• Journal of Korean Society of Forest Science
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• v.65 no.1
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• pp.1-11
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• 1984

Susceptible trees of Pinus densiflora and resistant trees of Pinus rigida following pine gall midge (Tnecodiplosis japonensis Uchida et Inouye) attack were seasonally compared to examine the variation in needle growth and photosynthetic ability, respiration rate, chlorophyll contents, carotenoid and anthocyanin contents. Also, carotenoid and anthocyanin contents of larvae both from soil and from galled tissue were compared during March and September, respectively. The plantation damaged severely by this insect consisted mostly of 10-to 15-year old P. rigida and P. densiflora. The results obtained in this study were as follows: 1) The length of the infested needles of P. densiflora decreased by 48.1 percent compared with the normal needles, while that of P. rigida did 37.4 percent. 2) All of P. densiflora and P. rigida showed higher photosynthetic ability in normal needles than in infested needles. The maximum photosynthetic ability of P. densiflora was shown in mid-August, while that of P. rigida in mid-October. In contrast to that, respiration rate of infested needles was higher than that of normal needles in both species. The respiration rate of P. rigida was higher than that of P. densiflora. 3) P. rigida had higher total chlorophyll contents than P. densiflora. The total carotenoid contents tents in infested needles were higher than those in normal needles of both species. 4) Total carotenoid contents were generally higher in P. rigida than in P. densiflora during the growing season. The total carotenoid content (0.094mg/g) in larvae from soil was similar to that (0.092mg/g) in larvae from galled tissues. 5) Infested needles of both species showed higher anthocyanin contents than normal needles. Higher anthocyanin contents in galled needles were due primarily to its active formation stimulated by larval attack. Thus, reddish-brown coloration occurred only in galled needles of P. densiflora.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.767-774
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• 2015

In recent decades, health concerns related to sodium intake have caused an increased demand for salt or sodium-reduced foods. Umami substance can enhance taste sensitivity to NaCl and may offer a unique approach to replace and reduce the sodium content in foods. In this study, hot water extraction conditions of Wando sea tangle with high umami taste were investigated. Wando sea tangle harvested in June was selected for hot water extraction based on its free amino acids composition. The quality properties of sea tangle extract were investigated at various extraction temperatures ($60^{\circ}C$, $80^{\circ}C$, and $100^{\circ}C$) and times (1 h, 2 h, and 3 h). Sea tangle extracts at the extraction temperature of $100^{\circ}C$ contained the highest soluble solids (35.47%~36.93%), and crude protein (3.75%~4.00%). Viscosities of sea tangle extracts decreased with increasing extraction temperature. Umami amino acids (glutamic acid and aspartic acid) and sensory characteristics were best at extraction conditions of $100^{\circ}C$ for 2 h. Saltiness enhancement of sea tangle extract powder was determined. Saltiness intensities of NaCl solution after adding 1% sea tangle extract powder were enhanced (1.84~4.25-fold). At the same saltiness intensity, sodium contents of NaCl solution with 1% sea tangle extract powder were 12.24~24.33% lower than that of NaCl solution. These results suggest that it is possible to reduce sodium in foods with sea tangle extract as a natural salt enhancer without lowering overall taste intensity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.47-68
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• 1970

Experiments were conducted by moderate season culture of each of 7 early, medium and late maturing varieties which were considered to be of strong salt tolerance in non-salty, low- and high-salty reclaimed areas (salt content: 0.5% and 1% at the end of April). The results of the experiments revealed that the early maturing varieties were suffered greatly from salt damage in such reclaimed salty area which is the "fall better type" in the year-round changes of soil salt concentration in Korea. Better yielding varieties in the salty area showed generally a high yield ratio in the salty area compared with the non-salty area. This indicates that they are strong salt tolerant varieties. It seemed that the salt tolerance could be measured by the number of delaying days in heading, the growth rate of culm length, number of panicles and number of grains per panicle in the salty area to compare with the non-salty area. The effects or salt damage on the yields of each variety at maturing stage and agronomic characteristics in the salty area were compared and discussed with the non-salty area.alty area.

