• Transactions of Materials Processing
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• v.9 no.6
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• pp.615-623
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• 2000

The industrial application of hydroforming has a great potential in saying cost and achieving dimensional accuracy in automotive industry presently. The aim of the following article is to investigate the effect of process parameters on hydroformed part. Firstly, we have to investigate the change of mechanical properties for sheet and pipe material according to various radius/thickness ratio(r/t). The change of mechanical properties affects the yield stress more than the total elongation. Increase of yield stress for pipe has a bad influence on formability of hydroforming. Among the roll-forming process, the sizing process didn't change mechanical properties. The process parameters such as the initial pressure, mandrel shape and friction have seriously influenced on formability of hydroforming. Therefore we need to check formability of given material through the FE analysis in the beginning stage of process design and the predicted hydroforming process parameters ate generally a good starting point for the prototype tryout stage. The results of pretending, hydroforming analysis using FE model are good agreement with experimental results.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.355-360
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• 2000

There are many changed while a design is completed. Therefore, if the impact of the design changes is estimated, it may result in the improvement of design efficiency. But, the design changes have various types and affect other parts of the design system. Hence, it is difficult to deal with design changes directly. The purpose of this research is to develop a systematic change propagation tracing algorithm and a method of change impact analysis and then, to implement a change impact analysis system. Process based design is set up for the field of this research. Also the design, composed of design parameters and constraints, is set up for the subject of the research. Change propagation tracing algorithm traces change propagation based on the following concept : If the design parameters are changed, other parameters within the constrains including them may be changed. Using the result of change propagation tracing algorithm, changeable parameters, constraints and tasks can be found. The method of change impact analysis, to calculate change impact value from this changeable tasks, is developed. Change propagation tracing algorithm and the method of change impact analysis are implemented into change impact analysis system and it is applied to the redesign of 2 stage gear drives. It can support different kinds of design activities systematically. especially, at the redesign step, where many design change alternatives exist, change impact value of each alternative exist, change impact value of each alternative is calculated and design change is performed toward direction to minimize the impact of design change. Consequently, it is expected to improve the efficiency of the whole design.

• Proceedings of the KSRS Conference
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• v.2
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• pp.702-705
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• 2006

Change detection is a core function of remote sensing. It can be widely used in public services such as land monitoring, damage assessment from disaster, analysis of city growth, etc. However, it seems that the change detection using satellite imagery has not been fully used in public services. For the person who is in charge of public services, it seems not to be ease to implement the change detection because various functions are combined into it. So, to promote the use of the change detection in public services, the standard, the process and the method for the change detection in public services should be established. And the software which supports that will be very useful. This study aims to promote the use of satellite imagery in public services by building up the change detection process which are suitable for general public services and developing the change detection software to support the process. The software has been developed using ETRI Components for Satellite Image Processing to support the interoperability with other GIS software.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.156-163
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• 2008

Process change and modification, which are caused by process failure, equipment life cycle and economic environment, have been generated in the chemical plants. And the MOC (management of change) base on the reasonable process safety technology such as change judgment, hazard identification by accurate technical references and risk assessment. But it is difficult to carry out the MOC because of lack of experience, shortage of knowledge and none of process safety specialists. In this study, the MOC system which could make enhancement of safety by finding and complementing weakness of MOC in chemical facilities was developed. This developed MOC system based on QRA was recommended the obvious standard for decision-making process, MOC procedure based on risk assessment and risk estimation of the process modification. The study based on the above way sought the enhancement of safety by performing Risk Based MOC for chemical plants.

• Journal of Korean Academy of Nursing
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• v.32 no.2
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• pp.155-164
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• 2002

With the dynamically changing environment of society, managing change is the vital element of organizations's survival and growth. Health care organizations have expended enormous resources to restructure patient care delivery. Despite the growing literature describing these organizational innovations, there is a paucity of credible data that reflects systematic measurement and evaluation of such changes. This study examined the nurses' psychological response toward the work process redesign, newly introduced by the nursing department in a acute care hospital. The aim of the study was to figure out how nurses's general perception of change and perceived attributes of change affected their acceptance of change during the organizational transition. This was descriptive- correlational. The sample for the study included 50 head nurses and 135 staff nurses. Data was analyzed using SPSS PC+, version 10.0. The major findings of the study were as follows: First, the mean score of the perception of change was 71.2(SD=13.8) with the range of 0-100, which means nurses generally perceived change positively. There were significant differences in perception of change by gender and education level. Head nurses perceived change more positively than staff nurses. The higher education level showed the more positive view of change. Second, among the perceived attributes of change, trialability had the highest mean score, which means nurses perceived the change more positively if it is testable on a limited basis. Relative advantage was perceived the most negatively. Finally, factors influencing the acceptability of the work-process redesign were perceived comparability, complexity, relative advantage, and observability, which accounted for 43.7% of the variance in the acceptability of change. This study evaluated the preliminary effects of the nursing process for reengineering, focusing on nurses' acceptability towards change. The usefulness of this research study was to determine the factors influencing acceptance of organizational members during transitional periods of change and to suggest effective strategies for increasing adoption as well as for decreasing resistance to change.

