bluuebunny/crossref_metadata_2025_split huggingface dataset:
NORMAL FORMS AND LORENZ ATTRACTORS
Authors: SHIL'NIKOV A. L. , SHIL'NIKOV L. P. , TURAEV D. V. 
Published: November 2004

Normal forms for eleven cases of bifurcations of codimension-3 are considered, basically, in systems with a symmetry, which can be reduced to one of the two three-dimensional systems. The first system is the well-known Lorenz model in a special notation, the second is the Shimizu-Morioka model. In contrast with two-dimensional normal forms which admit, in principle, a complete theoretical study, in three-dimensional systems such analysis is practically impossible, except for particular parameter values when a system is close to an integrable system. Therefore, the main method of the investigation is qualitatively-numerical. In that sense, a description of principal bifurcations which lead to the appearance of the Lorenz attractor is given for the models above, and the boundaries of the regions of the existence of this attractor are selected. We pay special attention to bifurcation points corresponding to a formation of a homoclinic figure-8 of a saddle with zero saddle value and that of a homoclinic figure-8 with zero separatrix value. In L. P. Shil'nikov [1981], it was established that these points belong to the boundary of the existence of the Lorenz attractor. In the present paper, the bifurcation diagrams near such points for the symmetric case are given and a new criterion of existence of the nonorientable Lorenz is also suggested.
ON THE PRESENCE OF NORMALLY ATTRACTING MANIFOLDS CONTAINING PERIODIC OR QUASIPERIODIC ORBITS IN COUPLED MAP LATTICES
Authors: GIBERTI CLAUDIO , VERNIA CECILIA 
Published: November 2004

The significant presence of normally attracting invariant manifolds, formed by closed curves or two-tori, is investigated in two-dimensional lattices of coupled chaotic maps. In the case of a manifold formed by closed curves, it contains symmetrically placed periodic orbits, with the property of a very weak hyperbolicity along the manifold itself. The resulting dynamics is an extremely slow relaxation to periodic behavior. Analogously, a manifold consisting of two-tori includes very weakly hyperbolic periodic (or quasiperiodic) orbits, which in this case also implies quite a long time before any solution approaches periodicity or quasiperiodicity. The normally attracting manifolds and the contained weak attractors can undergo several global bifurcations. Some of them, including saddle-node bifurcation, period-doubling and Hopf bifurcation, are illustrated. Almost all the asymptotic solutions that we discuss have flat rows or flat columns, which means that they can occur also in one-dimensional lattices.
A CONVEX HULL ALGORITHM FOR POINTS WITH APPROXIMATELY KNOWN POSITIONS
Authors: FRANCIOSA PAOLO GIULIO , GAIBISSO CARLO , GAMBOSI GIORGIO , TALAMO MAURIZIO 
Published: November 2004

We consider the problem of deriving good approximations of the convex hull of a set of points in the plane in the realistic case that only arbitrary finite approximations of the real valued coordinates can be known. In particular, the algorithm we introduce derives sequences of improved certified approximations converging to the exact solution, at the same time allowing the insertion of new points to the problem instance. The complexity analysis of the algorithm is performed by referring to a suitable computation model, based on a RAM with logarithmic costs, and the derived space and time bounds are shown to be competitive with respect to current off-line algorithms.
N-DIMENSIONAL GENERALIZED COMBINATORIAL MAPS AND CELLULAR QUASI-MANIFOLDS
Authors: LIENHARDT PASCAL 
Published: November 2004

