• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5579-5585
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• 2015

In FFT(Fast Fourier Transform) implementation, DIT(Decimation-In-Time) and DIF (Decimation-In-Frequency) methods are mostly used. Among them, various DIF structures such as Radix-2/4/8 algorithm have been developed. Compared to the DIF, the DIT structures have not been investigated even though they have a big advantage producing a sequential output. In this paper, a butterfly structure for DIT Radix-8 algorithm is proposed. The proposed structure has smaller latency time because of Radix-8 algorithm in addition to the advantage of the sequential output. In case of 4096-point FFT implementation, the proposed structure has only 4 stages which shows the smaller latency time compared to the 12 stages of Radix-2 algorithm. The proposed butterfly can be used in FFT block required the sequential output and smaller latency time.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.337-339
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• 2005

In Iksan, Korea, Parnara guttata Brener et Grey spend three generations per year, 1st generation adult emerged mid to late May from pupa developed from overwintered larva in weeds on bank around rice paddy field or on hillside and moved to rice paddy field to lay eggs on leaves of rice. The damage to rice by 2nd generation larva began to increase late July and reached peak from mid to late August. The 3rd generation adults were observed early to mid September and flew away from rice paddy field. There was significant relationship between the transplanting time and the occurrence of P. guttata in rice paddy fields. P. guttata preferred the rice transplanted in late season in paddy field. Insecticide treatment on late July about a week before the peak larval occurrence reduced the damage by P. guttata up to 91.2%, whereas the treatment on early August was a lot less effective reducing only 57.2% of the damage.

• The Korean Journal of Zoology
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• v.11 no.4
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• pp.121-123
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• 1968

지난 11月 13日 (음 8月 23日) 저녁에 서울大學校 敎授會館에서 韓國動物學會와 有志들의 주최로 石宙明 先生의 追悼會 및 遺稿 "濟州道 隨筆"의 出版記念會가 있었는데, 이날은 바로 石 先生의 回甲날이며 1950年 10月 6日, 43歲의 젊은 나이로 이 세상을 떠나시게 된지 18년이 지난 날이었다. 이 자리에는 石 先生의 친척, 친지, 제자 등 50 여명이 참석하여 하였는데, 動物學者로서의 先生, 山岳人으로서의 先生, 에페스란토語 애용자로서 先生, 스승으로서의 先生 등 여러면으로 故人의 옛 모습을 이야기 해가면서 조용히 그분을 追慕하였다. 石先生은 1908年 11月 13日 (음 9月 23日) 平壤에서 탄생하셨으며, 1926年 開城 松都中學校, 1929年에 日本 鹿兒島 高等農林學校를 졸업하셨다. 1931年 母校인 松都中學校 敎員으로 취임하신 후 10여년 동안 교편을 잡으시면서 昆蟲 특히 나비의 연구를 하셨다. 1943年부터 京城帝大 附屬 濟州道 生藥硏究所所長으로 계시다가, 1945年 水原農事試驗場 病理昆蟲學部長을 거쳐 1946年부터 國立科學博物館 動物學部長으로 재직하면서 연구 생활을 계속하셨다. 石 선생하면 나비 博士로 통하리 만큼 수없이 많은 나비를 만지고 연구하셨으며 그 이름은 국제적 으로도 알려져 있다. 이것은 학문에 대한 그분의 熱情이 비범하였음을 뜻한다. "나는 행복한 사람이야, 세상에 자기 취미와 직업이 一致되어 있는 사람이 제일 행복한 사람인데 나는 그렇거든$\\cdots\\cdots$"라고 石 선생이 말씀하신 바와 같이 직업면에 있어서는 퍽 행복스러웠던 것같다. 선생은 "부스러기 시간"을 잘 이용하셨다는데 선생이 전문 이외의 分野에 관해서도 박식하였던 것은 多才多能한 天性 때문일 뿐만 아니라 시간을 잘 이용하는 부지런한 성품 때문이기도 하리라. 선생은 걱정해도 소용이 없는 일은 걱정 안하는 성품이었기에 퍽 樂天的이셨다. 그래서 그런지 떠들썩하게 웃으시는 때가 많았다. 石先生은 비교적 짧은 기간에 많은 업적을 남기셨다. 80여篇 動物學 分野의 論文을 발표하였을 뿐만 아니라 濟州道 方言集(1947), 제주도 文獻集(1949) 등도 출판하셨다. 그 밖에 隨筆, 紀行文을 쓰신 것도 많다. 또한 濟州道 昆蟲相, 濟州道 資料集, 朝鮮産 蝶類 分布圖, 世界博物學年表 등 未刑인 채로 남아 있는 遺稿도 있다고 한다. 다음 石先生이 發表하신 論文의 目錄을 적어서 先生의 업적을 다시 한번 찬양하는 동시에 生物學徒의 참고로 하려한다.다시 한번 찬양하는 동시에 生物學徒의 참고로 하려한다.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.326-332
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• 2009

A faunistic study on the terrestrial insects of Unmunsan(located in the boundary between Unmun-myeon Chongdo-gun Gyoungbuk and Sannae-myeon Milyang-si Gyoungnam, Korea) was carried out during November, 2007 to October, 2008. It was found that terrestrial insects distributed in nature sabbatical area of Unmunsan, were composed of 14 orders, 151 families, 610 genera, 756 species. In this study, it shows the dominances of taxa from site U1 to U4, in order of the following: Lepidoptera, Coleoptera and Hymenoptera. Lepidoptera with 252 species and 33.3% show the highest dominance and Coleoptera follows the former with 182 species and 24.1% in dominance. The rare Luciola lateralis Motschulsky and Spindasis takanonis (Matsumura) which is designated as the endangered species level II by the Ministry of Environment inhabit in Unmunsan.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.3
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• pp.103-110
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• 2008

