• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2003년도 추계학술발표논문집 (중)
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• pp.883-886
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• 2003

호스트의 위치를 동적으로 관리해야 하는 이동 통신망 환경에서 멀티캐스트 서비스 지원을 위하여 기존 고정 통신망 환경에서 사용되는 멀티캐스트 프로토콜의 사용은 부적합하다. 이동 호스트의 이동성을 보장하기 위하여 IETF에서는 원격 가입(remote subscription)과 양방향 터널링(bidirectional tunneling)을 제안하였다. 하지만, 이 방법들 또한 경로 비최적화 문제, 멀티캐스트 트리의 빈번한 재구성 등의 문제점을 가지고 있다. 본 논문에서는 Mobile IPv4 지역 등록 기법을 이용함으로써 이동 호스트의 이동 후 등록 절차에서 나타나는 지연을 줄였다. 그리고, 멀티캐스트 트리의 빈번한 재구성을 줄이기 위해서 로컬 네트워크의 GFA(gateway foreign agent)가 실제 트리에 가입한다. 그러므로 로컬 네트워크 내의 움직임은 트리 재구성에 영향을 미치지 않도록 하였다. 또한 이동 호스트는 이전 DFA에게 멀티캐스트 데이터를 포워딩 받을 수도 있고, 현재의 GFA가 직접 멀티캐스트 트리에 가입하여 데이터를 받을 수 있다. 이러한 기법들을 사용하여 경로 비최적화 문제를 해결하고, 트리 재구성 빈도를 줄일 수 있는 방안을 제시하였다.

• 대한치과기공학회지
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• 제26권1호
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• pp.9-34
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• 2004

The present study reviews the license registration status of dental technicians and dentists from 1970 to 2002, the number of technician members of The Korea Dental Technician Association from 1990 to 2003, and the number of dentist members in 2003. It also considers the yearly membership fluctuations, its growth rates, yearly increase/decrease, the rate of dentist to dental technician, regional distribution of association members, regional yearly increase/decrease of the members, and the regional distribution of dentists and dental technicians. The purpose is to identify and predict the problems in the demand/supply of dental technicians and the regional imbalance of manpower distribution. By doing so, this study attempts to propose the appropriate standard for the supply of dental technicians and point out the necessity of making mid- or long-term plans for ensuring the efficiency of manpower supply and balanced regional distribution. The result is as follows: 1. The number of dental technicians and dentists in 2002 has grown 36.79 and 9.27 times from 1970, and 2.20 and 2.05 times from 1990, respectively. It tool 11 years for the twofold increase of dental technicians from 1990, one year faster than the same increase of dentists. The number of dental technicians per a dentist was the lowest in 1972 (0.21 person), and the highest in 2002 (0.86 person). Specifically, the fastest growth was observed for a year from 1983 (0.47 technician per a dentist) to 1984 (0.6). From 1984 to 1986, the ratio grew by 0.1 every year. Summing up the numbers of dentists and dental technicians who passed the national certification examination, this study predicted the number of dental technicians per a dentist to be 0.88 in 2003, and 0.90 in 2004. 2. From 1990 to 2003, the average distribution of dental technician was 71.76% in the metropolitan areas and 28.24% in other smaller regions. The proportion of dental technicians working in the three major cities (Seoul, Busan, and Daegu) was the lowest in 2001 (52.39%) and the highest in 1996 (62.66%). The majority number of dental technicians who practiced in the metropolitan areas (about 70% of the entire population) were in service in the three major cities. 3. Compared with 1990, the number of dental technicians in 2003 grew 2.28 times in the large cities, and 2.05 times in other smaller regions. The yearly growth rate was the highest in 1994 over the previous year: 26.06% in large cities and 17.86% in the other regions. In the large metropolitan cities, the growth rate was the highest in Incheon (5.8 times for 5 years from 1998 to 2003), In the rest of the regions, the increase of dental technicians was the highest in Gyeonggi (6.5 times from 1990 to 2003). 4. In 2003, as much as 73.40% of all the members of the Korea Dental Technician Association were distributed in the large metropolitan cities, and the rest 26.60% were in other smaller regions. Meanwhile, 54.35% of the dentists practiced in the metropolitan cities, and the rest 45.65% were in service at other regions. This result indicates that more dental technicians than dentists are concentrated in large cities. More than half of all the technician members of the Association are distributed in the three major cities (i.e. Seoul, Busan, Daegu). On the other hand, 42.03% of dentist members are in these three cities and 53.97% of them practice in Seoul, Gyeonggi, and Busan. In 2003, the ratio of dentist to dental technician is 1:0.43 in general, while the ratio is 1:0.58 in the metropolitan cities, and 1:0.43 in other regions. In 2003, 33.30% of all the certified dental technicians are the member of the Korea Dental Technician Association, while 66.82% of all the licensed dentists are its members.

