• 드라이브 ㆍ 컨트롤
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• 제12권4호
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• pp.48-53
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• 2015

This paper deals with the flow characteristics of a reed valve analyzed using computational dynamics(CFD) for optimal design. The seat sizes of the valve are modeled asØ6[mm] and Ø8[mm] to compare the flow characteristics. The inlet boundary condition is entered at 10[kPa], 15[kPa], 20[kPa], and 30[kPa] and the outlet boundary condition is set to the atmospheric pressure. The flow coefficient(C) and pressure loss coefficient(K) are calculated from the results of flow analysis. From the analysis results, it was confirmed that the flow coefficient of a reed valve having a seat size of Ø6[mm] is greater than that having a seat size of Ø8[mm], and the coefficient of pressure loss of a valve with a seat size of Ø6[mm] is lower than the Ø8[mm] size valve.

• 보건교육건강증진학회지
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• 제32권1호
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• pp.67-76
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• 2015

Objectives: This study performed to verify Korea National Health and Examination Survey(KNHAES) to monitor recommended physical activity(PA) and to propose an monitoring tools for evidence-based PA projects. Methods: The characteristics of the Global Physical Activity Questionnaire(GPAQ) and its reliability and validity were overviewed based on the current scientific evidence in the field of PA. Relevant articles were identified through multiple sources including PubMed, Science Direct, Scopus, CINAHL, ASP, RISS4U, and KISS. Results: The GPAQ has strong points over the Short Form of International Physical Activity Questionnaire(IPAQ-SF) as a monitoring tool to meet recommended PA levels for three domains separately and reflecting a better understanding about walking. Its reliability and validity also were reported as acceptable in existing studies overall. Some limitations of this questionnaire, however, need to be addressed to improve its quality. Conclusions: For monitoring of evidenced-based physical activity projects, we considered that it is able to be provided an opportunity for in-depth discussion among academic experts and policy-makers about the necessity of complements for KNHAES and applying new tools, and it could be the basis for development of physical activity monitoring tool in the future.

• 대한기계학회논문집A
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• 제36권6호
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• pp.637-644
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• 2012

증기 발생기 내부의 U-tube와 지지 구조간의 충격에 의하여 발생하는 프레팅 마모는 원자력 발전소 안전성에 영향을 미치게 된다. 증기발생기의 신뢰성을 향상시키기 위하여 이러한 프레팅 마모 현상을 평가하는 것이 필요하며, 본 연구는 프레팅 마모현상을 정성적, 정량적으로 규명하기 위하여 증기발생기의 실제 상황과 같은 조건의 온도와 압력하에서 실험을 수행하였다. 다양한 실험조건에 대하여 기본적인 실험을 수행하였으며 일률과 마모량의 관계를 온도에 따라 구하였다. $90^{\circ}C$, $200^{\circ}C$, $340^{\circ}C$ 각각의 온도에서의 마모상수는 $9.051{\times}10^{-16}\;Pa^{-1}$, $3.009{\times}10^{-15}\;Pa^{-1}$, $2.235{\times}10^{-15}\;Pa^{-1}$로 구해졌으며 특히 저온 수중상태의 마모상수는 물의 점도의 영향으로 상온 공기중의 값보다 작은 것으로 나타났다.

• Journal of Korean Neurosurgical Society
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• 제63권4호
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• pp.495-503
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• 2020

Objective : Thyroid-stimulating hormone (TSH)-secreting pituitary adenoma (PA) is an extremely rare functioning form of PA that accounts for 0.7-2% of all such cases. The previously reported outcomes of the surgical removal of TSH-PA are poor. Owing to its extremely low incidence, most available reports on TSH-PA are case reports or small case series. Thus, we investigated the clinical and endocrinological outcomes of surgically treated TSH-PA through our institutional series. Methods : We retrospectively reviewed 14 consecutive cases of surgically treated TSH-PA, focusing on the clinical, radiological, surgical, and endocrinological data. Results : There were seven male (50%) and seven female (50%) patients. The mean age was 42.5 years (range, 19-63). The mean tumor size was 16.6 mm (range, 4-30). Optic chiasm compression was noted in six patients (42.9%), and no patient showed cavernous sinus invasion. Thirteen of 14 patients (92.8%) underwent transnasal transsphenoidal approach (TSA), and one patient underwent TSA followed by transcranial approach for residual tumor removal. Thirteen of 14 patients (92.8%) showed endocrinological remission; all patients who experienced remission showed subnormal levels of TSH (<0.4 μU/mL) on postoperative day 2. Recurrence occurred in two patients (14.2%). One patient underwent subsequent revision transnasal TSA for recurrent tumor removal, and the other patient underwent gamma knife radiosurgery for recurrence. Conclusion : Surgical treatment showed excellent surgical outcomes. The TSH level in the immediate postoperative period may be a predictor for endocrinological remission.

