• Korean journal of applied entomology
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• v.51 no.1
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• pp.67-72
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• 2012

This study was conducted to evaluate the scouting methods for larva and adults of the alfalfa weevil, $Hypera$ $postica$ Gyllenhal on Chinese milkvetch, $Astragalus$ $sinicus$ L. in the field. Three sampling methods, shake-bucket, shake-picking, and a sweeping net were evaluated for collecting alfalfa weevil larvae. We found significant differences among scouting methods and date in all survey fields. Sweep-net sampling was less able to detect small larvae than large larvae, which were not detected until early April whereas the shake-bucket, and shake-picking methods efficiently collected larvae from middle March. A Pitfall trap with three different baits - no bait, kidney bean seeds and sprouting kidney beans were compared for collection efficiency of alfalfa weevil adults. Collection efficiencies were significantly different by bait(p<0.018). Traps baited with sprouting kidney beans were the most efficient for collecting the alfalfa weevil. The number of alfalfa weevil caught was not significantly different between kidney bean seed and no bait in the pitfall trap. Therefore, the shake-bucket method for larvae and a pitfall trap baited with sprouting kidney beans for adults are recommended for scouting of the alfalfa weevil in a Chinese milkvetch field.

• Nuclear Engineering and Technology
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• v.43 no.3
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• pp.257-270
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• 2011

A set of reflood tests has been performed using ATLAS, which is a thermal-hydraulic integral effect test facility for the pressurized water reactors of APR1400 and OPR1000. Several important phenomena were observed during the ATLAS LBLOCA reflood tests, including core quenching, down-comer boiling, ECC bypass, and steam binding. The present paper discusses those four topics based on the LB-CL-11 test, which is a best-estimate simulation of the LBLOCA reflood phase for APR1400 using ATLAS. Both homogeneous bottom quenching and inhomogeneous top quenching were observed for a uniform radial power profile during the LB-CL-11 test. From the observation of the down-comer boiling phenomena during the LB-CL-11 test, it was found that the measured void fraction in the lower down-comer region was relatively smaller than that estimated from the RELAP5 code, which predicted an unrealistically higher void generation and magnified the downcomer boiling effect for APR1400. The direct ECC bypass was the dominant ECC bypass mechanism throughout the test even though sweep-out occurred during the earlier period. The ECC bypass fractions were between 0.2 and 0.6 during the later test period. The steam binding phenomena was observed, and its effect on the collapsed water levels of the core and down-comer was discussed.

• Nuclear Engineering and Technology
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• v.45 no.7
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• pp.941-950
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• 2013

The Korean Nuclear-Hydrogen Technology Development (NHTD) Plan will be performing irradiation testing of coated particle fuel at HANARO to support the development of VHTR in Korea. This testing will be carried out to demonstrate and qualify TRISO-coated particle fuel for use in VHTR. The testing will be irradiated in an inert gas atmosphere without on-line temperature monitoring and control combined with on-line fission product monitoring of the sweep gas. The irradiation device contains two test rods, one has nine fuel compacts and the other five compacts and eight graphite specimens. Each compact contains about 260 TRISO-coated particles. The irradiation device is being loaded and irradiated into the OR5 hole of the in HANARO core from August 2013. The device will be operated for about 150 effective full-power days at a peak temperature of about $1030^{\circ}C$ in BOC (Beginning of Cycle) during irradiation testing. After a peak burn-up of about 4 atomic percentage and a peak fast neutron fluence of about $1.7{\times}10^{21}\;n/cm^2$, PIE (Post-Irradiation Examination) of the irradiated coated particle fuel will be performed at IMEF (Irradiated Material Examination Facility). This paper reviews the design of test rod and irradiation device for coated particle fuel, and discusses the technical results for irradiation testing at HANARO.

