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This commentary on John Symons' and Jack Horner's paper, besides sharing its main argument, challenges the authors' statement that there is no effective method to evaluate software-intensive systems as a distinguishing feature of software intensive science. It is underlined here how analogous methodological limitations characterise the evaluations of empirical systems in non-software intensive sciences. The authors' claim that formal methods establish the correctness of computational models rather than of the represented programme is here compared with the empirical adequacy problem typifying the model-based reasoning approach in physics, and the remark that testing all the paths of a software-intensive system is unfeasible is related to the enumerative induction problem in the justification of empirical law-like hypotheses in non-software intensive sciences. [ABSTRACT FROM AUTHOR]

The recent adoption of deep learning-based models for the processing and coding of multimedia signals has brought noticeable gains in performance, which have established deep learning-based solutions as the uncontested state-of-the-art both for computer vision tasks, targeting machine consumption, as well as, more recently, coding applications, targeting human visualization. Traditionally, applications requiring both coding and computer vision processing require first decoding the bitstream and then applying the computer vision methods to the decompressed multimedia signals. However, the adoption of deep learning-based solutions enables the use of compressed domain computer vision processing, with gains in performance and computational complexity over the decompressed domain approach. For point clouds (PCs), these gains have been demonstrated in the single available compressed domain computer vision processing solution, named Compressed Domain PC Classifier, which processes JPEG Pleno PC coding (PCC) compressed streams using a PC classifier largely compatible with the state-of-the-art spatial domain PointGrid classifier. However, the available Compressed Domain PC Classifier presents strong limitations by imposing a single, specific input size which is associated to specific JPEG Pleno PCC configurations; this limits the compression performance as these configurations are not ideal for all PCs due to their different characteristics, notably density. To overcome these limitations, this paper proposes the first Adaptive Compressed Domain PC Classifier solution which includes a novel adaptive bridge model that allows to process the JPEG Pleno PCC encoded bit streams using different coding configurations, now maximizing the compression efficiency. Experimental results show that the novel Adaptive Compressed Domain PC Classifier allows JPEG PCC to achieve better compression performance by not imposing a single, specific coding configuration for all PCs, regardless of its different characteristics. Moreover, the added adaptability power can achieve slightly better PC classification performance than the previous Compressed Domain PC Classifier and largely better PC classification performance (and lower number of weights) than the PointGrid PC classifier working in the decompressed domain. [ABSTRACT FROM AUTHOR]

Agent-based modelling allows researchers to build artificial pastoral systems that are spatially explicit and allow for the examination of complex interactions between households, herds, and rangelands over long time periods. However, agent-based modelling also necessarily reduces the complexity of the pastoral systems. The question that we examine in this paper is how researchers model pastoral systems and what artificial pastoral systems they create. To answer that question, we systematically reviewed 35 agent-based modelling studies of pastoral systems. We examined how the studies describe the focal pastoral system, how the focal system is represented in a conceptual model, implemented in computer code, and how it emerges as an artificial pastoral system from the simulations. Our review indicates that most models are built by interdisciplinary teams, integrated into empirical studies of pastoral systems, and use a specific pastoral system as its focal system. The research problems explored in the models range from resource management, wealth dynamics, herd demography, sustainability, adaptation, mobility, and conflict. The artificial pastoral systems that emerge from these agent-based modelling studies mostly confirm current theoretical understandings that are based on empirical studies of pastoral systems. There are a few emergent patterns that have not been validated extensively in empirical studies. We conclude with a discussion of the theoretical, methodological, and practical implications of using agent-based models to create artificial pastoral systems. [ABSTRACT FROM AUTHOR]

This special section is devoted to a selection of papers that appeared originally in the Proceedings of TACAS 2001, the 7th International Conference on Tools and Algorithms for the Construction and Analysis of Systems [1] which took place in Genova, Italy in April 2001 as a constituent event of the European joint conferences on theory and Practice of Software. All papers present approaches, tools and algorithms that aim at extending the scope of formal techniques (coverage of systems specifications, data structures, size, and their trade-offs) for validation, verification, and testing of software systems. They are by no means a complete account of the numerous ways in which real software and software systems may become subject to rigorous investigation, but they provide an interesting sampling of novel approaches towards scalability of formal methods-based validation. [ABSTRACT FROM AUTHOR]

We seek a unified and distinctive citation description of both journals and individuals. The journal impact factor has a restrictive definition that constrains its extension to individuals, whereas the h-index for individuals can easily be applied to journals. Going beyond any single parameter, the shape of each negative slope Hirsch curve of citations vs. rank index is distinctive. This shape can be described through five minimal parameters or 'flags': the h-index itself on the curve; the average citation of each segment on either side of h; and the two axis endpoints. We obtain the five flags from real data for two journals and 10 individual faculty, showing they provide unique citation fingerprints, enabling detailed comparative assessments. A computer code is provided to calculate five flags as the output, from citation data as the input. Since papers (citations) can form nodes (links) of a network, Hirsch curves and five flags could carry over to describe local degree sequences of general networks. [ABSTRACT FROM AUTHOR]

