• Korean Chemical Engineering Research
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• 제61권3호
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• pp.394-400
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• 2023

In this study, the tuning phenomena, gas storage capacity, and thermal expansion behaviors of binary (cyclopentylamine + CH₄) and (cyclopropylamine + CH₄) clathrate hydrates were investigated for the potential applications of clathrate hydrates to gas storage. To understand the tuning behaviors of binary (cyclopentylamine + CH₄) and (cyclopropylamine + CH₄) clathrate hydrates, ¹³C solid-state NMR spectroscopy was used, and the results confirmed that maximum tuning factors for the binary (cyclopentylamine + CH₄) and (cyclopropylamine + CH₄) clathrate hydrates were achieved at 0.5 mol% and 1.0 mol% of guest concentration, respectively. The gas storage capacity of binary (cyclopentylamine + CH₄) and (cyclopropylamine + CH₄) clathrate hydrates were also checked, and the results showed the CH₄ capacity of our hydrate systems was superior to that of binary (tetrahydrofuran + CH₄) and (cyclopentane + CH₄) clathrate hydrates. The synchrotron diffraction patterns of these hydrates collected at 100, 150, 200, and 250 K confirmed the formation of a cubic Fd-3m hydrate. In addition, the lattice constant of clathrate hydrates with cyclopentylamine and methane were larger than that with cyclopropylamine and methane due to the effects of molecular size and shape.

• The Korean Journal of Franchise Management
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• 제3권1호
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• pp.46-72
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• 2012

Currently, the service industry share in domestic industry is increasing. Especially the size and marketability of the food service industry, which satisfies with basic human desire, is growing significantly. In this food industry, the coffee industry is recognized as a different area from the traditional food industry. The age of instant coffee at low price has gone. Today, more and more customers want to drink more delicious coffee and coffee that is good to their bodies. Especially as individualism has been rambling, more and more people enjoy individualism and want their personal space. This is why coffee speciality stores have been universalized. Also, as coffee speciality stores have been generalized, their own service quality is necessary and they should satisfy and affirm their loyalty to the customers in line with the enhancement of service quality. The purpose of this research is understanding of the impact of coffee specialty shop's service quality on affective commitment and repurchase intentions. The results of an empirical study in this research are as follows: First, compassion among the execution factors of coffee specialty shop's quality has a positive effect on both of affective commitment. But typicality and reactivity don't. Second, affective commitment have a positive effect on repurchase intentions. With a base of the above research result, we should comprehend that another service quality factor exists compared to other dining-out industry and establish marketing strategies in order to contribute to enhance repurchase intentions for the customers.

• Journal of Korean Society of Industrial and Systems Engineering
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• 제46권1호
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• pp.84-90
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• 2023

ASL estimation of public building is based on how appropriate the maximum age of the asset is derived based on the age record of the asset in the statistical data owned by public institutions. This is because we get a 'constrained' ASL by that number. And it is especially true because other studies have assumed that the building is an Iowa curve R3. Also, in this study, the survival rate is 1% as the threshold value at which the survival curve and the predictable life curve almost coincide. Rather than a theoretical basis, in the national statistical survey, the value of residual assets was recognized from the net value of 10% of the acquisition value when the average service life has elapsed, and 1% when doubling the average service life has elapsed. It is based on the setting mentioned above. The biggest constraint in fitting statistical data to the Iowa curve is that the maximum ASL is selected at R3 150%, and the 'constrained' ASL is calculated by the proportional expression on the assumption that the Iowa curve is followed. In like manner constraints were considered. First, the R3 disposal curve for the RCC(reinforced cement concrete) building was prepared according to the discarding method in the 2000 work, and it was jointly worked on with the National Statistical Office to secure the maximum amount of vintage data, but the lacking of sample size must be acknowledged. Even after that, the National Statistical Office and the Bank of Korea have been working on estimating the Iowa curve for each asset class in the I-O table. Another limitation is that the asset classification uses the broad classification of buildings as a subcategory. Second, if there were such assets with a lifespan of 115 years that were acquired in 1905 and disposed of in 2020, these discarded data would be omitted from this ASL calculation. Third, it is difficult to estimate the correct Iowa curve based on the stub-curve even if there is disposal data because Korea has a relatively shorter construction history, accumulated economic wealth since the 1980's. In other words, "constrained" ASL is an under-estimation of its ASL. Considering the fact that Korea was an economically developing country in the past and during rapid economic development, environmental factors such as asset accumulation and economic ability should be considered. Korea has a short period of accumulation of economic wealth, and the history of 'proper' architectures faithful to building regulations and principles is short and as a result, buildings 'not built properly' and 'proper' architectures are mixed. In this study, ASL of RCC public building was estimated at 70 years.

