• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.63-70
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• 2012

This study was conducted to investigated the distribution, ecological character and life cycle of Black Soldier Fly(BSF), Hermetia illucens, to determine effects of BSF on composing ability to the livestock feces. The distribution of BSF was defined in all parts of the country in Korea. Its main habitat was found to be areas near cattle sheds, feces sheds, living waste dump grounds, and food waste dump grounds. Excellent species of the bio-conversion using the livestock feces were selected out of two kinds of solider flies(Hermetia illucens and Ptecticus tenebrifer). And effects of BSF on composing ability to the livestock feces were pig feces 0.5 g, cattle feces 0.43 g and chicken feces 0.3 g per a larvae of BSF. In the examination of the ability of BSF to decompose food waste, volume of the livestock feces decreased by weight pig feces 77, cattle feces 83.62 and chicken feces 80%. Observed characteristics of BSF larvae and pupae stage were by developmental stage may be summarized as follows: size and length of larvae and pupae of BSF were higher than in pig feces and mixed sawdust treatments. In order to develop artificial indoor rearing techniques, The pupation and emergence rate were not visible the difference but important factor of the mating and egg-laying was a sun light. And it was visible the difference in mating ratio. Mating rate of H. illucens by seasonal change was the highest from May to July. Mating mostly occurred between 10 : 00 and 12 : 00 during which light intensity is high. As the egg-laying medium for artificial egg collection, calf feed and food waste were most effective. The ratio of egg-laying medium is waste food : sawdust(1 : 1) in volume. For egg-laying materials, flower foam and wood with holes were used; holes sized 3 ~ 5 mm in diameter, 7 ~ 10 mm in depth were most preferred for egg-laying.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.227-237
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• 2013

The black soldier fly (BSF), Hermetia illucens, is a generalist detritivore that is usually exploited for recycling environmental wastes, including food remnants. These insects can also be used to produce antibiotics for medical applications. For this purpose, flies need to be mass-reared using an automatic rearing system that generates various sounds. Insects use sound as a means of communication for mating or warning against predators. Thus, extrinsic sounds may interrupt the normal physiological processes of insects. In this study, we analyzed the physiological changes due to various sound treatments at $25^{\circ}C$ and 8:16 h (L:D) photoperiod. At 95 dB, larvae were exposed to different sound frequencies (0-5,000 Hz). The treated larvae were adversely affected by the high-frequency sounds and showed significant reduction in pupation and adult emergence. Different sound intensities (0-105 dB) at 5,000 Hz caused significant changes in the pupation and survival of the adults at 85 dB or above. Under a stress sound condition (5,000 Hz, 95 dB), the BSF larvae exhibited aberrations in the expression of genes related to the immune system and digestion. These results indicate that high-frequency sound treatments at or above 85 dB act as a stress sound to BSF development.

• Journal of Life Science
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• v.26 no.12
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• pp.1409-1414
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• 2016

In the larvae of the black soldier fly, Hermetia illucens, innate immunity mechanisms are activated in response to various pathogens and stimulants, resulting in the expression of antimicrobial peptides (AMPs). To induce the mass production of AMPs, H. illucens fifth instar larvae were immunized with five different kinds of bacteria. We isolated from the hemolymph of the H. illucens larvae after bacterial challenge, and their antimicrobial activities against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) were measured using the inhibition zone assay. Among these five different kinds of bacteria, the hemolymph of Bacillus subtilis-challenged H. illucens larvae showed the strongest antimicrobial activity against both Gram-positive bacteria and Gram-negative bacteria. The antimicrobial activity of the hemolymph of $1{\times}10^9cfu/ml$ B. subtilis-challenged H. illucens peaks at 24 hr at 48 hr post-infection and gradually declines with time. Moreover, the immunized hemolymph also showed strong antimicrobial activity against various poultry pathogens such as S. enteritidis, S. typhimurium, and S. pullorum. These results suggest that the expression of AMP genes in B. subtilis-challenged H. illucens is up-regulated by innate immune responses, and that B. subtilis-challenged H. illucens overexpressing AMPs may be useful as a feed additive in livestock diets to reduce the need for antibiotics.

• Mycobiology
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• v.38 no.1
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• pp.7-12
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• 2010

A green mold species that has not previously been reported in Korea was isolated from oak log beds used for shiitake (Lentinula edodes) cultivation that were infested by mushroom flies. In this study, we identify the mold species as Gliocladium viride (an anamorph of Hypocrea lutea) and describe its mycological properties. The fungus was cottony on both potato dextrose agar (PDA) and Czapek yeast extract agar (CYA), but was colored white on PDA and became yellowish green and brown on CYA. Mycelial growth on PDA attained a diameter of 73 mm at $30^{\circ}C$ after 5 days. The fungus grew faster on malt extract agar (> 80 mm, 5 days at $25^{\circ}C$) compared to CYA and PDA (< 68 mm, 5 days at $25^{\circ}C$). Penicillate conidiophores of the fungus are hyaline, smooth walled, branching above typically in four stages, and $120\sim240\;{\mu}m$ in length. Club-shaped or slender phialides are formed on the metulae. Conidia of the fungus were ovate and elliptic, yellowish brown and green, and $2.5\sim3.0\;{\mu}m\times1.8\sim2.3\;{\mu}m$ in size. Typically, slimy conidia are formed in a mass and colored brown to dark green to almost black. The internal transcribed spacer rDNA and translation elongation factor 1 alpha gene sequences of the fungus isolated here show 99% identity with previously identified G. viride strains.

