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Analysis of Post-LOCA pH for Korea Nuclear Units (국내 원자력발전소의 LOCA사고에 따른 pH 분석)

  • Hyung Won Lee;Yung Hee Kang;Jae Hee Kim
    • Nuclear Engineering and Technology
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    • v.15 no.3
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    • pp.179-187
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    • 1983
  • The pH of containment spray and sump water following a LOCA for KNU 5'||'&'||'6 and KNU 1 was calculated to see if pH design criteria of containment spray system established by USNRC were met. The pH calculations have been made for the two cases; maximum pH and minimum pH. For KNU 5'||'&'||'6, results showed that long term sump pH values calculated for the maximum pH and minimum pH case well met the pH requirement of at least 8.5 and spray pH for the maximum case slightly exceeded the range of design criteria (8.5 to 11.0). For KNU 1, pH requirement of long term sump pH was also met, however, spray pH value for the maximum pH case was very largely greater than that of current pH requirement. (No pH requirement of containment spray water has been established at the time of designing KNU 1) In order to find the design parameters of containment spray system which are expected to meet the spray pH requirement, several calculations were wade, by changing the input parameters to "LCCAPH". Finally, it was shown that the boric acid concentration in RWST (refueling water storage tank), which was the primary sources of containment spray water during injection mode, be maintained the range of 2750 ppm to 2850 ppm, or tile flow rate of NaOH added to spray water he kept between 10 gpm to 24 gpm.

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The Correlations among the Categorized Quality Cost Factors on SMEs (Small & Medium-sized Enterprises) (중소 제조기업의 품질비용 행태에 관한 실증 연구)

  • Lee, Sang-Choon;Koo, Il-Seob
    • Proceedings of the Safety Management and Science Conference
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    • 2011.04a
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    • pp.731-746
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    • 2011
  • The successful and sustainable growth of SMEs depends on their ability of strengthen their competitiveness in quality and cost and service more than anything else as a fundamental of operation. Among these key competitive factors of SMEs, quality is the most critical factor in manufacturing business fields. Because quality strongly influence cost and service performance on this manufacturing business field. There are many different ways to improve the quality performance but it needs proper management decision to choose the best way what can maximize outputs with minimum inputs. And it needs effective measurement methods and some indicators to analysis the quality performance properly. The quality cost is one of the simplest key indicators to measure the quality performance and the effectiveness of quality related management decisions. The major purpose of this study is to diagnose the categorized current level of actual quality cost of local SMEs to maximize their quality management effectiveness through comparing their level with others what's expressed in early studies. In this study, through survey on local SMEs, we found that their average annual quality cost ratio versus turnover - Total amount of annual quality cost divided by annual turnover - is around 3.69% excluded some SME's performances what have different quality control measures with others. And we found some results what corresponded with the early studies on the correlations between those categorized quality costs factors and some discrepancies between some of the literature model and the early case study results as follows. There were negative correlations between the Prevention costs and the External failure costs, and the Appraisal costs and the External failure costs, and there was positive correlation between the Appraisal costs and Internal failure costs same as early studies. But, we couldn't found any strong negative correlations between the Cost of control - Preventive costs & Appraisal costs - and the Cost of Failure of control - Internal & External failure costs -. It reveals not only the lack of effectiveness on their preventive or appraisal activities but also it can reveal there were so many effective ways to prevent the failure costs properly such as some innovative investment on Factory automation includes Error Proofing and more preventive actions to improve the effectiveness of the typical management methods likes CE (Concurrent Engineering), APQP (Advanced Product Quality Planning), FMEA (Failure Mode & Effect Analysis) etc.