• The Journal of Korean Society for School & Community Health Education
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• 제24권1호
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• pp.1-15
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• 2023

Objectives: The purpose of this study was to identify the major influencing factors of breast cancer death and to suggest policy measures to promote the health of breast cancer patients. Methods: The method of this study performed statistical analysis by applying weights to 2,300 cases of breast cancer registration statistics in Korea collected in 2018 due to the relatively small number of mortality data compared to survival. Statistical processing of the collected data was analyzed using SPSS 26.0. Results: The epidemiologic characteristics of death in breast cancer patients were 31.8% in those aged 70 years or older, and the mortality rate was 5.25 times higher in patients aged 70 years or older than those aged 39 years or younger. The anatomical site code was 36.4% in C50.4~C50.6, and the mortality rate was 1.82 times higher in C50.4~C50.6 than in C50.0~C50.1. The tumor size was 40.4% and larger than 4cm, and the mortality rate was 4.53 times higher in tumors larger than 4cm than those smaller than 1cm. The degree of differentiation was 13.9% in the poorly differentiated group, and the mortality rate was 4.38 times higher in the poorly differentiated group than in the highly differentiated group. In the hormone receptor test, non-triple negative cases were 59.6%, and the mortality rate was 0.57 times lower in non-triple negative cases than in triple negative cases. As for lymph node involvement, the presence or absence of lymph node involvement was 78.8%, and the mortality rate with lymph node involvement was 1.36 times higher than that without lymph node involvement. The survival period of 13 to 24 months was the highest at 26.5%, and the average survival period was 25.68 months (±14.830). Conclusion: A policy to advance the timing of national health examinations for early detection of breast cancer is necessary. In addition, a bill for the mandatory placement of health educators in medical institutions for patients with special diseases such as breast cancer should be prepared.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제30권2D호
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• pp.153-161
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• 2010

The city planning of a local government is a continuous process that does not end with the creation of a plan but proceeds through decision-making, monitoring and evaluation phases. As a new city planning is changed and confirmed, there is a chance to construct a large scale road that is connected with an under constructed road. In this case, the expansion of the width and length of road, the addition of bridges or tunnels, and the change of the size and location of interchanges lead to many changes on road design and construction. In the past, the consignment contracts for a road construction have been made in limited numbers and for limited civil works. Now, it is growing in numbers and is making for large scale multi-works. However, the standard process and guidelines for the consignment contracts have not been suggested yet, so there is difficulty in performing the consigned road construction effectively. In this paper, the important factors for the consignment contracts are determined by construction document reviews and expert interviews. Based on these results, a standard process for the consigned contracts and a guideline for agreeing on construction cost are suggested. The costs that should be paid by a consignor are also defined.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제28권4B호
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• pp.383-392
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• 2008

It is not always easy to estimate the parameters in hydrologic models due to insufficient hydrologic data when hydraulic structures are designed or water resources plan are established. Therefore, uncertainty analysis are inevitably needed to examine reliability for the estimated results. With regard to this point, this study applies a Bayesian Markov Chain Monte Carlo scheme to the NWS-PC rainfall-runoff model that has been widely used, and a case study is performed in Soyang Dam watershed in Korea. The NWS-PC model is calibrated against observed daily runoff, and thirteen parameters in the model are optimized as well as posterior distributions associated with each parameter are derived. The Bayesian Markov Chain Monte Carlo shows a improved result in terms of statistical performance measures and graphical examination. The patterns of runoff can be influenced by various factors and the Bayesian approaches are capable of translating the uncertainties into parameter uncertainties. One could provide against an unexpected runoff event by utilizing information driven by Bayesian methods. Therefore, the rainfall-runoff analysis coupled with the uncertainty analysis can give us an insight in evaluating flood risk and dam size in a reasonable way.

• Journal of Nutrition and Health
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• 제56권3호
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• pp.288-299
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• 2023

Purpose: This study aimed to assess the weight fluctuations in college students during the coronavirus disease 2019 (COVID-19) pandemic and identify lifestyle and dietary changes related to weight gain. Methods: An online survey was conducted on 270 college students from September 22 to October 26, 2021. A logistic regression analysis was performed to analyze the relationship of weight gain with the general characteristics, lifestyle, and dietary changes of the students. Results: Among the respondents, 42.9% of men and 44.7% of women reported weight gain. The main reasons given for weight gain were reduced activities due to restrictions during lockdown and diet changes, mainly relating to delivered or fast foods. Among the general characteristics and lifestyle factors poor perceived health (odds ratio [OR], 3.97, 95% confidence interval [CI], 1.98-7.96) and being underweight (OR, 0.19, 95% CI, 0.05-0.83) were significantly associated with weight gain. With respect to the diet, increased frequency of eating breakfasts (OR, 4.44, 95% CI, 1.76-11.21), decreased frequency of eating snacks (OR, 0.35, 95% CI, 0.16-0.77), decreased frequency of fruit intake (OR, 3.0, 95% CI, 1.32-6.80), increased frequency of carbonated and sweetened beverage intake (OR, 2.74, 95% CI, 1.26-5.99) and increased frequency of fast food consumption (OR, 2.32, 95% CI, 1.14-4.70) were significantly associated with weight gain. Conclusion: The COVID-19 pandemic affected weight gain and caused lifestyle and dietary changes. Specific health and nutrition management plans should be prepared for handling future epidemics of infectious diseases based on the results of surveys conducted on larger sample size.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제26권3A호
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• pp.513-521
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• 2006

