메모리 공유형 다중 프로세서의 동기화를 위한 Spin-Lock 기법의 성능 분석

홍춘표,이종임,남상균 대구대학교 과학기술연구소 1997 科學技術硏究 Vol.4 No.3

Most of the shared-memory multiprocessor system provide a hardware primitive for supporting mutually exclusive accesses to shared data. The hardware primitive consists of instructions that atomically read and write a single memory location. When a processor is accessing a shared data, the lock is set to busy, and other processors must wait until the lock is released. This paper analyse the characteristics of four spin-lock alternatives, and compare the performance of the proposed scheme through the simulation on shared-memory multiprocessor (Sequent-Balance). The simulation results show that all the spin-lock alternatives for synchronization degrade overall performance as the number of spinning processors increases. In addition, a variant of Ethernet backoff scheme shows good performance even for large numbers of spinning processors. Because of its simplicity, backoff scheme has better performance when there is no contention for the lock.

農家副業으로서의 畜産現況과 그 改善方案에 關한 硏究

洪鐘旭,李熙碩,朴恒均,崔源弼,李鉉凡,金祥基 慶北大學校 1978 論文集 Vol.25-26 No.-

Recently, there have been much corncerns about the strategies which can reasonably increase farm income at the average farm level. In other words, as a result of third-term Five Year Economic Development Plan there was a remarkable gap between farm household and non-farm household incomes. Therefore, various policy tasks to eliminate this unbalanced income growth are currently being implemented. This study was carried out to identify the situation of livestock farming at general farm level, regarded as one of income generation strategies for the farm sector. Some results of the study can be summarized as follows: First of all, it was found that a group of farms which raise a small size of animals like Korean cattle, hog, and various poultry gave higher resource bases as compared with that of non-livestock farms. Secondly, it was also recognized that both farm and farm household income levels of small-scale livestock farms were higher than those of non-livestock farm group within the same region, specifically as much as approximately ￦200,000. Thirdly, it was known that the average size of animal raising per household in 0.9 head of cattle, 0.8 head of hog, and 34 lyers of poultry, respectively. To the end, according to the farm disposal practices of major by-products, only about 18 percent of total rice straws produced at individual farms was utilized for the animal raising, and about 45 percent of all the brans available at farms for the livestock enterprise. The rest of straw and brans in regarded as selling at farm level. In this respect, it may be recommended either to increase current size of animals or to expand number of livestock farms.

실리카 다중 모드 간섭기를 이용한 상향 비대칭 1.31/1.55m 파장 여과기 분석

홍종균,이승대 남서울대학교 공학연구센터 2003 공학연구 Vol.4 No.-

A novel 1.31/1.55μm silica based wavelength filter using multi-mode interference (MMI) coupler was developed. To design a compact device size, the wavelength filter is optimized to received signal which is from a fiber and has 1.55μm-wavelength. Because 1.31μm-wavelength transmitted signal can be amplified before transmission, it can be valuable to have output intensity of more than 60% for transmitted signal. The wavelength filter is designed using MMI coupler to achieve a compact, tolerant, and polarization independent optical device. The filter is fabricated by commercially available technology for Ge-doped SiO_(2) waveguide on Si substrate. For small dimensional optical device, 1.2% index difference between core and clad is used. Consequently, excess loss is 0.18dB, extinction ratio is 18.7dB, and PDL is 0.26dB at 1.55m, excess loss is 5.22dB, extinction ratio is 3.18dB, and PDL is 0.32dB at 1.31m for the wavelength filter.

GMM을 이용한 환경선호도 추정

김홍균,임종수,고윤희 한국환경경제학회 한국자원경제학회 2003 자원·환경경제연구 Vol.12 No.1

The main purpose of this paper is to estimate environmental preference of advanced countries for water and air pollution. In doing so, we introduce home production. That is, we assume that pollution has not only negative effect on utility but also positive effect on production, Thus if the former is greater that the latter effect, the total effect of pollution is negative. In this paper, we investigated this effect of advanced countries by using GMM estimator. The main finding is that in case of air pollution. This effect is negative. This implies that in case of air pollution, the disutility effect is greater that productivity effect.

악골에 발생한 악성 섬유성조직구종 2례

정종철,최홍란,오희균,박준아,류선열,이종호,김영운,정숭룡 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.3

Malignant fibrous histiocytoma rarely occurs in the jaws. Although the histogenesis of this tumor remains controversal, it is best regarded as a primitive and pleomorphic nature reflected by collagen production and occasional phagocytosis. It is common for metastatic foci to appear in lung and regional lymph node. There are variable treatments such as radiotherapy, surgical excision or combination, therapy of surgical excision, chemotherapy and radiotherapy. With the review of literatures, the authors report the clinical study of two cases of malignant fibrous histiocytoma of the jaw.

