses for clients by ensuring evidence-based substance misuse skills are utilized and adapted by mental health teams to ensure fully integrated care coordination.

  16. The drug abuse problem in Peninsular Malaysia: parent and child differences in knowledge, attitudes and perceptions.

    Science.gov (United States)

    Low, W Y; Zulkifli, S N; Yusof, K; Batumalail, S; Aye, K W

    1996-10-01

    A survey was carried out to gather information on knowledge, attitudes and perception of parents and their children in relation to drug abuse matters. Significantly more teenagers knew more of the cause of drug addiction, as well as places for treatment and rehabilitation. Both teenagers and parents were also aware of reasons why drug addicts find it difficult to change their habits, mainly lacking motivation to stop taking drugs and that drug addicts do not have the power to control themselves. Teenagers were significantly more aware of effects of negative parental attitudes contributing to drug abuse, apart from school factors. Personal experiences before abusing drugs such as knowledge of pleasurable effects of drugs and where to obtain them has also a role to play in leading to drug abuse. There was also agreement that unfulfilled needs such as 'not being respected recognised for ones capabilities' and 'not being loved or treated fairly by parents', were causes of drug abuse. Significantly more teenagers knew of the ways of abusing drugs, mainly by injection, smoking and sniffing, and also sources of information via the mass media, social clubs, rehabilitation centres and schools. However, both the parents and teenagers were relatively ignorant of the long term effects of abusing drugs.

  17. Lost in translation? Role of metabolomics in solving translational problems in drug discovery and development

    NARCIS (Netherlands)

    Greef, J. van der; Adourian, A.; Muntendam, P.; McBurney, R.N.

    2006-01-01

    Too few drug discovery projects generate a marketed drug product, often because preclinical studies fail to predict the clinical experience with a drug candidate. Improving the success of preclinical-to-clinical translation is of paramount importance in optimizing the pharmaceutical value chain.

  18. Why Research Design and Methods Is So Crucial to Understanding Drug Use/Abuse: Introduction to the Special Issue.

    Science.gov (United States)

    Scheier, Lawrence M

    2018-06-01

    The collection of articles in this special issue both raise the bar and inspire new thinking with regard to both design and methodology concerns that influence drug use/abuse research. Thematically speaking, the articles focus on issues related to missing data, response formats, strategies for data harmonization, propensity scoring methods as an alternative to randomized control trials, integrative data analysis, statistical corrections to reduce bias from attrition, challenges faced from conducting large-scale evaluations, and employing abductive theory of method as an alternative to the more traditional hypothetico-deductive reasoning. Collectively, these issues are of paramount importance as they provide specific means to improve our investigative tools and refine the logical framework we employ to examine the problem of drug use/abuse. Each of the authors addresses a specific challenge outlining how it affects our current research efforts and then outlines remedies that can advance the field. To their credit, they have included issues that affect both etiology and prevention, thus broadening our horizons as we learn more about developmental processes causally related to drug use/abuse and intervention strategies that can mitigate developmental vulnerability. This is the essential dialogue required to advance our intellectual tool kit and improve the research skills we bring to bear on the important questions facing the field of drug use/abuse. Ultimately, the goal is to increase our ability to identify the causes and consequences of drug use/abuse and find ways to ameliorate these problems as we engage the public health agenda.

  19. Three anisotropic benchmark problems for adaptive finite element methods

    Czech Academy of Sciences Publication Activity Database

    Šolín, Pavel; Čertík, O.; Korous, L.

    2013-01-01

    Roč. 219, č. 13 (2013), s. 7286-7295 ISSN 0096-3003 R&D Projects: GA AV ČR IAA100760702 Institutional support: RVO:61388998 Keywords : benchmark problem * anisotropic solution * boundary layer Subject RIV: BA - General Mathematics Impact factor: 1.600, year: 2013

  20. Knowledge based method for solving complexity in design problems

    NARCIS (Netherlands)

    Vermeulen, B.

    2007-01-01

    The process of design aircraft systems is becoming more and more complex, due to an increasing amount of requirements. Moreover, the knowledge on how to solve these complex design problems becomes less readily available, because of a decrease in availability of intellectual resources and reduced

  1. On the universal method to solve extremal problems

    NARCIS (Netherlands)

    J. Brinkhuis (Jan)

    2005-01-01

    textabstractSome applications of the theory of extremal problems to mathematics and economics are made more accessible to non-experts. 1.The following fundamental results are known to all users of mathematical techniques, such as economist, econometricians, engineers and ecologists: the fundamental

  2. Jacobi-Davidson methods for generalized MHD-eigenvalue problems

    NARCIS (Netherlands)

    J.G.L. Booten; D.R. Fokkema; G.L.G. Sleijpen; H.A. van der Vorst (Henk)

    1995-01-01

    textabstractA Jacobi-Davidson algorithm for computing selected eigenvalues and associated eigenvectors of the generalized eigenvalue problem $Ax = lambda Bx$ is presented. In this paper the emphasis is put on the case where one of the matrices, say the B-matrix, is Hermitian positive definite. The

  3. A simple method for solving the inverse scattering problem

    International Nuclear Information System (INIS)

    Melnikov, V.N.; Rudyak, B.V.; Zakhariev, V.N.

    1977-01-01

    A new method is proposed for approximate reconstruction of a potential as a step function from scattering data using the completeness relation of solutions of the Schroedinger equation. The suggested method allows one to take into account exactly the additional centrifugal barrier for partial waves with angular momentum l>0, and also the Coulomb potential. The method admits different generalizations. Numerical calculations for checking the method have been performed

  4. ADDRESSING RESEARCH DESIGN PROBLEM IN MIXED METHODS RESEARCH

    OpenAIRE

    Hamed ALAVI; Patrycja HĄBEK

    2016-01-01

    Alongside other disciplines in social sciences, management researchers use mixed methods research more and more in conduct of their scientific investigations. Mixed methods approach can also be used in the field of production engineering. In comparison with traditional quantitative and qualitative research methods, reasons behind increasing popularity of mixed research method in management science can be traced in different factors. First of all, any particular discipline in management can be...

  5. A simple finite element method for linear hyperbolic problems

    International Nuclear Information System (INIS)

    Mu, Lin; Ye, Xiu

    2017-01-01

    Here, we introduce a simple finite element method for solving first order hyperbolic equations with easy implementation and analysis. Our new method, with a symmetric, positive definite system, is designed to use discontinuous approximations on finite element partitions consisting of arbitrary shape of polygons/polyhedra. Error estimate is established. Extensive numerical examples are tested that demonstrate the robustness and flexibility of the method.

  6. Hybrid Method for Solving Inventory Problems with a Linear ...

    African Journals Online (AJOL)

    Osagiede and Omosigho (2004) proposed a direct search method for identifying the number of replenishment when the demand pattern is linearly increasing. The main computational task in this direct search method was associated with finding the optimal number of replenishments. To accelerate the use of this method, the ...

  7. Party package travel: alcohol use and related problems in a holiday resort: a mixed methods study

    Directory of Open Access Journals (Sweden)

    Reinholdt Tine

    2008-10-01

    Full Text Available Abstract Background People travelling abroad tend to increase their use of alcohol and other drugs. In the present study we describe organized party activities in connection with young tourists' drinking, and the differences between young people travelling with and without organized party activities. Methods We conducted ethnographic observations and a cross-sectional survey in Sunny Beach, Bulgaria. Results The behaviour of the guides from two travel agencies strongly promoted heavy drinking, but discouraged illicit drug use. Even after controlling for several potential confounders, young people who travelled with such "party package travel agencies" were more likely to drink 12 or more units when going out. In univariate analyses, they were also more likely to get into fights, but were not more likely to seek medical assistance or medical assistance for an accident or an alcohol-related problem. After controlling for confounders, the association between type of travel agency and getting into fights was no longer significant. Short-term consequences of drinking in the holiday resort did not differ between party package travellers and ordinary package travellers. Conclusion There may be a small impact of party package travels on young people's drinking. Strategies could be developed used to minimise the harm associated with both party package travel and other kinds of travel where heavy substance use is likely to occur.

  8. Approach to Classifying "Design" Drugs and New Potentially Dangerous Chemical Substances, with a Brief Review of the Problem

    Science.gov (United States)

    Asadullin, Azat R.; Galeeva, Elena Kh.; Achmetova, Elvina A.; Nikolaev, Ivan V.

    2016-01-01

    The urgency of this study has become vivid in the light of the growing problem of prevalence and use of new synthetic drug types. Lately there has been a tendency of expanding the range of psychologically active substances (PAS) used by addicts with the purpose of their illegal taking. The aim of this research is an attempt of systematizing and…

  9. Community "San Gregorio." A Christian Educative Response to the Problem of Drug Abuse in Youth Aged 12-18 Years.

    Science.gov (United States)

    Lamus, Jose Antonio Lopez; Sarmiento, Albeiro Saldana

    This pamphlet describes the "San Gregorio" pilot program in Latin America, the first of its type on the continent as a program specifically for adolescent drug addicts. The Christian educative program is designed for males 12-18 years of age, who are addicted to psycho-active substances and evidence serious behavioral problems. It is…

  10. Mixed Methods Research: The "Thing-ness" Problem.

    Science.gov (United States)

    Hesse-Biber, Sharlene

    2015-06-01

    Contemporary mixed methods research (MMR) veers away from a "loosely bounded" to a "bounded" concept that has important negative implications for how qualitatively driven mixed methods approaches are positioned in the field of mixed methods and overall innovation in the praxis of MMR. I deploy the concept of reification defined as taking an object/abstraction and treating it as if it were real such that it takes on the quality of "thing-ness," having a concrete independent existence. I argue that the contemporary reification of mixed methods as a "thing" is fueled by three interrelated factors: (a) the growing formalization of mixed methods as design, (b) the unexamined belief in the "synergy" of mixed methods and, (c) the deployment of a "practical pragmatism" as the "philosophical partner" for mixed methods inquiry. © The Author(s) 2015.

  11. Optimization method for an evolutional type inverse heat conduction problem

    International Nuclear Information System (INIS)

    Deng Zuicha; Yu Jianning; Yang Liu

    2008-01-01

    This paper deals with the determination of a pair (q, u) in the heat conduction equation u t -u xx +q(x,t)u=0, with initial and boundary conditions u(x,0)=u 0 (x), u x vertical bar x=0 =u x vertical bar x=1 =0, from the overspecified data u(x, t) = g(x, t). By the time semi-discrete scheme, the problem is transformed into a sequence of inverse problems in which the unknown coefficients are purely space dependent. Based on the optimal control framework, the existence, uniqueness and stability of the solution (q, u) are proved. A necessary condition which is a couple system of a parabolic equation and parabolic variational inequality is deduced

  12. Optimization method for an evolutional type inverse heat conduction problem

    Science.gov (United States)

    Deng, Zui-Cha; Yu, Jian-Ning; Yang, Liu

    2008-01-01

    This paper deals with the determination of a pair (q, u) in the heat conduction equation u_t-u_{xx}+q(x,t)u=0, with initial and boundary conditions u(x,0)=u_0(x),\\qquad u_x|_{x=0}=u_x|_{x=1}=0, from the overspecified data u(x, t) = g(x, t). By the time semi-discrete scheme, the problem is transformed into a sequence of inverse problems in which the unknown coefficients are purely space dependent. Based on the optimal control framework, the existence, uniqueness and stability of the solution (q, u) are proved. A necessary condition which is a couple system of a parabolic equation and parabolic variational inequality is deduced.

  13. A finite difference method for free boundary problems

    KAUST Repository

    Fornberg, Bengt

    2010-04-01

    Fornberg and Meyer-Spasche proposed some time ago a simple strategy to correct finite difference schemes in the presence of a free boundary that cuts across a Cartesian grid. We show here how this procedure can be combined with a minimax-based optimization procedure to rapidly solve a wide range of elliptic-type free boundary value problems. © 2009 Elsevier B.V. All rights reserved.

  14. Krylov Subspace Methods for Saddle Point Problems with Indefinite Preconditioning

    Czech Academy of Sciences Publication Activity Database

    Rozložník, Miroslav; Simoncini, V.

    2002-01-01

    Roč. 24, č. 2 (2002), s. 368-391 ISSN 0895-4798 R&D Projects: GA ČR GA101/00/1035; GA ČR GA201/00/0080 Institutional research plan: AV0Z1030915 Keywords : saddle point problems * preconditioning * indefinite linear systems * finite precision arithmetic * conjugate gradients Subject RIV: BA - General Mathematics Impact factor: 0.753, year: 2002

  15. WYD method for an eigen solution of coupled problems

    Directory of Open Access Journals (Sweden)

    A Harapin

    2016-04-01

    Full Text Available Designing efficient and stable algorithm for finding the eigenvalues andeigenvectors is very important from the static as well as the dynamic aspectin coupled problems. Modal analysis requires first few significant eigenvectorsand eigenvalues while direct integration requires the highest value toascertain the length of the time step that satisfies the stability condition.The paper first presents the modification of the well known WYDmethod for a solution of single field problems: an efficient and numericallystable algorithm for computing eigenvalues and the correspondingeigenvectors. The modification is based on the special choice of thestarting vector. The starting vector is the static solution of displacements forthe applied load, defined as the product of the mass matrix and the unitdisplacement vector. The starting vector is very close to the theoreticalsolution, which is important in cases of small subspaces.Additionally, the paper briefly presents the adopted formulation for solvingthe fluid-structure coupled systems problems which is based on a separatesolution for each field. Individual fields (fluid and structure are solvedindependently, taking in consideration the interaction information transferbetween them at every stage of the iterative solution process. The assessmentof eigenvalues and eigenvectors for multiple fields is also presented. This eigenproblem is more complicated than the one for the ordinary structural analysis,as the formulation produces non-symmetrical matrices.Finally, a numerical example for the eigen solution coupled fluidstructureproblem is presented to show the efficiency and the accuracy ofthe developed algorithm.

