• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.51-61
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• 2012

The new alkali pulping process combined with electron beam treatment was applied to utilize hemp bast tissues as a new valuable fibrous resource. Hemp bast tissues have some chemical properties with high lignin contents and holocellulose not to be defiberized by alkali pulping only, compared with the bast tissue of paper mulberry. To make up for the weakness of traditional alkali pulping process, electron beams were directly irradiated into the swelled bast tissue of hemp in NaOH solution and distilled water, and then facilitated the defiberization of hemp bast tissues. The papermaking from hemp bast fibers manufactured by the combination pulping process showed good apparent density, formation structure and air permeability, and had some mechanical properties with lower tensile, tear, burst strength and folding endurance. It is finally concluded that the combination pulping process with electron beam treatment could be suggested a new alternative for non-woody fibers.

• Structural Engineering and Mechanics
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• v.72 no.2
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• pp.245-256
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• 2019

The experimentally determined mechanical behavior of the material under the prescribed service conditions is the basis of advanced engineering optimum design. To allow experimental data on the behavior of the material considered, uniaxial stress tests were made. The aforementioned tests have enabled the determination of mechanical properties of material at different temperatures, then, the material's resistance to creep at various temperatures and stress levels, and finally, insight into the uniaxial high cyclic fatigue of the material under different applied stresses for prescribed stress ratio. Based on fatigue tests, using modified staircase method, fatigue limit was determined. All these data contributes the reliability of the use of material in mechanical structures. Data representing mechanical properties are shown in the form of engineering stress-strain diagrams; creep behavior is displayed in the form of creep curves while fatigue of the material is presented in the form of S-N (maximum applied stress versus number of the cycles to failure) curve. Material under consideration was 18CrNi8 (1.5920) steel. Ultimate tensile strength and yield strength at room temperature and at temperature of $600^{\circ}C$: [${\sigma}_{m,20/600}=(613/156)MPa$; ${\sigma}_{0.2,20/600}=(458/141)MPa$], as well as endurance (fatigue) limit at room temperature and stress ratio of R = -1 : (${\sigma}_{f,20,R=-1}=285.1MPa$).

• The Journal of Internal Korean Medicine
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• v.43 no.3
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• pp.423-435
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• 2022

Purpose: The purpose of this study was to confirm the clinical efficacy of Gyeongok-go. Methods: Public/Publisher MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), Excerpta Medica dataBASE (EMBASE), Research Information Sharing Service (RISS), ScienceON, Korean Traditional Knowledge Portal (KTKP), and China National Knowledge Infrastructure (CNKI) were searched for randomized controlled clinical trials administering Gyeongok-go as an intervention, published from inception to December 31, 2021. The risk-of-bias of the included trials was assessed with the Cochrane risk-of-bias tool for randomized trials version 2. From the experimental and control groups of the selected trials, the mean value (or rate) of each outcome was extracted and statistically compared. Results: Statistically significant mean differences were in VO₂max (MD 6.82), post-exercise heart rate (MD -8.76 at 5 min, -11.58 at 30 min, -14.6 at 60 min), senescence scale (MD -6.52), Th1 cells and Th2 cells in pulmonary tuberculosis (MD 2.79 and -1.64), yin-deficient and qi-deficient score (MD -9.64 and -9.76), and phlegm-dampness score (MD 5.56). Overall risk-of-bias was 20% low risk, 80% some concerns, and 0% high risk. There were no reports of adverse events. Conclusions: Gyeongok-go is likely to have the effect of improving cardiorespiratory endurance, increasing fatigue recovery ability, reducing senescence, and enhancing immune function in tuberculosis patients. Also, it is more suitable for those who are yin-deficient or qi-deficient, and those with phlegm-dampness probably need caution.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.9
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• pp.78-84
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• 2022

An air circuit breaker (ACB) is an electrical protection device that interrupts abnormal fault currents that result from overloads or short circuits in a low-voltage power distribution line. The ACB consists of a main circuit part for current flow, mechanism part for the opening and closing operation of movable conductors, and arc-extinguishing part for arc extinction during the breaking operation. The driving mechanism of the ACB is a spring energy charging type. The faster the contact opening speed of the movable conductors during the opening process, the better the breaking performance. However, there is a disadvantage that the durability of mechanism decreases in inverse proportion to the use of a spring capable of accumulating high energy to configure the breaking speed faster. Therefore, to simultaneously satisfy the breaking performance and mechanical endurance of the ACB, its driving mechanism must be optimized. In this study, a dynamic model of the ACB was developed using the MDO(Mechanism Dynamics Option) module of CREO, which is widely used in multibody dynamics analysis. To improve the opening velocity, the Taguchi design method was applied to optimize the design parameters of an ACB with many linkages. In addition, to evaluate the improvement in the operating characteristics, the simulation and experimental results were compared with the MDO model and improved prototype sample, respectively.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.111-124
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• 2021

