• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.117-122
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• 1988

다른 生長條件(growth chamber, outdoor)과 室素施肥條件(N O, N 60kg $ha^{-1}$에서 자란 perennial ryegrass잎에 있어서 葉伸長率(LER)과 伸長部位의 空間的 移動 및 細胞의 伸長등을 알아보고자, 잎 基部내 伸長部位의 0~30mm에 pin 처리를 하고 일정시간후 pin hole의 이동거리로서 生長을 조사하였으며 표면복제방법에 의해 細胞의 길이를 측정하였다. Growth chamber에서 자란 목초의 LER은 25.2mm day$^{-1}$(outdoor 목초에 비해 54.6% 증가), 생육의 공간분포는 基部로부터 24mm까지, 최대생육은 10~13mm에서, 세포신장은 20mm까지로 관찰되었다. Outdoor 목초는 LER 16.3mm, 생육분포는 17mm까지, 최대생육은 5~8mm에서, 세포신장은 14mm까지였다. 질소시비구 목초의 LER은 30.3mm day$^{-1}$(무시비구 목초에 비해 61.2% 증가), 생육분포는 基部로부터 27mm까지, 최대생육은 13~15mm에서, 세포신장은 21mm까지였으며, 질소무시비구 목초는 LER 21.3mm, 생육 분포는 21mm까지, 최대생육은 8~11에서, 세포신장은 16mm까지였다. Ligule 부위의 세포길이는 현저히 짧아졌으며, LER이 빠를때 伸長部位내 生育의 移動速度도 빨랐다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.3
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• pp.117-122
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• 1988

다른 生長條件(growth chamber, outdoor)과 室素施肥條件(N 0, N 60kg $ha^{-1}$')에서 자란 Perennial rye- grass잎에 있어서 葉伸長率(LER)과 伸底部位의 空間的 移動 및 細胞의 伸長등을 알아보고자, 잎 基部내 伸長部位의 O~30mm에 pin처리를 하고 일정시간후 Pin hole의 이동거리로서 長을 조사하었으며 표면복 제방법에 의해 細胞의 길이를 측정하였다. Growth chamber에서 자란 목초의 LER은 25.2mm $day^{-1}$(outdoor 목초에 비해 54.6% 증가), 생육의 공 간분포는 基部로부터 24mm까지, 최대생육은 10~13nm에서, 세포신장은 20nm까지로 관찰되었다. Outdoor 목초는 LER 16.3nm, 생육분포는 17mm까지, 최대생육은 5 ~8mm에서, 세포신장은 14mm까지었다. 질소시비구 목초의 LER은 30.3nm$day^{-1}$(무시비구 목초에 비해 61, 2% 증가), 생육분포는 基部로부터 27 mm까지, 최대생육은 13~1Smm에서, 세포신장은 21mm까지었으며, 질소무시비구 목초는 LER 21.3mm, 생육 분딘는 21mm까지 최대생육은 8~llmm에서, 세포신장은 16mm까지였다. Ligule 부위의 세포길이는 현저히 짧아졌으며, LER이 빠를때 伸長部位내 生育의 移動速度도 빨랐다.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.8
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• pp.669-681
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• 2016

Mechanical designers often make mistakes that result in unwanted over-constraints, causing difficulty in assembly operations and residual stress due to interference among parts. This study is concerned with detection and elimination of over-constraints. Screw theory is a general method that is used for constraint analysis of an assembly and motion analysis of a mechanism. Mechanical assemblies with plane-plane, pin-hole, and pin-slot constraint pairs are analyzed using screw theory to illustrate its utility. As a real-world problem, a ball valve design is analyzed using the same method, and several unwanted over-constraints are detected. Elimination measures are proposed. Nominal dimensions of some parts are adjusted, and dimensions and tolerances of the pins and holes are modified using the virtual condition boundary concept. The revised design is free of over-constraints. General procedure for applying screw theory to constraint analysis is established and demonstrated; it will contribute to improving quality of assembly designs.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.1
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• pp.80-83
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• 2017

In this paper, the X-band reconfigurable frequency selective surface having flexible geometry was proposed. The proposed RFSS is composed of patterns of cross-shaped loop with inductive stub, which can control the frequency response for C-Band and X-band by ON/OFF state of PIN diode. To minimize the parasitic effect and to obtain the high level of isolation between the unit cell of FSS and the bias circuit, we designed the grid type bias line on bottom layer through via hole. The measured transmission characteristics show good agreement with the simulation results and good stability of frequency response for different incident angles and curvatures of surface.

