• Food Engineering Progress
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• v.13 no.1
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• pp.64-69
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• 2009

From the 25 fresh fruits and vegetable products, 1,250 isolates grown on MRS agar media were screened for the inhibitory activity on the growth of Escherichia coli 0157:H7, Listeria monocytogenes, and Bacillus cereus as well as Lactobacillus plantarum, L. casei, and Lactococcus lactis subsp. lactis. Among them, 607 isolates (49% of total isolates) from 23 different foods produced growth inhibitory activity on the E. coli 0157:H7, L. monocytogenes, or B. cereus. When these isolates were screened for the inhibitory activity on the growth of L. plantarum, L. casei, and Lactococcus lactis subsp., 24 isolates (3% of total isolates) from 7 food samples showed bacteriocin-like activity. These isolates had typical physiological characteristics of lactic acid bacteria, which indicated these isolates were strains of lactic acid bacteria. The inhibitor from 3 out of 24 revealed as nicin. From the RAPD-PCR profiles, 24 strains was classified and it was also indicated that most of the strains isolated from same produce showed similar phylogenetic profile.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.393-403
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• 2018

Bio-aerosols transported by the air have been considered as the major source of dispersal agents that contaminate agricultural products. Unseen fungal spores are known sources of bio-aerosols that harm mushroom and human health during mushroom cultivation. This study was conducted to obtain basic data on the concentration and species distribution of fungi present in the indoor air of oak mushroom cultivation houses in Korea. In 2015 and 2016, we sampled and analyzed indoor airborne fungal spores 21 times from 13 oak mushroom cultivation farms located in six different provinces. The concentration of airborne fungi ranged from $1.30{\times}10^2$ to $1.59{\times}10^4cfu/m^3$. Surprisingly, in 20 sampling cases, the fungal concentration exceeded $500cfu/m^3$, which is recommended as the indoor air quality standard by the Ministry of Environment, Korea. A total of 450 fungi were isolated and identified to belong to 33 genera and 46 species. Among the identified fungi, human pathogens (4 genera and 4 species) and plant pathogens (10 genera and 13 species) were present. In addition, Trichoderma harzianum, Trichoderma atroviride, and Trichoderma longibrachiatum, which are detrimental species that affect mushroom health, were found 17 out of 21 sampling times. Our results provide evidence that indoor air quality should be improved for better management of mushroom cultivation houses.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.233-241
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• 2016

Experiments were carried out to quantify the topographic effects on attenuation of sunshine in complex terrain and the results are expected to help convert the coarse resolution sunshine duration information provided by the Korea Meteorological Administration (KMA) into a detailed map reflecting the terrain characteristics of mountainous watershed. Hourly shaded relief images for one year, each pixel consisting of 0 to 255 brightness value, were constructed by applying techniques of shadow modeling and skyline analysis to the 3m resolution digital elevation model for an experimental watershed on the southern slope of Mt. Jiri in Korea. By using a bimetal sunshine recorder, sunshine duration was measured at three points with different terrain conditions in the watershed from May 15, 2015 to May 14, 2016. The brightness values of the 3 corresponding pixel points on the shaded relief map were extracted and regressed to the measured sunshine duration, resulting in a brightness-sunshine duration response curve for a clear day. We devised a method to calibrate this curve equation according to sky condition categorized by cloud amount and used it to derive an empirical model for estimating sunshine duration over a complex terrain. When the performance of this model was compared with a conventional scheme for estimating sunshine duration over a horizontal plane, the estimation bias was improved remarkably and the root mean square error for daily sunshine hour was 1.7hr, which is a reduction by 37% from the conventional method. In order to apply this model to a given area, the clear-sky sunshine duration of each pixel should be produced on hourly intervals first, by driving the curve equation with the hourly shaded relief image of the area. Next, the cloud effect is corrected by 3-hourly 'sky condition' of the KMA digital forecast products. Finally, daily sunshine hour can be obtained by accumulating the hourly sunshine duration. A detailed sunshine duration distribution of 3m horizontal resolution was obtained by applying this procedure to the experimental watershed.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.2
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• pp.57-72
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• 2018

