미소 진폭 파형벽을 가진 유로내에서 응축이 수반되는 초음속유동의 Prandtl-Meyer 팽창에 관한 실험적 연구

권순범,안형준,김병지,선우은 경북대학교 산업기술연구소 1993 産業技術硏究誌 Vol.21 No.-

The characteristics of the Prandtl-Meyer expansion of supersonic flow with condensation through a channel with a small amplitude wavy wall are investigated experimentally. In the present study, for the case of moist air flow in the type of indraft supersonic wind tunnel, the dependency of formation and reflection locations of the oblique shock wave and the distribution of flow properties are clarified by flow visualization and pressure measurement with the variation of the specific humidity and temperature at the entrance of the wavy wall and the attack angle of the wavy wall to the main stream. Also, we confirm that the wavy wall plays an important key role in the formatio of oblique shock wave, and that the effect of condensation on the flow field appears apparently.

뇌종양 수술 후 방사선치료에 의해 발생한 이차성 조증

유범희,우종민,신형진,김승태 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.5

국소적 대뇌 병변에 의한 이차성 조증은 드물게 보고되어 왔다. 저자들은 정신과적 병력이 없던 사람이 좌측 측두엽 뇌종양의 종양 절제술을 받은 뒤 별다른 문제없이 잘 지내다가 수술 후 방사선치료를 받은지 약 4개월만에 조증 삽화를 보인 증례를 경험하였다. 정위적 조직검사 결과 이는 방사선치료에 의한 후유증으로 지연성 손상이 일어나 우측 해마 부위가 괴사되었기 때문이 것으로 밝혀졌다. 본 증례를 통해 저자들은 이차성 조증의 발병과 우측 해마 부위의 병변이 밀접하게 관련되어 있음을 확인할 수 있었다. 이처럼 이차성 조증과 뇌의 국소적 병변 부위 사이의 관련성을 밝히는 것은 앞으로 일차성 조증의 신경해부학적, 신경생물학적 원인을 규명하는 데에도 크게 기여할 수 있으리라 생각된다. Secondary mania associated with focal brain lesion has only rarely been reported. The authors report a case of secondary mania after postoperative radiation therapy for primary brain tumor. Localized necrotic lesion was found in the right basotemporal lobe involving hippocampus, which might be the result of late delayed damage of the postoperative radiation therapy. This case suggests that secondary mania is closely related to focal, right basotemporal lesions. Knowing the relationship between the location of brain lesions and manic syndrome may be helpful to us in understanding the neuroanatomical and neurobiological mechanism of primary mania.

다항 베이즈 요인에 의한 회귀계수 검정에 관한 연구

함형범 서경대학교 1995 論文集 Vol.23 No.2

We present a Bayesian method for pairwise comparisons of hypotheses in a multiple regression with partition on the parameter space of a regression coefficient. The method is derived by introducing partial and multiple Bayes factors for the regression coefficient having a uniform conditional prior. To show the performance of the method, a comparison has been done with other Bayes tests in terms of their respective powers. The comparison via a simulation study indicates that the suggested test enables us to deal simultaneously, without loss of power and any constraints of symmetry about prior distribution, with any number of alternative hypotheses.

확률화응답기법에서의 층화최적배분

함형범 서경대학교 1994 論文集 Vol.22 No.2

다관절 로봇의 경로계획에 관한연구

전형주,정회범,심재홍 순천대학교 공업기술연구소 1990 工業技術硏究所論文集 Vol.4 No.-

In this study, the methods of the trajectory planning which satisfy the given constraints in the control systems, have the minimum segment­transition time, and reduce the deviation from straight­line path were investigated. The study was carried out in the joint space on the transition motion between two points and on the several segment motion along multiple points. The kinematic model of Rhino XR­2 robot was adopted in the simulation for the trajectory planning.

Lidocaine에 의한 경련이 뇌조직에서 c-fos 발현에 미치는 영향

조성범,채한정,강장숙,김형룡 원광대학교 생체재료·매식연구소 1998 원광생체재료·매식 Vol.7 No.1

Recently, a variety of stimuli including convulsion, ischemia and noxious stimuli have been shown to induce the expression of c-fos mRNA in central nervous system (CNS). In this study, c-fos expression in both mRNA and protein (Fos) levels is examined up to 72 hr in brain regions, including hippocampus, piriform cortex, neostriatum, amygdala, dentate gyrus, cerebral cortex, and thalamus during lidocaine-inducced convulsion. Intraperitoneal administration of lidocaine (120 mg/kg) induces generalized convulsion of rats within 10 min and subsequent increase of c-fos expression in both mRNA and Fos protein levels in dentate gyrus, piriform cortex, amygdala, neostriatum, cerebral cortex, hippocampus, and thalamus. A prominent induction of c-fos mRNA and Fos protein in dentate gyrus suggests that dentate gyrus plays an important role in the process of lidocaine-induced convulsion. These results suggest that c-fos may participate in plastic changes of central nervous system associated with stimuli such as seizure activity.

