• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.87-95
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• 2007

The ocean and meteorological payloads of COMS are concerned to experience degration of image quality due to the disturbance induced by the motion of moving parts of the payloads. And thruster firings for stationkeeping and wheel offloading are expected to degrade the image quality of the optical payloads. In case of COMS, in order to keep the optical payload free from the mechanical interference from the other payload, the operation design approach has been taken. This paper introduces the operation design of COMS taken to avoid these problems. In order to meet users requirement by avoiding the degradation of image quality, the timeline of optical payloads and housekeeping are optimized, and operational constraints are applied to the mirror motion of the meteorological payload. This paper also introduces the results of time budget analysis performed to validate the operation design.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2S
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• pp.649-655
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• 2000

Real-time application programs have constraints which need to be met between media-data. These constraints represents the delay time ad quality of service between media-data to be presented. In order to efficiently describe the delay time and quality of service, a new synchronization mechanism is needed. Proposed paper is a dynamic synchronization that minimized the effects of adaptive transmission delay time. That is, the method meets the requirements of synchronization between media-dat by handling dynamically the adaptive waiting time resulted from variations of delay time. In addition, the mechanism has interval adjustment using maximum delay jitter time. This paper decreases the data loss resulted from variation of delay time and from loss time of media-data by means of applying delay jitter in order to deal with synchronization interval adjustment. Plus, the mechanism adaptively manages the waiting time of smoothing buffer, which leads to minimize the gap from the variation of delay time. The proposed paper is suitable to the system which requires the guarantee of high quality of service and mechanism improves quality of services such as decrease of loss rate, increase of playout rate.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.55-63
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• 2009

Purpose: This study evaluated of quality of life (QOL) and physical therapy satisfaction (PTS) in caregivers of cerebral palsy children. Methods: Eighty six caregivers in Gwang-ju were examined. The caregivers' QOL was assessed through self-reports using the WHO Quality of Life-BREF (WHOQOL-BREF), and the data was analyzed separately for each of its 5 domains. Physical therapy satisfaction was assessed using a self-reported questionnaire and the data was analyzed separately for the 2 domains. The results were processed by the mean and standard deviation and then verified by ANOVA and a t-test to determine the significant differences in the QOL and PTS. The factors affecting the QOL were processed by logistic regression. Results: Life environment domain of the QOL across the caregivers factors showed a statistically significant difference in age at natal, monthly income and education. The birth order in the cerebral palsy child factor showed a significant difference in the general, physical and emotional domain of the QOL. The PTS showed a significant difference in the delivery of therapy domain and in the birth order and walking condition of the environment domain. Caregivers education was found to be associated independently with the life environment domain of QOL. Conclusion: Because the QOL of caregivers is an important treatment goal for children with cerebral palsy, early family intervention should be considered.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.2
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• pp.90-95
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• 2001

Electric arc furnaces (EAFs) has a process to cause the degradation of the electric power quality such as voltage flicker. In order to adequately understand and analyze the effects on the power system from these loads, obtaining an accurate representation of the characteristics of the loads is crucial. In this paper, a mixed chaotic EAF model to represent the low frequency and high frequency variations of the arc current respectively has been proposed. The Lorenz system may contribute to the low frequency components of arc current and the logistic equation may contribute to the high frequency components, and the proposed mixed model will be a combination of both Lorenz and logistic model. The concept of chaotic parameters, such as chaotic resistance, inductance of admittance has been also proposed for the characterization of arc furnace operation and the highly nonlinear physical processes. The power quality indices are calculated from the simulated waveforms and compared with the actual power quality indices statistics in order to illustrate the model's capabilities.

• Water for future
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• v.14 no.4
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• pp.19-26
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• 1981

The auto-and cross-correlation function, power spectrum, coherence function and Markov model are applied to investigate the statistical characteristics of discharge and each factor of water quality and the interrelation-ship between the variation of discharge and water quality factors. The analysis of discharge, dissolved oxygen and electric conductivity, which were only obtainable data at the Indogyo gagining station in the downstream of the Han River, clearly showed that they hace distinct period of 12 months and three different periods of 6, 4 and 3 months weaker than the former. The cross-correlation between the discharge and water quality(DO, COND) is rather weak and the crosscorrelation function has its peak at lag one. It is considered therefrom that the variation of discharge behaves on water quality facotrs with one day's difference. In the examination of linear regression model for the serial generation and predictive measures, discharge series is fit to first and second order Markov model and DO, COND to first order Markov model.

