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摘要:Auctions are important market mechanisms for the allocation of goods and services. Combinatorial auctions are those auctions in which buyers can place bids on combinations of items. Combinatorial auctions have many applications. The paper presents the CRAB software system. CRAB is a non-commercial software system for generating, solving, and testing of combinatorial auction problems. The system solves problems by Balas' method or by the primal-dual algo-rithm. CRAB is implemented in Ruby and it is distributed as the file crab.rb. The system is freely available on web pag-es for all interested users...
摘要:Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is named Χ(Chi)-Pro Milestone and supports four types of questions, namely: Multiple-choice, True/False, Short-Answer and Free-Response Essay questions. The study is motivated by the fact that student number in schools and universities is continuously growing at high, non-linear, and uncontrolled rates. This growth, however, is not accompanied by an equivalent growth of educational resources (mainly: instructors, classrooms, and labs). A direct result of this situation is having relatively large number of students in each classroom. It is observed that providing and using online-examining systems could be intractable and expensive. As an alternative, paper-based exams can be used. One main issue is that manually produced paper-based exams are of low quality because of some human factors such as instability and relatively narrow range of topics [1]. Further, it is observed that instructors usually need to spend a lot of time and energy in composing paper-based exams with multiple forms. Therefore, the use of computers for automatic production of paper-based exams from question banks is becoming more and more important. Methodology: The design and evaluation of X-Pro Milestone are done by considering a basic set of design principles that are based on a list of identified Functional and Non-Functional Requirements. Deriving those requirements is made possible by developing X-Pro Milestone using the Iterative and Incremental model from software engineering domain. Results: We demonstrate that X-Pro Milestone has a number of excellent characteristics compared to the exam-preparation and question banks tools available in market. Some of these characteristics are: ease of use and operation, user-friendly interface and good usability, high security and protection of the question bank-items, high stability, and reliability. Further, X-Pro Milestone makes initiating, maintaining and archiving Question-Banks and produced exams possible. Putting X-Pro Milestone into real use has showed that X-Pro Milestone is easy to be learned and effectively used. We demonstrate that X-Pro Milestone is a cost-effective alternative to online examining systems with more and richer features and with low infrastructure requirements....
摘要: class="MsoNormal" style="text-align:justify;"> lang="EN-US" style="font-size:12px;font-family:Verdana;">The larger the size of the data, structured or unstructured, the harder to understand and make use of it. One of the fundamentals to machine learning is feature selection. Feature selection, by reducing the number of irrelevant/redundant features, dramatically reduces the run time of a learning algorithm and leads to a more general concept. In this paper, realization of feature selection through a neural network based algorithm, with the aid of a topology optimizer genetic algorithm, is investigated. We have utilized NeuroEvolution of Augmenting Topologies (NEAT) to select a subset of features with the most relevant connection to the target concept. Discovery and improvement of solutions are two main goals of machine learning, however, the accuracy of these varies depends on dimensions of problem space. Although feature selection methods can help to improve this accuracy, complexity of problem can also affect their performance. Artificialneural networks are proven effective in feature elimination, but as a consequence of fixed topology of most neural networks, it loses accuracy when the number of local minimas is considerable in the problem. To minimize this drawback, topology of neural network should be flexible and it should be able to avoid local minimas especially when a feature is removed. In this work, the power of feature selection through NEAT method is demonstrated. When compared to the evolution of networks with fixed structure, NEAT discovers significantly more sophisticated strategies. The results show NEAT can provide better accuracy compared to conventional Multi-Layer Perceptron and leads to improved feature selection.

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摘要:Software reliability for business applications is becoming a topic of interest in the IT community. An effective method to validate and understand defect behaviour in a software application is Fault Injection. Fault injection involves the deliberate insertion of faults or errors into software in order to determine its response and to study its behaviour. Fault Injection Modeling has demonstrated to be an effective method for study and analysis of defect response, validating fault-tolerant systems, and understanding systems behaviour in the presence of injected faults. The objectives of this study are to measure and analyze defect leakage; Amplification Index (AI) of errors and examine “Domino” effect of defects leaked into subsequent Software Development Life Cycle phases in a business application. The approach endeavour to demonstrate the phasewise impact of leaked defects, through causal analysis and quantitative analysis of defects leakage and amplification index patterns in system built using technology variants (C#, VB 6.0, Java)....
摘要:We construct a complete-connective regular network based on Self-replication Space and the structural principles of cantor set and Koch curve. A new definition of dimension is proposed in the paper, and we also investigate a simplified method to calculate the dimension of two regular networks. By the study results, we can get a extension: the formation of Euclidean space may be built by the process of the Big Bang's continuously growing at a constant rate of three times....
摘要: class="MsoNormal"> lang="EN-GB">Automation in measurement has wide range of electrical metrology applications and construction of powerful calibration software is one of the highly accurate metrological laboratories' priorities. Thus, two automatic systems for controlling and calibrating the electrical reference standards have been established at National Institute for Standards (NIS), w:st="on"> w:st="on">Egypt. The first system has been built to calibrate the zener diode reference standards while the second one has been built to calibrate the electrical sourcing and measuring instruments. These two systems act as the comprehensive and reliable structure that, from the national electrical standards, disseminates the traceability to all the electrical units under calibration. The software of the two systems has been built using the Laboratory Virtual Instrument Engineering Workbench (LabVIEW) graphical language. lang="EN-US">The standard development procedures have been followed in the building of both systems software. The software requirement specifications as well as functional specifications are taken into consideration. lang="EN-GB"> Design, implementation and testing of the software have been performed. Furthermore, software validation for measurements' uncertainty as well as results' compatibility in both automatic and manual modes has been achieved. lang="EN-US">

