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| 1 | Numerical study of hydrodynamic mechanism of dynamic tidal power显示文摘Dynamic tidal power is a new way of capturing tidal energy by building a water head using a dike perpendicular to the coast. This study explored the hydrodynamic mechanism of the water head across an intended dynamic tidal power dike system using the Delft3 D-FLOW software module. The propagating wave was simulated in a rectangular domain with a horizontal sea bottom at a 30-m depth. A significant water head was created across the dike by blocking the water. The water head increased with increasing dike length and increasing undisturbed tidal current acceleration. The maximum water head for the dike with a length of 50 km, located 900 km from the western boundary, was 2.15 m,which exceeded the undisturbed tidal range. The time series of the water head behaved in a manner identical to the undisturbed tidal current acceleration. The distribution of the water head over the dike assumed an elliptical shape. A parasitic wave was generated at the attachment and scattered outward. The phase lag across the dike did not behave as a linear function of the detour distance. | Peng Dai Ji-sheng Zhang Jin-hai Zheng Kees Hulsbergen Gijs van Banning Jeroen Adema Zi-xuan Tang | 2018 | Water Science and Engineering2018，11，3： | 5 |
| 2 | The Structure of A Turbulent Jet in A Crossflow-Effect of Jet-Crossflow Velocity显示文摘A comprehensive numerical study on the three-dimensional structure of a turbulent jet in crossflow is performed. Thejet-to-crossflow velocity ratio (R) varies in the range of 2 ~ 16; both vertical jets and inclined jets without excess streamwisemomentum are considered. The numerical results of the standard two-equation k-~ model show that the turbulent structurecan be broadly categorised according to the jet-to-crossflow velocity ratio. For strong to moderate jet discharges, i.e. R >4, the jet is characterized by a longitudinal transition through a bent-over phase during which the jet becomes almost parallelwith the main freestream, to a sectional vortex-pair flow with double concentration maxima; the computed flow details andscalar mixing characteristics can be described by self-similar relations beyond a dimensionless distance of around 20 ~ 60.The similarity coefficients are only weakly dependent on R. The cross-section scalar field is kidney-shaped and bifurcated,with distinct double concentration maxima; the aspect ratio is found to be around 1.2. A loss in vertical momentum is ob-served and the added mass coefficient of the jet motion is found to be approximately 1. On the other hand, for weak jets instrong crossflow, i.e. R≤ 2, the lee of the jet is characterized by a negative pressure region. Although the double vortexflow can still be noted, the scalar field becomes more symmetrical and no longer bifurcated. The similarity coeffcients are al-so noticeably different. The predicted jet flow characteristics and mixing rates are well supported by experimental and field | 李行伟 匡翠萍 陈国谦 | 2002 | China Ocean Engineering2002，17，1： | 5 |
| 3 | Measurement and research method of metallogenic depths of Jiaojia orefield and Linglong orefield, Shandong Province, China显示文摘Taking the contribution of the tectonic force to the total hydrostatic pressure into account, the author puts forward a new method on the calculation of the depth of petrogenesis and metallogenesis which is summarized as follows: first the tectonic added hydrostatic pressured Ps is subtracted from the total hydrostatic pressure P, then using their difference Pr, according to the general method the depth of petrogenesis and metallogenesis can be determined in consideration of lateral constraint.By the new method the following data on the depths of the metallogenesis are obtained: 2 243.6 m (No. I and No. II veins with metallogenic epoch of 105 Ma) and 1 632.38 m (No. III vein with 105 Ma) for Jiaojia orefield, and 3 454.97 m (NE-trending zone with 213.2 Ma), 1 902.79 m (ENE-trending zone with 100.28 Ma), 1 090.97 m (NE-trending zone with 80.67 Ma) and 720.55 m (NNE-trending zone with 71.86 Ma) for Linglong orefield. | 吕古贤 | 1997 | Science China Earth Sciences1997，40，5： | 4 |
