• Title/Summary/Keyword: heavy structure

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A Basic Structural Design for large Floating Crane (대형 해상크레인의 구조 기본 설계)

  • PARK CHAN-HU;KIM BYUNG-WOO;HA MUN-KEUN;CHUN MIN-SUNG
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.05a
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    • pp.42-47
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    • 2004
  • This paper describes basic structural design for the large floating crane barge of fixed undulation type. Structural analysis is performed to divide two parts because crane barge is composed two parts, crane part of jib boom back stay and back tower and barge part to support crane part. The structural strength for jib boom structure members are in compliance with JIS B 8821 and scantling of all barge structural members are in compliance with the requirement of KR (Korean Register of Shipping) Steel Barges and Rules for Classification of Steel Ships. For the structural analysis of large floating crane, MSC/NASTRAN & MSC/PATRAN software is used.

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Characteristics of Heavy Metal Extraction by Benzamidoxime (Benzamidoxime에 의한 중금속의 추출특성)

  • 이상훈;윤영삼
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.371-377
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    • 1999
  • The effects of benzamidoxime concentration, solvents and temperature on the degree of metal extraction were investigated to apply benzamidoxime to heavy metal extraction as chelating agent. Benzamidoxime was synthesized from benzonitrile with hydroxylamine. The chemical structure of benzamidoxime was identified. The degree of heavy metal extraction was increased with increasing the concentration of benzamidoxime and decreasing the extraction temperature. Benzamidoxime was found to be an concentration of benzamidoxime and decreasing the extraction temperature. Benzamidoxime was found to be an effective extractant for Cu-extraction by benzene or chloroform. The relationship between the thermodynamic overall equilibrium constant and absolute temperature was expressed as log K = -5.56 + $855T^{-1}$. Heat of extraction, $$\Delta$H^0$ were calculated from overall equilibrium constants at various temperature and the extraction reactionby benzamidoxime was found to be exthothermic.

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A Study on the Relation between Riverbed Structure and Pollutant Concentration in Downstream of Nakdong River (낙동강 하류의 하상구조와 오염물질과의 상관관계 연구)

  • 황선출;정성욱
    • Journal of Environmental Science International
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    • v.5 no.4
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    • pp.481-494
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    • 1996
  • This study was performed to investigate the relationship between concentrations of heavy metals in sediment and the depths of 27 sampling sites along the West Nakdong river in downstream of Nakdong River. The deepest site was Kangdong bridge nearby 20ft. From here, the depth was shallowed to Chidong gradually. In each site the smaller mesh was, the liger concentration of heavy metal becomed. Concentration of Zn, Cd, Cr and Cu at inflow point of Shinoe stream was 576.016 ppm, 262.307 ppm, 68.674 ppm and 61.634 ppm, respectively, the concentration was the higest at this point. From here, it was lowered gradually. The concentration of heavy metal at inflow point of Joman river was 155.328 ppm, 56.485 ppm, 25.200 ppm and 31.172 ppm, respectively, those concentrations were liger than other points with the exception of Shinoe stream. Therefore, woman river and Shinoe stream were the major source of pollution in West Nakdong river. Among two sources Shinoe stream was more important source of pollution. West Nakdong river has become lake by Noksan floodgate because it's pollution has had influence on Bonglim.

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Evaluation of heavy-weight impact sounds generated by impact ball through classification (주파수 특성 분류를 통한 임팩트 볼 중량충격음의 주관적 평가)

  • Kim, Jae-Ho;Lee, Pyoung-Jik;Jeon, Jin-Yong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.1142-1146
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    • 2007
  • In this studies, subjective evaluation of heavy-weight floor impact sound through classification was conducted. Heavyweight impact sounds generated by an impact ball were recorded through dummy heads in apartment buildings. The recordings were classified according to the frequency characteristics of the floor impact sounds which are influenced by the floor structure with different boundary conditions and composite materials. The characteristics of the floor impact noise were investigated by paired comparison tests and semantic differential tests. Sound sources for auditory experiment were selected based on the actual noise levels with perceptual level differences. The results showed that roughness and fluctuation strength as well as loudness of the heavy-weight impact noise had a major effect on annoyance.

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Large eddy simulation of turbulent boundary layer effects on stratified fluids in a rotating conical container

  • Lee, Sang-Ki;Bae, Jun-Hong;Hwang, Eyl-Seon;M. Sadasivam
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.04a
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    • pp.75-80
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    • 2000
  • We revisit the arrested Ekman boundary layer problem, using a fully non-linear numerical model with the subgrid dissipation modeled by the large eddy simulation method (LES). The main objective of this study is to find out whether the dynamic balance of the arrested Ekman boundary layer explained by MacCready and Rhines (1991) is valid for high Reynolds number. The model solution indicates that for high Reynolds number and low Richardson number flows, the density anomaly diffusion by near-wall turbulent action may become intense enough to homogenize completely the density structure within the boundary layer, in the direction perpendicular to the sloping wall. Then the buoyancy effect becomes negligible allowing a near-equilibrium Ekman boundary layer flow to persist for a long period.

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The position servo-loop in the robot control system must be processed every sampling period by real-time

  • Ha, Young-Youl;Lee, In-Ho;Kim, Min-Soo;Kim, Jae-Hoon
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.121.1-121
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    • 2002
  • Calculation unit and peripheral units that are used to make the position controller are embedded to one chip FPGA. $\textbullet$ Feed-forward PID controller and interpolator in the calculation unit mitigate frequent context switching. $\textbullet$ The peripheral units reduce the size of the joints position control board. $\textbullet$ Because the calculation unit is designed with pipeline structure, it has the advantages to apply to the multi joints.

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Statistical Thermodynamical Properties and Adsorption Characteristics of Heavy Water (중수의 열역학적 성질과 흡착특성)

  • Chang-Hyun Jho;Hyungsuk Park;Seihun Chang
    • Journal of the Korean Chemical Society
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    • v.15 no.6
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    • pp.285-293
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    • 1971
  • The statistical thermodynamical properties of heavy water are calculated according to the transient state theory of significant liquid structure. The calculated values are shown to be in good agreement with the observed ones. The grand canonical ensemble partition function for the adsorbed phase of heavy water on graphite surface is derived using the theory. The adsorption isotherm, the surface pressure, the molar entropy and the molar internal energy for the adsorbed phase and then the molar heat of adsorption are calculated according to the derived partition function. The thermodynamic properties of the adsorbed water are also calculated and the results are compared with those of heavy water and discussed in view of the experimentally observed phenomena.

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Examination for Structural Safety of the Water Breaker to Green Water Impact Load (Green Water 충격하중을 받는 Water Breaker의 구조 안전성 검토)

  • Yang, Yun-Ho;Sim, Jong-Won;Yu, Byeong-Seok;Shin, Ki-Seok
    • Special Issue of the Society of Naval Architects of Korea
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    • 2006.09a
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    • pp.34-39
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    • 2006
  • In rough seas, water breaker of the sea-going ships is subject to high impact loads due to the green water and some ships' water breaker suffers structure damage. So, a substantial research on the structural response caused by green water impact is required. In this paper, the green water flow on bow deck is simulated by FDM(finite differential method). Using the results of green water simulation, impact loads on water breaker are calculated. Calculation results of the 6200TEU container ship's structural response to this green water impact pressure are shown and discussed for two condiered calculation conditions.

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IR Edge and Oxide Impurity Absorption in Heavy Metal Fluoride Glasses (플루오르화중금속 유리의 적외선에지 및 산화물(불수물) 흡수)

  • 정기호
    • Journal of the Korean Ceramic Society
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    • v.22 no.3
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    • pp.29-34
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    • 1985
  • The IR spectra of he heavy metal fluoride glasses showed peaks at $1, 400cm^{-1}$ or $1, 100cm^{-1}$ due to metal oxyfluoride impurities. The intensity of this band and hence the oxide impurity content of the glass could be reduced considerably by the use of reactive atmosphere melting under $CCl_4$ In comparison with the fundamental IR absorption band of heavy metal oxides the oxide impurity bands observed in the heavy metal fluoride glasses are multiphonon bands due to a 2-phonon absorption process. The envelope of the a vs. v curve beyond thue fundamental region shows the exponential fall off of a with increasing v-typical of intrinsic multiphonon absorption. In the multiphonon region the amount of structure is intermediate between that observed for covalent solids and that for ionic solids.

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Predicting the likelihood of impaired stream segments using Geographic Information System on Abandoned Mine Land in Gangwon Province

  • Lee, Ju-Young;Yang, Jung-Suk;Choi, Jae-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1081-1083
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    • 2007
  • The study in river basin has been performed for the identify water quality impaired stream segments, to create a priority ranking of those segments, and to calculate the heavy metal ion distribution for each impaired segment based on chemical and physical water quality standards. Two methods for modeling the potential area-specific heavy metal distribution are pursued in this study. First, a novel approach focuses on distance. Heavy metal distribution can be associated with a particular small geographic area. Based on the derived estimates an distribution map can be generated. Second, the approach is used the near watershed by means of kriging interpolation algorithm. These approaches provide an alternative distribution mapping of the area. The exposure estimates from both of these modeling methods are then compared with other environmental monitoring data. A GIS-based model will be used to mimic the hierarchical stream structure and processes found in natural watershed. Specifically, the relationship between landscape variables and reach scale habitat conditions most influential found in the Abandoned mine will be explored.

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