철근콘크리트의 균열특성에 따른 철근부식도 실험연구

정영수,이상국 중앙대학교 건설환경연구소 2000 環境科學硏究 Vol.11 No.2

Reinforced concrete is, in general, known as high durability construction material under normal environments due to strong alkalinity of cement. It is, however, well known that moderate or minor cracks in reinforced concrete should be the most serious causes to deteriorate the durability of RC structures. Furthermore, chloride contents penetrating through unexpected cracks in reinforced concrete bridges become to weaken the corrosion resistance of reinforcement steel in concrete and then to accelerate the deterioration of concrete durability. The objective of this experimental research is 1) to evaluate the effect of various corrosion protection systems for reinforced concrete specimens with moderate or minor cracks which are exposed to cyclic wet and dry seawater, and then 2) to develop effective corrosion protection systems for reinforced concrete bridges under the exposure of various detrimental environments such as seawater, deicing and etc.

부식 촉진 실험에 의한 철근방식 연구

정영수,이상국 중앙대학교 건설환경연구소 2001 環境科學硏究 Vol.12 No.2

최근 사회기반시설의 신설 및 확충에 따른 해양 · 해안 콘크리트 구조물의 증가는 열악한 철근부식환경하의 콘크리트 구조물의 내구성에 관한 관심을 고조시키고 있다. 콘크리트 구조물의 철근부식은 하천사 부족에 따른 해사 사용 및 동기철 제설재 사용등으로 인한 염분침투로 가속화되고 있으며 이는 콘크리트 구조물의 내구수명저하를 초래하여 이에 대한 대책이 시급한 실정이다. 본 연구는 신설 및 기존 콘크리트구조물에 대한 철근 방식 대책에 관한 연구로서 전기방식기법인 외부전원법 및 희생양극법을 이용하였고, 신설구조물에서 사용될 수 있는 부식억제제(방청제) 기법을 이용하였다. 희생양극법은 Zinc를 이용한 Zinc-Plate 기법과 구조물에 결함이나 파손이 발생했을 때 피복 콘크리트의 보수 및 철근을 보호하기 위한 Zinc-Mortar기법을 사용하여 철근방식효과를 규명하고자 하였다. 또한, 철근 부식억제 방청제는 국내에서 시판되고있는 3종류의 방청제를 선정하여 본 연구를 수행하였다. 철근부식측정은 Half-cell방법을 이용하였으며 연구결과 전기방식기법, Zinc Plate기법 등의 철근방식효과를 확인할 수 있었다. Recently, construction activities of marine concrete structures have been increased as part of enlargement project of various infrastructures to keep up with the economic growth. Since these strcutures are directly exposed to detrimental steel corrosion environment, such as chloride penetration caused by sea sand due to shortage of river sand and deicing agent in winter, it needs to establish efficient counter-measures to prohibit durability deterioration of concrete structures. The objective of this experimental research is to investigate and develop pertinent corrosion protection method for new and aged concrete structures, such as corrosion inhibitors and impressed current system for new concrete structures, and zinc-mortar and zinc-plate method of sacrificial cathodic protection system for repair and rehbilitation of aged concrete structures. Corrosion measurements are corrosive potential by the half cell method. It was confirmed the effectiveness of cathodic protection method, zinc-plate method from this test.

내분비 기능이 없는 췌장 도세포 종양-1예 보고

정재걸,박건춘,윤상기,한덕종,조영국 울산대학교 의과대학 1993 울산의대학술지 Vol.2 No.1

Nonfunctioning pancreatic endocrine tumor is a rare disease without showing any specific clinical manifestations. Indolent growth of this tumor has a prognosis in between functioning endosrine tumor of pancreas and exocrine adenocarcinoma. We experienced a nonfunctioning pancreatic islet tumor in 59 year old male patient. The tumor in the body of pancreas was clinically silent and had no hormonal activity in immunohistochemical staining