• The Korean Journal of Zoology
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• v.13 no.2
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• pp.51-56
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• 1970

Studies on the feeding and resting behavior of Culex pipiens pallens, a possible vector of Japanese encephalitis in Korea, was carried out at Kobu-Ri, Kobu-Myon, Chongup Kun. Cholla Pukdo in 1967. 1. Indoor and outdoor human biting collections showed that 47.3 per cent Culex pipiens pallens were collected indoors and 52.7 per cent outdoors. 2.Feeding occurred throughout the night from dusk to dawn, with the peak period from 23:00-24:00 hours outside the house and from 24:00-01:00 hours inside. 3. Culex pipiens pallens females preferred man for their blood feeding to domestic animals. The results of human and cow biting collections showed that the feeding ratio between man and cow was 2.1 to 1. As to the feeding preference to the domestic animals, the ratio among cow, pig and horse was 7.3 to 5.1 to 5.4 4. Daytime resting collections showed that large numbers of Culex pipiens pallens females rest inside the house, especially in the bed room and the chicken pen. As temperatures increased, fewer mosquitoes resting indoors and more mosquitoes rest ing outdoors were caught. By means of sweep-net collections at outdoors resting places, a small number of Culex pipiens pallens mosquitoes were caught in such places as grass fields, vegetable fields, barley fields, bean fields, culverts, bomb shelters, and so on. A comparison between number of mosquitoes collected resting during the day in bedrooms and verandahs with resting collections in the same places at night showed that more mosquitoes were present at night. It was observed that the majority of the unfed females rested before feeding at night.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.256-265
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• 1995

The effect ground-cover weeds on the occurrence of apple pests and their natural enemies was studied in an apple orchard in Ahnsung, Kyung-gi do during seasons of 1993 and 1994. The major apple pests and their parasitoids and predators were surveyed on the apple tree canopy in tow experimental plots; a weed-free lot where all weeds were removed by herbicide treatment, and a mowed plot where weeds were allowed restrictly by cutting with an asickle. Also, a sweep net sampling was taken from ground-cover weeds in the mowed plot. There were no significant differences in the abundance of mite and aphids between two plots, although mite densities tend to be lower in the mowed plot. The apple leaf miner, Phyllonorycter ringoniella, was significantly fewer in the mowed plot,. The densities of natural enemies of mites and aphids were slightly higher in the mowed plot. The parasitism of apple leaf miner in the mowed plot was 6~10% and 20~25% higher than that in the weed-free plot in 1993 and 994, respectively. Several natural enemies such as Apanteles kuwayamai (Braconidae), Orius sauteri (Anthocoridae), Chrysopa sp. (Chrysopidae), coccinellidae, and Eulophidae were collected both from weeds and the apple trees, However, potential apple pests were not observed on weeds. The development of insect community on the apple tree canopy was restricted by the pesticide spray on apple trees, while the insect community on weeds was maintained without significant destruction by pesticides spray on apple trees. Consequentely, the ground-cover weeds under apple trees affected occurrences of apple pests and their natural enemies in apple trees. te specialist natural enemies such as apple leaf miner's parasitoids dispersed from weeds to the apple canopy and affected apple leaf miner density significantly. However, generalist predators that have preys available on weeds stayed on weeds, hence their control effects for mites and aphids on the apple canopy were low.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.111-129
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• 2012

Terrestrial insect fauna was surveyed in the Junam wetland area, which consists of the Junam, Dongpan, and Sannam wetlands, by visual counting and pictures. A sweep net collection was conducted from May to October 2010. A neighburing artificial lotus wetland was also surveyed for comparison. A total of 5,730 insects were surveyed, representing 268 species in 85 families and 12 orders. Sixty-three species of coleopterans were surveyed, followed by 60 species of Lepidoptera, and 37 species of Hemiptera. Coleopteran individuals were 25.9% of the total insect numbers surveyed, comprising most abundant group. This was followed by Odonata, Lepidoptera, and Orthoptera at 22.3%, 15.4%, and 12.7%, respectively. In total, 197 species were surveyed in the Dongpan wetland, 175 in the Junam wetland, and 154 species in the Sannam wetlands. However, only 86 species were surveyed in the artificial lotus wetland. Galerucella nipponensis in Coleoptera, Crocothemis servilia mariannae in Odonata, and Polygonia c-aureum in Lepidoptera were the most abundant in all four wetlands. Community analyses showed that the dominance index was highest in the artificial lotus wetland at 0.25 and lowest in Junam wetland at 0.08. Diversity indices were relatively high in all wetlands at 4.48, 4.44, 4.28, and 3.87 in Junam, Dongpan, Sannam, and the artificial lotus wetland, respectively. The insect fauna similarity index was highest in the Junam and Dongpan wetlands at 0.96. The lotus wetland showed the lowest similarity of the three wetlands with values of 0.45-0.53.