In this paper, an efficient butterfly structure for 8K/2K-Point Radix-4 FFT algorithm using CORDIC(coordinate rotation digital computer) is proposed. It is shown that CORDIC can be efficiently used in twiddle factor calculation of the Radix-4 FFT algorithm. The Verilog-HDL coding results for the proposed CORDIC butterfly structure show 36.9% cell area reduction comparison with those of the conventional multiplier butterfly structure. Furthermore, the 8K/2K-point Radix-4 pipeline structure using the proposed butterfly and delay commutators is compared with other conventional structures. Implementation coding results show 11.6% cell area reduction. Due to its efficient processing scheme, the proposed FFT structure can be widely used in large size of FFT like OFDM Modem.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.35-50
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• 2022

In this review, the compositions of the sex pheromones of 22 lepidopteran species were analyzed and briefly arranged by comparing the research results conducted in different locations worldwide. These compositions can be used as monitoring tools for pests of rice, maize, leguminous crops, perilla, and sesame in Korea. The sex pheromone compounds and those compositions of four species were successfully identified within Korean populations. The optimal compositions of sex pheromones of three other species were selected through behavioral studies using synthetic chemicals of the known pheromone compounds in laboratories and fields, without chemical identification processes in the sex pheromone compounds of Korean populations. For a few species, the roles of the minor components of the sex pheromone volatiles should be re-assessed for use in the development of optimal monitoring lures.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.98-106
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• 2011

Establishing conservation programs to protect and maintain populations of endangered species are not only a global trend, but also a pursuit endorsed by the Korean Environmental Conservation Act. This study evaluates the feasibility of alternative habitat patches for the endangered butterfly Parnassius bremeri. A portion of habitat of P. bremeri is expected to be fragmented and damaged due to the scheduled construction of the Sangju-Yongduk Highway. A trans fer of the habitat patches of P. bremeri is also scheduled. In order to select an alternative habitat patch, the Mark-Release-Recapture (MRR) method was used to simulate a patch transfer model. The connectedness between habitat are as and the survival of local populations were evaluated for each candidate habitat. It was found that metapopulations with patch distances of <250m showed a 50% connectedness and survival rate in local populations. P. bremeri were expected to migrate at an average distance of 300m. In addition, P. bremeri formed a metapopulation that exhibited intimate patch dynamics that promoted persistence among these patches. Possible candidate habitats including those recommended by local governing bodies were evaluated along with habitats that may counter problems arising from the damage done to the original habitat and habitats that may have a compensatory value equal to that of the original habitat. Based on these criteria, Ansa-myeon township office was selected due to its high scores. This scoring was based on a consideration of a wide range of variables that mark a successful transfer of habitat. These include the amount of funding available, the governing bodies of the possible alternative habitat, and the Expected collaborative effort of local citizens. This decision was collaborated on by incorporating the expertise of various fields of study including biology, ecology, biogeography, ecological engineering, landscape architecture, and social sciences. Therefore, it is suggested that in order to evaluate an alternative habitat for organisms, many social issues as well as ecological issues must be considered.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.3 s.151
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• pp.412-424
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• 2006

This paper starts out with a review of the concepts of naturalism and natural clothes. Based on these concepts, the paper aims to create nature-friendly and high-value modem designs by grafting natural images from butterflies into human bodies. The images of butterflies are combined to show distinguished luxury and diversity with natural materials such as denim. As for the design technology, Adove Illustrator 10, Photoshop 7.0, and Prima Vision Textile Design System are used since they are very popular in the CAD system. The followings are the main findings of our research. Naturalism displays its objectivity based on its inherent interest in human nature and its factual description in scientific approaches with an intention to find a true meaning of human life in nature. Natural clothes can be defined as the clothes of natural silhouette which are made of pure materials in natural colors and dyes from natural motifs such as animals, plants or natural phenomena. We have realized that the visually distinguished looks of butterflies are indeed far more luxurious than those of any other insects and this visual distinction can be utilized to attract the attention from designers. Lastly, it turns out that the digital printing technique can create more variety in colors and design forms than the manual printing, thereby providing designers with more options and practicality.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.4
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• pp.378-383
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• 2013

A butterfly throttle valve has been used to control the brake power of an SI engine by controlling the mass flow-rate of intake air in the induction system. However, the valve has a serious effect on the volumetric efficiency of the engine due to the pressure resistance in the induction system. In this study, a new intake air controlling valve named "Variable Geometry Throttle Valve(VGTV)" is proposed to minimize the pressure resistance in the intake system of an SI engine. The design concept of VGTV is on the application of a venturi nozzle in the air flow path. Instead of change of the butterfly valve angle in the airflow field, the throat width of the VGTV valve is varied with the operating condition of an SI engine. In this numerical study, CFD(computational fluid dynamics) simulation technique was incorporated to have an aerodynamics performance analysis of the two air flow controlling systems; butterfly valve and VGTV and compared the results to know which system has lower pressure resistance in the air intake system. From the result, it was found that VGTV has lower pressure resistance than the butterfly valve. Especially VGTV is effective on the low and medium load operating condition of an SI engine. The averaged pressure resistance of VGTV is about 49.0% lower than the value of the conventional butterfly throttle valve.

• 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.