• Title/Summary/Keyword: gun

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Aerodynamic Effects of Gun Gas on the Aircraft's Armament System (항공기 무장시스템 Gun Gas 공력특성에 관한 연구)

  • Choi, Hyoung Jun;Kim, Seung Han
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.623-629
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    • 2020
  • This study examined the airflow field around a gun port on the flight condition of gunfire to verify the aircraft performance and safety effects and gun gas rate, path according to the options of diverter configuration. The gun port diverter not only effectively lowered the heat generated by gunfire but also effectively discharged the gun gas upwards. The path of gun gas can be changed according to its configuration. According to the optional configuration of the rear-gun-port diverter, the flow rate, path, and pressure of the gun gas were analyzed during gunfire. An analysis of the internal velocity distribution and the temperature change of the gun port revealed a rapid decrease in flow rate through the rear diverter according to the option configuration. The forward flow rate showed a similar tendency with little change. This ensures that the gun gas generated during gunfire has a sufficient flow distance from the aircraft surface, regardless of the rear gun port diverter's optional configuration. The flow stagnation of gun gas according to the option configuration of diverter had a great influence on the internal temperature rise of a gun port.

The characteristics of cotton production of Damyang-gun & Hwasun-gun, Yeongsan River, in modern times - Focused on the comparison of Gurye-gun, Seomjingang River - (근대시기 영산강 유역(담양군과 화순군) 면직물 생산 문화의 특징 - 섬진강 유역의 구례군과의 비교를 중심으로 -)

  • Choi, Seung yeun
    • The Research Journal of the Costume Culture
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    • v.24 no.4
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    • pp.471-482
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    • 2016
  • This study investigated the characteristics of cotton production of Damyang-gun & Hwasun-gun, Yeongsan River compared with that of Gurye-gun, Seomjingang River in modern times. To do this, research method was both literature and fieldwork research, results were as follows. First, as for cotton fiber cultivation in Damyang-gun & Hwasun-gun, Chinese cotton (在來綿) has been cultivated during Japanese Colonial era unlike Gurye-gun. Especially, Yellow cotton (黃綿) has been cultivated in Hwasungun. Second, as for spinning in Damyang-gun, Hwasun-gun and Gurye-gun, some of cotton spinning process have been gradually changed to mechanization by market shop equipped with mechanized cotton gin and cotton whipping tool since Japanese colonial era. Third, the loom types also, like spinning tools, have been changed from the traditional Korean back-strap loom to the treadle loom in Damyang-gun, Hwasungun and Gurye-gun. Chemical dyeing with chemical dyestuff also has been done since Japanese Colonial era. Fourth, since the 1970s, the outputs of cotton production have been reduced in both Damyang-gun & Hwasun-gun. For Damyang-gun, this has been connected with bamboo craft since the Joseon Dynasty period. So, Damyang-gun has more concentrated on bamboo craft than cotton production. For Hwasun-gun, since Japanese Colonial era, sericulture has been very important. So, Hwasun-gun also has more concentrated on sericulture than cotton production. The main reason to discontinue cotton production in Damyang-gun, Hwasun-gun and Gurye-gun was related to the local choice like economic added value.

Resoures Plants Distributed in the Warm-temperature Zone of Jeonnam Province (전남지방에 분포하는 난대 자원식물 - 희귀특산 목본식물을 중심으로 -)

  • You, Han-Choon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.23-23
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    • 2019
  • There are many island areas in Jeonnam Province and various plants are naturally grown due to their regional characteristics. Among them 217species were found to be Rare-Specialty plants in Jonnam Province. There are growing 35 species of Critically Endangered(CR), 37 species of Endangered Species(EN), 54 species of Vulnerable(VU) and 36 species of Least Concern(LC), many of which are native to islands far south or western of the sea. This report briefly describes the geographical distribution location and the state of reproduction among Rare-Specialty woody plants grown in the Warm-temperature Zone of Jeonnam Province. There are growing Michella compressa(Shinan-gun), Actinidia rufa(Wando-gun), Glochidion chodoense(Jindo-gun), Rhus ambigua(Yeosu), Wikstroemia ganpi (Goheung-gun, Yeosu) among of the 35 Critically Endangered species. Woody plants of Endangered Species(EN) are growing Albizia kalkora(Mokpo, Muan-gun), Daphne kiusiana(Shinan-gun), Marsdenia tomentosa(Wando-gun), Osmanthus insuralis(Yeosu, Shinan-gun). Woody plants of Vulnerable(VU) are growing Ardisia crenata(Wando-gun, Shinan-gun), Hibiscus hamabo(Wando-gun), Illicium anisatum (Jindo-gun), Koelreuteria paniculata(Wando-gun), Wikstroemia ganpi(Youngam-gun). Woody plants of Least Concern(LC) are Celtis choseniana(Yeosu), Chionanthus retusus(Wando-gun, Goheung-gun), Cinnamomum camphora(Wando-gun, Jindo-gun), Linder sericea(Boseong-gun).

