• 한국농공학회논문집
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• 제60권2호
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• pp.13-24
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• 2018

As food consumption pattern changes (reduced rice consumption and increased consumption of fresh vegetables), managing upland fields became a greater priority. However, the agricultural infrastructure projects have been focused on rice farming, and the infrastructure level to support dry fields cultivation is insufficient. The purpose of this study was to spatial distribution analysis of these dry fields with farm manager registration information. Using FRAGSTATS, we analyzed landscape indices (TA/CA, NP, PD, LSI, LPI, PLADJ, COHESION, CONNECT, AI) of farmlands in which farmers in 13 regions (Si or Gun) cultivated dry-field crops. As results of this analysis, the total area of the fields in Naju-si, Hampyeong-gun and Suncheon-si were found to be wider, but the average area of a patch in Youngam-gun, Hampyeong-gun and Jangseong-gun were wider than other regions. On average, each farmer had farmlands containing of 1.7~2.4 patches and cultivated crops in fields of 0.2~0.5 ha. Farmlands of Hampyeong-gun, Youngam-gun, Naju-si showed high values in adjacency indices, however the farmlands of Suncheon and Gwangyang showed fragmented distribution with low values in adjacency indices. These results of fragmentation analysis of farmlands could be used when we establish the plan of an agricultural infrastructure project or select places for a collaborative agricultural management business promotion project.

• 한국항공우주학회지
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• 제31권9호
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• pp.103-109
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• 2003

액체 로켓 엔진의 개발 과정 중 필연적으로 선행 연구가 수행되어야 하는 연소 안정성 평가 시험(Stability Rating Test)을 위한 펄스건의 국내 자체 개발을 시도하였다. 개발 초기 단계에서의 몸체의 파열 현상을 해결하기 위해 재질을 변경하고 몸체의 두께를 증가시켰다. 또한 기밀성 유지를 위하여, 멤브레인을 장착하여 기폭 시험전의 기밀 시험을 수행하였으며, 기밀 시험 치구를 제작하여 기폭 후의 기밀을 확인하였다. 실제 SRT를 수행하기 위해서는 펄스건의 cavity 홀더 부분의 재사용이 바람직하므로, 이를 해결하기 위해 재설계/재시험 과정이 수행되었다. 이러한 일련의 시험을 통하여 기폭 푸에도 접촉면 상태가 매우 양호한 SRT 적용 부품이 홀더의 디자인을 확정하여 펄스건 개발을 완료하였다.

• 대한조선학회논문집
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• 제54권6호
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• pp.522-529
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• 2017

Air gun shock system is used as an alternative energy source as part of the attempt to overcome the restrictions of economical expense and environmental damage, etc., due to the use of explosives for the UNDerwater EXplosion (UNDEX) shock test. The objectivity of this study is to develop the simulation technique of air gun shock test for the design of model-scale one for the near field non-explosive UNDEX test through its verification with full-scale SERCEL shock test result. Underwater blasting response analysis of full-scale air gun shock test was carried out using highly advanced M&S (Modeling & Simulation) system of FSI (Fluid-Structure Interaction) analysis technique of LS-DYNA code, and was verified by comparing its shock characteristics and behaviors with the results of air gun shock test.

• Human Ecology Research
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• 제56권4호
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• pp.407-416
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• 2018

This study investigated the characteristics and changes of Jeongbang-village silk culture Jeollanam-do Province during Japanese Colonial Rule with a focus in on Gokseong-gun & Damyang-gun Jeongbang-village. The results of the study are as follows. First, after Japanese occupation, it changed from a traditional silkworm species, the Joseon Silkworms and the mulberry tree to an improved Japanese species. Japan established a silk spinning mill called Jongyeon Textile factory in Gwangju and Jeongbang Village was formed in poor rural areas. Second, the way of village management consisted of buying a large number of land for mulberry plans and creating mulberry fields as a cheap way to utilize the labor force for women and men in rural areas. Third, since the end of the Japanese colonial era, mulberry fields in Jeongbang villages which the Japanese left, were sold at a cheap price to Koreans. After the Korean War, the Korean government's efforts to modernize the silkworm industry resulted in a continuous plan to increase the number of silkworms. The impact of government policies has also increased the production of silkworms in these areas. However, since the early 1980s, Korean companies have been affected by Japanese economic policies and dumping by China that has resulted in in a sharp decline in their production. In the case of Gokseong-gun and Damyang, the production of silk products was halted and switched to other crops in the early 1990s when the farming industry began to decline.

• Parasites, Hosts and Diseases
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• 제34권2호
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• pp.107-112
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• 1996

참굴큰입흡충(Gymnophalloides seoi)의 국내 분포상황을 알기 위하여 동해안 남해안 및 서해안 등 여러 해안 지역에서 참굴을 채집한 후 참굴큰입흡충 피낭유충 감염상황을 조사하였다. 전라남도 신안군의 13개 면과 신안군 외 14개 군(경기도, 전라북도, 전라남도, 경상남도, 경상북도, 강원도)의 씨개 면을 대상지역으로 하였고. 굴의 피낭유충 감염 여부 및 감염량을 조사하였다. 신안군 13개 면 중 압해면 및 안좌면을 포함한 10개 면의 굴에서 피낭유충 감염이 확인되었고 지역별 감염률은 1.7-100%이었다. 그 중 압해면산 굴이 개체당 평균 785.9개의 피낭유충을 보유하고 있어 감염량이 가장 높았다 신안군 이외의 24개 면 중에서는 전라북도 부안군 변산면만 제외하고 모두 음성의 결과를 나타내었으며, 부안군 변산면에서는 굴 50개 중 1개에서 피낭유충 15마리가 검출되었다. 이번 연구 결과로 보아 참굴큰입흡충의 농후한 유행은 전라남도 신안군에 국한된 것으로 보이며, 전라북도 부안군 등 인근 지역에 약간의 유행이 있는 것으로 판단되었다.

