• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.42-50
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• 1985

The vegetation of common Cryptomeria (Cryptomeria japonica D. Don) stands planted in Chonnam- province was investigated to obtain the fundamental informations for evaluation of suitable site and the improvement of managing method of the Cryptomeria stands in this region. The results investigated were summarized as follows; 1) The growth condition of common Cryptomeria planted 21-25-year-old stands was similar that of same species growing in Akidaken-district in Japan, while the growth condition of 51-58-year-old stands was not so good as that of Japanese. 2) Total number of plant species was 256. The number of floristic composition varied in the range of 42-99- species, which should be mere than those of Japanese. 3) The investigated sites were located in temperate southern part and in subtropic northern part of Korean peninsular. The types of understory vegetation were classified from I to IV class. 4) From the results of high max. possible diversity (H' max), and dominance (1-J') and from the low simple dominance (${\lambda}$) and evenness (J'), It could be concluded that vegetation was relatively in evenness. 5) From the low percent similarity, the specificity among the stands could be evaluated as considerable. 6) After the index of Morista, the 8th stand in Chang sung showed the generalized vegetation, while the 12th stand in Chang hung showed the specialized vegetation. 7) From the low values of Sneath-Sokal distance, the similarity among the stands investigated appeared very high.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.43-49
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• 2015

This experiment was conducted to evaluate the agronomic characteristics and forage productivity of Italian ryegrass cultivars in Yecheon, Kyeongbuk from 2011 to 2013. The experimental design was a randomized complete block design (RCBD) with three replications. Italian ryegrass cultivars were seeded on Sep. 26 in 2011 and Sep. 25 in 2012. The Italian ryegrass cultivars were harvested on the heading date of the variety. The cold-resistance of domestic cultivars was stronger than other foreign varieties. Among early-maturing cultivars, the dry matter (DM) yield of the "Kowinearly" was 10,031 kg/ha, which was significantly higher than that of other cultivars (p<0.05). In medium-maturing cultivars, the DM yield of the "Kowinmaster" and "Tam 90" were 10,484 and 8,191 kg/ha, respectively. Of the two, the former's DM yield was higher than the latter's (p<0.05). Among late-maturing cultivars, the DM yield of "Hwasan 104" was 10,641 kg/ha, which was similar to that of "Hwasan 101" and significantly higher than the other late-maturing cultivars (p<0.05). According to the results obtained from this study, an early-maturing variety with cold-tolerance and high productivity is required for the paddy field cultivation of an Italian ryegrass cultivar after rice harvest in the mid-northern region of Korea. A medium- or late-maturing variety is more advantageous for the field cultivation of the maximum quantity that is possible. In conclusion, to select which variety/ies to grow, the climate of the growing area, weather conditions, and the cropping system must all be considered.

• Fire Science and Engineering
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• v.31 no.2
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• pp.106-112
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• 2017

This study examined the burnout intermediates between Fire officials' job stress and Ego-resilience. The objective of this study is to suggest a policy that improves Fire officials' Ego-resilience. This survey was given to 365 fire officials in northern Gyeonggi-do region and the data was analyzed by correlation analysis and regression analysis using SPPS 22.0. The hypothesis is the Fire officials' burnout would be related to Ego-resilience and the effect on Fire officials' job stress regarding Ego-resilience is associated with burnout. The results of the study are that unstable work and inadequate reward affect the measure of burnout, which manifests as sarcasm and job efficacy and reduces the Fire officials' Ego-resilience that results in a positive pointing of the future, emotion control and interest. The meaning of policy is as follows: First, Fire officials need to be given confidence in their work stability. Second, they have to receive social or financial rewards. Third, they require a continuous supporting policy that solves their tension, physical and mental fatigue. Finally, developing diverse educational programs will be needed to promote their Ego-resilience.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.328-332
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• 1998

This study was carried out to investigate the occurrence and ecological characteristics of Ostrinia furnacalis(Guenee) in Yonchon, northern part of Kyonggi province, where it is main production region of adlay in Korea. The Asian corn borer in adlay field had three generations a year. The first stage of adult activity was greatest from middle May to late June, the second from late July to middle August and the third from late August to middle September. The egg period was $3{\sim}4$ days. The longevity of adult was $7{\sim}11$ days. The days of each development stage from egg to adult were $51{\sim}61$, $33{\sim}42$ and $29{\sim}37$ days in 1st, 2nd and 3rd generations, respectively. The overwintering stage of Asian corn borer was the last instar larvae and it overwintered in the adlay stubbles.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.4
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• pp.255-265
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• 2013

