• 제목/요약/키워드: On-board

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CASE 도구를 이용한 ATC 차상 소프트웨어의 UML 모델링 (Modeling of ATC On-Board Software in UML Using CASE Tool)

  • 양찬석;임재식;한재문;김치조;조용기
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.947-953
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    • 2006
  • ATC on-board equipment require realtime embedded software with high level of safety and reliability. To satisfy these requirements, many techniques are applied to the development of software during the lifecycle. In case of software modeling, object-oriented methodology is widening its niche replacing traditional structured methodology and modeling in UML using a CASE tool is a growing trend. In this paper, we modeled ATC on-board software in UML using Rhapsody, which is a modeling tool for realtime embedded software. We modeled the behavior of ATC on-board equipment based on state machine diagram and validated the model using the animation feature provided in the tool. According to our study, the CASE tool based on UML showed high level of applicability in modeling and verifying the software with complex behavioral characteristics.

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위성 운용을 위한 On-Board Control System 설계 및 구현 (Design and Implementation of On-Board Control System)

  • 신현규
    • 항공우주기술
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    • 제13권1호
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    • pp.86-95
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    • 2014
  • 위성의 임무를 성공적으로 수행하기 위해서는 복잡한 처리 절차와 이를 위한 명령이 필수적이다. 이를 위해 절대 시간 명령과 순차 명령 집합이 적용되어 위성의 운용에 사용되고 있다. 이러한 명령 체계는 순차적인 제어 흐름을 처리할 수는 있으나 해당 시점에서의 여러 조건에 대한 다양한 의사 결정 및 이에 따른 분기를 처리하기 힘들다는 단점이 있다. 이를 해결하기 위해 한국항공우주연구원 위성비행소프트웨어팀에서는 기존의 순차명령집합인 RTCS의 기본 형태를 유지하고 1 바이트의 연산 코드를 추가함으로써, 조건 판단 및 분기가 가능한 조건형 순차명령 집합인 RTCSC를 개발하였다. 여기서는 OBCP, VML 및 IP와 같은 위성 운용을 위한 On-Board Control System으로서의 RTCSC의 설계 및 그 구현에 대하여 소개한다.

AHP를 이용한 오픈소스 다기능 게시판의 평가 사례연구 (A Case Study on the Evaluation of Open Source Bulletin Board System with Multi-Function by the Analytical Hierarchy Process)

  • 심민재;장성용;이원영
    • 경영과학
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    • 제27권1호
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    • pp.91-105
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    • 2010
  • We proposed and stratified a selection standard model on Open Source Functional Board which could be found in Web. So we could grasp the weight about Performance Evaluation from the viewpoints of planners, developers, and web disigner professional of views. We suggested applying diverse measurement types in case of item which could chart Evaluation Standards on chosen sample boards. In case of item which couldn't do that, we compared and analyzed it by using selective type of 9 point scaling method on professionalists in every sample board. As a result of weight on upper estimate section of evaluation model chart, the order of importance was convenience(0.334), performance(0.333), function(0.240) and design(0.093) respectively. It indicates that there is more weight on performance and convenience which are hard to be structurally modified than designs and functions that are directly shown to the users. Also, it was evident that opposite results came out when using 9-point scale survey and measurement with objective data such as function and performance. The reason is because the surveyed subject can have his or her own subjectivity and bias unlike objective data. However, objectivity of the administrator is also an important factor thus both two perspectives have to be all considered when selecting the bulletin board.

내장형 분광광도시스템 구성에 따른 조명 영향 평가 (Evaluation of illumination effect for on-board spectrometer system)

  • 이상식;이충호
    • 한국정보전자통신기술학회논문지
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    • 제3권2호
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    • pp.18-24
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    • 2010
  • 본 연구에서는 표준 색차계와의 비교와 색상정보 좌표계 분석법을 이용하여, 비접촉 및 비파괴 측정 장치로 많은 분야에서 사용하고 있는 내장형 분광광도계의 조명 영향을 평가하였다. 본 연구에서 사용한 색상지는 표준 반사물질과 만셀 표준 색상인 빨강, 노랑, 초록, 파랑 색상지를 사용하였다. 표준 색차계 시스템 및 내장형 분광광도계 시스템을 비교 분석하기 위하여, 실험 재료 색상지를 색상지별 20번 측정하였다. 본 연구에서는 비접촉 및 비파괴 검사 장치에 내장형 분광광도계 응용에서 조명을 일정하게 공급하고 캘리브레이션을 정확하게 수행한다면, 조명의 영향을 거의 받지 않는 시스템을 구성할 수가 있을 것으로 판단되었다.

