327,569 research outputs found

    Developing numerical libraries in Java

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    The rapid and widespread adoption of Java has created a demand for reliable and reusable mathematical software components to support the growing number of compute-intensive applications now under development, particularly in science and engineering. In this paper we address practical issues of the Java language and environment which have an effect on numerical library design and development. Benchmarks which illustrate the current levels of performance of key numerical kernels on a variety of Java platforms are presented. Finally, a strategy for the development of a fundamental numerical toolkit for Java is proposed and its current status is described.Comment: 11 pages. Revised version of paper presented to the 1998 ACM Conference on Java for High Performance Network Computing. To appear in Concurrency: Practice and Experienc

    Software network analyzer for computer network performance measurement planning over heterogeneous services in higher educational institutes

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    In 21st century, convergences of technologies and services in heterogeneous environment have contributed multi-traffic. This scenario will affect computer network on learning system in higher educational Institutes. Implementation of various services can produce different types of content and quality. Higher educational institutes should have a good computer network infrastructure to support usage of various services. The ability of computer network should consist of i) higher bandwidth; ii) proper network design; and iii) higher performance of communication devices/servers. Thus, presently there is no software to plan and help network administrator in determine ability of network services during introduce a new service. Current approach using by network administrators are planning computer network performance via prediction and measure ability of real network performance using hardware/software network analyzer. This approach can influence several problems such as prediction without software always inaccurate and most of the software/hardware network analyzer in real network is limited by network interfaces. Therefore, to encounter these problems, network administrators need software that can plan and measure additional network resources. Thus, this study presents a novel approach for measurement and planning network performance management in heterogeneous environment. The main objectives of this research is to i) identify which approach and problem occurs in Malaysia higher educational institutes; ii) create simulation model that able to plan and measure network performance for various services; iii) software network analyzer development based on simulation model design; and iv) conduct an evaluation of simulation model and software development with real network. These objectives can achieve as follows: i) conduct a survey; ii) select appropriate mathematical formula to create simulation model; iii) select appropriate modeling application for software development; and iv) conduct verification and validation technique for simulation modeling and evaluation of software network analyzer . The results from survey show that most of the network administrators are using hardware/software network analyzer to measure network performance during operational phase. The minimum size of bandwidth capacity has contributed higher network utilization usage. It can generate network congestion and network service failure in higher educational institutes. We create suitable models to evaluate the network performance using Little Law and Queuing theory that can represent similar to hardware/software network analyzer. In order to get accuracy results on the performance of simulation model, we measure (verify and validate) data from lab experiment and real network environment. Development of software network analyzer is based on simulation model architecture. This software will undergo evaluation process using qualitative technique. As a result, this software prototyping can provide a good approximation of real functionality observed in the real network environment. In addition the software is capable of approximating the performance within a minimum error rate. This software network analyzer can significantly enhance to analyze and propose solution on computer network performance. Future work is to develop software network analyzer for planning, suggestion and analyzing computer network performance on wireless transmission (WLAN, WWAN and WiMax) and Ipv6 protocol. We investigate how preparation and planning phases can be applied to heterogeneous environment in order to better utilize network resources. Our software network analyzer prototyping development is based on Fluke Optiview Network Analyzer. Before we develop any software prototype, it should define the following criteria: i) establish prototype objectives; ii) define prototype functionality; iii) develop prototype; and iv) evaluate prototype. Software network analyzer prototype consists of two phases: analyzing computer network performance under optimum condition and without optimum condition. Software network analyzer prototype was developed to measure and predict network activities based on offline condition. We use qualitative technique to measure our software network analyzer prototype to identify this software is able to plan, propose and analyze computer network performance. Evaluation of software network analyzer prototype is based on focus groups in University of Kuala Lumpur (UniKL). Six evaluators are experienced in education and industrial sector will select to complete the survey and interview task. Three evaluators will select who are experienced in industrial sector only, while, another three evaluators experienced in academic and industrial sector. All evaluators have experienced more than 6 to 13 years in network management field. All evaluators need to complete the following task such as: acceptance test, performance test, loading test, network responsive test and repetition test. A common strategy is to design, test, evaluate and then modify the design based on analysis of the prototype.Facultad de Informátic

    Прогнозування дохідності цінних паперів на підґрунті застосування інструментарію нейронних мереж

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    У статті розглянуто можливості використання нейронних мереж для прогнозування дохідності цінних паперів. Побудовано нейронну мережу в програмному середовищі MATLAB, описано процес її розроблення, а також математичні моделі та методи, що використовуються під час її навчання. (Possibilities of the neural networks’ use for the securities’ profit forecasting are considered in the article. In the MATLAB software environment a neural network is built, its development process and also the mathematical models and methods which are used for its training are described.

