• The Korean Journal of Pain
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• v.34 no.3
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• pp.346-368
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• 2021

Background: Recalcitrant disc herniation may result in chronic lumbar radiculopathy or sciatica. Fluoroscopically directed epidural injections and other conservative modalities may provide inadequate improvement in some patients. In these cases, percutaneous neurolysis with targeted delivery of medications is often the next step in pain management. Methods: An evidence-based system of methodologic assessment, namely, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used. Multiple databases were searched from 1966 to January 2021. Principles of the best evidence synthesis were incorporated into qualitative evidence synthesis. The primary outcome measure was the proportion of patients with significant pain relief and functional improvement (≥ 50%). Duration of relief was categorized as short-term (< 6 months) and long-term (≥ 6 months). Results: This assessment identified one high-quality randomized controlled trial (RCT) and 5 moderate-quality non-randomized studies with an application of percutaneous neurolysis in disc herniation. Overall, the results were positive, with level II evidence. Conclusions: Based on the present systematic review, with one RCT and 5 non-randomized studies, the evidence level is II for percutaneous neurolysis in managing lumbar disc herniation.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.54-65
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• 1993

The paper describes and alternative method based on a new idea to measure the circular movement of machining centers. ISO has employed three testing methods for the acceptance tests of machine tools; the first is a rotating one-dimensional probe method, the second is a two-dimensional probe and a master circular ring, and the third is a kinematic ball bar. The last two methods were proposed and introduced by W. Knapp and J. B. Bryan, respectively. The newly developed method is superior to above two methods; the rotating angle can be detected and the rotating radius is variable. Circular movement errors of machining centers were investigated by the analysis of data measured by R- .THETA. method. Followint observations are obtained 1) The errors which depend on positions, i.e., periodical errors by the pitch of ball screws, errors by compensation of backlash and errors by perpendicularity of X and Y-axis, were analyzed. 2) The errors which depend on NC control system, i.e., errors by the unbalance of position-loop-gaians, errors by velocity-loop-gains and errors by feed speeds, were quantiatively analyzed. 3) The method of extracting error information, which uses moving technique of averaging angle and fourier's analysis data mesured by the R- .THETA. method, was proposed.

• Journal of Korean Institute of Industrial Engineers
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• v.7 no.2
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• pp.19-26
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• 1981

A special case of the probabilistic multi-location problem is studied in a two-echelon logistic system for deteriorating items. The objective is to determine the location of the minimum number of supply centers among a discrete set of location sites of supply centers, such that the probability each retailer being covered by some supply center is not less than a specified value. A logistic cost is introduced as performance measure of the system, and leads us to analyze the impact of deterioration rate on the location problem. The results obtained from numerical examples are discussed, which provides effective guidelines that can be used for the logistic managerial decisions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.4
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• pp.45-52
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• 2009

The objective of this was to improve a transportation cost relation between Central Distribution Centers(CDCs) and Regional Distribution Centers(RDCs), to control inventory cost concerning safety stock for each service level, by reviewing distribution steps connecting CDCs and RDCs under the price discount. It was also to examine and compare operating costs for the following two alternative suggestions for setting the service standard as a counter measure for a stock-out of the distribution network system management. First, provision by dispersing the safety stock to the CDCs and RDCs; and second, exclusive provision of the safety stock only to the RDCs. The cost comparison analysis was made for each category of purchase costs, regular transportation costs, express transportation costs, and inventory holding costs.

• The Korean Journal of Franchise Management
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• v.3 no.1
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• pp.130-143
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• 2012

Franchise store retailing is taking on ever greater roles in business and commerce in China. The diverse product range, small-batch order, high frequency and time-specific requirements inherent in retail logistics make it the most complicated of all categories of logistics. In franchise store retailing, expanding business scales make trans-regional development a trend. Without a well-functioning logistic system, the standardized delivery of products would be held back, impacting trans-regional development strategy and operational costs. Therefore, the efficiency of franchise store retailing largely depends on logistical efficiency. The integrated and streamlined management of franchise stores depends in large measure on their logistical centers. As such, logistical centers constitute the key link and bears on core competitiveness in franchise store retailing. This thesis begins with an analysis of the current developments and four basic logistical models of franchise store retailing in China, proceeds to summarize developmental trends as well as focal issues and proposes an efficiency enhancing plan.

