• Title/Summary/Keyword: u-turn

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The Measurement of Social Carrying Capacity on the Total Amount of Vehicles for Estimation of the Appropriate Number of Vehicles in U-do Island (적정입도차량대수 산정을 위한 자동차 총량제에 대한 사회적 수용력 측정)

  • Hwang, Kyung Soo;Ko, Tae Ho;Lim, Jung Hyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5D
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    • pp.605-610
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    • 2009
  • The either satisfaction levels or limits of tolerance levels felt by the users in the certain space/region should be examined for measuring social capacity on the total amount of vehicles. The reliability of measuring social carrying capacity depends primarily on decreasing the strategic responding biases. To induce the honest responses to preferences, Dichotomous Choice which is specifically known as the Double-Bounded Dichotomous Choice was adopted in this research to suggest the measurement methodology of social carrying capacity on the total amount of vehicles in U-do island. The empirical test was carried out the U-do island, an administrative district of Jeju Special Self-Governing Province. The number of vehicles satisfied by the 10% of residents was 390 and the satisfactory vehicle number was decreased to 132 extended to 90% of residents. This research, based on the political decision making criteria, set up the social carrying capacity in U-do island. The vehicle number satisfied by 50% of residents was 227, which meant the same number of residents turn to be supporter in case of political actions.

A Study on Quality Assurance for Rotational Molding Products (회전성형 제품의 품질 개선을 위한 연구)

  • Lee, Jung-Ki;Han, Hui-Duck;Kim, Hyun-Joo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.6
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    • pp.826-837
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    • 2004
  • Rotational molding is a plastics processing technique that is ideally suited to producing relatively large, hollow, seamless parts which are partially or totally enclosed. Designers of plastic parts turn to rotational molding to produce small or large parts of unusual shape that cannot be produced as one piece by other processes, e.g., blow molding and thermoforming. In this paper, in order to enhance the quality of rotational molding plastic products, 1) surface features for the plastic products are characterized by using an image analysis system, 2) maximum tensile strength for the plastic products that are made of materials that consist of Samsung-Atofina R90lU, pigments and two different kinds of calcium carbonate (OMYA CaCO$_3$) is measured and compared with each other by using an Instron universal testing machine, 3) thickness for the plastic products is non-destructively measured to investigate the quality of the plastic products by using an A-scan ultrasonic tester.

Simulation-Based Determination of Hydrodynamic Derivatives and 6DOF Motion Analysis for Underwater Vehicle (시뮬레이션 기반 수중 운동체의 유체력 미계수 결정 및 6자유도 운동해석)

  • Go, Gwangsoo;Ahn, Hyung Taek;Ahn, Jin-Hyeong
    • Journal of Ocean Engineering and Technology
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    • v.31 no.5
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    • pp.371-377
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    • 2017
  • This paper introduces a simulation-based determination method for hydrodynamic derivatives and 6DOF (degrees-offreedom) motion analysis for an underwater vehicle. Hydrodynamic derivatives were derived from second-order modulus expansion and composed of the added mass, and linear and nonlinear damping coefficients. The added mass coefficients were analytically obtained using the potential theory. All of the linear and nonlinear damping coefficients were determined using CFD simulation, which were performed for various cases based on the actual operating condition. Then, the linear and nonlinear damping coefficients were determined by fitting the CFD results, which referred to 6DOF forces and moments acting on an underwater vehicle, with the least square method. To demonstrate the applicability of the current study, 6DOF simulations for three different scenarios (L-, U-, and S-turn) were carried out, and the results were validated on the basis of physical plausibility.

Review of Environmental Education in the US National Parks Service according to Social Transition : A Case Study on Two Pacific Northwest National Parks

  • Myers, Gene;Park, Chung-In
    • Journal of Environmental Science International
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    • v.22 no.4
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    • pp.385-396
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    • 2013
  • National park, as a natural park, has a dual purpose, to promote both protection and enjoyment. The educational activities of the national park can be partly understood as one of the appropriate means to balance its double purposes. This study provides a review of environmental education in the US National Parks according to social transition. Taking historical perspective and case studies, environmental education has played roles in helping the balance between preservation and enjoyment. Since the environmental movement, environmental education goals, particularly understanding the natural processes observable at national parks, has become more a part of the interpretation and education missions of the parks. Also non-governmental and non-profit partners have played important educational-based roles in support of both the National Parks Service and environmental education goals. The two different models also differ in the public's perception of them. Federal employees are resented in some rural areas in the U.S., but the general population automatically attributes authority, friendliness, and national-interestedness to NPS Rangers. This may in turn limit how strongly such staff could serve as strong advocates for the environment. On the other hand, the non-profit may be seen by some as strongly liberally biased and associated with urban wealth. It is also not as universally recognized as the NPS. It can, however, go far to develop new partnerships and undertake public relations. Non-profits vary greatly in quality, also affecting public perception.

