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A study on the TradeCard System for Payment under Cyber Trading (전자무역시대에 트레이드카드 결제시스템의 경제적 효용성과 문제점)

  • 한상현
    • The Journal of Information Technology
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    • v.4 no.1
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    • pp.55-69
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    • 2001
  • TradeCard is a B2B (business-to-business) e-commerce infrastructure that enables buyers and sellers to conduct and settle international trade transactions securely over the Internet. and objective of TradeCard is to provide a secure, reliable, cost-effective and user-friendly solution for conducting and settling international trade transactions. This paper analyzes the reviews of TradeCard by Electronic Message and the various problems which come to application of TradeCard, with particular attention to existing international frameworks for payment systems based on Documentary Credit.

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Design of an Efficient Turbo Decoder by Initial Threshold Setting (초기 임계값 설정에 의한 효율적인 터보 복호기 설계)

  • 김동한;황선영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.5B
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    • pp.582-591
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    • 2001
  • 터보 부호는 반복적인 복호 알고리즘을 사용함으로써 가산성 백색 가우시안 잡음(AWGN) 채널 환경에서 Shannon 한계에 가까운 성능을 보이는 오류정정 방식으로 제안되었으나, 반복 연산량에 따른 복호 지연과 인터리버에 따른 지연에 의해 실시간 처리의 어려움이라는 문제점을 안고 있다. 본 논문에서는 터보 부호의 성능을 저하시키지 않는 범위에서 적절한 초기 임계값 설정에 따라 불필요한 반복 복호 횟수를 줄일 수 있는 터보 복호기 구조를 제안한다. 적절한 초기 임계값 설정은 LLR(Log-Likelihood Ratio)값의 평균값과 분산, 복호기의 출력에 대한 BER에 근거하여 여러 번의 모의 실험을 통해서 최적의 값으로 결정된다. 제안한 방식은 초기 임계값을 적절히 선택하면 손실이 없는 범위 내에서 반복횟수를 감소시킴으로써 기존의 정해진 반복횟수로 인한 큰 복호 지연을 미연에 방지하고, 이에 따른 계산량 감소는 저전력의 효과도 가져온다. 성능 평가를 위해 BER = $10^{-6}$이내이고, 전송속도가 32kbps 이상인 IMT2000의 고속 데이터 전송 환경에서 모의 실험을 하였다. 실험 결과로 기존의 정해진 반복횟수를 갖는 터보 복호기에 비해 SNR 변동(0~3dB)에서 평균적으로 55~90% 정도의 감소된 반복횟수를 검증하였다.

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Adverse Effects of the Megadose Perilla Oil on the Rats Metabolism (들깨기름을 다량 투여한 흰쥐에서 대사에 미치는 역작용에 관하여)

  • 서화중;서유승
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.2
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    • pp.277-283
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    • 2002
  • In the present study, adverse effects of megadose of dietary perilla oil were investigated in an experimental model consisted of 6 groups of Wistar rats. To compare the adverse effects of megadose perilla oil with different kind of dietary fat, rats were fed one of the following diets for one month: 10% beef tallow (B$_1$B), 10% corn oil (C$_1$B), 10% perilla oil (P$_1$B), 20% beef tallow (B$_2$B), 20% corn oil (C$_2$B), and 20% perilla oil (P$_2$B) diet. The body weight gain rate seemed to be more affected by the size of fat contents than the species of fat in the diet, so the body weight gain rate of 20% fat groups were significantly higher than those of 10% fat groups in spite of the larger amount of flood intake in 10% fat groups than in 20% fat groups. The levers of plasma triglyceride and total-cholesterol in 20% fat groups were significantly increased in dose dependent fashion when compared to 10% groups, the values of beef tallow (B$_2$B) group being the highest among all groups. Plasma glutainic pyruvic transferase activities and level of blood urea nitrogen had a tendency to increase along with increase of fat contents (%) in diets, the values of P$_2$B group, the highest among all groups, being beyond the normal levers. The plasma carbon dioxide concentration of P$_2$B group was the highest in all groups and exceeded the normal value, there being no significant difference among the plasma carbon dioxide concentration of others groups. The results showed that large dose and long term intake of dietary perilla oil had some adverse effects on hepatic and other organic functions in rats.

