• Title/Summary/Keyword: Basic Concept

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High Value-added Technology of Oil Sand (오일샌드 고부가화기술 동향)

  • Park, Yong-Ki;Choi, Won Choon;Jeong, Soon Yong;Lee, Chul Wee
    • Korean Chemical Engineering Research
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    • v.45 no.2
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    • pp.109-116
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    • 2007
  • As conventional light oil resources deplete, it is becoming necessary to develop unconventional resources. To meet the demand for petrochemical industry, heavier sources such as heavy oil and bitumen are being utilized. Bitumens, a complex hydrocarbon made up of a long chain of molecules, are found in oil sand. It is estimated that 830 billion barrels of oil are located in the oil sand in Alberta, Canada. This paper will review briefly (1) the basic concept of oil sand, bitumen, and heavy oil, (2) methods how to extract oil from oil sand, (3) methods how to upgrade to synthetic crude oil, and (4) economic evaluation of technology.

Regionalization of neonatal care and neonatal transport system (신생아 괸리의 지역화 및 전원시스템)

  • Sin, Jong Beom
    • Clinical and Experimental Pediatrics
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    • v.50 no.1
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    • pp.1-6
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    • 2007
  • In the United States, The concept of designation for hospital facilities that care for newborn infants according to the level of complexity of care provided was first proposed in 1976. The extent of perinatal health care regionalization varies widely from one area to the other. facilities that provide hospital care for newborn are classified into three categories on the basis of functional capabilities; level I-primary or basic care, level II-secondary or specialty care, level III-tertially or subspecialty care. These facilities should be organized within a regionalized system of perinatal care. The transport system of newborn infants should be organized for referral of high risk newborn to centers with the personnel and resources needed for their degree of risk and severity of illness. In Korea, The korean society of neonatology was established and articulated in the 1994. During the past decade, the number of neonatologist has increased and neonatal intensive care units have proliferated in Korea. However, no standard definitions exist for the graded levels of complexity of care that neonatal intensive care units provide and no uniform guideline or recommendation for regionalization and referral system of high risk neonate have been established. With the rapid changing neonatal care system in Korea, the optimal neonatal care demands regionalization of care in utilization of manpower resources and in efficient use of advanced technology and facility.

Performance Characteristics of Small Tubular-type Hydroturbine according to the Guide Vane Opening Angle by Experiment and CFD (실험 및 CFD에 의한 가이드베인 개도에 따른 소형 튜블러 수차의 성능특성)

  • Nam, Sang-Hyun;Kim, You-Taek;Choi, Young-Do;Lee, Young-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.11 no.5
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    • pp.44-49
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    • 2008
  • As the alternative energy, renewable energy should have been developing by many techniques, in order to substitute the fossil fuel which will be disappeared in the near future. One of the small hydropower generator, main concept of tubular turbine is based on using the different water pressure levels in pipe lines, energy which was initially wasted by using a reducing valve at the end of the pipeline, is collected by turbine in the hydro power generator. A propeller shaped hydro turbine has been used in order to use this renewable pressure energy in order to acquire basic design data of tubular type hydraulic turbine, output power, head, efficiency characteristics due to the guide vane opening angle are examined in detail. First, it ensures the reliance of CFD by that of compared with experiment data. After all, the results of performance characteristics of the CFD and experiment show to confirm the data that power, head and efficiency of less than 4%, 2% and 5% respectively. Moreover influences of pressure, tangential and axial velocity distributions on turbine performance are investigated.

Pre-Combustion Capture of Carbon Dioxide Using Principles of Gas Hydrate Formation (가스 하이드레이트 형성 원리를 이용한 연소전 탈탄소화 연구)

  • Lee, Hyun-Ju;Lee, Ju-Dong;Kim, Yang-Do
    • Korean Journal of Materials Research
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    • v.18 no.12
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    • pp.650-654
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    • 2008
  • The emission of carbon dioxide from the burning of fossil fuels has been identified as a major contributor to green house emissions and subsequent global warming and climate changes. For these reasons, it is necessary to separate and recover $CO_2$ gas. A new process based on gas hydrate crystallization is proposed for the $CO_2$ separation/recovery of the gas mixture. In this study, gas hydrate from $CO_2/H_2$ gas mixtures was formed in a semi-batch stirred vessel at a constant pressure and temperature. This mixture is of interest to $CO_2$ separation and recovery in Integrated Coal Gasification (IGCC) plants. The impact of tetrahydrofuran (THF) on hydrate formation from the $CO_2/H_2$ was observed. The addition of THF not only reduced the equilibrium formation conditions significantly but also helped ease the formation of hydrates. This study illustrates the concept and provides the basic operations of the separation/recovery of $CO_2$ (pre-combustion capture) from a fuel gas ($CO_2/H_2$) mixture.

Velocity and Pressure Distributions of Tubular-type Hydroturbine for Variable Runner Vane Angle (러너베인 각도에 따른 튜블러 수차의 속도 및 압력분포)

  • Nam, Sang-Hyun;Kim, You-Taek;Choi, Young-Do;Nam, Chung-Do;Lee, Young-Ho
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2839-2844
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    • 2007
  • Micro hydraulic power generation of which the output is less or equal to a 100kW is attracting considerable attention. This is because of its small, simple, renewable, and abundant energy resources. By using a small hydropower generator of which main concept is based on using the different water pressure levels in pipe lines, energy which was initially wasted by use of a reducing valve at the end of the pipeline, is collected by turbine in the hydropower generator. A propeller shaped hydroturbine has been used in order to use this renewable pressure energy. In this study, in order to acquire basic design data of tubular type hydraulic turbine, output power, head, efficiency characteristics due to the flow coefficient are examined in detail. Moreover influences of pressure and velocity distributions with the variations of runner vane angle on turbine performance are investigated by using a commercial CFD code.

