• Title/Summary/Keyword: mating structure

Search Result 68, Processing Time 0.023 seconds

Analytical Research of Topside Installation in Mating phase with Crane Vessel

  • Lee, Jong-Hyun
    • Journal of Ocean Engineering and Technology
    • /
    • v.25 no.4
    • /
    • pp.1-6
    • /
    • 2011
  • The installation of a topside structure can be categorized into the following stages: start, pre-lifting, lifting, lifted, rotating, positioning, lowering, mating, and end of installation. The transfer of the module onto the floating spar hull occurs in the last three stages, from lowering to the end. The coupled multi-body motions are calculated in both calm water and in irregular waves with a significant wave height (1.52m). The effects of the hydrodynamic interactions between the heavy lifting vessel and the spar hull during the lowering and mating stages are considered. The internal forces caused by the load transfer and ballasting are derived for the mating phases. The results of the internal forces for the calm water condition are compared with those in the irregular sea condition. Although the effect of the pitch motion on the relative vertical motion between the deck of the floating structure and the topside module is significant in the mating phases, the internal force induced pitch motion is too small to have this influence. However, the effect of the internal force on the wave-induced heave responses in the mating phases is noticeable in the irregular sea condition because transfer mass-induced draught changes for the floating structure are observed to have higher amplitudes than the external force induced responses. The impacts of the module on the spar hull in the mating phase are investigated.

Evaluation of Mating Dynamic Forces of Semi-submersible Offshore Structure Topside Module (반잠수식 해양 구조물 상부 모듈의 해상 결합 작업시 동하중 평가)

  • Lee, Jin-Ho;Jung, Hyun-Soo;Kim, Byung-Woo
    • Journal of Ocean Engineering and Technology
    • /
    • v.27 no.1
    • /
    • pp.9-15
    • /
    • 2013
  • This paper calculates the mating dynamic forces of a semi-submersible offshore structure's topside module, where a hull moored in the sea is combined with a topside module carried by a heavy lift vessel, as a mating installation method. The environmental conditions include various wave directions and wave heights, with constant wind and current speeds. Appropriate ballast and de-ballast plans for the heavy lift vessel and hull of the semi-rig should be performed in order to safely obtain these forces, whereas a fixed platform or the GBS (Gravity based structure) type of offshore structure only needs a ballast plan for the heavy lift vessel. From this paper, the allowable wave height or wave direction for the mating procedure can be investigated based on the standard DAF (Dynamic amplitude factor) of the rules and regulations.

Mating Call Structure and Variation of the Frog Rana nigromaculata (참개구리(Rana nigromaculata)의 짝짓기 소리의 구조와 변이)

  • 박시룡;양서영
    • The Korean Journal of Ecology
    • /
    • v.20 no.6
    • /
    • pp.423-438
    • /
    • 1997
  • The structure and variation of the mating call in Rana nigromaculata was studied in a population at Da-rak, Chong-won, Chung-buk (36$\circ$ 37' latitude, 127$\circ$ 21' longitude) in Korea. The mating call consists of 3 to 8 pulse groups divided by clear silent intervals. Each pulse group is also composed of fine pulses. Temperature and body size affect the temporal and spectral characteristics of the mating call. Pulse, pulse group repetition rate and dominant frequency rise with increasing temperature, whereas pulse grouprepetition rate and dominant frequency decrease with increasing body size. A playback experiment was designed to establish the effect of a potential intruder on male calling. During the stimulus periods, resident males markedly decreased the pulse repetition rate, and icreased the rate of pulse groups, dominant frequency, and the number of call groups. This results indicate that this species responds in a graded fashion when interacting with other individuals.

  • PDF

An Assembly Modeling System for Dynamic and Kinematic Analysis (동역학 및 기구학적 해석을 위한 조립체 모델링 시스템)

  • 김성환;이건우
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.13 no.1
    • /
    • pp.48-58
    • /
    • 1989
  • An assembly modeling system, with which a designer can interactively create an assembly of components ready for the dynamic analysis, has been developed. In this system, an assembly model is created from the mating conditions between the components in the assembly, and then most information required for the dynamic or kinematic analysis packages are derived. For this development, the following problems have been solved; the creation of assembly data structure, the derivation of the joint information, the inference of each component's position, and the creation of the joint coordinate systems. Through this work, the designer can easily model an assembly by assigning mating conditions, and check the dynamic or kinematic performance with the automatic creation of inputs for the assembly analysis packages.

