• 제목/요약/키워드: Occupied Time

검색결과 354건 처리시간 0.031초

TCP Flows의 영향하에서 UDP 패킷손실을 줄이는 방법에 관한 연구 (The Study of the Performance Improvement of UDP Packet Loss affected by TCP Flows)

  • 조기영;문호림;김서균;남지승
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.1061-1064
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    • 1999
  • UDP has likely been used for real-time applications, such as video and audio. UDP supplies minimized transmission delay by omitting the connection setup process, flow control, and retransmission In general, more than 80 percent of the WAN resources are occupied by Transmission Control Protocol(TCP) traffic as opposed to UDP's simplicity, TCP adopts a unique flow control in this paper, I report new methods to minimize a udp packet loss considering TCP flow control on the real-time application the better performance of real time application can be obtained when they reduce a packet size and FIFO buffer scheduling method competing with TCP bandwidth for the bandwidth and buffering.

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혼파방목지에서 Tall Fescue와 두과목초 조합에 따른 가축생산성과 질병 비교 연구 II. 목초의 생산성 , 사료가치 , 식생구성율 및 토양특성에 미치는 효과 (Study on Animal Production and Disease Affected by Different Varieties of Tall Feacue and White Clover in Mixed Grazing Pasture II. Effect on pasture production, nutrutuve value, botanical composition, and soil characteristics)

  • 김문철;정창조;김규일;장덕지;김중계
    • 한국초지조사료학회지
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    • 제17권2호
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    • pp.157-166
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    • 1997
  • This study was carried out with aim to find out a tall fescue cultivar which is palatable and resistant to hot climate, and a white clover cultivar which is less competitive with other grasses. Pastures with 3 treatments (TI: Fawn, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T2: Roa, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T3 : Roa, tall fescue + Tahora, white clover + orchardgrass + perennial ryegrass) were established by oversowing. Under continuous grazing, dry matter yield, soil characteristics, botanical composition and nutrient contents of forages were investigated during the grazing seasons 60m 1994 to 1996. No significant difference were found in establishment percents, physical and chemical characteristics of soil, and nutrient contents of forages between 3 treatments(P>0.05). Dry matter yield of TI, T2 and T3 were 24,188, 23,827 and 23,578kg/ha, respectively. Fawn and Roa, tall fescue cultivars occupied 6.1 and 4.8% of the total plants in 1994, 14.4 and 11.5 % in 1995, and 28.4% and 17.7% in 1996, respectively. These results indicate that Fawn, tall fescue dominantly occupied with time more than Roa, tall fescue. There were no differences in percentage of Regal and Tahora, white clover cultivars(P > 0.05), showing 4.2 and 2.4% in 1994, 16.1 and 17.3% in 1995, and 2.4 and 1.0% in 1996, respectively. The percentage of orchardgrass on mixed pasture decreased after summer season of high temperature, but percentage of Roa, tall fescue slowly increased with time firom 1994 to 1996.

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전류모드 CMOS 4치 논리회로를 이용한 64×64-비트 변형된 Booth 곱셈기 설계 (Design of a 64×64-Bit Modified Booth Multiplier Using Current-Mode CMOS Quarternary Logic Circuits)

  • 김정범
    • 정보처리학회논문지A
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    • 제14A권4호
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    • pp.203-208
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    • 2007
  • 본 논문에서는 CMOS 다치 논리회로를 이용하여 $64{\times}64$ 비트 Modified Booth 곱셈기를 설계하였다. 설계한 곱셈기는 Radix-4 알고리즘을 이용하여 전류모드 CMOS 4치 논리회로로 구현하였다. 이 곱셈기는 트랜지스터 수를 기존의 전압모드 2진 논리 곱셈기에 비해 64.4% 감소하였으며, 내부 구조를 규칙적으로 배열하여 확장성을 갖도록 설계하였다. 설계한 회로는 2.5V의 공급전압과 단위전류 $5{\mu}A$를 사용하여, $0.25{\mu}m$ CMOS 기술을 이용하여 구현하였으며 HSPICE를 사용하여 검증하였다. 시뮬레이션 결과, 2진 논리 곱셈기는 $7.5{\times}9.4mm^2$의 점유면적에 9.8ns의 최대 전달지연시간과 45.2mW의 평균 전력소모 특성을 갖는 반면, 설계한 곱셈기는 $5.2{\times}7.8mm^2$의 점유면적에 11.9ns의 최대 전달지연시간과 49.7mW의 평균 전력소모 특성으로 점유면적이 42.5% 감소하였다.

