• Korean journal of applied entomology
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• v.31 no.1
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• pp.45-49
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• 1992

Studies were conducted to control Spodoptera exigua in Allium fistulosum field using synthetic sex pheromone trap. Heavily, medium and lightly damagd fields at early transplanting time showed no differences in control effects after 8 weeks of establishment of pheromone traps in Allium fistulosum fields. Number of damaged leaves in each treated field was 0.2-3 individuals per 60 hills comparing with 33.2 individuals at non-treated field. Also, the numbers uf male adults attracted to pheromone traps were 1.8-5.0 individuals at the big inning of installation but increased to 25.8, 49.9, 74.9, and 77.4 individuals after 2, 4, 6, and 8 weeks, respectively. There was a negative correlation between amount of male adults attracted to pheromone traps and number of damaged leaves (r=-0.9572*). Number of adults attracted to various colored light trap for 30 days were 6 in red, 11 in white and none in blue comparing with 1,041 individuals in pheromone trap.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.125-132
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• 2003

Seasonal fluctuations in density of mosquito species were investigated at two cow sheds near to a large, reedy marsh with fairly polluted brackish water near the coast of Yongam-ri, Cheongryang-myon, Ulsan, Korea. Female mosquitoes were collected biweekly using Nozawa light traps from March to September, from 1999 to 2001. On average, 4,416.1, 5,505.9 and 6,863.8 females per trap night were collected from 10 species in 5 genera in 1999, 2000 and 2001, respectively. Among them, An. sinensis was most abundant (53.4% in species ratio), followed by Cx. tritaeniorhynchus (43.0%), Cx. inatomii (1.6%), Ochlerotatus dorsalis (1.3%) and Cx. pipiens pallens (0.5%). A malaria vector, An. sinensis and a Japanese encephalitis vector, Cx. tritaeniorhynchus were collected 3,663.3 females and 3,142.5 females per trap night from June to September for the years, respectively. According to the biweekly population changes at the area, Cx. inatomii which was dominant species in 1997, was the most abundant in the early July during 1999-2001.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.77-82
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• 2001

Flying behavior during nighttime and control methods of fruit sucking pests were investigated in yuzu (Citrus junos) groves at Koheung area from August to November in 1999. Among the 3 kind of bulbs with different color (white, blue and yellow), white bulb attracted the most number of fruit sucking pests . The 93 percent of the moths was attracted from sunset to 24 o\`clock. Main flying time of hemipteriods in early, mid, and late October were from 22 to 04 o\`clock, sunset to 02 o\`clock and sunset to 24 o\`clock, respectively. Their flying time become earlier as the night temperature declines. For control of fruit sucking pests, attraction liquid traps, light traps (100 W) and illumination light bulb were set up in the yuzu groves (1,000 $\m^2$) from the 1 st October to the 3rd November. Attraction liquid was composed of a raw rice wine 2,000 ml+black sugar 100 g+vinegar 100 ml. When established at 3 sites per 1,000 $\m^2$ orchard, attraction liquid trap reduced the number of sucking spots on yuzu fruit to 64% and its attracting effect maintained for 3 weeks after setting-up. Three light traps per 1,000 m2 which turned on from sunset to 02 o\`clock reduced the number of sucking spots by 60% .

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.674-682
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• 2018

Large industrial motors require a large area because of the high risk of shutdown accidents and large industrial accidents due to the lowering of the dielectric strength of the armature windings and overheating problems. Therefore, there is a demand for a large-capacity motor that has small size, light weight, and excellent dielectric strength compared with conventional motors. Superconducting motors have advantages of high efficiency and output power, low size, low weight, and improved stability. This results from greatly increasing the magnetic field generation by using superconductive field coils in rotating machines such as generators and motors. It is very important to design and analyze the cooling system to lower the critical temperature of the wires to achieve superconducting performance. In this study, a field loss analysis and low-temperature heat transfer analysis of the cooling system were performed through the conceptual design of a 100-HP high-temperature superconducting synchronous motor. The field loss analysis shows that a uniform pore magnetic flux density appears when high-temperature superconducting wire is used. The low-temperature heat transfer analysis for gaseous neon and liquid neon showed that a flow rate of 1 kg/min of liquid neon is suitable for maintaining low-temperature stability of the high-temperature superconducting wire.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.105-115
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• 2018

The comstock mealybug is one of the serious insect pest in pear. It is necessary effective control methods such as attractive sex pheromone. Using sex pheromones is necessary for studying the physiology and ecology of insect pests. In the present study, the sex pheromone of comstock mealybug was used for investigating the flying acts of the adult male. As temperature increased, the development period of eggs shortened, but it was longer at $30^{\circ}C$. The mean number of eggs laid was 482 at $25^{\circ}C$ and males constituted 37% of the experimental population at $30^{\circ}C$. The flight of the male comstock mealybug was mostly restricted to a 2-4 hour period after sunrise, even if condition of light period is changed. Male mealybugs were incapable of upwind flight towards an attractant when air velocity was 1.5 mph. Preference of height was tested in a pear orchard. The ineffective heights of the traps were 2 and 2.5 m, whereas the effective heights were 1 and 1.5 m. Many captured males at 0.5, 1, and 5 m, and the number of captured males were similar in 10, 15, and 20 m. Male mealybugs were captured up to a distance of 50 m, suggesting that it is possible to control the male mealybugs that are more than 50 m away when sex pheromone traps are used.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.157-163
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• 2017

