• 한국지리정보학회지
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• 제22권4호
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• pp.197-214
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• 2019

본 연구에서는 Terra/Aqua MODIS LST(Moderate Resolution Imaging Spectroradiometer Land Surface Temperature)의 Daytime, Nighttime 자료와 기상청 기상관측소 86개 지점에 대한 최고, 최저 및 평균기온을 이용하여 두 자료 사이의 상관성을 분석하고, 한파 및 폭염 발생 기간의 특성을 집중적으로 분석하였다. 모든 자료는 2008년부터 2018년까지 총 11년간 일별로 구축하였으며, Pearson 상관계수(Pearson correlation coefficient, R)와 평균제곱근오차(Root Mean Square Error, RMSE)를 이용하여 상관성 분석을 수행하였다. 시계열 분석 결과, 대상 기간 전체에서 기온과 MODIS LST 간의 변동 양상은 유사하였고, 최고 기온과 MODIS 자료의 R 0.9 이상, 평균기온과 최저 기온과는 0.8 이상으로 기온과 MODIS LST 사이의 상관성은 높은 것으로 나타났다. 특히, 최고 기온은 Terra MODIS LST Daytime과 정확도가 제일 높고, 최저 기온은 Terra MODIS LST Nighttime과 상관성이 제일 높은 것으로 분석되었다. 한파 기간에는 Terra/Aqua MODIS 모두 주간 자료보다 야간 자료의 상관성이 더 높은 것으로 분석되었으며, 특히 Terra MODIS LST Nighttime과의 상관성이 좋은 것으로 분석되었다. 폭염 기간에는 Aqua MODIS LST Daytime 자료가 가장 좋은 것으로 분석되었으나, 전체적인 R이 0.5보다 낮아 추후 활용을 위해서는 식생이나 토지이용, 고도 등 다른 요소를 활용한 추가 분석이 필요할 것으로 판단된다.

• Applied Biological Chemistry
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• 제34권2호
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• pp.162-167
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• 1991

식물의 저온 스트레스와 이에 대한 방어체계의 기작론적 측면을 탐색하기 위하여, 냉해유발조건하에서 세워둔 식물(주로 3-4엽기의 벼 유묘)를 대상으로 하여 조직중 pyruvate 함량, superoxide$(O_{\overline{2}})$ 수준 및 항산소성 효소들의 활성을 경시적으로 측정하였다. 저온$(5^{\circ}C)$처리동안에 엽조직에는 현저한 pyruvate축적이 일어났으며, 그 상대적 축적량은 처리시간의 경과에 따라 증가하였다. 그러나 저온처리된 식물을 상온하에 옮겨 놓았을 때 축적된 pyruvate는 곧 소진하기 시작하였으며 이와 동시에 조직내 superoxide$(O_{\overline{2}})$수준이 상승하기 시작하였다. 아울러, 몇시간 정도의 lag time을 가지며 superoxide dismutase(SOD)와 catalase의 활성도 증가하였다. 이에 반하여 또 다른 항산소성 효소인 Glutathione peroxidase는 활성화 현상을 전혀 보이지 않았다. 뿌리를 통해서 외부로부터 공급된 superoxide$(O_{\overline{2}})$는 뿌리 조직내의 SOD와 catalase의 활성을 유도하였다. 한편 $H_2O_2$ 공급이 조직내 catalase는 활성화시켰으나, 역시 glutathione peroxidase에 대해서는 어떤 영향도 미치지 않았다. 위의 모든 결과들은 저온처리중에 일어난 pyruvate의 세포내 축적이 상온으로 환원된 조직내에서 superoxide$(O_{\overline{2}})$ 및 이로부터 이차적으로 생성된 활성산소를 과잉 발생시키는 직접적 원인이라는 사실과, 두 항산소성 효소(SOD와 catalase)가 활성산소를 중간매체로 하여 일어나는 것으로 해석되는 식물냉해로부터 세포를 보호함에 있어서 결정적인 역할을 담당하고 있다는 사실을 강력히 시사하였다.

• 대한물리치료과학회지
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• 제2권3호
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• pp.577-586
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• 1995

This paper was the study of a change in the body temperature of each region(Oral cavity, Axillary, Cubital, Popliteal, Inguinal region)and by time after appling hot(Hot Pack, Infra Red) and cold (Ice Pack, Cooling Pack) to lumbar region. The statistical measures were sampled through 16 senior students in dept. of Physiothrapy, Kim Cheun College and the period for this was from July 13, 1995 to July 20, 1995. There was an increse in the temperature of distal portion besides application area after hot application. The increse in the body temperature according to applied agents and time showed significance statistically(p<0.01, p<0.05). There was just a decrease in the temperature of distal portions besides application area after appling Ice Pack. Furthermore there was an increase in the body temperature after appling Cooling Towel. Therefore, during cold application the appling agents and time did not showed any significance statistically.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.322-326
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• 2010

This study shows that atmospheric TPM concentrations and THg concentrations in precipitation measured in China were higher that those measured in Korea. TPM concentrations and THg concentrations in precipitation during the cold periods were generally higher than those during the warm periods in both China and korea. In China, variations of THg concentration in precipitation during the cold and warm periods were influenced by scavenging of both TPM and RGM. Different from China, in Korea, variations of THg concentration in precipitation during the cold period were also influenced by scavenging of both TPM and RGM; however, those during the warm periods were dominantly governed by scavenging of RGM.

