• Journal of the Korean Society for Precision Engineering
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• v.8 no.3
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• pp.27-43
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• 1991

연소 가공은 고품질 고정도를 필요로 하는 경우 매우 유효한 가공방법이지만 그 공정이 많은 Parameter에 의해 구성되기 때문에 동일한 조건에서도 정량적인 평가가 어려우므로 작업현장 에서는 과학적 원리와 공학적 지식 보다는 숙련자의 경험과 기능에 의존하고 있는 실정이다. 본 연구에서는 이와 같은 국면에 대처한 문제 해결을 위해 Computer가 인간사고에 근접 할 수 있도록 Fuzzy 이론과 Default 이론을 도입하고 전문가의 이론적 지식과 숙련자의 감각적 지식을 적극 수용 하여 연소용 Expert system (최적 가공 조건의 설정 System과 Trouble shooting system)을 개발하였다. 또한 연소 가공 Data의 불확실한 애매성을 효과적으로 이용 할 수 있도록 Fuzzy 가능성이론에 의해 가공 Datad을 회귀 분석하여 실가공 Data base에 축적시켜 재활용토록 설계하었으며 개발된 본 System 의 실행 결과 그 활용성이 높음을 입증하였다.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.75-78
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• 1999

To obtain direct evidence for thed involvement of C-AB13, a carrot (Daucus carota L.) homolog of VPI/Ab13, seed-specific transcription factor, in the acquisition of desiccation tolerance carrot non-embryogenic cells (NC) in which the C-AB13 gene was expressed ectopically was prepared. Non-transgenic NC, in which expression of C-AB13 was not detected, did not exhibit desiccation tolerance even after treatment with abscisic acid (ABA). In transgenic NC that expressed C-AB13, embryo-specific ABA-inducible genes (ECP genes) were expressed upon ABA-treatment. Furthermore, the transgenic NC became desiccation-tolerant upon ABA-treatment, but not tolerate desiccation without ABA-treatment. These results provide direct evidence for the involvement of C-AB13 in the ABA-induced acquisition of desiccation tolerance.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.1-6
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• 1994

Many useful biomaterials like enzymes are contained in yeast cells. However, the release of these intracellular biomateriais from the cells is required to recover them with hot water, solvent or various cell breakage methods of mechanical or non mechanical ones. The cell lysis or breakage of yeast is usually made by solvent like ethyl acetate and mechanical disintrgration with high pressure homogenizer or agitating beads mill. The separation of cell debris (i.e. solid liquid separation) is done by centrifuge or membrane depending on the recovery conditions. The features of both separation methods are shown in Tables 1 and 2. As it is often difficult to obtain a clear supernatant by centrifuge from the suspension containing cell debris, the membrane separation is also often used to gel a clear supernatant. In this report we introduce the several applications of membrane separation to separate the cell debris of yeast disintegrated chemically or mechanically and to recover the intracellular biomaterials.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.2
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• pp.37-44
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• 2009

It is well known that a refrigerant-induced noise is caused by two-phase flow in the indoor unit of a heat pump air-conditioner. Especially when the flow pattern in a pipe is intermittent flow, the irregular noise occurs frequently. But it is very difficult to avoid this kind of the noise for the application of air-conditioner. Therefore, in this research, the flow patterns at two-phase flow state in a pipe of the indoor unit for the air-conditioner are researched using cycle simulator at typical cycle conditions. In order to find the relationship between refrigerant-induced noise and flow pattern, the noise patterns are investigated with respect to the estimated flow pattern from the various flow pattern maps. Base on the estimations of the flow patterns by those maps, the refrigerant-induced noise is evaluated as decreasing tube diameter, which can transit the flow pattern from slug to annular flow.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.1-13
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• 2011

In operating a turbomachine at off-design conditions various instabilities caused by anomalous flow phenomena occur and sometimes lead to the damage of a turbomachine. In order to avoid these phenomena various devices characteristic to each phenomenon have been developed, however they make turbomachines large-sized and cause efficiency drop. The present author has developed a very simple and innovative device, termed "J-groove," of suppressing various anomalous flow phenomena commonly by controlling the angular momentum of the main flow. It has been revealed that J-groove makes an operation of a turbomachine stable in all flow range, causes little efficiency drop, and can be easily applied to an existing machine. Here is reviewed totally the results of suppressing various anomalous flow phenomena in turbomachines.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.7
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• pp.437-443
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• 2004

In this work the AC loss measurement setup based on an iron core background magnet, not used in a conventional one, has been successfully developed. To prove its validity, a round-robin test for the same Bi-2223 tape sample among three institutes has been done. The results show that the self-field and magnetization losses from the developed setup well agree with the losses measured at two other institutes of Korea Basic Science Institute and Yokohama National University. The measured magnetization losses for parallel or perpendicular fields can be well predicted from the slab model or the strip model for a filamentary region. However the magnetization losses for longitudinal fields can be rather predicted by the slab model for a decoupled filament. The self-field losses are well explained by the Norris ellipse model.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.169-172
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• 1985

Defectamerus soonkii sp. nov. and D. crassisetiger coreanus subsp. nov. belonging to the family Ameridae are described. Key to the species of the genus Defectamerus Aoki is presented.

• The Korean Journal of Ceramics
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• v.2 no.2
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• pp.111-113
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• 1996

Dielectric properties at microwave frequency region of the five-layered compound $Ba_5Nb_4O_{15}$ prepared by the conventional solid state reaction method were investigated. $Ba_5Nb_4O_{15}$ has excellent microwave dielectric characteristics; ${\varepsilon}_r$=38, Q=7500 at 10 GHz, and ${\tau}_l$=+50 ppm/K. Since this compound has a high dielectric constant, high Q and sufficiently stable characteristics, it is useful for the applications at microwave frequencies.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2007.10b
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• pp.94-98
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• 2007

Mountains have been playing an important role in the Japanese culture. It is important from landscape planning perspectives to maintain mountains in the proximity of cities. In this thesis, the geographical perception of residents in Kohoku New Town has been studied. Geographical changes before and after the Kohoku New Town development were clarified first. Following these clarifications, interviews with residents who moved into the area before and after the development were conducted. In this investigation, the interviewees were asked about mountains, valleys, hills, and slopes; and the areas that they recognize on the map were then specified. From these results, the mountain area which residents recognize and the actual geographical features were compared. The geographical characteristics of the mountains that the residents recognize were revealed, and the perception of mountains was defined. Not only did geographical features and vegetation affect the perception of mountains, but also residents' personal experiences were important. As a result, new information for future geographical landscape planning has been obtained.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.19-24
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• 2008

Many types of disasters are related to environmental problems. Today, frequently occurring disasters and global environmental problems have begun to threaten human life and welfare. Consequently, building sustainable communities requires assessing relationships between environmental problems and disasters using a broad, open approach and with a long-term perspective. This paper attempts to identify the need for conceptualizing disasters and environmental problems together by comparing mechanisms of both disasters and environmental problems, and attempts to integrate both of these seemingly different types of phenomena as similar types of risk threatening human existence. Based on this work, a chart is proposed for qualitatively organizing disasters, environmental problems and their mutual influences, as well as providing a framework for potential quantitative analysis. It is hoped this research serves to contribute to effective mitigation to both disasters and environmental problems in today's age of global environmental issues.