PARKING GUIDE AND MANAGEMENT SYSTEM WITH RFID AND WIRELESS SENSOR NETWORK

  • Gue Hun Kim;Seung Yong Lee;Joong Hyun Choi;Youngmi Kwon
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.1278-1282
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    • 2009
  • In apartment type of housing, if resident's vehicle is registered in central control office and RFID TAG is issued, identification can be recognized from the time of entrance into parking lot and intelligent parking guide system can be activated based on the residents' profile. Parking Guide System leads a vehicle to the available parking space which is closest to the entrance gate of the vehicle's owner. And when residents forget where they parked their cars, they can query to the Parking Guide and Management System and get responses about the location. For the correct operation of this system, it is necessary to find out where the residents' cars have parked in real time and which lot is available for parking of other cars. RFID is very fancy solution for this system. RFID reader gathers the ID information in RFID TAGs in parked cars and updates the DB up to date. But, when non-residents' cars are parked inside apartment, RFID reader cannot identify them nor know the exact empty/occupied status of parking spaces because they don't react to RFID reader's query. So for the exact detection of empty/occupied status, we suggest the combined use of ultrasonic sensors and RFID. We designed a tree topology with intermediate data aggregators. The depth of tree is normally more than 3 from root (central office) to leaves (individual parking lots). The depth of 2 in tree topology brings about the bottleneck in communication and maintenance. We also designed the information fields used in RFID networks and Sensor Networks.

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보행통행 특성분석에 의한 보행환경개선 추진전략 연구 (A Strategy of Pedestrian Environment Improvement through the Analysis on the Walking Transportation Characteristics in a Big City)

  • 김형보;윤항묵
    • 한국항만학회지
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    • 제14권3호
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    • pp.269-278
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    • 2000
  • Today the pedestrian-related problems a key subject requiring the attention of the traffic engineers for improving the transportation system. Particularly in urban and CBD locations, the pedestrian presents an element of sharp conflict with vehicular traffic. Therefore pedestrian movements must be studied for the purpose of providing guideline for the design and operation of walking transportation systems. This paper is to address the characteristics of walking transportation in a big city. Especially the focuses are emphasized on the ratio occupied by pedestrian traffic among the whole unlinked trips in a city and walking time. The data for analysis are collected in Seoul metropolitan city through sampling 1,006 citizens. Compared with other similar research works this paper utilized diversified tools to acquire more useful results. Finally, policy directions for pedestrian environment improvement were suggested.

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Simulation-based Design Verification for High-performance Computing System

  • Jeong Taikyeong T.
    • 한국멀티미디어학회논문지
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    • 제8권12호
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    • pp.1605-1612
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    • 2005
  • This paper presents the knowledge and experience we obtained by employing multiprocessor systems as a computer simulation design verification to study high-performance computing system. This paper also describes a case study of symmetric multiprocessors (SMP) kernel on a 32 CPUs CC-NUMA architecture using an actual architecture. A small group of CPUs of CC-NUMA, high-performance computer system, is clustered into a processing node or cluster. By simulating the system design verification tools; we discussed SMP OS kernel on a CC-NUMA multiprocessor architecture performance which is $32\%$ of the total execution time and remote memory access latency is occupied $43\%$ of the OS time. In this paper, we demonstrated our simulation results for multiprocessor, high-performance computing system performance, using simulation-based design verification.

