• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4567-4575
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• 2016

A number of studies have evidenced the effect of modifiable lifestyle factors such as diet, breastfeeding and nutritional status on breast cancer risk. However, none have addressed the missing data problem in nutritional epidemiologic research in South America. Missing data is a frequent problem in breast cancer studies and epidemiological settings in general. Estimates of effect obtained from these studies may be biased, if no appropriate method for handling missing data is applied. We performed Multiple Imputation for missing values on covariates in a breast cancer case-control study of $C{\acute{o}}rdoba$ (Argentina) to optimize risk estimates. Data was obtained from a breast cancer case control study from 2008 to 2015 (318 cases, 526 controls). Complete case analysis and multiple imputation using chained equations were the methods applied to estimate the effects of a Traditional dietary pattern and other recognized factors associated with breast cancer. Physical activity and socioeconomic status were imputed. Logistic regression models were performed. When complete case analysis was performed only 31% of women were considered. Although a positive association of Traditional dietary pattern and breast cancer was observed from both approaches (complete case analysis OR=1.3, 95%CI=1.0-1.7; multiple imputation OR=1.4, 95%CI=1.2-1.7), effects of other covariates, like BMI and breastfeeding, were only identified when multiple imputation was considered. A Traditional dietary pattern, BMI and breastfeeding are associated with the occurrence of breast cancer in this Argentinean population when multiple imputation is appropriately performed. Multiple Imputation is suggested in Latin America's epidemiologic studies to optimize effect estimates in the future.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.141-147
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• 2009

This paper reports on a study to increase the flexibility of previous TMDS(Train Monitoring and Diagnosis System) network communication in case of both multiple units and variable train sets. The previous TMDS network configuration has been applied using various field-BUS by the TMDS manufacturers using their own intrinsic method. But recently, there has been a demand for flexible train formations such as multiple units and variable train set formations, hence the TMDS had to be adapted to offer flexible network communication technology capability. Therefore, Hyundai-Rotem needed its intrinsic method of network configuration, and develop a network configuration method applicable to both multiple units and variable train set formations. The TMDS was integrated into the Irish Rail new Diesel Multiple Units from an early stage of the project and subsequently fully tested on a finished train.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.4
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• pp.259-267
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• 2002

Objective: This study was performed to compare the clinical outcomes of GnRH antagonist (Cetrorelix) single dose and multiple dose protocols for controlled ovarian hyperstimulation with GnRH agonist long protocol. Materials and Method: From September 2001 to March 2002, 48 patients (55 cycles) were performed controlled ovarian hyperstimulation for ART using by either GnRH antagonist and GnRH agonist. Single dose of 3 mg GnRH antagonist was administered in 15 patients (17 cycles, single dose group) at MCD #8 and multiple dose of 0.25 mg of GnRH antagonist was administered in 15 patients (18 cycles, multiple dose group) from MCD #7 to hCG injection day. GnRH agonist was administered in 18 patients (20 cycles, control group) by conventional GnRH agonist long protocol. We compared the implantation rate, number of embryos, and clinical pregnancy rate among three groups. Student-t test and Chi-square were used to determine statistical significance. Statistical significance was defined as p<0.05. Results: There were no significant differences in ampules of used gonadotropins, number of mature oocytes, obtained embryos between single and multiple dose group, but compared with control group, ampules of used gonadotropins, number of mature oocytes, obtained embryos were decreased significantly in both groups. Clinical pregnancy rate and implantation rate were not different in three groups. There were no premature LH surge and ovarian hyperstimulation syndrome in three groups. Multiple pregnancy were occurred 1 case in multiple dose group and 2 case in control group. Conclusions: GnRH antagonist is a safe, effective, and alternative method in the controlled ovarian hyperstimulation compared with GnRH agonist. Clinical outcomes and efficacy of both single and multiple dose protocol are similar between two groups.

• Journal of Korean Institute of Industrial Engineers
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• v.43 no.2
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• pp.127-134
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• 2017

For product or process design and development, it is common to optimize multiple responses (characteristics) based on experimental data. To determine optimal conditions, we need to design the experiment, estimate a proper model for each response, and optimize the multiple responses simultaneously. There are several techniques and many research results on optimizing multiple responses simultaneously, when the experimental data are available. However, the experimental design issue for optimizing multiple responses has not been discussed yet. This paper proposes some idea on how to plan screening design when requirements for multiple performance characteristics are to be met in developing new products. A screening design procedure is developed for securing the requirements of multiple responses. Initial design factors are classified into three categories; specific, non-conflicting common, and conflicting common. After screening experiments, follow-up design region search method is suggested with respect to the most unsatisfied or important response, or overall desirability. A case study on a synthesis of melamine formaldehyde resin is presented to illustrate the procedure and to show the validity of the approach.