  16. A General Iterative Method of Fixed Points for Mixed Equilibrium Problems and Variational Inclusion Problems

    Directory of Open Access Journals (Sweden)

    Phayap Katchang

    2010-01-01

    Full Text Available The purpose of this paper is to investigate the problem of finding a common element of the set of solutions for mixed equilibrium problems, the set of solutions of the variational inclusions with set-valued maximal monotone mappings and inverse-strongly monotone mappings, and the set of fixed points of a family of finitely nonexpansive mappings in the setting of Hilbert spaces. We propose a new iterative scheme for finding the common element of the above three sets. Our results improve and extend the corresponding results of the works by Zhang et al. (2008, Peng et al. (2008, Peng and Yao (2009, as well as Plubtieng and Sriprad (2009 and some well-known results in the literature.

  17. A Prospective Method to Guide Small Molecule Drug Design

    Science.gov (United States)

    Johnson, Alan T.

    2015-01-01

    At present, small molecule drug design follows a retrospective path when considering what analogs are to be made around a current hit or lead molecule with the focus often on identifying a compound with higher intrinsic potency. What this approach overlooks is the simultaneous need to also improve the physicochemical (PC) and pharmacokinetic (PK)…

  18. Addressing Research Design Problem in Mixed Methods Research

    Science.gov (United States)

    Alavi, Hamed; Hąbek, Patrycja

    2016-03-01

    Alongside other disciplines in social sciences, management researchers use mixed methods research more and more in conduct of their scientific investigations. Mixed methods approach can also be used in the field of production engineering. In comparison with traditional quantitative and qualitative research methods, reasons behind increasing popularity of mixed research method in management science can be traced in different factors. First of all, any particular discipline in management can be theoretically related to it. Second is that concurrent approach of mixed research method to inductive and deductive research logic provides researchers with opportunity to generate theory and test hypothesis in one study simultaneously. In addition, it provides a better justification for chosen method of investigation and higher validity for obtained answers to research questions. Despite increasing popularity of mixed research methods among management scholars, there is still need for a comprehensive approach to research design typology and process in mixed research method from the perspective of management science. The authors in this paper try to explain fundamental principles of mixed research method, its typology and different steps in its design process.

  19. A hierarchical method for structural topology design problems with local stress and displacement constraints

    DEFF Research Database (Denmark)

    Stolpe, Mathias; Stidsen, Thomas K.

    2005-01-01

    In this paper we present a hierarchical optimization method for finding feasible true 0-1 solutions to finite element based topology design problems. The topology design problems are initially modeled as non-convex mixed 0-1 programs. The hierarchical optimization method is applied to the problem...... and then successively refined as needed. At each level of design mesh refinement, a neighborhood optimization method is used to solve the problem considered. The non-convex topology design problems are equivalently reformulated as convex all-quadratic mixed 0-1 programs. This reformulation enables the use of methods...... of minimizing the weight of a structure subject to displacement and local design-dependent stress constraints. The method iteratively solves a sequence of problems of increasing size of the same type as the original problem. The problems are defined on a design mesh which is initially coarse...

  20. A hierarchical method for discrete structural topology design problems with local stress and displacement constraints

    DEFF Research Database (Denmark)

    Stolpe, Mathias; Stidsen, Thomas K.

    2007-01-01

    In this paper, we present a hierarchical optimization method for finding feasible true 0-1 solutions to finite-element-based topology design problems. The topology design problems are initially modelled as non-convex mixed 0-1 programs. The hierarchical optimization method is applied to the problem...... and then successively refined as needed. At each level of design mesh refinement, a neighbourhood optimization method is used to treat the problem considered. The non-convex topology design problems are equivalently reformulated as convex all-quadratic mixed 0-1 programs. This reformulation enables the use of methods...... of minimizing the weight of a structure subject to displacement and local design-dependent stress constraints. The method iteratively treats a sequence of problems of increasing size of the same type as the original problem. The problems are defined on a design mesh which is initially coarse...

  1. Topology optimization of bounded acoustic problems using the hybrid finite element-wave based method

    DEFF Research Database (Denmark)

    Goo, Seongyeol; Wang, Semyung; Kook, Junghwan

    2017-01-01

    This paper presents an alternative topology optimization method for bounded acoustic problems that uses the hybrid finite element-wave based method (FE-WBM). The conventional method for the topology optimization of bounded acoustic problems is based on the finite element method (FEM), which...

  2. Method effects: the problem with negatively versus positively keyed items.

    Science.gov (United States)

    Lindwall, Magnus; Barkoukis, Vassilis; Grano, Caterina; Lucidi, Fabio; Raudsepp, Lennart; Liukkonen, Jarmo; Thøgersen-Ntoumani, Cecilie

    2012-01-01

    Using confirmatory factor analyses, we examined method effects on Rosenberg's Self-Esteem Scale (RSES; Rosenberg, 1965) in a sample of older European adults. Nine hundred forty nine community-dwelling adults 60 years of age or older from 5 European countries completed the RSES as well as measures of depression and life satisfaction. The 2 models that had an acceptable fit with the data included method effects. The method effects were associated with both positively and negatively worded items. Method effects models were invariant across gender and age, but not across countries. Both depression and life satisfaction predicted method effects. Individuals with higher depression scores and lower life satisfaction scores were more likely to endorse negatively phrased items.

  3. A Review of Methods for Moving Boundary Problems

    Science.gov (United States)

    2009-07-01

    the bound- ary value problem for the eikonal equation: ‖∇u‖ = 1 for x ∈ Ω (29) u = 0 for x ∈ Γ (30) ERDC/CHL TR-09-10 8 where ‖ ‖ is the Euclidean norm...Solutions of the eikonal equation can in turn be characterized as steady state solutions of the initial value prob- lem ut + sgn(u0)(‖∇u‖ − 1) = 0...LS using the eikonal equation and use the NCI equation for the LS dynam- ics. The complete system of equations in weak form is ∫ Ω (‖∇u‖ − 1)wdV = 0

  4. Primary drug resistance in a region with high burden of tuberculosis. A critical problem.

    Science.gov (United States)

    Villa-Rosas, Cecilia; Laniado-Laborín, Rafael; Oceguera-Palao, Lorena

    2015-01-01

    To determine rates of drug resistance in new cases of pulmonary tuberculosis in a region with a high burden of the disease. New case suspects were referred for drug susceptibility testing. 28.9% of new cases were resistant to at least one first line drug; 3.9% had a multidrug-resistant strain, 15.6% a monoresistant strain and 9.4% a polyresistant strain. Our rate of drug resistant tuberculosis in new cases is very high; this has important clinical implications, since even monoresistance can have a negative impact on the outcome of new cases treated empirically with a six month regimen.

  5. SILVER NANOPARTICLES IN THE SOLUTION OF THE PROBLEM OF DRUG RESISTANCE IN MYCOBACTERIUM TUBERCULOSIS

    Directory of Open Access Journals (Sweden)

    A. V. Zaharov

    2017-01-01

    Full Text Available The goal — a scientific evaluation of the effectiveness and safety of NHS in the treatment of experimental drug-resistant tuberculosis. Materials and methods. Used silver nanoparticles obtained by an electrochemical method. With a size of 5-60 nm, 120-270 kontsentratsiey- 1 mcm² and the size of the stabilizer shell — 2-5 nm. 750 crops studied Inhibitory activity of the silver nanoparticles in an isolated form and as part of a nanocomposite with chemotherapy in concentrations of 5; 25 and 50 mcg/ml. Defines the minimum inhibitory concentration of bactericidal nanoparticles composed of a nanocomposite with isoniazid. To evaluate the morphometry M.tuberculosis used atomic force microscopy. Toxicology nanopreparations studied 83 non-linear white mice and 146 white rats. Chemotherapeutic Activity nanopreparations determined on an experimental model of tuberculosis in 65 white male mice imbrednoy line BALB/c. Infectivity dose amount 5х106 colony forming units injected into the sinus venosus animal eyes. Isoniazid, nanoparticles and nanocomposite began administered 14 days after infection by intramuscular injection daily. Treatment efficacy was determined by comparing the evaluation criteria in the experimental and control groups of animals. Evaluated the following indicators: survival index, body mass index and weight of target organ, lesions index, index smear and inoculation of affected organs. Conducted pathological examination. Results. When using isoniazid, which had resistant pathogens, with silver nanoparticles full and significant inhibition of the growth of the M.tuberculosis observed in 49,2% of cases. When the concentration of the nanoparticles 5 mcg/ml in the composite bactericidal activity reached 91,3%. The minimum inhibitory concentration of silver nanoperticles in combination with isoniazid was 2,5 mcg/ml, the minimum bactericidal — 5 mcg /ml. There have been changes in the M.tuberculosis morphometry under the influence of the

  6. Application of autoradiography methods for solving problems of microelectronics

    International Nuclear Information System (INIS)

    Frejer, K.; Trojtler, Kh.-Kh.; Birkgol'ts, V.

    1979-01-01

    Methods of contact autoradiography with halogen-silver emulsions and autoradiography, caused by the interaction of neutrons with solid track detectors, are successfully used for determination of lateral and longitudal distributions of matter in the basic semiconductor material as well as in the frameworks of its preparation. Possibilities for application and power parameters of some autoradiographic methods related to sensitivity of detection and local resolution are considered on the example of the basic material - silicon. In this case, special attention was paid on investigation of elements combibation, for example: boron/phosphorus as well as on the methods of correlation of solid track and halogen-silver autoradiogrammes [ru

  7. An Efficient Optimization Method for Solving Unsupervised Data Classification Problems

    Directory of Open Access Journals (Sweden)

    Parvaneh Shabanzadeh

    2015-01-01

    Full Text Available Unsupervised data classification (or clustering analysis is one of the most useful tools and a descriptive task in data mining that seeks to classify homogeneous groups of objects based on similarity and is used in many medical disciplines and various applications. In general, there is no single algorithm that is suitable for all types of data, conditions, and applications. Each algorithm has its own advantages, limitations, and deficiencies. Hence, research for novel and effective approaches for unsupervised data classification is still active. In this paper a heuristic algorithm, Biogeography-Based Optimization (BBO algorithm, was adapted for data clustering problems by modifying the main operators of BBO algorithm, which is inspired from the natural biogeography distribution of different species. Similar to other population-based algorithms, BBO algorithm starts with an initial population of candidate solutions to an optimization problem and an objective function that is calculated for them. To evaluate the performance of the proposed algorithm assessment was carried on six medical and real life datasets and was compared with eight well known and recent unsupervised data classification algorithms. Numerical results demonstrate that the proposed evolutionary optimization algorithm is efficient for unsupervised data classification.

  8. Nonsmooth Newton method for Fischer function reformulation of contact force problems for interactive rigid body simulation

    DEFF Research Database (Denmark)

    Silcowitz, Morten; Niebe, Sarah Maria; Erleben, Kenny

    2009-01-01

    contact response. In this paper, we present a new approach to contact force determination. We reformulate the contact force problem as a nonlinear root search problem, using a Fischer function. We solve this problem using a generalized Newton method. Our new Fischer - Newton method shows improved...... qualities for specific configurations where the most widespread alternative, the Projected Gauss-Seidel method, fails. Experiments show superior convergence properties of the exact Fischer - Newton method....

  9. MULTI-CRITERIA PROGRAMMING METHODS AND PRODUCTION PLAN OPTIMIZATION PROBLEM SOLVING IN METAL INDUSTRY

    OpenAIRE

    Tunjo Perić; Željko Mandić

    2017-01-01

    This paper presents the production plan optimization in the metal industry considered as a multi-criteria programming problem. We first provided the definition of the multi-criteria programming problem and classification of the multicriteria programming methods. Then we applied two multi-criteria programming methods (the STEM method and the PROMETHEE method) in solving a problem of multi-criteria optimization production plan in a company from the metal industry. The obtained resul...

  10. On illicit drug policies; methods of evaluation and comments on recent practices.

    Science.gov (United States)

    Trovato, Giovanni; Vezzani, Antonio

    2013-06-01

    This contribution provides an overview of different approaches used to analyse drug policies within and across countries. Besides the great number of cost of illness studies which have contributed to the assessment of health harms and risks associated to the drug use, most of the recent efforts have focused on the creation of synthetic indices to classify countries around the world or to evaluate particular law enforcement policies in some countries. This is probably due to a general lack of comparable data across countries. The wide variety of budgetary practices in the drugs field in Europe contributes to the problems that exist in estimating drug-related public expenditure. These heterogeneous accounting practices, together with the complexity of the drug phenomenon and the multiplicity of perspectives on the issue, strongly constrains the possibility of economically evaluate and compare drug laws across countries.

  11. Anthropology with algorithms? An exploration of online drug knowledge using digital methods

    NARCIS (Netherlands)

    Krieg, L.J.; Berning, M.; Hardon, A.

