在VB程序中自动配置ODBC数据源的方法

简要介绍了微软ODBC数据库访问接口和利用VB语言在软件设 计中通过ADO数据访问对象、RDO数据访问对象及Windows系统注册表操作技术,实现程序自 动注册用户ODBC数据源的方法,解决了在数据管理软件安装过程中通过手动依次配置系统OD BC数据源的问题,同时也就在VB程序中如何在Windows系统注册表中建立自己的用户信息键 与键值的设置与读取作了实例讲解。     

A reactive GRASP and path relinking for a combined production–distribution problem

An NP-hard production–distribution problem for one product over a multi-period horizon is investigated. The aim is to minimize total cost taking production setups, inventory levels and distribution into account. An integer linear model is proposed as a compact problem specification but it cannot be solved to optimality for large instances. Instead of using a classical two-phase approach (production planning and then route construction for each day), metaheuristics that simultaneously tackle production and routing decisions are developed: a GRASP (greedy randomized adaptive search procedure) and two improved versions using either a reactive mechanism or a path-relinking process. These algorithms are evaluated on 90 randomly generated instances with 50, 100 and 200 customers and 20 periods. The results confirm the interest of integrating production and distribution decisions, compared to classical two-phase methods. Moreover, reaction and path-relinking give better results than the GRASP alone.     

Correlation of phenolic acid content of maize to resistance toSitophilus zeamais,the maize weevil,in CIMMYT'S collections

The (E)-ferulic acid content of the grain of nine populations of land races of maize derived from CIMMYT's collections was found to be negatively correlated to susceptibility characteristics towards the maize weevilSitophilus zeamais. Correlation coefficients for six susceptibility parameters and (E)-ferulic acid content were significant and ranged from –0.58 to –0.79. A multiple regression analysis by the SAS forward procedure using the primary seed characteristics associated with susceptibility indicated that the ferulic acid content was the only significant factor in explaining variation in at least two susceptibility parameters: the Dobie index and adult preference. In 15 CIMMYT pools, correlations between four susceptibility parameters and (E)-ferulic acid content were also significant (–0.76 to –0.81). The results suggest that phenolic acid content is a leading indicator of grain resistance or susceptibility to insects and may represent a newly identified mechanism of resistance.     

使用磁化率仪检测混凝土构件中钢筋的分布状况试验研究

建筑物预埋钢筋的检测一直是控制施工质量的重要检测内容,尝试将磁法勘探常用的SM30磁化率仪应用到混凝土构件中钢筋的分布状况检测中。通过建立实验模型,对建筑工程中常用的不同直径、不同埋深的钢筋进行测量,确定钢筋中心投影位置,探索可检测深度,定性测定磁化率随钢筋直径的变化,通过对混凝土建筑楼板和素混凝土地面进行实地检测,试验证明SM30磁化率仪用于建筑工程常用钢筋无损检测是有效的可行的。     

抗滑桩设计参数的敏感性分析

利用自编程序ASP1.0,对滑坡的物理力学参数、桩截面型式及截面尺寸等对桩的锚深、内力、配筋量的影响进行了定量计算分析,结果表明:滑床土的内摩擦角φ对桩锚深、内力和配筋量的影响较大,桩锚深、内力和配筋量对φ变化很敏感;桩锚深、内力和配筋量对滑床土粘聚力c的变化相对不敏感;桩锚深对地基系数m的变化相对不敏感,而内力及配筋量则受m影响较大;滑坡的推力对桩的锚深、内力及配筋量影响显著,近似成线性关系,当过大的锚深导致施工困难时,单靠增大桩宽的方法来减小锚深是不经济的,而应通过调整桩距、削坡、改变桩截面等综合措施予以实现;同一滑坡条件下,空心抗滑桩一般是最经济的桩型.     

Dielectric properties, ac conductivity and thermal behaviour of flux grown cadmium titanate crystals

The dependence of loss tangent (tan δ) and both real and imaginary parts of the dielectric constant (′ and ″) on temperature in the range 298–923 K and frequency in the range 10³–10⁶ Hz for flux grown CdTiO₃ single crystals is reported. The ln σ_ac versus T plots suggest the conduction mechanism to be ionic hopping conduction. From ln σ_ac versus frequency curves, it can be seen that the slope decreases with the rise in temperature, suggesting that the ionic hopping conduction diminishes with the rise in temperature. The activation energy at various fixed frequencies is calculated from the slope of the graph between ln σ_ac versus 1/T (×10³ K⁻¹). Thermal behaviour of flux grown CdTiO₃ crystals using thermoanalytical techniques including TG, DTA and DTG is discussed. Thermal analysis suggests decomposition of CdTiO₃ in the temperature interval of 1386–1693 K leading to the formation of TiO₂ as the final product. Results obtained on application of TG based models viz. Horowitz–Metzger, Coats–Redfern and Piloyan–Novikova are reported. The results of kinetics of thermal decomposition suggest contracting cylinder model as the one that is relevant to the decomposition of CdTiO₃. The kinetic parameters viz. the order of reaction, activation energy, frequency factor, and entropy of activation using the above mentioned models are computed.     

数控冲床送料机构交流伺服电机动力参数计算与选型

对数控冲床送料机构交流伺服电机相关动力参数作了系统的分析，推出了交流伺服电机各参数选取的计算式，并举例了东莞东华公司的LX328数控冲床的送料机构电机设计选型实例．     

Individual Differences in Susceptibility to False Memory in the Deese-Roediger-McDermott Paradigm.

The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than individuals with reduced WMC when participants were forewarned about the tendency of associative lists (e.g., bed, rest, . . .) to elicit illusory memories for critical words (e.g., sleep). In contrast, both high and low WMC participants used repeated study-test trials to reduce recall of critical words. These findings suggest that individual differences in WMC influence cognitive control and the ability to actively maintain task goals in the face of interfering information or habit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

永磁交流伺服电动机定位转矩的消除方法

以一台具有特殊设计要求的永磁交流伺服电动机为例，介绍斜槽角度的选择方法及小值定位转矩的计算方法。     

柔性交流输电系统重点设备分析

随着电力系统的发展 ,对电网的稳定性和传输能力要求越来越高 ,但我国电力建设资金有限 ,只有通过改进技术来满足电网的要求 ,FACTS设备就能达到这一目的 ,本文就对几种FACTS的关键设备进行了对比和详述。