일부 부인과 양성 질환자의 지방조직 및 혈청의 PCBs와 DDE 농도

박성균,이강숙,노영만,구정완,민선영,한진구,고원경,김미란,정재근,이종승,김진홍 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목적 : 본 연구는 지방조직과 혈청의 PCBs와 DDE 농도를 측정하고, 이에 영향을 미치는 것으로 알려진 요인들과의 관련성을 평가하고자 하였다. 방법 : 유방암, 자궁내막증 등 유기염소계 화합물의 영향이 있는 것으로 알려진 호르몬 관련 질병을 제외한 부인과 환자 52명을 대상으로 지방조직과 혈청을 분석하였으며, 설문조사를 통하여 연령, 교육수준, 직업, 비만도, 흡연과 음주, 출산력, 수유력등을 조사하였다. 지방조직과 혈청의 PCBs와 DDE 농도는 가스크로마토그래피를 사용하여 측정하였다. 결과 : 지방조직의 경우, 13개 PCBs congeners 농도의 합은 중앙값이 48.29 ng/g, 기하평균값이 56.78 ng/g이었고, DDE 농도는 중앙값이 142.89ng/g, 기하평균값이 117.06 ng/g이었으며, 혈청의 경우는 PCBs congeners 농도의 합은 중앙값이 4.67 ㎍/L, 기하평균값이 4.85 ㎍/L이었고, DDE 농도는 중앙값이 1.75 ㎍/L, 기하평균값이 2.09 ㎍/L로 나타났다. 지방조직과 혈청의 DDE 농도 사이는 높은 상관성을 보였으나(r²=0.310, p=0,0002), PCBs는 상관성이 약한 것으로 나타났다(r²=0.029, p=0.2582). 영향요인을 범주화한 후 로그변환 시킨 지방조직과 혈청의 PCBs, DDE 평균의 차이를 분석한 결과, 지방조직의 DDE만이 출산자녀수(p=0.015), 초산연령 (p=0.014), 비만지수(p=0.035)와 연관성이 발견되었다 다중회귀분석의 결과 지방조직의 DDE는 출산자녀수가 적을수록, 초산연령이 늦을수록 증가하는 경향을 보였다. 결론 : 출산자녀수와 초산연령, 비만도가 지방조직의 DDE와 관련성을 보였으며, 또한 유기염소계 화합물의 장기간의 노출에 의한 영향을 평가하는데 있어서 혈청보다 지방조직이 더 유용한 생물지표임을 알 수 있었다. Objectives : This study was purposed to determine the levels of PCBs and DDE in adipose tissue and serum and to evaluate the relations with factors affecting these levels. Methods : We analyzed adipose tissues and sera from 52 gynecologic benign disease patients aged 27-78 years, except hormonal diseases such as breast cancer and endometriosis. We also surveyed age, education, occupation, body mass index (BMI), smoking, drinking, number of children, and duration of breastfeeding by questionnaires. Tissue and serum levels of PCBs and DDE were measured using gas chromatography. Results : The median and geometric mean levels of PCBs were 48.29 ng/g, 56.78 ng/g for adipose tissue and 4.67 ㎍/L, 4.85 ㎍/L for serum, and those of DDE were 142.89 ng/g, 117.06 ng/g for adipose tissue and 1.75 ㎍/L, 2.09 ㎍/L for serum, respectively. Adipose tissue and serum levels for DDE showed high correlation (r²=0.310, p=0.0002), but those of PCBs didn't (r²=0.029, p=0.2582). In analyses of the differences of the means of log transformed adipose tissue and serum PCBs and DDE levels for groups of potential covariates, only adipose tissue DDE levels were significantly associated with number of children (p=0.015), age at first birth (p=0.074) and BMI (p=0.035). In multiple regression analysis, adipose tissue DDE levels were significantly increased with decreasing number of children and increasing age at first birth. Conclusions : This study suggested that parity and adiposity were associated with levels of DDE in adipose tissue, and adipose tissue is a better biomarker than serum for evaluating the long-term exposure of organochlorines.

Increased expression of P53 and Bax in the spinal cords of rats with experimental autoimmune encephalomylitis

문창종,김승준,위명복,김희석,정종태,박전홍,지영흔,Tanumab, Naoyuki,Matsumoto, Yoh,신태균 濟州大學校 農科大學 動物科學硏究所 2000 動物科學論叢 Vol.15 No.1

The expression of pro-apoptotic molecules, p53 and Bax, in the spinal cord of rats with experimental autoimmune encephalomyelitis (EAE) was examined. Apoptosis was confirmed by the terminal deoxynucleotidyl transferasemediated dUTP nick end-labeling (TUNEL) method. TUSEL (+) apoptotic cells were mainly either ED1 (+) macrophages or T-cells in the parenchyma of E N . Western blot analysis showed that both p53 and Bax expression significantly ( p < 0.01) increased in the spinal cords of EAE rats at the peak stage, and thereafter declined. An immunohistochemical study showed that inflammatory cells (notably T cells) in the parenchyma express p53 and Bax, while brain cells, includng neurons and glia, were devoid of these nuclear staining of these molecules. The nuclear expression of p53 largely matches apoptotic cells in the parenchyma of EAE. These finchngs suggest that pro-apoptotic molecules, p53 and Bax, may play an important role in eliminating T cells in the parenchyma in EAE.

