• Horticultural Science & Technology
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• v.30 no.1
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• pp.85-89
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• 2012

To investigate the bird's dieting behavior for several fruits in orchards, this study was carried out in 2008. Black-billed magpies (Pica pica), azure-winged magpies (Cyanopica cyanus), and brown-eared bulbuls (Hypsipetes amaurotis) made their unique marks on the surface of pear and apple fruits; black-billed magpies pecked fruits strongly and left round holes with perpendicular angle, whereas those of azure-winged magpies and brown-eared bulbuls were sack-shaped with narrow neck and marked unique stripes on the skin. For the fruits of pear and apple from bagging practices, the birds showed different foraging behavior; black-billed magpies could injure all kinds of fruits whether with paper bags or not, but azure-winged magpies and brown-eared bulbuls could not attack the fruits with paper bag. Azure-winged magpies and brown-eared bulbuls preferred pear fruits to those of apples and satsuma mandarins in the cage trials. To reduce the injuries by azure-winged magpies and brown-eared bulbuls on pear and apple fruit, wrapping bag should not be impaired. Introducing azure-winged magpies to Cheju should be prohibited for the potential citrus injury by them.

• Development and Reproduction
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• v.12 no.3
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• pp.207-213
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• 2008

In order to monitor the developmental features of embryos, larvae, and juveniles of chub mackerel, Scomber japonicus, the fertilized eggs were obtained by artificial insemination. The fertilized eggs were spherical in shape and floated separately. Their membrane and yolk having 1 oil globule were transparent. The transparent eggs, having one oil drop in the yolk, were $0.94{\sim}1.02\;mm$ (mean, $0.95{\pm}0.03\;mm$) in diameter. The fertilized eggs started hatching at 51 hrs after fertilization in $20{\pm}0.5^{\circ}C$ water. The total length of the hatched larvae was $2.52{\sim}3.0\;mm$ (mean, $2.75{\pm}0.04\;mm$). At hatching, the larva, with the mouth and anus not opened yet, had yolk sack, $28{\sim}31$ myomeres and eyes with melanophore. Yolk completely 2 days after hatching and the total length of post-larvae $3.12{\sim}3.63\;mm$ (mean, $3.39{\pm}0.05\;mm$). At the 18 days after hatching, the tip of tail became curved at the end and the stems for pectoral, dorsal, and caudal fins appeared. Juveniles, having all firm rays, was $44.12{\sim}58.72\;mm$ (mean $55.95{\pm}6.74\;mm$) in TL 25 days after hatching.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.72-85
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• 2003

The purpose of this study is to establish the basis of the ecological restoration on the limestone mines in Korea, through the research of the revegetation measures of the disturbed slopes in Japanese limestone mines and the analysis of the case of Ibuki and Bukou limestone mines to realize the restoration works successfully. According to the number of mines to carry out the revegetation works increase every year, the revegetation area and amount of planting also go on increasing in Japan. In the small mines the environmental problem is not recognized seriously, but some mines have muchly invested in the revegetation of the damaged land by mines. Ibuki mine in Shiga-gen is practicing the four principles for the restoring of the revegetation in the disturbed slopes by mines. Firstly, the mean slope preserves $37^{\circ}$ in the last rock cut slopes. Secondly, the last rock cut slopes to rehabilitate are covered with the soil dressing 30cm high. Thirdly, the grasses in the mining area are digged up beforehand, and then they are reused to the revegetation works of rock cut slopes. Lastly, from the upper rock cut slopes the revegetation works begin, the process of the above are repeated, as the result, the restoring works will be completed. Upon the ground of these principles, the complex of the original vegetation and the native species seeding, that is, the revegetation technique of Ibuki have established. In the difficult area to revegetate, sodding works, heaping up vegetation-sack, seed-spraying, heaping up soil-sacks and planting works are adapted variously. Bukou mine in Saitama-gen try to maintain the revegetation, the screening and the stability of the enormous mining rock cut slope, and for these works, the activity of 'Chichibu Working Group of Rock Wall for Limestone Mines' contributes largely. The chief technique of the revegetation in Bukou mine is following; after the making the berm on the rock cut slopes, the soil dressing is filled in it, and the trees is planted for the screening of the rock cut slopes. They devide the rock cut slopes into four typical types, and choose the different ways to make the berm and fill the soil dressing in characteristic. Most of the planting trees are consist ofthe native species of Mt. Bukou through the stages of the nursery and transplantation. Not only the revegetation of the demaged land but also the breeding of the conservational plants also are their important business.

