• The Korean Journal of Applied Statistics
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• v.27 no.3
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• pp.501-512
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• 2014

Modified cut-off sampling is widely used for highly skewed data. A serious drawback of modified cut-off sampling is the difficulty of adjustment of non-response in take-all stratum. Therefore, solutions of the problems of non-response in take-all stratum have been studied in various ways such as substitute of samples, imputation or re-weight method. In this paper, a new cut-off point based on minimizing MSE being used in exponential and power functions is suggested and it can be reduced the number of take-all stratum. We also investigate another cut-off point determination method with underlying distributions such as truncated log-normal and truncated gamma distributions. Finally we suggest the optimal cut-off point which has a minimum of take-all stratum size among suggested methods. Simulation studies are performed and Labor Survey data and simulated data are used for the case study.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.245-250
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• 2014

The purpose of this study is to introduce a empirical study of using Taguchi Method for the Entrepreneurial Orientation and Financial Performance. In this study, three factors of Entrepreneurial Orientation, innovation, pro-activity and risk taking, are used of the control factors and an element, period of establishment, is chosen as a noise factor. In order to carry out this research, we obtained 200 survey sheets and performed the reliability and validity analysis of the questionnaires and then the experiment was conducted by Taguchi's experimental design. To improve Financial Performance under the noise factor of period of establishment, optimal condition are as follows; the two factors of Entrepreneurial Orientation, innovation, pro-activity should be maintained to a high level. Also, other factor, risk taking should be performed as the level that the company has maintained. Through this paper, we find out that Taguchi method is applicable for analysis of questionnaire.

• Journal of the Korean Dietetic Association
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• v.17 no.3
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• pp.313-326
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• 2011

This study was performed to investigate the relationship between milk and milk product consumption and dietary nutrient intake among Korean adolescents. Questionnaire survey and 3-day diet survey using the food record method were completed by a total of 664 subjects. Subjects were divided into three groups, Q1 (low group), Q2 (middle group), and Q3 (high group), according to dairy equivalent of calcium. Dairy equivalent of calcium was determined by the amount of calcium eaten from milk and milk products by individual subjects. As a result, the ratio of school milk service was higher in Q3 (P<0.001). The most frequent answer about the reason for consuming milk and milk products was 'to be taller' followed by 'good taste' and 'health promotion'. Preference for all types of milk such as white-, enriched-, and flavored-milk was higher in Q3 followed by Q2>Q1 (P<0.05). Ratio of mean daily dietary nutrient intakes of dietary fiber, vitamin C, folate, and calcium to RNI was lower than 2/3 for all of the groups. These mean daily dietary nutrient intakes were significantly higher in Q3 (P<0.05), and in particular, mean daily dietary calcium intake, which was the lowest nutrient consumed by Korean adolescents, was also the highest in Q3 followed by Q2>Q1 (P<0.05). The above results suggest that the school milk program is very helpful in encouraging adolescents to consume milk and milk products and consequently ensure their optimal nutrition. Therefore, we should try to encourage adolescents to participate in the school milk program more actively through nutritional education and government policy.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.13 no.3
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• pp.419-427
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• 2006

Purpose: This descriptive survey was done to assess how rural women with osteoarthritis perceive their symptoms, what are their treatment preferences, and how they manage their illness. Method: Individual interviews were carried out with 205 women with osteoarthritis living in rural areas. Structured questionnaires were used and the interviewers were 7 trained research assistants. Descriptive statistics were used for data analysis with SPSS win 11.5 program. Results: Of the respondents, 68.8% were overweight and 15.1% were obese, 86.9% reported pain in the knees, low back, and shoulders and the average pain score was 66.06. Those knowing the exact diagnosis accounted for 73.7% of the respondents but only 49.7% reported receiving medical treatments, and 40.2% who received treatment adhered to their prescription. Folk medicines were used by 14.1% of the respondents, but 65.2% among them reported that folk medicines were not effective. Exercise 2.03 times per week was reported by 17.1% of the respondents and 48.6% reported preferring to walk. Conclusion: Women with osteoarthritis in rural areas need a rehabilitative care program focused on exercise. The community health care system in the rural area should deliver optimal health care for this population. The results of this study can be used as a basis for planning intervention programs for women with osteoarthritis in the rural area.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.2
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• pp.1-9
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• 2000

The purpose of this study is to examine influence of interior landscape in commercial spaces on the management benefit. In the course of this study, objects of survey were selected from interior landscaping specialist, manager and consumer who had experiences to visit to the hotel, bank, department store and restaurant. The main method of data collection was interview, questions and gathering materials. The cronbach's alphas program was used to measure the reliability of likert scales. The analysis program was applied a statistical methods. The results of this study can be summarized as follows: The factors considered by consumer who visits to the commercial space are design, interior landscape, traffic, parking capacity, cleanness, price, kindness of employee and event. Factors concerned with the product include branch size, traffic, parking capacity, kindness of employee. Factors concerned with facilities include branch size, traffic, parking capacity, kindness of employee. Major factors of those effects to management benefit are accessibility, time of stay, sales, efficiency of space, attractiveness and difference. In conclusion, overlap style gets the highest degree of satisfaction among total factors. Results of the survey show that factors which improve sales are overlap style and planter type. Among four commercial spaces, hotel is most effected by interior landscape. To enhance the sales of hotel, further study of interior landscape about hotel necessary. For bank and restaurant, further study of economic planter type and style is necessary. For department store, optimal use of spaces and case of maintenance are necessary.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.8
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• pp.14-20
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• 2009