The scope of this work is Geometric Modeling. We study the representation and the construction of subdivisions of quasi-manifolds, using a topology-based approach. Quasi-manifolds are here defined as a subset of pseudo-manifolds, which are well-known objects in Algebraic Topology. N-dimensional generalized maps (resp. n-dimensional maps) are combinatorial models defined for representing the topology of subdivisions of orientable or non-orientable quasi-manifolds with or without boundaries (resp. orientable quasi-manifolds without boundaries). In this paper, we define the models, main related notions and properties as cells, boundaries, duality, orientability, Euler characteristic. Basic operations are proposed for handling the models. We also show the correspondence between the combinatorial models and combinatorial cellular quasi-manifolds, here defined as combinatorial simplicial quasi-manifolds to which a structure into cells is added. This correspondence establishes that the models are rigorous and unambiguous ones. Moreover, the definitions of the models and the related notions and operations are quite simple, and they can be easily implemented and used in geometric modellers.
GLOBAL WEAK SOLUTIONS OF THE ONE-DIMENSIONAL HYDRODYNAMIC MODEL FOR SEMICONDUCTORS
Authors: JOCHMANN F. 
Published: November 2004

The existence of a global weak solution of the one-dimensional hydrodynamic model for semiconductors is proved by the method of artificial viscosity and the theory of compensated compactness. The system is first regularized and global viscosity-solutions are constructed. Letting the viscosity-parameter tend to zero, we obtain a sequence of viscosity-solutions converging in L∞-weak* to a weak solution of the one-dimensional p-system from isoentropic gas dynamics with an electric field term and momentum relaxation. Since the equations are nonlinear and the convergence is only weak, the theory of Young-measures and compensated compactness is applied to obtain a weak solution of the limit problem.
VISUALIZING DYNAMIC ARTIFICIAL INTELLIGENCE ALGORITHMS AND APPLICATIONS
Authors: PERLIN MARK W. 
Published: November 2004

Visualization is an important component of modern computing. By animating the course of an algorithm’s temporal execution, many key features can be elucidated. We have developed a general framework, termed Call-Graph Caching (CGC), for automating the construction of many complex AI algorithms. By incorporating visualization into CGC interpreters, principled animations can be automatically displayed as AI computations unfold. (1) Systems that support the automatic animation of AI algorithms must address these three design issues: (2) How to represent AI data structures in a general, uniform way that leads to perspicuous animation and efficient redisplay. (3) How to coordinate the succession of graphical events. (4) How to partition AI graphs to provide for separate, uncluttered displays. CGC provides a natural and effective solution to all these concerns. (5) We describe the CGC method, including detailed examples, and motivate why CGC works well for animation. We discuss the CACHE system, our CGC environment for AI algorithm animation. We demonstrate the animation of several AI algorithms – RETE match, linear unification, arc consistency, chart parsing, and truth maintenance – all of which have been implemented in CACHE. Finally, we discuss the application of these methods to interactive interfaces for intelligent systems, using molecular genetics as an example domain.
TEMPERLEY-LIEB ALGEBRAS FOR NON-PLANAR STATISTICAL MECHANICS — THE PARTITION ALGEBRA CONSTRUCTION
Authors: MARTIN PAUL 
Published: November 2004

We give the definition of the Partition Algebra Pn(Q). This is a new generalisation of the Temperley–Lieb algebra for Q-state n-site Potts models, underpinning their transfer matrix formulation on arbitrary transverse lattices. In Pn(Q) subalgebras appropriate for building the transfer matrices for all transverse lattice shapes (e.g. cubic) occur. For [Formula: see text] the Partition algebra manifests either a semi-simple generic structure or is one of a discrete set of exceptional cases. We determine the Q-generic and Q-independent structure and representation theory. In all cases (except Q = 0) simple modules are indexed by the integers j ≤ n and by the partitions λ ˫ j. Physically they may be associated, at least for sufficiently small j, to 2j 'spin' correlation functions. We exhibit a subalgebra isomorphic to the Brauer algebra.
LISSAJOUS KNOTS
Authors: BOGLE M. G. V. , HEARST J. E. , JONES V. F. R. , STOILOV L. 
Published: November 2004

A Lissajous knot is defined to be one isotopic to a knot which admits a parametrization (for 0≤t≤2π) [Formula: see text] Motivation for considering Lissajous knots came originally from the study of DNA molecular configurations. We will show that a Lissajous knot necessarily has Kervaire invariant zero so that the trefoil, figure-8 and the (2,5) torus knot are not Lissajous. The knot 52 can be realized with nx = 2, ny = 3, nz = 7.
PUTTING MANAGEMENT MODELS ON THE MANAGER’S DESKTOP
Authors: SILVERT WILLIAM 
Published: November 2004

