• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.339-345
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• 1998

The creep of concrete structures caused by variable stresses is mostly calculated by step-by-step method based on the superposition of creep function. Although most practical application is carried out by this linear assumption, significant deviations between predictions and experiments have been observed when unloading takes place, that is, stress is reduced. The recovery is overestimated. The main purpose of this study is to present the application method of the creep analysis model which is expressed with both creep function and creep recovery function to concrete structures where is expressed with both creep function and creep recovery function to concrete structures where increase or decrease of stress is repeated . To apply two function method to time analysis of concrete structures, this study presents the calculation method of creep strain increment for stress variation. Then, this paper executes the time analysis for an example using suggested method, and compares theses results with the previous analysis values and experimental results.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.812-815
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• 2007

To apply the superconducting fault current limiter(SFCL) into a power system, the analysis for its recovery characteristics as well as the consideration for its cooperation with other protecting machine such as a circuit breaker is required. The recovery characteristics of the flux-lock type SFCL like its current limiting characteristics are dependent on the winding direction of two coils. In this paper, the experiments of the current limiting and the recovery characteristics of the flux-lock type SFCL with YBCO thin film were performed. From the analysis on the experimental results due to the winding direction of two coils, the limited fault current in case of the additive polarity winding was observed to be lower than that for the case of the subtractive polarity winding. In addition, the recovery time was found to be faster in case of the additive polarity winding compared to the subtractive polarity winding.

• Journal of the Korean Applied Science and Technology
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• v.39 no.5
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• pp.596-604
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• 2022

This study aimed to examine the mediating effects of anxiety between adolescents' smartphone overdependence and fatigue recovery, and to secure the evidence data for adolescents' smartphone overdependence intervention. Among the 16th Korea Youth Risk Behavior Survey, 54,948 students were included. Data were analyzed using Pearson correlation coefficients, factor analysis, mediating effect analysis. The results were as follows. Smartphone overdependence had a direct effect on fatigue recovery and an indirect effect on fatigue recovery through anxiety. Smartphone overdependence had a significant effect on anxiety and fatigue recovery. Also, anxiety is verified as the mediation effect between smartphone overdependence and fatigue recovery. When we prepare intervention programs which improve fatigue recovery for adolescents, we need to consider anxiety.

• Knowledge Management Research
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• v.16 no.1
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• pp.71-93
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• 2015

With the rapid growth of the internet, electronic commerce has become accepted as one of the major purchasing channels for consumers. As more and more consumers search for and purchase products through the internet, intra-industry competition of electronic commerce has become fierce. Therefore, electronic commerce service providers pay attention to factors that prevent existing customers from leaving there services in the service failure situation. In this regard, electronic commerce service providers should make service recovery efforts for consumer recovery satisfaction after service failure. In this study, we suggest that procedural justice, interactional justice, distributive justice and authenticity have positive impacts on recovery satisfaction. In addition, we also propose that involvement plays moderating roles in the relationships between procedural justice, interactional justice, distributive justice, authenticity and recovery satisfaction. We collected empirical data for this study over a period of two weeks from subjects who had service failure recovery experiences through electronic commerce. A total of 224 complete and valid responses were obtained. We carried out data analysis using a two-step methodology with SPSS 20.0 and SmartPLS 2.0. The first step in the data analysis was to establish the internal consistency, convergent validity, discriminant validity of the constructs. In the second step, we examined the structural model. The empirical results support the proposed model and partly identify the moderating effect of involvement differences. The moderate effect results show that procedural justice, distributive justice and authenticity have different impacts on recovery satisfaction in two groups. Cognitive factor such as the procedural justice and distributive justice have stronger impacts on recovery satisfaction in the high-involvement goods than in the low-involvement goods, while emotional factor such as authenticity has a stronger impact on recovery satisfaction in the low-involvement goods than in the high-involvement goods. We expect that this result will provide researchers and managers who are interested in electronic commerce service failure recovery with useful theoretical and practical implications.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.1 s.20
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• pp.32-38
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• 2005

In this study, Experimental analysis on submarine cable tension was performed for the safe and efficient laying and recovery of a submarine cable. The tension analysis was done through the analyzed data using the cable dynamic theory and the measured data using the experiment. The analyzed cable tension was able to decide requirements for the purpose of laying and recovery of the submarine cable. As the result of tension analysis for a Submarine cable, it was shown a proper feasibility to determine the laying and recovery conditions of the submarine cable.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.5
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• pp.521-528
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• 2017

In the combustion treatment of explosive gases with a high heating value such as $H_2$ and $NH_3$ used in semiconductor and chemical processes, the heat recovery modeling and exergy analysis of the process using the Aspen Plus simulator and its thermodynamic data were performed to examine the recovery of high temperature thermal energy. The heat recovery process was analyzed through this process modeling while the exergy results clearly confirmed that the rigorous reaction mainly occurs in the condenser and the chamber. In addition, the process modeling demonstrated that approximately 95% of the exergy is destructed on the basis of the exergies injected and the exergy being exhausted. Using the exergy technique, which can quantitatively analyze the energy, we could understand the energy flow in the process and confirm that our heat recovery process was efficiently designed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.312-316
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• 2004

