心彈圖에 관한 臨床的 硏究 : 第2編. 本態性 高血壓症의 心彈圖 PART Ⅱ. BALLISTOCARDIOGRAM IN ESSENTIAL HYPERTENSION

吳相鎭,金萬在,朴熙明 대한의학협회 1964 대한의학협회지 Vol.7 No.12

유한요소법과 경계요소법을 이용한 광도파로 내에서의 산란특성 해석

吳炅姬,朴宰弘 東亞大學校 大學院 1995 大學院論文集 Vol.20 No.-

Scattering from arbitrary discontinuities in an optical wave guide can be analyzed by combining finite element method and the modal expansion technique. By introducing the boundary element method far the semi-infinite region, however, the number of nodal points can be reduceded considerably. In this paper, a numerical algorithm is developed, which utilizes FEM, BEM and the modal expansion method. The algorithm can be applied to arbitrary discontinuty problems. The validity of the algorithm is tested for the well-known step-discontinuity problem.

經緯系의 收縮에 關한 硏究

金熙山,李在坤 忠南大學校 1962 論文集 Vol.2 No.-

In general, the contraction of thread in a fabric can be determined by the following factors such as tension, ends or picks per inch, weaves, counts and turns per inch. In order to simplify the calculation we ignored the effects of tension and twists on contraction, and classified the fabric as follows: a) a square fabric b) a fabric whose angle of curvature of warp or weft proceeds the other. c) a fabric whose angle of curvature of warp or weft slightly differes from the other. Firstly, we determined the maximum possible density of warp or weft as follows: D=1/cosθ(de+df) where θ; angle of curvature de; dia. of warp df; dia. of weft D; maximum possible density of warp and weft. The results are as follows L = {I×C×(de+df)×n/D}×D/N where L; original length of warp or weft in a unit length of fabric. I; number of curvature in a repeat due to weaves. C; constant of angle of curvature. n; number of threads that continuously float in a repeat due to weave. And on the variation of tension during weaving we analysed the variation of tension due to three principal motion of loom and classified the nature of variation as follows; such as a) tension which varies continuously during weaving b) tension which varies intermittenly during weaving And summerized as follows; A) tension which varies according to shedding and beating motion varies intermittenly B) tension which added to the warpbeam increases by the decrease of warp beam dia. C) tension which varies according to letting off and taking up motion varies intermittently or continuously by the mechanism.

沃化水銀 單結晶의 成長과 그 物理的 特性에 關한 硏究

田載植,張忠根,吳熙弼 충남대학교 기초과학연구소 1984 연구논문집 Vol.5 No.-

Investigation on the physical properties of mercuric iodide single crystals grown by both means of liquid and vapour growth was performed. In addition to the measurement of band gap energy and hardness of the crystals grown, studies on the relations between nucleation, supersaturation and transport rate as a function of source temperature in the process of vapour growth as well as solvent evaporation rate, crystal density and crystal size as a function of growing time in liquid growth were also carried out. As a result of the analysis, it is shown that the total number of crystallites, Ns, in vapour growth is given by In N_s = -4.47 × 10 exp (-2)G + 0.012T were G=1/ln^2 (1+r) and r is supersaturation, and T is source temperature in K, whereas the mass transport rate, J, is expressed by J = -0.96 × 10 exp (3)T^-1 + 2.52. In liquid growth, the solvent evaporation rate was found to be the most important factor that affects the pattern of the crystal grown. Density and band gap energy measured were, on average, 6.3g/㎤ and 2.1 eV, respectively.

沃化水銀 (Hgl_2)半導體 放射線檢出器 製作에 關한 硏究

田載植,張忠根,吳熙弼 충남대학교 기초과학연구소 1983 연구논문집 Vol.4 No.-

As a preliminary study of fabricating semiconductor gamma-ray detector for practical use at room temperature, α-phase HgI_2 single crystals were grown by means of statical evaporation after appropriate purification of commercially available chemical grade HgI_2 powder. For the crystals grown, examination or measurements of such physical properties as thermal resistivity, photoconductivity and band gap energy including an evaluation of spectrometric characteristics, were carried out. The band gap energy were found to be 2.11eV. Results are summarized and illustrated in graphical forms. Throughout the study it is concluded that a priori purification of HgI_2 condition of crystal growing, polishing the surface and ohmic contact in fabricating a detector are particularly important parameters on which quality of the detector is largely dependent.

二重 Norch 先端에서 塑性變形拳動에 관한 硏究

鄭世喜,林載奎,金貴子 全北大學校 1986 論文集 Vol.28 No.-

The fracture toughness of elasto-plastic materials was directly affected by the size, shape of plastic zone which are great important parameter in large scale fracture mechanics. This paper is to observe the influences of the interference of notches on plastic deformation at notch tip of double notch. Specimens were tested by four point bending, and then the shape of the plastic deformation could be visualized with the technique of recrystallization. Beside, numerical method for the analysis of the plastic zone with a F.E.M. (Finite Element Method) were used. The obtained results are summarized as follows: 1) The behavior of plastic zone on double notch was different from single notch. 2) When the plastic zone was saturated at a limitation on the middle between the notches, the behavior of the plastic deformation of double notched specimen was similar to that of the single notch. 3) Maximum equivalent plastic strain was shown at the tips of both single and double notch. 4) The evaluated model of plastic zone by F.E.M. corresponded to the results of the experiment.

