• Title/Summary/Keyword: worst performance index

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A study on improving the IUU Fishing Index of Korea's distant water fisheries (한국의 원양어업 IUU어업지수 개선방안 연구)

  • Zang Geun KIM;Youjung KWON;Haewon LEE;Doo Nam KIM;Jaebong LEE
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.362-376
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    • 2023
  • The IUU Fishing Index is composed of 40 indicators. These indicators were grouped by state responsibilities (flag, coastal, port, and general including market) defined in the FAO IPOA-IUU (2001) and then by type into vulnerability, prevalence, and response. A total of 152 coastal nations was surveyed. Korea's total combined IUU Fishing Index was 2.49 in 2019 and 2.91 in 2021, indicating a drop in the ranking to the third worst out of 152 countries followed by China and Russia in 2021. The indicators that increased the IUU fishing risk in 2021 compared to 2019 included seven indicators of prevalence and two indicators of response while those reducing the risk included one prevalence and one response indicator. The IUU Fishing Index revealed that many fisheries observers and monitoring, control and surveillance (MCS) practitioners active in the waters of RFMOs jurisdiction where Korean distant water vessels operate have mentioned concerns about the compliance with RFMO conservation measures or fishing practices. It suggested that strengthening management intervention in the fishing sector is needed. The primary tool for management is the MCS system. Given the logistical difficulty of oversight from land, air and at-sea, there is a need to enhance MCS strategies through logbook data, at-sea observer and electronic monitoring program. It also suggested that MSC fisheries certification and fisheries improvement projects, which are widely used for improving fishing sector performance, could contribute to the eradication of IUU fishing and the promotion of sustainable distant water fisheries.

DEVS 형식론을 이용한 다중프로세서 운영체제의 모델링 및 성능평가

  • 홍준성
    • Proceedings of the Korea Society for Simulation Conference
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    • 1994.10a
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    • pp.32-32
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    • 1994
  • In this example, a message passing based multicomputer system with general interdonnedtion network is considered. After multicomputer systems are developed with morm-hole routing network, topologies of interconecting network are not major considertion for process management and resource sharing. Tehre is an independeent operating system kernel oneach node. It communicates with other kernels using message passingmechanism. Based on this architecture, the problem is how mech does performance degradation will occur in the case of processor sharing on multicomputer systems. Processor sharing between application programs is veryimprotant decision on system performance. In almost cases, application programs running on massively parallel computer systems are not so much user-interactive. Thus, the main performance index is system throughput. Each application program has various communication patterns. and the sharing of processors causes serious performance degradation in hte worst case such that one processor is shared by two processes and another processes are waiting the messages from those processes. As a result, considering this problem is improtant since it gives the reason whether the system allows processor sharingor not. Input data has many parameters in this simulation . It contains the number of threads per task , communication patterns between threads, data generation and also defects in random inupt data. Many parallel aplication programs has its specific communication patterns, and there are computation and communication phases. Therefore, this phase informatin cannot be obtained random input data. If we get trace data from some real applications. we can simulate the problem more realistic . On the other hand, simualtion results will be waseteful unless sufficient trace data with varisous communication patterns is gathered. In this project , random input data are used for simulation . Only controllable data are the number of threads of each task and mapping strategy. First, each task runs independently. After that , each task shres one and more processors with other tasks. As more processors are shared , there will be performance degradation . Form this degradation rate , we can know the overhead of processor sharing . Process scheduling policy can affects the results of simulation . For process scheduling, priority queue and FIFO queue are implemented to support round-robin scheduling and priority scheduling.

