암석 슬러지를 이용한 건자재 개발

이필호,이구연,전철수,연규석,이윤수,인교진 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

본 연구는 1993년부터 춘천시 신동면 형돌리 산 62번지 내에서 흑운모 화강암 및 편마암 암석을 원자재로 사용하여 건설기초재료인 쇄설골재 및 인공모래를 생산하는 업체로부터 제품 생산 후 발생하는 토양 스러치 케익이 연간 약 10만 입방정도 발생한다는 사실에 기초하여 석산에서 채취된 페잔토(석분)의 화학적, 물리적, 역학적 특성을 조사하여 석분의 이용 가능성을 확인하기 위한 실험으로 단위 시멘트량을 400kg, 잔골재율을 45% 그리고 물-시멘트비를 65%로 고정하고 잔골재 중 석분을ㄹ 0%, 10%, 20%, 30%, 40%, 50% 및 60%로 치환하여 제조된 콘크리트의 기초적 성질을ㄹ 시험하였다. 그 결과 석분의 치환율이 높을 수록 공기량은 증가하고 슬럼프값이 감소하였는데 이는 미세한 입자인 석분을 잔골재의 일부로 치환함으로써 비표면적이 증가하였기 때문인 것으로 사료된다. 압축강도와 휨강도는 모두 석분의 치환율이 증가할수록 압축강도와 휨강도는 다소 감소하는 경향을 나타냈으나 큰 성능차이는 보이지 않는 다는 것을 알 수 있었다. 이상의 실험을 통해 석분을 시멘트 콘크리트에 사용했을 경우 약간의 성능저하는 있지만 잔골재로의 활용이 가능하다는 것을 알 수 있었다. 그러므로 앞으로 건조수축, 균열, 크리이프 특성 및 내구성에 과한 연구가 더욱 심도있게 이루어져야 폐자원인 석분의 이용이 가능하리라 판단된다. This study aims to make cement concrete using crushed stone fines which are produced at Chuncheon city, Hyuldongri and find it's applications. According to the experimental results, when ratio of crushed stone fines was increased, air contents were increased and slump values were decreased. Also, the compressive strength and flexural strength were decreased when ration of crushed stone fines was increased. Although these strengths are decreased, the crushed stone fines can be used to construction materials because the decreased amounts are not so much.

A Study on the Odor Management of Traditional Markets in the Old and New Towns

Yeon-Kyo KOO,Ji-Min YOUN,Jae-Yeon JO,권우택 한국웰빙융합학회 2022 웰빙융합연구 Vol.5 No.4

Purpose: Odor generated in traditional markets causes discomfort, hindering the pleasant life of residents, and complaints of odors are steadily increasing every year. Odor is defined as a smell that stimulates a person's sense of smell by stimulating hydrogen sulfide, mercaptans, amines, and other irritating gaseous substances. Research design, data and methodology: It is not easy to grasp and manage the current status of the odor analysis of living odors such as traditional markets. Seongnam City has an advanced new town of Bundang and Pangyo, while old cities such as Sujeong-gu are relatively underdeveloped. Results: As a result, the gap between the old city center and the new city center widens, so it is urgent to develop a balanced development. Based on this, the market of Seongnam-si is divided into the old city center and the new city center, and the odor complaint in the traditional market is analyzed to find a solution. A survey was conducted to understand the current status of odor management in the Seongnam-si market and the odor felt by users. Moran Market, Seongnam Jungang Market, and Kumho Market and Dolphin Market, located in the new city center, were selected as targets. The items of the survey consisted of the frequency and cause of the odor, the current status of market management, matters that need improvement, and efforts to resolve the odor. Conclusions: Therefore, this study aims to help citizens feel better about odor environment in places where odor standards are exceeded or complaints occur frequently, and to help local governments and market merchants establish more efficient and useful development plans.

