摘要：In future high-capacity wavelength division multiplexed(WDM)optical networks,the failure of a network component such as a fiber link can lead to severe disruption in the networks’***,it is imperatively important to provide fast and full protection in WDM optical *** this paper,we propose a new approach,called shared preconfigured protection cycles(shared-p-cycles),for the design of survivable WDM *** develop an integer linear program(ILP)formulation to solve the problem of shared-p-cycles design for WDM networks with and without wavelength *** results show that the shared-p-cycles design is more efficient in the use of spare capacity and requires much less spare capacity than the conventional pcycles design.

摘要：为了研究巨厚表土-孤岛煤柱组合结构致冲机理,以山东某煤矿1305工作面冲击地压事故为工程背景,采用数值模拟、理论分析、现场实测等方法,系统进行巨厚表土-孤岛煤柱组合结构的空间结构、失稳判据、冲击机制等研究。研究结果表明:通过数值模拟证实土压力拱的存在,说明土压力拱传递的巨厚表土自重为1305工作面整体失稳冲击的主要力源。通过研究巨厚表土采场推采荷载传递机制,建立组合结构工程力学模型,设计地层传递载荷估算方法,提出巨厚土拱-孤岛煤柱结构失稳冲击工程判据。揭示巨厚土拱-孤岛煤柱结构失稳冲击机理:厚表土采场顺序接续形成土压力拱结构,导致临侧孤立煤体承载高水平的支承压力,当孤岛煤柱承载的叠加应力满足动力失稳临界阈值时,土拱-煤柱结构发生整体组合失稳冲击。研究结果可为巨厚表土条件下的冲击地压防治提供参考。

摘要：为探究不同品种和添加剂对燕麦青贮品质的影响,本试验选取“白燕11”“黑玫克”和“凯撒”3个品种的燕麦作为试验对象,设计4种添加剂处理,即空白对照(CK)、植物乳杆菌(LP,接种量为1×10^(5) CFU/g FW)、布氏乳杆菌(LB,接种量为1×10^(5) CFU/g FW)和苯甲酸钠(SB,添加量为1.5%FW),在青贮45 d后,对燕麦青贮饲料的发酵品质、营养品质和康奈尔净碳水化合物-蛋白质体系(CNCPS)组分进行分析。结果显示:1)与“白燕11”燕麦青贮饲料相比,“黑玫克”燕麦青贮饲料的pH显著降低(P<0.05),乙酸(AA)含量显著提高(P<0.05);与CK相比,添加LP、LB和SB均显著降低了燕麦青贮饲料的pH和氨态氮(NH 3-N)含量(P<0.05),显著增加了乳酸(LA)含量(P<0.05),并且以LB的表现最为突出。2)在品种方面,“黑玫克”燕麦青贮饲料的干物质(DM)含量最低,“凯撒”燕麦青贮饲料的DM和可溶性碳水化合物(WSC)最高,其粗蛋白质(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)和酸性洗涤木质素(ADL)含量显著低于其他品种(P<0.05);在添加剂方面,与CK相比,添加LP、LB和SB均显著降低了燕麦青贮饲料的NDF和ADF含量(P<0.05)。3)在品种方面,“黑玫克”燕麦青贮饲料CNCPS的蛋白质组分中非蛋白氮(PA)含量较低,快速降解蛋白质(PB1)、慢速降解蛋白质(PB3)含量较高,结合蛋白质(PC)含量显著低于其他品种(P<0.05);在添加剂方面,与CK相比,添加LP、LB和SB均显著提高了燕麦青贮饲料CNCPS的蛋白质组分中PB1和中速降解蛋白质(PB2)含量(P<0.05),显著降低了PA和PC含量(P<0.05),并且以LB的表现最为突出。4)“黑玫克”燕麦青贮饲料的碳水化合物(CHO)含量最高,“凯撒”燕麦青贮饲料的非结构性碳水化合物(NSC)和糖类(CA)含量显著高于其他品种(P<0.05),其可利用纤维(CB2)和不可利用纤维(CC)含量显著低于其他品种(P<0.05);与CK相比,添加LP、LB和SB均显著提高了燕麦青贮饲料的CA、淀粉和果胶(CB1)含量(P<0.05),显著降低了CB2和CC含量(P<0.05),并且以LB的表现最为突出。综上所述,添加LB有利于提高燕麦青贮饲料品质,青贮发酵后品质较好的燕麦品种为“黑玫克”,且“黑玫克”燕麦青贮饲料的蛋白质组分最优,“凯撒”燕麦青贮饲料的碳水化合物组分最优。因此,“黑玫克”是适用于三江源地区调制青贮的优质燕麦品种。