SK텔레콤의 성공적인 다운사이징 사례;U.Key의 탄생

  • Jang, Si-Yeong;Lee, Sang-Gu
    • 한국경영정보학회:학술대회논문집
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    • 2007.11a
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    • pp.309-315
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    • 2007
  • SK텔레콤은 급변하는 이동통신시장 환경의 변화에 적절히 대응하기 위하여 지난 10여 년간 사용해 온 메인프레임 기반의 COIS 시스템을 중단하고 Unix 기반의 NGM 시스템으로 다운사이징하기로 결정하였다. 2002 년 9 월 SK 텔레콤은 차세대 IT 인프라 혁신 전략 프로젝트를 완료하고 이에 근거하여 2003 년 말 1 단계 프로젝트를 추진하게 된다. 그러나 개발 툴의 문제점, Governance 의 확보 실패 등 문제점이 계속 누적되어 2005년에 접어들어서는 총체적 난국 상황에 봉착하게 되었다. 2005 년 2 월 자체 점검 결과 개발 진척도는 50%에 불과한 상황이었다. 결국 2005 년 3 월, NGM 추진본부는 프로젝트의 추진 중단을 선언하기에 이르렀다. NGM 프로젝트는 처음부터 재 검토하여 Re-planning 을 실시한 후 구축을 재개하기로 결정하였다. 2005 년 5 월 NGM 프로젝트의 Re-plan 이 수립되었다. 우선 Turn-key 방식의 문제점을 해소하기 위하여 SK 텔레콤이 구축의 총책임을 떠맡고, SK C&C 가 시스템 이행에 대한 책임을 지는 Governance 체제를 확립하였다. 또한 2 단계 프로젝트에서는 NGM 프로젝트를 기술적으로 원점부터 재 검토하여 이전과는 근본적으로 다른 In-House 구축 접근방식을 채택하기로 하였다. 2 단계 프로젝트에서 관심을 집중한 기술적 의사결정 영역은 크게 (1) 미들웨어 및 개발프레임워크의 적용, (2) DB 아키텍처의 결정 및 슬림화, (3) 시스템 성능 개선 등의 세 분야로 집약할 수 있다. 이 논문에서는 이들 각각의 분야를 구체적으로 검토하였다. 결국 2006 년 10 월 9 일 메인프레임 기반의 COIS 는 Shut-down 되어 가동을 멈추었고, Unix 기반의 NGM 시스템이 가동을 개시함으로써 차세대 마케팅을 본격 추진하기 위한 다운사이징 프로젝트가 성공적으로 완수되었다.

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A Study on the Design of Major Living Spaces and Facilities for the Aged($^{\circ}$)-Toward Basic Conceptualization- (실버타운의 주요 생활공간과 시설물의 디자인에 관한 연구(I)-기본개념의 정립을 중심으로-)

  • 오인완;이인수
    • Korean Institute of Interior Design Journal
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    • no.12
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    • pp.25-32
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    • 1997
  • The fast growth of the elderly population and nuclear families have been creating substantial needs for residential facilities of aged people in Korea. In this study, reviews on housing preference and physical constraints have been performed based on previous researches. In this study, the results of the analyses propose developmental strategies for the elderly housing in Korea as follows: 1)Housing preference and other psychological trends of Korean elderly are rooted in changeable condition of the emotion and lack of knowledge. Therefore, the housing preference of the Korean elderly should not be considered a fixed reflection ; rather, it should be regarded as a continuously adjusted trends according to later experience and emotional status after residing in the elderly care facilities. 2)Design of elderly housing should be guided within two principles of easy access and high usability. The principles also require maximazation of social interactions among frail elderly residents on age-segregated structure. 3) The experiment among 201 frail elderly shows that each shower stall should accommodate 5-by-5 feet square for wheelchair u-turn, and 48 inch height for kitchen topsink. Finally, the experiment shows that ramp slope of the ederly housing should be within 1/16 and 1/20.