Alan Turing's "Computing Machinery and Intelligence," published in 1950, is one of the founding texts in the field of artificial intelligence (AI), although the term was not coined until 1958, 4 years after his death. From the treatment of human intelligence as computational and the brain as mechanical to the comparison of animals to machines to the disregard for the materiality of computers to programming as a stand-in for procreation to fiction-inspired science, many of the core tenets that have shaped the field of AI have their origins in Turing's paper. A close analysis of the paper exposes some of the problematic logic underlying these tenets that are now proving damaging for both society and the planet. [ABSTRACT FROM AUTHOR]

Software engineering (SE) research should be relevant to industrial practice. There have been regular discussions in the SE community on this issue since the 1980's, led by pioneers such as Robert Glass. As we recently passed the milestone of "50 years of software engineering", some recent positive efforts have been made in this direction, e.g., establishing "industrial" tracks in several SE conferences. However, many researchers and practitioners believe that we, as a community, are still struggling with research relevance and utility. The goal of this paper is to synthesize the evidence and experience-based opinions shared on this topic so far in the SE community, and to encourage the community to further reflect and act on the research relevance. For this purpose, we have conducted a Multi-vocal Literature Review (MLR) of 54 systematically-selected sources (papers and non peer-reviewed articles). Instead of relying on and considering the individual opinions on research relevance, mentioned in each of the sources, the MLR aims to synthesize and provide the "holistic" view on the topic. The highlights of our MLR findings are as follows. The top three root causes of low relevance, discussed in the community, are: (1) Researchers having simplistic views (or wrong assumptions) about SE in practice; (2) Lack of connection with industry; and (3) Wrong identification of research problems. The top three suggestions for improving research relevance are: (1) Using appropriate research approaches such as action-research; (2) Choosing relevant (practical) research problems; and (3) Collaborating with industry. By synthesizing all the discussions on this important topic so far, this paper aims to encourage further discussions and actions in the community to increase our collective efforts to improve the research relevance. Furthermore, we raise the need for empirically-grounded and rigorous studies on the relevance problem in SE research, as carried out in other fields such as management science. [ABSTRACT FROM AUTHOR]

Regression testing is a means to assure that a change in the software, or its execution environment, does not introduce new defects. It involves the expensive undertaking of rerunning test cases. Several techniques have been proposed to reduce the number of test cases to execute in regression testing, however, there is no research on how to assess industrial relevance and applicability of such techniques. We conducted a systematic literature review with the following two goals: firstly, to enable researchers to design and present regression testing research with a focus on industrial relevance and applicability and secondly, to facilitate the industrial adoption of such research by addressing the attributes of concern from the practitioners' perspective. Using a reference-based search approach, we identified 1068 papers on regression testing. We then reduced the scope to only include papers with explicit discussions about relevance and applicability (i.e. mainly studies involving industrial stakeholders). Uniquely in this literature review, practitioners were consulted at several steps to increase the likelihood of achieving our aim of identifying factors important for relevance and applicability. We have summarised the results of these consultations and an analysis of the literature in three taxonomies, which capture aspects of industrial-relevance regarding the regression testing techniques. Based on these taxonomies, we mapped 38 papers reporting the evaluation of 26 regression testing techniques in industrial settings. [ABSTRACT FROM AUTHOR]

Reliable and reproducible research is an important cornerstone of science, and version control systems not only make reproducible research possible in a rapid and easy way, but also provide a way of collaborating with co-authors. The purpose of this methodological paper is to present Git, a very successful version control system and how it can be used by economists working together on their papers and the accompanying computer code. Version control systems also make sharing the findings with the rest of the scientific community more easy and streamlined. To understand how version control systems came to be, one must be familiar with the history of free software. In the introduction, I will present free software and its philosophy and show how version control systems make free software possible. In the second section I present Git which is a widely used version control system. In the third section I show a basic usage of Git. In the fourth section, I conclude. [ABSTRACT FROM AUTHOR]

This paper proposes a synchronous measurement system of four position-independent geometric errors (PIGEs) and two position-dependent geometric errors (PDGEs) for the rotary axis in five-axis machine tools. The measuring instruments used in this system include a touch-trigger probe and two standard calibration spheres. The main contribution of this paper simultaneously and directly measures four PIGEs and two PDGEs (axial and angular positioning errors) through only one measuring process. It is expected to improve the deficiencies of previous studies measuring PIGEs and PDGEs separately. The geometric errors of the C-axis of a mill-turn machine tool MT-540 were analyzed. The calculation process includes the establishment of the mathematical model of the machine and geometric error equations. The least squares method was used to solve the linear overdetermined system and calculate the values of the geometric errors. Before solving the geometric errors, the accuracy of the calculation process was verified by using the simulated method. The simulation results also confirm the feasibility of this measurement system. Then the data obtained from the experiments were used to calculate the geometric errors of the machine tool. During the experiments, the calibration procedure of the touch-trigger probe was calibrated. After the calibration procedure was completed, the mechanical coordinate values of the two standard calibration balls were measured. The geometric error equations were programmed on a computer, and the data of calibration spheres obtained from the experimental measurements were substituted into the program to calculate the four PIGEs and two PDGEs. [ABSTRACT FROM AUTHOR]

