• 한국정밀공학회지
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• 제20권3호
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• pp.42-49
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• 2003

In this paper, we provide the results of polishing temperature distribution by way of infrared ray measurement system as well as polishing resistance, which can be interpreted as tribological aspects of CMP, using force measurement system. The results include the trend of polishing temperature, its distribution profile and temperature change during polishing. The results indicate that temperature affects greatly to the removal rate. Polishing temperature increases gradually and reaches steady state temperature and the period of temperature change occurs first tens of seconds. Furthermore, the friction force also varies as the same pattern with polishing temperature from high friction to low. These results suggest that the first period of the whole polishing time greatly affects the nonuniformity of removal rate.

• Journal of Welding and Joining
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• 제30권6호
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• pp.21-26
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• 2012

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.26-26
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• 2006

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.38-41
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• 2005

The observation data from MTP-5HE ofEPA are used to study the temperature inversion phenomenon in the lower boundary layer in Taipei, Taichung and Kaohsiung of Taiwan. Characteristics of temperature inversion at three cities are extracted using different classification methods. The characteristics of temperature inversion in Taichung and Kaohsiung show a similar trend but are different from that in Taipei. The numbers of the occurrence of temperature inversion in Taichung and Kaohsiung were much larger than that in Taipei. The main types of temperature inversion in Taiwan are radiation inversion and frontal inversion. Compared to frontal inversion, radiation inversion on average occurs at a lower altitude, lasts a longer period, has a deeper thickness, and reaches a higher temperature difference of inversion. Frontal inversion plays a significant role for the inversion event lasting over 12 hours.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권2호
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• pp.55-61
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• 2002

In this paper, 'lifetime-temperature rise model' based on the 'lifetime-resistance model' is theoretically Proposed, in order to find out the evaluation method of degradation and the residual lifetime by use of infrared image camera for electric connections/contacts. Two assumptions have been builded up for the 'lifetime-temperature rise model': one is associated with the linear relationship between the temperature ism ΔK and contact resistance, and the other the functional relationship between the temperature of electric connections/contacts and the operating time presenting in the 'lifetime-resistance model'. To prove the proposed model, experiments have been performed for various electric connections/contacts. From the experimental results, measured values were quite similar to the calculated values, which proved the above-mentioned two assumptions. Therefore, by use of 'lifetime-temperature rise model', it is possible to estimate the trend of degradation and the residual lifetime for electric connections/contacts through the temperature measurements .

• Spatial Information Research
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• 제15권3호
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• pp.267-278
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• 2007

국제사회는 기후변화에 따른 이상 현상의 징후가 발생함에 따라 이의 영향 예측을 위해 많은 모델들을 개발 및 적용하고 있다. 현재 우리나라에서도 여러 분야의 기후 영향모델 활용이 증가하면서 모델의 입력자료 중 특히 기후자료의 구축 방법 및 한반도 기후의 특성 파악에 대한 연구가 절실히 요구되고 있다. 본 연구에서는 보간을 위하여 공간통계학방법 중 IDSW(Inverse Distance Squared Weighting:거리자승역산가중)를 적용하였다. 이 방법은 미관측지점의 값을 추정하기 위하여 주변 관측지점들을 고려하며, 그 영향은 거리에 반비례함을 반영한다. 여기서 주변 관측지점 선정시 반경 100km내의 가장 인접한 순으로 최대 3개의 관측지점을 선택하게 제약을 두었다. 그 결과 한국의 기온과 강수량 모두 과거 30년 동안에 연평균 약 $0.4^{\circ}C$, 412mm 증가하는 것으로 나타났다. 또한 미래에도 2007년에 비해 2100년의 기온이 $3.96^{\circ}C$, 강수량이 319mm 증가하는 것으로 나타났다. 기후변이성의 특성은 과거 30년 동안 기온의 경우 강원도 일부지역이 높게 나타났으며 강수량의 경우 남부지역이 높게 나타났다. 변화 경향은 기온의 경우 강원도 지역이 변이성이 증가하는 경향을 보였으며, 강수량의 경우 남동부부지역이 변이성이 증가하는 경향을 보였다. 미래 30년간의 변이성 분석결과 기온은 중서부 지역에서, 강수량은 동부지역에서 높은 것으로 나타났고, 변화경향은 기온의 경우 남서부로 갈수록 변이의 정도가 증가되는 경향을 보였으며, 강수량의 경우 중서부와 남부 일부가 변이가 증가되는 경향을 보였다.

