• Korean Journal of Applied Biomechanics
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• v.27 no.2
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• pp.125-132
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• 2017

Objective: The aim of this study was to investigate the effect of targeted knee flexion angle on biomechanical factors of knee joint between upward and downward phases during the forward lunge. Method: Eight elderly subjects (age: $22.23{\pm}1.51years$, weight: $69{\pm}6.63kg$, height: $174.88{\pm}6.85cm$) participated in this study. All reflective marker data and ground reaction force during a forward lunge were collected. The knee joint movement and reaction force and joint moment at maximum knee flexion angle were compared by repeated measures one-way analysis of variance (ANOVA) (p<.05). The peak knee joint reaction force and joint moment between upward and downward phases were compared by repeated measures two-way ANOVA (p<.05). Results: The anterior and vertical knee joint movements, reaction force, and extensor moment of $80^{\circ}$ targeted knee flexion condition at maximum knee flexion angle was greater than both $90^{\circ}$ and $100^{\circ}$ conditions (p<.05). The $80^{\circ}$ knee flexed angle condition had greater peak joint reaction force and extensor moment compared with both $90^{\circ}$ and $100^{\circ}$ conditions between upward and downward phases during the forward lunge. Conclusion: As the targeted knee joint flexion angle increases, knee joint movement and kinetic variables become greater during the forward lunge exercise.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.6
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• pp.758-766
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• 2005

This study was conducted to evaluate the effect of the transverse troughs on hydrodynamic behavior within the a certain full-scale sedimentation basin (flow rate/one basin; $10,000m^3/d$) using CFD simulation and ADV technique. In order to verify the CFD simulation, we measured the factual velocity at 36 points in the full-scale sedimentation basin, whose outlet structure is inadequate, with ADV technique. Both the CFD simulation and the ADV measurement results were in good accordance with each other. From the CFD simulation results of the existing basin, it was investigated that extreme upward flow occurs in the near of two transverse troughs. It was suspected that since the transverse troughs converted the open channel flow into the local closed pipe flow, the increased pressure in this local closed pipe flow region made the extreme upward flow. For solving this problems, it was suggested to modify transverse-typed launder into finger-typed launder and to install a longitudinal baffle in the center in this study. The CFD simulation results of all suggested amendments told us that the extreme upward flow, had occurred especially in the beneath of transverse troughs, was much less in the case of finger typed launder basin than that in the existing basin. Also, it was predicted that installing a longitudinal baffle made the fully developed flow which is more effective for sedimentation.

• Journal of The Korean Association For Science Education
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• v.14 no.2
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• pp.133-142
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• 1994

Many students have misconceptions that upward direction force act on the object which is moving upward after being thrown vertically upward, and no force act on the object at the top of its flight because the object stop or don't' move at the top. To change these misconceptions, in this study, deductive reasoning tasks were used, and student's responses to the tasks were analyzed. In the first part of this study, student's prior conceptions about force and motion and student's deductive reasoning abilities were investigated. And the second part, student's explanations were classified to either the premise-based or idea-based explanation. In the case of the object which is moving upward, 62% of students who had misconception changed their misconceptions to physically correct concept, but, only 24% of students changed their misconceptions for the object at the top. For the first task, more students changed their misconceptions when they made responses based on premises than based on their own idea(p<.05), so, the first task can be helpful for conceptual change. 40% students changed their own misconception by reasoning deductively based on premises provided in the first task, but only 17% students changed by the second task. Student's reasoning abilities investigated in the first part of this study did not affect the conceptual change. Four students for the first task and one student for the second task did not change their misconception even though they made premise-based explanation and had high reasoning abilities.

• The Korean Journal of Pain
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• v.7 no.2
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• pp.211-216
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• 1994

Celiac plexus block is performed to relieve intractable upper abdominal cancer pain. Generally, celiac plexus blocks have been performed under control of X-ray fluoroscopy to determine the position of the needle tip and the spread of contrast media. During the period from March 1992 to February 1994, we have performed 21 cases of neurolytic celiac plexus block to alleviate pain of intra-abdominal malignancy. We retrospectively evaluated the location of the needle tip and the spread of contrast media. P-A views of simple abdomen demonstrated the locations of the needle tip: 66.7% of the left needle tips were in upper 3/1 of L1 (6 cases) and $T_{12}-L_1$ interspace (8 cases), 50% of the right needle tips were in upper 1/3 of $L_1$, (6 cases) and $T_{12}-L_1$ interspace (4 cases). Contrast media from the right needle spread upward to middle 1/3 of $T_{10}$ (5 cases) and middle 1/3 of $T_{11}$ (5 cases), downward to middle 1/3 of $L_1$ (6 cases) and lower 1/3 of $L_1$ (3 cases). Contrast media from the left needle were spread upward to middle 1/3 of $T_{10}$ (5 cases) and evenly to other spaces, downward to middle 1/3 of $L_1$, (4 cases) and $L_1-L_2$ interspace (6 cases). We analyze the spread of contrast media according to distance from needle tip by authors score system. Contrast media of right needle spread upward 6.1 and downward 3.4, that of left needle spread upward 6.5 and downward 3.7.

