• 한국초전도ㆍ저온공학회논문지
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• 제3권2호
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• pp.44-48
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• 2001

SMES consists of Superconducting magnet, a power converter, a cryostat and HTS current leads The prototype cryostat with HTS current leads and refrigerators was designed and manufactured for developing micro SMES. The temperature rise under dc current in HTS current leads was measured. The performances of helium boil-off and mechanical stress were evaluated during transfer and vibration tests. The results will be used to develope the micro-SMES system.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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• pp.55-57
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• 2000

In this paper we present the results of tests for the high-Tc superconducting (HTS) power cable core. A prototype HTS cable cores have been constructed using Bi-2223 based Ag-sheathed HTS tapes. HTS cable cores has been tested at 77K with DC currents. Results shows that the cable cores carrying up to 700A DC and self-field effects are discussed.

• 한국정밀공학회지
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• 제25권11호
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• pp.126-133
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• 2008

Rapid Prototyping (RP) has been widely used for rapid development of prototypes in various industrial fields. In recent years, a new requirement in RP industry has issued so as to directly manufacture a functional prototype which has enough mechanical properties to be used as a functional part. The RP prototype, however, has a limitation in mechanical properties due to its layer-by-layer manufacturing process. This manufacturing process results in anisotropy of the prototype, especially showing weakness in the building direction. In the present work, we performed tensile tests for RP prototypes in order to determine directional mechanical properties. The test specimens were made by using $Eden330^{TM}$ by Object Geometries Ltd. Finite element analyses considering material anisotropy were then carried out for RP prototypes with various building directions. Effect of the building direction on the mechanical strength was investigated through the analysis, and compared with experimental results.

• Journal of Biosystems Engineering
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• 제34권6호
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• pp.411-419
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• 2009

This study was carried out to develop a shredding-burying machine for application of gramineae green manure crops that were tall and had high biomass yield such as sudan grass and rye. We made a prototype to operate both shredding and burying concurrently to attach at middle-sized tractors. Field tests were performed with the prototype to treat rye and sudan grass. The test results showed that the average cutting length became shorter and the quantity of entwined stem became obviously decreased when the PTO shaft speed was fast and running speed was slow. Also, We found, when the cut stem length became shorter, the burying ratio became more increasing and the PTO power requirement became more decreasing. Working efficiency of the prototype was better than conventional Rotary. The test results for treating rye/sudan grass with prototype showed that average cutting length was 21.2/22.5 cm and burying ratio was 98.4/98.1% when the PTO shaft speed was 1,000/1,000 rpm and running speed was 0.25/0.17 m/s. Also, the working performance of the prototype was 0.79 and 1.14 h/10 a for rye and sudan grass, respectively. Finally, we found that the prototype of shredding-burying machine was better for labor than conventional method that required at least 3 times bigger tractor.

• Spatial Information Research
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• 제19권3호
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• pp.83-93
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• 2011

도시의 기반 시설은 국가 또는 도시의 기술적인 발전 정도를 표현하는 지표적인 의미를 가지므로 이들을 효과적으로 관리하고 운영하는 것은 매우 중요하다. 본 논문에서는 u-City에서 지능적으로 도시의 지하 시설물을 관리하기 위한 상황인식 시스템을 제안하고, 이에 대한 알고리즘 및 프로토타입(prototype)을 개발한다. 제안된 상황인식 시스템의 알고리즘 작성은 USN(ubiquitous sensor network)환경에서 시설물을 관리하고 있는 각종 센서가 이상 신호를 감지하여 알람을 발생시킨 시점부터 상황인식 시스템이 발생한 알람의 원인을 찾아낸 후 그 결과를 도시공간정보 통합 플랫폼과 주변의 모듈에 전송해 주는 시점까지이다. 그리고 이 알고리즘을 기반으로 동작하는 상황인식 시스템의 프로토타입을 구현한 후 단위 테스트를 수행하여 구현된 프로토타입의 유효성을 검증하였다. 본 논문에서 구현된 지하시설물의 관리를 위한 알고리즘과 프로토타입은 검증 및 수정 작업을 거친 후 실제적인 시스템 개발로 연결될 것이며, 도시의 여러 가지 시설물을 관리하는 관련 시스템들의 참조모델로서 유용하게 사용될 것이라 기대한다.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.320-330
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• 2018