| 4 | Numerical studies of the hydrodynamic damping of a vibrating hydrofoil in torsional mode显示文摘The vortex-induced vibration may lead to a premature failure of hydraulic mechanical systems,especially under the resonance condition in the torsional mode.To predict the structural fatigue life,a careful consideration of the dynamic response to the hydraulic excitations is essential in the design phase.This study focuses on the numerical investigation of the relationship between the flow velocity,the added mass and the hydrodynamic damping,particularly,with respect to a Donaldson-type hydrofoil,vibrating in the first torsional mode.A two-way fluid-structure interaction(FSI)method is used to predict above two parameters.The flow velocity is in the range of 0 m/s-20m/s.To evaluate the hydrodynamic damping ratio,an identification method is proposed,based on a modified version of the logarithmic decay method.The relative deviations of the simulated natural frequencies and hydrodynamic damping ratios as compared with the experimental data for the first torsional modes,are within 8.1%and 16.6%,respectively.The analysis results show that the added mass coefficient for the first torsional mode is in the range of 1.59-1.86,and is around 44%of that for the first bending mode.The trends of the boundary layer thickness and the wake width against the reduced velocity are found to be opposite to that of the hydrodynamic damping ratio.The theoretical equation for predicting the hydrodynamic damping ratio is modified,which is shown to be more reliable due to its consideration of the velocity independent hydrodynamic damping phase. | Yong-shun Zeng Zhi-feng Yao Biao Huang Fu-jun Wang Qin Wu Ruo-fu Xiao Guo-yu Wang | 2021 | Journal of Hydrodynamics2021，33，2： | 4 |
| 5 | Study on Hydrodynamic Coefficients of Double Submerged Inclined Plates显示文摘Added mass and damping coefficients are very important in hydrodynamic analysis of naval structures. In this paper,a double submerged inclined plates with ‘/\' configuration is firstly considered. By use of the boundary element method(BEM) based on Green function with the wave term, the radiation problem of this special type structure is investigated. The added mass and damping coefficients due to different plate lengths and inclined angles are obtained. The results show that: the added mass and damping coefficients for sway are the largest. Heave is the most sensitive mode to inclined angles. The wave frequencies of the maximal added mass and damping coefficients for sway and roll are the same. | WANG Ke ZHANG Zhi-qiang | 2018 | China Ocean Engineering2018，32，1： | 3 |
| 6 | Effect of nitrogen levels on photosynthetic parameters,morphological and chemical characters of saplings and trees in a temperate forest显示文摘Exploring the response differences of leaf physiology parameters to enhanced nitrogen deposition between saplings and trees is vital for predicting the variations of terrestrial ecosystem structure and function under future global climate change. In this study, the ecophysiological parameters of saplings and trees of Fraxinus mandshurica Rupr. were measured at different levels of nitrogen addition in a temperate forest. The results show that ecophysiological parameters maximum net photosynthetic rate(P_(max)), apparent quantum efficiency(a), dark respiration(R_d), light saturation point(L_(sp)), photosynthetic nitrogen use efficiency(PNUE),specific leaf area(SLA)and stomatal conductance under saturated light intensity(G_(smax)) were higher in saplings than in trees. These physiological parameters and not N_(leaf)(leaf nitrogen content)led to relatively lower P_(max) and R_d in trees. For both saplings and trees, low and median nitrogen addition(23 and 46 kg ha^(-1)a^(-1)) resulted in significant increases in Pmax, Rd, Lsp, Chl, PNUE, SLA and Gsmax. These parameters tended to decline under high additions of nitrogen(69 kg ha^(-1)a^(-1)),whereas Nleaf was always enhanced with increasing nitrogen. Variations in Pmax and Rd with increasing nitrogen were attributed to variations in the strongly related parameters of, Lsp, Chl, PNUE, SLA and Gsmax. Overall, the response sensitivity of physiological parameters to enhanced nitrogen levels was lower in trees compared with saplings. | Jinwei Sun Fuqi Yao Jiabing Wu Pingcang Zhang Wensheng Xu | 2018 | Journal of Forestry Research2018，29，6： | 3 |
| 7 | The Innovation Research of Financial Early-Warning Index Measurement显示文摘The period economic fluctuation is vital for an enterprise to exist and further develop,it directly affect the enterprise financial health.So,it is significant to build up financial early\|warning index and measure the warning condition that the enterprise faces and take the effective measures to eliminate. We criticize Altman’s Z calculating model and build up some new indexes for enterprise financial early\|warning condition measuring and making sound decision. | Zhang You-tang Cheng Jun-ning Liang Wei-jun | 2002 | Wuhan University Journal of Natural Sciences2002，7，3： | 3 |
