基于熵测度的自适应遗传算法

针对基本遗传算法SGA在搜索过程中易陷入局部最优解的问题,提出了基于熵测度的自适应遗传算法,并分析了熵测度下种群个体被选概率的极限行为。理论分析和对比实验表明,基于熵测度的自适应选择策略能根据种群性状来动态地调整选择压力,从而调整算法的开采和探索能力的平衡,提高算法的全局优化性能。     

水工混凝土结构设计分项系数取值方案探讨

介绍了《水工混凝土结构设计规》（修订稿）关于承载能力极限状态设计表达式中分项系数的确定方法和取值方案．可靠度分析结果表明，按所建议的分项系数取值方案设计的水工混凝土结构构件，在不同设计条件下均具有较佳的可靠度一致性     

最大熵谱估计的算法研究

对最大熵谱估计的几种算法进行了分析和比较，并简要介绍了最大熵谱估计技术的发展前景。     

路基容许不均匀沉降控制指标的理论分析

为了研究路基不均匀沉降的控制指标,利用数值计算的方法,研究路基不均匀沉降的沉降梯度对基层底部附加应力的影响;并基于双层弹性连续体系,求解不均匀沉降在半刚性基层底部产生的弯拉应力,最后利用麦克劳林展开式进行简化。研究结果表明:利用沉降梯度作为路基不均匀沉降的控制指标,具有一定的局限性;而沉降梯度与沉降距离的比值,即一阶梯度,与弯拉应力之间存在一一对应的关系,可作为容许不均匀沉降的控制指标。对于我国典型的半刚性路面结构来说,不考虑车辆荷载时,路基不均匀沉降的容许一阶梯度可取为0.000161m-1。     

Selection of regression models for predicting strength and deformability properties of rocks using GA

Recently, many regression models have been presented for prediction of mechanical parameters of rocks regarding to rock index properties. Although statistical analysis is a common method for developing regression models, but still selection of suitable transformation of the independent variables in a regression model is difficult. In this paper, a genetic algorithm (GA) has been employed as a heuristic search method for selection of best transformation of the independent variables (some index properties of rocks) in regression models for prediction of uniaxial compressive strength (UCS) and modulus of elasticity (E). Firstly, multiple linear regression (MLR) analysis was performed on a data set to establish predictive models. Then, two GA models were developed in which root mean squared error (RMSE) was defined as fitness function. Results have shown that GA models are more precise than MLR models and are able to explain the relation between the intrinsic strength/elasticity properties and index properties of rocks by simple formulation and accepted accuracy.     

高层建筑结构振动控制的一种瞬态最优控制算法

提出了一种适用于高层建筑结构振动控制的瞬态最优控制算法。该算法以求一个时变的二次型性能指标的最小值为目标，采用Ｎｅｗｍａｒｋ法求解最优控制力和结构的响应，使每一瞬时的性能指标取最小值。文中详细地分析了该算法，给出了编程方法和框图。     

Study of high efficiency of evaluation of a PDP in authorization service

In authorization service, the efficiency of evaluation of a PDP(policy decision point) is a key issue that affects the efficiency of authorization service. However, the efficiencies of evaluation of many PDPs available are frequently influenced by the factors of conditions in rules. Said Marouf et al put forward a method in which the evaluation speed can be increased by adjusting the rules in policies according to user history access records. This paper analyzes the shortcomings of this method in real-time applications, and proposes that the rules order in policies can be instantaneously adjusted by user history access records and indexes as well as self-adaptation are added to a PDP so that the evaluation speed can be increased substantially. Experimental results indicate that when there are 9795 rules in a PDP, the evaluation time and the time consumption taken for a PDP applied with indexes and self-adaptation to complete an authorized operation call are shortened by 93.33％ and 76.32％ respectively, compared with those for a PDP which is not applied with indexes and self-adaptation. When the number of repeat visits from the same user is 7, the time consumption taken for a PDP applied with indexes and adaptation to complete an authorized operation call is shortened by 24.29％ compared with that for a PDP which is applied with indexes only.     

实训课程教学质量多层灰关联综合评价

为建立实训课程教学质量综合评价体系,从实训准备、实训过程、实训内容、教学态度、实训效果等5个方面构建评价指标体系,采用层次分析法计算指标权重,采用灰色关联分析法构建多层综合评价模型;某系对学期末开设的5门单独设置实训课进行综合评价,其教学质量参差不齐,反映出该系亟需加强对单独设置实训课的管理与监控.     

一种基于文本先分类再聚类的互联网热点信息发现方法

针对互联网热点信息发现的需求,提出一种基于先分类再聚类的互联网信息热点发现及分析系统构建方法.通过对互联网样本信息文本的特征提取,构建文本向量空间模型,使用Maxent最大熵分类模型对文本进行分类,对分类结果使用OPTICS聚类算法获取文本热点簇,最终获取有效热点信息.实验证明,通过先分类再聚类的方法可以有效避免语义类别不同但字面意义混淆的文章对聚类算法的影响,有效提高聚类结果的精度和运算效率.     

中西医结合治疗高血压合并脑梗死的疗效分析

探讨中西医结合疗法对高血压合并脑梗死患者神经功能和日常生活的影响。实验方法如下：选择高血压合并脑梗死患者70 例,随机分为治疗组与对照组,每组35 例,对照组给以常规西医治疗,治疗组在对照组基础上加服中药汤剂,两组均治疗30 d。结果显示：治疗组总有效率 94.3%,[WTBX]对照组总有效率74.3%,差异显著（P<0.05）。治疗组高血压合并脑梗死患者神经功能的缺损评分明显降低(P <0.05),Barthel指数评分明显升高(P <0.05)。中西医结合治疗高血压合并脑梗死具有很好的效果。