• Smart Structures and Systems
• /
• 제16권1호
• /
• pp.163-181
• /
• 2015

This research investigates the structural health monitoring of nonlinear structures after a major seismic event. It considers the identification of flag-shaped or pinched hysteresis behavior in response to structures as a more general case of a normal hysteresis curve without pinching. The method is based on the overall least squares methods and the log likelihood ratio test. In particular, the structural response is divided into different loading and unloading sub-half cycles. The overall least squares analysis is first implemented to obtain the minimum residual mean square estimates of structural parameters for each sub-half cycle with the number of segments assumed. The log likelihood ratio test is used to assess the likelihood of these nonlinear segments being true representations in the presence of noise and model error. The resulting regression coefficients for identified segmented regression models are finally used to obtain stiffness, yielding deformation and energy dissipation parameters. The performance of the method is illustrated using a single degree of freedom system and a suite of 20 earthquake records. RMS noise of 5%, 10%, 15% and 20% is added to the response data to assess the robustness of the identification routine. The proposed method is computationally efficient and accurate in identifying the damage parameters within 10% average of the known values even with 20% added noise. The method requires no user input and could thus be automated and performed in real-time for each sub-half cycle, with results available effectively immediately after an event as well as during an event, if required.

• Geomechanics and Engineering
• /
• 제14권2호
• /
• pp.141-149
• /
• 2018

In this paper, the creep behavior of bolted rock was analyzed by using the unconfined creep tests and the numerical results. Based on the test results, the Bolted Burgers creep model (B-B model) was proposed to clarify the creep mechanism of rock mass due to rock bolts. As to the simulation of the creep behaviour of bolted rock, a new user-defined incremental iterative format of the B-B model was established and the open-source $FLAC^{3D}$ code was written by using the object-oriented language (C++). To check the reliability of the present B-B creep constitutive model program, a numerical model of a tunnel with buried depth of 1000 m was established to analyze the creep response of the tunnel with the B-B model support, the non-support and the bolt element support. The simulation results show that the present B-B model is consistent with the calculated results of the inherent bolt element in $FLAC^{3D}$, and the convergence deformation can be more effectively controlled when the proposed B-B model is used in the $FLAC^{3D}$ software. The big advantage of the present B-B creep model secondarily developed in the $FLAC^{3D}$ software is the high computational efficiency.

• 한국실내디자인학회논문집
• /
• 제17권3호
• /
• pp.15-22
• /
• 2008

The purpose of this study is to propose evaluation factors for elementary school facility in terms of educational adequacy. The focal point of this study is to clarify the proper measure of educational facility evaluation in the light of specific characteristics of facility. In order to improve the level of educational adequacy, more information is needed regarding school facility design and various factors which affect to the design. This is important works because such information is essential in implementing facility design to meet the needs of the new educational policy. To get the goal, first, it is attempted to analyse the meaning of design information which deeply affect on the school facility design. The design information is classified into three main aspects, such as human aspect, social aspect and physical aspect. The design information regarding the physical space verses human psychology and behavior belongs to category of human aspect. Pedagogic ideology which varies depend upon the time and regions is classified into the category of social aspect. The Physical aspect means efficient equipment performance of space to support educational activities effectively. Secondly, as for the educational adequacy evaluation concern, it is attempted to select more items which usually has been neglected by the existing evaluation criteria which mainly emphasized functional performances only. With the premise of the above, in this paper, it is attempted to propose proper evaluation factors in terms of educational adequacy for school facilities. As the research methods, researching of literature on this subject, field trip, interview, site analysis, and survey is used.

• 한국전자거래학회지
• /
• 제26권3호
• /
• pp.133-153
• /
• 2021

최근, 조직 내 중앙집중식 콘텐츠관리 체계 구축을 위한 기술적 투자가 많아지고 있다. 하지만, 높은 품질의 기술 도입은 역으로 구성원들의 기술 스트레스를 발생시켜 부정적 행동을 발생시킬 가능성이 있다. 본 연구의 목적은 기업콘텐츠관리시스템 관련 기술 스트레스의 지속적 이용 의도에 미치는 부정적 영향을 제시하고, 기술 스트레스 완화 방향을 제시하는 것이다. 본 연구는 콘텐츠관리 기술을 도입한 조직의 구성원에게 설문하였으며, 구조방정식모델링을 적용하여 가설 검증을 하였다. 분석 결과 기업콘텐츠관리시스템 관련 기술 과부하와 복잡성이 지속적 이용 의도를 감소시켰지만, 조직 내 사내 커뮤니케이션 활동이 기술 스트레스를 완화시켰으며, 개인의 업무-기술 적합성이 기술 스트레스와 지속적 이용 의도에 대한 조절 효과를 가지는 것을 확인하였다. 연구는 콘텐츠관리시스템의 이용에 있어 부정적 영향을 미치는 측면을 최소화하기 위한 조직 차원의 노력 요인을 제시한 측면에서 시사점을 가진다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권11호
• /
• pp.2920-2939
• /
• 2012