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Extragalactic Sciences from SPICA/FPC-S

  • Jeong, Woong-Seob;Matsumoto, Toshio;Im, Myungshin;Lee, Hyung Mok;Lee, Jeong-Eun;Tsumura, Kohji;Tanaka, Masayuki;Shimonishi, Takashi;Lee, Dae-Hee;Pyo, Jeonghyun;Park, Sung-Joon;Moon, Bongkon;Park, Kwijong;Park, Youngsik;Han, Wonyong;Nam, Ukwon
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.36.2-36.2
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    • 2013
  • The SPICA (SPace Infrared Telescope for Cosmology & Astrophysics) project is a next-generation infrared space telescope optimized for mid- and far-infrared observation with a cryogenically cooled 3m-class telescope. The focal plane instruments onboard SPICA will enable us to resolve many astronomical key issues from the formation and evolution of galaxies to the planetary formation. The FPC-S (Focal Plane Camera - Sciecne) is a near-infrared instrument proposed by Korea as an international collaboration. Owing to the capability of both low-resolution imaging spectroscopy and wide-band imaging with a field of view of $5^{\prime}{\times}5^{\prime}$, it has large throughput as well as high sensitivity for diffuse light compared with JWST. In order to strengthen advantages of the FPC-S, we propose the studies of probing population III stars by the measurement of cosmic near-infrared background radiation and the star formation history at high redshift by the discoveries of active star-forming galaxies. In addition to the major scientific targets, to survey large area opens a new parameter space to investigate the deep Universe. The good survey capability in the parallel imaging mode allows us to study the rare, bright objects such as quasars, bright star-forming galaxies in the early Universe as a way to understand the formation of the first objects in the Universe, and ultra-cool brown dwarfs. Observations in the warm mission will give us a unique chance to detect high-z supernovae, ices in young stellar objects (YSOs) even with low mass, the $3.3{\mu}$ feature of shocked circumstance in supernova remnants. Here, we report the current status of SPICA/FPC project and its extragalactic sciences.

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Comparison of an Analytic Solution of Wind-driven Current and all (x-$\sigma$) Numerical Model (취송류의 해석위와 (x-$\sigma$) 수치모형과의 비교)

  • 이종찬;최병호
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.4 no.4
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    • pp.208-218
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    • 1992
  • Analytic solutions for the gradient of surface elevation and vertical profiles of velocity driven by the wind stress in the one-dimensional rectangular basin were obtained under the assumption of steady-state. The approach treats the bottom frictional stress $\tau$$_{b}$ as known and includes vertically varying eddy viscosity $textsc{k}$$_{M}$, which is constant, linear and quadratic of water depth. When the $\tau$$_{b}$ is param-terized with surface stress, depth averaged velocity and bottom velocity, the result shows the relation of the no-slip bottom velocity condition and the bottom frictional stress $\tau$$_{b}$. The results of a mode splitted, (x-$\sigma$) coordinate, numerical model were compared with the derived analytic solutions. The comparison was made for the case such that $textsc{k}$$_{M}$ is the constant, linear and quadratic function of water depth. In the case of constant $textsc{k}$$_{M}$, the gradient of surface elevation and vertical profiles of velocity are discussed for a uniform depth, a mild slope and a relatively steep slope. When $textsc{k}$$_{M}$ is a linear and quadratic function of water depth, the vertical structures of velocities are discussed for various $\tau$$_{b}$. The result of the comparison shows that the vertical structure of velocities depends not only on the value of $textsc{k}$$_{M}$ but also on the profile of $textsc{k}$$_{M}$ and bottom stress $\tau$$_{b}$. Model results were in a good agreement with the analytic solutions considered in this study.his study.y.his study.

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Effect of loading velocity on the seismic behavior of RC joints