• 대한원격탐사학회지
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• 제40권4호
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• pp.387-396
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• 2024

대부분의 고해상도 위성영상은 rational polynomial coefficients (RPC) 정보를 제공하여 지상좌표와 영상좌표 간 변환을 수행한다. 그러나 초기 RPC에는 기하학적 오차가 존재하여 ground control points (GCPs)와의 정합을 통해 보정을 수행하여야 한다. GCP chip은 항공정사영상에서 추출한 높이 정보가 포함된 작은 영상 패치(patch)이다. 많은 선행연구에서는 영역 기반 정합 기법을 사용하여 고해상도 위성영상과 GCP chip 간 정합을 수행하였다. 계절적 차이나 변화된 지역이 존재하는 영상에서는 화소값에 의존하는 정합이 어렵기 때문에 윤곽 정보를 추출하여 정합을 수행하기도 한다. 그러나 일반적으로 사용하는 canny 기법으로 정합에 용이한 윤곽을 추출하기 위해서는 위성영상의 분광 특성에 적절한 임계치를 설정해주어야 하는 문제가 존재한다. 따라서 본 연구에서는 위성영상의 지역별 특성에 둔감한 윤곽 정보를 활용하여 RPC 보정을 위한 정합을 수행하고자 한다. 이를 위해 딥러닝 기반 윤곽 정보 추출 네트워크인 pixel difference network (PiDiNet)를 활용하여 위성영상과 GCP chip의 윤곽맵(edge map)을 각각 생성하였다. 그 후 생성된 윤곽맵을 normalized cross-correlation과 relative edge cross-correlation의 입력데이터로 대체하여 영역 기반의 정합을 수행하였다. 마지막으로 RPC 보정에 필요한 변환모델 계수를 도출하기 위하여 data snooping 기법을 반복적으로 적용하여 참정합쌍을 추출하였다. 오정합쌍을 제거한 참정합쌍에 대해 root mean square error (RMSE)를 도출하고 기존에 사용하던 상관관계 기법과 결과를 정성적으로 비교하였다. 실험 결과, PiDiNet은 약 0.3~0.9 화소의 RMSE 값 분포를 보였으나 canny 기법에 비해 두꺼운 윤곽을 나타내어 일부 영상에서 미세하게 정확도가 저하되는 것을 확인하였다. 그러나 위성영상 내 특징적인 윤곽을 일관적으로 나타냄으로써 정합이 어려운 지역에서도 정합이 잘 수행되는 것을 확인하였다. 본 연구를 통해 윤곽 기반 정합 기법의 강인성을 개선하여 다양한 지역에서의 정합을 수행할 수 있을 것으로 예상된다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권sup3호
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• pp.191-195
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• 2016

Breast cancer is the most frequent cancer in females. Its incidence is higher in developed countries than in developing ones partly due to variation in risk exposure and partly due to better detection methods. Scattered evidence in Basrah, Iraq, suggests that breast cancer has been increasing at a significant pace in recent years. This study aimed to measure the current level of risk of breast cancer among females in Basrah and to describe the time trend over almost a decade of years. Data on breast cancer cases from all sources of cancer registration in Basrah governorate were compiled for the years 2005-2012. The data for each year were first checked separately for duplicate reporting of cases among various sources. Then the eight files were pooled together and checked again for any duplicate cases among years of registration. The final set of data contained 2,284 cases of breast cancer (2,213 female cases and 71 male cases). All patients were inhabitants of Basrah governorate at the time of diagnosis. Figures on the Basrah population were obtained from various sources including the Ministry of Health, Ministry of Planning and Developmental Collaboration and local household surveys. It was possible to have total population estimates for each year and by age and sex. The data were imported into SPSS (version 17) software. Age specific and year specific incidence rates were calculated. The age standardized incidence rate was also calculated using world population as the standard population to be 34.9 per 100,000 females. Age-wise, no case was reported among children aged less than 15 years and the incidence increased with advancing age reaching a peak of 123.8/100,000 females at the age range of 50-54 years. The time trend of the crude incidence rate showed only modest increased risk with passage of years and no age shift could be documented in this study. Breast cancer in females in Basrah is a significant health problem. The current incidence rate (crude, 23.7/100,000, age-standardized, 34.9/100,000) is high and justifies intensive efforts to improve early detection of cases, provide better treatment amenities and introduce long term preventive measures. Using the age standardized incidence rate as reported in this paper, it is possible to put the risk in Basrah within a regional and international context.

