• Title/Summary/Keyword: EWM

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Random Backoff Scheme of Emergency Warning Message for Vehicle-to-Vehicle Communications (차량 간 통신에서 충돌을 완화하기 위한 랜덤 백오프 방안)

  • Byun, Jae-Uk;Kwon, Sung-Oh
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.3B
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    • pp.165-173
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    • 2012
  • In this paper, we propose a random backoff scheme for Emergency Warning Messages (EWMs) in the vehicle-to-vehicle environment. The EWMs are disseminated from a vehicle that detects an emergency situation to other vehicles in a multi-hop fashion. Since the vehicle-to-vehicle communication based on IEEE 802.11 adapts CSMA/CA, the density of vehicles increase the probability of collisions between transmissions. Moreover, in the presence of background traffic, the EWM should have a higher priority than that of other messages in neighboring vehicles. To that end, we propose the Distant-Dependent Adaptive Backoff (DDAB) scheme, which set a different contention window for random backoff depending on the distance from the sender to the receiver. In the case when a vehicle is expected to located in the outskirts of the communication boundary, the proposed scheme makes the contention window size small in order to compete the background traffic transmission. Otherwise the contention window is set to a large number to reduce the collision possibility among the EWM transmissions. Via simulations, we show that the proposed scheme performs better than the previous schemes for EWM.

The Study on Treatment of Poultry Waste by Earthworms, and the Effect of Feeding Earthworms Meal on the Performance of Broilers and Laying Hens, and Safety of Meat and Egg (지렁이를 이용한 계분처리 그리고 지렁이를 이용한 계육 및 계란의 생산과 안전성에 관한 연구)

  • Son, Jang-Ho
    • Korean Journal of Organic Agriculture
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    • v.17 no.1
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    • pp.63-82
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    • 2009
  • This review was conducted to the study on treatment of poultry waste by earthworms, and the effect of feeding earthworms meal on the performance of broilers and laying hens, and safety of meat and egg. 1. The pro-environmental chicken house was building in Daegu National University of Education, Daegu city, chicken wastes will be turn into high quality compost by vermicomposting uses earthworms in the house. 2. The earthworm meal (EWM) has a high proteinic content and a balanced amino acid and fatty acid profile, therefore most feeding applications has been evaluated with mono-gastric animals. 3. The dietary supplementations of 0.2 to 0.4% EWM were effective in improve digestibility of crude protein of diet resulted improved broiler performance in broiler chickens. 4. The supplementing 0.2 to 0.6% of earthworm meal in the laying hens diet, improves the laying performance and egg quality, especially ratio of egg yolk n-6/n-3 fatty acids contents. 5. As, Cd, Cr, Hg and Pb were detected at level of 4.41, 1.23, 1.18, 0.00 and 3.39ppm in earthworm meal, respectively, but those were not detected in the chicken meat and egg. therefore supplementing 0.6% of EWM in the chicken diet, it still did not affect meat and egg safety. 6. These results indicated that vermicompositing uses earthworms good a subject matter in the pro-environmental animal husbandry.

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Effects of Electrolytic Alkali Water Washing on Mackerel (Scomber japonicus) Muscle Protein Heat Gel Rheology (고등어육 단백질 가열겔 물성에 대한 알카리 전해수세수 효과)

  • Lee, Nahm-Gull
    • Journal of Environmental Science International
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    • v.21 no.2
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    • pp.233-240
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    • 2012
  • In this study, the alkiline water washing condition of mackerel(Scomber japonicus) dark meat was investigated to improve processing conditions of red muscle fish meat paste heating gel. Chemical alkaline water(CWM) and electrolytic alkiline water(EWM, pH 12) were used for washing the mackerel raw meat. Washed meats were minced with 2.5% salt and heated at $90^{\circ}C$/15 min to testing texture profile analysis. Moisture of CWM and EWM was increased with both washing times(p<0.05). Crude lipids and protiens were decreased with washing times. Lightness of chemical alkaline water washed mackerel heated paste gel(CWHPG) was higher than electrolytic alkaline water washed mackerel heated paste gel(EWHPG). Redness and yellowness were more decreased than control meats. Jelly strength of CWHPG and EWHPG was not increased more than 2 times wased meat and was increased with protein decrease. Texture profile analysis, max force1 of CWHPG and EWHPG was higher hardeness than the control meat except gel strains. From these results, it could be suggested that electric alkialine water washing is also effective in advance the red meat paste heating gel process of kamaboko industry.