| 8 | Recent Near-surface Temperature Trends in the Antarctic Peninsula from Observed,Reanalysis and Regional Climate Model Data显示文摘This study investigates the recent near-surface temperature trends over the Antarctic Peninsula.We make use of available surface observations,ECMWF’s ERA5 and its predecessor ERA-Interim,as well as numerical simulations,allowing us to contrast different data sources.We use hindcast simulations performed with Polar-WRF over the Antarctic Peninsula on a nested domain configuration at 45 km(PWRF-45)and 15 km(PWRF-15)spatial resolutions for the period 1991?2015.In addition,we include hindcast simulations of KNMI-RACMO21P obtained from the CORDEX-Antarctica domain(~50 km)for further comparisons.Results show that there is a marked windward warming trend except during summer.This windward warming trend is particularly notable in the autumn season and likely to be associated with the recent deepening of the Amundsen/Bellingshausen Sea low and warm advection towards the Antarctic Peninsula.On the other hand,an overall summer cooling is characterized by the strengthening of the Weddell Sea low as well as an anticyclonic trend over the Amundsen Sea accompanied by northward winds.The persistent cooling trend observed at the Larsen Ice Shelf station is not captured by ERA-Interim,whereas hindcast simulations indicate that there is a clear pattern of windward warming and leeward cooling.Furthermore,larger temporal correlations and lower differences exhibited by PWRF-15 illustrate the existence of the added value in the higher spatial resolution simulation. | Deniz BOZKURT David HBROMWICH Jorge CARRASCO Keith MHINES Juan Carlos MAUREIRA and Roberto RONDANELLI | 2020 | Advances in Atmospheric Sciences2020，37，5： | 3 |
| 9 | Added Resistance Acting on Hull of a Non Ballast Water Ship显示文摘In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp<0.6, are assumed. | Ngo Van He Yoshiho Ikeda | 2014 | Journal of Marine Science and Application2014，13，1： | 2 |
| 10 | 采用基于雷诺平均的N-S方程和势流方法进行散货船阻力和运动的预报研究(英文)显示文摘Resistance prediction of ships using computational fluid dynamics has gained popularity over the years because of its high accuracy and low cost. This paper conducts numerical estimations of the ship resistance and motion of a Japan bulk carrier model using SHIP_Motion, a Reynolds-averaged Navier–Stokes (RaNS)-based solver, and HydroSTAR, a commercial potential flow (PF)-based solver. The RaNS solver uses an overset-structured mesh and discretizes the flow field using the finite volume method, while the PF-based solver applies the three-dimensional panel method. In the calm water test, the total drag coefficient, sinkage, and trim were predicted using the RaNS solver following mesh dependency analysis, and the results were compared with the available experimental data. Next, calm water resistance was investigated for a range of Froude numbers. The added resistance in short-wave cases was simulated using both RaNS and PF solvers, and the results were compared. The PF solver showed better agreement with the RaNS solver for predicting motion responses than for predicting added resistance. While the added resistance results could not be directly validated because of the absence of experimental data, considering the previous accuracy of the RaNS solver in added resistance prediction and general added resistance profile of similar hull forms (bulk carriers), the prediction results could be concluded to be reliable. | Hafizul Islam Mashiur Rahaman M.Rafiqul Islam Hiromichi Akimoto | 2019 | Journal of Marine Science and Application2019，18，3： | 1 |
| 11 | Numerical Investigation on Submerged Horizontal Plate显示文摘 | Kang Haigui(康海贵) Wang Ke(王科) | 2001 | Marine Science Bulletin2001，3，2： | 1 |
| 12 | Correction显示文摘The manuscript has been republished with updated references of previous experimental studies.These references have been added in order to further reflect the confirmation and scientificity of the results.References have been added as follows. | Xinquan Zhao Liang Zhao Tianwei Xu Shixiao Xu | 2020 | Ecosystem Health and Sustainability2020，6，1： | 1 |
| 13 | Calculation of the Added Mass of a Liquid Tank's Bulkheads显示文摘The added mass coefficient and the water level index formulas for the same-phase and anti-phase vibration of rectangular liquid tanks' bulkheads were derived based on dry mode theory. Three fluid-structure interaction numerical methods including Fluid FEM and Fluid BEM were used in this case. The comparison of numerical and theoretical results by the present method shows that ANSYS/Fluid80 is more credible, the NASTRAN/Virtual Mass Method is more suitable for engineering calculations and results of the same-phase vibration by the present method is more accurate. | Junkai Zhu Zhe Lin Qiang Liu Lihua Zhang | 2014 | Journal of Marine Science and Application2014，13，1： | 1 |
