自由曲面结构形态创构方法——高度调整法的建立与其在工程设计中的应用

曲面结构(如壳体)的受力性能主要取决于结构的曲面形状。在实际工程中,常规的简单曲面一般较难有效满足结构的受力合理性。利用曲面高度参数与结构应变能之间的关系,提出了一种自由曲面创构方法来保证结构达到“薄”而“刚”的统一。该方法基于有限元法,通过计算应变能对曲面高度的微分,并根据应变能变化的敏感程度对曲面高度进行调整,最终得到一个结构应变能最小的合理结构形态。利用该方法,可以通过调整设计参数(约束条件,空间条件)得到多种合理曲面形态,供设计人员参考。同时,也可以对建筑意图所设定的初始形状进行修改,求得近似合理的结构几何形状。工程设计实例表明,该方法所得到的曲面结构基本以薄膜应力为主,而且能保证足够的刚度。     

MATLAB软件在土木工程数值计算中的应用

MATLAB软件具有简单易学、代码短小、计算功能强大等特点，适用于数据处理。就土木工程中的一些数值计算问题，借助MATLAB软件帮助求解，展示了MATLAB软件解决数值计算问题简捷、快速和准确的优势。     

一类全系数模糊规划问题及其求解方法

模糊规划是不确定规划的重要一类,对许多带有模糊信息的实际问题都能进行有效地处理,对模糊规划的求解方法进行讨论不仅具有理论意义,还具有实际意义.为寻求一类全系数模糊规划问题的求解方法,利用三角(或梯形)模糊数的排序准则并结合禁忌搜索算法设计了一种求解系数均为三角(或梯形)模糊数的规划模型的人工智能算法.数值算例表明笔者所提方法行之有效.     

Artificial lift infrastructure planning of shale gas horizontal wells considering endogenous and exogenous uncertainties

Artificial lift methods (ALMs) lift the accumulated fluids from horizontal shale-gas-producing wells and help sustain well performance. An artificial lift infrastructure plan includes the selection of ALMs and their operating schedule. This paper presents two discrete-time large-scale nonconvex mixed-integer nonlinear programming models to solve the artificial lift infrastructure planning problem. Two equivalent mixed-integer linear programming models are formulated using the special structure of the nonlinear terms. A set of valid inequalities is defined to tighten the models and shorten solution times to two orders of magnitude, considering well production limitations. We incorporate endogenous uncertainty in ALM-dependent production rates and exogenous uncertainty in shale gas prices into the models. For a hypothetical case study under only endogenous uncertainties, the value of the stochastic solution is 5%. For the same case study, the exogenous uncertainty in gas prices does not change the optimum solution.     

Optimization of a multiperiod refinery planning problem under uncertainty

Uncertainty in refinery planning presents a significant challenge in determining the day-to-day operations of an oil refinery. Deterministic modeling techniques often fail to account for this uncertainty, potentially resulting in reduced profit. The stochastic programming framework explicitly incorporates parameter uncertainty in the problem formulation, thus giving preference to robust solutions. In this work, a nonlinear, multiperiod, industrial refinery problem is extended to a two-stage stochastic problem, formulated as a mixed-integer nonlinear program. A crude-oil sequencing case study is developed with binary scheduling decisions in both stages of the stochastic programming problem. Solution via a decomposition strategy based on the generalized Benders decomposition (GBD) algorithm is proposed. The binary decisions are designated as complicating variables that, when fixed, reduce the full-space problem to a series of independent scenario subproblems. Through the application of the GBD algorithm, a feasible mixed-integer solution is obtained that is more robust to uncertainty than its deterministic counterpart.     

Simultaneous synthesis of heat-integrated water networks by a nonlinear program: Considering the wastewater regeneration reuse

Heat-integrated water network synthesis (HIWNS) has received considerable attention for the advantages of reducing water and energy consumptions. HIWNS is effective in water and energy sustainability. Mixed integer non-linear programming (MINLP) is usually applied in HIWNS. In this work, a novel nonlinear programming (NLP) was proposed for HIWNS by considering wastewater reuse and wastewater regeneration reuse. Integer variables are changed to non-linear equation by the methods for identifying stream roles and denoting the existence of process matches. The model is tested by examples with single and multiple regeneration unit problems. The testing results showed that the NLP is an alternative method for HIWNS with wastewater reuse and regeneration reuse.     

医院建筑设计的前期策划

无论是医院建筑物的主体空间或是医疗设备的设置，都需充分利用，才能提高使用效率，降低成本。建筑设计的前期策划就是为业主制订详细的任务书及远近期总体规划，使之有计划、有步骤地逐步过渡，实现医院的现代化。     

供热系统优化规划方法研究

提出了适用于供热系统的两级优化规划方法，即第一级的布局优化和第二级管网的多目标优化方法。运用最优化理论建立的布局优化模型和管网系统多目标优化模型及采用的求解方法，适用于所有具有“管一站”网络特征的系统。     

连体筒仓滑模的几项新技术

七五生建煤矿装车仓为两连体筒仓，采用滑模工艺，滑模施工中解决了筒壁与漏斗分离施工问题，选滑升筒壁，使可滑位置从漏斗楼面降至-3.800m基础面；解决了6m宽洞口围圈刚度小及1.2m高外突环梁空滑时支承杆失稳问题，模板装置构造简单，易于操作，辅助平台和操作平台采用型钢方案，简化了结构形式且安折方便。     

配电系统中变电站智能化升级策略

代表变电站技术发展趋势的智能变电站是智能电网的重要组成部分。智能变电站的配置对系统安全与经济运行具有重要影响,是值得研究的重要问题。在此背景下,研究了计及可靠性的配电系统中变电站智能化升级问题。首先,以变电站智能化升级成本和用户停电损失之和最小化为目标函数,考虑系统平均停电时间(system average interruption duration index,SAIDI)和电量不足平均值(average energy not supplied,AENS)这2个可靠性指标不超过给定阈值等约束条件,构建了配电系统中变电站的智能化升级优化模型。之后,发展了针对配电系统故障的故障清除模型,提出了评估用户停电时间的比较准确的方法。接着,对用户停电时间和用户停电损失函数进行线性化处理,得到变电站智能化升级问题的混合整数线性规划模型,并采用高效商业求解器求解。最后,以IEEE RBTS-Bus 4配电系统和丹麦某中压配电系统为例来说明所提方法的基本特征。