One of the greatest problems facing theoretical scientists and modellers is the difficulty of presenting results to managers in a form that can be understood and utilized by them while retaining as much as possible of the scientific content. Many managers have limited scientific expertise and they are often unfamiliar with theoretical approaches. They are also reluctant to share their decision-making responsibilities with scientists, who may not be familiar with all the factors they have to deal with. This often makes it difficult for scientific advisors to function effectively. An alternative is to use expert systems technology to let managers access the scientific expertise relevant to the decision-making process without requiring direct personal interaction with scientific advisors. This is particularly appropriate for environmental management situations where managers in remote locations may not have easy access to scientists in relevant fields. We have therefore been developing a Decision Support System (DSS) as a tool for communicating scientific advice to managers. This paper addresses the general issues behind using Decision Support Systems in this way and discusses some of the problems involved. Although a computer program cannot be expected to represent more than a fraction of the expertise of real scientists, the DSS approach appears to have several advantages; these include the ability to deliver a degree of expertise in remote and isolated regions, and, perhaps most important, a chance for managers to access scientific resources in a private environment which lets them explore various options without having to justify their eventual actions to scientists who may not fully appreciate all the pressures which bear on their decisions.
COMPUTER SIMULATIONS OF FRACTAL SURFACES: APPLICATION IN ADSORPTION
Authors: DOBRESCU GIANINA , RUSU M. , VASS M. 
Published: November 2004

A computer program which is able to simulate adsorption on fractal surfaces was developed. The fractal surfaces are generated as Takagi surfaces. The computer program is based on a DLA-algorithm. Adsorption was simulated in different conditions: 1. equivalent active sites (homogeneous surfaces); 2. active sites with different adsorption probabilities; the probability associated with every active site is computed using a van der Waals potential. Our simulation allows us to explore the actual structure of the gas-solid interface and to study the sensitivity to energetic disorder. The fractal dimension of gas-solid interface vs. adsorption coverage curves are computed.
A FRACTAL MODEL FOR SEISMICITY AT IZU-TOKAI REGION, CENTRAL JAPAN
Authors: BODRI B. 
Published: November 2004

Fractal approach has been applied to investigate regional seismicity at the Izu peninsula—Tokai area, Central Japan. The frequency-magnitude distribution of earthquakes, distribution of epicenters, origin times of earthquakes, the fracture fault system in the region have been considered, and the fractal dimensions corresponding to them were calculated. A good correspondence in the fractal dimension values was found. The frequency-magnitude distribution in the area shows a fractal dimension of 1.28, whilst D=1.15±0.18 is representative of the geometry of the distribution of earthquake epicenters. The fractal dimension of faults for the Izu peninsula is found to be 1.16±0.04, and in the whole Izu-Tokai region, values 1.1<D<1.3 are characteristic. The temporal distribution of earthquakes yields a fractal dimension of 0.51±0.03, which indicates a relatively weak clustering of events in time. Independent autocorrelation analysis also shows that the earthquakes in the area of study occur to a large extent statistically independent. The general conclusion is that crustal deformation in the Izu-Tokai region occurs on a scale-invariant matrix faults. The behavior of the system is controlled by a single parameter, the fractal of dimension.
THE RISK MANAGEMENT OF THE ENTREPRENEUR: AN ECONOMIC-PSYCHOLOGICAL PERSPECTIVE
Authors: DELMAR FREDERIC 
Published: November 2004

