• Title/Summary/Keyword: time constraint

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Performance Improvement of Wald Test for Resolving GPS Integer Ambiguity Using a Baseline-Length Constraint

  • Lee Eun-Sung;Chun Se-Bum;Lee Young-Jae;Kang Tea-Sam;Jee Gyu-In;Abdel-Hafez Mamoun F.
    • International Journal of Control, Automation, and Systems
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    • v.4 no.3
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    • pp.333-343
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    • 2006
  • In this paper, the baseline-length information is directly modeled as a measurement for the Wald test, which speeds up the resolution convergence of the integer ambiguity of GPS carrier phase measurements. The convergent speed improvement is demonstrated using numerical simulation and real experiments. It is also shown that the integer ambiguities can be resolved using only four actual satellite measurements with very reasonable convergence speed, if the baseline-length information is used just like one additional observable satellite measurement. Finally, it is shown that the improvement of convergence speed of the Wald test is due to the increase of the probability ratio with the use of the baseline-length constraint.

On a Two Dimensional Linear Programming Knapsack Problem with the Generalized GUB Constraint (일반화된 일반상한제약을 갖는 이차원 선형계획 배낭문제 연구)

  • Won, Joong-Yeon
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.3
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    • pp.258-263
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    • 2011
  • We study on a generalization of the two dimensional linear programming knapsack problem with the extended GUB constraint, which was presented in paper Won(2001). We identify some new parametric properties of the generalized problem and derive a solution algorithm based on the identified parametric properties. The solution algorithm has a worst case time complexity of order O($n^2logn$), where n is the total number of variables. We illustrate a numerical example.

Optimization of 3G Mobile Network Design Using a Hybrid Search Strategy

  • Wu Yufei;Pierre Samuel
    • Journal of Communications and Networks
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    • v.7 no.4
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    • pp.471-477
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    • 2005
  • This paper proposes an efficient constraint-based optimization model for the design of 3G mobile networks, such as universal mobile telecommunications system (UMTS). The model concerns about finding a set of sites for locating radio network controllers (RNCs) from a set of pre-defined candidate sites, and at the same time optimally assigning node Bs to the selected RNCs. All these choices must satisfy a set of constraints and optimize an objective function. This problem is NP-hard and consequently cannot be practically solved by exact methods for real size networks. Thus, this paper proposes a hybrid search strategy for tackling this complex and combinatorial optimization problem. The proposed hybrid search strategy is composed of three phases: A constraint satisfaction method with an embedded problem-specific goal which guides the search for a good initial solution, an optimization phase using local search algorithms, such as tabu algorithm, and a post­optimization phase to improve solutions from the second phase by using a constraint optimization procedure. Computational results show that the proposed search strategy and the model are highly efficient. Optimal solutions are always obtained for small or medium sized problems. For large sized problems, the final results are on average within $5.77\%$ to $7.48\%$ of the lower bounds.

Creating Simultaneous Story Arcs Using Constraint Based Narrative Structure (제약 조건 기반 서술구조를 이용한 동시 진행 이야기의 생성)

  • Moon, Sung-Hyun;Kim, Seok-Kyoo;Hong, Euy-Seok;Han, Sang-Yong
    • The Journal of the Korea Contents Association
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    • v.10 no.5
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    • pp.107-114
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    • 2010
  • A nonlinear story is generated through the interactivity with users using the interactive storytelling system. In a play or movie, audiences can watch one scene at a time, and in order to watch next scene, they should wait for the end of current scene. In the real world, however, various events can simultaneously happen at different places, and even those events performed by characters may dramatically affect the flow of the story. This paper suggests Constraint Based narrative structure to create such story, known as "Simultaneous Story Arcs", and "Multi Viewpoint" to simultaneously lead the direction of the stories in each place.

A Novel Method for Virtual Machine Placement Based on Euclidean Distance

  • Liu, Shukun;Jia, Weijia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.7
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    • pp.2914-2935
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    • 2016
  • With the increasing popularization of cloud computing, how to reduce physical energy consumption and increase resource utilization while maintaining system performance has become a research hotspot of virtual machine deployment in cloud platform. Although some related researches have been reported to solve this problem, most of them used the traditional heuristic algorithm based on greedy algorithm and only considered effect of single-dimensional resource (CPU or Memory) on energy consumption. With considerations to multi-dimensional resource utilization, this paper analyzed impact of multi-dimensional resources on energy consumption of cloud computation. A multi-dimensional resource constraint that could maintain normal system operation was proposed. Later, a novel virtual machine deployment method (NVMDM) based on improved particle swarm optimization (IPSO) and Euclidean distance was put forward. It deals with problems like how to generate the initial particle swarm through the improved first-fit algorithm based on resource constraint (IFFABRC), how to define measure standard of credibility of individual and global optimal solutions of particles by combining with Bayesian transform, and how to define fitness function of particle swarm according to the multi-dimensional resource constraint relationship. The proposed NVMDM was proved superior to existing heuristic algorithm in developing performances of physical machines. It could improve utilization of CPU, memory, disk and bandwidth effectively and control task execution time of users within the range of resource constraint.