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Female Director and Tax Aggressiveness of Listed Insurance Firms: Insights from Nigeria

  • OGBEIDE, Sunday Oseiweh;ODILU, Austine
    • 웰빙융합연구
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    • 제2권2호
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    • pp.1-11
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    • 2019
  • This study empirically examined the effect of female director on tax aggressiveness of listed insurance firms in Nigeria. The main objective of this research was to empirically investigate the effect of female board members on tax aggressiveness, determine the composition and representation of female directors on the board of insurance companies, find out how tax aggressive are listed insurance firms and apply the BLAU (1977) index method to measure female director representation as a departure from conventional approaches specifically in the Nigerian context in the reference period, 2014 to 2018. The population of the study consists of all the quoted insurance firms as at 31st December, 2016. A sample of twenty eight (28) quoted insurance firms was selected and data were collected over the period. Inferential statistic consisting of the General Method of Moment was used for the data analysis. The results obtained reveal that board size is negative and exerts significant impact on tax aggressiveness in insurance firms in Nigeria. The study therefore recommends that the Federal government has to come up with a policy to respond to the marginalization of female on the insurance firm corporate board in Nigeria. The aim of this policy thrust should be targeted at reducing politics and biasness against women on the corporate boards of listed insurance firms.

고강도콘크리트 폭열 방지공법(PFB 공법)의 현장 적용성 평가에 관한 연구 (Study on Work-Efficiency in feild of PFB(POSCO E&C Fire Board) for High Sterength Concrete Spalling Control)

  • 김우재;정상진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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    • pp.173-176
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    • 2008
  • There are researches are in progress on ensuring the safety of the high impact concrete in cases of fire which is a current rising social problem and this research institute also developed PFB technology, the explosion preventing technology. PFB technology is to apply POSCO E&C Fire Board, a fireproof board, with an adhesive agent on the construction site, and this technology passed 3-hour fireproof test and this technology was proven from a previous research that the temperature of main root is maintained under 200 ℃. Therefore, tests on basic contents to be examined before the actual construction in this research by with a wooden prototype of a full scale to apply PFB technology to actual construction sites and tests are being done on the workability of fireproof board, the adhesive power, the resistance against imprint of wooden nail, the heat conductivity and etc. As the results of those tests, PFB technology was proven to have an excellent workability at a construction site and to be easy for processing and also this technology was proven to have a great the resisting power against imprint of wooden nail, so this research has confirmed that PFB technology has no problem to be applied on a construction site.

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The Influence of Coupling Coefficient between Wayside Transmitter and On-board Receiver upon Operation Characteristics of the ATS System

  • Kim, Min-Seok;Kim, Min-Kyu;Lee, Sang-Hyeok;Lee, Jong-Woo
    • International Journal of Railway
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    • 제4권1호
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    • pp.12-18
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    • 2011
  • The ATS system is used to provide wayside signaling. Currently, the oscillation frequency is set at 78[kHz] in the normal state. As the on-board receiver crosses over the wayside transmitter, the oscillation frequency is changed by capacitors of the wayside transmitter in a manner dependent on the train speed. As the oscillation frequency is changed, the waveform is modified in the wayside transmitter as well as in the on-board receiver. When there are other signal systems such as a ATO system present near the wayside transmitter, frequency interference occurs. This phenomenon arises since other signals or communication frequencies present will be included in the waveform. Trains often stop due to these other frequencies included in the waveform. In this paper, a model of the interaction between the wayside transmitter and on-board receiver is suggested and frequency response in the wayside transmitter and on-board receiver in the presence of the other signals are estimated by the coupling coefficient. Also, the coupling coefficients are estimated, and the optimal value is proposed.