Development of a Molecular Marker Linked to the A4 Locus and the Structure of HD Genes in Pleurotus eryngii

  • Lee, Song Hee;Ali, Asjad;Ha, Byeongsuk;Kim, Min-Keun;Kong, Won-Sik;Ryu, Jae-San
    • Mycobiology
    • /
    • v.47 no.2
    • /
    • pp.200-206
    • /
    • 2019
  • Allelic differences in A and B mating-type loci are a prerequisite for the progression of mating in the genus Pleurotus eryngii; thus, the crossing is hampered by this biological barrier in inbreeding. Molecular markers linked to mating types of P. eryngii KNR2312 were investigated with randomly amplified polymorphic DNA to enhance crossing efficiency. An A4-linked sequence was identified and used to find the adjacent genomic region with the entire motif of the A locus from a contig sequenced by PacBio. The sequence-characterized amplified region marker $7-2_{299}$ distinguished A4 mating-type monokaryons from KNR2312 and other strains. A BLAST search of flanked sequences revealed that the A4 locus had a general feature consisting of the putative HD1 and HD2 genes. Both putative HD transcription factors contain a homeodomain sequence and a nuclear localization sequence; however, valid dimerization motifs were found only in the HD1 protein. The ACAAT motif, which was reported to have relevance to sex determination, was found in the intergenic region. The SCAR marker could be applicable in the classification of mating types in the P. eryngii breeding program, and the A4 locus could be the basis for a multi-allele detection marker.

Contact Stress Analysis of Helical Gear for Turbo Blower (터보블로워용 헬리컬 기어의 접촉응력 해석)

  • Hwang, Seok-Cheol;Lee, Dong-Hyong;Park, Young-Chul;Lee, Kwon-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.10 no.2
    • /
    • pp.90-95
    • /
    • 2011
  • This paper presents the study on the contact stress analysis of a pair of mating helical gears for turbo blower during rotation. Turbo blowers need high speed rotation of impeller in structure and high rate gear ratio. The use of helical gear indicated that noise was an important problem when the application involves high speeds and large power transmission. An example is presented to investigate the variation of contact stress on a pair of mating gears with contact positions. The variation of contact stress during rotation is compared with the contact stress at the lowest point of single tooth contact(LPSTC) and AGMA Equation for contact stress. In this study, the gear design considering the contact stress on a pair of mating gear is more severe than that of AGMA standard.

Sexual Reproduction in Unicellular Green Alga Chlamydomonas (수염녹두말속(Chlamydomonas) 단세포 녹조의 유성생식)

  • Lee, Kyu Bae
    • Journal of Life Science
    • /
    • v.27 no.1
    • /
    • pp.100-121
    • /
    • 2017
  • The sexual reproduction of the unicellular green alga Chlamydomonas is reviewed for a comprehensive understanding of the complex processes. The sexual life cycle of C. reinhardtii is distinguished into five main stages: gametogenesis, gamete activation, cell fusion, zygote maturation, and meiosis and germination. Gametogenesis is induced by nitrogen starvation in the environment. C. reinhardtii has two mating types: mating type plus ($mt^+$) and mating type minus ($mt^-$), controlled by a single complex mating type locus ($MT^+$ or $MT^-$) on linkage group VI. In the early gametogenesis agglutinins are synthesized. The $mt^+$ and $mt^-$ agglutinins are encoded by the autosomal genes SAG1 (Sexual AGglutination1) and SAD1 (Sexual ADhesion1), respectively. The agglutinins are responsible for the flagellar adhesion of the two mating type of gametes. The flagellar adhesion initiates a cAMP mediated signal transduction pathways and activates the flagellar tips. In response to the cAMP signal, mating structures between two flagella are activated. The $mt^+$ and $mt^-$ gamete-specific fusion proteins, Fus1 and Hap2/Gcs1, are present on the plasma membrane of the two mating structures. Contact of the two mating structures leads to develop a fertilization tubule forming a cytoplasmic bridge between the two gametes. Upon fusion of nuclei and chloroplasts of $mt^+$ and $mt^-$ cells, the zygotes become zygospores. It is notable that the young zygote shows uniparental inheritance of chloroplast DNA from the $mt^+$ parent and mitochondrial DNA from the $mt^-$ parent. Under the favorable conditions, the zygospores divide meiotically and germinate and then new haploid progenies, vegetative cells, are released.

Stiffness evaluation of elastomeric bearings for leg mating unit (LMU용 일래스토머릭 베어링의 강성평가)

  • Han, Dong-Seop;Jang, Si-Hwan;Lee, Kwon-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.12
    • /
    • pp.106-111
    • /
    • 2017
  • In this study, the stiffness of an LMU (Leg Mating Unit), which is a device required for installing the top side part of an offshore structure, was examined through structural analysis. This unit is mounted on the supporting point of the structure and is used to absorb the shock at installation. It is a cylindrical structure with an empty center. To support the vertical load, elastomeric bearings (EBs) and iron plates are laminated in layers. The stiffness of the EBs is basically influenced by the size of the bearings, but it varies with the number of laminated sheets inside the same sized structure. The relationship between the stiffener and the compressive stiffness is investigated, and its design is suggested. The stiffness of the EBs is analyzed by calculating the reaction force, while controlling the displacement. First, the relationship between the size of the reinforcing plate and the compressive stiffness is considered. Next, the relationship between the number of stacked reinforcing plates and the compression stiffness is considered. Different loads are required for each installed point. The goal is to design the compression stiffness in such a way that the same deformation occurs at each point in the analysis. In this study, ANSYS is used to perform the FE analysis.