• 제목/요약/키워드: SoS Systems Engineering

검색결과 1,109건 처리시간 0.026초

유전 알고리즘을 이용한 최적 경로 탐색 (Searching optimal path using genetic algorithm)

  • 김경남;조민석;이현경
    • EDISON SW 활용 경진대회 논문집
    • /
    • 제4회(2015년)
    • /
    • pp.479-483
    • /
    • 2015
  • In case of the big city, choosing the adequate root of which we can reach the destination can affect the driver's condition and driving time. so it is quite important to find the optimal routes for arriving the destination as considering the factors, such as driving conditions or travel time and so on. In this paper, we develop route choice model with considering driving conditions and travel time, and it can search the optimal path which make drivers reduce their fatigues using genetic algorithm.

  • PDF

CIM구축의 타당성평가에 관한 연구 (A Study on the CIM Justification)

  • 한성배;이석주;이순효
    • 산업경영시스템학회지
    • /
    • 제18권34호
    • /
    • pp.51-60
    • /
    • 1995
  • The key competition factor of manufacturing industries has progressively changed from cost to quality and time. Recently, the manufacturing environments more rapidly change than before. So, many companies want to introduce a advanced manufacturing system like CIMS to meet various user's needs and short delivery. But there is a considerable gap between the decision to invest and the achievement of promised benefits. Managers, generally, cannot afford CIM invesment unless they can determine beforehand that CIM will work in thier company and that will provide a coherent strategy and satisfactory return on investment In many cases, it is impossible to justify CIM investment by only economical analysis. Decision making problems like CIM investment are of a multiple objective nature. So, decision making process and multiattribute utility function are very useful methods to evaluate CIM justification In this paper, we described the key functions of CIM justification evaluation using IDEF methodology and developed the applicattion procedure of DMP and MUF method for CIM justification.

  • PDF

열생성을 가진 원형발열체의 외부 유속의 영향에 대한 수치해석 (Numerical Analysis on Effect of the Environmental Velocity for Circular Heating Source with Heat Generation)

  • 배강열;지명국;정한식;정희택;정효민
    • 동력기계공학회지
    • /
    • 제8권1호
    • /
    • pp.30-35
    • /
    • 2004
  • This paper represents the numerical analysis on effect of the environmental velocity for circular heating source with heat generation. In general heating system, the oil and sheath heater is widely used, but these systems have many problems. So, the heating source with carbon ingredient has been researched in many country about manufacture, thermal and electrical properties. In this research, a circular heating source was studied through numerical analysis on several conditions of unsteady state, beat generation and environmental velocity. The temperature distributions at steady state is appeared as a non-linear pattern with variations of environmental velocity. So, the correlation equation between temperature at steady state and environmental velocity was obtained.

  • PDF

Efficient Certificateless Authenticated Asymmetric Group Key Agreement Protocol

  • Wei, Guiyi;Yang, Xianbo;Shao, Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제6권12호
    • /
    • pp.3352-3365
    • /
    • 2012
  • Group key agreement (GKA) is a cryptographic primitive allowing two or more users to negotiate a shared session key over public networks. Wu et al. recently introduced the concept of asymmetric GKA that allows a group of users to negotiate a common public key, while each user only needs to hold his/her respective private key. However, Wu et al.'s protocol can not resist active attacks, such as fabrication. To solve this problem, Zhang et al. proposed an authenticated asymmetric GKA protocol, where each user is authenticated during the negotiation process, so it can resist active attacks. Whereas, Zhang et al.'s protocol needs a partially trusted certificate authority to issue certificates, which brings a heavy certificate management burden. To eliminate such cost, Zhang et al. constructed another protocol in identity-based setting. Unfortunately, it suffers from the so-called key escrow problem. In this paper, we propose the certificateless authenticated asymmetric group key agreement protocol which does not have certificate management burden and key escrow problem. Besides, our protocol achieves known-key security, unknown key-share security, key-compromise impersonation security, and key control security. Our simulation based on the pairing-based cryptography (PBC) library shows that this protocol is efficient and practical.

동파이프 생산 설비가동의 실시간 생산정보시스템 개발 (Development of Production Information System for Real-time Operation Brass-Pipe Production Machine)

  • 정영득;김영균;박주식;강경식
    • 산업경영시스템학회지
    • /
    • 제27권1호
    • /
    • pp.1-8
    • /
    • 2004
  • This study intend to make easy modification, even if there is a new job or structure change, by modularizing program and computerize and automation of production control management used in CIM. under the condition where manager control production on the job-site, for increasing connection with other operation and management on the computer by monitoring center computer, recognizing information by computer is needed, it is possible by converting transaction. So this study goal is to make delivery control and order control fast and accurate by finding dynamic history of machine and production information in enterprise without input production and quality information by themselves with quality information system. So production increase and quality improvement are possible by diminishing manager's and producer's work with the result of the study combining POP and CIM, after that, in e-business and m-business period that every enterprise must pass, customer satisfaction and sales promotion are possible with employee's computerizing minds. these study result also can knowledge process condition with theoretical class and have a power in finding a solution with foundation of theoretical knowledge.

