• Journal of Korean Society for Atmospheric Environment
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• v.32 no.5
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• pp.513-525
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• 2016

To propose an effective ensemble methods in predicting $PM_{10}$ concentration, six experiments were designed by different ensemble average methods (e.g., non-weighted, single weighted, and cluster weighted methods). The single weighted method was calculated the weighted value using both multiple regression analysis and singular value decomposition and the cluster weighted method was estimated the weighted value based on temperature, relative humidity, and wind component using multiple regression analysis. The effects of ensemble average methods were significantly better in weighted average than non-weight. The results of ensemble experiments using weighted average methods were distinguished according to methods calculating the weighted value. The single weighted average method using multiple regression analysis showed the highest accuracy for hourly $PM_{10}$ concentration, and the cluster weighted average method based on relative humidity showed the highest accuracy for daily mean $PM_{10}$ concentration. However, the result of ensemble spread analysis showed better reliability in the single weighted average method than the cluster weighted average method based on relative humidity. Thus, the single weighted average method was the most effective method in this study case.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.269-278
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• 2022

Recently, the travel and lodging industries have been suffering from the spread of COVID-19. But Airbnb recovered its profits with a differentiated strategy. This study identified the characteristics of Airbnb and examined their effects on customer's revisit intention in the Airbnb context. Perceived value, trust about Airbnb, and social norms were considered as the key factors of revisit intention. In addition, the effects of relative attractiveness, brand identification, and enjoyment on perceived value and trust about Airbnb were examined. The proposed research model was tested based on 285 consumers who had Airbnb experience more than twice. The analysis results showed that relative attractiveness, brand identification, and enjoyment had a significant influence on perceived value and trust. Perceived value had a significant influence on revisit intention. However, trust about Airbnb and social norms did not significantly affect revisit intention. Moreover, ths analysis results found no significant moderating effect of share of wallet. Based on the results of this study, Airbnb would establish effective marketing and operation strategies by understanding the formation mechanism of consumer's revisit intention toward Airbnb.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.2
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• pp.158-163
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• 2020

This study examines and presents reasonable improvement measures for the operation and revision of the relative value scoring system, and the basis for performance of a medical technologist. Seven hospitals were enrolled in the study, and included 5 resident laboratory medicine specialists and 53 medical technologists, giving a ratio of 10.6 technologists per laboratory medicine specialist. The average of professional manpower scores was 18, and the average of each medical institution's total score was 78. Ratings and additional rates were in the range 2~3%, and quality-added ratios were 2~3%, with no significance. Excluding pathological testing and assessing physiological functions, the average number of diagnostic tests for health insurance claims were 9,618,062, including 4,378,146 points for 5% of the total relative value scores. According to the DEA, the appropriate number of medical technologist is one person per 49,974 points of relative value. In conclusion, our study results indicate that it would be desirable to set the appropriate workforce for medical technologist to one person per 50,000 points of relative value. Our data could be used as a basis for enhancing productivity of the workforce and balancing health care resources.

• International Journal of Reliability and Applications
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• v.2 no.3
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• pp.161-187
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• 2001

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms reliability, failure rate, product life, and durability are explained. From the customer's standpoint, the concept of product quality is classified in five factors, according to related technology: performance, reliability, conformance to specifications, customer perception, and fundamentals advantage. The correlation of the five factors for a first-class product is discussed, Since the market share of a company is determined as the competition result of its product value, defined as product quality and price, the market share increase is derived mathematically from the increment of product value. The market share increase, $\Delta$S, can be calculated from the present market share, S, and the oriented relative value increment of new product, R, to the current product in the same company for the same market target: $\Delta$S : $\Delta$(1-S). R/(1+S.R). Finally, the importance of separating warranty cost from the profit equation for the durables is explained.

• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.1-8
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• 2008

Planetary ball mill was used to decrease and control the particle size of excipients. The effects of the weight of sample and the revolution number of mill, and grinding time on the particle size of the ground sample were analyzed by response surface methodology. The optimum conditions for the milling of microcrystalline cellulose were 38.82 g of the weight of sample and 259 rpm of the revolution number of mill, and 45 minutes of grinding time. The predicted value of the particle size at the these conditions was $19.02{\mu}m$, of which the experimental value at the similar conditions was $18.68{\mu}m$. The tensile strength of tablets of single-component powders, such as microcrystalline cellulose, hydroxypropylmethyl cellulose and starch, binary mixtures and ground binary mixtures of these powder were measured at various relative densities. It was found that the logarithm of the tensile strength of the tablets was proportional to the relative density. A simple model, based upon Ryshkewitch-Duckworth equation that was originally proposed for porous materials, has been developed in order to predict the relationship between the tensile strength and relative density of ground binary tablets based on the properties of the constituent single-component powders. The validity of the model has been verified with experimental results for ground binary mixtures. It has demonstrated that this model can well predict the tensile strength of ground binary mixtures based upon the properties of single-component powders, such as true density, and the compositions. When the tensile strength of the mixture of microcrystalline cellulose hydroxypropylmethyl cellulose (90:10) and the ground mixture of them were compared, the tensile strength of the ground mixture decreased widely from 45.3 to 5.6% compared to the mixture in case the relative density of tablets was in the range of $0.7{\sim}0.9$. When the tensile strength of the mixture of microcrystalline cellulose starch (80:20) and the ground mixture of them were compared, the tensile strength of the ground mixture decreased widely from 31.0 to 11.6% compared to the mixture in case the relative density of tablets was in the range of $0.7{\sim}0.9$.

