• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1531-1541
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• 2013

This paper proposes a new method of VaR forecasting using the conditional autoregressive VaR (CAViaR) models and information criteria. Instead of using a single CAViaR model, we propose to utilize several candidate CAViaR models during a forecasting period. By adopting the Akaike and Bayesian information criteria for quantile regression, we can update not only parameter estimates but also the CAViaR specifications. We also propose extended CAViaR models with a constant location parameter. An empirical study is provided to examine the performance of the proposed method. The results suggest that our method shows more stable performance than those using a single specification.

• Journal of Trauma and Injury
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• v.21 no.1
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• pp.15-21
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• 2008

Purpose: National Emergency X-Radiography Utilization Study (NEXUS) criteria and the Canadian Cervical Spine rule (CCR) are commonly used in cervical trauma patients to determine whether a plain cervical X-ray should be performed. However, plain cervical X-rays are so inaccurate that cervical spine computed tomography (CT) is often considered as a screening test. We studied the usefulness of the NEXUS criteria and the CCR for determining the need for a CT evaluation in the emergency department (ED). Methods: This prospective observational study was conducted from January 2007 to March 2008. Plain X-ray and CT scans of the cervical spine were performed on blunt trauma patients with neck pain. The relevancy of CT was examined using the NEXUS criteria and the CCR. Sensitivity, specificity, positive predicted value, and negative predicted value analyses were performed to diagnose the cervical spine injury. Results: During the study period, 284 patients were enrolled in this study. The sensitivity, specificity, positive predicted value, and negative predicted value of the NEXUS criteria were 87.5%, 1.1%, 5.0%, and 60.0% respectively, while those of the CCR were 87.5%, 8.2%, 5.3%, and 91.6%. There were two missed fracture cases when the NEXUS criteria and the CCR were applied independently, however, no cases were missed when both were applied. Conclusion: This study suggests the NEXUS and the CCR in combination can be used as a guide to CT evaluation for cervical spine injury in the ED.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.446-455
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• 2018

With respect to the quantity, quality and social value of forest jobs, we have developed three major criteria and 11 indicators for evaluating decent forest jobs. The importance and weighted value of the criteria and indicators were investigated through a survey which was conducted on 50 experts involved in Governmental Forest Job Committee, academic and different groups of communities. The 35 experts responded to the survey chose the 'job creation potential' as the most important criterion, and they recognized the 'job quality' has a relatively higher importance than the 'social contribution'. The survey results showed that 'political will' and 'job security' have the highest weighted values among indicators while 'wage level' has the lowest value. The developed criteria and indicators are able to be used as a means of evaluating degree of decent forest jobs for both new and existing jobs.

• Journal of the Korean Society of Safety
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• v.8 no.3
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• pp.34-43
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• 1993

This paper presents a study on the characteristics and safety criteria for human body in ELF (Extremely Low Frequency : 50-60Hz) electric and magnetic fields. Many researches for ELF electric and magnetic fields, which are developed in the past, are studied and analyzed In this paper. In order to estabilish the safety criteria for human body in the field, the field intensity, induced current and voltage are calculated by the electrostatic field approach which is far simpler than the electromagnetic field one based on Maxwell equation. The method is applied to the 345 KV transmission line system In operation and 765 KV system under consideration. According to the results, the maximum value of field intensity, 6.8627KV/m, is evaluated at the location which is 14m away from transmission line. As the safety criteria value by the abroad researches asserting that the human can detect the Induced current in 6KV/m and above, 5KV/m and 7KV/m are recommended at residence area and nonresidence area, respectively.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.116-127
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• 2004

