• 상하수도학회지
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• 제23권2호
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• pp.215-222
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• 2009

This study compares the performance of the filters with various media in pretreatment of seawater desalination by reverse osmosis. For this purpose, Masan bay seawater is used as raw water. The filter performance is evaluated by the filtrate quality and the head loss development. Five media is selected in this study: anthracite, $Filtralite^{(R)}$, sand, Pumice, $AFM^{(R)}$. These media are used in combination for dual media filter and alone for mono media filter. The comparison results show that NC0.8-1.6 is the best $Filtralite^{(R)}$. The dual media filter of NC0.8-1.6 and sand outperformed other filters in particle removal. The dual media filter of anthracite and sand showed good performance in organic removal. The mono media filter of Pumice produced the similar filtrate quality as the mono media filter of sand although the effective size of Pumice is considerably greater than that of sand. Due to big size, head loss development is maintained slow in the filtration of Pumice.

• Journal of Power Electronics
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• 제19권4호
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• pp.894-906
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• 2019

In this paper, a DC-DC converter is proposed based on the Cuk converter. The proposed converter has high efficiency and it can be used in multilevel DC-DC converters. A reduction of the inductors size in comparison to Cuk converter and a reduction in the inductors resistance negative effects on efficiency are the important points of the proposed converter. Its voltage ripple is reduced when compared to other converters. Its output voltage has a high quality and does not contain spikes. A theoretical analysis demonstrates the positive points of the proposed converter. The design and analysis of the converter are done in continues conduction mode (CCM). Experiments confirm the obtained theoretical equations. The proposed converter voltage gain is similar to that of a conventional Boost converter. As a result, they are compared. The comparison illustrates the advantages of the proposed converter and its higher quality. Furthermore, a prototype of the proposed converter and its combination with a 2x multiplier are built in the lab. Experimental results validate the analysis. In addition, they are in good agreements with each other.

• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4652-4659
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• 2022

Among the detector materials available at room temperature, thallium bromide (TlBr), which has a relatively high atomic number and density, is widely used for gamma camera imaging. This study aimed to verify the usefulness of TlBr through quantitative evaluation by modeling detectors of various compound types using Monte Carlo simulations. The Geant4 application for tomographic emission was used for simulation, and detectors based on cadmium zinc telluride and cadmium telluride materials were selected as a comparison group. A pixel-matched parallel-hole collimator with proven excellent performance was modeled, and phantoms used for quality control in nuclear medicine were used. The signal-to-noise ratio (SNR), contrast to noise ratio (CNR), sensitivity, and full width at half maximum (FWHM) were used for quantitative analysis to evaluate the image quality. The SNR, CNR, sensitivity, and FWHM for the TlBr detector material were approximately 1.05, 1.04, 1.41, and 1.02 times, respectively, higher than those of the other detector materials. The SNR, CNR and sensitivity increased with increasing detector thickness, but the spatial resolution in terms of FWHM decreased. Thus, we demonstrated the feasibility and possibility of using the TlBr detector material in comparison with commercial detector materials.

• 품질경영학회지
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• 제28권4호
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• pp.1-15
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• 2000

Nowadays, consumers' consciousness on me quality are very diversified and their pattern is changing from the price-priority to me quality-priority. So they prefer good-quality products without defects. Therefore quality is a core competence. To compete with me facts, it is very important to keep me the quality competence. To do so, one way is to introduce 100ppm quality innovation system. Many corporates introducing 100ppm improved defect rations(not only process defect ratios but also product defect ratios). In these respects, this study focuses on the comparison and measurement of performance by the analysis of quality system between 100ppm corporates and non-100ppm corporates. Second, this focuses on the finding out core competence reinforcement factors according to the introducing of 100ppm quality system to improve the performance. Third, this focuses on the persuading to introduce the 100ppm quality system to the non-100ppm corporates. Last, this focuses on the playing on the role of guidance to improve QM efficiency.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.324-329
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• 1997

This paper introduces experimental results of ride values assessed for domestic and overseas passenger cars. The experiment was executed about four vehicles, three Korean persons, and two roads by measuring human 12-axis. The results include the comparison of the component ride values, overall ride value, and seat effective amplitude transmissibility. The relative comparison of the ride values for different cars is shown in this paper, which may lead us to judge the current address of Korean ride quality-related technology.

• 대한통합의학회지
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• 제4권3호
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• pp.1-15
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• 2016

Purpose : The purpose of this study was to evaluate the difference of early muscle strengthening exercise(starting at 1 week) on pain, function and sleep quality for rotator cuff partial tear patients. Method : Experimental group 15 people, control group 15 people, was a total of 30 people. Group-specific arbitration method, was applied to early muscle strengthening exercise (experimental group) and general movement treatment(Starting at 6 week) (control group). Both groups were subjected to 40 minutes of basic physical therapy interventions four times a week over an six-week intervention period. In this study, Pain, function and sleep quality measured by VAS, PPT and ROM, CMS, SST and PSQI. Result : 1. The VAS and PPT in the experimental group and control group before and after treatment were significant difference(p<.01). Comparison between the two groups in the change in motion before and after treatment also showed a statistically significant(p<.01). 2. Comparison functional Assessment of the shoulder ROM, CMS and SST in the experimental group and control group before and after treatment were significant difference(p<.01). ROM was not significant differences between the groups but CMS and SST were significant differences between the groups. 3. PSQI in the experimental group and control group before and after treatment were significant difference(p<.01). Comparison between the two groups in the change in motion before and after treatment also showed a statistically significant(p<.01). Conclusion : Therefore, early muscle strengthening exercise is useful to improve the shoulder function and pain for rotator cuff tear patients.