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걷고싶은 도시조성을 위한 보행 특성 연구 (A Study on the Walking Transportation Characteristics)

  • 김형보;윤항묵
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2000년도 추계학술대회논문집
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    • pp.53.2-60
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    • 2000
  • One of the elements requiring the attention of the traffic engineer is the pedestrian. Particularly in urban and CBD locations ,the pedestrian presents an element of sharp conflict with vehicular traffic. Therefore pedestrian movements must be studied for the purpose of providing guideline for the design and operation of transportation systems. This paper addressed the characteristics of walking transportation in a big city. Especially the focuses are emphasized on the ratio occupied by pedestrian traffic among the whole unlinked trips in a city and walking time. The data for analysis are gathered in Seoul metropolitan city sampling 1,006 citizens. Compared with other similar research works this paper utilized diversified tools to acquire more useful results.

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IP기반 H.264 디코더 설계를 위한 동기식 비선형 및 병렬화 파이프라인 설계 (A design of synchronous nonlinear and parallel for pipeline stage on IP-based H.264 decoder implementation)

  • 고병수;공진흥
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.409-410
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    • 2008
  • This paper presents nonlinear and parallel design for synchronous pipelining in IP-based H.264 decoder implementation. Since H.264 decoder includes the dataflow of feedback loop, the data dependency requires one NOP stage per pipelining latency to drop the throughput into 1/2. Further, it is found that, in execution time, the stage scheduled for MC is more occupied than that for CAVLD/ITQ/DF. The less efficient stage would be improved by nonlinear scheduling, while the fully-utilized stage could be accelerated by parallel scheduling of IP. The optimization yields 3 nonlinear {CAVLD&ITQ}|3 parallel (MC/IP&Rec.)| 3 nonlinear {DF} pipelined architecture for IP-based H.264 decoder. In experiments, the nonlinear and parallel pipelined H.264 decoder, including existing IPs, could deal with full HD video at 41.86MHz, in real time processing.

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급성약물중독(急性藥物中毒)에 관(關)한 조사성적(調査成績) (An Investigation on Acute Drug Intoxication)

  • 조수헌
    • Journal of Preventive Medicine and Public Health
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    • 제10권1호
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    • pp.25-33
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    • 1977
  • The epidemiological informations on 1,828 cases of acute drug intoxication admmitted to the emergency rooms of 5 general hospitals, 4 in Seoul City and 1 in Incheon City from Jan. 1974 to Dec. 1974, were reviewed for statistical analysis. More detailed information on 796 cases from 3 hospitals were available in terms of the causative agent. The general findings obtained are as follows; 1. The sex ratio of the patient is 1.26 females to 1 male and this figure is almost consistent with the reports of previous authors. 49.7% of total cases were found in the age group of 20-29, which indicate the highest in percent distribution of age. 2. The incidence of acute drug intoxication was different by the season as the highest in summer and the lowest in winter. 3. As the cause of the intoxication, the attempted suicide occupied the single highest one with 91.7%. 4. The kind of causative agents varies with seasons as more economic poisons in the summer time and more drugs in the winter time.

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한국의 개심술 현황 (Status of open heart surgery in Korea)

  • 송진천
    • Journal of Chest Surgery
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    • 제22권6호
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    • pp.996-1000
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    • 1989
  • Open heart surgery begun at 1959 in Korea. From that time to 1979, the surgery was performed below 100 cases in a year. However,that was performed above, 1,000 cases in a year from 1981. During the recent three years, i.e., 1985, 1986, and 1987, the annual operative cases were 3614,4503, and 4906, and then the mortality rates were progressively decreased to 6.2%, 5.3 %, and 5.0 %. In these time, overall mortality rate above 1 year old was 5.0 % versus that below 1 year old 17.9 9o in congenital heart diseases. These results are statistically different between two groups. Of the valvular heart disease cases, which occupied 97 % of total acquired heart disease, individual incidence was in mitral 68 %, and aortic 28%. The operative method was mainly valve replacement. Operative mortality for valve surgery in total was 4.4 %. Until 1985, bioprosthetic valve was frequently implanted but mechanical valve has been done more frequently in these days. Coronary artery bypass graft was large portion [67 * 75 %] of open heart surgery in western, but was below 1 % in Korea. However our diet patterns have been changed. Therefore we think the incidence of coronary artery disease will be increased. So we will be familiar to this field.

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