• 한국결정성장학회지
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• 제13권4호
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• pp.153-156
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• 2003

Pure and Ethylenediaminetetraacetic acid (EDTA) doped L-arginine phosphate (LAP) single crystals were grown from the aqueous solution by temperature lowering method. The effect of EDTA additive on the solubility and metastable zone width of LAP solution has been investigated. Addition of EDTA has enhanced the metastable zone width of LAP and hence bulk crystals could be grown. The growth rate along the [100] direction increases with EDTA additive. Powder X-ray diffraction and FTIR studies reveal the absence of EDTA in the lattice of LAP, This reveals that the addition of EDTA to LAP doesn't influence the crystallinity. However, the transmittance and NLO properties significantly increase with EDTA additive and hence bulk LAP crystals are useful for laser fusion experiments.

• International Journal of Air-Conditioning and Refrigeration
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• 제12권2호
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• pp.108-112
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• 2004

The purpose of this study is to investigate the characteristics of thermal comfort index and to present the thermal comfort range through regression analyses and experiment in a radiant floor heating system laboratory. The results were compared to the comfort zone of ISO-7730, and the applicability of the thermal comfort index to a radiant floor heating system was studied. On comparing the sedentary posture on the floor to sitting on the chair, the comfort zone and the neutral point of comfort index showed different values. It is considered that the influence of conduction from floor to the human is sufficient. Moreover, we could find a correlation between the thermal sensation votes of subjects, and the comfort indexes were lower than those by calculation.

• 한국주거학회논문집
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• 제14권4호
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• pp.49-56
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• 2003

The object of this study is to analyze the influential factors of characteristics of residential locations by age, and to offer a groundwork that can be utilized to direct setting of residential development and housing policies. The main findings are drawn as follows: First, it determines the age groupings which can describe the distribution pattern of residential location, which is broken down into two social subgroups - the older group aged 50 and over, and the younger group, being our educational target. Second, actuality of our education is to influence residential location. Third, four groups that can describe residential location are abstracted. Fourth, the prime of manhood and old age prime of life have been superior within inner zone, while middle age and those who are obliged to support the older group have been superior around the outer zone.

• 한국환경과학회지
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• 제2권1호
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• pp.21-28
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• 1993

A total of 94 taxa were identified from the Southern Ocean, 140-148 。E and 40-53。S, as an early austral summer phytoplankton. They were 53 diatoms, 37 dinoflagellates, 2 silicoflagellates, 1 prymnesiophyte, and 1 coccolithophorid. Integrated cell numbers of nanoplankton dominated microphytoplankton from 8 stations, especially from Subantarctic zone, but integrated biomass was lower than microphytoplankton. Integrated cell numbers of diatoms dominated dinoflagellates, coccolithophorids, and pnrnnesiophyte, but integrated biomass of microphytoplankton were dependent to the biomass of dinoflagellates except north of the Subtropical convergence zone and south of the Antractic convergence sone. Phytoplankton community changed across the fronts and 3 different communities were observed. Fronts seem to influence on the phytoplankton community from the west Pacific Sector of the Southern Ocean.

• 터널과지하공간
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• 제4권2호
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• pp.102-118
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• 1994

Thermomechanical analysis is conducted on the radioactive repository in deep rock mass considering the in-situ stress, excavation and thermal loading of a radioactive waste. Thermomechanical properties of a discontinuous rock mass are estimated by a theoretical method so called sequential analysis. Using the estimated properties as input for finite element analysis, the influence on temperature distribution and thermal stress is analyzed within the scope of 2-dimensional steady state and transient heat transfer and coupled thermal elastic plastic behaviour. Granitic rock mass is taken for this analysis. The analysis is done for two different rock mass conditions, i.e. continuous-homogeneous and highly jointed conditions, for the purpose of comparison. In the case of steady state, the extent of disturbed zone around the storage tunnel due to the heat production of the spent-fuel canister varies depending on the thermomechanical properties of the rock mass. In the case of transient analyses, the response of the jointed rock mass to the thermal loading after radioactive waste disposal varies significantly with time, resulting in dramatic changes in the both size and location of disturbed zone.

• Tribology and Lubricants
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• 제16권5호
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• pp.341-350
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• 2000

The study reported in this paper deals with the development for parametric investigation of the influence of the rheological properties of the lubricant in the thermohydrodynamic (THD) film conditions which occur in slider and journal bearings. A parametric investigation based on a Bingham model with a shear yield stress which best fit the experimental pressure is performed for predicting the thickness of the shear Bone in lubricating films with fixed geometry between the stationary and moving surfaces. The results suggest that the shear yield stress for the lubricating film is proportional to the pressure developed in the film within the range of the investigated cases and the shear zone thickness which is of the same order of magnitude as that obtained by the empirical formula is significantly smaller than the fluid film thickness in the lubrication zone.