| 14 | Hydroelastic dynamic characteristics of a slender axis-symmetric body显示文摘The slender axis-symmetric submarine body moving in the vertical plane is the object of our investigation.A coupling model is developed where displacements of a solid body as a Euler beam(consisting of rigid motions and elastic deformations) and fluid pressures are employed as basic independent variables,including the interaction between hydrodynamic forces and structure dynamic forces.Firstly the hydrodynamic forces,depending on and conversely influencing body motions,are taken into account as the governing equations.The expressions of fluid pressure are derived based on the potential theory.The characteristics of fluid pressure,including its components,distribution and effect on structure dynamics,are analyzed.Then the coupling model is solved numerically by means of a finite element method(FEM).This avoids the complicacy,combining CFD(fluid) and FEM(structure),of direct numerical simulation,and allows the body with a non-strict ideal shape so as to be more suitable for practical engineering.An illustrative example is given in which the hydroelastic dynamic characteristics,natural frequencies and modes of a submarine body are analyzed and compared with experimental results.Satisfactory agreement is observed and the model presented in this paper is shown to be valid. | CHEN WeiMin 1,LI Min 2*,ZHENG ZhongQin 1 & ZHANG LiWu 1 1 Laboratory of Environmental Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China 2 School of Aeronautics Sciences and Technology,Beijing University of Aeronautics and Astronautics,Beijing 100191,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，7： | 1 |
| 15 | Wave Analysis of Porous Geometry with Linear Resistance Law显示文摘The wave diffraction-radiation problem of a porous geometry of arbitrary shape located in the free surface of a fluid is formulated by a set of integral equations, assuming a linear resistance law at the geometry. The linear forces, the energy relation and the mean horizontal drift force are evaluated for non-porous and porous geometries. A geometry of large porosity has an almost vanishing added mass. The exciting forces are a factor of 5–20 smaller compared to a solid geometry. In the long wave regime, the porous geometry significantly enhances both the damping and the mean drift force, where the latter grows linearly with the wavenumber. The calculated mean drift force on a porous hemisphere and a vertical truncated cylinder, relevant to the construction of fish cages, is compared to available published results. | JORgen Dokken John Grue Lars Petter Karstensen | 2017 | Journal of Marine Science and Application2017，16，4： | 0 |
| 16 | 试论如何搞好SMT代工一的作业成本管控显示文摘随着电子产品组装利润的每况愈下,表面组装SMT(SurfaceMountedTechnology)代工行业已稍然步入微利时代,而微利时代更需要精细化的成本管理与控制。在提升企业竞争力的诸多要素中,其中成本控制是最基本的也是最关键的因素,尤其是生产作业的成本管理ABCM(Activity—BasedCostingManagement)。SMT的作业(Activity),是指为组装PCBA所必需的各个工作程序或工作环节,而作业成本就是因此而发生的间接或直接费用的统称。作业成本管理(ABcM),是以作业站别作为分摊成本的基础,在SMT工厂管理上可运用在报价决策、业务订单管理、工厂及产能规划、产品品质管理、顾客关系管理乃至企业策略上,它可以为决策者提供即时有效的精确资讯,它是一种通过对所有作业活动进行追踪的动态反映,并对作业绩效和资源利用情况的综合成本计算和管理方法。在SMT代工厂如何进行生产作业成本的管控呢?最基本的方法就是树立以现场“作业”为核心的管理思想,把成本管理及计算深入到作业层面,通过对作业方法的具体分析与成本的精细化计量管理,将产品成本做到最省从而增加企业及工厂的效益。那么,我们该如何搞好作业成本的管控呢?笔者有以下具体措施。首先,须搞清楚SMT工厂作业成本的基本构成及特点,只有获得清晰的作业成本构成(CostComposition),才能有的放矢地实施生产作业成本的管控。其二,利用IE作业手法,搞好作除团队中的懈怠和浪费等不良因素,搞好团队协作实现最佳效益。为了实施SMT作业成本管控,须搞好生产作业链(ActivityChain)优化与价值链(ValueStreamMapping)分析,掌握作业成本基本法则实现作业成本管理与控制。而降低成本(Costdown)需要从大处着眼小处着手,具体实施时须本着专业的态度,注重细节从点滴做起。 | 杨根林 | 2012 | 现代表面贴装资讯2012，，3： | 0 |
| 17 | Myocardial perfusion imaging in patients with a recent, normal exercise test显示文摘AIM: To investigate the added value of myocardial perfusion scintigraphy imaging (MPI) in consecutive patients with suspected coronary artery disease (CAD) and a recent, normal exercise electrocardiography (ECG). METHODS: This study was a retrospective analysis of consecutive patients referred for MPI during a 2-year period from 2006-2007 at one clinic. All eligible patients were suspected of suffering from CAD, and had performed a satisfactory bicycle exercise test (i.e. , peak heart rate > 85% of the expected, age-predicted maximum) within 6 mo of referral, their exercise ECG was had no signs of ischemia, there was no exercise-limiting angina, and no cardiac events occurred between the exercise test and referral. The patients subsequently underwent a standard 2-d, stress-rest exercise MPI. Ischemia was defined based on