• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 사면안정 학술발표회
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• pp.139-151
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• 2000

Rockfall protection fence is one of the most common rockfall protection measures in Korea. The fences have been constructed in almost every hazardous cutslopes along national highway in Korea. However, the capability and performance of the fence as rockfall protection system are seldom known since no field test which can provide information on the response and the behavior of fence was carried out. This is the first full scaled rockfall test in Korea. The objectives of the test are to provide the information on the behavior and the capability of fence and to propose the design specifications for the fence. In this test, four different systems have been selected and tested. For each test, the rockfall impact energy was analyzed and the response and behavior of the system were investigated.

• 대한기계학회논문집B
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• 제24권9호
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• pp.1175-1184
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• 2000

Effects of porous wind fences on the wind erosion of particles from a triangular sand pile were investigated experimentally. The porous fence and sand pile were installed in a simulated atmospheric boundary layer. The mean velocity and turbulent intensity profiles measured at the sand pile location were well fitted to the atmospheric boundary layer over the open terrain. Flow visualization was carried out to investigate the motion of windblown sand particles qualitatively. In addition, the threshold velocity were measured using a light sensitive video camera with varying the particle size, fence porosity $\varepsilon$ and the height of sand pile. As a result, various types of particle motion were observed according to the fence porosity. The porous wind fence having porosity $\varepsilon$=30% was revealed to have the maximum threshold velocity, indicating good shelter effect for abating windblown dust particles. With increasing the sand particle diamter, the threshold velocity was also increased. When the height of sand pile is lower than the fence height, threshold velocity is enhanced.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.153-162
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• 2005

The structural specification of the rockfall prevention fence installed on the road section is computed according to the hypothetic rockfall energy, and the absorbable energy of the rockfall prevention fence is defined as the sum of the absorption energies of the wire rope, one of the components, the steel support and the wire netting. But the results of the field tests confirmed that the absorption energy of the rockfall prevention fence is not the sum of the energies sustainable by the components, but it is affected by the absorbable energy of part of the components. This shows there are problems with the method of computing the absorption energy of the rockfall prevention fence of the road. So in this paper, as a way of solving the problems, the effects of improving the performance through positional changes of the existing components and the effects of improving the performance through structural changes by expanded metal are checked through tests, and a plan was proposed to solve the problems with the standards of installing the conventional rockfall prevention fence.

• 대한기계학회논문집B
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• 제23권10호
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• pp.1340-1346
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• 1999

The turbulent shear flow around a surface-mounted vertical fence was investigated using the two-frame PTV system. The Reynolds number based on the fence height(H) was 2950. From this study, it is revealed that at least 400 instantaneous velocity field data are required for ensemble average to get reliable turbulence statistics, but only 100 field data are sufficient for the time-averaged mean velocity information. Various turbulence statistics such as turbulent intensities, turbulence kinetic energy and Reynolds shear stress were calculated from 700 instantaneous velocity vector fields. The fence flow has an unsteady recirculation region behind the fence, followed by a slow relaxation to the flat-plate boundary layer flow. The time-averaged reattachment length estimated from the streamline distribution is about 11.2H. There exists a region of negative Reynolds shear stress near the fence top due to the highly convex (stabilizing) streamline-curvature of the upstream flow. The large eddy structure in the separated shear layer seems to have significant influence on the development of the separated shear layer and the reattachment process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.279-281
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• 1997

The properties of Platinum dry etching were investigated in MICP(Magnetized Inductively Coupled Plasma). The problem with Platinum etching is the redeposition of sputtered Platinum on the sidewall. Because of the redeposits on the sidewall, the etching of patterned Platinum structure produce feature sizes that exceed the original dimension of the PR size and the etch profile has needle-like shape.[1] Generally, $Cl_2$ plasma is used for the fence-free etching.[1][2][3] The main object of this study was to investigate a new process technology for the fence-free Pt etching. Platinum was etched with Ar plasma at the cryogenic temperature and with Ar/$SF_6$ plasma at room temperature. In cryogenic etching, the height of fence was reduced to 20% at $-190^{\circ}C$ compared with that of room temp., but the etch profile was not fence-free. In Ar/$SF_6$ Plasma, chemical reaction took part in etching process. The trend of properties of Ar/$SF_6$ Plasma etching is similar to that of $Cl_2$ Plasma etching. Fence-free etching was possible, but PR selectivity was very low. A new gas chemistry for fence-free Platinum etching was proposed in this study.