The object segmentation approach has the merit of reducing the processing cost required to detect moths of interest, because it applies a moth detection algorithm to the segmented objects after segmenting the objects individually in the moth image. In this paper, an object segmentation method for moth detection in pheromone trap images is proposed. Our method consists of preprocessing, thresholding, morphological filtering, and object labeling processes. Thresholding in the process is a critical step significantly influencing the performance of object segmentation. The proposed method can threshold very elaborately by reflecting the local properties of the moth images. We performed thresholding using global and local versions of Ostu's method and, used the proposed method for the moth images of Carposina sasakii acquired on a pheromone trap placed in an orchard. It was demonstrated that the proposed method could reflect the properties of light and background on the moth images. Also, we performed object segmentation and moth classification for Carposina sasakii images, where the latter process used an SVM classifier with training and classification steps. In the experiments, the proposed method performed the detection of Carposina sasakii for 10 moth images and achieved an average detection rate of 95% of them. Therefore, it was shown that the proposed technique is an effective monitoring method of Carposina sasakii in an orchard.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.107-112
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• 2002

Seasonal occurrence pattern of the peach pyramid moth (PPM), Dichocrosis punctfferahs, was studied by sex pheromone traps and mercury light traps in several Fuyu persimmon orchards under different control pressures in southern region of Korea in 2000 and 2001. Fruit damage by the larvae was also checked at harvesting time from 1999 to 2001. The pattern showed 3 distinct peaks; the 1st one in mid to late June, the 2nd one in mid to late August, and the 3rd one in late September. Number of PPM catches was higher in less controlled than in intensively controlled orchards. There were no persimmon fruits damaged by the larvae of PPM and persimmon fruit moth, Stathmopoda masinissa, in our samples from the testing orchards at harvesting time. Therefore, it is unlikely that these two quarantine pests are included in the exporting fruits. Considering flora adjacent to the tested orchards and zero levels of fruit damage by the larvae, there is a strong possibility that the moths flew from neighbouring chestnut trees or other host plants to be attracted to the traps in the persimmon orchards.

• Journal of the Korean Chemical Society
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• v.28 no.4
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• pp.251-258
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• 1984

The mechanism of photosensitization and the affect of binder on dye-sensitized ZnO have been studied by surface photovoltage spectroscopy. It has been found that the value of energy trapping level $E_{t1}$ on ZnO is 1.12eV (${\lambda$ = 1,100nm) and that of energy trapping level $E_{t2}$ on dye-sensitized ZnO is 0.99eV (${\lambda$ = 1,250nm) which is shifted towards a longer wavelength. The effect of binder on ZnO has been increased the efficiency of surface photovoltage, but it does not effect the values of energy trapping level. The acid-type dyes agree well with the prediction based on an electron transfer mechanism. The desensitization of the Na salt-type dyes for the intrinsic photoresponse of zinc oxide can be explained by energy transfer mechanism. It has been obtained that the dye-sensitized ZnO indicates the possibility of electrophotographic photosensitizer for the infrared range of light.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.457-460
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• 2014

Toxicity of several insecticides was tested against the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), and adult Gymnosoma rotundatum (Diptera: Tachinidae) in a sweet persimmon orchard. H. halys was captured using black light traps and G. rotundatum adults were collected using sticky traps lured with an aggregation pheromone, methyl-(E,E,Z)-2,4,6-decatrienoate of Plautia stali. Five insecticides, namely, bifenthrin 2 WP, buprofenzine+dinotefuran (20+15) WP, clothianidin 8 SC, dinotefuran 10 WP, and thiamethoxam 10 WP, were moderately toxic to G. rotundatum, resulting in 55.3% to 74.3% mortality. Bifenthrin 2 WP caused 93.1% mortality at 72 h within cages as a residual toxicity, and others caused varied mortalities.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.4
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• pp.32-37
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• 2010

One of the most common engineering processes using plastics is the injection molding. In addition, plastics are utilized over the entire areas in our life including cars and home appliances among others for their characteristics with no deterioration even after a long time, as well as for their light weights in addition to their good durability. This paper aimed to minimize defects through prior analyses on the weld line, air traps, filling time, molding temperature and deformation patterns among others while carrying out interpretations on the cooling, filling and deformation in the injection process using the moldflow for rear lamp reflectors among components for a car in making parts through the coating process after injection.