• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.7
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• pp.380-394
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• 2015

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

• Food Science and Preservation
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• v.19 no.3
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• pp.337-343
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• 2012

The objective of this study was to characterize three different commercial (A, B and C) and two handmade (HM-AP, atmospheric pressure; HM-RP, reduced pressure) strawberry jams in relation to soluble solids, pH, total acid, total polyphenol, anthocyanin, color values, texture properties, and sensory evaluation. The soluble solid contents varied from 62.33 to 68.33 $^{\circ}Brix$, and the pH ranged from 3.59 to 3.70. The color L and a values were the highest in the HM-RP strawberry jam (p<0.05). The total polyphenol contents of commercial jams A, B, and C were 56.10, 97.59, and 105.85 mg GAE/100 g, respectively, and those of the HM-AP and HM-RP of handmade jams were 156.13 and 189.94 mg GAE/100 g. The anthocyanin contents of A, B, and C commercial jams were 1.51, 0.95, and 0.80 mg/100 g, respectively, and those of the HM-AP and HM-RP handmade jams were 2.64 and 9.16 mg/100 g. The phenolic contents of the HM-RP jam were significantly much higher than those of the other jams. The hardness ranged from $5.67{\times}10^3$ (HM-AP jam) to $41.91{\times}10^3$ (jam B) dyne/$cm^2$, the jelly strength ranged from 40.08 (HM-AP jam) to 180.33 (jam B) dyne, and the strength ranged from 83.84 (jam C) to 302.93 (jam B) g. The sensory evaluation of the color, flavor, sweetness, sourness, viscosity and overall acceptability of the HM-RP jam showed higher values than those of the other jams. Especially, the highest value of the color score was found in the HM-RP jam. The electon donating abilities of jams A, B, and C and of the HM-AP and HM-RP jams were 44.27, 41.70, 53.06, 69.08, and 73.21%, respectively. These results indicated that the HM-RP strawberry jam prepared with reduced pressure using micro-oxygen technology was a good source of phenolic compounds, total polyphenols and anthocyanin, and had a high level of antioxidant activity.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.403-409
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• 2010

The purpose of this study was to examine the teaching efficiency of clinical training for dental hygiene students in Gyeonggi Province. The subjects in this study were 371 dental hygiene juniors in seven different colleges in Gyeonggi Province, on whom a self-administered survey was conducted. The collected data were analyzed with a SPSS WIN 12.0 program, and the findings of the study were as follows: 1. The teaching efficiency of clinical training that the dental hygiene students undergone was on the average. As for evaluation of the factors of teaching efficiency, they gave the highest marks to the role model factor(3.40). 2. The size of the institutions where they received clinical training made no statistically significant differences to the teaching efficiency of their clinical training. The university hospitals ranked first in professional knowledge, one of the sub-directory of teaching efficiency, and the gap between them and the others was statistically significant(p=.005). 3. Concerning links between satisfaction level with the major and view of teaching efficiency, stronger satisfaction with the major led to better perception of teaching efficiency(p=.001). Among the subdirectory of teaching efficiency, that made statistically significant differences to view of interpersonal skills, performance as a supporter, fair evaluation, academic organization skills(p=.005), encouragement and support, teaching methods, professional academic knowledge(p=.001), communicative competency, performance as a role model and cooperation with the staff of dental clinics(p=.000). 4. There were no statistically significant gaps in teaching efficiency according to teaching styles. Among the sub-directory of teaching efficiency, statistically significant differences were found only in encouragement and support(p=.005). The above-mentioned findings suggest that the teaching efficacy of the clinical training was approximately on the average, and that a better satisfaction with the major led to a higher teaching efficacy. Therefore a wide variety of teaching methods and systematic training programs should be developed to boost the quality of clinical training to improve its teaching efficacy.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.174-180
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• 2000