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A Study on the Effect of Administrative Districts Separation to the Changes of Population and Industry in a Region: A Case Study on Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do (행정구역 분리가 지역의 인구와 산업 변화에 미친 영향에 대한 연구: 충청북도 괴산군과 증평군을 사례로)

  • Shin, Yeong-Jae
    • Journal of the Korean Geographical Society
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    • v.51 no.3
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    • pp.381-399
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    • 2016
  • Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do have been separated administratively since 2003. Goesan-gun is rural area, and Jeungpyeong-gun is urban area. The purpose of this study is to observe changes after the separation of administrative districts (Goesan-gun and Jeungpyeong-gun, Chungcheongbuk-Do). This study observed changes of Goesan-gun and Jenugpyeong-gun, Chungcheongbuk-Do based on population, the highest land value, employees and location quotient. Population of Goesan-gun has decreased, and that of Jeungpyeong-gun has increased. The highest land value of Jeungpyeong-gun has increased more than that of Goesan-gun. Observation of location quotient, with the location quotient of 2013 as a criterion, showed that manufacturing business and producer service business have developed in Jeungpyeong-gun, while agriculture and customer service business have developed in Goesan-gun. This result is due to the difference between regional characteristic of Goesan-gun and Jeungpyeong-gun.

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Process Quality Improvement through Improving Measurement System for Internal Diameter of Gun Barrel (포신 내경 측정시스템 개선을 통한 공정품질 향상)

  • Park, Young Min;Bae, In Hwa;Kim, Sang Boo
    • Journal of Korean Society for Quality Management
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    • v.51 no.4
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    • pp.633-642
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    • 2023
  • Purpose: The variation of the internal diameters of gun barrel incurs a lot of reworks in gun barrel manufacturing process and the significant quality problem of gun barrel. And it is likely to stem from the current measurement system for the internal diameter of gun barrel and the related manufacturing process as well. The purpose of this study is to improve the gun barrel manufacturing process through improving measurement system. Methods: The improved measurement system using laser can measure the internal diameters of gun barrel more accurately, and the properly adjusted honing process reduces the variation of internal diameters of gun barrel. Results: Comparing the mean square error of internal diameters for 6 gun barrels measured before and after process improvement shows that the variation of gun barrel internal diameters was significantly reduced after the process improvement. Conclusion: The introduction of improved measurement system for the internal diameters of gun barrel and the adjustment of related honing process results in the reduction of reworks of gun barrels and their internal diameter variations.

Study on Manufacturing Actual Mal-gun from Joseon Dynasty -Based on the Excavated Mal-gun from Seok-nam-dong, In-chceon- (조선시대[朝鮮時代] 말군의 실물 제작법에 관한 연구)

  • Jeong, Mi-Sook;Song, Mi-Kyung
    • Journal of the Korean Society of Costume
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    • v.57 no.7
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    • pp.153-161
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    • 2007
  • In 2004, Mal-gun(抹裙) was excavated from a plastered tomb in Seok-nam-dong, In-cheon. This tomb is assumed to be from an upper-class woman. The excavated Mal-gun was used to fill in the empty spaces in coffin, and it was seriously damaged and foxed dark. The Mal-gun is made with thin, loose Sook-cho(숙초), and the width of the fabric is 70cm. Both sides of the crotches are overlapped in front, and the back is opened. The waist straps are detached, leaving a little part to show the width of the straps. The hems of the Mal-gun are sewed straight, without any pleats, except some spaces for the feet to go through. This study compared the Mal-gun of Joseon Dynasty from the documentary records and picture records with the excavated Mal-gun from Seok-nam-dong, In-chceon. Also, actual Mal-gun was manufactured according to the excavated Mal-gun to study the process of manufacturing and the formation. As a result, the excavated Mal-gun has the same form of that shown in Ak-hak-gwae-bum, a documentary record from the early period of Joseon Dynasty.

