• 대한수학회지
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• 제43권5호
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• pp.967-990
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• 2006

In this paper, we evaluate first variations, conditional first variations and conditional Fourier-Feynman transforms of cylinder type functions over Wiener paths in abstract Wiener space and then, investigate relationships among first variation, conditional first variation, Fourier-Feynman transform and conditional Fourier-Feynman transform of those functions. Finally, we derive the conditional Fourier-Feynman transform for the product of cylinder type function which defines the functions in a Banach algebra introduced by Yoo, with n linear factors.

• 한국작물학회지
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• 제44권3호
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• pp.197-200
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• 1999

In order to get abundant germplasm for develop- ing new corn varieties, major morphological characteristics of ear were evaluated with a total of 210 Korean indigenous maize lines collected from various parts of Pusan City and Kyungnam Province, Korea. The ear shape of Korean indigenous maize was mainly cone type or similar to cone type. Cylinder type or similar to cylinder type of corn was collected from the north-west mountainous. region of Kyungnam Province, whereas cone type or similar to cone type was collected from the plain region. In the kernel colors of each ear, ears with mono colored kernels were 55.7% of the total, and ears with two to four mixed colors were 44.3%. Among the mono colored ears, brown was the most abundant at 16.8%. There was an average of 12∼14 rows per ear. Kernal rows per ear varied from 8∼20. Waxy corn was predominant at 67.2%, mixed corn with waxy kernel and common kernel at 11.0%, and common corn at 21.8%.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.314-318
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• 2011

Arm-type implements of tractor are mainly utilized for the slope land operation. The proposed hydraulic system was implemented to arm-type implements of tractor. An experiment was conducted to evaluate response characteristics of the designed arm-type implement control system attached by three-point hitch of tractor at various conditions, such as engine speed, pumping rate and cylinder input flow. Effects of the valve response time didn't affect engine speed. The flow rate of pump and cylinder changed to the pressure loss. Also, the pressure loss was within 2 MPa and the response characteristic was sufficient enough to use as the arm-type implement system.

• Journal of Advanced Marine Engineering and Technology
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• 제23권5호
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• pp.686-692
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• 1999

For the purpose of increasing compressed air pressure higher than 30bar lightening weight and decreasing installation area of air compressor used for shipboard and industrial power plant it is necessary to arrange its cylinders as a w-type or v-type construction multi-stage compression pro-cess more than two stages and to increase its operation speed higher than 1200rpm In this recip-rocating type air compressor operated in high speed having a crank mechanism and complicate cylinder arrangement there is a vibration problems which can be solved by balancing its recipro-cating parts with balance weight and approriate arranging of cylinder's arrangement angles.

• 한국수산과학회지
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• 제23권4호
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• pp.310-314
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• 1990

본 실험에서는 민꽃게 통발의 가장 바람직한 형 및 구조를 확정하기 위해 사구원통형과 사구각주형 통발을 고안하고, 수조실험 및 해상실험을 통해 그들의 민꽃게 유입성능 및 어획성능을 재래의 이구각주형 및 이구원통형 통발과 비교하였다. 그 결과, 수조실험을 통한 유입성능은 사구식에서 좋고 이구식에서 나쁜 경향이었는데, 구체적으로는 이구식의 경우 각주형보다 원통형에서 약간 더 좋았고, 사구식의 경우는 원추형보다 각주형에서 약간 더 좋았다. 해상실험을 통한 어획성능도 전체적으로는 비슷하였는데, 사구원추형이 이구원통형과 어획의 유의차가 없다는 것만이 달랐다. 따라서, 민꽃게 통발의 가장 바람직한 형은 사구각주형이라는 것을 알 수 있었다.

