經濟危機의 歷史的 比較 : 韓國經濟에의 示唆 Implications for Korean Economy

朴濟勳 서울大學校經濟硏究所 1998 經濟論集 Vol.37 No.2

우리나라를 비롯한 아시아 경제위기가 이들 경제의 구조조정을 촉진시켜 경제체질개선을 위한 호기가 되어 재도약의 발판으로 작용할지 또는 세계대공학의 전조가 될런지는 여러 요인의 작용에 따라 달라질 것이다. 그러나 그 중 가장 중요한 현실적 변수는 미국경제의 앞날이다. 미국경제에 대한 평가는 미국내에서는 아직은 낙관론이 우세한 것으로 보인다. 그러나 유럽 등에서는 비관론도 적지 않다. 사회주의권의 붕괴의 교훈은 자본주의시장경제체제의 무오류성을 증명하는 것은 아니라고 할 때 비관론에도 대비해야 한다. 그러나 극단적 비관론은 무대책을 낳을 수 있다. 미국경제의 최근의 경쟁력 회복은 80년대 이후 꾸준히 추진해 온 구조조정 노력이 결실을 맺고 있는 것으로 해석해야 한다는 주장도 일리가 있다. 한 가지 확실한 것은 미증유의 경제위기를 겪고 있는 우리로서는 여러 이론ㆍ사상에 입각한 다양한 시각과 견해에 귀기울이면서 모든 경우에 대비하는 냉정한 현실인식 하에 세계의 역사적 경험과 우리의 현실ㆍ조건을 고려한 새로운 발전패러다임의 정립 노력을 서둘러야 할 때라는 사실이다.

급성기 주요우울장애 환자에서 Natural Killer T 세포

박이진,이제훈,이권행,한상익,전양환 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.3

Objectives : To evaluate an association between depression and altered immunity, we examined peripheral T lymphocyte or natural killer (NK) cell measures plasma ACTH and cortisol using the flow cytometry in acute and unmedicated patients with major depressive disorder (MDD). Methods : Forty-two patients with MDD from the outpatient clinic and forty normal controls from the hospital staff were recruited. We applied Hamilton Rating Scale for Depression (HAM-D) and Hamilton Rating Scale for Anxiety (HAM-A) for depressed subjects. Peripheral T lymphocyte or NK cell measures (CD3, CD4, CD8, or CD56) and plasma hormones (ACTH and cortisol) were obtained from all subjects. Results : There were no statistical differences in CD3, CD4, CD8, or CD56 between the two subjects. The number of CD56 cells negatively correlated with HAM-D scores (r= -0.42, P<0.01), but did not correlate with HAM-A scores in patients with MDD. The number of CD56 cells showed strong negative correlation with CD4/CD8 (r= -0.47, P<0.01) in the control group, but not in the depressed group. Patients with MDD had higher cortisol level than controls within the normal range. Conclusion : The trait of immunological imbalance and HPA axis abnormality were shown in patients with MDD. Especially, the severity of depression, but not the anxiety, could be reflected as decreased number of CD56 (NK T) cells in acute and Unmedicated state.

운동전략이 기립자세의 기능적 전방 팔뻗기에 미치는 영향

박제상,권오윤,최흥식,김택훈 한국전문물리치료학회 2000 한국전문물리치료학회지 Vol.7 No.1

The purpose of this study is to determine whether movement strategies affect functional forward reach distance in a standing position. Forty-seven healthy subjects were selected for this study: 23 men and 24 women, with an average age of 22.3. Functional forward reach distances were measured as hip strategy and squat strategy(included knee and ankle movement strategy) in a standing position, respectively. The mean values of functional forward reach distance in hip strategy, squat strategy were 33.57㎝, 29.48㎝, respectively. There was significantly difference in functional forward reach distance between hip strategy and squat strategy(p<.001). There was no difference of functional forward reach distance between male and female in hip strategy, but there was significant difference in other strategy(p<.05). These results suggest that movement strategies should be considered during functional forward reach test in standing. Further study is required to determine whether movement strategies affect functional reach distance in elderly and disabled groups.

