• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.369-370
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• 2008

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2000년도 추계총회 및 학술발표회
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• pp.7-7
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• 2000

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3257-3265
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• 2015

Background: Radiotherapy is an important treatment of choice for breast cancer patients after breast-conserving surgery, and we compare the feasibility of using dual arc volumetric modulated arc therapy (VMAT2), single arc volumetric modulated arc therapy (VMAT1) and Multi-beam Intensity Modulated Radiotherapy (M-IMRT) on patients after breast-conserving surgery. Materials and Methods: Thirty patients with breast cancer (half right-sided and half left-sided) treated by conservative lumpectomy and requiring whole breast radiotherapy with tumor bed boost were planned with three different radiotherapy techniques: 1) VMAT1; 2) VMAT2; 3) M-IMRT. The distributions for the planning target volume (PTV) and organs at risk (OARs) were compared. Dosimetries for all the techniques were compared. Results: All three techniques satisfied the dose constraint well. VMAT2 showed no obvious difference in the homogeneity index (HI) and conformity index (CI) of the PTV with respect to M-IMRT and VMAT1. VMAT2 clearly improved the treatment efficiency and can also decrease the mean dose and V5Gy of the contralateral lung. The mean dose and maximum dose of the spinal cord and contralateral breast were lower for VMAT2 than the other two techniques. The very low dose distribution (V1Gy) of the contralateral breast also showed great reduction in VMAT2 compared with the other two techniques. For the ipsilateral lung of right-sided breast cancer, the mean dose was decreased significantly in VMAT2 compared with VMAT1 and M-IMRT. The V20Gy and V30Gy of the ipsilateral lung of the left-sided breast cancer for VMAT2 showed obvious reduction compared with the other two techniques. The heart statistics of VMAT2 also decreased considerably compared to VMAT1 and M-IMRT. Conclusions: Compared to the other two techniques, the dual arc volumetric modulated arc therapy technique reduced radiation dose exposure to the organs at risk and maintained a reasonable target dose distribution.

• 한국환경과학회지
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• 제26권3호
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• pp.311-324
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• 2017

To certificate change in the geochemical characteristics of surface sediments in the main stream of the Nakdong River, surface sediments from 12 sampling sites during the first and second half year (total 24 sampling sites) were collected and analyzed for grain size, ignition loss, total organic carbon and heavy metal content. Surface sediments mainly composed of sand (coarse and medium sand) and fining changed from the first half to the second half of the year. Ignition loss, total organic carbon and heavy metals content increased in the second half of the year. Some heavy metals (Zn, Ni and Cu) were found to be at the lowest effect levels according to Ontario sediment quality guidelines. Additionally, most heavy metals were found to be at the non polluted level and level I according to USEPA sediment quality standards and National Institute of Environmental Research sediment pollution evaluation standard, respectively. The enrichment factor (< 1) and index of geoaccmulation (< 0) were non polluted in the study area. The correlation analysis results showed that ignition loss, total organic carbon and heavy metal content were highly correlated with grain size. Regarding changes in geochemical characteristics of surface sediments in the study area, grain size fine and organic matter and heavy metal content increased in the second half year. Nonetheless these results indicated pollution levels that did not adversely affect the benthos.

• 한국의류학회지
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• 제36권1호
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• pp.27-35
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• 2012

This study locates typical Korean fashion images in domestic and foreign fashion journals to advance Korea's international image in contemporary global fashion markets. The investigation of the frequency of articles and their types (so as to inquire into interest in Korean fashion in the global fashion markets) showed that for the appearance frequency of domestic articles studied, a good number of articles were published in the first half of 2008 and in 2009. In the case of foreign articles, the number of them increased from the second half of 2008 and the majority of articles were shown in the first half of 2010. Second, the investigation of the appearance features by article type studied in order to understand how Korean fashion played a role in the world's markets. The majority of articles were related to fashion brands that entered Chinese market in fashion brand articles in the case of domestic articles; however, many foreign articles introduced designers that participated in global fashion collections in Paris and New York. Third, as a result of analyzing typical key words by article type in order to find key words which could enhance Korea's fashion national image representing, we could confirm that 'Korean designers' can be a typical key words to represent Korean fashion. The key word most exposed in both domestic and foreign articles was 'designer Lie Sang Bong' and only his articles contained the content about influential Korean design materials.

• 한국자기학회지
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• 제18권6호
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• pp.201-205
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• 2008

호이슬러 구조의 대표적 반쪽금속인, $Co_2MnSi$에서 에너지 간격이 생기는 원인을 실제적인 전자구조 계산을 통해 검토하기 위해 호이슬러 구조에서 부분을 이루는 zinc-blende 구조의 CoMn과 하프 호이슬러 구조를 가진 CoMnSi, 그리고 가상적인 화합물인 $Co_2Mn$의 전자구조를 제일원리 방법을 통해 계산하였다. 각 화합물에서 계산된 상태밀도를 이용하여 띠 혼성이나 에너지 간격 등을 고찰한 결과 $Co_2MnSi$에서 에너지 간격이 생기는 원인이 Galanakis 등이 설명한 방식이 그대로 적용되지 않았으며, Si 원자의 역할 또한 중요함을 알게 되었다. 각 화합물에서 얻은 다수스핀과 소수스핀 전자수를 통해 이들 화합물의 자성도 고찰하였다.

