Global Mapper在水库库容计算及淤积分析中的应用研究

基于快捷精准计算水库库容,并与原始库容对比分析库容淤积的目的,使用Global Mapper软件的库容计算和DEM叠加分析功能,通过水库库容复核工程实例进行应用试验,结果表明使用Global Mapper计算库容的结果精度与等高线法的库容结果相当,计算高效、结果可靠,DEM叠加分析成果可以直观展示库容淤积分布,有助于为管理单位冲淤冲沙提供决策。

Lateral load-carrying capacity analyses of composite shear walls with double steel plates and filled concrete with binding bars

A method is developed to predict the lateral load-carrying capacity of composite shear walls with double steel plates and filled concrete with binding bars(SCBs). Nonlinear finite element models of SCBs were established by using the finite element tool, Abaqus. Tie constraints were used to connect the binding bars and the steel plates. Surface-to-surface contact provided by the Abaqus was used to simulate the interaction between the steel plate and the core concrete. The established models could predict the lateral load-carrying capacity of SCBs with a reasonable degree of accuracy. A calculation method was developed by superposition principle to predict the lateral load-carrying capacity of SCBs for the engineering application. The concrete confined by steel plates and binding bars is under multi-axial compression; therefore, its shear strength was calculated by using the Guo-Wang concrete failure criterion. The shear strength of the steel plates of SCBs was calculated by using the von Mises yielding criterion without considering buckling. Results of the developed method are in good agreement with the testing and finite element results.

Shape design of the reinforcement for bending load-carrying capacity of under-matched butt joint under four-point bending load

To improve the bending load-carrying capacity （ BLCC） of under-matched butt joint under four-point bending load in the elastic stage, the shape design of the reinforcement is studied based on the theoretics of mechanics of materials. The concept, criterion, realization condition and design proposal of equal bending load-carrying capacity （EBLCC） are put forward. The theoretical analysis results have been verified by the finite element method. The simulation results are coincident basically with the ones of theoretical analysis. The research results show that the shape design of the reinforcement of EBLCC can improve BLCC of under-matched butt joint and the unilateral-side type reinforcement can replace double-side symmetry

Using a GIS to Assessment the Load-Carrying Capacity of Soil Case of Berhoum Area, Hodna Basin, (Eastern Algeria)

The concept of load-carrying capacity of the soil can be evaluated by two main components: permissible stress and permissible depth;and therefore, running it begins its assessment that allows an outline of exploitation. Nevertheless, the assessment of the load-carrying capacity made the object of several works of research and many models, based on the multi-criteria analysis, have been established. This work examines the contribution of GIS approach to assessment load-carrying capacity of the soil. This one has been finished in two practicums: 1) Assessment of the capacity of soil by a multi-criteria approach, using the Weighted Sum Model (WSM);2) It brought to use the GIS approach to evaluate and spatialize degree of soil bearing stresses resulting from the buildings, as well as load distribution. The method has been applied to the Berhoum area of Hodna Basin, in eastern Algeria, where each is characterized by its various natural properties and density of equipment. Final results are better in the classification of the degree of load-carrying capacity possible in each site. This results in allowing exploiters to program their optimal designs for the rational management of the area.

Boundary slippage for generating hydrodynamic load-carrying capacity

Boundary slippage is used to generate the load-carrying capacity of the hydrodynamic contact between two parallel plane surfaces. In the fluid inlet zone, the fluidcontact interfacial shear strength on a stationary surface is set at low to generate boundary slippage there, while in the fluid outlet zone the fluid-contact interfacial shear strength on the stationary surface is set at high enough to prevent the occurrence of boundary slippage. The fluid-contact interfacial shear strength on the entire moving surface is set at high enough to prevent boundary slippage on the moving surface. These hydrodynamic contact configurations are analyzed to generate the pronounced load-carrying capacity. The optimum ratio of the outlet zone width to the inlet zone width for the maximum load-carrying capacity of the whole contact is found to be 0.5.

