Directory of Open Access Journals (Sweden)
Dan Ophir
2011-12-01
Full Text Available The process of making complex and controversial decisions, that is, dealing with moral or ethical dilemmas, have intrigued people and inspired writers from time immemorial. Dilemmas give both color and depth to characters in good literary works. But beyond literary fiction, dilemmas occupy society in every day issues such as in introducing legislation or solving current political problems. One example of a current political dilemma is how to deal with Iran’s quest for nuclear weapons. If it were possible to assess and quantify each of the alternative solutions for a given problem, the process of decision making would be much easier. If a problem involves only two optional solutions, game theory techniques can be used. However, real life problems are usually multi-unit, multi-optional problems, as in Iran
Bringing real-world problems into the classroom
Enserink, B.; De Haan, A.R.C.; Hermans, L.M.
2012-01-01
Real world problems are a challenge and a motivator for students to learn understanding and using the concepts of systems and actors. But using real world problems in the classroom is not without challenges and dilemmas. In the paper we explicitly address the issue of the need for quite intense supp
Problem Complexity Research from Energy Perspective
Feng, Pan; Jie, Qi
2013-01-01
Computational complexity is a particularly important objective. The idea of Landauer principle was extended through mapping three classic problems (sorting,ordered searching and max of N unordered numbers) into Maxwell demon thought experiment in this paper. The problems'complexity is defined on the entropy basis and the minimum energy required to solve them are rigorous deduced from the perspective of energy (entropy) and the second law of thermodynamics. Then the theoretical energy consumed by real program and basic operators of classical computer are both analyzed, the time complexity lower bounds of three problems'all possible algorithms are derived in this way. The lower bound is also deduced for the two n*n matrix multiplication problem. In the end, the reason why reversible computation is impossible and the possibility of super-linear energy consumption capacity which may be the power behind quantum computation are discussed, a conjecture is proposed which may prove NP!=P. The study will bring fresh an...
Problem Solving and Complex Systems
Guinand, Frédéric
2008-01-01
The observation and modeling of natural Complex Systems (CSs) like the human nervous system, the evolution or the weather, allows the definition of special abilities and models reusable to solve other problems. For instance, Genetic Algorithms or Ant Colony Optimizations are inspired from natural CSs to solve optimization problems. This paper proposes the use of ant-based systems to solve various problems with a non assessing approach. This means that solutions to some problem are not evaluated. They appear as resultant structures from the activity of the system. Problems are modeled with graphs and such structures are observed directly on these graphs. Problems of Multiple Sequences Alignment and Natural Language Processing are addressed with this approach.
Complex analogues of real problems
DEFF Research Database (Denmark)
Esdahl-Schou, Rune
This thesis will be a mix of different problems in number theory. As such it is split into two natural parts. The rst part focuses on normal numbers and construction of numbers that are normal to a given complex base. It is written in the style of a thorough and introductory paper on that subject...... and Tichy in [Madritsch et al., 2008] and [Madritsch, 2008] and contains a generalisation of the main theorem in [Madritsch, 2008]. The second part of the thesis focuses on Diophantine approximation, mainly on a famous conjecture by Schmidt from the 1980s. This conjecture was solved by Badziahin, Pollington...... and Velani, and inspired by this An gave a different proof which provides a stronger result. The conjecture is concerned with intersections of certain sets in the plane and are as such a real problem. We will consider a slightly different setup where the real plane is replaced by the complex plane. Using...
Solving complex problems a handbook
Schönwandt, Walter; Grunau, Jens; Utz, Jürgen; Voermanek, Katrin
2014-01-01
When you're planning something big, problems appear rather quickly. We hear of them on a daily basis. The bigger or more complex a task, the more we have to deal with complicated, multidisciplinary task formulations. In many cases it is architecture, including urban and spatial planning, but also politics and all types of organizational forms, irrespective of whether they are public authorities or private enterprises, which are expected to deliver functional solutions for such challenges. This is precisely where this book is helpful. It introduces a methodology for developing target-specific,
SCHOOL VIOLENCE: A COMPLEX PROBLEM
Directory of Open Access Journals (Sweden)
María del Rosario Ayala-Carrillo
2015-07-01
Full Text Available School violence is one type of violence that reflects the breakdown of current society. It is impossible to speak of school violence as an isolated phenomenon without establishing nexuses between public and private life, between collective and individual behaviors, between family and community aspects, without making reference to differences in gender and the life stories of those who are the aggressors or the victims, and without considering the patriarchal culture and interpersonal relationships. When all these factor are interrelated, they make the problem of violence a very complex one that requires us to know the different factors in order to understand it and deal with it.
Solving complex fisheries management problems
DEFF Research Database (Denmark)
Petter Johnsen, Jahn; Eliasen, Søren Qvist
2011-01-01
A crucial issue for the new EU common fisheries policy is how to solve the discard problem. Through a study of the institutional set up and the arrangements for solving the discard problem in Denmark, the Faroe Islands, Iceland and Norway, the article identifies the discard problem as related...
Common ground, complex problems and decision making
Beers, P.J.; Boshuizen, H.P.A.; Kirschner, P.A.; Gijselaers, W.H.
2006-01-01
Organisations increasingly have to deal with complex problems. They often use multidisciplinary teams to cope with such problems where different team members have different perspectives on the problem, different individual knowledge and skills, and different approaches on how to solve the problem. I
Linear and complex analysis problem
Nikolski, Nikolai
1994-01-01
The 2-volume-book is an updated, reorganized and considerably enlarged version of the previous edition of the Research Problem Book in Analysis (LNM 1043), a collection familiar to many analysts, that has sparked off much research. This new edition, created in a joint effort by a large team of analysts, is, like its predecessor, a collection of unsolved problems of modern analysis designed as informally written mini-articles, each containing not only a statement of a problem but also historical and metho- dological comments, motivation, conjectures and discussion of possible connections, of plausible approaches as well as a list of references. There are now 342 of these mini- articles, almost twice as many as in the previous edition, despite the fact that a good deal of them have been solved!
Linear and complex analysis problem
Nikolski, Nikolai
1994-01-01
The 2-volume book is an updated, reorganized and considerably enlarged version of the previous edition of the Research Problem Book in Analysis (LNM 1043), a collection familiar to many analysts, that has sparked off much research. This new edition, created in a joint effort by a large team of analysts, is, like its predecessor, a collection of unsolved problems of modern analysis designed as informally written mini-articles, each containing not only a statement of a problem but also historical and methodological comments, motivation, conjectures and discussion of possible connections, of plausible approaches as well as a list of references. There are now 342 of these mini- articles, almost twice as many as in the previous edition, despite the fact that a good deal of them have been solved!
Advice Complexity of the Online Search Problem
DEFF Research Database (Denmark)
Kudahl, Christian
The online search problem is a fundamental problem in finance. The numerous direct applications include searching for optimal prices for commodity trading and trading foreign currencies. In this paper, we analyze the advice complexity of this problem. In particular, we are interested in identifying...
Advice Complexity of the Online Search Problem
DEFF Research Database (Denmark)
Clemente, Jhoirene; Hromkovič, Juraj; Komm, Dennis
2016-01-01
The online search problem is a fundamental problem in finance. The numerous direct applications include searching for optimal prices for commodity trading and trading foreign currencies. In this paper, we analyze the advice complexity of this problem. In particular, we are interested in identifying...
The Process of Solving Complex Problems
Fischer, Andreas; Greiff, Samuel; Funke, Joachim
2012-01-01
This article is about Complex Problem Solving (CPS), its history in a variety of research domains (e.g., human problem solving, expertise, decision making, and intelligence), a formal definition and a process theory of CPS applicable to the interdisciplinary field. CPS is portrayed as (a) knowledge acquisition and (b) knowledge application…
Bringing Lean Six Sigma to the Supply Chain Classroom: A Problem-Based Learning Case
Miller, Keith E.; Hill, Craig; Miller, Antoinette R.
2016-01-01
The article describes a project that employs problem-based learning (PBL) to teach the Lean Six Sigma (LSS) methodology as part of an undergraduate or graduate business course. It is scalable to a variety of course delivery and schedule formats, and uses data sets that can create distinct problem-solving scenarios for up to 16 student teams. It…
The Complexity of Rooted Phylogeny Problems
Bodirsky, Manuel
2011-01-01
Several computational problems in phylogenetic reconstruction can be formulated as restrictions of the following general problem: given a formula in conjunctive normal form where the literals are rooted triples, is there a rooted binary tree that satisfies the formula? If the formulas do not contain disjunctions, the problem becomes the famous rooted triple consistency problem, which can be solved in polynomial time by an algorithm of Aho, Sagiv, Szymanski, and Ullman. If the clauses in the formulas are restricted to disjunctions of negated triples, Ng, Steel, and Wormald showed that the problem remains NP-complete. We systematically study the computational complexity of the problem for all such restrictions of the clauses in the input formula. For certain restricted disjunctions of triples we present an algorithm that has sub-quadratic running time and is asymptotically as fast as the fastest known algorithm for the rooted triple consistency problem. We also show that any restriction of the general rooted ph...
BRINGING CULTURAL CONTENT AND AUTHENTIC MATERIALS TO ENHANCE PROBLEM-BASED LEARNING IN EFL CLASSES
2012-01-01
In a class where elements and filters of Problem-Based Learning are used, students are engaged in language learning through organied and purposeful activities with authentic materials and collaborative learning models. Research has shown that this approach is effective in raising student’s motivation, enhancing their problem solving and critical thinking skills, and deepening their understanding of the subject contents. This paper aims to answer the questions of when and how authentic materia...
Wright, Adam; Sittig, Dean F; McGowan, Julie; Ash, Joan S; Weed, Lawrence L
2014-01-01
Larry Weed, MD is widely known as the father of the problem-oriented medical record and inventor of the now-ubiquitous SOAP (subjective/objective/assessment/plan) note, for developing an electronic health record system (Problem-Oriented Medical Information System, PROMIS), and for founding a company (since acquired), which developed problem-knowledge couplers. However, Dr Weed's vision for medicine goes far beyond software--over the course of his storied career, he has relentlessly sought to bring the scientific method to medical practice and, where necessary, to point out shortcomings in the system and advocate for change. In this oral history, Dr Weed describes, in his own words, the arcs of his long career and the work that remains to be done.
Directory of Open Access Journals (Sweden)
Olga V. Shipulina
2013-01-01
Full Text Available The study explores how students, who had completed the AP calculus course, mathematized the optimal navigation real-life problem simulated in the Second Life Virtual Environment. The particular research interest was to investigate whether/how students’ empirical activity in VE influences the way of their mathematizing.
Quantum complexity of graph and algebraic problems
Energy Technology Data Exchange (ETDEWEB)
Doern, Sebastian
2008-02-04
This thesis is organized as follows: In Chapter 2 we give some basic notations, definitions and facts from linear algebra, graph theory, group theory and quantum computation. In Chapter 3 we describe three important methods for the construction of quantum algorithms. We present the quantum search algorithm by Grover, the quantum amplitude amplification and the quantum walk search technique by Magniez et al. These three tools are the basis for the development of our new quantum algorithms for graph and algebra problems. In Chapter 4 we present two tools for proving quantum query lower bounds. We present the quantum adversary method by Ambainis and the polynomial method introduced by Beals et al. The quantum adversary tool is very useful to prove good lower bounds for many graph and algebra problems. The part of the thesis containing the original results is organized in two parts. In the first part we consider the graph problems. In Chapter 5 we give a short summary of known quantum graph algorithms. In Chapter 6 to 8 we study the complexity of our new algorithms for matching problems, graph traversal and independent set problems on quantum computers. In the second part of our thesis we present new quantum algorithms for algebraic problems. In Chapter 9 to 10 we consider group testing problems and prove quantum complexity bounds for important problems from linear algebra. (orig.)
Directory of Open Access Journals (Sweden)
Pavel Gol'din
Full Text Available Miocene baleen whales were highly diverse and included tens of genera. However, their taxonomy and phylogeny, as well as relationships with living whales, are still a subject of controversy. Here, "Mesocetus" argillarius, a poorly known specimen from Denmark, is redescribed with a focus on the cranial anatomy. It was found to represent not only a new genus, Tranatocetus gen. nov., but also a new family; Tranatocetidae. The whales of this family have the rostral bones either overriding or dividing the frontals; the rostral bones are contacting the parietals and nasals dividing the maxillae on the vertex; the occipital shield is dorsoventrally bent. The tympanic bulla is particularly characteristic of this family featuring a short, narrow anterior portion with a rounded or squared anterior end and a wider and higher posterior portion that is swollen in the posteroventral area. A phylogenetic analysis including 51 taxa supports a monophyletic group comprising most Neogene and modern whales, with Tranatocetidae being possibly closer related to Balaenopteridae (rorquals than to Cetotheriidae. Tranatocetidae exhibit a charahteristic bulla shape. In fact, all Neogene and modern mysticete families examined have a unique shape of the tympanic bulla that is diagnostic at family-level. Inclusion of problematic taxa like Tranatocetus argillarius in phylogenies brings new understanding of the distribution and diagnostic value of character traits. This underlines the need for re-examination of earlier described specimens in the light of the wealth of new information published in later years.
Gol'din, Pavel; Steeman, Mette Elstrup
2015-01-01
Miocene baleen whales were highly diverse and included tens of genera. However, their taxonomy and phylogeny, as well as relationships with living whales, are still a subject of controversy. Here, "Mesocetus" argillarius, a poorly known specimen from Denmark, is redescribed with a focus on the cranial anatomy. It was found to represent not only a new genus, Tranatocetus gen. nov., but also a new family; Tranatocetidae. The whales of this family have the rostral bones either overriding or dividing the frontals; the rostral bones are contacting the parietals and nasals dividing the maxillae on the vertex; the occipital shield is dorsoventrally bent. The tympanic bulla is particularly characteristic of this family featuring a short, narrow anterior portion with a rounded or squared anterior end and a wider and higher posterior portion that is swollen in the posteroventral area. A phylogenetic analysis including 51 taxa supports a monophyletic group comprising most Neogene and modern whales, with Tranatocetidae being possibly closer related to Balaenopteridae (rorquals) than to Cetotheriidae. Tranatocetidae exhibit a charahteristic bulla shape. In fact, all Neogene and modern mysticete families examined have a unique shape of the tympanic bulla that is diagnostic at family-level. Inclusion of problematic taxa like Tranatocetus argillarius in phylogenies brings new understanding of the distribution and diagnostic value of character traits. This underlines the need for re-examination of earlier described specimens in the light of the wealth of new information published in later years.
Problem based learning - 'Bringing everything together' - A strategy for Graduate Nurse Programs.
Vittrup, Ann-Charlotte; Davey, Anna
2010-03-01
This article discusses a case study that was initiated by a Graduate Nurse Coordinator of an acute care inpatient hospital in Australia. It outlines the conceptualisation and creative implementation of a structured group problem based learning activity which was a component of a Graduate Nurse Program. The learning activity was based on the beliefs that knowledge acquisition today is an active process and should focus on the learner developing strategies to obtain, review and manage information. The learning activity implemented in this case study was valuable as it recognised the benefits that can be gained for the Graduate Nurse by ensuring the context of their teaching and learning activities is grounded in practical experiences. The learning activity aimed to prepare Graduate Nurses to cope with the multiple challenges faced as they enter the nursing profession by enhancing their skills of inquiry, problem solving and reasoning. The evaluation of this case study found that the incorporation of structured group problem based learning did promote the achievement of these educational outcomes with Graduate Nurses displaying critical thinking, clinical judgment and knowledge acquisition skills. An unexpected benefit of this activity for Graduate Nurses was the enhancement of clinical practice behaviours, such as communication and interactive skills. This case study describes the positive outcomes not only for Graduates Nurses in the application of their learning but also the wider benefits which can be gained for the organisation, patient care standards and the health care team. It is anticipated that this article will be an inspiration to others who are interested in implementing innovative teaching strategies into Graduate Nurse Programs.
TO THE PROBLEM OF COMPLEX GRAIN HARVESTING
Directory of Open Access Journals (Sweden)
Rinas N. A.
2014-11-01
Full Text Available The ways and the methods of the solution of the problem of complex cleaning of grain crops were proved; the de-pendences of engine capacity of the Massey Ferguson tractors of 8200 series on the capacity of a thresher of the hook-on combine were received
Cooper, Andrew F; Farooq, Asif B
2015-12-01
The importance of the regional dimension of health diplomacy is only gaining slow and uneven recognition. This is in many ways surprising. As demonstrated in the work of Deacon on the 'globalization of social policy', global social policy has been animated and debated not only at the multilateral level but at the regional level as well. But at least in the diplomatic literature, the importance of this regional dynamic (with a focus on diverse sites and actors and the pursuit of democratic control) has been missed. The objective of this article is to explore whether health diplomacy is catching up to this larger debate re-shaping the conceptualization and practice of diplomacy more generally. In some ways, the results may be counter-productive in that this shift may encourage an increasingly fragmented process. Yet, it may also point to some breakthroughs, with diplomats, acting as 'go to' personnel on the front lines of operational activity, enabling actors to integrate with one another to produce effective governance. In doing so, the regional dimension is given greater recognition as a component of health diplomacy, albeit in an uneven and sometimes awkward manner. Whereas global diplomacy generally emphasizes problem solving, the regional dimension is animated by a normative orientation.
Complexity of some problems concerning L systems
DEFF Research Database (Denmark)
Jones, Neil D.; Skyum, Sven
1979-01-01
We determine the computational complexity of membership, emptiness and infiniteness for several types ofL systems. TheL systems we consider are ED0L, E0L, EDT0L, and ET0L, with and without empty productions. For each problem and each type of system we establish both upper and lower bounds...... on the time or memory required for solution by Turing machines....
Dependability problems of complex information systems
Zamojski, Wojciech
2014-01-01
This monograph presents original research results on selected problems of dependability in contemporary Complex Information Systems (CIS). The ten chapters are concentrated around the following three aspects: methods for modelling of the system and its components, tasks ? or in more generic and more adequate interpretation, functionalities ? accomplished by the system and conditions for their correct realization in the dynamic operational environment. While the main focus is on theoretical advances and roadmaps for implementations of new technologies, a?much needed forum for sharing of the bes
Sensitive periods in epigenetics: bringing us closer to complex behavioral phenotypes.
Nagy, Corina; Turecki, Gustavo
2012-08-01
Genetic studies have attempted to elucidate causal mechanisms for the development of complex disease, but genome-wide associations have been largely unsuccessful in establishing these links. As an alternative link between genes and disease, recent efforts have focused on mechanisms that alter the function of genes without altering the underlying DNA sequence. Known as epigenetic mechanisms, these include DNA methylation, chromatin conformational changes through histone modifications, ncRNAs and, most recently, 5-hydroxymethylcytosine. Although DNA methylation is involved in normal development, aging and gene regulation, altered methylation patterns have been associated with disease. It is generally believed that early life constitutes a period during which there is increased sensitivity to the regulatory effects of epigenetic mechanisms. The purpose of this review is to outline the contribution of epigenetic mechanisms to genomic function, particularly in the development of complex behavioral phenotypes, focusing on the sensitive periods.
Estimating uncertainties in complex joint inverse problems
Afonso, Juan Carlos
2016-04-01
Sources of uncertainty affecting geophysical inversions can be classified either as reflective (i.e. the practitioner is aware of her/his ignorance) or non-reflective (i.e. the practitioner does not know that she/he does not know!). Although we should be always conscious of the latter, the former are the ones that, in principle, can be estimated either empirically (by making measurements or collecting data) or subjectively (based on the experience of the researchers). For complex parameter estimation problems in geophysics, subjective estimation of uncertainty is the most common type. In this context, probabilistic (aka Bayesian) methods are commonly claimed to offer a natural and realistic platform from which to estimate model uncertainties. This is because in the Bayesian approach, errors (whatever their nature) can be naturally included as part of the global statistical model, the solution of which represents the actual solution to the inverse problem. However, although we agree that probabilistic inversion methods are the most powerful tool for uncertainty estimation, the common claim that they produce "realistic" or "representative" uncertainties is not always justified. Typically, ALL UNCERTAINTY ESTIMATES ARE MODEL DEPENDENT, and therefore, besides a thorough characterization of experimental uncertainties, particular care must be paid to the uncertainty arising from model errors and input uncertainties. We recall here two quotes by G. Box and M. Gunzburger, respectively, of special significance for inversion practitioners and for this session: "…all models are wrong, but some are useful" and "computational results are believed by no one, except the person who wrote the code". In this presentation I will discuss and present examples of some problems associated with the estimation and quantification of uncertainties in complex multi-observable probabilistic inversions, and how to address them. Although the emphasis will be on sources of uncertainty related
Team-Based Complex Problem Solving: A Collective Cognition Perspective
Hung, Woei
2013-01-01
Today, much problem solving is performed by teams, rather than individuals. The complexity of these problems has exceeded the cognitive capacity of any individual and requires a team of members to solve them. The success of solving these complex problems not only relies on individual team members who possess different but complementary expertise,…
Complexity of valued constraint satisfaction problems
Živný, Stanislav
2012-01-01
The topic of this book is the following optimisation problem: given a set of discrete variables and a set of functions, each depending on a subset of the variables, minimise the sum of the functions over all variables. This fundamental research problem has been studied within several different contexts of discrete mathematics, computer science and artificial intelligence under different names: Min-Sum problems, MAP inference in Markov random fields (MRFs) and conditional random fields (CRFs), Gibbs energy minimisation, valued constraint satisfaction problems (VCSPs), and, for two-state variabl
Zhang, Songchuan; Xia, Youshen
2016-12-28
Much research has been devoted to complex-variable optimization problems due to their engineering applications. However, the complex-valued optimization method for solving complex-variable optimization problems is still an active research area. This paper proposes two efficient complex-valued optimization methods for solving constrained nonlinear optimization problems of real functions in complex variables, respectively. One solves the complex-valued nonlinear programming problem with linear equality constraints. Another solves the complex-valued nonlinear programming problem with both linear equality constraints and an ℓ₁-norm constraint. Theoretically, we prove the global convergence of the proposed two complex-valued optimization algorithms under mild conditions. The proposed two algorithms can solve the complex-valued optimization problem completely in the complex domain and significantly extend existing complex-valued optimization algorithms. Numerical results further show that the proposed two algorithms have a faster speed than several conventional real-valued optimization algorithms.
Solving the Inverse-Square Problem with Complex Variables
Gauthier, N.
2005-01-01
The equation of motion for a mass that moves under the influence of a central, inverse-square force is formulated and solved as a problem in complex variables. To find the solution, the constancy of angular momentum is first established using complex variables. Next, the complex position coordinate and complex velocity of the particle are assumed…
On Complexity of Isoperimetric Problems on Trees
Daneshgar, Amir
2010-01-01
This paper is aimed to investigate some computational aspects of different isoperimetric problems on weighted trees. In this regard, we consider different connectivity parameters called {\\it minimum normalized cuts}/{\\it isoperimteric numbers} defined through taking minimum of the maximum or the mean of the normalized outgoing flows from a set of subdomains of vertices, where these subdomains constitute a {\\it partition}/{\\it subpartition}. Following the main result of [A. Daneshgar, {\\it et. al.}, {\\it On the isoperimetric spectrum of graphs and its approximations}, JCTB, (2010)], it is known that the isoperimetric number and the minimum normalized cut both can be described as $\\{0,1\\}$-optimization programs, where the latter one does {\\it not} admit a relaxation to the reals. We show that the decision problem for the case of taking $k$-partitions and the maximum (called the max normalized cut problem {\\rm NCP}$^M$) as well as the other two decision problems for the mean version (referred to as {\\rm IPP}$^m$...
On the Complexity of Container Stowage Planning Problems
DEFF Research Database (Denmark)
Pacino, Dario; Tierney, Kevin; Jensen, Rune Møller
The optimization of container ship and depot operations embeds the k-shift problem, in which containers must be stowed with at most k rehandles. We first solve an open problem showing that changing from uncapacitated to capacitated stacks reduces the problem complexity from NP-complete to polynom......The optimization of container ship and depot operations embeds the k-shift problem, in which containers must be stowed with at most k rehandles. We first solve an open problem showing that changing from uncapacitated to capacitated stacks reduces the problem complexity from NP......-complete to polynomial. We then examine the complexity of an abstraction of the current state-of-the-art container ship stowage planning, the hatch overstow problem. We show that this problem is NP-complete, which means that even abstract formulation of container ship stowage planning is intractable....
Automatic Algorithm Selection for Complex Simulation Problems
Ewald, Roland
2012-01-01
To select the most suitable simulation algorithm for a given task is often difficult. This is due to intricate interactions between model features, implementation details, and runtime environment, which may strongly affect the overall performance. An automated selection of simulation algorithms supports users in setting up simulation experiments without demanding expert knowledge on simulation. Roland Ewald analyzes and discusses existing approaches to solve the algorithm selection problem in the context of simulation. He introduces a framework for automatic simulation algorithm selection and
Preparing for Complexity and Wicked Problems through Transformational Learning Approaches
Yukawa, Joyce
2015-01-01
As the information environment becomes increasingly complex and challenging, Library and Information Studies (LIS) education is called upon to nurture innovative leaders capable of managing complex situations and "wicked problems." While disciplinary expertise remains essential, higher levels of mental complexity and adaptive…
Deterministic Computational Complexity of the Quantum Separability Problem
Ioannou, L M
2006-01-01
Ever since entanglement was identified as a computational and cryptographic resource, effort has been made to find an efficient way to tell whether a given density matrix represents an unentangled, or separable, state. Essentially, this is the quantum separability problem. In Section 1, I begin with a brief introduction to bipartite separability and entanglement, and a basic formal definition of the quantum separability problem. I conclude with a summary of one-sided tests for separability, including those involving semidefinite programming. In Section 2, I treat the separability problem as a computational decision problem and motivate its approximate formulations. After a review of basic complexity-theoretic notions, I discuss the computational complexity of the separability problem (including a Turing-NP-complete formulation of the problem and a proof of "strong NP-hardness" (based on a new NP-hardness proof by Gurvits)). In Section 3, I give a comprehensive survey and complexity analysis of deterministic a...
Modeling Complex Chemical Systems: Problems and Solutions
van Dijk, Jan
2016-09-01
Non-equilibrium plasmas in complex gas mixtures are at the heart of numerous contemporary technologies. They typically contain dozens to hundreds of species, involved in hundreds to thousands of reactions. Chemists and physicists have always been interested in what are now called chemical reduction techniques (CRT's). The idea of such CRT's is that they reduce the number of species that need to be considered explicitly without compromising the validity of the model. This is usually achieved on the basis of an analysis of the reaction time scales of the system under study, which identifies species that are in partial equilibrium after a given time span. The first such CRT that has been widely used in plasma physics was developed in the 1960's and resulted in the concept of effective ionization and recombination rates. It was later generalized to systems in which multiple levels are effected by transport. In recent years there has been a renewed interest in tools for chemical reduction and reaction pathway analysis. An example of the latter is the PumpKin tool. Another trend is that techniques that have previously been developed in other fields of science are adapted as to be able to handle the plasma state of matter. Examples are the Intrinsic Low Dimension Manifold (ILDM) method and its derivatives, which originate from combustion engineering, and the general-purpose Principle Component Analysis (PCA) technique. In this contribution we will provide an overview of the most common reduction techniques, then critically assess the pros and cons of the methods that have gained most popularity in recent years. Examples will be provided for plasmas in argon and carbon dioxide.
Solving Complex Problems to Create Charter Extension Options
DEFF Research Database (Denmark)
Tippmann, Esther; Nell, Phillip Christopher
This study examines subsidiary-driven problem solving processes and their potential to create advanced solutions for charter extension options. Problem solving theory suggests that biases in problem formulation and solution search can confine problem solving potential. We thus argue that balanced...... undertaken by 29 subsidiary units supports our hypotheses, demonstrating that these activities are a means to systematically reduce inherent problem solving biases. This study contributes to problem solving theory, the literature on headquarters’ roles in complex organizations, as well as the literature...... solution search, or activities to reconcile the need for some solution features to be locally-tailored while others can be internationally standardized, mediates the relationships between problem complexity/headquarters involvement and the capacity to create advanced solutions. An analysis of 67 projects...
Solomon, Olga; Heritage, John; Yin, Larry; Maynard, Douglas W.; Bauman, Margaret L.
2016-01-01
Conversation and discourse analyses were used to examine medical problem presentation in pediatric care. Healthcare visits involving children with ASD and typically developing children were analyzed. We examined how children's communicative and epistemic capabilities, and their opportunities to be socialized into a competent patient role are…
Newtonian Nonlinear Dynamics for Complex Linear and Optimization Problems
Vázquez, Luis
2013-01-01
Newtonian Nonlinear Dynamics for Complex Linear and Optimization Problems explores how Newton's equation for the motion of one particle in classical mechanics combined with finite difference methods allows creation of a mechanical scenario to solve basic problems in linear algebra and programming. The authors present a novel, unified numerical and mechanical approach and an important analysis method of optimization. This book also: Presents mechanical method for determining matrix singularity or non-independence of dimension and complexity Illustrates novel mathematical applications of classical Newton’s law Offers a new approach and insight to basic, standard problems Includes numerous examples and applications Newtonian Nonlinear Dynamics for Complex Linear and Optimization Problems is an ideal book for undergraduate and graduate students as well as researchers interested in linear problems and optimization, and nonlinear dynamics.
Energy Technology Data Exchange (ETDEWEB)
Glantz, C.S.; Estes, J.C.; Andrews, G.L.
1993-07-01
Current research and emerging standards in teaching and learning say that students learning best when information is presented in a meaningful context and when the students are involved in things they care about. At the US Department of Energy`s (DOE) Pacific Northwest Laboratory (PNL), science education programs have been developed that incorporate these concepts. To help students and teachers understand the process of ``doing`` science, we provide immersion-based programs in such technical areas as meteorology, marine sciences, wetland ecology, groundwater hydrology, robotics, lasers materials science, biology, and archaeology. This paper focuses on a meteorology program the authors developed in recent years to support this immersion experience approach. We will discuss how we link meteorology with other subject matter, how we show the relevance of meteorology to real-world problems, and how we immerse student`s and teachers in activities that help them understand how scientists uncover knowledge and solve problems.
On the complexity of container stowage planning problems
DEFF Research Database (Denmark)
Tierney, Kevin; Pacino, Dario; Jensen, Rune Møller
2014-01-01
The optimization of container ship and depot operations embeds the kk-shift problem, in which containers must be stowed in stacks such that at most kk containers must be removed in order to reach containers below them. We first solve an open problem introduced by Avriel et al. (2000) by showing...... that changing from uncapacitated to capacitated stacks reduces the complexity of this problem from NP-complete to polynomial. We then examine the complexity of the current state-of-the-art abstraction of container ship stowage planning, wherein containers and slots are grouped together. To do this, we define...... the hatch overstow problem, in which a set of containers are placed on top of the hatches of a container ship such that the number of containers that are stowed on hatches that must be accessed is minimized. We show that this problem is NP-complete by a reduction from the set-covering problem, which means...
Structuring and assessing large and complex decision problems using MCDA
DEFF Research Database (Denmark)
Barfod, Michael Bruhn
This paper presents an approach for the structuring and assessing of large and complex decision problems using multi-criteria decision analysis (MCDA). The MCDA problem is structured in a decision tree and assessed using the REMBRANDT technique featuring a procedure for limiting the number of pair...
Knowledge based method for solving complexity in design problems
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 kno
Kirschke, Sabrina; Newig, Jens; Völker, Jeanette; Borchardt, Dietrich
2017-03-08
Problem complexity is often assumed to hamper effective environmental policy delivery. However, this claim is hardly substantiated, given the dominance of qualitative small-n designs in environmental governance research. We studied 37 types of contemporary problems defined by German water governance to assess the impact of problem complexity on policy delivery through public authorities. The analysis is based on a unique data set related to these problems, encompassing both in-depth interview-based data on complexities and independent official data on policy delivery. Our findings show that complexity in fact tends to delay implementation at the stage of planning. However, different dimensions of complexity (goals, variables, dynamics, interconnections, and uncertainty) impact on the different stages of policy delivery (goal formulation, stages and degrees of implementation) in various ways.
Enhanced Bee Colony Algorithm for Complex Optimization Problems
Directory of Open Access Journals (Sweden)
S.Suriya
2012-01-01
Full Text Available Optimization problems are considered to be one kind of NP hard problems. Usually heuristic approaches are found to provide solutions for NP hard problems. There are a plenty of heuristic algorithmsavailable to solve optimization problems namely: Ant Colony Optimization, Particle Swarm Optimization, Bee Colony Optimization, etc. The basic Bee Colony algorithm, a population based search algorithm, is analyzed to be a novel tool for complex optimization problems. The algorithm mimics the food foraging behavior of swarmsof honey bees. This paper deals with a modified fitness function of Bee Colony algorithm. The effect of problem dimensionality on the performance of the algorithms will be investigated. This enhanced Bee Colony Optimization will be evaluated based on the well-known benchmark problems. The testing functions like Rastrigin, Rosenbrock, Ackley, Griewank and Sphere are used to evaluavate the performance of the enhanced Bee Colony algorithm. The simulation will be developed on MATLAB.
New complex variable meshless method for advection-diffusion problems
Institute of Scientific and Technical Information of China (English)
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 investigate 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.
From problem solving to problem definition: scrutinizing the complex nature of clinical practice.
Cristancho, Sayra; Lingard, Lorelei; Regehr, Glenn
2017-02-01
In medical education, we have tended to present problems as being singular, stable, and solvable. Problem solving has, therefore, drawn much of medical education researchers' attention. This focus has been important but it is limited in terms of preparing clinicians to deal with the complexity of the 21st century healthcare system in which they will provide team-based care for patients with complex medical illness. In this paper, we use the Soft Systems Engineering principles to introduce the idea that in complex, team-based situations, problems usually involve divergent views and evolve with multiple solution iterations. As such we need to shift the conversation from (1) problem solving to problem definition, and (2) from a problem definition derived exclusively at the level of the individual to a definition derived at the level of the situation in which the problem is manifested. Embracing such a focus on problem definition will enable us to advocate for novel educational practices that will equip trainees to effectively manage the problems they will encounter in complex, team-based healthcare.
Complex saddle points and the sign problem in complex Langevin simulation
Hayata, Tomoya; Tanizaki, Yuya
2015-01-01
We show that complex Langevin simulation converges to a wrong result, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Semantic Annotation of Complex Text Structures in Problem Reports
Malin, Jane T.; Throop, David R.; Fleming, Land D.
2011-01-01
Text analysis is important for effective information retrieval from databases where the critical information is embedded in text fields. Aerospace safety depends on effective retrieval of relevant and related problem reports for the purpose of trend analysis. The complex text syntax in problem descriptions has limited statistical text mining of problem reports. The presentation describes an intelligent tagging approach that applies syntactic and then semantic analysis to overcome this problem. The tags identify types of problems and equipment that are embedded in the text descriptions. The power of these tags is illustrated in a faceted searching and browsing interface for problem report trending that combines automatically generated tags with database code fields and temporal information.
On the computational complexity of sequence design problems
Energy Technology Data Exchange (ETDEWEB)
Hart, W.E. [Sandia National Labs., Albuquerque, NM (United States). Algorithms and Discrete Mathematics Dept.
1996-12-31
Inverse protein folding concerns the identification of an amino acid sequence that folds to a given structure. Sequence design problems attempt to avoid the apparent difficulty of inverse protein folding by defining an energy that can be minimized to find protein-like sequences. The authors evaluate the practical relevance of two sequence design problems by analyzing their computation complexity. They show that the canonical method of sequence design is intractable, and describe approximation algorithms for this problem. The authors also describe an efficient algorithm that exactly solves the grand canonical method. The analysis shows how sequence design problems can fail to reduce the difficulty of the inverse protein folding problem, and highlights the need to analyze these problems to evaluate their practical relevance.
A complex variable meshless method for fracture problems
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Based on the moving least-square (MLS) approximation, the complex variable moving least-square approximation (CVMLS) is discussed in this paper. The complex variable moving least-square approximation cannot form ill-conditioned equations, and has greater precision and computational efficiency. Using the analytical solution near the tip of a crack, the trial functions in the complex variable moving least-square approxi- mation are extended, and the corresponding approximation function is obtained. And from the minimum potential energy principle, a complex variable meshless method for fracture problems is presented, and the formulae of the complex variable meshless method are obtained. The complex variable meshless method in this paper has greater precision and computational efficiency than the conventional meshless method. Some examples are given.
Information-related complexity: a problem-oriented approach
Perevalov, Eugene
2013-01-01
A general notion of information-related complexity applicable to both natural and man-made systems is proposed. The overall approach is to explicitly consider a rational agent performing a certain task with a quantifiable degree of success. The complexity is defined as the minimum (quasi-)quantity of information that's necessary to complete the task to the given extent -- measured by the corresponding loss. The complexity so defined is shown to generalize the existing notion of statistical complexity when the system in question can be described by a discrete-time stochastic process. The proposed definition also applies, in particular, to optimization and decision making problems under uncertainty in which case it gives the agent a useful measure of the problem's "susceptibility" to additional information and allows for an estimation of the potential value of the latter.
Extended variational theory of complex rays in heterogeneous Helmholtz problem
Li, Hao; Ladeveze, Pierre; Riou, Hervé
2017-02-01
In the past years, a numerical technique method called Variational Theory of Complex Rays (VTCR) has been developed for vibration problems in medium frequency. It is a Trefftz Discontinuous Galerkin method which uses plane wave functions as shape functions. However this method is only well developed in homogeneous case. In this paper, VTCR is extended to the heterogeneous Helmholtz problem by creating a new base of shape functions. Numerical examples give a scope of the performances of such an extension of VTCR.
EEG activity during the performance of complex mental problems.
Jausovec, N; Jausovec, K
2000-04-01
This study investigated differences in cognitive processes related to problem complexity. It was assumed that these differences would be reflected in respondents' EEG activity--spectral power and coherence. A second issue of the study was to compare differences between the lower (alpha(1) = 7.9-10.0 Hz), and upper alpha band (alpha(2) = 10.1-12.9 Hz). In the first experiment two well-defined problems with two levels of complexity were used. Only minor differences in EEG power and coherence measures related to problem complexity were observed. In the second experiment divergent production problems resembling tasks on creativity tests were compared with dialectic problems calling for creative solutions. Differences in EEG power measures were mainly related to the form of problem presentation (figural/verbal). In contrast, coherence was related to the level of creativity needed to solve a problem. Noticeable increased intra- and interhemispheric cooperation between mainly the far distant brain regions was observed in the EEG activity of respondents while solving the dialectic problems. These results are explained by the more intense involvement of the long cortico-cortical fiber system in creative thinking. Differences between the lower and upper alpha band were significant for the power and coherence measures. In Experiment 2, fewer differences were observed in power measures in the upper alpha band than in the lower alpha band. A reverse pattern was observed for the coherence measures. These results hint to a functional independence of the two alpha bands, however, they do not allow to draw firm conclusions about their functional meanings. The study showed that it is unlikely that individuals solve well- and ill-defined problems by employing similar cognitive strategies.
Approximation algorithms for indefinite complex quadratic maximization problems
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
In this paper,we consider the following indefinite complex quadratic maximization problem: maximize zHQz,subject to zk ∈ C and zkm = 1,k = 1,...,n,where Q is a Hermitian matrix with trQ = 0,z ∈ Cn is the decision vector,and m 3.An (1/log n) approximation algorithm is presented for such problem.Furthermore,we consider the above problem where the objective matrix Q is in bilinear form,in which case a 0.7118 cos mπ 2approximation algorithm can be constructed.In the context of quadratic optimization,various extensions and connections of the model are discussed.
Polynomial complexity algorithm for Max-Cut problem
Katkov, Mikhail
2010-01-01
The standard NP-complete max-cut problem is reformulated as a binary quadratic program xQx s.t x^2=1. This problem is further reformulated as global minimum of quartic polynomial (xQ'x - z)^2 + \\sum_i (x_i^2-1)^2+ \\alpha z^2, for some \\alpha. The global minimum is found by polynomial complexity semi-definite program. Numerical examples and code is provided. The resulting algorithm solves arbitrary max-cut problem in polynomial time, therefore P=NP.
Complexity and Approximation of the Continuous Network Design Problem
Gairing, Martin; Harks, Tobias; Klimm, Max
2014-01-01
We revisit a classical problem in transportation, known as the continuous (bilevel) network design problem, CNDP for short. We are given a graph for which the latency of each edge depends on the ratio of the edge flow and the capacity installed. The goal is to find an optimal investment in edge capacities so as to minimize the sum of the routing cost of the induced Wardrop equilibrium and the investment cost. While this problem is considered as challenging in the literature, its complexity st...
Modal and Mixed Specifications: Key Decision Problems and their Complexities
DEFF Research Database (Denmark)
Antonik, Adam; Huth, Michael; Larsen, Kim Guldstrand;
2010-01-01
Modal and mixed transition systems are specification formalisms that allow mixing of over- and under-approximation. We discuss three fundamental decision problems for such specifications: whether a set of specifications has a common implementation, whether a sole specification has an implementation......, and whether all implementations of one specification are implementations of another one. For each of these decision problems we investigate the worst-case computational complexity for the modal and mixed case. We show that the first decision problem is EXPTIME-complete for modal as well as for mixed...... specifications. We prove that the second decision problem is EXPTIME-complete for mixed specifications (while it is known to be trivial for modal ones). The third decision problem is furthermore demonstrated to be EXPTIME-complete for mixed specifications....
Investigating the Effect of Complexity Factors in Gas Law Problems
Schuttlefield, Jennifer D.; Kirk, John; Pienta, Norbert J.; Tang, Hui
2012-01-01
Undergraduate students were asked to complete gas law questions using a Web-based tool as a first step in our understanding of the role of cognitive load in chemistry word questions and in helping us assess student problem-solving. Each question contained five different complexity factors, which were randomly assigned by the tool so that a…
The Computational Complexity of the Parallel Knock-Out Problem
Broersma, H.J.; Johnson, M.; Paulusma, D.; Stewart, I.A.; Correa, J.R.; Hevia, A.; Kiwi, M.
2006-01-01
We consider computational complexity questions related to parallel knock-out schemes for graphs. In such schemes, in each round, each remaining vertex of a given graph eliminates exactly one of its neighbours. We show that the problem of whether, for a given graph, such a scheme can be found that el
What Do Employers Pay for Employees' Complex Problem Solving Skills?
Ederer, Peer; Nedelkoska, Ljubica; Patt, Alexander; Castellazzi, Silvia
2015-01-01
We estimate the market value that employers assign to the complex problem solving (CPS) skills of their employees, using individual-level Mincer-style wage regressions. For the purpose of the study, we collected new and unique data using psychometric measures of CPS and an extensive background questionnaire on employees' personal and work history.…
The Complex Route to Success: Complex Problem-Solving Skills in the Prediction of University Success
Stadler, Matthias J.; Becker, Nicolas; Greiff, Samuel; Spinath, Frank M.
2016-01-01
Successful completion of a university degree is a complex matter. Based on considerations regarding the demands of acquiring a university degree, the aim of this paper was to investigate the utility of complex problem-solving (CPS) skills in the prediction of objective and subjective university success (SUS). The key finding of this study was that…
Radio interferometric gain calibration as a complex optimization problem
Smirnov, Oleg
2015-01-01
Recent developments in optimization theory have extended some traditional algorithms for least-squares optimization of real-valued functions (Gauss-Newton, Levenberg-Marquardt, etc.) into the domain of complex functions of a complex variable. This employs a formalism called the Wirtinger derivative, and derives a full-complex Jacobian counterpart to the conventional real Jacobian. We apply these developments to the problem of radio interferometric gain calibration, and show how the general complex Jacobian formalism, when combined with conventional optimization approaches, yields a whole new family of calibration algorithms, including those for the polarized and direction-dependent gain regime. We further extend the Wirtinger calculus to an operator-based matrix calculus for describing the polarized calibration regime. Using approximate matrix inversion results in computationally efficient implementations; we show that some recently proposed calibration algorithms such as StefCal and peeling can be understood...
How Humans Solve Complex Problems: The Case of the Knapsack Problem
Murawski, Carsten; Bossaerts, Peter
2016-01-01
Life presents us with problems of varying complexity. Yet, complexity is not accounted for in theories of human decision-making. Here we study instances of the knapsack problem, a discrete optimisation problem commonly encountered at all levels of cognition, from attention gating to intellectual discovery. Complexity of this problem is well understood from the perspective of a mechanical device like a computer. We show experimentally that human performance too decreased with complexity as defined in computer science. Defying traditional economic principles, participants spent effort way beyond the point where marginal gain was positive, and economic performance increased with instance difficulty. Human attempts at solving the instances exhibited commonalities with algorithms developed for computers, although biological resource constraints–limited working and episodic memories–had noticeable impact. Consistent with the very nature of the knapsack problem, only a minority of participants found the solution–often quickly–but the ones who did appeared not to realise. Substantial heterogeneity emerged, suggesting why prizes and patents, schemes that incentivise intellectual discovery but discourage information sharing, have been found to be less effective than mechanisms that reveal private information, such as markets. PMID:27713516
On the Complexity of Rearrangement Problems under the Breakpoint Distance
Kovac, Jakub
2011-01-01
Tannier et al. introduced a generalization of breakpoint distance for multichromosomal genomes. They showed that the median problem under the breakpoint distance is solvable in polynomial time in the multichromosomal circular and mixed models. This is intriguing, since in all other rearrangement models (DCJ, reversal, unichromosomal or multilinear breakpoint models), the problem is NP-hard. The complexity of the small or even the large phylogeny problem under the breakpoint distance remained an open problem. We improve the algorithm for the median problem and show that it is equivalent to the problem of finding maximum cardinality non-bipartite matching (under linear reduction). On the other hand, we prove that the more general small phylogeny problem is NP-hard. Surprisingly, we show that it is already NP-hard (or even APX-hard) for 4 species (a quartet phylogeny). In other words, while finding an ancestor for 3 species is easy, already finding two ancestors for 4 species is hard. We also show that, in the u...