Purpose : The purpose of this study is to evaluate whether physical ability is improved by body stabilization, develop training methods to improve physical fitness factors suitable for body conditions, and provide future management and exercise materials to improve Taekwondo athletes' performance, after conducting the Body stabilization exercise (BSE) program on 22 elementary school Taekwondo athletes for 10 weeks to strengthen core muscles and evaluating Visual response speed test (VRST), Functional movement screen (FMS), Y-Balance test (YBT) and Vital capacity (VC). Methods : In order to examine the impact of the BSE program on Taekwondo athletes' VRST, FMS, YBT and VC this study conducted individual evaluations on all subjects, including VRST, FMS, YBT and VC before applying the programs, and compared exercise effects before and after the program, before and after exercise by a certain period. Results : After exercising, strength and quickness were improved significantly and reaction time was significantly shortened (p<.001). The total score of FMS was improved from 10.86±1.17 before to 11.68±0.99 after exercising, was statistically significant (p=.014). YBT was significantly improved from 91.11±4.84 before to 95.68±5.15 after exercising (p<.001). VC improved was statistically significant (p<.001). Conclusion : In conclusion, the BSE athletic program is expected to help Taekwondo athletes perform well by preventing and reducing injuries through the improvement of muscular strength, strength, speed, agility, step, kick, balance, flexibility, full body endurance and the combination of technical abilities.

• Animal Bioscience
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• v.36 no.2
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• pp.307-314
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• 2023

Objective: Chicken essence and branched chain amino acid (BCAA) supplementation has been recognized to significantly relieve fatigue. To obtain chicken essence with high amounts of BCAA, spent hens herein was used to prepare dripped chicken essence (SCE) and compared with commercial dripped chicken essence (CCE) for in vivo anti-fatigue effect. Methods: To determine the effect on anti-fatigue by dripped chicken essence, the exhaustive swimming was performed. Thirty-two 7-week ICR mice were divided into four groups, which included the control group (CG), CCE, SCE-1X and SCE-2X. The mice were given daily oral administration (0.012 mL/g body weight/d). The fatigue index analysis was conducted weekly. Results: The results showed that SCE had a higher BCAA level as expected, and mice treated with dripped chicken essence (CCE and SCE) could significantly improve exercise performance. The lower blood lactate level, blood urea nitrogen level and creatine phosphokinase activity were found in the supplement of SCE group compared with the CCE group, which suggested that the SCE possessed strong anti-fatigue ability. This could possibly be due to the higher content of BCAA. Conclusion: In this study, SCE promoted recovery from physical fatigue in mice and elevated endurance ability. Among them, the double dose (SCE-2X) showed the strongest anti-fatigue ability. Taken together, spent chickens could be a good source of chicken essence to improve the effect of anti-fatigue.

• Journal of the Korea Society of Computer and Information
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• v.14 no.6
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• pp.1-10
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• 2009

Flash memory has the advantages of nonvolatile, low power consumption, light weight, and high endurance. This enables the flash memory to be utilized as a storage of mobile computing device such as PMP(Portable Multimedia Player). Potable device with a mass flash memory can store various multimedia data such as video, audio, or image. Typical index systems for mobile computer are inefficient to search a form of text like lyric or title. In this paper, we propose a new text index system, named EMTEX(Embedded Text Index). EMTEX has the following salient features. First, it uses a compression algorithm for embedded system. Second, if a new insert or delete operation is executed on the base table. EMTEX updates the text index immediately. Third, EMTEX considers the characteristics of flash memory to design insert, delete, and rebuild operations on the text index. Finally, EMTEX is executed as an upper layer of DBMS. Therefore, it is independent of the underlying DBMS. We evaluate the performance of EMTEX. The Experiment results show that EMTEX can outperform th conventional index systems such as Oracle Text and FT3.