A Discusion on Limited Load-Carrying Capacity of Rectangular Plates

The elastic-plastic method is often used in designing the inner flat bulkhead plates of submarines, and the upper structure of ships and drilling platforms. Such bulkhead plates can bear the load only once. For the improvement of the load-carrying capacity or the reduction of the weight of plates, the yield line analytical method is employed in this paper to design the bulkhead plate to improve economy and increase the effiective load. Besides, a further sutdy of this method has been made theoretically and experimentally, and the data of the limited load-carrying capacity of the plate have been obtained. Furthermore, the safety coefficients for such a method are presented, which can be used as reference for related departments and staffs.

Qualitative Considerations on the Influence of the Gases Water Vapor and Carbon Dioxide on the Global Environmental Temperature from the Point of View of Textbook Knowledge

The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional energy input or prolongation of the interaction time solar radiation—Earth matter. The contribution of H2O(g) and CO2 to the protection of the earth against excessive warming is experimentally and by basic laws of nature secured. For a greenhouse effect, a part of the earth radiation must be radiated back to the earth and then into space. If one understands the earth radiation as radiation of a black body with the average global environmental temperature, from all vibrations normal modes of the gases H2O(g) and CO2 only the bending mode of CO2 with 4% of the solar constant can contribute beside the rotational modes of the water to the greenhouse effect. The contributions of the normal modes of H2O(g) and CO2 to the heat capacity of the atmosphere are negligible. Therefore, in agreement with studies by K. Ångström, CO2 contributes only to the stabilization of the global environmental temperature. Whether the use of renewable energies can actually at least mitigate the increase of the environmental temperature is by no means certain but must be examined for each individual case. With certainty, this goal can only be achieved by reducing the energy consumption of mankind.

能源转型及“双碳”目标背景下全球炼油行业发展新态势与前景展望

2023年,全球炼化项目建设稳步推进,炼油重心继续东移;全球新增炼油能力8617.5万吨/年,高于上年新增量,总炼油能力提升至51.8亿吨/年。全球原油加工量合计约8240万桶/日,恢复至疫情前水平,装置开工率持续回升,炼油毛利继续保持历史较高水平。炼油行业加快结构调整和转型升级,欧美炼油商加快投资生物燃料生产,中东非洲地区以新建项目推动炼油业转型升级。炼油技术在劣质重油加工、清洁燃料生产、炼油向化工转型等方面取得持续进展,原油直接制化学品技术成为重点方向。2024年全球有望新增炼油能力近1亿吨,全球炼化项目在2030年前仍将继续保持增长,增长中心集中在亚太和中东地区;2024年全球炼厂原油加工量同比增长约100万桶/日,增量主要来自中国、中东、非洲地区,世界炼油毛利有望维持较好水平;2030年前炼油结构调整和转型升级仍是炼油业发展的主基调,新兴经济体炼油行业将继续加快转型升级和绿色智能化发展进程。

证据驱动的循证决策国际进展、趋势与展望

起源于上世纪90年中期英国政府的循证实践,近年来在全球战略规划制定、国际学术交流、国际合作网络搭建、跨部门协作等方面涌现出诸多新进展,推动了循证决策的快速发展。上述新进展显示出循证决策已成为全球治理和政策制定的共同愿景、循证决策制度化成为全球共同追求的治理创新、证据流动系统成为循证决策的基础遵循、多元化证据产品贯穿于循证决策全过程等发展趋势。随着循证决策助推国际战略规划制定更加科学和有效,证据获取体系、证据评估系统、多样化证据产品将得到快速发展,政府决策者的循证决策能力将得到快速提升。

钢筋混凝土结构整体承载能力、可靠度和整体抗力系数校准--以简支梁为例

目前,基于构件承载能力极限状态的荷载抗力系数设计法或分项系数法是世界各国土木工程结构设计规范所主要采用的概率极限状态设计方法,目前这两种方法存在两个基本矛盾,需要发展基于结构整体可靠度的整体安全系数设计方法。总结钢筋混凝土结构整体承载力设计值和整体抗力系数的确定方法,将FIB混凝土结构整体抗力系数设计法与结构整体可靠度理论相结合,提出钢筋混凝土结构整体承载能力可靠度和整体抗力系数的校准原理。以双面配筋钢筋混凝土结构简支梁为例,通过非线性有限元分析和蒙特卡洛模拟,校准得到钢筋混凝土简支梁的整体承载能力可靠度和整体抗力系数,研究发现钢筋混凝土简支梁的整体承载力可靠指标总体大于构件承载力可靠指标,且整体可靠度指标和构件可靠度指标均远大于目标可靠度指标,表明《建筑结构可靠性设计统一标准》(GB 50058—2018)的目标可靠度指标有较大提升空间。