• 한국수소및신에너지학회논문집
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• 제28권3호
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• pp.287-294
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• 2017

EVs manufacturers typically target a range of 300 km on a fully charged battery. Many studies have been conducted to improve these disadvantages. As a results, the mileage of EVs is expected to increase significantly. However, as the distance traveled by EVs increases, current test method (SCT) have many difficulties. The biggest problem is that it takes a lot of time to test an EVs and greatly increases the error rate during the test period. In order to solve these problems, this paper discusses the fuel economy test method of EVs for energy efficiency and mileage. The comparison of test methods was achieved by chassis dynamometer test about EVs. These review of test methods are intended to both improve testing efficiency and provide a practical testing methodology that can be easily adapted to accommodate future testing enhancements. In conclusion, the results of MCT mode and SCT mode comparison show similar results within 3 %, confirming that the test method is appropriate. Also, as the CSCM distance becomes shorter in the MCT mode, the mileage becomes longer and the fuel economy becomes lower. As a result, the error from the SCT test results is expected to increase. In order to minimize the error of SCT measurement fuel economy, it is recommended to maximize the CSCM driving distance. However, since the timing of the EOT is not clearly known, it is reasonable to define the allowable range of the CSCE to be within 20 % of the MCT total mileage.

• 동서간호학연구지
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• 제9권1호
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• pp.74-82
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• 2004

Purpose: This study has been conducted as a quality improvement activity in order to confirm the assessment of patients, their guardians and nurses by providing them with a Life in Hospital Guide. Method: Nursing with Life in Hospital Guide provision was conducted at an University Hospital with patients admitted within 5 days or less and their guardians, a control group of 375 persons and a comparison group of 372 persons, and the data have been collected from the 26th of May to the 10th of October 2003. A Life in Hospital Guide, in the form of a leaflet, that contained useful information such as meals, facilities, car parking, documents, linen products etc, was used. The collected data have been analysed using SPSS windows programme 11.0 for percentage, $X^2$-test, and t-test. Result: The comparison group who were provided with a Life in Hospital Guide will know better about the articulars needed to live in hospital than the control group who were not,' the average of the comparison group (4.04) was higher than the control group (3.04), which is a significant difference (t=-27.06, p=.000). Conclusion: As a results of this study, it was confirmed that life in hospital guidance through a leaflet each as a quality improvement activity, are effective.

• 한국농공학회논문집
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• 제47권5호
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• pp.75-86
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• 2005

Recently since urbanization has brought about a dried stream and a worse water quality, Anyang city discharged the third treated sewage into the upper stream of Anyancheon and Hakuicheon. As the result, Hakuicheon had the water level and velocity enough for a living thing in the water to live in but water quality was worse than it had been. Therefore in case of meeting the water level and velocity of the second grade water-quality which living things in the water can live in, the discharge and water quality to secure in-stream flow must be at least 0.350 $m^3/s$ and $BOD_5\;3.2 mg/{\iota}$ respectively. In Anyancheon the water level was increased a little higher than it had been but the velocity was almost unchanged in comparison with it before. On the other hand the water quality was a little better than it had been. Therefore in case of meeting the water level and velocity of the third grade water-quality that people can do water-friendly activity, the discharge and water quality to secure in-stream flow must be at least 0.688 $m^3/s$ and $BOD_5\;4.8 mg/{\iota}$ respectively. The water-quality prediction on the suggested eight scenarios was simulated in all satisfying the third grade water-quality.

• 품질경영학회지
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• 제48권1호
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• pp.227-239
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• 2020

Purpose: The purpose of this study is to introduce the improving attorney system. It was confirmed by document writing that the staff in the field in Korea had the most difficulty in the Quality circle activities. The reform improving attorney is a quality expert at the Quality Secretariat and assists them in their documentation. Methods: Just as a patent attorney helps to get a patent, an improving attorney system helps document the improvement results of the field Quality circle and even standardizes the company. The process of introducing an improving attorney includes the declaration of an improving attorney are 11 levels of work. Results: An improving attorney was conducted in 600 organizations for 18 months. As a result of the comparison of the number of cases before and after the introduction of the improving attorney, the number of solution problem was lowered to 9 before 2016 and 8 in 2017, but after the introduction, it increased exponentially to 181 in 2018 and 162 in August 2019. In 2016 and 2017, only one standard was registered, but 64 standards were registered in 2018 and 71 in 2019. Conclusion: In this case, the improving attorney system was found to be helpful in activating the Quality circle. It is expected to revitalize Korea's Quality circle by spreading the improving attorney system to many companies.