• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.27-43
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• 2020

Purpose - This study explores the impact of the real estate industry on related industries for the perspective of Chinese steel companies. Design/methodology/approach - The impact of housing prices on the 41 listed steel companies' performance was analyzed by using the panel data model. We used two kinds of housing price indexes that are set in the panel data models to estimate the range of the real estate market, driving the performance growth of steel listed companies. Moreover, the net profit of steel companies is used as the dependent variable. To test the stability of the model, ROA used as a dependent variable for the robustness test. Also, to avoid the time trend of housing prices, this paper selects the growth rate of housing prices as the primary research variable. After Fisher-type testings, there is no unit root problem in both independent and dependent variables. Findings - The results indicated that the rise in the housing price has a positive influence on the steel company performance. When the housing price increases by 1%, the net profit of steel enterprises will increase by 5 to 20 million yuan. Research implications or Originality - In this paper, empirical data at the micro-level and panel model are used to quantify China's real estate industry's driving effect on the iron and steel industry, providing evidence from the microdata level. It helps us to understand further the status and role of China's real estate industry in the economic structure.

• Journal of Chest Surgery
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• v.46 no.6
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• pp.449-456
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• 2013

Background: Tumor recurrence is the most common cause of treatment failure, even after complete resection of early-stage non-small cell lung cancer (NSCLC). In this study, we investigated the prognosis of patients with early recurrence in order to identify independent risk factors related to early recurrence. Methods: Between February 1995 and December 2012, 242 patients who underwent surgical resection for stage I NSCLC at Dong-A University Hospital were reviewed. The factors predicting overall survival (OS) and early recurrence were investigated. We also investigated the relationship between the patterns and period of recurrence and clinicopathological factors. Results: For patients with stage IA and IB NSCLC, the 5-year OS rate was 75.7% and 57.3% (p=0.006), respectively. A multivariate Cox proportional hazards model demonstrated that gender (p=0.004), comorbidity number (p=0.038), resection type (p=0.002), and tumor size (p=0.022) were the statistically significant predictors of OS. Moreover, the multivariate analysis revealed that smoking history (p=0.023) and histologic grade (p=0.012) were the independent predictors of early recurrence. Additionally, only histologic grade (poor differentiation) was found to be significantly associated with a higher frequency of distant metastasis; there was no relationship between the patterns and period of recurrence and clinicopathological factors. Conclusion: The present study demonstrated that smoking history and histologic grade were independent prognostic factors for early recurrence within two years in patients with early-stage NSCLC. Patients with these predictive factors may be good candidates for adjuvant therapy.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.6
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• pp.805-814
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• 2013

This paper proposes a robust hand segmentation method using view-invariant characteristic of a wrist-mounted camera, and deals with a hand shape recognition system based on segmented hand information. We actively utilize the advantage of the proposed camera device that provides view-invariant images physically, and segment hand region using a Bayesian rule based on adaptive histograms. We construct HSV histograms from RGB histograms, and update HSV histograms using hand region information from a current image. We also propose a user adaptation method by which hand models gradually approach user-dependent models from user-independent models as the user uses the system. The proposed method was evaluated using 16 Korean manual alphabet, and we obtained increases of 27.91% in recognition success rate.

• Journal of Preventive Medicine and Public Health
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• v.11 no.1
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• pp.24-30
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• 1978

This study was designed to analyse effects of Family Health Workers' activities on the performance of a child immunization program as part of the evaluative research in the community health demonstration project in Kang Wha. Frequent shortcomings of evaluative research are problems in setting evaluative indices, difficulties in interpreting influences of socioeconomic changes due to lack of control and failure of demonstrating association between activity input and program performance. Specific objectives of this study was to improve the frequent shortcoming of evaluative research by isolating the effects of Family Health Workers' activities on the performance of the program through controlling other variables which also influenced the program performance. The target population consisted of 1240 children who were born between Jan. 1971 and Dec. 1975 in Sunwon Myun, and Naega Myun in Kwang Wha Gun, Kyonggi Province. The data were collected in part through 20 Family Health Workers who interviewed the mothers of these children in their villages during Nov. 1977. Part of the data were obtained by summarizing Family Health Workers daily activity records. All data were grouped for each birth cohort according to the 20 villages. Dependent variable of the model is the measle immuinization rate of each village and the independent variables are characteristics of baby, mother, household, travel time to the health subcenter, to Kang Wha Town, and the mean member of visits to the household by Family Health Workers as well as their other related activities and the year of birth of children according to village. The model was analysed by stepwise multiple regression technique. The summarized results show that overall $R^2$ were 39.3% and mean number of Family Health Worker household visits, mean age of mother and mean economic status were significant variables in explaining the immunization rate. Therefore Family Health Workers' activities are one of the significant variables in influencing the increased immunization rate of children in villages of the project area.

• The Korean Journal of Applied Statistics
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• v.20 no.3
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• pp.423-440
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• 2007

Although various models have been developed to establish the enterprise credit scoring, no model has utilized the enterprise human resource so far. The purpose of this study was to build an enterprise credit scoring model using enterprise human resource factors. The data to measure the enterprise credit score were made by the first-year research material of HCCP was used to investigate the enterprise human resource and 2004 Credit Rating Score generated from KIS-Credit Scoring Model. The independent variables were chosen among questionnaires of HCCP based on Mclagan(1989)'s HR wheel model, and the credit score of Korean Information Service was used for the dependent variables. The statistical method used for data analysis was logistic regression. As a result of constructing a model, 22 variables were selected. To see these specifically by each large area, 6 variables in human resource development(HRD) area, 15 in human resource management(HRM) area, and 1 in the other area were chosen. As a consequence of 10 fold cross validation, misclassification rate and G-mean were 30.81 and 68.27 respectively. Decile having the highest response rate was bigger than the one having the lowest response rate by 6.08 times, and had a tendency to decrease. Therefore, the result of study showed that the proposed model was appropriate to measure enterprise credit score using enterprise human resource variables.