탄소발열체의 외부유속 및 직경변화에 대한 비정상상태에서의 수치해석적 연구 (Numerical Analysis in Unsteady State on variation of Diameter and Environmental Velocity of Carbon Heating Source)

  • 배강열;이윤환;이상용;이칠순;김봉곤;이상철
    • 동력기계공학회지
    • /
    • 제10권4호
    • /
    • pp.25-30
    • /
    • 2006
  • This paper represents the numerical analysis in unsteady state on the variation of diameter and environmental velocity of carbon heating source. In general heating system, the oil and sheath heater is widely used, but these systems have many problems. So, the heating source with carbon ingredient has been researched in many country about manufacture, thermal and electrical properties. In this research, the carbon heating source was studied through numerical analysis on several conditions of unsteady state, heat generation, diameter and environmental velocity. The temperature distributions at steady state are appeared as a non-proportional linear pattern with variations of environmental velocity due to the Nesselt number with convective heat flux is proportioned to 0.805 of Reynolds number. As the radius is increasing, the temperature distributions is appeared the minus tilt because of the environmental condition is cooling by constant temperature. So, the correlation equation between temperature at steady state and environmental velocity was obtained.

  • PDF

OTP와 일회성 난수를 사용한 AES 알고리즘 기반의 개선된 RFID 상호 인증 프로토콜 (Improved RFID Mutual Authentication Protocol using One-Time Pad and One-Time Random Number Based on AES Algorithm)

  • 윤태진;오세진;안광선
    • 한국컴퓨터정보학회논문지
    • /
    • 제16권11호
    • /
    • pp.163-171
    • /
    • 2011
  • RFID 시스템은 무선 주파수를 이용하기 때문에 도청, 위치 추적, 스푸핑 공격, 재전송 공격과 같은 공격에 취약하다. 이를 해결하고자 RFID 시스템의 상호 인증 기법과 암호화 기법이 활발히 연구되고 있다. 그러나, 과거 AES(Advanced Encryption Standard)를 이용한 대칭키 기반의 프로토콜은 고정키 문제와 보안 취약성을 안고 있어 본 논문에서 기존 프로토콜의 보안 취약성을 증명하고, OTP(One-Time Pad) 기법과 AES를 이용한 프로토콜을 제안하여 보안 취약점을 보완하고 연산, 하드웨어 오버헤드를 감소하고자 한다. 제안 프로토콜은 리더와 태그간 데이터를 암호화하고, 리더의 일회성 난수 사용하여 상호 인증을 한다. 그리고, S.Oh 프로토콜을 비롯한 기존 프로토콜과 비교 분석으로 보안성과 서버, 리더, 태그의 연산량 측면 등 효율성에서 상대적으로 우수함을 보인다.

불확실성을 갖는 비선형 시스템의 퍼지 $H^{\infty}$ 제어기 설계 (Fuzzy $H^{\infty}$ Controller Design for Uncertain Nonlinear Systems)

  • 이갑래;정은태;박홍배
    • 전자공학회논문지S
    • /
    • 제35S권6호
    • /
    • pp.46-54
    • /
    • 1998
  • 본 논문은 파라미터 불확실성을 갖는 비선형 시스템을 안정화하며, 폐루프 시스템의 외란감쇠에 대한 $L_{2}$ 이득 제한조건을 만족시키는 견실 퍼지 $H^{\infty}$ 제어기 설계기법을 제시한다. 불확실성을 갖는 비선형 시스템을 불확실성을 갖는 Takagi-Sugeno(T-S) 모델로 표현하고 병렬 분산 보상(PDC : parallel distributed compensation)의 개념을 이용하여 제어기를 설계한다. 파라미터 불확실성을 갖는 T-S 퍼지모델에 대한 감쇠율을 만족하는 폐루프 시스템의 안정성 조건과 Lyapunov 함수를 이용하여 외란감쇠 조건을 유도하고, 선형 행렬 부등식(LMI: linear matrix inequality)을 이용하여 견실 퍼지 $H^{\infty}$ 제어기가 존재할 충분조건을 구한다. 마지막으로 불확실성을 갖는 비선형 시스템에 대한 퍼지 $H^{\infty}$ 제어기 설계 예를 보인다.

  • PDF

실대화재시험의 화재성능 등급분류에 관한 연구 (Study on the combustion performance's classification system for large scale fire tests)

  • 박계원;임홍순;정재군
    • 한국화재소방학회:학술대회논문집
    • /
    • 한국화재소방학회 2008년도 추계학술논문발표회 논문집
    • /
    • pp.99-104
    • /
    • 2008
  • The combustion properties of sandwich panels were tested and analyzed according to ISO 13784-1(Room Corner Test for Sandwich panel building systems) test method for the purpose of establishing the classification of reaction to fire performance. Several variables including heat release rate, smoke production rate, FIGRA, SMOGRA, and so on, were analyzed for specific four materials about sandwich panel systems on each 5 times, totally 20 times. Finally, elements for Classification system were suggested and evaluations for those elements were made.

  • PDF

교통량과 교통하중을 고려한 교량건설비용의 할당 (An Approach for Bridge Construction Cost Allocation Considering Traffic Load and Traffic Capacity)

  • 이동주;황인극
    • 산업공학
    • /
    • 제17권2호
    • /
    • pp.142-148
    • /
    • 2004
  • The objective of bridge construction cost allocation is to distribute in a fair and rational manner the bridge construction costs among those vehicles using the bridge. In most bridge construction cost allocation studies, bridge construction costs are mainly distributed according to traffic load(gross vehicle weight), without any consideration of bridge capacity requirements(the number of lanes). In this paper, a bridge cost allocation method for considering both traffic capacity and traffic loads is developed. The proposed method is based on cooperative game theory, particularly two concepts known as the Aumann-Shapley (A-S) value and Shapley value. This method can help to analyze the impact of traffic capacity costs. By applying the proposed method to an example, traffic capacity cost is found to be high so that traffic capacity should be considered to allocate the bridge construction costs to vehicle classes in a more equitable manner.