Numerical Analysis of Magneto-Optic Performance of One-Dimensional Magneto-Photonic Crystal (1차원 자성 포토닉 결정의 자기 광학 특성 수치해석)

  • 박재혁;조재경
    • Journal of the Korean Magnetics Society
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    • v.10 no.3
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    • pp.99-105
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    • 2000
  • One dimensional magneto-photonic crystal having structure of (A/B)$^{k/W}$(B/A)$^{k}$ , where M is a magnetic layer of highly Bi-substituted iron garnet, A and B are dielectric layers of $SiO_2$ and T $a_2$O$_{5/}$, and k is the stacking number of the dielectric layers, has been numerically analyzed as a function of the thickness (d$_{M}$) of M (1∼535 nm) and the stacking numer of k (5∼15). The transmittance, Faraday rotation, and figure of merit of the magneto-photonic crystal have been investigated both in the visible and infrared wavelengths. A factor of several and several tens greater Faraday rotation and figure of merit have been obtained compared to the single layer of M, at many localized modes. In the visible the maximum figure of merit of 0.15 was obtained ( = 720 nm) when k = 11 and d$_{M}$ = 375 nm with T : 0.54, $\theta$$_{F}$ = 8.13$^{\circ}$, which was a factor of 30 greater than that of single garnet layer. Much greater maximum figure of merit, 0.285, was obtained in the infrared ( = 1114 nm) when k = 11 and d$_{M}$ = 800 nm with T = 0.66, $\theta$$_{F}$ = 18$^{\circ}$, which was a factor of 100 greater than that of single garnet layer.

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Development and Validation of Predictive Model for Foodborne Pathogens in Preprocessed Namuls and Wild Root Vegetables (전처리 나물류 및 구근류에서 병원성 미생물의 성장예측모델 개발 및 검증)

  • Enkhjargal, Lkhagvasarnai;Min, Kyung Jin;Yoon, Ki Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1690-1700
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    • 2013
  • The objective of this study is to develop and validate predictive growth models for Bacillus cereus (diarrhea type) vegetative cells, spores and Staphylococcus aureus in preprocessed Namul (bracken and Chwinamul) and root vegetables (bellflower and burdock). For validation of model performance, growth data for S. aureus in preprocessed vegetables were collected at independent temperatures (18 and $30^{\circ}C$) not used in the model development. In addition, model performance of B. cereus (diarrhea type) in preprocessed vegetables was validated with an emetic type of B. cereus strain. In primary models, the specific growth rate (SGR) of the B. cereus spores was faster than that of the B. cereus vegetative cells, regardless of the kinds of vegetables at 24 and $35^{\circ}C$, while lag time (LT) of the B. cereus spores was longer than that of the B. cereus vegetative cells, except for burdock. The growth of B. cereus and S. aureus was not observed in bracken at temperatures lower than 13 and $8^{\circ}C$, respectively. The LT models for B. cereus (diarrhea type) in this study were suitable in predicting the growth of B. cereus (emetic type) on burdock and Chwinamul. On the other hand, SGR models for B. cereus (diarrhea type) were suitable for predicting the growth of B. cereus (emetic type) on all preprocessed vegetables. The developed models can be used to predict the risk of B. cereus and S. aureus in preprocessed Namul and root vegetables at the retail markets.

