• Geomechanics and Engineering
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• 제16권2호
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• pp.151-157
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• 2018

The constrained conditions of roof and floor for the coal pillar affect the strength of coal pillar very seriously. To analyze the influence of rock mass for the roof and floor on the stability of coal pillar comprehensively, one method based on the mechanical method for the composite rock mass was proposed. In this method, the three rock layers of roof, floor and coal pillar are taken as the bedded composite rock mass. And the influence of rock mass for the roof and floor on the elastic core of coal pillar has been analyzed. This method can obtain not only the derived stress by the cohesive constraining forces for the coal pillar, but also the derived stress for the rock mass of the roof and floor. Moreover, the effect of different mechanical parameters for the roof and floor on the stability of coal pillar have been analyzed systematically. This method can not only analyze the stability of strip coal pillar, but also analyze the stability of other mining pillars whose stress distribution is similar with that of the strip coal pillar.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문 발표회
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• pp.97-101
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• 2003

Currently, it is increasing the importance of floor impact sound performance in apartment building due to users' various needs for comfortable residential environments. However, there are little date on floor impact sound performance because Korean apartment building floor is an ON-DOL which is made of several elements. In this study, floor impact sound performance according to variation of floor construction method were investigated. And based on these investigated results, datas can be used to supply constructor and comsumer basis data to estimate floor impact sound performance.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.1090-1100
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• 1996

Heating floor is the most profitable system of air heating at poultry houses. THe tubes with heating elements inside are laid into the layer of concrete. To prevent lossese of heat penetration deep into the ground the layer of isolation material is laid below the tubes . The depth of isolation laying in every point of the heating floor may be calculated according to the author's formula using the data of temperature on the floor surface and the tube, the distance between tow nearest tubes, and the distance between the tube and the floor surface. Technological investigations allow to estimate the optimal density for greese and ducks when they are bred on the heatuing floor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.225-226
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• 2014

In multi-story buildings, heavy-weight floor impact noise propagates through multiple layers. In order to evaluate the influence of structural vibration and propagation, the actual twelve-story building was excited by an impact ball. Sound and vibration responses of each floor was measured using accelerometers and a microphone. Vibration characteristics and its transfer paths were different depending on the excitation floor locations due to differences in the structural characteristics. From the measurement result, transfer characteristics were quantified by statistical energy analysis. It was confirmed that the heavy-weight floor impact noise influence not only adjacent floor. The impact noise transferred and affected multiple layers.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.7-9
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• 2014

An auditory experiment was conducted to establish annoyance criteria for floor impact noise in apartment buildings. Heavyweight floor impact sounds were recorded using an impact ball; the impact sound pressure level (SPL) together with the temporal decay rate (DR), which is quantified by the dB drop per second, was analyzed. For the experiment, A-weighted exposure levels of the heavy-weight floor impact sounds ranging 34~73 dB were evaluated at 3 dB intervals. Participants used a 7-point verbal scale to evaluate the level of annoyance from floor impact noise. The results show that the annoyance increases with increasing impact SPL and decreasing DR. Consequently, a classification and an acceptable level of floor impact sounds were proposed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.97-101
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• 2003

Currently, it is increasing the importance of floor impact sound performance in apartment building due to users' various needs for comfortable residential environments. However, there are little data on floor impact sound performance because Korean apartment building floor is an ON-DOL which is made of several elements. In this study, floor impact sound performance according to variation of floor construction method were investigated. And based on these investigated results, datas can be used to supply constructor and comsumer basis data to estimate floor impact sound performance

• 설비공학논문집
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• 제14권2호
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• pp.143-152
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• 2002

It is critical for radiant floor cooling system using Ondol to cause condensation on a floor surface. To solve this problem, a radiant floor cooling system integrated with dehumidification was proposed and evaluated in terms of its applicability and prevention of condensation. Therresults show that the proposed system of radiant floor cooling integrated with dehumidification properly maintained the indoor setpoint temperatures and prevented the condensation on a floor surface. To achieve more stable indoor temperatures and humidity control, a further study for the operation of dehumidification panel will be needed.

• 설비공학논문집
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• 제13권6호
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• pp.541-548
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• 2001

The objective of this study is to analyze the possibilities and considerations for the application of the radiant floor cooling system by analyzing the problems of a conventional cooling system through field tests and thermal performance simulations of the radiant floor cooling in an apartment building. The results are as follows. (1) Problems of he conventional cooling system with PAC()packaged air conditioner)'s include draft, local discomfort, and excessive electrical peak demand. (2) According to the measurement during the cooling and intermediate seasons, the floor surface temperatures which are experienced at the time of cooling with PAC\`s and during intermediate season are similar to the temperatures for radiant floor cooling. (3) The radiant floor cooling system is applicable to apartment buildings during the cooling season, especially on hot and clear days.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.305-309
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• 2006

In this paper vibration reduction characteristics of floating floors used in railway vehicles are studied. Vibration reduction characteristics are compared through a series of tests for elastically-coupled floor and rigidly-coupled floor. It was found that elastically-coupled floor has larger vibration reduction amount than rigidly-coupled floor. Around the fundamental natural frequency, however, elastic floor has poor vibration reduction effect than rigid floor. Measures to reduce structure-borne noise are also discussed based on the test results. Structure-borne noise for running railway vehicles cannot be reduced by an effort to deviate resonance between natural frequency of floors and major exciting forces. Instead, reducing vibration level of top floor and using covers which have low sound radiation coefficient will be effective for reducing structure-borne noise.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2002년도 추계학술발표대회
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• pp.237-332
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• 2002

We constructed ceiling structure and floor structure for elevation of sound insulation performance of concrete slab of apartment house. And, we wished to measure heavy floor impact sound level and light floor impact sound level of these structure. As the result, light floor impact sound level interception performance of concrete slab was measured by thing that construction work of gypsum baud is important. Heavy floor impact sound level interception performance was measured by thing that it is effective that construct to thickness about 30 millimeters on concrete Slav. It was measured effectively that heavy floor impact sound level interception performance constructs rubber chip to thickness about 30 millimeters on concrete Slav.