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신규 도입차량 유지관리 기술과 품질보증 대책에 대한 고찰 (A Study on the New Rolling Stock Vehicle Maintenance Technology and Discussion on Quality Assurance Measures)

  • 최석중;김문홍;김봉래
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.27-37
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    • 2011
  • Currently, in the course of introducing rolling stocks, RAMS standard and management by system engineering method apply to rolling stock system. Technical elements and results applied in system introduction phase are just used in acquisition stage, and these are not applied to the standard in railway site. Therefore, it is difficult to apply to standardized technology and quality assurance measure. Due to the establishment of the EU, railway operation system is internationalized and the international railway standards are being discussed in various ways. In addition, standardization is expanded from manufacture to operation and maintenance. It is to provide consistent standard in quality, cost calculation of maintenance technology, maintenance technology and quality assurance in case of international railway safety incidents. Therefore, this study is to find technology, quality and cost management model to be used for choosing railway-operation guidance by considering how technologies & quality have changed in system life cycle, compared with estimated standards, based on the technologies & quality-related result in the process of getting new rolling stocks and management guidance for operation & maintenance process.

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무인 경량전철 운영을 위한 비상대응 계획 수립에 관한 연구 (A Study on Emergency Response Plan for Manless Light Rail Transit(LRT))

  • 박민규;신종현;김연웅
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.915-923
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    • 2011
  • Our country is promoting the introduction of new means of transportation due to insufficient supply according to the existing demand of road traffic. Among them, manless light railroad transit is settled down as the most definite alternative. However, new traffic systems such as manless light railroad have certain difference between characteristics of hardware and software and subway system. Therefore, there will be many differences compared to the existing contingency system when accidents occur. Railway management organization has to establish railway contingency plan and acquire permission from the minister of the Ministry of Land, Transport, and Maritime Affairs. However, as commercial transportation is available, a new traffic system also should establish contingency plan. Therefore, the establishment of systematic contingency plan is suggested in order to analyze characteristics of manless light railroad in the beginning of introduction and to make contingency response available.

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함정 격실에 적용되는 흡음재와 잔향시간에 따른 실내 소음 분석 (Investigation of the Indoor Noise of Naval Vessel according to the Sound Absorption and Reverberation Time in a Cabin)

  • 한형석;박미유;조흥기;김중길;임동빈;손윤준
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2010년도 추계학술대회 논문집
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    • pp.586-591
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    • 2010
  • The sound field can be classified to the direct and reverberant sound field. If the sound absorption material in a room is not applied sufficiently, the reverberant sound field increases and the sound pressure in a room also increases when the sound source exists in a room. Therefore, the reverberation time should be controled in order to reduce the reverberant sound as well as sound pressure level in a room. Even though the reverberation time is specified and researched widely in architectural engineering, it is rarely performed in a marine engineering. Therefore, in this research, the reverberation time in a navel vessel is researched related to the noise reduction in a cabin.

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Recent Advances in Animal Feed Additives such as Metabolic Modifiers, Antimicrobial Agents, Probiotics, Enzymes and Highly Available Minerals - Review -

  • Wenk, C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권1호
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    • pp.86-95
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    • 2000
  • Animal feed additives are used worldwide for many different reasons. Some help to cover the needs of essential nutrients and others to increase growth performance, feed intake and therefore optimize feed utilization. They can positively effect technological properties and product quality. The health status of animals with a high growth performance is a predominant argument in the choice of feed additives. In many countries the use of feed additives is more and more questioned by the consumers: substances such as antibiotics and $\beta$-agonists with expected high risks are banned in animal diets. Therefore, the feed industry is highly interested in valuable alternatives which could be accepted by the consumers. Probiotics, prebiotics, enzymes and highly available minerals as well as herbs can be seen as alternatives to metabolic modifiers and antibiotics.

한국 청소년범죄 대책방안 (A Study for Counterplan of Korean Juvenile delinquency)

  • 강경수;이민형;김진환
    • 한국재난정보학회 논문집
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    • 제4권1호
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    • pp.10-31
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    • 2008
  • Recently, 'Juvenile' is associated with the 'Misconduct', for it becomes an object of public concern. Therefore in this study, we suggest counterplan about the group traits connected juvenile-life intimately. First, parents promote conversation among the family and are concerned about their children. And they find out the problems in the bud to educate beforehand Second, the counterplan by school attaches great importance to individual contact. Third, in the counterplan on social aspects, adults' unwholesome ideas, bad effects of the mass communication, the lack of teenager's association, negative activity, leisure facilities and lack of opportunity for juveniles bring about negative facts for education of teenagers. Therefore we need positive counterplan to enlighten the young and purify the social environment. And the nation establish righteous values for the younger generation to not commit a crime and punish severely as well as must prepare the realistic and clear policy for the young to bear the responsibility for their role.