• Korean Journal of Plant Tissue Culture
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• v.24 no.2
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• pp.77-81
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• 1997

For the early selection of heat-tolerant clones, the true potato seeds of 750 clones were obtained by several cross combinations : $CIP\;575015\;{\times}\;katahdin,\;CIP\;575015\;{\times}\;B6603-6,\;84\;I\;35-4\;{\times}\;katahdin,\;CIP\;575015\;{\times}\;NookSack,\;and\;CIP575015\;{\times}\;Superior.$ The ratios of in vitro tuberization at 3$0^{\circ}C$ were decreased by 43% in all cross combinations compared with at 2$0^{\circ}C$. In particular, tuberization rate of $CIP575015\;{\times}\;katahdin$ cross at 3$0^{\circ}C$ was only 21%. On the other hand, the rate of tuberization of $CIP575015\;{\times}B6603-6$ cross was 58 % at 3$0^{\circ}C$, so this cross combination was thought to be good heat-tolerant clone. To screen the heat-tolerant clones in lower land during high temperature period, microtubers were cultivated in Kangnung, and the characters of tubers and productivity were examined. Among screened clones, one clone at 2$0^{\circ}C$ and three clones at 3$0^{\circ}C$ were shown to be heat-tolerant. The yield of 89ML75-8 was 88% more than that of Superior, and dry weight rate of 89 ML64-11 was 18.8%. Therefore, 89ML64-11 clone was considered as a good cultivar for processing.

• Resources Recycling
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• v.18 no.5
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• pp.63-71
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• 2009

Recyclable wastes coming into material recovery facilities(MRFs) is mostly packed by plastic bag or sack bag. Bag rupturing device is essential to improve capacity and efficiency of MRFs. Bag opening works of MRFs is mostly done by numerous workers and shredder-type bag rupturing device. It often makes a problems; decreased capacity, shredded recyclables, worker safety by explosion and broken glasses, etc. In the present work, bag rupturing device with octagonal rotating blade drums has been developed to solve the existing problems and environment assessment is also performed during operation of the device. Capacity of the device was about 5.6 ton/hr at 8.2 rpm of drum revolution speed and 1.25 m/min of belt conveyor speed. It satisfied initial designed capacity(5.0 ton/hr) and max. capacity 8.8 ton/hr was achieved at 12.5 rpm of drum revolution speed and 1.50m/min of belt conveyor speed. Bag rupturing efficiencies on outer and inner bag were obtained at 100% and about 95.6% as average, respectively and original form of glass bottles in the bag was maintained without broken by about 96.5%. This result shows that the safety in hand sorting by the workers could be improved. As result of environmental assessment on the noise, vibration and particulates, the measured levels on noise, vibration and particulates show the below standard regulatory limits. It could be concluded that the problems of existing devices in MRFs could be solved by adopting the bag rupturing device with octagonal rotating blade drums in on-site operation.

• The Korean Journal of Malacology
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• v.31 no.3
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• pp.171-178
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• 2015

The reproductive ecology of freshwater bivalve, Unio douglasiae in Lake Uiam were examined from March 2014 to February 2015. The gonads distributed in reticular connective tissue, the dioecious clams take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The gonad index (GI) began to increase in April, reached the maximum value in July and to decrease in August. The reproductive cycle of U. douglasiae can be divided into five successive stages: multiplicative stage (November to January), growing stage (February to March), mature stage (February to May), spawning stage (April to September), recovery stage (August to December). The spawning periods were from April to September, and the main spawning occurred between April and July. The shell length at 50% group maturity was estimated to be 29.4 mm.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.51-61
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• 1969

