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1996

The Java Virtual Machine Specification

From the Publisher: The nucleus of the Java 2 platform, the Java virtual machine is the technology that enables the Java 2 platform to host applications on any computer or operating system without rewriting or recompiling. This book was written by those directly responsible for the design and implementation of the Java virtual machine, and is the complete and definitive specification for the technology. It is an essential reference for writers of compilers for the Java programming language and implementors of the Java virtual machine. This second edition specifies the newest version of the Java virtual machine and provides a fascinating view into the inner workings of the Java 2 platform.

2000 - Journal of Econometrics

Does Matching Overcome Lalonde's Critique of Nonexperimental Estimators?

This paper applies cross-sectional and longitudinal propensity score matching estimators to data from the National Supported Work (NSW) Demonstration that have been previously analyzed by LaLonde (1986) and Dehejia and Wahba (1999, 2002). We find that estimates of the impact of NSW based on propensity score matching are highly sensitive to both the set of variables included in the scores and the particular analysis sample used in the estimation. Among the estimators we study, the difference-in-differences matching estimator performs the best. We attribute its performance to the fact that it eliminates potential sources of temporally-invariant bias present in the NSW data, such as geographic mismatch between participants and non-participants and the use of a dependent variable measured in different ways for the two groups. Our analysis demonstrates that while propensity score matching is a potentially useful econometric tool, it does not represent a general solution to the evaluation problem.

1998 - KDD

Integrating Classification and Association Rule Mining

Classification rule mining aims to discover a small set of rules in the database that forms an accurate classifier. Association rule mining finds all the rules existing in the database that satisfy some minimum support and minimum confidence constraints. For association rule mining, the target of discovery is not pre-determined, while for classification rule mining there is one and only one predetermined target. In this paper, we propose to integrate these two mining techniques. The integration is done by focusing on mining a special subset of association rules, called class association rules (CARs). An efficient algorithm is also given for building a classifier based on the set of discovered CARs. Experimental results show that the classifier built this way is, in general, more accurate than that produced by the state-of-the-art classification system C4.5. In addition, this integration helps to solve a number of problems that exist in the current classification systems.

1997

An Arbitrary Lagrangian-Eulerian Computing Method for All Flow Speeds

A new numerical technique is presented that has many advantages for obtaining solutions to a wide variety of time-dependent multidimensional fluid dynamics problems. The method uses a finite difference mesh with vertices that may be moved with the fluid (Lagrangian), be held fixed (Eulerian), or be moved in any other prescribed manner, as in the Arbitrary Lagrangian?Eulerian (ALE) technique. In addition, it employs an implicit formulation similar to that of the Implicit Continuous-fluid Eulerian (ICE) technique, making it applicable to flows at all speeds.This paper describes the basic methodology, presents finite difference approximations, and discusses such matters as stability, accuracy, and zoning. In addition, illustrations are included from a number of representative calculations.

2004 - Journal of Transport Geography

Accessibility evaluation of land-use and transport strategies: review and research directions

A review of accessibility measures is presented for assessing the usability of these measures in evaluations of land-use and transport strategies and developments. Accessibility measures are reviewed using a broad range of relevant criteria, including theoretical basis, interpretability and communicability, and data requirements of the measures. Accessibility impacts of land-use and transport strategies are often evaluated using accessibility measures, which researchers and policy makers can easily operationalise and interpret, such as travelling speed, but which generally do not satisfy theoretical criteria. More complex and disaggregated accessibility measures, however, increase complexity and the effort for calculations and the difficulty of interpretation. The current practice can be much improved by operationalising more advanced location-based and utility-based accessibility measures that are still relatively easy to interpret for researchers and policy makers, and can be computed with state-of-the-practice data and/or land-use and transport models. Research directions towards theoretically more advanced accessibility measures point towards the inclusion of individual's spatial–temporal constraints and feedback mechanisms between accessibility, land-use and travel behaviour. Furthermore, there is a need for theoretical and empirical research on relationships between accessibility, option values and non-user benefits, and the measurement of different components of accessibility.

