• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.493-502
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• 2019

Maize (Zea mays L.) is a C4-plant and one of the three major crops grown worldwide. Because of its high productivity, maize is considered as one of the most important food and feed stocks in the world. Recently, bioethanol from maize was predominantly generated in the USA and Brazil. Infection of maize by several diseases resulted in a huge disaster and prevented maize production. Downy mildew, caused by Peronosclerospora sorghi, is one of the most serious diseases of maize. Despite efforts to develop downy mildew-resistant cultivars or seed treatment with metalaxyl, downy mildew persists as a serious pathogen and is still prevalent in specific geographical locations. Analysis of soils infected with downy mildew and investigation of candidates associated with downy mildew resistance is an attractive method to overcome downy mildew damage in maize. In a previous study, we reported that maize chromosome 6 carries a possible candidate gene for downy mildew resistance. Using bioinformatics tools and RT-PCR analysis, five novel genes including bZIP, OFP transcription factor, and Ppr were identified as candidate genes associated with downy mildew resistance.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.376-387
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• 2010

Recently, speedy, convenient and easy detection technologies have been developed rapidly and on the contrary, studies on development of traditional detectors applying biochemical characteristics has gradually been decreased. This review examined trend in current studies on detection of food-borne pathogenic microorganisms in the fields of selective media, immuno-assay, Polymerase Chain Reaction (PCR), microarray, terahertz spectroscopy & imagination and so on. Most traditional methods to detect the organisms from food matrix rely on selective media and such a method have disadvantages like long time requirement and distinguishing one species only from each selective medium although they are highly economical. Various new convenient methods such as Enzyme Linked Immuno-sorbent Assay (ELISA), paper-strip kit, fluoroimmunoassay etc. have been developed. The most ideal method for detecting food-borne pathogenic microorganisms in foods should be accurate, convenient, rapid and economical. Additionally, it is needed that capabilities of quantitative analysis and automation to be applied to industries.

• Journal of Korean Home Economics Education Association
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• v.19 no.3
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• pp.119-131
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• 2007

This study was to investigate the recognition level of food safety from high school students(264 male, 276 female) in Chuncheon area using questionnaires. The results of the survey are summarized as follows : Regarding the general consciousness of the conditions of food safety, the proportion of the students who worry about it is higher, while 40.0% respond they are not concerned with it. The information pertinent to food safety was usually acquired from the mass media. As a fundamental reason responsible for the food safety accidents, they pointed out deficient sense of responsibility of the personnels who produce, distribute, and sell food products. As the most problematic materials threatening food safety, they pointed out heavy metals(24.8%), and subsequent responses were environmental hormones(24.4%), food additives(17.0%). The foods, for which they are most concerned about residual pesticides, were vegetables and fruits. High proportion of the students perceived that agricultural products are not safe from residual pesticides, and most of the students(92.4%) thought that residual pesticides are bad for their health. The examination on the food safety influenced by heavy metals reveals that 87.4% of the students thought the materials do influence food safety. As the food kind that is likely to be most polluted by heavy metals, they pointed out fishery products. The highest concern about processed food stuffs was the food additives. Most of the students thought that the containers of processed foods may be toxical. 25% of the students are more seriously considering food safety when they buy foods. High proportion of the students who responded they confirm safety-related matters at the time of food purchase thought much of food safety, while high proportion of those who didn't confirm those matters lay a great importance on the taste.

• 한국지구물리탐사학회:학술대회논문집
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• 2000.09a
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• pp.132-146
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• 2000

Seismic refraction survey was performed for 10 lines along NE-SW and NW-SE directions above Nampoong gallery at Makyo-ri, Dogye, Samcheok, Kangwon-do. 48 geophones were laid in line with the interval of 1m, and a 5Kg hammer was used as a source at 5 points for each line. Data processing was done using reciprocal time method, GRM, and traveltime tomography which utilizes wavefront expansion method for forward process and STRT for inversion. The result shows that the first layer has its lower boundary between 3.49m and 8.88m. The P-wave velocity of the first and the second layer were estimated as 270${\~}$360m/s and 1550${\~}$1940m/s respectively. When the boundary of the first and second layer is smooth enough and the velocity difference is large enough, GRM has little advantage over reciprocal time method. The result of reciprocal method and traveltime tomography shows consistency. The northeast part of the boundary has syncline structure, which is similar to the topography above. This implies that the collapse of the cavities of Nampoong gallery result in the subsidence of the ground surface. The subsidence is in progress across the Youngdong railroad, therefore a proper reinforcement work is required.

