• Title/Summary/Keyword: Byungki Kim

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Dissolution Characteristics of Liquid Carbon Dioxide Injected at the Intermediate Depth of the Ocean

  • Namjin Kim, Jaeyong-Lee;Byungki Hur;Taebeom Seo;Kim, Chongbo
    • Journal of Mechanical Science and Technology
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    • v.14 no.11
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    • pp.1276-1285
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    • 2000
  • The solubility, the surface concentration and the dissolution behavior of carbon dioxide in deep sea were numerically investigated. Base on the calculations the relations between the surface concentration of liquid carbon dioxide droplet with the hydrate film and the solubility and those between the ambient carbon dioxide concentration in the plume and the dissolution rate were obtained. The result show that a carbon dioxide droplet is released both at 1000 m in depth with the initial droplet diameter of 0.011 m or less and at 1500 m in depth with a diameter of 0.015 m or less, and the droplet is completely dissolved below 500 m in depth. The hydrate film acts as a resistant layer for the dissolution of liquid carbon dioxide, and the effect of the hydrate film on the dissolution of liquid carbon dioxide depended upon the depth.

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Object Recognition using Improved k-Nearest Neighbor (개선된 k-Nearest Neighbor를 이용한 물체 인식)

  • Jung Byeongsoo;Wi Seungjung;Kim Jonghyeuk;Kim Byungki
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07b
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    • pp.799-801
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    • 2005
  • 모델 영상내의 각각의 물체의 대표 값을 만든 후에 실험 영상을 물체 공간에 투영 시켜서 나온 성분과 대표 값의 거리를 비교하여 인식하게 된다. 그러나 단순히 기존의 방법인 Point to Point 방식인 단순 거리 계산은 오차가 많기 때문에 된 논문에서는 개선된 Class to Class방식인 k-Nearest Neighbor를 이용하여 몇 개의 연속적인 입력영상에 대해 각각의 모델영상들을 인식의 단위로 이용하였다.

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Art of Dislocation, Exile, and Diaspora: Korean Artists in New York in the 1960s and 1970s (1960-70년대 뉴욕의 한국작가: 이주, 망명, 디아스포라의 미술)

  • Yang, Eunhee
    • The Journal of Art Theory & Practice
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    • no.16
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    • pp.107-137
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    • 2013
  • This paper examines a number of Korean artists-Whanki Kim, Po Kim, Byungki Kim, Lim Choong-Sup, Min Byung-Ok and etc-working in New York in the 1960s and 1970s, focusing on their motivations to head for the U.S. and their life and activity in the newly-emerged city of international art. The thesis was conceived based upon the fact that New York has been one of the major venues for Korean artists in which to live, study, travel and stay after the Korean War. Moreover, the United States, since 1945, has had a tremendous influence upon Korea politically, socially, economically, and, above all, culturally. This study is divided into three major sections. The first one attends to the reasons that these artists moved out of Korea while including in this discussion, the long-standing yearning of the Korean intelligentsia to experience more modernized cultures, and American postwar cultural policies that stimulated them to envision life beyond their national parameters, in a country heavily entrenched in Cold War ideology. The second part examines these artists' pursuit of abstraction in New York where it was already losing its avant-garde status as opposed to the style's cutting edge cache in Korea. While their turn to abstraction was outdated from New York's critical perspective, it was seen to be de rigueur for Koreans that had developed through phases from Art Informel in the 1960s to Dansaekhwa (monochromatic paintings) in the 1970s. The third part focuses on the artists' struggle while caught between a dualistic framework such as Korea/U.S, East/West, center/margin, traditional/modern, and abstraction/figuration. Despite such dichotomic frames, they identified abstract art as the epitome of pure, absolute art, which revealed their beliefs inherited from western modernism during the colonial period before 1910-1945. In fact, their reality as immigrants in America put them in a diasporic space where they oscillated between the fixed, essentialist Korean identity and the floating, transforming identity as international artists in New York or Korean-American artists. Thus their abstract and semi-abstract art reflect the in-between identity from the diasporic space while demonstrating their yearning for a land of political freedom, intellectual fulfillment and the continuity of modern art's legacy imposed upon them over the course of Korea's tumultuous history in the twentieth century and making the artists as precursor of transnational, transcultural art of the global age in the twenty-first century.