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Performance of SE-MMA Blind Adaptive Equalization Algorithm in QAM System (QAM 시스템에서 SE-MMA 블라인드 적응 등화 알고리즘의 성능)

  • Lim, Seung-Gag;Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.3
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    • pp.63-69
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    • 2013
  • This paper related with the performance of SE-MMA (Signed-Error MMA) that is the reduction of computational operation number in algorithm than MMA blind eualization algorithm which are possible to elimination of intersymbol interferance in the band limited and time dispersive nonlinear communication channel. In MMA algorithm which are possible to reduction of amplitude and phase rotation by intersymbol interference that is occurred in channel without using the training sequence, it uses the error signal that is the difference of the equalizer output and constant modulus, the statisticlly characteristic of transmitted signal. But in SE-MMA, it uses the polarity of the error signal, then it is possible to reduce the updating the tap coefficient and to simplify the H/W implementation. The computer simulation were performed in order to compare the performance of SE-MMA and conventional MMA algorithm. For this, the recovered signal constellation that is the output of the equalizer, the convergence performance by MSE, MD (maximum distortion) and residual isi characteristic learning curve, SER were used. As a result of simulation, the SE-MMA has more fast convergence speed than the MMA. But in the other index after reaching the seady state, it gives more worst performance values in the used index.

Development and Validation of Situation Awareness Tests for Commercial Drivers (사업용 운전자를 위한 상황인식 검사의 개발과 타당화)

  • Lee, Gyeong-Su;Gang, Ui-Jin;Park, Sang-Hyeok;Jeong, Hye-Seung;Lee, Yong-Chan;Son, Yeong-U
    • Journal of Korean Society of Transportation
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    • v.29 no.6
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    • pp.25-37
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    • 2011
  • This research aimed to investigate whether commercial drivers' situation awareness ability is related to their frequency and magnitude of caused accidents and penalty points. For the purpose of measuring drivers' situation perception and interpretation capacities, two tests named 'situation awareness test' and 'hazard perception test' were developed. The tests were based on the data from 299 commercial drivers (test drivers) using a driving simulator. The outcome of drivers' performance on situation awareness and hazard perception tests was designed to be categorized into 5 grades, classifying the best as grade 1 and the worst as grade 5. As the result, low grades on situation awareness test had positive relationship with accumulated penalty points, frequency of accidents and safety index. Grades on hazard perception test were also positively correlated with accident frequency and safety indices. This suggests situation awareness ability of commercial drivers is significantly related to traffic violations and accident causing tendencies.

Performance of a Hybrid DS/SFH Spread Spectrum System over Nakagami Fading Channel in the Presence of Multiple Tone Jamming (다중 톤 방해신호가 존재하는 나카가미 페이딩 전송로에서 DS/SFH 복합 확산대역 시스템의 성능분석)

  • Byun, Woo-Sub;Sung, Koeng-Mo
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.8
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    • pp.8-16
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    • 1999
  • In this paper, the performance of a hybrid DS/SFH-SS(direct-sequence/slow-frequency-hopped spread-spectrum) system with coherent BPSK modulation over Nakagami fading channel in the presence of multiple tone jamming is analyzed. Because the Nakagami m-distribution can describe not only Rayleigh fading but also more general fluctuations involving a specular component by adjusting the value of the fading index m. It is known that for m=1 corresponds to Rayleigh fading, for $1/2{\le}m{\le}1$ corresponds to the worst case fading condition, for m>1 corresponds to Rician fading, and for $m{\to}{\infty}$ corresponds to the nonfading condition. The bit error probability is derived over Nakagami model and numerical evaluations are presented for some combinations of system parameters. The results show that as m increases, the bit error probability is better. Also, at a low JSR(jamming-to-signal power ratio), a pure DS-SS system can achieve lower bit error probability than a hybrid DS/SFH-SS system. But at a high JSR, a hybrid DS/SFH-SS system is shown to be superior to a pure DS-SS system. Therefore, it is demonstrated that without increasing the total system bandwidth, the performance of a hybrid DS/SFH-SS is superior to that of a pure DS-SS system in the presence of multiple tone jamming.