The objectives of this study are to build up the concept of Environment-Oriented Land Suitability Assessment(EOLSA) and to develop the EOLSA mapping system by applying the EOLSA criteria to the case study area. In order to draw out the EOLSA critera, this study adopted the Delphi method including the experts' awareness survey to urban planners as well as environmental researchers in May and June 2001. As a result, the concept of EPLSA was defined as a process of land use planning to scientifically assess the physical and environmental value of land and to classify conservation aptitude into several grades for the sustainable management of environmental resources. With an outcome of applying the EOLSA criteria with five degrees to the Seoul Metropolitan Area (SMA), Grade I, indicating the highest conservation value, accounted for 57.76% of the SMA. Then, Grade II reached up to 15.06%, Grade III 3.12%, Grade IV 15.92%, and Grade V, the lowest conservation value, 7.99% respectively. And also, the case analysis showed that the share of Grade I area was the highest in Gapyong county and Yangpyong county, Pochon county, Yeonchon county, Yongin city in the order and the lowest in Kwangmyong city, Osan city, Kunpo city, Kuri city, and Buchon city.

• Journal of the Korean Regional Science Association
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• v.11 no.1
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• pp.1-20
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• 1995

This paper studies the comparative advantage of competitive and specialized regional industries which are manufacturing, wholesale and retail trade, servies in the metropolitan area-Seoul, Inchun, Kyunggi-do of Korea, For the analysis of industries, the coefficient of specialization, the indices of competitiveness of labor and value-added, the growth rate are simultaneously examined under the criteria of the number of workers, value of shipment, value-added, This comperative synthetic analysis is different from the traditional approaches. This paper shows that the perfectly competitive advantage of specialized industries satisfying all of three criteria are 'other business related activities', 'recreational, cultural and sporting activities' in Seoul, 'machinery and outfits, n.e.c', 'retail trade, except of motor vehicles and motorcycles, repair of personal and household goods' in Inchun. We conclude that each should strategically develop the region-oriented specialized industry which has the comparative advantage. It is the reason why the concentration of industry in necessary for the leading of regional industry under the weaken local public finance. Moreover, such an industy should provide the increase of employment and income from the viewpoint of the activation of regional economy. The potential-specialized competitive industry requires the advanced structure of production under the criteria of value-added. For the development of the metropolitan area's economy, the highly advanced technology industry including computer and electronics should be induced through the loosening of metropolitan regulation. Research center(science park) supported by th private-public sector should be built for the increase of technology sector should be built for the increase of technology power of the small and medium enterprises, Also it is necessary that the small and medium enterprises strategically make the cooperative-large group in order to avoid the disadvantage from the size.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.2
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• pp.118-125
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• 1990

An optimal file allocation algorithm which seeks optimal solution of file allocation problem for efficient management and operation of information files in distributed computer system is proposed. Since file allocation time in practical applications that have many computer sites is tool long, the problem size has to be reduced and computation time is improved by using preassignment conditio. A new method which calculate appriasal value for accurrate value for accurrate representation of assigned state is proposed and the selection criteria to candidate nodes for rapid determination of allocation are given. By using selection criteria, file allocation is determined and final appraisal value represent total cost of assigned state.

• Journal of the Korean Society of Costume
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• v.57 no.2 s.111
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• pp.172-189
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• 2007

The purpose of this study was to identify the characteristics of ambivalent consumption appeared in the purchase behavior of apparel products by the 4Ps element of marketing mix and to clarify the relation between consumption value and clothing involvement that were the antecedent variable. Among the 4Ps element of marketing mix, brand was selected in the exterior criteria of products, and fashionability was selected in the internal criteria of products. Meanwhile, it was considered that there were no objects of conflicted or ambivalent criteria in the element of promotion. Finally, brand, fashionability, price, place, etc. were selected as the elements of marketing. A self-administered questionnaire was distributed to 550 subjects from Jun, 8th, 2006 to Jun, 22nd, 2006; 507 were used for the data analysis. The results from data analysis were following: firstly, it was identified that ambivalent consumption showed up, as the result from measuring the individual conflicting consumption by elements. Brand was the highest in the frequency of ambivalent consumption among the elements of marketing mix, and price, place, and fashionability were followed. Secondly, by product characteristics, the frequency of ambivalent consumption of casual shirt, group II, was lower than that of mountain climbing jacket, group III, in the brand element and the price element. Thirdly, as the results from conducting factorial analysis to consumption value, it had 5 dimensions, which were practical value, distinguishable/aesthetic value, conspicuous value, social/confirmative value, and enjoyable value. Also clothing involvement was classified into 4 dimensions of emotion, fashionability, symbolic and brand involvement in the result from conducting the factorial analysis to clothing involvement. Fourthly, the mean of ambivalent consuming group by each element was highest among that of other consuming groups in all the dimensions. Fifthly, ambivalent consuming group had the highest mean among other consuming groups in all the dimension of clothing involvement, such as emotion, fashionability, and symbolic by each element of marketing mix, and it means that overall, ambivalent consuming group is highly involved in all the dimension of clothing involvement.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.3
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• pp.398-407
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• 1999

