• Journal of Life Science
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• v.21 no.3
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• pp.400-405
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• 2011

Autophagy, a highly conserved mechanism of internal quality control, is essential for the maintenance of cellular homeostasis and for the orchestration of an efficient cellular response to stress. During aging, the efficiency of autophagic degradation declines and intracellular waste products accumulate. Therefore, the aim of this study is to investigate the effects of exercise on autophagic response in skeletal muscle. Twenty-four Young (4 month) and Old (12 month) ICR-type white male mice were divided into a control group (CON: n=6) and exercise training group (Tr: n=6) after an adaptation period of 1 week. Exercise consisted of treadmill running at 16.4 m/min with a 4% incline, 40 min/day and 5 days/week for 8 weeks. Cervical dislocation was performed at 48 hours after the last round of exercise, after which the gastrocnemius skeletal muscle were immediately collected. The results of verifying autophagy formation showed that the Sarcopenia index was decreased in the Old mice compared to the Young. However, it increased with exercise training in the Old. Lipidation LC3-II, Becline-1, and Atg7 were decreased in the Old mice compared to the Young. However, Lipidation LC3-II was significantly increased in the trained Old mice (Young:1 Vs Old:$1.32{\pm}0.042$, p<0.05). Based on these data, we suggest that autophagy regulatory events are the attenuated in Old mice, but that they are enhanced with exercise training.

• KIEE International Transaction on Systems and Control
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• v.2D no.2
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• pp.78-91
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• 2002

In the thermal power plant, there are six manipulated variables: main steam flow, feedwater flow, fuel flow, air flow, spray flow, and gas recirculation flow. There are five controlled variables: generator output, main steam pressure, main steam temperature, exhaust gas density, and reheater steam temperature. Therefore, the thermal power plant control system is a multinput and output system. In the control system, the main steam temperature is typically regulated by the fuel flow rate and the spray flow rate, and the reheater steam temperature is regulated by the gas recirculation flow rate. However, strict control of the steam temperature must be maintained to avoid thermal stress. Maintaining the steam temperature can be difficult due to heating value variation to the fuel source, time delay changes in the main steam temperature versus changes in fuel flow rate, difficulty of control of the main steam temperature control and the reheater steam temperature control system owing to the dynamic response characteristics of changes in steam temperature and the reheater steam temperature, and the fluctuation of inner fluid water and steam flow rates during the load-following operation. Up to the present time, the Proportional-Integral-Derivative Controller has been used to operate this system. However, it is very difficult to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error. This paper focuses on the characteristic comparison of the PID controller and the modified 2-DOF PID Controller (Two-Degrees-Freedom Proportional-Integral-Derivative) on the DCS (Distributed Control System). The method is to design an optimal controller that can be operated on the thermal generating plant in Seoul, Korea. The modified 2-DOF PID controller is designed to enable parameters to fit into the thermal plant during disturbances. To attain an optimal control method, transfer function and operating data from start-up, running, and stop procedures of the thermal plant have been acquired. Through this research, the stable range of a 2-DOF parameter for only this system could be found for the start-up procedure and this parameter could be used for the tuning problem. Also, this paper addressed whether an intelligent tuning method based on immune network algorithms can be used effectively in tuning these controllers.

• Journal of dental hygiene science
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• v.11 no.6
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• pp.563-571
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• 2011

The purpose of this study was to identify the major variables against oral health promotion behaviors for collegian in Ulsan area. The measured variables for the oral promotion behaviors presently are previous oral health experience, stress by study, subjective oral health, perceived benefit, perceived barrier, self-esteem, self-efficacy, social support, oral health LOC(locus of control), life satisfaction, emotion and intension based on the Pender's 3th health model as a theoretical model in general health promotion behavior. Total data 330 were analyzed by SPSS 18.0 and AMOS 18.0 program and path analysis method was used to verify the model's fitness. Results for this study were as follows: Firstly, the fitness degrees of research model was ${\chi}^2=39.06$(P>.05), GFI = .982, AGFI = .948, NFI = .967, NNFI = .982, RMSR = .028, so it was apparent that this model was well fitted. Secondly, 27 out of 39 total paths were turned out correspond with the hypothetical model which accepted as direct effect. And two paths had statistical significance in direct. Thirdly, the most positive influences on the oral health promotion behaviors presently were previous oral health experience, subjective oral health, social support, self-efficacy, intension, oral health LOC. And the most negative influences was perceived barrier. So, results from this model we could contribute to identify theirs oral health behavior patterns for collegian in Ulsan.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.821-831
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• 2013

As a result of recent research, it is reported that the periodic replacements criterion of rails is able to extend as grinding rail surface and using the continuous welded rail (CWR). In this study, we carried out fatigue tests on existing laid rails. Based on the test results, an S-N curve expressing the remaining life of laid rails at a fracture probability of 50% was obtained using weighted probit analysis suitable for small-sample fatigue data sets. As rails used for testing had different histories in terms of accumulated tonnage, the test data were corrected to average out the accumulated tonnage. We estimated the remaining service lives for laid rails on the urban railway using equations developed in the past to estimate rail base bending stress and that surface irregularities into consideration. Therefore, estimating the remaining service life of laid rails showed that the rail replacement period could be extended over 200 MGT, although it is necessary to remove longitudinal rail surface irregularities at welds by grinding. Also, the fatigue test results under fatigue limit, Haibach's rule appling half slope of S-N curve under the fatigue limit was considered more reasonable than modified Miner's rule for estimating rail fatigue life.

