• 한국환경과학회지
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• 제13권12호
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• pp.1009-1013
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• 2004

The purpose of this study is to select the appropriate wild herbaceous plants on the rooftop. For the purpose of the experiments, 14 wild herbaceous plants were chosen. As the results of the experiments, the wild herbaceous plants growing on the culture soil(perlite) Among the 14 kinds of wild herbaceous plants, such as Chrysanthemum boreale, Taraxacum mongolicum, Aster Koraiensis, Aster yomena, Oenothera odorata, Oenothera lamarckiana, Patrinia scabiosaefolia showed good effects on growth of above ground parts. Therefore, these plants will effective for the rooftop revegetation. Callistephus chinensis and Lotus corniculatus var. Japonicus showed good height growth, wherase covering rate was worst. Chrysanthemum boreale, Platycodon grandiflorum, Patrinia scabiosaefolia were plant height, wherase covering rate was not good . For the expected number of seedings more than 3,000 per square meter, many seedings got withered to death while the survivors were suppressed to grow slow in the early stage due to the densityproblem.

• 한국자원식물학회지
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• 제13권3호
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• pp.208-212
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• 2000

보온 피복재 종류가 자옥 포도 유목의 월동시 동해방지, 노동력 절감 및 병해 발생 억제에 미치는 영향을 구명하기 위하여 11월 하순에 짚을 덮은 다음 보온덮개B, 킬딩, 칼라부직A 및 백색니들펀칭부직포 등을 피복하여 시험한 결과를 요약하면 다음과 같다. 1. 보온력은 백색니들펀칭부직포가 가장 불량하였고, 다른 보온재간에는 차이가 미미하였다. 2. 발아는 보온덮개B에서 빨리 시작되었으며, 발아 9일 후에도 발아율이 79.7%로 타 보온재 보다 2.3∼12.5% 높았다. 3. 생육은 보온재간에 차이가 없었으며, 병해 발생은 킬딩과 보온덮개B에서 뿌리혹병이 지수 3.0∼3.2로 다소 많이 발생되었을 뿐 기타 병해는 처리간에 차이가 없거나 미미 하였다. 4. 작업 단계별 소요노력은 보온덮개B에 비하여 킬딩은 6% 많았으나, 칼라부직A는 6%, 백색니들펀칭 부직포는 15%적었다.

• 아시안잔디학회지
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• 제14권1호
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• pp.251-256
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• 2000

The purpose of this study is to select the appropriate herbicide, which is needed to control the bentgrass in kentucky bluegrass(Poa pratensis) fairway effectively. The best control of bentgrass was observed at /$0.3mL\m^2$ of dithiopyr applied on Kentucky bluegrass. A field experiment was conducted to determine the priming effects on seed germination of Kentucky bluegrass. Ground covering rates by turfgrass were investigated under field conditions for 70 treatments by thirty days after treatment. The solid matrix priming(SMP) treatments on Kentucky bluegrass reduced the number of days requited for emergence and improved final cover ratings. Primed seeds of Kentucky bluegrass (incubated for five days at $20^{\circ}C$) resulted in most rapid germination and covering rate.

• 한국환경보건학회지
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• 제26권3호
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• pp.103-110
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• 2000

This study was conducted from January to December in Kwang-ju city, 1999. Calculated methods were studied by emission factors in each industrial species. The results was that total emission rate of VOC was calculated at a mount of 12305 ton/year as coating(49.4) > vehicles(27.4) > gasoline vapors(6.1) > petroleum refineries(5.6) > graphic arts(4.4) > road covering(4.1) > dry cleang(3.0%) respectively. In vehicles emission rate, passenger car and taxi were about 2,700 ton/yr(60%) of total vehicle emission(3,300 ton/yr). The amount of building emission rate was about 1,900 ton/yr(30%) of total coating emission 6,083 ton/yr.

• 생물환경조절학회지
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• 제20권1호
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• pp.8-13
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• 2011

본 연구는 피복재 종류에 따른 착색단고추의 생육 및 생산성에 대한 지하부 환경 요인의 영향 정도를 알아보았다. 조사 기간 동안 배양액 공급량은 플라스틱 필름온실에서는 $5,404L{\cdot}m^{-2}$로 유리온실의 $3,483L{\cdot}m^{-2}$보다 1.6배나 많았다. 그러나 배양액 흡수율은 두 온실에서 71.3~73.3%로 유사한 수준이었다. 배지 EC도 $4.17{\sim}4.23dS{\cdot}m^{-1}$ 수준으로 큰 차이를 나타내지 않았다. 정단부에서 아래로 6번째 잎의 면적은 유리온실에서 평균 $123.0cm^2$/1eaf로 플라스틱필름온실의 $119.5cm^2$/1eaf보다 다소 넓었다. 그러나 잎의 생체중, 건물중 및 건물률은 두 온실 간 뚜렷한 차이를 나타내지 않았다. 주간 생산량은 유리온실에서 $850g{\cdot}m^{-2}$로 플라스틱필름온실의 $650g{\cdot}m^{-2}$보다 1.3배정도로 많았다. 하지만 조사 기간 동안 잎의 면적 및 건물률, 그리고 생산량 모두에 대한 배지 EC와 배양액 흡수율 차이에서 오는 영향은 두 온실 간 뚜렷한 차이를 나타내지 않았다. 따라서 피복재 및 지상부 환경이 다른 온실에서 착색단고추 수경재배 시 생육 및 생산성 차이에 대한 지하부 요인의 영향은 거의 없는 것으로 판단된다.