In this paper, the time-varying failure rate to consider climate effect was extracted. Even if the same kind of equipments is estimated for extracting the time-varying failure rate, the failure rates could be different depending on external effect such as climate. With the consequence, the failure rate extracted to consider the climate effect is necessary for using the failure rate on the optimal investment plan or asset management, To consider the characteristic of climate effects(Classified into 5 categories, heavy rain, thunderbolt, strong wind, tidal waves, no character), the survey of officers charging the operation of equipment in KEPCO branch office was done. With this consequence, this paper suggest the failure rate extraction method to consider the climate effect analyzed by the survey.

• Archives of design research
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• v.20 no.3 s.71
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• pp.345-354
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• 2007

Sometimes characterized graphic map rather than realistic graphic map can help users to understand information more easily. This paper tried to reveal the relation between the methodology to create outline on the map using caricature automatic algorism and level of human cognition. Caricature algorism such as exaggeration transformation algorism, joint transformation algorism and simplification algorism were used to create outline on the map. In order to apply exaggeration transformation algorism and joint transformation algorism, the method to create average form of the object were developed. We survey how users recognize the similarity of the characterized map with the real map when realistic map is simplified by certain value of simplification rate and transformed into certain value of exaggeration rate or joint transformation rate. We also survey how users recognize the similarity differently according to the scale of the map. As a result of this study, the method to calculate the optimal data is developed for users to recognize caricatured map effectively by shifting scale. This data can be used as basic data, when map developers create outline of map with programming code on computer

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3561-3565
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• 2011

A rapid and inexpensive method was developed for the determination of trace silver in geological samples by using sulfhydryl cotton coupled with ICP-MS. The interferences such as $^{90}Zr$, $^{92}Mo$ and $^{93}Nb$ on silver were investigated in detail. Sulfhydryl cotton was found to be an effective adsorbent for separation of interferences for Ag in the solutions. Excellent agreements with the certified values were obtained for all the certified reference materials. The memory effects of Ag by ICP-MS were examined by using different agents, including water, nitric acid, and HCl-thiourea to all standards/samples. The agents also acted as cleansing solutions. A combination of HCl with thiourea gave the minimum memory effect. For comparison of results, a proposed Chinese Geology Survey procedure DC-ARC-AES and a direct determination pretreatment method of ICP-MS (water bath- auqa regia digestion) were studied. Under optimal conditions, the detection limits of our method for $^{107}Ag$ and $^{109}Ag$ were 1.2 ng/g and 1.3 ng/g, which offered much better accuracy for some difficult analysis geological samples such as GBW07604, GBW07605.

• Journal of the Economic Geographical Society of Korea
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• v.21 no.2
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• pp.107-118
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• 2018

Due to the rapid economic development, traffic congestion has become a dire concern in Beijing, China. Levying a congestion toll is seen as the most effective solution to the problem. Building a congestion pricing model is a crucial step in implementing a workable toll scheme. Unlike previous attempts, this study not only covers the theoretical discussion but also considers three practical issues: the speed-density relationship, the value of travel time savings, and the determination of optimal traffic volume. We estimate the speed-density relationship by regression models and the value of travel time saved through survey results. We further suggest a way through which the government could identify the optimal traffic flow by a series of trial-and-errors, without the knowledge of exact road demand structure. Finally, a practical tolling scheme is proposed for Beijing's second ring road along with some policy recommendations.

• Journal of Korean Society of Transportation
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• v.20 no.4
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• pp.83-93
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• 2002

To improve the performance of estimation, the research that uses additional information addition to traffic count and target OD with additional survey cost have been studied. The purpose of this paper is to improve the performance of OD estimation by reducing the feasible solutions with cost-efficiently additional information addition to traffic counts and target OD. For this purpose, we Propose the OD estimation method with sample link use proportion as additional information. That is, we obtain the relationship between OD trip and link flow from sample link use proportion that is high reliable information with roadside survey, not from the traffic assignment of target OD. Therefore, this paper proposes OD estimation algorithm in which the conservation of link flow rule under the path-based non-equilibrium traffic assignment concept. Numerical result with test network shows that it is possible to improve the performance of OD estimation where the precision of additional data is low, since sample link use Proportion represented the information showing the relationship between OD trip and link flow. And this method shows the robust performance of estimation where traffic count or OD trip be changed, since this method did not largely affected by the error of target OD and the one of traffic count. In addition to, we also propose that we must set the level of data precision by considering the level of other information precision, because "precision problem between information" is generated when we use additional information like sample link use proportion etc. And we Propose that the method using traffic count as basic information must obtain the link flow to certain level in order to high the applicability of additional information. Finally, we propose that additional information on link have a optimal counting location problem. Expecially by Precision of information side it is possible that optimal survey location problem of sample link use proportion have a much impact on the performance of OD estimation rather than optimal counting location problem of link flow.