  • Wang, Licheng;Fan, Guoxi;Song, Yupu
    • Earthquakes and Structures
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    • v.8 no.3
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    • pp.665-679
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    • 2015
  • The strain rate of reinforced concrete (RC) structures stimulated by earthquake action has been generally recognized as in the range from $10^{-4}/s$ to $10^{-1}/s$. Because both concrete and steel reinforcement are rate-sensitive materials, the RC beam-column joints are bound to behave differently under different strain rates. This paper describes an investigation of seismic behavior of RC beam-column joints which are subjected to large cyclic displacements on the beam ends with three loading velocities, i.e., 0.4 mm/s, 4 mm/s and 40 mm/s respectively. The levels of strain rate on the joint core region are correspondingly estimated to be $10^{-5}/s$, $10^{-4}/s$, and $10^{-2}/s$. It is aimed to better understand the effect of strain rates on seismic behavior of beam-column joints, such as the carrying capacity and failure modes as well as the energy dissipation. From the experiments, it is observed that with the increase of loading velocity or strain rate, damage in the joint core region decreases but damage in the plastic hinge regions of adjacent beams increases. The energy absorbed in the hysteresis loops under higher loading velocity is larger than that under quasi-static loading. It is also found that the yielding load of the joint is almost independent of the loading velocity, and there is a marginal increase of the ultimate carrying capacity when the loading velocity is increased for the ranges studied in this work. However, under higher loading velocity the residual carrying capacity after peak load drops more rapidly. Additionally, the axial compression ratio has little effect on the shear carrying capacity of the beam-column joints, but with the increase of loading velocity, the crack width of concrete in the joint zone becomes narrower. The shear carrying capacity of the joint at higher loading velocity is higher than that calculated with the quasi-static method proposed by the design code. When the dynamic strengths of materials, i.e., concrete and reinforcement, are directly substituted into the design model of current code, it tends to be insufficiently safe.

IEEE 802.11-based Power-aware Location Tracking System (저전력을 고려한 IEEE 802.11 기반 위치 추적 시스템)

  • Son, Sang-Hyun;Baik, Jong-Chan;Baek, Yun-Ju
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.7B
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    • pp.578-585
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    • 2012
  • Location tracking system through GPS and Wi-Fi is available at no additional cost in an environment of IEEE 802.11-based wireless network. It is useful for many applications in outdoor environment. However, a previous systems used for general device to tag. It is unsuitable for power aware location tracking system because general devices is more expensive and non-optimized for tracking. The hand-off method of IEEE 802.11 standard is not enough considering power consumption. This thesis analyzes the previous location tracking systems and proposes power aware system. First, we designed and implemented tag to optimize location tracking. Next, we propose low-power hand-off method and low-power behavior model in implemented tag. The proposed hand-off method resolve power problem by using the location information and behavior model minimize power consumption of tag through power-saving mode and the concept of duty cycle. To evaluating proposed methods and system performance, we perform simulations and experiments in real environment. And then, we calculate tag's power consumption based on the actual measured current consumption of each operation. In a simulation result, the proposed behavior model and hand-off method reduced about 98%, 59% than the standard's hand-off and default behavior model.

Operation Model Design of Logistics Industrial estate -Focused on Transportation Network- (물류산업단지의 운영모델 설계 - 운송 네트워크를 중심으로-)

  • Shin, Jae Young;Kim, Woong-Sub
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.06a
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    • pp.214-215
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    • 2013
  • Current competition among companies than regional, the time constraints, it is globalization, Tilt the efforts of many to be operated by building the efficient distribution system to reduce logistics costs and improve customer service it is reality's there. Therefore, the need for industrial complexes environmentally friendly can be cost competitive companies perform cavitation region's increased. To build the distribution center these logistics system through a joint of freight and appropriate policy is required. In particular, efficient operation through the system construction of industrial complexes in the logistics system is very important in terms of friendly low-cost urban logistics, the environment. Since the traffic volume which is Jipufa and utilization of network is transported by a more appropriate technicians and means suitable operating model can efficiency is improved. However, despite these advantages, research network design has not been actively conducted due to the complexity of the problem. Therefore, in this study, by analyzing the logistics system, and presents the operating model through a simulation and basic settings for the model of the logistics complex based on the analysis result, the construction of infrastructure of logistics industry complex it is intended to present the article.