• Journal of Family Resource Management and Policy Review
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• v.18 no.4
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• pp.135-151
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• 2014

This study focused on issues of relative importance to the work and family life of married men. The work was carried out to determine, when men are in any category, how to increase their satisfaction with their work and family life. Data from 896 married men with their youngest children under 18 years of age was collected and analyzed. Cluster analysis was performed to classify the categories depending on the relative importance of work as compared to family life. I obtained four types relating to the relative importance of work compared to family life. The results are as follows. First, the score of subjective balance which was perceived by the men was slightly higher than the normal range, at 3.27 points. Second, work-family negative spillover is bigger than family-work negative spillover. On the other hand, family-work positive spillover is bigger than work-family positive spillover. Third, in the category in which the difference is largest between the relative importance of work and family life, the men crave the value of nonwork. It seems that in order to bring a particular gravity to work, there is a possibility that the areas outside of work will be suppressed. Also, in this category, both the satisfaction of family life and job satisfaction were low; this will be a point to consider when discussing the problem of the balance of work and family.

• Journal of Mushroom
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• v.16 no.4
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• pp.263-266
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• 2018

This study was investigated the growth characteristics of 'Nongjingo' cultivar(Lentinula edodes) according to relative humidity(RH). The color difference of the pileus showed the highest L(Lightness, L) value in RH65 and the a(Redness, a) value in RH95. b(Yellowness, b) values were similar in all treatments. The hardness of pileus is highest at RH95. As the relative humidity increased, the length of pileus and stipe tended to increase. The diameter and thickness of pileus were high at RH95%. The diameter of stipe could not see the big difference in the three treatment groups. This study growth characteristics and yield were increased at higher relative humidity, but quality was decreased. Therefore, must adjust the relative humidity to produce high quality mushrooms.

• Nuclear Engineering and Technology
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• v.29 no.5
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• pp.375-384
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• 1997

Relative power density distributions of the Kori Unit 1 pressurized water reactor are calculated by Monte Carlo modeling with the MCNP code. The Kori Unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starling with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system converges to a k value of 1.00039 $\geq$ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori Unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root moan square error of 2.159%.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.6
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• pp.814-822
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• 2012

To improve the flow and mixing characteristics of marine SCR system, two different mixer including up-down and swirl type mixer were considered. The purpose of this study is to analyse turbulence intensity and uniformity index in detail and to improve the performance of SCR with respect to the mixer structure. The results showed that, the concentration uniformity index is improved by about 5% with the utilization of both mixers in the front of catalyst part. Although the RMS value and relative turbulence intensity increased after the up-down type mixer, it could observed that the value of two parameters decreased with the flow proceeding forward to the downstream. For the case of swirl type mixer, the decrease of RMS value and relative turbulence intensity were relatively smaller than that of up-down type mixer, and uniform distribution of relative turbulence intensity was observed. As a results, it could be concluded that the mixing effects and the distance of the two kinds of mixer were different.

• Journal of Technologic Dentistry
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• v.22 no.1
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• pp.153-178
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• 2000

Dental prosthetic restoration shows a big difference of cost per itemized unit depending on the size of dental labs, facility standard, manpower, and performance. Even the same dental labs have distinctive cost according to manufacturing performance, inflation, and the number of workers. However, in apite of such a change of circumstances, it appears to be quite stable in the relative cost per itemized unit unless the manufacturing trend of particular item changes dramatically. Therefore, if the relative number of cost per itemized unit, which is produced by costing, is indicated, we are able to utilize it effectively as a standard wage estimate. If the wage of dental prosthetic restoration is determined on the basis of cost, it is desirable that the relative value of cost and that of wage are identical. But, by means of comparative analysis, since the relative value of wage reveals mostly lower than that of cost depending on an item, it is considered that the wage is not reflecting the cost approproately. Due to the subdivision and the profession of medical technology, the new development of wage items for dental prosthetic restoration is required. This means that the need for the establishment of new wage items should be presented as the general concept of dental prothetic restroation changes and the level of pathologic technology increases. The current wage structure has differences in the degree of difficulty accroding to unit items and in the cost factors. Nevertheless, the differences are not reflected enough to the wage, so there is potential to lower the medical quality through the use of low-proce materials to avoid the increase of cost and the work process which skips a manufacturing step. The new items of dental prosthetic restoration also increases, but the development of proper numerical value system is not supported. Thus, the right proce is set mostly by applying to the wage of a similar item. Since most wages are established by an individual agreement between the dental clinic institute and the dental labs, the propriety of wage level lacks. Therefore, it is urgent to provide and promote the system of a fair work charge by a standard cost which can be applied to all medical institute.