Data Mining and Complex Problems: Case Study in Composite Materials
Rabelo, Luis; Marin, Mario
2009-01-01
Data mining is defined as the discovery of useful, possibly unexpected, patterns and relationships in data using statistical and non-statistical techniques in order to develop schemes for decision and policy making. Data mining can be used to discover the sources and causes of problems in complex systems. In addition, data mining can support simulation strategies by finding the different constants and parameters to be used in the development of simulation models. This paper introduces a framework for data mining and its application to complex problems. To further explain some of the concepts outlined in this paper, the potential application to the NASA Shuttle Reinforced Carbon-Carbon structures and genetic programming is used as an illustration.
Complex variable element-free Galerkin method for viscoelasticity problems
Institute of Scientific and Technical Information of China (English)
Cheng Yu-Min; Li Rong-Xin; Peng Miao-Juan
2012-01-01
Based on the complex variable moving least-square (CVMLS) approximation,the complex variable element-free Galerkin (CVEFG) method for two-dimensional viscoelasticity problems under the creep condition is presented in this paper.The Galerkin weak form is employed to obtain the equation system,and the penalty method is used to apply the essential boundary conditions,then the corresponding formulae of the CVEFG method for two-dimensional viscoelasticity problems under the creep condition are obtained. Compared with the element-free Galerkin (EFG) method,with the same node distribution,the CVEFG method has higher precision,and to obtain the similar precision,the CVEFG method has greater computational efficiency. Some numerical examples are given to demonstrate the validity and the efficiency of the method.
Complex saddle points and the sign problem in complex Langevin simulation
Hayata, Tomoya; Hidaka, Yoshimasa; Tanizaki, Yuya
2016-10-01
We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Complex saddle points and the sign problem in complex Langevin simulation
Directory of Open Access Journals (Sweden)
Tomoya Hayata
2016-10-01
Full Text Available We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Approximation Complexity of Complex-Weighted Degree-Two Counting Constraint Satisfaction Problems
Yamakami, Tomoyuki
2011-01-01
Constraint satisfaction problems have been studied in numerous fields with practical and theoretical interests. In recent years, major breakthroughs have been made in a study of counting constraint satisfaction problems (or #CSPs). In particular, a computational complexity classification of bounded-degree #CSPs has been discovered for all degrees except for two, where the "degree" of an input instance is the maximal number of times that each input variable appears in a given set of constraints. Despite the efforts of recent studies, however, a complexity classification of degree-2 #CSPs has eluded from our understandings. This paper challenges this open problem and gives its partial solution by applying two novel proof techniques--T_{2}-constructibility and parametrized symmetrization--which are specifically designed to handle "arbitrary" constraints under randomized approximation-preserving reductions. We partition entire constraints into four sets and we classify the approximation complexity of all degree-2...
Parameterized Complexity of the k-anonymity Problem
Bonizzoni, Paola; Dondi, Riccardo; Pirola, Yuri
2009-01-01
The problem of publishing personal data without giving up privacy is becoming increasingly important. An interesting formalization that has been recently proposed is the $k$-anonymity. This approach requires that the rows of a table are partitioned in clusters of size at least $k$ and that all the rows in a cluster become the same tuple, after the suppression of some entries. The natural optimization problem, where the goal is to minimize the number of suppressed entries, is known to be APX-hard even when the records values are over a binary alphabet and $k=3$, and when the records have length at most 8 and $k=4$ . In this paper we study how the complexity of the problem is influenced by different parameters. In this paper we follow this direction of research, first showing that the problem is W[1]-hard when parameterized by the size of the solution (and the value $k$). Then we exhibit a fixed parameter algorithm, when the problem is parameterized by the size of the alphabet and the number of columns. Finally...
The Similar Structures and Control Problems of Complex Systems
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between the functions and behaviors of these systems and their similar structures will be studied. Owing to the management of social systems and the course of evolution of biotic systems may be regarded as control processes, the researches will be within the scope of control problems. Moreover, since it is difficult to model for biotic and social systems, it will start with the control problems of complex systems, possessing similar structures, in engineering.The obtained results show that for either linear or nonlinear systems and for a lot of control problemssimilar structures lead to a series of simplifications. In general, the original system may be decomposed into reduced amount of subsystems with lower dimensions and simpler structures. By virtue of such subsystems, the control problems of original system can be solved more simply.At last, it turns round to observe the biotic and social systems and some analyses are given.
Complexity indices for the travelling salesman problem and data mining
Directory of Open Access Journals (Sweden)
Dragos Cvetković
2012-03-01
Full Text Available In this survey paper we extend our previous work on complexity indices for the travelling salesman problem (TSP, summarized in cite{CvCK3}, using graph spectral techniques of data mining. A complexity index is an invariant of an instance $I$ by which we can predict the execution time of an exact algorithm for TSP for $I$. We consider the symmetric travelling salesman problem with instances $I$ represented by complete graphs $G$ with distances between vertices (cities as edge weights (lengths. Intuitively, the hardness of an instance $G$ depends on the distribution of short edges within $G$. Therefore we consider some short edge subgraphs of $G$ (minimal spanning tree, critical connected subgraph, and several others as non-weighted graphs and several their invariants as potential complexity indices. Here spectral invariants (e.g. spectral radius of the adjacency matrix play an important role since, in general, there are intimate relations between eigenvalues and the structure of a graph. Since hidden details of short edge subgraphs really determine the hardness of the instance, we use techniques of data mining to find them. In particular, spectral clustering algorithms are used including information obtained from the spectral gap in Laplacian spectra of short edge subgraphs.
Semilinear mixed problems on Hilbert complexes and their numerical approximation
Holst, Michael
2010-01-01
Arnold, Falk, and Winther recently showed [Bull. Amer. Math. Soc. 47 (2010), 281-354] that linear, mixed variational problems, and their numerical approximation by mixed finite element methods, can be studied using the powerful, abstract language of Hilbert complexes. In another recent article [arXiv:1005.4455], we extended the Arnold-Falk-Winther framework by analyzing variational crimes (a la Strang) on Hilbert complexes. In particular, this gave a treatment of finite element exterior calculus on manifolds, generalizing techniques from surface finite element methods and recovering earlier a priori estimates for the Laplace-Beltrami operator on 2- and 3-surfaces, due to Dziuk [Lecture Notes in Math., vol. 1357 (1988), 142-155] and later Demlow [SIAM J. Numer. Anal., 47 (2009), 805-827], as special cases. In the present article, we extend the Hilbert complex framework in a second distinct direction: to the study of semilinear mixed problems. We do this, first, by introducing an operator-theoretic reformulatio...
Complex Langevin: Etiology and Diagnostics of its Main Problem
Aarts, Gert; Seiler, Erhard; Stamatescu, Ion-Olimpiu
2011-01-01
The complex Langevin method is a leading candidate for solving the so-called sign problem occurring in various physical situations. Its most vexing problem is that in some cases it produces `convergence to the wrong limit'. In the first part of the paper we go through the formal justification of the method, identify points at which it may fail and identify a necessary and sufficient criterion for correctness. This criterion would, however, require checking infinitely many identities, and therefore is somewhat academic. We propose instead a truncation to the check of a few identities; this still gives a necessary criterion, but a priori it is not clear whether it remains sufficient. In the second part we carry out a detailed study of two toy models: first we identify the reasons why in some cases the method fails, second we test the efficiency of the truncated criterion and find that it works perfectly at least in the toy models studied.
Overcoming Problems in the Measurement of Biological Complexity
Cebrian, Manuel; Ortega, Alfonso
2010-01-01
In a genetic algorithm, fluctuations of the entropy of a genome over time are interpreted as fluctuations of the information that the genome's organism is storing about its environment, being this reflected in more complex organisms. The computation of this entropy presents technical problems due to the small population sizes used in practice. In this work we propose and test an alternative way of measuring the entropy variation in a population by means of algorithmic information theory, where the entropy variation between two generational steps is the Kolmogorov complexity of the first step conditioned to the second one. As an example application of this technique, we report experimental differences in entropy evolution between systems in which sexual reproduction is present or absent.
Coordinating complex problem-solving among distributed intelligent agents
Adler, Richard M.
1992-01-01
A process-oriented control model is described for distributed problem solving. The model coordinates the transfer and manipulation of information across independent networked applications, both intelligent and conventional. The model was implemented using SOCIAL, a set of object-oriented tools for distributing computing. Complex sequences of distributed tasks are specified in terms of high level scripts. Scripts are executed by SOCIAL objects called Manager Agents, which realize an intelligent coordination model that routes individual tasks to suitable server applications across the network. These tools are illustrated in a prototype distributed system for decision support of ground operations for NASA's Space Shuttle fleet.
The Communication Complexity of the Hamming Distance Problem
Huang, Wei; Shi, Yaoyun; Zhang, Shengyu; Zhu, Yufan
2005-01-01
We investigate the randomized and quantum communication complexity of the Hamming Distance problem, which is to determine if the Hamming distance between two n-bit strings is no less than a threshold d. We prove a quantum lower bound of \\Omega(d) qubits in the general interactive model with shared prior entanglement. We also construct a classical protocol of O(d \\log d) bits in the restricted Simultaneous Message Passing model, improving previous protocols of O(d^2) bits (A. C.-C. Yao, Procee...
Complex space multipole theory for scattering and diffraction problems
Lindell, Ismo V.; Nikoskinen, Keijo I.
1987-01-01
Classical multipole theory can be extended to multipoles located in complex space and applied in scattering and diffraction problems with the advantage that, if the point of the multipole is correctly chosen, the first term may give an order of magnitude better approximation to the source than when the multipole is in real space. The basic theory, given elsewhere, is presented here in a more straightforward manner and the improvement in radiation pattern is demonstrated for sources of constant polarization. Applications on scattering by spheroidal dielectric bodies and diffraction by a dielectric half-space are discussed.
2016-01-01
This book captures current trends and developments in the field of systems thinking and soft operations research which can be applied to solve today's problems of dynamic complexity and interdependency. Such ‘wicked problems’ and messes are seemingly intractable problems characterized as value-laden, ambiguous, and unstable, that resist being tamed by classical problem solving. Actions and interventions associated with this complex problem space can have highly unpredictable and unintended consequences. Examples of such complex problems include health care reform, global climate change, transnational serious and organized crime, terrorism, homeland security, human security, disaster management, and humanitarian aid. Moving towards the development of solutions to these complex problem spaces depends on the lens we use to examine them and how we frame the problem. It will be shown that systems thinking and soft operations research has had great success in contributing to the management of complexity. .
Complex-Dynamical Approach to Cosmological Problem Solution
Kirilyuk, A P
2005-01-01
Universe structure emerges in the unreduced, complex-dynamic interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis, avoiding any perturbative model, gives intrinsically creative cosmology describing the real, explicitly emerging world structure with dynamic randomness on each scale. Without imposing any postulates or additional entities, we obtain physically real, three-dimensional space, irreversibly flowing time, elementary particles with their detailed structure and intrinsic properties, causally complete and unified version of quantum and relativistic behaviour, the origin and number of naturally unified fundamental forces, classical behaviour emergence in a closed system, and true quantum chaos. Major problems of standard cosmology and astrophysics are consistently solved in this extended picture, including those of quantum cosmology and gravity, entropy growth and time arrow, "hierarchy" of elementary particles (Planckian unit...
Energy Technology Data Exchange (ETDEWEB)
White, Signe K.; Kelkar, Sharad M.; Brown, Don W.
2016-03-01
The Geothermal Technologies Office Code Comparison Study (GTO-CCS) was established by the U.S. Department of Energy to facilitate collaboration among members of the geothermal modeling community and to evaluate and improve upon the ability of existing codes to simulate thermal, hydrological, mechanical, and chemical processes associated with complex enhanced geothermal systems (EGS). The first stage of the project, which has been completed, involved comparing simulations for seven benchmark problems that were primarily designed using well-prescribed, simplified data sets. In the second stage, the participating teams are tackling two challenge problems based on the EGS research conducted in hot dry rock (HDR) at Fenton Hill, near Los Alamos, New Mexico. The Fenton Hill project, conducted by Los Alamos National Laboratory (LANL) from 1970 to 1995, was the world’s first HDR demonstration project. One of the criteria for selecting this experiment as the basis for the challenge problems was the amount and availability of data for generating model inputs. The Fenton Hill HDR system consisted of two reservoirs – an earlier Phase I reservoir tested from 1974 to 1981 and a deeper Phase II reservoir tested from 1980 to 1995. Detailed accounts of both phases of the HDR project have been presented in a number of books and reports, including a recently published summary of the lessons learned and a final report with a chronological description of the Fenton Hill project, prepared by LANL. Project documents and records have been archived and made public through the National Geothermal Data System (NGDS). Some of the data acquired from Phase II are available in electronic format readable on modern computers. These include the microseismic data from some of the important experiments (e.g. the massive hydraulic fracturing test conducted in 1983) and the injection/production wellhead data from the circulation tests conducted between 1992-1995. However, much of the data collected
Leppavirta, J.; Kettunen, H.; Sihvola, A.
2011-01-01
Complex multistep problem exercises are one way to enhance engineering students' learning of electromagnetics (EM). This study investigates whether exposure to complex problem exercises during an introductory EM course improves students' conceptual and procedural knowledge. The performance in complex problem exercises is compared to prior success…
Making mobility-related disability better: a complex response to a complex problem
Directory of Open Access Journals (Sweden)
Rockwood Kenneth
2012-10-01
Full Text Available Abstract Mobility disability in older adults can arise from single system problems, such as discrete musculoskeletal injury. In frail older adults, however, mobility disability is part of a complex web of problems. The approach to their rehabilitation must take that complexity into account, as is reported by Fairhall et al. First, their overall health state must be assessed, which is achieved by a comprehensive geriatric assessment. The assessment can show how a particular patient came to be disabled, so that an individualized care plan can be worked out. Whether this approach works in general can be evaluated by looking at group differences in mean mobility test scores. Knowing whether it has worked in the individual patient requires an individualized measure. This is because not every patient starts from the same point, and not every patient achieves success by aiming for the same goal. For one patient, walking unassisted for three metres would be a triumph; for another it would be a tragedy. Unless we understand the complexity of the needs of frail older adults, we will neither be able to treat them effectively nor evaluate our efforts sensibly. Please see related article http://www.biomedcentral.com/1741-7015/10/120
An analytical approach to managing complex process problems
Energy Technology Data Exchange (ETDEWEB)
Ramstad, Kari; Andersen, Espen; Rohde, Hans Christian; Tydal, Trine
2006-03-15
The oil companies are continuously investing time and money to ensure optimum regularity on their production facilities. High regularity increases profitability, reduces workload on the offshore organisation and most important; - reduces discharge to air and sea. There are a number of mechanisms and tools available in order to achieve high regularity. Most of these are related to maintenance, system integrity, well operations and process conditions. However, for all of these tools, they will only be effective if quick and proper analysis of fluids and deposits are carried out. In fact, analytical backup is a powerful tool used to maintain optimised oil production, and should as such be given high priority. The present Operator (Hydro Oil and Energy) and the Chemical Supplier (MI Production Chemicals) have developed a cooperation to ensure that analytical backup is provided efficiently to the offshore installations. The Operator's Research and Development (R and D) departments and the Chemical Supplier have complementary specialties in both personnel and equipment, and this is utilized to give the best possible service when required from production technologists or operations. In order for the Operator's Research departments, Health, Safety and Environment (HSE) departments and Operations to approve analytical work performed by the Chemical Supplier, a number of analytical tests are carried out following procedures agreed by both companies. In the present paper, three field case examples of analytical cooperation for managing process problems will be presented. 1) Deposition in a Complex Platform Processing System. 2) Contaminated Production Chemicals. 3) Improved Monitoring of Scale Inhibitor, Suspended Solids and Ions. In each case the Research Centre, Operations and the Chemical Supplier have worked closely together to achieve fast solutions and Best Practice. (author) (tk)
Eye-Tracking Study of Complexity in Gas Law Problems
Tang, Hui; Pienta, Norbert
2012-01-01
This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…
On the complexity of a bundle pricing problem
Grigoriev, Alexander; Loon, van Joyce; Uetz, Marc
2011-01-01
We consider the problem of pricing items in order to maximize the revenue obtainable from a set of single minded customers. We relate the tractability of the problem to structural properties of customers’ valuations: the problem admits an efficient approximation algorithm, parameterized along the in
Complexity of Decision Problems for Mixed and Modal Specifications
DEFF Research Database (Denmark)
Antonik, Adam; Huth, Michael; Nyman, Ulrik Mathias;
2008-01-01
We consider decision problems for modal and mixed transition systems used as specifications: the common implementation problem (whether a set of specifications has a common implementation), the consistency problem (whether a single specification has an implementation), and the thorough refinement...... problem (whether all implementations of one specification are also implementations of another one). Common implementation and thorough refinement are shown to be PSPACE-hard for modal, and so also for mixed, specifications. Consistency is PSPACE-hard for mixed, while trivial for modal specifications. We...... also supply upper bounds suggesting strong links between these problems....
Tang, Hui; Kirk, John; Pienta, Norbert J.
2014-01-01
This paper includes two experiments, one investigating complexity factors in stoichiometry word problems, and the other identifying students' problem-solving protocols by using eye-tracking technology. The word problems used in this study had five different complexity factors, which were randomly assigned by a Web-based tool that we developed. The…
A note on the Dirichlet problem for model complex partial differential equations
Ashyralyev, Allaberen; Karaca, Bahriye
2016-08-01
Complex model partial differential equations of arbitrary order are considered. The uniqueness of the Dirichlet problem is studied. It is proved that the Dirichlet problem for higher order of complex partial differential equations with one complex variable has infinitely many solutions.
Electromagnetic waves in complex systems selected theoretical and applied problems
Velychko, Lyudmyla
2016-01-01
This book gives guidance to solve problems in electromagnetics, providing both examples of solving serious research problems as well as the original results to encourage further investigations. The book contains seven chapters on various aspects of resonant wave scattering, each solving one original problem. All of them are unified by the authors’ desire to show advantages of rigorous approaches at all stages, from the formulation of a problem and the selection of a method to the interpretation of results. The book reveals a range of problems associated with wave propagation and scattering in natural and artificial environments or with the design of antennas elements. The authors invoke both theoretical (analytical and numerical) and experimental techniques for handling the problems. Attention is given to mathematical simulations, computational efficiency, and physical interpretation of the experimental results. The book is written for students, graduate students and young researchers. .
Asbestos quantification in track ballast, a complex analytical problem
Cavallo, Alessandro
2016-04-01
Track ballast forms the trackbeb upon which railroad ties are laid. It is used to bear the load from the railroad ties, to facilitate water drainage, and also to keep down vegetation. It is typically made of angular crushed stone, with a grain size between 30 and 60 mm, with good mechanical properties (high compressive strength, freeze - thaw resistance, resistance to fragmentation). The most common rock types are represented by basalts, porphyries, orthogneisses, some carbonatic rocks and "green stones" (serpentinites, prasinites, amphibolites, metagabbros). Especially "green stones" may contain traces, and sometimes appreciable amounts of asbestiform minerals (chrysotile and/or fibrous amphiboles, generally tremolite - actinolite). In Italy, the chrysotile asbestos mine in Balangero (Turin) produced over 5 Mt railroad ballast (crushed serpentinites), which was used for the railways in northern and central Italy, from 1930 up to 1990. In addition to Balangero, several other serpentinite and prasinite quarries (e.g. Emilia Romagna) provided the railways ballast up to the year 2000. The legal threshold for asbestos content in track ballast is established in 1000 ppm: if the value is below this threshold, the material can be reused, otherwise it must be disposed of as hazardous waste, with very high costs. The quantitative asbestos determination in rocks is a very complex analytical issue: although techniques like TEM-SAED and micro-Raman are very effective in the identification of asbestos minerals, a quantitative determination on bulk materials is almost impossible or really expensive and time consuming. Another problem is represented by the discrimination of asbestiform minerals (e.g. chrysotile, asbestiform amphiboles) from the common acicular - pseudo-fibrous varieties (lamellar serpentine minerals, prismatic/acicular amphiboles). In this work, more than 200 samples from the main Italian rail yards were characterized by a combined use of XRD and a special SEM
de Leeuw, L.
Sixty-four fifth and sixth-grade pupils were taught number series extrapolation by either an algorithm, fully prescribed problem-solving method or a heuristic, less prescribed method. The trained problems were within categories of two degrees of complexity. There were 16 subjects in each cell of the 2 by 2 design used. Aptitude Treatment…
Variational Problem with Complex Coefficient of a Nonlinear Schrödinger Equation
Indian Academy of Sciences (India)
Nigar Yildirim Aksoy; Bunyamin Yildiz; Hakan Yetiskin
2012-08-01
An optimal control problem governed by a nonlinear Schrödinger equation with complex coefficient is investigated. The paper studies existence, uniqueness and optimality conditions for the control problem.
Problems of empathy. Difficulties of emotive understanding and social complexity.
Directory of Open Access Journals (Sweden)
Maurizio Fabbri
2007-07-01
Full Text Available The Author analyses certain problems concerning the transformation of styles in educational experience. Refering also to neuroscientific studies, more radical model of empaty, that enable the interpretation of historical change, are proposed.
Information Problem Solving: Analysis of a Complex Cognitive Skill
S. Brand-Gruwel; I. Wopereis; Y. Vermetten
2004-01-01
textabstractIn (higher) education students are often faced with information problems: tasks or assignments which require the student to identify information needs, locate corresponding information sources, extract and organize relevant information from each source, and synthesize information from a
A new model for solution of complex distributed constrained problems
Al-Maqtari, Sami; Babkin, Eduard
2010-01-01
In this paper we describe an original computational model for solving different types of Distributed Constraint Satisfaction Problems (DCSP). The proposed model is called Controller-Agents for Constraints Solving (CACS). This model is intended to be used which is an emerged field from the integration between two paradigms of different nature: Multi-Agent Systems (MAS) and the Constraint Satisfaction Problem paradigm (CSP) where all constraints are treated in central manner as a black-box. This model allows grouping constraints to form a subset that will be treated together as a local problem inside the controller. Using this model allows also handling non-binary constraints easily and directly so that no translating of constraints into binary ones is needed. This paper presents the implementation outlines of a prototype of DCSP solver, its usage methodology and overview of the CACS application for timetabling problems.
QUANTUM COMPLEXITY OF THE INTEGRATION PROBLEM FOR ANISOTROPIC CLASSES
Institute of Scientific and Technical Information of China (English)
Xiao-fei Hu; Pei-xin Ye
2005-01-01
We obtain the optimal order of high-dimensional integration complexity in the quantum computation model in anisotropic Sobolev classes Wr∞ ([0, 1]d) and Holder Nikolskii classes Hr∞([0, 1]d). It is proved that for these classes of functions there is a speed-up of quantum algorithms over deterministic classical algorithms due to factor n-1 and over randomized classical methods due to factor n-1/2. Moreover, we give an estimation for optimal query complexity in the class H∧∞ (D) whose smoothness index is the boundary of some complete set in Zd+.
[Problems of formal organizational structure of industrial health care complexes].
Włodarczyk, C
1978-01-01
The author formulates the thesis that the description of organizational structure of industrial health care complex calls for isolation of the following aspects:--structure of territorial links--systemof organizational units and divisions--organization of basic functions--structure of management--structure of supervision of middle and lowe-level personnel--composition of health care complex council--system of accessibility ranges. Each of the above aspects has been considered on the basis of operative rules of law, using organizational analysis methods.
On the complexity of the balanced vertex ordering problem
Directory of Open Access Journals (Sweden)
Jan Kara
2007-01-01
Full Text Available We consider the problem of finding a balanced ordering of the vertices of a graph. More precisely, we want to minimise the sum, taken over all vertices v, of the difference between the number of neighbours to the left and right of v. This problem, which has applications in graph drawing, was recently introduced by Biedl et al. [Discrete Applied Math. 148:27--48, 2005]. They proved that the problem is solvable in polynomial time for graphs with maximum degree three, but NP-hard for graphs with maximum degree six. One of our main results is to close the gap in these results, by proving NP-hardness for graphs with maximum degree four. Furthermore, we prove that the problem remains NP-hard for planar graphs with maximum degree four and for 5-regular graphs. On the other hand, we introduce a polynomial time algorithm that determines whetherthere is a vertex ordering with total imbalance smaller than a fixed constant, and a polynomial time algorithm that determines whether a given multigraph with even degrees has an `almost balanced' ordering.
Complexity of Data Dependence problems for Program Schemas with Concurrency
Danicic, Sebastian; Laurence, Michael R
2010-01-01
The problem of deciding whether one point in a program is data dependent upon another is fundamental to program analysis and has been widely studied. In this paper we consider this problem at the abstraction level of program schemas, in which computations occur in the Herbrand domain of terms and predicate symbols, which represent arbitrary predicate functions, are allowed. Given a vertex l in the flowchart of a schema S having only equality assignments and variables v,w, we show that it is PSPACE-hard to decide whether there exists an execution of a program defined by S in which v holds the initial value of w at at least one occurrence of l on the path of execution, with membership in PSPACE holding provided there is a constant upper bound on the arity of any predicate in S. We also consider the `dual' problem in which v is required to hold the initial value of w at every occurrence of l, for which the analogous results hold. Additionally, the former problem for programs with non-deterministic branching (in ...
Reduced-Complexity Semidefinite Relaxations of Optimal Power Flow Problems
DEFF Research Database (Denmark)
Andersen, Martin Skovgaard; Hansson, Anders; Vandenberghe, Lieven
2014-01-01
We propose a new method for generating semidefinite relaxations of optimal power flow problems. The method is based on chordal conversion techniques: by dropping some equality constraints in the conversion, we obtain semidefinite relaxations that are computationally cheaper, but potentially weaker...
Interpretation Problems in Modelling Complex Artifacts for Diagnosis
DEFF Research Database (Denmark)
Lind, Morten
1996-01-01
The paper analyse the interpretation problems involved in building models for diagnosis of industrial systems. It is shown that the construction of a fault tree of a plant is based on general diagnostic knowledge and an extensive body of plant knowledge. It is also shown that the plant knowledge ...
2005-01-01
We study the connection between the order of phase transitions in combinatorial problems and the complexity of decision algorithms for such problems. We rigorously show that, for a class of random constraint satisfaction problems, a limited connection between the two phenomena indeed exists. Specifically, we extend the definition of the spine order parameter of Bollobas et al. to random constraint satisfaction problems, rigorously showing that for such problems a discontinuity of the spine is...
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
In this paper,authors discuss the numerical methods of general discontinuous boundary value problems for elliptic complex equations of first order.They first give the well posedness of general discontinuous boundary value problems,reduce the discontinuousboundary value problems to a variation problem,and then find the numerical solutions ofabove problem by the finite element method.Finally authors give some error-estimates of the foregoing numerical solutions.
Andajani-Sutjahjo, Sari; Manderson, Lenore; Astbury, Jill
2007-03-01
In this article, we explore how Javanese women identify and speak of symptoms of depression in late pregnancy and early postpartum and describe their subjective accounts of mood disorders. The study, conducted in the East Java region of Indonesia in 2000, involved in-depth interviews with a subgroup of women (N = 41) who scored above the cutoff score of 12/13 on the Edinburgh Postnatal Depression Scale (EPDS) during pregnancy, at six weeks postpartum, or on both occasions. This sample was taken from a larger cohort study (N cohort = 488) researching the sociocultural factors that contribute to women's emotional well-being in early motherhood. The women used a variety of Indonesian and Javanese terms to explain their emotional states during pregnancy and in early postpartum, some of which coincided with the feelings described on the EPDS and others of which did not. Women attributed their mood variations to multiple causes including: premarital pregnancy, chronic illness in the family, marital problems, lack of support from partners or family networks, their husband's unemployment, and insufficient family income due to giving up their own paid work. We argue for the importance of understanding the context of childbearing in order to interpret the meaning of depression within complex social, cultural, and economic contexts.
Games that Enlist Collective Intelligence to Solve Complex Scientific Problems
Directory of Open Access Journals (Sweden)
Stephen Burnett
2015-09-01
Full Text Available There is great value in employing the collective problem-solving power of large groups of people. Technological advances have allowed computer games to be utilized by a diverse population to solve problems. Science games are becoming more popular and cover various areas such as sequence alignments, DNA base-pairing, and protein and RNA folding. While these tools have been developed for the general population, they can also be used effectively in the classroom to teach students about various topics. Many games also employ a social component that entices students to continue playing and thereby to continue learning. The basic functions of game play and the potential of game play as a tool in the classroom are discussed in this article.
Games that Enlist Collective Intelligence to Solve Complex Scientific Problems.
Burnett, Stephen; Furlong, Michelle; Melvin, Paul Guy; Singiser, Richard
2016-03-01
There is great value in employing the collective problem-solving power of large groups of people. Technological advances have allowed computer games to be utilized by a diverse population to solve problems. Science games are becoming more popular and cover various areas such as sequence alignments, DNA base-pairing, and protein and RNA folding. While these tools have been developed for the general population, they can also be used effectively in the classroom to teach students about various topics. Many games also employ a social component that entices students to continue playing and thereby to continue learning. The basic functions of game play and the potential of game play as a tool in the classroom are discussed in this article.
Complex Behaviour for the Origin and Destination Matrix Estimation Problem
Institute of Scientific and Technical Information of China (English)
SUN Hui-Jun; WU Jian-Jun
2006-01-01
@@ The origin and destination (O-D) matrix estimation is an important problem in traffic networks. We apply the gravitation model to express the preference attachment and to analyse the statistical characteristics of the traffic flow in each O-D pair in theory. It is found that the distribution of the future O-D matrix decays as a power law.Additionally, different exponents are obtained for both the constant and variable link cost.
On the Complexity of the Asymmetric VPN Problem
Rothvoß, Thomas; Sanità, Laura
We give the first constant factor approximation algorithm for the asymmetric Virtual Private Network (textsc{Vpn}) problem with arbitrary concave costs. We even show the stronger result, that there is always a tree solution of cost at most 2·OPT and that a tree solution of (expected) cost at most 49.84·OPT can be determined in polynomial time.
Making Sense of Complex Problems: A Resource for Teams
2015-12-01
frustration include: • Providing images or illustrations that depict ambiguity, confusion, or the “ fuzzy front end ” of problem definition while...ISBN-13: 978-1591844594 Title: Convivial toolbox: Generative research for the front end of design Author: E. Sanders and P. Stappers ISBN-10...Recruiting or selecting team members. Interview participants indicated that although the team leader may have a significant say in who ends up on
Presenilins and the γ-secretase: still a complex problem
Directory of Open Access Journals (Sweden)
Small David H
2010-02-01
Full Text Available Abstract The presenilins form part of a complex of membrane proteins that are involved in the proteolytic cleavage of cell-surface molecules. This article reviews the history of the discovery of the presenilins, their role in the pathogenesis of Alzheimer's disease and in the metabolism of the amyloid-β precursor protein. Unanswered questions about their biochemical mechanism of action and their effects on Ca2+ homeostasis are examined.
Complexity Analysis of Pipeline Mapping Problems in Distributed Heterogeneous Networks
Gu, Yi; Wu, Qishi; Zhu, Mengxia; Nageswara S. V. Rao
2009-01-01
Largescale scientific applications require using various system resources to execute complex computing pipelines in distributed networks to support collaborative research. System resources are typically shared in the Internet or over dedicated connections based on their location, availability, capability, and capacity. Optimizing the network performance of computing pipelines in such distributed environments is critical to the success of these applications.We consider two types of largescale ...
Problem-oriented stereo vision quality evaluation complex
Sidorchuk, D.; Gusamutdinova, N.; Konovalenko, I.; Ershov, E.
2015-12-01
We describe an original low cost hardware setting for efficient testing of stereo vision algorithms. The method uses a combination of a special hardware setup and mathematical model and is easy to construct, precise in applications of our interest. For a known scene we derive its analytical representation, called virtual scene. Using a four point correspondence between the scene and virtual one we compute extrinsic camera parameters, and project virtual scene on the image plane, which is the ground truth for depth map. Another result, presented in this paper, is a new depth map quality metric. Its main purpose is to tune stereo algorithms for particular problem, e.g. obstacle avoidance.
Managing complex orthodontic problems: the use of implants for anchorage.
Kokich, V G
1996-06-01
Today implants are commonly used to replace missing teeth in partially edentulous adult orthodontic patients. Because these patients are missing teeth, orthodontic mechanics may be complicated or often impossible because of insufficient anchorage. In these situations, it may be feasible to use the implant initially as an orthodontic anchor to facilitate complex tooth movement and secondarily as an abutment for a crown or fixed prosthesis. This article will discuss the ramifications and requirements for using implants as anchors and abutments in adult orthodontic patients.
Resolving the Complexity of Some Data Privacy Problems
Blocki, Jeremiah
2010-01-01
We formally study two methods for data sanitation that have been used extensively in the database community: k-anonymity and l-diversity. We settle several open problems concerning the difficulty of applying these methods optimally, proving both positive and negative results: 1. 2-anonymity is in P. 2. The problem of partitioning the edges of a triangle-free graph into 4-stars (degree-three vertices) is NP-hard. This yields an alternative proof that 3-anonymity is NP-hard even when the database attributes are all binary. 3. 3-anonymity with only 27 attributes per record is MAX SNP-hard. 4. For databases with n rows, k-anonymity is in O(4^n poly(n)) time for all k > 1. 5. For databases with n rows and l <= log_{2c+2} log n attributes over an alphabet of cardinality c = O(1), k-anonymity is in P. Assuming c, l = O(1), k-anonymity is in O(n). 6. 3-diversity with binary attributes is NP-hard, with one sensitive attribute. 7. 2-diversity with binary attributes is NP-hard, with three sensitive attributes.
Fixed parameter complexity of distance constrained labeling and uniform channel assignment problems
Fiala, Jiří; Gavenčiak, Tomáš; Knop, Dušan; Koutecký, Martin; Kratochvíl, Jan
2015-01-01
We study computational complexity of the class of distance-constrained graph labeling problems from the fixed parameter tractability point of view. The parameters studied are neighborhood diversity and clique width. We rephrase the distance constrained graph labeling problem as a specific uniform variant of the Channel Assignment problem and show that this problem is fixed parameter tractable when parameterized by the neighborhood diversity together with the largest weight. Consequently, ever...
The solution of the optimization problem of small energy complexes using linear programming methods
Ivanin, O. A.; Director, L. B.
2016-11-01
Linear programming methods were used for solving the optimization problem of schemes and operation modes of distributed generation energy complexes. Applicability conditions of simplex method, applied to energy complexes, including installations of renewable energy (solar, wind), diesel-generators and energy storage, considered. The analysis of decomposition algorithms for various schemes of energy complexes was made. The results of optimization calculations for energy complexes, operated autonomously and as a part of distribution grid, are presented.
Markov Renewal Methods in Restart Problems in Complex Systems
DEFF Research Database (Denmark)
Asmussen, Søren; Lipsky, Lester; Thompson, Stephen
A task with ideal execution time L such as the execution of a computer program or the transmission of a file on a data link may fail, and the task then needs to be restarted. The task is handled by a complex system with features similar to the ones in classical reliability: failures may...... be mitigated by using server redundancy in parallel or k-out-of-n arrangements, standbys may be cold or warm, one or more repairmen may take care of failed components, etc. The total task time X (including restarts and pauses in failed states) is investigated with particular emphasis on the tail P(X > x......). A general alternating Markov renewal model is proposed and an asymptotic exponential form P(X > x) ∼ Ce−γx identified for the case of a deterministic task time L ≡ `. The rate γ is given by equating the spectral radius of a certain matrix to 1, and the asymptotic form of γ = γ(`) as ` → ∞ is derived...
Beyond pure parasystole: promises and problems in modeling complex arrhythmias.
Courtemanche, M; Glass, L; Rosengarten, M D; Goldberger, A L
1989-08-01
The dynamics of pure parasystole, a cardiac arrhythmia in which two competing pacemakers fire independently, have recently been fully characterized. This model is now extended in an attempt to account for the more complex dynamics occurring with modulated parasystole, in which there exists nonlinear interaction between the sinus node and the ectopic ventricular focus. Theoretical analysis of modulated parasystole reveals three types of dynamics: entrainment, quasiperiodicity, and chaos. Rhythms associated with quasiperiodicity obey a set of rules derived from pure parasystole. This model is applied to the interpretation of continuous electrocardiographic data sets from three patients with complicated patterns of ventricular ectopic activity. We describe several new statistical properties of these records, related to the number of intervening sinus beats between ectopic events, that are essential in characterizing the dynamics and testing mathematical models. Detailed comparison between data and theory in these cases show substantial areas of agreement as well as potentially important discrepancies. These findings have implications for understanding the dynamics of the heartbeat in normal and pathological conditions.
Nonlinear problems of complex natural systems: Sun and climate dynamics
Bershadskii, A
2012-01-01
Universal role of the nonlinear one-third subharmonic resonance mechanism in generation of the strong fluctuations in such complex natural dynamical systems as global climate and global solar activity is discussed using wavelet regression detrended data. Role of the oceanic Rossby waves in the year-scale global temperature fluctuations and the nonlinear resonance contribution to the El Nino phenomenon have been discussed in detail. The large fluctuations of the reconstructed temperature on the millennial time-scales (Antarctic ice cores data for the past 400,000 years) are also shown to be dominated by the one-third subharmonic resonance, presumably related to Earth precession effect on the energy that the intertropical regions receive from the Sun. Effects of Galactic turbulence on the temperature fluctuations are discussed in this content. It is also shown that the one-third subharmonic resonance can be considered as a background for the 11-years solar cycle, and again the global (solar) rotation and chaoti...
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper deals with boundary value problems for linear uniformly elliptic systems. First the general linear uniformly elliptic system of the first order equations is reduced to complex form, and then the compound boundary value problem for the complex equations of the first order is discussed. The approximate solutions of the boundary value problem are found by the variation-difference method, and the error estimates for the approximate solutions are derived.Finally the approximate method of the oblique derivative problem for linear uniformly elliptic equations of the second or der is introduced.
Graves, Donald H.
2000-01-01
A focus on people--whether community members, students, historical figures, or fictional characters--and their motivations brings excitement to learning. A community's experts on everything from jazz music and Chinese tapestries to building construction can help students move inside history and other subjects. (MLH)
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper presents an infeasible-interior-point algorithm for aclass of nonmonotone complementarity problems, and analyses its convergence and computational complexity. The results indicate that the proposed algorithm is a polynomial-time one.
Fostering Creative Problem Solvers in Higher Education: A Response to Complexity of Societies
DEFF Research Database (Denmark)
2016-01-01
Recent studies have emphasized issues of social emergence based on thinking of societies as complex systems. The complexity of professional practice has been recognized as the root of challenges for higher education. To foster creative problem solvers is a key response of higher education in order...... to meet such challenges. This chapter aims to illustrate how to understand: 1) complexity as the nature of professional practice; 2) creative problem solving as the core skill in professional practice; 3) creativity as interplay between persons and their environment; 4) higher education as the context...... of fostering creative problem solvers; and 5) some innovative strategies such as Problem-Based Learning (PBL) and building a learning environment by Information Communication Technology (ICT) as potential strategies of creativity development. Accordingly, this chapter contributes to bridge the complexity...
Kirilyuk, Andrei P
2012-01-01
We review the recently proposed unreduced, complex-dynamical solution to many-body problem with arbitrary interaction and its application to unified solution of fundamental problems, including foundations of causally complete quantum mechanics, relativity, particle properties and cosmology. We first analyse the universal properties of many-body problem solution without any perturbative reduction and show that the emerging new quality of fundamental dynamic multivaluedness (or redundance) of resulting system configuration leads to universal concept of dynamic complexity, chaoticity and fractality of any real system behaviour. We then consider unified features of this complex dynamics. Applications of that universal description to systems at various complexity levels have been performed and in this paper we review those at the lowest, fundamental complexity levels leading to causal understanding of unified origins of quantum mechanics, relativity (special and general), elementary particles, their intrinsic prop...
Nasini, Stefano
2015-01-01
The thesis deals with the theoretical and practical study of mathematical programming methodologies to the analysis complex networks and their application in economic and social problems. More specifically, it applies models and methods for solving linear and integer programming problems to network models exploiting the matrix structure of such models, resulting in efficient computational procedures and small processing time. As a consequence, it allows the study of larger and more complex n...
Child outcomes of home-visiting for families with complex and multiple problems
van Assen, Arend; Dickscheit, Jana; Post, Wendy; Grietens, Hans
2016-01-01
Introduction Families with complex and multiple problems are faced with an accumulation of problems across multiple areas of life. Furthermore, these families are often considered to be ‘difficult to treat’. Children and teenagers growing up in these families are exposed to an accumulation of risks
A Real-Life Case Study of Audit Interactions--Resolving Messy, Complex Problems
Beattie, Vivien; Fearnley, Stella; Hines, Tony
2012-01-01
Real-life accounting and auditing problems are often complex and messy, requiring the synthesis of technical knowledge in addition to the application of generic skills. To help students acquire the necessary skills to deal with these problems effectively, educators have called for the use of case-based methods. Cases based on real situations (such…
The information-based complexity of approximation problem by adaptive Monte Carlo methods
Institute of Scientific and Technical Information of China (English)
2008-01-01
In this paper, we study the complexity of information of approximation problem on the multivariate Sobolev space with bounded mixed derivative MWpr,α(Td), 1 < p < ∞, in the norm of Lq(Td), 1 < q < ∞, by adaptive Monte Carlo methods. Applying the discretization technique and some properties of pseudo-s-scale, we determine the exact asymptotic orders of this problem.
Institute of Scientific and Technical Information of China (English)
Fang Gensun; Ye Peixin
2005-01-01
The order of computational complexity of all bounded linear functional approximation problem is determined for the generalized Sobolev class Wp∧(Id), Nikolskii class Hk∞(Id) in the worst (deterministic), stochastic and average case setting, from which it is concluded that the bounded linear functional approximation problem for the classes stochastic and average case setting.
The Streaming Complexity of Cycle Counting, Sorting by Reversals, and Other Problems
DEFF Research Database (Denmark)
Verbin, Elad; Yu, Wei
2011-01-01
by Gavinsky et al. to prove an exponential separation between quantum communication complexity and one-way randomized communication complexity. We are the first to introduce BHH, and to prove a lower bound for it. The hardness of the BHH problem is inherently oneway: it is easy to solve BHH using logarithmic...
Health-related problems and quality of life in patients with syndromic and complex craniosynostosis
T. de Jong (Tim); M. Maliepaard (Marianne); N. Bannink (Natalja); H. Raat (Hein); I.M.J. Mathijssen (Irene)
2012-01-01
textabstractPurpose: We conducted this study to gauge the health-related problems, quality of life and the performance of the Health Utility Index Mark 3 (HUI-3) in patients with syndromic and complex craniosynostosis. Patients with syndromic and complex craniosynostosis have various physical and me
Cotta, R. M.; Naveira-Cotta, C. P.; Knupp, D. C.; Zotin, J. L. Z.; Pontes, P. C.
2016-09-01
This lecture offers an updated review on the Generalized Integral Transform Technique (GITT), with focus on handling complex geometries, coupled problems, and nonlinear convection-diffusion, so as to illustrate some new application paradigms. Special emphasis is given to demonstrating novel developments, such as a single domain reformulation strategy that simplifies the treatment of complex geometries, an integral balance scheme in handling multiscale problems, the adoption of convective eigenvalue problems in dealing with strongly convective formulations, and the direct integral transformation of nonlinear convection-diffusion problems based on nonlinear eigenvalue problems. Representative application examples are then provided that employ recent extensions on the Generalized Integral Transform Technique (GITT), and a few numerical results are reported to illustrate the convergence characteristics of the proposed eigenfunction expansions.
Nuclear three-body problem in the complex energy plane: Complex-Scaling-Slater method
Kruppa, A T; Nazarewicz, W; Michel, N
2013-01-01
The physics of open quantum systems is an interdisciplinary area of research. The nuclear "openness" manifests itself through the presence of the many-body continuum representing various decay, scattering, and reaction channels. As the radioactive nuclear beam experimentation extends the known nuclear landscape towards the particle drip lines, the coupling to the continuum space becomes exceedingly more important. Of particular interest are weakly bound and unbound nuclear states appearing around particle thresholds. Theories of such nuclei must take into account their open quantum nature. To describe open quantum systems, we introduce a Complex Scaling (CS) approach in the Slater basis. We benchmark it with the complex-energy Gamow Shell Model (GSM) by studying energies and wave functions of the bound and unbound states of the two-neutron halo nucleus 6He viewed as an $\\alpha$+ n + n cluster system. In the CS approach, we use the Slater basis, which exhibits the correct asymptotic behavior at large distances...
