• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8371-8376
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• 2014

Background: The use of statistical methods has become an imperative tool in breast cancer survival data analysis. The purpose of this study was to develop the best statistical probability model using the Bayesian method to predict future survival times for the black non-Hispanic female breast cancer patients diagnosed during 1973-2009 in the U.S. Materials and Methods: We used a stratified random sample of black non-Hispanic female breast cancer patient data from the Surveillance Epidemiology and End Results (SEER) database. Survival analysis was performed using Kaplan-Meier and Cox proportional regression methods. Four advanced types of statistical models, Exponentiated Exponential (EE), Beta Generalized Exponential (BGE), Exponentiated Weibull (EW), and Beta Inverse Weibull (BIW) were utilized for data analysis. The statistical model building criteria, Akaike Information Criteria (AIC), Bayesian Information Criteria (BIC), and Deviance Information Criteria (DIC) were used to measure the goodness of fit tests. Furthermore, we used the Bayesian approach to obtain the predictive survival inferences from the best-fit data based on the exponentiated Weibull model. Results: We identified the highest number of black non-Hispanic female breast cancer patients in Michigan and the lowest in Hawaii. The mean (SD), of age at diagnosis (years) was 58.3 (14.43). The mean (SD), of survival time (months) for black non-Hispanic females was 66.8 (30.20). Non-Hispanic blacks had a significantly increased risk of death compared to Black Hispanics (Hazard ratio: 1.96, 95%CI: 1.51-2.54). Compared to other statistical probability models, we found that the exponentiated Weibull model better fits for the survival times. By making use of the Bayesian method predictive inferences for future survival times were obtained. Conclusions: These findings will be of great significance in determining appropriate treatment plans and health-care cost allocation. Furthermore, the same approach should contribute to build future predictive models for any health related diseases.

• Journal of Korean Society for Quality Management
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• v.45 no.1
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• pp.55-64
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• 2017

Purpose: A large number of attributes with mixed levels are often considered in the conjoint analysis. The respondents may have difficulty with scoring their preferences accurately because of many attribute items involved in each survey question. We research on the technique for reducing the number of attribute items. Methods: In order to reduce the number of attribute items in a survey question, we make a new attribute by merging two original attributes. A 'No question' option is also included as a new level in a merged attribute. Results: We propose BIB $6^4$ design in the case where we have four attributes with 2 levels and 3 levels, respectively and then analyze all the respondents survey data generated by the repeated simulation study in order to compare various model selection methods. Conclusion: How to reduce the number of attribute items is proposed and how to design and analyze the survey data are illustrated.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.223-229
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• 2002

For the research of the natural marine antioxidant, several bacteria were isolated from the coast of jin-Hae in Korea. Among the marine bacteria studied, strain HJ-14, a gram-negative, motile, strait rod, aerobic, and $Na^{+}$ required bacterium showed high activity of 1,1-diphenyl-2-picrylhydrazyl radical scav- enging. The morphological, physiological, and biochemical characteristics of the strain HJ-14 were similar to those of the Alteromonas macleodii ATCC $27126^{T}$ . Thus, it was tentatively identified as Alteromonas sp. HJ-14. The compositions of major fatty acids in cell membrane of Alteromonas sp. HJ-14 were $C_{ 14:0}$ , $ C_{15:0}$ , $C_{16:0}$ and $C_{17:1}$ $_{w8c}$ , which also suggest that it is affiliated with Alteromonas sp. The optimum culture conditions for production of antioxidant materials with Alteromonas sp. HJ-14 were at $25$~$37^{\circ}C$ and pH 6~8. The optimum conditions for the production of antioxidant for carbon, inorganic nitrogen, and sodium chloride sources were 2.5%(w/v) dextrin, 0.5%(w/v) ammonium sulfate, and 2~6%(w/v) sodium chloride, respectively. The hydroxyl radical scavenging ability of Alteromonas sp. HJ-14 broth was 90.03%, which is higher than ascor-bic acid(83.28%) and lower than butylated hydroxyanisole(95.46%) and $\alpha$-tocopherol(97.17%).