The risk management of the entrepreneur is an important factor that can explain the success or failure of a business venture. The problem of risk management is here approached from an economic-psychological perspective. In this study the risk management of entrepreneurs is compared. The entrepreneurs are divided into three subgroups; super-entrepreneurs, small business owner-managers, and failed entrepreneurs (who went bankrupt). In this study, some interesting results are found. There seems to be some differences in how the categories of entrepreneurs manage risk. An entrepreneur’s acceptance of uncertainty, ability to manage risk and perception of the situation are discussed in this paper. In general, the results show the super-entrepreneur as risk aversive and highly motivated, and the success of the business as attributable to this combination. The small business owner-manager prefers control to growth. The failed entrepreneur does not use the social network and has no buffer for problems.
ALGORITHMS TO REALIZE AN ARBITRARY BPC PERMUTATION IN CHORDAL RING NETWORKS WITH FAILURES
Authors: MASUYAMA HIROSHI , MASUYAMA ETSUKO 
Published: November 2004

A family of regular graphs of degree 3, called chordal rings is presented as a possible candidate for the implementation of a distributed system and for fault-tolerant architectures. The symmetry of graphs makes it possible to determine message routing by using a simple distributed algorithm. Arbitrary data permutations are generally accomplished by sorting. For certain classes of permutations, however, there exist algorithms that are more efficient than the best sorting algorithm. One such class is the Bit Permute Complement (BPC) class of permutations. In this paper, we first develop algorithms requiring two token storage registers in each node to realize an arbitrary BPC permutation. We next evaluate its ability to realize BPC permutations in networks of arbitrary size by estimating the number of required routing steps when a single fault is present and when not.
Remotely Sensed Microphysical and Thermodynamic Properties of Nonuniform Water Cloud Fields
Authors: Harshvardhan  , Guo Guang , Green Robert N. , Qu Zheng , Nakajima Takashi Y. 
Published: November 2004

Abstract
Visible and near-infrared reflected radiances have been used to estimate the cloud optical depth and effective radius of cloud-filled global area coverage (GAC) pixels from the Advanced Very High Resolution Radiometer (AVHRR) for two cases in the North Atlantic Ocean. One is representative of clouds having low concentrations of cloud condensation nuclei (CCN), while the other is an example of maritime clouds forming in continental air, in this case, intruding from Europe around a cutoff low pressure system. It is shown that an estimate of the cloud drop concentration can be obtained from remotely sensed cloud radiative properties and standard meteorological analyses. These concentrations show very clearly the influence of enhanced CCN on cloud microphysics. However, conclusions regarding the indirect radiative effect of aerosol on cloud must wait for the development of a framework for analyzing changes in cloud liquid water path (LWP). It is shown that estimates of LWP are greatly influenced by the scheme that is used to identify cloudy pixels at the AVHRR GAC resolution. Application of a very strict thermal channel spatial coherence criterion for identifying cloud-filled pixels yields mean LWP estimates for cloudy pixels alone that are 40%–75% higher than mean LWP estimates for the much larger sample of possibly cloudy pixels identified by a reflectance threshold criterion.
Imparting Self-Control Skills to Decrease Aggressive Behavior in a 12-Year-Old Boy
Authors: Ronen Tammie 
Published: November 2004

•Summary: This paper presents the case of a 12-year-old boy with oppositional defiant disorder (ODD) who demonstrated no interest in participating in therapy. The aims of the paper were to present a multiple therapy design as an effective measurement for social workers to use in their regular intervention process; to learn about the relative effectiveness of three common methods for addressing ODD (behavior therapy being used in teacher supervision and parental counseling and cognitive therapy being used in the child’s individual therapy); and to present a self-control model for improving the child’s behavior. •Findings: The case study pointed to the efficacy of the self-control model for helping the child change. Therapy facilitated a significant decrease in the child’s disruptive behavior as well as a significant increase in the child’s self-control and social interaction. Also, the case study presented the feasibility of the single case design as an effective way for social workers to assess and evaluate their intervention. •Applications: The presented case study highlighted the ability of social workers: 1. to supervise parents and teachers as important change agents in the child’s environment; 2. to use the single case design in daily intervention; and 3. to utilize cognitive behavioral therapy as an effective method for change. The efficacy of the intervention pinpointed the need to apply the proposed methods for other problems as well.
Relations in Foster Care
Authors: Mosek Atalia 
Published: November 2004