Steen-Eibensteiner, Janice Lee
2006-07-01
A strong science knowledge base and problem solving skills have always been highly valued for employment in the science industry. Skills currently needed for employment include being able to problem solve (Overtoom, 2000). Academia also recognizes the need for effectively teaching students to apply problem solving skills in clinical settings. This thesis investigates how students solve complex science problems in an academic setting in order to inform the development of problem solving skills for the workplace. Students' use of problem solving skills in the form of learned concepts and procedural knowledge was studied as students completed a problem that might come up in real life. Students were taking a community college sophomore biology course, Human Anatomy & Physiology II. The problem topic was negative feedback inhibition of the thyroid and parathyroid glands. The research questions answered were (1) How well do community college students use a complex of conceptual knowledge when solving a complex science problem? (2) What conceptual knowledge are community college students using correctly, incorrectly, or not using when solving a complex science problem? (3) What problem solving procedural knowledge are community college students using successfully, unsuccessfully, or not using when solving a complex science problem? From the whole class the high academic level participants performed at a mean of 72% correct on chapter test questions which was a low average to fair grade of C-. The middle and low academic participants both failed (F) the test questions (37% and 30% respectively); 29% (9/31) of the students show only a fair performance while 71% (22/31) fail. From the subset sample population of 2 students each from the high, middle, and low academic levels selected from the whole class 35% (8/23) of the concepts were used effectively, 22% (5/23) marginally, and 43% (10/23) poorly. Only 1 concept was used incorrectly by 3/6 of the students and identified as
The bright side of being blue: depression as an adaptation for analyzing complex problems.
Andrews, Paul W; Thomson, J Anderson
2009-07-01
Depression is the primary emotional condition for which help is sought. Depressed people often report persistent rumination, which involves analysis, and complex social problems in their lives. Analysis is often a useful approach for solving complex problems, but it requires slow, sustained processing, so disruption would interfere with problem solving. The analytical rumination hypothesis proposes that depression is an evolved response to complex problems, whose function is to minimize disruption and sustain analysis of those problems by (a) giving the triggering problem prioritized access to processing resources, (b) reducing the desire to engage in distracting activities (anhedonia), and (c) producing psychomotor changes that reduce exposure to distracting stimuli. As processing resources are limited, sustained analysis of the triggering problem reduces the ability to concentrate on other things. The hypothesis is supported by evidence from many levels-genes, neurotransmitters and their receptors, neurophysiology, neuroanatomy, neuroenergetics, pharmacology, cognition, behavior, and efficacy of treatments. In addition, the hypothesis provides explanations for puzzling findings in the depression literature, challenges the belief that serotonin transmission is low in depression, and has implications for treatment.
Lemetti, Paul
2005-06-01
Bringing science to business seems rather straight forward. Technology is constantly moving forward and new inventions are being brought into the market place. Science parks and technology parks have sprung out all around the globe competing against each other and trying to keep their own doors open by bringing in new business, thereby creating much needed income to keep their operations moving forward. However, only a small handful ofthese centers around the world can truly be considered successful. It is the relationship between the scientists, start-up business, local universities, local government, and invited bigger business that allows the parks to succeed. The individual scientist wishing to enter into business or just hoping to get his invention into the pool of potential ideas; which might end up in the hands of an entrepreneur or an established company, is not always that simple. Universal success principles must be embraced to ensure success. One must believe in oneself and to strive for excellence. One must be able to see the other persons viewpoint and adapt and change his behavior in order to succeed. One must learn to create trust as well as learn to trust. Furthermore, one must learn to focus on the why of the process and not on the how. A market must be identified and benefits of local area must be sold to potential investor or business partners. A local success has in part to do with local cooperation.
A new complex variable meshless method for transient heat conduction problems
Institute of Scientific and Technical Information of China (English)
Wang Jian-Fei; Cheng Yu-Min
2012-01-01
In this paper,based on the improved complex variable moving least-square (ICVMLS) approximation,a new complex variable meshless method (CVMM) for two-dimensional (2D) transient heat conduction problems is presented.The variational method is employed to obtain the discrete equations,and the essential boundary conditions are imposed by the penalty method.As the transient heat conduction problems are related to time,the Crank-Nicolson difference scheme for two-point boundary value problems is selected for the time discretization.Then the corresponding formulae of the CVMM for 2D heat conduction problems are obtained.In order to demonstrate the applicability of the proposed method,numerical examples are given to show the high convergence rate,good accuracy,and high efficiency of the CVMM presented in this paper.
Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem
Institute of Scientific and Technical Information of China (English)
2008-01-01
The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.
Medicines counterfeiting is a complex problem: a review of key challenges across the supply chain.
Tremblay, Michael
2013-02-01
The paper begins by asking why there is a market for counterfeit medicines, which in effect creates the problem of counterfeiting itself. Contributing factors include supply chain complexity and the lack of whole-systems thinking. These two underpin the author's view that counterfeiting is a complex (i.e. wicked) problem, and that corporate, public policy and regulatory actions need to be mindful of how their actions may be causal. The paper offers a problem-based review of key components of this complexity, viz., the knowledge end-users/consumers have of medicines; whether restrictive information policies may hamper information provision to patients; the internet's direct access to consumers; internet-enabled distribution of unsafe and counterfeit medicines; whether the internet is a parallel and competitive supply chain to legitimate routes; organised crime as an emerging medicines manufacturer and supplier and whether substandard medicines is really the bigger problem. Solutions respect the perceived complexity of the supply chain challenges. The paper identifies the need to avoid technologically-driven solutions, calling for 'technological agnosticism'. Both regulation and public policy need to reflect the dynamic nature of the problem and avoid creating perverse incentives; it may be, for instance, that medicines pricing and reimbursement policies, which affect consumer/patient access may act as market signals to counterfeiters, since this creates a cash market in cheaper drugs.
The information-based complexity of approximation problem by adaptive Monte Carlo methods
Institute of Scientific and Technical Information of China (English)
FANG GenSun; DUAN LiQin
2008-01-01
In this paper,we study the complexity of information of approximation problem on the multivariate Sobolev space with bounded mixed derivative MWTp,α(Td),1＜p＜∞,in the norm of Lq(Td),1＜q＜∞,by adaptive Monte Carlo methods.Applying the discretization technique and some properties of pseudo-s-scale,we determine the exact asymptotic orders of this problem.
Computational complexity of classical problems for hereditary clique-helly graphs
Flavia Bonomo; Guillermo Durán
2004-01-01
A graph is clique-Helly when its cliques satisfy the Helly property. A graph is hereditary clique-Helly when every induced subgraph of it is clique-Helly. The decision problems associated to the stability, chromatic, clique and clique-covering numbers are NP-complete for clique-Helly graphs. In this note, we analyze the complexity of these problems for hereditary clique-Helly graphs. Some of them can be deduced easily by known results. We prove that the clique-covering problem remains NP-comp...
Stability of Complex-Rotation Method on a Simple Resonant Scattering Problem
Institute of Scientific and Technical Information of China (English)
SHEN Li; WANG Lei; LIU Xiao-Jun; SHI Ting-Yun; LIU Hong-Ping
2008-01-01
@@ The stability of the complex-rotation method in B-spline basis for a simple atomic resonant scattering problem in free field is investigated. The numerical calculation shows that this method has a feature that the solution will not change in a wide range of rotation angle θ. Our determined scattering resonant energies and widths exactly coincide with the popularly accepted values. A new resonance is identified numerically although it is very broad.The norm of the complex eigenvalue, [E], is proposed to investigate and to evaluate the stability of the obtained complex eigenvalues.
Sharts-Hopko, Nancy C
2013-01-01
The mandate for evidence-based practice (EBP) arose in response to, among other catalysts, several Institute of Medicine reports beginning in the late 1990s. At the same time, the National Institutes of Health and others have recognized that the most complex, important, and challenging problems, termed "wicked problems," are inherently transdisciplinary and require thinking beyond the limits of existing theories. When nursing students are prepared for EBP, they operate within a fairly stable set of assumptions and they exercise a past orientation. Wicked problem-solving occurs within a context that is characterized as dynamic and ambiguous and requires a future orientation to imagine potential solutions to questions of "what if?" Both skills, EBP, and wicked problem-solving, are essential within the discipline of nursing. Students at all levels need to understand when each scientific approach is required. PhD students must be prepared to participate in wicked problem-solving.
On the Critical Behaviour, Crossover Point and Complexity of the Exact Cover Problem
Morris, Robin D.; Smelyanskiy, Vadim N.; Shumow, Daniel; Koga, Dennis (Technical Monitor)
2003-01-01
Research into quantum algorithms for NP-complete problems has rekindled interest in the detailed study a broad class of combinatorial problems. A recent paper applied the quantum adiabatic evolution algorithm to the Exact Cover problem for 3-sets (EC3), and provided an empirical evidence that the algorithm was polynomial. In this paper we provide a detailed study of the characteristics of the exact cover problem. We present the annealing approximation applied to EC3, which gives an over-estimate of the phase transition point. We also identify empirically the phase transition point. We also study the complexity of two classical algorithms on this problem: Davis-Putnam and Simulated Annealing. For these algorithms, EC3 is significantly easier than 3-SAT.
Directory of Open Access Journals (Sweden)
I. Alhama
2014-01-01
Full Text Available The nondimensionalization of the equations governing a given problem is a direct, relatively easy, and low-cost way to provide interesting information, the dimensionless groups that rule the problem and define its final patterns of solution. In complex problems, however, this technique frequently does not provide the precise and complete set of monomials we are looking for. The use of discrimination in the process of nondimensionalization, the detailed application of which is explained in this paper, always leads to a minimum set of parameters, which, separately, determine the solution of the problems. In addition, the physical meaning and order of magnitude of these discriminated monomials are also provided by the discrimination. The technique is applied to the coupled problem of natural convection between horizontal plates heated from below, containing an anisotropic porous medium.
Learning about Complex Multi-Stakeholder Issues: Assessing the Visual Problem Appraisal
Witteveen, L.M.; Put, M.; Leeuwis, C.
2010-01-01
This paper presents an evaluation of the visual problem appraisal (VPA) learning environment in higher education. The VPA has been designed for the training of competences that are required in complex stakeholder settings in relation to sustainability issues. The design of VPA incorporates a diversi
A Viscosity Approach to the Dirichlet Problem for Complex Monge-Amp\\`ere Equations
Wang, Yu
2010-01-01
The Dirichlet problem for complex Monge-Amp\\'ere equations with continuous data is considered. In particular, a notion of viscosity solutions is introduced; a comparison principle and a solvability theorem are proved; the equivalence between viscosity and pluripotential solutions is established; and an ABP-type of $L^{\\infty}$-estimate is achieved.
Kartal, Ozgul; Dunya, Beyza Aksu; Diefes-Dux, Heidi A.; Zawojewski, Judith S.
2016-01-01
Critical to many science, technology, engineering, and mathematics (STEM) career paths is mathematical modeling--specifically, the creation and adaptation of mathematical models to solve problems in complex settings. Conventional standardized measures of mathematics achievement are not structured to directly assess this type of mathematical…
A method for evaluating the problem complex of choosing the ventilation system for a new building
DEFF Research Database (Denmark)
Hviid, Christian Anker; Svendsen, Svend
2007-01-01
The application of a ventilation system in a new building is a multidimensional complex problem that involves quantifiable and non-quantifiable data like energy consump¬tion, indoor environment, building integration and architectural expression. This paper presents a structured method for evaluat...
Ecosystem services and cooperative fisheries research to address a complex fishery problem
The St. Louis River represents a complex fishery management problem. Current fishery management goals have to be developed taking into account bi-state commercial, subsistence and recreational fisheries which are valued for different characteristics by a wide range of anglers, as...
Shopping Context and Consumers' Mental Representation of Complex Shopping Trip Decision Problems
B.G.C. Dellaert (Benedict); T.A. Arentze (Theo); H.J.P. Timmermans (Harry)
2008-01-01
textabstractDepending on the shopping context, consumers may develop different mental representations of complex shopping trip decision problems to help them interpret the decision situation that they face and evaluate alternative courses of action. To investigate these mental representations and h
An Iterative Layered Tabu Search Algorithm for Complex Job Shop Scheduling Problem
Institute of Scientific and Technical Information of China (English)
LIUMin; DONGMingyu; WUCheng
2005-01-01
In this paper, aiming at the complex characteristics that there exist two interrelated decision processes: job-assignment decision and job-sequencing decision in the complex job shop scheduling problem with parallel machines and technical constraints, we propose an Iterative layered tabu search algorithm (ILTSA), which combines the iterative and layered mechanism with tabu search algorithm. In ILTSA, we define the notation of the optimization layer including the job-assignment optimization layer and the job-sequencing optimization layer which correspond to the above two interrelated decision processes respectively. On the basis, we use the corresponding tabu search algorithms in different optimization layers and switch iteratively the above two tabu search algorithms between the two optimization layers to improve the performance of the scheduling algorithm effectively. In the above two TS algorithms, the measuring functions are the objective of the whole scheduling problem. At last, we make numerical computations for different scale scheduling problems of minimizing the makespan and minimizing the total number of tardy jobs respectively, and numerical computational results show that ILTSA is very efficient and suitable for solving larger scale job shop scheduling problem with parallel machines and technical constraints. Also, we apply successfully ILTSA to a practical complex job shop scheduling problem with parallel machines and technical constraints in one of the largest cotton colored weaving enterprises in China.
Institute of Scientific and Technical Information of China (English)
付铅生; 李帮义
2004-01-01
The complexity status of Pendants-median spanning tree problem is an open problem. Using the complexity of the X3C problem, the paper proves that Pendants-median spanning tree problem is NP-complete. Global-median spanning tree problem is a related problem. Using the complexity of 3SAT, the paper proves that this problem is also NP-complete, and a polynomial -time algorithm to this problem is given, whose time complexity is O(n3).
Watts, C
1999-01-01
Robert Cailliau argues that the explosion of advertising on the web is limiting its' usefulness. He suggests that 'licensing' users may be the only way to stop additional problems such as pornography, spam email and viruses (1 page).
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
As an important tool for heuristic design of NP-hard problems, backbone analysis has become a hot spot in theoretical computer science in recent years. Due to the difficulty in the research on computational complexity of the backbone, many researchers analyzed the backbone by statistic ways. Aiming to increase the backbone size which is usually very small by the existing methods, the unique optimal solution instance construction (UOSIC) is proposed for the graph bi-partitioning problem (GBP). Also, we prove by using the UOSIC that it is NP-hard to obtain the backbone, i.e. no algorithm exists to obtain the backbone of a GBP in polynomial time under the assumption that P ( NP. Our work expands the research area of computational complexity of the backbone. And the UOSIC provides a new way for heuristic design of NP-hard problems.
Numerical nonlinear complex geometrical optics algorithm for the 3D Calderón problem
DEFF Research Database (Denmark)
Delbary, Fabrice; Knudsen, Kim
2014-01-01
The Calderon problem is the mathematical formulation of the inverse problem in Electrical Impedance Tomography and asks for the uniqueness and reconstruction of an electrical conductivity distribution in a bounded domain from the knowledge of the Dirichlet-to-Neumann map associated to the general...... to the simpler approximations. In addition, convergence of the numerical solution towards the exact solution of the boundary integral equation is proved....... to the generalized Laplace equation. The 3D problem was solved in theory in late 1980s using complex geometrical optics solutions and a scattering transform. Several approximations to the reconstruction method have been suggested and implemented numerically in the literature, but here, for the first time, a complete...... computer implementation of the full nonlinear algorithm is given. First a boundary integral equation is solved by a Nystrom method for the traces of the complex geometrical optics solutions, second the scattering transform is computed and inverted using fast Fourier transform, and finally a boundary value...
A complex variable meshless local Petrov-Galerkin method for transient heat conduction problems
Institute of Scientific and Technical Information of China (English)
Wang Qi-Fang; Dai Bao-Dong; Li Zhen-Feng
2013-01-01
On the basis of the complex variable moving least-square (CVMLS) approximation,a complex variable meshless local Petrov-Galerkin (CVMLPG) method is presented for transient heat conduction problems.The method is developed based on the CVMLS approximation for constructing shape functions at scattered points,and the Heaviside step function is used as a test function in each sub-domain to avoid the need for a domain integral in symmetric weak form.In the construction of the well-performed shape function,the trial function of a two-dimensional (2D) problem is formed with a one-dimensional (1 D) basis function,thus improving computational efficiency.The numerical results are compared with the exact solutions of the problems and the finite element method (FEM).This comparison illustrates the accuracy as well as the capability of the CVMLPG method.
The complex variable reproducing kernel particle method for elasto-plasticity problems
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
On the basis of reproducing kernel particle method(RKPM),using complex variable theory,the complex variable reproducing kernel particle method(CVRKPM) is discussed in this paper.The advantage of the CVRKPM is that the correction function of a two-dimensional problem is formed with one-dimensional basis function when the shape function is formed.Then the CVRKPM is applied to solve two-dimensional elasto-plasticity problems.The Galerkin weak form is employed to obtain the discretized system equation,the penalty method is used to apply the essential boundary conditions.And then,the CVRKPM for two-dimensional elasto-plasticity problems is formed,the corresponding formulae are obtained,and the Newton-Raphson method is used in the numerical implementation.Three numerical examples are given to show that this method in this paper is effective for elasto-plasticity analysis.
Solving A Kind of High Complexity Multi-Objective Problems by A Fast Algorithm
Institute of Scientific and Technical Information of China (English)
Zeng San-you; Ding Li-xin; Kang Li-shan
2003-01-01
A fast algorithm is proposed to solve a kind of high complexity multi-objective problems in this paper. It takes advantages of both the orthogonal design method to search evenly, and the statistical optimal method to speed up the computation. It is very suitable for solving high complexity problems, and quickly yields solutions which converge to the Pareto-optimal set with high precision and uniform distribution. Some complicated multi objective problems are solved by the algorithm and the results show that the algorithm is not only fast but also superior to other MCGAS and MOEAs, such as the currently efficient algorithm SPEA, in terms of the precision, quantity and distribution of solutions.
Application of the complex scaling method in solving three-body Coulomb scattering problem
Lazauskas, R.
2017-03-01
The three-body scattering problem in Coulombic systems is a widespread, yet unresolved problem using the mathematically rigorous methods. In this work this long-term challenge has been undertaken by combining distorted waves and Faddeev–Merkuriev equation formalisms in conjunction with the complex scaling technique to overcome the difficulties related with the boundary conditions. Unlike the common belief, it is demonstrated that the smooth complex scaling method can be applied to solve the three-body Coulomb scattering problem in a wide energy region, including the fully elastic domain and extending to the energies well beyond the atom ionization threshold. A newly developed method is used to study electron scattering on the ground states of hydrogen and positronium atoms as well as a {e}++{{H}}({n}=1)\\rightleftarrows {{p}}+{Ps}({n}=1) reaction. Where available, obtained results are compared with the experimental data and theoretical predictions, proving the accuracy and efficiency of the newly developed method.
A new complex variable element-free Galerkin method for two-dimensional potential problems
Institute of Scientific and Technical Information of China (English)
Cheng Yu-Min; Wang Jian-Fei; Bai Fu-Nong
2012-01-01
In this paper,based on the element-free Galerkin (EFG) method and the improved complex variable moving least-square (ICVMLS) approximation,a new meshless method,which is the improved complex variable element-free Galerkin (ICVEFG) method for two-dimensional potential problems,is presented. In the method,the integral weak form of control equations is employed,and the Lagrange multiplier is used to apply the essential boundary conditions.Then the corresponding formulas of the ICVEFG method for two-dimensional potential problems are obtained.Compared with the complex variable moving least-square (CVMLS) approximation proposed by Cheng,the functional in the ICVMLS approximation has an explicit physical meaning.Furthermore,the ICVEFG method has greater computational precision and efficiency.Three numerical examples are given to show the validity of the proposed method.
The Consensus String Problem and the Complexity of Comparing Hidden Markov Models
DEFF Research Database (Denmark)
Lyngsø, Rune Bang; Pedersen, Christian Nørgaard Storm
2002-01-01
The basic theory of hidden Markov models was developed and applied to problems in speech recognition in the late 1960s, and has since then been applied to numerous problems, e.g. biological sequence analysis. Most applications of hidden Markov models are based on efficient algorithms for computing...... the probability of generating a given string, or computing the most likely path generating a given string. In this paper we consider the problem of computing the most likely string, or consensus string, generated by a given model, and its implications on the complexity of comparing hidden Markov models. We show...... that computing the consensus string, and approximating its probability within any constant factor, is NP-hard, and that the same holds for the closely related labeling problem for class hidden Markov models. Furthermore, we establish the NP-hardness of comparing two hidden Markov models under the L∞- and L1...
Institute of Scientific and Technical Information of China (English)
程玉民; 刘超; 白福浓; 彭妙娟
2015-01-01
In this paper, based on the conjugate of the complex basis function, a new complex variable moving least-squares approximation is discussed. Then using the new approximation to obtain the shape function, an improved complex vari-able element-free Galerkin (ICVEFG) method is presented for two-dimensional (2D) elastoplasticity problems. Compared with the previous complex variable moving least-squares approximation, the new approximation has greater computational precision and efficiency. Using the penalty method to apply the essential boundary conditions, and using the constrained Galerkin weak form of 2D elastoplasticity to obtain the system equations, we obtain the corresponding formulae of the ICVEFG method for 2D elastoplasticity. Three selected numerical examples are presented using the ICVEFG method to show that the ICVEFG method has the advantages such as greater precision and computational efficiency over the conven-tional meshless methods.
Castelvecchi, Davide
2007-01-01
The world's most powerful atom smasher turns on this year. The author foresees some breakthroughts - and more than a few tricky problems: the most likely scenario is that we're going to have a ton of weird stuff to explain. (3 pages)
The lower bound on complexity of parallel branch-and-bound algorithm for subset sum problem
Kolpakov, Roman; Posypkin, Mikhail
2016-10-01
The subset sum problem is a particular case of the Boolean knapsack problem where each item has the price equal to its weight. This problem can be informally stated as searching for most dense packing of a set of items into a box with limited capacity. Recently, coarse-grain parallelization approaches to Branch-and-Bound (B&B) method attracted some attention due to the growing popularity of weakly-connected distributed computing platforms. In this paper we consider one of such approaches for solving the subset sum problem. One of the processors (manager) performs some number of B&B steps on the first stage with generating some subproblems. On the second stage, the generated subproblems are sent to other processors, one subproblem per processor. The processors solve completely the received subproblems, the manager collects all the obtained solutions and chooses the optimal one. For this algorithm we formally define the parallel execution model (frontal scheme of parallelization) and the notion of the frontal scheme complexity. We study the frontal scheme complexity for a series of subset sum problems.
Extending XCS with Cyclic Graphs for Scalability on Complex Boolean Problems.
Iqbal, Muhammad; Browne, Will N; Zhang, Mengjie
2015-09-25
A main research direction in the field of evolutionary machine learning is to develop a scalable classifier system to solve high-dimensional problems. Recently work has begun on autonomously reusing learned building blocks of knowledge to scale from low-dimensional problems to high-dimensional ones. An XCS-based classifier system, known as XCSCFC, has been shown to be scalable, through the addition of expression tree-like code fragments, to a limit beyond standard learning classifier systems. XCSCFC is especially beneficial if the target problem can be divided into a hierarchy of subproblems and each of them is solvable in a bottom-up fashion. However, if the hierarchy of subproblems is too deep, then XCSCFC becomes impractical because of the needed computational time and thus eventually hits a limit in problem size. A limitation in this technique is the lack of a cyclic representation, which is inherent in finite state machines (FSMs). However, the evolution of FSMs is a hard task owing to the combinatorially large number of possible states, connections, and interaction. Usually this requires supervised learning to minimize inappropriate FSMs, which for high-dimensional problems necessitates subsampling or incremental testing. To avoid these constraints, this work introduces a state-machine-based encoding scheme into XCS for the first time, termed XCSSMA. The proposed system has been tested on six complex Boolean problem domains: multiplexer, majority-on, carry, even-parity, count ones, and digital design verification problems. The proposed approach outperforms XCSCFA (an XCS that computes actions) and XCSF (an XCS that computes predictions) in three of the six problem domains, while the performance in others is similar. In addition, XCSSMA evolved, for the first time, compact and human readable general classifiers (i.e., solving any n-bit problems) for the even-parity and carry problem domains, demonstrating its ability to produce scalable solutions using a
DEFF Research Database (Denmark)
Angelsky, O. V.; Gorsky, M. P.; Hanson, Steen Grüner;
2014-01-01
We propose an optical correlation algorithm illustrating a new general method for reconstructing the phase skeleton of complex optical fields from the measured two-dimensional intensity distribution. The core of the algorithm consists in locating the saddle points of the intensity distribution an...... and connecting such points into nets by the lines of intensity gradient that are closely associated with the equi-phase lines of the field. This algorithm provides a new partial solution to the inverse problem in optics commonly referred to as the phase problem....
Institute of Scientific and Technical Information of China (English)
Yang Xiu-Li; Dai Bao-Dong; Zhang Wei-Wei
2012-01-01
Based on the complex variable moving least-square (CVMLS) approximation and a local symmetric weak form,the complex variable meshless local Petrov-Galerkin (CVMLPG) method of solving two-dimensional potential problems is presented in this paper.In the present formulation,the trial function of a two-dimensional problem is formed with a one-dimensional basis function.The number of unknown coefficients in the trial function of the CVMLS approximation is less than that in the trial function of the moving least-square (MLS) approximation.The essential boundary conditions are imposed by the penalty method.The main advantage of this approach over the conventional meshless local PetrovGalerkin (MLPG) method is its computational efficiency.Several numerical examples are presented to illustrate the implementation and performance of the present CVMLPG method.
Solving the three-body Coulomb breakup problem using exterior complex scaling
Energy Technology Data Exchange (ETDEWEB)
McCurdy, C.W.; Baertschy, M.; Rescigno, T.N.
2004-05-17
Electron-impact ionization of the hydrogen atom is the prototypical three-body Coulomb breakup problem in quantum mechanics. The combination of subtle correlation effects and the difficult boundary conditions required to describe two electrons in the continuum have made this one of the outstanding challenges of atomic physics. A complete solution of this problem in the form of a ''reduction to computation'' of all aspects of the physics is given by the application of exterior complex scaling, a modern variant of the mathematical tool of analytic continuation of the electronic coordinates into the complex plane that was used historically to establish the formal analytic properties of the scattering matrix. This review first discusses the essential difficulties of the three-body Coulomb breakup problem in quantum mechanics. It then describes the formal basis of exterior complex scaling of electronic coordinates as well as the details of its numerical implementation using a variety of methods including finite difference, finite elements, discrete variable representations, and B-splines. Given these numerical implementations of exterior complex scaling, the scattering wave function can be generated with arbitrary accuracy on any finite volume in the space of electronic coordinates, but there remains the fundamental problem of extracting the breakup amplitudes from it. Methods are described for evaluating these amplitudes. The question of the volume-dependent overall phase that appears in the formal theory of ionization is resolved. A summary is presented of accurate results that have been obtained for the case of electron-impact ionization of hydrogen as well as a discussion of applications to the double photoionization of helium.
TOPICAL REVIEW: Solving the three-body Coulomb breakup problem using exterior complex scaling
McCurdy, C. W.; Baertschy, M.; Rescigno, T. N.
2004-09-01
Electron-impact ionization of the hydrogen atom is the prototypical three-body Coulomb breakup problem in quantum mechanics. The combination of subtle correlation effects and the difficult boundary conditions required to describe two electrons in the continuum have made this one of the outstanding challenges of atomic physics. A complete solution of this problem in the form of a 'reduction to computation' of all aspects of the physics is given by the application of exterior complex scaling, a modern variant of the mathematical tool of analytic continuation of the electronic coordinates into the complex plane that was used historically to establish the formal analytic properties of the scattering matrix. This review first discusses the essential difficulties of the three-body Coulomb breakup problem in quantum mechanics. It then describes the formal basis of exterior complex scaling of electronic coordinates as well as the details of its numerical implementation using a variety of methods including finite difference, finite elements, discrete variable representations and B-splines. Given these numerical implementations of exterior complex scaling, the scattering wavefunction can be generated with arbitrary accuracy on any finite volume in the space of electronic coordinates, but there remains the fundamental problem of extracting the breakup amplitudes from it. Methods are described for evaluating these amplitudes. The question of the volume-dependent overall phase that appears in the formal theory of ionization is resolved. A summary is presented of accurate results that have been obtained for the case of electron-impact ionization of hydrogen as well as a discussion of applications to the double photoionization of helium.
Migration of levonorgestrel IUS in a patient with complex medical problems: what should be done?
Soleymani Majd, Hooman; El Hamamy, Essam; Chandrasekar, Ramya; Ismail, Lamiese
2009-03-01
Patients with complex medical problems should be counselled about the need for highly effective contraception. As failure resulting in pregnancy, could cause significant morbidity and mortality. The LNG-IUS has gained great popularity and generally has a low side effect profile; however, perforation of the uterus and migration of the device is a potentially serious complication known to be associated with its use. The current accepted management is removal of the device from the abdominal cavity in order to prevent further morbidity. However this is not always a simple matter in patients who have complex medical problems and who are deemed unfit for surgery. Each time the patient comes for renewal of the contraceptive method, clinicians need to reassess the risks and benefits. This is particularly relevant in patients who have complex medical problems where special attention needs to be given, not only to immediate risks but also to long-term ones. Careful individualised counselling and consideration are paramount and perhaps it would have been prudent to discuss vasectomy with this patient and her husband (as the first line of contraception), as this may have avoided the ensuing complications arising from the chosen method.
The Complexity of Checking Consistency of Pedigree Information and Related Problems
Institute of Scientific and Technical Information of China (English)
Luca Aceto; Jens A. Hansen; Anna Ingólfsdóttir; Jacob Johnsen; John Knudsen
2004-01-01
Consistency checking is a fundamental computational problem in genetics. Given a pedigree and information on the genotypes (of some) of the individuals in it, the aim of consistency checking is to determine whether these data are consistent with the classic Mendelian laws of inheritance. This problem arose originally from the geneticists' need to filter their input data from erroneous information, and is well motivated from both a biological and a sociological viewpoint. This paper shows that consistency checking is NP-complete, even with focus on a single gene and in the presence of three alleles. Several other results on the computational complexity of problems from genetics that are related to consistency checking are also offered. In particular, it is shown that checking the consistency of pedigrees over two alleles, and of pedigrees without loops, can be done in polynomial time.
On the Fractality of Complex Networks: Covering Problem, Algorithms and Ahlfors Regularity
Wang, Lihong; Wang, Qin; Xi, Lifeng; Chen, Jin; Wang, Songjing; Bao, Liulu; Yu, Zhouyu; Zhao, Luming
2017-01-01
In this paper, we revisit the fractality of complex network by investigating three dimensions with respect to minimum box-covering, minimum ball-covering and average volume of balls. The first two dimensions are calculated through the minimum box-covering problem and minimum ball-covering problem. For minimum ball-covering problem, we prove its NP-completeness and propose several heuristic algorithms on its feasible solution, and we also compare the performance of these algorithms. For the third dimension, we introduce the random ball-volume algorithm. We introduce the notion of Ahlfors regularity of networks and prove that above three dimensions are the same if networks are Ahlfors regular. We also provide a class of networks satisfying Ahlfors regularity. PMID:28128289
Molecular computing towards a novel computing architecture for complex problem solving
Chang, Weng-Long
2014-01-01
This textbook introduces a concise approach to the design of molecular algorithms for students or researchers who are interested in dealing with complex problems. Through numerous examples and exercises, you will understand the main difference of molecular circuits and traditional digital circuits to manipulate the same problem and you will also learn how to design a molecular algorithm of solving any a problem from start to finish. The book starts with an introduction to computational aspects of digital computers and molecular computing, data representation of molecular computing, molecular operations of molecular computing and number representation of molecular computing, and provides many molecular algorithm to construct the parity generator and the parity checker of error-detection codes on digital communication, to encode integers of different formats, single precision and double precision of floating-point numbers, to implement addition and subtraction of unsigned integers, to construct logic operations...
Understanding the problem with logarithmic singularities in the complex Langevin method
Nishimura, Jun
2015-01-01
In recent years, there has been remarkable progress in theoretical justification of the complex Langevin method, which is a promising method for evading the sign problem in the path integral with a complex weight. There still remains, however, an issue concerning occasional failure of this method in the case where the action involves logarithmic singularities such as the one appearing from the fermion determinant in finite density QCD. In this talk, we point out that this failure is due to the breakdown of the relation between the complex weight which satisfies the Fokker-Planck equation and the probability distribution generated by the stochastic process. In fact, this kind of failure can occur in general when the stochastic process involves a singular drift term. We show, however, in simple examples, that there exists a parameter region in which the method works although the standard reweighting method is hardly applicable.
An improved complex variable element-free Galerkin method for two-dimensional elasticity problems
Institute of Scientific and Technical Information of China (English)
Bai Fu-Nong; Li Dong-Ming; Wang Jian-Fei; Cheng Yu-Min
2012-01-01
In this paper,the improved complex variable moving least-squares (ICVMLS) approximation is presented.The ICVMLS approximation has an explicit physics meaning.Compared with the complex variable moving least-squares (CVMLS) approximations presented by Cheng and Ren,the ICVMLS approximation has a great computational precision and efficiency. Based on the element-free Galerkin (EFG) method and the ICVMLS approximation,the improved complex variable element-free Galerkin (ICVEFG) method is presented for two-dimensional elasticity problems,and the corresponding formulae are obtained.Compared with the conventional EFG method,the ICVEFG method has a great computational accuracy and efficiency.For the purpose of demonstration,three selected numerical examples are solved using the ICVEFG method.
How to solve complex problems in foundry plants - future of casting simulation -
Ohnaka, I.
2015-06-01
Although the computer simulation of casting has progressed dramatically over the last decades, there are still many challenges and problems. This paper discusses how to solve complex engineering problems in foundry plants and what we should do in the future, in particular, for casting simulation. First, problem solving procedures including application of computer simulation are demonstrated and various difficulties are pointed-out exemplifying mainly porosity defects in sand castings of spheroidal graphite cast irons. Next, looking back conventional scientific and engineering research to understand casting phenomena, challenges and problems are discussed from problem solving view point, followed by discussion on the issues we should challenge such as how to integrate huge amount of dispersed knowledge in various disciplines, differentiation of science-oriented and engineering-oriented models, professional ethics, how to handle fluctuating materials, initial and boundary conditions, error accumulation, simulation codes as black-box, etc. Finally some suggestions are made on how to challenge the issues such as promotion of research on the simulation based on the science- oriented model and publication of reliable data of casting phenomena in complicated-shaped castings including reconsideration of the evaluation system.
Editorial: Biotechnology Journal brings more than biotechnology.
Jungbauer, Alois; Lee, Sang Yup
2015-09-01
Biotechnology Journal always brings the state-of-the-art biotechnologies to our readers. Different from other topical issues, this issue of Biotechnology Journal is complied with a series of exiting reviews and research articles from spontaneous submissions, again, addressing society's actual problems and needs. The progress is a real testimony how biotechnology contributes to achievements in healthcare, better utilization of resources, and a bio-based economy.
Understanding and quantifying cognitive complexity level in mathematical problem solving items
Directory of Open Access Journals (Sweden)
SUSAN E. EMBRETSON
2008-09-01
Full Text Available The linear logistic test model (LLTM; Fischer, 1973 has been applied to a wide variety of new tests. When the LLTM application involves item complexity variables that are both theoretically interesting and empirically supported, several advantages can result. These advantages include elaborating construct validity at the item level, defining variables for test design, predicting parameters of new items, item banking by sources of complexity and providing a basis for item design and item generation. However, despite the many advantages of applying LLTM to test items, it has been applied less often to understand the sources of complexity for large-scale operational test items. Instead, previously calibrated item parameters are modeled using regression techniques because raw item response data often cannot be made available. In the current study, both LLTM and regression modeling are applied to mathematical problem solving items from a widely used test. The findings from the two methods are compared and contrasted for their implications for continued development of ability and achievement tests based on mathematical problem solving items.
Bringing Geoethics into Society
Di Capua, Giuseppe; Bobrowsky, Peter; Kieffer, Susan; Peppoloni, Silvia; Tinti, Stefano
2015-04-01
The responsibility and role of the scientific community in the proper exploitation of natural resources, in the defense against natural hazards and in building geoeducational strategies for the population are key themes of Geoethics. But, what is the awareness among Geoscientists about the importance of an ethical debate within Earth Sciences? With the goal to increase this awareness, in 2012 the IAPG - International Association for Promoting Geoethics was founded (http://www.iapg.geoethics.org). The IAPG aims to join forces of geoscientists all over the world, by creating an international, multidisciplinary and scientific platform for discussing on ethical problems and dilemmas in Earth Sciences, for promoting Geoethics themes through scientific publications and conferences, for strengthening the research base on Geoethics, for focusing on case-studies to be taken as models for the development of effective and operative strategies. The IAPG has obtained the status of affiliated organization by the International Union of Geological Sciences (IUGS), it is among the collaborative organizations of the IUGS - Task Group on Global Geoscience Professionalism (TGGGP), and it has been recognized as an International Associate Organization of the American Geosciences Institute (AGI). The IAPG network is growing fast and currently it is going to reach 500 members in more than 75 countries in 5 continents. The IAPG is working to offer its contribution in building a framework of values for a new model of development, more respectful towards the Geosphere. After 2 years of successful results and numerous ongoing activities, IAPG appears to be on the right way in promoting new ideas to research and practice geosciences. This work aims to give an overview on the IAPG activities, to illustrate the IAPG impact on public through web-statistics, to present publications, events and other initiatives on Geoethics carried out by its members.
Energy Technology Data Exchange (ETDEWEB)
H. B. HUNT; D. J. ROSENKRANTS; ET AL
2001-03-01
We identify several simple but powerful concepts, techniques, and results; and we use them to characterize the complexities of a number of basic problems II, that arise in the analysis and verification of the following models M of communicating automata and discrete dynamical systems: systems of communicating automata including both finite and infinite cellular automata, transition systems, discrete dynamical systems, and succinctly-specified finite automata. These concepts, techniques, and results are centered on the following: (i) reductions Of STATE-REACHABILITY problems, especially for very simple systems of communicating copies of a single simple finite automaton, (ii) reductions of generalized CNF satisfiability problems [Sc78], especially to very simple communicating systems of copies of a few basic acyclic finite sequential machines, and (iii) reductions of the EMPTINESS and EMPTINESS-OF-INTERSECTION problems, for several kinds of regular set descriptors. For systems of communicating automata and transition systems, the problems studied include: all equivalence relations and simulation preorders in the Linear-time/Branching-time hierarchies of equivalence relations and simulation preorders of [vG90, vG93], both without and with the hiding abstraction. For discrete dynamical systems, the problems studied include the INITIAL and BOUNDARY VALUE PROBLEMS (denoted IVPs and BVPS, respectively), for nonlinear difference equations over many different algebraic structures, e.g. all unitary rings, all finite unitary semirings, and all lattices. For succinctly-specified finite automata, the problems studied also include the several problems studied in [AY98], e.g. the EMPTINESS, EMPTINESS-OF-INTERSECTION, EQUIVALENCE and CONTAINMENT problems. The concepts, techniques, and results presented unify and significantly extend many of the known results in the literature, e.g. [Wo86, Gu89, BPT91, GM92, Ra92, HT94, SH+96, AY98, AKY99, RH93, SM73, Hu73, HRS76, HR78], for
Energy Technology Data Exchange (ETDEWEB)
Hunt, H. B. (Harry B.); Rosenkrantz, D. J. (Daniel J.); Barrett, C. L. (Christopher L.); Marathe, M. V. (Madhav V.); Ravi, S. S. (Sekharipuram S.)
2001-01-01
We identify several simple but powerful concepts, techniques, and results; and we use them to characterize the complexities of a number of basic problems II, that arise in the analysis and verification of the following models M of communicating automata and discrete dynamical systems: systems of communicating automata including both finite and infinite cellular automata, transition systems, discrete dynamical systems, and succinctly-specified finite automata. These concepts, techniques, and results are centered on the following: (1) reductions Of STATE-REACHABILITY problems, especially for very simple systems of communicating copies of a single simple finite automaton, (2) reductions of generalized CNF satisfiability problems [Sc78], especially to very simple communicating systems of copies of a few basic acyclic finite sequential machines, and (3) reductions of the EMPTINESS and EMPTINESS-OF-INTERSECTION problems, for several kinds of regular set descriptors. For systems of communicating automata and transition systems, the problems studied include: all equivalence relations and simulation preorders in the Linear-time/Branching-time hierarchies of equivalence relations and simulation preorders of [vG90, vG93], both without and with the hiding abstraction. For discrete dynamical systems, the problems studied include the INITIAL and BOUNDARY VALUE PROBLEMS (denoted IVPs and BVPs, respectively), for nonlinear difference equations over many different algebraic structures, e.g. all unitary rings, all finite unitary semirings, and all lattices. For succinctly specified finite automata, the problems studied also include the several problems studied in [AY98], e.g. the EMPTINESS, EMPTINESS-OF-INTERSECTION, EQUIVALENCE and CONTAINMENT problems. The concepts, techniques, and results presented unify and significantly extend many of the known results in the literature, e.g. [Wo86, Gu89, BPT91, GM92, Ra92, HT94, SH+96, AY98, AKY99, RH93, SM73, Hu73, HRS76, HR78], for
Bogard, Treavor; Liu, Min; Chiang, Yueh-hui Vanessa
2013-01-01
This multiple-case study examined how advanced learners solved a complex problem, focusing on how their frequency and application of cognitive processes contributed to differences in performance outcomes, and developing a mental model of a problem. Fifteen graduate students with backgrounds related to the problem context participated in the study.…
Two-Level Solutions to Exponentially Complex Problems in Glass Science
DEFF Research Database (Denmark)
Mauro, John C.; Smedskjær, Morten Mattrup
Glass poses an especially challenging problem for physicists. The key to making progress in theoretical glass science is to extract the key physics governing properties of practical interest. In this spirit, we discuss several two-level solutions to exponentially complex problems in glass science....... Topological constraint theory, originally developed by J.C. Phillips, is based on a two-level description of rigid and floppy modes in a glass network and can be used to derive quantitatively accurate and analytically solvable models for a variety of macroscopic properties. The temperature dependence...... of the floppy mode density is used to derive the new MYEGA model of supercooled liquid viscosity, which offers improved descriptions for the temperature and composition dependence of relaxation time. The relaxation behavior of the glassy state can be further elucidated using a two-level energy landscape...
On complex roots of an equation arising in the oblique derivative problem
Kostin, A. B.; Sherstyukov, V. B.
2017-01-01
The paper is concerned with the eigenvalue problem for the Laplace operator in a disc under the condition that the oblique derivative vanishes on the disc boundary. In a famous article by V.A. Il’in and E.I. Moiseev (Differential equations, 1994) it was found, in particular, that the root of any equation of the form with the Bessel function Jn (μ) determines the eigenvalue λ = μ 2 of the problem. In our work we correct the information about the location of eigenvalues. It is specified explicit view of the corner, containing all the eigenvalues. It is shown that all the nonzero roots of the equation are simple and given a refined description of the set of their localization on the complex plane. To prove these facts we use the partial differential equations methods and also methods of entire functions theory.
A Hybrid Genetic Algorithm for Vehicle Routing Problem with Complex Constraints
Institute of Scientific and Technical Information of China (English)
CHEN Yan; LU Jun; LI Zeng-zhi
2006-01-01
Most research on the Vehicle Routing Problem (VRP) is focused on standard conditions, which is not suitable for specific cases. A Hybrid Genetic Algorithm is proposed to solve a Vehicle Routing Problem (VRP) with complex side constraints. A novel coding method is designed especially for side constraints. A greedy algorithm combined with a random algorithm is introduced to enable the diversity of the initial population, as well as a local optimization algorithm employed to improve the searching efficiency. In order to evaluate the performance, this mechanism has been implemented in an oil distribution center, the experimental and executing results show that the near global optimal solution can be easily and quickly obtained by this method, and the solution is definitely satisfactory in the VRP application.
Barron-Romero, Carlos
2011-01-01
This paper presents the differences between two NP problems. It focuses in the Euclidian 2 Dimension Travelling Salesman Problems and General Assign Problems. The main results are the triangle reduction to verify the solution in polynomial time for the former and for the later the solution to the Noted Conjecture of the NP-Class, NP is not P.
Complex history as a source of planning problems: Old Belgrade fairground
Directory of Open Access Journals (Sweden)
Vukotić-Lazar Marta
2006-01-01
Full Text Available The Old Belgrade Fairground complex is the large area in the center of Belgrade that is completely isolated from other parts of Belgrade: it is one of the most devastated city areas, populated by poor inhabitants, often by those from the marginal groups, burdened with tragic history and it represents one of hardest problems for planners to solve. It is situated on the left bank of the Sava River between two bridges and downtown New Belgrade. Opposite to it, the Sava Amphitheatre slopes down the Belgrade Ridge towards the river. The complex was built in the thirties of the 20th century across the River Sava in the area that was an unpopulated swamp - Belgrade was situated on the right Sava bank. It was meant to be modern extension of oriental city, which could represent the western tendencies of the young state (Kingdom of Yugoslavia and its capital. Modern and monumental complex of exhibition and commercial pavilions was built, and started its life with national and international fairs and exhibitions. World War 2 changed its destiny: German occupation forces transformed the complex into the concentration camp, where thousands of people were tortured and killed. After the war, new republican government, both communist and antifascist, had double frustration regarding this space: it’s tragic (during the War and "capitalist" (before the War past, so complex that was absolutely ignored in the period of the postwar renewal, and the result is described at the beginning of this text. This paper discusses the possibility to conciliate historical roles of the complex, and to realize it’s potentials in the modern world. Facts of the complex’s history are presented in the first part of the paper. Further on, these facts are analyzed in the context of contemporary city development of Belgrade in particular but globally, too.. Finally, some guidelines for crossing the gap between this area and the rest of the city are presented in the third part of
Energy Technology Data Exchange (ETDEWEB)
Wiek, Arnim, E-mail: arnim.wiek@asu.edu; Foley, Rider W. [Arizona State University, School of Sustainability (United States); Guston, David H. [Arizona State University, Center for Nanotechnology in Society, Consortium for Science, Policy and Outcomes (United States)
2012-09-15
Nanotechnology is widely associated with the promise of positively contributing to sustainability. However, this view often focuses on end-of-pipe applications, for instance, for water purification or energy efficiency, and relies on a narrow concept of sustainability. Approaching sustainability problems and solution options from a comprehensive and systemic perspective instead may yield quite different conclusions about the contribution of nanotechnology to sustainability. This study conceptualizes sustainability problems as complex constellations with several potential intervention points and amenable to different solution options. The study presents results from interdisciplinary workshops and literature reviews that appraise the contribution of the selected nanotechnologies to mitigate such problems. The study focuses exemplarily on the urban context to make the appraisals tangible and relevant. The solution potential of nanotechnology is explored not only for well-known urban sustainability problems such as water contamination and energy use but also for less obvious ones such as childhood obesity. Results indicate not only potentials but also limitations of nanotechnology's contribution to sustainability and can inform anticipatory governance of nanotechnology in general, and in the urban context in particular.