• Journal of Ecology and Environment
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• 제44권4호
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• pp.264-274
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• 2020

Background: Climate change has altered the various ecosystem processes including forest ecosystem in Himalayan region. Although the high mountain natural forests including treelines in the Himalayan region are mainly reported to be temperature sensitive, the temperature-related water stress in an important growth-limiting factor for middle elevation mountains. And there are very few evidences on growth performance of planted forest in changing climate in the Himalayan region. A dendrochronological study was carried out to verify and record the impact of warming temperature tree growth by using the tree cores of Pinus roxburghii from Batase village of Dhulikhel in Central Nepal with sub-tropical climatic zone. For this total, 29 tree cores from 25 trees of P. roxburghii were measured and analyzed. Result: A 44-year long tree ring width chronology was constructed from the cores. The result showed that the radial growth of P. roxburghii was positively correlated with pre-monsoon (April) rainfall, although the correlation was not significant and negatively correlated with summer rainfall. The strongest negative correlation was found between radial growth and rainfall of June followed by the rainfall of January. Also, the radial growth showed significant positive correlation with that previous year August mean temperature and maximum temperature, and significant negative correlation between radial growth and maximum temperature (Tmax) of May and of spring season (March-May), indicating moisture as the key factor for radial growth. Despite the overall positive trend in the basal area increment (BAI), we have found the abrupt decline between 1995 and 2005 AD. Conclusion: The results indicated that chir pine planted population was moisture sensitive, and the negative impact of higher temperature during early growth season (March-May) was clearly seen on the radial growth. We emphasize that the forest would experience further moisture stress if the trend of warming temperatures continues. The unusual decreasing BAI trend might be associated with forest management processes including resin collection and other disturbances. Our results showed that the planted pine forest stand is sub-healthy due to major human intervention at times. Further exploration of growth climate response from different climatic zones and management regimes is important to improve our understanding on the growth performance of mid-hill pine forests in Nepal.

• 한국수자원학회논문집
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• 제44권8호
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• pp.683-694
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• 2011

기후변화에 따른 지역적 영향인 기온 상승과 강수량 변화로 인한 수자원 변화 특성을 파악하기 위하여 기상청(KMA)으로부터 전국 59개 관측지점에 대해서 1973년부터 2009년까지 강수량 및 기온자료를 이용하여 산정한 강수효율자료와 국가수자원관리종합시스템(WAMIS)으로부터 1966년부터 2007년까지 PRMS 모의 유출량 자료를 수집, 분석하였다. 분석결과, 전반적으로 강수효율의 거동은 강수량의 변화 특성을 따르나 지역적으로 강수량이 증가함에도 불구하고 기온 상승에 따라 강수효율이 감소하는 거동을 보였으며, 이는 유출량의 변화 특성과 유사하였다. 또한 유출량의 평균대비 변화율은 강수량 변화보다 상당히 크게 나타나, 기후변화의 영향에 민감한 것으로 나타났다. 강수량이 증가하는 5월~9월을 제외한 전체 기간에 대하여 강수효율은 강수량보다 더 유의한 감소 경향을 나타내고 있어 해당기간의 가용 수자원량이 줄어들 것으로 판단되며, 이러한 특성은 봄, 가을 및 겨울철 수자원 관리에 반영되어야 할 것이다.

• Advances in environmental research
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• 제9권1호
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• pp.55-64
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• 2020

The problems with unsorted municipal waste are always associated with disposal issues as it requires a large area for landfilling or high energy used for incineration. In recent years, an autoclaving technique has been considered a promising approach which could minimize the volume of organic waste from being directly disposed or incinerated. In this work, an attempt was done to study the saccharification potential of organic residues under elevated temperature Thermal treatment involving hot water bath was applied to treat the organic residue ranging from 60℃ to 100℃ for 30 and 60 minutes. The result obtained showed an increasing trend for the concentration of glucose and carbohydrate. However, the result for lignocellulose content which contains various component includes extractive, holocellulose, hemicellulose, cellulose and lignin show variation. Based on the thermal treatment carried out, the result indicated that the trend of glucose and carbohydrate content. The highest percentage of glucose that can be obtained 978.602 ㎍/ml which could be obtained at 90℃ at 60 minutes. The carbohydrate also shows an increasing trend with 0.234 mg/ml as the highest peak achieved at 80℃ for 30 minutes treatment. However, it was found that the lignocellulose content varies with temperature and time. The statistical analysis was carried out using two-ways ANOVA shows an interaction effect between the independent variables (temperature and contact time) and the saccharification effects on the food wastes. The result shows a variation in the significant effect of independent variables on the changes in the composition of food waste.

• 환경영향평가
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• 제15권3호
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• pp.207-215
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• 2006

The purpose of this paper is to analyze the spatial distribution and change of the frequency of Yellow Sand days and to examine their relationship with atmospheric circular characteristics at the surroundings of the Korean peninsula. Yellow Sand days data are used by intensity, Siberian High Index and monthly mean temperature of the Northern Hemisphere. In the Middle-western region, the occurrence frequency of Yellow Sand days was higher during the study period (1973-2004). Also, the occurrence frequency of Yellow Sand days increased to latter half 16 years compared with the first half 16 years, and be clearer in Middlewest regions. Yellow Sand days frequency increased, and the trend was distinct in the Jungbu region during the study period. Increasing trend of Yellow Sand days frequency was significant for the recent 22 years. Yellow Sand days had a negative relationship with Siberian High Index in February and March. Therefore, Siberian High Index became weaker in the spring, and possibility for the occurrence of Yellow Sand days was generating larger. Yellow Sand days had a positive relationship in monthly mean temperature of the Northern Hemisphere. Especially, the case of the strong Yellow Sand days is significant. Recently, global warming might be affecting the occurrence of strong Yellow Sand days.