Enterprises that develop online games have to deploy supporting infrastructures, including hardware and bandwidth resources, in order to provide a good service to users. First Person Shooter games generate high rates of small UDP packets from the client to the server, so the overhead is significant. This work analyzes a method that saves bandwidth, by the addition of a local agent which queues packets, compresses headers and uses a tunnel to send a number of packets within a multiplexed packet. The behavior of the system has been studied, showing that significant bandwidth savings can be achieved. For certain titles, up to 38% of the bandwidth can be saved for IPv4. This percentage increases to 54% for IPv6, as this protocol has a bigger overhead. The cost of these bandwidth savings is the addition of a new delay, which has an upper bound that can be modified. So there is a tradeoff: the greater the added delays, the greater the bandwidth savings. Significant reductions in the amounts of packets per second generated can also be obtained. Tests have been deployed in an emulated scenario matching an access network, showing that if the number of players is big enough, the added delays can be acceptable in terms of user experience.

• 한국정보컨버전스학회:학술대회논문집
• /
• 한국정보컨버전스학회 2008년도 International conference on information convergence
• /
• pp.135-140
• /
• 2008

Recently in the Mongolian wireless marketplace, many E-commerce companies have been making considerable investments in the technological development of M-commerce, taking competitive advantage of new business possibilities offered by Internet-based wireless technologies. In the Mongolian wireless marketplace, this new mobile environment opens the door for new and exciting market opportunities in mobile services and applications. In the near future, these companies will be looking toward M-commerce services as a supplemental source of revenue in the mobile marketplace. This paper examines the roles of M-commerce in the consumers' in order to promote the consumers' loyalty in the booming M-commerce. This paper contains theory that focuses on the basic concepts of the M-commerce environment, its wireless network technologies, and its applications infrastructure. Upon searching for references to assist us in establishing a market hypothesis, we discovered that few comprehensive studies on consumer perspective and behavior related to M-commerce services actually exist in the literature. In the area of M-commerce, many companies neglect the consumer perspective, concentrating only on technological factors only when formulating their market strategies. And, due to technological blindness, many companies were not able to succeed in end-user E-commerce services. Given that fact, this paper formulates a consumer-centric research model. In order to prove the research model, we chose the survey method which allows for the collection of large amounts of data from a sizeable population in a highly economical way. Through the survey, this paper defines consumer's attitudes towards M-commerce services by identifying potential Business-to-Commerce(B2C) applications and its primary target groups in terms of gender and age, and by investigating whether consumers recognize the value proposition of M-commerce applications and services. As shown in the data analysis and results, this research concludes that M-commerce development in Mongolia is still at its infancy, and that the implementation of M-commerce depends not only on technological progress, but also on consumer attitudes and their willingness to adopt M-commerce services. As well, other complex cross-cultural factors-socially, economically, culturally, et cetera-enter strongly into the equation.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
• /
• 제29권3호
• /
• pp.17-28
• /
• 2023

Purpose: This study aims to provide basic data for the future construction plans of the Infectious Disease Hospitals by analyzing the area composition and required room ratios in the wards and ICU of currently under-construction infectious disease hospitals. Methods: 3 Methods have been used in this paper. 1) This study conducted a literature review on major considerations and related guidelines for hospitals specializing in infectious diseases using existing data. 2) Based on the objects and activities of the hospital space, zones and areas were set for each department according to infection control. 3) Based on the established zones and areas, basic plan drawings of three hospitals specializing in infectious diseases currently under construction were collected and architectural drawing analysis was performed. Results: 1) Infectious Diseases Hospital must have a spatial organization that can accommodate patient isolation, infection control, efficiency of medical service, and changes. 2) Zones for infection control are divided into negative pressure and non-negative pressure zones based on airborne precaution isolation. It is divided into clean and contaminated zone according to class of cleanliness by Aseptic technique. Areas are classified by objects (patients, healthcare workers, supplies) and activities (access, medical treatment, support), and a system for organizing space is established based on this. 3) By analyzing the area composition of each departmental area, each required room, and each required space in the wards and intensive care units, it provides basic data for the spatial organization for architectural planning of the infectious disease hospital. Implication: It can be used as basic data when planning related facilities by analyzing the characteristics of the space plan of the required room according to the relationship between activities, movement lines, and operation plans based on user behavior.