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.3
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• pp.28-39
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• 2010

In this paper, a new method to estimate MU (motor unit) location in the short head of BIC (biceps brachii) muscle using surface EMG (electromyogram) is proposed. The SMUAP (single motor unit action potential) is generated from a MU located at certain depth from the skin surface. The depth is referred as MU location. For estimating muscle force precisely, the information of the MU location is required. The reference SMUAPs are simulated based on anatomical structure of human muscle, and compared with acquired real EMG signals using 3-channel surface EMG electrode. The proposed method was compared with the results of previous researchers and verified its accuracy by computer simulation. From the simulation result in case of the MU located in 8[mm], the average estimation error of proposed method was 0.01[mm]. But the average estimation error of Roeleveld's method was 2.33[mm] and Akazawa's method was 1.70[mm]. Therefore the proposed method was more accurate than the methods of previous researchers.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.203-211
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• 2015

Purpose: The purpose of this study was to investigate the reosseointegration periods when the rough surface implants, which had complete bone-implant ankylosis, suddenly losed the osseointegration. Materials and Methods: The implants with RBM surface treatment were inserted into both tibias of 23 rabbits. Two implants were submerged into each side. After six weeks, the primary removal torque was measured by Digital torque gauge, and then the implants were replaced and submerged to estimate the level of reosseointegration. After assigned healing periods for each group, the removal torque was measured again. BIC (Bone-Implant contact, %) ratio was measured through histomorphometric analysis.Paired t-test was processed by SPSS 14.0. One-way ANOVA and Tukey's post-hoc test was processed to analyze statistically significant differences among the groups. Results: In comparison with the primary removal torque, the secondary removal torque was increased after 11 days and significantly increased from 2 weeks. In fluorochrome labeling, the origin of mineralization was observed after 7 days, which showed as fluorescent bands around the bone-implant interfaces. After 11 days, the bone formation was apparent, and it is increased continuously with the passage of the time. Conclusion: In 11 days after the implant replacement, the secondary removal torque was almost as same as the primary value, and was significantly higher from 2 weeks. The mineralized shapes were observed in 7 days after the implant replacement, and then the bone formation appeared visibly in 11 days.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.6
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• pp.481-491
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• 2005

Purpose: The aim of the present study is to evaluate the effect of autogenous bone and allograft material coverd with a bioresorbable membrane on bone regeneration after a simultaneous installation of implant. Materials and methods: Twelve healthy rabbits, weighing about $3{\sim}4$ kg, were used in this experiment. Following impalnt(with 3.25 mm diameter and 8 mm length) site preparation by surgical protocol of $Oraltronics^{(R)}$, artificial bony defect, 5mm sized in height and depth, was created on femoral condyle using trephine drill(with 5 mm diameter and 5 mm length). Then implant was inserted. In the experimental group A, the bony defect was filled with autogenous particulated bone and coverd with $Lyoplant^{(R)}$ resorbable membrane. In the experimental group B, the bony defect was filled with allograft material(Orthoblast $II^{(R)}$) containing demineralized bone matrix and covered with $Lyoplant^{(R)}$. In the control group, without any graft materials, the bony defect was covered with $Lyoplant^{(R)}$. The experimental group A and B were divided into each 9 cases and control group into 3 cases. The experimental animals were sacrificed at 3, 6 and 8 weeks after surgery and block specimens were obtained. With histologic and histomorphometric analysis, we observed the histologic changes of the cells and bone formation after H-E staining and then, measured BIC and bone density with KAPPA Image $Base^{(R)}$ system. Results: As a result of this experiment, bone formation and active remodeling process were examined in all experimental groups and the control. But, the ability of bone formation of the experimental group A was somewhat better than any other groups. Especially bone to-implant contact fraction ranged from 12.7% to 43.45% in the autogenous bone group and from 9.02% to 29.83% in DBM group, at 3 and 8 weeks. But, bone density ranged from 15.67% to 23.17% in the autogenous bone group and from 25.95% to 46.06% in DBM group at 3 and 6 weeks, respectively. Although the bone density of DBM group was better than that of autogenous bone group at 3 and 6weeks, the latter was better than the former at 8 weeks, 54.3% and 45.1%, respectively. Therefore these results showed that DBM enhanced the density of newly formed bone at least initially.