Energy Technology Data Exchange (ETDEWEB)
Tahvili, Sahar [Mälardalen University (Sweden); Österberg, Jonas; Silvestrov, Sergei [Division of Applied Mathematics, Mälardalen University (Sweden); Biteus, Jonas [Scania CV (Sweden)
2014-12-10
One of the most important factors in the operations of many cooperations today is to maximize profit and one important tool to that effect is the optimization of maintenance activities. Maintenance activities is at the largest level divided into two major areas, corrective maintenance (CM) and preventive maintenance (PM). When optimizing maintenance activities, by a maintenance plan or policy, we seek to find the best activities to perform at each point in time, be it PM or CM. We explore the use of stochastic simulation, genetic algorithms and other tools for solving complex maintenance planning optimization problems in terms of a suggested framework model based on discrete event simulation.
Bermeo Varon, L. A.; Orlande, H. R. B.; Eliçabe, G. E.
2016-09-01
The particle filter methods have been widely used to solve inverse problems with sequential Bayesian inference in dynamic models, simultaneously estimating sequential state variables and fixed model parameters. This methods are an approximation of sequences of probability distributions of interest, that using a large set of random samples, with presence uncertainties in the model, measurements and parameters. In this paper the main focus is the solution combined parameters and state estimation in the radiofrequency hyperthermia with nanoparticles in a complex domain. This domain contains different tissues like muscle, pancreas, lungs, small intestine and a tumor which is loaded iron oxide nanoparticles. The results indicated that excellent agreements between estimated and exact value are obtained.
Perfect absorption in Schrödinger-like problems using non-equidistant complex grids
Weinmüller, Markus; Weinmüller, Michael; Rohland, Jonathan; Scrinzi, Armin
2017-03-01
Two non-equidistant grid implementations of infinite range exterior complex scaling are introduced that allow for perfect absorption in the time dependent Schrödinger equation. Finite element discrete variables discretizations provide as efficient absorption as the corresponding finite elements discretizations. This finding is at variance with results reported in literature [L. Tao et al., Phys. Rev. A 48, 063419 (2009)]. For finite differences, a new class of generalized Q-point schemes for non-equidistant grids is derived. Convergence of absorption is exponential ∼ Δx Q - 1 and numerically robust. Local relative errors ≲10-9 are achieved in a standard problem of strong-field ionization.
McDonald, Ruth
2014-10-01
There is a trend in health systems around the world to place great emphasis on and faith in improving 'leadership'. Leadership has been defined in many ways and the elitist implications of traditional notions of leadership sit uncomfortably with modern healthcare organisations. The concept of distributed leadership incorporates inclusivity, collectiveness and collaboration, with the result that, to some extent, all staff, not just those in senior management roles, are viewed as leaders. Leadership development programmes are intended to equip individuals to improve leadership skills, but we know little about their effectiveness. Furthermore, the content of these programmes varies widely and the fact that many lack a sense of how they fit with individual or organisational goals raises questions about how they are intended to achieve their aims. It is important to avoid simplistic assumptions about the ability of improved leadership to solve complex problems. It is also important to evaluate leadership development programmes in ways that go beyond descriptive accounts.
A topological approach to the problem of emergence in complex systems
Pascual-García, Alberto
2016-01-01
Emergent patterns in complex systems are related to many intriguing phenomena in modern science and philosophy. Several conceptions such as weak, strong and robust emergence have been proposed to emphasize different epistemological and ontological aspects of the problem. One of the most important concerns is whether emergence is an intrinsic property of the reality we observe, or it is rather a consequence of epistemological limitations. To elucidate this question, we propose a novel approximation through constructive topology, a framework that allow us to map the space of observed objects (ontology) with the knowledge subject conceptual apparatus (epistemology). Focusing in a particular type of emergent processes, namely those accessible through experiments and from which we have still no clue on the mechanistic processes yielding its formation, we analyse how a knowledge subject would build a conceptual explanatory framework. Working on these systems, we identify concept disjunction as a critical logical op...
Addressing complex healthcare problems in diverse settings: insights from activity theory.
Greig, Gail; Entwistle, Vikki A; Beech, Nic
2012-02-01
In the U.K., approaches to policy implementation, service improvement and quality assurance treat policy, management and clinical care as separate, hierarchical domains. They are often based on the central knowledge transfer (KT) theory idea that best practice solutions to complex problems can be identified and 'rolled out' across organisations. When the designated 'best practice' is not implemented, this is interpreted as local--particularly management--failure. Remedial actions include reiterating policy aims and tightening performance management of solution implementation, frequently to no avail. We propose activity theory (AT) as an alternative approach to identifying and understanding the challenges of addressing complex healthcare problems across diverse settings. AT challenges the KT conceptual separations between levels of policy, management and clinical care. It does not regard knowledge and practice as separable, and does not understand them in the commodified way that has typified some versions of KT theory. Instead, AT focuses on "objects of activity" which can be contested. It sees new practice as emerging from contradiction and understands knowledge and practice as fundamentally entwined, not separate. From an AT perspective, there can be no single best practice. The contributions of AT are that it enables us to understand the dynamics of knowledge-practice in activities rather than between levels. It shows how efforts to reduce variation from best practice may paradoxically remove a key source of practice improvement. After explaining the principles of AT we illustrate its explanatory potential through an ethnographic study of primary healthcare teams responding to a policy aim of reducing inappropriate hospital admissions of older people by the 'best practice' of rapid response teams.
Angeli, Charoula; Valanides, Nicos
2013-01-01
The present study investigated the problem-solving performance of 101 university students and their interactions with a computer modeling tool in order to solve a complex problem. Based on their performance on the hidden figures test, students were assigned to three groups of field-dependent (FD), field-mixed (FM), and field-independent (FI)…
Winkel, Brian
2008-01-01
A complex technology-based problem in visualization and computation for students in calculus is presented. Strategies are shown for its solution and the opportunities for students to put together sequences of concepts and skills to build for success are highlighted. The problem itself involves placing an object under water in order to actually see…
Eseryel, Deniz; Law, Victor; Ifenthaler, Dirk; Ge, Xun; Miller, Raymond
2014-01-01
Digital game-based learning, especially massively multiplayer online games, has been touted for its potential to promote student motivation and complex problem-solving competency development. However, current evidence is limited to anecdotal studies. The purpose of this empirical investigation is to examine the complex interplay between…
Buehler, Deborah M.; Versteegh, Maaike A.; Matson, Kevin D.; Tieleman, Irene
2011-01-01
The immune system is a complex collection of interrelated and overlapping solutions to the problem of disease. To deal with this complexity, researchers have devised multiple ways to measure immune function and to analyze the resulting data. In this way both organisms and researchers employ many tac
Buehler, D.M.; Versteegh, M.A.; Matson, K.D.; Tieleman, B.I.
2011-01-01
The immune system is a complex collection of interrelated and overlapping solutions to the problem of disease. To deal with this complexity, researchers have devised multiple ways to measure immune function and to analyze the resulting data. In this way both organisms and researchers employ many tac
Eseryel, Deniz; Law, Victor; Ifenthaler, Dirk; Ge, Xun; Miller, Raymond
2014-01-01
Digital game-based learning, especially massively multiplayer online games, has been touted for its potential to promote student motivation and complex problem-solving competency development. However, current evidence is limited to anecdotal studies. The purpose of this empirical investigation is to examine the complex interplay between learners'…
Bringing Secrecy into the Open
DEFF Research Database (Denmark)
Costas, Jana; Grey, Christopher
2014-01-01
This paper brings into focus the concept of organizational secrecy, defined as the ongoing formal and informal social processes of intentional concealment of information from actors by actors in organizations. It is argued that existing literature on the topic is fragmented and predominantly...
Bringing reality into the classroom
Heck, A.
2009-01-01
Technology offers ample opportunities to bring reality into the classroom. Students and teachers nowadays have many tools to work in an authentic way with real data in mathematics and science education. However, much research and development are still needed to create a consistent learning trajector
Directory of Open Access Journals (Sweden)
Yekini Shehu
2010-01-01
real Banach space which is also uniformly smooth using the properties of generalized f-projection operator. Using this result, we discuss strong convergence theorem concerning general H-monotone mappings and system of generalized mixed equilibrium problems in Banach spaces. Our results extend many known recent results in the literature.
On Bringing Industry English Teaching into College English Course
Institute of Scientific and Technical Information of China (English)
魏圆圆
2016-01-01
With the development of global economy, it’s becoming increasingly important to bring industry English into College English Course. But there are still many problems about industry English teaching in most colleges. This paper will analyze these problems and put forward effective measures to promote industry English teaching.
Pak, Chan-gi; Lung, Shu
2009-01-01
Modern airplane design is a multidisciplinary task which combines several disciplines such as structures, aerodynamics, flight controls, and sometimes heat transfer. Historically, analytical and experimental investigations concerning the interaction of the elastic airframe with aerodynamic and in retia loads have been conducted during the design phase to determine the existence of aeroelastic instabilities, so called flutter .With the advent and increased usage of flight control systems, there is also a likelihood of instabilities caused by the interaction of the flight control system and the aeroelastic response of the airplane, known as aeroservoelastic instabilities. An in -house code MPASES (Ref. 1), modified from PASES (Ref. 2), is a general purpose digital computer program for the analysis of the closed-loop stability problem. This program used subroutines given in the International Mathematical and Statistical Library (IMSL) (Ref. 3) to compute all of the real and/or complex conjugate pairs of eigenvalues of the Hessenberg matrix. For high fidelity configuration, these aeroelastic system matrices are large and compute all eigenvalues will be time consuming. A subspace iteration method (Ref. 4) for complex eigenvalues problems with nonsymmetric matrices has been formulated and incorporated into the modified program for aeroservoelastic stability (MPASES code). Subspace iteration method only solve for the lowest p eigenvalues and corresponding eigenvectors for aeroelastic and aeroservoelastic analysis. In general, the selection of p is ranging from 10 for wing flutter analysis to 50 for an entire aircraft flutter analysis. The application of this newly incorporated code is an experiment known as the Aerostructures Test Wing (ATW) which was designed by the National Aeronautic and Space Administration (NASA) Dryden Flight Research Center, Edwards, California to research aeroelastic instabilities. Specifically, this experiment was used to study an instability
Efstratiadis, Andreas; Tsoukalas, Ioannis; Kossieris, Panayiotis; Karavokiros, George; Christofides, Antonis; Siskos, Alexandros; Mamassis, Nikos; Koutsoyiannis, Demetris
2015-04-01
Modelling of large-scale hybrid renewable energy systems (HRES) is a challenging task, for which several open computational issues exist. HRES comprise typical components of hydrosystems (reservoirs, boreholes, conveyance networks, hydropower stations, pumps, water demand nodes, etc.), which are dynamically linked with renewables (e.g., wind turbines, solar parks) and energy demand nodes. In such systems, apart from the well-known shortcomings of water resources modelling (nonlinear dynamics, unknown future inflows, large number of variables and constraints, conflicting criteria, etc.), additional complexities and uncertainties arise due to the introduction of energy components and associated fluxes. A major difficulty is the need for coupling two different temporal scales, given that in hydrosystem modeling, monthly simulation steps are typically adopted, yet for a faithful representation of the energy balance (i.e. energy production vs. demand) a much finer resolution (e.g. hourly) is required. Another drawback is the increase of control variables, constraints and objectives, due to the simultaneous modelling of the two parallel fluxes (i.e. water and energy) and their interactions. Finally, since the driving hydrometeorological processes of the integrated system are inherently uncertain, it is often essential to use synthetically generated input time series of large length, in order to assess the system performance in terms of reliability and risk, with satisfactory accuracy. To address these issues, we propose an effective and efficient modeling framework, key objectives of which are: (a) the substantial reduction of control variables, through parsimonious yet consistent parameterizations; (b) the substantial decrease of computational burden of simulation, by linearizing the combined water and energy allocation problem of each individual time step, and solve each local sub-problem through very fast linear network programming algorithms, and (c) the substantial
Managing the Complexity of Design Problems through Studio-Based Learning
Cennamo, Katherine; Brandt, Carol; Scott, Brigitte; Douglas, Sarah; McGrath, Margarita; Reimer, Yolanda; Vernon, Mitzi
2011-01-01
The ill-structured nature of design problems makes them particularly challenging for problem-based learning. Studio-based learning (SBL), however, has much in common with problem-based learning and indeed has a long history of use in teaching students to solve design problems. The purpose of this ethnographic study of an industrial design class,…
Directory of Open Access Journals (Sweden)
Vladimir V. Kozoderov
1998-01-01
Full Text Available Developing the general statements of the proposed global change theory, outlined in Part 1 of the publication, Kolmogorov's probability space is used to study properties of information measures (unconditional, joint and conditional entropies, information divergence, mutual information, etc.. Sets of elementary events, the specified algebra of their sub-sets and probability measures for the algebra are composite parts of the space. The information measures are analyzed using the mathematical expectance operator and the adequacy between an additive function of sets and their equivalents in the form of the measures. As a result, explanations are given to multispectral satellite imagery visualization procedures using Markov's chains of random variables represented by pixels of the imagery. The proposed formalism of the information measures application enables to describe the natural targets complexity by syntactically governing probabilities. Asserted as that of signal/noise ratios finding for anomalies of natural processes, the predictability problem is solved by analyses of temporal data sets of related measurements for key regions and their background within contextually coherent structures of natural targets and between particular boundaries of the structures.
World, We Have Problems: Simulation for Large Complex, Risky Projects, and Events
Elfrey, Priscilla
2010-01-01
Prior to a spacewalk during the NASA STS/129 mission in November 2009, Columbia Broadcasting System (CBS) correspondent William Harwood reported astronauts, "were awakened again", as they had been the day previously. Fearing something not properly connected was causing a leak, the crew, both on the ground and in space, stopped and checked everything. The alarm proved false. The crew did complete its work ahead of schedule, but the incident reminds us that correctly connecting hundreds and thousands of entities, subsystems and systems, finding leaks, loosening stuck valves, and adding replacements to very large complex systems over time does not occur magically. Everywhere major projects present similar pressures. Lives are at - risk. Responsibility is heavy. Large natural and human-created disasters introduce parallel difficulties as people work across boundaries their countries, disciplines, languages, and cultures with known immediate dangers as well as the unexpected. NASA has long accepted that when humans have to go where humans cannot go that simulation is the sole solution. The Agency uses simulation to achieve consensus, reduce ambiguity and uncertainty, understand problems, make decisions, support design, do planning and troubleshooting, as well as for operations, training, testing, and evaluation. Simulation is at the heart of all such complex systems, products, projects, programs, and events. Difficult, hazardous short and, especially, long-term activities have a persistent need for simulation from the first insight into a possibly workable idea or answer until the final report perhaps beyond our lifetime is put in the archive. With simulation we create a common mental model, try-out breakdowns of machinery or teamwork, and find opportunity for improvement. Lifecycle simulation proves to be increasingly important as risks and consequences intensify. Across the world, disasters are increasing. We anticipate more of them, as the results of global warming
Institute of Scientific and Technical Information of China (English)
Zhenhan TU; Zhonghua WANG
2013-01-01
This paper proves some uniqueness theorems for meromorphic mappings in several complex variables into the complex projective space PN(C) with truncated multiplicities,and our results improve some earlier work.
Innovative development problems of private sector of engineering and defense industrial complexes
Directory of Open Access Journals (Sweden)
A. V. Lugovtsov
2010-09-01
Full Text Available The innovation processes in non-governmental sector of machine building complex and defense industry complex of the Russian Federation are analyzed in this article. Also the recommendations for development are given.
USING OF COMPLEX HARMONIOUS SIGNALS IN PROBLEMS OF ACOUSTIC SPECTROMETRY OF POLYMERS
Directory of Open Access Journals (Sweden)
V. K. Bitiukov
2014-01-01
Full Text Available Summary. In article features of definition of acoustic properties of polymers with application of ultrasonic fluctuations are considered. The opportunity of definition with single method of such parameters of quality as a relaxation spectra of polymer and function of molecular-mass distribution in a solution that results in increase in time of carrying out of measurements is shown. For reduction of time, may use narrowing of a range of frequencies of the ultrasonic fluctuations rendered on the measured sample, or increase the step of quantization of a registered signal with the oscillograph. Thus both variants result in reduction in reliability of the received information because of a possible extends for limits of an effective frequency range or loss of a high-frequency component of a registered signal at increase in a step of quantization. For the decision of the listed problems it is offered to use the complex harmonious signal being superposition of several signals. Frequency is necessary for choosing proceeding from sensitivity of each determined polymer parameter of quality. On concrete examples it is shown, that sensitivity of such parameters of quality as strength and viscosity on Mooney essentially depends on frequency. For initial research, in a case when properties of a material beforehand are not known and it is necessary to reveal effective ranges of frequencies, for each determined property of a material, it is offered to use a signal such as «white noise» which will allow to reveal ranges of frequencies with the greatest sensitivity each measured parameter of quality. That, it is in turn connected to uniform distribution of spectral making frequencies on all possible frequency range. Necessity for definition of an effective range of time of registration and a step of quantization for a kind of limitation of technical opportunities of means of registration of electric signals (oscillographs is shown.
Atrial fibrillation management in older heart failure patients: a complex clinical problem
Directory of Open Access Journals (Sweden)
Stefano Tolone
2016-09-01
Full Text Available Background Atrial fibrillation (AF and heart failure (HF, two problems of growing prevalence as a consequence of the ageing population, are associated with high morbidity, mortality, and healthcare costs. AF and HF also share common risk factors and pathophysiologic processes such as hypertension, diabetes mellitus, ischemic heart disease, and valvular heart disease often occur together. Although elderly patients with both HF and AF are affected by worse symptoms and poorer prognosis, there is a paucity of data on appropriate management of these patients. Methods PubMed was searched for studies on AF and older patients using the terms atrial fibrillation, elderly, heart failure, cognitive impairment, frailty, stroke, and anticoagulants. Results The clinical picture of HF patients with AF is complex and heterogeneous with a higher prevalence of frailty, cognitive impairment, and disability. Because of the association of mental and physical impairment to non-administration of oral anticoagulants (OACs, screening for these simple variables in clinical practice may allow better strategies for intervention in this high-risk population. Since novel direct OACs (NOACs have a more favorable risk-benefit profile, they may be preferable to vitamin K antagonists (VKAs in many frail elderly patients, especially those at higher risk of falls. Moreover, NOACs are simple to administer and monitor and may be associated with better adherence and safety in patients with cognitive deficits and mobility impairments. Conclusions Large multicenter longitudinal studies are needed to examine the effects of VKAs and NOACs on long-term cognitive function and frailty; future studies should include geriatric conditions.
Computational complexity of some maximum average weight problems with precedence constraints
Faigle, Ulrich; Kern, Walter
1994-01-01
Maximum average weight ideal problems in ordered sets arise from modeling variants of the investment problem and, in particular, learning problems in the context of concepts with tree-structured attributes in artificial intelligence. Similarly, trying to construct tests with high reliability leads t
Untangling the Complex Needs of People Experiencing Gambling Problems and Homelessness
Holdsworth, Louise; Tiyce, Margaret
2013-01-01
People with gambling problems are now recognised among those at increased risk of homelessness, and the link between housing and gambling problems has been identified as an area requiring further research. This paper discusses the findings of a qualitative study that explored the relationship between gambling problems and homelessness. Interviews…
Computer Security Team
2013-01-01
Have you ever heard of “BYOD”? No, it is not a pop band. Try again. It is short for “Bring Your Own Device” (the French use “AVEC” - “Apporter Votre Equipement personnel de Communication”) and describes an option long since offered at CERN: the possibility to bring along your personal laptop, smartphone or PDA, use it on CERN premises and connect it to the CERN office network. But hold on. As practical as it is, there is also a dark side. The primary advantage, of course, is having a digital work environment tuned to your needs and preferences. It allows you to continue working at home. Similarly, you always have your music, address books and bookmarks with you. However, as valuable as this is, it is also a responsibility. Laptop theft is happening - outside CERN but also on site. In France, 30% of stolen laptops were stolen out of cars or homes, and 10% during travel. At CERN, on average one ...
Reeve, J.; Blakeman, T.; Freeman, G.K.; Green, L.A.; James, P.A.; Lucassen, P.; Martin, C.M.; Sturmberg, J.P.; Weel, C. van
2013-01-01
BACKGROUND: A growing proportion of people are living with long term conditions. The majority have more than one. Dealing with multi-morbidity is a complex problem for health systems: for those designing and implementing healthcare as well as for those providing the evidence informing practice. Yet
Mainert, Jakob; Kretzschmar, André; Neubert, Jonas C.; Greiff, Samuel
2015-01-01
Transversal skills, such as complex problem solving (CPS) are viewed as central twenty-first-century skills. Recent empirical findings have already supported the importance of CPS for early academic advancement. We wanted to determine whether CPS could also contribute to the understanding of career advancement later in life. Towards this end, we…
The Complexity of the Consistency and N-representability Problems for Quantum States
Liu, Yi-Kai
2007-01-01
QMA (Quantum Merlin-Arthur) is the quantum analogue of the class NP. There are a few QMA-complete problems, most notably the ``Local Hamiltonian'' problem introduced by Kitaev. In this dissertation we show some new QMA-complete problems. The first one is ``Consistency of Local Density Matrices'': given several density matrices describing different (constant-size) subsets of an n-qubit system, decide whether these are consistent with a single global state. This problem was first suggested by Aharonov. We show that it is QMA-complete, via an oracle reduction from Local Hamiltonian. This uses algorithms for convex optimization with a membership oracle, due to Yudin and Nemirovskii. Next we show that two problems from quantum chemistry, ``Fermionic Local Hamiltonian'' and ``N-representability,'' are QMA-complete. These problems arise in calculating the ground state energies of molecular systems. N-representability is a key component in recently developed numerical methods using the contracted Schrodinger equation...
Modelling of Octahedral Manganese II Complexes with Inorganic Ligands: A Problem with Spin-States
Directory of Open Access Journals (Sweden)
Ludwik Adamowicz
2003-08-01
Full Text Available Abstract: Quantum mechanical ab initio UHF, MP2, MC-SCF and DFT calculations with moderate Gaussian basis sets were performed for MnX6, X = H2O, F-, CN-, manganese octahedral complexes. The correct spin-state of the complexes was obtained only when the counter ions neutralizing the entire complexes were used in the modelling at the B3LYP level of theory.
Yates, Jennifer L.
2011-01-01
The purpose of this research study was to explore the process of learning and development of problem solving skills in radiologic technologists. The researcher sought to understand the nature of difficult problems encountered in clinical practice, to identify specific learning practices leading to the development of professional expertise, and to…
Synthesis of Complex Natural Products as a Vehicle for Student-Centered, Problem-Based Learning
Cannon, Kevin J.; Krow, Grant R.
1998-10-01
Management strategies for upper-level undergraduate and graduate courses in organic synthesis at Temple University are described, and both student and faculty responsibilities are discussed. Using natural product synthesis as a vehicle, students choose a synthetic problem from the literature, identify the knowledge needed to solve the problem, explore resources for attaining that knowledge, identify the goals and criteria for a successful synthetic plan, and create and do assessments of their work. The method is an example of teacher-guided, student-directed, interdependent, small-group, problem-based learning.
Directory of Open Access Journals (Sweden)
Ward Paul R
2011-08-01
Full Text Available Abstract Background In order to improve the health of the most vulnerable groups in society, the WHO Commission on Social Determinants of Health (CSDH called for multi-sectoral action, which requires research and policy on the multiple and inter-linking factors shaping health outcomes. Most conceptual tools available to researchers tend to focus on singular and specific social determinants of health (SDH (e.g. social capital, empowerment, social inclusion. However, a new and innovative conceptual framework, known as social quality theory, facilitates a more complex and complete understanding of the SDH, with its focus on four domains: social cohesion, social inclusion, social empowerment and socioeconomic security, all within the same conceptual framework. This paper provides both an overview of social quality theory in addition to findings from a national survey of social quality in Australia, as a means of demonstrating the operationalisation of the theory. Methods Data were collected using a national random postal survey of 1044 respondents in September, 2009. Multivariate logistic regression analysis was conducted. Results Statistical analysis revealed that people on lower incomes (less than $45000 experience worse social quality across all of the four domains: lower socio-economic security, lower levels of membership of organisations (lower social cohesion, higher levels of discrimination and less political action (lower social inclusion and lower social empowerment. The findings were mixed in terms of age, with people over 65 years experiencing lower socio-economic security, but having higher levels of social cohesion, experiencing lower levels of discrimination (higher social inclusion and engaging in more political action (higher social empowerment. In terms of gender, women had higher social cohesion than men, although also experienced more discrimination (lower social inclusion. Conclusions Applying social quality theory allows
Exponential-Time Algorithms and Complexity of NP-Hard Graph Problems
DEFF Research Database (Denmark)
Taslaman, Nina Sofia
NP-hard problems are deemed highly unlikely to be solvable in polynomial time. Still, one can often find algorithms that are substantially faster than brute force solutions. This thesis concerns such algorithms for problems from graph theory; techniques for constructing and improving this type...... of algorithms, as well as investigations into how far such improvements can get under reasonable assumptions. The first part is concerned with detection of cycles in graphs, especially parameterized generalizations of Hamiltonian cycles. A remarkably simple Monte Carlo algorithm is presented......, referred to as the Tutte plane in this context. Under the Exponential Time Hypothesis, which claims a certain exponential-time requirement for solving the problem 3-Sat, superpolynomial lower bounds are given for problems restricted to simple or planar graphs. The restriction to simple graphs has been...
Information problem solving by experts and novices: Analysis of a complex cognitive skill.
Brand-Gruwel, Saskia; Wopereis, Iwan; Vermetten, Yvonne
2007-01-01
In (higher) education students are often faced with information problems: tasks or assignments that require them to identify information needs, locate corresponding information sources, extract and organize relevant information from each source, and synthesize information from a variety of sources.
Directory of Open Access Journals (Sweden)
A. V. Skrypnikov
2015-01-01
Full Text Available Summary. In this work the general ideas of a method of V. I. Skurikhin taking into account the specified features develop and questions of the analysis and synthesis of a complex of technical means, with finishing them to the level suitable for use in engineering practice of design of information management systems are in more detail considered. In work the general system approach to the solution of questions of a choice of technical means of the information management system is created, the general technique of the sys tem analysis and synthesis of a complex of the technical means and its subsystems providing achievement of extreme value of criterion of efficiency of functioning of a technical complex of the information management system is developed. The main attention is paid to the applied party of system researches of complex technical providing, in particular, to definition of criteria of quality of functioning of a technical complex, development of methods of the analysis of information base of the information management system and definition of requirements to technical means, and also methods of structural synthesis of the main subsystems of complex technical providing. Thus, the purpose is research on the basis of system approach of complex technical providing the information management system and development of a number of methods of the analysis and the synthesis of complex technical providing suitable for use in engineering practice of design of systems. The well-known paradox of development of management information consists of that parameters of the system, and consequently, and requirements to the complex hardware, can not be strictly reasonable to development of algorithms and programs, and vice versa. The possible method of overcoming of these difficulties is prognostication of structure and parameters of complex hardware for certain management informations on the early stages of development, with subsequent clarification and
Bringing the Unidata IDV to the Cloud
Fisher, W. I.; Oxelson Ganter, J.
2015-12-01
Maintaining software compatibility across new computing environments and the associated underlying hardware is a common problem for software engineers and scientific programmers. While traditional software engineering provides a suite of tools and methodologies which may mitigate this issue, they are typically ignored by developers lacking a background in software engineering. Causing further problems, these methodologies are best applied at the start of project; trying to apply them to an existing, mature project can require an immense effort. Visualization software is particularly vulnerable to this problem, given the inherent dependency on particular graphics hardware and software API's. As a result of these issues, there exists a large body of software which is simultaneously critical to the scientists who are dependent upon it, and yet increasingly difficult to maintain.The solution to this problem was partially provided with the advent of Cloud Computing; Application Streaming. This technology allows a program to run entirely on a remote virtual machine while still allowing for interactivity and dynamic visualizations, with little-to-no re-engineering required. When coupled with containerization technology such as Docker, we are able to easily bring the same visualization software to a desktop, a netbook, a smartphone, and the next generation of hardware, whatever it may be.Unidata has been able to harness Application Streaming to provide a tablet-compatible version of our visualization software, the Integrated Data Viewer (IDV). This work will examine the challenges associated with adapting the IDV to an application streaming platform, and include a brief discussion of the underlying technologies involved.
Directory of Open Access Journals (Sweden)
José Antonio Martín H
Full Text Available Many practical problems in almost all scientific and technological disciplines have been classified as computationally hard (NP-hard or even NP-complete. In life sciences, combinatorial optimization problems frequently arise in molecular biology, e.g., genome sequencing; global alignment of multiple genomes; identifying siblings or discovery of dysregulated pathways. In almost all of these problems, there is the need for proving a hypothesis about certain property of an object that can be present if and only if it adopts some particular admissible structure (an NP-certificate or be absent (no admissible structure, however, none of the standard approaches can discard the hypothesis when no solution can be found, since none can provide a proof that there is no admissible structure. This article presents an algorithm that introduces a novel type of solution method to "efficiently" solve the graph 3-coloring problem; an NP-complete problem. The proposed method provides certificates (proofs in both cases: present or absent, so it is possible to accept or reject the hypothesis on the basis of a rigorous proof. It provides exact solutions and is polynomial-time (i.e., efficient however parametric. The only requirement is sufficient computational power, which is controlled by the parameter α∈N. Nevertheless, here it is proved that the probability of requiring a value of α>k to obtain a solution for a random graph decreases exponentially: P(α>k≤2(-(k+1, making tractable almost all problem instances. Thorough experimental analyses were performed. The algorithm was tested on random graphs, planar graphs and 4-regular planar graphs. The obtained experimental results are in accordance with the theoretical expected results.
Bishop, Brian J; Dzidic, Peta L
2014-03-01
Causal layered analysis (CLA) is an emerging qualitative methodology adopted in the discipline of planning as an approach to deconstruct complex social issues. With psychologists increasingly confronted with complex, and "wicked" social and community issues, we argue that the discipline of psychology would benefit from adopting CLA as an analytical method. Until now, the application of CLA for data interpretation has generally been poorly defined and overwhelming for the novice. In this paper we propose an approach to CLA that provides a method for the deconstruction and analysis of complex social psychological issues. We introduce CLA as a qualitative methodology well suited for psychology, introduce the epistemological foundations of CLA, define a space for it adoption within the discipline, and, outline the steps for conducting a CLA using an applied example.
Problems and prospects of integration development of oil and gas complex in the south of Russia
Directory of Open Access Journals (Sweden)
Nikitaeva Anastasia, Y.
2015-06-01
Full Text Available Macroeconomic transformations of the global energy market in recent years have formed the basic tendency of development of modern oil and gas complex – consolidation and integration of companies in the industry to maintain its competitiveness and ensure sustainable strategic business development. In this regard, the issues of building effective mechanisms of partnership interactions and management of integration processes of oil and gas complex at the national and regional levels become relevant. The authors describe the specific operating conditions of oil and gas companies in southern Russia, identify obstacles to the region's integration into the structure of the Russian oil and gas industry, and formulate directions and measures activation of innovative development of oil and gas complex in the South of Russia.
Institute of Scientific and Technical Information of China (English)
Chen Li; Ma He-Ping; Cheng Yu-Min
2013-01-01
In this paper,the complex variable reproducing kernel particle (CVRKP) method and the finite element (FE) method are combined as the CVRKP-FE method to solve transient heat conduction problems.The CVRKP-FE method not only conveniently imposes the essential boundary conditions,but also exploits the advantages of the individual methods while avoiding their disadvantages,then the computational efficiency is higher.A hybrid approximation function is applied to combine the CVRKP method with the FE method,and the traditional difference method for two-point boundary value problems is selected as the time discretization scheme.The corresponding formulations of the CVRKP-FE method are presented in detail.Several selected numerical examples of the transient heat conduction problems are presented to illustrate the performance of the CVRKP-FE method.
Kobylkin, Konstantin
2016-10-01
Computational complexity and approximability are studied for the problem of intersecting of a set of straight line segments with the smallest cardinality set of disks of fixed radii r > 0 where the set of segments forms straight line embedding of possibly non-planar geometric graph. This problem arises in physical network security analysis for telecommunication, wireless and road networks represented by specific geometric graphs defined by Euclidean distances between their vertices (proximity graphs). It can be formulated in a form of known Hitting Set problem over a set of Euclidean r-neighbourhoods of segments. Being of interest computational complexity and approximability of Hitting Set over so structured sets of geometric objects did not get much focus in the literature. Strong NP-hardness of the problem is reported over special classes of proximity graphs namely of Delaunay triangulations, some of their connected subgraphs, half-θ6 graphs and non-planar unit disk graphs as well as APX-hardness is given for non-planar geometric graphs at different scales of r with respect to the longest graph edge length. Simple constant factor approximation algorithm is presented for the case where r is at the same scale as the longest edge length.
Field dependence as a limiting factor in solving a complex learning problem.
Robertson, R J; Alfano, P
1985-08-01
Subjects in a prior study of complex learning often experienced difficulty in mastering the task because of an apparent reluctance to release one perceptual field and reconstrue the task on a higher cognitive level. It was hypothesized that were this the correct explanation, the faster learners would be more field independent on a measure of field dependence, since independence has been defined in terms of ease in releasing one's attention from the immediate perceptual field. This hypothesis was tested with 22 undergraduate subjects for whom Group Embedded Figures Test scores were correlated with the number of trials to completion on the complex learning task. A moderate but significant correlation supported the hypothesis.
SIPPI: A Matlab toolbox for sampling the solution to inverse problems with complex prior information
DEFF Research Database (Denmark)
Hansen, Thomas Mejer; Cordua, Knud Skou; Caroline Looms, Majken
2013-01-01
on the solution. The combined states of information (i.e. the solution to the inverse problem) is a probability density function typically referred to as the a posteriori probability density function. We present a generic toolbox for Matlab and Gnu Octave called SIPPI that implements a number of methods...
SIPPI: A Matlab toolbox for sampling the solution to inverse problems with complex prior information
DEFF Research Database (Denmark)
Hansen, Thomas Mejer; Cordua, Knud Skou; Looms, Majken Caroline
2013-01-01
We present an application of the SIPPI Matlab toolbox, to obtain a sample from the a posteriori probability density function for the classical tomographic inversion problem. We consider a number of different forward models, linear and non-linear, such as ray based forward models that rely...
Institute of Scientific and Technical Information of China (English)
HE; Shanglu
2001-01-01
［1］Andersen, E. D., Ye, Y., On homogeneous algorithm for the monotone complementarity problem, Mathematical Programming, 1999, 84(2): 375.［2］Wright, S., Ralph, D., A supperlinear infeasible-interior-point algorithm for monotone complementarity problems, Mathematics of Operations Research, 1996, 24(4): 815.［3］Kojima, M., Noma, T., Yoshise, A., Global convergence in infeasible-interior-point algorithms, Mathematical Programming, 1994, 65(1): 43.［4］Kojima, M., Megiddo, N., Noma, T., A new continuation method for complementarity problems with uniform p-functions, Mathematical Programming, 1989, 43(1): 107.［5］Kojima, M., Megiddo, N., Mizuno, S., A general framework of continuation method for complementarity problems, Mathematics of Operations Research, 1993, 18(4): 945.［6］More, J., Rheinboldt, W., On P- and S-functions and related classes of n-dimensional nonlinear mappings, Linear Algebra and Its Applications, 1973, 6(1): 45.
Hill, Jennie; Powlitch, Stephanie; Furniss, Frederick
2008-01-01
The current study aimed to replicate and extend Rojahn et al. [Rojahn, J., Aman, M. G., Matson, J. L., & Mayville, E. (2003). "The aberrant behavior checklist and the behavior problems inventory: Convergent and divergent validity." "Research in Developmental Disabilities", 24, 391-404] by examining the convergent validity of the behavior problems…
Tight complexity bounds for FPT subgraph problems parameterized by clique-width
Broersma, Hajo; Golovach, Petr A.; Patel, Viresh; Marx, D.; Rossmanith, P.
2012-01-01
We give tight algorithmic lower and upper bounds for some double-parameterized subgraph problems when the clique-width of the input graph is one of the parameters. Let G be an arbitrary input graph on n vertices with clique-width at most w. We prove the following results. The Dense (Sparse) k -Subgr
Energy Technology Data Exchange (ETDEWEB)
Ropartz, David, E-mail: David.Ropartz@nantes.inra.fr [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France); Lemoine, Jérôme [Institut des Sciences Analytiques, UMR 5280, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Giuliani, Alexandre [Synchrotron SOLEIL, L’Orme des Merisiers, F-91190 Gif-sur-Yvette (France); UAR 1008 CEPIA, INRA, F-44316 Nantes (France); Bittebière, Yann [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France); Enjalbert, Quentin [Institut des Sciences Analytiques, UMR 5280, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Antoine, Rodolphe; Dugourd, Philippe [Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Ralet, Marie-Christine; Rogniaux, Hélène [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France)
2014-01-07
Graphical abstract: -- Highlights: •A complex mixture of methylated oligogalacturonans was fractionated by IP-RP-UHPLC. •Synchrotron-radiation in VUV range was used as an activation process for tandem MS. •VUV activation brought rich structural information compared to LE-CAD. •Resolution of more than 35 structures, including isomers, was successfully completed. -- Abstract: Carbohydrates have a wide variety of structures whose complexity and heterogeneity challenge the field of analytical chemistry. Tandem mass spectrometry, with its remarkable sensitivity and high information content, provides key advantages to addressing the structural elucidation of polysaccharides. Yet, classical fragmentation by collision-activated dissociation (CAD) in many cases fails to reach a comprehensive structural determination, especially when isomers have to be differentiated. In this work, for the first time, vacuum ultra-violet (VUV) synchrotron radiation is used as the activation process in tandem mass spectrometry of large oligosaccharides. Compared to low energy CAD (LE-CAD), photon activated dissociation brought more straightforward and valuable structural information. The outstanding feature was that complete series of informative ions were produced, with only minor neutral losses. Moreover, systematic fragmentation rules could be drawn thus facilitating the definitive assignments of fragment identities. As a result, most of the structures present in a complex mixture of oligogalacturonans could be comprehensively resolved, including many isomers differing in the position of methyl groups along the galacturonic acid backbone.
The Complexities of Participatory Action Research and the Problems of Power, Identity and Influence
Hawkins, Karen A.
2015-01-01
This article highlights the complexity of participatory action research (PAR) in that the study outlined was carried out with and by, as opposed to on, participants. The project was contextualised in two prior-to-school settings in Australia, with the early childhood professionals and, to some extent, the preschoolers involved in this PAR project…
Foucault as Complexity Theorist: Overcoming the Problems of Classical Philosophical Analysis
Olssen, Mark
2008-01-01
This article explores the affinities and parallels between Foucault's Nietzschean view of history and models of complexity developed in the physical sciences in the twentieth century. It claims that Foucault's rejection of structuralism and Marxism can be explained as a consequence of his own approach which posits a radical ontology whereby the…
Eseryel, Deniz; Ge, Xun; Ifenthaler, Dirk; Law, Victor
2011-01-01
Following a design-based research framework, this article reports two empirical studies with an educational MMOG, called "McLarin's Adventures," on facilitating 9th-grade students' complex problem-solving skill acquisition in interdisciplinary STEM education. The article discusses the nature of complex and ill-structured problem solving…
Eseryel, Deniz; Ge, Xun; Ifenthaler, Dirk; Law, Victor
2011-01-01
Following a design-based research framework, this article reports two empirical studies with an educational MMOG, called "McLarin's Adventures," on facilitating 9th-grade students' complex problem-solving skill acquisition in interdisciplinary STEM education. The article discusses the nature of complex and ill-structured problem solving and,…
Lower Bound for the Communication Complexity of the Russian Cards Problem
Cyriac, Aiswarya
2008-01-01
In this paper it is shown that no public announcement scheme that can be modelled in Dynamic Epistemic Logic (DEL) can solve the Russian Cards Problem (RCP) in one announcement. Since DEL is a general model for any public announcement scheme we conclude that there exist no single announcement solution to the RCP. The proof demonstrates the utility of DEL in proving lower bounds for communication protocols.
Methods of Optimization and Systems Analysis for Problems of Transcomputational Complexity
Sergienko, Ivan V
2012-01-01
This work presents lines of investigation and scientific achievements of the Ukrainian school of optimization theory and adjacent disciplines. These include the development of approaches to mathematical theories, methodologies, methods, and application systems for the solution of applied problems in economy, finances, energy saving, agriculture, biology, genetics, environmental protection, hardware and software engineering, information protection, decision making, pattern recognition, self-adapting control of complicated objects, personnel training, etc. The methods developed include sequentia
New noise-based logic representations to avoid some problems with time complexity
Wen, H; Klappenecker, A; Peper, F
2011-01-01
Instantaneous noise-based logic can avoid time-averaging, which implies significant potential for low-power parallel operations in beyond-Moore-law-chips. However, the universe (uniform superposition) will be zero with high probability (non-zero with exponentially low probability) in the random-telegraph-wave representation thus the operations with the universe would require exponential time-complexity. To fix this deficiency, we modify the amplitudes of the signals of the L and H states and achieve an exponential speedup compared to the old situation. Another improvement concerns the identification of a single product (hyperspace) state. We introduce a time shifted noise-based logic, which is constructed by shifting each reference signal with a small time delay. This modification implies an exponential speedup of single hyperspace vector identification compared to the former case and it requires the same, O(N) complexity as in quantum computing.
Complexity of matrix organization and problems caused by its inadequate implementation
Directory of Open Access Journals (Sweden)
Janićijević Nebojša
2007-01-01
Full Text Available Matrix organization model is a sophisticated structure intended to combine both the efficiency and effectiveness of the functional and the product/service/customer/area dimensions. From the moment it was introduced in practice, this organizational architecture was accepted with enthusiasm, because it represented a complex organizational response adequate to the conditions which most of the companies in the world have been facing since 1970s. Although matrix organization is not a novelty, it is still a controversial model of organization design. The aim of this paper is to provide a deeper insight into the causes and effects of organizational misfits which appear in the implementation phase of three-dimensional matrix organization, as well as to offer some practical recommendations for managers on how to improve their capacities for successful management of complex matrix organization architecture in their organizations.
Berry, Vincent; Nicolas, François
2006-01-01
Given a set of evolutionary trees on a same set of taxa, the maximum agreement subtree problem (MAST), respectively, maximum compatible tree problem (MCT), consists of finding a largest subset of taxa such that all input trees restricted to these taxa are isomorphic, respectively compatible. These problems have several applications in phylogenetics such as the computation of a consensus of phylogenies obtained from different data sets, the identification of species subjected to horizontal gene transfers and, more recently, the inference of supertrees, e.g., Trees Of Life. We provide two linear time algorithms to check the isomorphism, respectively, compatibility, of a set of trees or otherwise identify a conflict between the trees with respect to the relative location of a small subset of taxa. Then, we use these algorithms as subroutines to solve MAST and MCT on rooted or unrooted trees of unbounded degree. More precisely, we give exact fixed-parameter tractable algorithms, whose running time is uniformly polynomial when the number of taxa on which the trees disagree is bounded. The improves on a known result for MAST and proves fixed-parameter tractability for MCT.
Directory of Open Access Journals (Sweden)
Syed Tauseef Mohyud-Din
2015-01-01
Full Text Available This paper witnesses the coupling of an analytical series expansion method which is called reduced differential transform with fractional complex transform. The proposed technique is applied on three mathematical models, namely, fractional Kaup-Kupershmidt equation, generalized fractional Drinfeld-Sokolov equations, and system of coupled fractional Sine-Gordon equations subject to the appropriate initial conditions which arise frequently in mathematical physics. The derivatives are defined in Jumarie’s sense. The accuracy, efficiency, and convergence of the proposed technique are demonstrated through the numerical examples. It is observed that the presented coupling is an alternative approach to overcome the demerit of complex calculation of fractional differential equations. The proposed technique is independent of complexities arising in the calculation of Lagrange multipliers, Adomian’s polynomials, linearization, discretization, perturbation, and unrealistic assumptions and hence gives the solution in the form of convergent power series with elegantly computed components. All the examples show that the proposed combination is a powerful mathematical tool to solve other nonlinear equations also.