• Earthquakes and Structures
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• 제17권1호
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• pp.1-15
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• 2019

In the structures with high level of ductility, the earthquake energy dissipation in structural components is an important factor that describes their seismic behavior. Since the connection details play a major role in the ductile behavior of structure, in this paper, the seismic response of 3-, 5- and 8-story steel special moment frames (SMFs) is investigated by considering the effects of panel zone modeling and the influence of forward-directivity near-field ground motions. To provide a reasonable comparison, selected records of both near and far-field are used in the nonlinear time-history analysis of models. The results of the comparison of the median maximum inter-story drift under excitation by near-field (NF) records and the far-field (FF) ground motions show that the inter-story drift demands can be obtained 3.47, 4.86 and 5.92 times in 3-, 5- and 8-story structures, respectively, undergoing near-field earthquakes.

• Geomechanics and Engineering
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• 제17권2호
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• pp.215-225
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• 2019

The mechanical behavior of rock is essential to estimate the capacity and long-term stability of $CO_2$ storage in deep saline aquifers. As the depth of reservoir increases, the pressure and temperature that applied on the rock increase. To answer the question of how the confining pressure and temperature influence the mechanical behavior of reservoir rock, triaxial compression experiments were carried out on brine-saturated sandstone at elevated temperature. The triaxial compressive strength of brine-saturated sandstone was observed to decrease with increasing testing temperature, and the temperature weakening effect in strength enhanced with the increase of confining pressure. Sandstone specimens showed single fracture failures under triaxial compression. Three typical regions around the main fracture were identified: fracture band, damaged zone and undamaged zone. A function was proposed to describe the evolution of acoustic emission count under loading. Finally, the mechanism of elevated temperature causing the reduction of strength of brine-saturated sandstone was discussed.

• 농업과학연구
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• 제12권2호
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• pp.282-291
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• 1985

점사(粘士)대신 화강암질풍화토(花崗岩質風化土)를 성토재료(盛土材料)로 사용(使用)할 경우(境遇) Fill Dam의 침하특성(沈下特性)을 구명(究明)하기 위하여 동재료(同材料)를 사용(使用)한 안동(安東)댐의 매설계기(埋設計器) 측정자료(測定資料)를 분석(分析)하여 얻은 결론(結論)을 요약(要約)하면 다음과 같다. 1. 시공중(施工中) Core zone의 침하(沈下)는 성토재하중(盛土載荷重)이 증가(增加)함에 따라 거의 직선적(直線的)인 증가현상(增加現象)을 보였으며 유효응력(有效應力)이 $7kg/cm^2$ 이하(以下)일 경우(境遇)의 침하율(沈下率)은 0.1~0.8% 범위(範圍)로 일반(一般) 점사(粘士)를 사용(便用)한 Fill Dam에서 보다 작은 값을 나타냈다. 2 하부(下部) Core zone의 침하(沈下)는 성토고(盛土高)의 약(約) 중심부(中心部) 이상(以上)에서 재구(載苟)되는 성토구중(盛土苟重)의 영향(影響)을 크게 받지 않는것으로 나타났다. 3. 간극수압(間隙水壓)은 투수계수(透水係數)가 클수록 저수지(貯水池) 상위(水位) 변화(變化)에 민감(敏感)한 반응(反應)을 보였으며 간극수압(間隙水壓)이 소산(消散)됨에 따라 침하(沈下)는 증가(增加)하는 경향(傾向)을 나타냈다. 4. 성토고(盛土高)의 하부(下部)에서 Zone 간(間)의 침하(沈下)는 상대밀도(相對密度)의 크기에 영향(影響)을 받는것으로 나타났으며 시공후(施工後)에는 압축(壓縮)두께가 큰 Core zone 에서 큰 경향(傾向)을 나타냈다. 5. 댐 정상(頂上)에서의 침하분포(沈下分布)는 댐의 최대단면(最大斷面)인 중심부(中心部)에서 크고 양안(兩岸)으로 갈수록 작게 나타났다.

• 대한교통학회지
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• 제36권2호
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• pp.112-128
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• 2018

국내는 온실가스를 줄이고 보행자 중심의 친환경 도시를 지향하고자 일부지역에 보행자 우선지역을 시행하고 있다. 이는 대중교통 중심의 서비스 개선 및 여유로운 보행공간의 확보 측면에서 시민의 만족도가 높았으며, 친환경 교통수단의 도입으로 온실가스의 감축효과에 기여했다. 그러나 보행자 우선지역은 보행환경 개선 측면에는 영향력이 높지만 주변 교통흐름에는 악영향을 주는 만큼 시행에 따른 교통 환경 변화를 예측할 필요가 있다. 본 연구는 수원시 행궁동 생태교통 지역을 중심으로 보행자 우선도로 시행에 따라 행사주변의 효과를 도출하기 위해 사전사후 평가를 활용한 교통사고 특성변화를 분석하였다. 분석결과 보행자 우선도로는 보행자 중심으로 설계되어 운영되는 만큼 보행자 관련 사고는 줄었으나, 차량의 회전교통 제한에 따른 불법유턴 사고 및 속도 저하에 따른 신호위반 사고가 증가한 것으로 나타났다. 각 지역에는 행사를 시행하기 전 운전자에게 각별한 주의가 요구되며, 행사구역 인근에 본 연구 특성이 반영된 안전표지판 및 어플 정보를 제공하여 교통사고에 유념할 필요가 있겠다.