• The Korean Journal of Applied Statistics
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• v.34 no.5
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• pp.735-744
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• 2021

Maintaining the lifetime of a product is one of the objectives of quality control. In real processes, most samples are constructed with censored data because, in many situations, we cannot measure the lifetime of all samples due to time or cost problems. In this paper, we propose two cumulative sum (CUSUM) control charting procedures to monitor the mean of type I right-censored lognormal lifetime data. One of them is based on the likelihood ratio, and the other is based on the binomial distribution. Through simulations, we evaluate the performance of the two proposed procedures by comparing the average run length (ARL). The overall performance of the likelihood ratio CUSUM chart is better, especially this chart performs better when the censoring rate is low and the shape parameter value is small. Conversely, the binomial CUSUM chart is shown to perform better when the censoring rate is high, the shape parameter value is large, and the change in the mean is small.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• Communications for Statistical Applications and Methods
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• v.26 no.5
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• pp.445-461
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• 2019

It is possible that data are not always fitted with sufficient precision by the existing distributions; therefore this article presents a methodology that enables the use of families of asymmetric distributions as alternative probabilistic models for survival analysis, with censorship on the right, different from those usually studied (the Exponential, Gamma, Weibull, and Lognormal distributions). We use a more flexible parametric model in terms of density behavior, assuming that data can be fit by a distribution of stable distribution families considered unconventional in the analyses of survival data that are appropriate when extreme values occur, with small probabilities that should not be ignored. In the methodology, the determination of the analytical expression of the risk function h(t) of the $L{\acute{e}}vy$ distribution is included, as it is not usually reported in the literature. A simulation was conducted to evaluate the performance of the candidate distribution when modeling survival times, including the estimation of parameters via the maximum likelihood method, survival function ${\hat{S}}$(t) and Kaplan-Meier estimator. The obtained estimates did not exhibit significant changes for different sample sizes and censorship fractions in the sample. To illustrate the usefulness of the proposed methodology, an application with real data, regarding the survival times of patients with colon cancer, was considered.

• Journal of Distribution Science
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• v.20 no.6
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• pp.11-19
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• 2022

Purpose: This study aims at exploring and understanding the effect of four independent variables related to dairy retail marketing and distribution (deep freezers, promotions, company support and distributor-retailer relationship) and one moderating variable Covid-19 lockdown on sales of dairy product during the Covid 19 pandemic situation. Research design and methodology: Personal interviews and door-to-door surveys and promotional tools were designed to publicise and collect data from the retailers. The sale data before, during and after promotion activity were all recorded and evaluated to draw an inferential conclusion. Factor analysis and multiple regression methods were adopted to analyses the data collected. Results: The research shows that four out of the five factors studied was found having significant impact on dairy retail sales. The highest impact on sales was contributed by promotions, secondly by the deep freezer impact followed by distributor-retailer relationship during the study period and lastly but not the least due to influence of Covid-19 lockdown. Conclusions: The study contributes to the body of knowledge in cold chain distribution process through utilization of right mix of tools and tactics for effective marketing and distribution of dairy products in developing countries especially during a pandemic situation.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.297-306
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• 2017

The study was performed to determine the impact of the gastrocnemius taping with balance training on spasticity and balance ability of the ankle joint. A total of 25 stroke subjects were divided into two groups: a taping with balance training (n=14), a sham taping with balance training (n=11). Spasticity assesment was scored by modified ashworth scale. Balance ability assesment was performed by functional reach test (FRT), the timed up & go test (TUG). The stability index (SI), the left-right weight distribution (left-right WD), the toe-heel weight distribution (toe-heel WD) were analyzed in the eyes open conditions(EO) and eyes closed conditions(EC) conditions using by the Tetrax interactive balance system. The experimental group showed a significant improvement in SI, left-right WD and toe-heel WD in the EO and EC, MAS, FRT, TUG. In comparison between the groups, a significant improvement was detected in FRT, TUG, SI and left-right WD in the EO, and left-right WD and toe-heel WD in the EC. It was found out that a short period of balance training with taping is effective on spasticity and balance ability in stroke patients. Therefore, any stroke patient without skin damage is encouraged to use the gastrocnemius taping for balance rehabilitation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.3
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• pp.328-337
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• 2015

