실리카흄을 흔입한 고강도 콘크리트 개발

홍창우,김태경,김경진,김성환,김남윤,심도식,이정호,윤청호,백민경,원치문,박제선,이주형,정경일 강원대학교 석재복합신소재제품연구센터 1996 석재연 논문집 Vol.1 No.-

콘크리트 구조물이 대형화됨에 따라 설계단면이 증대되어 상대적으로 많은 경제적 손실을 부담하게 된다. 따라서 단면을 감소시키면서도 소요의 하중에 안전한 구조물을 건설하기 위해서는 우선적으로 구조물 건설에 기초가 되는 고품질, 고내구성의 고강도 콘크리트 개발이 절실히 요구된다 본 연구에서는 일정 시멘트비 및 혼화재 비율하에서 소요의 워커빌리티가 확보되는 고강도 콘크리트를 시간과 온도의 변화에 따라 증기 양생하여, 압축, 인장, 휨강도 뿐만 아니라 파괴특성을 실험적으로 연구하였다. 시료 제작시 시멘트 입자 사이의 공극 및 불연속 영역을 충전하여 고밀도화하기 위한 콘크리트용 혼화재로 시멘트 비표면적이 상당히 작은 초미립 분말인 실리카흄을 이용하였다. 또한 AE감수제 및 고성능 유동화제를 사용하여 혼화재의 첨가에 의하여 발생될 수 있는 워커빌리티의 감소를 방지하였다. 실험결과에 의하면 일정 양생 지속 시간하에서 온도의 증가에 따라 콘크리트의 압축, 인장 및 휨강도가 전반적으로 증가하였다. 동일하게 일정 온도하에서 양생 지속시간이 커짐에 따라 강도들이 증가됨을 알 수 있었다. 따라서 상대적으로 높은 온도와 긴 지속 양생 조건하에서 파괴에 대한 저항력이 크게 나타났다. The compressible, tensible, and flexibleresistance of the high strength concrete is analyzed by the experimentation in the present study. For the test, we cure several samples with the silica fume as a mixture being become dense the spaces between the particle of cement under the variation of both the temperature and the curing-interval. Then, the superplasticizer and the ezcon are also used to satisfy the required workability for construction. The compressible, tensible, and flexible resistances to a stress are increased as increasing the temperature and the time interval for the curing. Therefore it is concluded that the overal fractural and mechanical properties is improved by mixing the silica fume into the cement.

비만을 동반한 위암 환자에서 두 병을 같이 수술 치료한 경험(증례)

최경현,윤기영,문형환,신연명,서경원,안수미,송윤미,석정희,정경연,이은하 고신대학교의과대학 2008 고신대학교 의과대학 학술지 Vol.23 No.3

Obesity is growing problem in Korea. We had a case of bariatric surgery during gastric cancer operation. Patient was 29 year old Korean lady with early gastric cancer located in the lesser curvature side of the middle 1/3 of the stomach. Her body weight was 89 kg, height 163 cm, and thus body mass index was 33.5 kg/m2. Preoperative blood pressure was 130/90 mmHg, hemoglobin 12.9 g/dL, total lymphocyte count 3,280/mL, serum albumin 4.3 g/dL, CEA 1.1 ng/mL, CA 19-9 9.1 ng/mL, and alpha fetoprotein 2 ng/mL. Another associated disease was right thyroid follicular neoplasm. The chest X-ray was normal. After IM injection of 2,500 units of heparin 30 minutes before the induction of general anesthesia, she received curative subtotal gastrectomy and Roux en Y gastrojejunostomy when a malabsorption loop of 120 cm jejunum was incorporated between the Treitz ligament and the end to side jejuno-jejunostmy site at May 29th 2006. Her postoperative course was uneventful except a minor wound seroma and the elevations of serum amylase(up to 4 folds) and lipase(up to 2 folds). She lost her body weight 9 kg in 5th, 21 kg in 7th, and 27 kg in 10th postoperative months to became 61.5 kg. On follow up exams in July 2008, she gained 4 kg to overcome her weakness and fatigue. From the above result, the incorporation of a malabsorption loop during reconstruction phase of gastric cancer operation was a good option for obese gastric cancer patients especially in cases of early gastric cancer.

경유교환기 수의 제약을 고려한 패킷 통신망 설계에 관한 연구

윤문길,주성순,전경표 한국경영과학회 1995 經營 科學 Vol.12 No.2

Traditionally, the scarce and expensive resources in communication networks has been the bandwidth of transmission facilities; accordingly, the techniques used for networking and switching have been chosen so as to optimize the efficient use of that resource. One of them is the packet switching for data communications, which is much different from the circuit switching. It allows multiple users to share the data network facilities and bandwidth, rather than providing specific amounts of dedicated bandwidth to each users. One main challenge therefore has been to design and build cost-effective packet switching networks. In this paper, we develop a mathematical programming medel and heuristic algorithm for designing the packet switching networks with hop-count constraints. To develop an efficient heuristic, we apply the Lagrangian relaxation method. Some valid inequalities, which have been known as the tight constraints, are considered to improve the bound for Lagrangian sub-problem. The computaional experiments show that the performance of the proposed heuristic is very satisfactory in both the speed and the quality of design solutions generated.

