4000吨/年硫磺回收装置真空带式过滤机技术改造

介绍了陕西延长石油集团延安石油化工厂硫磺回收装置真空带式过滤机从开工运行到实施技术改造前存在的问题,包括:机架和机座腐蚀问题,裙边的老化后产生的开裂、脱落问题,滤布的纠偏问题,控制系统问题,排水系统问题,现场通风问题,轴承座防腐问题,胶带防偏等问题,并进行了改造,改造后过滤机运行良好。     

基于问题链设计的“化工过程分析与合成”教学探索与实践

问题链教学模式以一系列层层递进逻辑关系的问题为纽带,以课程目标和学生思维能力培养为主线,以师生互动合作为基本形式。在“化工过程分析与合成”教学中采用问题链教学模式,通过导学型问题链、驱动型问题链、迁移型问题链、归纳型问题链和拓展型问题链,激发学生对知识的学习兴趣、积极性和主动性,同时提升学生的工程思维能力和解决复杂工程问题的能力。     

玻璃幕墙玻璃的选用

玻璃幕墙的大量使用,随之而来的节能问题、光污染问题、安全防火问题等不容忽视,这些问题都与幕墙玻璃的选择有直接关系,换句话说玻璃幕墙问题的关键主要是玻璃的选择。     

装配式建筑生产施工质量问题与改进举措研究

装配式建筑作为一种高效且可持续的建筑方法,在建筑行业中不断崭露头角。然而,在其生产施工过程中仍然存在着一系列质量问题,这些问题直接影响到建筑项目的质量、性能和安全性。笔者通过探讨装配式建筑生产施工中常见的质量问题,如设计不一致性、设计变更和沟通问题、原材料质量控制问题、制造工艺问题、运输损伤问题、装配不准确问题以及施工标准执行问题,并提出改进举措,以确保装配式建筑项目的质量和可持续性。     

基于问题导向的分析化学课程理实一体化教学模式探索

针对分析化学课程特点以及传统教学方法中存在的问题,探讨基于问题导向的理实一体化教学模式的方法。结果表明:理实一体化有助于解决理论实践脱节问题,强化学生理论水平;以“5W”为代表的问题导向教学模式可以提高学生学习主动性,提高学生发现问题、分析问题和解决问题的能力,有助于增强学生运用理论知识解决实际问题的意识和能力。     

涂装电泳、PVC技术质量浅析

1浅析白车身电泳时存在的质量问题1.1存在的质量问题在涂装生产中,前处理-电泳往往会出现很多的问题,在车身备件的涂装生产中出现的问题则更多,如:工装设计造成的质量问题;脱脂不良时易出现的油污处理     

电气安装工程中照明配电箱安装存在问题及预防措施论述

配电箱出现问题,会包含配电箱本身质量问题以及接线的方法问题和在安装中所使用的技术等几个问题,我们就此展开分析提出预防措施,为今后施工当中遇到同样的问题提供意见和建议。     

大型离心式压缩机运行过程中存在的问题分析

本文对离心式压缩机在运行过程中的喘振问题、噪声问题、润滑油酸值高问题、轴承故障问题、旋转脱离问题等发生的原因和表现进行了详细分析。     

有关环境与环境保护问题的探讨

对环境问题和环境价值等环境保护的基本概念和理论问题作了初步探讨，认为人是社会关系的总和与自然关系的总和的统一，环境问题本质上是人的问题，尊重环境的价值是人类解决环境问题的一个主要环节。     

书与画浅谈

中国画绵延了千年的安宁和辉煌来到现在,渐渐出现了众多的问题。出现这些问题的起因,或者说是这些问题的主因,其实是中国画的所谓当代化的问题。中国画的前世顺理成章了,中国画的今生呢?似乎谁都觉得出现了问题。那么中国画,或者说中国艺术,是否也是一个当代化的问题呢?作为特立的中国     

A MILP model for N-dimensional allocation

This paper presents a Mixed Integer Linear Programming (MILP) model for the solution of N-dimensional allocation problems. The applicability of the model is presented and demonstrated through some illustrative examples with different numbers of dimensions. Several problems, previously presented in the literature, are solved using the proposed model, such as, one-dimensional scheduling problems, two-dimensional cutting problems, as well as plant layout problems and three-dimensional packing problems. Additionally, some problems in four dimensions are presented and solved using the considered model. The presented model is applicable to a wide variety of allocation problems as it offers a general framework for modelling allocation problems with any given number of continuous or discrete dimensions. The presented problems are formulated as MILP problems where the first four dimensions usually are continuous spatial and time dimensions. Additional dimensions are often of a discrete nature.     