•Summary: This article explores the values, knowledge, policy and practice of three different programs of foster care in Israel and their implications for the experiences of all involved: children, parents, foster parents and social workers. •Findings: An innovative methodology is used, whereby social work students collect data. Analysis of this qualitative data collected through semi-structured interviews clarifies the issues that are of major concern for foster children, parents, foster parents and foster workers. A connection is made between the service models that support detached, complementary or reciprocal relations and experiences in care. •Applications: The article established the viewpoint that foster care is a creation of a new familial system that needs to deal with issues of power and create reciprocal relations amongst its partners. The conditions necessary for successful care are highlighted.
Ethical Practice in the Contemporary Human Services
Authors: Lonne Bob , Mcdonald Catherine , Fox Tricia 
Published: November 2004

•Summary: This paper examines the findings of an exploratory study of emerging ethical issues and practices reported by a sample of human service managers and practitioners in public and non-profit agencies in Queensland, Australia. •Findings: The contemporary context in which human services are delivered in Western societies is characterized by increased marketization, contractualism and managerialist practices, all of which entail different ethical values from those traditionally embraced by the social work profession. Utilizing qualitative and quantitative methodologies, this research identifies current and emerging challenges to ethical practice and existing organizational responses to it. Widespread concern about the negative aspects of changed structural arrangements on ethical practice in the contemporary human services is highlighted. Differences in the ways in which organizations and practitioners are responding to these changes are examined. The limitations of existing approaches and ethics codes are noted. •Applications: Implications for organizations, practitioners and educators are explored, and more pro-active management and training strategies are advocated. Further research is required to identify the often-understated negative effects on ethical practice of the market-based reforms of human service structures and processes.
Congenital and Acquired Thrombocytopenia
Authors: Cines Douglas B. , Bussel James B. , McMillan Robert B. , Zehnder James L. 
Published: November 2004

Abstract
The diagnosis and management of thrombocytopenia is a growing component in the practice of hematology. The frequency with which hematologists are called in consultation for thrombocytopenia continues to increase with the advent of routine automated platelet determinations and the introduction of new medications. For most patients, such as those with inherited and auto-immune thrombocytopenia, emphasis is focused on efforts to treat or forestall bleeding without excess drug-induced toxicity or burden to the patient. However, in disorders such as heparin-induced thrombocytopenia (HIT), avoidance of thrombotic complications is the key to management. In this chapter, we provide the pediatric and adult hematologist with new insights into the pathogenesis and recognition of congenital inherited thrombocytopenias (CTP), a hitherto difficult to comprehend constellation of clinical entities. We also highlight new approaches to the diagnosis and treatment of two of the more common thrombocytopenic conditions encountered in practice, autoimmune or idiopathic thrombocytopenic purpura (ITP) and HIT.
In Section I, Dr. James Bussel discusses CTPs and their distinction from childhood ITP. He emphasizes the clinical features that enable the pediatrician and hematologist to suspect the diagnosis of CTP and those that are of use to subcategorize the various entities, where possible. He also emphasizes newer molecular markers that afford definitive diagnosis in some cases and provide insight into platelet production. This section highlights the characteristic associated findings and differences in the natural history and approaches to management of the various entities.
In Section II, Dr. Robert McMillan discusses adult chronic ITP. He revisits the utility of platelet antibody determination in diagnosis and review new insights into pathogenesis. The role of Helicobacter pylori infection and the timing of splenectomy in the management of acute and emergent ITP are examined. New insights into the natural history of ITP post-splenectomy and management strategies for patients with severe, chronic, refractory ITP are discussed.
In Section III, Dr. James Zehnder updates us on HIT. He emphasizes new insights into the clinical presentation and pathogenesis of this condition. He critically reviews the utility of laboratory testing for heparin-dependent antibodies. Recent studies on the use of direct thrombin inhibitors are examined and the management of cardiopulmonary bypass surgery in patients with HIT is discussed.