정상 성인에서 갈근(Radix puerariae)의 장기투여가 혈중 알콜 농도에 미치는 영향

박제민,김지훈,김명정,김성곤,정영인 大韓神經精神醫學會 1996 신경정신의학 Vol.35 No.6

알콜 의존에서 알콜 소비량을 감소시키고 음주 재발을 방지하는데 효과가 있다는 약물들이 몇 가지 있으며 갈근이 알콜 의존증의 치료에 효과가 있다는 자료들이 있다. 저자들은 정상 성인을 대상으로 알콜을 섭취하게 한 후 갈근 투여 전, 후의 혈중 알콜 농도를 비교함으로써 갈근이 알콜 대사를 방해하여 혈중 알콜 농도를 상승시키는지를 검증하고자 하였다. 알콜을 비롯한 약물 남용이나 의존증이 있거나 기타 정신 질환이 없고 주요 신체질환이 없는 20∼29세 남자 의과 대학생들을 대상으로 하였다. 대상자는 모두 25% 알콜을 3ml/kg(100%알콜 0.75ml/kg)을 마시게 한 후 투여 전, 투여 후 10, 30, 60, 90, 그리고 120분에 혈중 알콜 농도를 측정하게 한 다음 14일간 갈근 하루 6g을 투여한 후 첫날과 같은 방법으로 알콜을 복용하게 한 후 알콜 혈중 농도를 측정하여 약물 투여 전, 후의 알콜 혈중 농도를 비교한 결과 갈근 투여 후에 음주시 30, 60, 90, 그리고 120분에 혈중 알콜 농도가 유의하게 상승하였다. In alcohol dependence, some drugs reduce alcohol consumption and prevent the recurrence of alcohol drinking. There were some evidences that Radix puerariae was effective in the treatment of alcohol dependence. We studied the effect of Radix puerariae on blood alcohol concentration in healthy adults. The subjects were medical students, who did not have major physical disorders, drug abuse or dependence including alcohol, and other psychiatric disorders. After drinking 25% alcohol 3ml/kg, all subjects were measured for blood alcohol concentration at 0, 10, 20, 30, 45, 60, 120 minutes by Alco-sensor Ⅳ. Next day, all subjects were made to take Radix puerariae 6g/day(3g bid) for 14 days. And then blood alcohol concentration were measured by the same method. The results were significant increase in blood alcohol concentration at 30, 60, 90 and 120 minutes.

Dissolved Air Flotation(DAF) 접촉조의 수리동력학적 조건이 입자의 제거에 미치는 영향

유제선,김성훈,신은허,박희경 대한상하수도학회 2003 상하수도학회지 Vol.17 No.1

Hydrodynamic conditions for optimum solids capture within the contact zone, which are governed by the geometry and flow, are not yet well understood. In this research, dimensionless parameters which represent hydrodynamic conditions in the contact zone were derived, using the Buckingham π theorem. Those parameters are Reynolds No. (Re), Froude No. (Fr), Weber No. (We), Local Weber No., and Bubble Capacity No. (Bc). The particle removal rate was investigated by changing each value of the dimensionless parameters. The experimental results indicate that particle removal rate, when gravity dominates and the flow is semi-turbulent (Fr < 0.3, Re < 8000), is higher than when inertia dominates and flow is turbulent. For the We, higher removal rates were obtained in the range of the We < 40. Relative to the Local We, smaller bubbles which are influenced more by surface tension than inertia, demonstrated a higher particle removal rate than larger bubbles. For the Bc, the optimal range is from 0.3 to 0.5. We suggest that these dimensionless parameters can be used to diagnose the performance of and to design a DAF reactor.

