• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.518-521
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• 2004

The degradation characteristics of MgO protective layer and phosphors have been investigated in terms of the ion-induced secondary electron emission coefficient ${\gamma}$ and static margin of discharge voltages, respectively, in this experiment. The ion-induced secondary electron emission coefficients ${\gamma}$ for the degraded MgO protective layer and phosphors have been studied by ${\gamma}$ -focused ion beam system. The energy of Ne+ ions used is from 80 eV to 200 eV in this experiment. The degraded MgO and phosphor layers are found to have higher ${\gamma}$ than that of normal ones without degradations or aged one. Also, the static margin of discharge voltages for test panels with degraded MgO protective layer and phosphors been found to be seriously decreased in comparison with those of normal ones without degradations.

• 대한기계학회논문집A
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• 제26권6호
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• pp.1178-1186
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• 2002

Clean stockers are being used by semiconductor and TFT-LCD manufacturers to store and buffer work in process. The only way to keep the stored product clean is to provide constant clean airflow the product and through stocker. Up to now, stockers typically have been configured to receive their laminar airflow from fan filter units that are located on the side of the stocker. This type of stocker may have such problems as complexity of structure, increment of temperature, mechanical vibration, initial investment and running cost. In this study, in order to solve the above mentioned problems, new air control system in stocker is proposed, which is to control open ratios of exits that are located on the side of the stocker without fan filter units. In this study, static pressure regain was used for the analysis of the open ratios of exits theoretically and experiment was also conducted using actual clean stocker for TFT-LCD manufacturers and CFDesign, was used for simulating airflow in stocker. As a result, open ratios of exits can be obtained by the analysis of static pressure regain and was verified by experiment and simulation results. Therefore, new air control system in stocker can be used by the semiconductor and TFT-LCD manufacturers.

• Advanced Composite Materials
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• 제16권1호
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• pp.45-61
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• 2007

This paper describes a damage accumulation mechanism in cross-ply CFRP laminates $[0_2/90_2]_{2S}$ subjected to out-of-plane loading. Drop-weight impact and static indentation tests were carried out, and induced damage was observed by ultrasonic C-scan and an optical microscope. Both tests gave essentially the same results for damage modes, sizes, and load-deformation history. First, a crack occurred in the bottom $0^{\circ}$ layer accompanying some delamination along the crack caused by bending stress. Then, transverse cracks occurred in the middle $90^{\circ}$ layer with decreasing contact force between the specimen and the indenter. Measured local strains near the impact point showed that the stress state changed from a bending dominant state to an in-plane tensile dominant state. A cohesive interface element was used to simulate the propagation of multiple delaminations and transverse cracks under static indentation. Two types of analytical models are considered, one with multiple delaminations and the other with both multiple delaminations and transverse cracks. The damage obtained for the model with only multiple delaminations was quite different from that obtained from the experiment. However, the results obtained from the model with both delaminations and transverse cracks well explain the characteristics of the damage obtained in the experiment. The existence of the transverse cracks is essential to form the characteristic impact damage.

• 혜화의학회지
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• 제19권2호
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• pp.35-42
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• 2011

The purpose of this study is to evaluate the difference about pathogenesis of skin type. the theory that explains each individual react to certain stress is generally accepted in traditional oriental medicine. The aim of this experiment is to find out relationship between the effect of facial condition and the vital conditions of traditional Oriental medicine. We recognized that pattern identification of fluid-humor could be divided into 4 different groups. The reason is that the fluid-humor could be interpreted as Qi & Blood, furthermore Qi & Blood were categorized into deficiency and excess groups. Korean female volunteers in good health participated in this experiment. Three doctors of Oriental medicine classified them into 4 groups based on qi-blood and deficiency-excess concept(qi-deficiency; qi-excess:qi-stagnation; blood-deficiency; blood-excess:static-blood). Volunteers were assessed with non-invasive skin measuring devices. And we analyzed the correlation of skin physiological parameters with vital conditions; moisture, sebum and elasticity. Measurement moisture and sebum of facial skin tended to deacease only in static blood group.

• 대한물리치료과학회지
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• 제18권3호
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• pp.93-99
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• 2011

Purpose : In order to investigate the effects of balance training on patients with degenerative arthritis. Methods : 30 participants aged 60 or older participated in balance training for an 8-week period. The effects of the balance training were measured by the visual analog scale(VAS) and static and dynamic balancing. The following are the results of the study. Results : There were no statistically significant differences in measurements of pain when control group participants were at rest and while walking as measured by VAS, but there were statistically significant reductions for the experiment group. Within the control group, there were no statistically significant differences between pretest and posttest results for opened and closed-eye static balance index and visual dynamic balance index. However, within the experiment group, there were statistically significant differences between pretest and posttest results for opened and closed-eye static and dynamic balance indices. Conclusion : The results above provide evidence that balance training effects pain and balance of patients with osteoarthritis and aids in functional movement.

• Corrosion Science and Technology
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• 제21권2호
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• pp.138-146
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• 2022

The cavitation and potentiodynamic polarization experiments were conducted simultaneously to investigate the effect of cavitation amplitude on the super austenitic stainless steel (UNS N08367) electrochemical behavior in seawater. The results of the potentiodynamic polarization experiment under cavitation condition showed that the corrosion current density increased with cavitation amplitude increase. Above oxygen evolution potential, the current density in a static condition was the largest because the anodic dissolution reaction by intergranular corrosion was promoted. In the static condition, intergranular corrosion was mainly observed. However, damage caused by erosion was observed in the cavitation environment. The micro-jet generated by cavity collapse destroyed the corrosion product and promoted the repassivation. So, weight loss occurred the most in static conditions. After the experiment, wave patterns were formed on the surface due to the compressive residual stress caused by the impact pressure of the cavity. Surface hardness was improved by the water cavitation peening effect, and the hardness value was the highest at 30 ㎛ amplitude. UNS N08367 with excellent mechanical performance due to its high hardness showed that cavitation inhibited corrosion damage.