Concept of Servo Gun (Servo Gun의 개요)

  • 문태예
    • Journal of Welding and Joining
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    • v.17 no.4
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    • pp.1-5
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    • 1999
  • Servo Gun은 기존의 일반적인 Spot용접Gun에서 가압 및 개방에 사용되는 Air Cylinder를 Servo Motor로 대치한 신개념의 Spot용접Gun으로 여러 가지의 우수한 기능과 특징을 가지고 있어 적 용범위의 확대가 기대되고 있다.

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Infection Status with the Metacercariae of Heterophyid Trematode in Mullet and Goby Collected from Western Coastal Areas of Cholla-do, Korea

  • Sohn, Woon-Mok;Moon, Byung-Chul
    • Biomedical Science Letters
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    • v.7 no.1
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    • pp.31-37
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    • 2001
  • The present study was performed to investigate the infection status of heterophyid fluke metacercariae in mullets and gobies collected from some coastal areas of cholla-do. The collected fishes were transferred to the laboratory, artificially digested with pepsin-HCI solution and examined under a stereomicroscope. In 70 mullets examined, the metacercariae of Heterophyes nocens (in 28.6% of fish), Heterophyopsis continua (in 2.9%), Pygidiopsis summa (in 32.9%) and Stictodora spp. (in 14.3%) were detected. The metacercariae of H nocens were detected in mullets from Shinan-gun (in 60.0% of fish), Muan-gun (in 54.4%), Hampyong-gun (in 25.0%) and Yonggwang-gun (in 16.7%). The average metacercarial density per infected fish were 7.6,34, 10 and 5 in each areas. A total of 7 metacercariae of H. continua was detected in only 2 mullets from Hampyong-gun. The metacercariae of p. summa were detected in mullets from Haenam-gun (in 80.0% offish), Muan-gun (in 27.3%), Hampyong-gun (in 16.7%) and Puan-gun (in 100%). The average metacercarial density per infected fish were 350, 14, 5 and 97 in each areas. The metacercariae of Stictodora spp. were detected in mullets from Shinan-gun (in 26.7% offish), Hampyong-gun (in 33.3%) and Puan-gun (in 20.0%). The average metacercarial density per infected fish were 2.8, 18.8 and 2.5 in each areas. In 70 gobies examined, the Metacercariae of H nocens (in 15.7% of fish), H continua (in 47.1%) and Stictodora spp. (in 48.6%) were detected. The metacercariae of H. nocens were detected in gobies from Shinan-gun (in 50.0% of fish) and Yonggwang-gun (in 10.0%). The average metacercarial density per infected fish were 71 and 2 in each areas. The metacercariae of H. continua were detected in gobies from Shinan-gun (in 65.0% of fish), Hampyong-gun (in 70.0%) and Yonggwang-gun (in 60.0%). The average metacercarial density per infected fish were 5.7,6.6 and 3.2 in each areas. The metacercariae of Stictodora spp. were detected in gobies from Shinan-gun (in 80.0% offish), Hampyong-gun (in 70.0%) and Puan-gun (in 40.0%). The average metacercarial density per infected fish were 149,203 and 5.5 in each areas. From the above results, it was confirmed that the mullet and goby from some coastal areas of cholla-do are infected with numerous metacercariae of heterophyid trematodes.

