• 제목/요약/키워드: group structure

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Composite locomotive frontend analysis and optimization using genetic algorithm

  • Rohani, S.M.;Vafaeesefat, A.;Esmkhani, M.;Partovi, M.;Molladavoudi, H.R.
    • Structural Engineering and Mechanics
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    • 제47권5호
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    • pp.729-740
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    • 2013
  • This paper addresses the structural design of the front end of Siemens ER24 locomotive body. The steel structure of the frontend is replaced with composite. Optimization of the composite lay-up is performed using Genetic Algorithms. Initially an optimized single design for the entire structure is presented. Then a more refined optimum is developed by considering the separate optimization of 7 separate regions of the structure. Significant savings in the weight of the structure are achieved.

The Regulatory Domain of Troponin C: To Be Flexible or Not To Be Flexible

  • Gagne, Stephane M.;Sykes, Michael T.;Sykes, Brain D.
    • 한국자기공명학회논문지
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    • 제2권2호
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    • pp.131-140
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    • 1998
  • The calcium-induced structural changes in the skeletal muscle regulatory protein troponin C (NTnC) involve a transition from a ‘closed’to an ‘open’structure with the concomitant exposure of a large hydrophobic interaction site for target proteins. Structural studies have served to define this conformational change and elucidate the mechanism of the linkage between calcium binding and the induced structural changes. There are now several structures of NTnC available from both NMR and X-ray crystallography. Comparison of the calcium bound structures reveals differences in the level of opening. We have considered the concept of a flexible open state of NTnC as a possible explanation for this apparent discrepancy. We also present simulations of the closed-to-open transition which are in agreement with the flexibility concept and with experimental energetics data.

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The crystal structure of pirprofen$(C_{3},\; H_{14},\; ClNO_2$), a non-steroidal antiinflammmatory agent

  • Kim, Yang-Bae;Park, Il-Yeong
    • Archives of Pharmacal Research
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    • 제19권1호
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    • pp.71-73
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    • 1996
  • The molecular structure of pirprofen, 3-chloro-4-(2,5-dihydro-1H-pyrrol-1-yl)-.alpha.-methyl-benzeneacetic acid, was determined by single crystal X-ray diffraction analysis. The compound was recrystallized from a mixture of chloroform and toluene in triclinic, space group P over $\bar1,\; with\; a=4.577(1),\; b=11.213(2),\; C=12.485(2){\AA},\alpa.=107.39(1),\;\beta=97.79(1),\;\gamma=92.03(2),\; and Z=2$ The calculated density is $1.384 g/cm^3$. The structure was solved by the direct method and refined by full matrix least-squares procedure to the final R value of 0.034 for 1681 independent reflections. The non-aromatic dihydropyrrol group is found to be coplanar to the central aromatic ring. The molecules are dimerized through the intermolecular hydrogen bonds at the carboxyl group in the crystal.

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외항화물운송기업의 재무적 특성에 관한 연구 - 대기업군과 중소기업군의 비교를 중심으로 - (A Study on the Financial Statements Analysis of Ocean-going Shipping Companies)

  • 오태형
    • 무역상무연구
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    • 제69권
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    • pp.389-406
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    • 2016
  • The Purpose of this study is to analyze the financial statements of ocean-going shipping companies that have experienced financial difficulties since the global financial crisis. Specifically, the study conducts comparing major firm with small and medium-sized firm from fianancial point of view, analyzes the different trends of two groups. As a result, this paper finds the different characteristics between two groups. There were known many financial difficulties in ocean-going shipping companies, but this is not applied to small and medium-sized firm group. Small and medium-sized firm group grew soundly and slowly during research period. But major firm group experienced the deficit and their management condition has deteriorated considerably during that period. To cope with this difficulties, major firm group should take self-effort to improve fianacial structure and establish the risk management system.

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Effects of Inplane Modes in SEA on Structure-Borne Noise Transmission in Ship Structures

  • Kim, Jae-S.;Kim, Hyun-S.;Kang, Hyun-J.;Kim, Sang-R.
    • Journal of Hydrospace Technology
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    • 제2권1호
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    • pp.18-26
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    • 1996
  • It is normal practice to consider bending wave modes only, when one applies SEA (Statistical Energy Analysis) to ship structures because of complexities in SEA modeling and evaluation of coupling loss factors for inplane modes. According to the result of Tratch[1], the inplane wave modes becomes important for the analysis of a foundation structure as the distance from the source and receiver increases. In this paper, the effect of inplane wave modes on structure-borne noise propagation in ship structures is presented. It is shown that the inplane wave could increase the noise level more than 10 dB compared with the results without inplane wave modes at high frequency bands for compartments far from the source location.