• Korean Journal of Construction Engineering and Management
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• v.10 no.6
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• pp.127-134
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• 2009

This study aims to provide an optimal model for the layout of multiple tower cranes and material stockyards which have multiple candidate positions. In a high-rise building construction, the positional allocation of tower cranes and material stockyard has an effect on the travel time of material hauling. In addition, in case of using multiple tower cranes, specific location of a tower crane allocated to each material determines the efficiency of the works. Current optimal model limited to the optimization of position of single tower crane and material stockyards. This study suggests optimal model both for the positions of multiple tower cranes and material stockyards. Layout of multiple tower cranes requires additional allocation of each crane to each material hauling and control on the minimum distance between tower cranes. This optimization model utilizes genetic algorithm to deal with complex interaction on the candidate positions of multiple tower cranes, material stockyards, and types of materials. In order to identify its utility, case study was performed.

• The Korean Journal of Rehabilitation Nursing
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• v.18 no.2
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• pp.98-106
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• 2015

Purpose: The purpose of this study was to compare the needs of case management between Medical aid beneficiaries with simple and multiple chronic diseases (SCD vs MCD). Methods: The study employed secondary analysis method using a cross-sectional data from 2009 case management service enrollees. Data on 35,862 beneficiaries who have chronic disease(s) were used in the description of chronic disease characteristics, and data on 20,392 beneficiaries, excluding those who have depression and/or disabilities, were used to compare the group differences. Results: Mean age was $68.8{\pm}11.63years$, and 73.3% were females. MCD group showed an older age, had more women than SCD group. Self-care ability and appropriateness of health care utilization were significantly different between the groups, but there was no difference in health-related quality of life. In subscales, there were significant differences in general health status, depression, symptom management, healthy lifestyle, hygiene and vaccination, and appropriateness of health utilization. Conclusion: Different characteristics between patients with simple and multiple chronic diseases indicate that different case management approaches are required for these groups. The study results could be used as a basis for the development of case management model tailored to the characteristics and needs of medical-aid beneficiaries.

• International Journal of Highway Engineering
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• v.14 no.4
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• pp.83-91
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• 2012

PURPOSES : This study deals with Rotary by Accident Occurrence Location. The purpose of this study is to develop the accident models of rotary by location. METHODS : In pursuing the above, this study gives particular attentions to developing the appropriate models using multiple linear, Poisson and negative binomial regression models and statistical analysis tools. RESULTS : First, four multiple linear regression models which are statistically significant(their $R^2$ values are 0.781, 0.300, 0.784 and 0.644 respectively) are developed, and four Poisson regression models which are statistically significant(their ${\rho}^2$ values are 0.407, 0.306, 0.378 and 0.366 respectively) are developed. Second, the test results of fitness using RMSE, %RMSE, MPB and MAD show that Poisson regression model in the case of circulatory roadway, pedestrian crossing and others and multiple linear regression model in the case of entry/exit sections are appropriate to the given data. Finally, the common variable that affects to the accident is adopted to be traffic volume. CONCLUSIONS : 8 models which are all statistically significant are developed, and the common and specific variables that are related to the models are derived.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.108-115
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• 2018

Time is considered as an important factor to understand the diffusion behavior of single generation technology. However, multiple generation technology required additional factors in addition to time to understand the diffusion behavior. This study defined the diffusion path of multiple generation technology based on dimensions of 'time, price, and performance' after extracting price and technical performance factors and traced the diffusion path of semiconductor industry based on defined dimensions. The case study of semiconductor industry indicated that the diffusion path is determined maximizing the integrated area of price and performance. This study has theoretical implications in that it analyzed the diffusion behavior of multiple generation technology based on multiple dimensions and can forecast the diffusion behavior at matured as well as early stage technology. Also, this study has practical implications for R&D and marketing managers to understand time-to-market, exit time, and economical as well as technical requirements.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.6
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• pp.292-297
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• 2014

Nevoid basal cell carcinoma syndrome (NBCCS) is a rare autosomal genetic disease caused by a PTCH mutation. The disease is characterized by multiple basal cell carcinomas of the skin, multiple keratocystic odontogenic tumors (KCOTs) in the jaw, palmar and/or plantar pits, bifid ribs, ectopic calcification of the falx cerebri, and skeletal abnormalities. Early diagnosis is difficult in many cases because there may be a number of systemic symptoms. The purpose of this study is to report the case of a 12-year-old girl who was hospitalized with multiple KCOTs that occurred in the upper and lower jaws. Through characteristic clinical symptoms and radiologic findings, she was finally diagnosed as having NBCCS. This study also aims to organize the symptoms often observed in Korea using previously published case reports to provide useful information for the early diagnosis of NBCCS.

• Journal of Korean Society for Quality Management
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• v.12 no.2
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• pp.25-32
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• 1984

The purpose of this paper is to compare several forecasting methods for the case of the cement product by the analysis of the forecasting data and by the study of major forecasting methods, which are the Trend Projection, Exponential Smoothing, and Multiple Regression Analysis. As a result, it is thought that the Multiple Regression Analysis is the optimal model for the case of the cement product. In addition, it is important to consider the future circumstances for forecasting, and to improve the level of the forecasting results through the precise analysis of the collected data.