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摘要:Many numerical methods reduce the solving of a complicated problem to a set of elementary problems. In this way, the author reduced the finding of solution boxes of a system of inequalities, the computation of integral values with error bounds, the approximation of global maxima to computing solution boxes of one inequality. These previous papers presented the mathematical aspects of the problems first of all. In this paper the computational handling of solution boxes of an inequality (as a new tool of computer methods) is discussed in detail....
摘要:Journals and their citation relations are abstracted into journal citation networks, basing on CSTPC journal database from year 2003 to 2006. The network shows some typical characteristics from complex networks. This paper presents the idea of using motifs, subgraphs with higher occurrence in real network than in random ones, to discover two different citation patterns in journal communities. And a further investigation is addressed on both motif granularity and node centrality to figure out some reasons on the differences between two kinds of communities in journal citation network....
摘要:Network RTK (Real-Time Kinematic) is a technology that is based on GPS (Global Positioning System) or more gener-ally on GNSS (Global Navigation Satellite System) measurements to achieve centimeter-level accuracy positioning in real-time. Reference station placement is an important problem in the design and deployment of network RTK systems as it directly affects the quality of the positioning service and the cost of the network RTK systems. This paper identifies a new reference station placement for network RTK, namely QoS-aware regional network RTK reference station placement problem, and proposes an algorithm for the new reference station placement problem. The algorithm can always produce a reference station placement solution that completely covers the region of network RTK....
摘要:

style="font-size:12px;font-family:Verdana;">The work of software engineers is inherently cognitive. Integral to their duties is understanding and developing several artifacts. Each one is based on a specific model and a given level of abstraction. What distinguishes Software Engineering is the logical complexity of some artifacts (especially programs), the high dependency among them, and the fact that the success of the software project also depends on the human and social factors, which characterize the engineers as individuals and as a group. The complexity of the daily tasks within a software development team motivates the investigation on the relevance of automating the software professionals' cognitive processes in order to make their work easier and more efficient. The success of this endeavor is expected to emerge as Cognitive Software Engineering. For this aim, the present article suggests a research framework and roadmap, which build on the current state of the art. Some future directions in the Cognitive Software Engineering are presented.

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摘要: class="MsoNormal" style="text-align:justify;"> lang="EN-US" style="font-size:12px;font-family:Verdana;">Cleaning duplicate data is a major problem that persists even though many works have been done to solve it, due to the exponential growth of data amount treated and the necessity to use scalable and speed algorithms. This problem depends on the type and quality of data, and differs according to the volume of data set manipulated. In this paper we are going to introduce a novel framework based on extended fuzzy C-means algorithm by using topic ontology. This work aims to improve the OLAP querying process over heterogeneous data warehouses that contain big data sets, by improving query results integration, eliminating redundancies by using the extended classification algorithm, and measuring the loss of information.