• 대한공업교육학회지
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• v.33 no.2
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• pp.44-71
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• 2008

This paper was intended to investigate employment conditions and career planning of ex-participants of the customized training program(CTP) in Technical High Schools for the specific Small and Medium Business through questionnaires. Results of the research were: 1. The average ex-participant of CTP was employed in small size company with 50 employees, earned 1~1.2 Million Won monthly, worked about 50 hours per week. 2. They were earnestly considering and worried about their career. They had their career goals : Engineer in production and manufacturing, CEO of a company, Design engineer. 3. They were not able to invest enough time and energy in developing their capabilities and skills. 4. There were feelings of respondents, which the main barriers of their career achievement were : (1) their deficiency of personal competencies and endurance. (2) not time enough to learn (3) the fallacy of organizational support and atmosphere.

• Journal of Korean Academy of Nursing
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• v.29 no.4
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• pp.766-779
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• 1999

The purpose of this study was to investigate the relationship between the burden on families who live with an elderly person suffering from senile dementia, and the degree of their depression. There were 400 participants in this study, staying in the Seoul and Kyonggi areas from August 1, 1997 to February 28, 1998. Among the group, 100 participants took care of their patient at home, and another 300 participants left 100 patient at a day-care center, 100 sanatorium for senile dementia(asylum for helpless elderly people), 100 an infirmary for elderly people. Eventually 242 subjects out of the 400 were selected for the data analysis. The Zarit (1980) tool was employed to measure the degree of burden and Zung's(1965) “Self-Rating Depression Scale” was employed for the data analysis. The data was analyzed, and the percentage, t-test, ANOVA and Person's Correlation Coefficient were calculated. The results are as follows : 1. The average degree of burden that care-giving families felt was 49.13, which is somewhat high. 2. The average degree of depression that care -giving families felt was 51.95, which is relatively high. 3. The degree of burden was directly affected by the relation with the patient(F＝2.48, P＜.05), and the socio-economic status of the family(F＝5.17, P＜.05). Its also affected by the patient's educational status(F＝2.17, P＜.05). 4. The degree of depression of the family was significantly dependent on sex(t＝-2.05, P＜.05), age (F＝2.99, P＜.05), the relationship with the patient(F＝3.65, P＜.01), socio-economic status (F＝7.74, P＜.001), occupation(t＝2.82, P＜.01), health status(F＝4.42, P＜.01), and the place of residence(F＝4.30, P＜.01), The patient characteristics was significantly dependent on his/her educational status(F＝3.85, P＜.01), the period of suffering from senile dementia(F＝2.47, P＜.05), and smoking habit(F＝6.17, P＜.001). 5. The relationship between the degree of burden and that of depression reads r＝0.43, which is statistically positive correlation in the high significant level. Upon analyzing the entire summation, most care-givers for elderly patients suffering from senile dementia lack time in caring for themselves. They also experience chronic fatigue and mental discomfort caused by the isolation from society, curtailment of certain activities, a sense of responsibility for their patients, and limits of their endurance in taking care of their patients over time. In conclusion, this study emphasizes the necessity for the following propositions : 1. In order to measure the degree of burden that Korean care-giving families undergo, a new tool must be developed on the basis of Korean culture. 2. An educational program based on the demands that care-giving families undergo must be developed, and its clinical effect also has to be examined.

• Journal of the Korean Applied Science and Technology
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• v.39 no.4
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• pp.568-579
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• 2022

The purpose of this study was to investigate the relationship between physical activity participation habits, physical fitness level, and academic performance among the Reserve Military Training Corps (ROTC). Participants in the current study were 71 ROTCs from J University. Physical activity participation was investigated using the Global Physical Activity Questionnaire (GPAQ), and the level of physical fitness was measured by health-related physical fitness evaluation. For academic performance, university grade data (GPA) was approved by the head of the relevant school district, and the data were collected with the consent of the participants, and each data was analyzed. The correlation between physical activity participation habits, physical fitness level, and GPA was analyzed, and GPA by physical fitness level were compared. This study found that there was no statistically significant correlation between physical activity participation and academic performance. Otherwise, there was a statistically significant correlation between major subjects and total physical fitness score, cardiorespiratory fitness, muscular endurance, flexibility, and body composition. By the level of physical fitness, the ROTCs in the high-physical fitness group showed statistically significantly higher academic performance than the ROTCs in the low-physical fitness group. In addition, low level of physical fitness ROTC group was lower than the other. In conclusion, ROTCs with a high physical fitness level had a positive effect on improving learning ability compared to those who did not. By recommending an autonomous but systematic exercise training program, it is suggested to improve the physical strength of ROTCs and to cultivate excellent future military officers.