On the Problem of Optimizing Parallel Programs for Complex Memory Hierarchies
Institute of Scientific and Technical Information of China (English)
金国华; 陈福接
1994-01-01
Based on a thorough study of the relationship between array element accesses and loop indices of the nested loop,a method is presented with which the staggering relation and the compacting relation between the threads of the nested loop (either with a single linear function of with multiple linear functions) can be determined at compile-time,and accordingly the nested loop (either perfectly nested one or imperfectly nested one) can be restructured to avoid the thrashing problem.Due to its simplicity,our method can be efficiently implemented in any parallel compiler,and the improvement of the performance is significant as shown be the experimental results.
Fibromyalgia and Disability Adjudication: No Simple Solutions to a Complex Problem
Directory of Open Access Journals (Sweden)
Manfred Harth
2014-01-01
Full Text Available BACKGROUND: Adjudication of disability claims related to fibromyalgia (FM syndrome can be a challenging and complex process. A commentary published in the current issue of Pain Research & Management makes suggestions for improvement. The authors of the commentary contend that: previously and currently used criteria for the diagnosis of FM are irrelevant to clinical practice; the opinions of family physicians should supersede those of experts; there is little evidence that trauma can cause FM; no formal instruments are necessary to assess disability; and many FM patients on or applying for disability are exaggerating or malingering, and tests of symptoms validity should be used to identify malingerers.
Traveling salesman problems with PageRank Distance on complex networks reveal community structure
Jiang, Zhongzhou; Liu, Jing; Wang, Shuai
2016-12-01
In this paper, we propose a new algorithm for community detection problems (CDPs) based on traveling salesman problems (TSPs), labeled as TSP-CDA. Since TSPs need to find a tour with minimum cost, cities close to each other are usually clustered in the tour. This inspired us to model CDPs as TSPs by taking each vertex as a city. Then, in the final tour, the vertices in the same community tend to cluster together, and the community structure can be obtained by cutting the tour into a couple of paths. There are two challenges. The first is to define a suitable distance between each pair of vertices which can reflect the probability that they belong to the same community. The second is to design a suitable strategy to cut the final tour into paths which can form communities. In TSP-CDA, we deal with these two challenges by defining a PageRank Distance and an automatic threshold-based cutting strategy. The PageRank Distance is designed with the intrinsic properties of CDPs in mind, and can be calculated efficiently. In the experiments, benchmark networks with 1000-10,000 nodes and varying structures are used to test the performance of TSP-CDA. A comparison is also made between TSP-CDA and two well-established community detection algorithms. The results show that TSP-CDA can find accurate community structure efficiently and outperforms the two existing algorithms.
Motion artifacts in MRI: A complex problem with many partial solutions.
Zaitsev, Maxim; Maclaren, Julian; Herbst, Michael
2015-10-01
Subject motion during magnetic resonance imaging (MRI) has been problematic since its introduction as a clinical imaging modality. While sensitivity to particle motion or blood flow can be used to provide useful image contrast, bulk motion presents a considerable problem in the majority of clinical applications. It is one of the most frequent sources of artifacts. Over 30 years of research have produced numerous methods to mitigate or correct for motion artifacts, but no single method can be applied in all imaging situations. Instead, a "toolbox" of methods exists, where each tool is suitable for some tasks, but not for others. This article reviews the origins of motion artifacts and presents current mitigation and correction methods. In some imaging situations, the currently available motion correction tools are highly effective; in other cases, appropriate tools still need to be developed. It seems likely that this multifaceted approach will be what eventually solves the motion sensitivity problem in MRI, rather than a single solution that is effective in all situations. This review places a strong emphasis on explaining the physics behind the occurrence of such artifacts, with the aim of aiding artifact detection and mitigation in particular clinical situations.
Institute of Scientific and Technical Information of China (English)
XiangYu; HuangYuying; MaXiaoqiang
2004-01-01
By virtue of the comparability between the wave superposition method and the dynamic analysis of structures, a general format for overcoming the non-uniqueness of solution induced by the wave superposition method at the eigenfrequencies of the corresponding interior problems is proposed. By adding appropriate damp to the virtual source system of the wave superposition method, the unique solutions for all wave numbers can be ensured. Based on this thought, a novel method-wave superposition method with complex radius vector is constructed.Not only is the computational time of this method approximately equal to that of the standard wave superposition method, but also the accuracy is much higher compared with other correlative methods. Finally, by taking the pulsating sphere and oscillating sphere as examples, the results of calculation show that the present method can effectively overcome the non-uniqueness problem.
Nagata, Keitaro; Nishimura, Jun; Shimasaki, Shinji
2016-01-01
We study full QCD at finite density and low temperature with light quark mass using the complex Langevin method. Since the singular drift problem turns out to be mild on a $4^3 \\times 8$ lattice we use, the gauge cooling is performed only to control the unitarity norm in this exploratory study. We report on our preliminary data obtained from the complex Langevin simulation up to certain Langevin time. While the data are still noisy due to lack of statistics, the onset of the baryon number density seems to occur at larger $\\mu$ than half the pion mass, which is the value for the phase quenched QCD. The validity of our simulation is tested by the recently proposed criterion based on the probability distribution of the drift term.
Epting, Shane
2016-12-01
Transportation infrastructure tremendously affects the quality of life for urban residents, influences public and mental health, and shapes social relations. Historically, the topic is rich with social and political controversy and the resultant transit systems in the United States cause problems for minority residents and issues for the public. Environmental justice frameworks provide a means to identify and address harms that affect marginalized groups, but environmental justice has limits that cannot account for the mainstream population. To account for this condition, I employ a complex moral assessment measure that provides a way to talk about harms that affect the public.
Bringing Power to Planning Research
DEFF Research Database (Denmark)
Flyvbjerg, Bent
of how the methodology he developed for power studies, called "phronetic planning research," may be employed in practice. Phronetic planning research follows the tradition of power studies running from Machiavelli and Nietzsche to Michel Foucault and Pierre Bourdieu. It focuses on four value......This article provides an answer to what has been called the biggest problem in theorizing and understanding planning, namely the ambivalence about power found among planning researchers, theorists, and students. The author narrates how he came to work with issues of power. He then gives an example......-rational questions: (1) Where are we going with planning? (2) Who gains and who loses, and by which mechanisms of power? (3) Is this development desirable? (4) What should be done? These questions are exemplified for a specific instance of Scandinavian urban planning. The author finds that the questions...
Bringing Power to Planning Research
DEFF Research Database (Denmark)
Flyvbjerg, Bent
2002-01-01
This article provides an answer to what has been called the biggest problem in theorizing and understanding planning, namely the ambivalence about power found among planning researchers, theorists, and students. The author narrates how he came to work with issues of power. He then gives an example...... of how the methodology he developed for power studies, called "phronetic planning research," may be employed in practice. Phronetic planning research follows the tradition of power studies running from Machiavelli and Nietzsche to Michel Foucault and Pierre Bourdieu. It focuses on four value......-rational questions: (1) Where are we going with planning? (2) Who gains and who loses, and by which mechanisms of power? (3) Is this development desirable? (4) What should be done? These questions are exemplified for a specific instance of Scandinavian urban planning. The author finds that the questions...
Economic Problems of Oil and Gas Complex Development in the Northern Territories of Russia
Directory of Open Access Journals (Sweden)
Elena G. Katysheva
2016-11-01
Full Text Available The main economic problems of oil and gas fields development in the Arctic zone of the Russian Federation in the conditions of an economic crisis and an adverse foreign policy situation are characterized in this article. The main way to decrease the influence of sanctions in the sphere of oil and gas extraction is significant decline in the market share of foreign companies using import substitution. It has to be mentioned that localization of equipment production and development of technologies for sea oil and gas production in the Arctic zone of the Russian Federation can become incentive for import substitution, and attracting foreign investments into the Russian oil and gas sector. Nowadays an experience of the Arctic defense enterprises has significantly increased in the sphere of the equipment production for oil and gas extraction and processing. The most significant examples of creation of new productions in the Arctic zone are given in this article. The particular attention is given to development prospects of seismic works in the Arctic shelf under sanctions and fall in oil prices. The Russian sea geophysical companies aren't equipped with modern specialized ships for holding 3D seismic exploration. As a result the seismic works which are carried out now on the Russian shelf 3D in technological parameters considerably lag behind world level. However ensuring of import substitution in the sphere of geophysical oilfield service is accompanied by a number of serious economic problems. It is concluded that drawn that localization of production capacities and service bases near the Arctic shelf will provide multiplicative economic effect, and also will serve as incentive to qualitatively new industrial and infrastructural development of northern territories
Using the complex Langevin equation to solve the sign problem of QCD
Energy Technology Data Exchange (ETDEWEB)
Sexty, Denes [Bergische Univ. Wuppertal (Germany)
2016-11-01
Using the resources of SuperMUC we have been able to calculate the reweighting results and compare them to the CLE for lattice sizes up to Nt=8. This did not allow the exploration of the phase transition line. It's an open question whether increasing the lattice size will allow us to go to smaller temperatures. The cost of larger lattices is of course increasing, especially the reweighting becomes much more expensive at larger volumes, as it's cost is proportional to the spatial volume cubed. An other important open question is the question of the poles: the fermionic drift term has singularities on the complex manifold, which in some cases can lead to the breakdown of the method, but it is unknown what its effect is on QCD, especially at low temperatures.
Bringing customers into the boardroom.
McGovern, Gail J; Court, David; Quelch, John A; Crawford, Blair
2004-11-01
Misguided marketing strategies have destroyed more shareholder value than shoddy accounting or shady fiscal practices. Yet marketing functions typically reside deep in the organization, far from the executive suite and boardroom, and they are often poorly aligned with corporate strategy. Boards of directors, it would seem, have compelling reasons to monitor their companies' marketing activities. The authors argue that boards lack a clear understanding of how their companies are meeting customers' needs and how their marketing strategies drive (or often fail to drive) top-line growth. To help remedy that problem, they've devised a "marketing dashboard," a series of management reports that could give the board this critical knowledge. The dashboard has three parts, each of which the board should review regularly. The first part tracks the company's main business drivers--those business conditions that, when manipulated or otherwise changed, will directly and predictably affect the company's performance. The second part describes the specific innovations in a pipeline of growth ideas that will allow the company to reach its short- and long-term revenue goals. And the third part provides an overview of the company's marketing skill set so the board can determine not only if the company has enough marketing talent but also if it has the right marketing talent. Unlike isolated measures of marketing performance that are often insufficient, irrelevant, or misleading, the dashboard allows the board to quickly and routinely assess the effectiveness of its company's marketing strategies. Armed with a clear understanding of marketing's role and performance, the board can expose inadequate marketing campaigns, direct management to address the problem, and monitor progress.
On Advice Complexity of the k-server Problem under Sparse Metrics
DEFF Research Database (Denmark)
Gupta, S.; Kamali, S.; López-Ortiz, A.
2013-01-01
We consider the k-Server problem under the advice model of computation when the underlying metric space is sparse. On one side, we introduce Θ (1)-competitive algorithms for a wide range of sparse graphs, which require advice of (almost) linear size. Namely, we show that for graphs of size N...... and treewidth α, there is an online algorithm which receives O (n(log α +log log N))1 bits of advice and optimally serves a sequence of length n. With a different argument, we show that if a graph admits a system of μ collective tree (q, r)- spanners, then there is a (q + r)-competitive algorithm which receives...... O (n(log μ +log logN)) bits of advice. Among other results, this gives a 3-competitive algorithm for planar graphs, provided with O (n log log N) bits of advice. On the other side, we show that an advice of size Ω (n) is required to obtain a 1-competitive algorithm for sequences of size n even...
On the Combinatorics of SAT and the Complexity of Planar Problems
DEFF Research Database (Denmark)
Talebanfard, Navid
construction of k-CNF instances that require running time at least 2(1−k)n, where k = O(log2 k/k). For DPLL ([22], [21]) we construct unsatisfiable hard instances requiring a running time of the same form, except with k = ˜O(k−1/3). This improves on a previous construction which gives k = ˜O (k−1/4). The depth...... of depth O(s2 log n). We also construct unsatisfiable formulas which are refutable in constant space but require logarithmic depth. This shows that at least for constant variable space the upper bound is sharp. Another problem we consider is to give sharp bounds for the number of prime implicants of k......-CNF formulas. For k = 2 we give a characterization of prime implicants and show that the maximum number of them is between 3n/3 and (1+o(1))3n/3. For k 3, we extend the Satisfiability Coding Lemma [41] and show that if each variable occurs in a constant number of clauses the number of prime implicant...
Ancel, Ersin; Shih, Ann T.
2014-01-01
This paper highlights the development of a model that is focused on the safety issue of increasing complexity and reliance on automation systems in transport category aircraft. Recent statistics show an increase in mishaps related to manual handling and automation errors due to pilot complacency and over-reliance on automation, loss of situational awareness, automation system failures and/or pilot deficiencies. Consequently, the aircraft can enter a state outside the flight envelope and/or air traffic safety margins which potentially can lead to loss-of-control (LOC), controlled-flight-into-terrain (CFIT), or runway excursion/confusion accidents, etc. The goal of this modeling effort is to provide NASA's Aviation Safety Program (AvSP) with a platform capable of assessing the impacts of AvSP technologies and products towards reducing the relative risk of automation related accidents and incidents. In order to do so, a generic framework, capable of mapping both latent and active causal factors leading to automation errors, is developed. Next, the framework is converted into a Bayesian Belief Network model and populated with data gathered from Subject Matter Experts (SMEs). With the insertion of technologies and products, the model provides individual and collective risk reduction acquired by technologies and methodologies developed within AvSP.
Directory of Open Access Journals (Sweden)
Chiara Biscarini
2013-01-01
Full Text Available The numerical simulation of fast-moving fronts originating from dam or levee breaches is a challenging task for small scale engineering projects. In this work, the use of fully three-dimensional Navier-Stokes (NS equations and lattice Boltzmann method (LBM is proposed for testing the validity of, respectively, macroscopic and mesoscopic mathematical models. Macroscopic simulations are performed employing an open-source computational fluid dynamics (CFD code that solves the NS combined with the volume of fluid (VOF multiphase method to represent free-surface flows. The mesoscopic model is a front-tracking experimental variant of the LBM. In the proposed LBM the air-gas interface is represented as a surface with zero thickness that handles the passage of the density field from the light to the dense phase and vice versa. A single set of LBM equations represents the liquid phase, while the free surface is characterized by an additional variable, the liquid volume fraction. Case studies show advantages and disadvantages of the proposed LBM and NS with specific regard to the computational efficiency and accuracy in dealing with the simulation of flows through complex geometries. In particular, the validation of the model application is developed by simulating the flow propagating through a synthetic urban setting and comparing results with analytical and experimental laboratory measurements.
Grover, Jeff
2016-01-01
This book is an extension of the author’s first book and serves as a guide and manual on how to specify and compute 2-, 3-, & 4-Event Bayesian Belief Networks (BBN). It walks the learner through the steps of fitting and solving fifty BBN numerically, using mathematical proof. The author wrote this book primarily for naïve learners and professionals, with a proof-based academic rigor. The author's first book on this topic, a primer introducing learners to the basic complexities and nuances associated with learning Bayes’ theory and inverse probability for the first time, was meant for non-statisticians unfamiliar with the theorem - as is this book. This new book expands upon that approach and is meant to be a prescriptive guide for building BBN and executive decision-making for students and professionals; intended so that decision-makers can invest their time and start using this inductive reasoning principle in their decision-making processes. It highlights the utility of an algorithm that served as ...
System sight at a problem of efficiency of enterprises’s operaton of the Russian chemical complex
Directory of Open Access Journals (Sweden)
Svyatoslav Arkadyevich Nikitin
2011-06-01
Full Text Available Chemical industry plays an important role in the development of the domestic economy as one of the basic facilities of Russia's economy, laying the foundation for its long-term and stable development. As a major supplier of raw materials, intermediates, and products of various materials (plastics, chemical fibers, tires, paints and varnishes, dyes, fertilizers, feed additives, pharmaceuticals, medical equipment etc. in almost all sectors of industry, agriculture, health care, human services, commerce, science, culture and education, defense industry, chemical complex has direct impact on the efficiency of their operation and development in these new directions. Therefore, the condition and development of domestic chemistry determines the level of national competitiveness, economic growth and Russia's wealth. However, like most industries in Russia today, chemical industry is going through a difficult period. The presence of a set of common economic problems (identified by technological backwardness and high depreciation, low innovation activity of domestic enterprises of the chemical complex, a lack of effectiveness of the investment process, infrastructure and resource constraints etc., as well as internal management problems causes the rapid growth of interest of uncompetitive Russian chemical products on the world market. Under these conditions, not only a radical adjustment of the internal control systems and chemical plants, but also a significant organizational and economic change is required. Thus, unless we take measures to improve the domestic chemical industry in the coming years, almost all of it grow back and may get into the situation of struggle for survival.
Develaki, Maria
2008-09-01
In view of the complex problems of this age, the question of the socio-ethical dimension of science acquires particular importance. We approach this matter from a philosophical and sociological standpoint, looking at such focal concerns as the motivation, purposes and methods of scientific activity, the ambivalence of scientific research and the concomitant risks, and the conflict between research freedom and external socio-political intervention. We then point out the impediments to the effectiveness of cross-disciplinary or broader meetings for addressing these complex problems and managing the associated risks, given the difficulty in communication between experts in different fields and non-experts, difficulties that education is challenged to help resolve. We find that the social necessity of informed decision-making on the basis of cross-disciplinary collaboration is reflected in the newer curricula, such as that of Greece, in aims like the acquisition of cross-subject knowledge and skills, and the ability to make decisions on controversial issues involving value conflicts. The interest and the reflections of the science education community in these matters increase its—traditionally limited—contribution to the theoretical debate on education and, by extension, the value of science education in the education system.
Gershenson, Carlos
2011-01-01
The term complexity derives etymologically from the Latin plexus, which means interwoven. Intuitively, this implies that something complex is composed by elements that are difficult to separate. This difficulty arises from the relevant interactions that take place between components. This lack of separability is at odds with the classical scientific method - which has been used since the times of Galileo, Newton, Descartes, and Laplace - and has also influenced philosophy and engineering. In recent decades, the scientific study of complexity and complex systems has proposed a paradigm shift in science and philosophy, proposing novel methods that take into account relevant interactions.
Healthy Family 2009: Bringing in Baby
... Navigation Bar Home Current Issue Past Issues Healthy Family 2009 Bringing in Baby Past Issues / Winter 2009 ... Down syndrome and other common genetic disorders, inherited family conditions, such as Duchenne muscular dystrophy, or disorders ...
Zika Infection May Bring Future Immunity
... page: https://medlineplus.gov/news/fullstory_161496.html Zika Infection May Bring Future Immunity: Study Individuals, and ... HealthDay News) -- People who've been infected with Zika face a low risk for another bout with ...
Integrated system brings hospital data together.
Johnson, K F
1987-10-01
Healthcare industry changes during the 1980s--increased competition and alterations in the Medicare payment methodology--place new and more complex demands on a hospital's information systems, which often fall short of meeting those demands. These systems were designed for financial reporting, billing, or providing clinical data, and few of them are capable of linking with other unrelated systems. Today's hospital manager needs timely and simultaneous access to data from a variety of sources within the hospital. All the elements to accomplish this are collected somewhere in the hospital, but finding them and bringing them together is difficult. The key to the efficient management and use of data bases is in understanding the fundamental concept of relational data bases, which is the capability of linking or joining separate data files through a common data element in each file. In this way, data files may be integrated into a "related" data base. Any number of separate files, or tables, may exist within a "relational" data base as long as a series of threads links them. A strategic management information data base includes the information necessary to analyze, understand, and manage the hospital's markets, products, resources, and profitability. The major components of this information system are the case mix and cost accounting, budgeting, and modeling systems. The case mix and cost accounting factors involve managing concrete pieces of data, whereas the budgeting and modeling factors manipulate data to create a scenario. The strategic management information data base is the foundation of a hospital's decision support system, which is rapidly moving into the category of a necessary tool of the hospital manager's trade.
Bring Your Own Technology (BYOT) to Education
2014-01-01
In an effort to reduce costs and increase worker satisfaction, many businesses have implemented a concept known as Bring Your Own Device (BYOD) or Bring Your Own Technology (BYOT). Similarly, many school districts are beginning to implement BYOT policies and programs to improve educational learning opportunities for students who have a wide variety of technology devices. BYOT allow districts with limited budgets enable usage of technology while improving student engagement. This paper explore...
Bringing Space Crisis Stability Down to Earth
2015-01-01
JFQ 76, 1st Quarter 2015 Finch 15 Bringing Space Crisis Stability Down to Earth By James P. Finch T ensions in the South and East China seas have...0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing...2015 to 00-00-2015 4. TITLE AND SUBTITLE Bringing Space Crisis Stability Down to Earth 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT
Oches, E. A.; Szymanski, D. W.; Snyder, B.; Gulati, G. J.; Davis, P. T.
2012-12-01
The highly interdisciplinary nature of sustainability presents pedagogic challenges when sustainability concepts are incorporated into traditional disciplinary courses. At Bentley University, where over 90 percent of students major in business disciplines, we have created a multidisciplinary course module centered on corn ethanol that explores a complex social, environmental, and economic problem and develops basic data analysis and analytical thinking skills in several courses spanning the natural, physical, and social sciences within the business curriculum. Through an NSF-CCLI grant, Bentley faculty from several disciplines participated in a summer workshop to define learning objectives, create course modules, and develop an assessment plan to enhance interdisciplinary sustainability teaching. The core instructional outcome was a data-rich exercise for all participating courses in which students plot and analyze multiple parameters of corn planted and harvested for various purposes including food (human), feed (animal), ethanol production, and commodities exchanged for the years 1960 to present. Students then evaluate patterns and trends in the data and hypothesize relationships among the plotted data and environmental, social, and economic drivers, responses, and unintended consequences. After the central data analysis activity, students explore corn ethanol production as it relates to core disciplinary concepts in their individual classes. For example, students in Environmental Chemistry produce ethanol using corn and sugar as feedstocks and compare the efficiency of each process, while learning about enzymes, fermentation, distillation, and other chemical principles. Principles of Geology students examine the effects of agricultural runoff on surface water quality associated with extracting greater agricultural yield from mid-continent croplands. The American Government course examines the role of political institutions, the political process, and various
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
The Boltzmann simplified velocity distribution function equation describing the gas transfer phenomena from various flow regimes will be explored and solved numerically in this study. The discrete velocity ordinate method of the gas kinetic theory is studied and applied to simulate the complex multi-scale flows. Based on the uncoupling technique on molecular movement and colliding in the DSMC method, the gas-kinetic finite difference scheme is constructed to directly solve the discrete velocity distribution functions by extending and applying the unsteady time-splitting method from computational fluid dynamics. The Gauss-type discrete velocity numerical quadrature technique for different Mach number flows is developed to evaluate the macroscopic flow parameters in the physical space. As a result, the gas-kinetic numerical algorithm is established to study the three-dimensional complex flows from rarefied transition to continuum regimes. The parallel strategy adapted to the gas-kinetic numerical algorithm is investigated by analyzing the inner parallel degree of the algorithm, and then the HPF parallel processing program is developed. To test the reliability of the present gas-kinetic numerical method, the three-dimensional complex flows around sphere and spacecraft shape with various Knudsen numbers are simulated by HPF parallel computing. The computational results are found in high resolution of the flow fields and good agreement with the theoretical and experimental data. The computing practice has confirmed that the present gas-kinetic algorithm probably provides a promising approach to resolve the hypersonic aerothermodynamic problems with the complete spectrum of flow regimes from the gas-kinetic point of view of solving the Boltzmann model equation.
Roesch, Frank; Nerb, Josef; Riess, Werner
2015-01-01
Our study investigated whether problem-oriented designed ecology lessons with phases of direct instruction and of open experimentation foster the development of cross-domain and domain-specific components of "experimental problem-solving ability" better than conventional lessons in science. We used a paper-and-pencil test to assess…
Bring Your Own Technology (BYOT to Education
Directory of Open Access Journals (Sweden)
Joseph M. Woodside
2014-06-01
Full Text Available In an effort to reduce costs and increase worker satisfaction, many businesses have implemented a concept known as Bring Your Own Device (BYOD or Bring Your Own Technology (BYOT. Similarly, many school districts are beginning to implement BYOT policies and programs to improve educational learning opportunities for students who have a wide variety of technology devices. BYOT allow districts with limited budgets enable usage of technology while improving student engagement. This paper explores the technology devices, and educational implications of policies, device management, security and included components.
Bottge, B A; Hasselbring, T S
1993-05-01
Two groups of adolescents with learning difficulties in mathematics were compared on their ability to generate solutions to a contextualized problem after being taught problem-solving skills under two conditions, one involving standard word problems, the other involving a contextualized problem on videodisc. All problems focused on adding and subtracting fractions in relation to money and linear measurement. Both groups of students improved their performance on solving word problems, but students in the contextualized problem group did significantly better on the contextualized problem posttest and were able to use their skills in two transfer tasks that followed instruction.
Simons, J.
2008-01-01
This paper brings together narratology, game theory, and complexity theory to untangle the intricate nature of complex narratives in contemporary cinema. It interrogates the different terms - forking-path narratives, mind-game films, modular narratives, multiple-draft films, database narratives, puz
Complex Mapping of Aerofoils--A Different Perspective
Matthews, Miccal T.
2012-01-01
In this article an application of conformal mapping to aerofoil theory is studied from a geometric and calculus point of view. The problem is suitable for undergraduate teaching in terms of a project or extended piece of work, and brings together the concepts of geometric mapping, parametric equations, complex numbers and calculus. The Joukowski…
Mathematical models in biology bringing mathematics to life
Ferraro, Maria; Guarracino, Mario
2015-01-01
This book presents an exciting collection of contributions based on the workshop “Bringing Maths to Life” held October 27-29, 2014 in Naples, Italy. The state-of-the art research in biology and the statistical and analytical challenges facing huge masses of data collection are treated in this Work. Specific topics explored in depth surround the sessions and special invited sessions of the workshop and include genetic variability via differential expression, molecular dynamics and modeling, complex biological systems viewed from quantitative models, and microscopy images processing, to name several. In depth discussions of the mathematical analysis required to extract insights from complex bodies of biological datasets, to aid development in the field novel algorithms, methods and software tools for genetic variability, molecular dynamics, and complex biological systems are presented in this book. Researchers and graduate students in biology, life science, and mathematics/statistics will find the content...
DNA Barcoding Investigations Bring Biology to Life
Musante, Susan
2010-01-01
This article describes how DNA barcoding investigations bring biology to life. Biologists recognize the power of DNA barcoding not just to teach biology through connections to the real world but also to immerse students in the exciting process of science. As an investigator in the Program for the Human Environment at Rockefeller University in New…
Bringing Research into Educational Practice: Lessons Learned
Hille, Katrin
2011-01-01
Bringing research into educational practice is necessary but does not happen automatically. The Transfercenter for Neuroscience and Learning, at the University of Ulm in Germany, is set up to transfer (neuro)scientific knowledge into educational practice. In doing so we have learned why this does not happen automatically, and have tried to make…
Directory of Open Access Journals (Sweden)
Reza Khazaeli
2015-01-01
Full Text Available In this study, a version of thermal immersed boundary-Lattice Boltzmann method (TIB-LBM is used to simulate thermal flow problems within complex geometries. The present approach is a combination of the immersed boundary method (IBM and the thermal lattice Boltzmann method (TLBM under the double population approach. The method combines two different grid systems, an Eulerian grid for the flow domain and a Lagrangian grid for the boundary points immersed in the flow. In the present method, an unknown velocity correction is considered on the boundary points to impose the no-slip boundary condition. As a similar approach, an unknown internal energy correction on the boundary points is applied to satisfy the constant temperature boundary condition. The advantages of this approach are its second-order accuracy and straightforward calculation of the Nusselt number. The natural convection in an annulus with various outer cylinder shapes for different Rayleigh numbers have been simulated to demonstrate the capability and the accuracy of present approach. In terms of accuracy, the predicted results show an excellent agreement with those predicted by other experimental and numerical approaches.
Institute of Scientific and Technical Information of China (English)
YIN WeiPing; YIN XiaoLan
2009-01-01
Complex Monge-Amlère equation is a nonlinear equation with high degree,so its solutio nis very difficult to get. How to get the plurisubharmonic solution of Dirichlet problem of complex MongeAmpere equation on the Cartan-Hartogs domain of the second type is discussed by using the analytic order ordinary differential equation (ODE) by using quite different method. Secondly,the solution of the Dirichlet problem is given in semi-explicit formula,and under a special case the exact solution is obtained. These results may be helpful for the numerical method of Dirichlet problem of complex Monge-Ampere equation on the Cartan-Hartogs domain.
Bringing Breast Cancer Technologies to Market | Poster
CCR research is recognized in novel competition to encourage the commercialization of breast cancer inventions. Editor’s note: This article was originally published in CCR Connections (Volume 8, No. 1). The Breast Cancer Startup Challenge was named one of six finalists in the HHS Innovates Award Competition, and was one of three finalists recognized by HHS Secretary Sylvia Mathews Burwell and Deputy Secretary Bill Corr. For more information on the Challenge, see previous article on the Poster website. Start-up companies are instrumental in bringing the fruits of scientific research to market. Recognizing an opportunity to bring entrepreneurial minds to bear on the diagnosis and treatment of breast cancer, the Avon Foundation for Women partnered with NCI and the Center for Advancing Innovation to launch the Breast Cancer Startup Challenge.
Virtual Waterless Port:" BRING THE PORT FORWARD"
Institute of Scientific and Technical Information of China (English)
Wang Siyuan
2009-01-01
@@ To deal with the crisis,the central government of China carried out"ten major industries stimulating programme",which includes logistics and information industry.Lifting the development of logistics and information industry to a level of national strategy,it shows that the central governments is paying great attention to construct modern logistics service system,cut the costs and improve efficiency,bringing an opportunity for Chinese logistics industry.
China-Vietnam Friendship Bringing Light Tour
Institute of Scientific and Technical Information of China (English)
2010-01-01
<正>At the invitation of the Vietnam Union of Friendship Organizations (VUFO),a delegation headed by CPAFFC Vice President Feng Zuoku and composed of a medical team from Beijing Tongren Hospital made a"China-Vietnam Friendship Bringing Light Tour to Vietnam"from November 13 to 20,2009 and gave free cataract surgery to about 100 patients in Bac Giang Province.
Directory of Open Access Journals (Sweden)
G. F. Kutsenko
2006-01-01
Full Text Available The paper considers a number of problems concerning relations between power-supply organizations and agro-industrial complex enterprises in respect of reliability of power supply to electro-receivers. Some concrete measures that are supposed to improve these relations under modem conditions are offered in the paper/
Choi, Ikseon; Lee, Sang Joon; Kang, Jeongwan
2009-01-01
This study explores how students' learning styles influence their learning while solving complex problems when a case-based e-learning environment is implemented in a conventional lecture-oriented classroom. Seventy students from an anaesthesiology class at a dental school participated in this study over a 3-week period. Five learning-outcome…
A new DNA algorithm to solve graph coloring problem
Institute of Scientific and Technical Information of China (English)
Jiang Xingpeng; Li Yin; Meng Ya; Meng Dazhi
2007-01-01
Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing.However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size.Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R ).
Macian-Sorribes, Hector; Pulido-Velazquez, Manuel; Tilmant, Amaury
2015-04-01
Stochastic programming methods are better suited to deal with the inherent uncertainty of inflow time series in water resource management. However, one of the most important hurdles in their use in practical implementations is the lack of generalized Decision Support System (DSS) shells, usually based on a deterministic approach. The purpose of this contribution is to present a general-purpose DSS shell, named Explicit Stochastic Programming Advanced Tool (ESPAT), able to build and solve stochastic programming problems for most water resource systems. It implements a hydro-economic approach, optimizing the total system benefits as the sum of the benefits obtained by each user. It has been coded using GAMS, and implements a Microsoft Excel interface with a GAMS-Excel link that allows the user to introduce the required data and recover the results. Therefore, no GAMS skills are required to run the program. The tool is divided into four modules according to its capabilities: 1) the ESPATR module, which performs stochastic optimization procedures in surface water systems using a Stochastic Dual Dynamic Programming (SDDP) approach; 2) the ESPAT_RA module, which optimizes coupled surface-groundwater systems using a modified SDDP approach; 3) the ESPAT_SDP module, capable of performing stochastic optimization procedures in small-size surface systems using a standard SDP approach; and 4) the ESPAT_DET module, which implements a deterministic programming procedure using non-linear programming, able to solve deterministic optimization problems in complex surface-groundwater river basins. The case study of the Mijares river basin (Spain) is used to illustrate the method. It consists in two reservoirs in series, one aquifer and four agricultural demand sites currently managed using historical (XIV century) rights, which give priority to the most traditional irrigation district over the XX century agricultural developments. Its size makes it possible to use either the SDP or
Afterschool Universe - Bringing Astronomy Down to Earth
Krishnamurthi, Anita; Eyermann, S. E.; Mitchell, S.
2010-01-01
Bring the universe beyond the solar system to middle-schoolers in your community! Afterschool Universe (AU) is a 12-session out-of-school-time astronomy program that explores astronomy concepts through engaging hands-on activities. It introduces participants to the tools of astronomy and takes them on a journey through the universe beyond the solar system. Afterschool programs reach a very diverse population and are offered in a variety of settings where the students go when the school day is over. The afterschool community is looking for quality science programming that will engage the children. AU offers just such an opportunity to bring science and astronomy to this under-served population. The afterschool community all over the country has received this well-tested curriculum very enthusiastically. It recently passed the rigorous NASA Product Review with flying colors. Help us disseminate it far and wide by working with afterschool program providers in your community. AU is ideally run as a partnership between astronomers or EPO professionals and local afterschool program providers. The former contribute content expertise to help train the program leaders while the latter have a deep understanding of their target audience. This program addresses several IYA themes as it works with an audience that doesn't typically get much exposure to astronomy. The adult afterschool program leaders do not usually have science backgrounds and middle school students do not normally get to explore the topics in Afterschool Universe despite their interest in this content. Bring the universe down to earth by engaging adults and children in your community through an Afterschool Universe partnership!
Steif, Paul S.; Fu, Luoting; Kara, Levent Burak
2016-01-01
Problems faced by engineering students involve multiple pathways to solution. Students rarely receive effective formative feedback on handwritten homework. This paper examines the potential for computer-based formative assessment of student solutions to multipath engineering problems. In particular, an intelligent tutor approach is adopted and…
Institute of Scientific and Technical Information of China (English)
刘官厅; 范天佑
2003-01-01
The complex method of the plane elasticity in 2D quasicrystal with point group 10 mm tenfold rotational symmetry is established. First displacement potential function in the quasicrystal is represented by four analytic functions. Then by utilizing the properties of analytic function and through a great deal of derivation, the complex representations of stresses and displacements components of phonon fields and phason fields in the quasicrystal are given, which are the theoretical foundation for this method. From this theory, and by the help of conformal transformations in the theory of complex function, the problems of elliptic hole in the quasicrystal are solved. Its special cases are the solutions of well-known crack problem. Meanwhile, the results show that even if under the self-counterbalance force in the quasicrystal plane with elliptic hole, the stress components of phonon fields are also related to material constants of the quasicrystal when the phonon fields and phason fields are coupled, which is another distinctive difference from the properties of classical elastic theory. Besides, the present work is generalization and application of the complex method in the classical elastic theory established by Muskhelishvili to 2D quasicrystal. As in the classical elastic theory, if only conformal transformation from the quasicrystal plane to unit circle is found, any holey and crack problem in the quasicrystal plane could be solved.
Kester, Liesbeth; Kirschner, Paul A; van Merriënboer, Jeroen J G
2005-03-01
This study compared the effects of two information presentation formats on learning to solve problems in electrical circuits. In one condition, the split-source format, information relating to procedural aspects of the functioning of an electrical circuit was not integrated in a circuit diagram, while information in the integrated format condition was integrated in the circuit diagram. It was hypothesized that learners in the integrated format would achieve better test results than the learners in the split-source format. Equivalent-test problem and transfer-test problem performance were studied. Transfertest scores confirmed the hypothesis, though no differences were found on the equivalent-test scores.
Brodsky, Yu. I.
2015-01-01
The work is devoted to the application of Bourbaki's structure theory to substantiate the synthesis of simulation models of complex multicomponent systems, where every component may be a complex system itself. An application of the Bourbaki's structure theory offers a new approach to the design and computer implementation of simulation models of complex multicomponent systems—model synthesis and model-oriented programming. It differs from the traditional object-oriented approach. The central concept of this new approach and at the same time, the basic building block for the construction of more complex structures is the concept of models-components. A model-component endowed with a more complicated structure than, for example, the object in the object-oriented analysis. This structure provides to the model-component an independent behavior-the ability of standard responds to standard requests of its internal and external environment. At the same time, the computer implementation of model-component's behavior is invariant under the integration of models-components into complexes. This fact allows one firstly to construct fractal models of any complexity, and secondly to implement a computational process of such constructions uniformly-by a single universal program. In addition, the proposed paradigm allows one to exclude imperative programming and to generate computer code with a high degree of parallelism.
Bringing Pulsed Laser Welding into Production
DEFF Research Database (Denmark)
Olsen, Flemmming Ove
1996-01-01
activities concerning the weldability of high alloyed austenitic stainless steels for mass production industry applying industrial lasers for fine welding will be described. Studies on hot cracking sensitivity of high alloyed austenitic stainless steel applying both ND-YAG-lasers and CO2-lasers has been......In this paper, some research and develop-ment activities within pulsed laser welding technology at the Tech-nical University of Denmark will be described. The laser group at the Insti-tute for Manufacturing Technology has nearly 20 years of experience in laser materials process-ing. Inter......-nationally the group is mostly known for its contri-butions to the development of the laser cutting process, but further it has been active within laser welding, both in assisting industry in bringing laser welding into production in several cases and in performing fundamental R & D. In this paper some research...
Developing a web page: bringing clinics online.
Peterson, Ronnie; Berns, Susan
2004-01-01
Introducing clinical staff education, along with new policies and procedures, to over 50 different clinical sites can be a challenge. As any staff educator will confess, getting people to attend an educational inservice session can be difficult. Clinical staff request training, but no one has time to attend training sessions. Putting the training along with the policies and other information into "neat" concise packages via the computer and over the company's intranet was the way to go. However, how do you bring the clinics online when some of the clinical staff may still be reluctant to turn on their computers for anything other than to gather laboratory results? Developing an easy, fun, and accessible Web page was the answer. This article outlines the development of the first training Web page at the University of Wisconsin Medical Foundation, Madison, WI.
Coats, Abby Heckman; Blanchard-Fields, Fredda
2008-03-01
Young, middle-aged, and older adults' emotion regulation strategies in interpersonal problems were examined. Participants imagined themselves in anger- or sadness-eliciting situations with a close friend. Factor analyses of a new questionnaire supported a 4-factor model of emotion regulation strategies, including passivity, expressing emotions, seeking emotional information or support, and solving the problem. Results suggest that age differences in emotion regulation (such as older adults' increased endorsement of passive emotion regulation relative to young adults) are partially due to older adults' decreased ability to integrate emotion and cognition, increased prioritization of emotion regulation goals, and decreased tendency to express anger.
Institute of Scientific and Technical Information of China (English)
RenZePei; LiuJing; 等
1995-01-01
The application of BEM for solving normal or inverse bio-heat transfer problems of biological bodies with complex shapes is discussed and a new method for non-invasive reconstruction of the spatial temperature field and the non-homogeneous heat source is proposed in this paper,Tikhonov's (1979) regularization technique is used to improve the performance of ill-posed equations in the process of solving for inverse problems.The feasibility of the above mentioned method was verified by the numerical test results of a two-dimensional steady state problem.This method has laid the theoretical foundation for developing a bimedical instrument and respective software used in the non-invasive monitoring of the spatial temperature field of biological bodies.
Directory of Open Access Journals (Sweden)
Christopher W. Tindale
2009-04-01
Full Text Available La nécessité pour l’argumentateur de connaître son auditoire afin de persuader est l’un des lieux communs de la théorie de l’argumentation. Mais, en dehors du cas où l’argumentation s’adresse à soi-même ou à un interlocuteur unique, les auditoires vers lesquels nous nous tournons sont de composition complexe, et reflètent la diversité de nos identités et les différents groupes auxquels nous appartenons. Comment les argumentateurs doivent-ils faire face à une telle diversité de l’auditoire ? S’inspirant principalement des travaux de Perelman et Olbrechts-Tyteca, ainsi que de ceux d’Amartya Sen, cet article explore la manière dont divers aspects identitaires sont choisis par les auditoires, et les moyens par lesquels les argumentateurs peuvent encourager de tels choix en préalable à l’acte de persuasion lui-même.It is a commonplace of argumentation theory that an arguer needs to know her or his audience in order to be persuasive. But beyond arguments directed to oneself or to a single interlocutor, the audiences we address are complex in make-up, reflecting the diversity of our own identities and the different groups to which we belong. How should arguers accommodate such diversity within audiences? Drawing principally from the work of Perelman and Olbrechts-Tyteca, as well as Amartya Sen, this paper explores the ways aspects of identities are chosen by audiences, and how arguers can encourage such choices as a preliminary move to persuasion itself.
Balukovic, Jasmina; Slisko, Josip; Hadzibegovic, Zalkida
2011-01-01
Since 2003, international project PISA evaluates 15-year old students in solving problems that include "decision taking", "analysis and design of systems" and "trouble-shooting". This article presents the results of a pilot research conducted with 215 students from first to fourth grade of a high school in Sarajevo…
Nguyen, Thu Suong Thi; Scribner, Samantha M. Paredes; Crow, Gary M.
2012-01-01
The case of Allen Elementary School presents tangled narratives and wicked problems describing the multidimensionality of school community work. Using multiple converging and diverging vignettes, the case points to the distinctiveness of individual experience in schools; the ways institutionalized organizational narratives become cultural…
Kester, Liesbeth; Kirschner, Paul A.; Van Merriënboer, Jeroen
2007-01-01
This study compared the effects of two information presentation formats on learning to solve problems in electrical circuits. In one condition, the split-source format, information relating to procedural aspects of the functioning of an electrical circuit was not integrated in a circuit diagram, whi
Hartmann, Alexander K
2005-01-01
A concise, comprehensive introduction to the topic of statistical physics of combinatorial optimization, bringing together theoretical concepts and algorithms from computer science with analytical methods from physics. The result bridges the gap between statistical physics and combinatorial optimization, investigating problems taken from theoretical computing, such as the vertex-cover problem, with the concepts and methods of theoretical physics. The authors cover rapid developments and analytical methods that are both extremely complex and spread by word-of-mouth, providing all the necessary
Franceschet, Massimo
2014-01-01
Complex systems and their underlying convoluted networks are ubiquitous, all we need is an eye for them. They pose problems of organized complexity which cannot be approached with a reductionist method. Complexity science and its emergent sister network science both come to grips with the inherent complexity of complex systems with an holistic strategy. The relevance of complexity, however, transcends the sciences. Complex systems and networks are the focal point of a philosophical, cultural ...
Energy Technology Data Exchange (ETDEWEB)
Castro, Paulo Alexandre de; Souza, Thaianne Lopes de [Universidade Federal de Goias (UFG), Catalao, GO (Brazil)
2011-07-01
Full text. What the Brazilian soccer championship, Hollywood actors, the network of the Internet, the spread of viruses and electric distribution network have in common? Until less than two decade ago, the answer would be 'nothing' or 'almost nothing'. However, the answer today to this same question is 'all' or 'almost all'. The answer to these questions and more can be found through a sub-area of statistical physics | called science of complex networks that has been used to approach and study the most diverse natural and non-natural systems, such as systems/social networks, information, technological or biological. In this work we study the distribution network of electric power in Brazil (DEEB), from a perspective of complex networks, where we associate stations and/or substations with a network of vertices and the links between the vertices we associate with the transmission lines. We are doing too a comparative study with the best-known models of complex networks, such as Erdoes-Renyi, Configuration Model and Barabasi-Albert, and then we compare with results obtained in real electrical distribution networks. Based on this information, we do a comparative analysis using the following variables: connectivity distribution, diameter, clustering coefficient, which are frequently used in studies of complex networks. We emphasize that the main objective of this study is to analyze the robustness of the network DEEB, and then propose alternatives for network connectivity, which may contribute to the increase of robustness in maintenance projects and/or expansion of the network, in other words our goal is to make the network to proof the blackouts or improve the endurance the network against the blackouts. For this purpose, we use information from the structural properties of networks, computer modeling and simulation. (author)
Mathematical Analysis of Evolution, Information, and Complexity
Arendt, Wolfgang
2009-01-01
Mathematical Analysis of Evolution, Information, and Complexity deals with the analysis of evolution, information and complexity. The time evolution of systems or processes is a central question in science, this text covers a broad range of problems including diffusion processes, neuronal networks, quantum theory and cosmology. Bringing together a wide collection of research in mathematics, information theory, physics and other scientific and technical areas, this new title offers elementary and thus easily accessible introductions to the various fields of research addressed in the book.
