• 제목/요약/키워드: System Calls

검색결과 430건 처리시간 0.028초

DEVELOPMENT OF EMEVATOR GROUP SUPERVISIRY SYSTEM WITH FUZZY MADE

  • Park, Hee-Chul;Lee, See-Hun;Choi, Don;Woo, Kwang-Bang
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
    • /
    • pp.390-394
    • /
    • 1994
  • A elevator group supervisory system is designed to perform efficient operation of multiple elevators, and its basic function is to assign an appropriate elevator to a given hall-cell. In this paper, in order to improve elevator group control performance, we propose a new dispatching system which includes fuzzy multi-attribute decision making(MADM). In most cases, the purpose of group control is to maximize control goals as much as possible. Unfortunately, the decision of optimal elevator to a given hall cell is made with very uncertain information of the system, and some of control goals are related each other. The uncertainty is mainly resulted from car calls generated by serving hall calls. A fuzzy MADM algorithm is proposed to deal with these problems to improve system performance.

  • PDF

네트워크 카메라 기반 인스턴트 메신저의 개발에 대한 연구 (Development of Network Camera-based Instant Messenger)

  • 이강석;염창선
    • 산업경영시스템학회지
    • /
    • 제33권2호
    • /
    • pp.133-139
    • /
    • 2010
  • PC camera-based instant messenger have problems of video image break/delay and noise. The reason is caused by a composed problem that PC Camera is belong to the connected PC and operating in the PC. This research suggests an instant messenger that uses network camera connected to LAN instead of PC camera. Therefore, the instant messenger has a component that the camera is separated from PC. This research designs sequence diagram, video calls flow chart, and graphic user interface of the instant messenger. The instant messenger based on network camera provides high quality video calls service and makes it possible to call from a special remote site with real-time video image.

항공용 인터콤의 백업 모드 운용을 위한 디지털 방식의 이중화 설계 (The Digital Redundancy Design for Back-up Mode Operation of Aviation Intercom)

  • 정성재;조경학;김동혁;이성우
    • 한국항행학회논문지
    • /
    • 제26권5호
    • /
    • pp.358-364
    • /
    • 2022
  • 항공용 인터콤 시스템은 정/부조종사 간 내부 통화 및 조종사와 승무원 간 내부 통화, 초고주파 무전기(U/VHF)와 같은 통신 장비를 통한 외부 통화, 초단파전방향거리탐지기/계기착륙장치(VOR/ILS), 전술 항법 장치(TACAN)와 같은 항법 및 임무 장비 오디오 신호 모니터링, 비행 데이터기록장치(FDR) 및 자료전송 시스템(DTS)으로의 음성 녹음용 오디오 신호 출력, 항공기의 상태와 위협 등에 대한 오디오 경고음/경고 음성 발생 등 항공기 내의 모든 음성 신호에 대한 처리를 담당하는 장비이다. 이러한 항공용 인터콤은 아날로그 오디오 신호의 경우 노이즈에 민감하기 때문에 조종사 및 승무원의 임무 수행을 위해 항공기 내/외부의 전자파 노이즈로부터 오디오 신호를 보호할 수 있는 이중화 설계가 필요하다. 본 논문에서는 항공용 디지털 인터콤의 이중화를 위한 정상/백업 운용모드 및 디지털 방식의 이중화 설계 방안과 제작 및 검증 결과에 대하여 기술한다.

속도적응 핸드오프 알고리즘 분석 (Analysis of Velocity Adaptive Handoff Algorithm)

  • 김영일;진용옥
    • 한국통신학회논문지
    • /
    • 제22권4호
    • /
    • pp.748-760
    • /
    • 1997
  • The handoff failure probability has to be enhanced efficiently to enhance the performance of PCS system. In this paper a new scheme called velocity adaptive handoff algorithm for reducing handoff failure probability and maintaining the carried traffic constantly in PCS systems, by assigning low handoff threshold value for high mobility calls, and assigning high handoff threshold value for low mobility calls, is presented. The performance of evaluation of this new scheme is carried out in terms of tranffic characteristics. Also velocity estimation algorithm for this new scheme is presented. According to the result, the handoff failure probability of velocity adaptive handoff algorithm is enhanced about 60%.