2015

Land Use, Land-Use Change and Forestry

Land Use, Land-Use Change and Forestry includes research from selected international authors and institutions that consider land use management to be an important aspect in the context of climate change and development. Our team of editors and authors hope to add a valuable contribution to the literature to address global climate change in relation to agricultural-forestry ecosystems and development in vulnerable locations. Land Use, Land Use Change and Forestry book chapters include a wide variety of topics on changes in land use practices, carbon sequestration, forest degradation, as well as polices that affect land use and development. It also includes a description of the current state of land use, land-use change and forestry in South Asian countries (Chapter 1); an evaluation of biodiversity and peoples' willingness to pay (Chapter 2); modelling of carbon sequestration in forests (Chapter 3); trade-off analysis in economic and environmental objectives (Chapter 4); use of radar imagery in detecting forest degradation (Chapter 5); assessment of carbon sequestration in woodlots (Chapter 6); solutions for improved survival of ruminants in arid and semi-arid environments and associated carbon sequestration (Chapter 7); policy interventions for land use changes (Chapter 8); accomplishing land use change from subsistence to commercial farming in Mozambique (Chapter 9); and an international and multi-sectoral approach for partnering to achieve positive agricultural developmental land use change (Chapter 10). Our team of editors, reviewers, and authors are honored to be part of this project; truly an example of international cooperation and articulation within the climate change community. The chapters and authors of Land Use, Land-Use and Forestry were carefully selected through a rigorous peer review process considering publication records, relevant and high quality contributions to this topic, and priming international cooperation. For this book and its contents, the intended audience includes the international climate change community including: contributors to the UNFCCC-IPCC process, policymakers, consultants, project developers, researchers and their institutions. Land Use, Land-Use Change and Forestry aims to be a valuable addition to multidisciplinary and international cooperation efforts (policies, cultural practices, new technologies, and adaptation measures), to development of land use policies, governmental and nongovernmental agencies worldwide and the general public. The editors of Land Use, Land-Use Change and Forestry believe the book is an effective tool to help the international community progress in understanding and management of land use changes in addressing climate change through international collaboration and cooperation.

1989 - Brain : a journal of neurology

The natural history of multiple sclerosis: a geographically based study. I. Clinical course and disability.

The outcome of multiple sclerosis (MS), assessed according to the Kurtzke Disability Status Scale (DSS), was reviewed in 1,099 consecutive patients followed in London, Canada, between 1972 and 1984. A geographically based subgroup of 196 patients representing 90% of Middlesex County MS patients as well as a group of 197 patients seen from onset of disease were separately analysed. The clinical course was progressive from onset in 33% of the total population and in 28% of the Middlesex County subgroup. Of those with duration of 6-10 yrs, 30-40% with initially remitting disease developed progressive MS. The cross-sectional distribution of disability was bimodal with peaks at DSS 1 (no disability) and DSS 6 (assistance required for walking). Actuarial analysis showed that the median time to reach DSS 6 from onset of MS was 14.97 +/- 0.31 yrs in the total population and 9.42 +/- 0.44 yrs in the "seen from onset' subgroup. Survival was minimally altered; 87% of patients followed up to 40 yrs were still alive, although ascertainment of cases with this duration of MS was incomplete. Data describing the rate at which disability develops after the onset of a progressive phase of MS are also presented. The implications of these data in planning and interpretation of clinical therapeutic trials are discussed.

1989 - Brain : a journal of neurology

The natural history of multiple sclerosis: a geographically based study. I. Clinical course and disability.

