• 제목/요약/키워드: Engineering history

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A Brief History of Architectural Acoustics in China.: Yesterday and Tomorrow.

  • Yan, Xiang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.05a
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    • pp.461-461
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    • 2010
  • The history of architectural acoustics is a part of history of human being getting together for both politics and entertainments, is also a part of the history of nobility pursuing hearing enjoyments, is still a part history of scientists deeply understanding the concept of "just for people", and as well as is a part history ceaselessly driven by the musicians to find their real hearts through music. The history of architectural acoustics explains not only the acoustic knowledge developments in architectural design, but also the unity on contradictory of both the science and the arts, both the technology and the culture, both the sense and sense organ. The history of architectural acoustics prints the interactions between the mankind and the nature, between the mankind and themselves, between the mankind and their souls, in which course people understand their feelings more deeply and deeply. This paper discusses the brief history of architectural acoustic in China from the ancient drama stages to grand theaters in 20 century, even up to nowadays, including some most important buildings and events as well.

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Cognitive Based Context Aware Reference History Management Tool

  • Punithan, Dharani;McKay, Bob
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.227-231
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    • 2009
  • The aim of the research is to focus on the cognitive principles and to achieve human-level intelligence in referring context based browser history and the Windows history. One of the major problems faced by today's computer users is insufficient and single exclusive context based reference of the browser history and the Windows history. Today we search for the browser history and Windows history in different places even though the context is the same. For e.g., When working on a research paper or preparing a business presentation, a user may require to refer many web sites on the internet and various documents on the local computer. The browser can provide only time based history. The windows document history is also time based and limited to list only few documents. Hence, we propose a tool "Cognitive Based Context Aware Reference History Management Tool" which helps to access the exclusive reference of context and time based history in one place. The tool also proposes to store image history with urls and classifies images of a specific topic accessed in different time, bookmarks management and cross browser history management. These features are very useful as we can access all related documents (doc, docx, ppt, pptx, pdf, txt, and html), web pages, images and bookmarks in one place. The tool uses the cognitive principles like classification and association to achieve the purpose.

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History of Offshore Engineering Development

  • Choi, Han-Suk
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.249-252
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    • 2006
  • This paper introduces a review and literature study of offshore engineering and constructions from 1920s to 2000s. The study was focused on the literature survey and the history of Brown & Root and J. Ray McDermott in the Gulf of Mexico and other offshore areas Understanding the offshore history and background of offshore development is an essential ingredient for the initial conceptual design. This study was motivated to enhance the capacity of conceptual design and Front End Engineering Design (FEED) of offshore structures in Korea.

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An Analysis of Location Management Cost by Predictive Location Update Policy in Mobile Cellular Networks (이동통신망에서 예측 위치 등록 정책을 통한 위치관리 비용 감소 효과 분석)

  • Ko, Han-Seong;Hong, Jung-Sik;Chang, In-Kap;Lie, Chang-Hoon
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.2
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    • pp.160-171
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    • 2008
  • MU's mobility patterns can be found from a movement history data. The prediction accuracy and model complexity depend on the degree of application of history data. The more data we use, the more accurate the prediction is. As a result, the location management cost is reduced, but complexity of the model increases. In this paper, we classify MU's mobility patterns into four types. For each type, we find the respective optimal number of application of history data, and predictive location area by using the simulation. The optimal numbers of four types are shown to be different. When we use more than three application of history data, the simulation time and data storage are shown to increase very steeply.

Effects of Previous History on Diffusivity and Solubility of Gas in the Polymer Matrix (이력이 고분자 재료 안으로의 확산 및 용해에 미치는 영향)

  • 윤재동;차성운;최광용;조현종
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.3
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    • pp.108-113
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    • 2000
  • An important process for making a new class of polymeric material is called microcellular plastics invented at the Massachusetts Institute of Technology. Many researches for microcellular plastics have been done in various ways and fields. But a research for the polymer which has previous history has not been tried yet. In this paper, weight gain of $CO_2$ was measured in a polymer matrix which had previous history and no history. In each case, experimental data for solubility and diffusivity was shown. A model for $CO_2$ solution process in molecular range was made. The conclusion of this paper is that the previous history has an effect on diffusivity but not solubility and the previous history made by $CO_2$ in supercritical state makes diffusivity of $CO_2$ larger.