This article introduces the articles in volume 31, number 3 of the "International Journal of Parallel Programming". The volume is devoted to a collection of papers on the parallel programming API OpenMP. The papers have been selected from the presentations at the second International Workshop on OpenMP: Experiences and Implementations WOMPEI2002, as part of ISHPC-IV International Symposium on High-Performance Computing, that took place in Kansai Science City in Japan. This collection includes 4 papers from some of the active research groups in OpenMP-related issues and its evaluation. It is the author's hope that the papers in the collection will prove to be interesting and useful to readers, and that the issues raised will stimulate many of them to further research on OpenMP.

Slope stability is an important problem in the field of geotechnical engineering. In order to widen the application range of upper bound limit analysis in engineering practice, this paper analyzes layered distribution characteristics of slope soil and establishes horizontal layers slope failure mechanism which satisfies the separation of velocity, then proposes calculation method for external force power and internal energy dissipation power using discrete algorithm. On this basic, this paper prepares cycle flow of slope stability analysis by upper bound limit principle and strength reduction principle, and develops stability analysis system by computer programming technology. Taking typical mine excavation slope as engineering background and calculates stability coefficient corresponding to different slope angles and evaluate analysis results accuracy by combining with limit equilibrium method. The results show that the stability coefficient error rate of two methods is between 3 and 5%, which can satisfy requirements of engineering practice. Moreover, stability coefficient obtained by upper bound limit analysis is an upper limit solution, and calculation errors are easy to eliminate, so it has certain applicability in slope engineering practice. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented which discusses various reports within the issue on topics including decomposition-based packet classification mechanism, core-distribution scheduler, and parallel multiple approach based on implicitly restarted Arnoldi method.

Research studies in software maintenance are notoriously hard to reproduce due to lack of datasets, tools, implementation details (e.g., parameter values, environmental settings) and other factors. The progress in the field is hindered by the challenge of comparing new techniques against existing ones, as researchers have to devote a large portion of their resources to the tedious and error-prone process of reproducing previously introduced approaches. In this paper, we address the problem of experiment reproducibility in software maintenance and provide a long-term solution towards ensuring that future experiments will be reproducible and extensible. We conducted a preliminary mapping study of a number of representative maintenance techniques and approaches and implemented them as a set of experiments and a library of components that we make publicly available with TraceLab, called the Component Library. The goal of these experiments and components is to create a body of actionable knowledge that would (i) facilitate future research and (ii) allow the research community to contribute to it as well. In addition, to illustrate the process of using and adapting these techniques, we present an example of creating new techniques based on existing ones, in order to produce improved results. [ABSTRACT FROM AUTHOR]

This article introduces the themes of the papers featured in the April 2000 special issue of the "International Journal of Parallel Programming." The first paper describes a loop transformation algorithm. The second paper proposes a new way to develop concurrent programs, called hypersequential programming. The third paper introduces a workstation cluster implementing a distributed shared-memory mechanism. Lastly, the fourth paper discusses issues of multilevel parallelization and how they affect design of parallelizing compilers.

Apart from good instructional design and delivery, effective intervention is another key to strengthen student academic performance. However, intervention has been recognized as a great challenge. Most instructors struggle to identify at-risk students, determine a proper intervention approach, trace and evaluate whether the intervention works. This process requires extensive effort and commitment, which is impractical especially for large classes with few instructors. This paper proposes a platform, namely i-Ntervene, that integrates Learning Management System (LMS) automatic code grader, and learning analytics features which can empower systematic learning intervention for large programming classes. The platform supports instructor-pace courses on both Virtual Learning Environment (VLE) and traditional classroom setting. The platform iteratively assesses student engagement levels through learning activity gaps. It also analyzes subject understanding from programming question practices to identify at-risk students and suggests aspects of intervention based on their lagging in these areas. Students' post-intervention data are traced and evaluated quantitatively to determine effective intervention approaches. This evaluation method aligns with the evidence-based research design. The developed i-Ntervene prototype was tested on a Java programming course with 253 first-year university students during the Covid-19 pandemic in VLE. The result was satisfactory, as the instructors were able to perform and evaluate 12 interventions throughout a semester. For this experimental course, the platform revealed that the approach of sending extrinsic motivation emails had more impact in promoting learning behavior compared to other types of messages. It also showed that providing tutorial sessions was not an effective approach to improving students' subject understanding in complex algorithmic topics. i-Ntervene allows instructors to flexibly trial potential interventions to discover the optimal approach for their course settings which should boost student's learning outcomes in long term. [ABSTRACT FROM AUTHOR]