Bringing Reflections into the TEFL Classrooms
Directory of Open Access Journals (Sweden)
M Sri Samiati Tarjana
2002-01-01
Full Text Available Abstract: Reflective practice is defined by John Dewey as a proactive, ongoing examination of beliefs and practices, their origins and impacts. In the reflective practice, the teacher and learners are engaged in a continuous cycle of self-observation and self-evaluation in order to understand their own actions and reactions, and thereby develop the teaching-learning process on an on-going basis. While English is regarded as compulsory in the preparation of more qualified human resources for the country, there are still complaints about the low English mastery of the majority of secondary and tertiary education graduates in Indonesia. It seems likely that bringing the reflective practice in the TEFL classrooms will help improve the teaching-learning of English in a more caring and responsive manner. It is expected that this will not only improve the English mastery, but also develop personal talents and capacities of the learners. The features of reflective practice in TEFL and their advantages for personal and professional development will be further discussed.
Bringing Technology into High School Physics Classrooms
Zettili, Nouredine
2005-04-01
In an effort to help high school physics teachers bring technology into their classrooms, we at JSU have been offering professional development to secondary education teachers. This effort is part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), a No-Child Left Behind (NCLB) grant funded by the Alabama Commission on Higher Education, serving high school physics teachers in Northeast Alabama. This project is motivated by a major pressing local need: A large number of high school physics teachers teach out of field. To achieve IMPACTSEED's goals, we have forged a functional collaboration with school districts from about ten counties. This collaboration is aimed at achieving a double aim: (a) to make physics and chemistry understandable and fun to learn within a hands-on, inquiry-based setting; (b) to overcome the fear- factor for physics and chemistry among students. Through a two-week long summer institute, a series of weekend technology workshops, and onsite support, we have been providing year-round support to the physics/chemistry teachers in this area. This outreach initiative has helped provide our students with a physics/chemistry education that enjoys a great deal of continuity and consistency from high school to college.
Bringing science to the policy table
2014-01-01
“They shall beat their swords into plowshares, and their spears into pruning hooks. Nation shall not lift up sword against nation. Neither shall they learn war anymore." So says Isaiah 2:4, as transcribed on the famous wall in Ralph Bunche park, just the other side of 1st Avenue from the UN’s New York headquarters, where we held a celebration of our 60th anniversary year on Monday 20 October. I used the quotation in my opening address, since it is such a perfect fit to the theme of 60 years of science for peace and development. The event was organised with the United Nations Economic and Social Council, ECOSOC, in the framework of CERN’s observer status at the UN, and although focused on CERN, its aim was broader. Presentations used CERN as an example to bring out the vital importance of science in general to the themes of peace and development. The event was presided over by Martin Sajdik, President of ECOSOC, and we were privileged to have presentat...
Poster power brings together electronics community
2006-01-01
An 'Electronics at CERN' poster session was displayed on the mezzanine in building 500 for two days from 30 November. The display consisted of 20 posters and brought together a wide range of electronic projects designed and assembled by CERN teams and other collaborators involved in the building of the LHC. This was the first time this event had been held. As its organiser John Evans (IT/DES) explained, 'the idea came from the experience of attending conferences outside CERN, where you may find projects from CERN you didn't know about. It's nice to bring them together so we can all benefit from the efforts made.' The work on show spanned different departments and experiments, ranging from microelectronics to equipment designed for giant magnets. The invited audience was equally broad and included engineers, physicists as well as the electronics community at CERN. An informal gathering of all the exhibitors also offered an opportunity to view and discuss the work over a cup of coffee. 'The poster session acts...
Directory of Open Access Journals (Sweden)
Terent'eva Elena Olegovna
2013-09-01
Full Text Available Inner and outer Lamb problems are of extreme importance for various applications in geophysics, as these problems are often used for simulation of wave fields accompanying earthquakes. Solutions of the outer Lamb problem of concentrated force impact applied to the free surface of an elastic half-plane are analyzed in this article. Two solutions are compared: the analytical solution obtained in 1984 and the solution obtained in a modern FEM complex Abaqus.
Terent'eva Elena Olegovna
2013-01-01
Inner and outer Lamb problems are of extreme importance for various applications in geophysics, as these problems are often used for simulation of wave fields accompanying earthquakes. Solutions of the outer Lamb problem of concentrated force impact applied to the free surface of an elastic half-plane are analyzed in this article. Two solutions are compared: the analytical solution obtained in 1984 and the solution obtained in a modern FEM complex Abaqus.
Schoenauer, W.; Daeubler, H. G.; Glotz, G.; Gruening, J.
1986-01-01
An implicit difference procedure for the solution of equations for a chemically reacting hypersonic boundary layer is described. Difference forms of arbitrary error order in the x and y coordinate plane were used to derive estimates for discretization error. Computational complexity and time were minimized by the use of this difference method and the iteration of the nonlinear boundary layer equations was regulated by discretization error. Velocity and temperature profiles are presented for Mach 20.14 and Mach 18.5; variables are velocity profiles, temperature profiles, mass flow factor, Stanton number, and friction drag coefficient; three figures include numeric data.
TQM brings collaboration to patient transport process.
Houston, K L; Clute, C; Ryan-Crepin, K; Kimball, M; Matthews, R
1994-10-01
Total quality management (TQM) principles can be utilized to achieve successful outcomes of an interdepartmental problem-solving process prior to implementation of a TQM formal structure within an organization. Prior to implementation of the new process, patient transport time from nursing units to lab destination was calculated at 17.6 minutes; postimplementation, an institutional benchmark of 15.4 minutes has been set. The mechanisms utilized for development, implementation, and evaluation of a process improvement team is the focus of the article. The reader will be taken on a journey through an interdepartmental problem-solving process utilizing the TQM principles.
Canfora, Fabrizio
2016-10-01
I analyze the quantum mechanical scattering off a topological defect (such as a Dirac monopole) as well as a Yukawa-like potential(s) representing the typical effects of strong interactions. This system, due to the presence of a short-range potential, can be analyzed using the powerful technique of the complex angular momenta which, so far, has not been employed in the presence of monopoles (nor of other topological solitons). Due to the fact that spatial spherical symmetry is achieved only up to internal rotations, the partial wave expansion becomes very similar to the Jacob-Wick helicity amplitudes for particles with spin. However, since the angular-momentum operator has an extra "internal" contribution, fixed cuts in the complex angular momentum plane appear. Correspondingly, the background integral in the Regge formula does not decrease for large values of |cos θ | (namely, large values of the Mandelstam variable s ). Hence, the experimental observation of this kind of behavior could be a direct signal of nontrivial topological structures in strong interactions. The possible relations of these results with the soft Pomeron are shortly analyzed.
Canfora, Fabrizio
2016-01-01
It is analyzed the quantum mechanical scattering off a topological defect (such as a Dirac monopole) as well as a Yukawa-like potential(s) representing the typical effects of strong interactions. This system, due to the presence of a short-range potential, can be analyzed using the powerful technique of the complex angular momenta which, so far, has not been employed in the presence of monopoles (nor of other topological solitons). Due to the fact that spatial spherical symmetry is achieved only up to internal rotations, the partial wave expansion becomes very similar to the Jacob-Wick helicity amplitudes for particles with spin. However, since the angular-momentum operator has an extra "internal" contribution, fixed cuts in the complex angular momentum plane appear. Correspondingly, the background integral in the Regge formula does not decrease for large values of cos(Theta) (namely, large values of the Mandelstam variable s). Hence, the experimental observation of this kind of behavior could be a direct sig...
Education Reform Brings New Challenges to Argentina.
Rossetti, Mercedes
1997-01-01
A description of recent changes in Argentina's system of education looks at underlying policy, the redesigned schooling system, emphasis placed on English language instruction, the teacher training system, and problems in the process for assuring an adequate flow of qualified English teachers. (MSE)
Bringing about Organisational Change--A Framework.
Stewart, J. D.
1989-01-01
Describes framework for organizational change based on propositions that change must be measurable and observable; organizational change requires individual change; and individual change requires learning and motivation to apply learning. Two models explained: a matrix indicating degrees of acceptance of problem and solution and continuum relating…
Bringing the Arts to the School Library
Moorefield-Lang, Heather
2011-01-01
The arts have their place in every facet of a school, and the library is no exception. Thinking beyond traditional definitions, arts education could include teaching creative problem solving as well as continuous questioning of issues and ideas. The media center is the perfect venue to showcase students' efforts in the arts. This article gives…
Bringing Knowledge Management into an Engineering Curriculum
Winberg, S. L.; Schach, S. R.; Inggs, M. R.
2007-01-01
The use of effective knowledge management is becoming an essential part of technical development projects in order to enable developers to handle the growing complexity of these projects. In this article we discuss an innovative approach to address this concern from the perspective of an undergraduate engineering curriculum. Instead of adding…
K-复调和函数的Schwarz边值问题%Schwarz's boundary value problem for K- complex harmonic function
Institute of Scientific and Technical Information of China (English)
张建元; 刘俊; 张毅敏; 张昕
2012-01-01
In the paper,the Schwarz's type mixed K- integral is defined and studied within elliptic domain B(0, R) (k): | z(k) | ≤R to obtain the solutions of Schwarz's boundary value problem within K-complex harmonic function. The conclusion is the continuation and application of the solution K- complex harmonic function with the corresponding theories of the analytic function and harmonic function.%在椭圆域B(0,R)(k)={z:｜z(k)｜≤R}上定义和讨论了Schwarz混合型K-积分,并用它来求K-复调和函数类H(D(k))中的Schwarz边值问题的解.所得结论包含了前人的有关结果.
Energy Technology Data Exchange (ETDEWEB)
Makarov, V A; Petnikova, V M; Potravkin, N N; Shuvalov, V V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)
2014-02-28
Using the linearization method, we obtain approximate solutions to a one-dimensional nonintegrable problem of propagation of elliptically polarised light waves in an isotropic gyrotropic medium with local and nonlocal components of the Kerr nonlinearity and group-velocity dispersion. The consistent evolution of two orthogonal circularly polarised components of the field is described analytically in the case when their phases vary linearly during propagation. The conditions are determined for the excitation of waves with a regular and 'chaotic' change in the polarisation state. The character of the corresponding nonlinear solutions, i.e., periodic analogues of multisoliton complexes, is analysed. (nonlinear optical phenomena)
Kovalevsky, L
2016-01-01
The Variational Theory of Complex Rays (VTCR) is an indirect Trefftz method designed to study systems governed by Helmholtz-like equations. It uses wave functions to represent the solution inside elements, which reduces the dispersion error compared to classical polynomial approaches but the resulting system is prone to be ill conditioned. This paper gives a simple and original presentation of the VTCR using the discontinuous Galerkin framework and it traces back the ill-conditioning to the accumulation of eigenvalues near zero for the formulation written in terms of wave amplitude. The core of this paper presents an efficient solving strategy that overcomes this issue. The key element is the construction of a search subspace where the condition number is controlled at the cost of a limited decrease of attainable precision. An augmented LSQR solver is then proposed to solve efficiently and accurately the complete system. The approach is successfully applied to different examples.
Bringing University Pedagogical Approach into Companies
DEFF Research Database (Denmark)
Kofoed, Lise B.; S. Stachowicz, Marian
2013-01-01
This paper describes and discusses how the university pedagogical approach used in engineering education can be applied in a corporate setting. Problem Based and Project Organised Learning (PBL) pedagogical approach has been used in engineering education at Aalborg University for 30 years...... and this PBL structure was implemented in a Danish company which wanted to establish a learning environment, so that their employees would share their knowledge and understanding of the work processes across different departments. The pedagogical approach is described and two workshops are used as examples...... of the learning processes. Through facilitated workshops focusing on problem analysis and the development of solutions, the participants gained a greater understanding of the need for learning, as well as increased motivation for sharing experiences across organisational boundaries. All participants made...
Bold move brings hope for children's services.
Moghal, Nadeem
2014-09-05
Employees may not always give or achieve their best but a "one cure fits all" approach will not solve the problem. Knowing how to motivate, value and energise staff is key to successful management and retention. Sharon Crabtree looks at the different factors that can affect staff motivation and explores how to recognize why individual staff may not be achieving or trying to achieve their full potential.
Community Efforts Bringing Research on Learning to the Geosciences
Manduca, C. A.; Mogk, D. W.; Kastens, K. A.
2009-12-01
Individual, departmental and community efforts have all played a major role in developing a thriving research effort addressing thinking and learning in the geosciences. Community efforts have been effective in elevating the importance of the field, defining a research agenda, fostering collaborations with cognitive science and education communities, building capacity within the geosciences, and developing reviewer awareness of the importance and opportunities within geoscience education research. Important community efforts include a call for geoscience education research in the 1997 NSF report Geoscience Education: A Recommended Strategy and in the subsequent 2000 NSF report ‘Bridges: Connecting Research and Education in the Earth System Sciences’. A research agenda and supporting recommendations for collaboration and capacity building were jointly developed by geoscience educators, cognitive scientists and education researchers at the 2002 NSF/Johnson Foundation funded workshop Bringing Research on Learning to the Geosciences. This research agenda emphasized studies of geoscience expertise, learning pathways (and their challenges) that are critical to the development of that expertise, and materials and environments that support this learning, with a focus on learning in the field and from large data sets, complex systems and deep time, spatial skills, and the synthesis of understanding from multiple sources of incomplete data. Collaboration and capacity building have been further supported by the NAGT sponsored professional development program “On the Cutting Edge” with workshops bringing together cognitive scientists, educators and geoscientists on topics including developing on-line learning resources, teaching with visualizations, the role of the affective domain in geoscience learning, teaching metacognition, and teaching with data. 40 successful educational research proposals are attributed to participation in On the Cutting Edge. An NSF funded
Directory of Open Access Journals (Sweden)
Gulia Fagimovna Galiullina
2014-05-01
Full Text Available The article examines the conditions of attracting the potential private business investments to a defense industry to enhance the country's defense and national security on the basis of the following argument: "business wins if the state wins". It is suggested to supplement the existing forms of cooperation between the state and business such as a government contact and privatization in the defense industry by the mechanism of a Public-Private Partnership (PPP, which is based on cooperation and risks sharing between the state and business. Implementation of PPP projects in Russia is slowed by the lack of basic federal law in PPPs field (adopted by the State Duma of Russian Federation Federal Assembly in the first reading and the corresponding legal act of the PPP in the defense industry (a federal law project is being considered . Their adoption and incorporation in the country's legislation will ensure legal and regulatory framework for PPPs in the defense industry. In addition to imperfect legislation there are a number of economic, administrative, legal and political constraints. Solving these problems will allow to either effectively develop priority areas of the defense industry , or support defense enterprises in the restructuring of their economic activity within the PPP projects realization.Objective: to substantiate the need for a public-private partnership mechanism.Subject of study: relevance and conditions for the implementation of PPP projects in the defense industry of Russia.Result: On the basis of the legal framework, the current situation analysis in the defense industry the role of public-private partnerships is justified and the current restrictions of PPP projects implementation in this area in terms of economics, management, law and policy are systematized.DOI: http://dx.doi.org/10.12731/2218-7405-2014-3-4
Bringing molecules back into molecular evolution.
Directory of Open Access Journals (Sweden)
Claus O Wilke
Full Text Available Much molecular-evolution research is concerned with sequence analysis. Yet these sequences represent real, three-dimensional molecules with complex structure and function. Here I highlight a growing trend in the field to incorporate molecular structure and function into computational molecular-evolution work. I consider three focus areas: reconstruction and analysis of past evolutionary events, such as phylogenetic inference or methods to infer selection pressures; development of toy models and simulations to identify fundamental principles of molecular evolution; and atom-level, highly realistic computational modeling of molecular structure and function aimed at making predictions about possible future evolutionary events.
Directory of Open Access Journals (Sweden)
Samuel eGreiff
2015-07-01
Full Text Available Scientists have studied the development of the human mind for decades and have accumulated an impressive number of empirical studies that have provided ample support for the notion that early cognitive performance during infancy and childhood is an important predictor of later cognitive performance during adulthood. As children move from childhood into adolescence, their mental development increasingly involves higher-order cognitive skills that are crucial for successful planning, decision-making, and problem solving. Importantly, few studies have employed higher-order thinking skills such as Complex Problem Solving (CPS as developmental outcomes in adolescents. To fill this gap, we tested a longitudinal developmental model in a sample of 2,021 Finnish sixth grade students (M = 12.41 years, SD = 0.52; 1,041 female, 978 male, 2 missing sex. We assessed working memory and fluid reasoning at age 12 as predictors of two CPS dimensions: knowledge acquisition and knowledge application. We further assessed students’ CPS performance 3 years later as a developmental outcome (N= 1696; M = 15.22 years, SD = 0.43; 867 female, 829 male. Missing data partly occurred due to dropout and technical problems during the first days of testing and varied across indicators and time with a mean of 27.2%. Results revealed that fluid reasoning was a strong predictor of both CPS dimensions, whereas working memory exhibited only a small influence on one of the two CPS dimensions. These results provide strong support for the view that CPS involves fluid reasoning and, to a lesser extent, working memory in childhood, and from there evolves into an increasingly complex structure of higher-order cognitive skills in adolescence.
Greiff, Samuel; Wüstenberg, Sascha; Goetz, Thomas; Vainikainen, Mari-Pauliina; Hautamäki, Jarkko; Bornstein, Marc H
2015-01-01
Scientists have studied the development of the human mind for decades and have accumulated an impressive number of empirical studies that have provided ample support for the notion that early cognitive performance during infancy and childhood is an important predictor of later cognitive performance during adulthood. As children move from childhood into adolescence, their mental development increasingly involves higher-order cognitive skills that are crucial for successful planning, decision-making, and problem solving skills. However, few studies have employed higher-order thinking skills such as complex problem solving (CPS) as developmental outcomes in adolescents. To fill this gap, we tested a longitudinal developmental model in a sample of 2,021 Finnish sixth grade students (M = 12.41 years, SD = 0.52; 1,041 female, 978 male, 2 missing sex). We assessed working memory (WM) and fluid reasoning (FR) at age 12 as predictors of two CPS dimensions: knowledge acquisition and knowledge application. We further assessed students' CPS performance 3 years later as a developmental outcome (N = 1696; M = 15.22 years, SD = 0.43; 867 female, 829 male). Missing data partly occurred due to dropout and technical problems during the first days of testing and varied across indicators and time with a mean of 27.2%. Results revealed that FR was a strong predictor of both CPS dimensions, whereas WM exhibited only a small influence on one of the two CPS dimensions. These results provide strong support for the view that CPS involves FR and, to a lesser extent, WM in childhood and from there evolves into an increasingly complex structure of higher-order cognitive skills in adolescence.
简单规则下Vote Control问题的复杂性分析%The complexity of Vote Control problem under simple rules
Institute of Scientific and Technical Information of China (English)
秦勤; 王雪瑞; 李建
2013-01-01
Given a set of candidatesC, a profile of partial votesV = (v1 ,v2 ,… ,vn) , and a distinguished candidate c ∈ C, is there a subset V' ,|V'|≤ k such that c ∈ r( V\\V '). The complexity of this problem is different under different scoring rules. The vote control problem was proved under Reto rule can be solved in polynomial time based on plurality rule, the NP - Complete proof of vote control problem underk' - approval rule was also obtained.%给定候选人集合C,投票集合V=(v1,v2,…,vn)和候选人c∈C,是否存在V的子集V',|V'|≤k,使得c∈r(V\\V’).该问题在不同的得分规则下复杂性是不同的.在plurality规则的基础上证明了Reto规则下Vote Control问题是多项式时间可解的,并给出了k'-approval规则下该问题是NP-Complete的证明.
Work-Based Courses: Bringing College to the Production Line
Kobes, Deborah; Girardi, Amy
2016-01-01
Work-based courses are an innovative way to bring college to the production line by using the job as a learning lab. This toolkit provides guidance to community college administrators and faculty who are interested in bringing a work-based course model to their college. It contains video content and teaching tips that introduce the six steps of…
Defining life or bringing biology to life.
Ruiz-Mirazo, Kepa; Peretó, Juli; Moreno, Alvaro
2010-04-01
In the present, post-genomic times, systemic or holistic approaches to living phenomena are compulsory to overcome the limits of traditional strategies, such as the methodological reductionism of molecular biology. In this paper, we propose that theoretical and philosophical efforts to define life also contribute to those integrative approaches, providing a global theoretical framework that may help to deal with or interpret the huge amount of data being collected by current high-throughput technologies, in this so-called 'omics' revolution. We claim that two fundamental notions can capture the core of the living, (basic) autonomy and open-ended evolution, and that only the complementary combination of these two theoretical constructs offers an adequate solution to the problem of defining the nature of life in specific enough-but also encompassing enough-terms. This tentative solution should also illuminate, in its most elementary version, the leading steps towards living beings on Earth.
2005-01-01
Tech-X Corporation releases simulation code for solving complex problems in plasma physics : VORPAL code provides a robust environment for simulating plasma processes in high-energy physics, IC fabrications and material processing applications
关于图划分中的一个计算复杂性问题%A Problem on the Computational Complexity of Graph Partitions
Institute of Scientific and Technical Information of China (English)
杨晓霖; 黄元秋
2005-01-01
一个稳定集是一个图的相互不相邻的顶点集,一个仙人掌图是一个任意两个圈都没有公共点的连通图.本文我们考虑如下问题,称之为STABLE CACTUS-问题的计算复杂性:给定一个图G,G中是否存在稳定集S使得G-S是一个仙人掌图.我们证明了STABLE CACTUS-问题是一个NP-完全问题,甚至可以进一步限制给定的图G是最大度不超过4的偶图.这个结果在图的度条件下是最好的了,我们利用图的最大亏格研究中的Xoung-树方法,证明了如果G是一个最大度不超过3的图,则STABLE CACTUS-问题是多项式时间可解的.%A stable set of a graph was a subset of pairwise non - adjacent vertices. A cactus was a connected graph whose any two circuits are vertex- disjoint. The computational complexity of the following problem, called STABLE CACTUS problem was discassed:Given a graph G, whether G had a stable set S such that G - S was a cactus? That the STABLE CACTUS problem was NP- complete even for a bipartite graph with maximum degree 4 was proved. The result was best possible in terms of the degree condition, for applying Xoung- tree method used in the study of maximum genus of graphs,also the STABLE CACTUS problem was solvable in polynomialtime for any graph with maximum degree
Bringing ayahuasca to the clinical research laboratory.
Riba, Jordi; Barbanoj, Manel J
2005-06-01
Since the winter of 1999, the authors and their research team have been conducting clinical studies involving the administration of ayahuasca to healthy volunteers. The rationale for conducting this kind of research is twofold. First, the growing interest of many individuals for traditional indigenous practices involving the ingestion of natural psychotropic drugs such as ayahuasca demands the systematic study of their pharmacological profiles in the target species, i.e., human beings. The complex nature of ayahuasca brews combining a large number of pharmacologically active compounds requires that research be carried out to establish the safety and overall pharmacological profile of these products. Second, the authors believe that the study of psychedelics in general calls for renewed attention. Although the molecular and electrophysiological level effects of these drugs are relatively well characterized, current knowledge of the mechanisms by which these compounds modify the higher order cognitive processes in the way they do is still incomplete, to say the least. The present article describes the development of the research effort carried out at the Autonomous University of Barcelona, commenting on several methodological aspects and reviewing the basic clinical findings. It also describes the research currently underway in our laboratory, and briefly comments on two new studies we plan to undertake in order to further our knowledge of the pharmacology of ayahuasca.
Scharcanski, Jacob
2016-01-01
Bringing computer vision into our daily life has been challenging researchers in industry and in academia over the past decades. However, the continuous development of cameras and computing systems turned computer vision-based measurements into a viable option, allowing new solutions to known problems. In this context, computer vision is a generic tool that can be used to measure and monitor phenomena in wide range of fields. The idea of using vision-based measurements is appealing, since the...
Simulation Apps Bring Us Closer to Mars
Knox, Jim
2015-01-01
My work with mathematical modeling and computer simulations began in earnest in 1987 when I signed on with the National Aeronautics and Space Administration, better known as NASA. At the time I was developing computer simulations to support the design of carbon dioxide (CO2) removal systems for the International Space Station (ISS) life support system. CO2 is a human metabolic waste, produced at a rate of a kilogram per day per crewmember. CO2 must be removed from the crew cabin, as it will quickly become detrimental to crew health. The systems used to remove CO2 are typically based on sorption processes, which include complex interactions of heat transfer, mass transfer, and gas flow through porous media. At this time, there were no commercial options for solving a set of coupled mathematical models such as partial differential equations (PDEs); you either force-fit the physics into a thermal analysis package or wrote your own code, complete with discretization, meshing, and solution algorithms. Unfortunately, coding CO2 removal processes from scratch did not allow an appropriate focus on the challenging yet crucial task of understanding and capturing the underlying physics via appropriate mathematical models. Configuration control was often simply ignored due to tight schedules, resulting in a code that would be quicker for a second party to rewrite than modify. In the early 2000s, I decided to move CO2 removal simulations to a platform with built-in meshing, solvers, and postprocessing capabilities, and that could solve user-defined multiphysics PDEs. The program chosen to meet these needs was COMSOL Multiphysics®. Along with freeing the engineer to focus on the underlying physics, a degree of configuration control was automatically achieved via a consistent user interface, thus allowing COMSOL users to share computer models. My team has developed simulations that are already providing a valuable debugging capability for the ISS CO2 removal system, and will
Institute of Scientific and Technical Information of China (English)
牛雁萍
2011-01-01
本文对带电粒子在复合场中的运动的典型试题进行了详尽分析，介绍了解题思路，旨在帮助学生掌握解题技巧。%This paper analyzes some typical problems on the motion of charged particle in complex field and introduces their problem-solving thoughts, hoping to help students grasp problem-solving skills.
Rouzaud, C.; Gatuingt, F.; Hervé, G.; Dorival, O.
2017-03-01
Frequency-based methods were set up in order to circumvent the limits of classical finite element methods in fast dynamic simulations due to discretizations. In this approach the dynamic loading was shifted in the frequency domain by FFT, then treated by the Variational Theory of Complex Rays, and then the time response was reconstructed through an IFFT. This strategy proved to be very efficient due to the CPU VTCR very low cost. However in the case of a large loading spectrum this frequency-by-frequency approach could seriously degrade the computational performances of the strategy. This paper addresses this point by proposing the use of Padé approximants in order to limit the number of frequencies at which the response should be calculated. Padé approximation is applied to the overall VTCR system based on its frequency dependency. Finally, as simulations on a simple academic case and on a civil engineering structure show, this method is found to be very efficient for interpolating the frequency response functions of a complex structure. This is a key point to preserve the efficiency of the complete VTCR strategy for transient dynamic problems.
Directory of Open Access Journals (Sweden)
Kamen Kotsilkov
2015-07-01
Full Text Available INTRODUCTION: The modern Periodontology has various approaches to achieve a complete functional and aesthetic rehabilitation of the mucogingival complex. These techniques include application of flaps with apical or coronal advancement in order to achieve different treatment objectives. Complex cases with different pathology on adjacent teeth require several surgeries thereby increasing treatment time and patient discomfort. New combined approaches are needed to meet the challenges of such cases. OBJECTIVE: This report presents a case with a simultaneous application of a resective and a mucogingival technique in one dental sextant. METHODS: I.C. (36 with a localized chronic periodontitis, Miller Class I gingival recessions (13,14 and subgingival caries lesions (15,16. A combined approach with simultaneous crown lengthening with apically positioned flap for 16,15 and root coverage with enamel matrix derivate and a coronally advanced flap for 14,13 was applied in order to avoid multiple surgical procedures. RESULTS: On the third month after the surgical procedure a complete root coverage (13,14 was achieved. The crown lengthening procedure enabled the restoration of the caries lesions and the placement of new crowns (15,16. The result at the third year demonstrates a stable gingival margin with no recurrence of the gingival recessions. CONCLUSION: The applied combined procedure led to a complete resolution of the existing problems with a single surgery. The simultaneous application of different procedures seems a promising approach aimed to reduce the treatment time and to diminish patient discomfort.
Bring your own device (BYOD) to work trend report
Hayes, Bob
2013-01-01
Bring Your Own Device (BYOD) to Work examines the emerging BYOD (Bring Your Own Device to work) trend in corporate IT. BYOD is the practice of employees bringing personally-owned mobile devices (e.g., smartphones, tablets, laptops) to the workplace, and using those devices to access company resources such as email, file servers, and databases. BYOD presents unique challenges in data privacy, confidentiality, security, productivity, and acceptable use that must be met proactively by information security professionals. This report provides solid background on the practice, original res
A complex analysis problem book
Alpay, Daniel
2016-01-01
This second edition presents a collection of exercises on the theory of analytic functions, including completed and detailed solutions. It introduces students to various applications and aspects of the theory of analytic functions not always touched on in a first course, while also addressing topics of interest to electrical engineering students (e.g., the realization of rational functions and its connections to the theory of linear systems and state space representations of such systems). It provides examples of important Hilbert spaces of analytic functions (in particular the Hardy space and the Fock space), and also includes a section reviewing essential aspects of topology, functional analysis and Lebesgue integration. Benefits of the 2nd edition Rational functions are now covered in a separate chapter. Further, the section on conformal mappings has been expanded.
Directory of Open Access Journals (Sweden)
Alejandro Cotes Torres
2005-12-01
Full Text Available El problema de la sostenibilidad es una temática que desde finales del siglo XX, ha venido preocupando cada vez mas a los diferentes sectores de la sociedad; pasando a ser uno de los temas de mayor interés para empresarios, consumidores, académicos e investigadores, que conforman las diferentes cadenas agroalimentarias del mundo. Este artículo presenta desde el punto de vista de la Teoría General de Sistemas, algunos elementos de reflexión critica, abordando la problemática de la sostenibilidad desde la complejidad de los sistemas de producción agropecuarios, partiendo desde la concepción filosófica original de la agricultura, hasta llegar a plantear algunas consideraciones que se deben tener en cuenta para el desarrollo de avances científicos y tecnológicos acordes con las necesidades de las cadenas agroalimentarias del siglo XXI; las cuales permiten orientar no solo el trabajo de los profesionales que lideran los procesos de producción animal y vegetal, sino que crea un sentido de pertenencia en todos los participantes de la cadena, resaltando la importancia de estudiar a través de un pensamiento sistémico, la Agronomía y la Zootecnia, como disciplinas que se aproximan a las complejidades de la Agricultura la cual es la piedra angular de la civilización, tal y como la conocemos actualmente.The problem of sustainability is a topic that since the end of the XX century has been worrying more the different sectors of society; becoming one of the topics of greatest interest for managers, consumers, academics and investigators that conform the different agricultural food chains of the world. This paper presents from the General Systems Theory point of view some elements of critical reflection, approaching the problem of sustainability from the complexity of agricultural production systems, beginning with the original philosophical conception of agriculture and ending by outlining some considerations that should be kept in mind for
Dubna at Play Exhibition Science Bringing Nations Together
1999-01-01
The small town of Dubna brings together the advantages of urban and country lifestyles. Dubna people spend a large part of their time outdoors taking part in all kind of sports or simply enjoying the beautiful surroundings.
Dubna at Play Exhibition Science Bringing Nations Together
1997-01-01
The small town of Dubna brings together the advantages of urban and country lifestyles. Dubna people spend a large part of their time outdoors taking part in all kind of sports or simply enjoying the beautiful surroundings.
What to bring to your labor and delivery
Prenatal care - what to bring ... underwear, and basic toiletries. While it is nice to have your own clothes with you, labor and ... very messy time, so you may not want to wear your brand-new lingerie. Items you should ...
Climate Change May Bring More Tainted Shellfish to Northern Seas
... page: https://medlineplus.gov/news/fullstory_160300.html Climate Change May Bring More Tainted Shellfish to Northern Seas ... must be monitored "in the light of ongoing climate change, especially in coastal areas most heavily affected by ...
Bringing critical realism to nursing practice: Roy Bhaskar's contribution.
Williams, Lynne; Rycroft-Malone, Jo; Burton, Christopher R
2017-04-01
In the context of modern nursing practice that is embedded within complex social situations, critical discussions about the contribution of major philosophers are relevant and important. Whilst nurse theorists have advanced and shaped nursing as a discipline, other major philosophers can offer much to advance nursing enquiry. In this paper, we focus on philosopher Roy Bhaskar who, amongst others, developed critical realism, a philosophy for social science which connects with how many of us think about the world. Bhaskar's work focuses our attention on the interplay between structure and agency and on the search for the causative or generative mechanisms that explain the social world. Bhaskar was interested in human emancipation, and we suggest his work is of great importance to advance understanding of complex social situations. Critical realism has already been endorsed by a range of disciplines, especially in research which focuses on real problems and acknowledges the complexities of the social world. In recent evidence from healthcare literature, there has been a surge in research using realist methodology (realist evaluation and realist synthesis), which is underpinned by the philosophy of critical realism and which offers a different perspective to understanding nursing and healthcare problems through the realist lens. However, we suggest that sufficient attention is not always paid to the philosophical roots of this methodology. In this paper, we provide insight into Bhaskar's work and demonstrate how research positioned within critical realism and realist methodology can advance nursing and healthcare-related knowledge. Through shining a light on Bhaskar, we illustrate how critical realism philosophy is a natural fit with human and health science enquiry, including nursing.
Directory of Open Access Journals (Sweden)
Joan Swart
2014-10-01
Full Text Available Mindfulness-based Mode Deactivation Therapy (MDT was conceptualized on the principles of cognitive theory for adolescents with behavioral problems and complex comorbid disorders. The theory and methodology addresses many of the shortcomings that were experienced in treating this population with available therapy approaches. As a systematic, manualized, and contextual treatment, MDT incorporates selected elements from approaches such as Cognitive Behavioral Therapy (CBT, Acceptance and Commitment Therapy (ACT, and Dialectical Behavior Therapy (DBT, together with the unique Validation-Clarification-Redirection (VCR change technique. Numerous empirical research studies have established MDT as an effective treatment for adolescents that consistently outperform alternative interventions. A cost-benefit analysis illustrates that MDT is also a cost-effective treatment, potentially saving between four and nine dollars in consequential behavioral costs for every dollar spent on the residential treatment of an adolescent. Therefore, there is ample evidence that Mode Deactivation Therapy (MDT is a third wave therapy with potential to become the preferred intervention for this population. The objective of this article is to present a condensed summary of this evidence, together with a brief overview of the concepts and principles that constitute the MDT theory and methodology.
Nagata, Keitaro; Nishimura, Jun; Shimasaki, Shinji
2016-07-01
Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a generalized Banks-Casher relation as we confirm explicitly.
Nagata, Keitaro; Shimasaki, Shinji
2016-01-01
Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a gene...
Institute of Scientific and Technical Information of China (English)
2011-01-01
At present, most of China’s railway hubs are developed to be transportation complexes, with some problems like unsmooth traffic circulation, mixed but disordered functions, separated spaces, etc. In high-speed rail era, high-speed railway hubs should be regarded as the catalyst to promoted urban development. The mode of urban complex should be developed, to closely connect the railway hub and the surrounding area within walking distance, so as people could get to their destinations in the most convenient way. Furthermore, it would strengthen people’s aggregation, thus to bring about larger scale urban development by the successful development of urban complex.
Fast and accurate analytical model to solve inverse problem in SHM using Lamb wave propagation
Poddar, Banibrata; Giurgiutiu, Victor
2016-04-01
Lamb wave propagation is at the center of attention of researchers for structural health monitoring of thin walled structures. This is due to the fact that Lamb wave modes are natural modes of wave propagation in these structures with long travel distances and without much attenuation. This brings the prospect of monitoring large structure with few sensors/actuators. However the problem of damage detection and identification is an "inverse problem" where we do not have the luxury to know the exact mathematical model of the system. On top of that the problem is more challenging due to the confounding factors of statistical variation of the material and geometric properties. Typically this problem may also be ill posed. Due to all these complexities the direct solution of the problem of damage detection and identification in SHM is impossible. Therefore an indirect method using the solution of the "forward problem" is popular for solving the "inverse problem". This requires a fast forward problem solver. Due to the complexities involved with the forward problem of scattering of Lamb waves from damages researchers rely primarily on numerical techniques such as FEM, BEM, etc. But these methods are slow and practically impossible to be used in structural health monitoring. We have developed a fast and accurate analytical forward problem solver for this purpose. This solver, CMEP (complex modes expansion and vector projection), can simulate scattering of Lamb waves from all types of damages in thin walled structures fast and accurately to assist the inverse problem solver.
Institute of Scientific and Technical Information of China (English)
李帮义
2002-01-01
This paper puts forward the concept of kth minimum spanning trees.For the special case k＝ 2, an polynomial algorithm is given, whose time com-plexity is O(rnn), where rn is the number of edges in the network, n is the num-ber of vertices. By using the fixed length spanning tree problem, it proves thatfinding the spanning tree length distributions problem is NP-C.
Bringing Model Checking Closer to Practical Software Engineering
AUTHOR|(CDS)2079681; Templon, J A; Willemse, T.A.C.
Software grows in size and complexity, making it increasingly challenging to ensure that it behaves correctly. This is especially true for distributed systems, where a multitude of components are running concurrently, making it dicult to anticipate all the possible behaviors emerging in the system as a whole. Certain design errors, such as deadlocks and race-conditions, can often go unnoticed when testing is the only form of verication employed in the software engineering life-cycle. Even when bugs are detected in a running software, revealing the root cause and reproducing the behavior can be time consuming (and even impossible), given the lack of control the engineer has over the execution of the concurrent components, as well as the number of possible scenarios that could have produced the problem. This is especially pronounced for large-scale distributed systems such as the Worldwide Large Hadron Collider Computing Grid. Formal verication methods oer more rigorous means of determining whether a system sat...
Does Satisfaction with Teaching Quality Factors Bring Conceptual Change?
Directory of Open Access Journals (Sweden)
Saifur Rehman Khan
2014-05-01
Full Text Available The purpose of this study is to explore classroom teaching quality factors that determine the satisfaction level and ultimately bring conceptual change among students. This study tests the theories of customer satisfaction in educational psychology research on a sample of 972 respondents. Overwhelmingly the results point out that male students were highly dissatisfied and have little impact on conceptual change whereas female students were reported significant level of satisfaction and conceptual change. In conclusion, detailed empirical analyses promote the theory of learning-satisfaction with classroom teaching bring conceptual change.
Causality problem in Economic Science
Directory of Open Access Journals (Sweden)
JOSÉ LUIS RETOLAZA
2007-12-01
Full Text Available The main point of the paper is the problem of the economy to be consider like a science in the most strict term of the concept. In the first step we are going to tackle a presentation about what we understand by science to subsequently present some of the fallacies which have bring certain scepticism about the scientific character of the investigation in economy, to know: 1 The differences between hard and weak sciences -physics and social; 2 The differences between paradigm, —positivist and phenomenological— 3 The differences between physic causalityand historic causality. In the second step we are going to talk about two fundamental problems which are questioned: 1 the confusion between ontology and gnoseology and, 2 the erroneous concept of causality that commonly is used. In the last step of the paper we are going over the recent models of «causal explanation» and we suggest the probabilistic casualty development next with a more elaborated models of causal explanation, like a way to conjugate the scientific severity with the possibility to tackle complex economic realities.
Directory of Open Access Journals (Sweden)
Samuel Greiff
2014-03-01
Full Text Available Since the 1960ies, when pioneering research on Item Response Theory (IRT was published, considerable progress has been made with regard to the psychometrical quality of psychological assessment tools. One recent development building upon IRT is the introduction of Cognitive Diagnostic Modeling (CDM. The major goal of introducing CDM was to develop methods that allow for examining which cognitive processes are involved when a person is working on a specific assessment task. More precisely, CDM enables researchers to investigate whether assumed task characteristics drive item difficulty and, thus, person ability parameters. This may – at least according to the assumption inherent in CDM - allow conclusions about cognitive processes involved in assessment tasks. In this study, out of the numerous CDMs available the Least Square Distance Method (LSDM; Dimitrov, 2012 was applied to investigate psychometrical qualities of an assessment instrument measuring Complex Problem Solving (CPS skills. For the purpose of the study, two task characteristics essential for mastering CPS tasks were identified ex-ante – degree of connectivity and presence of indirect effects by adding eigendynamics to the task. The study examined whether and how the two hypothesized task characteristics drive item difficulty of two CPS dimensions, knowledge acquisition and knowledge application. The sample consisted of 490 German high school students, who completed the computer-based CPS assessment instrument MicroDYN. The two task characteristics in MicroDYN items were varied systematically. Results obtained in LSDM indicated that the two hypothesized task characteristics, degree of connectivity and introducing indirect effects, drove item difficulty only for knowledge acquisition. Hence, other task characteristics that may determine item difficulty of knowledge application need to be investigated in future studies in order to provide a sound measurement of CPS.
复杂反应约束的流程优化调度问题及求解%Complex reaction process constraint scheduling problem and its solution
Institute of Scientific and Technical Information of China (English)
戴欣华; 王万良; 徐新黎
2011-01-01
The scheduling mathematical model of chemical production process becomes more difficult to establish, considering the effect of I complex chemical reaction. In this paper, on optimal problem of a small ammonia synthetic process is studied to build a scheduling mathematic; model, researching the synthesis effect of temperature, pressure and environmental factors of ammonia synthetic process. The schedulin mathematical model is optimized by multi-objective PSO method. And the results showed that the model has good convergence and stability.%由于化工流程的生产过程涉及复杂的化学反应，因此，在研究化工流程中的调度问题的时候需要考虑其化学反应所带来的影响因素；这就使得调度的数学模型的建立变得非常的困难。本文针对中小型合成氨流程中的调度问题进行研究，分析合成氨反应的温度、压力、环境等影响因素建立调度的数学模型，采用基于微粒群算法的多目标优化方法对该流程进行优化调度，其结果表明所建的模型具有很好的收敛性和稳定性。
Directory of Open Access Journals (Sweden)
J. A. Tenreiro Machado
2017-02-01
Full Text Available Complex systems (CS involve many elements that interact at different scales in time and space. The challenges in modeling CS led to the development of novel computational tools with applications in a wide range of scientific areas. The computational problems posed by CS exhibit intrinsic difficulties that are a major concern in Computational Complexity Theory. [...
Bringing Curriculum Theory and Didactics Together: A Deweyan Perspective
Deng, Zongyi
2016-01-01
Using Dewey's method of resolution for resolving a dualism exemplified in "The Child and the Curriculum," this article reconciles and brings together two rival schools of thought--curriculum theory and didactics--in China. The central thesis is that the rapprochement requires a reconceptualisation of curriculum theory and didactics in…
The Chemedian Brings Laughter to the Chemistry Classroom
Weitkamp, Emma; Burnet, Frank
2007-01-01
"The Chemedian and the Crazy Football Match" is a comic strip developed by the authors to bring humor to aspects of the UK primary science curriculum. The comic strip was tested in six English primary school classes (years 3-5; ages 7-10); over 150 children participated in the project, together with six teachers. Children found the comic strip fun…
Driven: Bringing German Auto Concepts to the Classroom
Adney, Cara
2012-01-01
A world away from the red dirt of Oklahoma, David Shields and Shelly Smith felt right at home. A national grant took the Meridian Technology Center automotive teachers on a trip to Germany that car lovers only dream about. The tour to the major automakers last summer has them geared up and bringing fresh ideas to the classroom. They spent four…
Bringing the LHC and ATLAS to a regional planetarium
Schwienhorst, Reinhard
2011-01-01
An outreach effort has started at Michigan State University to bring particle physics, the Large Hadron Collider, and the ATLAS experiment to a general audience at the Abrams planetarium on the MSU campus. A team of undergraduate students majoring in physics, communications arts & sciences, and journalism are putting together short clips about ATLAS and the LHC to be shown at the planetarium.
Bringing internet connectivity to rural Zambia using a collaborative approach
Matthee, K.W.; Mweemba, G.; Pais, A.V.; Starn, G.V.; Rijken, M.
2007-01-01
This paper presents an initiative to bring connectivity to rural Zambia using a collaborative approach. In particular, it focuses on a proof-of-concept Internet service that has been implemented in rural Macha located in the Southern Province of Zambia. The service operates using satellite terminals
"Bring Your Own Device": Considering Potential Risks to Student Health
Merga, Margaret K.
2016-01-01
Background and context: Schools in Australia and internationally are increasingly adopting a Bring Your Own Device (BYOD) approach to teaching and learning. The review: While discussion of a BYOD approach has taken place, there is a dearth of consideration of the potential impact of BYOD policy on student health. Implementation of a BYOD policy…
Model Testing - Bringing the Ocean into the Laboratory
DEFF Research Database (Denmark)
Aage, Christian
2000-01-01
Hydrodynamic model testing, the principle of bringing the ocean into the laboratory to study the behaviour of the ocean itself and the response of man-made structures in the ocean in reduced scale, has been known for centuries. Due to an insufficient understanding of the physics involved, however...
Bring Your Own Device: Parental Guidance (PG) Suggested
Kiger, Derick; Herro, Dani
2015-01-01
Educators are incorporating students' mobile devices into the schooling experience via Bring Your Own Device (BYOD) initiatives. This is advantageous for many reasons, most notably, improving access to Internet resources and digital tools in support of teaching and learning. Obtaining parental support is key to BYOD success. Therefore, this study…
Excelsior: Bringing the Benefits of Modularisation to Excel
Paine, Jocelyn
2008-01-01
Excel lacks features for modular design. Had it such features, as do most programming languages, they would save time, avoid unneeded programming, make mistakes less likely, make code-control easier, help organisations adopt a uniform house style, and open business opportunities in buying and selling spreadsheet modules. I present Excelsior, a system for bringing these benefits to Excel.
Bringing New Ph.D.s Together for Interdisciplinary Climate Change Research
Phelan, Liam; Jones, Holly; Marlon, Jennifer R.
