• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.42-50
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• 2001

In this paper, the effects of scale formation in engine water jacket upon the thermal durability of engine itself and its component parts were studied. To understand the effect of quality of water, a full load engine endurance test for 50 hours was carried out with not-treated underground water. The followings were found through the tested engine inspection after the endurance test; 1-2 mm thick scale formation in the engine water jacket, valve seat wear, piston top land scuffing, piston pin stick, and cylinder bore scuffing in siamese area. In order to understand the causes of above test results, the heat rejection rate to coolant, the metal surface temperature of combustion chamber, and the oil and exhaust gas temperatures were measured and analyzed. The scale formed in the engine water jacket played a role as thermal insulator. The scale formed in the engine reduced the heat rejection rate to coolant and it caused to increase the metal surface temperature. The reduced heat rejection rate to coolant increased the heat rejection rate to oil and exhaust gas and increased the oil and exhaust gas temperature. Also, the reasons of valve seat wear, piston top land scuffing and cylinder bore scuffing, and piston pin stick quantitatively analyzed in this paper.

• Anxiety and mood
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• v.8 no.2
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• pp.153-160
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• 2012

Objectives : The purpose of this study was to develop an employee's stress response scale (ESRS) and examine its validity and reliability. Methods : The study was conducted as follows : item generation, and test of validity and reliability. Items were developed via literature review, review of instruments, and data acquired from email-survey of counselors in the field of Employee Assistance Program (EAP). In order to test validity and reliability, data were collected from 400 employees. Results : The result of exploratory factor analysis of ESRS suggested 4 factor structures (work-related, anger, somatization, depression & anxiety) with a total of 25 items. ESRS showed a relatively strong positive correlation with Hospital Anxiety-Depression scale (HAD), Perceived Stress Scale (PSS), and Psychological Wellbeing Index (PWI), which showed ESRS had high convergent validity. Cronbach's ${\alpha}$ and test-retest reliability was .95 and .610 respectively. Conclusion : The ESRS is reliable and valid brief scale for measuring stress responses of employees. This scale would be useful in quantitatively evaluating job stress in workplace.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.6
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• pp.415-423
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• 2021

There have been many experimental studies on the manoeuvrability of KRISO Container Ship (KCS). However, the scale ratio of the model ship and the test procedure for each institute are slightly different, so direct comparison for the data is technically difficult to perform. This paper presents the manoeuvrability of the ship with different scale ratios: 1/65.8, 1/42.0, and 1/31.6 in model scale. KRISO conducted Free Running Model Tests (FRMT): 35° turning circle tests and 20/20(10/10) zigzag manoeuvring tests. The test results indicated that advance and tactical diameter in turning circle tests were similar, and overshoot angles in two zigzag manoeuvring tests increased as the model ship size increased. In addition, a basic concept for the FRMT method with an auxiliary X-thrust device was proposed so that the scale effect could be considered in model ship tests.

• The Journal of Korean Physical Therapy
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• v.31 no.1
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• pp.49-55
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• 2019

Purpose: This study examined the effects of taping therapy on the balance and gait of stroke patients. Methods: The subjects of this study were 30 stroke patients. The treatment groups were prescribed a combination of taping, therapy applied simultaneously to the ankle and the hip joint, and general physical therapy twice a day for 30 minutes each, five days per week for 4 weeks for a total of 40 times. The control group was treated with general physical therapy for 30 minutes, 5 times per week for 4 weeks, and total 40 times. All subjects were followed up on a Berg balance scale, timed up and go test, activity-specific balance confidence scale, and GaitRite. Results: The group that simultaneously received taping therapy to the ankle and hip joint showed more significant effects than the group treated with ankle joint taping only (p<0.05). Effects were noted in the Berg balance scale, timed up and go test, activity-specific balance confidence scale and gait ability test. Compared to the control group, the group treated at the ankle and hip joint showed significant effects after the experiment in the Berg balance scale, timed up and go test, activity-specific balance confidence scale, and gait ability test (p<0.05). Conclusion: Taping therapy applied to both the ankle and hip joints, and combined with general physical therapy appears to be effective in patients with chronic stroke who have an impaired balance and gait ability.