In order to extract meaningful information from the excellent farming settlement cases of young farmers published by KNCAF, we studied the key words with text mining and created a word cloud for visualization. First, in the text mining results for the entire sample, the words 'CEO', 'corporate executive', 'think', 'self', 'start', 'mind', and 'effort' are the words with high frequency among the top 50 core words. Their ability to think, judge and push ahead with themselves is a result of showing that they have ability of to be managers or managers. And it is a expression of how they manages to achieve their dream without giving up their dream. The high frequency of words such as "father" and "parent" is due to the high ratio of parents' cooperation and succession. Also 'KNCAF', 'university', 'graduation' and 'study' are the results of their high educational awareness, and 'organic farming' and 'eco-friendly' are the result of the interest in eco-friendly agriculture. In addition, words related to the 6th industry such as 'sales' and 'experience' represent their efforts to revitalize farming and fishing villages. Meanwhile, 'internet', 'blog', 'online', 'SNS', 'ICT', 'composite' and 'smart' were not included in the top 50. However, the fact that these words were extracted without omission shows that young farmers are increasingly interested in the scientificization and high-tech of agriculture and fisheries Next, as a result of grouping the top 50 key words by crop, the words 'facilities' in livestock, vegetables and aquatic crops, the words 'equipment' and 'machine' in food crops were extracted as main words. 'Eco-friendly' and 'organic' appeared in vegetable crops and food crops, and 'organic' appeared in fruit crops. The 'worm' of eco-friendly farming method appeared in the food crops, and the 'certification', which means excellent agricultural and marine products, appeared only in the fishery crops. 'Production', which is related to '6th industry', appeared in all crops, 'processing' and 'distribution' appeared in the fruit crops, and 'experience' appeared in the vegetable crops, food crops and fruit crops. To visualize the extracted words by text mining, we created a word cloud with the entire samples and each crop sample. As a result, we were able to judge the meaning of excellent practices, which are unstructured text, by character size.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.132-140
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• 1986

Eighty one products from 36 kinds of vitamin and mineral feed supplement collected during August, 1984 to February, 1985 were examined for microbiological contamination. In addition, 83 strains of coliform isolated from the samples were tested for the resistance to 8 kinds of antimicrobial drugs and distribution of R plasmid. General bacteria were detected in all of samples tested. Bacterial population was varied from less than 10 per gram of the sample to 1,400,000 per gram and 34 (42%) of 81 samples were contaminated with 100 to 1,000 cells per gram. Coliform isolation, which was more frequent in samples with larger number of general bacteria, was possible in 14 (17.3%) out of 81 samples tested and 6 (33.3%) out of 18 companies were coliform positive in their products. Forty one (49.4%) out of 83 coliform isolates were fecal coliform. The frequency of resistant strains was the highest to sulfadimethoxine (Sa) with 92.8% and followed by streptomycin (Sm, 67.5%), tetracycline (Tc, 50.6%), kanamycin (Km, 26.5%), chloramphenicol (Cm, 18.1%) and ampicillin (Am, 15.7%). No strain was resistant to nalidixic acid (Na) and gentamicin (Gm). The resistance frequency of fecal coliform strains were higher compare to non-fecal coliform strains. There were minimum inhibitory concentration (MIC) of $3,200{\mu}g/m{\ell}$ or higher in 7 strains to Am, 3 to Sm and 3 to Km, and 70 strains had MIC of $1,600{\mu}g/m{\ell}$ of higher to Sa while Tc had MICs from $1.6{\mu}g/m{\ell}$ to $400{\mu}g/m{\ell}$. All strains had MICs of $6.3{\mu}g/m{\ell}$ of lower to Na and $3.1{\mu}g/m{\ell}$ of lower to Gm. Seventy nine (95.2%) of 83 strains were resistant to one or more drugs tested. The most frequent resistance patterns were SaSm (14.5%) and followed by SaSmTc(12%), SaSmTcKm(8.4%) SaTc (8.4%) and SaSmKm (7.2%) ; total 19 different patterns were noted. Thirty two (40.5%) of 79 resistant strains were transferred all of a part of their resistance to Escherichia coli ML 1410. The frequency of transferable resistance was high in Am (100%) and Cm (80%) while low in Tc (38.1%), Sa (18.2%), Sm (17.9%) and Km (4.5%).