The outcome of multiple sclerosis (MS), assessed according to the Kurtzke Disability Status Scale (DSS), was reviewed in 1,099 consecutive patients followed in London, Canada, between 1972 and 1984. A geographically based subgroup of 196 patients representing 90% of Middlesex County MS patients as well as a group of 197 patients seen from onset of disease were separately analysed. The clinical course was progressive from onset in 33% of the total population and in 28% of the Middlesex County subgroup. Of those with duration of 6-10 yrs, 30-40% with initially remitting disease developed progressive MS. The cross-sectional distribution of disability was bimodal with peaks at DSS 1 (no disability) and DSS 6 (assistance required for walking). Actuarial analysis showed that the median time to reach DSS 6 from onset of MS was 14.97 +/- 0.31 yrs in the total population and 9.42 +/- 0.44 yrs in the "seen from onset' subgroup. Survival was minimally altered; 87% of patients followed up to 40 yrs were still alive, although ascertainment of cases with this duration of MS was incomplete. Data describing the rate at which disability develops after the onset of a progressive phase of MS are also presented. The implications of these data in planning and interpretation of clinical therapeutic trials are discussed.

2004 - Progress in Planning

GIS-based land-use suitability analysis: a critical overview

There are three main objectives of this monograph: (i) to provide an introduction to geographical information technology along with an historical perspective on the evolving role of Geographic Information Systems (GIS) in planning, (ii) to overview relevant methods and techniques for GIS-based land-use suitability mapping and modeling, and (iii) to identify the trends, challenges and prospects of GIS-based land-use suitability analysis. The monograph focuses on two perspectives of GIS-based land-use suitability analysis: the techno-positivist perspective and the socio-political, public participation perspectives. It is organized into six chapters. After an introductory setting chapter, which defines the scope of land-use suitability analysis, an overview of relevant GIS technology is provided in Chapter 2 . Chapter 3 offers an historical account of the development of GIS. It also discusses the development of GIS in the context of evolving perspectives of planning. Chapter 4 gives an overview of the methods for GIS-based land-use suitability modeling. The overview provides a background against which selected case studies are discussed in Chapter 5 . The concluding chapter summarized the main points of the monographs and discusses problems and prospects for GIS-based land-use suitability analysis.

2003

Artificial Immune Systems: A New Computational Intelligence Approach

Introduction.- Fundamentals of the Immune System.- A Framework for Engineering Artificial Immune Systems.- A Survey of Artificial Immune Systems.- The Immune System in Context with Other Biological Systems.- AIS in Context with Other Computational Intelligence Paradigms.- Case Studies.- Conclusions and Future Trends.- References.- Appendix I: Glossary of Biological Terms.- Appendix II: Pseudocode for Immune Algorithms.- Appendix III: WEB Resources on Artificial Immune Systems. Index.

2010 - GIS '10

Bag-of-visual-words and spatial extensions for land-use classification

We investigate bag-of-visual-words (BOVW) approaches to land-use classification in high-resolution overhead imagery. We consider a standard non-spatial representation in which the frequencies but not the locations of quantized image features are used to discriminate between classes analogous to how words are used for text document classification without regard to their order of occurrence. We also consider two spatial extensions, the established spatial pyramid match kernel which considers the absolute spatial arrangement of the image features, as well as a novel method which we term the spatial co-occurrence kernel that considers the relative arrangement. These extensions are motivated by the importance of spatial structure in geographic data. The methods are evaluated using a large ground truth image dataset of 21 land-use classes. In addition to comparisons with standard approaches, we perform extensive evaluation of different configurations such as the size of the visual dictionaries used to derive the BOVW representations and the scale at which the spatial relationships are considered. We show that even though BOVW approaches do not necessarily perform better than the best standard approaches overall, they represent a robust alternative that is more effective for certain land-use classes. We also show that extending the BOVW approach with our proposed spatial co-occurrence kernel consistently improves performance.

2002 - Environmental Management

Modeling the Spatial Dynamics of Regional Land Use: The CLUE-S Model

Land-use change models are important tools for integrated environmental management. Through scenario analysis they can help to identify near-future critical locations in the face of environmental change. A dynamic, spatially explicit, land-use change model is presented for the regional scale: CLUE-S. The model is specifically developed for the analysis of land use in small regions (e.g., a watershed or province) at a fine spatial resolution. The model structure is based on systems theory to allow the integrated analysis of land-use change in relation to socio-economic and biophysical driving factors. The model explicitly addresses the hierarchical organization of land use systems, spatial connectivity between locations and stability. Stability is incorporated by a set of variables that define the relative elasticity of the actual land-use type to conversion. The user can specify these settings based on expert knowledge or survey data. Two applications of the model in the Philippines and Malaysia are used to illustrate the functioning of the model and its validation.