• PNF and Movement
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• v.10 no.1
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• pp.1-7
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• 2012

Purpose : To verify the interrater reliability of upper extremity function assessment among three tools(Wolf motor function test, Motor assessment scale, Fugl-meyer assessment scale). Methods : The subjects of this study 40 (20 was physical therapists and 20 was physical therapy students). For the test one patients with chronic hemiparesis after stroke participated in the study. The Wolf Motor Function Test consists of 16 functional tasks. The motor assessment scale consists of 3 functional tasks. The fugl-meyer assessment scale consists of 8 functional tasks. All test sessions were videotaped and scored by 40 subjects. Analysis : The data was analysis by SPSS PC 14.0 with Cronbach alpha Coefficients, intraclass Correlation Coefficients Kendall tau-b value. Results : WMFT was highly scored in Cronbach's value, Cronbach's ${\alpha}=0.819$ that means high interrater reliability among assessment. WMFT was highly scored all items in p-value except one item, that means high p-value between therapists and students. WMFT was highly scored in Intrarater correlation coefficient (ICC) = 0.79, that means high interrater reliability of each examination item. WMFT was low index of coincidence from all items, MAS was low index of coincidence from a tim and FMA was low index of coincidence from 4 items. Conclusion : The interrater reliability of WMFT were compared with MAS, FMA and highly verified. WMFT can be more useful tool among upper extremity function assessment.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.198-203
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• 1995

The objective of this study is to provide the information on the techniques of manufacturing and experiment in small scale modeling of precast concrete(P.C.)large panel structures. The adopted scale was 1/5th 4types of experiments were performed : material tests for model concrete and model reinforcement, compressive test of horizontal joint, shear test of vertical joint and cyclic static test of 2-story subassemblage structure. Based on the experimental results, the following conclusions are drawn: (1)Model concrete may have in general larger compressive strength than expected. (2) Model reinforcement can show less ductility if the annealing processes were performed without using vaccuum tube. (3) Failure modes of horizontal and vertical joints were almost same for both prototype and model. But the strength of model appears to be higher than required by similitude law. (4)Hysteretic behavior of 1/5 scale subassemblage model can be made quite similar to prototype's if the ductility of model reinforcement and compressive strength of model concrete could be representative of those of prototype.

• Korean Journal of Child Studies
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• v.20 no.2
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• pp.3-19
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• 1999

The Revised Classroom Play(RCP) scale was validated for Korean 4th grade students. 104 boys and 80 girls took the translated RCP. Test-retest reliability was established with 41 children after 2 months, and test of criterion-related validation was established by the Social Behavior Scale administered to 71 children. All raw scores were standardized by classroom and sex to adjust for differences in the number of nominators and nominatees. The structure of the RCP resulted in 3 factors, 'sociability-disruptive' and 'shy-isolated', with 28 items similar to the original RCP 3 factors. For criterion-related validity, the correlations between the 3 factors of the RCP and the 3 factors of the Social Behavior Scale were positive. For internal consistencies, Cronbach's ${\alpha}$ of the RCP factors ranged from .77 to .94. Test-retest reliability coefficients ranged from .33 to .51. Analyses of variance revealed good item discrepancies for all 28 items. These results confirm the RCP as a valid and reliable measure of the quality of peer relations.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2011-2014
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• 2008

A linear induction motor for urban railway transit is accompanied with the end-effect and large air-gap comparing with a rotary induction motor. These cause amount of difference between simulation results and experiments. In order to figure out the difference, experiments based on a real-scale test bed are indispensable, however building a test-line and a test vehicle is so difficult that authors are going to make a small-scale model and simulate it for comparison. In this paper, A rotary-type small-scale model of a linear induction motor is designed. Thrust and normal force of the model have been analyzed with the variation of frequency and speed by using a Finite Element Method(FEM).

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2548-2553
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• 2008

Prediction of the rotor blade performance is important for determining design factors such as weight and size in development of a small-scale helicopter. Generally, prediction of helicopter performance means the estimation of the power required for a given flight condition. However, due to lack of test data and analyzed results for small-scale rotor blade operated at low Reynolds numbers ($Re{\approx}10^5$), this is not an easy task. As an initial research, this work performs a modeling of a single rotor configuration with FLIGHTLAB and a experimental research with rotor test bed. In this process, we performed small-scale isolated single rotor by experimental and numerical method and achieved good agreement of the hover performance on the test data and simulation results.

• Journal of Ship and Ocean Technology
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• v.5 no.4
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• pp.44-50
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• 2001

Large container carriers are suffering from lack of knowledge on reliable correlation allowances between model tests and full-scale trials, especially at fully loaded condition, Careful full-scale sea trial with a full loading of containers both in holds and on decks was carried out to clarify it. Model test results were analyzed by different methods but with the same measuring data to figure out appropriated correlations factors for each analysis methods, Even if it is no doubt that model test technique is one of the most reliable tool to predict full scale powering performance, its assumptions and simplifications which have been applied on the course of data manipulation and analysis need a feedback from sea trial data for a fine tuning, so called correlation factor. It can be stated that the best correlation allowances at fully loaded condition for both 2-dimensional and 3-dimensional analysis methods are fecund through the careful sea trial results and relevant study on the large size container carriers.