Objectives: The purpose of this study is to investigate differences in concentration according to the position at the left or right shoulder within a 30 cm of radius of workers' respirators and provide basic data for the establishment of an industrial health policy. Methods: Personal samples were collected from a total of 65 workers from 27 manufacturing firms in South Gyeongsang-do Province from November 5, 2011 to December 30, 2012 after classifying the laborers into left- and right-side groups. The organic compound samples were collected and analyzed in accordance with the NIOSH Manual of Analytical Methods (NMAM) 1501. Results: In terms of the concentration of organic compounds collected from both left and right shoulders at the position of workers' respirators, isobutyl acetate was the highest with 145 ppm at the left shoulder, followed by ethyl acetate (133.5 ppm) and toluene (38.13 ppm). At the right shoulder, on the contrary, ethyl acetate (149.3 ppm) was the highest, followed by toluene (46.26 ppm), xylene (29.63ppm) and isopropyl alcohol (28.06 ppm). Overall, the right shoulder was higher than the left shoulder in terms of concentrations. Conclusions: For the measurement of the working environment, workers' personal samples should be collected at the place closest to the respirator. In terms of the reduction of error, the attachment of two sample media is expected to reduce errors in exposure assessment.

• Cartoon and Animation Studies
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• s.15
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• pp.207-220
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• 2009

This paper researched that consumers who lived in the local small cites have a restricted and insufficient problem to screening the animation film comparing with those of capital area and the other broader local cities. And these kinds of problems caused more serious problems like a infringement of copy right as a result. This paper calculated and evaluated that the rate possibilities of criminal infringement copy right in supposing that giving the opportunity screening the all of the first-run movies the most highest criminal group in Chuncheon where the worst benefit area in aspect of screening circumstances. As a result of this research, this paper could suggest that the possibility to reduce the criminal infringement of copy right and the necessity of structural reconstruction throughout rebuilding of animation distribution and consciousness of consumers. Thus this paper try find out the importance of reducing the rate of criminal infringement copy right by recontruction of structrual access of local animation business.

• Journal of the Korean Society for Library and Information Science
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• v.55 no.3
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• pp.131-154
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• 2021

This study is to in-depth analysis of the copyright issues related to the library's e-book service, which is the cause of the recent conflict between the publishing industry and the library industry. To this end, the purpose and outline of the copyright system were briefly summarized. Then, the jurisprudence of the Copyright Act applied to the borrowing of paper books and e-books was analyzed, and the position of the publisher's association and the library industry were reviewed together. In addition, problems of the current copyright act related to e-book services were diagnosed and directions for improvement were sought. Unlike in the case of paper books, first sale doctrine does not apply to e-book borrowing, so the library cannot acquire the right to service just by purchasing e-books. Based on the contract signed with the distributor in the process of purchasing the e-book, the library acquires the right to service the e-book. However, if the validity period of the exclusive publication right expires, the contract itself becomes invalid, which can cause serious problems in the stability of library services and preservation of resources. In order to solve this problem, it is suggested that the first sale doctrine needs to be extended to digital works.

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.E
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• pp.20-32
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• 1990

Abstract This study was conducted to pursue the normalization of frequency distribution by making an approach to the coefficient of skewness to nearly zero through the Box-Cox transformation, to get probable flood flows can be calculated by means of the transformation equation which has been derivated by Box-Cox transformation in the annual maximum series of the applied watersheds. It has been concluded that Box-Cox transfromation is proved to be more efficient than logarithmic, square root and SMEMAX transformation which is based on the trigonometric solution of a right triangle whose three verteces repesent the smallest, median and largest observed values of a population in making the coefficient of skewness nearer to zero. Consequently it is shown that probable flood flows according to the return period based on Box-Cox transformation are closer to the observed data as compared to other methods including SMEMAX transformation and fitted probability distributions such as the three parameter lognormal and the type I extremal distribution for the applied watersheds.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.7-11
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• 2003

for many years already, testing laboratories, research institutes and manufactures try to find a reliable water tree accelerated ageing test that is able to show whether a polymer Medium Voltage cable os susceptible to water treeing or not. Test on laboratory samples, model cable designs, and fell size cable are presented. Apart form aging, another important aspect of any accelerated aging test is the right choice of th preconditioning method. THTS paper is the analysis of weibull distribution method after an accelerated aging test of MV(Medium Cable) cable.