    Traffic control designing using model predictive control in a high congestion traffic area

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    The paper investigates a designing method for urban traffic management system. A busy traffic area was chosen for test field in the 10^th district of Budapest. The control algorithm is based on model predictive control (MPC). The control aim is to relieve traffic congestion, reduce travel time and improve homogenous traffic flow. Theory and realization details of the control method are also presented. The MPC based control strategy was implemented into the test network´s management system. The applied environment contains microscopic traffic simulator, scientific mathematical software and some computational applications for the evaluation. The simulation results show that the system is able to ameliorate the network efficiency and reduce travel time. The designed MPC based traffic control strategy proves effectiveness by creating optimal flow in the network subjected to control input constraints

    Secure NFV Orchestration Over an SDN-Controlled Optical Network With Time-Shared Quantum Key Distribution Resources

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    Quantum key distribution (QKD) is a state-of-the-art method of generating cryptographic keys by exchanging single photons. Measurements on the photons are constrained by the laws of quantum mechanics, and it is from this that the keys derive their security. Current public key encryption relies on mathematical problems that cannot be solved efficiently using present-day technologies; however, it is vulnerable to computational advances. In contrast QKD generates truly random keys secured against computational advances and more general attacks when implemented properly. On the other hand, networks are moving towards a process of softwarization with the main objective to reduce cost in both, the deployment and in the network maintenance. This process replaces traditional network functionalities (or even full network instances) typically performed in network devices to be located as software distributed across commodity data centers. Within this context, network function virtualization (NFV) is a new concept in which operations of current proprietary hardware appliances are decoupled and run as software instances. However, the security of NFV still needs to be addressed prior to deployment in the real world. In particular, virtual network function (VNF) distribution across data centers is a risk for network operators, as an eavesdropper could compromise not just virtualized services, but the whole infrastructure. We demonstrate, for the first time, a secure architectural solution for VNF distribution, combining NFV orchestration and QKD technology by scheduling an optical network using SDN. A time-shared approach is designed and presented as a cost-effective solution for practical deployment, showing the performance of different quantum links in a distributed environment

    Collaborative Virtual Environment System for Distance Education in Mathematics

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    Distance Education today is available in most countries of the world. After appearance of Internet distance education became more available and convenient because Internet is known as the largest information network and nowadays Internet is present almost in every home. Forms of Distance education can be categorized as: asynchronous and synchronous. Synchronous distance education environment can be virtual class or other virtual environment (e.g. online chat, video conferencing) where educator and educated communicate in real time. Asynchronous - email, web forum.Research presented in this thesis focuses in synchronous distance education in mathematics. The main question studied in this research is how to design learning environment for distance education in mathematics. To address this question such research areas as Computer Supported Collaborative Learning (CSCL) and some other related works are studied. CSCL is related how group of people separated by distance can learn in virtual environment collaboratively. Based on the best practices of CSCL and related works in area of distance education in mathematics, we developed concepts and presented a way which can be used to design an environment for distance education in mathematics. Designed environment is used to develop software prototype.Software prototype developed in this project named SynDiMath which is stands for Synchronous Distance Mathematics. It allows synchronous collaboration through Internet of group of participants and teachers by giving them right to use shared resources such as workspace for writing Mathematical formulas, whiteboard for drawing and fast sketching of problem, chat and computational engine. Mathematica software developed by Wolfram Research (Mathematica 5.0, 2003) is used as computational engine. Developed software allows each client (student) to have two separate workspaces. First workspace called "groupspace" where group of students together with teacher may discuss Mathematical ideas and solve problems. Second is a personal workspace called "notepad" where student may work on personal assignments and have one to one discussion with teacher. Discussion can be saved as step-by-step history and reused in future with other group of students or single student as a lesson or tutorial. Alternatively content of discussion can be saved in Hypertext Markup Language (HTML). In case of HTML content is static web page that can be included into website

    Development of a reverse supply chain model for electronic waste incorporating transportation risk

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    The quantity of Electronic waste (E-waste) is considerably growing due to the rapid development of technology. To diminish the influences of E-waste to the environment and recover raw materials, the reverse supply chain (RSC) has been examined. Most research focuses on minimizing the total cost of the system, however, does not integrate risk factors related to RSC operation. Risks generally derive from transportation activity in E-waste RSC such as delays for pick up, breakdown of trucks, the uncertainty of dangerous materials which might lead to disruptions and higher cost. Therefore, this paper aims to develop a mathematical model for minimizing the total cost of E-waste RSC which integrates transportation risk. A mixed integer linear programming is utilized in the model and addressed by an optimization software. The results of the proposed model can determine the optimal locations and the amount of used products transported within the RSC network.  The numerical example also demonstrates that the movement of materials or components in the RSC network is considerably affected by considering transportation risk. The suggested model can assist decision makers about establishing RSC network in which risk elements are incorporated

    Software network analyzer for computer network performance measurement planning over heterogeneous services in higher educational institutes