锁定脆弱国家:撒哈拉以南非洲的安全供给与能力建设困境

由于国家安全机制的缺位或无效,撒哈拉以南非洲地区的安全供给出现地方化、社会化、商业化和外部化趋势。该地区国家内部的非国家行为体和来自外部的跨国行为体在不同的条件下组合,形成了碎片化、多种安全主体互补又竞争的“多元混杂”的安全供给格局,这与单一中心、自上而下的安全供给格局明显不同。在这种供给格局中,很难明确区分“国家和非国家”“正式和非正式”“现代和传统”,它们重叠交织在一起。安全供给的地方化、社会化、商业化和外部化使这一地区国家的安全能力被限制,整个国家的安全建设陷入困境,从而导致其“脆弱国家”的地位被“锁定”。由于国家化的动力不足,该地区安全供给的“多元混杂”格局短期内很难改变。作为全球“安全洼地”,中国与这一地区的安全合作空间巨大,因此可以从理念创新和实际操作两方面推动全球安全倡议的实践。

基于构建新发展格局的首都发展战略

新中国成立以来,首都发展战略演变在根本上取决于中国社会主要矛盾、中心任务和发展战略的转化。在揭示形成新发展格局本质为构建强大的全球资源优化配置能力的基础上,提出新发展阶段首都发展战略本质就是建设强大的全球资源优化配置中心城市,走全球高精尖集聚发展之路,全主体、全要素、全过程提升首都在全球范围内决定“为谁生产、生产什么、怎样生产、在哪里生产、谁以及按什么规则和程序决策”的能力。为此,要吸引和培育跨国公司总部、全球性组织、有全球话语权的媒体机构,加快建设全球金融中心、全球科技创新中心、全球人才发展中心、国际消费中心城市和新兴要素交易市场,大力发展国际规则创制能力、全球定价能力、高端生产性服务业、全球城市服务能力和世界顶级交通体系。

全球价值链嵌入对企业不同类型技术创新的影响研究

基于“双循环”视角和实现创新驱动的经济高质量发展目标,研究了企业在全球价值链(GVC)上游嵌入度和全球价值链(GVC)下游嵌入度对企业国内外不同类型技术创新的影响效应和机制,包括国内技术创新和国外技术创新。研究发现:GVC上游嵌入度显著促进了国内技术创新,对外资企业、一般贸易企业和高行业竞争度企业的影响更明显,而GVC上游嵌入度对国外技术创新没有产生显著的促进效应;GVC下游嵌入度则对企业国内外技术创新均产生抑制效应,对内资企业、一般贸易企业和低竞争程度企业的作用尤其明显。机制检验表明,吸收能力有助于增强GVC上游嵌入度对国内创新的促进效应,同时弱化GVC下游环节嵌入对企业国内外技术创新的阻碍作用。进一步分析发现,GVC上游嵌入度对绿色技术创新的促进效应和GVC下游嵌入度的绿色技术创新抑制效应,仅在非污染行业中存在。研究结论为我国在全球价值链嵌入过程中,促进企业技术创新能力提升以及实现产业升级提供了重要的政策参考。

A novel efficient energy absorber with free inversion of a metal foam-filled circular tube

In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone.

大学出版社国际传播现状与能力建设策略探究

大学出版社是我国出版行业国际传播力量的组成部分,肩负着传承和传播文化的使命。大学出版板块在推进中国文化域外传播、提升中国学术国际影响力上开创了“有为、有位”的良好局面,但仍存在着一些大学出版社国际传播能力较弱的问题。大学出版社需要发挥优势制定有效策略,快速提升国际传播能力,如依靠母体大学培育国际化产品、利用高校特点培育国际化人才、利用母校国际化优势获得国际传播契机、通过与海内外优质学术出版机构的合作借势蓄能、利用国家资助项目快速步入国际化轨道等,同时要以传统出版和数字出版融合发展模式构建“走出去”的多元格局,拓展“走出去”新路径。