Effect of severe neonatal morbidities on long term outcome in extremely low birthweight infants

Koo, Kyo-Yeon,Kim, Jeong-Eun,Lee, Soon-Min,NamGung, Ran,Park, Min-Soo,Park, Kook-In,Lee, Chul The Korean Pediatric Society 2010 Clinical and Experimental Pediatrics (CEP) Vol.53 No.6

Purpose: To assess the validity of individual and combined prognostic effects of severe bronchopulmonary dysplasia (BPD), brain injury, retinopathy of prematurity (ROP), and parenteral nutrition associated cholestasis(PNAC). Methods: We retrospectively analyzed the medical records of 80 extremely low birthweight (ELBW) infants admitted to the neonatal intensive care unit (NICU) of the Severance Children's Hospital, and who survived to a postmenstrual age of 36 weeks. We analyzed the relationship between 4 neonatal morbidities (severe BPD, severe brain injury, severe ROP, and severe PNAC) and poor outcome. Poor outcome indicated death after a postmenstrual age of 36 weeks or survival with neurosensory impairment (cerebral palsy, delayed development, hearing loss, or blindness) between 18 and 24 months of corrected age. Results: Each neonatal morbidity correlated with poor outcome on univariate analysis. Multiple logistic regression analysis revealed that the odds ratios (OR) were 4.9 (95% confidence interval [CI], 1.0-22.6; $P$=0.044) for severe BPD, 13.2 (3.0-57.3; $P$<.001) for severe brain injury, 5.3 (1.6-18.1; $P$=0.007) for severe ROP, and 3.4 (0.5-22.7; $P$=0.215) for severe PNAC. Severe BPD, brain injury, and ROP were significantly correlated with poor outcome, but not severe PNAC. By increasing the morbidity count, the rate of poor outcome was significantly increased (OR 5.2; 95% CI, 2.2-11.9; $P$<.001). In infants free of the above-mentioned morbidities, the rate of poor outcome was 9%, while the corresponding rates in infants with 1, 2, and more than 3 neonatal morbidities were 46%, 69%, and 100%, respectively. Conclusion: In ELBW infants 3 common neonatal mornidifies, severe BPD, brain injury and ROP, strongly predicts the risk of poor outcome.

RPA 시스템 서비스의 사용의도에 관한 연구

구교연(Kyo Yeon Koo),차상훈(Sang Hoon Cha),최정일(Jeongil Choi) 한국IT서비스학회 2021 한국IT서비스학회지 Vol.20 No.4

In the rapidly developing 4th industrial revolution. RPA is increasing in use at home and abroad due to its advantages of simplifying workflow and providing flexibility and scalability at the same time. Thus, this paper conducted an empirical study on companies using RPA to determine which factors affect the intention to use the services provided by RPA systems. As system characteristics, exogenous variables were selected as information quality, system quality, and service quality of the information system success model. The endogenous variables were selected as the system acceptance factors for the performance and effort expectancy of the integrated technology acceptance model, and the perceived economic values and functional values were additionally selected. For the purpose of this study, a structured questionnaire was used for empirical analysis and the proposed hypothesis was verified through the path analysis of structural equations. As a result of the study, there was no significant relationship between service quality and effort expectancy, between service quality and economic value, and it was verified that the relationship between other factors was positively significant.

용량결합형 전극에서 가이드링에 의한 전기장 제어

구교욱(Kyo-Woog Koo),이연(Yeon-Lee),구경완(Kyung-Wan Koo) 대한전기학회 2019 전기학회논문지 Vol.68 No.11

In the case of display PECVD, VHF is introduced as the driving frequency. In addition, since the electrode shape has a large area rectangular structure, nonuniformity caused by the standing wave effect and skin effect occurs. In this case, even small changes in the process variables affect the nonuniformity. Against this we propose the electric field control method using guide ring as a part of reduction effect and fine tuning. Using the guide ring, the electrical influence and the optimization method were confirmed by the response surface Methodology and Taguchi experiment. It is considered that fine tuning is possible by utilizing the electrical properties of each factor.