IAEA HTR-10 Benchmark Problem-I에 대한 RELAP5 평가계산

김형석,정범진 제주대학교 공과대학 첨단기술연구소 2004 尖端技術硏究所論文集 Vol.15 No.1

An IAEA Benchmark problem for HTR-10 was assessed in order to evaluate the capability of RELAP5 code, which is a system thermal-hydraulic safety analysis code for water reactors. Assessment results were compared with the results of THERMIX code, a thermal-hydraulic analysis code for HTGR (High Temperature Gas Cooled Reactor). The calculated results showed good agreement with those obtained by the THERMIX code with a maximum deviation of around 4.5%. This deviation was estimated to originate from the simplification of complicated geometry and from the modeling capability of heat transfer characteristics in the HTGR components such as the water cooler and the air cooler. Especially, it was found that the radiation heat transfer in the reactor cavity played an important role in the after heat removal by the RCCS. Thus, it is concluded that it is necessary to evaluate and improve relevant models both for the convection and radiation heat transfer in order to enhance the code analysis capability to the HTGR.

충남대학교 교내 산림환경 개선을 위한 경관 가치 평가

송형섭,박범진,권기원 忠南大學校 環境問題硏究所 1997 環境硏究 Vol.15 No.-

The purpose of this study is to obtain some useful informations for improving the campus forest landscape of Chungnam National University. Based on two kinds of surveyed data relating campus forest landscape resources and the respondents visual preference ratings, geographical features and physical characteristics of forest landscape are investigated. Twenty-four photos were taken for visual preference survey. With a total 100 respondents, relative scenic beauty of each forest scenes could be explained in terms of influence factors of physical characteristics. Three variables in model could be accounted for 65% of total variables in perceived forest scenic beauty. Results indicated that campus forest landscape must be improved greatly in the scenic views and so on. To improve current situation, some alternatives including improvement scheme and cost have to be proposed newly.

종자 입자를 이용한 SiO_(2) 단분산 입자 제조에 관한 연구

이민형,이범석,김우식 慶熙大學校 材料科學技術硏究所 1999 材料科學技術硏究論集 Vol.12 No.-

In this study, to control secondary particles of silica, SiO_(2) seed growth experiments have been carried out variable concentrations of tetraethylorthosilicate(TEOS), agitation speed, feeding time, concentration of [NH_(3)], [H_(2)O]. The formation of secondary particles was reduced with increasing feeding time(t_(F)), agitation speed. Increasing TEOS concentration promote formation of the secondary particles. Increasing NH_(3) concentration reduce formation of the secondary particles.

Temporal and Spatial Variation of Chlorophyll a Concentration in Lake Soyang

김범철·심재형·조규송 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

폭이 좁고 길며 수심이 깊은 나뭇가지형 인공호인 소양호에서 하류로 부터 상류에 이르기까지 10개 정점에서 클로로필 농도의 계절적 변화와 수평적 변이를 조사하였다. 하루에서는 계절적으로 식물플랑크톤의 최대 번성기가 일정치 않아 불규칙한 시간적 변화를 보였으먀, 대체로 늦은 봄부터 초가을 까지 가장 높은 클로로필 농도를 보였다. 그러나 지류하천이 유입되는 수역에서는 매년 늦은 가을에 주기적으로 연중 최고의 클로로필 농도를 보였다. 조사 정점간의 수평적 변이를 보면 크로로필 농도는 지류 하천의 유입부에서 가장 높게 나타났으며 하류쪽으로 갈수록 농도가 낮아지는 경향을 보였다. 하류댐 앞에서의 농도는 5μg/l 이하로 빈영양호 수준인데 반하여 지류의 유입부에서는 때로는 100μg/l를 넘는 부영향호 이상의 농도를 보여 주었다. 상류 수역에서 식물플랑크톤 밀도가 높은 현상은 유입 하천의 영양염류 농도가 호수보다 높다는 것으로 입부 설명될 수 있으나, 극심한 대량번식을 유발할 정도로 높지는 않은 것으로 보아, 식물플랑크톤을 유입부에 밀집시키는 또 다른 지작이 존재하는 것으로 생각되며, 이는 지류 하천의 중층으로의 유입과 소양호에서 겨울과 초뭄을 제외하고는 항상 우점종으로 나타나는 쌍편모조류의 주광성에 기인하는 것으로 보인다. Seasonal and horizontal variations of chlorogphyll a concentration were surveyed in Lake Soyang, a long, narrow and deep artificial lake in a mountainous sistrict. Pattern of seasonal variation at the dam site did not show regular blooms, but irregular blooms occurred through late spring to early autumn, and at the stream inlet sites a yearly regular bloom could be observed in late autumn. Chlorophyll a concentration varied greatly with the distance from the inflowing stream inlet. Though the concentration was in the range of oligotrophic level (5μg/l) at the dam site, peak value at the inlet sites far exceeded eutrophic level (up to more than 100μg/l). Such high density of phytoplankton in the upstream area can be partly explained by the high phosphate concentration in the inflowing stream water. In addition phytoplankonm aggregation may be attributed to a physical process which could trap dinoflagellates coupled with their phototactic moveattributed to a physical process whic could trap dinoflagellates coupled with their phototactic movement. These dinoflagelates are dominant species in the research lake throughout the warm season.