• Journal of Communications and Networks
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• 제11권2호
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• pp.104-114
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• 2009

In this paper, a technique is proposed that enables secondary users to evaluate channel availability in cognitive radio networks. Here, secondary users estimate the utilization of channels via predicting the traffic pattern of primary user, and select a proper channel for radio transmission. The proposed technique reduces the channel switching rate of secondary users (the rate of switching from one channel to another) and the interference on primary users, while maintaining a reasonable call blocking rate of secondary users.

• Journal of Preventive Medicine and Public Health
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• 제17권1호
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• pp.31-36
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• 1984

In order to know about the utilization of health subcenter in a Korean rural community, a study was carried out through analyzing the records on the outpatients in Su-Dong Health Subcenter during 5 years from 1978 to 1982, and the following results were obtained. 1. The annual utilization rate of health subcenter of Su-Dong Myun showed decreasing tendency such as 946.6 in 1978, 886.4 in 1979, 736.5 in 1980, 708.3 in 1981 and 609.1 in 1982 per 1,000 people. 2. In terms of annual utilization rate of health subcenter by sex, utilization rate of female was higher than that of male such as in 1978 (male 908.6, female 986.3), 1979 (male 819.2, female 956.7) and 1981 (male 686.0, female 731.5) except 1980(male 790.0, female 683.3) and 1982(male 632.7, female 585.0). 3. Every year the 5 major diseases of the new patients cared in health subcenter were the same as follows; Diseases of the Respiratory System, Diseases of the Digestive System, Diseases of the Skin and Subcutaneous Tissue, Accident Poisoning and Violence, and Diseases of the Nervous System and Sensory Organ. 4. In terms of annual utilization rate of health subcenter by age, utilization rate of $0{\sim}4$ year group was highest every year such as 3,666.0 in 1978, 3,232.5 in 1979, 2,819.0 in 1980, 2,361.4 in 1981 and 2408.7 in 1982 per 1,000 people. 5. The average visiting times per case to health subcenter were not much different every year such as 1.75 times in 1978, 1.79 times in 1979, 1.69 times in 1980, 1.79 times in 1981, and 1.80 times in 1982. 6. The monthly utilization rates per 1,000 people of health subcenter had two peaks in February(40.9 in 1980 and 86.4 in 1981) and July(84.6 in 1980 and 72.1 in 1981) except 1982. 7. The distribution of new patients by the source of medical fee payment was follows; community health organization member 86.9%, medicaid program 6.5%, and medical insurance 6.6% in 1980 and community health organization member 76.8%, medicaid program 11.4%, and medical insurance 11.8% in 1981 and community health organization member 78.2%, medicaid program 14.8% and medical insurance 13.2% in 1982.

• 한국통신학회논문지
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• 제24권9A호
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• pp.1359-1371
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• 1999

본 논문에서는 기존의 폭주 회피형 명시율 트래픽 (Explicit Rate feedback) 스위치 알고리즘의 단점을 개선하여 버퍼의 수위와 변화율에 따라 동적으로 목표 이용률을 조장하여 링크 이용 효율을 향상시킨 효율적인 명시율 피드백 스위치 알고리즘을 제안하였다. 그리고, 시뮬레이션을 통하여 기존의 대표적인 명시율 피드백 스위치 알고리즘인 ERICA 스위치와 NIST 스위치의 성능을 분석하고, 제안된 명시율 피드백 스위치 알고리즘과 비교하였다. 시뮬레이션 결과 제안된 ER 피드백 스위치는 동적인 목표 이용률의 조정을 통하여 가용 대역폭의 변화에 빠른 전송률의 변화를 보였으며, 스위치의 최대 큐 길이를 줄여 버퍼 범람을 방지하면서도 매우 높은 링크 이용 효율을 보여 성능이 개선됨을 알 수 있었다.