• 농약과학회지
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• 제18권2호
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• pp.61-68
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• 2014

사과 중 살응애제 etoxazole 및 flufenoxuron의 출하 전 잔류허용기준(PHRL)을 설정하기 위해 각 농약의 생물학적 반감기와 감소상수가 산출되었다. 안전사용기준의 희석배수에 따라 조제된 각 농약을 사과에 대하여 각각 1회 및 3회 살포한 후 사과 중 일자별 잔류량을 조사하였으며, 잔류시험 결과들은 first order kinetics의 지수감소식에 대입되었다. 시험기간 중 두 농약의 잔류량은 모두 잔류허용기준(MRL) 미만으로 나타났으며, 사과 중 생물학적 반감기를 조사한 결과 etoxazole의 경우 1회 처리구에서 8.8일, 3회 처리구에서 21.7일로 나타났다. 반면에 flufenoxuron은 1회 처리구에서 21.7일, 3회 처리구에서 23.1일로 나타나 etoxazole 보다 반감기가 더 길었다. 사과 중 각 농약의 감소상수는 etoxazole은 0.0788, flufenoxuron은 0.0319이었으며, 산출된 감소상수들을 대입하여 PHRL을 계산하였다. 그 결과, 안전사용기준을 준수한 농약살포 시 출하 일주일 전 농약의 잔류량이 etoxazole은 0.87 mg/kg, flufenoxuron은 0.88 mg/kg 이하이면 출하 시 잔류량이 MRL 이하일 것으로 예측되었다.

• Acta Via Serica
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• 제3권2호
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• pp.23-48
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• 2018

The Silk Road usually implies a network of trade and communications that stretched from east to west and connected China and the countries of the Far East via Central Asia and the Middle East to the eastern Mediterranean, or through the northern coast of the Caspian Sea and the Volga basin to the Black Sea coast. However, at certain historical stages, a network of maritime and overland routes stretching from north to south, commonly called the Volga-Caspian trade route, also played a significant role in international trade and cultural contacts. The geopolitical realities of the early Middle Ages relating to the relationship of Byzantium, the Sassanid Empire, and the West Turkic Khaganate, the advance of the Arab Caliphate to the north, the spread of Islam in the Volga region, the glories and fall of the Khazar State, and the Scandinavian campaigns in the Caucasus, closely intertwined with the history of transport and communications connecting the north and south through the Volga-Caspian route. In a later era, the interests of the Mongolian Uluses, and then the political and economic aspirations of the Ottoman Empire, the Safavid State, and Russia, collided or combined on these routes. The article discusses trade contacts existing between the north and the south in the 15th and first half of the 17th century along the routes on the western coast of the Caspian Sea.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.212-217
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• 1993

In this paper, characteristics of the motions of a human arm are investigated experimentally. When the conditions of the target point are restricted, human adjusts its trajectory and velocity pattern of the arm to fit the conditions skillfully. The purpose of this work is to examine the characteristics of the trajectory, velocity pattern, and the size of the duration in the following cases. First, we examine the case of point-to-point motion. The results are consistent with the minimum jerk theory. However, individual differences in the length of the duration can be observed in the experiment. Second, we examine the case which requires accuracy of positioning at the target point. It is found that the velocity pattern differs from the bell shaped pattern explained by the minimum jerk theory, and has its peak in the first half of the duration. When higher accuracy of the positioning is required, learning effects can be observed. Finally, to examine the case which requires constraint of the arm posture at the target point, we conduct experiments of a human trying to grasp a cup. It is considered that this motion consists of two steps : one is the positioning motion of the person in order to start the grasping motion, the other is the grasping motion of the human's hand approaching toward the cup and grasping it. In addition, two representative velocity patterns are observed : one is the similar velocity pattern explained in the above experiment, the other is the velocity pattern which has its relative maximum in the latter half of the duration.

• 천문학회보
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• 제41권2호
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• pp.68.1-68.1
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• 2016

The solar eclipse affects terrestrial environments in various aspects. For instance, it is well known that the electron concentration and current density decrease in the ionosphere due to the reduction of solar irradiation during solar eclipse. In this study, we carry out the statistical analysis of x, y, z, H-components, and the intensity of the geomagnetic field using the ground based geomagnetic data observed during the solar eclipses from 1991 to 2016. First, we confirm that characteristic decreases in the x and H-components can be seen in the vicinity of the maximum eclipse time at the observing site. Second, we find that the decrease in x and H-components is more conspicuous during the total solar eclipse rather than the partial or annular eclipses. We also find that such a dip is likely to be noticed when the observing site locates in the second half compared to the first half of the eclipse path, as well as when the eclipse occurs in dusk side than in dawn side. Third, we find that reductions in the ground geomagnetic field by the solar eclipse are more evident in the ascending phase of the solar cycle than in the descending phase. Finally, we briefly discuss implications of our findings.