• Journal of the Korea Concrete Institute
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• v.19 no.2
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• pp.179-188
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• 2007

Recently, the concern on the receipt of poor ready-mixed concrete in the construction field and the durability of concrete has been increased. Based on the such background, a large number of measuring methods of water content for fresh concrete have been developed and enforced in a developed country. In this study, to investigate practicality for quality control of ready-mixed concrete among various water content measurement techniques, microwave range method, air meter method and capacitance measurement method as measuring methods of water content were selected. Then, it was evaluated estimating performance of water content according to the change of binder types, fine aggregate types, absorption ratio, water content and water-binder ratio in series I and II. Also, it was examined influence on error occurrence of water content according to change of properties of used materials in series III. Finally, based on this study, it was proposed fundamental data to utilize measurement technique of water content to quality control of ready-mixed concrete in construction field.

• Journal of the Korean housing association
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• v.20 no.2
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• pp.59-68
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• 2009

Community centers have been public facilities for the welfare and conveniences for the residents since 1999. Currently, the numbers of community centers meet the demands in quantity, but they do not satisfy the quality service needs for the improved life style of residents and the activation of local community. Therefore, the purposes of this research are to find out the current status, types and characters of facilities for the quality improvement of community centers. As the research methods, 'home pages of community centers', 'gujung backseo' were used, and '40 case studies' were completed. Case studies were done by observation and research on the actual conditions. The case works were done between July- September in 2008. Followings are the results of the study; 1. Area measurements of the community centers are being increased since 2000. 2. Complex facility types of community centers are mainly public administrative facilities (community center)+public administrative facilities of mixed type. 3. There are three architectural types of community centers: horizontal type, vertical type, mixed type. 4. There are three classified entrance types for the community centers. 5. There are twelve classified facility types for the community centers. Community centers are usually mixed with diverse facilities, especially welfare facilities and cultural facilities. Proper community center types which contain the functional characters and varieties of facilities should be developed, and these active centers should be used conveniently by residents, thus, further study is required in this regard.

• Journal of Smart Tourism
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• v.2 no.1
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• pp.21-31
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• 2022

This review paper aims at providing a systematic analysis of articles published in various journals and related to the uses and business applications of big data. The goal is to provide a holistic picture of the place of big data in the tourism industry. The reviewed articles have been selected for the period 2013-2020 and have been classified into 8 broad categories namely business strategy and firm performance; banking and finance; healthcare; hospitality; networks and telecommunications; urbanism and infrastructures; law and legal regulations; and government. While the categories are reflective of components of tourism industries and infrastructures, the meta-analysis is organized around 3 broad themes: preferred research contexts, conceptual developments, and methods used to research big data business applications. Main findings revealed that firm performance and healthcare remain popular contexts of research in the big data realm, but also demonstrated a prominence of qualitative methods over mixed and quantitative methods for the period 2013-2020. Scholars have also investigated topics involving the notions of competitive advantage, supply chain management, smart cities, but also ethics and privacy issues as related to the use of big data.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.6
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• pp.907-917
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• 2000

Although interest in the potential and actual usage of the Internet as a transaction medium is increasing, the market for fashion merchandise on the Internet in Korea has yet to take off. As the Internet environment is expected to bring about a transformation of conventional consumer buying behavior, the purpose of this exploratory research is to investigate the buying behavior of fashion products on the Internet to identify relevant concepts and generate hypotheses for further empirical research. The research methods selected for the study were observation and in-depth interview. Twelve subjects who had purchased fashion products on the Internet were selected and interviewed. Those who could not participate in face-to-face in-depth interviews because of the geographic locations were interviewed on-line. The results are as follows: First, subjects went through the stages of shopping motivation stage, site choice behavior stage, in-site behavior stage, and postpurchase behavior stage. Second, a model was extracted for each shopping stage, and a final model was completed based on comparisons with the participants processes. The information content of each phase was discussed. Finally, each participant was classified using their purchasing process, revealing six possible mixed usage patterns of the Internet marketing system and the traditional marketing system.

• Korean Journal of Occupational Health Nursing
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• v.26 no.2
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• pp.93-104
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• 2017

Purpose: This is a mixed method study to understand the experience regarding the job satisfaction of Physician Assistant (PA) male nurses. Methods: First, factors influencing job satisfaction were analyzed using quantitative approach and job adaptation processes by qualitative research was done through interviews. Finally both of the collected data were comprehensively compared. Results: The factors which had the greatest influence on job satisfaction in the regression analysis were job stress (${\beta}=-.49$, p<.001) and job identity (${\beta}=.46$, p<.001) and the explanatory power explaining these variables was 58% (Adj. $R^2=.58$). The results of qualitative research were categorized using the same four variables with qualitative research variables. Five themes in job satisfaction, three themes in job identity, five themes in job stress and six themes in job value were identified by content analysis. Conclusion: This finding identified that the job stress and job identity were important variables related to job satisfaction. Therefore, the factors influencing job identity have to be strengthened, and a systematic management and interest to develop them are necessary.