• Korean Journal of Occupational Health Nursing
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• v.13 no.2
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• pp.104-117
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• 2004

Objectives: To propose the basic data for the development of the optimum health promotion program (HPP) for the workers in a petrochemical industry complex. Methods: The subjects were 553 workers who worked at the six plants in a petrochemical industry complex. From February to March 2003, questionnaire survey was conducted by the nurses with occupational health specialty about the life styles, interests, self-cognitions, practices of health behavior, subjective symptoms thought to be related the working environments, burden to the own health, needs and intentions to participation of the HPP. Data analysis was done using SPSS program (ver 10.0) with ${\alpha}=0.05$ of statistical significance. Results: The mean age and tenure of the subjects were 39.7 years and 14.2 years, respectively, and proportion of smokers was around 50%. Two of third (66%) satisfied their own job, and 58% recognized themselves healthy. The most frequent health behavior were exercise (60%) and regular health check (87%) in individual and job based, respectively. About half of them (58%) had at least one of the symptoms thought to be related the working environments, and the most frequent one was odor (21%). These symptoms were more frequent in case of the shorter career. The needs of HPP was relatively higher in exercise (66%), cancer prevention (51%), stress control (47%), and intention to participation was also the highest in exercise (64%). Job satisfaction was higher in case of the higher interests and cognitions to their own health, and thought that the ownership's interest to workers' health be high (p<0.01), but no associations with the subjective symptoms. The mean level of burden to the own health were $14.1{\pm}13.9$ of physical, $11.7{\pm}13.6$ of emotional, $9.1{\pm}10.7$ of behavioral as out of one hundred. They felt the more burden in case of office workers, the lower interests and cognitions to their own health, the lower satisfaction to their job, the frequent drinking group, and complained the subjective symptoms (p<0.05). Abnormal results of the regular health check was higher in the frequent drinking group (p=0.083). Conclusions: For the optimum HPP for the workers in the petrochemical complex, the ownership's interest to workers' health would be enhanced, and the priority would be focused on exercise and drinking habits control.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.470-485
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• 2000

The purpose of this study was to investigate health promotion lifestyle profiles of the Korean elderly in Japan. The subjects of this study were 202 elders in Aichi prefecture. The method of this study questionnaires interviews, and a self-administered questionnaire from the 1st to the 20th of April in 2000. This study tool was based on Walker et al. (1987)'s Health Promotion lifestyle Profiles (HPLP). Analysis of the data used an SPSS/pc+ WIN 9.0 program. Data analyses were conducted by using frequency, percentage, t-test, ANOVA. Pearson correlation, Kendal tau and Stepwise Multiple Regression. The results were as follows: 1. The average score of Health Promotion Lifestyle Profiles of Korean elderly in Japan was 2.72(SD=0.40). On the sub-scale of Health Promotion Lifestyle Profiles: nutrition(M = 3. 06), self-actualization(M =2.99), interpersonal support (M=2.81), stress management (M=2.68) revealed higher scores, whereas the scores of health responsibility(M=2.52), and exercise(M=1.92) were lower. 2. Health Promotion Lifestyle Profiles were significantly different by age (F = 11. 02, p = .000), religion(F=2.96, p=.033), occupation(F=6.91, p=.000), living family status(F=13.07, p=.000), living family number(F=11.74, p=.000), monthly pocket money(F=18.79, p=.000), the source of pocket money (F=7.18, p=.000), and the length of residence(F=9.79, p=.000). 3. Health Promotion Lifestyle Profiles was significantly predicted by monthly pocket money($r^2$ change =0. 188, p=.000), sex($r^2$ change= 0.066, p= .000), the length of residence($r^2$ change = 0.059, p = .000), the source of pocket money($r^2$ change=0.036, p= .000), age ($r^2$ change=0.018, p=.000). These variables showed a positive correlation with health promotion lifestyle profiles of the Korean elderly in Japan. These variables explained 36.7% of the variance of Health Promotion Lifestyle Profiles. On the basis of the above findings, Health Promotion Lifestyle Profiles programs for Korean elderly in Japan needs be to developed with Japanese social-culture perspectives and needs to develop an intervention method to improve Health Promotion Lifestyle Profiles. It is also suggested that further research is required.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.936-944
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• 2019