A Study on the Adjustment Synthetic Control Chart Pattern for Detecting Shifts using Individual Observations in Start-Up Process (초기공정에서 공정변화에 대한 개별 관측치를 이용한 수정된 합성 관리도 연구)

  • 지선수
    • Journal of Korea Society of Industrial Information Systems
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    • v.7 no.4
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    • pp.53-58
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    • 2002
  • This paper presents a adjustment synthetic control chart that is an integration of the Shewhart X chart and the conforming run length(CRL) chart. The application of the adjustment synthetic control chart my therefore substantially enhance the effectiveness process control for manufacturing. In the synthetic control chart, denotes the average number of the X sample required to detect a process shift. The synthetic control chart outperforms the EWM chart and the X chart when σ is greater than 0.75σ. And the X-CRL charts suggested above evaluate using the conditional probability.

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Congestion Pricing Function of Internet Differentiated Services for Social Benefit (사회적 편익을 위한 인터넷 차등서비스의 혼잡요금함수)

  • Ji Seon-Su
    • Journal of Korea Society of Industrial Information Systems
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    • v.11 no.2
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    • pp.9-17
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    • 2006
  • Over the last couple of years, established Cumulus Pricing Scheme(CPS) has become an important research issue for efficiently charging differentiated internet services. This paper proposes the adjusted CPS technique that expressed information of over or under-use of resources in bandwidth. And, 1 propose CPS with respect to the six main pricing and charging conditions. Also, accumulation technique may indicate an information between specified charging and eventually requires to adapt the initial contract. So called red and green Cumulus Points(CP) are used to judge the behavior of customer. At this point, the actual resource consumption is described by function v(t) at time t.

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Effects of Feeding Earthworm Meal on the Meat Safety and Performance of Broiler Chicks (지렁이 분말의 급여가 계육의 안전성 및 육계의 생산성에 미치는 영향)

  • Son, Jang-Ho
    • Korean Journal of Organic Agriculture
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    • v.15 no.2
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    • pp.185-194
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    • 2007
  • This study was conducted to evaluate effects of feeding earthworm meal on the meat safety and performance of broiler chicks. A total of 60 broiler chicks at 7 days of age were fed the commercial diet and water until 47 days of age, earthworm meal divided into three treatments, 0% (control), 0.4% (treatment-1) and 0.6% (treatment-2) of dry earthworm meal. The body weight gain and feed/gain tend to be increase fed a 0.4 to 0.6% than 0% of earthworm meal. The effects tended to be higher in 0.4% than 0.6% of earthworm meal. As, Cd, Cr, Hg and Pb were detected at level of 4.41, 1.23, 1.18, 0.00 and 3.39ppm in earthworm meal, respectively, but those were not detected in the chicken meat (breast and thigh meat). It was assumed that supplementing 0.4% of earthworm meal in the broiler diet, improved the performance of broiler chicks and it still did not affect meat safety.

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Effective Emergency-Warning Message Transmission in the Vehicle-to-Vehicle Communication Environment (차량 간 통신 환경에서 효과적인 위험 경고 메시지 전송 방안)

  • Byun, Jae-Uk;Kwon, Sung-Oh
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.1B
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    • pp.1-8
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    • 2012
  • In this paper, we propose an algorithm to improve collision avoidance in Vehicle-to-Vehicle (V2V) networks based on IEEE 802.11p. Since IEEE 802.11p adopts CSMA/CA as a multiple access scheme and an emergency warning message (EWM) is delivered to behind vehicles in a multi-hop manner, due to transmission collision, the more vehicles in the vehicle chain results in a longer delay. The longer delay increases the possibility of a rear-end collision. In order to ensure message reception with low latency, we consider implicit acknowledgement of a broadcasted EWM message and propose an algorithm to reduce redundant message transactions, called Two-Way Implicit Acknowledgement (TWIA). By simulations, we show that our proposed algorithm can reduce the latency until the last car receives the message by 9% and the success rate every car receives the message within 0.7sec by 12% at 100 fixed-number-of-car environment.