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.91-104
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• 1996

The viability loss or death of weed seeds buried in soil can be induced by infrared irradiation which has good penetration in moist soil. By using this principle of pre-emergence soil-treatment, the study was carried out to obtain basic information needed to develop the effective weed control method for the production of less polluted agricultural products. An apparatus for irradiating infrared was constructed by using ceramic material with high emissivity. The LPG was used as fuel for producing infrared by heating ceramic material. The soil heated in this study was loam with four levels of moisture contents (0.6, 5.7, 10.7, 15.1 % wb). The temperature distribution was measured at various soil depths when soil with different moisture content was irradiated with infrared for three different times (30, 60, 90 sec). The soil depths with duration time of minimum 3 minutes over $80^{\circ}C$, temperature inducing viability loss of weed seeds, were investigated. When the moisture content of soil was 0.6 and 5.7 % wb, the soil depths which can induce viability loss of weed seeds was greatly increased with increasing irradiation time. However, any depths of soil tested in this study was not reached to the temperature of $80^{\circ}C$ when 30 seconds of irradiation time was applied on soil with moisture content of 10.7 or 15.1 % wb. Generally, the soil depth needed for viability loss of weed seeds was decreased with increasing moisture content of soil. Also, longer irradiation time was required to induce viability loss of weed seeds with increasing moisture content of soil.

• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.5-27
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• 1987

It is widely recognized that primary health care in the community is one of the most important and effective health measures in these days. However, it is reality that unsatisfactory health care system, ineffective utilization of health care by the community people in the rural area are hampering better understanding for primary health care. Therefore promoting health for the rural people and increasing understanding about primary health care, the baseline survey in the community focused in examination for safe community water supply was carried out. The survey was conducted through August 25-31, 1986 in order to find out health problems and relevant factors and to define the demographic characteristics of $^*$Sanpuk village, Kumsa-Myun, Yuju-Gun, Kyunggi-Do, Korea. Household survey was carried out for every home by trained interviewers. The major results are found out as follows : 1) 84.2%(400 houses) of total households were surveyed because 15.8%(75 houses) were unable to survey due to either refusal against interview or absence of family. These 400 households were composed of 1,697 residents(male:830, female 867). Educational level of respondents showed 34.1% as elementary school graduated. Religion distribution showed Buddism(23.8%) as the most dominant. 50.7% of respondents married in the area. 2) Most households(91.5%) have lived in their own house in Sanpuk area. Average family size showed 4.3. More than half of residents(64.2%) have used public supplied water tap. Only 1.5% of the households had a flush toliet. The rest of households have still used primitive insanitary latrines. 3) 32.5% of residents have used gas burner for cooking and for heating in the house, and the coal briquet were used for boiler. Lack of convenient public transportation was the chief complaint for their day life. 4) Each household occupied 1,990 pyungs of rice paddy and 1,170 pyungs of ordinary field in average. Beside farming products, mushroom was the highest product. 5) Sixth percent of households in the survey area regularly participated in community meeting one hand and on the other hand 39.5% never participated. Most of respondents closely contacted with their neighbours and they seemed very friendly each other. 6) The prevalence rate of illness and injury during recent 15 days showed 48.3 per 1,000. The prevalence rate of chronic illnesses during the past one year showed 74 per 1,000. Injury and accident lead the higher portion(22.0%) in the former and in the latter pain(arthritis, back-pain) showed 27.0% as the dominant sickness. 87.8% of the ill residents in the former received medical treatment. As the most frequently utilized medical facility, the clinic or hospital were counted. Among the residents suffering from chronic illnesses, 77.3% in Sanpuk area get some kind of medical treatments and they rarely utilized the clinic or hospital. The reason why the patient did not receive any medical care was found out the fact that symptoms of illness was light or mild and economic problems was serious. 7) Average age of marriage showed 21.6 years old in the women and the average duration of marital period was shown for 15.1 years. The married woman in reproductive age in Sanpuk area had experienced pregnancies 4 times in the aver-age including 0.7 time of pregnancy in average were interrupted by induced abortion and 0.3 time by spontaneous abortion respectively. The practicing rate of the family planning of the married woman during reproductive ages showed 70.7% and the tuballigation was found out as the most frequently used contraceptives. 8) Among woman who has children under 2 years old, 70.0% had received the prenatal care for the last pregnancy. However, the average number of prenatal care visitis per woman showed 3.3 times. Fifty-two % of woman who received the postnatal care for the last delivery showed only 37.5%. 9) Immunization rate of the children under 2 years old showed relatively high and looked successful. The breast feeding for these children showed dominantly in the most. Most of the mothers in Sanpuk area had started the supplementary diet during weaning period of their infants of 6th and 7th month after birth. * : Sanpuk area is a demstration area for community development which has been supported by the Community Development Foundation during the part 10 years. The village is relatively closer to urban area such as Seoul, However, it has a similar characteristics shown as a remote village because of geographical location and inconvenient transportation at present.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.269-277
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• 2011