Q460高强钢简支梁整体稳定极限弯矩计算式研究

为揭示《钢结构设计标准》(GB 50017—2017)、《高强钢结构设计标准》(JGJ/T 483—2020)中Q460高强钢梁整体稳定设计方法的差异,提出精确的Q460高强钢梁整体稳定极限弯矩计算式,通过梳理现有文献,提出了钢梁整体稳定极限弯矩的指数形式的一般计算式;根据GB 50017—2017的规定,提出了其稳定系数的统一计算式及对应的“稳定系数-正则化长细比”曲线表达式;提出了理想受弯构件的“稳定系数-正则化长细比”曲线表达式。对比了GB 50017—2017和JGJ/T 483—2020的“稳定系数-正则化长细比”曲线,归纳了其特点,并分析了现有钢梁整体稳定的指数形式极限弯矩计算式存在的问题。基于GB 50017—2017的基准弯矩,提出了Q460高强钢梁整体稳定极限弯矩的指数形式计算式,解决了JGJ/T 483—2020无法直接确定正则化长细比的问题,并采用14个双轴对称、单轴对称工字形截面简支梁的试验数据验证了本文建议公式的精度。研究表明,对于Q460/Q460GJ高强钢简支梁整体稳定的极限弯矩,本文建议的指数形式计算式较现行标准GB 50017—2017、JGJ/T 483—2020中的计算式具有更高的精度。

全球城市创新评价指数对北京建设国际科技创新中心的启示

全球城市科技创新能力评价是世界各研究机构的研究热点。分析比较全球城市创新评价指数可深化对国际科技创新中心形成与演化逻辑的认识,以及量化刻度全球城市创新发展格局。以8套知名全球城市创新评价指数为对象,重点分析其评价目的、评价方法、评价指标、评价结果等内容的科学性和合理性。同时,动态跟踪北京与纽约、波士顿、伦敦、东京等国际科技创新中心排名变化情况。研究结果表明,当前全球城市创新格局较为稳定,北京在科学论文和创业生态等指标上的得分处于全球领先地位,但人才和大学等指标仍是其得分短板,需要进一步建设高水平人才队伍,打造高效率开放创新生态。

2023年聚丙烯市场回顾与2024年展望

2023年,我国引领全球聚丙烯(PP)产业大幅扩能,产能增量占全球增量的68%。全球及我国PP消费平稳,南亚及东南亚地区PP消费增速较快,我国消费增量高于全球1个百分点。但由于我国上游产能增量巨大,导致下游价格下降,利润降低。预计2024年,东北亚地区PP产能大幅扩张,我国仍处于投产高峰期,其中丙烷脱氢(PDH)装置是扩能的主要路线。在后疫情时代,全球PP贸易增长,我国经济平稳向好,贸易规模向常态化回归。我国PP市场下游需求向好,消费逐渐恢复,主要体现在房地产、汽车、家电和包装等方面。

基于3d Max的水库库容计算

水库库容是水利工程建设和运营管理中不可忽略的重要参数之一,引入3d Max软件,对比传统库容计算方法与地理信息处理软件ArcGIS、Global Mapper进行库容计算,旨在摆脱传统数据分析与公式计算,保证精确性的同时,直观地展示水库水位变化过程。结果表明:3d Max能够精确地进行库容计算,且对水库各水位淹没地势情况进行直观展示,可为施工建设提供有效参考。

WHO监管评估体系概况及对我国药品监管国际化的思考

为应对全球复杂监管环境带来的挑战,推动医疗产品全球化监管协同,世界卫生组织(WHO)制定了一套统一的全球基准评估工具(GBT),并在此基础上发布WHO列名监管机构(WLAs)清单,为监管机构获得全球认可提供透明且基于证据的途径。长久以来,我国高度关注与WHO的交流合作,在疫苗监管和全球化领域已取得了丰硕的成果。在药品监管领域,我国已重塑了整个药品监管生态系统,具备了独立审查创新产品的能力,但在国际社会尚未形成普遍认知。本文从GBT和WLAs清单关注的监管透明度建设角度出发,探索分析我国药品监管体系面临的挑战,并提出改进建议,以期助力我国更加深入地融入全球监管协同、监管信赖的国际大趋势中。