• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.19-29
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• 1994

A large volume of paper mill sludge(PMS) is produced every day from paper industries after treatments of waste water and it costs too much to dispose of the sludge. Since PMS consists mostly of biodegradable organic matter, cellulose, it is desirable to recycle it by proper treatments such as composting. In this study, experiments were conducted using a small scale reactor(12l) to establish optimum conditions for efficient composting of PMS of which initial pH, C/N ratio, and moisture content were 7.1, 28~30, and 60~65%, respectively. No heavy metals such as mercury, cadmimum, and lead were not detected in the PMS. Various levels of forced aeration, 1 minute aeration per every 30, 60, 120, 240, and 480 minutes were applied and 1 minute aeration per 60 and 120 minutes found to be proper for composting of 8l PMS in this system. Relationship between $CO_2$ production and temperatures was positively correlated with r> 0.82 suggesting that the normal decomposition of PMS by microorganisms occurred. However, under the condition of aeration interval over than 240 minutes, a negative relationship between two parameters was found indicating the occurrence of abnormal(maybe anaerobic) degradation. The amount of added nitrogen also affected composting of PMS resulting in the increase of $CO_2$ production and temperature. Semi-field tests using 100kg PMS in a static pile sysem showed that PMS could be composted efficiently under optimal environmental conditions. The parameters determining efficiency of composting such as C/N ratio, aeration, moisture content, and pH need to be monitored.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.172-182
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• 2006

This study was designed to assess molinate fate in the lysimeter by measuring the total radioactivity in the leachate, evolved $^{14}CO_2$, and $^{14}C$-residues in soil and rice plant. The amounts of applied $^{14}C$ in the leachate from the lysimeter for 20 weeks were 1.05% in 2.31 pore volume (217,465 mL) at the first and 0.34% in the second year, respectively. The amount of $^{14}CO_2$ evolved from the lysimeter accounted for 6.47% and 0.03% of applied $^{14}C$ in the first and second year. The $^{14}C$-activities in the soil layer of the lysimeter were distributed 18.0% (1st) and 13.3%(2nd) in the depth of 0 to 10 cm, 4.3 (1st) and 1.1% (2nd) in the depth of 10 to 20 cm. Most of the applied $^{14}C$ was detected in the top 20 cm soil layer. Total $^{14}C$ in rice plants grown at lysimeter were detected 11.46% of applied $^{14}C$. 11.11% in straw, 0.24% in brown rice grain, 0.08% in chaff and 0.03% in ears were distributed in the first year. Consequently, environmental fate of molinate using lysimeter simulating a paddy rice field were investigated 25.24% in soil, 11.64% in rice plant, 1.05% in leachate, 6.74% in evolved $^{14}CO_2$ and 0.02% in volatilized organic chemicals in the first year.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.95-120
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• 1996