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R&D Efficiency and Productivity in Korea, Japan and China (한·중·일 연구개발투자의 효율성 및 생산성변화 비교 분석)

  • Cho, Yun Ki
    • International Area Studies Review
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    • v.14 no.2
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    • pp.43-60
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    • 2010
  • This paper measures R&D efficiency and productivity changes of 24 nations including Korea, Japan and China by the non-parametric Malmquist productivity index. The principle findings of this study are as follows. First, R&D efficiency scores of Korea and Japan are 0.837 and 0.834 respectively. Meanwhile China shows 0.420, the worst performance among the selected countries. Second, Korea marked annual productivity increase of 25%, highest among the selected countries', for 2000-2005. R&D productivity in Japan and China, however, decreased 1.9% and 0.9% respectively. Third, annual rates of technology change and technical efficiency change in Japan are 0.6% and -2.5%. Therefore decrease of productivity in Japan is mainly due to technical inefficiency. In case of China, improvement of technical efficiency is the main contributor to productivity growth but technical progress has edged downward in the sample period. In Korea, with annual rate of technology change and technical efficiency change being 5.2% and 18.2% respectively, both efficiency improvement and technical progress has pulled the R&D productivity growth.

Effects of Arc Number or Rotation Range upon Dose Distribution at RapidArc Planning for Liver Cancer (간암환자를 대상으로 한 래피드아크 치료계획에서 아크수 및 회전범위가 선량분포에 미치는 영향)

  • Park, Hae-Jin;Kim, Mi-Hwa;Chun, Mi-Son;Oh, Yeong-Teak;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.21 no.2
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    • pp.165-173
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    • 2010
  • In this paper, we evaluated the performance of 3D CRT, IMRT and three kind of RA plannings to investigate the clinical effect of RA with liver cancer case. The patient undergoing liver cancer of small volume and somewhat constant motion were selected. We performed 3D CRT, IMRT and RA plannings such as 2RA, limited triple arcs (3RA) and 3MRA with Eclipse version 8.6.15. The same dose volume objectives were defined for only CTV, PTV and body except heart, liver and partial body in IMRT and RA plannings. The steepness of dose gradient around tumor was determined by the Normal Tissue Objective function with the same parameters in place of respective definitions of dose volume objectives for the normal organs. The approach between the defined dose constraints and the practical DVH of CTV, PTV and Body was the best in 3MRA and the worst in IMRT. The DVHs were almost the same among RAs. Plans were evaluated using Conformity Index (CI), Homogeneity Index (HI) and Quality of coverage (QoC) by RTOG after prescription with dose level surrounding 98% of PTV in the respective plans. As a result, 3MRA planning showed the better favorable indices than that of the others and achieved the lowest MUs. In this study, RA planning is a technique that is possible to obtain the faster and better dose distribution than 3D CRT or IMRT techniques. Our result suggest that 3MRA planning is able to reduce the MUs further, keeping a similar or better targer dose homogeneity, conformity and sparing normal tissue than 2RA or 3RA.

A High-speed Packet Filtering System Architecture in Signature-based Network Intrusion Prevention (시그내쳐 기반의 네트워크 침입 방지에서 고속의 패킷 필터링을 위한 시스템 구조)

  • Kim, Dae-Young;Kim, Sun-Il;Lee, Jun-Yong
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.2
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    • pp.73-83
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    • 2007
  • In network intrusion prevention, attack packets are detected and filtered out based on their attack signatures. Pattern matching is extensively used to find attack signatures and the most time-consuming execution part of Network Intrusion Prevention Systems(NIPS). Pattern matching is usually accelerated by hardware and should be performed at wire speed in NIPS. However, that alone is not good enough. First, pattern matching hardware should be able to generate sufficient pattern match information including the pattern index number and the location of the match found at wire speed. Second, it should support pattern grouping to reduce unnecessary pattern matches. Third, it should always have a constant worst-case performance even if the number of patterns is increased. Finally it should be able to update patterns in a few minutes or seconds without stopping its operations, We propose a system architecture to meet the above requirement. The system architecture can process multiple pattern characters in parallel and employs a pipeline architecture to achieve high speed. Using Xilinx FPGA simulation, we show that the new system stales well to achieve a high speed oner 10Gbps and satisfies all of the above requirements.