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Development of Thermal Management System Heater for Fuel Cell Vehicles (연료전지 자동차용 TMS 히터 개발)

  • Han, Sudong;Kim, Sungkyun;Kim, Chimyung;Park, Yongsun;Ahn, Byungki
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.5
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    • pp.484-492
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    • 2012
  • The TMS(Thermal Management System) heater in a fuel cell vehicle has been developed to prevent a decline of fuel cell durability and cold start durability. Main functions of the COD(Cathode Oxygen Depletion) heater are depletion of oxygen in a cathode as heat energy and consumption of electric power for rapid warming up of a fuel cell stack. This paper covers subjects including the design specification of a heater, heater controller for detection of overheat and reliability assessment including coolant pressure cycle test of a heater. To verify the design concept, burst pressure and deformation analysis of plastic housing were carried out. Also, temperature distribution analysis of heater surface and coolant inside of housing were carried out to verify the design concept. By designing the plastic housing instead of a steel housing, the 30% weight lightening and 50% cost reduction were attained. A module-based design of a TMS system including a heater or reducing the watt density of a heater is a problem to be solved in the near future work.

Effect of Automobile Exterior Panel Stiffness on Customers' Affect : Focused on Hood and Door of Mid-Size Passenger Cars (자동차 외판 강성의 고객 감성 영향 분석 : 승용차의 후드 및 도어를 중심으로)

  • Ryu, Taebeum;Kim, Wonjun;Jin, Byungki;Yun, Myung Hwan
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.5
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    • pp.360-369
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    • 2016
  • This study attempted to identify the effect of the panel stiffness on the customers' affect, which was not addressed in the research field of affective engineering. For this, this study derived four affects related to the panel stiffness from literature and pre-experiment : hardness, deform consistency, thickness and satisfaction and prepared a questionnaire to evaluate the affects of the panel. In the experiment, 54 adults in the age of 20~50 participated and evaluated the affects of hood, front and rear door for nine full size and luxury sedans by pressing the panels with their hands. As results, participants' affect for the panels were significantly different depending on the force-deflection curves of them, and the subjects' satisfaction of the panels increased as the slope of the curve (stiffness) increases. In addition, it was found that the subjects evaluated the panel with the pressing force up to 14kgf. The findings of the study can be used to increase and control the affective quality of exterior panels on passenger cars.

Research And Improve Agile Development Methods Based On Teamwork (팀워크 바탕으로 애자일 개발방법의 개선연구)

  • Xiang, Chen;Kim, Byungki
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.5
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    • pp.303-310
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    • 2013
  • Agile software development methodology is a lightweight software development method, plays an important role in the software development team. In this paper, we propose programs that in when agile development co-operation, team management, team collaboration and project management tasks can be high efficiency and allocation of human resources. The proposed model, the use of 6-Sigma priority assignment, established a mathematical model of the operation and distribution of human resources is the most reasonable people go to work. Cooperation makes team-based agile development can improve efficiency. This method improve staff efficiency by teamwork to improve the productivity of software development.

