• Nuclear Engineering and Technology
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• 제25권3호
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• pp.361-370
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• 1993

국내 가압 경수로는 핵연료 재장전후 해당 주기 노심핵설계의 타당성 및 안선 제한치의 만족 여부를 확인하기 위하여 저출력에서 노물리 시험을 수행한다. 그러나 고리 3호기 7주기를 포함한 일부 저출력 노물리 시험 중 step 반응도를 삽입한 후에도 반응도가 서서히 증가하는 기이한 현상이 나타났다. 이러한 현상은 시험시 중성자속 준위가 낮고 노외 핵계측기로 비보상형 전리함을 사용하기 때문에 감마 background가 존재하여 생기는 것이다. 이로 인해 노물리 시험 결과는 많은 오차를 포함할 수도 있는 것이다. 본 연구에서는 반응도가 증가하는 현상을 정량적으로 분석하고 기준 제어봉 제어능 측정 시험을 모사함으로써 노물리 시험 결과의 오차를 줄일 수 있는 방법을 제시하고 이후의 노물리 시험에 적용하여 확인하였다. 또한 감마 background 준위를 산정한 후 중성자속 준위를 조정하여 기준 제어봉 제어능 측정 시험을 통해 감마 background의 영향을 받지 않는 중성자속 준위를 결정하였다. 결정된 중성자속 준위는 핵가열이 발생하는 중성자속의 3/10이다. 이것은 기존의 상한치보다 3배 증가된 것이다. 이 결과는 고리 4호기 7주기 및 영광 1호기 7주기 노물리 시험에 성공적으로 적용되었다.

• 상하수도학회지
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• 제28권3호
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• pp.345-358
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• 2014

For introducing the groundwater quality assessment using background concentration of groundwater, several methods had been studied to estimate the background concentration of groundwater and to suggest the background concentration of study area. Some methods such as Box whisker plot, Percentile and Cumulative probability distribution had been adopted to estimate background concentration, and it was evaluated that the Cumulative probability distribution method presents more reasonable background concentration because it can consider the data distribution. So we estimated the background concentration of study area using cumulative probability distribution method. We suggested the background concentration for each hydrogeology respectively in case hydrogeological water quality similarity is very low.

• 한국게임학회 논문지
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• 제2권1호
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• pp.49-54
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• 2002

In this paper we propose the methodology for 3D background image construction in computer games. This methodology was developed based on TIP (Tour Into the Picture) using a vanishing line Proposed by Kang et at. The methodology Proposed in this study can simply implement a 3D background for a computer game with a background model which is very complex or based on a real picture. Compared to the graphics technologies generally used, the proposed methodology does not need the process of modeling elaborate 3D information of a background, and hence can display the background even on a low grade personal computer using a small reference image. TIP technology was successfully applied to the implementation of a background model for a computer game and was found to be appropriate especially for real time games.

• Nuclear Engineering and Technology
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• 제34권6호
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• pp.545-552
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• 2002

We developed an ultra low background gamma ray spectrometer particularly suitable for experiment which require lower detection limit. The background of a germanium spectrometer is suppressed by applying active and passive shielding technique at the same time. The active shielding devices consist of plastic scintillating plates of 50 mm thick and anti-coincidence electronic system. The shielding is made of 150 mm thick walls of very low activity lead,20 mm with activity of <10 Bq/kg and 130 mm with activity of <50 Bq/kg. The observed background count rates are 1.2 $s^{-1}$ and 0.36 $s^{-1}$ without and with the active shielding, respectively, overall the energy regions from 30 keV to 3 MeV The cosmic ray induced background is suppressed by a rate of 0.8 $s^{-1}$ at the present work. The detection efficiency curve necessary to obtain the radioactivity of environmental samples has been precisely determined on the energy regions from 80 to 2000 keV with a 10$^3$ ml marinelli beaker sample, consisting of the calibrated radionuclides $^{109}$ Cd, $^{57}$ CO, $^{139}$ Ce, $^{203}$ Hg, $^{113}$ Sn, $^{85}$Sr, $^{137}$ Cs, $^{60}$ Co and $^{88}$ Y. Virtues Of the method are demonstrated by measuring the activity of $^{137}$ Cs contained in the powdered milk.

• 대한세포병리학회지
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• 제8권2호
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• pp.135-142
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• 1997

Mucoepidermoid carcinoma is the most common malignant neoplasm of the salivary gland, compring between 30 and 40%. Fine needle apsiration cytology was performed in five patients with mucoepidermoid carcinoma. The patients consisted of three males aged of 42, 48, and 60 years, and two females aged 36, and 56 years. The primary tumor sites were the parotid gland in four patients and the submandibular gland in the rest one. The histologic grades were low in one patient, intermediate in two patients and high in other two. In our experience, the common cytologic findings of low grade subtype were predominent mucous cells with some intermediate cells in an abundant mucinous background. The cytologic findings of intermediate grade subtype were predominant clusters of intermediate cells with or without mucous cells in an abundant mucinous background. And the cytologic findings of high grade subtype were predominant clusters of epidermoid cells with intermediate cells in a bloody background. Cytologic pleomorphism and atypia were more severe in high grade than low and intermediate grade, and nucleoli were more frequently noted in epidermoid cells. In low grade, it is very difficult to decide the benignancy or malignancy of the tumor. In fact, the presence of mucous cells in a mucinous background should rule out any other type of well differentiated carcinoma.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.631-636
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• 2009

