A Review of Beach Bye-Law Usage in Supporting Coastal Management in Ireland

Coastal areas are commonly the focus of a range of human activities and uses. Beaches are one example of multi-use coastal environments, accommodating activities linked to leisure and recreation, amenity, conservation and business, often simultaneously. Ireland is no different in this regard, as its beach resources provide a range of goods and services of societal value. Ireland has 16 coastal counties and their associated local authorities have a beach management remit, a role that can present a number of challenges. The use of beach bye-laws is one option to support management of beach environments by local authorities. Local authority personnel tasked with beach management from each coastal local authority were surveyed to assess the actual and potential role of beach bye-laws in contributing to more effective management of beach environments and to broader coastal management. Usage of beach bye-laws varied across local authority areas and evidence suggested that the efficacy, use, and implementation of beach bye-laws differed from county to county. Beach bye-laws offer potential but interaction with other initiatives as part of a wider program for coastal management may yield improved results.     

Comparing Fisher Interviews,Logbooks, and Catch Landings Estimates of Extraction Rates in a Small-Scale Fishery

Researchers are turning to alternative data sources (e.g., resource user knowledge) to provide information required for wildlife management. Little is known about the reliability of data elicited from resource users relative to data obtained from user-independent approaches (e.g., observations of fish catches). We test for consensus among three methods that quantify past (1996 to 2007) seahorse catch-per-unit-effort (CPUE) for a small-scale, data-poor fishery in the Philippines: interviews with fishers about good, bad, and typical catch; fisher logbooks; and observations of catch landings. Interviews and logbooks indicated no trends in CPUE through time, consistent with results from the fisher-independent metric, catch landings. Although interview estimates of “typical” CPUE greatly exceeded “typical” observed catches and logbook estimates, interview estimates of “bad” CPUE were comparable. Catch landings estimates for a fisher in a particular year were uncorrelated to what he reported during retrospective interviews. Interviews should be used cautiously to inform specific catch targets (e.g., total allowable catches), although including interview questions about a range of catch experiences (e.g., good, bad and typical), may improve interview-derived data. Logbooks are particularly useful for capturing information about fishing expeditions that produce no fish, which are largely missed by other methods.     

含起重设备的船舶上层建筑吊装强度有限元分析

为准确计算船舶上层建筑吊装强度,采用MSC.Patran和MSC Nastran软件对175 000 t散货船上层建筑吊装建立整体结构有限元模型。采用含起重设备的有限元分析法计算上层建筑在吊装过程中的结构响应,并与直接约束法和惯性释放法进行对比分析,比较3种有限元分析法计算得到的应力、变形和吊点支反力情况,分析含起重设备的有限元分析法的准确性。结果表明,含起重设备的有限元分析法可对结构的应力、变形和吊点支反力进行较为准确的计算,优于直接约束法和惯性释放法。含起重设备的有限元分析法对船舶上层建筑吊装强度和吊装方案的评估具有一定的工程价值。     

中国企业海外重化工投资项目配套码头选址原则

中国企业的大型海外重化工投资项目通常需要自建码头以完成物料运输,因此项目的选址很大程度取决于码头的建设位置。分析归纳此类项目码头选址具有空间跨度大、明确约束少、研究深度深等特征,筛选影响该类项目码头选址的主要因素有波浪条件、水深条件、泥沙条件、地质地震情况、陆域场地条件、港口依托条件、运输里程等,提出以建设成本和运营成本总和最低为评判标准的选址准则目标,总结从初选的宏观研究到终选的方案微观研究的选址思路和流程,并以中国企业在马来西亚的某投资项目为例,演绎整个选址的过程,可供类似项目选址参考。     

船闸浮式系船柱升级改造设计与应用

随着船舶大型化的推进,部分船闸无法较好地满足过闸船舶安全系缆。以株洲一线船闸为例,在浮式系船柱井槽不变的前提下,对浮式系船柱进行升级改造设计。通过改变浮式系船柱结构形式,优化系缆高度、浮筒直径以及吃水深度等关键参数,将系缆力提升至100 kN,双层系缆高度分别提高至1 900和3 700 mm。经过有限元计算分析验证,系船架结构的强度、刚度均满足要求。工程实践表明：改造后的浮式系船柱边界参数与井槽尺寸匹配合理,投产后运行可靠,船舶过闸系缆解缆效果良好,可为类似船闸工程浮式系船柱的升级改造设计提供参考。     

双碳目标背景下商用车能源与动力系统技术进展

为探明“双碳”目标背景下商用车能源与动力系统技术进展,通过查阅相关文献以及行业调研,系统梳理商用车能源与动力系统技术研究现状,详细总结传统商用车、纯电动商用车、混合动力商用车、氢燃料电池商用车的能源与动力系统技术的发展进程,归纳分析能源与动力系统技术的发展方向,以及商用车行业短期发展趋势。从用车能效、能源互动及全生命周期减碳的视角,为“双碳”目标背景下的商用车能源与动力系统技术发展路径提供建议。     

电气化背景下电动汽车热管理技术的进步与展望

电动汽车热管理已成为保障车辆宽温域环境适应能力、电池热安全和乘员舱热舒适性等方面的关键技术,同时也对电动汽车的能耗,特别是高低温环境下的整车能耗有着显著影响。随着车辆电气化和智能化的快速发展,与传统汽车相比,电动汽车热管理技术和发展路线在动力系统、空调系统等子热力系统和整车层面都呈现出了明显的差异和巨大的进步。综述了国内外电动汽车热管理技术领域重要的研究进展,阐述了电池、电机、热泵空调等子系统和整车集成热管理系统的技术进步,总结了当前电动汽车热管理亟待突破的技术重点和未来发展趋势。     

Numerical study on flow-induced noise for a steam stop-valve using large eddy simulation

The noise induced by the fluctuant saturated steam flow under 250 °C in a stop-valve was numerically studied.The simulation was carried out using computational fluid dynamics（CFD） and ACTRAN.The acoustic field was investigated with Lighthill＇s acoustic analogy based on the properties of the flow field obtained using a large-eddy simulation that employs the LES-WALE dynamic model as the sub-grid-scale model.Firstly,the validation of mesh was well conducted,illustrating that two million elements were sufficient in this situation.Secondly,the treatment of the steam was deliberated,and conclusions indicate that when predicting the flow-induced noise of the stop-valve,the steam can be treated as incompressible gas at a low inlet velocity.Thirdly,the flow-induced noises under different inlet velocities were compared.The findings reveal it has remarkable influence on the flow-induced noises.Lastly,whether or not the heat preservation of the wall has influence on the noise was taken into account.The results show that heat preservation of the wall had little influence.     

四轮转向电动汽车车架的设计与有限元分析

现有电动汽车底盘普遍为在传统汽车的基础上进行的改进,不能很好的适应电动汽车特有的结构,为更好的实现四轮转向的功能,重新设计了适合四轮转向电动汽车的车架。应用三维软件SolidWorks,通过整车虚拟装配确定了合理的四轮转向电动汽车的车架结构,进而建立了车架的三维模型。运用有限元分析理论,将模型导入Ansys Workbench软件后,建立了车架的有限元模型,对车架在弯曲和扭转工况下的静态结构性能进行了分析,得出相应工况下的应力和应变大小;还进行了模态分析,避免了共振。在满足强度和刚度的条件下对车架结构进行了改进,并通过焊接加工得到了适合四轮转向电动汽车的车架,对以后电动汽车底盘的改进设计提供了参考。     

高铁夕发朝至列车开行与天窗设置协同优化

高速铁路夕发朝至列车开行与天窗设置存在动态影响关系,将两者进行协同优化有助于满足旅客夜间出行需求,提升铁路运力资源配置.?以通道型高速铁路为对象,在分析高速铁路夕发朝至列车与天窗设置影响关系的基础上,以高速铁路夕发朝至列车总的旅行时间最少和高速铁路夕发朝至列车的开行对既有列车运行图的影响最小为目标,建立了列车开行模式未...