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A Study on Formative Elements in 3D Animation Character -Focusing on Characters' Visual Recognition Elements of Form through Elements of Form and Formation Method of Form- (3D 애니메이션 캐릭터의 조형성 연구 -<겨울왕국> 캐릭터를 중심으로 조형의 구성요소와 원리를 통한 시각인지요소에 관한 연구-)

  • Kim, Hye Sung;Sung, Re-A
    • Cartoon and Animation Studies
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    • s.36
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    • pp.45-74
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    • 2014
  • We can anticipate that animations will form one of the axes and lead popular culture in our future visual age. Recently, research has been actively conducted, but it mainly focuses on their value in culture industry or technologies and methods of producing animations. Of course, research that deals with animation characters has constantly come out. This study focuses on the 'formative elements' of 3D animation characters and attempts differentiation from other research by inducing new logic theoretically. Being freed from the research on characters that has been merely focused on theoretical grounds, this study intends to figure out how audience that is consumers who actually get to watch and feel animations recognizes them and find out related problems and also solutions for them. In particular, this study intends to examine the formative characteristics of 3D animation characters with the characters appearing in , one of the animations that have achieved artistic value as well as commercial success. And for that, the study conducted not only literature review but various surveys and Delphi method as well. Also, the researcher devised an analysis frame to evaluate the formative elements through in-depth discussion with experts. And with this, the study created the forms such as the Elements of Form, Formation Methods of Form and Visual Recognition Elements of Form, examined how audience recognized 3D characters. The process of recognizing an image is influenced by socio-cultural environment or sex, age, and the level of knowledge differently. This was meant to investigate current visual culture and the public's perspective through characters in that represent the visual mode.

Transport Demand Management in Developing Countries and Climate Change (개발도상국의 교통수요관리와 기후변화)

  • Lee, Shin
    • Journal of the Society of Disaster Information
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    • v.14 no.3
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    • pp.288-295
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    • 2018
  • Purpose: The paper aims to compare the effectiveness of the two types of transport demand management measures, namely pull measures and push measures. Method: Case studies of two metropolitan areas in the developing world assess the extent to which increases in fuel prices can contribute to reducing automobile use and increasing the public transport use and the potential of urban rail transit to cause mode shift from automobiles. Within the case studies, a stated response survey of current car users has been conducted for Cairo and an on-line survey of rail transit users in Algiers. Results: There was a major proportion of car drivers who intend to switch to public transport, depending on the range of fuel prices in Cairo and a considerable proportion of rail users who have switched from automobiles resulting in a measurable reduction in CO2 emissions in Algiers. Conclusion: Investments in urban rail can be highly effective where there are demands for better public transport, but this type of pull measures can be much more effective if combined with push measures which significantly raise driving costs.

Nano-scale Patterning on Diamond substrates using an FIB (FIB를 이용한 다이아몬드 기판 위의 나노급 미세 패턴의 형상 가공)

  • Song, Oh-Sung;Kim, Jong-Ryul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.6
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    • pp.1047-1055
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    • 2006
  • We patterned nano-width lines on a super hard bulk diamond substrate by varying the ion beam current and ion beam sources with a dual beam field ion beam (FIB). In addition, we successfully fabricated two-dimensional nano patterns and three-dimensional nano plate modules. We prepared nano lines on a diamond and a silicon substrate at the beam condition of 30 kV, 10 pA $\sim$ 5 nA with $Ga^+$ ion and $H_2O$ assisted ion sources. We measured each of the line-width, line-depth, etched line profiles, etch rate, and aspect ratio, and then compared them. We confirmed that nano patterning was possible on both a bulk diamond and a silicon substrate. The etch rate of $H_2O$ source can be enhanced about two times than that of Ga source. The width of patterns on a diamond was smaller than that on a silicon substrate at the same ion beam power The sub-100 nm patterns on a diamond were made under the charge neutralization mode to prevent charge accumulation. We successfully made a two-dimensional, 240 nm-width text of the 300-lettered Lord's Prayer on a gem diamond with 30 kV-30 pA FIB. The patterned text image was readable with a scanning electron microscope. Moreover, three dimensional nano-thick plate module fabrication was made successfully with an FIB and a platinum deposition, and electron energy loss spectrum (EELS) analysis was easily performed with the prepared nano plate module.

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