• 생물환경조절학회지
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• 제29권1호
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• pp.73-79
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• 2020

본 연구는 일정한 풍환경하에 온실 피복재 관류전열손실을 분석하기 위하여 온실 열손실 분석용 소형 풍동을 제작하고 성능을 분석하였으며 모형온실을 적용하였을 때의 관류전열손실을 분석하였다. 소형 풍동은 시험부 측 공기흐름이 정상상태를 유지하고 편차를 최소화하기 위하여 풍동의 각 요소를 반영하여 구성하였으며 송풍부, 확산부, 정류부, 축소부, 시험부로 구성하였다. 소형 풍동의 형태는 개방형, 토출식으로 결정하였고, 시험부 규격은 제작하고자 하는 모형온실의 규격과 상사비율, 시험부의 단면 폐쇄율을 감안하여 결정하였다. 상사비율을 풍동실험에 적용할 모형은 농업시설 중 가장 큰 비중을 차지하고 있는 단동 비닐온실을 대상으로 하였다. 소형풍동 내 풍속을 조절함에 따라 나타나는 모형온실 피복재의 관류전열계수는 피복재 면을 크게 지붕면과 측벽면, 앞뒷면으로 나누고 각 면별 계측 데이터를 평균 내어 산출하였다. 지붕면은 풍속이 증가함에 따라 전열계수도 증가하나 증가폭이 감소하는 구간은 배치각도에 따라 1-2ms^-1과 2-3ms^-1으로 구분되어지는 것으로 판단되었다. 측벽면의 전열계수가 증가하는 폭이 큰 구간은 0-1ms^-1 구간인 것으로 판단된다.

• 산업기술연구
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• 제21권B호
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• pp.99-105
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• 2001

In this paper, the selective normalized constant modulus algorithm(SNCMA) is applied to a fractionally spaced equalizer. The fractionally spaced equalizer is insensitive to the sampling timing because it processes received signals with the sampling rate larger than the symbol rate. The SNCMA improves the convergence rate by using the large step size for the most outer covering symbol belonging to the trust-level. This blind equalizer exhibits a fast start-up convergence rate as well as a reduced steady-state residual error compared to the fractionally spaced blind equalizer and the T-spaced blind equalizer using conventional blind algorithms.

• Corrosion Science and Technology
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• 제4권5호
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• pp.201-206
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• 2005

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms r-reliability (failure rate) and durability (product life) are explained. The conceptual analysis of failure mechanics explains that reliability technology pertains to design area. The desirable shape of hazard rate curve of electronic items, hockey-stick line, clarifies that Mean-Time-to-failure (MTTF) as the inverse of failure rate can be regarded a nominal life. And Bx life, different from MTTF, is explained. Reliability relationships between components and set products are explained. Reshaped definitions of r-reliability and durability are recommended. The procedure to improve reliability and the reasons for failing to identify failure mode are clarified in order to search right solutions. And generalized Life-Stress failure model is recommended for the calculation of acceleration factor.

• East Asian Economic Review
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• 제17권3호
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• pp.281-310
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• 2013

The aim of this paper is to estimate the degree of RMB misalignment from its equilibrium exchange rate by applying the Behavioral Equilibrium Exchange Rate (BEER) approach. We employ monthly data with reference to China's top 20 trading partners covering the period of 1997 to 2012. We find that the RMB was slightly overvalued before 2001 and significantly undervalued by up to 20 per cent in the end of 2006. There is evidence showing that the RMB approached to its equilibrium level from 2007 to 2008. However, the global financial crisis interrupted the trend of declining misalignment of RMB exchange rate. The RMB's total misalignment increased to around 25 per cent in the mid-2011 mainly because the RMB was re-pegged to the US dollar and some currencies of China's main trading partners depreciated during the period of crisis. More recently, the degree of RMB misalignment slightly declined since 2012 when the RMB proceeded to appreciate and China's ratio of current account surplus to GDP dropped considerably. Our findings prove that there is a trend of the RMB approaching to its equilibrium exchange rate since 2007 except for the period of crisis.

• 소성∙가공
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• 제14권1호
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• pp.65-70
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• 2005

A phase mixture model was employed to simulate the deformation behaviour of metallic materials covering a wide grain size range from micrometer to nanometer scale. In this model a polycrystalline material is treated as a mixture of two phases: grain interior phase whose plastic deformation is governed by dislocation and diffusion mechanisms and grain boundary 'phase' whose plastic flow is controlled by a boundary diffusion mechanism. The main target of this study was the effect of grain size on stress and its strain rate sensitivity as well as on the strain hardening. Conventional Hall-Petch behaviour in coarse grained materials at high strain rates governed by the dislocation glide mechanism was shown to be replaced with inverse Hall-Petch behaviour in ultrafine grained materials at low strain rates, when both phases deform predominantly by diffusion controlled mechanisms. The model predictions are illustrated by examples from literature.