Many studies have been conducted on the high tension bolt friction connection in the view of the field practice. Those effort, however, unfortunately have not been appropriately applied in the design specifications. Recently, particularly for steel bridges, rationalization of design takes greater attention from designers and hence, demand on rationalization of high tension connection becomes more significant. The purpose of this study is to suggest direction for the rationalization of high tension bolt connection and to also provide fundamental information for the improvement of the design specifications. In order to accomplish the purposes, the design specifications in Korea was analyzed and compared with other specification from abroad, and was studied one of the most important factors including slip coefficient, and the specifications on the size of bolt holes. The effect of over-sized bolt hole and the reduction of axial force on bolt was evaluated through the experimental studies on the slippage of the high tension bolt connections. Other research topics included herein includes the difference of slip coefficients, the effect of over-sized bolt holes and the gap distance of members, and the application of filler plate and corrosion protected bolts. From the research results, it is known that the specifications in Korea apply a constant slip coefficient with respect to the contacted surface conditions while various coefficients are available depending on the contacted surface conditions. Therefore, it is recommended that the specifications in Korea also develop and detail the slip coefficient which can appropriately take account of the variation of the contacted surface conditions. It is also suggested that the limitation abroad on the over-sized bolt hole may be applied for enhancing the effectiveness of construction.

• Fisheries and Aquatic Sciences
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• 제26권9호
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• pp.558-568
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• 2023

Vibrio vulnificus is an aquatic bacterium causing septicemia and wound infection in humans. To understand this pathogen at the genomic level, it was performed whole genome sequencing of a cefoxitin-resistant strain, V. vulnificus 1908-10 possessing virulence-related genes (vvhA, viuB, and vcgC) isolated from Gadeok island coastal seawater in South Korea. The genome of V. vulnificus 1908-10 consisted of two circular contigs and no plasmid. The total genome size was estimated to be 5,018,425 bp with a guanine-cytosine (GC) content of 46.9%. We found 119 tRNA and 34 rRNA genes respectively in the genome, along with 4,352 predicted protein sequences. Virulence factor (VF) analysis further revealed that V. vulnificus 1908-10 possess various virulence genes in classes of adherence, antiphagocytosis, chemotaxis and motility, iron uptake, quorum sensing, secretion system, and toxin. In the comparison of the presence/absence of virulence genes, V. vulnificus 1908-10 had fur, hlyU, luxS, ompU, pilA, pilF, rtxA, rtxC, and vvhA. Of the 30 V. vulnificus comparative strains, 80% of the C-genotype strains have all of these genes, whereas 40% of the E-genotype strains have all of them. In particular, pilA were identified in 80% of the C-type strains and 40% of the E-type strains, showing more difference than other genes. Therefore, V. vulnificus 1908-10 had similar VF characteristics to those of type C strains. Multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin of V. vulnificus 1908-10 contained 8 A-type repeats (GXXGXXXXXG), 25 B.1-type repeats (TXVGXGXX), 18 B2-type repeats (GGXGXDXXX), and 7 C-type repeats (GGXGXDXXX). The National Center for Biotechnology Information (NCBI) Basic Local Alignment Search Tool (BLAST) showed that the RtxA protein of V. vulnificus 1908-10 had the effector domain in the order of cross-liking domain (ACD)-C58_PaToxP-like domain- α/β hydrolase-C58_PaToxP-like domain.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• 제28권4호
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• pp.143-157
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• 2023

This study confirmed the characteristics of macrobenthic community due to anthropogenic environmental changes in the Boryeong Jugyo tidal flat, where the habitat of manila clam (Ruditapes philippinarum) and mud shrimp (Upogebia major) is separated. The total number of occurring species was 55 during the study period with an average habitat density of 338 ind./m² and a biomass of 212.2 gWWt/m². The number of occuring species increased from 27 species at the upper flat to 37 species at the lower flat, and the dominant species differed by tide levels (Upper: Leonnates persica, Middle: Heteromastus filiformis, Lower: R. philippinarum). The macro-benthic community sturctures of the top 10 species using cluster analysis and nMDS were divided into two groups, focusing on Manila clam culture farm of lower flats and middle flats with high habitat density, reflecting the influence of specific species. The sediment composition of the U. major habitat space fluctuated highly, but it was maintained annually, and the sorting coefficient was 2.1 𝜑, and the proportion of the same particle size was increased. In particular, because the middle flat has a dense anthropogenic impact, a dominant species, H. filiformis dominated and revealed a relationship with the density of burrow holes of U. major, which is considered to be a biological interaction between these two macrofauna in this tidal flat.