加氢裂化装置开工过程出现的问题分析及处理

阐述了加氢裂化装置在开工过程中出现的问题,对问题产生的原因进行了分析,继而总结了处理的方法,提出了避免发生类似问题的看法。     

A Review of Ozone Generating Facilities in Some U.S. Water and Wastewater Treatment Plants

In previous years, the start-up and operation of ozone systems at U.S. municipal water and wastewater treatment facilities has resulted in numerous problems. Some of these problems were of such a magnitude that the operating agency decided to abandon the ozone system. In other cases, the system is operating and the problems are resolved. An investigation of 11 U.S. facilities was conducted to determine what problems were experienced and how the problems were resolved.     

轮胎接触问题的分析与研究

简要地综述了轮胎接触问题分析的发展过程及所使用的一些方法，着重介绍了三维有限元法在轮胎接触问题中的应用，同时也概括了弹性力学理论及实验测试在轮胎接触问题中的应用。本文对轮胎接触问题的分析主要是围绕静态接触和滚动接触两方面展开论述的，列出了轮胎接触问题中轮胎变形、接触区形状大小、接触压力分布、应力分布、载荷变形关系、内轮廓形状等结果     

Optimizing Injection Molding Toward Multiple Quality and Cost Issues

Injection-molding part designers are frequently faced with multiple quality and cost issues. These issues are usually in conflict with each other; thus, a trade-off needs to be made to reach a final compromised solution. Because evaluation of part quality and cost via injection-molding simulation is very time-consuming, implementation of a conventional multicriteria optimization procedure for injection-molding problems is economically unfavorable. However, many injection-molding problems dealing with multiple quality and cost issues can be modeled as constrained problems, with the total cost as the objective function and quality quantities as the constraints. By introducing a concept of penalized total cost, such constrained problems are further simplified into bounded single-criterion problems. The bounded single-criterion problems are then optimized using a direct search-based optimization procedure. Strategies of modeling, transformation, and optimization for these problems are discussed in this article. A case study is provided.     

PARALLEL SOLUTION OF DISJUNCTIVE MINLP PROBLEMS

In this paper, a system for parallel solution of large scale disjunctive optimization problems is presented. Disjunctive optimization problems occur in process engineering; both in production scheduling and in process synthesis. In general these problems are computationally very hard to solve.

This system combines the demands of process engineering optimization problems with the potential CPU-power of the computers connected to the Internet. The system is capable of using an arbitrary number of computers connected to the Internet for distributed solution of rigorous industrial optimization problems.     

涂装风机设备调试问题解决方法探讨

通过汽车涂装风机设备在调试过程中所遇到的问题，结合现场情况，从整个设备的设计图、安装、调试以及工作环境等进行问题分析、排查，分析问题原因并提出相应解决方法和步骤，找出可能存在的问题，直到最终解决问题、     

A global optimization algorithm (GOP) for certain classes of nonconvex NLPs—II. Application of theory and test problems

In Part I (Floudas and Visweswaran, Computers chem. Engng 14, 1397, 1990), a deterministic global optimization approach was proposed for solving certain classes of nonconvex optimization problems. An algorithm, GOP, was presented for the rigorous solution of the problem through a series of primal and relaxed dual problems until the upper and lower bounds from these problems converged to an -global optimum. In this paper, theoretical results are presented for several classes of mathematical programming problems that include: (i) the general quadratic programming problem; (ii) quadratic programming problems with quadratic constraints; (iii) pooling and blending problems; and (iv) unconstrained and constrained optimization problems with polynomial terms in the objective function and/or constraints. For each class, a few examples are presented illustrating the approach.     

Solving mixed integer nonlinear programming problems with line-up competition algorithm

Line-up competition algorithm (LCA), a global optimization algorithm proposed recently, is applied to the solution of mixed integer nonlinear programming (MINLP) problems. Through using alternative schemes to handle integer variables, the algorithm reported previously for solving NLP problems can be extended expediently to the solution of MINLP problems. The performance of the LCA is tested with several non-convex MINLP problems published in the literature, including the optimal design of multi-product batch chemical processes and the location-allocation problem. Testing shows that the LCA algorithm is efficient and robust in the solution of MINLP problems.     

环境统计工作存在的问题及解决方法

我国自1983年开展环境统计工作以来,环境统计范围不断扩展,环境统计制度不断完善,环境统计数据在综合反映环境状况、服务环境管理和科学决策方面起到了重要的基础性作用。随着我国经济的快速发展,环境问题越来越受到重视,对环境统计数据的需求越来越多,对环境统计在全面性、及时性、准确性以及综合分析等方面提出更高的要求。现行的环境统计已不适应形势发展的需要,必须进行改革。要加强环境统计工作改革步伐,简化指标,提高效率,要及时、准确地提供统计数据,客观地反映经济发展与环境形势的变化,真正为环境管理和决策服务。