• Ocean and Polar Research
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• 제38권3호
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• pp.195-207
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• 2016

Because the high latitude region in the North Pacific is characterized by high primary production in the surface water enriched with nutrients, it is important to understand the variation of surface water productivity and associated nutrient variability in terms of global carbon cycle. Surface water productivity change or its related nutrient utilization rate during the Northern Hemisphere Glaciation (NHG; ca. 2.73 Ma) has been reported, but little is known about such circumstances under gradual climate cooling since the NHG. Bulk nitrogen isotope (${\delta}^{15}N_{bulk}$) of sedimentary organic matter has been used for the reconstruction of nutrient utilization rate in the surface water. However, sedimentary organic matter experiences diagenesis incessantly during sinking through the water column and after burial within the sediments. Thus, in this study we examine the degree of nitrate utilization rate during the early Pleistocene (2.4-1.25 Ma) since the NHG, using the diatom-bound nitrogen isotope (${\delta}^{15}N_{db}$), which is known to be little influenced by diagenesis, from Site U1343 in the Bering slope area. ${\delta}^{15}N_{db}$ values range from ~0.5 to 5.5‰, which is lower than ${\delta}^{15}N_{bulk}$ values, but they vary with larger amplitude. Variation patterns between ${\delta}^{15}N_{db}$ values and biogenic opal concentration are generally consistent, which indicates that the nitrate utilization rate is closely related to opal productivity change in the surface water. A positive correlation between opal productivity and nitrate utilization rate was observed, which is different from the other high latitude regions in the North Pacific. The main reason for this contrasting relationship is that the primary production in the surface water at Site U1343 is influenced mostly by the degree of sea ice formation. Still, although concerns about diagenetic alteration have been avoided by using ${\delta}^{15}N_{db}$, the effects of the preservation state of biogenic opal and the species-dependent isotopic fractionation on ${\delta}^{15}N_{db}$ should be assessed in the future studies.

• 농촌의학ㆍ지역보건
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• 제29권1호
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• pp.195-206
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• 2004

충남도내 18개 도서지역의 의료 이용행태와 의료이용을 결정하는 요인을 알아보기 위해 2002년 9월 9일부터 9월 18일까지 조사한 결과는 다음과 같다. 조사대상자의 외래 의료이용 횟수는 연령이 높을수록, 교육수준이 낮을수록 많았고 주관적 건강상태가 나쁠수록 의료이용 횟수가 높았고 통계적으로 유의하였다(p<0.05). 유병 만성질환수가 많을수록 외래 의료이용이 많았고, 의료기관 접근시간이 2시간이상 3시간 미만인 군에서 외래 의료이용 횟수가 높게 나타났다(p<0.05). 의료기관 입원 횟수는 상용치료원이 종합병원인 군에서 가장 높게 나타났고 통계적으로 유의하였다(p<0.05). 의료기관의 입원 횟수에 영향용 미치는 변수로는 주관적 건강상태로 나타났으나(p<0.05) 그 설명력이 미약하였다.

• 보건행정학회지
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• 제2권1호
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• pp.147-166
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• 1992

The purpose of this study is to analyze the effects of the health center hospital on the health service utilization pattern of the rural population in a county. Two field studies had been conducted in Yonchon County, Kyunggi Province, on February 1989 and on August 1991 before and after the establishment of the Yonchon health center hospital. This study revealed that Yonchon health center hospital occupied 7.3% of total outpatient visits and 16.8% of hospitalization of the county population and the self-sufficient rate of the outpatient visit and hospitalization of Yonchon County between two field studies increased by 1.7% and 20.9% each. Yonchon health center hospital contributed to the growth of the public health sector but it weakened the role of health sub-centers. For the efficient health service utilization of the population in that County, more investment to health center hospital would be needed and the primary health activities of the health subcenter should be enforced.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권3호
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• pp.1113-1135
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• 2018

Existing trust evaluation models for wireless sensor networks can accurately and objectively evaluate trust value of nodes, but the nodes' energy saving problem was ignored. Especially when there are a few malicious nodes in a network, the overall trust value calculation for all nodes would waste lots of energy. Beside that, the network failure caused by nodes death was also not considered. In this paper, we proposed a method for avoiding energy hole which applied trust evaluation models and a trust evaluation method based on information entropy, so as to achieve the purpose of improving nodes utilization. Simulation results show that the proposed method can effectively improve nodes utilization, and it has reasonable detection rate and lower false alert rate compared to other classical methods.