컴퓨터 비전 분야에서 전경을 추출하기 위한 영역 분할(segmentation) 방법에 대한 연구가 활발히 진행되어 왔다. 특히, 전경이 배제된 배경 영상과 현재 프레임의 차이를 이용하여 전경을 추출하는 배경 차분(background subtraction) 방법은 요구하는 계산량에 비해 우수한 품질의 전경 추출이 가능하므로 실시간 처리가 필요한 비전 시스템에 다양하게 응용되고 있다. 그러나 배경 차분 방법만을 이용하여서는 배경이 동적으로 변하는 환경에서 정확한 전경을 추출해 내지 못하는 단점이 있다. 본 논문에서는 정적인 배경과 동적인 배경이 공존하는 환경에서 영역 분할을 효과적으로 수행하는 방법을 제안한다. 제안된 방법은 정적인 배경 영역에 대해서는 기존의 배경 차분 방법을 이용하여 전경을 추출하고, 동적인 배경 영역에 대해서는 깊이 정보를 이용하여 전경을 추출하는 하이브리드 방식을 사용한다. 정적인 배경에 동적인 영상을 프로젝터로 투영하는 환경에서 제안된 방법의 효율성을 검증하였다.

• 대한인간공학회지
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• 제27권3호
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• pp.15-22
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• 2008

The purpose of this study was to define the effects of noise and background music on the trunk muscle fatigue during dynamic lifting and lowering tasks. Six healthy male subjects with no prior history of low back disorders participated in this study. The participants were exposed to two levels of background noise such as 40dB noise and 90dB noise and three levels of background music such as no music, slow music, and fast music. Six different combinations of background noise and background music were played while the participants were performing the lifting task at 15% level of Maximum Voluntary Contraction. Electromyography signals from six muscles were collected and fatigue levels were analyzed quantitatively. In results, the 90dB noise increased trunk muscle fatigue and slowed down the recovery. The trunk muscle fatigue was the lowest when the fast music was played for as background. After recovery, the 90dB noise increased trunk muscle fatigue. The trunk muscle fatigue was the lowest when the slow music was played for as background. The results can be useful to manage the cumulative fatigue of trunk muscles due to background noise and music during repetitive lifting and lowering tasks in industry.

• 한국통신학회논문지
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• 제22권4호
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• pp.771-781
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• 1997

In order to solve the problem of uncovered background region due to the region-due to the region-based motion estimation, this paper presents a new method which generates the uncovered region memory using motion estimation and shows the application of the algorithm for very low bit rate video coding. The proposed algorithm can be briefly described as follows it detects the changed region by using the information of FD(frame difference) and segmentation, and then as for only that region the backward motion estimation without transmission of shape information is done. Therefore, from only motion information the uncovered background region memory is generated and updated. The contents stored in the uncovered background region memory are referred whenever the uncovered region comes into existence. The regions with large prediction error are transformed and coded by using DCT. As results of simulation, the proposed algorithm shows the superior improvement in the subjective and objective image quality due to the remarkable reduction of transmission bits for prediction error.

• 반도체디스플레이기술학회지
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• 제19권2호
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• pp.31-36
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• 2020

Most of the background subtraction algorithms show good performance in static scenes. In the case of dynamic scenes, they frequently cause false alarm to "temporal clutter", a repetitive motion within a certain area. In this paper, we propose a robust technique for the multiple interval pixel sampling (MIS) algorithm to handle highly dynamic scenes. An adaptive threshold scheme is used to suppress false alarms in low-confidence regions. We also utilize multiple background models in the foreground segmentation process to handle repetitive background movements. Experimental results revealed that our approach works well in handling various temporal clutters.

• 한국인공지능학회지
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• 제8권2호
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• pp.17-22
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• 2020

Purpose: After entering the 21st century, a new industrial revolution, i.e. industrial revolution 4.0, which is characterized by intelligence, automation and networking, has opened the curtain of the "industry 4.0" era. In recent years, "low-carbon economy" has been a development goal that has been paid close attention to and adhered to at home and abroad. As a major economic province, Shandong Province has not only brought about rapid economic growth, but also caused rapid environmental deterioration due to its high energy consumption, high dependence and high environmental pollution. In this environment, low-carbon economy has become an inevitable trend in the development of foreign trade in Shandong Province. Based on the current situation of foreign trade in Shandong Province and various existing problems, this paper explores the relationship between low-carbon economy and foreign trade in Shandong Province under this strategic background. Research design, data and methodology: By selecting the data from 2008 to 2017, using the carbon emission coefficient method to measure the CO2 emissions in the past decade, analyzing the impact of ecological factors on trade, selecting the most representative GDP and total imports for regression analysis, it is proved that they have a real impact on CO2 emissions. The total GDP is positively correlated with carbon emissions, while the total import is negatively correlated with carbon emissions. Results:This paper discusses the impact of low-carbon economy on foreign trade of Shandong Province from the perspective of foreign trade. Especially in today's "low-carbon economy" background. Conclusions:it is helpful for relevant departments to formulate relevant policies and promote the sustainable development of foreign trade in Shandong Province.