• 대한토목학회논문집
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• 제34권2호
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• pp.573-582
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• 2014

교차로에 인접한 부 도로에 대한 설치기준이 명확하지 않아 설치 및 운영에 많은 문제점을 야기시키고 있으며, 이로 인하여 교통소통과 교통안전에 문제가 발생하고 있다. 현재까지 교차로 진출입과 관련하여 운영적인 측면에서는 많은 연구가 시도되었지만, 교차로에 인접한 부 도로에 대한 연구는 대단히 미흡하고 이에 따른 합리적인 설계가 이루어지지 못하는 실정이다. 이에 본 연구에서는 교차로에 인접한 부 도로에서 진출하는 차량에 대한 행태를 조사하고, 교통소통과 안전을 고려하여 교차로에 인접한 부 도로의 적절한 이격거리를 제시하고자 한다. 교통소통과 안전을 도모할 수 있는 교차로에 인접한 부 도로의 적정길이를 제시함으로써, 향후 교차로에 인접한 부 도로와과 관련된 설치기준 정립에 이바지하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1375-1377
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• 1995

This paper describes characteristic of ozone Generation by positive streamer corona discharge. Experiments were carried out with needle-plane Electrodes in a pyrex glass tube, in order to in crease the ozone yield. The results of Experiments confirmed needle an gle $45^{\circ}$ Gap spacing 15mm is adaptive Electrode arrangement.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.153-156
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• 1999

In this paper, a plate type ozonizer has been designed and manufactured to minimize the size of ozonizer. This ozonizer have following benefits : \circled1 convenience of shift and installation \circled2 maximize space utility. Therefore, ozone generation characteristics have been investigated by varying flow rate, supplied voltage and gap spacing of plate electrodes.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.205-208
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• 2000

In this paper, a plate type ozonizer has been designed and manufactured to minimize the size of ozonizer. This ozonizer have following benefits: convenience of shift and installation maximize space utility. Therefore, ozone generation characteristics have been investigated by varying flow rate, supplied power and gap spacing of plate electrodes.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2001년도 학술대회논문집
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• pp.135-138
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• 2001

Recently, ozone is utilized In various fields and its needs are expanding. therefore, so many ozone generation methods have been reported in the latest years, its main purpose Is to get the high ozone concentration and to improve the ozone yield. One of them is a plate-type ozone generator. In this paper, the plate-type ozone generator is piled up many folds(3 and 5 electrodes). Ozone concentration and yield were investigated in accordance with power, quantity of supplied gas and gap spacing of plate electrodes.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.85-90
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• 2007

Aerodynamically generated noise is significant when the train speed exceeds 250km/h. Experiments were performed in order to investigate the characteristics of aerodynamic noise sources generated from exterior of the HSR-350x, especially from the inter-coach spacing. Measurements of both the inside and outside of the cabin are carried out to investigate the characteristics of the noise. Effect of the size of the gap has been investigated through an wind tunnel test and it has been found that the low frequency noise is strongly dependent on the size of gap. Also performed is an array measurement to locate different noise sources from the high-speed train. Spectral characteristics of exterior noise sources have been examined through these experiments.

• 한국소음진동공학회논문집
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• 제23권2호
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• pp.167-175
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• 2013

The wave propagation characteristics of an acoustic metamaterial composed of periodically repeated one-dimensional Helmholtz resonator array was investigated considering the effects of dimensional changes of the resonator geometry on the transmission coefficient and band gap. The effective impedance and transmission coefficient of the acoustic metamaterials are obtained based on the acoustic transmission line method. The designed acoustic metamaterials exhibit band gaps and negative bulk modulus that are non-existent properties in the nature. The band gap of the acoustic metamaterial is strongly dependent on the geometry parameters of Helmholtz resonators and lattice spacing. Also, a new type of metamaterial that is periodically constructed with two different resonators was designed to open the local resonance band gap without change of Bragg scattering.

• 대한기계학회논문집B
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• 제33권7호
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• pp.495-505
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• 2009

A two-dimensional circular cylinder freely falling in a channel has been simulated by using immersed boundary - lattice Boltzmann method (IB-LBM) in order to analyze the characteristics of motion originated by the interaction between the fluid flow and the cylinder. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the transverse force and the trajectory in the streamwise and transverse directions. In addition, the effect of the gap between the cylinder and the wall on the motion of a two-dimensional freely falling circular cylinder has been revealed by taking into account a various range of the gap size. As the cylinder is close to the wall at the initial dropping position, vortex shedding in the wake occurs early since the shear flow formed in the spacing between the cylinder and the wall drives flow instabilities from the initial stage of freely falling. In order to consider the characteristics of transverse motion of the cylinder in the initial stage of freely falling, quantitative information about the cylinder motion variables such as the transverse force, trajectory and settling time has been investigate.

• 한국철도학회논문집
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• 제10권6호
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• pp.786-791
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• 2007

고속열차의 속도가 300km/h 이상이 되면 난류의 박리나 와류발산 등에 의한 공력소음의 영향이 지배적이 된다. 본 연구에서는 KTX와 한국형고속열차의 외부에서 발생하는 공력소음, 특히 차간 공간에서 발생하는 소음의 특성을 시험을 통해 규명한다. 차량 실내외의 소음 측정을 통해 이 소음의 특성을 분석하였고, 풍동시험을 통해 머드플랩 사이의 틈의 크기가 저주파 소음 발생에 직접적인 영향을 준다는 것을 규명하였다. 또한 마이크로폰어에이 시험으로 고속열차의 외부에서 발생하는 소음의 주파수 특성을 분석하였다.

• 대한기계학회논문집B
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• 제27권7호
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• pp.909-919
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• 2003

Two-dimensional flow over a pair of circular cylinders in a side-by-side arrangement at low Reynolds numbers has been numerically investigated in this study Numerical simulations are performed, using the immersed boundary method, for the ranges of 40$\leq$Re$\leq$160 and $g^{*}$＜5, where Re and $g^{*}$ are, respectively, the Reynolds number and the spacing between the two cylinder surfaces divided by the cylinder diameter. Results show that a total of six kinds of wake patterns are observed over the ranges: antiphase-synchronized, inphase-synchronized, flip-flopping, single bluff-body, deflected, and steady wake patterns. It is found that the characteristics of the flow significantly depends both on the Reynolds number and gap spacing, with the latter much stronger than the former. Instantaneous flow fields, time traces, flow statistics and so on are presented to identify the wake patterns and then to understand the underlying mechanism. Moreover, the bifurcation phenomenon where either of two wake patterns can occur is found at certain flow conditions.ons.