• 대한안전경영과학회지
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• 제4권4호
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• pp.129-136
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• 2002

Utilization rate for the restrictive gate and required time and walking distance to board are to be a measure for the gate management and passenger's convenience estimation. So, the main purpose of the gate management are maximization of utilization rate and increment of airport terminal user's convenience through the efficient gate management. This study intends to maximize the utilization rate on usable gates and minimize the passenger's working distance in terminal by concerning about layout, terminal configuration, local passenger of the airport and formulate the gate assignment problem with integer linear programming problem. Then we obtained solution using optimization software LINGO and analyzed that maximize the number of assignment flights and minimize the passenger's walking distance.

• Journal of Preventive Medicine and Public Health
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• 제19권1호
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• pp.137-145
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• 1986

A Nationwide health care utilization survey was conducted from March 11 to September 19, 1985 to assess the level of illness and the magnitude of medical care utilization. A probability sample of 15,427 persons was taken from 180 Enumerated Districts designated by the Economic Planning Board. Of those 4,500 housewives were proxy respondents. A interview was conducted with pre-tested questionnaire schedule which was recorded by well trained interviewers. Age and sex compositions of the study population were similar to those of general population structure in 1985. The major findings of this survey are as follows : 1) A total of 64.5% of the study population lived in city area and 35.5% lived in county area. 2) While no difference was observed in interview rate between city and county area, it showed statistically significant difference in the medical security program coverage rate between the two areas(44.7% and 37.1%, respectively) 3) Morbidity rate was 79 per 1,000 persons during the two week periods. There was difference in age and sex adjusted morbidity rates between city and county area. Furthermore morbidity rates by the status of the program were significantly difference between the two areas. 4) Average ambulatory care utilization rate was 7.2 visits per person per year and average admission rate was 1.8 per 100 persons per year. There was significant difference in average ambulatory care utilization rate by the program. but no significant difference in medical utilization rate between city and country area. 5) The major symptoms of the perceived illness was the respiratory system(44.1%). 6) A total of 50.4% of the perceived illness among the covered group by the program were treated at the hospital and clinics, but those who are not covered used primarily drug stores(61.3%).

• Journal of Preventive Medicine and Public Health
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• 제30권4호
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• pp.764-778
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• 1997

근로자의 요통으로 인한 의료보험 이용 실태를 파악하기 위해 1993년부터 1995년까지 광주의 한 직장 의료보험조합에 소속된 남자 8,783명, 여자 1,400명계 10,153명의 의료보험 급여자료로부터 한국표준질병사인 분류코드상 요통과 관련된 변형성 배병증, 기타 배병증, 요추염좌에 해당되는 질환군의 치료시 이용한 의료보험 급여자료와 연구대상자의 일반적 특성을 결합시켜 분석한 결과는 다음과 같다. 1. 1993년부터 1995년까지 3개년간 연구대상자의 요통으로 인한 수진율은 남자 17.1%, 여자가 19.4%였으며, 요통의 원인중 남녀 모두 '기타 배병증'이 가장 많은 비율 차지하였다. 2. 남녀 모두에서 연령 및 입사시 연령이 높을수록 요통으로 인한 수진율이 증가하는 경향이 있었다(p<0.001). 남녀 모두 근무기간이 길수록 수진율이 증가하는 경향을 보였으나, 통계적 유의성은 없었다. 남자에서는 시멘트 콘크리트제품 제조업 종사자가 유의하게 수진율이 높았으며(p<0.01), 여자에서는 생산직이 사무직보다 유의하게 높았다(p<0.01). 3. 1993년부터 1995년까지 3개년간 요통의 수진율과 요통으로 인한 새로운 수진자의 발생율은 비슷하였지만, 세부적으로 남녀 모두에서 기타 배병증이 증가하는 경향이 있었다. 4. 수진량에 있어서는 연령별, 근무기간별, 산업별, 소득수준에 따라 수진자 1인당 평균외래수진건수에 있어서 유의한 차이가 있었고(p<0.05), 근무기간별로 수진자 1인당 평균외래방문회수가 유의한 차이를 보였다.(p<0.05). 이상을 종합해보면 매년 요통으로 인한 의료보험 이용자수가 증가하고 있으며, 특히 만성적인 장애를 유발하는 추간판탈출증을 포함하고 있는 '기타 배병증'이 현저하게 증가하고 있는 경향을 볼 때 산업장에서 효과적인 요통예방 및 관리 사업이 요구된다 하겠다.