College level educational training system for the allied health manpower in the country is one of the oldest junior college education programs, and has been developed at very steady phase. Since the school years of the programs limited for 2 to 3 years by the education related law, qualification of the manpower is insufficient to meet the rapidly changing needs in the field of allied health and medicine. The system is comparable with that of developed countries where 4-year baccalaureate degree programs are basically required to be an allied health personnel. Thus, education and training background of allied health program graduates of the country confronts the barriers in competition and cooperation with the graduates of foreign countries at equal basis. Beside, junior college graduates can hardly find the way through advanced courses at 4-year colleges in their specialties except a few programs such as environmental sicience or courses in hygiene. It has long been sought to develop the education and training programs for junior college graduates. Some of them are already materilized and some show remarkable progress while some need to tackle. Wide opening of the opportunity to enroll extensive education program for the junior college graduates of allied health science majors in 4-year colleges with eventual grant of bachelor's degree for those who successfully completed the programs should soon be substantiated. The study was focused to emphasize the necessity of the extensive education and training for the junior college graduate allied health manpower, and to show possibility of the education program development in connection with the 4-year degree granting education programs. The outcome of the study can be summarized as followings. 1. A total number of graduates from eight allied health sciences related programs of junior colleges by the year of 1995 are 109,320. 2. According to the survey report analysed through questionnaires, 99.7% of respondents including administrative deans and professors of junior colleges agreed with the establishment of extensive education and training programs in junior colleges. 53.9% of administrative deans, 52.9% of professors and 47.6% of the graduates expected that it is possible to learn more about their majors, and to earn bachelor's degree through the extensive education programs. Other opinions include that the programs can provide supplementary opportunities to fortify in the area of basic life science, and development of research and technology. 3. It was also found through the survey that 91.2% of the deans, 87.8% of the professors and 68.2% of the graduates responded that the most appropriate organizations to open the extensive education and training programs for allied health manpower are junior colleges where allied health personnel are taught and trained. The majority of the respondents agreed that the acceptable number of credits offered for the previous 2-year junior college graduates are $50\sim60$, and those for the current 3-year graduates are $20\sim30$ units. 4. It was strongly suggested through the survey that baccalaureate degree should be granted for those who successfully completed the extensive courses. The suggestion was claimed by 94.1% of the deans, 89.4% of the professors and 83.4% of the graduates. 5. The model curricula for the extensive education and training programs for the allied health manpower are designed for the purpose of broad capability in practice, enrichment of knowledge and promotion of proficiency for the self access in the major areas. 6. To meet the universal standards of allied health education and training program, it is recommended that opening of the curricula for the extensive, and as well as intensive, courses within junior colleges(continuation education institute) should be materialized. The special baccalaureate degree programs within junior colleges are also recommended to accommodate the junior college graduates and to grant the degree fellowing successful completion of the courses. As a part of the education revolution in progress, the school years at junior college level should be flexible depending upon the nature of course and trend of the universe. For instance, the school years for the allied health manpower should be extended to two to four years from current two to three years.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.62-69
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• 2003

The aim of research is the evaluation of the $Cr^{6+}$ emission features of the liquid injection through emission experiments in varying conditions, based on a field-mixing ratio. The results showed that the content of $Cr^{6+}$ content in cement measured had an Ordinary Potland Cement (OPC) of 25.3 mg/kg, which constitute the largest portion among the other materials. Likewise, the emission experiment of homo-gel and sand-gel generally satisfied the standard of KSLT (Korea Standard Leaching Test) in waste of 1.5 mg/L, but in case of the standard of KSLT in soil the emission of OPC $Cr^{6+}$ of 4.85 mg/kg. These conditions is a little exceeded the criteria in the ‘Ga’ area in terms of Korea Soil Environmental Preservation Law. In addition, results generated by the mock-up injection facilities revealed that $Cr^{6+}$ emission increased as Water/Cement and injection pressure increased. At injection pressure higher than 4 kg/㎤, $Cr^{6+}$ emission exceeded the water preservation standard of 0.5 mg/L. Similarly, a pattern experiment of C $r^{6+}$ emission according to pH was conducted, in order to evaluate the $Cr^{6+}$ emission features of grout materials in leachate below pH 5 such as pH 4 acid rain or landfill. Results show that $Cr^{6+}$ emission dramatically increased in high acidic or basic state. It indicates that $Cr^{6+}$ emission will probably increase in an environment where grout materials are injected. On the other hand, concentration of leachate was determined in areas where grout materials are used. The results show that the concentration of emission in an ultra purity condition does not manifest intensity, and is affected in the OPC>MC>SC order. It means that the pollutants or $Cr^{6+}$ emission increases with decreasing concentration. As such, $Cr^{6+}$ emission will probably exceed the countermeasure criteria according to the types of gout materials. Similarly, high pressure or injection will cause increased $Cr^{6+}$ emission. Therefore, the selection of materials or mixing ratio should be considered in general as well as according to specific industries, based on the strength and pH of $Cr^{6+}$ emission.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.33-39
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• 1999

