• 한국환경과학회지
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• 제23권7호
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• pp.1349-1358
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• 2014

This study suggests plan of green space management based on the result of research apprehending the characteristic through sorting types of city thermal environment targeting summer which thermal pollution is the most serious. Considering anthropogenic heat, development level of wind road, thermal environment, as a result of types of thermal environment process, it is appeared 36 types, and 10 types is relevant of this research subject. Type I-1, size of building is large, artificial covering area is wide, and thermal load of anthropogenic heat is high, type II-1, development condition of wind road is incomplete as IIlevel, entering cold air is difficult and thermal management and improvement is needed area. Type III-1, scale is large and it is area of origin of cold air, development level of wind road is mostly favorable, type III-2 is revealed as smaller scale than III-1, and small area of origin of cold air. Type IV, anthropogenic heat is $81{\sim}150W/m^2$, average, but development function of wind road is very favorable. Type V, large area of thermal load and the origin of cold air are distributed as similar ratio, and level of development function of wind road is revealed as II level. According to standard of type classification of thermal environment, as a result of suggesting plan of green space management and biotops area ratio, type I-1 is buffer green space and waterway creation, goal biotops area ratio 35%, type II-1 afforestation in site and goal biotops area ratio 40%, type III-1, preservation plan to display the current function continuously is requested. Type IV suggests afforestation of stream current, and type V suggests quantitative increase of green space and goal biotops area ratio 45%.

• 환경영향평가
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• 제27권4호
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• pp.394-401
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• 2018

본 연구는 환경영향평가의 생태면적률의 인구, 지역, 사업 유형, 총 사업면적에 따른 경향성을 분석하였다. 생태면적률은 총대지면적 중 생태적 기능이 있는 토지면적의 비율로, 생태계 보존과 개발된 단지에서 생활하는 시민들의 건강과 삶의 질에 중요한 요소이다. 현재 환경영향평가에서는 가중치가 고려된 생태면적과 총 사업면적의 비로 생태면적률을 산출하며, 각 사업 유형 별로 최소 목표 생태면적률을 제시하여 최소한의 생태면적을 확보하도록 하고 있다. 경향성에 대한 평가는 도시의 개발, 산업입지 및 산업단지 조성, 관광단지 개발, 폐기물처리시설 및 분뇨처리시설의 설치 사업 등 총 4가지 사업에 대하여 총 55개의 표본을 근거로 하였다. 본 연구는 경향성을 분석한 결과 인구에 대한 고려가 반영된 척도, 사업빈도와 지역 전체를 고려한 생태면적률 조정, 그리고 최소달성치 달성 여부에 대한 규제 강화를 통해 현 제도를 개선해야 한다는 결론을 얻었다. 본 연구 이후로 더 많은 수의 데이터를 포함한 광범위한 연구와, 구체적 제도개선에 대한 연구가 후속되어야 한다.

• Journal of Ginseng Research
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• 제8권2호
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• pp.178-183
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• 1984

This study was conducted to know the influence of plant age and cultural conditions such as plant population density and light intensity under the shading on the leaf shape of panax ginseng. The result obtained were as follows; 1) Leaf length(L)/maximum width(W) was no difference with different age of over 3-over 3year old plant, but that of 1 or 2-yearold was smaller than those of over 3-year old. The values of L/W showed in the order of 2 or 4,3, 1 or 5 leaflet. 2) Ratios of leaflet area to leaf area were 32.0% in leaflet 3, from 209.% to 27.9% in leaflet 2 or 4, and from 6.5% to 7.1% in leaflet 1 or 5. 3) The coefficients of variability for L/W and ratio of leaflet area to leaf area of leaflet 3 were smallest among leaflets. 4) There were significant differences between largest and smallest leaflet 3, leaf areas and ratio of leaflet 3 area to leaf area in same plant. 5) LW and ratio of leaflet 3 area to leaf area were not affected by plant population density. 6) It showed a tendency that the L/W was increased with increasing the light transmittance rate (LTR). The ratio of leaflet 3 area to leaf area of ginseng grown under 20% LTR was not different comparing to that of plant grown under 5% LTR, but it was significantly increased in plant grown at 100% LTR.