Intrathoracic Desmoid Tumor Presenting as Multiple Lung Nodules 13 Years after Previous Resection of Abdominal Wall Desmoid Tumor

Koo, Gun woo,Chung, Sung Jun,Kwak, Joo Hee,Oh, Chang Kyo,Park, Dong Won,Kwak, Hyeon Jung,Moon, Ji-Yong,Kim, Sang-Heon,Sohn, Jang Won,Yoon, Ho Joo,Shin, Dong Ho,Park, Sung Soo,Oh, Young-Ha,Pyo, Ju Yeon The Korean Academy of Tuberculosis and Respiratory 2015 Tuberculosis and Respiratory Diseases Vol.78 No.3

Desmoid tumors are rare soft tissue tumors considered to have locally infiltrative features without distant metastasis until now. Although they are most commonly intraabdominal, very few cases have extra-abdominal locations. The origin of intrathoracic desmoid tumors is predominantly the chest wall with occasional involvement of pleura. True intrathoracic primary desmoid tumors with no involvement of the chest wall or pleura are extremely rare. We recently experienced a case of true intrathoracic desmoid tumor presenting as multiple lung nodules at 13 years after resection of a previous intraabdominal desmoid tumor.

변전소 소음예측 프로그램 개발

具敎善(Kyo-Sun Koo),權東震(Dong-Jin Kweon),禹貞旭(Jung-Wook Woo),郭周植(Joo-Sik Kwak),姜鍊旭(Yeon-Woog Kang) 대한전기학회 2007 전기학회논문지 Vol.56 No.9

Energized power transformers in substations make unwelcome noises which propagate to nearby residential areas. As the excessive noise level become a target of public grievance than ever, utilities are seeking solutions to it. This paper introduce a power transformer noise prediction program which can give utilities effective solutions. Once a noise source is given, the program calculates the propagated noise level at certain points. The estimated result is rendered as noise contour map. To validate the accuracy of the program, the predicted noises are compared to measured one in real substations and proven to be acceptable within a margin of 5 percent.

연부조직육종의 수술후 방사선 치료결과

김연실(Yeon Shil Kim),장홍석(Hong Seok Jang),윤세철(Sei Chul Yoon),유미령(Mi Ryeong Ryu),강기문(Ki Moon Kang),정수미(Su Mi Chung),김훈교(Hoon Kyo Kim),강용구(Yong Koo Kang) 대한방사선종양학회 1998 Radiation Oncology Journal Vol.16 No.4

