• Title/Summary/Keyword: scheduling method

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A Custom Code Generation Technique for ASIPs from High-level Language (고급 언어에서 ASIP을 위한 전용 부호 생성 기술 연구)

  • Alam, S.M. Shamsul;Choi, Goangseog
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.11 no.3
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    • pp.31-43
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    • 2015
  • In this paper, we discuss a code generation technique for custom transport triggered architecture (TTA) from a high-level language structure. This methodology is implemented by using TTA-based Co-design Environment (TCE) tool. The results show how the scheduler exploits instruction level parallelism in the custom target architecture and source program. Thus, the scheduler generates parallel TTA instructions using lower cycle counts than the sequential scheduling algorithm. Moreover, we take Tensilica tool to make a comparison with TCE. Because of the efficiency of TTA, TCE takes less execution cycles compared to Tensilica configurations. Finally, this paper shows that it requires only 7 cycles to generate the parallel TTA instruction set for implementing Cyclic Redundancy Check (CRC) applications as an input design, and presents the code generation technique to move complexity from the processor software to hardware architecture. This method can be applicable lots of channel Codecs like CRC and source Codecs like High Efficiency Video Coding (HEVC).

Novel schemes of CQI Feedback Compression based on Compressive Sensing for Adaptive OFDM Transmission

  • Li, Yongjie;Song, Rongfang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.4
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    • pp.703-719
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    • 2011
  • In multi-user wireless communication systems, adaptive modulation and scheduling are promising techniques for increasing the system throughput. However, a mass of wireless recourse will be occupied and spectrum efficiency will be decreased to feedback channel quality indication (CQI) of all users in every subcarrier or chunk for adaptive orthogonal frequency division multiplexing (OFDM) systems. Thus numerous limited feedback schemes are proposed to reduce the system overhead. The recently proposed compressive sensing (CS) theory provides a new framework to jointly measure and compress signals that allows less sampling and storage resources than traditional approaches based on Nyquist sampling. In this paper, we proposed two novel CQI feedback schemes based on general CS and subspace CS, respectively, both of which could be used in a wireless OFDM system. The feedback rate with subspace CS is greatly decreased by exploiting the subspace information of the underlying signal. Simulation results show the effectiveness of the proposed methods, with the same feedback rate, the throughputs with subspace CS outperform the discrete cosine transform (DCT) based method which is usually employed, and the throughputs with general CS outperform DCT when the feedback rate is larger than 0.13 bits/subcarrier.

Image Completion using Belief Propagation Based on Planar Priorities

  • Xiao, Mang;Li, Guangyao;Jiang, Yinyu;Xie, Li;He, Ye
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.9
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    • pp.4405-4418
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    • 2016
  • Automatic image completion techniques have difficulty processing images in which the target region has multiple planes or is non-facade. Here, we propose a new image completion method that uses belief propagation based on planar priorities. We first calculate planar information, which includes planar projection parameters, plane segments, and repetitive regularity extractions within the plane. Next, we convert this planar information into planar guide knowledge using the prior probabilities of patch transforms and offsets. Using the energy of the discrete Markov Random Field (MRF), we then define an objective function for image completion that uses the planar guide knowledge. Finally, in order to effectively optimize the MRF, we propose a new optimization scheme, termed Planar Priority-belief propagation that includes message-scheduling-based planar priority and dynamic label cropping. The results of experiment show that our approach exhibits advanced performance compared with existing approaches.

Utilizing noise mapping in environmental impact assessment in a downtown development area (도심지 개발사업에 따른 환경영향평가시 소음지도 적용방안에 관한 연구)

  • Lee, Shi-Won;Chang, Seo-Il;Park, Younge-Min;Choi, Jin-Kwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.535-540
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    • 2005
  • In environmental impact assessment, noise impact assessment usually consists of three stages surveying the existing noise levels by measurements, predicting noise levels induced by construction works and predicting noise levels after the completion of project. When predicting noise level in urban area, this method does not consider acoustic phenomena like multi reflection, diffraction and absorption due to complex topographic configuration of building and terrains. For the purpose, a noise mapping tool is utilized to produce a series of noise maps, which are those for the present, for the works of construction and for the future. For accurate noise mapping, acoustical and topographic information is essential. Standard sound power levels and directivities of various construction equipments are required and scheduling of construction processes and locations of the equipments should be provided. In the case of exceeding legal limit, mitigation measures are applied to satisfy the legal limits and subsequent noise map is obtained and checked.