    2017-01-01

    Based on a study of more than twenty thousand reports on drug experiences from the online drug education portal Erowid, this article argues that the integration of ethnographic methods with computational methods and digital data analysis, including so-called big data, is not only possible but highly

  12. Statistical Analysis of a Method to Predict Drug-Polymer Miscibility

    DEFF Research Database (Denmark)

    Knopp, Matthias Manne; Olesen, Niels Erik; Huang, Yanbin

    2016-01-01

    In this study, a method proposed to predict drug-polymer miscibility from differential scanning calorimetry measurements was subjected to statistical analysis. The method is relatively fast and inexpensive and has gained popularity as a result of the increasing interest in the formulation of drug...... as provided in this study. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci....

  13. The problem of accounting methods in connection to company valuation

    Directory of Open Access Journals (Sweden)

    Michaela Beranová

    2013-01-01

    Full Text Available Valuation of a company is not only a calculation but it represents complex set of processes which are mutually interconnected and which are more or less important in the process of company valuation in dependence of the value category inquired. One of these processes is the financial analysis which objective is not only to prove, subsequently the strategic analysis, going concern of a company, but its outcomes are the starting-point of financial plan preparation that is needed in order to apply income-based methods of company valuation. It is generally accepted that results of financial ratios differ in implications of applied accounting methods. The objective of this paper is to frame an influence of accounting methods on the income-based value of a company while the stress is put on the methods of inventory measurement in the context of both, in context of the Czech accounting law as well as of the International Financial Reporting Standards.

  14. Application of meshless EFG method in fluid flow problems

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    viewpoint of computer time but require less time in the preparation of data. ..... Krongauz Y, Organ D, Fleming M, Krysl P 1996 Meshless methods: an overview and ... Dolbow J, Belytschko T 1998 An introduction to programming the meshless ...

  15. Mixed arrays - problems with current methods and rules

    International Nuclear Information System (INIS)

    Mennerdahl, D.

    1987-01-01

    Simplified methods are used to control the criticality safety of mixed arrays (non-identical units) in storage or in transport. The basis for these methods is that the analyses of arrays of identical units are sufficient for drawing proper conclusions on mixed arrays. In a recent study of the rules for transport, two general flaws in such methods have been identified. One flaw is caused by increased neutron return rate to the central part of the array. The other flaw is caused by increased neutron coupling between two or more fissile units in an array. In both cases, replacement of fissile units with other units, which appear to be less reactive, can lead to criticality. This paper shows that the two flaws are common in also in current methods used for storage of fissile materials. (author)

  16. A numerical method for eigenvalue problems in modeling liquid crystals

    Energy Technology Data Exchange (ETDEWEB)

    Baglama, J.; Farrell, P.A.; Reichel, L.; Ruttan, A. [Kent State Univ., OH (United States); Calvetti, D. [Stevens Inst. of Technology, Hoboken, NJ (United States)

    1996-12-31

    Equilibrium configurations of liquid crystals in finite containments are minimizers of the thermodynamic free energy of the system. It is important to be able to track the equilibrium configurations as the temperature of the liquid crystals decreases. The path of the minimal energy configuration at bifurcation points can be computed from the null space of a large sparse symmetric matrix. We describe a new variant of the implicitly restarted Lanczos method that is well suited for the computation of extreme eigenvalues of a large sparse symmetric matrix, and we use this method to determine the desired null space. Our implicitly restarted Lanczos method determines adoptively a polynomial filter by using Leja shifts, and does not require factorization of the matrix. The storage requirement of the method is small, and this makes it attractive to use for the present application.

  17. Use of deterministic methods in survey calculations for criticality problems

    International Nuclear Information System (INIS)

    Hutton, J.L.; Phenix, J.; Course, A.F.

    1991-01-01

    A code package using deterministic methods for solving the Boltzmann Transport equation is the WIMS suite. This has been very successful for a range of situations. In particular it has been used with great success to analyse trends in reactivity with a range of changes in state. The WIMS suite of codes have a range of methods and are very flexible in the way they can be combined. A wide variety of situations can be modelled ranging through all the current Thermal Reactor variants to storage systems and items of chemical plant. These methods have recently been enhanced by the introduction of the CACTUS method. This is based on a characteristics technique for solving the Transport equation and has the advantage that complex geometrical situations can be treated. In this paper the basis of the method is outlined and examples of its use are illustrated. In parallel with these developments the validation for out of pile situations has been extended to include experiments with relevance to criticality situations. The paper will summarise this evidence and show how these results point to a partial re-adoption of deterministic methods for some areas of criticality. The paper also presents results to illustrate the use of WIMS in criticality situations and in particular show how it can complement codes such as MONK when used for surveying the reactivity effect due to changes in geometry or materials. (Author)

  18. $h - p$ Spectral element methods for elliptic problems on non-smooth domains using parallel computers

    NARCIS (Netherlands)

    Tomar, S.K.

    2002-01-01

    It is well known that elliptic problems when posed on non-smooth domains, develop singularities. We examine such problems within the framework of spectral element methods and resolve the singularities with exponential accuracy.

  19. Novel Methods for Drug-Target Interaction Prediction using Graph Mining

    KAUST Repository

    Ba Alawi, Wail

    2016-01-01

    -target interactions (DTIs) before any experiments are done. However, many of these approaches suffer from unacceptable levels of false positives. We developed two novel methods based on graph mining networks of drugs and targets. The first method (DASPfind) finds all

  20. Alcohol and drug problems and sexual and physical abuse at three ...

    African Journals Online (AJOL)

    Background Alcohol is the most important substance of abuse in South Africa. There are, however, reports of an increase in the use of other drugs among adolescents. The aim of this study was to assess the use of alcohol and other drugs of abuse and their association with physical or sexual abuse in three urban high ...

  1. The intelligence of dual simplex method to solve linear fractional fuzzy transportation problem.

    Science.gov (United States)

    Narayanamoorthy, S; Kalyani, S

    2015-01-01

    An approach is presented to solve a fuzzy transportation problem with linear fractional fuzzy objective function. In this proposed approach the fractional fuzzy transportation problem is decomposed into two linear fuzzy transportation problems. The optimal solution of the two linear fuzzy transportations is solved by dual simplex method and the optimal solution of the fractional fuzzy transportation problem is obtained. The proposed method is explained in detail with an example.

  2. The Intelligence of Dual Simplex Method to Solve Linear Fractional Fuzzy Transportation Problem

    Directory of Open Access Journals (Sweden)

    S. Narayanamoorthy

    2015-01-01

    Full Text Available An approach is presented to solve a fuzzy transportation problem with linear fractional fuzzy objective function. In this proposed approach the fractional fuzzy transportation problem is decomposed into two linear fuzzy transportation problems. The optimal solution of the two linear fuzzy transportations is solved by dual simplex method and the optimal solution of the fractional fuzzy transportation problem is obtained. The proposed method is explained in detail with an example.

  3. Overlapping Schwarz for Nonlinear Problems. An Element Agglomeration Nonlinear Additive Schwarz Preconditioned Newton Method for Unstructured Finite Element Problems

    Energy Technology Data Exchange (ETDEWEB)

    Cai, X C; Marcinkowski, L; Vassilevski, P S

    2005-02-10

    This paper extends previous results on nonlinear Schwarz preconditioning ([4]) to unstructured finite element elliptic problems exploiting now nonlocal (but small) subspaces. The non-local finite element subspaces are associated with subdomains obtained from a non-overlapping element partitioning of the original set of elements and are coarse outside the prescribed element subdomain. The coarsening is based on a modification of the agglomeration based AMGe method proposed in [8]. Then, the algebraic construction from [9] of the corresponding non-linear finite element subproblems is applied to generate the subspace based nonlinear preconditioner. The overall nonlinearly preconditioned problem is solved by an inexact Newton method. Numerical illustration is also provided.

  4. Spectral methods and their implementation to solution of aerodynamic and fluid mechanic problems

    Science.gov (United States)

    Streett, C. L.

    1987-01-01

    Fundamental concepts underlying spectral collocation methods, especially pertaining to their use in the solution of partial differential equations, are outlined. Theoretical accuracy results are reviewed and compared with results from test problems. A number of practical aspects of the construction and use of spectral methods are detailed, along with several solution schemes which have found utility in applications of spectral methods to practical problems. Results from a few of the successful applications of spectral methods to problems of aerodynamic and fluid mechanic interest are then outlined, followed by a discussion of the problem areas in spectral methods and the current research under way to overcome these difficulties.

  5. MULTI-CRITERIA PROGRAMMING METHODS AND PRODUCTION PLAN OPTIMIZATION PROBLEM SOLVING IN METAL INDUSTRY

    Directory of Open Access Journals (Sweden)

    Tunjo Perić

    2017-09-01

    Full Text Available This paper presents the production plan optimization in the metal industry considered as a multi-criteria programming problem. We first provided the definition of the multi-criteria programming problem and classification of the multicriteria programming methods. Then we applied two multi-criteria programming methods (the STEM method and the PROMETHEE method in solving a problem of multi-criteria optimization production plan in a company from the metal industry. The obtained results indicate a high efficiency of the applied methods in solving the problem.

  6. Solution of problems in calculus of variations via He's variational iteration method

    International Nuclear Information System (INIS)

    Tatari, Mehdi; Dehghan, Mehdi

    2007-01-01

    In the modeling of a large class of problems in science and engineering, the minimization of a functional is appeared. Finding the solution of these problems needs to solve the corresponding ordinary differential equations which are generally nonlinear. In recent years He's variational iteration method has been attracted a lot of attention of the researchers for solving nonlinear problems. This method finds the solution of the problem without any discretization of the equation. Since this method gives a closed form solution of the problem and avoids the round off errors, it can be considered as an efficient method for solving various kinds of problems. In this research He's variational iteration method will be employed for solving some problems in calculus of variations. Some examples are presented to show the efficiency of the proposed technique

  7. Monte Carlo methods in electron transport problems. Pt. 1

    International Nuclear Information System (INIS)

    Cleri, F.

    1989-01-01

    The condensed-history Monte Carlo method for charged particles transport is reviewed and discussed starting from a general form of the Boltzmann equation (Part I). The physics of the electronic interactions, together with some pedagogic example will be introduced in the part II. The lecture is directed to potential users of the method, for which it can be a useful introduction to the subject matter, and wants to establish the basis of the work on the computer code RECORD, which is at present in a developing stage

  8. Boundary integral equation methods in eigenvalue problems of elastodynamics and thin plates

    CERN Document Server

    Kitahara, M

    1985-01-01

    The boundary integral equation (BIE) method has been used more and more in the last 20 years for solving various engineering problems. It has important advantages over other techniques for numerical treatment of a wide class of boundary value problems and is now regarded as an indispensable tool for potential problems, electromagnetism problems, heat transfer, fluid flow, elastostatics, stress concentration and fracture problems, geomechanical problems, and steady-state and transient electrodynamics.In this book, the author gives a complete, thorough and detailed survey of the method. It pro

  9. A nonsmooth nonlinear conjugate gradient method for interactive contact force problems

    DEFF Research Database (Denmark)

    Silcowitz, Morten; Abel, Sarah Maria Niebe; Erleben, Kenny

    2010-01-01

    of a nonlinear complementarity problem (NCP), which can be solved using an iterative splitting method, such as the projected Gauss–Seidel (PGS) method. We present a novel method for solving the NCP problem by applying a Fletcher–Reeves type nonlinear nonsmooth conjugate gradient (NNCG) type method. We analyze...... and present experimental convergence behavior and properties of the new method. Our results show that the NNCG method has at least the same convergence rate as PGS, and in many cases better....

  10. Characterizing Reinforcement Learning Methods through Parameterized Learning Problems

    Science.gov (United States)

    2011-06-03

    extraneous. The agent could potentially adapt these representational aspects by applying methods from feature selection ( Kolter and Ng, 2009; Petrik et al...611–616. AAAI Press. Kolter , J. Z. and Ng, A. Y. (2009). Regularization and feature selection in least-squares temporal difference learning. In A. P

  11. Homogenization of metamaterials: Parameters retrieval methods and intrinsic problems

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Lavrinenko, Andrei

    2010-01-01

    Metamaterials (MTMs) claim a lot of attention worldwide. Description of the MTMs in terms of effective parameters is a simple and useful tool for characterisation of their electromagnetic properties. So a reliable effective parameters restoration method is on demand. In this paper we report about...

  12. The Fourier transform method for infinite medium resonance absorption problems

    International Nuclear Information System (INIS)

    Menon, S.V.G.; Sahni, D.C.