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거리에 비례하는 오차를 고려한 eLoran 항법 알고리즘 (eLoran Navigation Algorithm Considering Errors Proportional to the Range)

  • 송세필;최헌호;김영백;이상정;박찬식
    • 전기학회논문지
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    • 제60권12호
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    • pp.2326-2332
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    • 2011
  • eLoran is enhanced Loran-C and eLoran is researched for as GPS backup system because this system is resistant to signal interference and has high accuracy. TOA measurements of eLoran include errors proportional to the range such as PF, SF, ASF and EF. Therefore these error factors must be compensated for improved accuracy of position. Generally, error models or GPS aided compensation methods are used, but these methods are limited by lack of infrastructure or system performance. Therefore, this paper proposes new model of error factors included in eLoran TOA measurements and navigation algorithm using this model. Error factors in this model are sum of a certain size of error and error proportional to the range. And feasibility and performance of proposed navigation algorithm are verified by using raw measurements.

Hybrid Neural Networks for Pattern Recognition

  • Kim, Kwang-Baek
    • Journal of information and communication convergence engineering
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    • 제9권6호
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    • pp.637-640
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    • 2011
  • The hybrid neural networks have characteristics such as fast learning times, generality, and simplicity, and are mainly used to classify learning data and to model non-linear systems. The middle layer of a hybrid neural network clusters the learning vectors by grouping homogenous vectors in the same cluster. In the clustering procedure, the homogeneity between learning vectors is represented as the distance between the vectors. Therefore, if the distances between a learning vector and all vectors in a cluster are smaller than a given constant radius, the learning vector is added to the cluster. However, the usage of a constant radius in clustering is the primary source of errors and therefore decreases the recognition success rate. To improve the recognition success rate, we proposed the enhanced hybrid network that organizes the middle layer effectively by using the enhanced ART1 network adjusting the vigilance parameter dynamically according to the similarity between patterns. The results of experiments on a large number of calling card images showed that the proposed algorithm greatly improves the character extraction and recognition compared with conventional recognition algorithms.

홀로그래픽 정보저장기기의 재생 이미지 패턴을 이용한 디스크 틸트 오차 측정 (Disc Tilt Error Measurement using Reconstructed Image Pattern for Holographic Data Storage)

  • 임성용;한초록;김도형;양현석;박노철;박영필
    • 정보저장시스템학회논문집
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    • 제8권2호
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    • pp.67-71
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    • 2012
  • Page-oriented holographic data storage (HDS) is very sensitive to the tilt error. Therefore, tilt error should be measured and compensated. Especially, mechanical tilt measurement method cannot cope with tilt error measurement because photopolymer medium has shrinkage problem. Therefore, the method to solve this problem is using the reconstructed image which can represent both tilt and shrinkage effect. In this paper, we suggest disc tilt measurement algorithm using image pattern of retrieval data.

스트럿-타이 모델을 이용한 PSC 박스거더교량의 정착부 설계 연구 (A Study on Design for Anchorage Zone in PSC Box Girder Bridge Using Strut-Tie Model)

  • 이주하;윤영수;이만섭;김병석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.625-630
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    • 2002
  • PSC box girder is widely used in a domestic bridge and overpass, etc., therefore, the design and construction technique for the PSC box girder is developing day by day. Even if it were so, however, the design for anchorage zone in PSC box girder has depended on common sense and empirical results. And it is the current situation that the designer has difficulty due to inadequacy of provisions in the domestic design code and lack of understanding for behavior of anchorage zone. Besides, the design based on Leonhardt's method is being done in general, but the design may be various even for the same structure because of the difference in a way of applying. In this paper, therefore, anchorage zone in PSC box girder bridge is analyzed and designed by using strut-tie model. Adequacy for the application of strut-tie model is verified by comparison with the way used in current design practice, and this study presents that strut-tie model can be a rational and an economical design than current design methods.

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Herbs and Botanicals as Feed Additives in Monogastric Animals

  • Wenk, Caspar
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권2호
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    • pp.282-289
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    • 2003
  • Animal feed additives are used worldwide for many different reasons. Some help to cover the needs of essential nutrients and others to increase growth performance, feed intake and therefore optimize feed utilization. The health status of animals with a high growth performance is a predominant argument in the choice of feed additives. The use of feed additives is more and more questioned by the consumers. Therefore, the feed industry is highly interested in valuable alternatives which could be accepted by the consumers. Probiotics, prebiotics, enzymes and highly available minerals as well as herbs can be seen as alternatives. Herbs, spices and their extracts (botanicals) have a wide range of activities. They can stimulate feed intake and endogenous secretions or have antimicrobial, coccidiostatic or anthelmintic activity. A major field of application of herbs is the protection of animals and their products against oxidation.