Streptococcus constellatus에 의한 경막 외 농양이 동반된 화농성 척추염 1예

안홍대,박재찬,서종구,김진용,김수연,박윤수,서일혜,조용균 대한감염학회 2008 감염과 화학요법 Vol.40 No.5

We report a case of vertebral osteomyelitis with epidural abscess caused by Streptococcus constellatus. The patient was present with fever, back pain, and dyspnea for 1 week. The patient was previously healthy and did not have any predisposing factor. After evaluation, the patient was diagnosed as Streptococcus constellatus vertebral osteomyelitis. He was successfully treated with surgical debridement and antibiotic therapy. To the best of our knowledge, this is the first case of S. constellatus vertebral osteomveltis with epidural abscess to be reported in Korea.

Osteotome Sinus Floor Elevation Procedure를 이용한 임프란트 매식

송종운,조용기,박홍주,김영운,오희균,유선열 대한악안면성형재건외과학회 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.2

Maxillary sinus has an anatomic limitation to bone support available for dental implant. When there is less than 10㎜ of bone remaining between the upper alveolar ridge crest and the maxillary sinus floor, bone augmentation should be considered. In 1994, Summers reported two sinus floor elevation techniques of limmediate implant insertion, using osteotomes, for patients who have at least 5㎜ of bone remaining between the alveolar ridge crest and the maxillary sinus floor. One technique is osteotome sinus floor elevation (OSFE) procedure in which uses osteotomes to elevate the sinus floor. The other is bone-added OSFE (BAOSFE) procedure in which bone graft is added into osteotomy site. Both procedures conserve all of the remaining bone and selectively displace it upward, thereby raising sinus floor. This study was aimed to evaluate the long-term success rate of implants which had been placed by osteotome sinus floor elevation procedure. Between February 1996 and June 1998, 10 implants were placed using OSFE or BAOSFE procedures in 6 patients who had at least 6㎜ of bone remaining between the alveolar ridge crest and the sinus floor. OSFE procedures were performed in patiens, 2∼4㎜ sinus floor elevation was needed, whereas BAOSFE procedures were done in patines, more than 4㎜ sinus floor elevation was needed. During the mean follow-up period of 4 years 4 months (3 years 6 months ∼ 5 years 9 months), no implant was failed and all patients showed good functional results. OSFE and BAOSFE procedures seemed technically easier and less invasive compared to conventional sinus lift procedure. And both procedure have good success rate.

환경관련 R&D사업 운영체계의 문제점과 개선방안 : 설문조사를 중심으로 A Survey Study

김홍균,임종수 한국환경경제학회 한국자원경제학회 2004 자원·환경경제연구 Vol.13 No.3

환경 R&D 예산의 효율성 제고 방안의 연구를 위해 전주기방법에 입각하여 환경 R&D 사업의 운영체계에 대한 문제점과 개선방안을 제시하였다. 연구결과 크게 네 가지 부문의 개선 노력이 요구되는 바, 첫째, 기술현황에 관한 기초자료를 축적·관리하는 전담조직의 운영, 둘째, 주기적 기술수요조사를 통한 과업선정체계의 강화, 셋째, 국가연구 개발사업으로 추진된 개발기술의 상용화 자금지원제도에 대한 홍보·알선 업무의 강화, 그리고 마지막으로 이전기술의 사업화를 위한 지원기관, 대상사업 및 재정지원의 확대가 가장 필요한 것으로 결론지어졌다. 그러나 R&D 지원사업의 운영체계에만 국한하여 분석한 본 연구의 한계를 극복하기 위해서는 R&D 사업의 전반에 관한 포괄적인 추후 연구를 추진할 필요가 있다. Environmental R&D management system has been analyzed with LCA method. Based on the analysis, we found the following four elements were essential for improving effciency of environmental R&D management system: establishment of an information clearinghouse that collects and distributes information on the status of the domestically owned environmental technology. Periodic survey of the environmental technology demand to give guidance in selecting the environmental R&D project that are to be subsidized, dissemination of information on the technology transfer and commercialization assistance program, and increased funding as well as the expansion of project categories eligible for R&D subsidy.