In order to understand the importance of tidal action and $NH_4{^+}$ -nitrification in the removal of dissolved oxygen (DO) and $NH_4{^+}$, concentrations of DO, $NH_4{^+}$, $NO_2{^-}$ and $NO_3{^-}$ were measured with time for water samples collected at different tidal state in the eutrophic macrotidal Han River estuary. Field measurements indicated that most environmental parameters, except for the water temperature and DO concentration, were tightly controlled by the eutrophic freshwater runoff and large-scale tidal action. Dark incubation of the water sample at $25^{\circ}C$ showed that the removal rates of DO and $NH_4{^+}$ in high tide sample were 2.76 ${\mu}M\;O_2\;d^{-1}$ and 1.76 ${\mu}M\;N\;d^{-1}$ respectively, and increased to 5.66 ${\mu}M\;O_2\;d^{-1}$ and 3.36 ${\mu}M\;N\;d^{-1}$ respectively, in low tide sample. These changes indicated that microbial degradation and uptake of organic matter and inorganic nutrients were more active during low tide. $NH_4{^+}$-nitrification responsible for total DO removal in low tide (23.81%) and $NH_4{^+}$ turnover rates due to $NH_4{^+}$-nitrification in low tide (0.18 $d^{-1}$) were approximately 3.7 times and 3 times, respectively, higher than those in high tide. These results indicated that $NH_4{^+}$ -nitrifying bacteria introduced into the Han River estuary during low tide played a significant role in the removal of DO and $NH_4{^+}$. The decreasing removal rates in DO and $NH_4{^+}$ with the increasing tidal level seemed to be associated with the salinity impact on the halophobic freshwater $NH_4{^+}$-nitrifying bacteria. The results implied that anthropogenic $NH_4{^+}$ sources should be treated prior to the freshwater runoff into the estuary for the effective control of $NH_4{^+}$ in the Han River estuary. These results also suggest that parallel ecological studies on the chemoautotrophic nitrifying bacteria are essential for the elucidation of nitrogen cycles in the eutrophic Han River estuary.

• Journal of the Mineralogical Society of Korea
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• v.26 no.3
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• pp.161-174
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• 2013

The geology of the weondong deposit area consists mainly of Cambro-Ordovician and Carboniferous-Triassic formations, and intruded quartz porphyry and dyke. The skarn mineralized zone in the weondong deposit is the most prospective region for the useful W-mineral deposits. To determine the skarn-mineralization age, U-Pb SHRIMP and K-Ar age dating methods were employed. The U-Pb zircon ages of quartz porphyry intrusion (WD-A) and feldspar porphyry dyke (WD-B) are 79.37 Ma and 50.64 Ma. The K-Ar ages of coarse-grained crystalline phlogopite (WD-1), massive phlogopite (WDR-1), phlogopite coexisted with skarn minerals (WD-M), and vein type illite (WD-2) were determined as $49.1{\pm}1.1$ Ma, $49.2{\pm}1.2$ Ma, $49.9{\pm}3.6$ Ma, and $48.3{\pm}1.1$ Ma, respectively. And the ages of the high uranium zircon of hydrothermally altered quartz porphyry (WD-C) range from 59.7 to 38.7 Ma, which dependson zircon's textures affected by hydrothermal fluids. It is regarded as the effect of some hydrothermal events, which may precipitate and overgrow the high-U zircons, and happen the zircon's metamictization and dissolution-reprecipitation reactions. Based on the K-Ar age datings for the skarn minerals and field evidences, we suggest that the timing of W-skarn mineralization in weondong deposit may be about 50 Ma. However, for the accurate timing of skarn mineralization in this area, the additional researches about the sequence of superposition at the skarn minerals and geological relationship between skarn deposits and dyke should be needed in the future.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.286-297
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• 2016

Clostridium perfringens is both a ubiquitous environmental bacterium and a major cause of human gastrointestinal disease, and C. perfringens food poisoning ranks among the most common gastrointestinal diseases in developed countries. 120 isolates of C. perfringens were obtained from food-poisoning outbreaks in 2013~2014, Gyeonggi-do. Using PCR, all 120 isolates were identified as C. perfringens type A. Of the tested isolates, 49 isolates carried the cpe gene, 71 isolates carried the cpb2 gene. The outbreak cases of cpb2 and cpe /cpb2 genes were 7 and 7, whereas the outbreak cases of cpe-gene were 2. The epidemiological relationship between C. perfringens isolates has previously been investigated chiefly by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). The genetics relatedness of the isolates raged from 53.5-100% and 75 district PFGE type were observed. The PFGE results revealed a wide genetic diversity among the 64 cpb2 carrying isolates (except 7 isolates), while 46 cpe-carrying isolates (except 3 isolates) showed a high genetic similarity. The MLST analysis revealed that 14 cpe isolates (cpe-chromosomal isolates) belong to a distinct cluster that is significantly distant from all the other cpb2 isolates (cpe-plasmid carrying and cpe-negative isolates). The isolates carrying a cpb2 appear to be rarely related, and are more variable than chromosomal cpe isolates. The results suggest that the cpe-positive outbreak isolates showed close genetic relation, whereas the cpb2-positive isolates revealed a wide genetic diversity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.107-117
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• 2004