PRODUCTIVITY PREDICTION MODEL BASED ON PRODUCTIVION INFLUENCING FACTORS: FOCUSED ON FORMWORK OF RESIDENTIAL BUILDING

  • Byungki Kwon;Hyun-soo Lee;Moonseo Park;Hyunsoo Kim
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.58-65
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    • 2011
  • Construction Productivity is one of the most important elements in construction management. It is used in construction process scheduling and cost management, which are significant sector in construction management. It is important to make appropriate schedule and monitor how works are done within schedule. But construction project contains uncertainty and inexactitude, modifying construction schedule is being an issue to manage construction works well. Even though prediction and monitoring of productivity can be principal activity, it is hard to predict productivity with manager's experience and a standard of estimate. A large number of factors influencing productivity, such as drawing, construction method, weather, labor, material, equipment, etc. But current calculation of productivity depends on empirical probability, not consider difference of each influencing factor. In this research, the aim is to present a productivity predicting regression model of form work, which includes effectiveness of influences factors. 5 variables existed inside form work are selected by interview and site research based on literature review of existed various productivity influencing factors. The effectiveness and correlation of productivity influencing factors are analyzed by statistical approach, and it is used to make productivity regression model. The finding of this research will improves monitoring and controlling of project schedule in construction phase.

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A study on advanced PV operation algorithm to improve the PV Power-Hardware-In-Loop Simulator (PV PHIL-시뮬레이터의 성능 개선을 위한 최적의 운영제어 알고리즘 연구)

  • Kim, Dae-Jin;Kim, Byungki;Ko, Hee-Sang;Jang, Moon-Seok;Ryu, Kyung-Sang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.9
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    • pp.444-453
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    • 2017
  • This paper proposes an operational algorithm for a Photovoltaic Power-Hardware-In-Loop Simulator that is designed to improve the control algorithm and reliability of the PV Inverter. There was an instability problem in the PV PHILS with the conventional algorithm when it was connected tothe PV inverter. Initially, a real-time based computing unit with mathematical modeling of the PV array is implemented and a DC amplifier and an isolated device for DC power measurement are integrated. Several experiments were performed based on theabove concept undercertain conditions, which showed that the proposed algorithm is more effective for the PV characteristic test and grid evaluation test than the conventional method.

Analysis of Customer Power Quality Characteristics Using PV Test Devices (태양광전원 계통연계시험장치에 의한 수용가 전력품질특성에 관한 연구)

  • Kim, Byungmok;Kim, Byungki;Park, Jeabum;Rho, Daeseok
    • Journal of the Korea Convergence Society
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    • v.2 no.4
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    • pp.21-27
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    • 2011
  • Recently, new distributed power sources such as photovoltaic, wind power, fuel cell systems etc. are energetically interconnected and operated in the distribution feeders, as one of the national projects for alternative energy. When new power sources are considered to be interconnected to distribution systems, bi-directional power flow and interconnection conditions of new power sources may cause several power quality problems like voltage sag, voltage swell, harmonics, since new power sources can change typical characteristics of distribution systems. Under these situations, this paper deals with the analysis the power quality problems at primary and secondary feeders in distribution systems, when new power sources like photovoltaic (PV) systems are interconnected, by using the test devices for PV systems based on the LabVIEW S/W. This paper presents the test device which is consisted with model distribution system and model PV systems. By performing the simulation for power quality operation characteristic based on the test facilities, this paper presents the optimal countermeasures for power quality.

Decrease of PEMFC Performance by SO2 in Air (공기 중 SO2에 의한 고분자전해질 연료전지의 성능 감소)

  • Lee, Ho;Song, Jinhoon;Kim, Kijoong;Kim, Saehoon;Ahn, Byungki;Lim, Taewon;Park, Kwonpil
    • Korean Chemical Engineering Research
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    • v.48 no.3
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    • pp.311-315
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    • 2010
  • The effects of $SO_2$ on the performance of proton exchange membrane(PEMFC) were investigated by introduction air containing $SO_2$ into cathode inlet of PEMFC. And the recovery of the cell performance by applying clean air, cycle voltammetry(CV) and high voltage holding following exposure contaminated air was studied. The $SO_2$ concentration range used in the experiments was from 20 ppb to 1.3 ppm. The performance degradation and recovery were measured by constant-current discharging, I-V polarization and electrochemical impedance spectroscopy(EIS). The cell voltage gradually decayed with time and decreased by 17 mV after 200 hours of 20 ppb $SO_2$ injection. The cell performance can be recovered partially by clean air flushing, CV and high voltage holding due to desorption of S from Pt catalyst.