In the present image processing technique, the concept of the gradient indicator(GI) has been introduced to find out the depth-of-field in sizing large particles ranging from $30{\mu}m$ to $30{\mu}m$ where using of the concept of the normalized contrast value(VC) is not appropriate. The gradient indicator is defined as the ratio of the local value to the maximum possible value of the gray-level gradient in an image frame. The gradient indicator decreases with the increases of the particle size and the distance from the exact focal plane. A particle is considered to be in focus when the value of the gradient indicator at its image boundary stays above a critical value. This critical gradient indicator($GI_{critical}$) is defined as the maximum gradient indicator($GI_{max}$) subtracted by a constant ${\Delta}GI$ which is to account for the particle-size effect. In the present ca.so, the value of ${\Delta}GI$ was set to 0.28 to keep the standard deviation of the measured particles mostly within 0.1. It was also confirmed that, to find the depth-of-field for small particles(${\leq}30{\mu}m$) with the same measurement accuracy, tho concept of the critical normalized contrast($VC_{critical}$) is applicable with 85% of the maximum normalized contrast value($VC_{max}$). Finally, the depth-of-field was checked for the size range between $10{\mu}m$ and $300{\mu}m$ when the both in-focus criteria ($GI_{critical}$ and $VC_{critical}$) were adopted. The change of the depth-of-field with the particle size shows good linearity in both the VC-applicable and the GI-applicable ranges with a reasonable accuracy.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.3
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• pp.33-48
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• 2022

This study aimed to investigate bag purchase behaviors according to materialism value. The subjects were 443 male and female adult consumers in their 20s to 50s. The research method was a survey, and the questionnaire consisted of questions on materialism value, bag purchase behaviors, and demographic characteristics. For data analysis, descriptive statistics, Cronbach's α, χ² test, factor analysis, cluster analysis, ANOVA, and Duncan's multiple range test were performed. The results of this study were as follows. First, materialism value was derived from three factors (happiness pursuit, possession-oriented, and success judgment). Second, subjects could be divided into three groups (happiness pursuit group, success judgment pursuit group, and immaterialism group) based on the materialism value variable. Third, the derived groups showed many differences in bag purchase behaviors. The happiness pursuit group considered all bag evaluation criteria factors (practicality, aesthetics, economy, symbolism) and bag purchasing information sources factors (mass media and personal sources) more than other groups, and showed a tendency to prefer select shops and complex shopping malls as bag purchasing places. In addition, the average annual cost and frequency of purchasing bags of this group were higher than those of other groups. The success judgment pursuit group considered symbolism as a bag evaluation criteria more than other groups, and considered personal sources as bag purchasing information sources more than mass media sources, and preferred luxury stores and department stores as bag purchasing places. On the other hand, the immaterialism group considered practicality and aesthetics as bag evaluation criteria and placed less importance on all information sources than other groups, and preferred Internet shopping malls as purchasing places. This group had the lowest average annual purchase cost and frequency among the three consumer groups. This study suggested that materialism value is a useful variable to segment male and female adult consumer markets effectively, and to understand the bag purchase behaviors of consumer groups divided by materialism value.