Study on the Characteristics of EEG in Resting State on Visuo-Spatial Working Memory Performance (시공간 작업기억 수행능력에 따른 안정상태에서의 뇌파 특성 연구)

  • Jung, Chul-Woo;Lee, Hyeob-Eui;Wi, Hyun-Wook;Choi, Nam-Sook;Park, Pyong-Woon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.4
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    • pp.351-360
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    • 2016
  • The purpose of this study is to predict visual-spatial working memory performance through the characteristics of an electroencephalogram (EEG) in the resting state. The 31 study participants, middle school students with various to academic performance, were underwent visual-spatial working memory test in the Comprehensive Attention Test (CAT) on December in 2014. Each 7 and 6 participants were divided into an Excellent Working Memory (EWM) group and Poor Working Memory (PWM) group depending on the forward/backward working memory scores. The EEG measurements and analysis of the data from a Brain Function Tester were performed by the two groups. A Mann-Whitney Test was used to examine the statistical differences between them. The activation of high beta (${\beta}H$) at the Fp1 and Fp2 sites in the left and right hemisphere, and that of the low beta (${\beta}L$) in the right hemisphere in the EWM group was significantly higher than that in the PWM group. In conclusion, there is a correlation between the visual-spatial working memory performance and the activation of ${\beta}H$ and ${\beta}L$ in the resting state and a close correlation that of ${\beta}L$ in the right hemisphere in terms of mental activity and faculty. Therefore, the visual-spatial working memory performance can be predicted by the activation of ${\beta}H$ and ${\beta}L$ in the resting state. The activation of EEG can be applied as an assessment tool and provide basis data for visual-spatial working memory performance.

Aerodynamic Load Analysis for 1MW HAWT Blade According to IEC61400-1 (바람조건에 따른 1MW급 수평축 풍력터빈 브레이드의 하중 해석)

  • Kim, Jin;Ryu, Ki-Wahn;Lee, Chang-Su
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.06a
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    • pp.409-413
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    • 2007
  • To assure the structural integrity for the hub and low speed shaft (LSS) of the drive train, it is necessary to obtain the ultimate aerodynamic loads acting on the wind turbine blade. The aim of this study is to predict the time histories of 3 forces and 3 moments at the hub and the LSS based on the design load case of the IEC 61400-1. From the calculated results most of the load components have rotor revolution frequency whereas thrust and torque of the LSS show blade passage frequency. It turns out that the EWM wind condition involves the maximum ultimate loads at both hub and LSS of the horizontal axis wind turbine.

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Design of BLDC Motors for an Electric Bicycle and Development of their Controller (전기자전거용 BLDC 전동기 설계 및 제어기 개발)

  • Kim, Sang-Uk;Kim, So-Youl
    • Proceedings of the KIEE Conference
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    • 2001.07e
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    • pp.90-94
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    • 2001
  • The aim of this paper is twofold: The one is to design BLDC motors for an electric bicycle and the other is to develop a controller of the BLDC motors. A new BLDC Motor has a permanent magnet rotor in which the magnetic arrangement is radial to the shaft and integral to the rotor laminations instead of mounted on the perimeter of the rotor. This technique concentrates flux, giving a higher flux density than a surface-mounted PM motor and has the increase of reluctance torque. The stator of BLDC motor has parallel winding instead of interconnected wye-connection winding, allowing multi-phase separate independent controllability. It gets much more high power than wye-connection at same low voltage. The proposed controller has a technique of exited with modulation(EWM) and one H-bridge and two photo sensors per phase. Experimental results show the performance of the proposed BLDC motors for an electric bicycle.

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