• Journal of Preventive Medicine and Public Health
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• 제41권5호
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• pp.300-306
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• 2008

Objectives : This study was performed to compare the standardized mortality ratios among different small areas and to explore the usefulness of standardized mortality ratios in South Korea. Methods : To calculate the standardized mortality ratio (SMR), we obtained the national deaths certificate data (2004-2006) and national registration population data (2003-2006), and these were provided by the National Statistical Office. The small areas (Eup.Myoun.Dong) were based on the subdivisions of counties. Among the 3,580 small areas classified by the National Statistical Office, 3,571 areas were included in this study. The basic statistics and decile distributions of the SMRs for all the regional levels were calculated, and the small area maps were also produced for some selected regions. To evaluate the precision of SMR, we calculated the 95% confidence intervals of the SMR in selected small areas. Results : The mean and the standard deviation of the SMRs among all small areas were 100.8 and 17.0, respectively. The range was 30.6-211.7 and the inter-quartile range was 20.7. Seoul metropolitan city displayed the lowest mean SMR among 16 regions in South Korea, and 34.6 percent of the small area SMRs belonged to the first decile(the lowest group). On the contrary, the mean SMR of Gyeongsangnam province was highest, and 26.1 percent of the small area SMRs belonged to the tenth decile(the highest group). In some areas, the precision of the SMR, which was calculated by the 95% confidence intervals, remained questionable, yet it was quite stable for almost areas. Conclusions : The standardized mortality ratios can be useful for allocating health resources at the small area level in Korea.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7517-7522
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• 2013

Background: Cancer incidence rates are increasing particularly in developing countries. It is crucial for policy makers to know basic cancer epidemiology in each region to design comprehensive prevention plans. There have hitherto been no population-based data available for cancer in Khuzestan province. The present report is a first from the regional population-based cancer registry for the period of 2002-2009. Materials and Methods: Data were collected retrospectively reviewing all new cancer patients whom were registered in Khuzestan province cancer registry during an 8-year period (2002-2009). All cases were coded based on the ICD-O-3 coding system and collected data were computerized using SPSS (Chicago, IL) software, version 11.5. The age standardized incidence rates (ASRs) per 100,000 person-year for all cancers were computed using the indirect method of standardization to the world population. Results: During the 8-year study period, 16,801 new cancer cases were registered. Based on the computed ASRs, the five most frequent malignancies in females were breast (26.4 per 100,000), skin (13.6), colorectal (5.72), stomach (4.31) and bladder(4.07) and in males, the five most frequent were skin (16.0 per 100,000), bladder (10.7),prostate (7.64), stomach (7.17), and colorectal (6.32).The ASR for all malignancies in women was 92.5 per 100,000, and that for men was 87.4. Conclusions: The observed patterns from the analysis of Khuzestan cancer registry data will lead to better understanding of the epidemiology of various malignancies in this part ofthe country and consequently provide a useful guide for authorities to make efficacious decisions and policies about a cancer control program for south-west Iran.

• 응용통계연구
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• 제19권1호
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• pp.57-67
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• 2006

표본조사에서 무응답은 여러 가지 이유로 발생하며, 이 때 응답자들의 정보로만 분석을 실시한다면 편향된 결과를 산출할 수 있어 보조변수를 이 용한 많은 무응답 대체 방법들이 연구되고 있다. 만일 결측자료 대체를 위한 보조변수들이 충분하지 않고 응답자들과 무응답자들 사이에 지역적 상관관계가 존재한다면 이를 결측자료 대체(missing data imputation)에 이용 할 수 있을 것이다. 본 논문에서는 2002년 강원지역의 농가경제 자료를 예제로 하여 공간상관을 이용한 무응답 대체 방법을 살펴보았으며, 공간상관이 존재할 경우 공간 대체 방법이 효율적임을 확인하였다.