2013-01-01
Climate change is complex and thus requires interdisciplinary research, and new scholars are rising to that challenge. The Dissertations Initiative for the Advancement of Climate Change Research (DISCCRS (pronounced "discourse"); see http://www.disccrs.org) brings together select groups of recent PhD graduates to encourage interdisciplinary work on climate change. The DISCCRS Symposium VII held just outside of Colorado Springs, Colo., brought together 33 graduates from fields as diverse as climatology, ecology, anthropology, and political science for an intensive week of cross-disciplinary engagement in activities like facilitation and leadership training, collaborative research development, peer networking, communication training, and analysis of working group processes.
van Bommel, S.; Röling, N.; Aarts, N.; Turnhout, E.
2009-01-01
Social learning has been championed as a promising approach to address complex resource problems. According to theory, social learning requires several pre-conditions to be met, including (1) a divergence of interests, (2) mutual interdependence and (3) the ability to communicate. This article inves
Bommel, van S.; Roling, N.G.; Aarts, M.N.C.; Turnhout, E.
2009-01-01
Social learning has been championed as a promising approach to address complex resource problems. According to theory, social learning requires several pre-conditions to be met, including (1) a divergence of interests, (2) mutual interdependence and (3) the ability to communicate. This article inves
Casting a Wide Net for Innovation: Bringing Interdisciplinary Collaboration to Real World Problems
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Robert Cherinka
2014-08-01
Full Text Available Federal agencies are seeking new ways to innovate, procure and enhance enterprise capabilities. Competitions are one tool that federal agencies can use to drive innovation and solve mission-centric problems—whether technical, scientific, or creative. In this paper we present an examination of several approaches to foster open innovation through challenges and competitions in support of key business operations in the workforce. We highlight specific examples of their use in "real world" environments and provide an assessment of applicability, benefits and challenges for implementation in large organizations.
Swings of Science: From Complexity to Simplicity and Back
Pismen, L. M.
Science brings order into unfathomable complexity of nature, exposing its simple underlying laws. New insights and new means of observation bring about, however, new questions, and the world picture becomes more complex again, until simplified on a still deeper level of understanding. The swinging motion from complexity to simplicity and back can be discerned in the evolution of religions, in the search for basic elements, in cosmology. We will follow this motion in more detail taking as examples more specific problems of contemporary science: turbulence, pattern formation and biological morphogenesis. In all cases, simplicity achieved by discerning simplified laws and generic scenarios at the heart of complex phenomena is broken again as they are studied in minute detail. In our time, the swing moves with staggering speed toward ever increased complexity. This does not mean that the reductionist scientific paradigm is abandoned: even simple laws can engender complex phenomenology; metaphysical offshoots appear, however, on fringes of science. We do not know whether the swing will ever turn around toward simplicity again.
A Proposal for Measuring Interactivity that Brings Learning Effectiveness
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Tosh Yamamoto
2010-03-01
Full Text Available It is proposed in this paper that some type of way to measure and visualize interactivity in the multimedia or e-Learning contents is necessary in order to clearly identify interactivity that brings learning effectiveness. Interactivity during learning will arouse students’ intellectual curiosity and motivate them to learn further. Although the interaction in the communication between the teacher and his/her students in a regular classroom is ideal, it is not possible to maintain the equivalence in the multimedia or e-Learning contents. In order to rigorously formalize the field of measuring interactivity as a theory, theoretical constructs such as interactivity, interest, knowledge, and experience are redefined first. Then, the defined “interactivity” is broken down to subcomponents to develop an assessment tool for the interactivity which brings learning effectiveness. In the end, it is proved that the interactivity in learning can be measured.
Brun, Guillaume
The Optical Complex Systems are more and more in the heart of various systems that industrial applications bring to everyday life. From environment up to spatial applications, OCS is also relevant in monitoring, transportation, robotics, life sciences, sub-marine, and even for agricultural purposes.
Institute of Scientific and Technical Information of China (English)
黄沙; 闻国椿
2000-01-01
This paper deals with the Riemann-Hilbert boundary value problem for general nonlinear elliptic complex equations of second order. Firstly we propose the Riemann-Hilbert problem and its well posedness, and then we give the representation of solutions for the modified boundary value problem and prove its solvability, and finally derive solvability conditions of the original Riemann-Hilbert problem.%讨论了一般二阶非线性椭圆复方程的Riemann-Hilbert边值问题. 首先给出Riemann-Hilbert问题及其适应性的概念,其次给出改进后的边值问题解的表述并证明了它的可解性,最后导出原Riemann-Hilbert边值问题的可解条件.
Bringing History Home. Postcolonial Immigrants and the Dutch Cultural Arena
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S. Legêne
2011-01-01
Full Text Available Bringing History Home: Postcolonial Immigrants and the Dutch Cultural ArenaThree Dutch-language monographs published in 2008-2009 by Ulbe Bosma, Lizzy van Leeuwen and Gert Oostindie in the context of the interdisciplinary research programme Bringing History Home, present a history of identity politics in relation to ‘postcolonial immigrants’. This term refers to some 500,000 people who since 1945 arrived in the Netherlands from Indonesia and the former Dutch New Guinea, Suriname or the Antillean islands in the Caribbean. Bosma traces the development of postcolonial immigrant organizations. In interaction with government policies, these organizations moved from mere socioeconomic emancipation struggles to mere cultural identity politics. Van Leeuwen takes such cultural identity politics as the starting point for her analysis of Indo-Dutch and Dutch Indies cultural initiatives and the competing interests at stake in the Indies heritage discourse. Oostindie discusses these developments in terms of community development and change within Dutch society at large. He introduces the notion of a ‘postcolonial bonus’. In postcolonial Netherlands, this bonus was available to immigrants on the grounds of a shared colonial past. Today, this bonus is (almost spent. The review discusses the three monographs, as well as the coherence of Bringing History Home as a research programme. Legêne argues, that notwithstanding valuable research outcomes, the very category of postcolonial immigrants does not constitute a convincing category of analysis.
What event-related potentials (ERPs) bring to social neuroscience?
Ibanez, Agustin; Melloni, Margherita; Huepe, David; Helgiu, Elena; Rivera-Rei, Alvaro; Canales-Johnson, Andrés; Baker, Phil; Moya, Alvaro
2012-01-01
Social cognitive neuroscience is a recent interdisciplinary field that studies the neural basis of the social mind. Event-related potentials (ERPs) provide precise information about the time dynamics of the brain. In this study, we assess the role of ERPs in cognitive neuroscience, particularly in the emerging area of social neuroscience. First, we briefly introduce the technique of ERPs. Subsequently, we describe several ERP components (P1, N1, N170, vertex positive potential, early posterior negativity, N2, P2, P3, N400, N400-like, late positive complex, late positive potential, P600, error-related negativity, feedback error-related negativity, contingent negative variation, readiness potential, lateralized readiness potential, motor potential, re-afferent potential) that assess perceptual, cognitive, and motor processing. Then, we introduce ERP studies in social neuroscience on contextual effects on speech, emotional processing, empathy, and decision making. We provide an outline of ERPs' relevance and applications in the field of social cognitive neuroscience. We also introduce important methodological issues that extend classical ERP research, such as intracranial recordings (iERP) and source location in dense arrays and simultaneous functional magnetic resonance imaging recordings. Further, this review discusses possible caveats of the ERP question assessment on neuroanatomical areas, biophysical origin, and methodological problems, and their relevance to explanatory pluralism and multilevel, contextual, and situated approaches to social neuroscience.
Khawam, Edward; Fahed, Daoud
2012-01-01
The purpose of this presentation is first to describe the symptoms and problems encountered in cranial nerve palsies (CNP). The purpose is also to describe the different means of treatment during the observational preoperative period and their positive or negative impact on each of the symptoms and problems. Finally, we will present our way of handling these patients in their preoperative period: practical, inexpensive, and unsophisticated means that keep the patient comfortable and prevent the secondary untoward effects that can take place.
Kinsella, John J.
1970-01-01
Discussed are the nature of a mathematical problem, problem solving in the traditional and modern mathematics programs, problem solving and psychology, research related to problem solving, and teaching problem solving in algebra and geometry. (CT)
Research on Computational Complexity of Reverse Network 1-median Problem%网络1-重心反问题的计算复杂性研究
Institute of Scientific and Technical Information of China (English)
吴龙树; 曹飞龙
2011-01-01
在网络中顶点的权值可以改变的情况下,对哈明距离下以及l1模下1-重心问题的反问题进行研究.通过将哈明距离下网络1-重心问题的反问题归约为0-1背包问题,证明即使是在链式网络中,在哈明距离下该问题仍是NP困难的,并给出l1模下在一般网络中求解1-重心反问题的多项式时间算法.%This paper researches the reverse 1-median problem under the hamming distance and l1-norm in condition that the weights of vertices in a network can be changed. Under the hamming distance, by transforming this problem to a 0-1 knapsack problem, it proves that even in chain network, this problem is NP-hard. Underl1-norm, it presents a polynomial time algorithm to solve the problem in general network.
Bring Your Own Device - Providing Reliable Model of Data Access
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Stąpór Paweł
2016-10-01
Full Text Available The article presents a model of Bring Your Own Device (BYOD as a model network, which provides the user reliable access to network resources. BYOD is a model dynamically developing, which can be applied in many areas. Research network has been launched in order to carry out the test, in which as a service of BYOD model Work Folders service was used. This service allows the user to synchronize files between the device and the server. An access to the network is completed through the wireless communication by the 802.11n standard. Obtained results are shown and analyzed in this article.
BRINGING CIVILIZATION: SAVAGERY AND THE TAMING OF THE SAVAGE
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Nicholas D. Newman
2015-01-01
Full Text Available “See, the Conqu’ring Hero Comes” goes the famous chorus from Handel’s Judas Maccabeus, but how does the hero conquer? Achilles defeats his enemies through his extraordinary prowess in battle, Odysseus by using his wit, but some heroes must abandon the trappings of civilization in order to conquer. This paper examines two examples of such heroes from Germanic and Greco-Roman myth: Beowulf and Herakles. In the texts analyzed, these heroes not only set aside their civilized veneer, but must journey into the territory of the monster they wish to destroy and there use savagery to defeat the savage, in order to bring civilization.
Bringing Technology into college and High School Physics Classrooms
Zettili, Nouredine
2007-04-01
We want to present ideas on ways of bringing technology to college and high school physics classrooms. We focus in particular on our outreach initiative in supporting a number of school districts with ways to improve high school physics education. This initiative is part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), a No-Child Left Behind grant funded by the Alabama Commission on Higher Education. This project is motivated by a major local need: A large number of high school physics teachers teach out of field. IMPACTSEED aims at helping high school teachers learn and master the various physics topics required by the Alabama course of study. Teachers are offered year-round support through a rich variety of programs: a two-week long summer institute, a series of five technology workshops, and onsite year-round support. Through our hands-on approach, we have identified a number of ways of bringing technology into physics classrooms. A number of technology projects were assigned to the teachers so as to show their students how physics connects to the technological devices around us. IMPACTSEED aims at providing our students with a physics education that enjoys continuity and consistency from high school to college.
A Review of Bring Your Own Device on Security Issues
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Morufu Olalere
2015-04-01
Full Text Available Mobile computing has supplanted internet computing because of the proliferation of cloud-based applications and mobile devices (such as smartphones, palmtops, and tablets. As a result of this, workers bring their mobile devices to the workplace and use them for enterprise work. The policy of allowing the employees to work with their own personal mobile devices is called Bring Your Own Devices (BYOD. In this article, we discuss BYOD’s background, prevalence, benefits, challenges, and possible security attacks. We then review contributions of academic researchers on BYOD. The Universiti Putra Malaysia online databases (such as IEEE Xplore digital library, Elsevier, Springer, ACM digital library were used to search for peer-reviewed academic publications and other relevant publications on BYOD. The Google Scholar search engine was also used. Our thorough review shows that security issues comprise the most significant challenge confronting BYOD policy and that very little has been done to tackle this security challenge. It is our hope that this review will provide a theoretical background for future research and enable researchers to identify researchable areas of BYOD.
Teaching Computer Science through Problems, Not Solutions
Fee, Samuel B.; Holland-Minkley, Amanda M.
2010-01-01
Regardless of the course topic, every instructor in a computing field endeavors to engage their students in deep problem-solving and critical thinking. One of the specific learning outcomes throughout our computer science curriculum is the development of independent, capable problem solving--and we believe good pedagogy can bring such about. Our…
Hansen, Thomas Mejer; Cordua, Knud Skou; Looms, Majken Caroline; Mosegaard, Klaus
2013-03-01
We present an application of the SIPPI Matlab toolbox, to obtain a sample from the a posteriori probability density function for the classical tomographic inversion problem. We consider a number of different forward models, linear and non-linear, such as ray based forward models that rely on the high frequency approximation of the wave-equation and 'fat' ray based forward models relying on finite frequency theory. In order to sample the a posteriori probability density function we make use of both least squares based inversion, for linear Gaussian inverse problems, and the extended Metropolis sampler, for non-linear non-Gaussian inverse problems. To illustrate the applicability of the SIPPI toolbox to a tomographic field data set we use a cross-borehole traveltime data set from Arrenæs, Denmark. Both the computer code and the data are released in the public domain using open source and open data licenses. The code has been developed to facilitate inversion of 2D and 3D travel time tomographic data using a wide range of possible a priori models and choices of forward models.
Bringing authentic service learning to the classroom: benefits and lessons learned
Chamberlain, Leslie C.
2016-06-01
Project-based learning, which has gained significant attention within K-12 education, provides rich hands-on experiences for students. Bringing an element of service to the projects allow students to engage in a local or global community, providing an abundance of benefits to the students’ learning. For example, service projects build confidence, increase motivation, and exercise problem-solving and communication skills in addition to developing a deep understanding of content. I will present lessons I have learned through four years of providing service learning opportunities in my classroom. I share ideas for astronomy projects, tips for connecting and listening to a community, and helpful guidelines to hold students accountable in order to ensure a productive and educational project.
Next Challenges in Bringing Artificial Immune Systems to Production in Network Security
Hilker, Michael
2008-01-01
The human immune system protects the human body against various pathogens like e.g. biological viruses and bacteria. Artificial immune systems reuse the architecture, organization, and workflows of the human immune system for various problems in computer science. In the network security, the artificial immune system is used to secure a network and its nodes against intrusions like viruses, worms, and trojans. However, these approaches are far away from production where they are academic proof-of-concept implementations or use only a small part to protect against a certain intrusion. This article discusses the required steps to bring artificial immune systems into production in the network security domain. It furthermore figures out the challenges and provides the description and results of the prototype of an artificial immune system, which is SANA called.
Bringing inorganic chemistry to life with inspiration from R. J. P. Williams.
Hill, H Allen O; Sadler, Peter J
2016-03-01
Our appreciation of the scholarly ideas and thinking of Bob Williams is illustrated here by a few of the areas in which he inspired us. His journey to bring inorganic chemistry to life began with an early interest in analytical chemistry, rationalising the relative stabilities of metal coordination complexes (The Irving-Williams Series), and elucidating the organometallic redox chemistry of vitamin B12. He (and Vallee) recognised that metal ions are in energised (entatic) states in proteins and enzymes, which themselves are dynamic structures of rods and springs. He played a key role in helping Rosenberg to pave the road toward the clinic for the anticancer drug cisplatin. He believed that evolution is not just dependent on DNA, but also on the metallome. Organisms and the environment are one system: does DNA code directly for all the essential elements of life?
Research and Service Support: Bringing Users to Data
Delgado Blasco, Jose Manuel; Sabatino, Giovanni; Cuccu, Roberto; Rivolta, Giancarlo; Marchetti, Pier Giorgio
2016-08-01
The ESA Research and Service Support (RSS) service has the mission to support the Earth Observation (EO) data exploitation, by an operational pilot of the new paradigm "bring users to data" [1]. This approach fits well the challenges posed by larger data availability, from more missions, more frequently. It dramatically lowers the barriers to perform research activities, to develop algorithms and downstream services reducing the effort and resources needed by the EO users. This objective is achieved by (i) offering tools and services to the EO community granting a fast and easy data access (i.e. without the need to transfer the data into the scientist "own" infrastructure) and real (offered by RSS) scalable processing resources , and (ii) by supporting the researchers in developing new algorithms, enabling results visualization, verification, validation and sharing.
The Supernova Club: Bringing Space Science to Urban Youths
Sakimoto, P. J.; Pettit, R.; Balsara, D.; Garnavich, P.
2008-06-01
The Supernova Club is an experiment aimed at bringing space science to youths, almost all African Americans, from the most severely disadvantaged areas of the South Bend, Indiana, region. It leverages the National Youth Sports Program (NYSP) that, in Summer 2007, brought 100 children, ages 10-16 and living at or below the poverty level, to the Notre Dame campus for a 4-week non-residential summer program. Six contact hours of space science instruction were added to the core curriculum of nutrition, physical fitness, and academic study. At summer's end, 13 high interest/high potential youths were selected to form ``The Supernova Club''-a year-round, after-school, weekly follow-up program.
Institute of Scientific and Technical Information of China (English)
2016-01-01
2008年超音速离开之后，西雅图便没有了NBA球队，不过这座城市并没有就此放弃这个念头，他们一直在努力将一支NBA球队重新引入这座城市。作为西雅图人，快艇球员贾马尔·克劳福德饱含深情地发表了一篇名为《带超音速回来》（Bring Back The Sonics）的文章。他知道自己的家乡是一座非常热爱篮球的城市，西雅图球迷都希望在不远的将来看到一支新的超音速队。
Archaeopteryx: Bringing the Dino-Bird to Life
Energy Technology Data Exchange (ETDEWEB)
Bergmann, Uwe
2011-01-25
Some 150 million years ago, a strange creature died in a tropical lagoon that today is located in Bavaria, Germany. In 1861, a single feather of this creature was discovered. Not long afterward, a complete fossil was found with the same bird-like feathers but dinosaur-like anatomical features. Darwin had just published 'On the Origin of Species'; could this be the missing link that Darwin's supporters hoped to find? Recently, two of the now eleven discovered Archaeopteryx fossils, and that first feather, were brought to SLAC, where, using the intense X-ray beam, researchers searched for the chemical remains of the original living creatures. Please join us for this lecture, which will explain how the studies attempt to bring the original dino-bird back to life.
Bringing history to life: simulating landmark experiments in psychology.
Boynton, David M; Smith, Laurence D
2006-05-01
The course in history of psychology can be challenging for students, many of whom enter it with little background in history and faced with unfamiliar names and concepts. The sheer volume of material can encourage passive memorization unless efforts are made to increase student involvement. As part of a trend toward experiential history, historians of science have begun to supplement their lectures with demonstrations of classic physics experiments as a way to bring the history of science to life. Here, the authors report on computer simulations of five landmark experiments from early experimental psychology in the areas of reaction time, span of attention, and apparent motion. The simulations are designed not only to permit hands-on replication of historically important results but also to reproduce the experimental procedures closely enough that students can gain a feel for the nature of early research and the psychological processes being studied.
Directory of Open Access Journals (Sweden)
Cameron Richards
2015-06-01
Full Text Available The challenge of better reconciling individual and collective aspects of innovative problem-solving can be productively addressed to enhance the role of PBL as a key focus of the creative process in future higher education. This should involve ‘active learning’ approaches supported by related processes of teaching, assessment and curriculum. As Biggs & Tan (2011 have suggested, an integrated or systemic approach is needed for the most effective practice of outcomes-based education also especially relevant for addressing relatively simple as well as more complex problems. Such a model will be discussed in relation to the practical example of a Masters subject conceived with interdisciplinary implications, applications, and transferability: ‘sustainable policy studies in science, technology and innovation’. Different modes of PBL might be encouraged in terms of the authentic kinds of ‘complex problem-solving’ issues and challenges which increasingly confront an interdependent and changing world. PBL can be further optimized when projects or cases also involve contexts and examples of research and inquiry. However, perhaps the most crucial pillar is a model of portfolio assessment for linking and encouraging as well as distinguishing individual contributions to collaborative projects and activities.
Cogdell, Richard J; Köhler, Jürgen
2009-08-13
Optical single-molecule techniques can be used in two modes to investigate fundamental questions in biochemistry, namely single-molecule detection and single-molecule spectroscopy. This review provides an overview of how single-molecule spectroscopy can be used to gain detailed information on the electronic structure of purple bacterial antenna complexes and to draw conclusions about the underlying physical structure. This information can be used to understand the energy-transfer reactions that are responsible for the earliest reactions in photosynthesis.
A Feasibility Study of Implementing a Bring-Your-Own-Computing-Device Policy
2013-12-01
14. SUBJECT TERMS: Bring-your-own device ( BYOD ), hardware and software procurement plans, cost analysis, cloud...Full BYOC/ BYOD Policy for the GSBPP ....44 viii c. COA 3—Partial Secession of the Smart Classroom Construct...ACRONYMS AND ABBREVIATIONS AE academic edition BYOC bring your own computer BYOD bring your own device CA cost analysis CAL client access license
A multiscale problem in thermal science
Directory of Open Access Journals (Sweden)
Casenave Fabien
2013-01-01
Full Text Available We consider a multiscale heat problem in civil aviation: determine the temperature field in a plane in flying conditions, with air conditioning. Ventilated electronic components in the bay bring a heat source, introducing a second scale in the problem. First, we present three levels of modelling for the physical phenomena, which are applied to the two sub-problems: the plane and the electronic component. Then, having reduced the complexity of the problem to a linear non-symmetric coercive PDE, we will use the reduced basis method for the electronic component problem. Nous considérons un problème multi-échelle d’aérothermie en aviation civile. Nous souhai- tons déterminer le champ de température dans un avion en conditions de vol, avec présence d’une climatisation. Des composants électroniques ventilés sont présents dans la soute, et constituent une source de chaleur, introduisant une deuxième échelle dans notre problème. Dans un premier temps, nous présentons trois niveaux de modélisation pour le phénomène d’aérothermie, que nous appliquerons aux deux sous-problèmes : l’avion et le composant électronique. Ensuite, nous appliquons la méthode des bases réduites au problème du composant électronique, en considérant des simplifications de modélisation amenant à la résolution numérique d’une EDP elliptique linéaire coercive non-symétrique.
Ford, Jackie
2015-04-01
There remains a conviction that the torrent of publications and the financial outlay on leadership development will create managers with the skills and characters of perfect leaders, capable of guiding healthcare organisations through the challenges and crises of the 21st century. The focus of much attention continues to be the search for the (illusory) core set of heroic qualities, abilities or competencies that will enable the development of leaders to achieve levels of supreme leadership and organisational performance. This brief commentary adds support to McDonald's (1) call for recognition of the complexity of the undertaking.
Directory of Open Access Journals (Sweden)
Jackie Ford
2015-04-01
Full Text Available There remains a conviction that the torrent of publications and the financial outlay on leadership development will create managers with the skills and characters of perfect leaders, capable of guiding healthcare organisations through the challenges and crises of the 21st century. The focus of much attention continues to be the search for the (illusory core set of heroic qualities, abilities or competencies that will enable the development of leaders to achieve levels of supreme leadership and organisational performance. This brief commentary adds support to McDonald’s (1 call for recognition of the complexity of the undertaking.
Amoebas of Complex Hypersurfaces in Statistical Thermodynamics
Energy Technology Data Exchange (ETDEWEB)
Passare, Mikael [Stockholm University, Department of Mathematics (Sweden); Pochekutov, Dmitry, E-mail: potchekutov@gmail.com [Siberian Federal University, Institute of Core Undergraduate Programmes (Russian Federation); Tsikh, August, E-mail: atsikh@sfu-kras.ru [Siberian Federal University, Institute of Mathematics (Russian Federation)
2013-03-15
The amoeba of a complex hypersurface is its image under the logarithmic projection. A number of properties of algebraic hypersurface amoebas are carried over to the case of transcendental hypersurfaces. We demonstrate the potential that amoebas can bring into statistical physics by considering the problem of energy distribution in a quantum thermodynamic ensemble. The spectrum {l_brace}{epsilon}{sub k}{r_brace} Subset-Of Z{sup n} of the ensemble is assumed to be multidimensional; this leads us to the notions of multidimensional temperature and a vector of differential thermodynamic forms. Strictly speaking, in the paper we develop the multidimensional Darwin-Fowler method and give the description of the domain of admissible average values of energy for which the thermodynamic limit exists.
Amoebas of complex hypersurfaces in statistical thermodynamics
Passare, Mikael; Tsikh, August
2011-01-01
The amoeba of a complex hypersurface is its image under a logarithmic projection. A number of properties of algebraic hypersurface amoebas are carried over to the case of transcendental hypersurfaces. We demonstrate the potential that amoebas can bring into statistical physics by considering the problem of energy distribution in a quantum thermodynamic ensemble. The spectrum ${\\epsilon_k}\\subset \\mathbb{Z}^n$ of the ensemble is assumed to be multidimensional; this leads us to the notions of a multidimensional temperature and a vector of differential thermodynamic forms. Strictly speaking, in the paper we develop the multidimensional Darwin and Fowler method and give the description of the domain of admissible average values of energy for which the thermodynamic limit exists.
Amoebas of Complex Hypersurfaces in Statistical Thermodynamics
Passare, Mikael; Pochekutov, Dmitry; Tsikh, August
2013-03-01
The amoeba of a complex hypersurface is its image under the logarithmic projection. A number of properties of algebraic hypersurface amoebas are carried over to the case of transcendental hypersurfaces. We demonstrate the potential that amoebas can bring into statistical physics by considering the problem of energy distribution in a quantum thermodynamic ensemble. The spectrum \\{\\varepsilon_k\\}subset {Z}^n of the ensemble is assumed to be multidimensional; this leads us to the notions of multidimensional temperature and a vector of differential thermodynamic forms. Strictly speaking, in the paper we develop the multidimensional Darwin-Fowler method and give the description of the domain of admissible average values of energy for which the thermodynamic limit exists.
Application of Complex Method in the Fracture Problem of Bimaterial%复变方法在双材料界面裂纹断裂分析中的应用研究
Institute of Scientific and Technical Information of China (English)
李俊林; 冯贵林; 陈蓓蓓; 张珺
2011-01-01
The problem of analytic function and generalized bi-harmonic operator on z, plane are studied；the application of the complex method interracial fracture mechanics is explored. The problem of fracture is transformed into a kind boundary value problem of generalized bi-harmonic partial differential equations, the formulae for bending moment, torque ,and stress of bending problems near semi-infinite interface the crack tip are derived.%研究了 zj 平面上解析函数及广义重调和算子,探索了复变函数方法在复合材料界面断裂力学上的应用,将正交异性双材料弯曲断裂问题化为一类广义重调和方程组边值问题,推出了弯曲问题半无限界面裂纹尖端附近的弯矩、扭矩、应力的计算公式.
Laughlin, Patrick R
2011-01-01
Experimental research by social and cognitive psychologists has established that cooperative groups solve a wide range of problems better than individuals. Cooperative problem solving groups of scientific researchers, auditors, financial analysts, air crash investigators, and forensic art experts are increasingly important in our complex and interdependent society. This comprehensive textbook--the first of its kind in decades--presents important theories and experimental research about group problem solving. The book focuses on tasks that have demonstrably correct solutions within mathematical
Yanagita, Takeshi; Kuroda, Shingo; Takano-Yamamoto, Teruko; Yamashiro, Takashi
2011-05-01
In this article, we report the successful use of miniscrews in a patient with an Angle Class III malocclusion, lateral open bite, midline deviation, and severe crowding. Simultaneously resolving such problems with conventional Class III treatment is difficult. In this case, the treatment procedure was even more challenging because the patient preferred to have lingual brackets on the maxillary teeth. As a result, miniscrews were used to facilitate significant asymmetric tooth movement in the posterior and downward directions; this contributed to the camouflage of the skeletal mandibular protrusion together with complete resolution of the severe crowding and lateral open bite. Analysis of the jaw motion showed that irregularities in chewing movement were also resolved, and a stable occlusion was achieved. Improvements in the facial profile and dental arches remained stable at the 18-month follow-up.
Henkin, G
2011-01-01
The purpose of this paper is to generalize in a geometric setting theorems of Severi, Brown and Bochner about analytic continuation of real analytic functions which are holomorphic or harmonic with respect to one of its variables. We prove in particular that if N is a real analytic levi-flat annulus in an open set of R^{n}\\timesC^{2}, then one can find X\\subsetR^{n}\\timesC^{2} such that X\\cupN is a levi-flat real analytic subset and X fills N in the sense that the boundary of the integration current of X is a prescribed smooth submanifold of N foliated by real curves. Moreover, real analytic functions on N whose restrictions to complex leaves are harmonic extend to X in functions of the same kind. We give also a theorem when the prescribed boundary is a cycle.
EarthObserver: Bringing the world to your fingertips
Ryan, W. B.; Goodwillie, A. M.; Coplan, J.; Carbotte, S. M.; Arko, R. A.; Ferrini, V.; O'hara, S. H.; Chan, S.; Bonczkowski, J.; Nitsche, F. O.; Morton, J. J.; McLain, K.; Weissel, R.
2011-12-01
EarthObserver (http://www.earth-observer.org/), developed by the Lamont-Doherty Earth Observatory of Columbia University, brings a wealth of geoscience data to Apple iPad, iPhone and iPod Touch mobile devices. Built around an easy-to-use interface, EarthObserver allows users to explore and visualise a wide range of data sets superimposed upon a detailed base map of land elevations and ocean depths - tapping the screen will instantly return the height or depth at that point. A simple transparency function allows direct comparison of built-in content. Data sets include high-resolution coastal bathymetry of bays, sounds, estuaries, harbors and rivers; geological maps of the US states and world - tapping the screen displays the rock type, and full legends can be viewed; US Topo sheets; and, geophysical content including seafloor crustal age and sediment thickness, earthquake and volcano data, gravity and magnetic anomalies, and plate boundary descriptions. The names of physiographic features are automatically displayed. NASA Visible Earth images along with ocean temperature, salinity and productivity maps and precipitation information expose data sets of interest to the atmospheric, oceanic and biological communities. Natural hazard maps, population information and political boundaries allow users to explore impacts upon society. EarthObserver, so far downloaded by more than 55,000 users, offers myriad ways for educators at all levels to bring research-quality geoscience data into the learning environment, whether for use as an in-class illustration or for extensive exploration of earth sciences data. By using cutting-edge mobile app technology, EarthObserver boosts access to relevant earth science content. The EarthObserver base map is the Global Multi-Resolution Topography digital elevation model (GMRT; http://www.marine-geo.org/portals/gmrt/), also developed at LDEO and updated regularly. It provides land elevations with horizontal resolution as high as 10m for
Problems over Information Systems
Chikalov, Igor
2011-01-01
The problems of estimation of the minimum average time complexity of decision trees and design of efficient algorithms are complex in general case. The upper bounds described in Chap. 2.4.3 can not be applied directly due to large computational complexity of the parameter M(z). Under reasonable assumptions about the relation of P and NP, there are no polynomial time algorithms with good approximation ratio [12, 32]. One of the possible solutions is to consider particular classes of problems and improve the existing results using characteristics of the considered classes. © Springer-Verlag Berlin Heidelberg 2011.
The British Child Support Agency: did American origins bring failure?
David P Dolowitz
2001-01-01
In late 1990 the British government published a two-volume White Paper, Children Come First: The Government's Proposals on the Maintenance of Children , announcing its intention to establish a Child Support Agency (CSA). In contrast with most of the literature associated with the British CSA, my main concern in this paper is not with the direct identification of the problems, or the perceived problems, the agency has experienced since its inception in 1993; it is with how the agency was devel...
Atoms for Peace Exhibition Science Bringing Nations Together
2000-01-01
CERN and JINR are providing safeguards on peaceful use of the potential of the Russian military and industrial complex by implementing scientific projects of the International Science and Technology Centre (ISTC).
... you are having balance problems, see your doctor. Balance disorders can be signs of other health problems, such ... cases, treating the illness that is causing the disorder will help with the balance problem. Exercises, a change in diet, and some ...
Directory of Open Access Journals (Sweden)
Muhammad Aslam Noor
2004-01-01
Full Text Available We consider a new class of equilibrium problems, known as hemiequilibrium problems. Using the auxiliary principle technique, we suggest and analyze a class of iterative algorithms for solving hemiequilibrium problems, the convergence of which requires either pseudomonotonicity or partially relaxed strong monotonicity. As a special case, we obtain a new method for hemivariational inequalities. Since hemiequilibrium problems include hemivariational inequalities and equilibrium problems as special cases, the results proved in this paper still hold for these problems.
Bringing the Science of JWST to the Public
Green, Joel D.; Smith, Denise A.; Lawton, Brandon L.; Meinke, Bonnie K.; Jirdeh, Hussein
2017-01-01
The James Webb Space Telescope is the successor to the Hubble Space Telescope. STScI and the Office of Public Outreach are committed to bringing awareness of the technology, the excitement, and the future science potential of this great observatory to the public and to the scientific community, prior to its 2018 launch. The challenges in ensuring the high profile of JWST (understanding the infrared, the vast distance to the telescope's final position, and the unfamiliar science territory) requires us to lay the proper background, particularly in the area of spectroscopy. We currently engage the full range of the public and scientific communities using a variety of high impact, memorable initiatives, in combination with modern technologies to extend reach, linking the science goals of Webb to the ongoing discoveries being made by Hubble. Webbtelescope.org, the public hub for scientific information related to JWST, is now open. We have injected Webb-specific content into ongoing outreach programs: for example, partnering with high impact science communicators such as MinutePhysics to produce timely and concise content; partnering with musicians and artists to link science and art. Augmented reality apps showcase NASA’s telescopes in a format usable by anyone with a smartphone, and visuals from increasingly affordable 3D VR technologies.
Bringing the Universe into the Community: Afterschool Astronomy and You
Krishnamurthi, Anita; Mitchell, S.; Reynolds, C. S.; Lochner, J.
2007-12-01
We present a successful afterschool program that astronomers can adopt and implement within their local communities with minimal effort. Our program targets middle school students in out-of-school-time settings and introduces basic astronomy concepts through hands-on activities, with a focus on the Universe beyond the solar system. It provides an opportunity for astronomers to work within their communities to introduce students to topics which hold significant interest but are not typically studied in school. The program is ideally run as a partnership between astronomers and local afterschool program providers - astronomers contribute the content expertise, and program leaders bring it to the audience. This program was successfully pilot tested with several hundred participants in 2006 and 2007 as the Beyond Einstein Explorers’ Program (BEEP). A comprehensive manual provides detailed recipes for running the program sessions, background information, materials lists, and extension activities and resources. Activity topics include the scale and structure of the Universe, the electromagnetic spectrum, spectroscopy, telescopes, stellar evolution, galaxies, black holes, and more. A flexible structure allows the program to be run in a variety of settings, including astronomy days, summer camps, or year-long afterschool programming. Astronomers who are interested in deeper involvement can partner with us to run training sessions and also add new modules to the program.
Using Augmented Reality to Bring interactivity to Metabolism Teaching
Directory of Open Access Journals (Sweden)
Galembeck E.
2014-08-01
Full Text Available INTRODUCTION: A glycolysis paper puzzle designed to introduce students to theprinciples of metabolic pathways have being used for several years, and it seems to helpstudents to learn the topic. We noticed that both the number of instructors and the timethey spend with the students, plays a major role in the success of the activity. Aninsufficient number of instructors do not permit adequate contact with all the students,which frustrate and discourage them. OBJECTIVES: In order to bring this activity to largeraudiences with a few instructors, we added a technological tool called augmented reality tothe paper puzzle. MATERIALS AND METHODS: The app was developed using Unity, and3D molecules obtained from Protein Data Bank. RESULTS AND DISCUSSION: Using thisapp the students were able to check their achievements as they progress through theactivity. The augmented reality also allowed the addition of more information to the cardslike answers to frequently asked questions and information via flashcards. The virtualflashcards displayed on the tablet screens show information such as the molecular 3Dstructure, and clues for assembling the puzzle. CONCLUSIONS: The above-mentionedtechnological improvement has enabled its use in larger classrooms with fewer instructorssince the students are able to have access to clues and discuss with the peers. Thus, thepaper puzzle is still the way students interact with each other, but the technological supportgives them more autonomy to solve the proposed exercises.
Bringing solar light to the bottom of the pyramid
Energy Technology Data Exchange (ETDEWEB)
Graham, S. [SGA Energy Ltd., Ottawa, ON (Canada)
2006-07-01
This presentation described the efforts in bringing solar light to areas of Rwanda, Uganda and the Congo that are currently unserved by electricity. In particular, it highlighted the contributions made by Light Up the World Foundation (LUTW) and the International Gorilla Conservation Programme (IGCP) to improve the quality of life in periphery villages by introducing solar LED lighting in 6 pilot villages. Efficient, long-lasting white LED lamps combined with solar can provide a low cost alternative to the current light source, which is kerosene, diesel and candles. It was noted that the technology exists, but the challenge lies in reaching the market and making a sustainable intervention. The operating parameters of solar panels, LED lamps and batteries were listed with reference to output power, open circuit voltage, maximum power voltage, maximum power current, and capacity. The service life of these devices was also listed along with estimates of their operating costs. The project needs were also identified. It was emphasized that financial support of IGCP and LUTW is needed to support private sector development and market expansion to other areas of Africa. figs.
Bringing Superconductor Digital Technology to the Market Place
Nisenoff, Martin
The unique properties of superconductivity can be exploited to provide the ultimate in electronic technology for systems such as ultra-precise analogue-to-digital and digital-to-analogue converters, precise DC and AC voltage standards, ultra high speed logic circuits and systems (both digital and hybrid analogue-digital systems), and very high throughput network routers and supercomputers which would have superior electrical performance at lower overall electrical power consumption compared to systems with comparable performance which are fabricated using conventional room temperature technologies. This potential for high performance electronics with reduced power consumption would have a positive impact on slowing the increase in the demand for electrical utility power by the information technology community on the overall electrical power grid. However, before this technology can be successfully brought to the commercial market place, there must be an aggressive investment of resources and funding to develop the required infrastructure needed to yield these high performance superconductor systems, which will be reliable and available at low cost. The author proposes that it will require a concerted effort by the superconductor and cryogenic communities to bring this technology to the commercial market place or make it available for widespread use in scientific instrumentation.
Disulfide Bridges: Bringing Together Frustrated Structure in a Bioactive Peptide.
Zhang, Yi; Schulten, Klaus; Gruebele, Martin; Bansal, Paramjit S; Wilson, David; Daly, Norelle L
2016-04-26
Disulfide bridges are commonly found covalent bonds that are usually believed to maintain structural stability of proteins. Here, we investigate the influence of disulfide bridges on protein dynamics through molecular dynamics simulations on the cysteine-rich trypsin inhibitor MCoTI-II with three disulfide bridges. Correlation analysis of the reduced cyclic peptide shows that two of the three disulfide distances (Cys(11)-Cys(23) and Cys(17)-Cys(29)) are anticorrelated within ∼1 μs of bridge formation or dissolution: when the peptide is in nativelike structures and one of the distances shortens to allow bond formation, the other tends to lengthen. Simulations over longer timescales, when the denatured state is less structured, do not show the anticorrelation. We propose that the native state contains structural elements that frustrate one another's folding, and that the two bridges are critical for snapping the frustrated native structure into place. In contrast, the Cys(4)-Cys(21) bridge is predicted to form together with either of the other two bridges. Indeed, experimental chromatography and nuclear magnetic resonance data show that an engineered peptide with the Cys(4)-Cys(21) bridge deleted can still fold into its near-native structure even in its noncyclic form, confirming the lesser role of the Cys(4)-Cys(21) bridge. The results highlight the importance of disulfide bridges in a small bioactive peptide to bring together frustrated structure in addition to maintaining protein structural stability.
Using Multimedia to Bring Science News to the Public
O'Riordan, C.; Stein, B.; Lorditch, E. M.
2015-12-01
Creative partnerships between scientists and journalists open new opportunities to bring the excitement of scientific discoveries to wider audiences. Research tells us that the majority of the general public now gets more science and technology news from the Internet than from TV sources (2014 NSF Science and Engineering Indicators). In order to reach these audiences news organizations must embrace multiple forms of multimedia. We will review recent research on how the new multimedia landscape is changing the way that science news is consumed and how news organizations are changing the way they deliver news. News programs like Inside Science, and other examples of new partnerships that deliver research news to journalists, teachers, students, and the general public will be examined. We will describe examples of successful collaborations including an article by a former Newsweek science reporter entitled "My 1975 'Cooling World' Story Doesn't Make Today's Climate Scientists Wrong," which got reprinted in Slate, RealClearScience, and mentioned in Factcheck.org and USA Today.
Macnaughton, Eric; Nelson, Geoffrey; Goering, Paula
2013-04-01
An interesting question concerns how large-scale (mental) health services policy initiatives come into being, and the role of evidence within the decision-making process behind their origins. This paper illustrates the process by which motivation to address homelessness, in the context of the upcoming 2010 Vancouver Olympics, was leveraged into a pan-Canadian project including sites in Vancouver, Winnipeg, Toronto, Montreal and Moncton, New Brunswick. The aim of the initiative was to implement and evaluate an intervention, Housing First, to provide housing and support to previously homeless people with mental illness. This qualitative case study was conducted between December 2009 and December 2010, employing grounded theory, and drawing on archival documents and interviews with 19 key informants involved in the conception of the project. Overall, the findings affirm that policy-making does not follow a rational, linear process of knowledge translation/exchange (KTE) and implementation, whereby evidence-based "products" are brought forward to address objectively determined needs and then "placed into decision-making events" (Lomas, 2007, p. 130). Instead, evidence-based policy making should be understood within the much more complex context of "policy entrepreneurship" (Kingdon, 2003; Mintrom & Norman, 2009) which entails taking advantage of windows of opportunity, and helping to bring together the "streams" of problems, politics, and policy ideas (Kingdon, 2003).
Supporting complex search tasks
DEFF Research Database (Denmark)
Gäde, Maria; Hall, Mark; Huurdeman, Hugo
2015-01-01
There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks, is fragme......There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks......, and recommendations, and supporting exploratory search to sensemaking and analytics, UI and UX design pose an overconstrained challenge. How do we know that our approach is any good? Supporting complex search task requires new collaborations across the whole field of IR, and the proposed workshop will bring together...
The Role of Religious and Scientific Leaders in Bringing Awareness to the Urgency of Climate Change.
Ramanathan, V.
2015-12-01
The release of the Encyclical by Pope Francis has opened a powerful new venue to bring forth the urgency of climate change to the public. The background work that preceded the encyclical was several years in the making. The Church has its own Science Academy, known as the Pontifical Academy of Sciences, consisting of 80 members from around the world with more than a third Nobel Laureates. The members are chosen for their scientific excellence (like most science academies of the world) and not for their religious affiliations. This academy organized a series of scientific meetings for the last 5 years, culminating in a 2014 workshop entitled: Sustainable Humanity, Sustainable Nature , Our Responsibility, jointly organized with the Pontifical Academy of Social Sciences. This meeting of the world's thought leaders in natural and Social sciences, came to a remarkable set of conclusions: Climate Change has become a moral issue. A fundamental change in our attitude towards natue and towards each other is required to solve the problem. Religious leaders can have a transformational effect by mobilizing public opinion for actions to stabilize climate change and protect the people. Being a council member of the Pontifical Academy and watching from within the powerful moral voice of Pope Francis, I conclude that this partnership with religion is a powerful new venue for those researchers, reticent about publicly voicing their grave concerns to pursue. We are going to bring massive public support for urgent actions only when the impacts of climate change and its origins are taught in every church, every temple, every mosque, every synagogue, and other places of worship.
Techniques for Analysing Problems in Engineering Projects
DEFF Research Database (Denmark)
Thorsteinsson, Uffe
1998-01-01
Description of how CPM network can be used for analysing complex problems in engineering projects.......Description of how CPM network can be used for analysing complex problems in engineering projects....
Bring into Full Play the Role of Catalytic Reforming Unit
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
This article after analyzing the current status of catalytic reforming technology in China puts forward a host of problems related with catalytic reforming capacity, feedstock, size and techno-economic indicators. To solve these problems it is proposed to properly increase the catalytic reforming capacity,extend the feedstock source, and eliminate the bottlenecks to boost the capacity of existing units, improve the operating and management level, as well as speed up R&D work, disseminate new technologies, new processes and novel catalysts.
Institute of Scientific and Technical Information of China (English)
张伟
2014-01-01
This article introduces the difficulties and technical problems encountered in the drilling operation in complex formation of scientific deep drilling projects.The main technical problems are broken formation drilling and strong shrinkage formation drilling.Technical measures for resolving the problems, referring to core drilling technologies, drill rig, drilling mud system and special drilling and cementing technologies used for strong shrinkage formation, are discussed.%介绍了在复杂地层科学深钻施工时遇到的困难和问题，主要包括破碎地层钻进问题和强缩径地层钻进问题，讨论了解决这些技术难题时采取的应对技术方案和措施，涉及取心钻进工艺方法和器具、钻机、泥浆体系以及极破碎、强缩径地层的特殊钻进、固井工艺和器具。
Tsednee, Tsogbayar; Yeager, Danny L
2015-01-01
We propose and develop the complex scaled multiconfigurational spin-tensor electron propagator (CMCSTEP) technique for theoretical determination of resonance parameters with electron-atom/molecule systems including open-shell and highly correlated atoms and molecules. The multiconfigurational spin-tensor electron propagator method (MCSTEP) developed and implemented by Yeager his coworkers in real space gives very accurate and reliable ionization potentials and attachment energies. The CMCSTEP method uses a complex scaled multiconfigurational self-consistent field (CMCSCF) state as an initial state along with a dilated Hamiltonian where all of the electronic coordinates are scaled by a complex factor. CMCSCF was developed and applied successfully to resonance problems earlier. We apply the CMCSTEP method to get $^2 P\\,\\mbox{Be}^{-}$ shape resonance parameters using $14s11p5d$, $14s14p2d$, and $14s14p5d$ basis sets with a $2s2p3d$\\,CAS. The obtained value of the resonance parameters are compared to previous res...