In the coastal region of Korea, historical tide harmonic constants were collected. Long-term tides and short-term tides observed by the KHOA were analyzed by a tide harmonic analysis method. Based on the harmonic constants, tidal characteristics such as tide asymmetry in Korean coastal waters were investigated. The harmonic constants obtained from the long-term tide data in the western coast have been used to show the relation between tide variation and reclamation project. $M_2$ amplitudes in the western coast have been decreased and $M_2$ phases were faster. $M_4$ amplitudes also were reduced and $M_4$ phases were faster in overall. In Mokpo and Kunsan tidal nonlinearity is relatively conspicuous. Overall, non-linearity of tidal currents is higher in the tidal channels flowing fast. The tidal non-linearity has increased by the development projects including large reclamation. The flood dominant characteristic in the northern and central part of Korean western coastal waters and the ebb dominant characteristic in the southern part have been intensified. The construction of Saemangeum sea dike has significantly changed the tidal characteristic in Korean western coastal waters.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.3
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• pp.295-303
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• 2012

Clarify wind energy productivity depends on three factors: the wind probability density function(PDF), the turbine's power curve, and the air density. The wind PDF gives the probability that a variable will take on the wind speed value. Wind shear refers to the change in wind speed with height above ground. The wind speed tends to increase with the height above ground. also, Wind PDF refers to the change with height above ground. Wind analysts typically use the Weibull distribution to characterize the breadth of the distribution of wind speeds. The Weibull distribution has the two-parameter: the scale factor c and the shape factor k. We can use a linear least squares algorithm(or Ln-least method) and moment method to fit a Weibull distribution to measured wind speed data which data was located same site and different height. In this study, find that the scale factor is related to the average wind speed than the shape factor. and also different types of terrain are characterized by different the scale factor slop with height above ground. The gross turbine power output (before accounting for losses) was caculated the power curve whose corresponding air density is closest to the air density. and air desity was choose two way. one is the pressure of the International Standard Atmosphere up to an elevation, the other is the measured air pressure and temperature to calculate the air density. and then each power output was compared.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.1
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• pp.50-56
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• 2020

The field experiment was carried out to evaluate changes of dry matter productivity and feed value of Italian ryegrass and triticale at different growth stages in Wonju from 2018 to 2019. Italian ryegrass and triticale forages were harvested at an interval of seven days from May to June. The dry matter yield of Italian ryegrass with 7,870 kg/ha harvested on May 16 was significantly higher than that harvested on May 3 and May 9. The dry matter yield of triticale with 12,050 kg/ha harvested on June 7 was significantly higher than that harvested from May 3 to May 16. The crude protein yields harvested on May 16 were 890 kg/ha for Italian ryegrass and 1,103 kg/ha for triticale and were significantly higher than those harvested on May 3 and May 9. The total digestible nutrient yield(TDN) of Italian ryegrass with 5,223 kg/ha harvested on May 16 was significantly higher than that harvested on May 3 and May 9. The total digestible nutrient yield of triticale with 8,277 kg/ha harvested on June 7 was significantly higher than that harvested during May, but not different from that harvested after June 7. Considering the dry matter yield, crude protein yield and total digestible nutrient yield, it is suggested that the optimal harvesting times for Italian ryegrass and triticale seem to be May 16 and June 7, respectively.

• Analytical Science and Technology
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• v.26 no.5
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• pp.315-325
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• 2013