Excavating a tunnel in a deep and saturated ground affects the short- and long-term hydro-mechanical (H-M) response in the ground surrounding the opening. However, the interactions between transient pore pressure behavior and the corresponding deformation and stresses in the ground ahead of and behind the tunnel face are still not well understood. This paper investigates the transient H-M response of excavating a tunnel in a deep and saturated ground using a two-dimensional axisymmetric coupled model in the computer code Fast Lagrangian Analysis of Continua (FLAC). The tunnel was advanced in a stepwise excavation procedure consisting of undrained excavation and drained consolidation until the final tunnel face was reached. The final excavated face was then left to consolidate toward the steady-state condition. The main results of the paper are as follows: (1) when simulating a tunnel excavation in deep saturated ground using the convergence-confinement method, the unloading factors should be nonlinear and should consists of the mechanical unloading factor in the form of excavation force and the hydraulic unloading factor in the form of excavation pore pressure. These two unloading factors are necessary because the induced H-M response near the tunnel face is a rather transient response instead of an initial or final response. Moreover, it is observed that the pore pressure dissipation is not linear either with time or with distance to the tunnel face, (2) a relationship between the unloading factors and the distance to the tunnel face should then be established. This relationship is vital because it will provide the timing for tunnel support installation, and (3) the extrusion and the convergence of the advance core could be related through the proposed equations capturing the linear relationships between the face extrusion and its convergence as well as between the core extrusion and its pre-convergence. Through these relationships, the tunnel engineer may be able to estimate the magnitude of the deformation ahead of the face, which will subsequently allow control of the deformation behind the face. [ABSTRACT FROM AUTHOR]

This paper provides a reply to articles by Nicola Angius and Guiseppe Primiero responding to our paper 'Software Intensive Science' (Symons and Horner, Philosophy and Technology, ). [ABSTRACT FROM AUTHOR]

This article introduces the extended versions of selected papers from the refereed proceedings of the 16th International Conference on Runtime Verification (RV 2016) held in Madrid, Spain, in September 2016. Runtime verification encompasses all aspects of monitoring and analysis of hardware, software, and system executions in general. Runtime verification techniques are lightweight dynamic techniques to assess and enforce correctness, reliability, and robustness during system execution. These techniques are significantly more powerful and versatile than conventional testing, and more practical than exhaustive formal verification (at the price of incomplete coverage). [ABSTRACT FROM AUTHOR]

This paper discusses a simple heuristic to minimize the total tardiness in a single machine scheduling problem. The problem of minimizing total tardiness in single machine scheduling is a combinatorial problem. Hence, heuristic development for such problems is inevitable. In this paper, an attempt has been made to develop a simple heuristic, alternatively called greedy heuristic, to minimize the total tardiness in a single machine scheduling problem with n independent jobs, each having its processing time and due date. Further, its solution accuracy is compared with the optimal solution of a set of randomly generated problems using an ANOVA experiment. From the ANOVA experiment, it is observed that the solution of the simple heuristic proposed in this paper does not differ significantly from the optimal solution at a significance level of 0.05. [ABSTRACT FROM AUTHOR]

To improve the hot-pressing process currently employed in laminated object manufacturing (LOM), an innovative heating-and-pressing separation system is proposed, and heat transfer problems of this system are investigated. A thermal model is first established. It is solved numerically by the finite element method (FEM) software ANSYS, and verified by experiments. Based on the numerical solution under various operating conditions, it is found that the operating temperature of an adhesive can be reached quickly when the heater is maintained at a higher temperature, corresponding to a deeper heat-affected zone. This shortcoming can be effectively reduced if the speed of the heater is increased. Hence, a higher heater temperature together with a higher moving speed is suggested to shorten processing time and promote manufacturing efficiency. Through analysis, the appropriate distance between the roller and the heater, so as to obtain finished parts of high quality, is determined. [ABSTRACT FROM AUTHOR]

Constructing Markov chains with desired statistical properties is of critical importance for many applications in economics and finance. This paper proposes a moment-matching method for generating finite-state Markov chains with flexible distributions, including empirically-relevant processes with non-zero skewness and excess kurtosis. In our method, we preserve the most appealing features of the existing methods, including full analytical tractability and minimal computational cost. The new method derives the key moments of the Markov chain as closed-form functions of its parameters. It thus offers a simple plug-in procedure requiring neither numerical integration nor optimization. Using the method amounts to plugging the targeted values of mean, standard deviation, serial correlation, skewness, and excess kurtosis into a simple procedure. The proposed method outperforms the existing methods over a wide range of the parameter space, especially for leptokurtic processes with characteristic roots close to unity. The supplementary materials include ready-to-use computer codes of the plug-in procedures and practical guidelines. [ABSTRACT FROM AUTHOR]

This special issue collects current advances in the ongoing attempt to obtain synergies from the combination of Tests and Proofs. [ABSTRACT FROM AUTHOR]

Presents an introduction to the August 2004 issue of the "International Journal of Parallel Programming," based on the 17th International Conference on Supercomputing, San Francisco, California, during June 21-26, 2003.

This article introduces papers and studies published in the February 2003 issue of the periodical "International Journal of Parallel Programming,". The publication contains four of the best papers presented in the 2002 International Symposium on High Performance Computing in Japan. Moreover, the highlights of the published papers are also presented together with the necessary recommendations.