This work was carried out to investigate the effects of mashing proportion of meju(as wet weight basis of raw soybean) to 20% salt brine on the chemical compositions and sensory characteristics of kanjang. By increasing the salt brine proportion in the kanjang mash, total nitrogen, TCA soluble nitrogen and total free amino acid content in kanjang were decreased accordingly, but although pH values and organic acids content were not different noticeably, the major organic acids in kanjang, lactic acid, pyroglutamic acid and acetic acid were increased up to the mashing proportion of 1:2 from 1:1 and pH values decreased up to that of 1:2.5. Residual sugar content in 1:1 kanjang was exceptionally high. The major free amino acids in kanjang were glutamic acid, lysine, alanine and leucine. The acceptability scores of kanjang tested by sensory evaluation were decreased in inverse proportion to the salt brine proportion of kanjang mash, but those of kanjang samples with $1:1{\sim}1:2.5$ mashing proportions were not significantly different but that of 1:3 different from 1:1 statistically at 5% level. The major chemical compositions, significantly effective to the acceptability of kanjang, were found to be glutamic acid and free amino acid by statistical analysis.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.106-110
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• 2009

In order to reduce the bitter taste and improve the bioavailability of red ginseng extract(RGE), inclusion complexes (RGE-CD) of the extract with ${\alpha}-,\;{\beta}-,\;{\gamma}$-cyclodextrin were prepared and studied for their sensory quality and bioavailability compared to RGE. By complexation, the bitter taste-reducing efficacies of ${\alpha}$-CD and ${\beta}$-CD were much lower than that of ${\gamma}$-CD. In comparative sensory analysis for the bitter taste, RGE-${\gamma}$-CD10, prepared using 10%(w/w) of ${\gamma}$-CD, showed a score of 1.93(decreased by about 78%) compared to RGE as the control. In addition, in sensory analysis for flavor, RGE-${\gamma}$-CD10showed a score of 5.60. Upon increasing the amount of ${\gamma}$-CD to 15%(w/w) and 20%(w/w), respectively, the bitter taste of RGE-${\gamma}$-CD was removed and the flavor of RGE disappeared(scores of 2.67 and 1.67, respectively). Therefore RGE-${\gamma}$-CD10 was chosen as an optimum. The same dosages of RGE and RGE-${\gamma}$-CD10 were orally administered to SD(Sprague-Dawley) rats on a saponin basis, and the plasma concentrations of ginsenoside Rg1 and Rb1 were measured over time to estimate the average AUC(area under the plasma concentration versus time curve) of the ginsenosides. After the oral administration, there were no significant differences in the AUC values of the RGE and RGE-${\gamma}$-CD 10 groups for ginsenoside Rg1. However, AUC values for ginsenoside Rb1 were $25.8{\mu}g{\cdot}hr/mL$ in the RGE group and $81.5{\mu}g{\cdot}hr/mL$ in the RGE-${\gamma}$-CD 10 group, respectively. Therefore, the bioavailability of ginsenoside Rb1 in the RGE-${\gamma}$-CD 10 group was significantly higher by up to 315% compared with that in the RGE group(p = 0.0029). These results show that the bitter taste of RGE can be simultaneously removed by the complexation of RGE and ${\gamma}$-CD(RGE-${\gamma}$-CD) along with increased bioavailability.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.111-119
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• 2014

This study was carried out to investigate the quality characteristics and antioxidant activity of a functional drink prepared by mixed fermentation of oak mushroom extract and whey. As the ratio of oak mushroom extract increased, the pH value of the whey fermentative solution decreased proportionally, and the titratable acidity increased significantly. The number of lactic acid bacteria after 24 hours of culture was at a level of $10^{11}CFU/mL$ in all whey fermentative solutions containing oak mushroom extracts. DPPH and ABTS radical scavenging activities after 24 hours of culture were higher in a fermentative solution containing oak mushroom extract than in the control. After 24 hours of culture, the nitric oxide production in whey fermentation solution by LPS-induced RAW 264.7 cells was lower compared to that in whey fermentation solution with oak mushroom. Sensory evaluation revealed that, color, flavor, taste, and overall acceptability of the whey fermentation solution sample, which contained 1.0% oak mushroom extract, were much better than those of the other groups. Sensory evaluation of a whey drink containing oak mushroom flavor indicated that the whey drink containing 0.001% oak mushroom flavor was better than the other samples.

