• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.213-222
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• 2017

Heat treatment of wood is an attractive alternative environmentally-friendly treatment to add value of less valuable woods by improving color, dimensional stability, and natural durability. To improve the color properties of Korean white pine (Pinus koraiensis) and royal paulownia (Pauwlonia tomentosa), we treated the woods at $160^{\circ}C$, $180^{\circ}C$, $200^{\circ}C$, and $220^{\circ}C$ for 2 hours. Color change after heat treatment was evaluated using the CIE-Lab color system and survey was conducted to determine the consumer preferences towards color of heat-treated wood. Lightness ($L^*$) decreased with increasing temperature and the higher degree of change was obtained in royal paulownia. The red/green chromaticity ($a^*$) in both wood decreased after heat treatment at $160^{\circ}C$, and constantly increased after heat treatment at $180^{\circ}C$ to $220^{\circ}C$. Yellow/blue chromaticity ($b^*$) in Korean white pine tended to increase after heat treatment at $160^{\circ}C$, then decreased gradually afterwards. In royal paulownia, $b^*$ values linearly increased with increasing temperature. Overall color change (${\Delta}E^*$) increased with increasing temperature with higher degree obtained in royal paulownia. Samples with the clamps in both wood species showed lower degree of the change in $L^*$, $a^*$, b and ${\Delta}E^*$. The results of the consumer preferences test showed that the darker colors of heat-treated woods were more preferred by consumers compared to the lighter colors of untreated woods. Consequently, heat treatment could enhance the color properties of Korean white pine and royal paulownia woods for value added products.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.109-116
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• 2002

The objective of this study was to know the qualities of soil and shallow groundwater in plastic film house fields around Central Part of Korea. The study was conducted at 11 sites in Suweon, Hwasung, Pyungtaek, Yongin and Chuncheon through May to August in 1999. Soil textures of plastic films house were mainly sandy loam or loam. Electric conductivity and organic matter content of surface soils mostly exceeded the critical levels for crop production. Average concentration of $NO_3-N$ in the sha]low groundwater was 19.1 mg/L, and it reached almost the limiting level of agricultural groundwater quality (20 mg/L). Moreover about 36% of survey sites exceeded the limiting level of agricultural groundwater quality. Sulfate concentrations also at some sites exceeded agricultural groundwater quality limit level (50 mg/L). Nitrate-N, one of the most important factors in the groundwater quality, had positive correlations with other ions in foundwater.

• Applied Biological Chemistry
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• v.9
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• pp.97-104
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• 1968

A survey of the free amino acids and free sugars in the juice of fourteen citrus varieties was made by means of paper chromatography and the pectin content in the rind was detected The results of the survey are summarized as follows. 1) Sixteen aminoacids detecteu in fourteen varieties under the condition of this study were distributed with. different frequency as follow. Proline, gamma-amino-butyric acid, alanine, valine, serine, glutamic acid, aspartic acid (in 14 varieties), lysine(12), leucine threonine(11), isoleucine(10), arginine(9), glycine(6) ${\beta}-alanine$(4) asparagine(3) unknown(2). 2) Proline, gamma-amino-butyric acid were mostly abundant in all varieties and alanine was next in the amount. 3) The varieties in the decreasing order of number of amino acids container were C. grandis madow C. leiocarpa (14 acids), C. sulcata, C. hassaku. native citron, Fortunella japonica(13) C. grandis heiko, C. Tamurana iyo, C. nobilis(12) C. reticulata C. junos(11) C. natsudaidai(10) C. miyakawa unshiu, C. ohali unshiu(9). 4) The varieties which appear to contain all essential amino acids(6 acids)detected were C. grandis madow C. grandis heiko, C. sulcata, C. Tamurana iyo, C. hassaku and native citron, and C. natsudaidai, C. unshiu were the least (1-3 acids). 5) Glucose fructose, sucrose and maltose were detected in all varieties. 6) The pectin content in the rind ranged from 8.64% F.W.(C. junos) up to 17.0% for C, grandis madow and the mean was $11.63{\pm}2.69%$.

• Journal of agriculture & life science
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• v.53 no.1
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• pp.13-21
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• 2019

This study was carried out to acquire basic data for a long-term hydroponic culture through investigating water and inorganic ion uptake characteristics at different EC level of nutrient solution of three tomato varieties. Three different tomato varieties, the European type(cv. Daphnis), the Asian type(cv. Super Doterang) and cherry type(cv. Minichal), were used for the investigation. Also, the deep flow technique(DFT) was applied. The three different electrical conductivity(EC) level(1.0, 2.0, 3.0, and 4.0 dS·m-1) of hydroponic nutrient solution were used as variable. At a high EC level of nutrient solution, the leaf area and fresh weight decreased in the early stage, and its growth(plant height, leaf number, leaf area, fresh-weight) was poor with salt stress. Result showed that the higher the EC level of the nutrient solution, the lesser was water uptake. The water uptake was not significantly different from varieties in the first survey, but In the second survey, the 'Daphnis' did not show a significant decrease in water uptake in the EC level higher than 2.0 dS·m-1., on the other hand, 'Super Doterang' presented very low water uptake. At a low EC level, N, P, and K, were absorbed more than the concentration of the irrigation water, while Ca, Mg, S uptake were low. At a high EC level, almost ions absorbed less than 50% of the initial concentration of irrigation water. Thus, imbalance among ions was severe at low EC level compared to high EC level. 'Daphnis' was a variety that effectively utilize nutrients under nutrient stress, showing high absorption at low concentration condition and low absorption at high concentration condition. However, 'Daphnis' suffered most seriously by absorbing nutrients excessively.