• Journal of the Korean Regional Science Association
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• v.36 no.3
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• pp.3-16
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• 2020

The causes and effects of intra-urban spatial inequality have received much scholarly attention. However, the effects of urban spatial inequality on resident perceptions and the mechanisms through which it is sustained and reproduced remain mostly unknown. This study aimed to investigate whether regional deprivation, the relative socioeconomic standing of a region, affects the residents' perceptions of upward social mobility. By employing the ordinal logistic multilevel model to analyze nested data collected from Seoul, South Korea, this study found that the regional deprivation has a significant negative effect on residents' perception of upward social mobility. The results of this study suggest that one way in which spatial inequality is sustained and reproduced is by the effects of regional deprivation, having negative impacts on the aspirations and socioeconomic activities of residents. This study is expected to provide meaningful implications for planning and policy aimed to combat spatial inequality.

• Membrane Journal
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• v.6 no.4
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• pp.203-212
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• 1996

The operating parameters influencing on limiting flux was investigated in the ultrafiltration of PVA, and a new model, which is based on the Amiar model using the concept of heat transfer coefficient, was devised to overcome the limitation of gel-layer model. Using polysulfone plate-unit membrane (MWCO=20,000) and hollow-fiber membrane (MWCO= 30,000), ultrafiltration characteristics of PVA was examined with the variation of operating parameters such as cross flow velocity, transmembrane pressure, temperature, and PVA concentration. According to experimental results, the ultrafiltration of PVA through polysulfone membrane is mainly controlled by well-known phenomena of concentration polarization caused by gel-layer formation. On the contrary, in hollow fiber membrane was observed upward limiting flux which can not be explained by gel-layer model. New model was applied to predict the upward limiting flux behavior with partial satisfaction. The application of new model including viscosity correction factor, however, revealed that PVA ultrafiltration is closely related to the viscosity of permeating fluid.

• Parasites, Hosts and Diseases
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• v.60 no.5
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• pp.327-338
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• 2022

This study determined the recent status and trend of Pneumocystis jirovecii pneumonia (PcP) in the non-human immunodeficiency virus (HIV) (non-HIV-PcP) and HIV (HIV-PcP) infected populations using data from the Health Insurance Review & Assessment Service (HIRA) and the Korea Disease Control and Prevention Agency (KDCA). SaTScan and Join-point were used for statistical analyses. Non-HIV-PcP cases showed an upward trend during the study period from 2010 to 2021, with the largest number in 2021 (551 cases). The upward trend was similar until 2020 after adjusting for the population. Seoul had the highest number of cases (1,597) in the non-HIV-PcP group, which was the same after adjusting for the population (162 cases/1,000,000). It was followed by Jeju-do (89 cases/1,000,000). The most likely cluster (MLC) for the non-HIV-PCP group was Seoul (Relative Risk (RR)=4.59, Log Likelihood Ratio (LLR)=825.531), followed by Jeju-do (RR=1.59, LLR=5.431). An upward trend was observed among the non-HIV-PcP group in the Jeju-do/Jeollanam-do/Jeollabuk-do/Gyeongsangnam-do/Busan/Daejeon/Daegu/Ulsan joint cluster (29.02%, LLR=11.638, P<0.001) located in the southern part of Korea. Both women and men in the non-HIV groups showed an overall upward trend of PcP during the study period. Men in the 60-69 age group had the highest annual percentage change (APC 41.8) during 2014-2019. In contrast, the HIV groups showed a falling trend of PcP recently. Men in the 60-69 age group had the most decrease (APC -17.6) during 2018-2021. This study provides an analytic basis for health measures and a nationwide epidemiological surveillance system for the management of PcP.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2217-2221
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• 2007

Because of the ozone layer depletion and global warming, new alternative refrigerants are being developed. In this study, evaporation heat transfer characteristics of carbon dioxide flowing upward in a vertical tube have been investigated by experiment. Before the test section, a pre-heater is installed to adjust the inlet quality of the refrigerant to a desired value. A smooth tube with outer diameter of 5 mm and length of 1.44 m was selected as a test tube. The test was conducted at mass fluxes of 212 to 530 kg/$m^2s$, saturation temperature of -5 to 20$^{\circ}C$, and heat fluxes of 20 to 45 kW/$m^2$. As the vapor quality and mass fluxes increase, the heat transfer coefficients of carbon dioxide are decreased, and the heat transfer coefficients increase when the heat fluxes and saturation temperatures increase.

• Nuclear Engineering and Technology
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• v.8 no.3
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• pp.139-143
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• 1976

$^{32}$ P was supplied to the roots of stem-ringed 1-year-old apple trees and 2-year-old citrus trees on which bark segments were isolated above and below the ring. $^{32}$ P was translocated to shoots and leaves although considerable translocation occurred especially in wood and bark tissues. The accumulation of $^{32}$ P in isolated bark segments indicated that the occurrence of these materials in this tissue was via radial translocation from xylem tissue, and that the main upward translocation pathway of $^{32}$ P supplied to roots is through the xylem.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.111-121
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• 2015

The objective of this study is to develop an automatic object changer unit to improve changing process problems existing in the conventional horizontal machining center. In order to perform this objective, an upward and downward traverse unit was designed. This unit consists of a motor, reducer, chain and sprocket wheel, and an upper and lower base. This automatic object changer unit performs a sliding contact motion in a purpose built and designed frame. Constraint conditions for the upward and downward traverse unit were first designed. Then, an operation mechanism was designed and introduced as the sum of the kinetic energy for the sprocket wheel and the upper and lower base and which was based on the moment of inertia, which is the kinetic energy of the converted upward and downward traverse unit in the side of the reducer. The paper covers the design of th e Automatic Pallet Changer for th e machining center.