• Title/Summary/Keyword: Crane-fly

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A study on the link composition design of a double link type level luffing jib crane (II) (이중 링크 형식 수평 인입 집 크레인의 링크 구성 설계에 관한 연구(II))

  • Hur, C.W.;Choi, M.S.;Moon, D.H.
    • Journal of Power System Engineering
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    • v.15 no.1
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    • pp.57-63
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    • 2011
  • It is very important to determine link composition of a crane in the basic design of the crane. There are many parameters in the design for the link composition of a double link type level luffing jib crane. We analyze the variation of link composition according to the variation of these parameters which are the angle of fixed link, the angle between the fixed link and backstay when the position of the crane is the maximum working radius, the ratio of fly jib length between two moving hinges to the total length of fly jib, the length of backstay, and the slewing radius. In this paper, we describe the application of the previous analysis program of the link composition design for a double link type level luffing jib crane.

A Study on the Link Composition Design of a Double Link Type Level Luffing Jib Crane (I) (이중 링크 형식 수평 인입 집 크레인의 링크 구성 설계에 관한 연구( I ))

  • Moon, D.H.;Hur, C.W.;Choi, M.S.
    • Journal of Power System Engineering
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    • v.13 no.1
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    • pp.19-25
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    • 2009
  • This paper is a study on the link composition design of a double link type level luffing jib crane using path generation synthesis passing through three precision points according to parameters, the length of backstay, the ratio of fly jib length between two moving hinges to the total length of fly jib, the location of a intermediate passing point etc. when the maximum and minimum working radius of the crane are given. The performance of the crane depends on the deviation of the luffing trajectory at fly jib tip. The luffing trajectories according to the above parameters are analyzed and shown in graphs by the developed computer program. In a real-life design, some trials are needed to arrive at a proper link composition design. Therefore, it is expected that the present computer program can rapidly and exactly deal with a link composition design proper to the design criteria of the crane.

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Description of Larval and Pupal Stages of Tipula (Nippotipula) sinica (Diptera, Tipulidae) from South Korea with Ecological Notes

  • Jo, JaeIck
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.1
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    • pp.56-59
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    • 2017
  • The external anatomy of the immature stages (last instar larva and pupa) of the crane fly, Tipula (Nippotipula) sinica Alexander, 1935 (Diptera: Tipulidae) is described and illustrated from specimens first collected in Korean peninsula (South Korea). Comments concerning natural history and microhabitats of larvae are provided. This is the first detailed description with illustrations for the last instar larva and pupa of Tipula (Nippotipula) sinica. Pupal characteristics resemble those of most species from advanced lineages within the subfamily Tipulinae. And, also it described with habitats and biological notes of Tipula (Nippotipula) sinica. Crane fly larvae, categorization as found in this survey indicate a taxonomic stream and are expected to help.

Determining the Position of Supporter to prevent a Overload applied to the Wedge Type Rail Clamp (과부화 방지를 위한 쐐기형 레일클램프의 지지대 위치 설정)

  • Han, Dong-Seop;Han, Geun-Jo;Lee, Seong-Wook
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.294-297
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    • 2006
  • The rail clamp is the device to prevent the crane slips along a rail from the wind blast as well as to locate a container crane in the set position during an operating mode. In this study we conduct the research for determining the proper position of supporter to prevent the overload applied to the rail clamp with respect to the wedge angle in the wedge type rail clamp. The friction force between the jaw pad and the rail to prevent that the crane slips along a rail, when the wind blows, is generated fly the rail-directional wind load. Accordingly the proper position of the supporter to prevent the overload is determined fly analyzing the forces applied to the rail clamp in the wedge working stage. In order to analyze the effect of the wedge angle on the position of supporter, 5-kinds of wedge angles, such as 2, 4, 6, 8, $10^{\circ}$, were adapted as the design parameter, and the wind speed of 40m/s was adapted as the design wind speed criteria.

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Static and Dynamic Analysis for a Double Link Type Level Luffing Jib Crane (이중링크 형식 수평인입 집 크레인의 정적·동적 해석)

  • Moon, D.H.;Hur, C.W.
    • Journal of Korean Society of Steel Construction
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    • v.12 no.6
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    • pp.715-725
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    • 2000
  • As a link composition of a double link type level luffing jib crane was determinated through the link composition design, the design to be considered will be computations of the luffing trajectory deviation at the fly jib tip and the required luffing device capacity. This paper is a study regarding the static and dynamic analysis for a mechanism of the crane. The objective of the static analysis is to determinate the capacity and the dimension of luffing device when the crane selfload, rated hoisting load, wind load and inertia force are applied on the crane. The objective of dynamic analysis is to compute the luffing trajectory deviation, velocity and inertia force due to luffing acceleration for each link. All analyses are performed by computer programs. The reliability of the program was checked by results from analyses of the related commercial package. It is expected that the productivity and reliability of the design can be improved by this program which can rapidly and exactly deal with static and dynamic analysis for a given link composition of the crane.