• Journal of Intelligence and Information Systems
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• v.21 no.3
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• pp.101-116
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• 2015

Recently, due to the development of smart devices and social media, vast amounts of information with the various forms were accumulated. Particularly, considerable research efforts are being directed towards analyzing unstructured big data to resolve various social problems. Accordingly, focus of data-driven decision-making is being moved from structured data analysis to unstructured one. Also, in the field of recommendation system, which is the typical area of data-driven decision-making, the need of using unstructured data has been steadily increased to improve system performance. Approaches to improve the performance of recommendation systems can be found in two aspects- improving algorithms and acquiring useful data with high quality. Traditionally, most efforts to improve the performance of recommendation system were made by the former approach, while the latter approach has not attracted much attention relatively. In this sense, efforts to utilize unstructured data from variable sources are very timely and necessary. Particularly, as the interests of users are directly connected with their needs, identifying the interests of the user through unstructured big data analysis can be a crew for improving performance of recommendation systems. In this sense, this study proposes the methodology of improving recommendation system by measuring interests of the user. Specially, this study proposes the method to quantify interests of the user by analyzing user's internet usage patterns, and to predict user's repurchase based upon the discovered preferences. There are two important modules in this study. The first module predicts repurchase probability of each category through analyzing users' purchase history. We include the first module to our research scope for comparing the accuracy of traditional purchase-based prediction model to our new model presented in the second module. This procedure extracts purchase history of users. The core part of our methodology is in the second module. This module extracts users' interests by analyzing news articles the users have read. The second module constructs a correspondence matrix between topics and news articles by performing topic modeling on real world news articles. And then, the module analyzes users' news access patterns and then constructs a correspondence matrix between articles and users. After that, by merging the results of the previous processes in the second module, we can obtain a correspondence matrix between users and topics. This matrix describes users' interests in a structured manner. Finally, by using the matrix, the second module builds a model for predicting repurchase probability of each category. In this paper, we also provide experimental results of our performance evaluation. The outline of data used our experiments is as follows. We acquired web transaction data of 5,000 panels from a company that is specialized to analyzing ranks of internet sites. At first we extracted 15,000 URLs of news articles published from July 2012 to June 2013 from the original data and we crawled main contents of the news articles. After that we selected 2,615 users who have read at least one of the extracted news articles. Among the 2,615 users, we discovered that the number of target users who purchase at least one items from our target shopping mall 'G' is 359. In the experiments, we analyzed purchase history and news access records of the 359 internet users. From the performance evaluation, we found that our prediction model using both users' interests and purchase history outperforms a prediction model using only users' purchase history from a view point of misclassification ratio. In detail, our model outperformed the traditional one in appliance, beauty, computer, culture, digital, fashion, and sports categories when artificial neural network based models were used. Similarly, our model outperformed the traditional one in beauty, computer, digital, fashion, food, and furniture categories when decision tree based models were used although the improvement is very small.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.1
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• pp.3-11
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• 2015