• The Journal of Korean Physical Therapy
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• 제34권3호
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• pp.116-120
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• 2022

Purpose: This study aimed to determine which interventions are effective in increasing hamstring flexibility due to changes in the range of motion (ROM) and pennation angle (PA) when foam rolling (FR) and proprioceptive neuromuscular facilitation (PNF) stretching were performed. Methods: A total of 24 healthy participants who agreed to participate in the study were randomly chosen. The participants were divided into three groups of eight people: Control, FR, and PNF stretching groups. The hip flexion angle (ROM) and PA of the hamstrings were measured before and after the experiment. The Wilcoxon signed-rank test was used to analyze the ROM and PA for each group by comparing the before and after results. The Kruskal-Wallis test and the Mann-Whitney U test were used to analyze the increase in hamstring flexibility between the groups. Results: A statistically significant difference was observed in the ROM and PA within all groups, and only the ROM was significant in the comparison between the three groups. In the comparison between the control and other two groups, a significant difference was noted in both the ROM and PA in the FR group and only the ROM in the PNF stretching group (p<0.05). In the comparison between the FR and PNF stretching groups, no significant difference was observed (p>0.05). Conclusion: These findings FR and PNF stretching increased the ROM; however, no change in PA was observed. Therefore, FR and PNF stretching were considered effective interventions in immediately increasing hamstring flexibility.

• Journal of Gastric Cancer
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• 제4권4호
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• pp.207-212
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• 2004

목적: 고형암이 주위조직으로의 침윤과 타장기로의 전이에는 단백분해효소의 활동이 필요하다. Urokinase type plasminogen activator (uPA)는 serine proteinase의 하나로 세포주의 단백분해와 혈관형성에 중요한 물질로서 고형암의 침윤과 전이에 중요한 역할을 한다. uPA는 유방암, 폐암, 방광암, 위암, 직장결장암, 난소암, 및 연조직 육종에서 중요한 예후지표로 알려져 있다. 본 연구에서 저자들은 위암 조직과 정상 점막에서 uPAR유전자의 발현양상에 대해서 조사하고 기존에 알려진 예후인자와의 연관성을 비교 분석하여 향후 중요한 분자학적 치료 target으로의 역할로서의 의의를 살펴보고자 한다. 대상 및 방법: 1997년 5월 이후 위암으로 진단되어 근치적 혹은 고식적 위장절제술을 시행한 위암 환자 35명을 대상으로 하였다. Northern blot analysis와 RT-PCR을 통해 uPAR mRNA의 발현을 확인하였으며, RNA추출을 위한 재료는 위장절제술 직후 종양조직과 동결절편 생검상 종양세포가 없는 것으로 확인된 부위의 정상 위암 조직을 동일 환자로부터 추출하였다. 이들 환자의 육안적 소견, 조직학적 소견, 생존율 등은 내시경과 수술보고서 병리보고서, 병록지 등을 참고하였다. 결과: uPAR mRNA의 expression과 환자의 예후와의 관계를 평가하기 위해서, gene expression과 이미 확립된 clinicopathologic prognostic와의 관계를 비교하였다. 이러한 factor를 중에서 uPAR mRNA expression은 림프절 전이 여부 (P=0.03), TNM stage (P=0.01)와는 일정한 연관성이 있음을 보였으며, 나이나 성별, 종양크기, histologic type, Lauren classification, Ming classification, serosa invasion, vascular invasion, lymphatic vessel invasion, Neural invasion, omental invasion, macroscopic type와는 상관관계를 보이지 않았다. 결론: 종양 세포에서 uPAR를 평가하는 것은 위암의 예후 뿐만 아니라 질병의 재발을 예측하는데 사용될 수 있을 것으로 생각된다.

• Nuclear Engineering and Technology
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• 제43권2호
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• pp.159-166
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• 2011

Si-rich-layer-coated U-7 wt%Mo plates were prepared in order to evaluate the diffusion barrier performance of the Si-rich layer in U-Mo vs. Al interdiffusion. Pure Si powder was used for coating the U-Mo plates by annealing at $900^{\circ}C$ for 1 h under vacuum of approximately 1 Pa. Si-rich layers containing more than 60 at% of Si were formed on U-7 wt%Mo plates. Diffusion couple tests were conducted in a muffle furnace at $560-600^{\circ}C$ under vacuum using Si-rich-layer-coated U-Mo plates and pure Al plates. Diffusion couple tests using uncoated U-Mo plates and Al-(0, 2 or 5 wt%)Si plates were also conducted for comparison. Si-rich-layer coatings were more effective in suppressing the interaction during diffusion couple tests between coated U-Mo plate and Al, when compared with U-Mo vs. Al-Si diffusion couples, since only small amounts of Al in the coating could be found after the diffusion couple tests. Si-rich-layer-coated U-7wt%Mo particles were also prepared using the same technique for U-7 wt%Mo plates to observe the microsturctures of the coated particles.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.185-191
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• 2010