인조 합성 테니스 바닥재의 지면 반력 분석

조승제,정미라,서국웅,박승범,윤양진,이훈식,강영택 釜山大學校 附設 體育科學硏究所 1998 體育科學硏究所 論文集 Vol.14 No.-

Some authors suggest that certain types of surfaces are the origin of such injuries. A few years after the first medical concerns about surfaces were voiced, publications of biomechanical measurements apperared, describing accleration, force, and impact measurement on different types of surfaces. In many sport activities, surfaces can be under very high dynamic load. This was the reason for the development of various methods for impact simulation, like the development of various methods for impact simulation, like the artificial athlete. Furthermore, it is important to collect information about the hardness of new and already existing surfaces in sport arenas. The idea on which this measuring system is based Is as follows: The stiffness of the material can be computed from the kinematics measurd at touch down of a rigid body onto a material sample. The results show the following The result for the artifical surfaces(Synpave ace) is surprising. It is known that these surfaces are much harder than synpave rebound classic, synpave spring. This finding suggests that it may be possible that the subjective impression is used as one criterion in the selection of landing(or style) strategies. The number of subjects in this experiment is too small to make statistically significant conclusions. It is shown analytically that when an object a deformable surface, the acceleration it experiences is inversely propotional to its mass. In future, it need to stress that the interaction between shoe and surface is important, and this aspect has now become well accepted. Considering biomechanical aspect in player's injury, it request Korean Standards for synthetic playing surfaces in sport like ASTM(America Society for Testing & Materials) standards of America, DIN 18035 standards of Germany, BSI standards of U.K.

전산유체 기법을 이용한 DAF 부상조에서의 수리 특성 고찰

김성훈,유제선,김영미,박희경 대한상하수도학회 2002 상하수도학회지 Vol.16 No.4

Dissolved air flotation is a solid-liquid separation process that uses fine rising bubbles to remove particles in water. DAF is found most effective in treating algae and lower density flocs that are hard to remove in sedimentation process. Some researcher reports the results of an experimental study which examined the flow within the flotation zone of a DAF tank (ONeill at al., 1997). I would be concluded that, in general, the flow within flotation zone is robust and that differences in the performance of individual DAF tanks must be the result of processes occurring within the contact zones of these tank, not as the result of flotation processes. In this research, the authors thought that the efficiency of the DAF process is strongly related to bubble size. It means bubble rising velocity at the air injection nozzle is most important factor of DAF process. However, bubble movement in DAF tank is somewhat complicate, so it is hard to make up conceptual model through simple mass balance as other researchers did (Leppinen at. al., 2000). For the modeling of turbulent 2-phase flow in the tank, the standard k-ε model was used in CFD code because it is widely accepted and the coefficients for the model are well established. This model uses the eddy-viscosity hypothesis for the turbulence. As the result of this study, the authors concluded that bubble size and its rising velocity is very important factor of DAF process and the recycle ratio must be also consider for the flotation zone parameter. Also, For the improved model, relation between turbulent intensity and bubble-particle attachment must be studied.

전산유체 기법을 이용한 용존공기부상법에서의 접촉도 조건변화에 따른 충돌효율평가

김성훈,유제선,박희경 대한상하수도학회 2004 상하수도학회지 Vol.18 No.2

Dissolved air flotation (DAF) is a solid-liquid separation process that uses fine rising bubbles to remove particles in water. Most of particle-bubble collision occurs in the DAF contact zone. This initial contact considered by the researchers to play a important role for DAF performance. It is hard to make up conceptual model through simple mass balance for estimating collision efficiency in the contact zone because coupled behavior of the solid-liquid-gas phase in DAF system is 90 complicate. In this study, 2-phase(gas-liquid) flow equations for the conservation of mass, momentum and turbulence quantities were solved using an Eulerian-Eulerian approach based on the assumption that very small particle is applied in the DAF system. For the modeling of turbulent 2-phase flow in the reactor, the standard k-ε mode Ⅰ(liquid phase) and zero-equation(gas phase) were used in CFD code because it is widely accepted and the coefficients for the model are well established. Particle-bubble collision efficiency was calculated using predicted turbulent energy dissipation rate and gas volume fraction. As the result of this study, the authors concluded that bubble size and recycle ratio play important role for flow pattern change in the reactor. Predicted collision efficiency using CFD showed good agreement with measured removal efficiency in the contact zone. Also, simulation results indicated that collision efficiency at 15% recycle ratio is higher than that of 10% and showed increasing tendency of the collision efficiency according to the decrease of the bubble size.