Equity and what secondary science teachers bring to the classroom
Austin, Barbara Anne
The demographics of people working in science-based careers do not match the demographics of the larger society. In particular, people who self-identify as Hispanic are underrepresented among working scientists. One reason may be the influence of formal schooling and more specifically, the behaviors of teachers in secondary science classrooms. This study looks at the practices of eight secondary science teachers at two schools at which 62% of the enrolled students declare their ethnicity as Hispanic. All of the teachers have at least three years of experience. Through interviews with the teachers, classroom observation, and interviews with other faculty, this research elucidates typical behaviors and attitudes surrounding teaching science in these settings. In spite of having a deficit view of their students, they all express interest in and concern about the students they teach. Their characterizations of teaching practices and classroom behaviors do not incorporate strategies designed to promote content learning through culturally relevant curriculum. Instead, they use mainstream-situated approaches that develop science content knowledge, vocabulary, procedures, and skills targeted toward high achievement on state and district standardized tests leading toward graduation or success in college. These approaches are consistent with a view of equity that increases the participation of underrepresented groups in science based careers in that it gives students the skills and knowledge they will need in order to successfully pursue these careers. Additionally, they behave in ways that are consistent with equitable strategies such as using inquiry based teaching, serving as role models, and providing a structured learning environment. This research informs the literature base for instructional systems designers by identifying what that teachers situated in culturally diverse classrooms bring to professional development programs targeted toward making secondary science
Gender equity and tobacco control: bringing masculinity into focus.
Morrow, Martha; Barraclough, Simon
2010-03-01
Gender is a key but often overlooked--determinant of tobacco use, especially in Asia, where sex-linked differences in prevalence rates are very large. In this article we draw upon existing data to consider the implications of these patterns for gender equity and propose approaches to redress inequity through gender-sensitive tobacco control activities. International evidence demonstrates that, in many societies, risk behaviours (including tobacco use) are practised substantially more by men and boys, and are also viewed as expressions of masculine identity. While gender equity focuses almost exclusively on the relative disadvantage of girls and women that exists in most societies, disproportionate male use of tobacco has profound negative consequences for men (as users) and for women (nonusers). Surprisingly, health promotion and tobacco control literature rarely focus on the role of gender in health risks among boys and men. However, tobacco industry marketing has masterfully incorporated gender norms, and also other important cultural values, to ensure its symbols are context-specific. By addressing gender-specific risks within the local cultural context--as countries are enjoined to do within the Framework Convention's Guiding Principles--it may be possible to accelerate the impact of mechanisms such as tobacco pricing, restrictions on marketing, smoking bans and provision of accurate information. It is essential that we construct a new research-to-policy framework for gender-sensitive tobacco control. Successful control of tobacco can only be strengthened by bringing males, and the concept of gender as social construction, back into our research and discussion on health and gender equity.
Imaginative ethics--bringing ethical praxis into sharper relief.
Hansson, Mats G
2002-01-01
The empirical basis for this article is three years of experience with ethical rounds at Uppsala University Hospital. Three standard approaches of ethical reasoning are examined as potential explanations of what actually occurs during the ethical rounds. For reasons given, these are not found to be satisfying explanations. An approach called "imaginative ethics", is suggested as a more satisfactory account of this kind of ethical reasoning. The participants in the ethical rounds seem to draw on a kind of moral competence based on personal life experience and professional competence and experience. By listening to other perspectives and other experiences related to one particular patient story, the participants imagine alternative horizons of moral experience and explore a multitude of values related to clinical practice that might be at stake. In his systematic treatment of aesthetics in the Critique of Judgement, Kant made use of an operation of thought that, if applied to ethics, will enable us to be more sensitive to the particulars of each moral situation. Based on this reading of Kant, an account of imaginative ethics is developed in order to bring the ethical praxis of doctors and nurses into sharper relief. The Hebraic and the Hellenic traditions of imagination are used in order to illuminate some of the experiences of ethical rounds. In conclusion, it is argued that imaginative ethics and principle-based ethics should be seen as complementary in order to endow a moral discourse with ethical authority. Kantian ethics will do the job if it is remembered that Kant suggested only a modest, negative role of principle-based deliberation.
Atmospheric effects of aviation. Bringing together science, technology and policy
Energy Technology Data Exchange (ETDEWEB)
Wesoky, H.L.; Friedl, R.R. [National Aeronautics and Space Administration, Washington, DC (United States)
1997-12-31
Sustained growth of the aviation industry could be threatened by environmental concerns. But collaboration of scientists, technologists and policy makers is helping to assess potential problems, and to consider appropriate measures for control of aircraft emissions. The structure of that collaboration is discussed along with status of the scientific assessments. (author) 15 refs.
"Diving in Deeper": Bringing Basic Writers' Thinking to the Surface
Smith, Cheryl Hogue
2010-01-01
This essay examines the problem of defining critical thinking and demonstrates how critical thinking is less a determinable process or set of procedures than a constellation of attitudes, habits of mind, role relations, and participation motives. It demonstrates further why college instruction in critical thinking in composition…
Boron brings big benefits to bio-based blends
The solution to the problems with bio-based lubrication can be approached by a combination of blending and additive strategies. However, many additives do not show efficacy when used in bio-based lubricants. Additive addition also lowers the bio-based content of the blend, which in turn limits the a...
Bringing the "Folk" into Applied Linguistics: An Introduction
Wilton, Antje; Stegu, Martin
2011-01-01
As applied linguistics is mainly concerned with solving the language-related problems of laypeople, the examination of folk views constitutes an important research field and its relevance is illustrated in this issue of the AILA review. In this introductory article, we address some of the more general aspects that need to be considered in the…
Bringing the Digital Camera to the Physics Lab
Rossi, M.; Gratton, L. M.; Oss, S.
2013-01-01
We discuss how compressed images created by modern digital cameras can lead to even severe problems in the quantitative analysis of experiments based on such images. Difficulties result from the nonlinear treatment of lighting intensity values stored in compressed files. To overcome such troubles, one has to adopt noncompressed, native formats, as…
WHAT DO TEACHERS BRING TO THE TEACHING-LEARNING PROCESS?
Institute of Scientific and Technical Information of China (English)
2000-01-01
This article, from the point of view of psychology, considers ways in which teachers seek to make sense of the learning process and suggests that their beliefs about learning and learners will have a profound influence on their teaching no matter what syllabus or course book they use. However, an understanding of what makes an effective teacher is inevitably more complex than this.
Storied Understandings: Bringing Aboriginal Voices to Canada's Multicultural Discourse
Syed, Khalida Tanvir
2010-01-01
This article discusses the implications and complexities of Canada's multicultural policies for aboriginal students in its post-secondary education systems. The author, a Pakistani-Canadian multicultural educator, interviewed an Aboriginal-Canadian multicultural educator, to discuss the cultural differences, divisions, and resistances between…
Beyond the Central Dogma: Bringing Epigenetics into the Classroom
Drits-Esser, Dina; Malone, Molly; Barber, Nicola C.; Stark, Louisa A.
2014-01-01
Epigenetics is the study of how external factors and internal cellular signals can lead to changes in the packaging and processing of DNA sequences, thereby altering the expression of genes and traits. Exploring the epigenome introduces students to environmental influences on our genes and the complexities of gene expression. A supplemental…
Reconciling Through Science Exhibition Science Bringing Nations Together
2000-01-01
The unique beams of the LHE accelerator complex attract physicists from France, Germany, Japan, Italy, USA and other countries. Scientists from over 120 institutes carry out experiments here. In 1993/1994 a new superconducting accelerator for relativistic nuclei, the Nuclotron, went into operation at Dubna.
Atoms for Peace Exhibition Science Bringing Nations Together
2000-01-01
"Atoms for Peace", this old slogan is gaining a new meaning today. Rejecting confrontation, mankind looks for new ways to unite the world. Political and economic integration makes it possible to use the great potential and high technologies of the military-industrial complex for constructing new scientific facilities.
Stopping to Squell the "Rhosus": Bringing Science Vocabulary to Life
Shore, Rebecca
2015-01-01
A research study conducted in an urban district middle school setting applies cognitive science principles to science vocabulary. Within the context of a personal story told by the lead investigator, the results of the study are shared and suggest that more active, engaging strategies with complex core curriculum may improve retention and…
Parkinson's disease and mitochondrial complex I: a perspective on the Ndi1 therapy.
Marella, Mathieu; Seo, Byoung Boo; Yagi, Takao; Matsuno-Yagi, Akemi
2009-12-01
Mitochondrial impairment has been collecting more and more attention as a contributing factor to the etiology of Parkinson's disease. Above all, the NADH-quinone oxidoreductase, complex I, of the respiratory chain seems to be most culpable. Complex I dysfunction is translated to an increased production of reactive oxygen species and a decreased energy supply. In the brain, the dopaminergic neurons are one of the most susceptible cells. Their death is directly linked to the disease apparition. Developing an effective gene therapy is challenged by harmful actions of reactive oxygen species. To overcome this problem a therapeutic candidate must be able to restore the NADH-quinone oxidoreductase activity regardless of how complex I is impaired. Here we discuss the potency of the yeast alternative NADH dehydrogenase, the Ndi1 protein, to reinstate the mitochondrial respiratory chain compensating for disabled complex I and the benefit Ndi1 brings toward retardation of Parkinson's disease.
A bilinear programming solution to the quadratic assignment problem
J.F. Kaashoek (Johan); J.H.P. Paelinck (Jean)
1999-01-01
textabstractThe quadratic assignment problem (QAP) or maximum acyclical graph problem is well documented (see e.g. Pardalos and Wolkowicz, 1994). One of the authors has published some material, in which it was tried, by structuring the problem additionally, to bring it as closely as possible in the
'The one truly serious philosophical problem': Ethical aspects of suicide.
Khan, Murad M; Mian, Ayesha I
2010-01-01
Suicide is a major global public health problem with an estimated one million deaths every year. It is one of the most personal yet one of the most complex acts anyone can perform, as it goes to the very core of the concept of human existence and the meaning of life. The philosophical debate on suicide has spanned centuries with no clear answers. Juxtaposed within the various perspectives that suicide can be studied from is the ethical perspective that brings into sharp focus the conflict between personal autonomy and societal responsibility towards suicidal individuals. Mental health professionals find themselves in the midst of this conflict as they are assumed to have the responsibility to prevent suicide in their patients, while patients' responsibility towards themselves is frequently overlooked. Mental health professionals need to be aware of the ethical concerns that arise in the care of suicidal patients.
Neron, Alex
Avec l'arrivée de l'environnement comme enjeu mondial, le secteur de l'efficacité énergétique prend une place de plus en plus importante pour les entreprises autant au niveau économique que pour l'image de la compagnie. Par le fait même, le domaine des technologies de l'énergie est un créneau de recherche dont les projets en cours se multiplient. D'ailleurs, un des problèmes qui peut survenir fréquemment dans certaines entreprises est d'aller mesurer la composition des matériaux dans des conditions difficiles d'accès. C'est le cas par exemple de l'électrolyse de l'aluminium qui se réalise à des températures très élevées. Pour pallier à ce problème, il faut créer et valider des modèles mathématiques qui vont calculer la composition et les propriétés à l'équilibre du système chimique. Ainsi, l'objectif global du projet de recherche est de développer un outil de calcul d'équilibres chimiques complexes (plusieurs réactions et plusieurs phases) et l'adapter aux problèmes électrochimiques et d'équilibres contraints. Plus spécifiquement, la plateforme de calcul doit tenir compte de la variation de température due à un gain ou une perte en énergie du système. Elle doit aussi considérer la limitation de l'équilibre due à un taux de réaction et enfin, résoudre les problèmes d'équilibres électrochimiques. Pour y parvenir, les propriétés thermodynamiques telles que l'énergie libre de Gibbs, la fugacité et l'activité sont tout d'abord étudiées pour mieux comprendre les interactions moléculaires qui régissent les équilibres chimiques. Ensuite, un bilan énergétique est inséré à la plateforme de calcul, ce qui permet de calculer la température à laquelle le système est le plus stable en fonction d'une température initiale et d'une quantité d'énergie échangée. Puis, une contrainte cinétique est ajoutée au système afin de calculer les équilibres pseudo-stationnaires en évolution dans le temps. De plus, la
Bringing Internet-based education and intervention into mental health practice: afterdeployment.org
Directory of Open Access Journals (Sweden)
Josef I. Ruzek
2011-11-01
Full Text Available Internet-facilitated interventions may offer numerous advantages in reaching the large numbers of military service men and women exposed to traumatic events. The Internet is now a primary source of health-related information for consumers and research has shown the effectiveness of web-based interventions in addressing a range of mental health problems.Clinicians can learn how to bring Internet education and intervention into routine care, to help clients better understand mental health issues and learn skills for self-management of problems.The Afterdeployment.org (AD Internet site can be used by health care professionals serving U.S. military personnel returning from Iraq and Afghanistan, and their families. The site currently addresses 18 key domains of functioning, including post-traumatic stress, sleep, anger, alcohol and drugs, and military sexual trauma. It provides an extensive amount of client and family education that is suitable for immediate use by clients and providers, as well as the kinds of interactive workshop content and self-assessment tools that have been shown to be helpful in other treatment contexts. AD can be utilized in clinical practice in a variety of ways: as an adjunct to treatment for PTSD, to supplement existing treatments for a range of post-deployment problems, or as the primary focus of treatment for a client.AD represents a kind of service that is likely to become increasingly available in coming years and that is important for mental health providers to actively explore as a tool for extending their reach, improving their efficiency, and improving quality of care.For the abstract or full text in other languages, please see Supplementary files under Reading Tools online.
Kaiserschnitten Wien - Let's bring the forest in the city
Directory of Open Access Journals (Sweden)
Ajda Primožič
2012-01-01
Full Text Available The location is part of the Vienna River Valley, known as "Wiental", one of the most dissonant, incongruous, and contested areas of Vienna. Depending on one’s perspective, the Vienna River Valley can be viewed as a transit corridor, an unresolved urban area, an urban interface, an inter- zone, an infrastructure bundle, an ugly wound in the urban landscape, a socially charged boundary, etc. We started the project with urban pattern analyses on different scales: the scale of the city, the scale of Wiental (from Schönbrunn to Hofburg and on a minor scale, i.e. the scale of the project.The analysis showed that Wiental constitutes the main connection between the city centre and suburbia and the countryside in the background of the city. With its clear morphological importance, it could become a green axis of the city, a pleasant place for people, rather than having only an infrastructural role. Our concept is to bring new character to Wiental by making it a pedestrian- and cyclist-friendly green axis. Our initial goal was to reduce car traffic. We proposed introducing a park-and-ride system, which would become a point of transfer where car traffic is replaced by public transport and cycle traffic. Through the afforestation of Wiental, the area could become a park or recreational route, and the quality of life in the area would improve.An important aspect of the project was dealing with the Danube. We proposed to manage the flood peaks by introducing a dam, and after the point of regulation, we arranged the River into two levels: an ambient upper flow and infrastructural lower flow in the existing channel. Also, by rearranging "Naschmarkt" with the Danube uncovered, we predicted an extension of tourism from the city centre to Schönbrunn by bicycle or on foot, which could be followed by an expansion of the public programme. We wanted to show that the Danube, with an appropriate environment, could become a significant element of the city structure.
Euarchontan Opsin Variation Brings New Focus to Primate Origins
Melin, Amanda D.; Wells, Konstans; Moritz, Gillian L.; Kistler, Logan; Orkin, Joseph D.; Timm, Robert M.; Bernard, Henry; Lakim, Maklarin B.; Perry, George H.; Kawamura, Shoji; Dominy, Nathaniel J.
2016-01-01
Debate on the adaptive origins of primates has long focused on the functional ecology of the primate visual system. For example, it is hypothesized that variable expression of short- (SWS1) and middle-to-long-wavelength sensitive (M/LWS) opsins, which confer color vision, can be used to infer ancestral activity patterns and therefore selective ecological pressures. A problem with this approach is that opsin gene variation is incompletely known in the grandorder Euarchonta, that is, the orders...
Problem solving using soft systems methodology.
Land, L
This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.
Institute of Scientific and Technical Information of China (English)
熊劲松; 高兴宝
2015-01-01
This paper proposes preconditioned modified AHSS method for a class of complex singular saddle point problems. It studies the semi-convergence of the proposed new method. For any positive iteration parameters, it obtains the semi-convergence theorems of the proposed new method. Nnumerical experiments show that the effectiveness of the algorithm outperforms the HSS method.%提出了求解一类复奇异鞍点问题的预条件修正AHSS法。研究了所提出的新方法的半收敛性。对任意的正迭代参数，得到了所提出的新方法的半收敛定理。数值实验说明，新方法比HSS法求解鞍点问题时更有效。
... your legs or feet Movement disorders such as Parkinson's disease Diseases such as arthritis or multiple sclerosis Vision or balance problems Treatment of walking problems depends on the cause. Physical therapy, surgery, or mobility aids may help.
... know the exact cause of your prostate problem. Prostatitis The cause of prostatitis depends on whether you ... prostate problem in men older than age 50. Prostatitis If you have a UTI, you may be ...
Once Upon a Time ... Exhibition Science Bringing Nations Together
2000-01-01
In 1956, a year and a half after the establishment of the European Organization for Nuclear Research, CERN, the states of the "socialist bloc" signed an agreement establishing a similar international centre for the study of fundamental problems in physics: the Joint Institute for Nuclear Research, JINR. The seat of the Institute was chosen to be the town of Dubna, 120 km north of Moscow. Though the establish-ment of JINR was clearly a political response, during the Cold War, to the establishment of CERN, from the very beginning the Institute's activities were aimed solely at investigating the fundamental properties of matter and using scientific discoveries for peaceful purposes.
Bringing Home the Japanese Abductees from North Korea
Directory of Open Access Journals (Sweden)
ITO, Takuya
2007-11-01
Full Text Available This paper discusses the official and unofficial attitude of former Japanese prime minister Abe Shinzo towards the abductions of Japanese people by North Korea. Officially, Abe displayed an aggressive attitude towards the problem. However, unofficially, he possessed an ingratiating attitude. A Japanese weekly magazine reported that he had been in regular negotiations with North Korea surreptitiously. Abe's ingratiating attitude may be explained by his alleged connection with the Holy Spirit Association for the Unification of World Christianity—which preaches the establishment of a harmonious relationship with North Korea. Abe's dual attitude confounded the families of the abductees as they were unable to ascertain which of his attitudes was genuine.
Wild, Walter J.
1980-01-01
Discusses the simplest three-body problem, known as Euler's problem. The article, intended for students in the undergraduate mathematics and physics curricula, shows how the complex equations for a specific three-body problem can be solved on a small calculator. (HM)
Synthetic real estate: bringing corporate finance to health care.
Varwig, D; Smith, J
1998-01-01
The changing landscape of health care has caused hospitals, health care systems, and other health care organizations to look for ways to finance expansions and acquisitions without "tainting" their balance sheets. This search has led health care executives to a financing technique that has been already embraced by Fortune 500 companies for most of this decade and more recently adopted by high-tech companies: synthetic real estate. Select case studies provide examples of the more creative financial structures currently being employed to meet rapidly growing and increasingly complex funding needs.
Oncology Advanced Practitioners Bring Advanced Community Oncology Care.
Vogel, Wendy H
2016-01-01
Oncology care is becoming increasingly complex. The interprofessional team concept of care is necessary to meet projected oncology professional shortages, as well as to provide superior oncology care. The oncology advanced practitioner (AP) is a licensed health care professional who has completed advanced training in nursing or pharmacy or has completed training as a physician assistant. Oncology APs increase practice productivity and efficiency. Proven to be cost effective, APs may perform varied roles in an oncology practice. Integrating an AP into an oncology practice requires forethought given to the type of collaborative model desired, role expectations, scheduling, training, and mentoring.
Complex shape product tolerance and accuracy control method for virtual assembly
Ma, Huiping; Jin, Yuanqiang; Zhang, Xiaoguang; Zhou, Hai
2015-02-01
The simulation of virtual assembly process for engineering design lacks of accuracy in the software of three-dimension CAD at present. Product modeling technology with tolerance, assembly precision preanalysis technique and precision control method are developed. To solve the problem of lack of precision information transmission in CAD, tolerance mathematical model of Small Displacement Torsor (SDT) is presented, which can bring about technology transfer and establishment of digital control function for geometric elements from the definition, description, specification to the actual inspection and evaluation process. Current tolerance optimization design methods for complex shape product are proposed for optimization of machining technology, effective cost control and assembly quality of the products.
From the Moon: Bringing Space Science to Diverse Audiences
Runyon, C. J.; Hall, C.; Joyner, E.; Meyer, H. M.; M3 Science; E/PO Team
2011-12-01
NASA's Apollo missions held a place in the mindset of many Americans - we dared to go someplace where humans had never set foot, a place unknown and beyond our imaginations. These early NASA missions and discoveries resulted in an enhanced public understanding of the Moon. Now, with the human element so far removed from space exploration, students must rely on textbooks, TV's, and computers to build their understanding of our Moon. However, NASA educational materials about the Moon are stale and out-of-date. In addition, they do not effectively address 21st Century Skills, an essential for today's classrooms. Here, we present a three-part model for developing opportunities in lunar science education professional development that is replicable and sustainable and integrates NASA mission-derived data (e.g., Moon Mineralogy Mapper (M3)/Chandrayaan-1). I) With the return of high resolution/high spatial data from M3/Chandrayaan-1, we can now better explore and understand the compositional variations on the lunar surface. Data and analysis techniques from the imaging spectrometer are incorporated into the M3 Educator's Guide: Seeing the Moon in a New Light. The guide includes an array of activities and lessons to help educators and students understand how NASA is currently exploring the Moon. The guide integrates NASA maps and data into the interactive lessons, bringing the excitement of scientific exploration and discovery into the classroom. II) Utilizing the M3 Educator's Guide as well as educational activities from more current NASA lunar missions, we offer two sustained professional development opportunities for educators to explore the Moon through interactive and creative strategies. 1) Geology of the Moon, an online course offered through Montana State University's National Teacher Enhancement Network, is a 3-credit graduate course. 2) Fly Me to the Moon, offered through the College of Charleston's Office of Professional Development in Education, is a two
Projectively related complex Finsler metrics
Aldea, Nicoleta
2011-01-01
In this paper we introduce in study the projectively related complex Finsler metrics. We prove the complex versions of the Rapcs\\'{a}k's theorem and characterize the weakly K\\"{a}hler and generalized Berwald projectively related complex Finsler metrics. The complex version of Hilbert's Fourth Problem is also pointed out. As an application, the projectiveness of a complex Randers metric is described.
Bringing politics back into water planning scenarios in Europe
Fernandez, Sara; Bouleau, Gabrielle; Treyer, Sébastien
2014-10-01
The shift from government to governance in European water policies conveys a pluralist conception of stakeholder participation in planning. This article argues that the current Driving forces-Pressures-State-Impact-Response (DPSIR) approach to the planning of natural resource use, developed by the Organisation for Economic Cooperation and Development (OECD) and the European Environmental Agency (EEA) is at odds with a pluralistic conception. The DPSIR approach consists in constructing a single socio-environmental model to address a specific problem in water management, while paying no attention to the existence of conflicts surrounding the definition of the issue at hand, the social, political and spatial delimitation of that issue, and the translation of stakes in terms of quantitative variables. Scenarios produced in this process therefore explore a limited range of policies, i.e. those defining the problem in the same way, as illustrated here with the case of the Garonne River in France. This article presents an alternative method, combining knowledge in social science and natural determinisms to build contrasting socio-hydrological scenarios that do not share the same hypotheses regarding their respective key issues.
Can mouse imaging studies bring order to autism connectivity chaos?
Directory of Open Access Journals (Sweden)
Adam Liska
2016-11-01
Full Text Available Functional Magnetic Resonance Imaging (fMRI has consistently highlighted impaired or aberrant functional connectivity across brain regions of autism spectrum disorder (ASD patients. However, the manifestation and neural substrates of these alterations are highly heterogeneous and often conflicting. Moreover, their neurobiological underpinnings and etiopathological significance remain largely unknown. A deeper understanding of the complex pathophysiological cascade leading to aberrant connectivity in ASD can greatly benefit from the use of model organisms where individual pathophysiological or phenotypic components of ASD can be recreated and investigated via approaches that are either off limits or confounded by clinical heterogeneity. Despite some obvious limitations in reliably modelling the full phenotypic spectrum of a complex developmental disorder like ASD, mouse models have played a central role in advancing our basic mechanistic and molecular understanding of this syndrome. Recent progress in mouse brain connectivity mapping via resting-state fMRI (rsfMRI offers the opportunity to generate and test mechanistic hypotheses about the elusive origin and significance of connectional aberrations observed in autism. Here we discuss recent progress towards this goal, and illustrate initial examples of how the approach can be employed to establish causal links between ASD-related mutations, developmental processes, and brain connectional architecture. As the spectrum of genetic and pathophysiological components of ASD modelled in the mouse is rapidly expanding, the use of rsfMRI can advance our mechanistic understanding of the origin and significance of the connectional alterations associated with autism, and their heterogeneous expression across patient cohorts.
Using Plants to Explore the Nature & Structural Complexity of Life
Howard, Ava R.
2014-01-01
Use of real specimens brings the study of biology to life. This activity brings easily acquired plant specimens into the classroom to tackle common alternative conceptions regarding life, size, complexity, the nature of science, and plants as multicellular organisms. The activity occurs after a discussion of the characteristics of life and engages…
Mathematical Control of Complex Systems 2013
Zidong Wang; Hamid Reza Karimi; Bo Shen; Jun Hu; Hongli Dong; Xiao He
2014-01-01
Mathematical control of complex systems have already become an ideal research area for control engineers, mathematicians, computer scientists, and biologists to understand, manage, analyze, and interpret functional information/dynamical behaviours from real-world complex dynamical systems, such as communication systems, process control, environmental systems, intelligent manufacturing systems, transportation systems, and structural systems. This special issue aims to bring together the latest...
Complex Systems: Control and Modeling Problems
2004-08-23
Artificial Intelligence . [2] Kalpic B., Bernus P. Busin tool in enterprise management. Elsevier. [3] Vernadat, F. de la Conférence MOS r Solving...A huge intellectual effort has been spent during the last fifty years researching this area, under the name of Artificial Intelligence , albeit with...Agent-Based Support of Mass Customization for Cor- porate Knowledge Management. Eng. Applications of Artificial Intelligence , Vol. 16, No. 4
Institute of Scientific and Technical Information of China (English)
张庆杰; 王俊生; 金忠庆; 沈锡强
2013-01-01
针对复杂网络条件下多UAV系统任务区集结问题,提出了多机非合作求解方法.首先,基于协调变量和协调函数,建立多UAV集结问题的分布式求解框架.从任务特征出发,改进多智能体时延相关平均一致性算法,提出非合作优化一致性策略.该方法更强调平台的轨迹控制,弱化UAV对路径规划算法的要求,不仅能够降低集结问题的求解难度,而且使多UAV系统具有较强的动态响应能力.仿真实验验证了非合作优化一致性策略的正确性,多UAV能够在复杂网络条件下实现任务集结.%To solve the rendezvous problem in mission area for multiple unmanned aerial vehicles (UAVs) system in complex network,a non-cooperative method is proposed.Firstly,the distributed solving framework is provided based on coordination variables and coordination function.Considering the characteristics of the task,delay-dependent average consensus algorithm of multi-agent system is improved,and the non-cooperative optimal consensus strategy is presented.The proposed method emphasizes on the trajectory control of the platform,and thus weakens the requirements of the UAVs for the path planning algorithm.It can not only reduce the difficulty of solving rendezvous problem,but also strengthen the dynamic response capabilities of the mnlti-UAV system.The simulation results show the effectiveness of the proposed method,and it is valid for solving the rendezvous problem of multi-UAV system in complex network.
DEFF Research Database (Denmark)
Tietjen, Anne; Jørgensen, Gertrud
2016-01-01
In a time of increasing globalisation and urbanisation, shrinking peripheral rural areas have become a truly wicked planning problem in many European countries. Although a problem can be easily perceived and measured by various indicators, the precise definition of the problem is problematic. Based......, place-based and project-oriented process directed at concrete physical outcomes. We frame strategic planning as a translation process where the interaction between human and non-human actors translates a unique, complex and contested situation into an innovated situation. We find that local physical...
36 CFR 1280.18 - May I bring guns or other weapons onto NARA property?
2010-07-01
... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false May I bring guns or other weapons onto NARA property? 1280.18 Section 1280.18 Parks, Forests, and Public Property NATIONAL ARCHIVES... Conduct on NARA Property? Prohibited Activities § 1280.18 May I bring guns or other weapons onto...
Bringing together components of the fly renal system.
Denholm, Barry; Skaer, Helen
2009-10-01
The function of all animal excretory systems is to rid the body of toxins and to maintain homeostatic balance. Although excretory organs in diverse animal species appear superficially different they are often built on two common principals: filtration and tubular secretion/reabsorbtion. The Drosophila excretory system is composed of filtration nephrocytes and Malpighian (renal) tubules. Here we review recent molecular genetic data on the development and differentiation of nephrocytes and renal tubules. We focus in particular on the molecular mechanisms that underpin key cell and tissue behaviours during morphogenesis, drawing parallels with other species where they exist. Finally we assess the implications of patterned tissue differentiation for the subsequent regulation of renal function. These studies highlight the continuing usefulness of the fly to provide fundamental insights into the complexities of organ formation.
Dynamics of mathematical models in biology bringing mathematics to life
Zazzu, Valeria; Guarracino, Mario
2016-01-01
This volume focuses on contributions from both the mathematics and life science community surrounding the concepts of time and dynamicity of nature, two significant elements which are often overlooked in modeling process to avoid exponential computations. The book is divided into three distinct parts: dynamics of genomes and genetic variation, dynamics of motifs, and dynamics of biological networks. Chapters included in dynamics of genomes and genetic variation analyze the molecular mechanisms and evolutionary processes that shape the structure and function of genomes and those that govern genome dynamics. The dynamics of motifs portion of the volume provides an overview of current methods for motif searching in DNA, RNA and proteins, a key process to discover emergent properties of cells, tissues, and organisms. The part devoted to the dynamics of biological networks covers networks aptly discusses networks in complex biological functions and activities that interpret processes in cells. Moreover, chapters i...
Bringing the CMS distributed computing system into scalable operations
Belforte, S; Fisk, I; Flix, J; HernÃ¡ndez, J M; Kress, T; Letts, J; Magini, N; Miccio, V; SciabÃ , A
2010-01-01
Establishing efficient and scalable operations of the CMS distributed computing system critically relies on the proper integration, commissioning and scale testing of the data and workload management tools, the various computing workflows and the underlying computing infrastructure, located at more than 50 computing centres worldwide and interconnected by the Worldwide LHC Computing Grid. Computing challenges periodically undertaken by CMS in the past years with increasing scale and complexity have revealed the need for a sustained effort on computing integration and commissioning activities. The Processing and Data Access (PADA) Task Force was established at the beginning of 2008 within the CMS Computing Program with the mandate of validating the infrastructure for organized processing and user analysis including the sites and the workload and data management tools, validating the distributed production system by performing functionality, reliability and scale tests, helping sites to commission, configure an...
The making of a portrait--bringing it into focus.
Zeng, X
2003-12-01
The data generated by DNA arrays are often described as the molecular "portrait" of a particular physiological/pathological sample. Although the emotional reactions could range from revulsion to adoration when viewing those portraits, as it might be when viewing some contemporary art, array technology has fundamentally changed the way researchers approach many biomedical questions. With its ability to monitor the expression level of tens of thousands genes simultaneously, microarray technology has been able to identify "markers" for complex diseases such as cancer. While massive amounts of work lie ahead to validate those marker genes, many researchers are turning their attentions to the low-density, focused arrays. When incorporated with current knowledge on specific biological pathways, these specially tailored macroarrays may be better fitted for purposes such as diagnosis, drug discovery and validation, and prognostic assessment of clinical treatments.
Energy Technology Data Exchange (ETDEWEB)
Chassin, David P.; Posse, Christian; Malard, Joel M.
2004-08-01
Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.
Institute of Scientific and Technical Information of China (English)
王华宁; 何平; 曹志远
2013-01-01
对边界几何形状、位置随时间变化的变边界结构,给出了用复变函数求解粘弹问题的解析方法.文中用拉普拉斯变换结合平面弹性复变方法,对内外边界变化时粘弹性轴对称问题进行求解.引入两个与时间、空间相关的解析函数,给出了变边界情况下应力、位移以及边界条件与解析函数的关系.当解析函数形式部分确定,则可用边界条件求解其中与时间相关的待定函数.求解待定函数的方程一般情况下为一系列积分方程,特殊情况可求得解析解.对轴对称问题中应力边值问题、位移边值问题以及混合边值问题,分别利用边界条件求得相关系数,从而得到了应力与位移的解析表达.当取Boltzmann粘弹模型时,进行不同边值问题的分析.分析显示,应力、位移的形态与大小均与边界变化过程相关,与固定边界粘弹性问题有较大不同.本文解答可用于粘弹性轴对称问题内外边界任意变化及各种边值问题的力学分析.此外,该法可进一步进行荷载非对称、复杂孔型变边界问题的求解.%This paper presents the complex variable method for viscoelastic problem whose boundaries are varied with time. Laplace transformation is introduced to complex variable method to solve the axisymmetric problem of viscoelasticity. Stress and displacement fields,and boundary conditions are expressed by two analytical functions in terms of time and space,and coefficients in analytical functions can be determined by the boundary conditions. The equations about the coefficients are generally in integral form, but analytical solutions can be obtained in special cases. For the axisymmetric problems of stress,displacement or mixed boundary,the corresponding coefficients are determined exactly by boundary conditions and analytical solutions of displacement and stresses are given also. As an application example, Boltzmann viscoelastic model is employed. The solutions
Flanigan, Francis J
2010-01-01
A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion
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Resilience by Design: Bringing Science to Policy Makers
Jones, Lucile M.
2015-01-01
No one questions that Los Angeles has an earthquake problem. The “Big Bend” of the San Andreas fault in southern California complicates the plate boundary between the North American and Pacific plates, creating a convergent component to the primarily transform boundary. The Southern California Earthquake Center Community Fault Model has over 150 fault segments, each capable of generating a damaging earthquake, in an area with more than 23 million residents (Fig. 1). A Federal Emergency Management Agency (FEMA) analysis of the expected losses from all future earthquakes in the National Seismic Hazard Maps (Petersen et al., 2014) predicts an annual average of more than $3 billion per year in the eight counties of southern California, with half of those losses in Los Angeles County alone (Federal Emergency Management Agency [FEMA], 2008). According to Swiss Re, one of the world’s largest reinsurance companies, Los Angeles faces one of the greatest risks of catastrophic losses from earthquakes of any city in the world, eclipsed only by Tokyo, Jakarta, and Manila (Swiss Re, 2013).
Will Mobile Learning Bring a Paradigm Shift in Higher Education?
Directory of Open Access Journals (Sweden)
Lalita Rajasingham
2011-01-01
Full Text Available In the light of technology-driven social change that creates new challenges for universities, this paper considers the potential of mobile learning as a subset of e-learning to effect a paradigm shift in higher education. Universities face exponential growth in demand for higher education, significant decreases in government funding for education, a changing in understanding of the nature of knowledge, changing student demographics and expectations, and global competition. At the same time untethered mobile telephony is connecting large numbers of potential learners to communications networks. A review of some empirical literature on the current status of mobile learning that explores alternatives to help universities fulfil core functions of storage, processing, and disseminating knowledge that can be applied to real life problems, is followed by an examination of the strengths and weaknesses of increased connectivity to mobile communications networks to support constructivist, self-directed quality interactive learning for increasingly mobile learners. This paper also examines whether mobile learning can align the developing technology with changing student expectations and the implications of such an alignment for teaching and institutional strategies. Technologies considered include mobile computing and technology, wireless laptop, hand-held PDAs, and mobile telephony.
Euarchontan Opsin Variation Brings New Focus to Primate Origins.
Melin, Amanda D; Wells, Konstans; Moritz, Gillian L; Kistler, Logan; Orkin, Joseph D; Timm, Robert M; Bernard, Henry; Lakim, Maklarin B; Perry, George H; Kawamura, Shoji; Dominy, Nathaniel J
2016-04-01
Debate on the adaptive origins of primates has long focused on the functional ecology of the primate visual system. For example, it is hypothesized that variable expression of short- (SWS1) and middle-to-long-wavelength sensitive (M/LWS) opsins, which confer color vision, can be used to infer ancestral activity patterns and therefore selective ecological pressures. A problem with this approach is that opsin gene variation is incompletely known in the grandorder Euarchonta, that is, the orders Scandentia (treeshrews), Dermoptera (colugos), and Primates. The ancestral state of primate color vision is therefore uncertain. Here, we report on the genes (OPN1SW and OPN1LW) that encode SWS1 and M/LWS opsins in seven species of treeshrew, including the sole nocturnal scandentian Ptilocercus lowii. In addition, we examined the opsin genes of the Central American woolly opossum (Caluromys derbianus), an enduring ecological analogue in the debate on primate origins. Our results indicate: 1) retention of ultraviolet (UV) visual sensitivity in C. derbianus and a shift from UV to blue spectral sensitivities at the base of Euarchonta; 2) ancient pseudogenization of OPN1SW in the ancestors of P. lowii, but a signature of purifying selection in those of C. derbianus; and, 3) the absence of OPN1LW polymorphism among diurnal treeshrews. These findings suggest functional variation in the color vision of nocturnal mammals and a distinctive visual ecology of early primates, perhaps one that demanded greater spatial resolution under light levels that could support cone-mediated color discrimination.
Bringing Experiment Software to the Web with VISPA
Erdmann, M.; Fischer, B.; Fischer, R.; Glaser, C.; Heidemann, F.; Müller, G.; Quast, T.; Rieger, M.; Urban, M.; van Asseldonk, D.; von Cube, R. F.; Welling, C.
2016-10-01
The Visual Physics Analysis (VISPA) software is a toolbox for accessing analysis software via the web. It is based on latest web technologies and provides a powerful extension mechanism that enables to interface a wide range of applications. It especially meets the demands of sophisticated experiment-specific use cases that focus on physics data analyses and typically require a high degree of interactivity. As an example, we developed a data inspector which is capable of browsing interactively through event content of several data formats, e.g., MiniAOD which is utilized by the CMS collaboration. Visual control of a chain of user analysis modules as well as visualization of user specific workflows support users in rather complex analyses at the level of ttH cross section measurements. The VISPA extension mechanism is also used to embed external web-based applications which benefit from dynamic allocation of user-defined computing resources via SSH. For example, by wrapping the JSROOT project, ROOT files located on any remote machine can be inspected directly through a VISPA server instance. We present the techniques of the extension mechanism and corresponding applications.
Directory of Open Access Journals (Sweden)
Xavier Montagud-Mayor
2015-12-01
Full Text Available Since some years its clear the increasing difficulty of the social services to join in situations that arise in the context of multiplicity and instability. This reality, traditionally conceived as an expression of the complexity of society can also be observed from a particular approach and little known social problems: the wicked problems, that brings us to another way of understanding them. His qualities lead us to reflect on the possibility of the coexistence of certain limits on the ability of organizations and professionals to achieve outcomes which significantly improve the situations they face. At the same time we see in those limits the opportunity to expand and improve our capabilities and skills through the use of a little known research strategy: autoethnography. With it we can scrutinize the memory of our expertise to identify the problems we deal and develop the talent that many social workers possess.
Where humans meet machines innovative solutions for knotty natural-language problems
Markowitz, Judith
2013-01-01
Where Humans Meet Machines: Innovative Solutions for Knotty Natural-Language Problems brings humans and machines closer together by showing how linguistic complexities that confound the speech systems of today can be handled effectively by sophisticated natural-language technology. Some of the most vexing natural-language problems that are addressed in this book entail recognizing and processing idiomatic expressions, understanding metaphors, matching an anaphor correctly with its antecedent, performing word-sense disambiguation, and handling out-of-vocabulary words and phrases. This fourteen-chapter anthology consists of contributions from industry scientists and from academicians working at major universities in North America and Europe. They include researchers who have played a central role in DARPA-funded programs and developers who craft real-world solutions for corporations. These contributing authors analyze the role of natural language technology in the global marketplace; they explore the need f...
Skovhus, Randi Boelskifte; Thomsen, Rie
2017-01-01
This article introduces a method to critical reviews and explores the ways in which problems have been formulated in knowledge production on career guidance in Denmark over a 10-year period from 2004 to 2014. The method draws upon the work of Bacchi focussing on the "What's the problem represented to be" (WPR) approach. Forty-nine…
Biological Computation as the Revolution of Complex Engineered Systems
Gómez-Cruz, Nelson Alfonso
2011-01-01
Provided that there is no theoretical frame for complex engineered systems (CES) as yet, this paper claims that bio-inspired engineering can help provide such a frame. Within CES bio-inspired systems play a key role. The disclosure from bio-inspired systems and biological computation has not been sufficiently worked out, however. Biological computation is to be taken as the processing of information by living systems that is carried out in polynomial time, i.e., efficiently; such processing however is grasped by current science and research as an intractable problem (for instance, the protein folding problem). A remark is needed here: P versus NP problems should be well defined and delimited but biological computation problems are not. The shift from conventional engineering to bio-inspired engineering needs bring the subject (or problem) of computability to a new level. Within the frame of computation, so far, the prevailing paradigm is still the Turing-Church thesis. In other words, conventional engineering...
How can scientists bring research to use: the HENVINET experience
Directory of Open Access Journals (Sweden)
Bartonova Alena
2012-06-01
Full Text Available Abstract Background Health concerns have driven the European environmental policies of the last 25 years, with issues becoming more complex. Addressing these concerns requires an approach that is both interdisciplinary and engages scientists with society. In response to this requirement, the FP6 coordination action “Health and Environment Network” HENVINET was set up to create a permanent inter-disciplinary network of professionals in the field of health and environment tasked to bridge the communication gap between science and society. In this paper we describe how HENVINET delivered on this task. Methods The HENVINET project approached the issue of inter-disciplinary collaboration in four ways. (1 The Drivers-Pressures-State-Exposure-Effect-Action framework was used to structure information gathering, collaboration and communication between scientists in the field of health and the environment. (2 Interactive web-based tools were developed to enhance methods for knowledge evaluation, and use these methods to formulate policy advice. (3 Quantification methods were adapted to measure scientific agreement. And (4 Open architecture web technology was used to develop an information repository and a web portal to facilitate collaboration and communication among scientists. Results Twenty-five organizations from Europe and five from outside Europe participated in the Health and Environment Network HENVINET, which lasted for 3.5 years. The consortium included partners in environmental research, public health and veterinary medicine; included medical practitioners and representatives of local administrations; and had access to national policy making and EEA and WHO expertise. Dedicated web-based tools for visualisation of environmental health issues and knowledge evaluation allowed remote expert elicitation, and were used as a basis for developing policy advice in five health areas (asthma and allergies; cancer; neurodevelopmental disorders
Bringing Terramechanics to bear on Planetary Rover Design
Richter, L.
2007-08-01
Thus far, planetary rovers have been successfully operated on the Earth's moon and on Mars. In particular, the two NASA Mars Exploration Rovers (MERs) ,Spirit' and ,Opportunity' are still in sustained daily operations at two sites on Mars more than 3 years after landing there. Currently, several new planetary rover missions are in development targeting Mars (the US Mars Science Lab vehicle for launch in 2009 and ESA's ExoMars rover for launch in 2013), with lunar rover missions under study by China and Japan for launches around 2012. Moreover, the US Constellation program is preparing pre-development of lunar rovers for initially unmanned and, subsequently, human missions to the Moon with a corresponding team dedicated to mobility system development having been set up at the NASA Glenn Research Center. Given this dynamic environment, it was found timely to establish an expert group on off-the-road mobility as relevant for robotic vehicles that would involve individuals representing the various on-going efforts on the different continents. This was realized through the International Society of Terrain-Vehicle Systems (ISTVS), a research organisation devoted to terramechanics and to the ,science' of off-the-road vehicle development which as a result is just now establishing a Technical Group on Terrestrial and Planetary Rovers. Members represent space-related as well as military research institutes and universities from the US, Germany, Italy, and Japan. The group's charter for 2007 is to define its objectives, functions, organizational structure and recommended research objectives to support planetary rover design and development. Expected areas of activity of the ISTVS-sponsored group include: the problem of terrain specification for planetary rovers; identification of limitations in modelling of rover mobility; a survey of existing rover mobility testbeds; the consolidation of mobility predictive models and their state of validation; sensing and real
Quantum Hamiltonian Complexity
2014-01-01
Constraint satisfaction problems are a central pillar of modern computational complexity theory. This survey provides an introduction to the rapidly growing field of Quantum Hamiltonian Complexity, which includes the study of quantum constraint satisfaction problems. Over the past decade and a half, this field has witnessed fundamental breakthroughs, ranging from the establishment of a "Quantum Cook-Levin Theorem" to deep insights into the structure of 1D low-temperature quantum systems via s...