Abstract  This paper considers a particular case of linear bilevel programming problems with one leader and multiple followers. In this model, the followers are independent, meaning that the objective function and the set of constraints of each follower only include the leader’s variables and his own variables. We prove that this problem can be reformulated into a linear bilevel problem with one leader and one follower by defining an adequate second level objective function and constraint region. In the second part of the paper we show that the results on the optimality of the linear bilevel problem with multiple independent followers presented in Shi et al. [The kth-best approach for linear bilevel multi-follower programming, J. Global Optim. 33, 563–578 (2005)] are based on a misconstruction of the inducible region. [ABSTRACT FROM AUTHOR]

Business Process flexibility supports organizations in changing their everyday work activities to remain competitive. Since much research has been done on this topic a better awareness on the current state of knowledge is needed. This paper reports the results of a systematic literature review to develop a map on Business Process flexibility with a special focus on software systems related aspects. It covers a spectrum of the state of the art from academic point of view. It includes 164 research works from the main computer science digital libraries. After an introduction into the topic the applied methodology is described. The output of the paper is in the form of schemes and reflections. Starting from the needs for Business Process flexibility, its impact on Business Process life-cycle is introduced. Successively instruments used to express and to support Business Process flexibility are presented together with related validation scenarios. In this paper we also highlight possible future research lines needing further investigations. In particular we identified room for future works in the area of languages for modeling flexibility, on-the-fly verification solutions, adaptation of Business Process running instances, and techniques for evolution recognition. [ABSTRACT FROM AUTHOR]

The NC program interpreter plays an important role in CNC systems. It checks for errors and translates NC programs into commands that can be executed by the CNC control module. NC program specifications differ a lot among different CNC manufacturers. However, the existing NC program interpreters only support one specific program format, which increases the programming difficulty and enterprise cost. Meanwhile, due to the closed interpreter structure, it is difficult to develop and implement new CNC function instructions, which limits the openness of CNC systems. In order to solve these problems, this paper presented a novel analysis of NC language's grammar, and designed a set of hierarchical and modular Extend Backus-Naur Form (EBNF) expressions to describe NC language. An extensible interpreter based on EBNF was proposed. Through interaction with users to add new instructions, the system can utilize lexical analyzer (Lex) and yet another compiler compiler (Yacc) to generate a new matching interpreter. This method can also help users to produce a matching interpreter for a specific NC program specification. A prototype interpreter was developed successfully, the validity of which was verified by tests. [ABSTRACT FROM AUTHOR]

As the first time, this paper attempts to recreate the discharge coefficient (DC) of side slots by another artificial intelligence procedure named "Outlier Robust Extreme Learning Machine (ORELM)". Accordingly, at first, the variables affecting the DC comprising the ratios of the flow depth to the side slot length (Ym/L), the side slot crest elevation to the side slot length (W/L), the main channel width to the side slot length (B/L), as well as the Froude number (Fr) are determined and subsequently five ORELM models (ORELM 1 to ORELM 5) are created utilizing these variables. From that point forward, laboratory measurements are arranged into two datasets comprising training (70%) and testing (30%). At the subsequent stage, the best model alongside the most affecting input variables is presented by executing a sensitivity examination. The most impressive model (i.e., ORELM 3) reproduces DC values as far as B/L, W/L and Fr. It is worth focusing on that ORELM 3 forecasts DC values with worthy precision. For instance, the correlation coefficient (R), the scatter index (SI) and the Nash–Sutcliffe effectiveness (NSC) for ORELM 3 are acquired in the examination state to be 0.936, 0.049 and 0.852, independently. Examining the outcomes yielded from the simulation demonstrates that W/L and Fr are the most impacting factors to reproduce the DC. Besides, the findings of the sensitivity examination uncover that ORELM 3 acts in an underestimated way. Finally, a computer code is put forward to compute the DC of side slots. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including research in information filtering and integration, the problem of automated extraction of target content from a webpage, and impact of Aspect Oriented Programming (AOP) on software.

The article discusses various reports published within the issue, including one by Markus Nordén and colleagues on the performance of the parallel partial differential equation solver written in Open Multi-Processing (OpenMP) and another by Alejandro Duran and colleagues on the important lack in the current OpenMP language specification.

Busy periods of finite buffer tandem service systems have not been addressed in the available literature. This paper defines the stage-I and stage-II busy periods of a two-stage tandem service system Mx/M/c→/PH(r)/1/K, analytically obtains their distributions, and presents efficient algorithms for the distributions with uniform error in time. The detailed analysis and algorithmic implementation for the two-stage tandem service system are completed, and the theoretical basis for its potential practical applications is provided. [ABSTRACT FROM AUTHOR]

