• 제목/요약/키워드: Over-Requirement

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An Enhanced Searching Algorithm over Unstructured Mobile P2P Overlay Networks

  • Shah, Babar;Kim, Ki-Il
    • Journal of information and communication convergence engineering
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    • v.11 no.3
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    • pp.173-178
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    • 2013
  • To discover objects of interest in unstructured peer-to-peer networks, the peers rely on flooding query messages which create incredible network traffic. This article evaluates the performance of an unstructured Gnutella-like protocol over mobile ad-hoc networks and proposes modifications to improve its performance. This paper offers an enhanced mechanism for an unstructured Gnutella-like network with improved peer features to better meet the mobility requirement of ad-hoc networks. The proposed system introduces a novel caching optimization technique and enhanced ultrapeer selection scheme to make communication more efficient between peers and ultrapeers. The paper also describes an enhanced query mechanism for efficient searching by applying multiple walker random walks with a jump and replication technique. According to the simulation results, the proposed system yields better performance than Gnutella, XL-Gnutella, and random walk in terms of the query success rate, query response time, network load, and overhead.

A New Algorithm for Unit Commitment (기동정지계획의 새로운 해법)

  • Lee, Sang-Do;Baek, Young-Sik
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.704-706
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    • 1996
  • This paper presents a new algorithm of unit commitment for optimal operation in power system. The proposed method developed algorithm that determined generators considering load variations at each stages. It has established forecast unit commitment over time horizon at first and next calculated quality cost of generators and then committed generator that has minimum quality cost at unit commitment schedule over time horizon. It is used that Objet-Oriented Programming for effective realization, and simple handling of complex program. The proposed method has applied at example system and the results has shown superior economics and computational requirement than the conventional method.

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A Study on the Optimization of IoU (IoU의 최적화에 관한 연구)

  • Xu, Xin
    • Proceedings of the Korea Information Processing Society Conference
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    • 2020.05a
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    • pp.595-598
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    • 2020
  • IoU (Intersection over Union) is the most commonly used index in target detection. The core requirement of target detection is what is in the image and where. Based on these two problems, classification training and positional regression training are needed. However, in the process of position regression, the most commonly used method is to obtain the IoU of the predicted bounding box and ground-truth bounding box. Calculating bounding box regression losses should take into account three important geometric measures, namely the overlap area, the distance, and the aspect ratio. Although GIoU (Generalized Intersection over Union) improves the calculation function of image overlap degree, it still can't represent the distance and aspect ratio of the graph well. As a result of technological progress, Bounding-Box is no longer represented by coordinates x,y,w and h of four positions. Therefore, the IoU can be further optimized with the center point and aspect ratio of Bounding-Box.

Yi et al.'s Group Key Exchange Protocol : A Security Vulnerability and its Remediation (Yi등이 제안한 그룹 키 교환 프로토콜의 보안 취약성 및 개선 방법)

  • Lee, Young-Sook;Kim, Jee-Yeon;Won, Dong-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.4
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    • pp.91-98
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    • 2012
  • A group key exchange (GKE) protocol is designed to allow a group of parties communicating over a public network to establish a common secret key. As group-oriented applications gain popularity over the Internet, a number of GKE protocols have been suggested to provide those applications with a secure multicast channel. Among the many protocols is Yi et al.'s password-based GKE protocol in which each participant is assumed to hold their individual password registered with a trusted server. A fundamental requirement for password-based key exchange is security against off-line dictionary attacks. However, Yi et al.'s protocol fails to meet the requirement. In this paper, we report this security problem with Yi et al.'s protocol and show how to solve it.

Web-shear capacity of prestressed hollow-core slab unit with consideration on the minimum shear reinforcement requirement