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Study on the Volume of a Sphere in the Historical Perspective and its Didactical Implications (구의 부피에 대한 수학사적 고찰 및 교수학적 함의)

  • Chang, Hye-Won
    • Journal for History of Mathematics
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    • v.21 no.2
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    • pp.19-38
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    • 2008
  • This study aims to investigate the evolution of calculating the volume of a sphere in eastern and western mathematical history. In western case, Archimedes', Cavalieri's and Kepler's approaches, and in eastern case, Nine Chapters';, Liu Hui's and Zus' approaches are worthy of noting. The common idea of most of these approaches is the infinitesimal concept corresponding to Cavalieri's or Liu-Zu's principle which would developed to the basic idea of Calculus. So this study proposes an alternative to organization of math-textbooks or instructional procedures for teaching the volume of a sphere based on the principle.

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Classification of Bodytype on Adult Male for the Apparel Sizing System (Part 4) -Bodytype of Lower Part of Trunk from the Photographic Data- (남성복의 치수규격을 위한 체형 분류(제4보) -사진 자료에 의한 하체부의 분류-)

  • 김구자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.6
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    • pp.1062-1070
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    • 1996
  • Concept of the comfort and fitness has become a major concern in the basic function of the ready-made clothes. Until now, ready-made clothes were not made by on the basis of the bodytype, but by the body size only. This research was performed to classify and characterize the bodytypes of Korean adult males. Sample size was 1290 subjects and their age range was from 19 to 54 years old. 15 variables from the photographic data of 1112 subjects were applied to analyse the bodytype of th\ulcorner lower part of trunk. Data were analyzed by the multivariate method, especially factor and cluster analysis. The groups forming a cluster can be subdivided into 5 sets by crosstabulation extracted by the hierarchical cluster analysis. 5 bodytypes classified by the photographic sources could be combined with the anthropcmetric data and were demonstrated with 5 silhouette. Type 2 and 3 in the lower part of trunk were dominant and were composed of the majority of 56.8% of the subjects. Bodytypes of Korean males were influenced by the degree of posture erectness and of curvature of the front side of the body in waist and abdomen.

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Strength Index in Seismic Performance Evaluation Method of Existing Reinforced Concrete Buildings (기존 철근콘크리트 건물 내진진단법의 강도지표)

  • 이원호
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.278-287
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    • 2000
  • In Korea, countermeasures against earthquake disasters such as the seismic performance evaluation and/or retrofit scheme of buildings have not been fully performed since Korea had not been experienced many destructive earthquakes in the past. However, due to more than four hundred earthquakes with slight/medium intensity occurred in the off-coastal and inland of Korea during the past 20 years, and due to the great earthquakes occurred recently in neighboring countries, such as the 1995 Hyogoken-Nambu Earthquake with more than 6,500 fatalities in Japan and the 1999 Ji-Ji Earthquake with more than 2,500 fatalities in Taiwan, the importance of the future earthquake preparedness measures in Korea is highly recognized. The main objective of this paper is to provide the basic data for development of a methodology for the future earthquake preparedness in Korea by investigating the concept and applicabilities of the Japanese Standard for Evaluation of Seismic Performance of Existing RC Buildings developed in Japan among the methodologies of all over the world. In this paper, a seismic performance evaluation method of the existing reinforced concrete buildings is proposed based on experimental data of columns and walls carried out in Korea by referring the Japanese Standard, especially focusing on the Strength Index(C) among the indices in the seismic capacity index(IS) equations. Also, the seismic capacities of two existing reinforced concrete buildings in Korea are evaluated based on the proposed methodology and the Japanese Standard, and the correlations between the seismic capacities by the proposed methodology and the Japanese Standard are discussed.

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A Study on the Collage's Concept Represented in Mies' Architecture Based upon Barcelona Pavilion and Tugendhat House (미스의 건축에서 재현된 꼴라쥬의 개념 - 바르셀로나 파빌리온과 투겐타트를 중심으로 -)

  • Jo, Seung-Koo;Lee, Byung-Wook
    • Journal of the Korean housing association
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    • v.16 no.4
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    • pp.45-55
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    • 2005
  • The cubist collagists proposed radically different ideas about the nature of order, and about the nature of artistic space. The collage substitutes an order which is constructed on relationships for the more rigid order of traditional art. Collage presents new theories of communication with the viewer, of relationships and of signs. This paper is an investigation of these ideas and how they have been applied to Mies Van der Rohe's making of architecture: Barcelona Pavilion and Tugendhat house. Collage in Mies' works has been executed in a limited manner. In Mies' works, one can begin to recognize some basic traits of collage. Textures, forms, and fragments begin to interact with each other and exploit those principles of contrast and juxtaposition that give collage a value as an expressive medium. Many of the formal aspects of collage are readily apparent in much of the work which we see around use today, but we should look at the attitudes and beliefs upon which collage is built for a further understanding of how its principles can be applied.

TTY Device Driver Model of User-Level (사용자 수준의 단말기 구동기 모델)

  • Lee, Hyeong-Ju;Im, Seong-Rak
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.6
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    • pp.815-822
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    • 1995
  • In the conventional UNIX system, the all device driver realized in the kern el. Hence, whenever we want to add a new device driver or change the existin g device driver, the modification of kernel is unavoidable. Generally, it is very difficult to modify the kernel codes.As a method of overcoming this difficulty, a TTY device driver model of user-level is presented in this paper. The basic concept of this model is providing a dynamic reconfiguration of TTY device driver by realizing a user-level server process for TTY device driver. In order to verify the proper y of this model, a prototype of TTY device driver has been realized in the SunOS and Linux environment and evaluated its performance.

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