하중스펙트럼을 이용한 강철도교의 피로해석에 관한 연구

변근주,오진우,김영진 연세대학교 산업기술연구소 1986 논문집 Vol.18 No.1

The objective of this study is to propose the effective stress ranges on steel railroad bridges using the load spectra for actual trains, and to develope a method for prediction of remaining life. The traffic on railroad from Suwon to Cheonan is modeled using 19 cases of loading and probability density curves of stress ranges are derived. Although the three-parameter Erlang curve provide a slightly closer fit, the two-parameter Rayleigh curve is selected for use in this study because it is simpler and provides an adequate fit. Finally. the effective stress ranges are computed using the Rayleigh distribution. These results can be used in predicting the remaining life of steel railroad bridge with S-N curves.

디지탈 주파수 체배기 구성에 관하여

李根泳,崔訓淳 成均館大學校 科學技術硏究所 1984 論文集 Vol.35 No.1

Frequency multipliers find applications in the Fourier and Walsh spectrum measurments of periodic signals. Earlier digital frequency multipliers use two counters;l) An up counter which determines the period of the input signals by the number of clock pulses accumlated in a period of signal. 2) A down counter preset to the contents of up counter when zero. In this process the considerable amount of errors is introduced in output frequency because the fractional counter contents are ignored in the frequency multiplication phase. This paper uses two clock signals CLK_1, CLK_2 which drive I count-er and F counter respectively at proper time instant to reduce error. The considerable amount of errors are reduced by using method.

경골 과부 골절에 대한 관절경하 탐색자를 이용한 정복방법

문영래,김근호 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Purposes : To evaluate the result and technique of arthroscopic reduction with probe for Intraarticular fracture of the tibial condyles. Materials and Methods : From October 1998 through January 2000, 15 patients were treated for Intraarticular tibial condylar fracture. Average follow up were 22 months, with a range of 13 to 46 months According to Schatzker classification,3 cases were classified as pure cleavage(type Ⅰ),8 cases of cleavage with depression(type Ⅱ) and 4 cases of pure central depression(type Ⅲ) For accurate reduction, we used probe to elevate the depressed fracture fragment. Results : The results were obtained from 15 patients who had been Intraarticular tibial condylar fracture and Judged by Porter's criteria Eleven cases revealed more than good results. Conclusion : Intraarticular reduction method for tibial condyle fractures had several advantage such as providing accurate reduction, preventing cartilage perforation and easy to perform.

역유동층 반응기와 삼상유동층 반응기를 이용한 유기물 제거에 관한 연구

박영식,안갑환,추석열,서근학,송승구 부산대학교 1995 生産技術硏究所論文集 Vol.48 No.-

구형의 섬유상 플라스틱을 media로 사용하여 3상 유동층 생물막 반응기와 역유동층 생물막 반응기로 유기물 제거효율을 비교 실험하였다. 유입수의 SCOD가 1800㎎/L였을 때 역유동층 생물막 반응기와 3상 유동층 생물막 반응기의 제거효율은 각각 94%, 92.5%였다. 유기물 부하율이 2㎏COD/㎥.day였을 때 역유동층 생물막 반응기의 미생물 농도는 2810㎎/L, 3상 유동층 생물막 반응기의 경우는 2300㎎/L 였다. 반응기 부피, 공기유량, media 형태 및 폐수성상이 모두 같은 조건에서는 두 반응기 모두 유기물 제거효율과 미생물 농도 등에서 거의 비슷한 거동을 나타내었다. A number of experiments were conducted to examine the COD removal efficency and the biomass concentration of the three phase fluidized bed biofilm reactor(TFR) and inverse fluidized bed biofilm reactor(IFR) using fibrous plastic ball and synthetic wastewater. When the influent SCOD was 1800㎎/L, SCOD removal efficiency of IFR and TFR were 94% and 92.5%, respectively. When organic loading rate was 2㎏COD/㎥.day, the biomass concentrations of the IFR and the TFR were 2810㎎/L and 2300㎎/L, respectively. When operated at the same conditions on reactor volume, air flow rate, media type and wastewater characteristic, two reactors showed a very similar performance.