The Effects of Constraint-Induced Movement Therapy on Improvement of Hand Function in Hemiplegic Side (Constraint-Induced Movement Therapy가 편마비측 손기능 증진에 미치는 영향)

  • Ryu, In-Tae;Hwang, Byong-Yong;Kim, Ji-Hye;Chung, Sang-Mi
    • The Journal of Korean Physical Therapy
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    • v.21 no.2
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    • pp.9-14
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    • 2009
  • Purpose: This study examined the effect of constraint-induced movement therapy (CIMT) on improving the hand function in hemiplegic side. Methods: Ten subjects without a control group were given CIMT to the hemiplegic side for 3 weeks. The effects of their hand function and sensibility were examined using a MAL and two point discrimination test. Repeated ANOVA was carried out for an analysis of the effects of the application of CIMT before and after treatment. Results: The participants showed significant improvement in their functional aspect with CIMT while there were no significant changes in the time domain variables. There was significant improvement in the quantitative and qualitative aspect of MAL, as well as significant improvement in the two-point discrimination function in all fingers. Conclusion: CIMT can enhance the motor function and sensory function of the hand in hemiplegic patients.

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Analysis on the Leisure Constraint and Index Concentrate Here Improvement's Leisure Activities among the Private Security Agents Applying PPA Technique (PPA기법을 적용한 민간경호경비원의 여가제약과 중점개선 여가활동 참가지수 분석)

  • Kim, Kyong-Sik;Kim, Chan-Sun;Park, Young-Man
    • The Journal of the Korea Contents Association
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    • v.10 no.7
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    • pp.317-325
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    • 2010
  • This study aims to deduct the extensive improvement types of leisure activities of private security agents using PPA technique and to examine the influence of leisure constraint on the index of participation. Through this process, this study consequently will draw the priority list of investment on the policy for improving the welfare status of private security agents. In this study, judgement sampling was applied to 6 security agencies located in Seoul, 2010, and 267 cases were used in the final analysis. Collected data went through factor analysis, reliability analysis, paired t test, PPA analysis, and regression analysis by using SPSSWIN 17.0. The conclusions were drawn as follows. In regard to the reliability, Cronbach's $\alpha$ was over .768. First, there was a difference between the preference rate and the participation rate which are the participation index of the private security agents' leisure activities. concentrate here in leisure types turned out to be fitness activities, walking/jogging, tourism, a day-long travel, and keep up the cood work in leisure types are movies, domestic tourist attractions, dating, eating out, personal relationship, watching sports, reading, karaoke, TV video watching, drinking etc. low priority in leisure types are water sports, hiking, biking, soccer, photography, ball games, sky sports, playing go/janggi, inline skates, and cooking. Second, the leisure constraint affects the participation index of leisure activities. As the personal constraint, and surrounding conscious constraint which are the subordinate factors of the leisure constraint get bigger, the participation index of favored leisure activities become lower. In contrast, when the difficulties such as structural constraint, time and economical constraint are overcome, participation index of leisure activities go on the rise.

Development of CPLD Technology Mapping Algorithm Improving Run-Time under Time Constraint (시간제약 조건하에서 수행시간을 개선한 CPLD 기술 매핑 알고리즘 개발)

  • 윤충모;김희석
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.4
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    • pp.15-24
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    • 1999
  • In this paper, we propose a new CPLD technology mapping algorithm improving run-time under time constraint. In our technology mapping algorithm, a given logic equation is constructed as the DAG type, then the DAG is reconstructed by replicating the node that outdegree is more than or equal to 2. As a result. it makes delay time and the number of CLBs, run-time to be minimized. Also, after the number of multi-level is defined and cost of each nodes is calculated, the graph is partitioned in order to fit to k that is the number of OR term within CLB. The partitioned nodes are merged through collapsing and bin packing is performed in order to fit to the number of OR term within CLB.

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Time Series Data Cleaning Method Based on Optimized ELM Prediction Constraints

  • Guohui Ding;Yueyi Zhu;Chenyang Li;Jinwei Wang;Ru Wei;Zhaoyu Liu
    • Journal of Information Processing Systems
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    • v.19 no.2
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    • pp.149-163
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    • 2023
  • Affected by external factors, errors in time series data collected by sensors are common. Using the traditional method of constraining the speed change rate to clean the errors can get good performance. However, they are only limited to the data of stable changing speed because of fixed constraint rules. Actually, data with uneven changing speed is common in practice. To solve this problem, an online cleaning algorithm for time series data based on dynamic speed change rate constraints is proposed in this paper. Since time series data usually changes periodically, we use the extreme learning machine to learn the law of speed changes from past data and predict the speed ranges that change over time to detect the data. In order to realize online data repair, a dual-window mechanism is proposed to transform the global optimal into the local optimal, and the traditional minimum change principle and median theorem are applied in the selection of the repair strategy. Aiming at the problem that the repair method based on the minimum change principle cannot correct consecutive abnormal points, through quantitative analysis, it is believed that the repair strategy should be the boundary of the repair candidate set. The experimental results obtained on the dataset show that the method proposed in this paper can get a better repair effect.

Interactive Scheduling System for Distributed Constraint Satisfaction Problem (분산 제약조건 만족 문제에 있어서의 대화형 스케줄링시스템)

  • Kim, Jin-Su
    • The Journal of Engineering Research
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    • v.6 no.1
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    • pp.5-14
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    • 2004
  • Finding a solution to a constraint satisfaction problem requires choosing values for variables so as to satisfy the constraints of the problem. A constraint is simply a logical relation among several unknowns (or variables), each taking a value in a given domain. Conventional constraint-based scheduling systems are not enough to satisfy the all constraints because there are conflicts between them. In this paper, we propose a method for interactive scheduling, which have two major problems: first, it is hard to satisfy concretely all various kinds of constraints, and second, the search space is extremely large and requires a long execution time. To solve the above problems, we introduce the Interactive Scheduling System (ISS) that interacts with the user to exchange suggestions each other. Our system is performed in two steps: knowledge base generation of an initial assignment and iterative improvement with the user(host or internet client) to satisfy the constraints. Applying our system, we actually constructed timetables for our university, where the scheduling time is considerably reduced.

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