• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.46.1-46.12
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• 2023

Background: As unpredictable work schedule (UWS) has increased worldwide, various studies have been conducted on the resulting health effects on workers. However, research on the effect of UWS on workers' well-being in Korea is still insufficient. This study aimed to investigate the relationship between UWS and work-family conflict (WFC) using 6th Korean Working Conditions Survey (KWCS). Methods: Both UWS and WFC were measured using self-reported questionnaires, using data from the 6th KWCS conducted between 2020 and 2021, including 31,859 participants. UWS was measured by questions regarding the frequency of changes in work schedules and limited advanced notice. WFC was measured by questions regarding work to family and family to work conflicts. Logistic regression analysis was conducted to investigate the association between UWS and WFC. Results: The prevalence of UWS was higher among men, those under 40 years old, service and sales workers and blue-collar workers, and those with higher salaries. Workplace size also influenced UWS prevalence, with smaller workplaces (less than 50 employees) showing a higher prevalence. The odds ratio (OR) for WFC was significantly higher in workers with UWS compared to workers without UWS after adjusting for gender, age, marital status, occupation, salary, education, weekly working hours, shift work, company size, and having a child under the age of 18 years, employment status (OR: 3.71; 95% confidence interval: 3.23-4.25). Conclusions: The analysis of nationwide data revealed that UWS interferes with workers' performance of family roles, which can lead to WFC. Our findings suggest that it is crucial to implement policies to address unfair work schedule management, promoting a healthier work-life balance and fostering a conducive environment for family responsibilities.

• Physical Therapy Korea
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• v.30 no.3
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• pp.202-210
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• 2023

Background: The elderly population is increasing rapidly worldwide. Muscle mass, usual walking speed (UWS), knee extension strength (KES), hand grip strength (HGS), peak expiratory flow (PEF), and depression is used for sarcopenia diagnosis. All four of these factors (KES, HGS, PEF, and depression) correlated with UWS and also to muscle mass. But, many studies have suggested that no correlation exists between muscle mass and UWS. Objects: This study aimed: 1) to investigate whether muscle mass reduction affected UWS, as mediated by KES, HGS, PEF and depression, and 2) to explored whether significant changes in these mediators varied by the body segment in which muscle mass evaluated in elderly female aged 65-80 years. Methods: A total of 100 female aged 65-80 years were surveyed. Muscle mass was measured by body segment (upper and lower segment), and KES, HGS, PEF, depression, and UWS were also assessed. Median analyses were progressed in IBM SPSS software (ver. 23.0, IBM Co.) using a downloaded INDIRECT macro. Results: The direct effect of the KES and PEF were significant, and the indirect effect of KES and PEF were not significant. Thus, KES and PEF served as full mediators of the effect of muscle mass on UWS. Regardless of bodily region, KES and PEF combined with muscle mass were significant mediators of UWS, with similar indirect effect sizes. Conclusion: KES and PEF are the only mediators regardless of body part. Therefore, mediating the KES and PEF may prevent sarcopenia progression in elderly female. Also, sarcopenia can be readily assessed by evaluating either the upper or lower body; it is not necessary to measure total muscle mass.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.587-602
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• 2023

Due to climate change, population growth, and economic development, the demand for water in the urban water system (UWS) and the energy required for water use constantly increase. Therefore, beyond the traditional method of considering only the water sector, the Nexus approach, which considers synergies and trade-offs between the water and energy sectors, has begun to draw attention. In previous researches, the Nexus methodology was used to demonstrate that the UWS is an energy-intensive system, analyze the water-energy efficiency relationship surrogated by energy intensity, and identify climate (long-term climate change, drought, type), geographic characteristics (topography, flat ratio, location), system characteristics (total supply water amount, population density, pipeline length), and operational management level (water network pressure, leakage rate, water saving) effects on the UWS. Through this, it was possible to suggest the direction of policies and institutions to UWS managers. However, there was a limit to establishing and implementing specific action plans. This study built the energy intensity matrix of the UWS, quantified the impact of city conditions, external influences, and operational management levels on the UWS using the water-energy Nexus model, and introduced water-energy efficiency criteria. With this, UWS managers will be able to derive strategies and action plans for efficient operation management of the UWS and evaluate suitability and validity after implementation.