The development of Extract-Transform-Load (ETL) processes is the most complex, time-consuming and expensive phase of data warehouse development. Yet, the dynamics of modern business systems demand a more agile and flexible approach to their development. As a result, current research in this area is focused on ETL process conceptualization and the automation of ETL process development. This paper proposes a novel solution for automating ETL processes using the domain-specific modeling (DSM) approach. The proposed solution is based on the formal specification of ETL processes and the implementation of such formal specifications. Thus, in accordance with the DSM approach, several new domain-specific languages (DSLs) are introduced, each defining concepts relevant for a specific aspect of an ETL process. The focus of this paper is the actual implementation of the formal specification of an ETL process. To this end, a specific ETL platform (ETL-PL) is introduced to technologically support both the modeling of ETL processes (i.e., the creation of models in accordance with the introduced DSLs) and the automated transformation of the created models into the executable code of a specific application framework (representing ETL-PL's execution environment). It should be emphasized that ETL-PL actually presumes the dynamic execution of ETL models or, more precisely, the executable code is generated at runtime. Thus the execution environment consists of code generator components and the components implementing the application framework. ETL-PL has been implemented as an extension of the .NET platform. [ABSTRACT FROM AUTHOR]

Aiming at efficient similarity search, hash functions are designed to embed high-dimensional feature descriptors to low-dimensional binary codes such that similar descriptors will lead to binary codes with a short distance in the Hamming space. It is critical to effectively maintain the intrinsic structure and preserve the original information of data in a hashing algorithm. In this paper, we propose a novel hashing algorithm called Latent Structure Preserving Hashing (LSPH), with the target of finding a well-structured low-dimensional data representation from the original high-dimensional data through a novel objective function based on Nonnegative Matrix Factorization (NMF) with their corresponding Kullback-Leibler divergence of data distribution as the regularization term. Via exploiting the joint probabilistic distribution of data, LSPH can automatically learn the latent information and successfully preserve the structure of high-dimensional data. To further achieve robust performance with complex and nonlinear data, in this paper, we also contribute a more generalized multi-layer LSPH (ML-LSPH) framework, in which hierarchical representations can be effectively learned by a multiplicative up-propagation algorithm. Once obtaining the latent representations, the hash functions can be easily acquired through multi-variable logistic regression. Experimental results on three large-scale retrieval datasets, i.e., SIFT 1M, GIST 1M and 500 K TinyImage, show that ML-LSPH can achieve better performance than the single-layer LSPH and both of them outperform existing hashing techniques on large-scale data. [ABSTRACT FROM AUTHOR]

In this paper, we present an efficient implementation of heuristic procedures for solving the continuous network design problem where network users behave according to Wardrop's first principle of traffic equilibrium. Numerical results involving a ‘standard’ benchmark problem are given. Also, it is shown that the cost mapping arising in the Iterative-Optimization-Assignment algorithm is integrable if and only if the volume-delay function is of either the BPR or some logarithmic form. [ABSTRACT FROM AUTHOR]

The travelling salesman problem (TSP) is a well-known NP-hard problem. It is difficult to efficiently find the solution of TSP even with the large number of gene instances. Evolutionary approaches such as genetic algorithm have been widely applied to explore the huge search space of TSP. However, the feasibility constraints of TSP make it difficult to devise an effective crossover method. In this paper, we propose an improved constructive crossover for TSP. As the performance of graphics processing units (GPUs) rapidly improves, GPU-based acceleration is increasingly required for complex computation problems. Unfortunately, the constructive crossover methods cannot be easily implemented in a parallel fashion because each gene element of offspring is dependent on the previous element in the gene string. In this paper, we propose a more effective method with which large number of genes can evolve effectively by exploiting the parallel computing power of GPUs and an effective parallel approach to genetic TSP where crossover methods cannot be easily implemented in parallel fashion. [ABSTRACT FROM AUTHOR]

Models of natural supersymmetry give rise to a weak scale m weak ∼ m W , Z , h ∼ 100 GeV without any (implausible) finetuning of independent contributions to the weak scale. These models, which exhibit radiatively driven naturalness (RNS), are expected to arise from statistical analysis of the string landscape wherein large soft terms are favored, but subject to a not-too-large value of the derived weak scale in each pocket universe of the greater multiverse. The string landscape picture then predicts, using the Isajet SUSY spectra generator Isasugra, a statistical peak at m h ∼ 125 GeV with sparticles generally beyond current LHC search limits. In this paper, we investigate how well these conclusions hold up using other popular spectra generators: SOFTSUSY, SPHENO and SUSPECT (SSS). We built a computer code DEW4SLHA which operates on SUSY Les Houches Accord files to calculate the associated electroweak naturalness measure Δ EW . The SSS generators tend to yield a Higgs mass peak ∼ 125 –127 GeV with a superparticle mass spectra rather similar to that generated by Isasugra. In an Appendix, we include loop corrections to Δ EW in a more standard notation. [ABSTRACT FROM AUTHOR]