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An Experimental Study on In-Plate Evaporation Heat Transfer and Flow Characteristics for Automobile (자동차용 증발기 판 내의 증발 열전달 및 유동 특성에 관한 실험적 연구)

  • Kwak, Kyung-Min;Joo, Sang-Woo;Jung, Woo-Youl;Kim, Taek-Keun;Kim, Kwang-Il
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.2
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    • pp.95-100
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    • 2007
  • An experimental study was performed to evaluate the in-plate evaporation heat transfer and flow characteristics of a evaporator used in automobile. Two test-cores with different heat transfer area, bead-shape and bead-array were tested, A type and B type. For the heat transfer, Nusselt number for B type test-core reaches a value nearly equal to the one for A type test-core, in the whole range of equivalent Reynolds number. But, for the same mass flow rate of refrigerant, hA for B type test-core becomes higher with the increase of the mass quality of refrigerant than for A type test-core. In a flow visualization experiment, the wake zone of refrigerant circulating at u-turn position of plate is observed.

Investigation of the effect of weak-story on earthquake behavior and rough construction costs of RC buildings

  • Gursoy, Senol;Oz, Ramazan;Bas, Selcuk
    • Computers and Concrete
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    • v.16 no.1
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    • pp.141-161
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    • 2015
  • A significant portion of residential areas of Turkey is located in active earthquake zones. In Turkey occurred major earthquakes in last twenty years, such as Erzincan (1992), Kocaeli and $D{\ddot{u}}zce$ (1999), $Bing{\ddot{o}}l$ (2003), Van (2011). These earthquakes have demonstrated that reinforced concrete (RC) buildings having horizontal and vertical irregularities are significantly damaged, which in turn most of them are collapsed. Architectural design and arrangement of load-bearing system have important effect on RC building since architectural design criteria in design process provide opportunity to make this type of buildings safer and economical under earthquake loads. This study aims to investigate comparatively the effects of weak story irregularity on earthquake behavior and rough construction costs of RC buildings by considering different soil-conditions given in the Turkish Earthquake Code. With this aim, Sta4-CAD program based on matrix displacement method is utilized. Considering that different story height and compressive strength of concrete, and infill walls or their locations are the variables, a set of structural models are developed to determine the effect of them on earthquake behavior and rough construction costs of RC buildings. In conclusion, some recommendations and results related to making RC buildings safer and more economical are presented by comparing results obtained from structural analyses.

Statistical division of compressive strength results on the aspect of concrete family concept

  • Jasiczak, Jozef;Kanoniczak, Marcin;Smaga, Lukasz
    • Computers and Concrete
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    • v.14 no.2
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    • pp.145-161
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    • 2014
  • The article presents the statistical method of grouping the results of the compressive strength of concrete in continuous production. It describes the method of dividing the series of compressive strength results into batches of statistically stable strength parameters at specific time intervals, based on the standardized concept of "concrete family". The article presents the examples of calculations made for two series of concrete strength results, from which sets of decreased strength parameters were separated. When assessing the quality of concrete elements and concrete road surfaces, the principal issue is the control of the compressive strength parameters of concrete. Large quantities of concrete mix manufactured in a continuous way should be subject to continuous control. Standardized approach to assessing the concrete strength proves to be insufficient because it does not allow for the detection of subsets of the decreased strength results, which in turn makes it impossible to make adjustments to the concrete manufacturing process and to identify particular product or area on site with decreased concrete strength. In this article two independent methods of grouping the test results of concrete with statistically stable strength parameters were proposed, involving verification of statistical hypothesis based on statistical tests: Student's t-test and Mann - Whitney - U test.

Performance improvement of PV_system's inverter that use transformer tap (변압기 탭을 이용한 태양광인버터의 성능개선)

  • Park Noh-Sik;Park Sung-Jun;Kim Kwang-Heon;Lim Young-Cheol;Kwon Soon-Jae;Kim Cheul-U
    • Proceedings of the KIPE Conference
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    • 2004.07b
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    • pp.511-514
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    • 2004
  • Proposed about new inverter that can use in PV system in this paper. Multi_level inverter that used inverter makes use of 4 transformers is basis, primary winding of each transformer voltage as can do step_up or step_down to appropriate voltage space tap lake. Put circuit that tap that turn in transformer connects properly according to inhibit signal that sense change of input voltage (output voltage of solar cell place) and transformer secondary voltage controls point of contact of relay so that get into fixed output voltage. As a result, can minimise relative harmonic content despite change width of input voltage are wide because number of output voltage level of multi_level inverter does not decrease. Because proposed circuit manufactures is easy and control is easy and is no burden of cost price rise economically, commercialization expected to do easily and this study examined propriety of action as that compose and experiments proposed circuit.

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