• Research in Plant Disease
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• v.20 no.1
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• pp.8-14
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• 2014

The socio-network activities for regional governments, agricultural research institutes, developing agencies and policy makers of any countries are very crucial and important to take into account the root cause of current problems faced by farmers. The survey was conducted in South Korea during the period January, 2008 to August, 2012 in order to shed light on prevalence of different diseases on watermelon in different regions and to better understand farmers' knowledge and perceptions for following watemelon's growing procedures and practices. A total of 590 cases were reported on 573 watermelon growers with highest 87.1% in Jeonbuk, 4.7% in Jeonnam, and 8.2% in other regions such as Gyeongbuk, Gyeongnam, Chungnam, Gwangju, Gyeonggi, Daegu, Gangwon, Changwon and Seoul. The maximum percentages of cases recorded were related to diseases and insect pest (38.6%) followed by physiological disorder (29.7%), cultural practices (18.8%), soil and fertilizer (9.0%), herbicide (2.9%) and others (1.0%). It was observed that the manifestation aspects of the diseases were changed due to increasing in proportion of 'in-facility' cultivation to 12,995 ha compared to 'open-field' cultivation (2,722 ha). The present survey revealed the necessity to reduce the damages incurred at watermelon farms as soon as possible through the breeding program to develop resistant cultivar, use of pathogen-free propagating plants, and efficient prevention of pathogen by regular monitoring of watermelon plants at farms.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.213-222
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• 2017

Among flies inside mushroom growing rooms in three farms, Lycoriella ingenua and Megaselia tamilnaduensis were the most common and dominant species during Pleurotus ostreatus cultivation in Korea. In the past, generally, during the incubation period, a low density of mushroom flies was observed in all farms. After the first harvest, mushroom flies density tended to increase sharply. However, many mushroom flies were observed in the summer, despite that season corresponds to the incubation period. This is because annual cultivation systems provide a safe overwintering place compared to seasonal selective ones. The ecology of mushroom flies varies greatly according to the cultivation system. We confirmed that a fallow period reduced the density of mushroom flies. From a survey of the three dimensional distribution of mushroom flies in a growing room, we observed that M. tamilnaduensis showed more positive phototaxis and a higher variation per point of capture than that by L. ingenua. Through this study, two mushroom fly species were identified in the survey farms, with markedly different three dimensional distribution patterns.

• Journal of Agricultural Extension & Community Development
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• v.20 no.4
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• pp.1105-1147
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• 2013

To investigate farmers' satisfaction level and factors influencing on various agricultural and rural policies, an interview survey has been carried out in Jeonnam and Jeonbuk agricultural area, and collected 750 survey questionnaires from farmers. Satisfaction level was low in average ranging from 2.71 to 3.09 in five point Likert-scale on 22 agricultural-rural related policies. Ordered logit model results showed that satisfaction level decreased when farmers are older, had higher income, and had higher number of attendance in agricultural education programme. In addition, satisfaction level decreased when farms had main source of income from rice farming, dry-field farming, livestock farming, or facility horticulture. Lower satisfaction level was also related to location of farm. On the contrary, satisfaction level increased when the farmer had greater owned land. Among 22 agricultural and rural policies, practices that farmers prefer include Direct Payment for Rice Farming Income Compensation, Environment-Friendly Farming Service, Farmland Banking Services in order. Since direct payment policies that farmers prefer may not contribute in development of agriculture, policies can induce both farm income and agricultural development may increase farmer satisfaction level and finally resolve the income gap between the urban workers and farmers.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.2
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• pp.74-83
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• 2001