The recent boom in mobile device usage has provided more opportunities, competition and also increased complexities for content providers to monetize their information goods. Although mobile devices are becoming increasingly powerful, their hardware, software and connectivity are relatively more limited compared to desktop and enterprise systems. As a result, various content optimization services have emerged. This paper focuses on content optimization services that modify and reorganize content to reduce the size of content and enhance the performance of processing on the content. For most content providers, this optimization process needs to be fast, scalable and yet aligned with their monetization strategies and cost requirements. Based on our experience on content optimization services, this paper presents the economics related to these services. In particular, we present some practical considerations when these services are implemented on a cloud, which is typically perceived to be a cheaper and more scalable option compared to traditional dedicated servers. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the effects of higher moments on multi-period portfolio selection with fuzzy returns. This paper gives the definitions of possibilistic mean and variance about the product of multiple fuzzy numbers. Based on these definitions, three multi-period fuzzy portfolio optimization models are proposed. The proposed models aim to maximize terminal wealth and minimize terminal risk by taking into account some realistic constraints including higher moments, budget constraint, round-lot constraint, cardinality constraint and bound constraint. To ensure the selection of the best solutions, a novel fuzzy programming approach-based self-adaptive differential evolution algorithm is designed to solve the proposed models. A numerical example is given to demonstrate the application of the proposed models. Computational results show that the designed algorithm is effective for solving complex portfolio selection model with realistic constraints. [ABSTRACT FROM AUTHOR]

This paper describes the $${{\tt StatWeave}}$$ system for making reproducible statistical analyses. $${{\tt StatWeave}}$$ differs from other systems for reproducible analysis in several ways. The two main differences are: (1) Several statistics programs can be in used in the same document. (2) Documents can be prepared using OpenOffice or $${\hbox{\LaTeX}}$$. The main part of this paper is an example showing how to use $${{\tt R}}$$ and $${{\tt SAS}}$$ together in an OpenOffice text document. The paper also contains some practical considerations on the use of literate programming in statistics. [ABSTRACT FROM AUTHOR]

The present paper proposes a novel algorithm for recognition of handwritten digits. For this, the present paper classified the digits into two groups: one group consists of blobs with/without stems and the other digits with stems only. The blobs are identified based on a new concept called morphological region filling methods. This eliminates the problem of finding the size of blobs and their structuring elements. The digits with blobs and stems are identified by a new concept called 'connected component'. This method completely eliminates the complex process of recognition of horizontal or vertical lines and the property called 'concavities'. The digits with only stems are recognized, by extending stems into blobs by using connected component approach of morphology. The present method has been applied and tested with various handwritten digits from modified NIST (National Institute of Standards and Technology) handwritten digit database (MNIST), and the success rate has been given. The present method is also compared with various existing methods. [ABSTRACT FROM AUTHOR]

In this paper we present a novel approach for the specification of user rights in the context of an object oriented use case driven development process. Basically, we extend the specification of methods by a permission section describing the right of some actor to call the method of an object. Our approach is both role based and context based while allowing for permissions to be specified at a fine-grained data-dependent level. We use first-order logic with a built-in notion of objects and classes (provided with an algebraic semantics) as our syntactic and semantic framework. In the second part of the paper, we demonstrate the application of this approach in a model-based context to generate permissions in distributed peer-to-peer networks. [ABSTRACT FROM AUTHOR]

To save time, developers often search for code examples that implement their desired software features. Existing code search techniques typically focus on finding code snippets for a single given query, which means that developers need to perform a separate search for each desired functionality. In this paper, we propose FACER (F eature-driven A PI usage-based C ode E xamples R ecommender), a technique that avoids repeated searches through opportunistic reuse. Specifically, given the selected code snippet that matches the initial search query, FACER finds and suggests related code snippets that represent features that the developer may want to implement next. FACER first constructs a code fact repository by parsing the source code of open-source Java projects to obtain methods' textual information, call graphs, and Application Programming Interface (API) usages. It then detects unique features by clustering methods based on similar API usages, where each cluster represents a feature or functionality. Finally, it detects frequently co-occurring features across projects using frequent pattern mining and recommends related methods from the mined patterns. To evaluate FACER, we run it on 120 Java Android apps from GitHub. We first manually validate that the detected method clusters represent methods with similar functionality. We then perform an automated evaluation to determine the best parameters (e.g., similarity threshold) for FACER. We recruit 10 professional developers along with 39 experienced students to judge FACER's recommendation of related methods. Our results show that, on average, FACER's recommendations are 80% precise. We also survey a total of 20 professional Android and Java developers to understand their code search and reuse experiences, and also to obtain their feedback on the usability and usefulness of FACER. The survey results show that 95% of our surveyed professional developers find the idea of related method recommendations useful during code reuse. [ABSTRACT FROM AUTHOR]

This paper presents an external parallelization of Constraint Programming (CP) search tree mixing both static and dynamic partitioning. The principle of the parallelization is to partition the CP search tree into a set of sub-trees, then assign each sub-tree to one computing core in order to perform a local search using a sequential CP solver. In this context, static partitioning consists of decomposing the CP variables domains in order to split the CP search tree into a set of disjoint sub-trees to assign them to the cores. This strategy performs well without adding an extra cost to the parallel search, but the problem is the load imbalance between computing cores. On the other hand, dynamic partitioning is based on preservation of the search state to generate, dynamically or on demand, the sub-trees that are assigned to the cores. This strategy offers good load balancing between the different computing cores, but computing overcosts appear due to the initialisation of the search when a sub-tree is migrated from one core to another. In this paper, we propose a new partitioning strategy that mixes the static and dynamic partitioning and enjoys the benefits of each strategy. This mixed partitioning is designed to run on shared and distributed memory architectures. The performances obtained are illustrated by solving the CP problems modelled using the FlatZinc format and solved using the Google OR-Tools solver on top of the parallel Bobpp framework. [ABSTRACT FROM AUTHOR]

