• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.274-279
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• 2006

The exact estimation of crop evapotranspiration containing reference or potential evapotranspiration is necessary for decision of crop water requirements. This study was carried out for the evaluation and application of various meteorological elements used for the calculation of reference evapotranspiration (RET) by FAO Penman-Monteith (PM) model. Meteorological elements including temperature, net radiation, soil heat flux, albedo, relative humidity, wind speed measured by meteorological instruments are required for RET calculation by FAO PM model. The average of albedo measured for crop growing period was 0.20, ranging from 0.12 to 0.23, and was slightly lower than 0.23. Determinant coefficients by measured albedo and green grass albedo were 0.97, 0.95 and standard errors were 0.74, 0.80 respectively. Usefulness of deductive regression models was admitted. To assess an influence of soil heat flux (G) on FAO PM, RET with G=0 was compared with RETs using G at 5cm soil depth ($G_{5cm}$) and G at surface ($G_{0cm}$). As the results, RET estimated by G=0 was well agreed with RET calculated by measured G. Therefore, estimated net radiation, G=0 and albedo of green grass could be used for RET calculation by FAO PM.

• Journal of Life Science
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• v.22 no.3
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• pp.366-372
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• 2012

This study was conducted to estimate the extent of linkage disequilibrium (LD) and effective population size using whole genomic single nucleotide polymorphisms (SNP) genotyped by DNA chip in Hanwoo. Using the blood samples of 35 young bulls born from 2005 to 2008 and their progenies (N=253) in a Hanwoo nucleus population collected from Hanwoo Improvement Center, 51,582 SNPs were genotyped using Bovine SNP50 chips. A total of 40,851 SNPs were used in this study after elimination of SNPs with a missing genotyping rate of over 10 percent and monomorphic SNPs (10,730 SNPs). The total autosomal genome length, measured as the sum of the longest syntenic pairs of SNPs by chromosome, was 2,541.6 Mb (Mega base pairs). The average distances of all adjacent pairs by each BTA ranged from 0.55 to 0.74 cM. Decay of LD showed an exponential trend with physical distance. The means of LD ($r^2$) among syntenic SNP pairs were 0.136 at a range of 0-0.1 Mb in physical distance and 0.06 at a range of 0.1-0.2 Mb. When these results were used for Luo's formula, about 2,000 phenotypic records were found to be required to achieve power > 0.9 to detect 5% QTL in the population of Hanwoo. As a result of estimating effective population size by generation in Hanwoo, the estimated effective population size for the current status was 84 heads and the estimate of effective population size for 50 generations of ancestors was 1,150 heads. The average decreasing rates of effective population size by generation were 9.0% at about five generations and 17.3% at the current generation. The main cause of the rapid decrease in effective population size was considered to be the intensive use of a few prominent sires since the application of artificial insemination technology in Korea. To increase and/or sustain the effective population size, the selection of various proven bulls and mating systems that consider genetic diversity are needed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.89-97
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• 2016

This study was carried out to determine the effect of mixed pasture using domestic varieties orchardgrass 'Kodione' and tall fescue 'Purumi' on forage yields and botanical composition from 2013 to 2015 in middle region of Korea. The following mixed pastures were used in this study: treatment A (orchardgrass oriented mixture with imported varieties), treatment B (orchardgrass oriented mixture), treatment C (orchardgrass and tall fescue oriented mixture), treatment D (tall fescue oriented mixture), treatment E (tall fescue oriented mixture without orchardgrass), treatment F (only orchardgrass), and treatment G (only tall fescue). In botanical compositions at last cutting time in 2015, treatment A had orchardgrass at 7.1%, tall fescue at 47.9%, kentucky bluegrass at 15.2% and white clover at 25%. Meanwhile, treatment B had orchardgrass at 25.9%, tall fescue at 47.0%, kentucky bluegrass at 4.9% and white clover at 18.3%. Consequentially, in botanical composition from 2014 to 2015, treatment A was changed more compare to other treatments B, C, D and E. The average of dry matter (DM) yield for 2 years of treatment E (18,369 kg/ha) was the highest among the seven treatments, but there was no significant difference among other treatments except treatment A (p>0.05). The crude protein (CP) and in vitro dry matter digestibility (IVDMD) of treatment A were 14.5% and 74.8%, and treatment E were 14.1% and 73.0%, respectively. The content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were lower in treatment E and A than other treatments, and treatment E showed high content of total digestible nutrient (TDN). Therefore, tall fescue oriented mixture using domestic tall fescue variety Purumi had good forage productivity, quality and botanical composition in middle region of Korea for the establishment of grassland.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.9
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• pp.637-648
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• 2009