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Damage monitoring scheme of beam-type structures using time history of natural frequencies (고유진동수의 시간이력을 이용한 보 구조물 손상 모니터링 기법)

  • 박재형;김정태;류연선
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.04a
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    • pp.41-47
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    • 2004
  • The objective of this paper is to monitor damage in beam-type structures by using time history of natural frequencies. First, numerical experiments on test beams are described, Dynamic responses of the test structures are obtained for several damage scenarios in a consequent order. Next, the time history of natural frequencies are extracted for the first four modes from the dynamic responses of the test structures. Finally, damage detection in the test structures is performed using the time-history of natural frequencies.

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KHistory: A System for Automatic Generation of Multiple Choice Questions on the History of Korea (KHistory: 한국사 객관식 문제 자동 생성 시스템)

  • Kim, Seong-Won;Jung, Hae-Seong;Jin, Jae-Hwan;Lee, Myung-Joon
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.1
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    • pp.253-263
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    • 2017
  • As needs for knowledge on Korean history and the attention of the people are rapidly increasing, various smartphone applications for learning the history have appeared during recent years. These applications provide multiple choice questions to users through their own problem banks. But, since these questions are selected from the fixed set of problems that are stored previously, the learning efficiency of users is inevitably decreased when they use the applications repeatedly. In this paper, we present a question generation system named K-History which generates multiple choice questions in an automatic way using the database on the history of Korea. In addition, we also describe the development of the application Korean History Infinite Challenge as a learning application for Korean history. To develop K-History, we classify typical types of learning problems through various problems based on Korean history learning materials, proposing algorithms to generate problems according to the types found. Through the developed techniques, various learning systems can reduce the cost for creating questions, while increasing the learning efficiency of users.

An Enhanced Algorithm for the Generation of Artificial Acceleration Time History (인공 가속도 시간이력 작성을 위한 개선된 알고리즘)

  • 김종수
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1998.10a
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    • pp.304-311
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    • 1998
  • An algorithm to enhance spectra matching of acceleration time history used in the seismic analysis of nuclear power plants(NPP) is proposed. The new scheme provides the solution on the highly fluctuating and over conservatism problems that happened in order to satisfy design spectrum enveloping criteria in the traditional method. To obtain optimized spectrum for a time history, a spectrum matching procedure that adapts a system identification technique is also developed. The algorithm also introduces maximum displacement control, baseline correction, clipping and raising of maximum peak of time history, and power spectral density (PSD) control of time history. It is verified through numerical examples that this new scheme can definitely generate acceleration time history, closely matching the target spectra and satisfying other stipulated requirements.

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Effect of Stress History on CPT-DMT Correlations in Granular Soil (응력이력이 사질토의 CPT-DMT 상관관계에 미치는 영향)

  • Lee, Moon-Joo;Choi, Sung-Kun;Kim, Min-Tae;Lee, Ju-Hyeong;Lee, Woo-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.730-739
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    • 2010
  • Stress history increases in penetration resistance due to the increase in residual horizontal stress of granular soil. This study analyzes the effect of stress history on the results of CPT and DMT from calibration chamber specimen in OC as well as NC state. Test results show that the normalized cone resistance by mean effective stress correlates well with the relative density and the state parameter, whereas the normalized cone resistance with regard to vertical effective stress is a little affected by stress history. The horizontal stress index($K_D$) in DMT more reflects the influence of stress history on granular soil than the dilatometer modulus($E_D$) and cone resistance($q_c$). The $K_D/K_0$, in which the effect of stress history on $K_D$ is compensated by the at-rest coefficient of earth pressure, $K_0$, is related to relative density, state parameter and the normalized cone resistance by mean effective stress. It is also observed that the normalized dilatometer modulus by mean effective stress($E_D/{\sigma_m}'$) is unique correlated with the state parameter, regardless of stress history.

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