Given a massive set of records, similarity join is to find pairs of records with similarity score greater than a threshold. In this paper, we address the problem of scaling up similarity join for general metric distance functions using MapReduce. First, we propose a novel index structure, Similarity Join Tree (SJT), which partitions data based on the underlying data distribution, and distributes similar records to the same group. Different from existing approaches, SJT can prune a large number of comparisons within reduce tasks by utilizing the by-product results generated in partitioning data. Then, to avoid the straggler reduce tasks, we design a graph partition algorithm by extending the well known Fiduccia-Mattheyses algorithm which can ensure load balancing while minimizing communication cost and redundancy in all reduce tasks. Experimental results using real data sets show that our approach is more effective and scalable compared to state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

Optimization of oil-imports portfolio has attracted considerable attention from corporate operators as well as government and its strategic planners. This paper proposes a methodology of oil-importing portfolio optimization based on the fundamental process of intelligent knowledge management (IKM). Centering on the maritime system, optimal solutions are derived for different risk scenarios. Specifically, three main steps are involved: formulating a multi-objective programming (MOP) model, integrating the composite risk exposure with domain knowledge, as well as knowledge acquisition on risk scenarios and influence of transportation risk. For illustration, optimization of the maritime structure of China's oil imports is performed to verify the practicability of the novel methodology. Experimental results suggest that the risk-adjusted factors' augmentation can spread the risk wider and eventually enhance risk optimization capability in the MOP model. With a given risk-adjusted factor, the influence of transportation risk on an optimal plan is simulated and analyzed. The paper uses the fundamental IKM process for transforming the data (rough knowledge) into intelligent knowledge (transformation from T1 to T2) in the empirical study on risk integration and optimization of oil-importing maritime system. It is helpful to explore hidden patterns. What's more, results suggest that it is necessary to highlight the influence of transportation risk in order to support decision makers from different domains to obtain more reasonable optimal solutions. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of synchronization algorithms on ccNUMA multiprocessors, from the perspectives of the architecture and the operating system. In contrast with previous related studies that emphasized the relative performance of synchronization algorithms, this paper takes a new approach by analyzing the sources of synchronization latency on ccNUMA architectures and how can this latency be reduced by leveraging hardware and software schemes in both dedicated and multiprogrammed execution environments. From the architectural perspective, the paper identifies the implications of directory-based cache coherence on the latency and scalability of synchronization instructions and examines if and how can simple hardware that accelerates these instructions be leveraged to reduce synchronization latency. From the operating system's perspective, the paper evaluates in a unified framework, user-level, kernel-level and hybrid algorithms for implementing scalable synchronization in multiprogrammed execution environments. Along with visiting the aforementioned issues, the paper contributes a new methodology for implementing fast synchronization algorithms on ccNUMA multiprocessors. The relevant experiments are conducted on the SGI Origin2000, a popular commercial ccNUMA multiprocessor. [ABSTRACT FROM AUTHOR]

Overlapping communication with computation is a well-known approach to improving performance. Previous research has focused on optimizations performed by the programmer. This paper presents a compiler algorithm that automatically determines the appropriate loop indices of a given nested loop and applies loop interchange and tiling in order to overlap communication with computation. The algorithm avoids generating redundant communication by providing a framework for combining information on data dependence, communication, and reuse. It also describes a method of generating messages to exchange data between processors for tiled loops on distributed memory machines. The algorithm has been implemented in our High Performance Fortran (HPF) compiler, and experimental results have shown its effectiveness on distributed memory machines, such as the RISC System/6000 Scalable POWERparallel System. This paper also discusses the architectural problems of efficient optimization. [ABSTRACT FROM AUTHOR]

Big Data refers to the massive amounts of structured and unstructured data being produced every day from a wide range of sources. Big Data is difficult to work with and needs a large number of machines to process it, as well as software capable of running in a distributed environment. MapReduce is a recent programming model that simplifies writing distributed programs on distributed systems. For MapReduce to work it needs to divide work amongst computers in a network. Consequently, the performance of MapReduce is dependent on how evenly it distributes the workload. This paper proposes an adaptive sampling mechanism for total order partitioning that can reduce memory consumption whilst partitioning with a trie-based sampling mechanism (ATrie). The performance of the proposed algorithm is compared to a state of the art trie-based partitioning system (ETrie). Experiments show the proposed mechanism is more adaptive and more memory efficient than previous implementations. Since ATrie is adaptive, its performance depended on the type of data used. A performance evaluation of a 2-level ATrie shows it uses 2.43 times less memory for case insensitive email addresses, and uses 1,024 times less memory for birthdates compared to that of a 2-level ETrie. These results show the potential of the proposed method. [ABSTRACT FROM AUTHOR]