• 한국재난정보학회 논문집
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• 제11권1호
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• pp.23-34
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• 2015

본 연구에서는 충청북도 내 각 지자체를 대상으로 지역별 대설특성을 통한 잠재적 위험요인을 분석하였다. 분석결과, 35년 평균적설량으로 인한 잠재적 위험도는 제천시와 보은군이 가장 높았으며 35년 최대적설량을 통한 잠재적 위험요인에서는 다른 결과가 도출되는 것을 알 수 있었다. 잠재적 위험요인에 대한 지역의 빈도수를 살펴보면 가장 높은 지역은 보은군, 제천시, 괴산군, 영동군, 청주시 순으로 도출되었다. 본 연구는 일반적인 대설특성 뿐만 아니라 잠재적인 위험요인들을 도출하고 그에 대한 위험도를 제시하였다는 점에서 그 의의를 가진다. 본 연구의 결과는 향후 충청북도 각 지자체들의 제설대응체계 및 방안 마련에 기초자료로 활용할 수 있을 것이다.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.105-108
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• 2018

Recently matured silkworm powder was developed by RDA. In this study, the effect of pulverizing method on the particle size of matured silkworm powder was examined. FESEM was performed to observe the morphology and to measure the particle size of silkworm powder. Particle morphology of air-jet mill pulverized powder was round and smooth, however, those of roller-mill and hammer-mill pulverized mature silkworm was more harsh and square. Particle size was varied with pulverizing technique as follows; $1.1{\mu}m$ (air-jet mill), $10{\mu}m$ (roller mill), and $120{\mu}m$ (hammer mill), respectively. A proximate analysis results of air-jet mill powder showed that crude protein, crude lipid, crude fiber, and ash was 73%, 12%, 1.95%, and 3.4%, respectively. According to our results, air-jet mell technique might be used to make a tiny matured silkworm powder.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.497-502
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• 2016

To know the infection status of zoonotic trematode metacercariae in brackish water fish, we surveyed mullets collected from 18 coastal areas in the Republic of Korea. The metacercariae of Pygidiopsis summa were detected in 236 (68.2%) out of 346 mullets examined. They were found in mullets from 15 areas except for those from Boseong-gun (Jeollanam-do), Pohang-si, and Uljin-gun (Gyeongsangbuk-do). Especially in mullets from Taean-gun (Chungcheongnam-do) and Geoje-si (Gyeongsangnam-do), their prevalences were 100% and 95.5%, and the average metacercarial density was more than 1,000 per fish. They were also detected in mullets from 3 coastal lakes, Gyeongpoho, Songjiho, and Hwajinpoho, in Gangwon-do, and their average densities were 419, 147, and 672 per infected fish, respectively. The metacercariae of 5 other heterophyid species, including Heterophyes nocens, Heterophyopsis continua, Metagonimus sp., Stictodora fuscata, and Stictodora lari, were found in the mullets examined. The metacercariae of H. nocens were detected in 66.7, 100, 28.6, 81.6, 3.9, 61.5, and 27.3% of mullets from Muan-gun, Shinan-gun, Haenam-gun, Gangjin-gun, and Boseong-gun (Jeollanam-do), Hadong-gun, and Geoje-si (Gyeongsangnam-do), and their metacercarial intensities were 64, 84, 119, 99, 1, 24, and 24 per fish infected, respectively. From the above results, it has been confirmed that P. summa metacercariae are heavily infected in mullets from coastal areas of Korea. It is suggested that residents who frequently consume raw mullet dish can be easily infected with heterophyid flukes.

• Journal of Welding and Joining
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• 제24권6호
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• pp.13-20
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• 2006

Resistance spot welding is widely used for joining sheet metals in the automotive manufacturing process. Recently, servo-gun is used to increase the productivity and precise control the acting force. However, force control mechanisms have not been investigated with servo-guns until now. In this paper, it is proved that servo-motor current is proportional to torque and by experiment, experimental equation between servo-motor current and electrode force was derived. Algorithm for feedback control of electrode force was suggested using current measurement. In addition, applying soft touch method to this system the impact between electrode and specimen, which is the problem of air gun, could be reduced. Indentation made the force decrease in holding time of resistance spot welding. In order to overcome this problem, force compensation using the servo gun was used and it improved weld strength in good welding current range.

• 한국농촌건축학회논문집
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• 제4권1호
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• pp.9-18
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• 2002

Keumsan-gun is the area where there are many mobile populations as the place to be adjacent to Daejon. There is the tendency that the empty houses at Keumsan area are increasing as 1,115 houses every year as of 2001. So, this researcher examined and analyzed the actual state by grasping the present situation of empty houses centering around Keumsan-gun. And, this researcher could obtain the following conclusion as the result that this researcher progressed the study so as to present the application scheme of empty houses. As for Keumsan-gun, farming populations are more than other city and gun at Choongcheong Southern Proince Area as the area formed with mountain groups topographically. Thus, it is forecast that the appearance of empty houses will increase, as the population decrease and the residents to have migration plan will appear higher than other city and gun in the future also. Therefore, as for the superannuated empty houses that use is impossible, to service by removing will be helpful to the image uplifting of village. In addition, as for the empty houses that use is possible, the establishment of system to connect buyers by rebuilding them as garden houses and weekend houses etc. through purchase and sale and long-term lease etc. is necessary.