목 적 : 최근들어 연부 조직 육종의 치료방법이 광범위 구획절제에서 사지기능을 보존하는 제한적 수술과 방사선/항암화학요법의 다병용치료로 변환되고 있으며 광범위 수술과 유사한 치료성적을 거두고 있다. 저자들은 수술후 방사선 치료를 시행한 연부 조직 육종 환자를 대상으로 치료 결과 및 실패 양상을 알아보고 관련된 예후 인자를 분석하여 수술 후 방사선치료의 역할을 알아보고자 하였다. 대상 및 방법 : 대상환자는 1983년부터 1994년까지 치료한 60명이었고 모두 추적관찰이 가능했으며 평균 추적기간은 50개월이었다. 원발병소는 상·하지가 35례(58%)로 가장 많았고 체간 12례(20%), 두경부 7례(12%)였으며 병리학적 유형에 따른 구분은 악성섬유구종 14례(23%),지방육종이 10례(17%), 악성신경섬유종 7례(12%) 등 이었다. 전체환자중 6례를 제외하고는 조직학적등급의 분석이 가능했고 grade I, II, III가 각각 27례(45%), 3례(5%), 24례(40%)였다. 수술적 절제는 19례(32%)에서 광범위절제, 36례(60%)에서 변연절제, 5례(8%)에서 국소절제를 시행하였다. 방사선치료선량은 28.8- 80Gy였고 25례에서 방사선치료와 함께 항암화학 요법을 병용하였다. 결 과 : 최종분석 시 실패 양상은 국소재발이 20례(25%), 원격전이 7례(12%), 국소재발과 원격전이를 동반한 경우가 14례(23%)였다. 원격전이한 환자는 구제치료와 상관 없이 모두 사망하였고 국소재발한 환자중 5명이 구제치료에 성공하여 무병생존하였다. 전체환자의 2년 및 5년 국소제어률은 68.0%와 48.7%로 비교적 저조한 결과를 보였다. 국소제어율에 영향을 미친 예후인자는 조직학적 유형, AJCC 병기, 조직학적 등급, 수술의 범위, 수술절연 침범 유무 및 잔존종양 정도, 림프절 전이 유무(p <0.05)였다. 전체 환자의 5년 생존률과 5년 무병생존률은 각각 60.4%, 36.6%였고 평균 생존기간은 89개월이었다. 단변량 분석에 의한 생존률에 영향을 미친 예후인자로는 조직학적 유형, AJCC 병기, 림프절 전이 유무, 조직학적 등급, 수술절연 침범 유무와 잔존 종양 정도 였다. 결 론 : 결론적으로 본 연구 결과 연부 조직 육종에서 제한적 수술과 수술 후 방사선치료로 비록 저조한 국소제어률을 보였으나 사지 절단 혹은 광범위 구획절제와 비교시 유사한 생존률을 얻었다. Purpose : The major goal of the therapy in the soft tissue sarcoma is to control both local and distant tumor. However, the technique of obtaining local control has changed significantly over the past few decades from more aggressive surgery to combined therapy including conservative surgery and radiation and/or chemotherapy. We retrospectively analyzed the treatment results of the postoperative radiation therapy of soft tissue sarcoma and its prognostic factor. Materials and Methods : Between March 1983 and June 1994, 60 patients with soft tissue sarcoma were treated with surgery and postoperative radiation therapy at Kang-Nam St. Mary's hospital. Complete follow up was possible for all patints with median follow up duration 50 months (range 6 - 162 months). There were 28 male and 32 female patients. Their age ranged from 6 to 83 with a median of 44 years. Extremity (58%) was the most frequent site of occurrence followed by trunk (20%) and head and neck (12%). Histologically malignant fibrous histiocytoma (23%), liposarcoma (17%), malignant schwannoma (12%) constitute 52% of the patients. Daily radiation therapy designed to treat all areas at a risk for tumor spread upto dose of 4500-5000 cGy. A shrinking field technique was then used and total 55-65 Gy was delivered to tumor bed. Twenty-five patients (42%) received chemotherapy with various regimen in the postoperative period. Results : Total 4 1 patients failed either with local recurrence or with distant metastasis. There were 29 patients(48%) of local recurrence. Four patients (7%) developed simultaneous local recurrence and distant metastasis and 8 patients (13%) developed only distant metastasis. Local recurrence rate was rather higher than of other reported series. This study included patients of gross residual, recurrent cases after previous operation, trunk and head and neck prima ry. This feature is like ly explanation for the decreased loca l control rate . Five of 29 patients who fa iled only loca lly were salvaged by re- excis ion and/or re- irradiation and rema ined free of disease . Factors affecting loca l control include histologic type , grade, stage , extent of operation and surgica l ma rgin involvement, lymph node metastas is (p <0.05). All 21 patients who fa iled distantly are dead with progress ive disease at the time of this report. Our overall survival results are similar to those of larger series . Actuarial 5 year overall survival and disease fresurvival were 60.4 %, 36.6% respectively. Grade, stage (being close association with grade), residual disease (negative ma rgin, microscopic, gross) were significant as a predictor of survival in our series (p <0.05). Conclusion : Combined surgery and postoperative radiation therapy obtained 5 year survival rate comparable to that of radical surgery.

소프트웨어 결함 정보를 이용한 샘플링 기법의 비교

구교진(Kyo Jin Koo),김태연(Tae Yeon Kim),채흥석(Heung-Seok Chae) 한국정보과학회 2013 한국정보과학회 학술발표논문집 Vol.2013 No.11

변압기 온라인 예방진단 센서의 점검현황

구교선(Kyo-Sun Koo),권동진(Dong-Jin Kweon),진상범(Sang-Bum Chin),곽주식(Joo-Sik Kwak),강연욱(Yeon-Woog Kang) 한국조명·전기설비학회 2005 한국조명·전기설비학회 학술대회논문집 Vol.2005 No.5월

Preventive diagnostic system for power transformer prevents the sudden power failure through monitoring of abnormal symptoms. KEPCO has a(Opted the preventive diagnostic system at nine 345kV substations since 1997. Application techniques of the diagnostic sensors were settled, but diagnostic algorithm and practical use of accumulated data are not yet established. To build up the diagnostic algorithm and effective use of the preventive diagnostic system, the reliability of the data accumulated in a server computer is very important. Therefore, this paper describes problem when apply system to substation and solution way to improve reliability of the system.