• Steel and Composite Structures
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• 제6권6호
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• pp.513-529
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• 2006

This paper deals with the dynamic behaviour of cold-formed steel hollow frames with different connection stiffnesses. An analytical model of a semi-rigid frame was developed to study the influence of connection stiffnesses on the fundamental frequency and dynamic response of the frames. The flexibilities of the connections are modeled by rotational springs. Neglect of semi-rigidity leads to an artificial stiffening of frames resulting in shorter fundamental period, which in turn results in a significant error in the evaluation of dynamic loads. In the seismic design of structures, of all the principal modes, the fundamental mode of translational vibration is the most critical. Hence, experiments were conducted to study the influence of the connection stiffnesses on the fundamental mode of translational vibration of the steel hollow frames. From the experimental study it was found that the fundamental frequency of the frames lie in the semi-rigid region. From the theoretical investigation it was found that the flexibly connected frames subjected to lateral loads exhibit larger deflection as compared to rigidly connected frames.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.335-340
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• 2000

Most vehicle's exhaust emissions come from the cold transient period of the FTP-75 test. In this study, UEGI technology was developed to help close-coupled catalytic converter (CCC) reach light-off temperature within a few seconds after cold-start. In the UEGI system, unburned exhaust mixture is ignited by four glow plugs installed upstream of the catalyst. Experimental results showed that the temperature of CCC rises faster with the UEGI technology, and the CCC reaches light-off temperature earlier. Under the conditions tested, the light-off time of the baseline case was 62 seconds and that of the UEGI case was 33 seconds.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.132-141
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• 1999

No. 1 PL(Pickling Line) and No. 1 TCM(Tandem Cold Rolling Mill) at Pohang works started up in 1977 and have been operating successfully keeping high productivity for productivity thin gauge sheat such as BP, CR and silicon steel. On the other hand, customer's requirements of quality level are rasing higher continuously, so that Pohang works has combined and revamped No. 1 PL and No. 1 TCM in order to improve labor productivity, thickness accuracy and shape control capability, and so on in the period of 1977∼1999. This paper introduce the applied facilities, technologies and recent operations after revamping.

• 한국자동차공학회논문집
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• 제9권2호
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• pp.43-49
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• 2001

In order to satisfy the ULEV emissions regulation, fast light-off of a catalyst is essential for reduction of HC and CO emissions during the cold start. Cranking Exhaust Gas Ignition(CEGI) method developed in this study showed that the catalyst reaches the light-off temperature in a few seconds. The CEGI stops the ignition signal for a few seconds during the cranking period, so the unburned fuel-air mixture bypasses the combustion chamber and flows through the exhaust manifold. When the unburned mixture reaches two glow plugs installed upstream of the catalyst, it burns and releases the thermal energy to heat up the catalyst, In the FTP-75 vehicle tests, the CEGI showed that the exhaust emissions reduced by 47.7% for THC and by 88.6% for CO in the cold-transient phase of the test.

• Journal of Ginseng Research
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• 제5권1호
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• pp.24-34
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• 1981

For bioassay of the various extracts of ginseng, the growth determination method using Saccharomyces cerevisiae which was cultured with various doses of the extracts, was studied The water extract, Powder. and ethanol extract were more effective (about 45∼ 110% increase) than saponins or its fractions (about 20∼35% increase). The cold methanol residue showed a increase effect but it was not significant. The bioassay curves for the water extract, ethanol extract, the butanol extracted saponins and the cold methanol- residue were made from the experimental data. From these curves it is possible to find the relation between dose and effectiveness and the optimal doses of various ginseng extracts, and the amount of extract in a sample can be estimated The .angers of sample amount were 0.01% (100ppm) ∼0.32% (3200ppm) fo. the water extract, 0.025% (150ppm)∼0.1% (1000ppm) for the ethanol extract, and 0.008% (80ppm)∼0.016% (160ppm) for the saponins. It was impossible to determine the range for the cold methanol- residue, The acceleration effects on the cell proliferation by a only 0.0008% (8ppm) of the diol- and triol-saponin were measurable in earlier Period (24 hour treatment).

• 산업공학
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• 제25권2호
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• pp.153-162
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• 2012

The reliability is defined as a probability that a system will operate properly for a specified period of time under the design operating conditions without failure and it has been considered as one of the major design parameters in the field of industries. Reliability-Redundancy Optimization Problem(RROP) involves selec tion of components with multiple choices and redundancy levels for maximizing system reliability with constraints such as cost, weight, etc. However, in practice both active and cold standby redundancies may be used within a particular system design. Therefore, a redundancy strategy(active, cold standby) for each subsystem in order to maximize system reliability is considered in this study. Due to the nature of RROP, i.e. NP-hard problem, A Parallel Particle Swarm Optimization(PPSO) algorithm is proposed to solve the mathematical programming model and it gives consistently better quality solutions than existing studies for benchmark problems.