• 제목/요약/키워드: measure centers

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The role of percutaneous neurolysis in lumbar disc herniation: systematic review and meta-analysis

  • Manchikanti, Laxmaiah;Knezevic, Emilija;Knezevic, Nebojsa Nick;Sanapati, Mahendra R.;Kaye, Alan D.;Thota, Srinivasa;Hirsch, Joshua A.
    • The Korean Journal of Pain
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    • 제34권3호
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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.

Machining Center의 2차원 원호보간정밀도 진단 System의 개발 (A development of accuracy diagnostic system 2-dimensional circular interpolation of machining centers)

  • 김정순;남궁석;제정신
    • 한국정밀공학회지
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    • 제10권2호
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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.

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A STUDY ON A PROBABILISTIC MULTI-LOCATION PROBLEM IN A TWO-ECHELON LOGISTIC SYSTEM FOR DETERIORATING ITEMS

  • Hwang, Heung-Seok;Hwang, Hak
    • 대한산업공학회지
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    • 제7권2호
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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.

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가격할인하 안전재고 합리화를 위한 분배시스템 운영에 관한 연구 (A Study on the Operation of Distribution System for the Rationalization of Safety Stock under the Price Discount)

  • 김병찬;김홍기
    • 산업경영시스템학회지
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    • 제32권4호
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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.

A Study on Logistical System and Operational Models of Franchise Store Retailing in China

  • Li, Dong-xin;Kang, Tae-won
    • 한국프랜차이즈경영연구
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    • 제3권1호
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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.

Adaptable Center Detection of a Laser Line with a Normalization Approach using Hessian-matrix Eigenvalues

  • Xu, Guan;Sun, Lina;Li, Xiaotao;Su, Jian;Hao, Zhaobing;Lu, Xue
    • Journal of the Optical Society of Korea
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    • 제18권4호
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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.

전북지역 공공도서관 교육문화프로그램 분석연구 (A Study on the Educational and Cultural Programs of Public Libraries in Jeonbuk Provincial Area)

  • 최흥식;서진순
    • 한국도서관정보학회지
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    • 제40권4호
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    • pp.227-242
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    • 2009
  • 본 연구의 목적은 도서관 고유의 정체성에 부합하고 이를 활성화하는 방안으로 자료를 기반으로 한 교육문화프로그램을 모색해 보자는데 있다. 이러한 목적을 달성하기 위하여 본 연구는 공공도서관 교육문화프로그램의 이론적 내용을 살펴보고, 전라북도 지자체하에서 운영하는 공공도서관과 평생학습운영기관의 교육문화프로그램을 비교분석하여 공공도서관 본래의 특성을 살린 교육문화프로그램을 모색하고자 한다. 본 연구의 조사대상은 전주시립도서관산하의 5개관을 비롯한 각 시단위의 공공도서관 10개관과 각 시의 지자체 직영의 평생학습센터, 문화의집, 주민자치센터, 여성회관, 여성문화회관, 여성문화센터 등의 명칭으로 운영하는 교육문화프로그램을 조사, 분석하였다.

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머시닝센터의 다축오차 평가 방법 (Evaluation Method of the Multi-axis Errors for Machining Centers)

  • 황주호;심종엽;고태조
    • 한국정밀공학회지
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    • 제28권8호
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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.

외국학술지지원센터(FRIC) 평가지표 개발에 관한 연구 (A Study on the Development of Evaluation Measures and Indicators for Foreign Research Information Centers)

  • 오동근;여지숙;최성열
    • 한국도서관정보학회지
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    • 제43권2호
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    • pp.99-116
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    • 2012
  • 이 연구는 국가적 차원에서 외국학술지의 효율적 이용을 위해 설립된 외국학술지지원센터들의 운영전반과 성과를 평가하기 위한 평가지표를 개발하기 위해 시도된 것이다. 이를 위해 이 연구에서는 평가지표를 운영전략과 운영시스템, 운영성과의 세 부문으로 나누고, 이를 다시 8개 세부부문, 16개 지표, 35개 세부지표로 구분하여 제시하였다. 각각의 지표는 AHP 전문가설문조사 결과 도출된 가중치로 배점을 결정하였으며, 최종점수는 운영전략부문 190점, 운영시스템부문 440점, 운영성과부문 370점, 총 1,000점 만점으로 구성하였다. 개발된 평가지표를 바탕으로 평가지표정의서를 개발하였으며, 이 정의서를 기반으로 시범평가와 자체평가를 실시하여, 차후의 실제평가에서 나타날 수 있는 문제점들을 검토하도록 하였다.

권역심뇌혈관질환센터의 공익성 측정도구 개발 (Development and Validation of the Measurement Tool of Public Benefits in Regional Cardiocerebrovascular Center)

  • 이건세;신은영;정효선;이정현;김희숙;임영실;김영택Kun
    • 보건행정학회지
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    • 제23권4호
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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.