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Infections with Zoonotic Trematode Metacercariae in Yellowfin Goby, Acanthogobius flavimanus, from Coastal Areas of Republic of Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk;Cho, Shin-Hyeong;Ju, Jung-Won;Lee, Soon-Won;Seok, Won-Seok
    • Parasites, Hosts and Diseases
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    • v.56 no.3
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    • pp.259-265
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    • 2018
  • To investigate the infection status of zoonotic trematode metacercariae in yellowfin goby, Acanthogobius flavimanus, from coastal areas of the Republic of Korea (Korea), we examined total 344 gobies from 21 localities with an artificial digestion method from 2013 to 2017. The metacercariae of Stictodora lari were most frequently detected in 45.3% goby from 7 localities, i.e., Taean-gun (Chungcheongnam-do), Gochang-gun (Jeollabuk-do), Muan-gun, Shinan-gun, Haenam-gun (Jeollanam-do), Hadong-gun and Goseong-gun (Gyeongsangnam-do). Their infection rates were 90.0%, 66.7%, 46.7%, 8.0%, 3.3%, 26.7%, and 86.7% and intensities were 1,090, 6.2, 1.6 1.0, 2.0, 2.0, and 7.2 metacercariae per fish infected respectively. Heterophyopsis continua metacercariae were found in 38.2% goby from 6 localities, i.e., Gochang-gun, Muan-gun, Shinan-gun, Gangjin-gun, Boseong-gun (Jeollanam-do) and Goseong-gun, and their intensities were relatively low, 1-21 metacercariae. Stictodora fuscata metacercariae were detected in 61.3% goby from 4 localities, i.e., Taean-gun, Gochang-gun, Hadong-gun and Goseong-gun. Their infection rates were 90.0%, 53.3%, 5.9%, and 73.3% and intensities were 1,081, 3.1, 3.0, and 10.2 metacercariae per fish infected respectively. Heterophyes nocens metacercariae were found in 55.0% goby from Muan-gun and Shinan-gun. Total 3 metacercariae of Isthmiophora hortensis were detected in 2 (8.0%) gobies from Shinan-gun. Total 15 metacercariae of Centrocestus armatus were detected in 5 gobies (33.3%) from Gyeongpo-ho (ho means lake) in Gangneung-si, Gangwon-do. The present study suggests that yellowfin goby, A. flavimanus, acts as the infection sources of zoonotic intestinal flukes in western and southern coastal areas than in eastern coastal areas of Korea.

A Study on Village Names of Youngnam Provinces : the Cases of Changnyeong-Gun, Bonghwa-Gun and Namhae-Gun (영남지방 지명에 관한 연구 -창녕군, 봉화군, 남해군의 경우-)

  • Park, Tae-Hwa
    • Journal of the Korean association of regional geographers
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    • v.5 no.1
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    • pp.1-24
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    • 1999
  • This is a study on village names in a plain region of Changnyeong-Gun, a mountain region of Bonghwa-Gun and an island region of Namhae-Gun. The three regions differ in geographical features. The data are based on 455 village names in Changnyeong-Gun, 552 village names in Bonghwa-Gun and 275 village names in Namhae-Gun found in the 1 : 50,000 topographic map. The method of this study is to analyze the word structures of village names in the five basic concepts in geography : Man-Land(Natural Environment and Human Activities). Spatial Relation, Distribution, Region and Transition. The main results of this study are as follows: 1. Naming of villages are related to Natural Environment(41%), Human Activities(23%), Region(17%), Spatial Relation(13%), Distribution(5%), and Transition(3%). Of these six factors, Changnyeong-Gun is relatively dominant in village names related to Spatial Relations, Region and Transition ; Bonghwa-Gun Natural Environment and Namhae-Gun Human Activities and Spatial Relations. But the three Guns are absolutely dominant in village names related to Natural Environment and Human Activities. 2. A village name is divided into the specific name part(given name) and the generic name part(classified name). Names related to Human Activities, Spatial Relations, Distribution and Transition are more frequently found in the specific name part. Therefore, they are used as the given name of a village name. Whereas names related to Natural Environment and Region are more frequently found in generic name part, which means that they are used as the classified name of a village. 3. The word structure of a village name usually has two parts a frontal part(given name) and a rear part(classified name). The two parts have a particular pattern in the geographic concept when they are combined. 1) In the village names related to in their frontal part of the word structure, is more frequently combined as their rear part in Bonghwa-Gun, in Namhae-Gun and in Changnyeong-Gun. 2) In the village names related to in their frontal part of the word structure, is more frequently combined as their rear part in Changnyeong-Gun, in Namhae-Gun and in Bonghwa-Gun. Accordingly, Man(Human Activities) - Land (Natural Environment) can be considered the most important concept in the naming of villages, because the concept is most frequently used in the word structures of village names.

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