  • Lee, Deuck Hang;Park, Min-Kook;Oh, Jae-Yuel;Kim, Kang Su;Im, Ju-Hyeuk;Seo, Soo-Yeon
    • Computers and Concrete
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    • v.14 no.3
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    • pp.211-231
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    • 2014
  • Prestressed hollow-core slabs (HCS) are widely used for modern lightweight precast floor structures because they are cost-efficient by reducing materials, and have excellent flexural strength and stiffness by using prestressing tendons, compared to reinforced concrete (RC) floor system. According to the recently revised ACI318-08, the web-shear capacity of HCS members exceeding 315 mm in depth without the minimum shear reinforcement should be reduced by half. It is, however, difficult to provide shear reinforcement in HCS members produced by the extrusion method due to their unique concrete casting methods, and thus, their shear design is significantly affected by the minimum shear reinforcement provision in ACI318-08. In this study, a large number of shear test data on HCS members has been collected and analyzed to examine their web-shear capacity with consideration on the minimum shear reinforcement requirement in ACI318-08. The analysis results indicates that the minimum shear reinforcement requirement for deep HCS members are too severe, and that the web-shear strength equation in ACI318-08 does not provide good estimation of shear strengths for HCS members. Thus, in this paper, a rational web-shear strength equation for HCS members was derived in a simple manner, which provides a consistent margin of safety on shear strength for the HCS members up to 500 mm deep. More shear test data would be required to apply the proposed shear strength equation for the HCS members over 500 mm in depth though.

Modelling Pasture-based Automatic Milking System Herds: Grazeable Forage Options

  • Islam, M.R.;Garcia, S.C.;Clark, C.E.F.;Kerrisk, K.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.5
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    • pp.703-715
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    • 2015
  • One of the challenges to increase milk production in a large pasture-based herd with an automatic milking system (AMS) is to grow forages within a 1- km radius, as increases in walking distance increases milking interval and reduces yield. The main objective of this study was to explore sustainable forage option technologies that can supply high amount of grazeable forages for AMS herds using the Agricultural Production Systems Simulator (APSIM) model. Three different basic simulation scenarios (with irrigation) were carried out using forage crops (namely maize, soybean and sorghum) for the spring-summer period. Subsequent crops in the three scenarios were forage rape over-sown with ryegrass. Each individual simulation was run using actual climatic records for the period from 1900 to 2010. Simulated highest forage yields in maize, soybean and sorghum- (each followed by forage rape-ryegrass) based rotations were 28.2, 22.9, and 19.3 t dry matter/ha, respectively. The simulations suggested that the irrigation requirement could increase by up to 18%, 16%, and 17% respectively in those rotations in El-Nino years compared to neutral years. On the other hand, irrigation requirement could increase by up to 25%, 23%, and 32% in maize, soybean and sorghum based rotations in El-Nino years compared to La-Nina years. However, irrigation requirement could decrease by up to 8%, 7%, and 13% in maize, soybean and sorghum based rotations in La-Nina years compared to neutral years. The major implication of this study is that APSIM models have potentials in devising preferred forage options to maximise grazeable forage yield which may create the opportunity to grow more forage in small areas around the AMS which in turn will minimise walking distance and milking interval and thus increase milk production. Our analyses also suggest that simulation analysis may provide decision support during climatic uncertainty.

Examination of lysine requirement of healthy young male adults on a Chinese habitual diet by the modified indicator amino acid oxidation method

  • Tian, Ying;Peng, Jing;Chen, Yu;Gong, Junjun;Xu, Huiqing
    • Nutrition Research and Practice
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    • v.8 no.1
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    • pp.59-65
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    • 2014
  • There is currently no reference for intake of lysine for Chinese people; therefore, the present study was conducted to determine the lysine requirement of Chinese young male adults on a habitual Chinese mixed diet based on the modified indicator amino acid oxidation method. Seven young men with a mean age of $23.7{\pm}2.2$ years that were healthy based on questionnaire, physical examinations and screening tests were evaluated. Subjects were evaluated over five consecutive 7 day periods, during which time they were administered decreasing amounts of lysine via the diet (65, 55, 45, 35, $25mg{\cdot}kg^{-1}{\cdot}d^{-1}$). Subjects were allowed to adapt from day 1 to 6 and the isotopes were measured on day 7 in each period. The subjects' body weights, body compositions and plasma proteins were also examined during the study. Amino acid kinetics were measured based on the indicator amino acid oxidation technique using the $^{13}CO_2$ release rate and phenylalanine oxidation rate to estimate lysine requirements. Body weights, body compositions, and plasma proteins of subjects did not change significantly relative to those at baseline. The mean and the upper 95% CI of lysine requirements of Chinese habitual diets were determined to be 58.41 and $70.09mg{\cdot}kg^{-1}{\cdot}d^{-1}$, respectively, based on the $^{13}CO_2$ release rate and 54.28 and $65.14mg{\cdot}kg^{-1}{\cdot}d^{-1}$, respectively, based on the phenylalanine oxidation rate.