Purpose: The aim of this study was to investigate the harvesting performance of a prototype small combine for buckwheat and adlay. Methods: The prototype small combine was designed and constructed. Its ratio of grain loss, ratio of output components in the grain outlet, and field capacity for harvesting buckwheat and adlay were analyzed through field tests. Results: The prototype small combine required a working width of about 0.6 to 0.7 m to harvest buckwheat. The maximum travel speed was about 0.36 m/. The total ratio of grain loss was about 21.6%, which consisted of 8.8% at the header and 12.8% at the dust outlet. The grain and the material other than grain (MOG) ratios at the grain outlet were 94.1% and 5.9% respectively. In the case of adlay harvest, the maximum working width was about 1.2 m, that is, two rows. The range of maximum travel speed was about 0.45 to 0.46 m/s. When adlay was harvested in one row, the total ratio of grain loss ranged from 36.3 to 42.8% according to the cutting height. The cutting height of 30 cm resulted in a higher total ratio of grain loss than 60 cm and 90 cm. When the cutting height was 60 cm, there was no significant change in the total ratio of grain loss according to the number of working rows and the stage of the primary transmission shift. The total ratio of grain loss ranged from 35.2 to 37.7%. The grain and the MOG ratios at the grain outlet ranged from 93.1 to 95.8% and from 4.2 to 6.9%, respectively. No significant difference was observed in relation to cutting height, number of working rows, and the stage of the primary transmission shift. Conclusions: The prototype small combine for harvesting miscellaneous cereal crops showed good potential for the efficient harvesting of buckwheat and adlay. However, to improve the harvesting performance, there seems to be a need to develop new crop varieties suitable for machine-based harvesting and improve the transmissions, reels, separation/cleaning systems.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.420-422
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• 2004

This paper reports the results of performance verification tests of the base isolated RC building with the laminated rubber bearings which is manufactured by Dongil Rubber Belt Co.. The shaking table tests were performed using a scaled 3-story model scaled to 1/3 of the prototype RC apartment building. Several major earthquake records were scaled to different peak ground accelerations and used as input base excitations. Through the verification tests, the validity of the applied base isolation device and the response reduction effect against earthquakes are confirmed.

• Wind and Structures
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• 제17권6호
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• pp.565-587
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• 2013

Obvious vortex induced vibration (VIV) was observed during section model wind tunnel tests for a single main cable suspension bridge. An optimized section configuration was found for mitigating excessive amplitude of vibration which is much larger than the one prescribed by Chinese code. In order to verify the maximum amplitude of VIV for optimized girder, a full bridge aeroelastic model wind tunnel test was carried out. The differences between section and full aeroelastic model testing results were discussed. The maximum amplitude derived from section model tests was first interpreted into prototype with a linear VIV approach by considering partial or imperfect correlation of vortex-induced aerodynamic force along span based on Scanlan's semi-empirical linear model. A good consistency between section model and full bridge model was found only by considering the correlation of vortex-induced force along span.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.549-556
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• 2002

Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(shore protection structure, detached breakwater, groins and jetty). It can also be used to isolate contaminated material from harbor, detention basin dredging, and to use this unit as dikes for reclamation work. Recently, new preliminary design criteria supported by model and prototype tests, and some stability analysis calculations have been studied. The stability analysis of geotextile tube is composed geotechnical and hydrodynamic analysis. The stability check points are sliding failure, overturning, bearing capacity failure against the wave attack. In this paper presented the construction procedure and in-situ measurement(properties of filling material, effective height variation, stress variation at geotextile tube bottom) of geotextile tube at Young-Jin Bay and stability analysis by theoretical method and hydraulic model tests

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.784-793
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• 2006

As the number of CFRD constructions increases, the necessity of an accurate assessment on its behavior also has been increasing accordingly. The performance of concrete faced rockfill dam (CFRD) under different water levels is greatly concerned by dam engineers and designers in the world. However, domestic research on CFRD design and construction has yet been insignificant. This study deals with three centrifuge model tests, mainly investigates the deformation of the concrete faced slabs with different face slab stiffness under different water levels. The prototype of a centrifugal model dam is half size of domestic CFRD dam. Detailed material preparation, model design, model set-up, model instrumentation and testing procedures are presented. In order to simulate the prototype concrete faced slab, three kinds of thin fiberglass plates with different thickness was adopted in the three model tests. The water level control facility was specially designed for this experiment to control the water level rise and drawdown during centrifuge flight. Although most of the results from the three model tests are satisfactory, it is also required that the centrifuge test results should be compared with those of numerical analysis and field measurements to analyze the centrifuge test results more in detail.