상업스포츠센터 조직 구성원의 직무스트레스와 조직몰입의 관계

정의권,김용국 중앙대학교 스포츠과학연구소 1999 體育硏究 Vol.- No.12

This study was carried out to examine the effect of job stress on the organizational commitment within commercial sports facilites and to recognize their importance. The subjects of study were 182 staff members all of whom worked at commercial sports facilites located in Taegu city as of May, 1999, and who were selected through a cluster sampling method. The measuring tools used were questionnaires for job stress and organizational commitment. The factorial analysis and the reliability test showed a similarity to the preceding study and as a result, the questionnaires proved relatively reliable. Each questionnaire consisted of Likert's 5 step scale. The subjects were told to fill in the questionnaires using a self-administration method. The data that proved to be analyzable were computerized using SPSS WIN/PC + V8.0 in accordance with the study plan. Desciptive-statistical analysis, t-Test, ANOVA and multiple regression analysis were performed for data analysis. The following are the conclusions of the data analysis in accordance with the study plan ; 1. The level of job stress through supervisor and task characteristic factors is high. Personnel have a high level of a sense of mission and responsibility and an average level of a sense of pride. 2. The order the personnel are, the higher the level of job stress through role conflict factors are. Married people have a high level of job stress through supervisor factors. Personnel who are at a high position and receive high salary have a high level of job stress through supervisor factors. Especially, when the career is good, the level of job stress caused by task characteristic factors is also high. 3. Men have higher levels of a sense of mission than women. The higher or longer the age, position and career get, the higher the sense of mission and responsibility are. And staff members who receive a high monthly income have high levels of a sense of responsibility. 4. Among subcategories of job stress, supervisor factors have a positive effect on the sense of mission and responsibility, but role conflict factors have a negative effect on the sense of mission, pride and responsibility. Task characteristic factors have a positive effect on the sense of pride. Social support factors, however, have no effect on organizational commitment.

비침습적 검사를 이용한 수술후 하지 심부 정맥 혈전증의 감시

김영욱,정한준,윤봉호,김신윤,이상국,변경환,김태헌 경북대학교 병원 1997 경북대학교병원의학연구소논문집 Vol.1 No.1

Deep vein thrombosis is recognized as a common complication in surgical patients in western countries especially in patients with high risk factors. The purposes of this study were to detect leg DVTs in early postoperative period by non-invasive surveillance and to analyze the risk factors of DVT. One hundred seventy one patients who underwent major operations(67 curative resection of colorectal cancer, 64 total hip replacement, 38 femur operation for fracture, and 2 colon resections for benign colon disease) were included for the prospective surveillance of leg DVT within 2 weeks after the operations. For the surveillance of leg DVT, strain gauge plethysmography(SPG) and Duplex scanning of both legs were completed for all patients except 10 patients. These 10 patients were examined in only one leg. The patients with past history of leg DVT or under prophylactic anticoagulant therapy were excluded from this study. To determine the risk factors related with leg DVT formation, age and sex of the patients, indication of surgery or surgical procedures, duration of operation, position during the operation, duration of postoperative immobilization, and preoperative serum level of antithrombin III (AT- III) were analyzed using Chi-square test. After performing SPG of 342 legs, 38 legs, showed abnormal on venous outflow/venous capacitance discriminant line chart, and 13 legs of 12 patients showed the finding(s) suggesting DVT on duplex scanning. Among the patients with abnormal duplex findings, 7 limbs(53.8%) were symptomatic, but the remaining 6 legs were silent. In 6 (15.8%) patients of 36 femur operations, 3(4.7%) of 64 total hip replacements and 3(4.5%) of 67 curative resections of colorectal cancer developed DVT by duplex scanning in the iliac(5), femoral-popliteal(6), and isolated calf(2) veins. After analyzing the risk factors, we could not find any statistically significant(p<0.05) factor related with leg DVT.

Pspice를 이용한 RL 회로 해석

오재근,박영국,박찬성,정영호 內務部 國立科學搜査硏究所 2001 國立 科學 搜査 硏究所 年報 Vol.33 No.-

검도 머리치기 유형에 따른 상지의 근전도 비교 분석

장언량,박영훈,염창홍,서국웅,이경순,강영택,양충모 釜山大學校 附設 體育科學硏究所 2004 體育科學硏究所 論文集 Vol.20 No.-

Of the fencing club members at D university in B city, the four skilled members and the 4 unskilled members were selected. The MVC of the left brachioradialis, right brachioradialis and left flexor carpi radialis, right flexor carpi radialis each was measured in each group according to the striking directions as they act 'striking left right head'......

습기제거시스템의 성능에 관한 연구

유성연,정민호,홍정표,심국진,김광영 忠南大學校 産業技術硏究所 1997 산업기술연구논문집 Vol.12 No.2

The performance of moisture removal system is investigated analytically and experimentally. The program for the moist air calculation and for the condensing tube design are developed to examine the factors which affect moisture removal rate. Experimental apparatus comprises condensing tube, cooling system, vacuum pump, measurement and control devices. Thermoelectric cooling system and vapor compression refrigeration system are used to cool the air, and the performance of two systems are compared each other. Thermoelectric cooling system is compact and free from noise and vibration, but cooling rate of it is relatively slow compared to that of vapor compression refrigeration system. Air velocity, indoor temperature and humidity, temperature of coolant, size and material of condensing tube are found to affect the performance of moisture removal.