• Journal of Plant Biology
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• v.14 no.3
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• pp.36-42
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• 1971

The effects of irregular burning of vegetation by man were studied in relation to composition and productivity in a non-agricultural montane grassland in the Chongsun area, Kangwon-Do, Korea. The floristic composition in all study area includes 38 species. Three of the stations are dominated by Arundinella hirta and one is dominated by Miscanthus sinensis. The standing crop of the first station, which was fired in early spring, 1970, was 358.7g/$m^2$ to 497.5g/$m^2$; that of the second station, fired in late 1969 was 351. 5g/$m^2$; the third station, fired sometime in 1968, had a standing crop of 314.5g/$m^2$ to 397.1/$m^2$; the fourth station, having had no recent fires, had a standing crop of 370.0g/$m^2$ to 448.0g/$m^2$. The daily productivity shows a maximum of 6.03g/$m^2$ in the first station, and a minimum of 0.85g/$m^2$ in the fourth station. The productivity of grassland in the study area is at a maximum during July and August because of much precipitation, and decreases rapidly in the months to follow. The productive structure of the first and fourth stations is shown in Fig. 2 and 3. At the first station the maximum height attained by the plants was 180cm. In the height range of 50cm to 100cm there was a maximum of assimilative organs (5.6g/0.25$m^2$$\times$10cm), while in the height range below 50cm there was a maximum of non-assimilative organs (13.0g/0.25$m^2$$\times$10cm). At the fourth station, which has not been fired recently, the maximum height reached by the plants was commonly below 100cm. The assimilative organs showed a maximum abundance in the height range of 40cm to 50cm (4.5g/0.25$m^2$$\times$10cm). while the non-assimilative organs showed their greated abundance in the height range below 10cm (6.0g/0.25$m^2$$\times$10cm). There was a direct relationship between daily productivity and organic matter, available phosphorous, exchangeable calcium and potassium. It appears that the nutrients provided by the ash created in the firing of the study can be an important factor in the productivity of these grasslands.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.503-507
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• 2015

To examine the interannual variation of seedfall and seed viability rates of Acer pictum subsp. mono (APSM), we investigated the annual seedfall and seed viability of APSM in the natural broadleaved forest in Mt. Jungwang, Gangwon-do, from 2009 to 2014. The amounts of annual seedfalls from 2009 to 2014 were revealed to be 5,700, 4,060, 60,900, 403,450 and 310 ea/ha respectively. 2013 is presumed to be the masting year since large amounts of seedfall were revealed, compared to that of the other years in the study period. Also, the amount of seeds was significantly different among seed viabilities. Most fallen seeds were damaged or decayed, accounting for 47.88% of the total, followed by empty seeds, undeveloped seeds and sound seeds in that order. The percentage of sound seeds ranged from 6.7 to 31.0%, which marks the lowest average with 16.74%. In the masting year, 2013, a significantly larger number of sound seeds fell at 125,070 ea/ha, on the forest floor than in the other years (320~17,840 ea/ha). Meanwhile, the ratio of damaged or decayed seeds was the lowest at 38%, although the number of those seeds was the largest, 153,310 ea/ha, for the same year. These results imply that the surplus seeds are supplied for natural regeneration in the masting year, supporting the seed predator satiation hypothesis. More long-term researches should be conducted on the seed production of broadleaved trees.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.3_4
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• pp.61-71
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• 1995

Natural ground is a composite consisted of the three phases of water, air and soil paircies. Among the three components, water as a material is weU understood but soil particles are not in foundation engineering. Especially, weathered granite soil generally shows a large volumetric expansion when they freeze. And, the stability and durability of the soil have shown decreased with repetitive freezing and thawing processes. These unique charcteristics may cause various construction and management problems if the soil is used as a construction material and foundation layers. This project was initiated to investigate the soil's physical and engineering characteristics resulting from freezing and freezing-thawing processes. Research results may be used as a basic data in solving various problems related to the soil's unique characteristics. The following conclusions were obtained: The degree of decomposition of weathered granite soil in Kangwon-do was very different between the West and East sides of the divide of the Dae-Kwan Ryung. Soil particles distributed wide from very coarse to fine particles. Consistency could be predicted with a function of P200 as LL=0.8 P200+20. Permeability ranged from 10-2 to 10-4cm/sec, moisture content from 15 to 20% and maximum dry density from 1.55 to 1.73 g /cmΥ$^3$ By compaction, soil particles easily crushed, D50 of soil particles decreased and specific surface significantly increased. Shear characteristics varied wide depending on the disturbance of soil. Strain characteristics influenced the soil's dynamic behviour. Elastic failure mode was observed if strain was less than 1O-4/s and plastic failure mode was observed if strain was more than 10-2/s. The elastic wave velocity in the soil rapidly increased if dry density became larger than 1.5 g /cm$^3$ and these values were Vp=250, Vg= 150, respectively. Frost heave ratio was the highest around 0 $^{\circ}C$ and the maximum frost heave pressure was observed when deformation ratio was less than 10% which was the stability state of soil freezing. The state had no relation with frost depth. Over freezing process was observed when drainage or suction freezing process was undergone. Drainage freezing process was observed if freezing velocity was high under confined pressure and suction frost process was occurred if the velocity was low under the same confined process.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.122-128
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• 2005