위성망에서 효율적인 순방향 에러정정 기법

박태근,김영환,박재현,박현민,최병석 明知大學校 産業技術硏究所 1999 産業技術硏究所論文集 Vol.18 No.-

In this paper, a new method of FEC(Forward Error Correction) using multi-stage Viterbi coder is proposed, with effectively reduce BER in satellite ATM Networks. In terms of structural complexity, proposed multi-stage Viterbi coder simpler than the traditional single-stage coder based on the same BER performances. And, through simulation, proposed coder shows excellent error correction capabilities compared with traditional FEC schemes. Also, we propose a selective FEC mechanism that adaptively changes the number of stages to satisfy the QoS(Quality of Service) requirements. This Selective scheme can be easily implemented using the PLCP(Physical Layer Convergence Protocol) frame structure.

六味地黃湯이 生理活性指標와 淋巴球細胞數에 미치는 影響

金榮權,柳逢夏,朴東源,柳基遠 대한한방종양학회 1998 대한한방종양학회지 Vol.4 No.1

Yookmijihwangtang has been widely used oriental herb prescriptions, which is healing some discuss that come from insufficiency of innate essence and deficiency of kidey Ki. the meaning of healing discusses tonification of insufficient innate essence and insufficient kidney Ki can be regarded as reinforcement of wholely power of keeping homeostasis, that is correlated with immuno-responsibility which protects subject from outer antigen to keep normal vital condition. This study was aimed to investigate correlative effects of Yookmijihw angtang water abstract on the RBC, WBC, blood CD4+ Theler cell count, blood testosterone, blood cAMP and blood cortisol. 40 Sprague-Dawley male rats were divided into 5 groups(Normal, Control, SampleⅠ, SampleⅡ, SampleⅢ), 6 animals in every group. Normal group was not treated anything, control group was administrated normal saline in the same desage of sample Ⅰ. 3 Sample groups were received some of Yookmijihwangrang water abstract at one time per 24 hours during 5 days in different dosage. Sample Ⅰ (1/3 10pack/ml), SampleⅡ (1/62pack/ml), SampleⅢ(1/2.4pack/ml). After finishing treatment, all experimental svbjects were killed for blood sample on RBC, WBC, blood CD4+ T helper cell count, spleen CD4+ T helper cell count, axillary lymph node CD4+ T helper cell count. .blood cAMP, blood testosterone and blood cortisol. The results were as follows: RBC and WBC were incrased in all sample groups. Blood CD4+ Thelper cell count(CD4+ T cell count in the blood/whole lymphocyte count in the blood ×100%) was Mormal 46.17±5.88. Control 44.50±4.37, Sample Ⅰ 53.00±2.28. Sample Ⅱ 53.83±3.87, SampleⅢ 52.17±2.93. By the 95% Duncan ANOVA all experimental groups(sampleⅠ, sampleⅡ, sampleⅢ) showed slight significant difference from Nornal and Control. Blood cAMP(nmd/l) were Normal 1.12±0.17, Control 1.16±0.32, SampleⅠ 0.46±0.07, SampleⅡ 0.44±0.04, SampleⅢ 0.54±0.04 All cxperimental groups were signigicantly different from both Normal and Control groups(p<0.05). Blood cortisol(m l/ml) were Normal 100.00±2.00, Control 90.00±4.00, Samplc Ⅰ 440.00±5.00, SampleⅡ 520.00±40.00, SampleⅢ 470 00±7.00, Blood cortisol of all experimental groups were signifieantly increased(p<0.05). The results suggest that Yookmijihwangiang water abstract could be administrated to patienrts who have some diseases insufficient essence.

수학적 사고력 신장을 위한 산수과 학습의 기초와 기본에 관한 고찰

손용규,신현권 晋州敎育大學校 初等敎育硏究所 1993 初等敎育硏究 Vol.3 No.-

하중스펙트럼을 이용한 고속도로 판형교의 피로해석에 관한 연구

최홍식,변근주,이기성,김영진 연세대학교 산업기술연구소 1987 논문집 Vol.19 No.1

The objective of this study is to propose effective stress ranges for a fatigue analysis and to develop a method estimating the fatigue life of existing plate girder bridge. The procedure for the effective stress range is consisted of three parts. In the first one, the external loading conditions are systematized by analyzing the actual traffic volumn from Taejeon to Taegu on the Seoul-Pusan Expressway. In the seconed one, the load spectrums for each loading case are elicited. Finally, the stress spectrums are derived from the dynamic analysis of the bridges. The single effective stress range is obtained using Rayleigh probability density function. The effective stress ranges obtained may give a realistic estimate of the life of existing bridges. The results of this study may provide the basic data for the fatigue test.