  • PDF

이동 통신 사용패턴을 이용한 고객의 직업판정 (Customer′s Job Identification using the Usage Patterns of Mobile Telecommunication)

  • 이재석;조유정
    • 한국지능정보시스템학회:학술대회논문집
    • /
    • 한국지능정보시스템학회 2001년도 춘계정기학술대회
    • /
    • pp.243-252
    • /
    • 2001
  • Recently, as most companies recognize the importance of the customer relationship management, they strongly believe that they must know who their customers are. The job of a customer is very important information for us to understand the customer. However, since most customers are reluctant to reveal themselves, they do not let us know their jobs, and even provide false information about their jobs. The target domain of our research is mobile telecommunication. In this research, we developed a system that identifies the customer's job by utilizing the Call Detailed Record. From the Call Detailed Record, we extracted such variables as 'Average Monthly Payment'and 'Age of the Customer'and so forth. Moreover, we generated many summary variables and derived variables such as 'Number of Calls during Work Hours in Weekday', and 'Ratio of Calls from other Mobile Telephone'. Using artificial neural networks, we developed a two-step Job Identification System. In the first step, it identifies the four job classes then in the second step, it subdivides these four job classes into seven jobs. The accuracy of identifying the seven jobs was 69.1%.

  • PDF

Social Authority Within: Samuel Beckett's Not I

  • Noh, Aegyung
    • 영미문화
    • /
    • 제13권1호
    • /
    • pp.59-81
    • /
    • 2013
  • Samuel Beckett's literary sympathies with underdogs enslaved to authoritative figures, found in his earliest plays, continued in a more or less subdued form in his later plays: Not I is a good case in point thematizing a social authority psychologically embedded within a subject. The incessant bouts of self-defense, or confessional, which Mouth carries out on a dark stage is directed to an inner authority. In Civilization and Its Discontents (1931), Freud's diagnosis for individuals torn between the opposite calls of a social order-- which he called, by turns, civil society, civilization, and culture--and of individual freedom was a "neurosis." What Not I dramatizes seems to be this state of neurosis suffered by a subject bound to the contradictory calls of an internal social authority, which forces Mouth to carry on a confessional till she obtains a symbolically/linguistically viable social title of "I," and of her individualistic denial of the position("what?..who?..no!.. she!.."). Mouth's ordeal on stage does not signify the psychological pressure of the social system, with its disciplinary measures of guilt, justice, and punishment, triumphs over individualistic irregularities and abnormalities, for her "maddened" confession will never see its closure. The opposite psychological forces at work inside Mouth, who is both "in" and "out[side]" "this world," will keep engaging in an eternal battle. In a way, she is a perfect parable about us humans living within a system, "discontent" and hung between the contradictory calls of individualism and social collectiveness.

양서류 번식음 맵핑을 위한 무인비행장치 시스템의 정확성 검증 (Accuracy verification for unmanned aerial vehicle system for mapping of amphibians mating call)

  • 박민규;배서현
    • 한국환경복원기술학회지
    • /
    • 제25권2호
    • /
    • pp.85-92
    • /
    • 2022
  • The amphibian breeding habitat is confirmed by mating call. In some cases, the researcher directly identifies the amphibian individual, but in order to designate the habitat, it is necessary to map the mating call region of the amphibian population. Until now, it has been a popular methodology for researchers to hear mating calls and outline their breeding habitats. To improve this subjective methodology, we developed a technique for mapping mating call regions using Unmanned Aerial Vehicle (UAV). The technology uses a UAV, fitted with a sound recorder to record ground mating calls as it flies over an amphibian habitat. The core technology is to synchronize the recorded sound pressure with the flight log of the UAV and predict the sound pressure in a two-dimensional plane with probability density. For a demonstration study of this technology, artificial mating call was generated by a potable speaker on the ground and recorded by a UAV. Then, the recorded sound data was processed with an algorithm developed by us to map mating calls. As a result of the study, the correlation coefficient between the artificial mating call on the ground and the mating call map measured by the UAV was R=0.77. This correlation coefficient proves that our UAV recording system is sufficiently capable of detecting amphibian mating call regions.

