• Journal of Korean Society of Water and Wastewater
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• v.31 no.2
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• pp.177-186
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• 2017

This study concerned the analysis on the efficiency of the conversion of water tank type supply system to direct water supply system to examine the feasibility of the conversion, as well as the calculation of optimal conversion range that enables the supply of safe, high-quality water at stable pressure in accordance with the standards of water supply facility. The results of this research showed that when converting water supply system from water tank type supply system to direct water supply system, more nodal points could be properly converted and more reduction of electricity usage was expected in case water pressure rather than residence time was fixed. This means that higher efficacy can be obtained by fixing water pressure when converting water supply system. However, since the number of the locations that received on-spot inspection was small and the electricity usage measured was not exclusively by water supply facility, it is difficult to judge that such reduction of electricity usage accurately represents reduced electricity usage by water supply facility alone. therefore, after having secured on-spot information about a larger number of locations in apartment complexes that have converted water supply system, and utilizing information about electricity usage exclusively by water supply facility, the proposed method of this research could be applied to accurately deducing expected reduction of electricity usage by water supply facilities of various other apartment complexes. It is also considered possible to deduce an effective operation method of water supply system by finding out an area that shows low pressure or low residual chlorine concentration in the optimal conversion range of water supply, followed by estimating the proper location of pumping station or the proper chlorine dosage at the power purification plant that supply water to the target area.

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.339-350
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• 2018

Purpose: The purpose of this study is to propose useful suggestions by analyzing the impact of SNS quality and the pressure which comes from SNS usage objectives on SNS discontinuance intention. Methods: We developed a SNS user's discontinuance intention model in terms of SNS quality and pressure of SNS usage. Survey data of SNS users was analyzed using multi-regression analysis for testing hypotheses. Results: We found that information quality plays an important role in lowering the SNS discontinuance intention. In addition, it was founded that pressure of social networking and information processing are positively related with the SNS discontinuance intention. Conclusion: We expect that this research can provide theoretical and practical implications. As for theoretical, this study can suggest the insight on conceptualization of SNS fatigue in the further study. Regarding practical implication, service providers can make their service strategies based on understanding our analysis.

• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.175-183
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• 2017

Codon usage bias (CUB) is a unique property of genomes and has contributed to the better understanding of the molecular features and the evolution processes of particular gene. In this study, genetic indices associated with CUB, including relative synonymous codon usage and effective numbers of codons, as well as the nucleotide composition, were investigated in the Clonorchis sinensis tyrosinase genes and their platyhelminth orthologs, which play an important role in the eggshell formation. The relative synonymous codon usage patterns substantially differed among tyrosinase genes examined. In a neutrality analysis, the correlation between $GC_{12}$ and $GC_3$ was statistically significant, and the regression line had a relatively gradual slope (0.218). NC-plot, i.e., $GC_3$ vs effective number of codons (ENC), showed that most of the tyrosinase genes were below the expected curve. The codon adaptation index (CAI) values of the platyhelminth tyrosinases had a narrow distribution between 0.685/0.714 and 0.797/0.837, and were negatively correlated with their ENC. Taken together, these results suggested that CUB in the tyrosinase genes seemed to be basically governed by selection pressures rather than mutational bias, although the latter factor provided an additional force in shaping CUB of the C. sinensis and Opisthorchis viverrini genes. It was also apparent that the equilibrium point between selection pressure and mutational bias is much more inclined to selection pressure in highly expressed C. sinensis genes, than in poorly expressed genes.

• Journal of Information Technology Applications and Management
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• v.25 no.1
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• pp.105-124
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• 2018

The usage level of SMEs' win-win payment system is still lower than originally expected. In order to find the answer, we studied SMEs' usage performance of win-win payment system and analyzed the influencing factors of SMEs' usage level of win-win payment system. This study found that the more SMEs utilize win-win payment system, the higher they achieve the desired performance in finance, customer, process, learning and growth perspective. And this study found that usage level of win-win payment system is high in order of large corporations' pressure, government policy, and SMEs' readiness. This study is expected to improve win-win growth by increasing usage level of win-win payment system between large corporations and SMEs, while establishing desirable ecosystems.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.2
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• pp.185-196
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• 2020

Low-pressure sodium lamps, high-pressure sodium lamps and fluorescent lamps etc are mainly used tunnel lighting in Rep. of Korea. Power rates for tunnel lighting are known to account for the highest percentage in the tunnel maintenance costs. Therefore, tunnel lights are being replaced by LED that have advantages such as low power consumption and longevity. To analysis effect of replacement low pressure sodium lamp with LED, illumination and monthly power usage for a year are investigated for 8 tunnels. Power usage for tunnel lighting is decreased by 26.1% to 59.6%, and illumination is increased by 34.1% to 293% replacing low pressure sodium lamp with LED.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.4
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• pp.211-220
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• 2021

Low-pressure sodium lamps, high-pressure sodium lamps, and fluorescent lamps are mainly used for tunnel lighting in Rep. of Korea, which accounts for the highest percentage in the tunnel maintenance costs. Therefore, tunnel lights are being replaced by LED lamp that have advantages with respect to low power consumption and sustainability. To analyze the effect of replacement high pressure sodium lamp with LED lamp, illumination and monthly power usage per year have been investigated for 10 tunnels. The usage of LED lamp results in illumination improvement from 27.9% to 490% and power saving around average 47.1%.