In order to eliminate the considerable loss of rice by insects, to protect the human body from toxin excreted by some microbes, and to promote the storage efficiency of rice by employing the irradiation, the following experiments were carried out. Two varieties of rice, Paldal and Nongkwang polished and unpolished by the conventional methods and were packaged in polyethylene bags. After irradiating to the doses of 6-400 Krad of gamma-radiation from a $Co-^{60}$ source the samples were stored at the room temperature $20^{\circ}C$ for 8 months. The effects of radiation in terms of the removal of insects and microbes and the changes of chemical components (such as moisture, amylose, free sugar, and rancidity) were determined monthly from march to October during the storage. 1) Infestation of insects was greatly influeneed by the packaging materials used. There was no infestation in rice being packaged in a polyethylene bag, while as the rice packaged in a straw sack was infested in two months of the storage. 2) Some yeast and molds survived 400 K rad of radiation. Sterilizing dose to inhibit reproduction and growth of microbes was presumed to be higher than 400 K rad. Yeast mainly were found on the surface of rice, but mold were embeded into rice kernels by mycelium. 3) Changes of moisture contents during storage was not affected by radiation but was by humidity of the storage room. 4) Amylose content in starch increased with increasing dose of radiation and with the length of storage time, indicating possible depolymerization of starch molecules. 5) Free reducing sugar content was not affected by radiation and decreased with storage time. 6) Rancidity also increased with does and storage time.

• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.255-258
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• 1986

This study was carried out to determine the shelf-life and quality changes of perilla leaves (Perilla ocimoides L.) in relation to changes in the concentration of biochemical components during storage. The shelf-life of perilla leaves was 2 to 3 days at room temperature and 6 days at $3^{\circ}C$. This was extended to 12 days at room temperature and 20 days at $3^{\circ}C$ by packaging in a 0.01 mm thick polyethylene film sack (PEFS). The ascorbic acid concentration of fresh perilla leaves was 23 mg per 100 g fresh weight. This declined to 16 mg per 100 g fresh weight on the 4th day of storage in all treatments. Ascorbic acid concentrations decreased further to 7 mg on the 8th day at room temperature and 8 mg per 100 g on the 16th day at $3^{\circ}C$ in PEFS. Total and reducing sugar concentrations in the controls were higher than those in the PEFS storage at room temperature. Protein and free amino acid concentrations gradually increased during storage. A higher protein level was maintained in the control than in the PEFS treatment. Changes in nucleic acid concentration and peroxidase and polyphenoloxidase activities during storage were also measured in relation to the changes in quality of perilla leaves.

• Food Science and Preservation
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• v.8 no.4
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• pp.351-355
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• 2001

This study was carried out to examine the of quality on the dried Omija according to its package materials and storage plates. The changes of moisture contents, anthocyanin content, molds damage rates, and color values were measured during storage. In the sealing up by the P.E file, the moisture contents of the dried Omija had just a little differences among the storage places, but in the gauze bag remarkably as the storage period goes on, especially in this case, 8 months later since the storage in the cool chamber, the damage rates of the dried Omija by the mold was 9.0%, twice as much as in the indoor bag packaging it was increasand after 10 months, that was lather high in the indoor and warehouse. The anthocyanin content of the dried Omija after the storage of 10 months was the highest at 0.05mm black P.E film package in the cool chamber, which was 55.7 mg/100g, but in the indoor and warehouse 39.7, 45.0mg/100g, respectively. These results show thats the storage conditions had an important effect on the quality of the dried Omija during the long-term storage.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.276-285
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• 2001

This report surveyed degradation of forest environment and rehabilitation in Ashio of Japan. Since 1880, a large scale forestry in this area has been destroyed by sooty smoke, and the local government invested heavily to rehabilitate the damaged forestry and denuded mountains. These degradations are due to complex operations, such as sulfurous acid gas from copper refinery, forest fires, steep slope and disadvantageous climate. The rehabilitation works on degraded forestry(2,399ha) were undertaken by tree planting fur three years from 1897. However, forest degradation and disasters were continued, and the total damaged areas were about 2,400~3,000ha in 1956. A Manual labor method, a Helicopter method and also Combination of manual labor and helicopter method had been adopted to rehabilitation works from 1945 to 1996, while 828.19ha of the degraded mountains was rehabilitated. Total investment for those projects was 80 billion yen. A debris control dam, a soil arresting structure, a vegetation-block, a vegetation sack measures and tree planting have implemented significantly fur the method of rehabilitation. An objective of manual labor works is a complete rehabilitation on each place through 3 stage working. The revived green areas accounted fur 49% of the total, and the entire afforest areas are less than 10%. In coming 25 years, an amount of 21.3 billion yen will be invested to rehabilitate 564ha of degraded mountain lands. However, it is impossible to estimate that how long it will take until the whole degraded mountain lands are completely rehabilitated. Rehabilitation works in Ashio may be applicable to environmental restoration and revegetation in the abandoned coal-mine lands of Korea.