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A Study on the Smart STB design and operating methods using low-power technology (저전력 기술을 이용한 스마트 셋톱박스 설계 및 운영방법에 관한 연구)

  • Kim, Jeong-Jai;Yun, Jung-Mi;Lee, Sang-Hak
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.5
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    • pp.2367-2374
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    • 2011
  • Today's digital broadcasting services based on DVB-SI standard are provided a two-way broadcast. However, using the power of STB if the user does not use a waste of time spent on standby power is becoming a serious problem. Accordingly, for energy savings both at home and abroad to actively promote green policies, but highly functional STB, the internal software to automatically update the appropriate scheduling techniques are not shown, power usage does not meet the standard can. Therefore, In this paper We analyze the current STB technology and the problems, as proper use of power to the standard STB design scheme and the automatic software installation method of operation is presented.

Application of Critical Chain Project Management to Construction Project by a Case Study (사례연구를 통한 건설프로젝트에 CCPM의 적용)

  • Park Jeong-Hyun;Lee Young-Dae;Kim Young;Kim Sa-Myung;Park Hyeok
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.274-277
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    • 2003
  • The Theory of Constraints (TOC) is an approach and a philosophy that is used to develop specific management techniques. It was first popularized by the novel, The Goal, that applied the principles to operations management. Since 1997 it has found application in two areas within project management. The first application is scheduling of a single project to reduce project duration and simplify project control. there is a further application to allocate resources that are shared by concurrent project. It is the objective of this paper to explore the fundamentals of critical chain and to pursue an application of critical chain method to construction project by a case study.

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A simple method for reducing the complexity of EPLA packet scheduling algorithm (EPLA(Expected Packet Loss Amount) 패킷 스케쥴링 알고리즘의 복잡도를 줄이는 간단한 방법)

  • Lee, Young-Du;Nhan, Nguyen Thanh;Koo, In-Soo
    • Proceedings of the KIEE Conference
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    • 2008.10b
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    • pp.511-512
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    • 2008
  • EPLA 패킷 스케줄링 알고리즘은 IEEE 802.22 WRAN 시스템의 실시간 트래픽 전송 지원을 위한 패킷 스케줄링 알고리즘으로 참고문헌[4]으로 제안되었다. 패킷 기반 무선 전송 시스템에서 실시간 트래픽의 경우 짧은 데이터 유효 시간을 가지며, 만약 데이터 유효 시간이 초과할 경우 실시간 트래픽 데이터로써의 가치를 상실하기 때문에 시스템에서는 해당패킷을 전송하지 않고 제거해 버린다. 그러므로 실시간 트래픽의 중요한 서비스 품질(QoS) 인자인 요구된 패킷 손실율을 보장하기 위해서는 실시간 트래픽의 데이터 유효 시간을 고려하여 자원을 할당하여야 한다. 기존의 패킷 스케쥴링 알고리즘들은 많은 경우 큐의 맨 앞에 위치한 패킷의 지연 시간을 고려하지만 EPLA는 패킷이 저장되는 큐 내의 다음 프레임에서 제거 될 것으로 예상되는패킷의 손실양을 고려하여 자인을 할당함으로 기존의 실시간 패킷 스케줄링 알고리즘에 비해 훨씬 좋은 성능을 보인다. 하지만 EPLA는 예상되는 패킷 손실양을 계간하기 위해서 모든 사용자의 큐에 저장된 패킷들을 확인해야하므로 높은 복잡도를 가지는 문제점이 있다. 본 논문에서는 각 사용자로부터 피드백 받은 부채널의 상태 정보를 기반으로 사용자 큐를 확인하여 횟수를 제한함으로써 패킷 손실을 성능의 손실 없이 복잡도를 줄이는 간단한 방법을 제안하고, 실시간 트래픽인 음성 트래픽과 비디오 트래픽에 대한 시뮬레이션 결과를 통해 이를 확인한다.