HPGe 검출기에 의한 지각방사선의 핵분광학적 연구

전재식,채하석,진응국,이철영,조혁,하정우 충남대학교 기초과학연구소 1992 연구논문집 Vol.12 No.-

고순도 Ge(HPGe) 검출장치를 사용한 현장측정을 통하여 지각방사선에 대한 핵분광학적 연구를 수행하였는바 지각방사선장의 핵분광학적 특성차이를 규명하기 위하여 지면의 자연방사성 핵종분포가 대표적 전형인 충남대학교 캠퍼스내 미경작 개활지 잔디밭과, 우라늄 함량이 높은 곳으로 알려진 괴산군 덕평리 지역 등 특이한 두 지역을 측정지점으로 선택하였다. 환산선량의 비교확인을 위하여 HPGe 분광측정은 3″ø×3″원통형 NaI(T1) 섬광검출기에 의한 분광측정과 동시에 수행하였으며 본 연구에 사용된 HPGe 검출기에 대한 스펙트럼-선량율 환산인자 G(E)는 감마선속이 검출기 축에 수직 입사하는 것으로 가정하고 Monte Carlo 방법으로 씨뮬레이션한 감응스펙트럼들을 사용하여 산출하였다. 이 G(E)를 사용하여 산출된 선량율(D˙_Ge)은, 이미 기준기급 전리함과의 비교 교정을 통하여 스펙트럼-선량 환산체계가 확립된 바 있는 NaI(T1) 검출기로 구한 선량율(D˙_NaI)과 만족스러운 일치를 보였으며 D˙_Ge와 D˙_NaI 사이의 상관계수는 +0.9988, 회귀 방정식의 기울기는 1.001을 나타내었다. 측정한 스펙트럼에서는 미미한 크기의 ^137Cs 감마선 피크가 확인되었으나 1960년대에 수행되었던 대기권 핵실험의 영향이나 Chernobyl 원전사고의 영향은 관측되지 않았다. Study of terrestrial gamma-rays was carried out by means of in-situ spectrometry using high purity germanium (HPGe) detector system. Two distinguishable fields of measurements, namely, uncultivated flat lawns in CNU campus where the distribution of natural radionuclides in the ground in known to be quite typical and well-known uranium rich area of Dukpyung-ri in Gwoesan-kun were selected in order to specify the difference in spectrometric characteristics of the fields. In-situ HPGe spectromety was accompanied by scintillation spectrometry with 3″ø×3″cylindrical NaI(T1) detector for comparative confirmation of derived dose rates from the spectra measured. Spectrum-dose rate conversion operator, G(E), of our particular HPGe detector was calculated using response spectra simulated by Monte Carlo method with an assumption of gamma-ray beams incident vertically to the detector axis. Resultant dose rates (D˙_Ge) showed satisfactory agreement with those obtained by NaI(T1) spectrometry and corresponding G(E) operation (D˙_NaI) of which system has been well-established through intercalibration with a reference ion chamber. Correlation coefficient and the slope of regression equation between D˙_Ge and D˙_NaI came out to be +0.9988 and 1.001, respectively. Though traceable height of ^137Cs gamma-ray peak was identified on the field spectrum, ground contamination of fission products released from atmospheric nuclear test performed in 1960s and possibly from Chernobyl accident was not observed as of today.

일개대학병원에서 수막알균 백신 사용의 경험

손동욱,이찬우,정영국,조래정,이혜경,김은실,이진수,정문현 대한감염학회 2007 감염과 화학요법 Vol.39 No.6

Meningococcal infection is a life threatening disease that leaves serious sequelae in spite of appropriate treatment, thus vaccination for high risk groups are Important for the prevention of meningococcal diseases. However, the vaccine for Neisseria meningitidis has not been available in Korea until we introduced bivalent (serogroup A and C) polysaccharide vaccine for the first time for relief works in our university hospital. The vaccine was administered from January 2005 to March 2007 to 317 persons. of the groups administered, the largest group among them were 133 (133/317, 42%) students who planned to study abroad and needed the vaccination for secure entrance to school dormitories. This group was followed by health care workers, travellers to the regions of the world with high risks of meningococcal diseases, and splenectomised patients. To ratioalize the domestic use of meningococcal vaccine, the availability of vaccines first needs to be simplified by introducing them to the domestic market; for this to be possible, the approval system for vaccines should be reformed and epidemiogical studies need to be carried out.