• Journal of Korean Association for Spatial Structures
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• v.7 no.6
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• pp.61-68
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• 2007

The hole for the insertion of the pin in the shank is exist at ball joint connection of the space frame. It brings about the brittle fracture caused by stress concentration. Consequently it cannot expect the deformation performance or energy absorption performance from ball joint connection. In this study we developed a new connection details which will increase the plastic deformation performance at ball joint connection and can absorb the error in construction, which expect the plastic deformation performance at the reduced shank without brittle fracture at the screw of bolt and pin. Also it's capacity is verified by the performance in numerical analysis and test. We confirmed bolt's plastic deformantion performance through controled shank and pin's area.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.383-387
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• 2004

The Fuel Test Loop (FTL) consists of In-Pile Test Section (IPS) and Out-of-Pile System (OPS). The test condition in IPS such as pressure, temperature and quality of the main cooling water, can be controlled by the OPS. The FTL has been developed to be able to irradiate three pins to the core irradiation hole (IR1 hole) by considering for its utility and user's irradiation requirement. The IPS vessel assembly (IVA) consists of IPS head, outer pressure vessel, inner pressure vessel, inner assembly and test fuel carrier. The IVA is approximately 5.6 m long and fits within a 74 mm in diameter envelope over the full height of the chimney. Above the top of the chimney, the head of the IPS is enlarged to allow the closure flanges and pipe work connections. IVA was designed to test the CANDU and PWR nuclear fuel pin together. Specially, wished to minimize interference by nuclear fuel change in design and synthesize these items and shape design for IVA.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.69-78
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• 2008

Shearing strength test in tension type was investigated to determine the shear resistance of bolt and drift-pin connection of domestic larix glulam. The specimen was connected with bolt and drift-pin in the inserted plate type, and only bolt in the side plate type. The diameter of bolt and drift-pin used in the experiment are 12, 16 and 20 mm. The hole of bolt was drilled at the end-distance 5 d and 7 d. Tension load was loaded in the direction parallel to grain. The shear resistance was evaluated according to end-distance through this, the yield load was compared with the experimental yield load, using Larsen's formula. The prototype design strength is based on the yield load of end-distance 7 d and the reduction factor of end-distance 5 d was calculated. The results were as follows. 1. The average of maximum load of drift-pin connection was higher by 3~30% at the inserted type than at bolt connection with increasing diameter. In bolt connection, the average of maximum load of the side type was 1.54~2.07 times higher than that of the inserted type. In the same diameter, the average of maximum load of end-distance 7 d was higher by 8~44% than that of 5 d. 2. The bearing stress was 1.16~1.41 times higher at the inserted connection than at drift-pin connection, and 1.37~1.86 times higher at 7 d than at 5 d. Also, when the slenderness ratio was below 7.5 at drift-pin connection and below 6.0 at inserted connection, the lateral capacity was good. 3. The ratio of the experimental yield load and the predicted yield load calculated by Larsen's formula proposed by Larsen was 0.80~1.10 at inserted connection, and 0.75~1.46 at side connection. 4. When the inserted bolt connection was based on the yield load of end-distance 7 d, the reduction factor was 0.89 at 12 mm connection, 0.93 at 16 mm and 0.85 at 20 mm. The reduction factor was 0.89 at 12 mm the inserted drift-pin connection, 0.93 at 16 mm, 0.93 at 20 mm. The reduction factor was 0.79 at the side connection of the 12 mm bolt connection and 0.80 at 16 mm.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.604-607
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• 2002

In this study, we will try to develop the 3D automatic design program of limit gauge. When users, who have some mechanical information, input some date, they can do 3D-modeling easily like expert. This is one of the merit in automatic design program and the automatic design program can compare the limit gauge made in this study with processed the bolt and nut model. This demonstrates the effective value of automatic design model. Limits gauge of sort divide into ring gauge of measuring bolt and pin gauge of measuring nut. The new automatic design program follows the KS.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.12a
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• pp.493-505
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• 1999

Zoom lens camera calibration is an important and difficult problem for two reason at least. First, the intrinsic parameters of such a camera change over time, it is difficult to calibration them on-line. Secondly, the pin-hole model for single lens system can not be applied directly to a zoom lens system. In this paper, We address some aspects of this problem.

• Journal of Sensor Science and Technology
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• v.17 no.4
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• pp.273-280
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• 2008

Monolith aperture-type oxygen sensors with simple structure of YSZ(pin-hole)/Pt/ YSZ(solid electrolyte)/Pt were fabricated by co-firing technique. To enhance the yield of productivity, a couple of YSZ green sheets for diffused barrier and solid electrolyte were prepared by tape-casting and co-firing method. The limit current characteristics of the oxygen sensors were measured between 500 and $650^{\circ}C$ The heating temperature of $600^{\circ}C$ was optimum as a portable oxygen sensor in the range of oxygen concentration from 0 to 75 vol%. Linear proficiency of limit current behavior as a function of oxygen concentration was controlled by the variation of aperture dimension. The fabricated oxygen sensors showed the stable sensing output for 30 days. Gas leakage in bonding area due to warping, cracking and thermal cycling was not found in the period.