Single-well tracer tests, especially push pull tracer tests, are more effective to estimate hydraulic parameters and microbial metabolic activities in terms of duration and cost compared to multi-well tracer tests. However, there are some drawbacks in accuracy, complicated data analysis and uniqueness. These shortages are thought to be derived from the applied conditions which affect mass recovery curve and breakthrough curve. Factors such as extraction rate, resting period, hydraulic conductivity and hydraulic gradient are considered as the major factors determining the mass recovery rate and shape of the breakthrough curve. The results of the sensitivity analysis are summarized as follows: 1) the significant change in concentration of breakthrough curve is obtained when the extraction rate increases. This effect would also be much higher if the hydraulic conductivity is lower; 2) the mass recovery rate decreases with the increase of resting time, and the difference of mass recovery rates for different resting times is inversely proportional to the hydraulic conductivity; 3) the sensitivity values decrease with time. The hydraulic conductivity affects not only the early period, but the later period of the breakthrough curves; 4) The influence of the hydraulic gradient on the breakthrough curves is greater at earlier stage than at later stage. The mass recovery rate is inversely proportional to the hydraulic gradient.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.6
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• pp.5-11
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• 2003

The number of the enterprises which utilize network technology has been increasing for solving problems such as productivity improvement, market trend analysis, and material collection for making decision. Especially, the management of equipment and the recovery time reduction when machines break down are very important factors in productivity improvement of the enterprise. Currently, most of the remote trouble diagnosis of equipment using the internet have just one function of transmitting the trouble information to the user. Therefore it does not directly reflect the user's recovery experience or the developer's new recovery methods. If the user's experienced recovery methods or the developer's recovery methods as well as the basic recovery methods are reflected online or on the internet, it makes it possible to recover faster than before. In this paper, we develop a Remote Monitoring Server (RMS) for chip mounters, and make it possible to reduce the recovery time by reflecting the user's experience and developer's new methods in addition to presenting the basic recovery methods. For this, trouble recovery concept will be defined. Based on this, many functions(trouble diagnosis, the presentation of the basic recovery methods, user's and developer's recovery method, counting function of the trouble number of each code, and presentation of usage number of each recovery methods) were developed. By utilizing the reports of the actual results of chip mounter and the notice function of the parts change time, the rate of operation of the chip mounter can be improved.

• Journal of Distribution Science
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• v.18 no.2
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• pp.91-98
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• 2020

Purpose: This research aimed to suggest retailing companies some ways to enhance customer satisfaction with service recovery and recommendation intention towards these companies. For this purpose, current study examined the relationships among service recovery justice, service failure severity, customer trust, recovery satisfaction and intention to recommend and the moderating role of ego-resilience. Research design, data and methodology: Current study developed a structural equation model in which perceived service recovery justice is a predictor, service failure severity, customer trust, recovery satisfaction are mediators, intention to recommend is a dependent variable and the ego-resilience is a moderator between the perceived service recovery justice and the customer trust and the recovery satisfaction. Data were collected from customers who experienced service failures from retailers. A total of 400 questionnaires were collected and 365 samples were used for analysis after deleting data having missing value. SPSS 25.0 and AMOS 24.0 were used to test the validity, reliability, and structural equation modeling. Results: Empirical results showed that the perceived service recovery justice had a negative influence on the perceived service failure severity and a positive influence on the customer trust and the recovery satisfaction. These results indicate that when customers perceive the service recovery justice more highly, they perceive the service failure less severe but they perceive the retailer more trustworthy and are satisfied with service recovery. In addition, the customer trust and the recovery satisfaction had a positive influence on the intention to recommend. These results indicate that when customers perceive the retailer more trustworthy and are satisfied with service recovery, they are more intend to recommend the retailer. Moreover, the influence of the perceived service recovery justice on the customer trust and the recovery satisfaction was moderated by the ego-resilience. Conclusions: This study contributed to the service recovery literature by proving the relationship among service recovery justice, service failure severity, customer trust, recovery satisfaction and intention to recommend. Moreover, current research introduced the ego-resilience into service recovery research area and revealed the moderation role of the ego-resilience. Managerially, this research suggested retailing companies some ways to effectively recover from service failure.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.179-182
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• 1998

Carrier recovery, the process of recoverying the carrier in receiver, removes the phase difference between VCO and the received signal. However, the conventional structure of carrier recovery cannot be applied to multi-level QAM demodulator because of the increasing decision interval and the complexity of control as the number of symbol increases. In this paper, we suggest a new carrier recovery algorithm using $\theta-matching$ algorithm for multi-level QAM demodulation to overcome this problem and analysis the performance and implement it.