• Fire Science and Engineering
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• v.31 no.1
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• pp.50-57
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• 2017

The present article discusses the response characteristics of smoke detector chamber due to dust and wind velocity. Although situations have improved in terms of early sensing of fires as the smoke detectors are applied indoors, studies tend to place insufficient focus on the side effects and malfunction that can be caused by diversified life dust produced indoors and environmental requirements, etc. Therefore, in the present study, 4 types of photoelectric smoke detectors with different forms and structures of smoke chamber were selected as the experimental objects, and dust test was conducted with fly ash, talcum powder and fiber dust as experiment samples to study indoor applicability of the smoke detectors in terms of their response to diversified dust and wind velocity. Also, to observe response characteristics due to pollution level inside the smoke chamber, wind velocity for dust test were set additionally at 0.25 m/s, 0.5 m/s, and 1.0 m/s. Based to the experimental results, fly ash, talcum powder, and fiber dust (black hair powder) were found to be suitable at the dust test reference wind velocity conditions of 0.25 m/s for both operation test and non-operation test after dust application. On the other hand, under the harsh wind velocity conditions of 0.5 m/s and 1.0 m/s, malfunction of unwanted alarm was observed in non-operation tests in the case of fly ash and talcum powder, and non-operation was confirmed to occur in the case of fiber dust as the alarm failed to operate normally in operation tests.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.94-101
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• 2009

The physical properties of artificial aggregates made from clay and inorganic wastes with poor plasticity depends largely on forming method. The artificial aggregates composing of coal fly ash, stone sludge and clay were fabricated using 4 different forming methods and those physical properties were comparatively analyzed. The surface of aggregates made through the extrusion forming process was dense and smooth but was rough for the aggregates obtained by crushing a tile-shaped green body. The aggregates made by pelletizing process had a weak green strength and bumpy surface. The shell generated at surface during a high temperature sintering process induced the most aggregates to be bloated due to a dense shell. But the aggregates made through pelletizing process with dense surface layer showed no significant change in bulk density with sintering temperatures. The water absorption of aggregates decreased with sintering temperature, and that of pelletized specimen was standing $1.8{\sim}2.2$ times higher than that of made by other forming methods. It is concluded that the aggregates having various properties could be fabricated from one batch by using different forming methods.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.1
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• pp.171-174
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• 2009

The black soldier fly larvae are able to decompose various organic wastes such as livestock manures and food wastes. We tested whether the quality of the insect derived compost, i.e. larval feces, was comparable to that of a commercial fertilizer. The results show that the chemical composition and the growth rate of cabbages grown on the insect derived compost are virtually identical to those on the commercial fertilizer. Therefore the insect derived compost will be an ideal substitute to commercial fertilizers.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.181-185
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• 2012

Chymotrypsin serine protease is one of the main digestive proteases in the midgut of and is involved in various essential processes. In a previous study, a gene encoding a chymotrypsin-like protease, Hi-SP1, was cloned from the larvae of Hermetia illucens and characterized. In this study, we produced the recombinant chymotrypsin-like protease Hi-SP1 in Escherichia coli cells. The molecular weight of the recombinant Hi-SP1 was estimated to be approximately 26 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western-blotting. Chymotrypsin activity was detected when AAPF was used as the substrate. Examination of the effects of temperature and pH revealed that the proteolytic activity of recombinant Hi-SP1 decreased markedly at temperatures above $30^{\circ}C$, and the optimum pH was found to be 10.0.

• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.209-246
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• 2015

Morphological features of larvae and pupae of twelve species of Simulium (Simulium) from Korea are investigated and redescribed. Detailed descriptions of immature stages of each species are provided with photographs. For the Korean members of subgenus Simulium, combinations of the following characteristics can be used to separate them from other Korean subgenera: larval abdomen without a pair of conical-shaped ventral tubercles; postgenal cleft variously shaped, viz., miter shaped, spearhead, bullet shaped or triangular; rectal papillae 3 simple lobe or compound lobes; pupal gill of 6-16 filaments; cocoon shoe, boot or slipper shaped; and head trichomes 3 pairs (1 facial+2 frontal). Habitat information and other ecological aspects of each species are provided. Updated keys to larvae and pupae of the Korean species of the subgenus Simulium are also provided to facilitate species identification. Taxonomic treatment based on external morphologies of larvae and pupae of Korean species of the subgenus Simulium are focused and included in this study. To understand their interspecific relationships, phylogenetic analyses using multiple data from molecule, morphology, and ecology are warranted in future research. Also continued exploration for new character systems is needed to establish more stable boundaries for subgenus and species delimitations.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.53-64
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• 2002

This paper describes a design of cryptographic processor that implements the AES (Advanced Encryption Standard) block cipher algorithm, "Rijndael". An iterative looping architecture using a single round block is adopted to minimize the hardware required. To achieve high throughput rate, a sub-pipeline stage is added by dividing the round function into two blocks, resulting that the second half of current round function and the first half of next round function are being simultaneously operated. The round block is implemented using 32-bit data path, so each sub-pipeline stage is executed for four clock cycles. The S-box, which is the dominant element of the round block in terms of required hardware resources, is designed using arithmetic circuit computing multiplicative inverse in GF($2^8$) rather than look-up table method, so that encryption and decryption can share the S-boxes. The round keys are generated by on-the-fly key scheduler. The crypto-processor designed in Verilog-HDL and synthesized using 0.25-$\mu\textrm{m}$ CMOS cell library consists of about 23,000 gates. Simulation results show that the critical path delay is about 8-ns and it can operate up to 120-MHz clock Sequency at 2.5-V supply. The designed core was verified using Xilinx FPGA board and test system.