The possibility of acute hepatotoxicity caused by dimethylformamide (DMF) requires regular monitoring of the workers who are using DMF to prevent the occupational disease. The authors performed ambient and biological monitoring of workers involved in synthetic leather manufacturing processes using DMF to assess the correlation between the markers of ambient and biological monitoring of DMF. The authors monitored 142 workers occupationally exposed to DMF from 19 workshops in the synthetic leather and ink manufacturing industries located in northern region of Gyeonggi-do. The subjects answered questionnaire on work procedure and use of personal protective equipment to be classified by exposure type. DMF in air samples collected using personal air samplers, diffusive and active sampler, was analysed using gas chromatograph-flame ionization detector (GC-FID) with DB-FFAP column (length 30 m, i.d. 0.25 mm, film thickness 0.25 ${\mu}m$). Urinary N-methylformamide (NMF) was analysed using gas chromatograph-mass selective detector (GC-MSD) at selected ion monitoring (SIM) mode with DB-624 column (length 60 m, i.d. 0.25 mm, film thickness 1.40 ${\mu}m$). Geometric mean (GM) and geometric standard deviation (GSD) of the ambient DMF was $6.85{\pm}3.43$ ppm, and GM and GSD of urinary NMF was $42.3{\pm}2.7$ mg/L. The ratio of subjects with DMF level over 10 ppm was 44%, and those with urinary NMF over 15 mg/L was 87%. NMF in urine adjusted by DMF in air was $4.61{\pm}2.57$ mg/L/ppm and $9.50{\pm}2.41$ mg/L/ppm, respectively, with or without respirator. There was seasonal differences of NMF in urine adjusted by DMF in air, $7.63{\pm}2.74$ mg/L/ppm in summer and $4.53{\pm}2.29$ mg/L/ppm in winter. The urinary NMF concentration which corresponds to 10 ppm of ambient DMF was 52.7 mg/L (r=0.650, n=128). Considering the difference of the route of exposure which resulted from the compliance of wearing personal protective equipment, the estimated contribution of respiratory and dermal exposure route for DMF was 48.5% vs. 51.5%.

• Journal of Environmental Impact Assessment
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• v.23 no.4
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• pp.315-322
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• 2014

After the modern industrial revolution, rivers in cities became covered and disappeared due to the pressure to develop them. Likewise, their function which is to serve as the basis of natural ecology system in the cities began to be damaged. This research demonstrated that there are a total of 268 categories when it comes to the list of plants, including 64 families, 179 genera, 230 species, 36 varieties, and 1 subspecies. When the relative abundance of the plants that were found at the target research site was studied, the secondary survey demonstrated Bromus japonicus 22.97, Artemisia princeps var. orientalis 16.76 and Erigeron annuus 15.69 while third survey demonstrated Digitaria ciliaris 26.78, Ambrosia trifida 16.29 and Aster pilosus 14.31. There were 54 species of naturalized plants that appeared. Analysis demonstrated annual plant 23 classification category (43%), perennial 11 classification category (20%), multi-perennation 17 classification category (31%), woody plant 3 classification category (6%) and others. When the naturalized plants that were found at the target research site were analyzed by the place of origin, North America and EU took up 76%, which accounts for 3/4 of the all the naturalized plants. At the target research site, naturalization degree of 5 pertained to 22 classification category (41%), which was the highest, followed by 19 classification category (35%) with naturalization degree of 3, 8 classification category (15%) with naturalization degree of 2 and 5 classification category (9%) with naturalization degree of 4 in the order mentioned. Flora of Jungnangcheon did not manifest any change compared to 10 years ago. Thus, it is necessary to increase of biodiversity efforts to improve SeoulCity's natural environment and cityscape.

• Journal of Korea Water Resources Association
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• v.30 no.2
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• pp.165-175
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• 1997

This is to study the characteristics of available water resources (AWR) of the eastern coastal area in Korea. A rating curve was suggested at Yangyang water level station of the Yangyangnamdai river. Annual mean precipitation of this area is 1365.8mm. Annual mean precipitation in central and northern area of eastern coastal area is more than that of southern area because of orographic precipitation occurred by the north-easterly air flow from the East sea. By the correlation analysis of monthly rainfall depths between rainfall gauging stations it is presented that the rainfall gauging stations located in coastal region have the regional representativity, but the rainfall gauging stations located in the westward of mountains have a strong locality. AWR of eastern coastal area by the application of runoff coefficient 0.665 is 1134.5X106m3 and 28.6 percentage for total water resources. In each watershed AWR is 193.7X106m3 in the Yangyangnamdai river, 109X106m3 in the Kangnungnamdai river, and 146.0X106m3 in the Samcheokosip river. The seasonal changes of 30/3% in summer and 19.1% in water, and those of the AWR to total water resources are 86.3% in winter, 60.1% in spring, 50.1% in autumn, and 25.7% in summer. The results of this study may be used to establish the water resources planning of eastern coastal area.