河川水質의 推計學的 變動性에 關한 硏究

白景元,宋在偶 弘益大學校 科學技術硏究所 1994 科學技術硏究論文集 Vol.5 No.-

The stochastic structures of water quality time series were examined. These time series include daily observations in streamflow, water temperature, BOD, and dissolved oxygen deficit. Autoregressive integrated moving average(ARIMA) models were used to describe the random components of these time series. It was found that except for the BOD the Arima models provide very satisfactory results.

디자인 실기영역의 학습 평가에 관한 연구

백경원 동의공업대학 2001 論文集 Vol.27 No.1

An evaluation of design may play an important role in development an index of education value. The purpose of practical education is to get an achievement. Thus, it is very important for appraiser to observe practical courses and analysis during processing of design works. However, Practical evaluations have been conducted negligently, which are too ease and subjective to apply originally the purpose of education. Therefore, this present study suggests objective and reasonable evaluation methods, which are expected to high efficiency to apply into practical fields of education.

충북 남부지역 중소 제조기업의 경쟁력 제고를 위한 경영 및 애로기술 실태조사 연구

윤상원,구경완,정성진,백기영,김선훈,서용성,이근복 호서대학교 반도체제조장비국산화연구센터 2001 반도체장비학술심포지움 Vol.2001 No.-

본 연구에서는 충북 남부 3개군 지역(옥천 · 보은 · 영동)의 중소 제조기업의 경영실태 및 애로기술을 대상으로 실증조사 되었다.·지역의 특정상황의 전제하에 지방 중소기업들의 실질적인 문제점들을 발견하고, 그 개선 방안을 탐색함은 물론 산 · 학 · 연 컨소시엄 사업의 성공적인 수행을 위해 시도되었다.세부적으로는 중소 제조기업의 경영 및 애로기술 특성을 일반적 사항, 경영애로요인, 경영전략, 현장개선기법, 정보화, 제품 및 공정 기술상의 애로기술 현황파악의 6개 영역으로 조사되었다. 조사결과들은 추후 산 · 학 · 연 공동기술개발 사업에 있어 창의적, 틈새적 과제발굴 및 신제품 기술개발의 토대마련이 될 뿐 아니라, 지역경제 발전을 위한 산 · 학 관의 지원 전략 수립에 적극 활용 될 것으로 판단된다.

8.3% Carbamide Peroxide 함유 펜 형 자가미백제인 BIancTis Forte의 색조개선 및 안전성에 관한 임상연구

이진경,민선홍,홍성태,오소람,정신혜,황영혜,유성엽,배광식,백승호,이우철,손원준,금기연 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.2

This clinical study evaluated the whitening effect and safety of polymer based-pen type BlancTis Forte(NIBEC) containing 8.3% carbamide peroxide. Twenty volunteers used the BlancTis Forte whitening agent for 2 hours twice a day for 4 weeks As a control. Whitening Effect Pen (LG) containing 3% hydrogen peroxide was used by 20 volunteers using the same protocol. The change in shade (ΔE^(*) color difference) was measured using Shadepilot™ (DeguDent) before, during and after bleaching (2 weeks, 4 weeks and postbleaching 4 weeks). A clinical examination for any side effects (tooth hypersensitivity or soft tissue complications) was also performed at each check-up. The following results were obtained. 1 Both the experimental and control groups displayed a noticeable change in shade (ΔE) of over 2 No significant differences were found between the two group (p>0.05) implying that the two agents have a similar whitening effect. 2 The whitening effect was mainly due to changes in a and b values rather than in L value (brightness). The experimental group showed a significantly higher change in b value thus yellow shade than the control(p < 0.05) 3 None of the participants complained of tooth hypersensitivity or soft tissue complications confirming the safety of both whitening agents 8.3%의 carbamide peroxide를 함유한 펜형 코팅용 미백제인 BlancTis Forte (NIBEC, Seosul & JinCheon)를 실험군으로, 3% hydrogen peroxide를 함유한글 Whitening Effect Pen (LG. Seoul) 제재를 대조군으로 각각 피험자 20명에게 2시간씩 1일 2회 제조사의 지시대로 치아표면에 4주간 적용하도록 지시하고 색조개선 효능과 안전성을 평가하였다. 미백 효과는 미백 전 및 미백 2주, 4주 및 미백 종료 4주 후에 Shadopilot™을 이용하여 색 변화를 측정하였고, 매 내원시기마다 모든 환자는 치수생활력 검사와 치주 및 치태 검사를 통해 부작용 여부 (치아과민증 및 구감 내 연조직의 부작용)를 기록한 후 다음과 같은 결과를 얻었다. 1.실험군 및 대조군의 색 변화량 (ΔE)은 2이상으로 인지할 수 있는 색 변화를 보였으며, 두 제품 간에는 통계적으로 유의한 차이를 보이지 않아 (p > 0.05) 유사한 미백효능을 나타냄을 알 수 있었다. 2,미백효과는 명도의 개선보다는 주로 a. b값의 변화에 의한 것으로 특히 실험군에서 b값의 변화, 즉 황색조의 개선효과가 대조군에 비해 유의성 있게 높은 것으로 나타났다 (p <0.05). 3.치아나 치은의 과민증이나 이상증상을 호소하는 피험자는 없어 두 제품 모두 안전성을 확인할 수 있었다.