2003

The Importance of Land-Use Legacies to Ecology and Conservation

Recognition of the importance of land-use history and its legacies in most ecological systems has been a major factor driving the recent focus on human activity as a legitimate and essential subject of environmental science. Ecologists, conservationists, and natural resource policymakers now recognize that the legacies of land-use activities continue to influence ecosystem structure and function for decades or centuries—or even longer—after those activities have ceased. Consequently, recognition of these historical legacies adds explanatory power to our understanding of modern conditions at scales from organisms to the globe and reduces missteps in anticipating or managing for future conditions. As a result, environmental history emerges as an integral part of ecological science and conservation planning. By considering diverse ecological phenomena, ranging from biodiversity and biogeochemical cycles to ecosystem resilience to anthropogenic stress, and by examining terrestrial and aquatic ecosystems in temperate to tropical biomes, this article demonstrates the ubiquity and importance of land-use legacies to environmental science and management.

2004 - Automated Software Engineering

Model Checking Programs

The majority of work carried out in the formal methods community throughout the last three decades has (for good reasons) been devoted to special languages designed to make it easier to experiment with mechanized formal methods such as theorem provers, proof checkers and model checkers. In this paper we will attempt to give convincing arguments for why we believe it is time for the formal methods community to shift some of its attention towards the analysis of programs written in modern programming languages. In keeping with this philosophy we have developed a verification and testing environment for Java, called Java PathFinder (JPF), which integrates model checking, program analysis and testing. Part of this work has consisted of building a new Java Virtual Machine that interprets Java bytecode. JPF uses state compression to handle big states, and partial order and symmetry reduction, slicing, abstraction, and runtime analysis techniques to reduce the state space. JPF has been applied to a real-time avionics operating system developed at Honeywell, illustrating an intricate error, and to a model of a spacecraft controller, illustrating the combination of abstraction, runtime analysis, and slicing with model checking.

2000 - Evolutionary Computation

Architecture for an Artificial Immune System

An artificial immune system (ARTIS) is described which incorporates many properties of natural immune systems, including diversity, distributed computation, error tolerance, dynamic learning and adaptation, and self-monitoring. ARTIS is a general framework for a distributed adaptive system and could, in principle, be applied to many domains. In this paper, ARTIS is applied to computer security in the form of a network intrusion detection system called LISYS. LISYS is described and shown to be effective at detecting intrusions, while maintaining low false positive rates. Finally, similarities and differences between ARTIS and Holland's classifier systems are discussed.

2006 - Journal of Neurology, Neurosurgery & Psychiatry

Epidemiology of benign paroxysmal positional vertigo: a population based study

Objectives: To examine the prevalence and incidence, clinical presentation, societal impact and comorbid conditions of benign paroxysmal positional vertigo (BPPV) in the general population. Methods: Cross-sectional, nationally representative neurotological survey of the general adult population in Germany with a two stage sampling design: screening of 4869 participants from the German National Telephone Health Interview Survey 2003 (response rate 52%) for moderate or severe dizziness or vertigo, followed by validated neurotological interviews (n = 1003; response rate 87%). Diagnostic criteria for BPPV were at least five attacks of vestibular vertigo lasting <1 min without concomitant neurological symptoms and invariably provoked by typical changes in head position. In a concurrent validation study (n = 61) conducted in two specialised dizziness clinics, BPPV was detected by our telephone interview with a specificity of 92% and a sensitivity of 88% (positive predictive value 88%, negative predictive value 92%). Results: BPPV accounted for 8% of individuals with moderate or severe dizziness/vertigo. The lifetime prevalence of BPPV was 2.4%, the 1 year prevalence was 1.6% and the 1 year incidence was 0.6%. The median duration of an episode was 2 weeks. In 86% of affected individuals, BPPV led to medical consultation, interruption of daily activities or sick leave. In total, only 8% of affected participants received effective treatment. On multivariate analysis, age, migraine, hypertension, hyperlipidaemia and stroke were independently associated with BPPV. Conclusion: BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact and medical costs.