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Limnophila crane flies(Diptera: Limoniidae) of Korea

  • Podenas, Sigitas;Park, Sun-Jae;Byun, Hye-Woo
    • Journal of Species Research
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    • v.11 no.2
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    • pp.117-127
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    • 2022
  • This study is based on crane fly specimens collected during an 80-year period (1937-2017) in the Republic of Korea and Democratic People's Republic of Korea, and are in collections maintained at the United States National Museum, Smithsonian Institution, Washington DC, USA; the Snow Entomological Museum, University of Kansas, Lawrence, KS, USA; and the National Institute of Biological Resources, Incheon, South Korea. These crane flies are developing in wet places which usually prevail at lower altitudes, but such areas are often used for agriculture and human settlements, making natural habitats scarce and fragmented. Probably because of that, Limnophila crane flies are rare on the Korean Peninsula and were unnoticed by previous researchers. The genus Limnophila Macquart, 1834 with three species being new record for the Korean Peninsula: L. (Limnophila) japonica Alexander, 1913, L. (L.) pictipennis (Meigen, 1818) and L. (L.) politostriata Alexander, 1934a. General information are presented for each species, such as on genus and subgenus, redescriptions of species based on Korean specimens, illustrations of both sexes, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula.

New record of Pilaria crane flies(Diptera: Limoniidae) from Korea

  • Podenas, Sigitas;Park, Sun-Jae;Byun, Hye-Woo
    • Journal of Species Research
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    • v.11 no.1
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    • pp.38-46
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    • 2022
  • This study is based on crane fly specimens collected during more than 80 years, starting from 1938 through 2019, in the Republic of Korea and Democratic People's Republic of Korea and are in collections maintained at the United States National Museum, Smithsonian Institution, Washington DC, USA; the Snow Entomological Museum, University of Kansas, Lawrence, KS, USA; and the National Institute of Biological Resources, Incheon, South Korea. Pilaria crane flies are aquatic and semiaquatic, developing in fast running and stagnant water bodies and in wet muddy places at the margins of water pools. Such habitats usually prevail at lower altitudes, but these areas most often are used for agriculture and human settlement, making natural habitats scarce and fragmented. Pilaria crane flies are rare, thus it is not surprising that genus was left unnoticed by previous researchers. The genus Pilaria Sintenis, 1889 with two species P. melanota Alexander, 1922 and P. simulans Savchenko, 1983, is a new record for the Korean Peninsula. We present general information on the genus, redescriptions of species based on Korean specimens, illustrations of both sexes, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula for each species.

Phylidorea crane flies(Diptera: Limoniidae) of Korea

  • Podenas, Sigitas;Park, Sun-Jae;Byun, Hye-Woo
    • Journal of Species Research
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    • v.11 no.1
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    • pp.47-60
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    • 2022
  • This study is based on crane fly specimens collected during more than 80 years, from 1937 through 2019, and are in collections maintained at the United States National Museum, Smithsonian Institution, Washington DC, USA; at Korea University collection, Seoul, South Korea, and the National Institute of Biological Resources, Incheon, South Korea. Three species belonging to genus Phylidorea Bigot, 1854 originally were described from North Korea and in total four species were known from the Peninsula. Phylidorea (Phylidorea) multidentata (Alexander, 1938) is a Korean endemic. We are adding P. (P.) melanommata (Alexander, 1921) to the list of Korean species, which was previously recorded from Japan and Far East of Russia. We present general information on genus and subgenera, redescriptions of species based on Korean specimens, illustrations of both sexes, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula (including North Korea) for each species.

Prionolabis crane flies (Diptera: Limoniidae) of Korea

  • Podenas, Sigitas;Park, Sun-Jae;Byun, Hye-Woo;Aukstikalniene, Rasa
    • Journal of Species Research
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    • v.11 no.1
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    • pp.29-37
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    • 2022
  • This study is based on crane fly specimens collected more than 80 years ago in 1938-1939 and preserved at the United States National Museum, Smithsonian Institution, Washington DC, USA. Despite many attempts with a variety of methods, no additional specimens of this genus were captured. This likely means that that this genus is extinct on the Korean Peninsula, or its distribution is restricted to the northern areas of the Democratic People's Republic of Korea (North Korea). The genus Prionolabis Osten Sacken, 1860 with four species, one of them Prionolabis dis(Alexander, 1950) endemic to North Korea, was recorded by Ch. P. Alexander (Alexander, 1938, 1940, 1950). All succeeding papers listing these species were based on these original works without study based on actual specimens. For each species, we present general information on genus, redescriptions of species based on Korean specimens, illustrations of important taxonomical structures, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula.