摘要：A multi-body wave energy converter,consisting of three floats and modeled as a two body problem,is optimised to enhance its mean absorbed power using the Response Surface Optimisation *** optimisation focuses on two input parameters namely;the floats’diameters and the spacing,in various sea states and at different PTO dampings.A frequency domain analysis is performed for the WEC model scaled at 1∶50 in regular and irregular *** results are validated against numerical and experimental data available in the *** show good agreement against the unmoored model’s added mass,radiation damping,response amplitude operator,mean absorbed power and,capture width *** sea states selected for optimisation are represented by a JONSWAP wave spectrum with,a range of significant wave heights(0.04 to 0.06 m)and a range of peak periods(0.8 to 1.3 s).This corresponds to(2 to 3 m)significant wave heights and(5.6 to 9.2 s)peak periods in full *** show that the optimised WEC model demonstrates good and consistent enhancement of its mean absorbed power and capture width ratio.

摘要：Improving rollover and stability of the vehicles is the indispensable part of automotive research to prevent vehicle rollover and *** main objective of this work is to develop active control mechanism based on fuzzy logic controller(FLC) and linear quadratic regulator(LQR) for improving vehicle path following,roll and handling performances simultaneously.3-DOF vehicle model including yaw rate,lateral velocity(lateral dynamic) and roll angle(roll dynamic) were *** controller produces optimal moment to increase stability and roll margin of vehicle by receiving the steering angle as an input and vehicle variables as a feedback *** effectiveness of proposed controller and vehicle model were evaluated during fishhook and single lane-change *** results demonstrate that in both cases(FLC and LQR controllers) by reducing roll angle,lateral acceleration and side slip angles remain under 0.6g and 4° during maneuver,which ensures vehicle stability and handling ***,the sensitivity and robustness analysis of developed controller for varying longitudinal speeds were investigated.

摘要：过渡金属磷化物是电催化设计中的新兴材料,而多元金属磷化物因其能显著提高电催化活性而备受关注.然而,由于不同种类金属前驱物之间水解和缩合速率的差异,当前有关超过两种金属元素和化学计量比精确控制的多元金属磷化物的报道非常少.因此,合理设计多元金属磷化物的组成对提高其催化性能具有重要意义.本工作通过直接磷化二价过渡金属离子氢氧化物的合成策略,制备了能够精确控制化学计量比(x:y:z=(1–10):(1–10):1)的分级结构Co_(x)Ni_(y)Fe_(z)P,其中具有最优组分的Co_(1.3)Ni_(0.5)Fe_(0.2)P在析氧反应(OER)中展示了优异的催化活性和高稳定性.密度泛函理论计算表明,相对于其他组分的过渡金属磷化物,Co_(1.3)Ni_(0.5)Fe_(0.2)P在费米能级附近的态密度明显增加,这可以增强催化剂对OH−的吸附,从而提升OER性能.

摘要：优化分析和计算液体动力学(CFD ) 同时被使用了，在哪个一个参量的模型在发现最佳的答案起一个重要作用。然而，与不规则的曲线为复杂形状创造一个参量的模型是困难的，例如一种海底的壳形式。在这研究，立方的 Bezier 曲线和曲线飞机交叉方法被用来产生考虑三个输入参数的一种参量的海底的壳形式的一个稳固的模型：鼻子半径，尾巴半径，和长度高度壳比率(L/H ) 。应用程序接口(API ) 脚本也被用来在 ANSYS 设计 modeler 写代码。结果证明海底的形状能与输入参数的某变化被产生。一个例子被给那显示出建议方法怎么能成功地被用于一个壳抵抗优化盒子。中间的海底的类型的参量的设计被选择被修改。首先，预先，原来的海底的模型用 CFD 被分析。然后，使用反应表面图，某候选人有一个最小的壳抵抗系数的最佳的图案被获得。进一步，在目标驱动的优化(GDO ) 的优化方法被实现与最小的壳抵抗系数发现海底的壳形式(C t ) 。最小的 C t 被获得。在在起始的潜水艇和最佳潜水艇之间的 C t 价值的计算差别在 0.26% 附近，与起始的潜水艇和是的最佳潜水艇的 C t 0.001 508 26 和 0.001 504 29 分别地。结果证明最佳潜水艇壳形式显示出更高的鼻子半径(r n ) 和更高的 L/H 起始的潜水艇比那些塑造，当时尾巴的半径(r t ) 比起始的形状的小。