    1978-01-01

    A new method, using Fourier transforms, is developed for solving the integral equation of slowing down of neutrons in the resonance region. The transformations replace the slowing down equation with a discontinuous kernel by an integral equation with a continuous kernel over the interval (-infinity, infinity). Further the Doppler broadened line shape functions have simple analytical representations in the transform variable. In the limit of zero temperature, the integral equation reduces to a second order differential equation. Accurate expressions for the zero temperature resonance integrals are derived, using the WKB method. In general, the integral equation is seen to be amenable to solution by Ganss-Hermite quadrature formule. Doppler coefficients of 238 U resonances are given and compared with Monte Carlo calculations. The method is extended to include the effect of interference between neighbouring resonances of an absorber. For the case of two interfering resonances the slowing down equation is transformed to the coupled integral equations that are amenable to solution by methods indicated earlier. Numerical results presented for the low lying thorium-232 doublet show that the Doppler coefficients of the resonances are reduced considerably because of the overlap between them. (author)

  13. Preconditioned Iterative Methods for Solving Weighted Linear Least Squares Problems

    Czech Academy of Sciences Publication Activity Database

    Bru, R.; Marín, J.; Mas, J.; Tůma, Miroslav

    2014-01-01

    Roč. 36, č. 4 (2014), A2002-A2022 ISSN 1064-8275 Institutional support: RVO:67985807 Keywords : preconditioned iterative methods * incomplete decompositions * approximate inverses * linear least squares Subject RIV: BA - General Mathematics Impact factor: 1.854, year: 2014

  14. Spatial homogenization method based on the inverse problem

    International Nuclear Information System (INIS)

    Tóta, Ádám; Makai, Mihály

    2015-01-01

    Highlights: • We derive a spatial homogenization method in slab and cylindrical geometries. • The fluxes and the currents on the boundary are preserved. • The reaction rates and the integral of the fluxes are preserved. • We present verification computations utilizing two- and four-energy groups. - Abstract: We present a method for deriving homogeneous multi-group cross sections to replace a heterogeneous region’s multi-group cross sections; providing that the fluxes, the currents on the external boundary, the reaction rates and the integral of the fluxes are preserved. We consider one-dimensional geometries: a symmetric slab and a homogeneous cylinder. Assuming that the boundary fluxes are given, two response matrices (RMs) can be defined concerning the current and the flux integral. The first one derives the boundary currents from the boundary fluxes, while the second one derives the flux integrals from the boundary fluxes. Further RMs can be defined that connects reaction rates to the boundary fluxes. Assuming that these matrices are known, we present formulae that reconstruct the multi-group diffusion cross-section matrix, the diffusion coefficients and the reaction cross sections in case of one-dimensional (1D) homogeneous regions. We apply these formulae to 1D heterogeneous regions and thus obtain a homogenization method. This method produces such an equivalent homogeneous material, that the fluxes and the currents on the external boundary, the reaction rates and the integral of the fluxes are preserved for any boundary fluxes. We carry out the exact derivations in 1D slab and cylindrical geometries. Verification computations for the presented homogenization method were performed using two- and four-group material cross sections, both in a slab and in a cylindrical geometry

  15. A finite-dimensional reduction method for slightly supercritical elliptic problems

    Directory of Open Access Journals (Sweden)

    Riccardo Molle

    2004-01-01

    Full Text Available We describe a finite-dimensional reduction method to find solutions for a class of slightly supercritical elliptic problems. A suitable truncation argument allows us to work in the usual Sobolev space even in the presence of supercritical nonlinearities: we modify the supercritical term in such a way to have subcritical approximating problems; for these problems, the finite-dimensional reduction can be obtained applying the methods already developed in the subcritical case; finally, we show that, if the truncation is realized at a sufficiently large level, then the solutions of the approximating problems, given by these methods, also solve the supercritical problems when the parameter is small enough.

  16. Using the method of ideal point to solve dual-objective problem for production scheduling

    Directory of Open Access Journals (Sweden)

    Mariia Marko

    2016-07-01

    Full Text Available In practice, there are often problems, which must simultaneously optimize several criterias. This so-called multi-objective optimization problem. In the article we consider the use of the method ideal point to solve the two-objective optimization problem of production planning. The process of finding solution to the problem consists of a series of steps where using simplex method, we find the ideal point. After that for solving a scalar problems, we use the method of Lagrange multipliers

  17. Solid dispersions, part II: new strategies in manufacturing methods for dissolution rate enhancement of poorly water-soluble drugs.

    Science.gov (United States)

    Bikiaris, Dimitrios N

    2011-12-01

    The absorption of poorly water-soluble drugs, when presented in the crystalline state to the gastrointestinal tract, is typically dissolution rate-limited, and according to BCS these drugs belong mainly to class II. Both dissolution kinetics and solubility are particle size dependent. Nowadays, various techniques are available to the pharmaceutical industry for dissolution rate enhancement of such drugs. Among such techniques, nanosuspensions and drug formulation in solid dispersions are those with the highest interest. This review discusses strategies undertaken over the last 10 years, which have been applied for the dissolution enhancement of poorly water-soluble drugs; such processes include melt mixing, electrospinning, microwave irradiation and the use of inorganic nanoparticles. Many problems in this field still need to be solved, mainly the use of toxic solvents, and for this reason the use of innovative new procedures and materials will increase over the coming years. Melt mixing remains extremely promising for the preparation of SDs and will probably become the most used method in the future for the preparation of solid drug dispersions.

  18. Acute health problems due to recreational drug use in patients presenting to an urban emergency department in Switzerland

    OpenAIRE

    Liakoni, Evangelia; Dolder, Patrick C.; Rentsch, Katharina; Liechti, Matthias E.

    2015-01-01

    QUESTIONS UNDER STUDY: To describe acute toxicity of recreational drugs including novel psychoactive substances. METHODS: We included all cases presenting at the emergency department (ED) of the University Hospital of Basel, Switzerland, between October 2013 and September 2014 with acute toxicity due to self-reported recreational drug use or with symptoms/signs consistent with acute toxicity. Isolated ethanol intoxications were excluded. Intoxications were confirmed with immunoassa...

  19. A novel family of DG methods for diffusion problems

    Science.gov (United States)

    Johnson, Philip; Johnsen, Eric

    2017-11-01

    We describe and demonstrate a novel family of numerical schemes for handling elliptic/parabolic PDE behavior within the discontinuous Galerkin (DG) framework. Starting from the mixed-form approach commonly applied for handling diffusion (examples include Local DG and BR2), the new schemes apply the Recovery concept of Van Leer to handle cell interface terms. By applying recovery within the mixed-form approach, we have designed multiple schemes that show better accuracy than other mixed-form approaches while being more flexible and easier to implement than the Recovery DG schemes of Van Leer. While typical mixed-form approaches converge at rate 2p in the cell-average or functional error norms (where p is the order of the solution polynomial), many of our approaches achieve order 2p +2 convergence. In this talk, we will describe multiple schemes, including both compact and non-compact implementations; the compact approaches use only interface-connected neighbors to form the residual for each element, while the non-compact approaches add one extra layer to the stencil. In addition to testing the schemes on purely parabolic PDE problems, we apply them to handle the diffusive flux terms in advection-diffusion systems, such as the compressible Navier-Stokes equations.

  20. Strategies to facilitate integrated care for people with alcohol and other drug problems: a systematic review.

    Science.gov (United States)

    Savic, Michael; Best, David; Manning, Victoria; Lubman, Dan I

    2017-04-07

    There is a growing body of research highlighting the potential benefits of integrated care as a way of addressing the needs of people with alcohol and other drug (AOD) problems, given the broad range of other issues clients often experience. However, there has been little academic attention on the strategies that treatment systems, agencies and clinicians could implement to facilitate integrated care. We synthesised the existing evidence on strategies to improve integrated care in an AOD treatment context by conducting a systematic review of the literature. We searched major academic databases for peer-reviewed articles that evaluated strategies that contribute to integrated care in an AOD context between 1990 and 2014. Over 2600 articles were identified, of which 14 met the study inclusion criteria of reporting on an empirical study to evaluate the implementation of integrated care strategies. The types of strategies utilised in included articles were then synthesised. We identified a number of interconnected strategies at the funding, organisational, service delivery and clinical levels. Ensuring that integrated care is included within service specifications of commissioning bodies and is adequately funded was found to be critical in effective integration. Cultivating positive inter-agency relationships underpinned and enabled the implementation of most strategies identified. Staff training in identifying and responding to needs beyond clinicians' primary area of expertise was considered important at a service level. However, some studies highlight the need to move beyond discrete training events and towards longer term coaching-type activities focussed on implementation and capacity building. Sharing of client information (subject to informed consent) was critical for most integrated care strategies. Case-management was found to be a particularly good approach to responding to the needs of clients with multiple and complex needs. At the clinical level, screening

  1. Numerical Methods for Forward and Inverse Problems in Discontinuous Media

    Energy Technology Data Exchange (ETDEWEB)

    Chartier, Timothy P.

    2011-03-08

    The research emphasis under this grant's funding is in the area of algebraic multigrid methods. The research has two main branches: 1) exploring interdisciplinary applications in which algebraic multigrid can make an impact and 2) extending the scope of algebraic multigrid methods with algorithmic improvements that are based in strong analysis.The work in interdisciplinary applications falls primarily in the field of biomedical imaging. Work under this grant demonstrated the effectiveness and robustness of multigrid for solving linear systems that result from highly heterogeneous finite element method models of the human head. The results in this work also give promise to medical advances possible with software that may be developed. Research to extend the scope of algebraic multigrid has been focused in several areas. In collaboration with researchers at the University of Colorado, Lawrence Livermore National Laboratory, and Los Alamos National Laboratory, the PI developed an adaptive multigrid with subcycling via complementary grids. This method has very cheap computing costs per iterate and is showing promise as a preconditioner for conjugate gradient. Recent work with Los Alamos National Laboratory concentrates on developing algorithms that take advantage of the recent advances in adaptive multigrid research. The results of the various efforts in this research could ultimately have direct use and impact to researchers for a wide variety of applications, including, astrophysics, neuroscience, contaminant transport in porous media, bi-domain heart modeling, modeling of tumor growth, and flow in heterogeneous porous media. This work has already led to basic advances in computational mathematics and numerical linear algebra and will continue to do so into the future.

  2. Fast Implicit Methods For Elliptic Moving Interface Problems

    Science.gov (United States)

    2015-12-11

    surfaces [30], and has recently been employed in the geometric nonuniform fast Fourier transform [12] and in the finite element method [31]. We employ...analyzed, and tested for the Fourier transform of piecewise polynomials given on d-dimensional simplices in D-dimensional Euclidean space. These transforms ...evaluation, and one to three orders of magnitude slower than the classical uniform Fast Fourier Transform . Second, bilinear quadratures ---which

  3. The Method of Lines for Ternary Diffusion Problems

    Directory of Open Access Journals (Sweden)

    Henryk Leszczyński

    2014-01-01

    Full Text Available The method of lines (MOL for diffusion equations with Neumann boundary conditions is considered. These equations are transformed by a discretization in space variables into systems of ordinary differential equations. The proposed ODEs satisfy the mass conservation law. The stability of solutions of these ODEs with respect to discrete L2 norms and discrete W1,∞ norms is investigated. Numerical examples confirm the parabolic behaviour of this model and very regular dynamics.

  4. Analysis of Diffusion Problems using Homotopy Perturbation and Variational Iteration Methods

    DEFF Research Database (Denmark)

    Barari, Amin; Poor, A. Tahmasebi; Jorjani, A.

    2010-01-01

    In this paper, variational iteration method and homotopy perturbation method are applied to different forms of diffusion equation. The diffusion equations have found wide applications in heat transfer problems, theory of consolidation and many other problems in engineering. The methods proposed...

  5. Convergence of Inner-Iteration GMRES Methods for Rank-Deficient Least Squares Problems

    Czech Academy of Sciences Publication Activity Database

    Morikuni, Keiichi; Hayami, K.

    2015-01-01

    Roč. 36, č. 1 (2015), s. 225-250 ISSN 0895-4798 Institutional support: RVO:67985807 Keywords : least squares problem * iterative methods * preconditioner * inner-outer iteration * GMRES method * stationary iterative method * rank-deficient problem Subject RIV: BA - General Mathematics Impact factor: 1.883, year: 2015

  6. An analysis of the Six Sigma DMAIC method from the perspective of problem solving

    NARCIS (Netherlands)

    de Mast, J.; Lokkerbol, J.

    2012-01-01

    The DMAIC (Define-Measure-Analyze-Improve-Control) method in Six Sigma is often described as an approach for problem solving. This paper compares critically the DMAIC method with insights from scientific theories in the field of problem solving. As a single authoritative account of the DMAIC method

  7. In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts

    Science.gov (United States)

    Yang, Hongbin; Sun, Lixia; Li, Weihua; Liu, Guixia; Tang, Yun

    2018-02-01

    For a drug, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

  8. In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts

    Directory of Open Access Journals (Sweden)

    Hongbin Yang

    2018-02-01

    Full Text Available During drug development, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

  9. In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts.

    Science.gov (United States)

    Yang, Hongbin; Sun, Lixia; Li, Weihua; Liu, Guixia; Tang, Yun

    2018-01-01

    During drug development, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

  10. A Promising New Method to Estimate Drug-Polymer Solubility at Room Temperature

    DEFF Research Database (Denmark)

    Knopp, Matthias Manne; Gannon, Natasha; Porsch, Ilona

    2016-01-01

    The established methods to predict drug-polymer solubility at room temperature either rely on extrapolation over a long temperature range or are limited by the availability of a liquid analogue of the polymer. To overcome these issues, this work investigated a new methodology where the drug-polymer...... solubility is estimated from the solubility of the drug in a solution of the polymer at room temperature using the shake-flask method. Thus, the new polymer in solution method does not rely on temperature extrapolations and only requires the polymer and a solvent, in which the polymer is soluble, that does...... not affect the molecular structure of the drug and polymer relative to that in the solid state. Consequently, as this method has the potential to provide fast and precise estimates of drug-polymer solubility at room temperature, we encourage the scientific community to further investigate this principle both...

