• 치과방사선
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• 제25권1호
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• pp.17-25
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• 1995

The purpose of this study was to obtain some informations for the radiographic differential diagnosis between odontogenic keratocyst and unicystic ameloblastoma in the mandible. The author compared and analysed the clinico-radiographic features of 48 cases of odontogenic keratocyst and 32 cases of unicystic ameloblastoma. The obtained results were as follows : 1. Odontogenic keratocyst and unicystic ameloblastoma occurred the most frequently in the 2nd and 3rd decades, and both lesions occurred with slight predilection in males. The most frequent lesional site was molar area in odontogenic keratocyst(50.0％) and mandibular angle and ramus area in unicystic amelobla-stoma(71.9％). 2. Cortical thinning and expansion were observed with similar occurrences in odontogenic keratocyst(77.l％) and in unicystic ameloblastoma(72.9％). 3. Typical undulating lesional border was observed more frequently in odontogenic keratocyst(79.2％) than in unicystic ameloblastoma(46.9％). 4. Well-defined lesional outline occurred more frequently in odontogenic keratocyst(97.9％) than in unicystic ameloblastoma(53.1％). 5. Root resorption of adjacent teeth occurred more frequently in unicystic ameloblastoma(65.2％) than in odontogenic keratocyst(18.8％) respectively, but loss of lamina dura was frequently observed in odontogenic keratocyst(79.2％). And tooth displacement occurred more frequently in odontogenic keratocyst(50.0％) than in unicystic ameloblastoma(17.4％). 6. Displacement of mandibular canal occurred more frequently in odontogenic keratocyst(75.0％) than in unicystic ameloblastoma(61.5％). 7. Inhomogeneous lesional radiolucency occurred more frequently in unicystic ameloblastoma(53.l％) than in odontogenic keratocyst(39.6％).

• 한국정보통신학회논문지
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• 제17권3호
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• pp.627-633
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• 2013

무선이동통신 시스템에서 두 수열의 상호상관 함숫값은 통화 품질과 사용자 수를 결정하는데 있어 큰 영향을 끼치고 있다. 본 논문에서는 주기 $2^n-1$인 m-수열에 새로운 데시메이션 $d=\frac{2^{m-st-1}}{2^s-1}(2^n+2^{st+s+1}-2^{m+st+1}-1)$를 적용하여 또 다른 m-수열을 생성하고 두 수열의 상호상관 함숫값과 그 값들의 발생횟수를 결정한다.

• 한국IT서비스학회지
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• 제11권sup호
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• pp.177-189
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• 2012

We developed the ocean disaster detection system(OD2S) which copes with the occurrences of ocean disasters (e. g. the red and green tide, the oil spill, the typhoon, and the sea ice) by converging and integrating the ocean color remote sensing using the satellite and the information technology exploiting the mass data processing and the pattern recognitions. This system which is based on the cosine similarity detects the ocean disasters in real time. The existing ocean color sensors which are operated in the polar orbit platforms cannot conduct the real time observation of ocean environments because they support the low temporal resolutions of one observation a day. However, geostationary ocean color imager(GOCI), the first geostationary ocean color sensor in the world, produces the ocean color images(e. g. the chlorophyll, the colored dissolved organic matter(CDOM), and the total suspended solid(TSS)), with high temporal resolutions of hourly intervals up to eight observations a day. The evaluation demonstrated that the OD2S can detect the excessive concentration of chlorophyll, CDOM, and TSS. Based on these results, it is expected that OD2S detects the ocean disasters in real time.

• 대기
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• 제18권4호
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• pp.249-266
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• 2008

The tendencies for teleconnection with a time lag and other characteristics of Korean summer droughts have been investigated and some clues to predict the drought occurrences several months before have been found. First, the May and June droughts in Korea are simultaneous with those over the northwestern part of Korea owing to the relation with the baroclinic wave. However, the July and August droughts occur over the mid-latitudes or southern part of Korea owing to the relation with the Changma front. Second, several months before the MJJA droughts in Korea, it is found that the effective drought index (EDI) over particular areas (hereafter, referred to as the omen areas) is large. Thailand, Carolina Island, Mongolia, and Central Bengal Bay were selected as the omen areas. Third, when the monthly minimum EDI (MME) of the omen area in winter is more than 0.7, it signifies that the precipitation is above normal, Korea has almost always experienced a summer drought. However, the droughts occurring with this type of relationship only represent half of the MJJA droughts in Korea. Fourth, the relationships between the Korean drought and the precipitation over omen areas in low latitudes are not valid over all the eight precipitation areas in Korea, but only over Areas I, II, and III, where heavy rains occur during spring and summer.