상향링크 셀룰러 시스템에서 그룹 탐색 기반의 분산동적채널할당 방법 (A Group Search-based Distributed Dynamic Channel Allocation Algorithm in Uplink Cellular System)

  • 유도경;김동회
    • 방송공학회논문지
    • /
    • 제15권3호
    • /
    • pp.407-413
    • /
    • 2010
  • 주파수 재사용률 1을 사용하는 상향링크 셀룰러 시스템의 동적채널할당 (DCA : Dynamic Channel Allocation) 방법에서는 신규호가 채널 할당을 요구할 때 신규호의 SINR (Signal to Interference and Noise Ratio)이 요구된 SINR 보다 작거나 할당할 채널이 부족한 경우에 신규호 차단이 발생한다. 이러한 차단된 신규호에 대한 추가적인 채널할당을 위하여 인접한 셀에서 채널을 가져오게 된다. 이 경우에 동일 채널 간섭 (CCI: Co-Channel Interference)이 발생하게 되고 이로 인해 기존 호의 SINR이 저하되어 기존 호에 대한 채널 재할당을 해야 하는 경우가 생기게 된다. 따라서 신규호 블록율이 증가할수록 인접한 셀에서 채널을 가져오는 경우의 수를 증가시킴으로써 채널 재할당 과정은 복잡한 연산과정이 필요한 NP-hard 문제가 된다. 그 문제를 해결하기 위하여 본 논문에서는 차단된 신규호를 감소시킴으로써 추가적인 채널할당을 위하여 인접한 셀에서 채널을 가져오는 횟수를 감소시키고 그 결과로 채널 재할당 횟수가 감소되어 복잡한 연산과정을 피할 수 있는 Group Search-based DCA 방법을 제안한다. 제안한 방법은 신규호의 차단율을 감소시키기 위하여 신규호에 대한 채널할당시 단말이 속해 있는 셀뿐만 아니라 그 주변의 셀까지를 한 그룹으로 묶어서 채널 탐색 범위를 확장하는 방법을 사용한다. 시뮬레이션 결과에서 제안한 Group Search-based DCA가 탐색 범위를 단말이 속한 셀로 한정하는 Single Search-based DCA보다 신규호 차단률과 시스템 수율 성능을 향상시킴을 확인할 수 있었다.

APPROXIMATE ANALYSIS OF AN N-DESIGN CALL CENTER WITH TWO TYPES OF AGENTS

  • Park, Chul-Geun;Han, Dong-Hwan;Baik, Kwang-Hyun
    • Journal of applied mathematics & informatics
    • /
    • 제26권5_6호
    • /
    • pp.1021-1035
    • /
    • 2008
  • In this paper, we analyze an N-design call center with skill-based routing, in which one pool of agents handles two types of calls and another pool of agents handles only one type of calls. The approximate analysis is motivated by a computational complexity that has been observed in the direct stochastic approach and numerical method for finding performance measures. The workforce staffing policy is very important to the successful management of call centers. So the allocation scheduling of the agents can be considered as the optimization problem of the corresponding queueing system to the call center. We use a decomposition algorithm which divides the state space of the queueing system into the subspaces for the approximate analysis of the N-design call center with two different types of agents. We also represent some numerical examples and show the impact of the system parameters on the performance measures.

  • PDF

광대역 OFDMA 무선통신시스템의 호 접속제어에 관한 연구 (Study on the Call Admission Control in the Broadband OFDMA Wireless Communication Systems)

  • 백천현
    • 대한산업공학회지
    • /
    • 제34권4호
    • /
    • pp.445-459
    • /
    • 2008
  • This paper addresses a call admission control(CAC) scheme giving handoff calls a priority over new calls for OFDMA wireless communication systems. The characteristics of OFDMA system and a variety of user QoS (Quality of Service) requirements are incorporated into the proposed CAC scheme which consists of several optimization modules for the system resource(subcarriers and power) allocations. The mathematical models and its solution methods for the embedded resource allocation problems are proposed. Some extensive computational experiments are conducted to illustrate the superiority of our CAC.