• Journal of Agricultural Extension & Community Development
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• v.20 no.1
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• pp.1-39
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• 2013

The Cooperatives Act was enacted. This enabled people to establish easily cooperatives at various fields. A cooperative is an important vehicle for rural community development. Therefore, the enactment of the Cooperatives Act can be a significant chance for rural policy. The Cooperatives Act have made three significant changes. First, cooperatives can start businesses at all the fields except for financial and insurance business. Second, requisites for people to establish cooperatives have been alleviated exceptionaly. Third, the Cooperatives Act introduced a new cooperative organization, social cooperative which aims to serve the socially excluded class. The self-help approach places rural community members at the core of a development process with two goals: to improve the quality of life within the community and to facilitate the community's capacity building. Community cooperatives contribute to accomplish those goals. One of the roles for cooperatives is to provide products and services at competitive prices. Providing a good or service at a competitive price bcomes increasingly important in some rural communities declines. Cooperative development processes have bic impacts on the ablility of community members to increase human asset and social capital. We conducted a survey targeting rural community businesses to grasp inclinations toward establishing cooperatives. The Cooperatives Act has gained low level of recognition. But so many community businesses wanted to establish cooperatives. This means there is a possibility for many community businesses to establish cooperatives without sufficient understanding. We suggested some policy issues for coping with this situation, as followings. First, the governments should provides rural community residents with opportunities to learn about cooperatives. Second, the current legal systems and regulations about business and social service should be reviewed to do away with the possible discrimination between the new cooperatives and the other forms of incoporation. Third, the cooperation of cooperatives should be encouraged and facilitated in rural communities.

• Journal of Global Scholars of Marketing Science
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• v.17 no.3
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• pp.1-19
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• 2007

1. Purpose Rural tourism is made by individuals with different characteristics, needs and wants. It is important to have information on the characteristics and preferences of the consumers of the different types of existing rural accommodation. The stud aims to identify the determinants of consumer preference by type of accommodations. 2. Methodology 2.1 Sample Data were collected from 1000 people by telephone survey with three-stage stratified random sampling in seven metropolitan areas in Korea. Respondents were chosen by sampling internal on telephone book published in 2006. We surveyed from four to ten-thirty 0'clock afternoon so as to systematic sampling considering respondents' life cycle. 2.2 Two-step cluster Analysis Our study is accomplished through the use of a two-step cluster method to classify the accommodation in a reduced number of groups, so that each group constitutes a type. This method had been suggested as appropriate in clustering large data sets with mixed attributes. The method is based on a distance measure that enables data with both continuous and categorical attributes to be clustered. This is derived from a probabilistic model in which the distance between two clusters in equivalent to the decrease in log-likelihood function as a result of merging. 2.3 Multinomial Logit Analysis The estimation of a Multionmial Logit model determines the characteristics of tourist who is most likely to opt for each type of accommodation. The Multinomial Logit model constitutes an appropriate framework to explore and explain choice process where the choice set consists of more than two alternatives. Due to its ease and quick estimation of parameters, the Multinomial Logit model has been used for many empirical studies of choice in tourism. 3. Findings The auto-clustering algorithm indicated that a five-cluster solution was the best model, because it minimized the BIC value and the change in them between adjacent numbers of clusters. The accommodation establishments can be classified into five types: Traditional House, Typical Farmhouse, Farmstay house for group Tour, Log Cabin for Family, and Log Cabin for Individuals. Group 1 (Traditional House) includes mainly the large accommodation establishments, i.e. those with ondoll style room providing meals and one shower room on family tourist, of original construction style house. Group 2 (Typical Farmhouse) encompasses accommodation establishments of Ondoll rooms and each bathroom providing meals. It includes, in other words, the tourist accommodations Known as "rural houses." Group 3 (Farmstay House for Group) has accommodation establishments of Ondoll rooms not providing meals and self cooking facilities, large room size over five persons. Group 4 (Log Cabin for Family) includes mainly the popular accommodation establishments, i.e. those with Ondoll style room with on shower room on family tourist, of western styled log house. While the accommodations in this group are not defined as regards type of construction, the group does include all the original Korean style construction, Finally, group 5 (Log Cabin for Individuals)includes those accommodations that are bedroom western styled wooden house with each bathroom. First Multinomial Logit model is estimated including all the explicative variables considered and taking accommodation group 2 as base alternative. The results show that the variables and the estimated values of the parameters for the model giving the probability of each of the five different types of accommodation available in rural tourism village in Korea, according to the socio-economic and trip related characteristics of the individuals. An initial observation of the analysis reveals that none of variables income, the number of journey, distance, and residential style of house is explicative in the choice of rural accommodation. The age and accompany variables are significant for accommodation establishment of group 1. The education and rural residential experience variables are significant for accommodation establishment of groups 4 and 5. The expenditure and marital status variables are significant for accommodation establishment of group 4. The gender and occupation variable are significant for accommodation establishment of group 3. The loyalty variable is significant for accommodation establishment of groups 3 and 4. The study indicates that significant differences exist among the individuals who choose each type of accommodation at a destination. From this investigation is evident that several profiles of tourists can be attracted by a rural destination according to the types of existing accommodations at this destination. Besides, the tourist profiles may be used as the basis for investment policy and promotion for each type of accommodation, making use in each case of the variables that indicate a greater likelihood of influencing the tourist choice of accommodation.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.318-326
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• 2007