Submarines, which have been called an invisible force, are strategic underwater weapon systems that perform missions such as anti-surface warfare, anti-submarine warfare, and high payoff target strikes with the advantage of underwater covertness. A submarine should be able to withstand the hydrostatic pressure of the deep sea. In this respect, the submarine pressure hull, as the main structural system to resist the external pressure corresponding to the submerged depth, should ensure the survivability from hazards and threats such as leakage, fires, shock, explosion, etc. To do this, the initial scantling of the submarine pressure hull must be calculated appropriately in the concept design phase. The shape of the aft transition ring varies according to its connection with the submarine aft end conical structure, pressure hull cylindrical part, and non-pressure hull of the submarine; the design of the aft transition ring should not only take into account stress flow and connectivity but also the cost increase due to the increased man-hours of its complex geometry. Therefore, trade-off studies based on the four different shapes of the aft transition ring are carried out considering both the review of the structural strength through nonlinear finite element analysis (FEA) and economic feasibility by reviewing the estimations of the manufacturing working days and material costs. Finally, the most rational structural aft transition ring shape for a submarine amongst four reviewed types was proposed.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.747-754
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• 2021

Purpose: Seismic safety evaluation of a curved bridge must be performed since the curved bridges exhibit the complex behavior rather than the straight bridges, due to geometrical characteristics. In order to conduct the probabilistic seismic assessment of the curved bridge, Seismic fragility evaluation was performed using the uncertainty of the steel material properties of a curved bridge girde, in this study. Method: The finite element (FE) model using ABAQUS platform of the curved bridge girder was constructed, and the statistical parameters of steel materials presented in previous studies were used. 100 steel material models were sampled using the Latin Hypercube Sampling method. As an input ground motion in this study, seismic fragility evaluation was performed by the normalized scale of the Gyeongju earthquake to 0.2g, 0.5g, 0.8g, 1.2g, and 1.5g. Result: As a result of the seismic fragility evaluation of the curved girder, it was found that there was no failure up to 0.03g corresponding to the limit state of allowable stress design, but the failure was started from 0.11g associated with using limit state design. Conclusion: In this study, seismic fragility evaluation was performed considering steel materials uncertainties. Further it must be considered the seismic fragility of the curved bridge using both the uncertainties of input motions and material properties.

• International Journal of High-Rise Buildings
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• v.10 no.4
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• pp.335-344
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• 2021

In structural engineering practice, understanding the performance of composite columns under extreme loading conditions such as high-rise bulding, long span and heavy loads is essential to accuratly predicting of material responses under severe loads such as fires or earthquakes. Hitherto, the combined effect of partial axial loads and subsequent elevated temperatures on the performance of hollow steel column filled fly ash concrete have not been widely investigated. Comprehensive test was carried out to investigate the effect of elevated temperatures on partial axially loaded square hollow steel column filled fly ash concrete as reported in this paper. Four batches of hollow steel column filled fly ash concrete ( 30 percent replacement of fly ash), (HySC) and normal concrete (CFHS) were subjected to four different load levels, n_f of 20%, 30%, 40% and 50% based on ultimate column strength. Subsequently, all batches of the partially damage composite columns were exposed to transient elevated temperature up to 250℃, 450℃ and 650℃ for one hour. The overall stress - strain relationship for both types of composited columns with different concrete fillers were presented for each different partial load levels and elevated temperature exposure. Results show that CFHS column has better performance than HySC at ambient temperature with 1.03 relative difference. However, the residual ultimate compressive strength of HySC subjected to partial axial load and elevated temperature exposure present an improvement compared to CFHS column with percentage difference in range 1.9% to 18.3%. Most of HySC and CFHS column specimens failed due to local buckling at the top and middle section of the column caused by concrete crushing. The columns failed due to global buckling after prolong compression load. After the compression load was lengthened, the columns were found to fail due to global buckling except for HySC02.

• The Journal of Korean Academy of Sensory Integration
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• v.16 no.2
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• pp.36-49
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• 2018

Objective : The purpose of this study was to examine the validity and reliability of the Korean version of Life Balance Inventory (K-LBI) and to present the relationship between life balance and sensory processing. Methods : K-LBI was constructed through forward and backward translation. Convergent validity, internal consistency, and test-retest reliability were tested for college students. To verify convergent validity, correlation analyses between K-LBI and Korean version of Perceived Stress Scale, Korean version of Satisfaction With Life Scale, and Adult Self Report-Achenbach system of empirically based assessment were performed. Split-half reliability and test-retest reliability were also obtained for reliability verification. We performed the correlation analysis between K-LBI and Korean version of Adolescent/Adult Sensory Profile. Results : A significant correlation was found between K-LBI and the scales for convergent validity. A favorable split-half reliability and test-retest reliability were calculated. The positive correlations were found between relationship life balance and sensory sensitivity/sensation avoiding quadrants. The negative correlation was found between challenges life balance and low registration. Conclusion : This study shows that K-LBI is a valid and reliable tool in Korea. It also provides an in-depth understanding of the relationship between life balance and sensory processing.