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Study on Dispatching with Quality Assurance (품질을 고려한 작업투입에 관한 연구)

  • Ko, Hyo-Heon;Kim, Jihyun;Baek, Jun-Geol;Kim, Sung-Shick
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.1
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    • pp.108-121
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    • 2008
  • Dispatching rule for parallel machines with multi product is proposed in this paper, In current market,customer's request for higher quality is increasing, In accordance with such demand, manufacturers are focusingon improving the quality of the products. Such shift in production objective is risky. The possibility ofneglecting another important factor in customer satisfaction increases, namely due dates. From the aspect ofimproving quality, frequency of product assignment to limited number of high performance machines willincrease. This will lead to increased waiting time which can incur delays, In the case of due date orientedproduct dispatch, Products are assigned to machines without consideration for quality. Overall deterioration ofproduct quality is inevitable, In addition, Poor products will undergo rework process which can increase delays.The objective of this research is dispatching products to minimize due date delays while improving overallquality. Quality index is introduced to provide means of standardizing product quality. The index is used toassure predetermined quality level while minimizing product delays when dispatching products. Qualitystandardization method and dispatching algorithm is presented. And performance evaluation is performed withcomparison to various dispatching methods.

Probabilistic Generation Modeling in Electricity Markets Considering Generator Maintenance Outage (전력시장의 발전기 보수계획을 고려한 확률적 발전 모델링)

  • Kim Jin-Ho;Park Jong-Bae
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.8
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    • pp.418-428
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    • 2005
  • In this paper, a new probabilistic generation modeling method which can address the characteristics of changed electricity industry is proposed. The major contribution of this paper can be captured in the development of a probabilistic generation modeling considering generator maintenance outage and in the classification of market demand into multiple demand clusters for the applications to electricity markets. Conventional forced outage rates of generators are conceptually combined with maintenance outage of generators and, consequently, effective outage rates of generators are newly defined in order to properly address the probabilistic characteristic of generation in electricity markets. Then, original market demands are classified into several distinct demand clusters, which are defined by the effective outage rates of generators and by the inherent characteristic of the original demand. We have found that generators have different effective outage rates values at each classified demand cluster, depending on the market situation. From this, therefore, it can be seen that electricity markets can also be classified into several groups which show similar patterns and that the fundamental characteristics of power systems can be more efficiently analyzed in electricity markets perspectives, for this classification can be widely applicable to other technical problems in power systems such as generation scheduling, power flow analysis, price forecasts, and so on.

Study on weather Probability for Optimum Scheduling of Rice Harvesting Mechanization. (벼 수확기계의 적정소요능력 결정을 위한 작업가능 일수의 확률분포 분석)

  • 이종호;정창주
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.17 no.2
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    • pp.3772-3777
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    • 1975
  • This paper reports on the analysis of the distributions of probable days being good for mechanical rice harvesting and the method of determining the capacity of rice harvesting machinery for the given harvesting duration. In the analysis of the probability distribution of days being good for rice harvesting, the daily rainfalls above which mechanical field work may be impracticable were specified and their frequency of occurances was analyzed by using the weather records during past twenty-one years measured at five different locations. The conclusions being drawn from the analysis are as follows: 1. The distributions of probable workable days in different region and harvesting duration are very distinct and are different to set a uniform trend (refer to Fig. 1-4). 2. The occurance of probable days being good for mechanical field work under 66% confidence level are quite variable by region and by ten-day period. The analysis indicates that the probable workable days may range from 7.5 to 8.5 days of 10-day span within optimum harvesting duration (refer to Table 1). 3. Based on the probability distributions analyzed, the optimun capacities of harvesting machinery required for different harvesting areas and harvesting start-date were estimated as a function of operating duration (refer to Fig. 5 and Table 2)

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