The purpose of this study was investigate to the influence of forest roads characteristics and environment factors on the soil erosion, stability and vegetation survival of cut slope in forest roads. The results obtained could be summarized as follows; 1. The correlated factors between slope erosion and variables in cut slope were altitude, convex, degree of slope, length of slope and soil depth. In the stepwise regression analysis, length of slope and soil hardness was a high significant and its regression equation was given by -89.6136 + 15.0667X14 + 16.6713X15($R^2$ = 0.6712). 2. The main factors influencing the stability of cut slope were significant in order of coverage, middle, convex, length of slope and north, and its discriminant equation was given by -1.019 + 0.064X22 - 0.808X8 - 0.622X24 + 0.742X11 - 0.172X14 - 0.545X6 ($R^2$ = 0.793). 3. The centroids value of discriminant function in the stability and unstability estimated to 1.244 and -1.348, respectively. The boundary value between two groups related to slope stability was -0.1038. The prediction rate of discriminant function for stability evaluation of was as high as 91.3%. 4. The dominant species of invasion vegetation on the cut slope consist with Carex humilis, Agropyron tsukushiense var. transiens, Calamagrostis arundinacea, Miscanthus sinensis var. purpurascens, and Ixeris dentata in survey area. The rate of vegetation invasion more increased by time passed. 5. The life form of invasion vegetation in cut slop showed to $H-D_1-R_{2,3}-e$ type of the hemicryptophyte of dormancy form, dissem inated widely by wind and water of dissminule type, moderate extent and narrowest extent of radicoid type, erect form of growth form. 6. The correlated factors between forest enviroment and coverage appeared north, passage years and middle position of slope at 5% level. The forest environment factors influencing the invasion plants in survey area were shown in order to altitude, passage years, rock(none), forest type(mixed) and stone amount. The regression equation was given by 17.5228 - 0.0911X3 + 3.6189X28 15.8493X22 19.8544X25 + 0.3558X26 ($R^2$ = 0.4026).

• Journal of Agricultural Extension & Community Development
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• v.8 no.1
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• pp.25-40
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• 2001

The purposes of the study were to identify satisfaction and achievement of learning by female learner's characteristics, and to suggest measures to improve quality of education in internet education programs. In order to determine the educational effectiveness associated with the characteristics of learners, this study attempted to employ two way approaches by observing the degree of achievement for learning, which represents an instructor-oriented approach, and the degree of satisfaction for education, which represents a learner-oriented approach to enhance the quality of internet education for female learners. As an approach to evaluate the educational effectiveness, the degree of achievement in learning(Tyler's classical approach), and the degree of satisfaction for education (Scriven's consumer-oriented evaluation model) were utilized. A survey form was developed by the researcher after reviewing the various tools originated from Boshier, Cross, Gagne and Choi, and distributed to a panel of judges that examined the content validity of the instrument. The sample for the study consisted of 160 female learners from three universities in Seoul and capital area, and the survey form was used to collect data for this study. The SPSS WIN program was used in analyzing the data and a series of statistical tests were conducted including frequency, percentile, t-test, ANOVA, correlation, multiple regression, and factor analysis. The statistical significance level was 0.05. The following conclusion were drawn from this study of female internet education. First, it was evident that female internet learners tend to utilize information from internet, and this can be interpreted as participants' positive attitude, and voluntary participation. Second, educational facilities and services should be improved in the future, because the level of satisfaction was low in these areas compared to curriculum and educational methodology. Third, the participating factors influenced by the level of satisfaction for education of learner characteristics were the 'formation of inter-personal relationship and willingness to change' and the 'needs for education on internet', thus appeared that both social and educational needs influenced the level of satisfaction for education. Fourth, the degree of achievement in learning was higher in the order of 1) attitude 2) function 3) knowledge, thus, attitude change was the most important in achievement of learning. Fifth, the individual background that influenced the level of achievement in learning were age and educational experience. As for the individual level of achievement for learning, the younger and more educated group were more satisfied.

• Journal of Agricultural Extension & Community Development
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• v.4 no.1
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• pp.245-255
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• 1997

The objectives of this study were (1) to analyze the degree of rice farmers' knowledge, attitude and practice (KAP) of the Integrated Pest Management (IPM), (2) to determine the related variables for decisions on pest control, and (3) to indicate desirable direction for IPM farmers' field training. The study was carried out through a questionnaire method and sane interviewing survey of 300 rice farmers by the IPM trainers who participated in IPM training in 1994 or 1995. The data were collected from 268 respondents to the questionnaire consisted of KAP and related variables. The major findings of the study were as follows: 1. The KAP score of the farmers concerning IPM were 71 for knowledge, 76.2 for attitude and 74 for practice on average. 2. The KAP score was higher for farmers cultivating larger land size and for those with more participation in IPM training. Also the KAP was higher for the members of the Rural Leaders Association and Future Farmers Association than any other groups. 3. The IPM farmers had strong positive attitudes towards the resistant rice varieties. However, the practical pest control rate of the IPM farmers was low for conservation of natural enemies, timely control following occurrence and plant compensation what few pest were presence in the paddy field. 4. The KAP Score on the economic threshold level and safe pesticide use was relatively low for elder farmers and for those with lower educational background. Most farmers preferred calendar spraying methods for preventive pest control to any other method of pest control. Knowledge was relatively low on pesticide and environmental contamination. 5. Decision making on pest control depends on the extension officer and rural leader's opinion. The survey method for pest occurrence by directly counting pest in the field was only 22.9% among the farmers of this study. 6. Most farmers used pesticide for preventive pest occurrence even when pest didn't occur in their field. The average number of pesticide applications per cropping season in rice field was 3.7 times, and the number of mixed pesticides per application was 4.3 kinds of pesticides. Also 6 recommendations were made in this study for improvement of IPM farmer's training.