• The Korean Journal of Pain
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• 제28권3호
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• pp.193-197
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• 2015

Background: Herpes Zoster is a disease that occurs after the virus is reactivated due to infection of the varicella virus in childhood. Risk factors are advanced age, malignant neoplasm, organ transplantation, immunosuppressive agents taking are known. The purpose of this study was to investigate the relationship between the seasonal effect and other risk factors on the incidence of herpes zoster. Methods: The medical records of 1,105 patients admitted to the outpatient diagnosed with herpes zoster were retrospectively examined. The patients' sex, age, dermatome, onset, underlying disease, residential areas were collected. Results: The incidence of women outnumbered men and increased for those above the age of 50. The number of occurrences of herpes zoster patients was higher in the spring and summer than in winter. Unlike men, women had the most frequent outbreaks in March. The most common occurrence of dermatome is in the thoracic region. The number of occurrence was similar on the left as the right. Conclusions: In this study, herpes zoster occurs more often in women than in men and more frequently occurs in women in the spring and summer.

• 한국경영과학회지
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• 제23권3호
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• pp.135-151
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• 1998

The demand of large capacity in coming cellular systems makes inevitable the deployment of small cells, rendering more frequent handoff occurrences of calls than in the conventional system. The key issue is then how effectively to reduce the chance of unsuccessful handoffs, since the handoff failure is less desirable than that of a new call attempt. In this study, we consider the control policies which give priority to handoff calls by limiting channel assignment for the originating new calls, and allow queueing the new calls which are rejected at their first attempts. On this system. we propose the problem of finding an optimal call control strategy which optimizes the objective function value, while satisfying the requirements on the handoff/new call blocking probabilities and the new call delay. The objective function takes the most general form to include such well-known performance measures as the weighted average carried traffic and the handoff call blocking probability. The problem is formulated into two different linear programming (LP) models. One is based on the direct employment of steady state equations, and the other uses the theory of semi-Markov decision process. Two LP formulations are competitive each other, having its own strength in the numbers of variables and constraints. Extensive experiments are also conducted to show which call control strategy is optimal under various system environments having different objective functions and traffic patterns.

• 식물병연구
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• 제8권2호
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• Korean Journal of Acupuncture
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• 제33권1호
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• pp.18-32
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• 2016

Objectives : This study aims to analyze the co-occurrence of pathological symptoms and corresponding acupoints as documented by the comprehensive acupuncture and moxibustion records in the classical texts of Far East traditional medicine as an aid to a more efficient understanding of the tacit treatment principles of ancient physicians. Methods : The Classic of Nourishing Life with Acupuncture and Moxibustion(Zhenjiu Zisheng Jing; hereinafter ZZJ) was selected as the primary reference book for the analysis. The pathology-acupoint co-occurrence analysis was performed by applying 4 values of vector space measures(weighted Euclidean distance, Euclidean distance, $Cram\acute{e}r^{\prime}s$ V and Canberra distance), which measure the distance between the observed and expected co-occurrence counts, and 3 values of probabilistic measures(association strength, Fisher's exact test and Jaccard similarity), which measure the probability of observed co-occurrences. Results : The treatment records contained in ZZJ were preprocessed, which yielded 4162 pathology-acupoint sets. Co-occurrence was performed applying 7 different analysis variables, followed by a prediction simulation. The prediction simulation results revealed the Weighted Euclidean distance had the highest prediction rate with 24.32%, followed by Canberra distance(23.14%) and association strength(21.29%). Conclusions : The weighted Euclidean distance among the vector space measures and the association strength among the probabilistic measures were verified to be the most efficient analysis methods in analyzing the correlation between acupoints and pathologies found in the classical medical texts.

• Water Engineering Research
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• 제6권2호
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• pp.63-71
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• 2005

Nowadays Climate disasters are frequently happening due to occasional occurrences of EI Nino and La Nina events and among them, water shortage is one of the serious problems. To cope with this problem, climate model simulations can give very helpful information. To utilize the climate model for enhancing the water resources planning techniques, probabilistic measures of the effectiveness of global climate model (GCM) simulations of an indicator variable for discriminating high versus low regional observations of a target variable are proposed in this study. The objective of this study is to present the various analysis methods to find the suitable application methods of GCM information for Korean water resources planning. The basic formulation uses the significance probability of the Kolmogorov-Smirnov test for detecting differences between two variables. The various methods for adopting correct association, changing the window size, discrimination condition, and the use of temporally down scaled data were proposed to find out the suitable way for Korean water resources planning.

• 한국화재소방학회논문지
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• 제23권1호
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• pp.15-20
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• 2009

산불을 효율적으로 관리하기 위해서는 지역별 산불 행동 특성에 대한 이해가 요구된다. 본 논문에서는 전국 시 군 구 단위고 산불통계 자료를 이용하여 발생 및 확산 특성을 분석하였다. 이를 위해 1991년 부터 2007년까지 17년간 발생건수, 연소면적, 확산속도, 건당 면적 자료를 이용하여 산불 특성에 따라 군집을 분류하고 GIS를 이용하여 공간적 분포 특성을 분석하였다 분석결과, 산불의 공간적 특성 변이가 뚜렷하게 관찰되었고, 전국 시 군 구는 산불위험성에 따라 5개의 군집으로 분류할 수 있었다. 대도시와 인근 지역은 산불위험이 낮은 군집으로 분류되었으나, 강원도 영동지방 4개 시 군은 가장 위험한 군집으로 분류되었다. 그 뒤를 이어 남, 서해안에 인접한 시 군 구의 산불위험성이 높았다.