  11. Heuristics methods for the flow shop scheduling problem with separated setup times

    Directory of Open Access Journals (Sweden)

    Marcelo Seido Nagano

    2012-06-01

    Full Text Available This paper deals with the permutation flow shop scheduling problem with separated machine setup times. As a result of an investigation on the problem characteristics, four heuristics methods are proposed with procedures of the construction sequencing solution by an analogy with the asymmetric traveling salesman problem with the objective of minimizing makespan. Experimental results show that one of the new heuristics methods proposed provide high quality solutions in comparisons with the evaluated methods considered in the literature.

  12. An algebraic method to solve the Tavis-Cummings problem

    International Nuclear Information System (INIS)

    Vadejko, I.P.; Miroshnichenko, G.P.; Rybin, A.V.; Timonen, J.

    2003-01-01

    We study cooperative behaviour of the system of two-level atoms coupled to a single mode of the electromagnetic field in the resonator. We have developed a general procedure allowing one to rewrite a polynomial deformed SU(2) algebra in terms of another polynomial deformation. Using these methods, we have constructed a perturbation series for the Tavis-Cummings Hamiltonian and diagonalized it in the third order. Based on the zero-order Hamiltonian we calculate the intensity of spontaneous emission of N two-level atoms inside a cavity, which are in thermal equilibrium with the reservoir. The atom-atom correlation determining superradiance in the system is analyzed

  13. What to Do If Your Adult Friend or Loved One Has a Problem with Drugs

    Science.gov (United States)

    ... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...

  14. What to Do If You Have a Problem with Drugs: For Teens and Young Adults

    Science.gov (United States)

    ... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...

  15. Prosecution's Power, Procedural Rights, and Pleading Guilty: The Problem of Coercion in Plea Bargaining Drug Cases.

    Science.gov (United States)

    Cloyd, Jerald W.

    1979-01-01

    The forms of psychological pressure placed on the defendant's pleading in drug cases are examined, with emphasis on the interplay between rational and emotional aspects of such situations. Three stages in plea bargaining negotiations are outlined. (Author/MC)

  16. Development of modelling method selection tool for health services management: from problem structuring methods to modelling and simulation methods.

    Science.gov (United States)

    Jun, Gyuchan T; Morris, Zoe; Eldabi, Tillal; Harper, Paul; Naseer, Aisha; Patel, Brijesh; Clarkson, John P

    2011-05-19

    There is an increasing recognition that modelling and simulation can assist in the process of designing health care policies, strategies and operations. However, the current use is limited and answers to questions such as what methods to use and when remain somewhat underdeveloped. The aim of this study is to provide a mechanism for decision makers in health services planning and management to compare a broad range of modelling and simulation methods so that they can better select and use them or better commission relevant modelling and simulation work. This paper proposes a modelling and simulation method comparison and selection tool developed from a comprehensive literature review, the research team's extensive expertise and inputs from potential users. Twenty-eight different methods were identified, characterised by their relevance to different application areas, project life cycle stages, types of output and levels of insight, and four input resources required (time, money, knowledge and data). The characterisation is presented in matrix forms to allow quick comparison and selection. This paper also highlights significant knowledge gaps in the existing literature when assessing the applicability of particular approaches to health services management, where modelling and simulation skills are scarce let alone money and time. A modelling and simulation method comparison and selection tool is developed to assist with the selection of methods appropriate to supporting specific decision making processes. In particular it addresses the issue of which method is most appropriate to which specific health services management problem, what the user might expect to be obtained from the method, and what is required to use the method. In summary, we believe the tool adds value to the scarce existing literature on methods comparison and selection.

  17. Numerical Investigations on Several Stabilized Finite Element Methods for the Stokes Eigenvalue Problem

    Directory of Open Access Journals (Sweden)

    Pengzhan Huang

    2011-01-01

    Full Text Available Several stabilized finite element methods for the Stokes eigenvalue problem based on the lowest equal-order finite element pair are numerically investigated. They are penalty, regular, multiscale enrichment, and local Gauss integration method. Comparisons between them are carried out, which show that the local Gauss integration method has good stability, efficiency, and accuracy properties, and it is a favorite method among these methods for the Stokes eigenvalue problem.

  18. Employee assistance program services for alcohol and other drug problems: implications for increased identification and engagement in treatment.

    Science.gov (United States)

    Jacobson, Jodi M; Sacco, Paul

    2012-01-01

    Fourteen million U.S. workers meet the diagnostic criteria for substance dependence, costing millions in lost productivity. Prior research suggests that employees who follow through with their Employee Assistance Program's (EAP) recommendations are more likely to participate and remain engaged in alcohol and other drug (AOD) treatment programs. This study identified rates of lifetime EAP service use for AOD problems and compared adults who reported using EAP services for AOD problems with those who used services other than EAP. Researchers analyzed a subset of participants from the National Epidemiologic Survey of Alcohol and Related Conditions who reported having received help for an AOD problem (NESARC, 2001-2002). Statistical analyses tested for differences in sociodemographic variables, lifetime mental health and substance abuse disorders, and health disability between EAP services users and users of other types of services. Among adults who sought services for AOD problems (n= 2,272), 7.58% (n= 166) reported using EAP services for these problems at some point during their lives. Major depressive disorder (lifetime), a drug use disorder (lifetime), and Black race/ethnicity were associated with a greater likelihood that someone would seek EAP services for help with their AOD problem. Results provide a foundation for researchers to understand who uses EAP services for AOD problems. Health and mental health professionals should increase their knowledge of EAP services to improve continuity of care for employees with AOD problems. EAPs are in a unique position to reach out to vulnerable employees in the workplace and engage them in treatment. Copyright © American Academy of Addiction Psychiatry.

  19. Knowledge of Male High School Students in Yazd and Rafsanjan (IRAN Regarding Illicit Drugs Use as a Social Problem: A comparative study

    Directory of Open Access Journals (Sweden)

    Zahra Pourmovahed

    2017-06-01

    Conclusion: Illicit drugs consumption remains a serious problem among Iranian adolescents. There is the need to implement preventive measures and counselling approaches in schools. Regarding the role of an addict in the family, increasing the knowledge of people about the negative effects of drugs use (especially opiates might lead to the better prevention of this social problem and promotion of health.

  20. Analytical methods and problems for the diamides type of extractants

    International Nuclear Information System (INIS)

    Cuillerdier, C.; Nigond, L.; Musikas, C.; Vitart, H.; Hoel, P.

    1989-01-01

    Diamides of carboxylic acids and especially malonamides are able to extract alpha emitters (including trivalent ions such as Am and Cm) contained in the wastes solutions of the nuclear industry. As they are completely incinerable and easy to purify, they could be an alternative to the mixture CMPO-TBP which is used in the TRUEX process. A large oxyalkyl radical enhances the distribution coefficients of americium in nitric acid sufficiently to permit the decontamination of wastes solutions in a classical mixers-settlers battery. Now researches are pursued with the aim of optimizing the formula of extractant, the influence of the structure of the extractant on its basicity and stability under radiolysis and hydrolysis is investigated. Analytical methods (potentiometry and NMR of C 13 ) have been developed for solvent titration and to evaluate the percentage of degradation and to identify some of the degradation products

  1. Methods for measuring denitrification: Diverse approaches to a difficult problem

    DEFF Research Database (Denmark)

    Groffman, Peter M.; Altabet, Mark A.; Böhlke, J. K.

    2006-01-01

    , and global scales. Unfortunately, this process is very difficult to measure, and existing methods are problematic for different reasons in different places at different times. In this paper, we review the major approaches that have been taken to measure denitrification in terrestrial and aquatic environments...... based on stable isotopes, (8) in situ gradients with atmospheric environmental tracers, and (9) molecular approaches. Our review makes it clear that the prospects for improved quantification of denitrification vary greatly in different environments and at different scales. While current methodology allows...... for the production of accurate estimates of denitrification at scales relevant to water and air quality and ecosystem fertility questions in some systems (e.g., aquatic sediments, well-defined aquifers), methodology for other systems, especially upland terrestrial areas, still needs development. Comparison of mass...

  2. The role of problem solving method on the improvement of mathematical learning

    Directory of Open Access Journals (Sweden)

    Saeed Mokhtari-Hassanabad

    2012-10-01

    Full Text Available In history of education, problem solving is one of the important educational goals and teachers or parents have intended that their students have capacity of problem solving. In present research, it is tried that study the problem solving method for mathematical learning. This research is implemented via quasi-experimental method on 49 boy students at high school. The results of Leven test and T-test indicated that problem solving method has more effective on the improvement of mathematical learning than traditional instruction method. Therefore it seems that teachers of mathematics must apply the problem solving method in educational systems till students became self-efficiency in mathematical problem solving.

  3. Violent and Non-Violent Criminal Behavior among Young Chinese Drug Users: A Mixed Methods Study.

    Science.gov (United States)

    Liu, Liu; Chui, Wing Hong; Chen, Ye

    2018-03-02

    Young drug users are found to be increasingly involved in criminal justice issues. This exploratory and descriptive study aims to analyze the criminal behaviors among young Chinese drug users through a mixed methods research design. Quantitative analysis indicates that young drug users with and without a history of criminality show significant differences in terms of several features. Male drug users, particularly, those who are older, with religious beliefs, and initiated into drug use at younger age were most likely to commit crimes. Among drug users with criminal experiences, those who committed crimes prior to drug initiation have a greater likelihood of committing violent crimes. Furthermore, young drug users with severe depression are more likely to commit crimes, especially violent ones. Qualitative analysis further illustrates that young male drug users often get involved in criminal conduct of the youth gang nature with propensity for engaging in violent crimes as compared to their female counterparts who are more likely to turn into drug dealers and traffickers, in addition to engaging in larceny. The research findings are consistent with developmental theories and "victim to offender cycle". Integrated mental health and substance use services are suggested for crime prevention among young Chinese drug users.

  4. Peer substance use associated with the co-occurrence of borderline personality disorder features and drug use problems in college students.

    Science.gov (United States)

    Pizzarello, Scott; Taylor, Jeanette

    2011-01-01

    To determine if the substance use patterns of one's close friends and romantic partners would be a significant contributor to the co-occurrence of borderline personality disorder (BPD) features and drug use problems above and beyond impulsivity and negative emotionality. Participants were 2,202 undergraduates who attended a large southeastern university between 2003 and 2006. All subjects completed measures assessing the presence of BPD symptoms, drug use problems, general personality traits, and the proportion of their friends and partners who had used illicit drugs within the past 12 months. The illicit drug use patterns of one's friends and romantic partners was a significant contributor to the co-occurrence of BPD features and drug use problems even when controlling for levels of impulsivity and negative emotionality. These findings suggest possible additional avenues for treatment focusing on helping students with BPD and drug use problems modify their social group.

  5. Evolution of the concept of drug-related problems: outcomes as the focus / Evolución del concepto de problemas relacionados con medicamentos:resultados como el centro del nuevo paradigma

    Directory of Open Access Journals (Sweden)

    Fernandez-Llimos F

    2005-12-01

    Full Text Available Objective: To review the concept of drug-related problems and drug therapy problems, and its relationship with other concepts, like medication negative outcomes.Methods: Primary articles were identified through a MEDLINE search (1966 to September 2004; reference cites from the articles found provided additional resource material. Retrieved and selected papers were reviewed and relevant information was included.Results: the term drug-related problem has been widely used in literature, not always representing a simple concept. Process (causes and outcomes (effects had been mixed under different DRP definitions and classifications. Drug therapy problems, medicine-related problems and medication related problems are other terms used to define the same unclear concept. The idea of actual and potential problems was created to act on preventing the effect of these problems. This paper suggests the use of commonly accepted biomedical terms, and put these concepts into recognized models and paradigms (namely, SPO and ECHO. Also the name of medication negative clinical outcomes is proposed.Conclusions: Any medication negative clinical outcome can be assigned to a single definition and classification. A Systematic identification tool has been shown to be effective in detecting each and every one of the negative clinical outcomes in patient pharmacotherapy.

  6. Linked-Class Problem-Based Learning in Engineering: Method and Evaluation

    Science.gov (United States)

    Hunt, Emily M.; Lockwood-Cooke, Pamela; Kelley, Judy

    2010-01-01

    Problem-Based Learning (PBL) is a problem-centered teaching method with exciting potential in engineering education for motivating and enhancing student learning. Implementation of PBL in engineering education has the potential to bridge the gap between theory and practice. Two common problems are encountered when attempting to integrate PBL into…

  7. Recursive-operator method in vibration problems for rod systems

    Science.gov (United States)

    Rozhkova, E. V.

    2009-12-01

    Using linear differential equations with constant coefficients describing one-dimensional dynamical processes as an example, we show that the solutions of these equations and systems are related to the solution of the corresponding numerical recursion relations and one does not have to compute the roots of the corresponding characteristic equations. The arbitrary functions occurring in the general solution of the homogeneous equations are determined by the initial and boundary conditions or are chosen from various classes of analytic functions. The solutions of the inhomogeneous equations are constructed in the form of integro-differential series acting on the right-hand side of the equation, and the coefficients of the series are determined from the same recursion relations. The convergence of formal solutions as series of a more general recursive-operator construction was proved in [1]. In the special case where the solutions of the equation can be represented in separated variables, the power series can be effectively summed, i.e., expressed in terms of elementary functions, and coincide with the known solutions. In this case, to determine the natural vibration frequencies, one obtains algebraic rather than transcendental equations, which permits exactly determining the imaginary and complex roots of these equations without using the graphic method [2, pp. 448-449]. The correctness of the obtained formulas (differentiation formulas, explicit expressions for the series coefficients, etc.) can be verified directly by appropriate substitutions; therefore, we do not prove them here.

