以技术进步促进蒸汽能源的节约

本文运用“软科学”一即通过建立数学模型，进行系统分析和系统优化，阐述对蒸汽管网优化运行的方法及原理，达到提高供热效率及节能降耗的目的．     

在τ—ρ域用特征积分法反演层状介质的速度和密度

本文提出一种在τ-p 域内用特征积分法反演层状介质速度与密度的方法。该方法首先把有偏移距的地震资料变换到截取时间τ和水平慢度 P 域内,然后,对任取的二道平面波地震记录,分别用特征积分法反演波阻抗,再用这对波阻抗分离层状介质的速度和密度。文中讨论了误差对反演结果的影响,并对理论模型进行了试算,效果令人满意。     

微波等离子体化学气相沉积的 a-Si∶H 性能研究

本文着重对微波等离子体化学气相沉积法高速沉积的 a-Si∶H 膜的物理性能进行评价研究.测量了沉积膜的光电性能、暗电导激活能、光禁带宽度、光吸收特性、沉积膜中悬键态密度以及氢含量等,并讨论沉积条件对膜性能的影响.结果表明,在沉积速率高达30～90(?)/s 情况下,膜的光电导(光照强度10~5Lux)与暗电导比值可达10~3～10~5,暗电导率从10~(-3)到10~(-11)((?)cm)~(-1),其激活能在0.23～0.88eV 之间(0～200℃温度范围内),光禁带宽度为1.40～2.20eV,氢含量约为2～20%.     

Improved coupled-mode theory for nonlinear directional couplers

An improved coupled-mode equation for nonlinear directional couplers (NLDC) with Kerr-like nonlinear media is proposed. The method is based on the generalized reciprocity relation in which two sets of field solutions satisfying Maxwell's equations are for the NLDC and for the isolated nonlinear waveguide. That leads to a reasonable result that all the coefficients in the coupled-mode equations, including the coupling coefficient, become power dependent. For the NLDC with a self-focusing or self-defocusing nonlinear material, the authors examine how the coupling coefficient, the coupling length, and the guided power depend on the input power in the range of coupling stronger than in previous reports. It is found that the critical power at which the coupling length becomes infinity does not increase as much with the two guides for the case of self-focusing media     

The Hardness of the Closest Vector Problem With Preprocessing Over$ell_infty$Norm

We show that the closest vector problem with preprocessing (CVPP) over lscr _infin norm (CVPP_infin) is NP-hard. The result is obtained by the reduction from the subset sum problem with preprocessing to CVPP_infin. The reduction also shows the NP-hardness of CVP_infin, which is much simpler than all previously known proofs. In addition, we also give a direct reduction from exact 3-sets cover problem to CVPP_infin     

Material removal and surface damage in EDM of Ti3SiC2 ceramic

Material removal and surface damage of Ti₃SiC₂ ceramic during electrical discharge machining (EDM) were investigated. Melting and decomposition were found to be the main material removal mechanisms during the machining process. Material removal rate was enhanced acceleratively with increasing discharge current, i_e, working voltage, u_i, but increased deceleratively with pulse duration, t_e. Microcracks in the surface and loose grains in the subsurface resulted from thermal shock were confirmed, and the surface damage in Ti₃SiC₂ ceramic led to a degradation of both strength and reliability.     

昆2井优快钻井及油气层保护技术

昆2井是一口位于柴北缘西段的昆特依凹陷潜伏Ⅰ号圈闭上的风险探井,设计井深为5950m。针对柴北缘深探井存在的主要技术难题,制定了昆2井的技术对策。通过对钻井设备的优选、井身结构的优化、钻头及钻具组合的优选、钻井参数及钻井液性能的优化、油气层保护技术的研究与应用,形成了一套适合于柴北缘的优快钻井技术,使昆2井的完钻井深达到5950m。与邻区的深探井平均水平相比,在井深增加888m、大尺寸井眼段更长的前提下,昆2井的钻井、完井周期分别缩短了98.75d、124.2d,钻机月速度增加了317m/台,平均机械钻速增加了0.82m/h。根据“理想充填新理论”,确定了保护油气层的最优复配暂堵方案,利用该方案所配制的钻井液其渗透率恢复值达到了87.5%以上,流变性能良好,滤失量低,对改善泥饼质量、增强井壁稳定性有明显的效果。     

2#板坯连铸机振动台故障分析及改造

论述了银山型钢有限公司炼钢厂2#板坯连铸机自投产以来其振动台存在的问题，根据实际情况分析论证并进行改造实施，实施后效果明显。     

小红楼

小红楼建于1921年，是一座三层的法式小洋楼。三十年代，它被英国百代唱片公司收购，抗日战争期间，一度被日本人占有，解放后，它成为中国唱片公司的所在地，伟大的中国国歌就诞生在这里。     

En/Decoder for Spectral Phase-Coded OCDMA System Based on Amplitude Sampled FBG

A novel en/decoder for spectral phase-coded optical code-division multiple-access system based on amplitude sampled fiber Bragg grating (FBG) is proposed. Both equivalent chirp and equivalent phase shift are achieved by amplitude sampling. Compared with previous en/decoder based on step chirped FBG, it is easier to fabricate. The performance of the proposed en/decoder is verified by both numerical simulation and experimental demonstration.