Stewardship Theory and Information on Family Firm Performance in Vietnam

  • DAO, Thi Thanh Binh;HOANG, Linh Chi
    • 유통과학연구
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    • 제20권12호
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    • pp.13-22
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    • 2022
  • Purpose: The paper contributes to the existing literature on Vietnamese corporate governance and firm performance with a focus on listed family firms and the use of a more suitable econometric framework to analyze firm performance. The study investigates how family firm performance is affected by corporate governance under the standpoint of stewardship theory in Vietnam. Research design, data and methodology: With the use of different measures for firm performance (Tobin's Q, ROA, and ROE), regression models were estimated using Generalized Least Square (GLS) method on a panel data of a total of 113 listed companies during the five-year period from 2015 to 2019. Results: We found that family ownership as the main characteristic of the stewardship theory affects family firms positively. In addition, several other characteristics in corporate governance as board composition (board independence, board audits, and board committees), CEO (age and tenure) and firm characteristics (size, age, expansion, and annual sales) showed significant impacts on firm performance. Our findings also suggest that family firm performance can be either positively or negatively affected based on the characteristics of corporate governance. The findings can help companies evaluate the significance of corporate governance through deciding board structure and the selection of CEOs to match family firm characteristics. It also gives insights for investors, rating agencies, and policymakers for relevant purposes.

Nature of Company Ownership, the Dual Role of CEO and Board Chair, and R & D Investment Intensity

  • Meng, La-Mei;Byun, Hae-Young
    • 아태비즈니스연구
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    • 제11권2호
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    • pp.45-60
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    • 2020
  • Purpose - This study examines the impact of company ownership nature and of the dual role of CEO and board chair on R & D investment intensity, as well as the moderating effect of this dual role. Most previous research focused on the impact of the dual role of CEO and board chair on firm performance. Design/methodology/approach - This study uses A-share companies listed on the Shenzhen and Shanghai stock exchanges in China from 2008 to 2017. The univariate and the multivariate regression analysis were hired In order to analyze the data. Findings - The results show that there is a significant negative relationship between state-owned companies and R & D investment intensity. In addition, there is a significant positive relationship between the dual role and R & D investment intensity. The effect of state ownership on R & D investment intensity is more negative when CEO-board chair duality exists. This means that in case of state-owned companies, if CEO serves as the board chair, the propensity to invest in R&D is further reduced. Research implications or Originality - This is a pioneering study that considers the joint effect of state-owned companies and dual role on R & D investment intensity in the Chinese economy.

A Preliminary Analysis of Observing Classroom Inquiry on a Web-based Discussion Board System

  • LEE, Soo-Young;LEE, Youngmin
    • Educational Technology International
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    • 제12권2호
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    • pp.19-46
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    • 2011
  • The purpose of the study was to identify the characteristics of classroom inquiry features exhibited on a web-based discussion board, which is called the Message Board. Approximately 4,000 students from 80 schools with 60 on-line scientists were participated in the study. During the study, a total of 639 messages in the selected cluster and several patterns were identified and analyzed. Three main features of the classroom inquiry were analyzed in terms of: 1) learner gives priority to evidence in responding to questions; 2) learner formulates explanations from evidence; 3) learner communicates and justifies explanations. The results are as follow. First, once learners identified and understood the questions posed by the curriculum, they needed to collect evidence or information in responding to the questions. Depending on the question that students were given, types of evidence/data students needed to collect and how to collect the data could vary. Second, students' formulated descriptions, explanations, and predictions after summarizing evidence were observed on the Message Board. However, the extent to which students summarized evidence for descriptions, explanations, and predictions varied. In addition, students were able to make a better use of evidence over time when they formulate descriptions and explanations. Third, the Message Board was designed to allow the great amount of learner self-direction. Classroom teachers and on-line scientists played an important role in providing guidance in developing inquiry. At the same time, development of content understanding also contributed to inquiry development.