Contamination levels of total aerobic bacteria, coliforms, Esherichia coli, Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes of Kimbab and its main ingredients sampled from general and specialized restaurants were compared. Total aerobic bacteria and coliform counts of Kimbab samples from both restaurant types were not significantly different (p>0.05), showing approximately $4\;to\;6\;log_{10}CFU/g$. E. coli counts were significantly higher in kimbab from general restaurants ($65%:\;0.7-2.6\;log_{10}CFU/g$) than those from specialized ones ($8.33%:\;0.70log_{10}CFU/g$), whereas those of S. aureus and B. cereus were not significantly different (p>0.05). L. monocytogenes was not detected in all Kimbab samples. These results indicate hygiene of Kimbab and its main ingredients are deleterious. Contamination levels of pathogens determined in the present study may be used as primary data for microbial risk assessment.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.179-186
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• 2015

This study was conducted to understand the characteristics of flowering and the factors affecting fruiting grades of Acer pictum subsp. mono(APSM), We examined the characteristics of flowering and fruiting in various natural APSM forest, and investigated annual fruiting grade, DBH, tree height, number of APSM trees within 30 m on 29 selected trees in the natural broadleaved forest in Mt. Jungwang in Gangwon-do, from 2009 to 2014. APSM has heterodichogamous sexual system consist of protoandry and protogyny. Eight trees have changed their sex morphs; 3 trees change the sex morph PA to PG, and 5 trees does the sex morph PG to PA. Early fall of young ovary is concentrated until early July. Initially, the small samaras are common, and was gradually increased the samaras suffered insect damage. Most flowers of APSM are pollinated by Andrenidae sp., Syrphidae sp. and Tachinidae sp.. Number of early fall samaras and the status of fallen samaras showed a significant difference by the year and region. Corymbose panicle and young leaves developed on the top of APSM twigs. Newly grown opposite twigs of APSM did not grow sufficiently and had no floral buds. The highest fruiting grade of tree was 9.0, and the mean values was only 3.8. The highest fruiting grade of year was 4.55 in 2013, and the lowest did 0.07 in 2014. Highly significantly correlated and regressed between mean of annual fruiting rates and rates of crown under sun light. This results would imply that thinning for tree growth through improved light absorption might be a method to enhance seed production of APSM in the seed production forest.

• Journal of the Ergonomics Society of Korea
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• v.26 no.3
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• pp.91-100
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• 2007

The purposes of this research are to survey work-related risk factors of musculoskeletal disorders(MSDs) in various departments and tasks at general hospitals in non-manufacturing sectors, and to use basic data derived from the survey results in preventing work-related MSDs in hospital workers. Investigation started in March of 2006 and continued for 6 months in 220 general hospitals at Seoul, Incheon, Kyeongi, and Kangwon area. Investigators visited and interviewed workers in hospitals to identify the presence of tasks of musculoskeletal burden, the investigation results of ergonomic risk factors required by the Occupational Safety and Health Law, statistical analysis from questionnaire for musculoskeletal symptoms, and major departments and tasks that have such risk factors. Twenty-seven percents of hospitals finished the investigation of ergonomic risk factors, and 69% did not do the investigation while remained 4% did not have such factors in their hospitals. The rank order of major departments that had such musculoskeletal burdens was kitchen rooms of 143, managing departments/computer rooms/dispensaries of 137, physical treatment rooms of 109, nursing departments of 96, radiological and clinical laboratories of 63. Eighteen hospitals that did not hold legal duties by the section 148 of labor minister decree practiced prevention programs of MSDs according to the labor-management cooperation. Nursing departments ranked in the first place for the numbers of musculoskeletal symptoms of 438. Managing departments/computer rooms/dispensaries, kitchen rooms, and medical treatment departments held 127, 52 and 45 symptoms, respectively. The magnitude order of physical symptom areas followed shoulder of 185, backs and waist of 166, hand wrists of 120, necks of 110, and legs/feet of 106. The departments and jobs that had major work-related ergonomic risks were patient transporting, central supplying, patient nursing (moving patients into wheel-chairs, changing of patient posture and sheet alteration), manual transporting, operation, and managing/computer departments.