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건설가설공사의 표준기술분류체계 구축 (Development of Technical Breakdown Structure Standard in Temporary Works)

  • 박준모;김옥규;박길범
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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    • pp.162-163
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    • 2013
  • A temporary work are lifting equipment that tower crane or lift, and temporary architectures that office building and storage in construction site. And it is main construction work that built and used temporarily like to a scaffolding, a walk plate, and a formwork. This study is to adjust breakdown structure of temporary work to introduce technical tendency. With a site manager, it is collected a detailed statement and compared. As a result to break down a tendency that temporary equipment, additional function, and direct work of temporary technique, first, existing detail technical indexes that group I, group J, group K, and group L are classified. Second, due to set up and manage to main agents in case of existing detail technical indexes that B1, B2, it is not wrong to classify. But, it is somewhat different, and therefore adjust it to same level. Finally, as a technical tendency that temporary equipment, additional function, and direct work of temporary technique, it is adjusted the others.

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Layered structure of sialoliths compared with tonsilloliths and antroliths

  • Buyanbileg Sodnom-Ish;Mi Young Eo;Yun Ju Cho;Mi Hyun Seo;Hyeong-Cheol Yang;Min-Keun Kim;Hoon Myoung;Soung Min Kim
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제50권1호
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    • pp.13-26
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    • 2024
  • Objectives: The aim of this study was to perform a comparative analysis of the ultrastructural and chemical composition of sialoliths, tonsilloliths, and antroliths and to describe their growth pattern. Materials and Methods: We obtained 19 specimens from 18 patients and classified the specimens into three groups: sialolith (A), tonsillolith (B), and antrolith (C). The peripheral, middle, and core regions of the specimens were examined in detail by histology, micro-computed tomography (micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and transmission electron microscopy (TEM). Results: In the micro-CT, group A showed alternating radiodense and radiolucent layers, while group B had a homogeneous structure. Group C specimens revealed a compact homogeneous structure. Histopathologically, group A showed a laminated, teardrop-shaped, globular structure. Group B demonstrated degrees of immature calcification of organic and inorganic materials. In group C, the lesion was not encapsulated and showed a homogeneous lamellar bone structure. SEM revealed that group A showed distinct three layers: a peripheral multilayer zone, intermediate compact zone, and the central nidus area; groups B and C did not show these layers. The main elemental components of sialoliths were O, C, Ca, N, Cu, P, Zn, Si, Zr, F, Na, and Mg. In group B, a small amount of Fe was found in the peripheral region. Group C had a shorter component list: Ca, C, O, P, F, N, Si, Na, and Mg. TEM analysis of group A showed globular structures undergoing intra-vesicular calcification. In group B, bacteria were present in the middle layer. In the outer layer of the group C antrolith, an osteoblastic rimming was observed. Conclusion: Sialoliths had distinct three layers: a peripheral multilayer zone, an intermediate compact zone and the central nidus area, while the tonsillolith and antrolith specimens lacked distinct layers and a core.

Seismic response and failure modes for a water storage structure - A case study

  • Bhargava, Kapilesh;Ghosh, A.K.;Ramanujam, S.
    • Structural Engineering and Mechanics
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    • 제20권1호
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    • pp.1-20
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    • 2005
  • The present paper deals with the seismic response analysis and the evaluation of most likely failure modes for a water storage structure. For the stress analysis, a 3-D mathematical model has been adopted to represent the structure appropriately. The structure has been analyzed for both static and seismic loads. Seismic analysis has been carried out considering the hydrodynamic effects of the contained water. Based on the stress analyses results, the most likely failure modes viz. tensile cracking and compressive crushing of concrete for the various structural elements; caused by the seismic event have been investigated. Further an attempt has also been made to quantify the initial leakage rate and average emptying time for the structure during seismic event after evaluating the various crack parameters viz. crack-width and crack-spacing at the locations of interest. The results are presented with reference to peak ground acceleration (PGA) of the seismic event. It has been observed that, an increase in PGA would result in significant increase in stresses and crack width in the various structural members. Significant increase in initial leakage rate and decrease in average emptying time for the structure has also been observed with the increase in PGA.

THE STRUCTURE OF A CONNECTED LIE GROUP G WITH ITS LIE ALGEBRA 𝖌=rad(𝖌)⊕ 𝔰𝒍(2,𝔽)

  • WI, MI-AENG
    • 호남수학학술지
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    • 제17권1호
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    • pp.7-14
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    • 1995
  • The purpose of this study is to construct the structure of the connected Lie group G with its Lie algebra $g=rad(g){\oplus}sl(2, \mathbb{F})$, which conforms to Stellmacher's [4] Pushing Up. The main idea of this paper comes from Stellmacher's [4] Pushing Up. Stelhnacher considered Pushing Up under a finite p-group. This paper, however, considers Pushing Up under the connected Lie group G with its Lie algebra $g=rad(g){\oplus}sl(2, \mathbb{F})$. In this paper, $O_p(G)$ in [4] is Q=exp(q), where q=nilrad(g) and a Sylow p-subgroup S in [7] is S=exp(s), where $s=q{\oplus}\{\(\array{0&*\\0&0}\){\mid}*{\in}\mathbb{F}\}$. Showing the properties of the connected Lie group and the subgroups of the connected Lie group with relations between a connected Lie group and its Lie algebras under the exponential map, this paper constructs the subgroup series C_z(G)

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