薄板铸机开浇冷齿形成的分析与解决

本钢炼钢厂薄板坯连铸机在开浇初期,特别是在低碳钢的生产时,结晶器内几乎每个浇次开浇时都会产生冷齿,由于薄板坯铸机拉速高,冷齿现象极易产生漏钢的事故,并产生7m左右的废坯,增加了生产成本。因此主要对能够引起冷齿的生产和设备各种相关的因素进行分析,并通过生产实践的方法找出最佳的解决办法。     

量子操作的分辨

利用量子操作的无错分辨来考虑量子操作的精确分辨,得到了量子操作精确分辨的充要条件;其次,将量子态的集合分辨推广到量子操作的集合分辨,同时得到了两个充要条件;最后考虑了量子操作无错分辨的失败概率的下界。     

复合床式低倍率循环流化床锅炉的研制开发

本文全面分析了较高循环倍率循环流化床锅炉所存在的技术问题,提出采用设计经验成熟、运行稳定可靠、热效率高、电耗低的低循环倍率循环流化床锅炉技术来实现循环流化床锅炉的大型化的新技术思想,并据此研制开发出复合床式低倍率循环流化床锅炉新技术。通过介绍和分析复合床式低倍率循环流化床锅炉的技术原理及技术特点,展示新炉型所具有的锅炉主要部件的灵活布置方式,为循环流化床锅炉的大型化指出了新的发展方向。     

基于床面形态的泥沙输移模式及其在黄河下游的应用

冲积河流系统中,水流在不规则床面上产生的漩涡对泥沙悬浮效率影响很大.基于漩涡流的运动特征及床面形态控制数m,本文研究了水流阻力与床面形态运动之间的关系.同时,在Bagnold泥沙悬浮效率(η_(sl))概念的基础上,提出了床沙质输沙能力公式,对其中的η_(sl)C_*进行了深入研究,建立的η_(sl)C_*与1/m的关系,能够反映床面形态由低能态到高能态区的发展过程.研究提出的输沙公式,经黄河下游调水调沙试验等实测资料验证表明,计算结果与实测值特别是相对平衡条件下的实测值吻合较好.在输沙能力公式研究中引入反映床面形态控制参数是一种新的尝试,该方法在研究中显示出较大的发展潜力.     

Multilevel modeling of self-esteem change during acute inpatient stroke rehabilitation.

Objective: To explore self-esteem change during inpatient stroke rehabilitation and moderators of change. Research Method: One hundred twenty survivors of stroke serially completed the State Self-Esteem Scale (SSES) during inpatient rehabilitation, as well as measures of mood and perceived recovery as potential moderators of change. Age, gender, prior stroke, prestroke depression, stroke laterality, and admission Functional Independence Measure (FIM) self-care, mobility, and cognitive scores were also included as moderators. Results: Multilevel modeling of the repeated administrations of the SSES indicated that self-esteem significantly improved during rehabilitation. Female gender, left hemisphere stroke, prior stroke, and lower admission FIM cognitive scores were associated with lower self-esteem ratings at admission, but only age and admission FIM self-care and mobility scores were associated with self-esteem change. Older individuals showed less self-esteem improvement than younger individuals, and higher self-care and mobility scores at admission were associated with greater self-esteem improvement. While mood change significantly covaried with self-esteem, the rate of mood change did not appear to influence rate of self-esteem change. Greater improvement in self-esteem over time was related to lower levels of perceived recovery, but this was likely because of the relationship between perceived recovery and self-esteem at rehabilitation admission. Implications: These results suggest that self-esteem improves during inpatient rehabilitation, and this change may be partially dependent on functional status. Implications for facilitating self-esteem change by the clinician are discussed, as well as future research directions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

华南海相下组合层序地层格架与油气勘探

在建立区域层序地层格架的基础上,指出区域性主力烃源岩及盖层主要形成于超层序的海侵体系域;高品质的区域性储层通常与超层序的高水位期-低水位期相一致。华南下组合海相碳酸盐岩油气纵向上总体存在3套生储盖组合,并将其划分为界面型、低位型、海侵型、高位型和综合型5种类型,不同类型的生储盖组合特征及成藏地质特征存在差异。提出礁滩相灰岩-白云化或白云岩-古岩溶为最有利储层,古隆起-后期构造圈闭为最有利部位,川东南-黔北地区为最有希望尽快取得突破的新区块的认识。     

降温热模拟实验中烃源岩成熟度和产气率的变化特征

对鄂尔多斯盆地低成熟(R₀=0.29%)、成熟(R₀=0.66%)和高成熟(R₀=1.71%)的3个煤样分别开展了降温、延长加热时间热模拟实验,研究烃源岩在降温时延长加热时间成熟度和产气率的变化特征。煤样在升温后降到一定的温度,延长加热时间烃源岩成熟度仍然发生变化,增加幅度为0.15%-0.40%。在同一温度不同时间段内,R₀值增加的速率存在差异,前期R。值增加速率较大.随着加热时间的延长R₀值增加的速率逐渐降低。降温延长加热时间测定的烃源岩产气率的变化特征是,早期产气率较低,随着加热时间的延长累积产气率逐渐增高。生气速率的变化特征如同R₀值,在前期生气速率较大,随加热时间延长生气率逐渐降低。实验结果表明,烃源岩在经历高温后降到一定的温度,延长加热时间可以继续生烃,只是生气速率逐渐减小。     

基于下装设计的人体建模

下体主要是由腰腹部、臀部、臀沟和腿部组成,提取了这些部位中与下装设计直接相关的18个部位的尺寸,定义了人体的主要特征切面,减少了人体平均形态的计算,同时尽可能地保留了人体躯干的三维体形信息。通过对这些部位特征形状的提取和分析,将控制服装款式变化的关键部位的变化转换为形值点参数的变化,进而进行曲面的拟合,建立了基于下装特征的参数化人体模型。结果可用于指导下装的定制开发。     

一种级联简单奇偶校验码的调制编码设计

研究级联简单奇偶校验 (SPC) 码与QAM调制的联合优化。通过分析加QAM调制后的级联SPC码的近似联合界,发现增加携带奇偶校验位符号的欧式距离,并相应地降低携带信息位符号的欧式距离,能够使总体上达到更优化的分配。然后通过计算这个近似联合界得到最优的奇偶校验位和信息位之间的欧式距离分配。仿真结果表明对于某些码联合优化后比原先不联合优化在高信噪比时有2dB的性能提高。     

基于等分圆弧滑面土质边坡 的稳定性极限分析方法

基于等分圆弧滑面的简化条件,采用土塑性极限分析理论,建立了土质边坡极限分析模型,并推导得到了 土质边坡稳定系数计算公式。该方法考虑了圆弧滑面的内能耗散率作用和边坡土体自重荷载、地震惯性力及孔 隙水压力所做的外功率作用,可以解决土质边坡稳定性分析问题,是一种改进的土质边坡稳定性评价极限分析 方法。