• 대한기계학회논문집B
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• 제24권1호
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• pp.132-142
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• 2000

The objective of this study is to experimentally investigate the noise propagating characteristics, the noise reduction mechanism and the performance of a slotted tube attached at the exit plane of a circular convergent nozzle. The experiment is performed through the systematic change of the jet pressure ratio and the slot length under the condition of two kinds of open area ratios, 25% and 51%. The open area ratio calculated by the tube length equivalent for the slot length is defined as the ratio of the total slot area to the surface area of a slotted tube. The experimental results for the near and far field sound, the visualization of jet structures and the static pressure distributions in the jet passing through a slotted tube are presented and explained in comparison with those for a simple tube. The propagating characteristics of supersonic jet noises from the slotted tube is closely connected with the slot length rather than the open area ratio, and its propagating pattern is similar to the simple tube. It is shown that the slotted tube has a good performance to suppress the shock-associated noise as well as the turbulent mixing noise in the range of a limited jet pressure and slot dimension. The considerable suppression of the shock‘associated noise is mainly due to the pressure relief caused by the high-speed jets passing through the slots on the tube. Both the strength of shock waves and the interval between them in a jet plume are decreased by the pressure relief. Moreover, the pressure relief is divided into the gradual and the sudden relief depending upon the open area ratio of the slotted tube. Consequently, the shock waves in a jet plume are also changed by the type of pressure relief. The gradual pressure relief caused by the slotted tube with the open area ratio 25% generates the weak oblique shock waves. On the contrary, the weak normal shock waves appear due to the sudden pressure relief caused by the slotted tube with the open area ratio 51%.

• 한국농공학회지
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• 제44권7호
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• pp.64-73
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• 2002

This study was performed to evaluate effects of physical characteristics of both watershed and reservoir on nutrient-chlorophyll relationship in Korean reservoirs. Simple linear models were developed with published data in Korea including 415 reservoirs and 11 multi-purpose dams, and physico-chemical parameters of reservoirs and characteristics relationship of models were analyzed. Theoretical residence time in Korean reservoirs was strongly correlated with the ratio of TA/ST (drainage area + surface area / storage volume) in the logarithmic function. As a result of monthly nutrients-chlorophyll-a regression analysis, significant Chl-a-TP relationship appeared during May～July. The high Chl-a yields per total phosphorus appeared during this time (R$\^$2/=0.51, p<0.001, N= 1088). Chlorophyll-a demonstrated much stronger relationship with TP. than TN. Seasonal algal-nutrient coupling were closely related with N:P ratio in the reservoir water, and it was, in turn, dependent on the monsoon climatic condition (precipitation). Based on the results of regression analysis and high N:P ratio, a major limiting factor of algal growth appeared to be phosphorus during this time. Unlikely TA/ST ratio, DA/SA ratio (drainage area f surface area) was likely to influence directly on the nutrient-Chl-a relationship, indicating that if storage volume and inflowing water volume were the same, algal biomass could be developed more in reservoirs with large surface area. Thus, DA/SA ratio seemed to be an important factor to affect the development of algal biomass in Korean reservoirs. With low determination coefficient of TP-Chl-a relationship, our findings indicated not only nutrient (phosphorus) but also other physical factors, such as DA/SA ratio, may affect algal biomass development in Korean reservoirs, where actual residence time appears to be more closely related to reservoir surface area rather than storage volume.

• 한국해양공학회지
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• 제33권6호
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• pp.597-606
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• 2019

Due to climate change, coastal areas are being flooded with torrential rain, typhoons, and tsunamis. In addition, non-point source pollutants (NPSs) that accumulated on the ground, streets, and buildings during the dry season are washed off by rain and stormwater runoff, which adds to the damage associated with environmental pollution, e.g., pollution that makes its way into the ocean. Recently, low impact development (LID) has been considered as a means of controlling water circulation and NPSs. In the coastal area, permeable blocks have been constructed mainly to reduce the flood damage caused by waves. Some important design factors that must be considered to ensure long-term performance are the permeability coefficient, clogging, and the efficiency of the removal of total suspended solids (TSS), but currently there are no standardized design criteria or testing techniques that are used worldwide. Herein, we analyzed the permeability coefficient and the TSS removal efficiency tendency according to the permeability area ratio with an easily-detachable, permeable block filled with calcinated yellow soils as the filter media. Our lab-scale tests indicated that, when the permeability area ratio was 25%, the reduction of the permeability coefficient after clogged was 11%, which was a significant decrease compared to other cases. Permeability persistence increased when the permeability area ratio increased from 50% to 75%. The TSS removal efficiency decreased as the permeability area ratio increased. Our pilot-scale test indicated that the TSS removal efficiency was more than 80% higher in all cases. We also found that the permeability persistence was excellent as the permeability area ratio increased, and, in actual construction, it is effective to set 5.3% of the total area as permeable area in terms of permeability and economic feasibility.