Plasminogen activators (PAs) are serine protease that cleave plasminogen to form the active protease plasmin and may participate in mammalian fertilization. Although correlations have been reported between reactive oxygen species (ROS) and sperm function, the relationship between PA activity and ROS is unknown. We determined the effects of ROS on sperm function and PA activities in boar spermatozoa preincubated under the X-XO system. When spermatozoa were treated with the X+XO group, a significant increase (p<0.05) was observed in the percentage of acrosome reacted spermatozoa compared with that of the control group. However, when antioxidants were added to the medium with X+XO, the rate of acrosome reaction tended to decrease. Also, a significantly lower percentage of acrosome reacted spermatozoa was observed in the X+XO+catalase group at 6 hr of incubation compared with that of X+XO group. The density of malondialdehyde (MDA) was higher in the X+XO group than in different treatment groups. In another experiment, incubation of spermatozoa in medium with X+XO was associated with a significant (p<0.05) increase in activity of tPA-PAI and tPA compared with the control group. Antioxidants decreased the increased activity of tPA-PAI and tPA by preincubation in the X-XO system. Also, a significantly lower (p<0.05) activities of tPA-PAI and tPA were observed in the X+XO+catalase group compared with the X+XO group. No significant differences, however, were observed in the activity of uPA. These results suggest that the increase of acrosome reaction by the X-XO system resulted in increase of PAs activity in the sperm incubation medium.

• 성인간호학회지
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• 제12권1호
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• pp.122-133
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• 2000

The purpose of this study was to identify the effect of body positioning on $PaO_2$, $SpO_2$, systolic blood pressure, diastolic blood pressure, pulse, and respiration(above all defined physiologic index), of patients with unilateral lung disease. The subjects for this study were eleven patients admitted to I.C.U. of K.H.M.C. with a diagnosis of unilateral lung disease confirmed by chest X-ray and the attending doctor, from January 30th. to April 20th. 1999. A quasi-experimental repeated-measures cross-over design was used to compare three body positions(semi-Fowler's, lateral decubitus with good lung dependent, and lateral decubitus with diseased lung dependent). Each subject spent 30 minutes in semi-Fowler's position and 2 hours in good lung dependent position and diseased lung dependent position. Starting in the semi-Fowler's position, then in the lateral position with the good lung dependent or the diseased lung dependent as assigned in random order. Thirty minutes after each positioning, arterial blood sample was analyzed. Measurements of all physiologic index were recorded at the specified intervals(0, 30, 60 90, and 120 minutes) in good lung dependent and diseased lung dependent position. Statistical comparison of $PaO_2$ value was done using the Wilcoxon Signed Rank Test, and Multivariate repeated-measures analysis of variance was performed to analyse the within-subject effect of two dependent position for 2 hours on the five dependent variables: (1) $PaO_2$ (2) $SpO_2$ (3) systolic blood pressure (4) diastolic blood pressure (5) pulse. The results obtained were as follows: 1. The $PaO_2$ value in the good lung dependent position was significantly higher than the $PaO_2$ value in the diseased lung dependent position(Z=-2.8451, p=.002). 2. The $PaO_2$ value in the good lung dependent position was significantly higher than the $PaO_2$ value in the semi-Fowler's position (Z=-2.6673, p=.003). 3. The difference between the $PaO_2$ value in the semi-Fowler's position and the $PaO_2$ value in the diseased lung dependent position was not significant(Z=-1.2448, p=.10). 4. There were no statistically significance in the trends of physiologic index in the good lung dependent position and the diseased lung dependent position. From the results, it may be concluded that the good lung dependent position is the most effective position for patients with unilateral lung disease that improve oxygenation. Identification of positioning over time may be need further studies.

• Bioinformatics and Biosystems
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• 제1권2호
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• pp.115-122
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• 2006

A three-dimensional pharmacophore model was developed based on 24 currently available inhibitors, which were rationally selected from 472 compounds with diverse molecular structure and bioactivity, for generating pharmacophore of uPA (Urokinase Plasminogen Activator) inhibitors. The best hypothesis (Hypo1) comprised of five features, namely, one positive ionizable group, one hydrogen-bond acceptor group and three hydrophobic aromatic groups. The correlation coefficient, root mean square deviation and cost difference were 0.973, 0.695, and 94.291 respectively, suggesting that a highly predictive pharmacophore model was successfully obtained. The application of the model showed great success in predicting the activities of 251 known uPA inhibitors (test set) with a correlation coefficient of 0.837, and there was also none of the outcome hypotheses that had similar cost difference and RMS deviation (RMSD) with that of the initial hypothesis generated by Cat-Scramble validation test with 95% confidence level. Accordingly, our model should be reliable in identifying structurally diverse compounds with desired biological activity.