• Journal of the Korean GEO-environmental Society
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• v.9 no.7
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• pp.73-85
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• 2008

320 national groundwater monitoring stations have been constructed since 1995 and groundwater levels are measured automatically 4 times a day at each well. It has a difficulty to estimate an average recharge rate of watershed using the recharge rate of the monitoring site because of the lack of its representative on converting a point recharge rate into a spatial one. In this study, the relations between site characteristics (topography, hydraulics, geology, facilities, etc.) and recharge rates of 223 monitoring sites, which were selected using cluster analysis, were analyzed using statistical methods, and finally, regression models were constructed for a recharge rate estimation of non-measured areas. The independent variables for these simple regression models, 1) width of adjacent stream, 2) distance to the nearest stream, 3) topographic slope, and 4) rock type, are proposed using analysis of variance. These models have lots of advantages such as an easy data collection from topographic and geologic maps, a few input variables, and also simplicity in use. Suitability analysis from the comparison between estimation values and original ones at monitoring sites shows that these models are useful for a groundwater recharge estimation.

• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.31-36
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• 2010

Rising interest rates positively affect investment in construction, while falling interest rates affect it negatively. In other words, the interest rate is one of the most critical factors affecting the construction sector. The purpose of this research is to analyze the relationship between the annual interest rate and construction contracts, and to present a model for quantitatively forecasting the economic performance of the construction sector. Based on the statistical data of interest rate changes for 19 years (from 1991 to 2009), this research induces an equation through regression analysis that incorporates interest rate and construction contract amounts as independent and dependent variables, respectively. The result of the analysis shows that, in the building and private sector, the interest rates are closely related to, with a correlation coefficient as high as 0.85. It was also indicated that the contract amounts of private and building sectors may increase quite rapidly in 2012.

• Journal of Biosystems Engineering
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• v.34 no.2
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• pp.114-119
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• 2009

Field test was conducted to investigate primary factors reducing rapeseed harvesting using a reciprocating cutter-bar of combine. The results showed that the correlation between crop moisture content and yield loss had a U-type, which indicated that the yield reduction increased at too high and too low crop moisture contents. The proper ranges of crop moisture contents were 27${\sim}$35%, 21${\sim}$56%, and 62${\sim}$73% in case of grain, pod and stem, respectively. Crop moisture content was negatively correlated with header loss, but positively correlated with threshing loss. In contrary, stem moisture content showed positive correlations with total loss, threshing loss and separation loss. Working speed was positively correlated with header loss. Total flow rate, pod flow rate and stem flow rate were highly correlated with threshing loss and separation loss. However, grain flow rate did not show any correlation with total loss. According to the principal component analysis, two principal components were derived as components with eigenvalues greater than 1.0. The contribution rates of the first and the second components were 52.7% and 38.9%, which accounted for 91.6% of total variance. As a contributive factor influencing total loss of rapeseed mechanical harvesting, a crop moisture content factor was greater than a crop flow rate factor. The stepwise multiple regression analysis for total loss was conducted using crop moisture content factor, crop flow rate factor and coefficient. However, the model did not show any correlation among independent and dependent factors ($R^2$=0.060).

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.63-72
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• 2007

The purpose of this study is to develop a traffic characteristic analysis, a correlation analysis with the variables of traffic characteristics, and accident estimation models while recognizing the seriousness of the traffic accidents. The analyses deal with the 181 4-legged signalized intersections that accounted for 1,183 out of 3,115 accidents in Cheongju in 2004. After measuring ADT, intersection area, average lane width, elevation, and other items as independent variables and the number of traffic accidents, the traffic accident rate (accidents per million entering vehicles) and equivalent property damage only (EPDO) figures as dependent variables which are estimated as influencing signalized intersection accidents, the estimation models are developed using correlation analysis and multiple regression analysis. In the analysis of the number of traffic accidents, the model indicates an $R^2$ of 0.612, and five independent variables are taken as significant factors. In the analysis of traffic accident rates, the model indicates an $R^2$ of 0.304 and five significant factors, including intersection area and ADT. Also, for the analysis or the EPDO numbers, which coincides with understanding the seriousness of the traffic accidents and the traffic characteristic analysis, the model indicates an $R^2$ of 0.559, and four independent variables (ADT, main street average lane width, elevation, and speed limit) as significant factors.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.723-730
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• 2017

The batch experiments by response surface methodology (RSM) have been applied to investigate the influences of operating parameters such as temperature, initial concentration, contact time and adsorbent dosage on 2,4-dichlorophenol (2,4-DCP) adsorption with an activated carbon prepared from waste citrus peel (WCAC). Regression equation formulated for the 2,4-DCP adsorption was represented as a function of response variables. Adequacy of the model was tested by the correlation between experimental and predicted values of the response. A fairly high value of $R^2$ (0.9921) indicated that most of the data variation was explained by the regression model. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. These results showed that the model used to fit response variables was significant and adequate to represent the relationship between the response and the independent variables. The kinetics and isotherm experiment data can be well described with the pseudo-second order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of 2,4-DCP on WCAC calculated from the Langmuir isotherm model was 345.49 mg/g. The rate controlling mechanism study revealed that film diffusion and intraparticle diffusion were simultaneously occurring during the adsorption process. The thermodynamic parameters indicated that the adsorption reaction of 2,4-DCP on WCAC was an endothermic and spontaneous process.