• Economic and Environmental Geology
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• v.41 no.6
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• pp.695-708
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• 2008

In order to evaluate the geochemical behaviors of elements with waste rocks in the abandoned Jangpoong Cu mine area, total concentration analysis and leaching experiments were performed. The content of elements within waste rocks compared with background values decreased in order of As>>Cu>Pb>Cd>Co. Leaching experiments were carried out at various extraction environments, considering the acid rain ($0.00001{\sim}0.001N\;HNO_3$) and the acid mine drainage ($0.001{\sim}0.1N$ HNO3). After 24 hours of reaction with different acidic solution, the leaching characteristics of waste rocks were classified into three types according to final pH of leaching solution. Type I refers to the case that the final pH of leaching solution was lower than that of the reaction solution due to the dissolution of acidic minerals from rocks, while type 2 and 3 refer to the case that the final pH maintained higher than that of the reaction solution. Theses types include in acid buffering minerals such as clay minerals and carbonate minerals. The leaching characteristics of the elements after the reaction could be categorized into As-Co-Fe, Cu-Mn-Cd-Zn, and Pb. As-Co-Fe started to get leached under 2.5 of pH regardless of changes in the final pH, and Cu-Mn-Cd-Zn showed different initial leaching pH according to the types of final pH changes. Based on the pH value where leaching started regardless of leaching concentration, the relative mobility of each element was in the order of Mn Zn>Cd>Cu>>Fe Co>As>Pb. Thus, more higher mobility elements(Zn, Mn and Cu) were leached by reacting with acid rain water. Acid mine drainage may result in distributions of elements having relatively less mobility(As, Fe, Co and Pb).

• Journal of Biosystems Engineering
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• v.11 no.2
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• pp.31-40
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• 1986

Cylindrical and conical types of grain-straw separation equipment which has a stationary crimped sieve drum with rotating inner rotor were constructed. The developed equipments were tested to investigate the characteristics of separating performance under various mechanical conditions and crop conditions. As increase of the inclination of equipment and decrease of pitch of cover vane, the grain recovery was increased while straw rejection was decreased. The grain recovery and overall efficiency were decreased as the rotor speed and feeding velocity were increased for both varieties of rice, moisture contents, and test equipments. Conical prototype equipment performed higher straw rejection, lower grain recovery, and lower power requirement. However, separation performance of conical type equipment was more widely varied with various test conditions compared to cylindrical one. The performance of both equipments showed relatively insensitive to crop feedrate and crop properties, such as variety, moisture content, and grain-to-straw ratio.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.56-64
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• 2001

Composting of livestock feces is economic and safe process to decrease the possibility of direct leakage of organic pollutants to ecosystem from commercial and environmental point of view. This study was conducted with three different experiments related to composting of livestock feces. The purpose of experiment 1 was to investigate changes of characteristic of compost pile during composting period by low temperature in cold season. To compare composting effect of experimental compost pile and control pile exposed in cold air, experimental compost piles were warmed up by hot air until their temperatures were reached at $35^{\circ}C$. Sawdust, Ricehull and Ricestraw were mixed with livestock feces as bulking agent. The highest temperatures of compost pile during composting period were in sawdust, rice hull, rice straw, and control were $75^{\circ}C$, $76^{\circ}C$, $68^{\circ}C$, $45^{\circ}C$ respectively. Moisture content, pH, C/N and volume of compost were decreased during composting period. Experiment 2 was carried out to study utilization effect of compost by plant. A corn was cultivated for 3 years on fertilized land with compost and chemical fertilizer. The amount of harvest and nutrition value of corn were analyzed. In first year of trial, the amount of harvest of corn on land treated with compost was lower by 20% than that of land treated with chemical fertilizer. In second year, there was no difference in yield of com between compost and chemical fertilizer. In third year, the yield of com on land fertilized with compost was much more than that of land fertilized with chemical fertilizer. The purpose of experiment 3 was to estimate the decrease of malodorous gas originating from livestock feces by bio-filter. Four types of bio-filters filled with saw dust, night soil, fermented compost and leaf mold were manufactured and tested. Each bio-filter achieved 87-95% $NH_3$ removal efficiency. This performance was maintained for 10 days. The highest $NH_3$ removal efficiency was achieved by leaf mold on the first day of operation period. It reduced the concentration of $NH_3$ by about 95%. Night soil and fermented compost showed nearly equal performance of 93 to 94% for 10 days from the beginning of operation. The concentration of hydrogen sulfide and methyl mercaptan originating for compost were equal to or less than $3mg/{\ell}$ and $2mg/{\ell}$, respectively. After passing throughout the bio-filter, hydrogen sulfide and methyl mercaptan were not detected.

• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.157-181
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• 2020

Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.