  8. Methods for the integral assessment of energy-related problems

    International Nuclear Information System (INIS)

    Hirschberg, S.; Suter, P.

    1995-01-01

    The present paper presents a number of methods for a comprehensive assessment of energy systems, discusses their merits and limitations, and provides some result examples. The areas addressed include environmental impacts, risks and economic aspects. Three step Life Cycle Analysis (LCA) has been used to analyse environmental impacts. Transparent and consistent inventories were developed for electricity generation (nine fuel cycles) and for heating systems. The results, which include gaseous and liquid emissions as well as non-energetic resources such as land depreciation, cover average, currently operating systems in the UCPTE network and in Switzerland. Examples of comparisons of heating systems and electricity generation systems, with respect to their contributions to such impact classes as greenhouse effect, acidification and photosmog, are provided. Major gaps exist with respect to the assessment of the severe accidents potential within the different energy systems. When analysing the objective risks due to severe accidents two approaches are employed, i.e. direct use of past experience and applications of Probabilistic Safety Assessment (PSA). Progress with respect to extended knowledge about accidents that occurred in the past and in the context of uses of PSA for external costs calculations is reported. Limitations of historical data and modelling issues are discussed along with the role of risk aversion and current attempts to account for it. (author) 10 figs., 1 tab

  9. Iterative observer based method for source localization problem for Poisson equation in 3D

    KAUST Repository

    Majeed, Muhammad Usman

    2017-07-10

    A state-observer based method is developed to solve point source localization problem for Poisson equation in a 3D rectangular prism with available boundary data. The technique requires a weighted sum of solutions of multiple boundary data estimation problems for Laplace equation over the 3D domain. The solution of each of these boundary estimation problems involves writing down the mathematical problem in state-space-like representation using one of the space variables as time-like. First, system observability result for 3D boundary estimation problem is recalled in an infinite dimensional setting. Then, based on the observability result, the boundary estimation problem is decomposed into a set of independent 2D sub-problems. These 2D problems are then solved using an iterative observer to obtain the solution. Theoretical results are provided. The method is implemented numerically using finite difference discretization schemes. Numerical illustrations along with simulation results are provided.

  10. Generalized multivalued equilibrium-like problems: auxiliary principle technique and predictor-corrector methods

    Directory of Open Access Journals (Sweden)

    Vahid Dadashi

    2016-02-01

    Full Text Available Abstract This paper is dedicated to the introduction a new class of equilibrium problems named generalized multivalued equilibrium-like problems which includes the classes of hemiequilibrium problems, equilibrium-like problems, equilibrium problems, hemivariational inequalities, and variational inequalities as special cases. By utilizing the auxiliary principle technique, some new predictor-corrector iterative algorithms for solving them are suggested and analyzed. The convergence analysis of the proposed iterative methods requires either partially relaxed monotonicity or jointly pseudomonotonicity of the bifunctions involved in generalized multivalued equilibrium-like problem. Results obtained in this paper include several new and known results as special cases.

  11. Invisibility problem in acoustics, electromagnetism and heat transfer. Inverse design method

    Science.gov (United States)

    Alekseev, G.; Tokhtina, A.; Soboleva, O.

    2017-10-01

    Two approaches (direct design and inverse design methods) for solving problems of designing devices providing invisibility of material bodies of detection using different physical fields - electromagnetic, acoustic and static are discussed. The second method is applied for solving problems of designing cloaking devices for the 3D stationary thermal scattering model. Based on this method the design problems under study are reduced to respective control problems. The material parameters (radial and tangential heat conductivities) of the inhomogeneous anisotropic medium filling the thermal cloak and the density of auxiliary heat sources play the role of controls. A unique solvability of direct thermal scattering problem in the Sobolev space is proved and the new estimates of solutions are established. Using these results, the solvability of control problem is proved and the optimality system is derived. Based on analysis of optimality system, the stability estimates of optimal solutions are established and numerical algorithms for solving particular thermal cloaking problem are proposed.

  12. Molecular detection methods of resistance to antituberculosis drugs in Mycobacterium tuberculosis.

    Science.gov (United States)

    Brossier, F; Sougakoff, W

    2017-09-01

    Molecular methods predict drug resistance several weeks before phenotypic methods and enable rapid implementation of appropriate therapeutic treatment. We aimed to detail the most representative molecular tools used in routine practice for the rapid detection of resistance to antituberculosis drugs among Mycobacterium tuberculosis strains. The molecular diagnosis of resistance to antituberculosis drugs in clinical samples or from in vitro cultures is based on the detection of the most common mutations in the genes involved in the development of resistance in M. tuberculosis strains (encoding either protein targets of antibiotics, or antibiotic activating enzymes) by commercial molecular kits or by sequencing. Three hypotheses could explain the discrepancies between the genotypic results and the phenotypic drug susceptibility testing results: a low percentage of resistant mutants precluding the detection by genotypic methods on the primary culture; a low level of resistance not detected by phenotypic testing; and other resistance mechanisms not yet characterized. Molecular methods have varying sensitivity with regards to detecting antituberculosis drug resistance; that is why phenotypic susceptibility testing methods are mandatory for detecting antituberculosis drug-resistant isolates that have not been detected by molecular methods. The questionable ability of existing phenotypic and genotypic drug susceptibility testing to properly classify strains as susceptible or resistant, and at what level of resistance, was raised for several antituberculosis agents. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. CLSM as quantitative method to determine the size of drug crystals in a solid dispersion

    NARCIS (Netherlands)

    de Waard, Hans; Hessels, Martin J T; Boon, Maarten; Sjollema, Klaas A; Hinrichs, Wouter L J; Eissens, Anko C; Frijlink, Henderik W

    2011-01-01

    PURPOSE: To test whether confocal laser scanning microscopy (CLSM) can be used as an analytical tool to determine the drug crystal size in a powder mixture or a crystalline solid dispersion. METHODS: Crystals of the autofluorescent drug dipyridamole were incorporated in a matrix of crystalline

  14. An asymptotic analytical solution to the problem of two moving boundaries with fractional diffusion in one-dimensional drug release devices

    International Nuclear Information System (INIS)

    Yin Chen; Xu Mingyu

    2009-01-01

    We set up a one-dimensional mathematical model with a Caputo fractional operator of a drug released from a polymeric matrix that can be dissolved into a solvent. A two moving boundaries problem in fractional anomalous diffusion (in time) with order α element of (0, 1] under the assumption that the dissolving boundary can be dissolved slowly is presented in this paper. The two-parameter regular perturbation technique and Fourier and Laplace transform methods are used. A dimensionless asymptotic analytical solution is given in terms of the Wright function

  15. The cell method for electrical engineering and multiphysics problems an introduction

    CERN Document Server

    Alotto, Piergiorgio; Repetto, Maurizio; Rosso, Carlo

    2013-01-01

    This book presents a numerical scheme for the solution of field problems governed by partial differential equations: the cell method. The technique lends itself naturally to the solution of multiphysics problems with several interacting phenomena. The Cell Method, based on a space-time tessellation, is intimately related to the work of Tonti and to his ideas of classification diagrams or, as they are nowadays called, Tonti diagrams: a graphical representation of the problem's equations made possible by a suitable selection of a space-time framework relating physical variables to each other. The main features of the cell method are presented and links with many other discrete numerical methods (finite integration techniques, finite difference time domain, finite volumes, mimetic finite differences, etc.) are discussed. After outlining the theoretical basis of the method, a set of physical problems which have been solved with the cell method is described. These single and multiphysics problems stem from the aut...

  16. Proximal Alternating Direction Method with Relaxed Proximal Parameters for the Least Squares Covariance Adjustment Problem

    Directory of Open Access Journals (Sweden)

    Minghua Xu

    2014-01-01

    Full Text Available We consider the problem of seeking a symmetric positive semidefinite matrix in a closed convex set to approximate a given matrix. This problem may arise in several areas of numerical linear algebra or come from finance industry or statistics and thus has many applications. For solving this class of matrix optimization problems, many methods have been proposed in the literature. The proximal alternating direction method is one of those methods which can be easily applied to solve these matrix optimization problems. Generally, the proximal parameters of the proximal alternating direction method are greater than zero. In this paper, we conclude that the restriction on the proximal parameters can be relaxed for solving this kind of matrix optimization problems. Numerical experiments also show that the proximal alternating direction method with the relaxed proximal parameters is convergent and generally has a better performance than the classical proximal alternating direction method.

  17. ANALYSIS AND PERFORMANCE MEASUREMENT OF EXISTING SOLUTION METHODS OF QUADRATIC ASSIGNMENT PROBLEM

    Directory of Open Access Journals (Sweden)

    Morteza KARAMI

    2014-01-01

    Full Text Available Quadratic Assignment Problem (QAP is known as one of the most difficult combinatorial optimization problems that is classified in the category of NP-hard problems. Quadratic Assignment Problem Library (QAPLIB is a full database of QAPs which contains several problems from different authors and different sizes. Many exact and meta-heuristic solution methods have been introduced to solve QAP. In this study we focus on previously introduced solution methods of QAP e.g. Branch and Bound (B&B, Simulated Annealing (SA Algorithm, Greedy Randomized Adaptive Search Procedure (GRASP for dense and sparse QAPs. The codes of FORTRAN for these methods were downloaded from QAPLIB. All problems of QAPLIB were solved by the abovementioned methods. Several results were obtained from the computational experiments part. The Results show that the Branch and Bound method is able to introduce a feasible solution for all problems while Simulated Annealing Algorithm and GRASP methods are not able to find any solution for some problems. On the other hand, Simulated Annealing and GRASP methods have shorter run time comparing to the Branch and Bound method. In addition, the performance of the methods on the objective function value is discussed.

  18. Extending the subspace hybrid method for eigenvalue problems in reactor physics calculation

    International Nuclear Information System (INIS)

    Zhang, Q.; Abdel-Khalik, H. S.

    2013-01-01

    This paper presents an innovative hybrid Monte-Carlo-Deterministic method denoted by the SUBSPACE method designed for improving the efficiency of hybrid methods for reactor analysis applications. The SUBSPACE method achieves its high computational efficiency by taking advantage of the existing correlations between desired responses. Recently, significant gains in computational efficiency have been demonstrated using this method for source driven problems. Within this work the mathematical theory behind the SUBSPACE method is introduced and extended to address core wide level k-eigenvalue problems. The method's efficiency is demonstrated based on a three-dimensional quarter-core problem, where responses are sought on the pin cell level. The SUBSPACE method is compared to the FW-CADIS method and is found to be more efficient for the utilized test problem because of the reason that the FW-CADIS method solves a forward eigenvalue problem and an adjoint fixed-source problem while the SUBSPACE method only solves an adjoint fixed-source problem. Based on the favorable results obtained here, we are confident that the applicability of Monte Carlo for large scale reactor analysis could be realized in the near future. (authors)

  19. Drug-related problems identification in general internal medicine: The impact and role of the clinical pharmacist and pharmacologist.

    Science.gov (United States)

    Guignard, Bertrand; Bonnabry, Pascal; Perrier, Arnaud; Dayer, Pierre; Desmeules, Jules; Samer, Caroline Flora

    2015-07-01

    Patients admitted to general internal medicine wards might receive a large number of drugs and be at risk for drug-related problems (DRPs) associated with increased morbidity and mortality. This study aimed to detect suboptimal drug use in internal medicine by a pharmacotherapy evaluation, to suggest treatment optimizations and to assess the acceptance and satisfaction of the prescribers. This was a 6-month prospective study conducted in two internal medicine wards. Physician rounds were attended by a pharmacist and a pharmacologist. An assessment grid was used to detect the DRPs in electronic prescriptions 24h in advance. One of the following interventions was selected, depending on the relevance and complexity of the DRPs: no intervention, verbal advice of treatment optimization, or written consultation. The acceptance rate and satisfaction of prescribers were measured. In total, 145 patients were included, and 383 DRPs were identified (mean: 2.6 DRPs per patient). The most frequent DRPs were drug interactions (21%), untreated indications (18%), overdosages (16%) and drugs used without a valid indication (10%). The drugs or drug classes most frequently involved were tramadol, antidepressants, acenocoumarol, calcium-vitamin D, statins, aspirin, proton pump inhibitors and paracetamol. The following interventions were selected: no intervention (51%), verbal advice of treatment optimization (42%), and written consultation (7%). The acceptance rate of prescribers was 84% and their satisfaction was high. Pharmacotherapy expertise during medical rounds was useful and well accepted by prescribers. Because of the modest allocation of pharmacists and pharmacologists in Swiss hospitals, complementary strategies would be required. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  20. Nitsche's method for interface problems in computational mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Hansbo, P. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Applied Mechanics

    2005-07-01

    We give a review of Nitsche's method applied to interface problems, involving real or artificial interfaces. Applications to unfitted meshes, Chimera meshes, cut meshes, fictitious domain methods, and model coupling are discussed. (orig.)

  1. On the Inclusion of Difference Equation Problems and Z Transform Methods in Sophomore Differential Equation Classes

    Science.gov (United States)

    Savoye, Philippe

    2009-01-01

    In recent years, I started covering difference equations and z transform methods in my introductory differential equations course. This allowed my students to extend the "classical" methods for (ordinary differential equation) ODE's to discrete time problems arising in many applications.