• Journal of Veterinary Clinics
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• v.26 no.5
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• pp.445-449
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• 2009

For human organ transplantations, histidine-tryptophan-ketoglutarate solution (HTKS) and University of Wisconsin solution (UWS) have been shown to engender similar outcomes as gold standard cold preservation solutions ($4^{\circ}C$). To select the effective preservation solution for cold storage of kidney xenografts in miniature pig, which could be a potential source animal of bio-organs, this study compared early histopathological outcomes of cold preservation injury using HTKS and UWS. Twelve miniature pigs weighing 25.6 to 34.7 kg were divided into two groups (n = 6 per group), UWS group and HTKS group. The kidneys in each group were harvested, cold flushed, and preserved for 0, 24, 48, and 72 hrs at $4^{\circ}C$ with UWS or HTKS, respectively. Histolopathological examinations were assessed on kidney biopsy specimens, taken after each cold storage. The degree of renal injury was scored using 5 different criteria (pyknotic nuclei, disruption of cytoplasm, detachment of epithelium, loss of microvilli, tubular necrosis and loss of glomerular tufts) of the cellular components of the tissue. The degree of kidney damage was increased with prolonged cold ischemia time. UWS and HTKS have at least similar efficacy in kidney preservation within 24 hrs cold preservation time. However, in HTKS group cold-induced injury started to be observed more than in UWS group after 48 hrs of cold storage. In conclusion, UWS and HTKS were equally effective for cold preservation of miniature pig kidney in early preservation times; however, UWS may be more effective at longer preservation times as compared to HTKS.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1066-1075
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• 1996

To compare the efficacy of cardiac preservation, we examined purine metabolites during 24 hours of cold storage($0^{\circ}C$) of the Korean ongrel dog hearts after using three different types of cardioplegic solutions. The hypothermic arrest with total cardiopulmonAry bypass method was employed in 51. Thomas solution(575) and blood cardioplegic solution(BCPS) preservation cases. Specimens were analyzed for levels of adenine nucleotides and their precursors by high performance liquid chromatography. The ATP content in the UW(University of Wisconsin) solution group tends to be higher than that of the combined hypothermic arrest group(575 and BCPS groups) after 2,4,8, and 12 hours of preservation respectively, but there were no significant differences between 575 and BCPS groups. The ADP contents in the UWS and BCPS groups were higher than that of the 575 group at 4,8, 12, and 24 hours, but the difference was not statistically significant between UWS and BCPS groups. The AMP contents did not change significantly in the three groups. The adenosine, Inosine, and hypoxanthine concentrations increased progressively, but the lev l of xanthine was very low in the three groups.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.467-472
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• 2004

Eight primiparous Holstein cows, in late lactation (255$\pm$10 days in milk) and yielding 10.3$\pm$1.3 kg/d of 4% fat corrected milk (FCM) were allocated into two groups randomly. Two diets containing 30% wheat straw either untreated (UWS) or treated with Pleurotus ostreatus (FTWS) were offered as total mixed ration (TMR). In vivo digestibility of the diets was determined, using acid insoluble ash as a marker. Daily milk production was recorded and milk samples were collected and analysed. Diet FTWS resulted in significantly (p<0.05) higher dry matter intake (DMI) (12.2$\pm$0.86 vs. 10.6$\pm$1.3), DM digestibility (58.8 vs. 52.3) and milk yield (9 vs. 7.5 kg). Milk fat contents were 34.2 and 35.6 g/liter that did not differ between cows fed treated or untreated straw. However, the concentrations of lactose, solid non fat, total solids and milk protein for diets UWS and FTWS were 57.3 and 54.9, 98.9 and 93.2, 134.5 and 127.4, 35.7 and 32.3 g/l, respectively, which differed significantly (p<0.05). The average body weights gain (BWG) for UWS and FTWS were 272 and 743 g/d, respectively (p<0.05). The FCM yield per kg of DMI was similar (0.68 and 0.67 liter) for the two groups, but BWG/kgDMI was higher in the FTWS diet.

• Smart Structures and Systems
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• v.18 no.5
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• pp.1005-1028
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• 2016

Two novel semi-active control methods for a seismically excited nonlinear benchmark building equipped with magnetorheological dampers are presented and evaluated in this paper. While a primary controller is designed to estimate the optimal control force of a magnetorheological (MR) damper, the required voltage input for the damper to produce such desired control force is achieved using two different methods. The first technique uses an optimal compact Takagi-Sugeno-Kang (TSK) fuzzy inverse model of MR damper to predict the required voltage to actuate the MR dampers (TSKFInv). The other voltage regulator introduced here works based on the maximum and minimum capacities of MR damper at each time-step (MaxMin). Both semi-active algorithms developed here, use acceleration feedback only. The results demonstrate that both TSKFInv and MaxMin algorithms are quite effective in seismic response reduction for wide range of motions from moderate to severe seismic events, compared with the passive systems and performs better than original and Modified clipped optimal controller systems, known as COC and MCOC.