Recent outbreak of new diseases and pests which were introduced from abroad, seriously hampered both quality and safety of paprika fruits. This study has been carried out to aid an establishment of guideline for safe use of pesticides and reduction of their residues on paprika. Systemic fungicides boscalid and pyraclostrobin of either mixed (a.i.; 13.6+6.8%) or single (a.i.; 47 and 18.8%, respectively) water dispersible granule formulation(WG) products were sprayed with recommended or double dosage on paprika grown in green house at March and June. To draw pre-harvest residue limit, residues of each fungicide were analyzed from fruits collected eight times from 18 to 1 day pre-harvest. The biological half-lives of both boscalid and pyraclostrobin in mixed formulation in March and June were slightly shorter than those of single formulation which ranged from 14.4 to 20.1 days. Residue levels of both fungicides of single formulation in fruits in June were about one lower compared to those in March. However, application of double dosage frequently exceeded MRLs from fruits grown both seasons. These results showed that residue levels on fruits persisted longer period of time, more than two weeks, and so the case applied in winter season. The dissipation of fungicides on leaves and fruits was compared. The distribution of both fungicides in leaves was 20-200 times higher than that of fruits and persisted up to 18 days of pre-harvest period at the concentration of 10-40 ${\mu}g\;g^{-1}$. This study indicated that the mixed formulation product exhibited low residues in fruits, but high and long enough to pathogen growth in leaves.

• Journal of Mushroom
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• v.12 no.1
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• pp.67-72
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• 2014

This study was carried out to provide standardization for mushroom production of high quality at farmhouse. The standardization does much to improve merchantable quality, distribution efficiency and fair dealings by shipping of the standard agricultural products. Therefore, modification of these standards is required to fit farmhouse situations. The standardization for production of Pleurotus eryngii of high quality follows like this. A grades were above 90 g at average weight, more 50 mm at stipe thick, 1.6~1.7 at stipe length/stipe thick rate and 1.1~1.2 at pileus diameter/stipe thick ratio. B grades were more 45 g at average weight, above 40 mm at stipe thick, 1.8~1.9 at stipe length/stipe thick ratio and 1.2~1.4 at pileus diameter/stipe thick ratio.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.147-154
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• 1984

Two Fe-hydrous oxide A,B and one Al-hydroxide minerals were synthesized precipitating Fe $Cl_3$ and $AlCl_3$ with alkali solution(NaOH) at pH 6.0, 12.0 and 4.5 respectively, for precise understanding of physico-chemical and surface charge characteristics of soils in which these minerals are dominant. Identification of these final products, effect of free and amorphous materials on X-ray diffraction analysis, particle size distribution and surface change characterics of these minerals were performed. Fe-hydroxide A and B were identified as great deal of X-ray amorphous material and as goethite with large amount of X-ray amorphous material, respectively. Dehydration by oven at $105^{\circ}C$ of these minerals exhibited akaganeite peaks with low X-ray amorphous hump and pure goethite peaks for Fe-hydroxide A and B, respectively. Both minerals, however, turned into hematite upon firing at $550^{\circ}C$. On the other hand, Al-hydroxide identified as mixture of gibbsite and bayerite of around 7:3 ratio. Application of sodium dithionite and ammonium oxalate solutions for removal of free or amorphous Fe and Al from these minerals revealed that only peak intensities of Al-hydroxide system were enhanced upon Al-extraction by oxalate solution even though dithionite solution was much powerful to extract Fe from Fe-hydrous oxide systems. Original(wet) Fe-hydrous oxide A has the highest specific surface and surface charge development(negative and positive), and the greatest amount of less than $2{\mu}m$ sized particles. Specific surface and clay sized particles(less than $2{\mu}m$) of Fe-hydrous oxide A, however, were drastically reduced upon dehydration($P_2O_5$ and oven drying) compare to the rest minerals. The Z.P.C. of these synthetic minerals were 8.0-8.5, 7.5-8.0 and 5.5-6.0 for Fe-hydrous oxide A, B and Al-hydroxide, respectively.