• Journal of the korean society of oceanography
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• v.37 no.1
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• pp.45-50
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• 2002

New production (NP) values in well-mixed waters of the Yellow Sea were estimated using two different methods and were compared with each other; one is from the quantum yield model of nitrate uptake and chlorophyll ${\alpha}$-specific light absorption coefficient, and the other is from a traditional $^{15}N$-labelled stable isotope uptake technique. The quantum yields of nitrate uptake were highly variable, ranging from 0.0001 to 0.04 mol $NO_3Ein^{-1}$, and the small values in this study might have resulted from either the partitioning into nitrate uptake of little portions of light energy absorbed by phytoplankton or that phytoplankton may predominantly utilize other N sources (E. G. ammonium and/or urea) than nitrate. The estimates (0.54-8.47 nM $h^{-1}$) of NP from the quantum yield model correlated well ($r^2$=0.67, p<0.1) with those (0.01-4.93 nM $h^{-1}$) obtained using the $^{15}NO_3$ uptake technique. To improve the ability of estimating NP values using this model in the Yellow Sea, more data need to be accumulated in the future over a variety of time and space scales.

• Nuclear Engineering and Technology
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• v.52 no.1
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• pp.178-184
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• 2020

The traditional methods for radiation shield design always only focus on either the structure or the components of the shields rather than both of them at the same time, which largely affects the shielding performance of the facilities, so in this paper, a novel method for designing the structure and components of shields simultaneously is put forward to enhance the shielding ability. The method is developed by using the genetic algorithm (GA) and the MCNP software. In the research, six types of shielding materials with different combinations of elements such as polyethylene (PE), lead (Pb) and Boron compounds are applied to the radiation shield design, and the performance of each material is analyzed and compared. Then two typical materials are selected based on the experiment result of the six samples, which are later verified by the Compact Accelerator Neutron Source (CANS) facility. By using this method, the optimal result can be reached rapidly, and since the design progress is semi-automatic for most procedures are completed by computer, the method saves time and improves accuracy.

• Journal of Environmental Science International
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• v.32 no.10
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• pp.741-744
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• 2023

This study focused on high school laboratory research and the main purpose was to develop alternative additives for livestock waste and ammonia volatilization methods with high school students as participants and to provide information to business owners based on the results. Compared to the control groups, The bentonite and illite treatment groups had similar ammonia volatilization, pH, EC, and total nitrogen content. In particular, the alum and aluminum chloride mixed treatment group showed low pH and ammonia volatilization, and high EC and total nitrogen content for poultry litter. As a result, when focusing on high school laboratory research, the alum and aluminum chloride mixed agent treatment fulfilled its role as an alternative additive for ammonia reduction. In addition, this approach can be suggested as a method to solve difficulties in adapting to the field through a practical cooperative relationship with livestock farms.

• Asia pacific journal of information systems
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• v.32 no.1
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• pp.92-124
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• 2022

Providing services using kiosks is actively carried out between suppliers and consumers. These service processes have recently begun to play a dominant role in transactions. However, previous self-service technology (SST) studies or kiosks have not fully reflected the changing environment surrounding these different technologies. To cover the updated business environments, we combined qualitative and quantitative research methods. Through qualitative research and a review of previous studies, the variables emphasized as motivations and constraints for kiosks use and those that can be newly illuminated were selected for this study. We then applied the variables to the research model to assess their influence. In terms of the motivations for using kiosks, the results suggest that perceived usefulness and compatibility as service quality, forced use, and perceived service providers' efficiency as provider polices, absorptive capacity, and habit as an individual characteristic and social influence as a subjective norm have a significant effect on the attitude toward kiosks. In terms of constraints, difficult to use and need for interaction predicts the attitude toward kiosks. Attitude toward kiosks, perceived behavioral control, and social influence are directly related to the intention to use kiosks. Lastly, intention to use kiosks plays a significant role as an antecedent of revisit intention. Using these empirical results, we propose both academic and practical implications for future kiosks use.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.629-634
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• 2006

Clarified mixed fruit and vegetable (apple, carrot and orange) juices were prepared using different clarification methods including centrifugation, ultrafiltration (UF), and combined treatment with the blend ratio of 1:1:2, 1:2:1, and 2:1:1 (apple, orange and carrot). Effects of clarification methods on the clarification efficacy as well as other quality parameters were investigated. Clarification was improved with increase in centrifugation speed but was less affected by lowering temperature. Ultrafiltration process was very effective to produce clarified mixed fruit and vegetable juice. Combined treatment did not significantly improve the clarification efficacy since most clarification was already achieved during ultrafiltration process (p>0.05). L*- and b*-values increased while a*-value decreased significantly after clarification regardless of methods in all blend juices (p<0.05). Blend juices with high amount of orange or carrot were better in clarification efficacy and high amount of apple resulted in high turbidity in blend samples.