An x-dB Bandwidth Measurement Method for Terrestrial Digital Broadcasting Signals in the Field Environments (필드 환경에 적합한 지상파 디지털 방송 신호의 x-dB 대역폭 측정 방법)

  • Hwang, Tae-Wook;Kim, Young-Soo;Yang, Hoon-Gee;Yook, Jong-Gwan;Suh, Doug-Young;Kim, Jin-Sang
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.6 s.121
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    • pp.629-638
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    • 2007
  • The methods of bandwidth measurement in the field environments are notified in ITU-R spectrum monitoring(SM) documents. But, these methods for terrestrial DTV and T-DMB are not informed yet. The x-dB bandwidth is the most suitable method fer the bandwidth measurement of terrestrial digital broadcasting signals. So, we proposed the suitable x-dB value for x-dB bandwidth measurement of the digital broadcasting signal that is not notified in ITU-R SM documents. As a result, we derived the x dB value of -12 dB and -8 dB that can be used fer estimation of occupied bandwidth of DTV and T-DMB signals respectively by x dB bandwidth measurement in field environments.

On Comparison of Theoretical Formulars for Estimation of Highway Noise Barriers Effect (고속도로에서 방음벽 효과 예측을 위한 이론식이 비교)

  • 박충상
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1991.06a
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    • pp.113-116
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    • 1991
  • 본 논문에서는 고속 도로 주변에서 교통 소음 대책으로 사용되는 방음벽 효과에 대해 교통 소음 모델에 의한 예측값과 실측값을 비교하였다. 도로 교통 소음로서는 일본 음향 학회 모델, 국립 환경원 모델, 조한인 모델을 대상으로 하였다. 세가지 모델의 예측값과 실측값의 비교 결과, 갓길(노견)에서는 일본 음향 학회 모델과 국립 환경원 모델에 의한 예측값이 실측값과 $\pm$3.5dB(A) 차이로 비슷한 결과를 보였으며, 소음 측정 지점이 음원과 먼 경우는 속도가 빠를수록 일본 음향 학회 모델은 예측값과 실측값의 차이가 커졌다. 조한인 모델은 시가지 도로에서는 잘 맞지만 고속 도로에 적용하기에는 적합하지 않았다.

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A Study on the Abrupt Scene Change Detection Using the Features of B frame in the MPEG Sequence (MPEG에서 B 프레임의 특징을 이용한 급진적 장면전환 검출에 관한 연구)

  • Kim Joong-Heon;Jang Jong-Whan
    • The KIPS Transactions:PartB
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    • v.12B no.5 s.101
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    • pp.617-630
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    • 2005
  • General scene change detection determines the changes of a scene by using feature comparison of two continuous images that are above the fixed threshold. But existing algerian detects scene change that was used in comparing the features of two images continuously, it usually takes a lot of time in decrypting the image data and false-detection problem occurs when there is an object motion or a change of illumination. In this paper, macroblock were used to extract the information directly from the MPEG compression area and suggests algorithm that will detect scene changes more effectively. Existing algorithm have shown numerous arithmetic problems that were improved in the proposed algorithm. The existing algorithm cannot detect the changes of a scene after analyzing the relationship of the previousand futureimages while the algorithm being proposed can detect the changes of a scene continuously and resolves the problem of false-detection. To this end, the data used in general were tested to prove that this algerian would be able to detect the scene changes faster and more correctly than the existing ones. The performance of the suggested algorithm was analyzed basedontheresultsoftheexperiment. .

On the study for the Design Characteristics of the 60B2. Tyye among the Super High Speed Crafts (초고속 선형들 중 60B2형의 설계 특성에 관한 연구)

  • 구종도
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.05a
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    • pp.93-102
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    • 2001
  • 개발 목표로서, 최대 속도가 60knots인 초고속 단동 선형을 탄생시키기 위해서는 이 선형을 포함한 7척의 유사 선형들의 유체역학적인 성능에 대해 CWC에서의 모형선 시험과 computer simulation을 통해 계측값과 수치 계산값을 구하여 비교, 검토를 수행하였다. 그 결과, 60B2형이 모든 성능면에서 가장 우수하다는 평가를 얻었다. 그래서 본 논문에서는 이 선형의 설계 특성에 관해 기술하고자 한다.

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