• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.67-79
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• 2001

This study is based on Parasuraman, Zeithaml 8l Berry［19］`s SERVQUAL measure that develop for estimation of service quality, so this study proposes the present condition of customer service and improvement method on internet search engine. This study also develops a questionnaire for analyzing customer satisfaction considering the present condition of internet service. We're going to analyze the customer service quality that classified by search engines, service quality with university students who use usually internet.

• Nuclear Engineering and Technology
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• v.37 no.2
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• pp.177-184
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• 2005

The Multivariate State Estimation Technique (MSET) is being used in Nuclear Power Plants for sensor and equipment condition monitoring. This paper presents the use of regularization methods for optimizing MSET's predictive performance. The techniques are applied to a simulated data set and a data set obtained from a nuclear power plant currently implementing empirical, on-line, equipment condition monitoring techniques. The results show that regularization greatly enhances the predictive performance. Additionally, the selection of prototype vectors is investigated and a local modeling method is presented that can be applied when computational speed is desired.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.171-180
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• 1999

Industrial equipment reliability improvement and maintenance is gaining attention as the next great opportunity for manufacturing productivity improvement. Reactive maintenance is expensive because of extensive unplanned downtime and damage to machinery. To avoid such an unplanned machine downtime, it is needed to use proactive maintenance approach by either using historical maintenance data or by sensing machine conditions. This paper discusses failure diagonosis and prediction based on the condition-based maintenance and reliability technique. Thus, by enabling such a framework, it can bring us more efficient planning and execution of maintenance to reduce costs and/or increase profits.

• Vacuum Magazine
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• v.2 no.2
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• pp.24-28
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• 2015

The brightness of an electron source, along with the aberrations of an objective lens, determines the image resolution and beam current on samples, which are two important parameters for evaluating the performance of an electron microscope. Here we introduce thermal electron source, Schottky emitter and cold field electron emitter. Thermal electron source is the cheapest and stable electron source but it has the lowest brightness. Schottky emitter is 10000 times brighter than tungsten thermal electron source, but requires ultrahigh vacuum operating condition. Cold field electron emitter is 10 times brighter than Schottky emitters, but it is rather unstable and its operation requires most stringent vacuum condition, hindering its widespread use.

• Korean Journal of Plant Resources
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• v.2 no.1
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• pp.235-241
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• 1989

The study was conducted to determine the Ms orthogonaL modia and the concentration of plant growth regulator for seed matura-tion and growth of rhizome from Cymbidium goeringii Germination waswell in dark condition, but the growth of rhizome was better un-der dark than under light condition in MS orthoTonal . Sucrose con-centration( 3 %) gave better results than higher ones(6%), andthe use of NAA(0.1 PPm) effect significant difference of seed ge-rmination .But the growth of rhizome was best in medium Containingsucrose concentration(3%) Ippm NAA and 1 PPm BA.

• Journal of Korean Society for Quality Management
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• v.25 no.2
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• pp.1-14
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• 1997

This paper considers maximum likelihood (ML) estimation of lifetime distribution under stress bounded ramp tests in which the stress is increased linearly from used condition stress to the stress u, pp.r bound. The following assumptions are used: exponential lifetime distribution under a constant stress, an inverse power law relationship between stress and mean of exponential lifetime distribution, and a cumulative exposure model for the effect of changing stress. Likelihood equations for the parameters involved in the model and asymptotic distribution of the estimators are obtained, and a numerical example is given.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.2
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• pp.151-165
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• 2013

Objectives: The purpose of this study is to investigate use condition of Korean medical institution and demand of Korean Medical Treatment Project of Infertility in infertile couple. Methods: Questionnaires were distributed to all members of the incorporated association AGAYA(http://www.agaya.org/) via e-mail and to infertile women who visited to Korean medicine OB & GY outpatient clinic of university Korean medicine hospitals of the country and an infertility specialized Korean medicine hospital. One hundred twenty four of completed questionnaires were analyzed. Results: 1. Korean medical institution utilization rate of infertile couple was 89.6% and was similar with western medical institution utilization rate of 87.1%. 2. 96.8% of infertile couple answered that Korean Medical Treatment Project of Infertility is necessary. And 90.3% of infertile couple answered that herbal medicines should be supported first of all. 3. 90.3% of infertile couple answered that they will participate if Korean Medical Treatment Project of Infertility go ahead. Conclusions: It was confirmed that most of the infertile couple have been received Korean medical treatment for infertility, and think that Korean Medical Treatment Project of Infertility is necessary.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1215-1220
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• 2004