鋼 熔着金屬의 熱變形脆化에 關한 硏究

鄭世喜,金台永,林載奎,鄭熙敦,朴昌彦 全北大學校 1984 論文集 Vol.26 No.-

The susceptibility of weld metal(AWS, F76-EH14) on hot straining embrittlement has been examined. The sharp notch was machined on the weld metal of 1st bead and on coarse-grained HAZ transformed by next pass. After machining the notch, these specimens were bended at 250℃ to receive the hot straining embrittlement and they were done COD fracture toughness test by the three point bending, and then the change of plastic zone at notch tip was evaluated by microhardness test. The obtained results are summarized as follows. 1. Fracture toughness of weld metal was greater than that of base metal. 2. Fracture toughness of the coarse-grained HAZ was similar to that of weld metal. 3. Hardness of weld metal reheated by next pass was lower than that of weld metal owing to the effect of heat treatment. 4. Plastic deformation of the coarse-grained HAZ was less than that of weld metal.

자연방사선량중 ^222 Rn 기여성분 정량해석

전재식,오희필,채하식,이병영,김도성 충남대학교 기초과학연구소 1989 연구논문집 Vol.9 No.-

옥외 라돈이 호흡기관에 주는 선량을 측정·평가할 목적으로 CR-39 비적검출기를 내장한 라돈 컵을 사용하여 대기중 라돈농도를 측정하였다. 직접형 검출기 및 개방 컵과 필터 컵의 구조를 갖는 CR-39 비적검출기에 대한 라돈검출인자는 공기중의 농도가 잘 알려진 표준라돈 조사시설에서 이들 검출기와 라돈컵을 일정기간 조사하여 결정하였다. CR-39를 70℃, 30% NaOH용액으로 220분간 화학부식하였을 때 직접형 검출기와 개방 컵, 필터 컵에 대한 라돈검출인자는 각각 0.273, 0.0813, 0.0371 tr㎜^-2/(37Bqm^-3·d)였다. 또한 1988년 5월에서 1989년 3월까지 대전(충남대학교)에서 측정한 대기중의 라돈농도는 개방 컵에 의한 결과는 2.74-18.87Bq/㎥(0.07-0.5pCi/ℓ)로서 연평균 8.25Bq/㎥(0.22pCi/ℓ)이었으며, 필터 컵에 의한 결과는 1.67-19.76Bq/㎥(0.05-0.54pCi/ℓ)로 연평균 8.18q/㎥(0.22pCi/ℓ)이었다. 그리고 대기중의 라돈농도에서 ^(220)Rn의 기여성분은 무시할 수 있을 정도인 것으로 판단되었다. 측정한 옥외 대기중의 라돈농도와 부위별 폐선량모형으로부터 ICRP 표준인의 호흡기관에 대한 유효선량당량률은 약 60nSv/h(0.5mSv/y)로 평가되었다. A study for the assesssment of dose given by outdoor radon to respiratory system has been carried out by making use of radon-cups containing CR-39 plastic track detectors. Detection efficiencies were determined by irradiation of the radon-cups in a standard radon chamber of known concentration. Thus determined detection factors of CR-39 plastic track detedtor in bare, open cup and filtered cup geometry are found to be 0.273, 0.0813 and 0.0371tr㎜^-2/(37Bqm^-3·d) respectively, which are chemically etched in 70℃, 30% NaOH for 220 minutes. The outdoor radon concentrations measured at Taejeon(Chungnam National University) from May 1988 to March 1989 are in the range of 2.74-18.8Bq/㎥(0.07-0.51pCi/l) by open cup and 1.67-19.76Bq/㎥(0.05-0.54pCi/l.) by filtered cup. The annual averaged value of the measured outdoor radon concentration is 8.2Bq/㎥(0.22pCi/l). Corresponding effective dose equivalent rate to respiratory system of ICRP standard man is assessed to be 60nSv/h or 0.5mSv/y.

食道 및 氣道異物의 統計的 考察

柳恒熙,姜炳吉,秋淵秀,朴載勳,金春吉,朱良子 대한이비인후과학회 1976 대한이비인후과학회지 두경부외과학 Vol.19 No.4

방사선 측정 및 해석 연구 : 원자로 냉각수중의 방사능해석에 의한 결함핵연료봉의 평가 Assessment of Defected Fuel by Analysis of Reactor Coolant Activities

양재춘,오희필,전재식,이호연,오헌진,정문규,박해용 충남대학교 기초과학연구소 1987 연구논문집 Vol.7 No.-

중성자와 우라늄의 핵반응에 의해 생성된 핵분열생성물의 물리적 특성을 이용하여 원자로 내의 핵연료 상태를 해석하는 모델을 개선하였다. 이 모델에서는 고체 핵연료 내에서 특정핵종의 핵분열생성물의 생성과 이것이 원자로 냉각재까지 방출되는 과정을 계산하고 추적하여 방사능농도와 결함 핵연료봉의 수를 관계짓는 방정식의 계수들을 결정한다. 핵분열생성물의 거동은 이탈(knock out)과 이동(migration) 두 부분으로 나누어 해석하였으며 트램프 우라늄의 영향을 분리할 수 있도록 하였다. 실측자료로는 가압 경수형 원자로인 고리 원자력발전소 1호기의 1차 냉각재를 분석해서 얻은 I-131과 I-133의 방사능 강도를 이용하였다. 이 실험자료와 위 방정식에서 구한 방사능 강도로부터 구한 결함 핵연료의 수는 제3주기에서 9.34±1.13개 제6주기에서 0.294±0.092개로 나타났다. An improved mothod of assessing fuel status by analyzsis of the fission product in the reactor coolant system is proposed. The release mechanism of specific fission products is established for determination of the coefficients in the equations which relate the radioactivities with the amount of detected fuel. Knock-out and migration models are employed in the formulation of the release mechanism. The influence of the tramp uranium is quantified. Sample calculations were made for KNU 1 reactor system using the I-131 and I-133 concentrations in the primary coolant. The estimated number of defected fuel pins in the third and sixth cycles appeared to be 9.34±1.13 and 0.294±0.092, respectively.