• 지역사회간호학회지
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• 제14권2호
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• pp.263-273
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• 2003

Objectives: The purpose of this study was to identify the family phenomenon and characteristics by ICNP such as family shape, life standard. area, and development stage. Method: 1. Sample size was 115. 2. Data analysis method included frequency analysis including ratio. Results: 1. On the distribution of the family phenomena by family shape, the nuclear family showed a higher ratio on the distribution in family communication and the unhealthy life style. The nuclear family was related to children andhad a higher ratio on the inadequate care management of the sick member. The extended family showed the highest ratio on the inadequate care management of sick member. 2. On the distribution of the family phenomena by family life standard, the family with medium life standard showed a higher ratio on the inappropriate family coping, whereas the family with lower life standard appeared to have a higher ratio on the inadequate care management of the sick member. 3. On the distribution of the family phenomena by area. the large city area showed the highest ratio on the inappropriate family coping, the medium and small city area appeared to have the highest ratio on the unhealthy life style. The county area showed the highest ratio on the inadequate care management of sick member. 4. On the distribution of the family phenomena by development stage, the family in rearing period showed a higher ratio on the inappropriate family coping and the lack of family intimacy. Families with preschool children showed a higher ratio on the unhealthy life style, and families with school age children showed the highest ratio on the inappropriate family coping. Families with adolescents appeared to have the highest ratio on the disturbance in family communication, and families with launching young adults showed the highest ratio on the inadequate care management of sick member. 5. On the distribution of the family characteristics by family shape, the nuclear family showed a higher ratio on the family characteristics such as less communication chances among family members and neglect of general child rearing, whereas the third generation family appeared to have a higher ratio on the characteristics such as overburden of housewife's role and short of caring among family members. 6. On the distribution of the family characteristics by family life standard, the family of medium life standard showed higher ratio on the family characteristics such as a few communication chance among family and overburden of housewife's role, and the family of lower life standard appeared to higher ratio on the family characteristics such as short of caring among family members. 7. On the distribution of the family characteristics by area. the large city area showed a higher ratio on the family characteristics such as overburden of housewife's role and neglect of general child rearing. The medium and small city area appeared to have a higher ratio on the family characteristics such as less communication chancec among family members. The county area showed a higher ratio on the family characteristics such as short-term care among family members. 8. On the distribution of the family characteristics by development stage, the family with rearing period showed a higher ratio on the family characteristics such as neglect of general child rearing. Families with preschool children showed a higher ratio on the family characteristics such as less communication chancec among family members. Families with school age children showed a higher ratio on the family characteristics such as overburden of housewife's role. Families with adolescents appeared to have a higher ratio on the family characteristics such as less communication chances among family members. Families with launching young adults showed a higher ratio on the family characteristics such as less communication chances and short-term care among family members.

• 한국지반공학회논문집
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• 제16권4호
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• pp.117-128
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• 2000

모래다짐말뚝(SCP)공법은 느슨한 모래지반이나 연약한 점성토지반을 압밀촉진시키고 지지력을 강화하여 지반을 개량할 목적으로 적용되는 개량공법이다. 이 연구에서는 연약지반개량을 위해 점토지반에 모래다짐말뚝을 사용하는 경우에 지반개량목적에 부합되는 적절한 치환율($a_s$)을 결정하기 위해 치환율 변화에 따른 모형토조시험과 대형직접전단시험을 실시하였다. 원형모형토조를 이용한 실내시험에서는 20%, 30%, 40%, 50%, 60% 의 치환율로 모래다짐말뚝을 조성하여 모래다짐말뚝의 치환율과 복합지반의 응력분담비, 침하저감효과의 한계를 규명하였다. 또한, 대형직접전단시험기를 이용하여 치환율 20%, 30%, 46% 의 복합지반에 대하여 치환율이 복합지반 강도에 미치는 영향도 조사하였다.

• 한국초지조사료학회지
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• 제12권4호
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• pp.226-231
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• 1992

This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.121-125
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• 2007

LCVA has an advantage that its natural frequency can be easily controlled by changing the area ratio of the vertical column and horizontal part. The previous studies investigated the dynamic characteristics of the LCVA under harmonic load. This study experimentally obtained the first and second mode natural frequencies of the LCVA from shaking table tests using white noise and compared the values with the ones by previous study. Test results show that the measured first mode natural frequency of the LCVA is larger than the calculated one when the area ratio is larger than 1. The second mode frequency increases with the increasing area ratio, which is due to the sloshing motion effect resulting from the large area of the vertical column.