If doubtlessly contributes much to agriculture and rural development. The roles can be summarized as; 1. to activate rural areas and to provide more comfortable and safe rural life with equivalent services to those in urban areas, facilitating distance education, tole-medicine, remote public services, remote entertainment etc. 2. To initiate new agricultural and rural business such as e-commerce, real estate business for satellite officies, rural tourism and virtual corporation of small-scale farms. 3. To support policy-making and evaluation on optimal farm production, disaster management, effective agro-environmental resource management etc., providing tools such as GIS. 4. To improve farm management and farming technologies by efficient farm management, risk management, effective information or knowledge transfer etc., realizing competitive and sustainable farming with safe products. 5. To provide systems and tools to secure food traceability and reliability that has been an emerging issue concerning farm products since serious contamination such as BSE and chicken flu was detected. 6. To take an important and key role for industrialization of farming or lam business enterprise, combining the above roles.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.74-87
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• 2016

Potato phenology, growth, and yield are projected to be highly affected by global warming in the future. The objective of this study was to examine the responses of potato growth and yield to environmental elements like temperature, solar radiation, and daylength. Planting date experiments under open field condition were conducted using three cultivars differing in maturity group (Irish Cobbler and Superior as early; Atlantic as mid-late maturing) at eight different planting dates. In addition, elevated temperature experiment was conducted in four plastic houses controlled to target temperatures of ambient temperature (AT), $AT+1.5^{\circ}C$, $AT+3^{\circ}C$, and $AT+5^{\circ}C$ using cv. Superior. Tuber initiation onset was found to be hastened curve-linearly with increasing temperature, showing optimum temperature around $22-24^{\circ}C$, while delayed by longer photoperiod and lower solar radiation in Superior and Atlantic. In the planting date experiments where the average temperature is near optimal and solar radiation, rainfall, pest, and disease are not limiting factor for tuber yield, the most important determinant was growth duration, which is limited by the beginning of rainy season in summer and frost in the late fall. Yield tended to increase along with delayed tuber initiation. Within the optimum temperature range ($17^{\circ}-22^{\circ}C$), larger diurnal range of temperature increased the tuber yield. In an elevated temperature treatment of $AT+5.0^{\circ}C$, plants failed to form tubers as affected by high temperature, low irradiance, and long daylength. Tuber number at early growth stage was reduced by higher temperature, resulting in the decrease of assimilates allocated to tuber and the reduction of average tuber weight. Stem growth was enhanced by elevated temperature at the expense of tuber growth. Consequently, tuber yield decreased with elevated temperature above ambient and drop to almost nil at $AT+5.0^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.264-272
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• 2011

It needs to develop high phosphate-available rice that is able to minimize environmental pollution caused by phosphate fertilizer. Then we have transformed 4 rice transporter genes, OsPT(Oryza sativa Phosphate Transporter)1, OsPT4, OsPT7 or OsPT8, to rice (Oryza sativa cv. Dongjin) via Agrobacterium-mediated transformation. We tested adaptation in the P-deficient condition of Dongjin (parental) and each transgenic line in the pot and the field conditions. Definite physiological changes have been observed in OsPTs transgenic lines including culm length, root formation and heading date. Phosphate uptake at harvesting stage was about three times higher in OsPT1-OX (overexpression) and OsPT4-OX than in Dongjin (wt) without P application. There are no variations in total phosphate-content of brown rice of OsPT1-OX in spite of high phosphate uptake. Practically the expression of OsPT1 has contributed to stabilize grain production without P fertilization in rice cultivation than Dongjin.