Interleukin-1β에 의한 사람 정상 코점막 상피세포의 분비기능 및 형태 변화

김경수,윤주헌,최진우,이정권,문형진,박준호,전희선 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.11

중이, 외이도 및 측두하와에 국한된 편평상피유두종 1예

윤병문,박성원,민경식,홍기수,조미연,양석우 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.7

구속운동을 받는 외팔보의 혼돈진동

최봉문,류봉조,윤충섭,임경빈 大田産業大學校 2000 한밭대학교 논문집 Vol.17 No.1

When the motion of vibrating structure is restrained by the adjacent objects, its vibration frequencies and mode shapes are changed. In general, the vibration characteristics of the system becomes unpredictable. Although the importance of the study on this type of vibration model increases in many engineering areas, most studies conducted to date were focused to the theoretical study on dynamic responses of the structure with stops, including a few experimental works. Specially, the study on the nonlinear phenomena due to the impact between a structure and stops have been mainly performed theoretically. It is, therefore, desired to find a way to have a better understanding on the vibration characteristics caused by the impact of a structure to stops. In the paper, both numerical analyses and experiments are conducted for a fixed-free beam that is restrained by the stops at the free end. The chaotic vibration characteristics of the nonlinear motion and the dynamic response of the system are investigated and presented for various magnetic forces between stops.

노인의 갑상선기능저하증에 대한 임상적 연구

정윤석,남문석,이은직,김경래,이현철,김현승,허갑범 한국노화학회 1993 한국노화학회지 Vol.3 No.1

한국인의 정당관에 대한 실험적 고찰

조일문,윤경우 건국대학교 1970 學術誌 Vol.11 No.1

This article is prepared to serve the purpose of experimentally analyzing the nature and changes of Korean attitude toward political party in recent years. It is based on a sample study about political parties in Korea and analyses of relevant literatures and materials. The sample study had been conducted in a most selective way in view of the limited number of personnel, expenses and the pressure of time. In order to eliminate any bias or prejudice on the part of interviewers, however, special efforts had been made in selecting samples adequate enough to represent the sex, occupation, age, educational background and the compositive ratio among the population. The results of sample study on the basis of 1,002 respondents might be summarized as follows : 1. The necessity of political party is particularly emphasized by male population, urban residents, younger generation, intellectuals and propertied classes. Though in small number altogether, those who think political party unnecessary are found in a relatively greater number in urban areas than in rural areas. 2. There are now many political parties registered in Korea. The results of the survey about what group regards political system composed of how many political parties as most desirable are as follows ; two or three parties‥‥‥‥Supported by females, rural dwellers, the aged, the lower-educated. three or four parties‥‥‥‥Supported by males, urban residents and intellectuals. In general, the degree of recognizing the value of political parties is considerably high with regard to the two major parties, especially with regard to the government party. High degree of recognition for government party is attributable to the fact that the ruling party is in a position to penetrate deeply into the masses with the support of the government. Those who are more familiar with political party tend to insist upon the greater necessity of political party. But this has no direct bearing with the ruling that only party nominees can be candidates for the Presidency and the National Assembly membership, and that independents without party affiliation are prohibited from running as candidate. 3. In selecting Presidential candidates and National Assembly candidates, more emphasis is usually placed upon their personality and public pledges than upon their party affiliation. Respondents who synthetically considered the following three elements-political party, public pledges and personality-amounted to 36.7%. Among them, about 70% considered primarily in terms of personality. The degree in which continuous support to the same party is very low and this tendency seems to have something to do with Korean tradition of taking into serious consideration the personality itself rather than political party. 4. Half of the respondents are in favor of the measure that independents without party affiliation and consequently without party recommendation may become candidates for the member of National Assembly, while one-thirds of them are againt it. They think independents should be given opportunities to run as candidates for National Assemblymen. Though they admit the very necessity of political parties, they still seem to be of the opinion that corruptions accompanying party politics have to be dispensed with. 5. Arguments in favor of plural party system are that it is the very foundation of democracy and performs the function of integrating and coordinating the general will of the people. In particular, party members among the respondents favor the existence of political parties and oppose independent candidates running in the National Assembly election. 6. The most important reason why some of the respondents are against the existence of multiple political parties is that their activities accelerate political corruptions and sacrifice national interests through partisan causes. 7. Whether people support any particular political party or oppose it depend more upon the leading figures of the party than the degree of social representation, policy or accomplishments of that party. The dominant tendency to rely upon personality in selecting public candidates reveals the backward attitude of the Korean people towards political party. 8. On the question of adequate number of political party required, half of the interviewers support the bipartisan system and one-thirds the three-party system. Members of the New Democratic Party are overwhelmingly in favor of the two-party system , while members of minor parties are unanimously in support of multi-party system. 9. Most respondents think that only if a man filed an application he is fully qualified to be a party member and that political party is more concerned with formalities than with the exercise of rights or fulfilment of duties on the part of party members. 10. Many respondents consider it to be legitimate to raise political fund through the party members' contribution or from the sources of national treasury so as to use it as a safeguard against political corruptions and injustices. Those respondents who possess high consciousness as party member emphatically argue in favor of the need of party members' contribution. However, it reflects their view only and it is doubtful whether this argument could be realized. 11 Many respondents, more among party members than among nonparty members, expressed opinions in a negative way about intra-party democratic practices. Though many of them favor in principle the democratic order among political parties, they anticipate that it is hardly feasible because it is completely left to the voluntary ruling in each party's constitution. More party members than non-party members, and more intellectuals than illiterates support the possibility of democratizing intra-party order. 12. Looking into the changes in Korean attitude toward political party in the past and present, one can learn that gradual changes have taken place ranging from complete distrust of it in the immediate aftermath of the Liberation to a relatively general trust in it in the later stage. The present tendency suggests us that there will be a possibility of significant transition into a total trust in the political party system among Korean people in the future. Nonetheless, there is also a tendency for many people to discredit party members and policies, event though there are a few who trust political party. The expectation for political party does not seem to be improved. For the future of party politics, many people bear an opinion that supra-party movement is likely to emerge in order to overcome the bad influence of plutocracy. Yet, many people still expect that party-centered vote and peaceful change of regime shall be eventually made possible despite the inactivity of National Assembly.