• Clinical and Experimental Reproductive Medicine
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• 제48권2호
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• pp.111-123
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• 2021

Objective: Using domestic cats as a biomedical research model for fertility preservation, the present study aimed to characterize the influences of ovarian tissue encapsulation in biodegradable hydrogel matrix (fibrinogen/thrombin) on resilience to cryopreservation, and static versus non-static culture systems following ovarian tissue encapsulation and cryopreservation on follicle quality. Methods: In experiment I, ovarian tissues (n=21 animals; 567 ovarian fragments) were assigned to controls or hydrogel encapsulation with 5 or 10 mg/mL fibrinogen (5 or 10 FG). Following cryopreservation (slow freezing or vitrification), follicle viability, morphology, density, and key protein phosphorylation were assessed. In experiment II (based on the findings from experiment I), ovarian tissues (n=10 animals; 270 ovarian fragments) were encapsulated with 10 FG, cryopreserved, and in vitro cultured under static or non-static systems for 7 days followed by similar follicle quality assessments. Results: In experiment I, the combination of 10 FG encapsulation/slow freezing led to greater post-thawed follicle quality than in the control group, as shown by follicle viability (66.9%±2.2% vs. 61.5%±3.1%), normal follicle morphology (62.2% ±2.1% vs. 55.2%±3.5%), and the relative band intensity of vascular endothelial growth factor protein phosphorylation (0.58±0.06 vs. 0.42±0.09). Experiment II demonstrated that hydrogel encapsulation promoted follicle survival and maintenance of follicle development regardless of the culture system when compared to fresh controls. Conclusion: These results provide a better understanding of the role of hydrogel encapsulation and culture systems in ovarian tissue cryopreservation and follicle quality outcomes using an animal model, paving the way for optimized approaches to human fertility preservation.

• 한국항공우주학회지
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• 제45권7호
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• pp.574-580
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• 2017

항공기에는 비행 중 공기 중으로부터 축적된 정전기를 방출시키기 위하여 정전기방출기를 장착하여야 한다. 특히 정전기 방출기에 의해 방출되지 않으면, 항공기 표면에 이온화현상이 발생하게 되고, 그에 따라 항공기 외부로 돌출된 안테나 및 날개 끝부분에서 코로나 현상을 발생시켜 무선통신 및 장비운용에 영향을 미치게 한다. 본 논문에서는 항공기 정전기 방출기를 장착하기 위하여 항공기 표면적과 속도 그리고 기후조건을 분석하였다. 또한 그 분석결과를 바탕으로 정전기 방출기 장착설계를 수행할 수 있으며, 장착된 정전기 방출기의 기능시험을 통하여 효과적으로 장착설계가 되어있음을 확인할 수 있다. 그리하여 본 연구결과를 바탕으로 추후 다양한 크기와 임무조건을 가지는 항공기의 정전기 방출기 장착설계를 최적화하여 수행할 수 있다.

• Industrial Engineering and Management Systems
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• 제10권3호
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• pp.185-190
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• 2011

A driver interacts directly with the car seat at all times. There are ergonomic characteristics that have to be followed to produce comfortable seats. However, most of previous researches focused on either static or dynamic condition only. In addition, research on car seat development is critically lacking although Malaysia herself manufactures its own car. Hence, this paper integrates objective measurements and subjective evaluation to predict seat discomfort. The objective measurements consider both static and dynamic conditions. Steven's psychophysics power law has been used in which after expansion; ${\psi}\;=\;a+b{\varphi}_s^{\alpha}+c{\varphi}_v^{\beta}$ where ${\psi}$ is discomfort sensation, ${\varphi}_s^{\alpha}$ is static modality with exponent ${\alpha}$ and ${\varphi}_v^{\beta}$ is dynamic modality with exponent ${\beta}$. The subjects in this study were local and the cars used were Malaysian made compact car. Static objective measurement was the seat pressure distribution measurement. The experiment was carried out on the driver's seat in a real car with the engine turned off. Meanwhile, the dynamic objective measurement was carried out in a moving car on real roads. During pressure distribution and vibration transmissibility experiments, subjects were requested to evaluate their discomfort levels using vehicle seat discomfort survey questionnaire together with body map diagram. From subjective evaluations, seat pressure and vibration dose values exponent for static modality ${\alpha}$ = 1.51 and exponent for dynamic modality ${\beta}$ = 1.24 were produced. The curves produced from the $E_{q.s}$ showed better $R_{-sq}$ values (99%) when both static and dynamic modalities were considered together as compared to Eq. with single modality only (static or dynamic only R-Sq = 95%). In conclusion, car seat discomfort prediction gives better result when seat development considered both static and dynamic modalities; and using ergonomic approach.

• 한국소음진동공학회논문집
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• 제20권8호
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• pp.727-733
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• 2010

Optical tables provide a platform for the establishment and test of measurement systems which use Laser. Therefore, not only static characteristics such as surface flatness, static stiffness and etc. but dynamic response characteristics is very important design parameter. The dynamic stiffness is generally estimated through the modal test, and compliance is used as a representative performance standard. Recently there is an example of defining the dynamic deflection coefficient and using it as a new performance standard of the dynamic stiffness, but it is not generalized yet in industry. In this study, we verify the validity of existing DDC calculus by making an experiment on granite. And for improvement in damping performance of optical tables, we are going to evaluate the effect of fillers on the compliance, then develop an epoxy adhesive based on the result of this experiment.