摘要：按一定配比将混凝土与抗蚀防渗剂搅拌均匀后置于模具中,脱模试件在湿度为95%、温度为20℃下养护28 d后取出,测定其抗压强度。然后再研究28 d试件在磷氟环境酸性废水中完全浸泡下的耐侵蚀性能。结果表明,相对于空白对照组,采用42.5水泥(C40)的混凝土与抗蚀防渗剂混合所得试件浸泡在酸性废水中180 d后进行抗压强度及失重率测试,结果均优于对照组试样。

摘要：由于在航空航天和核工业中存在超高温工况,结构对材料耐高温、耐腐蚀、高强度性能提出了较高要求,此外较低的材料密度也是提升结构轻量化水平的重要性能。碳化硅陶瓷基复合材料因具有低密度、耐高温、高强度等特点,已经在相关领域表现出较大的潜力,并且已有较成熟的工程应用。本文以SiCf/SiC复合材料(碳化硅作为陶瓷基体,SiC纤维作为增强体)为对象,简要论述了国内外相关研究人员对碳化硅陶瓷基复合材料制备加工工艺的研究,根据其各向异性、非均质性以及双模量等特征,结合具体实例进行分析,建立了一种基于ANSYS ACP技术的复合材料设计分析方法,初步形成针对耐高温结构复合材料建模和仿真优化分析的解决方案。

摘要：The hydraulic characteristics of artificial waterfalls constitute an important research area for both academia and industry. As yet, the hydraulic parameters used in the hydraulic design of landscape waterfalls are not well understood for use in qualitative and quantitative analyses. Due to their complicated shapes and appearances, it remains a challenging problem to design or simulate realistic waterfall scenes. In this paper, we present a hybrid model and an efficient numerical method for simulating the hydraulic characteristics of waterfalls and investigate the critical flow in waterfall design and the adherent flow phenomenon. We fit empirical equations to predict the size and shape of different waterfall flow patterns to provide a basis for the design and construction of waterscapes in the real world. We then apply our work to an artificial waterfall in Kraal Jiang River and the results demonstrate that our model achieves desirable control qualities and good agreement in a real-world application. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

摘要：分布式多层系统由客户端应用程序、应用服务器层、数据库服务器层构成。由于分布式多层应用系统均在网络环境下运行,所以,它的执行效率成为设计时不可忽视的重点。以提高分布式多层应用系统的执行效率为目的,文中总结了如何使用Delphi所提供的相关技术来提高分布式多层MIS系统执行效率的几种方法。并得出结论:合理地运用Delphi所提供的相关技术可以大幅度提高分布式多层应用系统的执行效率。

摘要：商用车前下防护在乘用车与商用车发生正面碰撞时起防钻碰作用,文章根据目前市场对前下防护轻量化要求,参照GB 26511法规要求,利用Hyper Mesh软件对某商用车型前下防护建立碰撞有限元模型,通过Radioss求解器进行模拟计算,优化结构。提高了设计效率降低了实验成本,并提高实物样件碰撞实验评估的通过率,文章对工程实践具有指导意义。

摘要：One judiciously designed strategy of utilizing an ultrathin but conductive Ga_(2)O_(3):Si nanolayer to prepare(AlGa)_(2)O_(3)crystalline film is *** from the existence of Ga_(2)O_(3):Si nanolayer,a high-quality(Al_(0.68)Ga_(0.32))_(2)O_(3)sesquioxide film with 68 at.%aluminum was epitaxially grown on sapphire substrates,which was characterized by high-resolution transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray *** bandgap was broadened to 6.14 eV,and a vacuum ultraviolet(VUV)(AlGa)_(2)O_(3)/Ga_(2)O_(3):Si photodetector was subsequently *** detector exhibits a pretty high on-off ratio of about 10^(3),an open-circuit voltage of 1.0 V and a responsivity of 8.1 mA W^(-1) at 0 V bias *** performances imply that the proposed strategy is valuable for improving the quality and also adjusting the bandgap of(AlGa)_(2)O_(3)sesquioxides,which is expected to facilitate their application in VUV photodetection.

摘要：Clearly understanding the structure-function relationship and rational design of efficient CO2 electrocatalysts are still the *** article describes the molecular origin of high selectivity of formic acid on N-doped SnO2 nanoparticles,which obtained via thermal treatment of g-C3N4 and SnCl2·2H2O *** with density functional theory(DFT)calculations,we discover that N-doping effectively introduces oxygen vacancies and increases the charge density of Sn sites,which plays a positive role in CO2 *** addition,N-doping further regulates the adsorption energy of^*OCHO,^*COOH,^*H and promotes HCOOH *** from above modulation,the obtained N-doped SnO2 catalysts with oxygen vacancies(Ov-N-SnO2)exhibit faradaic efficiency of 93% for C1 formation,88% for HCOOH production and well-suppression of H2 evolution over a wide range of potentials.