摘要：Resistance analysis is an important analytical method used to evaluate the hydrodynamic performance of High Speed Craft (HSC). Analysis of multihull resistance in shallow water is essential to the performance evaluation of any type of HSC. Ships operating in shallow water experience increases in resistance because of changes in pressure distribution and wave pattern. In this paper, the shallow water performance of an HSC design concept, the semi-Small Waterplane Area Twin Hull (semi-SWATH) form, is studied. The hull is installed with fin stabilizers to reduce dynamic motion effects, and the resistance components of the hull, hull trim condition, and maximum wave amplitude around the hull are determined via calm water resistance tests in shallow water. These criteria are important in analyzing semi-SWATH resistance in shallow water and its relation to flow around hull. The fore fin angle is fixed to zero degrees, while the aft fin angle is varied to 0o, 5o, 10o, and 15o. For each configuration, investigations are conducted with depth Froude numbers (FrH) ranging from 0.65 to 1.2, and the resistance tests are performed in shallow water at the towing tank of UTM. Analysis results indicate that the resistance, wave pattern, and trim of the semi-SWATH hull form are affected by the fin angle. The resistance is amplified whereas the trim and sinkage are reduced as the fin angle increases. Increases in fin angle contribute to seakeeping and stability but affect the hull resistance of HSCs.

摘要：The high pressure waves generated due to muzzle blast flow of tank gun during firing is a critical issue to examine. The impulsive noise from the gun has various negative effects such as damage of human bodies, damage of structures, creating an environmental, social problem and also military problems such as exposure of location of troops. This high pressure impulsive sound, generated during the blast flow, was studied and attenuated. An axisymmetric computational domain was constructed by employing Spalart Allmaras turbulence model. Approximately 90% of pressure and 20 dB of sound level are reduced due to the use of the three baffle silencer at the muzzle end of the gun barrel, in comparison with the tank gun without silencer. Also, the sound pressure level at different points in the ambient region shows the same attenuation in results. This study will be helpful to understand the blast wave characteristics and also to get a good idea to design silencer for large caliber weapon system.

摘要：在过去的十五年里，轮船安全处理的注意开始通过整个海上的工业作为一个目的而非限制扫了。基于风险的轮船设计(RBD ) 方法论，在常规设计过程以内倡导风险评价的系统的集成开始了到起飞。尽管有这宽识别和增加的流行，能潜在地破坏结果的质量的重要因素在风险评价过程期间来自量、质的方面。这份报纸由通过与数据通过第一原则的途径产生了相结合的历史的数据的有效存储并且处理为风险评价开发形式化的方法论详细说明一个有希望的解决方案。这个方法应该帮助在能在设计舞台为决策被采用的选择站台(贝叶斯的网络) 产生适当风险模型。

摘要：层状双金属氢氧化物(LDHs)作为一种类水滑石薄膜,以其优异的特性在许多领域中具有广泛的应用.然而,现有的LDH膜制备路线具有大规模生长受限和不可控等问题.本文中,我们受一种草本植物“落地生根”(Bryophyllum Pinnatum)具有肆意生长特性的启发,首次引入可牺牲的共溅射锌-铝中间层作为“植物种子”,通过“局部溶解”和“溶液渗透”的结构转化机制在任意形状、大小及材质的基底材料上实现大规模、厚度可控的LDH膜制备.通过调控中间膜的成分、结构和表面形貌,设计具有不同特性的LDH转化膜.实验结果表明,所制备的LDH膜具有较大的厚度和多级微观结构的特性,在严苛的磨损条件下仍能实现良好的机械稳定性.另外,我们设计了一系列基于锌-铝单金属中间层的电偶模拟实验对LDH膜的化学转化机理进行了深入探究,解决了传统复杂水热过程中实时监测困难的问题.本工作不仅开发了一种制备具有多尺度特性的LDH转化膜的新策略,同时揭示了复杂的LDH原位转化机理,为拓宽LDH材料在先进智能材料上的实际应用提供了新的发展思路.

摘要：Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3 4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3 4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3 h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12 h was needed. A small amount of solvent（3 ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.

摘要：The main configuration of ship construction consists of standard and fabricated stiffening members,such as T-sections,which are commonly used in *** the welding process,the nonuniform heating and rapid cooling lead to welding imperfections such as out-of-plane distortion and residual *** to these imperfections,the fabricated structural members may not attain their design load,and removing these imperfections will require extra *** present work investigated controlling these imperfections at both the design and fabrication stages.A typical fabricated T-girder was selected to investigate the problem of these imperfections using double-sided welding.A numerical simulation based on finite element modeling(FEM) was used to investigate the effects of geometrical properties and welding sequence on the magnitude of the welding imperfections of the *** FEM results were validated with the experimental measurements of a double-sided fillet *** the design stage,the optimum geometry of the fabricated T-girder was determined based on the minimum steel weight and out-of-plane ***,regarding the fabrication stage,a parametric study with two variables(geometrical properties and welding sequence)was conducted to determine the optimum geometry and welding sequence based on the minimum welding out-of-plane *** the flange thickness and reducing the breadth while keeping the T-girder section modulus constant reduced the T-girder weight and out-of-plane *** welding produced a significant reduction in the out-of-plane distortion,while an insignificant increase in the compressive residual stress occurred.