고등학교 복싱선수의 지구성 훈련이 혈당, 혈청지질 및 지단백의 변화에 미치는 영향

이윤관,이영웅,권판근,이한우 창원대학교 체육과학연구소 2002 경남 체육연구 Vol.7 No.2

트레이닝에 따른 인체의 반응 및 적응성 변화 양상은 운동의 강도, 빈도, 형태 및 기간에 따라서 달라지며, 피검자의 단련수준에 따라서도 달라진다. 이러한 변화 요인 중에서 혈청지질(Serum Lipid) 지단백(Lipoprotein)의 수준 변화는 심장계 질환 및 관상동맥 질환의 예방과 치료에 있어서 의학계는 물론 스포츠 과학분야에 있어서도 매우 많은 관심을 갖고 있으며, 이에 대한 연구가 활발하게 진행되고 있다. 유산소적 운동은 혈청지질 및 지단백, 그리고 혈당에 미치는 영향이 크다는 견해이지만 실제 연습방법에 따른 이러한 변화의 특성에 관한 보고는 거의 없는 실정이다. 따라서 본 연구자는 질병 예방과 운동선수의 훈련 효과를 높이기 위해 복싱선수들을 대상으로 하여 연습방법을 달리한 지구성 훈련을 시켜 혈청지질 및 지단백 그리고 혈당의 변화를 비교, 분석하여 운동선수들의 연습방법에 도움을 줄 수 있는 자료를 제공하고자 한다. 집중적 연습과 분산적 연습에 따른 유산소 지구성 운동을 13주 4일간 실시한 후 혈당, 혈청지질 및 지단백의 변화에 미치는 영향을 알아보기 위해 복싱선수 15명을 대상으로 Total-Cholesterol, HDL-Cholesterol, Triglyceride, Total-protein 및 glucose를 측정하여 비교 분석한 결과 다음과 같은 결론을 얻었다. 1.Total-Cholesterol은 훈련전 보다 13주 4일간 훈련후 모든 집단에서 증가하였으며, 집단간에 유의한(p<.05) 차이를 나타내었다. 2.HDL-Cholesterol은 훈련전 보다 13주 4일간 훈련후 집중적 연습집단에서는 증가하였으며, 집단간 유의한(p<.05)차이를 나타내었다. 3.Triglyceride는 훈련전보다 13주 4일간 훈련후 모든 집단에서 감소하였으며, 집단간 매우 유의한(p<.001) 차이를 나타내었다. 4.Total-Protein은 훈련전 보다 13주 4일간 훈련후 모든 집단에서 증가하였으며, 집단간 매우 유의한(p<.001) 차이를 나타내었다. 5.Glucose는 훈련전보다 13주 4일간 훈련후 모든 집단에서 감소하였으며, 집단간 유의한(p<.05) 차이를 나타내었다.

스퍼터링 조건에 따른 Co 박막의 증착속도 및 미세구조의 변화

백주열,박창만,최영근,이기암,황도근 단국대학교 신소재기술연구소 1992 신소재 Vol.2 No.-

DC 마그네트론 스퍼터링법으로 제조된 코발트 박막에 대해 증착속도 및 미세구조에 미치는 스퍼터링조건의 영향을 조사하였다. 증착속도는 투입전력이 커질수록 증가하였으며, 아르곤 압력이 커질수록 감소하였는데, 이는 투입전력의 증가로 인한 타게트 표면의 이온전류 밀도의 상승과 Ar 압력증가에 따른 비산효과의 증대로 인한 타게트 표면의 이온 전류 밀도의 감소로 고찰되었다. 투입전력이 커질수록 결정립의 크기가 감소하였으며, 투입 전력에 관계없이 특정한 면이 발달하지 않는 비정실 구조를 나타내었다. Ar 압력에 관계없이 비정질 구조를 나타내었다. We have investigated the influence of sputtering condition on deposition rate and microstructure of Co thin film produced by the method of DC Magnetron Sputtering. Deposition rate increased with the input power due to the rise in ionic current density on the surface of target, and decreased with the pressure of Ar gas due to the decrement of ionic current density by the effect of diffusion. Microstructure of the Co thin film became a finer structure with the increase in the input power, and showed amorphous irrespective of the charge of the input power and the pressure of Ar gas.