• Perspectives in Nursing Science
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• v.4 no.1
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• pp.19-25
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• 2007

Systems and processes to provide clinical education to students of nursing have been established between universities and health facilities in all countries where nurse education is tertiary based. However, systems and processes to link nurse researchers based in universities to their clinical colleagues are less well developed. When collaborations are established they are frequently based on personal networks, and while the rhetoric of the organizations encourages these collaborations, they are largely unrecognised by senior administrators in health facilities. The research is frequently "invisible" and the clinician researchers usually do not have access to appropriate infrastructure and other resources that are required to support large projects that have the potential to change practice across organisations. This situation influences the focus and scope of nursing research and limits opportunities for clinicians to be engaged in the generation of professional knowledge. The University of Western Sydney (UWS) has taken a strategic approach to the development of collaborations for research and has linked with health services in Western Sydney to establish and maintain research centres and adjunct appointments. The partner organisations jointly fund the infrastructure of the centres which include a Professor, research assistant position(s) and administrative staff. Five Professors of Nursing have been appointed to positions in one of three nursing research centres. This paper describes the approach established by the School of Nursing at UWS to build collaborations with clinical areas to promote research. This approach could be adopted or adapted by other facilities.

• Journal of ILASS-Korea
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• v.25 no.4
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• pp.196-203
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• 2020

Nowadays, urea SCR technology is considered as the most effective NOx reduction technology of diesel engine. However, low NOx conversion efficiency under low temperature conditions is one of its problems to be solved. This is because injection of UWS (Urea Water Solution) is impossible under such a low temperature condition due to the problem of insufficient of urea decomposition and urea deposits. In several previous studies, it has been reported that appropriate control of the amount of ammonia adsorbed on SCR catalyst can improve the NOx conversion efficiency under low temperature conditions. In this study, we tried to find out how much the NOx conversion efficiency increases with respect to the amount of ammonia adsorbed on the catalyst, and what the temperature conditions that the ammonia slip occurs. This study shows the results of 8 times repeated WHTC test with a diesel engine, in which UWS was injected with NH3/NOx mole ratio of '1'. Through this study, it was found that 13% of the NOx conversion efficiency of WHTC increased while the θ (ammonia adsorption rate) increased from "0%" to "22%". In addition, it is found that in cases of high θ value, the significant improvement of NOx conversion efficiency at low temperatures presented during the beginning period of WHTC and at high temperature and transient conditions presented during last part of WHTC test. The NH3 slip occurring condition was 250℃ of catalyst temperature and 10% of θ, and the amount of NH3 slip increased as the temperature and θ are increased.

• Steel and Composite Structures
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• v.39 no.5
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• pp.529-542
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• 2021

Shear connectors are required to build composite (concrete and steel) beams. They are placed at the interface of concrete and steel to transfer shear and normal forces between two structural components. Such composite beams are sensitive to provide structural integrity when exposed to fire as they loss strength, stiffness, and ductility at elevated temperature. The present study is designed to investigate the shear resistance and the failure modes of the headed stud shear connectors at fire exposure and post-fire exposure. The study includes ordinary concrete and concrete with carbon nanotubes (CNTs) to build composite (concrete-steel) beams with structural steel. Experimental push tests were conducted on composite beams at ambient and elevated temperatures, such as 200, 400 & 600℃. Moreover, push tests were performed on the composite beams after being exposed to 200, 400 & 600℃. Push test results illustrated the reduction of ultimate shear capacity and stiffness of headed stud shear connectors as the temperature increased. Although similar values of ultimate shear were obtained for the headed stud connectors in both ordinary and CNT concrete, the CNT modified concrete reduced the concrete spalling and cracking compared to ordinary concrete and was observed to be effective at temperatures greater than 400℃. All specimens showed a lower shear resistance at fire exposures compared to the corresponding post-fire exposures. Moreover, numerical simulation by Finite Element (FE) analyses were carried out at ambient temperature and at fire conditions. The FE analysis results show a good agreement with the experimental results. In the experimental studies, failure of all specimens occurred due to shear failure of headed stud, which was later validated by FE analyses using ABAQUS.