물질사용장애 환자의 색다른 것을 추구하는 기질

김미영,박제민,윤경일,유택규,권도훈,김성곤,김명정,장기용 대한생물치료정신의학회 2001 생물치료정신의학 Vol.7 No.1

In this study, the relationship between substance use and high-novelty seeking was tested using Cloninger et al's 240-items Temperament and Character Inventory(TCI) in 34 substance users(32 methamphetamine and 2 cocaine dependence disorders), 80 normal controls and 48 schizophrenics Demographic characteristics and substance use-related past history were taken by semi-structured interview. Subjects were aged 18-45 and general psychopathology was screened by Symptom Checklist 90 revised. The results were as follows. 1) Among temperament subdivisions in the TCI, novelty seeking(NS) was significantly higher in the substance users(22.1±4.9) than the normal controls(18.0±5.0) and the schizophrenics(15.6±3.3). There were no significant differences in other temperament subdivisions such as harm avoidance, reward dependence and persistence, neither character subdivisions such as self-directiveness, cooperativeness and self- transcendence. 2) A significant inverse correlation was found between NS and age both in the substance users(r=0.274) and the normal controls(r=0.468). This study suggested that the biogenetic temperament characteristics in substance use disorder were related with their high novelty seeking, not low harm avoidance.

착화제와 유기산이 Wistar rat체내의 Sr 분포에 미치는 영향

이기호,이제호,박상윤,이승훈,유용운,윤택구 대한방사선 방어학회 1990 방사선방어학회지 Vol.15 No.2

Wistar rat에 85SrCl2를 꼬리 정맥에 주사하여 체내 기관과 혈액 내 분포, 잔존율을 조사하였고 착화제와 유기산을 투여하여 혈장 단백질에 결합하는 Sr양의 변화를 측정하였다. 혈액내에서 Sr은 혈장에 60%, 세포에 40%부착되어 이동하였다. 혈장에 존재하는 Sr중 약 50%정도는 혈장 단백질과 결합한 상태였고, 세표에는 세포 표면에 가볍게 부착되어 있었다. Erythrocyte나 granulocyte보다 lymphocyte에 많은 양의 Sr이 부착되어 있었다. 투여후 초기 1시간 이내에 혈액 내에서 급격히 감소하여 뼈에 침착되었다. 이때 각 기관에서도 Sr의 잔존율은 24시간 이내에 크게 감소하였고, 뼈로 침착된 Sr은 24시간 이후에 서서히 감소하였다. 착화제 EDTA, EGTA 및 DTPA를 투여한 경우, 혈장 단백질에 결합하는 Sr의 양은 대조군의 57%에서 27-33%로 감소하였으며 citrate 및 oxalate의 투여시는 이값이 19%와 40%로 각각 감소하였다. 85SrCl2 was injected to the tail vein of Wistar rats and investigated its distribution and clearance in the tissues and blood. We also measured the changes in Sr binding to the blood plasma protein by administrating chelating agents and organic acids. For the blood, 60% of the Sr occurred in the plasma and 40% on the cell membrane. Fifty percent of Sr in the blood plasma was bound to plasma protein. Sr on the cell membrane seemed to be bound loosely. The binding in the lymphocyte was higher than in the erythrocyte and granulocyte. Within one hour Sr was quickly disappeared from the blood stream, to be accumulated in the bone. Twenty four hours after the injection, Sr decreased rapidly in the organs of soft tissue, but slowly in the bone. The binding of Sr to plasma protien decreased from 57% of the control to 27-33% in the group treated with chelating agents. EDTA. EGTA and DTPA and to 19% and 40% in the groups treated with organic acids, citrate and oxalate, respectively.