A Study on the Cognition and Requirement among the Interior Design Field Workers to Vocational High School Graduate (실업계 고등학교 실내디자인 전공 졸업생에 대한 산업현장의 인식 및 요구에 관한 연구)

  • 오혜경;김대년;천진희
    • Korean Institute of Interior Design Journal
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    • no.29
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    • pp.11-18
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    • 2001
  • The purpose of this study is to desirable curriculum for interior design major in vocational high school in order to enhance their competitiveness. The study has been carried out by surveying the cognition and requirement among the people who are working in interior design field. The major findings from the survey research are summarized as follows : 1) Hiring vocational high school graduate is positively responded over sixty percentage. The main reason to hire interior design major in vocational school is because of firm believing their capabilities and their own specialties rather than academic degree. 2) It is believed that new vocational high school graduate is lacking behind in most area at the beginning comparing with new college graduate. However it is believed that high school graduate will become equal to the college graduate after a few years and they are more specialized in certain area that college graduate. 3) The most recommendable area for the vocational high school graduate are CAD and Interior Construction Work. 4) The appropriate text book content of (:AD and interior construction work based on the requirement from the industry are as follows ; Regarding to CAD, a specialized textbook for CAD should be written. It is desirable to) educate how to express plan, elevation, perspective drawing and how to develop the presentation skills. Regarding to the Interior Construction Work desirable to develop a specialized textbook and include on the job training program. On the job training is expected to give a practical knowledge and experience by monitoring and drawing by himself every steps from the architectural area to the material selection.

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Climatic Influence on the Water Requirement of Wheat-Rice Cropping System in UCC Command Area of Pakistan (파키스탄 UCC 관개지역 밀·쌀 재배 필요수량에 대한 기후변화 영향)

  • Ahmad, Mirza Junaid;Choi, Kyung Sook
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.5
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    • pp.69-80
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    • 2018
  • This study investigated climate change influences over crop water requirement (CWR) and irrigation water requirement (IWR) of the wheat-rice cropping system of Upper Chenab Canal (UCC) command in Punjab Province, Pakistan. PRECIS simulated delta-change climate projections under the A1B scenario were used to project future climate during two-time slices: 2030s (2021-2050) and 2060s (2051-2080) against baseline climatology (1980-2010). CROPWAT model was used to simulate future CWRs and IWRs of the crops. Projections suggested that future climate of the study area would be much hotter than the baseline period with minor rainfall increments. The probable temperature rise increased CWRs and IWRs for both the crops. Wheat CWR was more sensitive to climate-induced temperature variations than rice. However, projected winter/wheat seasonal rainfall increments were satisfactorily higher to compensate for the elevated wheat CWRs; but predicted increments in summer/rice seasonal rainfalls were not enough to complement change rate of the rice CWRs. Thus, predicted wheat IWRs displayed a marginal and rice IWRs displayed a substantial rise. This suggested that future wheat production might withstand the climatic influences by end of the 2030s, but would not sustain the 2060s climatic conditions; whereas, the rice might not be able to bear the future climate-change impacts even by end of the 2030s. In conclusion, the temperature during the winter season and rainfall during the summer season were important climate variables controlling water requirements and crop production in the study area.

Performance Analysis on Integrated Ship Area Network (선박 통합 네트워크 구조 성능 분석)

  • Lee, Sung-Hyung;Kim, Jae-Hyun;Moon, Kyoung-Deuk;Lee, Kwangil;Park, Jun Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.3
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    • pp.247-253
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    • 2013
  • This paper analyzes ship area network(SAN) with integrated gateway. For the analysis, this paper analyzes reference network architecture, end-to-end connection model, traffic model, and requirement of SAN. Also, the type of network element and minimum performance of integrated gateway is derived by ship area network simulator. The performance evaluation results show that a integrated gateway operating as network switch with performance over than 30,000 packets/sec can provides end-to-end connection with satisfaction of requirement of each end-to-end connection.