  2. Applications of the infinite momentum method to quantum electrodynamics and bound state problem

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1973-01-01

    It is shown that the infinite momentum method is a valid and useful calculational alternative to standard perturbation theory methods. The most exciting future applications may be in bound state problems in quantum electrodynamics

  3. Drug Abuse

    Science.gov (United States)

    ... Cocaine Heroin Inhalants Marijuana Prescription drugs, including opioids Drug abuse also plays a role in many major social problems, such as drugged driving, violence, stress, and child abuse. Drug abuse can lead to ...

  4. Drug Facts

    Medline Plus

    Full Text Available ... Use and Unborn Children Drug Use and Your Health Other Effects on the Body Drug Use Hurts Brains Drug Use and Mental Health Problems Often Happen Together The Link Between Drug ...

  5. A restricted Steiner tree problem is solved by Geometric Method II

    Science.gov (United States)

    Lin, Dazhi; Zhang, Youlin; Lu, Xiaoxu

    2013-03-01

    The minimum Steiner tree problem has wide application background, such as transportation system, communication network, pipeline design and VISL, etc. It is unfortunately that the computational complexity of the problem is NP-hard. People are common to find some special problems to consider. In this paper, we first put forward a restricted Steiner tree problem, which the fixed vertices are in the same side of one line L and we find a vertex on L such the length of the tree is minimal. By the definition and the complexity of the Steiner tree problem, we know that the complexity of this problem is also Np-complete. In the part one, we have considered there are two fixed vertices to find the restricted Steiner tree problem. Naturally, we consider there are three fixed vertices to find the restricted Steiner tree problem. And we also use the geometric method to solve such the problem.

  6. A multilevel, level-set method for optimizing eigenvalues in shape design problems

    International Nuclear Information System (INIS)

    Haber, E.

    2004-01-01

    In this paper, we consider optimal design problems that involve shape optimization. The goal is to determine the shape of a certain structure such that it is either as rigid or as soft as possible. To achieve this goal we combine two new ideas for an efficient solution of the problem. First, we replace the eigenvalue problem with an approximation by using inverse iteration. Second, we use a level set method but rather than propagating the front we use constrained optimization methods combined with multilevel continuation techniques. Combining these two ideas we obtain a robust and rapid method for the solution of the optimal design problem

  7. New homotopy analysis transform method for solving the discontinued problems arising in nanotechnology

    International Nuclear Information System (INIS)

    Khader, M. M.; Kumar, Sunil; Abbasbandy, S.

    2013-01-01

    We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential—difference equations. The proposed method is based on the Laplace transform with the homotopy analysis method (HAM). This method is a powerful tool for solving a large amount of problems. This technique provides a series of functions which may converge to the exact solution of the problem. A good agreement between the obtained solution and some well-known results is obtained

  8. On the Application of Iterative Methods of Nondifferentiable Optimization to Some Problems of Approximation Theory

    Directory of Open Access Journals (Sweden)

    Stefan M. Stefanov

    2014-01-01

    Full Text Available We consider the data fitting problem, that is, the problem of approximating a function of several variables, given by tabulated data, and the corresponding problem for inconsistent (overdetermined systems of linear algebraic equations. Such problems, connected with measurement of physical quantities, arise, for example, in physics, engineering, and so forth. A traditional approach for solving these two problems is the discrete least squares data fitting method, which is based on discrete l2-norm. In this paper, an alternative approach is proposed: with each of these problems, we associate a nondifferentiable (nonsmooth unconstrained minimization problem with an objective function, based on discrete l1- and/or l∞-norm, respectively; that is, these two norms are used as proximity criteria. In other words, the problems under consideration are solved by minimizing the residual using these two norms. Respective subgradients are calculated, and a subgradient method is used for solving these two problems. The emphasis is on implementation of the proposed approach. Some computational results, obtained by an appropriate iterative method, are given at the end of the paper. These results are compared with the results, obtained by the iterative gradient method for the corresponding “differentiable” discrete least squares problems, that is, approximation problems based on discrete l2-norm.

  9. A difference quotient-numerical integration method for solving radiative transfer problems

    International Nuclear Information System (INIS)

    Ding Peizhu

    1992-01-01

    A difference quotient-numerical integration method is adopted to solve radiative transfer problems in an anisotropic scattering slab medium. By using the method, the radiative transfer problem is separated into a system of linear algebraic equations and the coefficient matrix of the system is a band matrix, so the method is very simple to evaluate on computer and to deduce formulae and easy to master for experimentalists. An example is evaluated and it is shown that the method is precise

  10. Scaling Professional Problems of Teachers in Turkey with Paired Comparison Method

    Directory of Open Access Journals (Sweden)

    Yasemin Duygu ESEN

    2017-03-01

    Full Text Available In this study, teachers’ professional problems was investigated and the significance level of them was measured with the paired comparison method. The study was carried out in survey model. The study group consisted of 484 teachers working in public schools which are accredited by Ministry of National Education (MEB in Turkey. “The Teacher Professional Problems Survey” developed by the researchers was used as a data collection tool. In data analysis , the scaling method with the third conditional equation of Thurstone’s law of comparative judgement was used. According to the results of study, the teachers’ professional problems include teacher training and the quality of teacher, employee rights and financial problems, decrease of professional reputation, the problems with MEB policies, the problems with union activities, workload, the problems with administration in school, physical conditions and the lack of infrastructure, the problems with parents, the problems with students. According to teachers, the most significant problem is MEB educational policies. This is followed by decrease of professional reputation, physical conditions and the lack of infrastructure, the problems with students, employee rights and financial problems, the problems with administration in school, teacher training and the quality of teacher, the problems with parents, workload, and the problems with union activities. When teachers’ professional problems were analyzed seniority variable, there was little difference in scale values. While the teachers with 0-10 years experience consider decrease of professional reputation as the most important problem, the teachers with 11-45 years experience put the problems with MEB policies at the first place.

  11. Canonical Primal-Dual Method for Solving Non-convex Minimization Problems

    OpenAIRE

    Wu, Changzhi; Li, Chaojie; Gao, David Yang

    2012-01-01

    A new primal-dual algorithm is presented for solving a class of non-convex minimization problems. This algorithm is based on canonical duality theory such that the original non-convex minimization problem is first reformulated as a convex-concave saddle point optimization problem, which is then solved by a quadratically perturbed primal-dual method. %It is proved that the popular SDP method is indeed a special case of the canonical duality theory. Numerical examples are illustrated. Comparing...

  12. Functional geometric method for solving free boundary problems for harmonic functions

    Energy Technology Data Exchange (ETDEWEB)

    Demidov, Aleksander S [M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2010-01-01

    A survey is given of results and approaches for a broad spectrum of free boundary problems for harmonic functions of two variables. The main results are obtained by the functional geometric method. The core of these methods is an interrelated analysis of the functional and geometric characteristics of the problems under consideration and of the corresponding non-linear Riemann-Hilbert problems. An extensive list of open questions is presented. Bibliography: 124 titles.

  13. Solution of 3D inverse scattering problems by combined inverse equivalent current and finite element methods

    International Nuclear Information System (INIS)

    Kılıç, Emre; Eibert, Thomas F.

    2015-01-01

    An approach combining boundary integral and finite element methods is introduced for the solution of three-dimensional inverse electromagnetic medium scattering problems. Based on the equivalence principle, unknown equivalent electric and magnetic surface current densities on a closed surface are utilized to decompose the inverse medium problem into two parts: a linear radiation problem and a nonlinear cavity problem. The first problem is formulated by a boundary integral equation, the computational burden of which is reduced by employing the multilevel fast multipole method (MLFMM). Reconstructed Cauchy data on the surface allows the utilization of the Lorentz reciprocity and the Poynting's theorems. Exploiting these theorems, the noise level and an initial guess are estimated for the cavity problem. Moreover, it is possible to determine whether the material is lossy or not. In the second problem, the estimated surface currents form inhomogeneous boundary conditions of the cavity problem. The cavity problem is formulated by the finite element technique and solved iteratively by the Gauss–Newton method to reconstruct the properties of the object. Regularization for both the first and the second problems is achieved by a Krylov subspace method. The proposed method is tested against both synthetic and experimental data and promising reconstruction results are obtained

  14. Solution of 3D inverse scattering problems by combined inverse equivalent current and finite element methods

    Energy Technology Data Exchange (ETDEWEB)

    Kılıç, Emre, E-mail: emre.kilic@tum.de; Eibert, Thomas F.

    2015-05-01

    An approach combining boundary integral and finite element methods is introduced for the solution of three-dimensional inverse electromagnetic medium scattering problems. Based on the equivalence principle, unknown equivalent electric and magnetic surface current densities on a closed surface are utilized to decompose the inverse medium problem into two parts: a linear radiation problem and a nonlinear cavity problem. The first problem is formulated by a boundary integral equation, the computational burden of which is reduced by employing the multilevel fast multipole method (MLFMM). Reconstructed Cauchy data on the surface allows the utilization of the Lorentz reciprocity and the Poynting's theorems. Exploiting these theorems, the noise level and an initial guess are estimated for the cavity problem. Moreover, it is possible to determine whether the material is lossy or not. In the second problem, the estimated surface currents form inhomogeneous boundary conditions of the cavity problem. The cavity problem is formulated by the finite element technique and solved iteratively by the Gauss–Newton method to reconstruct the properties of the object. Regularization for both the first and the second problems is achieved by a Krylov subspace method. The proposed method is tested against both synthetic and experimental data and promising reconstruction results are obtained.

  15. A variation method in the optimization problem of the minority game model

    International Nuclear Information System (INIS)

    Blazhyijevs'kij, L.; Yanyishevs'kij, V.

    2009-01-01

    This article contains the results of applying a variation method in the investigation of the optimization problem in the minority game model. That suggested approach is shown to give relevant results about phase transition in the model. Other methods pertinent to the problem have also been assessed.

  16. Numerical methods for solution of some nonlinear problems of mathematical physics

    International Nuclear Information System (INIS)

    Zhidkov, E.P.

    1981-01-01

    The continuous analog of the Newton method and its application to some nonlinear problems of mathematical physics using a computer is considered. It is shown that the application of this method in JINR to the wide range of nonlinear problems has shown its universality and high efficiency [ru

  17. To the development of numerical methods in problems of radiation transport

    International Nuclear Information System (INIS)

    Germogenova, T.A.

    1990-01-01

    Review of studies on the development of numerical methods and the discrete ordinate method in particular, used for solution of radiation protection physics problems is given. Consideration is given to the problems, which arise when calculating fields of penetrating radiation and when studying processes of charged-particle transport and cascade processes, generated by high-energy primary radiation

  18. Effective linear two-body method for many-body problems in atomic and nuclear physics

    International Nuclear Information System (INIS)

    Kim, Y.E.; Zubarev, A.L.

    2000-01-01

    We present an equivalent linear two-body method for the many body problem, which is based on an approximate reduction of the many-body Schroedinger equation by the use of a variational principle. The method is applied to several problems in atomic and nuclear physics. (author)

  19. Appling Laplace Adomian decomposition method for delay differential equations with boundary value problems

    Science.gov (United States)

    Yousef, Hamood Mohammed; Ismail, Ahmad Izani

    2017-11-01

    In this paper, Laplace Adomian decomposition method (LADM) was applied to solve Delay differential equations with Boundary Value Problems. The solution is in the form of a convergent series which is easy to compute. This approach is tested on two test problem. The findings obtained exhibit the reliability and efficiency of the proposed method.

  20. Fundamental solution of the problem of linear programming and method of its determination

    Science.gov (United States)

    Petrunin, S. V.

    1978-01-01

    The idea of a fundamental solution to a problem in linear programming is introduced. A method of determining the fundamental solution and of applying this method to the solution of a problem in linear programming is proposed. Numerical examples are cited.

  1. A Smooth Newton Method for Nonlinear Programming Problems with Inequality Constraints

    Directory of Open Access Journals (Sweden)

    Vasile Moraru

    2012-02-01

    Full Text Available The paper presents a reformulation of the Karush-Kuhn-Tucker (KKT system associated nonlinear programming problem into an equivalent system of smooth equations. Classical Newton method is applied to solve the system of equations. The superlinear convergence of the primal sequence, generated by proposed method, is proved. The preliminary numerical results with a problems test set are presented.

  2. The Model Method: Singapore Children's Tool for Representing and Solving Algebraic Word Problems

    Science.gov (United States)

    Ng, Swee Fong; Lee, Kerry

    2009-01-01

    Solving arithmetic and algebraic word problems is a key component of the Singapore elementary mathematics curriculum. One heuristic taught, the model method, involves drawing a diagram to represent key information in the problem. We describe the model method and a three-phase theoretical framework supporting its use. We conducted 2 studies to…

  3. Pretreatment drug use characteristics and experiences among patients in a voluntary substance abuse treatment center in Malaysia: A mixed-methods approach.