2006 - Journal of Computer Applications

Privacy preserving association rule mining in vertically partitioned data

A privacy preserving association rule mining algorithm was introduced.This algorithm preserved privacy of individual values by computing scalar product.Meanwhile the algorithm of computing scalar product was given and the security was analyzed.

1999 - KDD '99

Mining association rules with multiple minimum supports

Association rule mining is an important model in data mining. Its mining algorithms discover all item associations (or rules) in the data that satisfy the user-specified minimum support (minsup) and minimum confidence (minconf) constraints. Minsup controls the minimum number of data cases that a rule must cover. Minconf controls the predictive strength of the rule. Since only one minsup is used for the whole database, the model implicitly assumes that all items in the data are of the same nature and/or have similar frequencies in the data. This is, however, seldom the case in reallife applications. In many applications, some items appear very frequently in the data, while others rarely appear. If minsup is set too high, those rules that involve rare items will not be found. To find rules that involve both frequent and rare items, minsup has to be set very low. This may cause combinatorial explosion because those frequent items will be associated with one another in all possible ways. This dilemma is called the rare item problem. This paper proposes a novel technique to solve this problem. The technique allows the user to specify multiple minimum supports to reflect the natures of the items and their varied frequencies in the database. In rule mining, different rules may need to satisfy different minimum supports depending on what items are in the rules. Experiment results show that the technique is very effective.

2005 - POPL '05

The Java memory model

This paper describes the new Java memory model, which has been revised as part of Java 5.0. The model specifies the legal behaviors for a multithreaded program; it defines the semantics of multithreaded Java programs and partially determines legal implementations of Java virtual machines and compilers.The new Java model provides a simple interface for correctly synchronized programs -- it guarantees sequential consistency to data-race-free programs. Its novel contribution is requiring that the behavior of incorrectly synchronized programs be bounded by a well defined notion of causality. The causality requirement is strong enough to respect the safety and security properties of Java and weak enough to allow standard compiler and hardware optimizations. To our knowledge, other models are either too weak because they do not provide for sufficient safety/security, or are too strong because they rely on a strong notion of data and control dependences that precludes some standard compiler transformations.Although the majority of what is currently done in compilers is legal, the new model introduces significant differences, and clearly defines the boundaries of legal transformations. For example, the commonly accepted definition for control dependence is incorrect for Java, and transformations based on it may be invalid.In addition to providing the official memory model for Java, we believe the model described here could prove to be a useful basis for other programming languages that currently lack well-defined models, such as C++ and C#.

2007 - Neural networks : the official journal of the International Neural Network Society

An experimental unification of reservoir computing methods

Three different uses of a recurrent neural network (RNN) as a reservoir that is not trained but instead read out by a simple external classification layer have been described in the literature: Liquid State Machines (LSMs), Echo State Networks (ESNs) and the Backpropagation Decorrelation (BPDC) learning rule. Individual descriptions of these techniques exist, but a overview is still lacking. Here, we present a series of experimental results that compares all three implementations, and draw conclusions about the relation between a broad range of reservoir parameters and network dynamics, memory, node complexity and performance on a variety of benchmark tests with different characteristics. Next, we introduce a new measure for the reservoir dynamics based on Lyapunov exponents. Unlike previous measures in the literature, this measure is dependent on the dynamics of the reservoir in response to the inputs, and in the cases we tried, it indicates an optimal value for the global scaling of the weight matrix, irrespective of the standard measures. We also describe the Reservoir Computing Toolbox that was used for these experiments, which implements all the types of Reservoir Computing and allows the easy simulation of a wide range of reservoir topologies for a number of benchmarks.

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