Characteristics of organophoshhorus pesticides (OPs) distribution were investigated in Shingu Reservoir, as a shallow eutrophic agriculture reservoir in Korea. In August 2006, IBP, DDVP and dyfonate were detected in the water column of Singu Reservoir, ranging from 1340.7 to 16030.1 ng $L^{-1}$, 58.7 to 127.6 ng $L^{-1}$ and N.D. to 20.3 ng $L^{-1}$, respectively, However, in September 2006, mevinfos, ethoprofos, phorate, chlorfenvinfos, and methidathion were also found in addition to IBP (202.5${\sim}$213.2 ng $L^{-1}$), DDVP (100.7${\sim}$340.6 ng $L^{-1}$) and dyfonate (N.D.${\sim}$25.0 ng $L^{-1})$. Maximum concentrations of OPs were observed at the middle depth in August, which might be related with photo-oxidation. On the other hand, IBP and DDVP among the OPs were detected in suspended particles, suggesting the relatively active adsorption reactivity. The composition of OPs varied temporally on account of the influence of inflow water from its surrounding areas. In the present study, the observed OPs concentrations seem to be not acute toBic levels to aquatic organisms in Shingu Reservoir, considering the standard monitoring levels of U.S. Environmental Protection Agency and Japan Ministry of Environment.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.445-456
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• 2009

Statement of problem: Many studies have been conducted to improve the primary stability of implants by providing bioactive surfaces via surface treatments. Increase of surface roughness may increase osteoblast activity and promote stronger bonding between bone and implant surface and it has been reported that bioactive surface or titanium can be obtained through alkali and heat treatment. Purpose: The purpose of this study was to evaluate the stability of alkali and heat treated implants via histomorphometric analysis. Material and methods: Specimens were divided into three groups; group 1 was the control group with machined surface, the other groups were treated for 24 hours in 5 M NaOH solution and heat treated for 1 hour at $600^{\circ}C$ in the atmosphere (group 2) and vacuum (group 3) conditions respectively. Surface characteristics were analyzed and fixtures were implanted into rabbits. The specimens were histologically and histomorphometrically compared according to healing periods and change in bone composition were analyzed with EPMA (Electron Probe Micro Analyzer). Results: 1. Groups treated with alkali and heat showed increase of oxidization layer and Na ions. Groups 2 which was heat treated in atmosphere showed significant increase of surface roughness (P<.05). 2. Histomorphometric analysis showed significant increase in BIC (bone to implant contact) according to increase in healing period and there was significant increases in groups 2 and 3 (P<.05). 3. BA(bone area) ratio showed similar results as contact ratio, but according to statistical analysis there was significant increase according to increase in healing period in group 2 only (P<.05). 4. EPMA analysis revealed no difference in gradation of bone composition of K, P, Ca, Ti in surrounding bone of implants according to healing periods but groups 2 and 3 showed increase of Ca and P in the initial stages. Conclusion: From the results above, it can be considered that alkali and heat treated implants in the atmosphere have advantages in osseointegration in early stages and may decrease the time interval between implantation and functional adaptation.