직장암 수술 후 국소재발과 예후

김태윤,백무준,김성용,신응진,박내경,이문수,김창호,송옥평 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.1

Locally recurrent rectal cancer is a difficult clinical problem. Local recurrence following treatment for rectal cancer is a major cause of morbidity and mortality. The reported range of local recurrence rates following surgical treatment for rectal cancer has varied from 4% to 50%. We retrospectively reviewed the charts of 142 rectal cancer patients from January 1991 to December 1999. Analysis of patients factors included age, gender, type of surgery, and adjuvant therapy. Tumors were assessed for level, stage, and grade. Local recurrence and distant metastases were also documented. Variables influencing local recurrence in this group were identified and disease-free survival is determined. Of the 142 patients(74 males, 68 females; mean age 62.6 years), 137 consecutive patients operated on for rectal cancer and followed up to December 2000 (range 23-118months) were analyzed. Local recurrence rate was 18.3%. Age and sex of patients, type of surgery, location of tumor in the rectum, size, morphology and grading of the tumor were all unrelated to the event under investigation. At Cox regression, the Dukes stage and the postoperative radiotherapy were the only independent prognostic factors for local recurrence, and Dukes stage (Hazard ratio=2.89, p<0.001) and local recurrence (Hazard ratio=3.31, p<0.01) were the only independent factors associated with improved survival.

급성 충수염으로 내원한 환자에서의 충수 방선균증

임수경,최희정,손효문,최윤이,조민선 이화여자대학교 의과학연구소 2014 EMJ (Ewha medical journal) Vol.37 No.S

방선균증은 그람양성 혐기성 세균인 Actinomyces에 의해 유황 과립을 함유하는 특징적인 종괴나 농양을 형성하는 만성 화농성 및 육아종성 감염으로 경부-안면 감염이 흔하며, 복부-골반 감염, 흉부 감염이 나타날 수 있고, 복부-골반 방선균증은 복부수술, 난관-난소 농양, 자궁 내 삽입장치와 관련이 있다[1]. 방선균증은 미생물학적 배양검사와 조직학적 검사를 통해 진단하지만, 세균의 동정이 어려워 진단은 주로 현미경적 검사를 통하여 유황 과립의 존재에 의존하게 된다. 방선균증 중에서 복부-골반 감염은 이전에도 다수 보고된 바이며, 자궁 내 삽입장치를 가지고 있던 경우 복부 방선균증이 확인된 증례나[2], 장 점막의 약화를 유발할 수 있는 복부 수술 이후 발생한 방선균증의 증례는 보고되었으나[3], 방선균증을 일으킬 수 있는 수술 병력이나 유발요인이 없는 환자에서 일차적으로 충수의 방선균 감염이 발견된 경우는 드물다. 저자는 병력상 장 점막의 약화로 인한 방선균증의 침범을 유발할 수 있는 복부 수술력 없이, 급성 충수염으로 내원한 환자에서 충수절제술 시행 후 진단된 충수 방선균증증례를 4예 경험하여 문헌 고찰과 함께 보고하고자 한다.