• Journal of Science Education
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• v.38 no.3
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• pp.670-690
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• 2014

The purpose of this study was to analyze paper and pencil test items of life science I in high school to diagnose problems of the test items developed by teachers, and to provide some implication for better assessment. 690 selection-type items and 162 supply-type items in life science I were collected from 10 general high schools. In the analysis of test items, the ratio of the selection-type item and the supply-type item was 81:19 in the number of items based on item type, while the ratio was 74.4:25.6 in the distribution of marks, indicating that the distribution of marks compared to the number of items was higher in the supply-type items. In the analysis by the Bloom's revised taxonomy of educational objectives, the items of 'conceptual knowledge' in the knowledge and those of 'understanding' in the cognition process were shown most in both the selection-type item and the supply-type item. In the analysis by the science assessment frameworks of NAEA, the items of 'knowledge' were shown 9 times more than those of 'inquiry'. When compared to the level of difficulty presented in the two-way specification table and the percentage of correct answers in the selection-type item, the concurrence was 41.5%. When compared to the ratio of number of items based on the item type of the supply-type items, the short-answer items were 34.0%, the descriptive items were 61.1%, and the drawing items were 4.9%. The drawing items were mainly developed in the unit of 'Cells and Continuity of Life'. When the descriptive items were classified by the acceptance of response, all the items were 'response restricted' type, and the items of 'restricted in content range' type among them were highest. When the items were classified by presentation of data, the items of 'presentation of data' type were highest(65.4%), and when classified by type of question, the items of 'knowledge description' type were highest(80.4%). In conclusion, it is needed to develop items belonging to 'inquiry' area more in the school, and to increase the ratio of the descriptive items, presenting various types of items.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.234-248
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• 1998

Seven box cores from the disposal areas located in the southern part of the East Sea (Stations Band B') and in the offshore to the east of Pusan (Stations J and J'), and from their surrounding areas (Stations J2, J6 and H) were collected to investigate the effect of dumped wastes on the foraminiferal assemblages. The species diversity indices [S, H(S), E] of foraminifera and the total number of foraminifera show significant differences between the ocean waste disposal areas and their adjacent areas. Ocean waste disposal areas located in southern part of the East Sea (Stations Band B') show not only smaller number of foraminifera species but also lower values of coarse fraction content in the sediment and the number of benthic and planktonic foraminifera than the surrounding areas. Another ocean disposal area located offshore Pusan (Station J') contains abnormally greater number of planktonic (approximately 300 000 individuals/lO g dried sediment) and benthic (approximately 300, 000 individuals/10 g dried sediment) foraminifera compared to those of the adjacent areas. The waste dumped at Station J' probably acts as a nutrient causing the greater number of foraminifera. Station J shows low species diversity indices [S, H(S)]. The number of benthic foraminifera decreases from the surface to the downcore at Station J, which indicates that Station J is under stress. However, Stations J', J2 and J6 are under stable conditions as evidenced by the greater species diversity indices [S, H(S)] compared to other stations. No foraminifera were found with biological disease or abnormal chambers, which commonly occur in extremely stressed environment, in both the ocean disposal and adjacent areas. The organic matter decay of the wastes dumped in the study areas has not made the bottom water corrosive.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.145-158
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• 1994

This study was performed to investigate the knowledge and attitude of workers in small scale industries on health management, and to provide the basic data for more effective service by the group occupational health service system. The knowledge and attitude of 247 workers and 46 health personnel in the industries scattered around Incheon were investigated from December 1992 to February 1993. The results were summerized as follows ; 1. There were significant differences between the workers and the health personnel by age, sex, marriage status, job-position and education level. 2. The recognition level of the workers to contract work related disease was significantly higher than that of health personnel, and recognition level of the workers on environmental hazards and on the utility of measuring hazards were lower than that of health personnel. 3. The recognition level on the content of the group occupational health service system was significantly different between workers and health personnel, 72.6% of the responses from the workers answered that they did not know what the group occupational healthe service system was, but 82.2% of the responses from the health personnel answered that they knew well what it was. And 79.0% of all respondents thought it was necessary for worker's health. 4. Seventy three percent of the respondents from the workers indicated that they had never taken health education. However, 93.0% of all respondents answered positively for the need of health education to promote their health. 5. Current health service system was judged to be insufficient for the demand of workers for better health. Most of the respondents prefered a formal but flexible health service system and they wanted the periodic health examination to be followed up. It was revealed that despite of poor knowledge, the demand of workers for health service was higher than the current supply. Therefore, this study suggests that educating both health personnel and workers to obtain correct knowledge on the hazards to work enviroment and health management is needed for effective occupational health service.