저 발열량 페유 소각기 개발에 관한 실험적 연구

전영남,백원석,송형운,유경석,김성천 조선대학교 환경공해연구소 2004 環境公害硏究 Vol.18 No.-

The advanced waste oil incinerator is suggested that has heat recirculation region in the combustor to burn out the waste oil completely in high temperature zone and heat recuperator in the left side of combustion cavity which plays a role of the flame stabilization of main burner flame by heat recovery of exhaust gas to incinerate waste oil contained water. In order to investigate a simultaneously incineration efficiency of the vessel waste oil contained the hazardous waste which occurs from the vessel and the sea outflow waste oil experiments have been carried out using the emulsion fuel mixed the water and bunker fuel oil C and the blend mixed the light oil and the waste surrogate material (acetonitrile:CH_(3)CN). The results of experiments showed that the waste oil incinerator developed in this study was excellent for the incineration efficiency of waste oil at an air ratio of 1.46 and DRE (destruction and removal efficiencies) of CH_(3)CN was 99.9996% ("5 nines"). And optimum operating conditions for the secondary air flow rate of internal mix burner, preheating temperature and injection point of shipboard waste oil contained acetonitrile were suggested.

유량변동에 따른 소양강유역 수질의 통계학적 해석

최한규,백경원,최용묵,최진우 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.B

This research was conducted with the aim of efficiently managing large scale of rivers such like Songyang-river through predicting water quality change with analyzing the characteristics of the flowing in nutrients and pollutants. The main result will be used as basic data for effectively operating reservoirs through controling water quality and quantity. The relationship between quantity of flow and water quality was analyzed and pollution loading into the basin was estimated. Three areas of Soyang-river upstream and one area of Suip-cheon in Yanggu-gun were selected as research sites. Flow and water quality were measured simultaneously. The relation between quantity of discharge and pollution concentration and between quantity of discharge and pollution loading were analyzed by statistical method, respectively. We provided a rating curve through measuring quantity of discharge(collection quantity of discharge)and pollutograph and pollution loading curve through water quality data. Also, we analyzed the correlation between quantity of discharge per unit area and pollution loading per unit area in each basin. As resurt of this research, Buk-cheon spot revealed an excellent first grade water quality for the items including BOD5, DO, and SS. The correlation coefficient between Buk-cheon spot's quantity of discharge and pollution loading was 0.896~0.996, showing the validity of analysis applying correlation curve formula of quantity of discharge and pollution loading in the same spot. Also, pollution loading per unit area of the items including BOD5, COD, DO, SS, T-N, T-P increased as area of basins get increased following the sequence of Buk-cheon, Suip-cheon, Naelin-cheon spots.

推計學的 模型에 의한 河川流量의 模擬發生

宋在偶,白景元 弘益大學校 1986 弘大論叢 Vol.18 No.2

The purpose of synthetic generation of river flows based on the stochastic theory is to make possible a better design of water resources systems by generation of long term data which have the same statistical characteristics of historical discharge data. This study included the generation of monthly and annual discharges by Thomas- Fiering model and Monte Carlo model, the comparative study with the historical data and genreated data, and the change of monthly generated discharges into annual discharges. Discharges at Yeoju were characterized by log-normal distribution, and the annual discharges were identified as a time series of persistence absent. The statistical characteristics of the historical data were maintained in the generated data, but the small differences between historical and generated data were produced by the errors in the random number generation. And fit distribution type of the annual discharges could be seen from the annual discharges obtained from the generated monthly discharges.

농구 선수의 만성 슬개건염

서경호,서경묵,김성원,김백곤,송인섭 大韓再活醫學會 1998 Annals of Rehabilitation Medicine Vol.22 No.6

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

반측안면소체증의 측두골 전산화 단층촬영소견

한종규,한경렬,백병준,김형환,배원경,김일영 순천향의학연구소 2005 Journal of Soonchunhyang Medical Science Vol.11 No.1

Hemifacial microsomia(HFM) is a craniofacial disorder and complex malformation syndrome with a variable and asymmetric malformation involving first and second pharyngeal arch derivatives. Multiple etiological mechanisms for HFM have been considered. Mechanisms proposed include genetic factors, early embryogenesis insults involving abnormal neural crest development and migration, and stapedial artery hematoma. HFM is the second most common craniofacial malformation but has been rarely reported in korea, and we report five cases of HFM in temporal bone CT findings. The temporal bone CT findings of five patients aged 6 days and 19 years(mean, 9 years) with hemifacial microsomia were reviewed and evaluated. Particular attention was focused on auricular malformation, external auditory canal, volume of middle ear cavity, ossicular anomaly, facial nerve anomaly and inner ear anomaly. In all patients, temporal bone CT scans revealed the stenosis or atresia of external auditory canals, decreased middle ear cavities, matoid underdevelopment and ossicular anomalies including ossicular ankylosis, but only one patient showed facial nerve or inner ear anomaly. In conclusion, temporal bone CT scan is a useful diagnosis modality of hemifacial microsomia, which is especially more useful in preoperative evaulation and estimation of postoperative prognosis that demonstate middle and inner ear anomalies.