• 한국가스학회지
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• 제16권2호
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• pp.18-24
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• 2012

본 연구는 Type II 가스실린터의 20,000 회 피로시험과 파열시험시 음향방출시험을 병행하여 용기의 손상정도를 평가하고자 하였으며, 실험에 사용된 용기는 결함 크기가 $3mm{\times}3mm{\times}50mm$ (폭${\times}$깊이${\times}$길이)이고 결함 방향이 용기의 종방향 및 횡방향인 인공결함용기와 건전한 용기 등 세 종류이다. 피로시험시 발생된 음향방출신호는 종방향결함의 경우 전체 신호 중 결함에서 발생된 이벤트의 비율이 50 % 이상이며, 음향방출신호의 위치표정도 매우 정확하게 일치하였다. 또한 파열시험에서는 인공결함용기가 결함 위치에서 에상파열압력보다 낮은 압력으로 파열될거라는 예상과는 달리 인공결함용기의 파열압력은 건전한 용기와 큰 차이가 없었으며, 단지 종방향 인공결함용기의 경우 파열위치가 결함 위치와 근접하게 발생하였다. 이는 종방향 결함의 길이만큼 복합재료의 두께가 얇아지는 효과로 나타나게 되어 금속라이너의 피로반복시 결함 발생과 성장위치에 영향을 미친 것으로 판단된다.

• 대한수학회지
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• 제35권4호
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• pp.945-960
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• 1998

This paper is concerned with investigating the asymptotic behavior of end effects for a generalized heat conduction problem with an added dissipation term defined on a three-dimensional semi-infinite cylinder. With homogeneous Dirichlet conditions on the lateral surface of the cylinder it is shown that solutions either grow exponentially or decay exponentially in the distance from the finite end of the cylinder. In particular, to render decay estimate explicit, we pattern after the analysis of Payne and Song [13, 15]. The continuous dependence effect of perturbing the equations parameters is also investigated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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• pp.232-236
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• 1993

The Tunnel Form(T/F) system instead of traditional euro form has been tried to reduce construction duration and to improve concrete quality in reinforced concrete wall type apartment construction. To find the relationship for concrete compressive strength between cylinder mold and slab, the different curing locations of concrete cylinder mold in the room have been investigated. The test results showed that the compressive strength of the cylinder concrete with middle-upper location in the room was most near concrete compression strength with respect to slab concrete strength.

• 유공압시스템학회논문집
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• 제7권2호
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• pp.13-18
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• 2010

To improve the performance of the bent-axis type axial piston pump driven by the tapered piston, it is necessary to know the driving characteristics and mechanism of the tapered piston and the cylinder block. Since each piston not only rotates on its axis and reciprocates in the cylinder bore, but also revolves around the axis of the driving shaft, it is difficult to analyze the driving mechanism theoretically. The theoretical mechanism for the bent-axis type axial piston pump is studied by using the geometrical method. The driving range of the tapered piston is determined by theoretical equations. The experimental results show that the cylinder block is driven by one tapered piston in a limited range and the core parameters such as driving factor of the piston and the ahead delay angle influenced performance of the bent-axis type axial piston pump.

• Journal of Mechanical Science and Technology
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• 제17권12호
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• pp.2027-2033
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• 2003

The purpose of this study is to investigate the stratification of fuel vapor with different in-cylinder flow, piston cavity and injection timings in an optically accessible engine. Three different piston shapes that are F(Flat), B(Bowl) and R(Re-entrance) types were used. The images of liquid and vapor fuel were captured under the motoring condition using Laser Induced Exciplex Fluorescence technique. As a result, at early injection timing of 270 BTDC, liquid fuel was evaporated faster by tumble flow than swirl flow, where most of fuel vapor were transported by tumble flow to the lower region and both sides of cylinder for the F-type piston. At late injection timing of 90 BTDC, tumble flow appears to be moving the fuel vapor to the intake side of the cylinder, while swirl flow convects the fuel vapor to the exhaust side. The concentration of mixture in the center region was highest in the B-type piston, while fuel vapor was transported to the exhaust side by swirl flow in F and R-type pistons. At the injection timing of 60 BTDC, the R-type piston was better for stratification due to a relatively smaller bowl diameter than the others.