    Science.gov (United States)

    Krishnan, Archana; Brown, Shan-Estelle; Ghani, Mansur A; Khan, Farrah; Kamarulzaman, Adeeba; Altice, Frederick L

    2016-01-01

    Drug use in Malaysia remains a significant public health and social problem despite implementation of harsh punitive drug policies such as forcibly placing suspected drug users into compulsory drug detention centers (CDDCs). Following criticism over human right violations in CDDCs, Malaysia has begun to transition towards voluntary drug treatment centers known as Cure & Care (C&C) centers. To best serve the needs of regional C&C centers, data on drug use are essential among patients accessing treatment. Using a mixed-methods approach, the authors examined pretreatment drug use characteristics and experiences with addiction treatment among C&C patients in Kelantan-a religiously conservative state in northeast Malaysia with high prevalence of drug use but where limited data are available on drug use patterns. A mixed-methods study utilizing surveys (n = 96) and semistructured interviews (n = 20) was conducted among a convenience sample of inpatients and outpatients at the Pengkalan Chepa C&C Center in Kelantan. Survey results showed that 89.6% of participants met screening criteria for moderate to severe addiction severity. Nearly 90% reported lifetime illicit amphetamine (syabu, meth, ice, and pil kuda) use, followed by alcohol (60.4%) and opioids (52.1%). Qualitative results pointed to the powerful influence of peer networks in drug initiation and relapse, and the positive effect of the C&C center on drug rehabilitation. The drug use profile of the Kelantan C&C center enrollees shows extensive pretreatment amphetamine use, polysubstance use, and injection drug use, including high-risk behaviors such as sharing needles, syringes, and containers. Evidence points to the need for integration of social support-oriented practices and behavioral interventions into the rehabilitation of drug users in this region.

  4. One Improvement Method of Reducing Duration Directly to Solve Time-Cost Tradeoff Problem

    Science.gov (United States)

    Jian-xun, Qi; Dedong, Sun

    Time and cost are two of the most important factors for project plan and schedule management, and specially, time-cost tradeoff problem is one classical problem in project scheduling, which is also a difficult problem. Methods of solving the problem mainly contain method of network flow and method of mending the minimal cost. Thereinto, for the method of mending the minimal cost is intuitionistic, convenient and lesser computation, these advantages make the method being used widely in practice. But disadvantage of the method is that the result of each step is optimal but the terminal result maybe not optimal. In this paper, firstly, method of confirming the maximal effective quantity of reducing duration is designed; secondly, on the basis of above method and the method of mending the minimal cost, the main method of reducing duration directly is designed to solve time-cost tradeoff problem, and by analyzing validity of the method, the method could obtain more optimal result for the problem.

  5. Human placental perfusion method in the assessment of transplacental passage of antiepileptic drugs

    International Nuclear Information System (INIS)

    Myllynen, Paeivi; Pienimaeki, Paeivi; Vaehaekangas, Kirsi

    2005-01-01

    Epilepsy is one of the most common neurological diseases, affecting about 0.5 to 1% of pregnant women. It is commonly accepted that older antiepileptic drugs bear teratogenic potential. So far, no agreement has been reached about the safest antiepileptic drug during pregnancy. It is known that nearly all drugs cross the placenta at least to some extent. Nowadays, there is very little information available of the pharmacokinetics of drugs in the feto-placental unit. Detailed information about drug transport across the placenta would be valuable for the development of safe and effective treatments. For reasons of safety, human studies on placental transfer are restricted to a limited number of drugs. Interspecies differences limit the extrapolation of animal data to humans. Several in vitro methods for the study of placental transfer have been developed over the past decades. The placental perfusion method is the only experimental method that has been used to study human placental transfer of substances in organized placental tissue. The aim of this article is to review human placental perfusion data on antiepileptic drugs. According to perfusion data, it seems that most of the antiepileptic drugs are transferred across the placenta meaning significant fetal exposure

  6. An introduction to fuzzy linear programming problems theory, methods and applications

    CERN Document Server

    Kaur, Jagdeep

    2016-01-01

    The book presents a snapshot of the state of the art in the field of fully fuzzy linear programming. The main focus is on showing current methods for finding the fuzzy optimal solution of fully fuzzy linear programming problems in which all the parameters and decision variables are represented by non-negative fuzzy numbers. It presents new methods developed by the authors, as well as existing methods developed by others, and their application to real-world problems, including fuzzy transportation problems. Moreover, it compares the outcomes of the different methods and discusses their advantages/disadvantages. As the first work to collect at one place the most important methods for solving fuzzy linear programming problems, the book represents a useful reference guide for students and researchers, providing them with the necessary theoretical and practical knowledge to deal with linear programming problems under uncertainty.

  7. 49 CFR 40.199 - What problems always cause a drug test to be cancelled?

    Science.gov (United States)

    2010-10-01

    ... cancelled? 40.199 Section 40.199 Transportation Office of the Secretary of Transportation PROCEDURES FOR... cause a drug test to be cancelled? (a) As the MRO, when the laboratory discovers a “fatal flaw” during... specimen has been “Rejected for Testing” (with the reason stated). You must always cancel such a test. (b...

  8. Problems Related to Alcohol, Other Drugs, and Violence among Military Students. Prevention Update

    Science.gov (United States)

    Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2011

    2011-01-01

    According to a Research Update from the National Institute on Drug Abuse, ongoing operations in Iraq and Afghanistan "continue to strain military personnel, returning veterans, and their families. Some have experienced long and multiple deployments, combat exposure, and physical injuries, as well as post-traumatic stress disorder (PTSD) and…

  9. Brazil may stop HIV drug access; problems also reported from Argentina.

    Science.gov (United States)

    1999-09-03

    Brazil's financial crisis is threatening its HIV treatment programs, as well as programs for other diseases such as hemophilia, tuberculosis, diabetes, and malaria. The government is expected to stop providing antiretroviral therapy through the public health system in October. Meanwhile, the Argentine government stopped providing antiretroviral medications in August. Drug recycling programs are also discussed. Contact information is provided.

  10. Social Marketing Strategies for Campus Prevention of Alcohol and Other Drug Problems.

    Science.gov (United States)

    Zimmerman, Robert

    This document sets out one segment of a comprehensive approach intended to assist institutions of higher education in developing and carrying out alcohol abuse and other drug prevention programs. Social marketing is described as a tool of environmental management, that seeks to produce a specified behavior in a target audience. Intended for a…

  11. Teenage Pregnancy and Drug Abuse: Sources of Problem Behaviors. ERIC/CUE Digest No. 58.

    Science.gov (United States)

    Bempechat, Janine; And Others

    Drug and alcohol abuse and teenage pregnancy are two behaviors manifested by at-risk children that are both a cause and a result of their lack of success in school and possible subsequent dropping out. The distinction between substance use and abuse may be determined using the following criteria: (1) age of onset; (2) physiological responses; (3)…

  12. Olfactory nerve transport of macromolecular drugs to the brain. A problem in olfactory impaired patients

    International Nuclear Information System (INIS)

    Shiga, Hideaki; Yamamoto, Junpei; Miwa, Takaki

    2012-01-01

    Nasal administration of macromolecular drugs (including peptides and nanoparticles) has the potential to enable drug delivery system beyond the blood brain barrier (BBB) via olfactory nerve transport. Basic research on drug deliver systems to the brain via nasal administration has been well reported. Insulin-like growth factor-I (IGF-I) is associated with the development and growth of the central nervous system. Clinical application of IGF-I with nasal administration is intended to enable drug delivery to brain through the BBB. Uptake of IGF-I in the olfactory bulb and central nervous system increased according to the dosage of nasally administered IGF-I in normal ICR mice, however IGF-I uptake in the trigeminal nerve remained unchanged. Olfactory nerve transport is important for the delivery of nasally administered IGF-I to the brain in vivo. Because a safe olfactory nerve tracer has not been clinically available, olfactory nerve transport has not been well studied in humans. Nasal thallium-201 ( 201 Tl) administration has been safely used to assess the direct pathway to the brain via the nose in healthy volunteers with a normal olfactory threshold. 201 Tl olfactory nerve transport has recently been shown to decrease in patients with hyposmia. The olfactory nerve transport function in patients with olfactory disorders will be determined using 201 Tl olfacto-scintigraphy for the exclusion of candidates in a clinical trial to assess the usefulness of nasal administration of IGF-I. (author)

  13. Cartel Next: How Army Design Methodology Offers Holistic and Dissimilar Approaches to the Mexican Drug Problem

    Science.gov (United States)

    2011-06-30

    which the source is limited to South American regions that grow abundant quantities of the cocoa plant, this cycle manifests in many forms based upon...coffee, bananas, or other legal commodities. In other words, American apathy towards cultural drug consumption often verges on the comical; we

  14. Prescription Drug Abuse: A Fast-Growing Problem | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... have also been reported. Questions to Ask Your Healthcare Provider What is the best way for me to tell if I’m addicted to alcohol and/or drugs? What approach do you suggest I take for my addiction or substance abuse? Do I need to see ...

  15. Evaluation of rapid radiometric method for drug susceptibility testing of Mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Siddiqi, S.H.; Libonati, J.P.; Middlebrook, G.

    1981-01-01

    A total of 106 isolates of Mycobacterium tuberculosis were tested for drug susceptibility by the conventional 7H11 plate method and by a new rapid radiometric method using special 7H12 liquid medium with 14 C-labeled substrate. Results obtained by the two methods were compared for rapidity, sensitivity, and specificity of the new test method. There was 98% overall agreement between the results obtained by the two methods. Of a total of 424 drug tests, only 8 drug results did not agree, mostly in the case of streptomycin. This new procedure was found to be rapid, with 87% of the tests results reportable within 4 days and 98% reportable within 5 days as compared to the usual 3 weeks required with the conventional indirect susceptibility test method. The results of this preliminary study indicate that the rapid radiometric method seems to have the potential for routine laboratory use and merits further investigations

  16. Methods for computing SN eigenvalues and eigenvectors of slab geometry transport problems

    International Nuclear Information System (INIS)

    Yavuz, Musa

    1998-01-01

    We discuss computational methods for computing the eigenvalues and eigenvectors of single energy-group neutral particle transport (S N ) problems in homogeneous slab geometry, with an arbitrary scattering anisotropy of order L. These eigensolutions are important when exact (or very accurate) solutions are desired for coarse spatial cell problems demanding rapid execution times. Three methods, one of which is 'new', are presented for determining the eigenvalues and eigenvectors of such S N problems. In the first method, separation of variables is directly applied to the S N equations. In the second method, common characteristics of the S N and P N-1 equations are used. In the new method, the eigenvalues and eigenvectors can be computed provided that the cell-interface Green's functions (transmission and reflection factors) are known. Numerical results for S 4 test problems are given to compare the new method with the existing methods

  17. Methods for computing SN eigenvalues and eigenvectors of slab geometry transport problems

    International Nuclear Information System (INIS)

    Yavuz, M.

    1997-01-01

    We discuss computational methods for computing the eigenvalues and eigenvectors of single energy-group neutral particle transport (S N ) problems in homogeneous slab geometry, with an arbitrary scattering anisotropy of order L. These eigensolutions are important when exact (or very accurate) solutions are desired for coarse spatial cell problems demanding rapid execution times. Three methods, one of which is 'new', are presented for determining the eigenvalues and eigenvectors of such S N problems. In the first method, separation of variables is directly applied to the S N equations. In the second method, common characteristics of the S N and P N-1 equations are used. In the new method, the eigenvalues and eigenvectors can be computed provided that the cell-interface Green's functions (transmission and reflection factors) are known. Numerical results for S 4 test problems are given to compare the new method with the existing methods. (author)

  18. New implementation method for essential boundary condition to extended element-free Galerkin method. Application to nonlinear problem

    International Nuclear Information System (INIS)

    Saitoh, Ayumu; Matsui, Nobuyuki; Itoh, Taku; Kamitani, Atsushi; Nakamura, Hiroaki

    2011-01-01

    A new method has been proposed for implementing essential boundary conditions to the Element-Free Galerkin Method (EFGM) without using the Lagrange multiplier. Furthermore, the performance of the proposed method has been investigated for a nonlinear Poisson problem. The results of computations show that, as interpolation functions become closer to delta functions, the accuracy of the solution is improved on the boundary. In addition, the accuracy of the proposed method is higher than that of the conventional EFGM. Therefore, it might be concluded that the proposed method is useful for solving the nonlinear Poisson problem. (author)

  19. Iterative Runge–Kutta-type methods for nonlinear ill-posed problems

    International Nuclear Information System (INIS)

    Böckmann, C; Pornsawad, P

    2008-01-01

    We present a regularization method for solving nonlinear ill-posed problems by applying the family of Runge–Kutta methods to an initial value problem, in particular, to the asymptotical regularization method. We prove that the developed iterative regularization method converges to a solution under certain conditions and with a general stopping rule. Some particular iterative regularization methods are numerically implemented. Numerical results of the examples show that the developed Runge–Kutta-type regularization methods yield stable solutions and that particular implicit methods are very efficient in saving iteration steps

  20. Numerical solution of sixth-order boundary-value problems using Legendre wavelet collocation method

    Science.gov (United States)

    Sohaib, Muhammad; Haq, Sirajul; Mukhtar, Safyan; Khan, Imad

    2018-03-01

    An efficient method is proposed to approximate sixth order boundary value problems. The proposed method is based on Legendre wavelet in which Legendre polynomial is used. The mechanism of the method is to use collocation points that converts the differential equation into a system of algebraic equations. For validation two test problems are discussed. The results obtained from proposed method are quite accurate, also close to exact solution, and other different methods. The proposed method is computationally more effective and leads to more accurate results as compared to other methods from literature.