• Transactions of Materials Processing
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• v.14 no.4 s.76
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• pp.368-374
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• 2005

In the present study we used a diagrammatic analysis of 6 sigma quality control and Taguchi method for injection molding of monitor back-cover, evaluated the influence on the cycle time with part design, mold design, molding process and standardization activity involving design and molding, adopted analysis of sensitivity and effective factors of the part design and molding process conditions for productivity, identified main design molding factors. The contributing factors for the final cycle time could be enumerated as follows; the thickness of hot spot, main nominal part thickness, coolant inlet temperature, melt temperature and cooling line layout, etc.. As a first step, all the critical factors of design process applied to the current monitor housing were investigated through 6 sigma process. Thereafter, the optimal and better critical factors found in the first step were applied to new product design to prove that our process was correct. The Moldflow was used for injection molding simulation, and Minitab software for the statistical analysis, respectively. Finally, the productivity of new design was increased about 33 percents for our specific case.

• The Journal of the Korean dental association
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• v.53 no.2
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• pp.132-142
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• 2015

Purpose : The objective of this research was to investigate an optimization of drill design factors for implant stability and efficacy through comparative evaluation by the cutting time, heat generation and initial stability. Materials and Methods : Three design factors were considered for the purpose of drill design optimization; the number of flute(2 flute, 3 flute), helix angle($15^{\circ}$, $25^{\circ}$) and drill tip shape(straight, 2-phase). Design factors were selected through comparative evaluation by temperature change, cutting time and ISQ value. Results : Heat generation and cutting time are influenced by all design factors(p<0.05). Drill tip shape was the only factors which influenced to the largest initial stability(p<0.05). Conclusion : Drills with 2 flutes, 2-phase formed drill tip, and 25 degrees of helix angle exhibit a better performance than other design.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.157-170
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• 1997

A cross-sectional study was conducted to investigate the prevalence and risk factors for symptoms associated with sick building syndrome in four office buildings located in Seoul. Information on personal factors, job-related factors, and medical history were collected using self-administered questionnaires modified from the National Institute for Occupational Safety and Health Indoor Air Quality questionnaire in 321 office workers in these buildings. The prevalence of general and irritant symptom groups was higher than the prevalence of dermatologic and respiratory symptom groups. Daily total work time, work time in the office, and work time with video display terminals (VDT) were identified as the risk factors for symptom groups associated with sick building syndrome by multiple linear logistic regression analysis. In conclusion, these results indicated that the symptom prevalence in this study is similar with the results reported from previous studies conducted in other countries and work time and work with VDT are related to sick building syndrome in Korea.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.269-272
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• 2004

The present study used a diagrammatic analysis of 6 sigma quality control and Taguchi method for injection molding process of monitor back-cover, evaluated the influence on the cycle time with part design, mold design, molding process and standardization activity involving design & molding, adopted analysis of sensitivity and effective factors of the part design and molding process conditions for productivity, identified main design molding factors, as critical ones influencing on the quality and productivity, of which is summarized as design guidance. The main contribution factors for cycle time can be sequentially enumerated as follows; hot spot, part thickness, coolant inlet temperature, melt temperature cooling line layout, etc.. As a first step critical factors of the design process of current monitor housing were investigated. And the optimal and better critical factors found in the first step were applied to a new product proving our process was correct. Moldflow software was used for injection molding simulation, and Minitab software for the statistical analysis. Finally, the productivity was increased by about 33 percents for our specific case.

• Korean Journal of Human Ecology
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• v.13 no.1
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• pp.123-133
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• 2004

To investigate the factors that contribute to consumer satisfaction with the purchase of clothing, questionnaires were distributed and then consumer groups were classified according to their fashion life style on the internet shopping. The results were as follows: 1. Consumers groups were classified into trendy, Indifferent, brand inclined, conservative, and practicality- minded group by the fashion life style of the internet users. 2. From the analysis of the satisfaction factors on the internet clothing shopping, the factors were product variety, shopping convenience, customer service, confidence in order filling. 3. The most important consumer satisfaction factors according to the fashion life style were as follows: the trendy group considered the variety of clothing design most important. As for the Indifferent group, the tn, diversified collection of the products, and the convenience of unlimited time and space access that the internet site provided, were highly appreciated. With regard to the brand-inclined group, the presentation of product information and the convenience of unlimited time and space factors were highly appreciated. For the conservative group, the time and space factor were highly regarded, As far as the practicality-minded group was concerned, product price and size, the convenience of unlimited time and space access, and punctual delivery schedule were focused.