Purpose It is hard to obtain high quality images of knee and T.M joint because of a lot of soft tissues in the knee and T.M joint area. Most conventional system for high resolution scintigraphy was used by 4 mm aperture pinhole collimator. Performance comparison of high-resolution pinhole SPECT for Micro deluxe phantom using conventional system. the aim of this study is to evaluate performance of each aperture according to the diameter size and the usefulness of 24-hour delayed bone scintigraphy. Materials and Methods In this study 6 mm, 8 mm diameter pinhole collimators were mounted on Siemens E.CAM systems. In order to evaluate performance evaluation of each aperture and Micro Deluxe phantom was used for performance comparison of conventional SPECT system, Projection data were obtained with 9 degree increment per 30 second. Transverse images were reconstructed using dedicated OSEM algorithm with recovery of detector blurring. $^{99m}Tc-HDP$ source was used for 24-hour delayed bone scintigraphy. Results The knee joint images obtained with 24-hour delay were improved more than those obtained with 3-hour delay in our study. The 6 mm and 8 mm pinhole collimators FWHM have improved by 28% SNR and Uniformity have improved by 35%, Contrast has improved by 7% in 24-hour delayed knee joint image. While in 24-hour delayed T.M joint image of the 6 mm and 8 mm pinhole collimators FWHM have decreased by 60% SNR has decreased by 20% and Uniformity has decreased by 25%, Contrast has decreased significantly. Conclusion Pinhole collimators with 6 mm and 8 mm diameter could offer a superior performance for 24-hour delayed bone scintigraphy. The use of 24-hour delayed image provides additional benefits for pinhole scintigraphy of knee joint. Therefore, we expect that it is useful for precise diagnosis of knee joint and it is applicable to others joint imaging.

• Journal of Hospice and Palliative Care
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• v.14 no.4
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• pp.212-217
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• 2011

Purpose: Since 2005, the Ministry of Health & Welfare has provided financial support to promote palliative care for terminal cancer patients. We analyzed how palliative care facilities used the funding between 2006 and 2010. Methods: Frequency analysis was conducted by the item of expenditure based on fiscal reports of the palliative care facilities. Linear regression analysis was performed to examine a trend over time. Kruskal-Wallis test and Wilcoxon rank-sum test were used to compare expenditure items, the number of provision of financial support and type of palliative care units. Results: About a half of the fund was spent to pay care givers salary, improve facilities and purchase equipment regardless of the year, the number of financial support provided or facility type. By year, the operation cost for palliative care program and the education cost for health care workers have significantly increased in linear regression analysis (P<0.01). However, the amount of financial support for the low income group has decreased over years (P=0.024). This trend was affected by evaluation criteria and weight. Conclusion: The government aid for palliative care units has been used to improve facilities and equipment. Moreover, desirable changes were noted such as a higher portion of expenses for program operation and care giver training to enhance the quality of care. However, the evaluation criteria need to be adjusted to prevent any further decrease in the support provided to the low income group.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.617-624
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• 2002

Health drinks were prepared with freeze dried powder of 60% ethanol extract (60% EFDP), 60% ethanol extract after hydrolysis with amyloglucosidase (60% AEFDP) and 80% ethanol extract (80% EFDP) from roasted safflower seed. Quality characteristics and antioxidative properties were investigated. Yield of freeze dried powders were ranged in $4.67%{\sim}5.62%$. Brix, pH and titratable acidity of safflower drinks were ranged in $11.4{\sim}14.2%$, $2.83{\sim}3.34$ and $0.09{\sim}0.91%$, respectively. Content of total phenolic compounds was much more in 80% EFDP (117 mg/g) and safflower drink-I (SD-I, 440 ppm) than others. Content of total flavonoid was observed in higher level in 60% EFDP (49 mg/g) and safflower drink-V (SD-V, 138 ppm) than others. Antioxidant compounds such as N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]ferulamide(serotonin-I) and N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide(serotonin-II) exhibited higher contents of 21.09 ppm, 33.56 ppm in 60% EFDP and of 3.83 ppm, 5.81 ppm in safflower drink-II (SD-II) than others. Content of acacetin was much more in 80% EFDP (13.53 ppm) and safflower drink-IV (SD-IV, 1.14 ppm) than others. From the DPPH test to measure antioxidant activity, it was shown that 80% EFDP and SD-I have stronger scavenging activities of 94.58% and 94.88%, respectively, while BHA standard solution does 93.88%. Among drinks, SD-II was revealed to have highest level on overall acceptance, color and flavor through sensory evaluation. These results induced that safflower seed can be used as natural antioxidant and functional food material.