• Journal of the Optical Society of Korea
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• v.18 no.4
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• pp.317-329
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• 2014

In vision measurement systems based on structured light, the key point of detection precision is to determine accurately the central position of the projected laser line in the image. The purpose of this research is to extract laser line centers based on a decision function generated to distinguish the real centers from candidate points with a high recognition rate. First, preprocessing of an image adopting a difference image method is conducted to realize image segmentation of the laser line. Second, the feature points in an integral pixel level are selected as the initiating light line centers by the eigenvalues of the Hessian matrix. Third, according to the light intensity distribution of a laser line obeying a Gaussian distribution in transverse section and a constant distribution in longitudinal section, a normalized model of Hessian matrix eigenvalues for the candidate centers of the laser line is presented to balance reasonably the two eigenvalues that indicate the variation tendencies of the second-order partial derivatives of the Gaussian function and constant function, respectively. The proposed model integrates a Gaussian recognition function and a sinusoidal recognition function. The Gaussian recognition function estimates the characteristic that one eigenvalue approaches zero, and enhances the sensitivity of the decision function to that characteristic, which corresponds to the longitudinal direction of the laser line. The sinusoidal recognition function evaluates the feature that the other eigenvalue is negative with a large absolute value, making the decision function more sensitive to that feature, which is related to the transverse direction of the laser line. In the proposed model the decision function is weighted for higher values to the real centers synthetically, considering the properties in the longitudinal and transverse directions of the laser line. Moreover, this method provides a decision value from 0 to 1 for arbitrary candidate centers, which yields a normalized measure for different laser lines in different images. The normalized results of pixels close to 1 are determined to be the real centers by progressive scanning of the image columns. Finally, the zero point of a second-order Taylor expansion in the eigenvector's direction is employed to refine further the extraction results of the central points at the subpixel level. The experimental results show that the method based on this normalization model accurately extracts the coordinates of laser line centers and obtains a higher recognition rate in two group experiments.

• Journal of Korean Library and Information Science Society
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• v.40 no.4
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• pp.227-242
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• 2009

The objective of this study is to work out a data-based educational and cultural program that can best identify the original role of library in a measure to activate it. To achieve this goal and introduce an educational and cultural program that would faithfully meet the desired characters of library, a research was made to examine the theoretical aspects of educational and cultural programs offered by public libraries, compare and analyze those conducted at the public libraries and life-long educational centers of the local autonomous bodies in Jeonbuk Province. Included in the research as subjects were 10 public libraries in the cities of the province including 5 branches of JeonJu Municipal Library and various educational and cultural programs operated directly by each municipal self-governing body under such title names as life-long educational centers, cultural houses, residential autonomy centers, women's halls, women's culture halls and women culture centers.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.904-914
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• 2011

The volumetric errors of CNC machining centers are determined by 21 errors, including 3 linear errors, 6 straightness errors, 3 perpendicular errors, 9 angular errors and non-rigid body errors of the machine tool. It is very time consuming and hard to measure all of these errors in which laser interferometer and other parts are used directly. Hence, as many as 21 separate setups and measurements are needed for the linear, straightness, angular and perpendicular errors. In case of the 5-axis machining centers, two more rotary tables are used. It can make 35 error sources of the movement. Therefore, the measured errors of multi movements of the 5-axis tables are very complicated, even if the relative measured errors are measured. This paper describes the methods, those analyze the error sources of the machining centers. Those are based on shifted diagonal measurements method (SDM), R-test and Double ball bar. In case, the angular errors of machine are small enough comparing with others, twelve errors including three linear position errors, six straightness errors and three perpendicular errors can be calculated by using SDM. To confirm the proposed method, SDM was applied to measuring 3 axes of machine tools and compared with directly measurement of each errors. In addition, the methods for measuring relative errors of multi-axis analysis methods using R-test and Double Ball Bar are introduced in this paper.

• Journal of Korean Library and Information Science Society
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• v.43 no.2
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• pp.99-116
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• 2012

This study recommends the evaluation measures and indicators to evaluate the operations and performance of each Foreign Research Information Centers (FRIC) established to support the effective and efficient use of the foreign academic journals at the national level. The indicators are comprised by 3 major sections, subdivided into 35 sub-indexes. Each of indicators is scored according to the weights derived from the AHP survey to the related researchers and the practitioners. As a result, total score of 1,000 is distributed to 3 major sections of operational strategy section (190), operational systems section (440), and operational outcomes (370). Based on the evaluation indicators, measure dictionary is developed, followed by preliminary tests both by the parent organization and by each centers, in order to check the feasibility of the measurement.

• Health Policy and Management
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• v.23 no.4
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• pp.434-444
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• 2013

Background: Regional Cardiocerebrovascular Centers (RCC) were established for the prevention and treatment of cardiocerebrovascular disease and funded by the Ministry of Health and Welfare. The purpose of this study was to develop and validate the measurement tool of public benefits in RCC. Methods: Through the intensive literature review, experts surveys and their repetitive feedback, we selected the 46 items about the public benefits in RCC. Development of measurement tool involved content validity test using Content Validity Index (CVI), construct validity test through factor analysis and reliability test. Results: Thirty-five items were selected by content validity test, which CVI was 0.08 or higher. Through the construct validity test, 32 items in 7 factors were derived. And Cronbach's alpha was 0.951. Finally, public benefits measurement tool is composed of 32 items in 7 factors which are comprehensiveness of health care services, market complement, emergency care, cost, governance, quality improvement, and government control. Conclusion: Though we developed the measurement tool of public benefits in RCC, it would be utilized to measure the public benefits of various health agencies.