• International Journal of Highway Engineering
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• v.16 no.3
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• pp.109-117
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• 2014

PURPOSES : This study analyzes the available working time at work-zone on the Expressway in accordance to the new capacity manual. METHODS : Sensitivity analysis on variables were conducted to calculate the adjusted capacity at work-zone based on previous researches. RESULTS : The main factors which affect available working time at the work-zone were its capacity, number of lanes, terrain and lane width. Other factors have minimal effect on the available working time. Based on the analysis, a calendar of lane closures was suggested. CONCLUSIONS : A series of studies concluded that the capacity at work-zone in the new capacity manual reduced to 76-82% of the existing manual. As such, the available working time decreased. Furthermore, the factors affecting the available working time needs to be considered when making a plan to rehabilitate the distressed pavement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.177-178
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• 2022

As part of the study on the development of the setting time estimation system, this study attempted to confirm the change in hardness values for each influencing factor variable and secure its reliability. According to the research results of this paper, the hardness value of the setting time estimation system tended to gradually decrease in the case of the hardness value of the closing time by curing temperature, and the hardness value increased in the concrete state compared to mortar. Therefore, further research on influencing factors will be conducted in consideration of material and statistical factors in the future.

• Journal of the Korean Data and Information Science Society
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• v.27 no.6
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• pp.1511-1523
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• 2016

The increasing trend of the five violent crimes (murder, robbery, rape, violence, theft) in Korea is not independent of social and economic factors. Several social science research have discussed about this issue but most of them do not properly reflect the nature of the time-series data. Based on several time series models, we studied about the endogenous factors (time, seasonal and cycle factors) and exogenous factors (economical, social change and crime control factors) on violent crime occur in Korea. Autocorrelation were also taken into account. Through this study, we want to help to make preventive policy by explaining the cause of violent crime and predicting the future incidence of it.

• Korean Journal of Construction Engineering and Management
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• v.5 no.5 s.21
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• pp.93-100
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• 2004

For accurate construction contract time estimation, few parameters are more significant than crew production rates and factors affecting the rates. However, statistical analysis techniques for finding such factors are not always simple mainly because there are many factors and the interaction between factors is not well quantitatively understood. This paper presents methodology of identifying factors driving crew production rates. The methodology is further demonstrated with representative data collected by the author from 13 on-going highway constructions. Three factors were identified as statistically significant drivers of Cap crew production rate: 'Cap Size (m3/ea)'; 'Cap Length (m)'; and 'Cap Shape (Rectangle vs. Inverted 'T')'. It was also found that the production rates are best explained by a multiple regression model with two of the drivers; 'Cap Size' and 'Cap Shape'.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.10 no.2
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• pp.154-162
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• 2003

Purpose: The purpose of this study was to investigate factors which can delay hospital arrival for patients with acute stroke. Method: The participants for this study were 102 patients who were admitted to the Department of Neurology in a hospital in Chungnam province. Data were collected from Oct, 2002 to June, 2003. The data were analyzed with frequencies, percentages, and $x^2$ test using the SPSS PC program. Result: The results of this study were as follows: 1. Only 33.8 % of participants arrived at the hospital within 3 hours. 2. Educational level, economic status, people living in same residence, and place of residence were factors which significantly affected prehospital delay time. Also there were significant differences in prehospital delay time according to family history of stroke, day of the week when symptoms began, perception of seriousness of symptoms, type of hospital first used, and transportation. Conclusion: Therefore, to reduce prehospital delay time, educational programs which focus on the above factors need to be developed. Also, a public campaign for utilizing emergency service to reduce transportation time for acute stroke patients need to be facilitated.