    Get PDF
    In 21st century, convergences of technologies and services in heterogeneous environment have contributed multi-traffic. This scenario will affect computer network on learning system in higher educational Institutes. Implementation of various services can produce different types of content and quality. Higher educational institutes should have a good computer network infrastructure to support usage of various services. The ability of computer network should consist of i) higher bandwidth; ii) proper network design; and iii) higher performance of communication devices/servers. Thus, presently there is no software to plan and help network administrator in determine ability of network services during introduce a new service. Current approach using by network administrators are planning computer network performance via prediction and measure ability of real network performance using hardware/software network analyzer. This approach can influence several problems such as prediction without software always inaccurate and most of the software/hardware network analyzer in real network is limited by network interfaces. Therefore, to encounter these problems, network administrators need software that can plan and measure additional network resources. Thus, this study presents a novel approach for measurement and planning network performance management in heterogeneous environment. The main objectives of this research is to i) identify which approach and problem occurs in Malaysia higher educational institutes; ii) create simulation model that able to plan and measure network performance for various services; iii) software network analyzer development based on simulation model design; and iv) conduct an evaluation of simulation model and software development with real network. These objectives can achieve as follows: i) conduct a survey; ii) select appropriate mathematical formula to create simulation model; iii) select appropriate modeling application for software development; and iv) conduct verification and validation technique for simulation modeling and evaluation of software network analyzer . The results from survey show that most of the network administrators are using hardware/software network analyzer to measure network performance during operational phase. The minimum size of bandwidth capacity has contributed higher network utilization usage. It can generate network congestion and network service failure in higher educational institutes. We create suitable models to evaluate the network performance using Little Law and Queuing theory that can represent similar to hardware/software network analyzer. In order to get accuracy results on the performance of simulation model, we measure (verify and validate) data from lab experiment and real network environment. Development of software network analyzer is based on simulation model architecture. This software will undergo evaluation process using qualitative technique. As a result, this software prototyping can provide a good approximation of real functionality observed in the real network environment. In addition the software is capable of approximating the performance within a minimum error rate. This software network analyzer can significantly enhance to analyze and propose solution on computer network performance. Future work is to develop software network analyzer for planning, suggestion and analyzing computer network performance on wireless transmission (WLAN, WWAN and WiMax) and Ipv6 protocol. We investigate how preparation and planning phases can be applied to heterogeneous environment in order to better utilize network resources. Our software network analyzer prototyping development is based on Fluke Optiview Network Analyzer. Before we develop any software prototype, it should define the following criteria: i) establish prototype objectives; ii) define prototype functionality; iii) develop prototype; and iv) evaluate prototype. Software network analyzer prototype consists of two phases: analyzing computer network performance under optimum condition and without optimum condition. Software network analyzer prototype was developed to measure and predict network activities based on offline condition. We use qualitative technique to measure our software network analyzer prototype to identify this software is able to plan, propose and analyze computer network performance. Evaluation of software network analyzer prototype is based on focus groups in University of Kuala Lumpur (UniKL). Six evaluators are experienced in education and industrial sector will select to complete the survey and interview task. Three evaluators will select who are experienced in industrial sector only, while, another three evaluators experienced in academic and industrial sector. All evaluators have experienced more than 6 to 13 years in network management field. All evaluators need to complete the following task such as: acceptance test, performance test, loading test, network responsive test and repetition test. A common strategy is to design, test, evaluate and then modify the design based on analysis of the prototype.Facultad de Informátic

    CoCalc as a Learning Tool for Neural Network Simulation in the Special Course "Foundations of Mathematic Informatics"

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    The role of neural network modeling in the learning content of the special course "Foundations of Mathematical Informatics" was discussed. The course was developed for the students of technical universities - future IT-specialists and directed to breaking the gap between theoretic computer science and it's applied applications: software, system and computing engineering. CoCalc was justified as a learning tool of mathematical informatics in general and neural network modeling in particular. The elements of technique of using CoCalc at studying topic "Neural network and pattern recognition" of the special course "Foundations of Mathematic Informatics" are shown. The program code was presented in a CoffeeScript language, which implements the basic components of artificial neural network: neurons, synaptic connections, functions of activations (tangential, sigmoid, stepped) and their derivatives, methods of calculating the network's weights, etc. The features of the Kolmogorov-Arnold representation theorem application were discussed for determination the architecture of multilayer neural networks. The implementation of the disjunctive logical element and approximation of an arbitrary function using a three-layer neural network were given as an examples. According to the simulation results, a conclusion was made as for the limits of the use of constructed networks, in which they retain their adequacy. The framework topics of individual research of the artificial neural networks is proposed.Comment: 16 pages, 3 figures, Proceedings of the 13th International Conference on ICT in Education, Research and Industrial Applications. Integration, Harmonization and Knowledge Transfer (ICTERI, 2018
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