• Korean Journal of Adult Nursing
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• v.15 no.2
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• pp.236-246
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• 2003

Purpose: The purpose of this study was to examine the differences of the process of change, decision making, self-efficacy and perception of subjective health according to the stages of exercise behaviors suggested by transtheoretical models among older adults. Method: The subjects consisted of 291 older adults. Trained research assistants interviewed the older adults using structured questionnaires. ANOVA analyses with post hoc test were used to examine the mean differences for each stage of exercise behavior using SPSS for windows. Result: The subjects were divided into five stages of exercise behavior: 24.4% precontemplation, 12.4% contemplation, 17.9% preparation, 12.4% action, 33.0% maintenance stage. There were significant differences in process of change, decision making, self-efficacy and subjective health perception according to the exercise stage of change. 'Self-liberation' and 'stimulus control' were important strategies for intention of exercise, while 'reinforcing management' for the actual practice of exercise. 'Self-efficacy' was an effective strategy to change older adults from pre-contemplation to preparation stage. Conclusion: For exercise intervention, older adults should be classified into groups according to their stages of exercise behaviors and provided effective individualized intervention depending on their stage.

• Journal of Korean Institute of Industrial Engineers
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• v.36 no.3
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• pp.154-163
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• 2010

Process monitoring of output variables affecting final performance have been mainly executed in semiconductor manufacturing process. However, even earlier detection of causes of output variation cannot completely prevent yield loss because a number of wafers after detecting them must be re-processed or cast away. Semiconductor manufacturers have put more attention toward monitoring process inputs to prevent yield loss by early detecting change-point of the process. In the paper, we propose the method to efficiently monitor functional input variables in multi-phase semiconductor manufacturing process. Measured input variables in the multi-phase process tend to be of functional structured form. After data pre-processing for these functional input data, change-point analysis is practiced to the pre-processed data set. If process variation occurs, key variables affecting process variation are selected using contribution plot for monitoring efficiency. To evaluate the propriety of proposed monitoring method, we used real data set in semiconductor manufacturing process. The experiment shows that the proposed method has better performance than previous output monitoring method in terms of fault detection and process monitoring.

• Journal of Information Technology Services
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• v.9 no.1
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• pp.1-25
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• 2010

Many organizations are facing larger and more frequent changes in the current economic and managerial environment. And what is more, change is supposed to be a business as usual. Considering the importance of change management process and the organizational competency to rapidly and successfully change, in this study the components of change management maturity(CMM) was selected such as the leadership, communication, resistance, people culture factor, methodology, functional group, and change review. And information system performance affected by CMM is confined to the efficiency and effectiveness of information systems. Some results from the verification of research hypotheses and the analysis of the most appropriate model was drawn out. The result of this study can be applied to all organizations which plan to manage more successful change and implement more effective information systems.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.434-435
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• 2008

An in-situ monitoring technique for deposition process of CdS buffer layer was developed in this work. A quartz crystal microbalance (QCM) was used to measure the frequency change during the CdS deposition process and the relation ship between frequency change and film thickness and optical transmittance was investigated. The film thickness shows a linear relationship with frequency change, demonstrating that frequency change measured by QCM can be used a in-situ monitoring tool for CdS deposition process.

• Journal of the Korean Society of Visualization
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• v.1 no.2
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• pp.52-57
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• 2003

The present paper investigated the effect of ultrasonic vibrations on the melting process of a phase-change material (PCM). The melting process in the square cavity with a heated vertical wall has been studied in terms of acoustic streaming. In the present study, applying with ultrasonic vibrations to the liquid were found to induce acoustic streaming which was clearly observed using by a particle image velocimetry (PIV) and a thermal infrared camera. The experimental results revealed that acoustic streaming could accelerate the melting process as much as 2.5 times, compared to the rate of natural melting (i. e., the melting without acoustic streaming). In addition, temperature and Nusselt numbers over time provided conclusive evidence of the important role of the acoustic streaming on the melting phenomena of the PCM.