• Journal of Gastric Cancer
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• 제16권3호
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• pp.152-160
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• 2016

Purpose: Endoscopic diagnosis of gastric cancer (GC) that emerges after eradication of Helicobacter pylori may be affected by unique morphological changes. Using comprehensive endoscopic imaging, which can reveal biological alterations in gastric mucosa after eradication, previous studies demonstrated that Congo red chromoendoscopy (CRE) might clearly show an acid non-secretory area (ANA) with malignant potential, while autofluorescence imaging (AFI) without drug injection or dyeing may achieve early detection or prediction of GC. We aimed to determine whether AFI might be an alternative to CRE for identification of high-risk areas of gastric carcinogenesis after eradication. Materials and Methods: We included 27 sequential patients with metachronous GC detected during endoscopic surveillance for a mean of 82.8 months after curative endoscopic resection for primary GC and eradication. After their H. pylori infection status was evaluated by clinical interviews and $^{13}C$-urea breath tests, the consistency in the extension of corpus atrophy (e.g., open-type or closed-type atrophy) between AFI and CRE was investigated as a primary endpoint. Results: Inconsistencies in atrophic extension between AFI and CRE were observed in 6 of 27 patients, although CRE revealed all GC cases in the ANA. Interobserver and intraobserver agreements in the evaluation of atrophic extension by AFI were significantly less than those for CRE. Conclusions: We demonstrated that AFI findings might be less reliable for the evaluation of gastric mucosa with malignant potential after eradication than CRE findings. Therefore, special attention should be paid when we clinically evaluate AFI findings of background gastric mucosa after eradication (University Hospital Medical Information Network Center registration number: UMIN000020849).

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5493-5498
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• 2015

Due to the lack of nationwide population-based cancer registration, the total cancer prevalence in Iran is unknown. Our previous work in which we used a basic network scale-up (NSU) method, failed to provide plausible estimates of total cancer prevalence in Kerman. The aim of the present study was to estimate total and partial prevalence of cancer in southeastern Iran using an adapted version of the generalized network scale-up method. A survey was conducted in 2014 using multi-stage cluster sampling. A total of 1995 face-to-face gender-matched interviews were performed based on an adapted version of the NSU questionnaire. Interviewees were asked about their family cancer history. Total and partial prevalence were estimated using a generalized NSU estimator. The Monte Carlo method was adopted for the estimation of upper/lower bounds of the uncertainty range of point estimates. One-yr, 2-3 yr, and 4-5 yr prevalence (per 100,000 people) was respectively estimated at 78 (95%CI, 66, 90), 128 (95%CI, 118, 147), and 59 (95%CI, 49, 70) for women, and 48 (95%CI, 38, 58), 78 (95%CI, 66, 91), and 42 (95%CI, 32, 52) for men. The 5-yr prevalence of all cancers was estimated at 0.18 percent for men, and 0.27 percent for women. This study showed that the generalized familial network scale-up method is capable of estimating cancer prevalence, with acceptable precision.

• 한국정보과학회논문지:정보통신
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• 제31권2호
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• pp.146-157
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• 2004

이동 사용자에게 지속적인 서비스품질 보장을 제공하기 위해서는 일반적으로 사용자 방문할 것으로 예상되는 지역에 사전에 중복적으로 자원을 예약하는 방안을 사용한다. 이와 같은 방식에서 관건이 되는 문제는 중복적 자원 예약에 의한 자원 낭비를 줄이면서도 서비스품질 보장의 연속성을 유지하는 것이다. 본 논문에서는 지리적으로 인접한 두 개의 무선 네트워크 도메인 사이에 두 도메인에 모두 속하는 그레이 셀을 두는 무선 네트워크 구조를 제안하고, 이를 이용하여 무선 네트워크에서의 중복적인 자원 예약을 완전히 제거하면서도 도메인 간 이동으로 인한 일시적 자원 예약 단절을 크게 줄일 수 있는 방안을 제안하였다. 시뮬레이션을 통하여 제안한 방안은 도메인 간 이동이 발생하는 경우에도 도메인 내에서 이동 할 때와 유사한 성능을 보이며, 예약 단절 시간이나 패킷 손실율면에서 기존의 방법보다 훨씬 나은 성능을 제공함을 볼 수 있었다.