As the cost of disks decreases, PCs are soon expected to be equipped with a disk of 1TB or more. Assuming that a single person generates 1GB of data per month, 1TB is enough to store data for the entire lifetime of a person. This has lead to the growth of researches on lifelog management, which manages what people see and listen to in everyday life. Although many different lifelog management systems have been proposed, including those based on the relational data model, based on ontology, and based on file systems, they have all advantages and disadvantages: Those based on the relational data model provide good query processing performance but they do not support complex queries properly; Those based on ontology handle more complex queries but their performances are not satisfactory: Those based on file systems support only keyword queries. Moreover, these systems are lack of support for lifelog group management and do not provide a convenient user interface for modifying and adding tags (metadata) to lifelogs for effective lifelog search. To address these problems, we propose a lifelog management system based on the relational data model. The proposed system models lifelogs by using the relational data model and transforms queries on lifelogs into SQL statements, which results in good query processing performance. It also supports a simplified relationship query that finds a lifelog based on other lifelogs directly related to it, to overcome the disadvantage of not supporting complex queries properly. In addition, the proposed system supports for the management of lifelog groups by providing ways to create, edit, search, play, and share them. Finally, it is equipped with a tagging tool that helps the user to modify and add tags conveniently through the ion of various tags. This paper describes the design and implementation of the proposed system and its various applications.

• Journal of dental hygiene science
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• v.16 no.2
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• pp.142-149
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• 2016

The number of male dental hygienists has been continuously increasing in dental services. The purpose of this study aimed to identify the relationship between job stress, job satisfaction, and turnover intention in male dental hygienists and to provide basic data to improve their job satisfaction. The study population was 110 Korean male dental hygienists working for dental clinics or hospitals. The data were collected from November 10 to December 7, 2015. After an explanation about the objective of the study, 110 questionnaires were distributed via email, and 97 responses were analyzed using SPSS. Overall averages of job stress, job satisfaction and turnover intention in male dental hygienists were 3.05, 2.92, and 3.47 out of 5, respectively. Some sub-factors of job stress, including interpersonal relationships at the workplace and future prospects of dental clinics, were proven to have statistically significant negative influence on job satisfaction (p<0.001). Regression analysis was performed with job stress and job satisfaction as independent variables and turnover intention as a dependent variable. Results showed that job stress had a positive effect on turnover intention (p<0.01) while job satisfaction had a negative effect on turnover intention (p<0.001). Job satisfaction was revealed to have statistically significant negative influence on turnover intention (p<0.001). Some of sub-factors of job stress, including work environment and future prospects of dental clinics and professional position, had a positive effect on turnover intention (p<0.05). The study showed that higher job stress led to higher turnover intention, and higher job satisfaction led to lower turnover intention. Accordingly, job stress and job satisfaction are critical factors for turnover intention in male dental hygienists.

• Therapeutic Science for Rehabilitation
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• v.8 no.4
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• pp.53-63
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• 2019

Objective : Many communication recovery strategies should be used when communication breakdowns occur for successful communication, however, communication problems increase due to inadequate use of such strategies in older people with dementia. The purpose of this study was to investigate the difference of recovery strategy between dementia and the elderly in conversational discourse. Method : The subjects were eight of Alzheimer's dementia and 10 general elderly. Conversation discourse tasks were conducted face-to-face with the subjects. Communication breakdown and communication recovery strategies were analyzed based on 200 utterances collected in the conversation discourse. Result : First, the AD group had more communication breakdown than the control group, but the recovery rate did not differ between the groups. Second, in the AD group, the nonspecific recovery strategy and the clarification demand strategy were used as the expression strategy. The recovery rate after using expressive strategy was more than 90% in explanation strategy, combined strategy, nonspecific repair strategy, and repetition confirmation strategy. The response strategy used a lot of paraphrase strategy and combined strategies, and the recovery rate after using the response strategy was 100% for the simplification strategy, repeat strategy and gesture strategy. Conclusion : The AD group showed more breakdown of research subjects and breakdown of researchers than control group, and it showed ability to use various expression strategy and response strategy though there was difference in repair rate between communication repair strategy. AD group used nonspecific repair strategy in expression strategy the most and paraphrase strategy in response strategy the most. This shows different characteristic from ordinary elderly people. Therefore, it is necessary to utilize this repair strategy for rehabilitation of AD elderly.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.504-515
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• 2021