• 디자인융복합연구
• /
• 제15권2호
• /
• pp.223-236
• /
• 2016

근대화의 발전과 함께 성장해온 서울의 대중교통의 인프라는 국내외로 성공적인 평가를 받고 있으며 현재 가장 높은 수송 분담률을 가지고 있다. 그럼에도 불구하고 서비스 고도화 단계에 진입한 서울시의 대중교통은 아직도 부족한 부분이 많으며 특히 교통약자에 대한 이동성이 보장되지 않고 있다. 고령화 및 다문화 등의 사회적 변화에 맞춰 특정 계층의 대중교통 이용에 지원이 필요한 시점이다. 본 연구에서는 대중교통의 현황 및 이용자의 현황을 살펴보고 고령자 및 외국인을 주 조사 대상으로 선정하여 관찰조사를 진행하고 행태를 분석하였다. 또한 심층 인터뷰를 통해 대중교통 서비스 상세한 평가를 진행하여 대중교통수단과 이용단계 별 불편요소를 발굴하였다. 이를 토대로 아이디어 워크숍을 통해 개선요소를 정의하고 컨셉 디자인을 하여 향후 대중교통에 적용할 수 있는 개선안을 제시하여 추후 대중교통 서비스를 개선하는데 일조하고자 하였다.

• 터널과지하공간
• /
• 제16권1호
• /
• pp.1-10
• /
• 2006

실제 암반에는 단층, 절리, 층리, 균열, 단열, 편리, 벽개 등의 불연속면이 많이 포함되어 있다. 따라서, 불연속면이 암반구조물의 거동을 좌우하고 있다. 암반구조의 복잡성으로 인해 사전에 예측 할 수 없었던 암반의 붕락이 발생하여, 붕락대책에 막대한 비용과 시간을 낭비하는 사례가 많다. 암반 불연속면의 복잡성을 사전 조사단계에서 충분히 파악하거나 대책을 수립하는 것은 어렵다. 최근 터널의 정보화 설계시공이 중요시되어지고 있다. 본 논문에서는 불연속성 암반에서의 터널의 신 정보화 설계시공법을 제안하고, 현지에서 관찰한 불연속면 정보를 근거로 하여 실제 터널현장에 적용했다. 실제 터널현장에 있어서, 터널의 신 정보화 설계시공법을 위해서 새롭게 개발한 수치해석 프로그램을 사용하여 정확한 키블럭 추출이 가능하였다. 사용하기 쉬운 사용자 인터페이스를 가지고 있는 본 컴퓨터 시뮬레이션 기법은 암반블럭의 안정성 계산뿐만 아니라 추가 보강대책공의 설계도 가능하다. 터널 굴착중에 키블럭을 확인하므로써, 제안한 신 정보화 설계시공법의 유효성에 대한 검증을 하였다.

• 대한인간공학회지
• /
• 제34권2호
• /
• pp.191-198
• /
• 2015

Objective: As a cue for desired mood, we attempted to identify types of sitting postures when people are involved in various tasks during their working hours. Background: Physical behaviors in reaction to user contexts were studied, such as automated posture analysis for detecting a subject's emotion. Sitting postures have high feasibility and can be detected robustly with a sensing chair, especially when it comes to an office. Method: First, we attached seven sensors, including six pressure sensors and one distance sensor, to an office chair. In Part 1, we recorded participants' postures while they took part in four different tasks. From the seven sensors, we gathered five sets of data related to the head, the lumbar, the hip, thigh pressure and the distance between the backrest and the body. We classified them into four postures: leaning forward, upright, upright with the lumbar supporting, and leaning backward. In part 2, we requested the subjects to take suitable poses for the each of the four task types. In this way, we compared the matches between postures and tasks in a natural setting to those in a controlled situation. Results: We derived four types of sitting postures that were mapped onto the different tasks. The comparison yielded no statistical significance between Parts 1 and 2. In addition, there was a significant association between the task types and the posture types. Conclusion: The users' sitting postures were related to different types of tasks. This study demonstrates how human emotion can interact with lighting, as mediated through physical behavior. Application: We developed a posture-based lighting system that manipulates the quality of office lighting and is operated by changes in one's posture. Facilitated by this system, color temperatures ranging between 3,000K and 7,000K and illuminations ranging between 300lx and 700lx were modulated.