• International Journal of Quality Innovation
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• v.3 no.2
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• pp.13-28
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• 2002

Higher efficiency and effectiveness of Research & Development phases can be attained using advanced statistical methodologies. In this work statistical methodologies are combined with a deterministic approach to engineering design. In order to show the potentiality of such integration, a simple but effective example is presented. It concerns the problem of optimising the performances of a paper helicopter. The design of this simple device is not new in quality engineering literature and has been mainly used for educational purposes. Taking full advantage of fundamental engineering knowledge, an aerodynamic model is originally formulated in order to describe the flight of the helicopter. Screening experiments were necessary to get first estimates of model parameters. Subsequently, deterministic evaluations based on this model were necessary to set up further experimental phases needed to search (or a better design. Thanks to this integration of statistical and deterministic phases, a significant performance improvement is obtained. Moreover, the engineering knowledge かms out to be developed since an explanation of the “why” of better performances, although approximate, is achieved. The final design solution is robust in a broader sense, being both validated by experimental evidence and closely examined by engineering knowledge.

• Journal of Industrial Convergence
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• v.13 no.3
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• pp.27-39
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• 2015

This Study aims to analyze the management performances of the rubber products from the perspectives of ISO9001 Quality Management System, which is a new management technique for management innovation, in order to secure the competitiveness of the small and medium manufacturers of rubber products for automobile as automobile application components. The results of the analysis can be summarized as follows: First, as the results of the analysis of effect of the (1) responsibility of the management, (2) resources management, (3) realization of the products, and (4) measurement, analysis and improvement, which are the 4 core requirements of the ISO9001 Quality Management System, on the management performances of the small and medium sized manufacturers of the rubber components for automobile, it was found that only the responsibility of the management and resources management affect the management performance. The above research findings imply that the company must absolutely rely on the upper ranked groups rather than the lower ranked groups, and on the responsibilities of the management rather than the upper ranked groups in order to elevate the management performance of the small and medium sized manufacturers of the rubber components for automobile.

• The Journal of Industrial Distribution & Business
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• v.12 no.2
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• pp.19-27
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• 2021

Purpose: This study investigated the impact of key factors such as service quality, perceived benefit and brand familiarity on a consumer's intention to order online food delivery (OFD). In addition, mediating effect of electronic word of mouth (e-WOM) between relationships among selected key variables and OFD purchase intention is also assessed. Research design, data and methodology: This explanatory, quantitative study employed convenience sampling and collected data through online structured questionnaire from 304 respondents who are users of OFD apps based in greater Klang valley region of Malaysia. The data was then subjected to normality and reliability assessment followed by confirmatory factor analysis, validity assessment and structural equation modelling using IBM SPSS AMOS 24.0. Results: Findings revealed that service quality, perceived benefits and brand familiarity affects purchase intention positively and significantly. Perceived benefits demonstrated highest impact on purchase intention followed by brand familiarity and service quality. Findings also suggest that e-WOM fully mediates relationship between brand familiarity and purchase intention, however, the same was not observed for remaining two variables. Conclusions: The study has enriched OFD literature by investigating impact of selected key factors on purchase intention in the context of OFD. Implications, limitations and future research avenues are then discussed.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.181-189
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• 2022

The purpose of this study is to verify study models and examine a causal relationship among authenticity, job satisfaction, organizational commitment, quality of life and job achievement for amateur business team player. In order to achieve the purpose, this study conducted structural equation model analysis for study models consisting of extraneous variables after examining the authenticity(organization, leader) that amateur business players perceive and endogenous variables including job satisfaction, organizational commitment, quality of life, and job performance. The object of questionnaires in this study selected sports business team players nationwide as a population and 348 players were chosen as final effective samples by applying a convenient sampling method for offline and online questionnaires. The research tool for this study is a questionnaire. The two dimensions of authenticity were used by developing a scale. For all endogenous variables, the scales used in previous studies were modified and used according to the purpose of the study. This study analyzed the collected data, applying SPSS Win ver. 23.0 and AMOS 20.0 programs in order to analyze the characteristics of the study objects, describe questionnaires, and verify selected study hypothesis, individual hypothesis was verified after identifying the reliability and validity of measurement model, and the fitness verification of study models. In the results, all of the 8 hypothesis were adopted and the reciprocal relationship among each factors in the study model were observed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.347-353
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• 2008

Generally speaking, it is important to know the activities itself exactly and to control the activities correctly so as to assure timely progress and the quality of any project. In order to progress smoothly in accordance with construction schedule, it is important to systematize the preliminary arrangements necessary for each process and then manage them. In this study, in order to progress smoothly the quality and schedule management of the construction, we can be made systematically pre-works in accordance with construction schedule by the civil construction items of the apartment house construction. we suggested pre-construction control item by the workers through experiential method of construction engineers in accordance with network schedule.