To examine the relationship between environmental factors influencing the habitat of Aconitum austrokoreense Koidz., this study employed the MexEnt model to evaluate 21 environmental factors. Fourteen environmental factors having an AUC of at least 0.6 were found to be the age of stand, growing stock, altitude, topography, topographic wetness index, solar radiation, soil texture, mean temperature in January, mean temperature in April, mean annual temperature, mean rainfall in January, mean rainfall in August, and mean annual rainfall. Based on the response curves of the 14 descriptive factors, Aconitum austrokoreense Koidz. on the Baekun Mountain were deemed more suitable for sites at an altitude of 600 m or lower, and habitats were not significantly affected by the inclination angle. The preferred conditions were high stand density, sites close to valleys, and distribution in the northwestern direction. Under the five-age class system, the species were more likely to be observed for lower classes. The preferred solar radiation in this study was 1.2 MJ/m². The species were less likely to be observed when the topographic wetness index fell below the reference value of 4.5, and were more likely observed above 7.5 (reference of threshold). Soil analysis showed that Aconitum austrokoreense Koidz. was more likely to thrive in sandy loam than clay. Suitable conditions were a mean January temperature of - 4.4℃ to -2.5℃, mean April temperature of 8.8℃-10.0℃, and mean annual temperature of 9.6℃-11.0℃. Aconitum austrokoreense Koidz. was first observed in sites with a mean annual rainfall of 1,670- 1,720 mm, and a mean August rainfall of at least 350 mm. Therefore, sites with increasing rainfall of up to 390 mm were preferred. The area of potential habitats having distributive significance of 75% or higher was 202 ha, or 1.8% of the area covered in this study.

• Food Engineering Progress
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• v.14 no.2
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• pp.166-172
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• 2010

The extraction of polyphenol and flavonoid from citrus peel was performed by the ethanol, sugar, hot water (80$^{\circ}C$), and subcritical water extraction methods. The maximum yields of total polyphenolic compounds (27.25${\pm}$1.33 mg QE/g DCP, QE and DCP indicate quercetin equivalent and dried citrus peel, respectively) and flavonoids (7.31${\pm}$0.41 mg QE/g DCP) were obtained by subcritical water extraction (SWE) with operating conditions of 190$^{\circ}C$, 1300 psi, and 10 min. The yields by SWE were over 7.2-, and 8.5-fold higher than those of total polyphenols (3.79${\pm}$0.73 mg QE/g DCP) and flavonoids (0.86${\pm}$0.27 mg QE/g DCP) obtained using the ethanol extraction, which showed the highest extraction efficiency among tested conventional methods, respectively. Antioxidant activities of extracts obtained by different methods showed no significant differences. However, the relative antioxidant yield per 1 g dried citrus peel by SWE (190$^{\circ}C$, 10 min) was over 9.5-fold higher than that by the ethanol extraction.

• Food Engineering Progress
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• v.14 no.4
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• pp.335-341
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• 2010

The extraction of polyphenol and flavonoid from black rice bran was performed by diverse extraction methods using the sugar solution, ethanol, hot water ($80^{\circ}C$), and by subcritical water extraction (SWE) method. By SWE under operating conditions of $190^{\circ}C$, 1,300 psi, and 10 min, the maximum yields of total polyphenolic compounds (35.06${\pm}$1.28 mg quercetin equivalent (QE)/g dried material and flavonoids (7.08${\pm}$0.31 mg QE/g dried material) could be obtained. These results were over 11.77- and 12.21-fold higher than those of the ethanol extraction, which showed the highest extraction efficiency among tested conventional methods in total polyphenols (2.98${\pm}$0.74 mg QE/g dried material) and flavonoids (0.58${\pm}$0.21 mg QE/g dried material), respectively. Though the highest antioxidant activity (87.14${\pm}$1.14%) was observed at the dried extract obtained from ethanol method, the relative antioxidant activity per 1 g dried black rice bran by SWE ($190^{\circ}C$, 10 min) was over 11.53-fold higher than that by the ethanol extraction.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.40-49
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• 2010

This study was conducted to examine genetic variation on leaf characteristics of Zelkova serrata populations. Leaf samples were obtained from eighteen populations and fourteen leaf characteristics such as leaf blade length, leaf width, leaf area and etc. were measured. In all leaf characteristics, there were significant differences among populations and among individuals within population. Most variance of leaf characteristics was contributed to among individuals within population except for length from leaf base to maximum width (x3) and the ratio of x3 to leaf blade length (x10). The relatively high variations of leaf characteristics were found at Gurye, Jungeup and Gyungju populations while Youngwol, Cheongsong, Youngchun populations showed the lower variation. There was high correlation among leaf characteristics related to leaf size, but not among the variables of ratio between leaf characteristics. Length from leaf base to maximum width(x3) and the ratio of x3 to x10 showed significant positive correlation with latitude and altitude of populations, which reflect the differences of mean annual temperature among populations. Mean annual rainfall of populations showed negative correlation with leaf blade length, leaf width, length from apex to first serration and leaf area. Four principal components (PC) were deduced from principal component analysis, which explain the 88.5% of total variance of leaf characteristics. Leaf area, length from leaf base to maximum width, serration number and petiole length showed the highest contribution to PC1, PC2, PC3, PC4, respectively. According to cluster analysis, the populations of Z. serrata were divided into two groups, which reflect the difference of mean annual temperature between groups. Within group, however, specific tendency of clustering was not observed among populattions.