visual scoring supported by quantitative segmental analysis (i.e. , sum of stress score > 3). The results of cardiac catheterizationwere analyzed, and clinical follow up was performed by review of electronic medical files. RESULTS: A total of 56 patients fulfilled the eligibility criteria. Most patients had a low or intermediate ATPⅢ pretest risk of CAD (6 patients had a high pre-test risk). The referral exercise test showed a mean Duke score of 5 (range: 2 to 11), which translated to a low postexercise risk in 66% and intermediate risk in 34%. A total of seven patients were reported with ischemia by MPI. Three of these patients had high ATPⅢ pre-test risk scores. Six of these seven patients underwent cardiac catheterization, which showed significant stenosis in one patient with a high pre-test risk of CAD, and indeterminate lesions in three patients (two of whom had high pre-test risk scores). With MPI as a gate keeper for catheterization, no significant, epicardial stenosis was observed in any of the 50 patients (0%, 95% confidence interval 0.0 to 7.1) with low to intermediate pre-test risk of CAD and a negative exercise test. No cardiac events occurred in any patients within a median follow up period of > 1200 d. CONCLUSION: The added diagnostic value of MPI in patients with low or intermediate risk of CAD and a recent, normal exercise test is marginal. | Ann Bovin Ib C Klausen Lars J Petersen | 2013 | World Journal of Cardiology2013，5，3： | 0 |
| 18 | Numerical Experiment on Two-Dimensional Line Thermal显示文摘The time evolution of a two-dimensional line thermal-a turbulent flow produced by an initial element with signifi-cant buoyancy released in a large water body, is numerically studied with the two-equation k - s model for turbulenceclosure. The numerical results show that the thermal is characterized by a vortex pair flow and a kidney shaped concentra-tion structure with double peak maxima; the computed flow details and scalar mixing characteristics can be described byself-similar relations beyond a dimensionless time around 10. There are two regions in the flow field of a line thermal: amixing region where the concentration of tracer fluid is high and the flow is turbulent and rotational with a pair of vortexeyes, and an ambient region where the concentration is zero and the flow is potential and well-described by a model ofdoublet with strength very close to those given by early experimental and analytical studies. The added virtual mass coeffi-cient of the thermal motion is found to be approximately 1. The aspect ratio for the kidney-shaped sectional thermal isfound to be around 1.45 for the self-similar phase. The predicted thermal spreading and mixing rate compares well withexperimental data. | J.H.W.LEE 陈国谦 | 2002 | China Ocean Engineering2002，17，4： | 0 |
| 19 | Myths and realities of China's apparel industry——from a global value chain perspective显示文摘Rising export and market shares and rampant bankruptcies coexist in China's apparel industry.Against the backdrop of the global value chain,the by-country industrial competitiveness evaluation system based on final products is failing.Using the global value chain theory,this article investigates the international competitiveness of China's apparel industry and introduces the case study of Nike's global value chain,reaching the conclusion that existing evaluations have exaggerated the international competitiveness of China's apparel industry.China's apparel industry is at the lowest level of the global value chain,and most local enterprises have not entered the mainstream global value chain and are still internationally uncompetitive.As far as China's current economic development level and targets are concerned,it may be too unrealistic to discuss industrial upgrading entirely from the perspective of OEM-ODM-OBM.China's apparel producers should stick to both paths:one is the priority to strengthen manufacturing and OEM;the other is to do more learning to go beyond sub-contract manufacturing and prepare for long-term growth of OBM.Building middle and high-end apparel producers and creating local brands by virtue of China's status as a big country is the right path for development given the industry's present situation. | 谭力文 马海燕 刘林青 | 2009 | China Economist2009，4，2： | 0 |
| 20 | Studies on permissible levels of breathing resistance for aircraft oxygen equipment(Review)显示文摘Studiesonpermissiblelevelsofbreathingresistanceforaircraftoxygenequipment(Review)￥MaRuishan(马瑞山)(DepartmentofAerospacePhysiol... | 马瑞山 | 1994 | Journal of Medical Colleges of PLA(China)1994，9，2： | 0 |
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