• 한국환경복원기술학회지
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• 제10권2호
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• pp.26-33
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• 2007

This study was to investigate the reaction analysis of citizen on fence removal for securing green space. The results are as following; The majority of users went to green space more than one time per week to take a walk, rest and stayed there less than an hour. The places, where the fence removal was required mostly, were public institutions, parks and schools. The physical factor was the highest influence on whether the fence removal project could be expanded or not. With a slight difference from the physical factor, the environmental and emotional factor followed after. The social factor was also significant at 1 % level. In the physical aspect, the increase of garbage littering was the most negative part after fence removal.When the citizens were asked if they would participate in the fence removal project, the environmental and emotional factor and the social factor were the most influential ones on work places while the environmental and emotional factor influenced only on private houses.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 춘계 학술대회논문집
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• pp.155-161
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• 1999

The three-dimensional turbulent cascade flows with and without endwall fences are numerically investigated by solving the incompressible Navier-Stokes equations with a high-Reynolds number $k-{\varepsilon}$ turbulence closure model. A projection method based algorithm is used in the finite-volume formulation, with the second order upwind-differencing scheme for the convective terms. First, assessments on accuracy of the present method are made by comparing the static pressure distributions at the mid-span of the cascade with measured data, and also by confirming the experimental observations on the choice of an optimal fence height for the secondary flow control. In understanding the three-dimensional nature of the secondary flow in turbine cascade, the limiting streamline patterns and the static pressure contours at the suction surface of the blade as well as on the cascade endwall are employed to visualize the effectiveness of the endwall fence for the secondary flow control. Analysis on the streamwise vorticity contour maps along the cascade with the three-dimensional representation of their iso-surfaces reveals the strucuture of the complicated vortical flow in the turbine cascade with endwall fence, and also leads to an understanding on formation of the counter-rotating streamwise vortex over the endwall fence, in explaining the mechanisms of controlling the secondary flow and also for the proper selection of an optimal fence height.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.523-530
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• 2002

Recently, while rockfall occurs very frequently, a lot of researches on the rockfall protection fence Is in process. But the rockfall protection fence has been installed unrelated to slope characteristics, rockfall shape and rockfall height. Therefore, in this study we suggested the effective protection fence model considering about rockfall energy and energy absorbing capacity and we verified the model by field test. According to these results, it is more reasonable to evaluate rockfall energy based on the results of simulation program, which can be consider effects of energy decrease, than use the simplified method proposed by Japanese road association. And rockfall energy is affected by the size of supports and wire rope and the space of supports. As the results of comparing rockfall energy with energy absorbing capacity, type$\circled1$(the space of supports is changed to 3.0m)can be available for generally expected rockfall except the rock slope over 30m heights. But rockfall protection fence installed at the field, it should be partially reinforced after consideration of slope particularities and construction conditions.

• 한국전자통신학회논문지
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• 제14권2호
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• pp.275-282
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• 2019

산이나 건물과 같은 지형지물에 의해 발생하는 클러터는 대기 상태와 무관한 오염된 자료로 간주된다. 클러터 신호를 줄이기 위한 기본적인 방법은 윈드프로파일러 주위에 클러터 펜스를 설치하는 것이다. 클러터 펜스가 윈드프로파일러 관측 자료에 미치는 효과를 조사하기 위해 클러터 펜스 설치 전과 후의 윈드프로파일러 바람 벡터 수집률과 바람 벡터의 정확도를 고도별로 조사하였다. 윈드프로파일러의 클러터 펜스는 자료 수집률 뿐만 아니라 자료의 품질을 향상시키는데 기여하였다.

• 생태와환경
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• 제36권4호통권105호
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• pp.467-472
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• 2003

본 연구에서는 상수원수 취수장의 취수구로 유입되는 조류 군체의 양을 물리적으로 억제할 수 있는 조류 펜스를 개발하고, 현장에 적용 및 평가하였다(2001년 6-9월). 펜스를 설치한 후 펜스 안팎의 식물플랑크톤 생체량은 통계적으로 유의한 차이를 나타내었다. 분산 분석의 결과 설치 1일 후의 chl. a는 모든 수심 (0, 1,2 m)에서 유의한 차이를 보였으며 (모든 수심에서 0.001 > p ,각 수심별 r= 16), 특히 표층과 수심 1m에서 가장 큰 차이를 보였다. 하지만 조류 저감 효과는 설치 후 3-5일이 지나면서 감소하였다. 조류 펜스의 물리적 유입 저감 효과의 지속성 유지를 위해서는 효과적인 설치 및 유지관리 방안(예, 기계적인 설치 및 주기적인 역세척 등)이 모색되어야 하며, 생태 모형을 이용하여 대번성 시기 예측이 가능할 경우 훨씬 효과적으로 조류의 유입 차단이 가능할 것으로 보인다.