Reactive distillation (RD) is a combination process where both separation and reaction are considered simultaneously in a single vessel. This kind of combination to enhance the overall performance is not a new attempt in the chemical engineering areas. The recovery of ammonia in the classic Solvay process for soda ash of the 1860s may be cited as probably the first commercial application of RD. The RD system has been used for a long time as a useful process and recently the importance of the RD is enlarged more and more. In addition to that, the application fields of RD are diversely diverged. To make the most of the characteristic of RD system, we must decide the best operating condition under which the process shows the most effective productivity and should decide the best control algorithm which satisfies an optimal operating condition. Phosgene which is a highly reactive chemical is used for the production of isocyanates and polycarbonates. Because it has high reactivity and toxicity, its utilization is increasingly burdened by growing safety measures to be adopted during its production. Dimethyl Carbonate (DMC) was proposed as a substitute of phosgene because it is non-toxic and environmentally benign chemical. In this study, RD is used for DMC production process and the transesterification is performed inside of column to produce DMC. In transesterification, the methanol and ethylene carbonate (EC) are used as the reactants. This process use homogeneous catalyst and the azeotrope exists between the reactant and product. Owing to azeotrope, we should use two distillation columns. For this DMC production process, we can suggest two configurations. One is EC excess process and the other is methanol excess process. From the comparison of steady state simulation results where the Naphtali-Sandholm algorithm is used, it showed the better performance to use the methanol excess process configuration than EC excess process. Then, the dynamic simulation was performed to be based on the steady state simulation results and the optimal control system was designed. In addition to that, the optimal operating condition was suggested from previous results.

• Culinary science and hospitality research
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• v.14 no.4
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• pp.79-92
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• 2008

This study was to investigate consumers' recognition, preference, and use condition of processed food of Prunus mume(PFPM). As for the general recognition of Prunus mume, as the age is higher, and as the group of manufacture and intake has a higher level of academic attainments, the level of recognition is high. The group that manufactures and takes in PFPM at home showed high preference for Prunus mume processed food, and significant differences were shown among groups in this regard. The group of higher age and academic attainment level and those who manufactured Prunus mume at home showed high intake frequency of PFPM. 88.7% of the all respondents said that they had had Prunus mume products such as Prunus mume alcoholic beverage(76.3%), undiluted solution of Prunus mume(74.9%), Prunus mume tea(60.1%), and Prunus mume Jjangajji, or sliced vegetables preserved in soy sauce or hot pepper paste(46.3%). The rates of intake experience on another PFPM were relatively very low, and PFPM consumers in Daegu and Gyeongbuk areas were very limited. As for the prospect of Prunus mume processed food consumption, 48.8% and 46.7% of the respondents expected that it would remain in the current condition and would increase respectively. Moreover, 62.8% of the respondents said that they would purchase new PFPM satisfying such requirements above, which suggests that producing new PFPM is very positive.

• Journal of Environmental Science International
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• v.25 no.1
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• pp.99-105
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• 2016

In this paper, a groundwater hydrological study of the Gyeongju well during the Silla period is conducted to investigate how sufficiently the Gyeongju well supplied water demand at the time. It is assumed that the current geology and soil condition in Gyeongju remain similar to the Silla period. Also, the land use and land coverage during the Silla period is estimated based on the current land condition in Gyeongju. Precipitation during the Silla period is analyzed using precipitation data from 1984 to 2014 provided by Gyeonju weather station. Precipitation analysis is applied based on 3 different scenarios; precipitation intensity during the Silla period was Case (1) the same as, Case (2) 30% more, and Case (3) 30% less than the precipitation intensity of the last decade (2005~2014). Furthermore, to observe the use of the well in Gyeongju during droughts, the following condition(Case (4)) is also considered; ten year drought during the Silla period was the same as the ten year drought from 1984 to 2014. Available amount of groundwater development is analyzed using NRCS-CN method. The results show that the potential amount of groundwater in Gyeongju during Silla era was for Case (1) $62,825,272m^3/year$, Case (2) $93,606,567m^3/year$, Case (3) $32,277,298m^3/year$, and Case (4)$32,870,896m^3/year$. Also, it has been shown that $45,260,000m^3$ of groundwater were required to supply to all households in Gyeongju during Silla era. Therefore, if the precipitation intensity during Silla era was similar with the last decade, the groundwater would provide enough supply to all households in Gyeongju. However, in the case that the precipitation intensity during Silla era was 30% less than the last decade or a ten year drought happened, it is predicted that the water use in Gyeongju would have been limited.