• Journal of Plant Biotechnology
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• v.49 no.1
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• pp.46-60
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• 2022

The genetic variability and population structure of apple mosaic virus (ApMV) have been studied; however, synonymous codon usage patterns influencing the survival rates and fitness of ApMV have not been reported. Based on phylogenetic analyses of 52 ApMV coat protein (CP) sequences obtained from apple, pear, and hazelnut, ApMV isolates were clustered into two groups. High molecular diversity in GII may indicate their recent expansion. A constant and conserved genomic composition of the CP sequences was inferred from the low codon usage bias. Nucleotide composition and relative synonymous codon usage (RSCU) analysis indicated that the ApMV CP gene is AU-rich, but G- and U-ending codons are favored while coding amino acids. This unequal use of nucleotides together with parity rule 2 and the effective number of codon (ENC) plots indicate that mutation pressure together with natural selection drives codon usage patterns in the CP gene. However, in this combination, selection pressure plays a more crucial role. Based on principal component analysis plots, ApMV seems to have originated from apple trees in Europe. However, according to the relative codon deoptimization index and codon adaptation index (CAI) analyses, ApMV exhibited the greatest fitness to hazelnut. As inferred from the results of the similarity index analysis, hazelnut has a major role in shaping ApMV RSCU patterns, which is consistent with the CAI analysis results. This study contributes to the understanding of plant virus evolution, reveals novel information about ApMV evolutionary fitness, and helps find better ApMV management strategies.

• Journal of Ocean Engineering and Technology
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• v.30 no.3
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• pp.201-207
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• 2016

In this paper, an aluminum pressure vessel (cylinder) for a 200 m water depth is designed and analyzed. Because of their lack of usage in the deep sea, only a few papers about pressure vessels subjected to external pressures have previously been published. Moreover, the high level of imported external-pressure-vessel products limits the academic pursuit. Yet, research on internal pressure vessels is widely available because of their broad usage at onshore. This paper presents the process of basic designing and modelling of pressure vessels using the design rules of American Standard of Mechanical Engineering (ASME) Section VIII Division 1. To promote understanding, finite element analysis (FEA) result of an existing sample cylinder which was not designed by ASME code is compared with the design obtained in this paper. Several methodologies are used for the finite element analysis, including rectangular, cylindrical, and axisymmetric coordinate, to attain an accurate stress result. Same dimensions except the thickness of the cylinder and loading condition of 0.200 MPa was given for the current study. Finally, a rigorous design procedure is added for the bolt and boundary conditions of the cylindrical body and its ends. The obtained stress level satisfies the allowable design stress value specified in the ASME code.

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.683-688
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• 2012

The structural integrity of mechanical components during several transients should be assured in the design stage. This requires a fatigue analysis including thermal and stress analyses. As an example, this study performs a fatigue analysis of the reactor pressure vessel of SMART during arbitrary transients. Using heat transfer coefficients determined based on the operating environments, a transient thermal analysis is performed and the results are applied to a finite element model along with the pressure to calculate the stresses. The total stress intensity range and cumulative fatigue usage factor are investigated to determine the adequacy of the design.

• Nutrition Research and Practice
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• v.6 no.3
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• pp.232-237
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• 2012

This study was done to explore the effect of Korean women's salt usage behavior on their sodium intake and excretion according to aging. Dietary sodium intake and salt usage behavior were analyzed to compare the difference between young and middle-aged women. One hundred fifty six young women and 77 middle-aged women without hypertension or any current medication were recruited. Body mass index, waist hip ratio, blood pressure were measured from each subject. Salt usage behaviors were surveyed with questionnaire, sodium intake with 24-hr recall method, and sodium excretion with spot urine. Middle-aged women were more obese than young women according to body mass index and waist hip ratio. Blood pressure was significantly higher for the middle-aged. Young women consumed more fats and middle-aged women more carbohydrates. Middle-aged women consumed more sodium and potassium, and excreted more sodium. Among questionnaire items, kimchi, soup or pot stew, or salted vegetables were found to be related with high sodium diet. Salted vegetables and salted nuts and potato chips were significantly correlated with young women's high sodium diet, while soy sauce on fried food, kimchi, salted vegetables accounted for middle-aged women's high sodium diet. With these results, we concluded that middle-aged women consumed more carbohydrates, less fat, and more sodium and potassium than young women. Middle-aged women frequently choose kimchi, soup or pot stew, or salted vegetables, and they contribute to high sodium intake. We recommend to choose low-salt kimchi, less soup or pot stew, and more fresh vegetables for lower sodium diet.