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摘要:Segmentation of moving objects efficiently from video sequence is very important for many applications. Background subtraction is a common method typically used to segment moving objects in image sequences taken from a statistic camera. Some existing algorithms cannot adapt to changing circumstances and require manual calibration in terms of specification of parameters or some hypotheses for changing background. An adaptive motion segmentation method is developed according to motion variation and chromatic characteristics, which prevents undesired corruption of the background model and does not consider the adaptation coefficient. RGB color space is selected instead of introducing complex color models to segment moving objects and suppress shadows. A color ratio for 4-connected neighbors of a pixel and multi-scale wavelet transformation are combined to suppress shadows. The mentioned approach is scene-independent and high correct segmentation. It has been shown that the approach is robust and efficient to detect moving objects by experiments....
摘要:In software engineering, software measures are often proposed without precise identification of the measurable concepts they attempt to quantify: consequently, the numbers obtained are challenging to reproduce in different measurement contexts and to interpret, either as base measures or in combination as derived measures. The lack of consistency when using base measures in data collection can affect both data preparation and data analysis. This paper analyzes the similarities and differences across three different views of measurement methods (ISO International Vocabulary on Metrology, ISO 15939, and ISO 25021), and uses a process proposed for the design of software measurement methods to analyze two examples of such methods selected from the literature....
摘要:The trust plays an extremely important role in online shopping. In order to make online shopping trusty, this paper puts foreword a new trust model in e-commerce environment GIR-TM (Groups' Internal Recommendation Trust Model). First, it regarded the network as a combination of groups, and then did the internal recommendation based on these groups. The GIR-TM, in the process of recommendation, distinguished clearly between the trust degrees of recommen-dation node and the trust degrees of recommended node, and then calculated the integrated credibility value of the recommended node according to the weight of recommendation node in the group, the partial trust degree and the de-gree of recommendation when the recommendation node recommends the recommended node, and the overall credibil-ity value of recommended node as well. Lastly through listing the experimental data and comparing with the HHRB-TM (History and Honest Recommendation Based Trust Model) on the same condition, it is verified that GIR-TM is feasible and effective....
摘要: class="MsoNormal" style="text-align:justify;"> style="font-size:10pt;font-family:'}', serif;" lang="EN-US"> style="font-size:12px;font-family:Verdana;">Formal methods can be used at any stage of product development process to improve the software quality and efficiency using mathematical models for analysis and verification. From last decade, researchers and practitioners are trying to establish successful transfer of practices of formal methods into industrial process development. In the last couple of years, numerous analysis approaches and formal methods have been applied in different settings to improve software quality. In today's highly competitive software development industry, companies are striving to deliver fast with low cost and improve quality solutions and agile methodologies have proved their efficiency in acquiring these. Here, we will present an integration of formal methods, specifications and verification practices in the most renowned process development methodology of agile class="apple-converted-space" style="font-size:12px;font-family:Verdana;"> style="font-size:12px;font-family:Verdana;">i.e. class="apple-converted-space" style="font-size:12px;font-family:Verdana;"> style="font-size:12px;font-family:Verdana;">extreme programming with a conceptual solution. That leads towards the development of a complete formalized XP process in future. This will help the practitioners to understand the effectiveness of formal methods using in agile methods that can be helpful in utilizing the benefits of formal methods in industry.

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摘要:Word stemming is one of the most important factors that affect the performance of many natural language processing applications such as part of speech tagging, syntactic parsing, machine translation system and information retrieval systems. Computational stemming is an urgent problem for Arabic Natural Language Processing, because Arabic is a highly inflected language. The existing stemmers have ignored the handling of multi-word expressions and identification of Arabic names. We used the enhanced stemming for extracting the stem of Arabic words that is based on light stemming and dictionary-based stemming approach. The enhanced stemmer includes the handling of multiword expressions and the named entity recognition. We have used Arabic corpus that consists of ten documents in order to evaluate the enhanced stemmer. We reported the accuracy values for the enhanced stemmer, light stemmer, and dictionary-based stemmer in each document. The results obtain shows that the average of accuracy in enhanced stemmer on the corpus is 96.29%. The experimental results showed that the enhanced stemmer is better than the light stemmer and dictionary-based stemmer that achieved highest accuracy values....
摘要:Frameworks are developed to capture the recurring design practices in terms of skeletons of software subsystems/ systems. They are designed ‘abstract' and ‘incomplete' and are designed with predefined points of variability, known as hot spots, to be customized later at the time of framework reuse. Frameworks are reusable entities thus demand stricter and rigorous testing in comparison to one-time use application. It would be advisable to guaranty the production of high quality frameworks without incurring heavy costs for their rigorous testing. The overall cost of framework development may be reduced by designing frameworks with high testability. This paper aims at discussing various metric models for testability analysis of frameworks in an attempt to having quantitative data on testability to be used to plan and monitor framework testing activities so that the framework testing effort and hence the overall framework development effort may be brought down. The models considered herein particularly consider that frameworks are inherently abstract and variable in nature....
摘要:This article presents a new signcryption scheme which is based on the Schnorr digital signature algorithm. The new scheme represents my personal contribution to signcryption area. I have implemented the algorithm in a program and here are provided the steps of the algorithm, the results and some examples. The paper also contains the presentation of the original Signcryption scheme, based on ElGamal digital signature and discusses the practical applications of Signcryption in real life. The purpose of the study is to combine the public key encryption with Schnorr digital signature in order to obtain less computational and communicational costs. Signcryption primitive is a better approach then Encrypt-then-Sign or Sign-then-Encrypt methods regarding the costs. All these algorithms offer the possibility to transmit a message over an insecure channel providing both authenticity and confidentiality....
摘要:

A low energy consumption clustering algorism based on LEACH is researched. Firstly, A method for obtaining the number of clusters k is given, then using the K-Means algorism to divide all the sensor nodes in WSN to the k clusters, in the whole network life cycle the cluster will not changed, and when the energy of cluster head is lower than some threshold, it will be changed. The data transmission between cluster heads to sink node use mixed model, namely, the cluster near the sink node using the single hop and the one far from it using the multiple hops. The experiment shows our method has the longer life cycle and more received information. It is an effective clustering protocol.

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摘要:In this Paper, a classification method based on neural networks is presented for recognition of 3D objects. Indeed, the objective of this paper is to classify an object query against objects in a database, which leads to recognition of the former. 3D objects of this database are transformations of other objects by one element of the overall transformation. The set of transformations considered in this work is the general affine group....
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