正交设计与回归分析在水泥快速测定中的应用

一、内容提要 衡量水泥质量的现行国家标准(GB164—82)是采用养护28天的水泥胶砂强度来评定的.本文通过正交设计法安排试验条件,用回归分析法计算试验指标,对本钢建材厂生产的钢渣矿渣水泥,采用促凝压蒸法1.5小时强度来推定28天的强度.找出较佳的试验条件;进而在该条件下进行重复试验;最后得出在该条件下1.5小时强度与28天强度的回归方程.这对加快水泥生产,保证工程的质量和进程,有着很大的现实意义. 二、用正交法找出促凝压蒸法的最使试验条件 对本钢建材厂生产的钢渣矿渣水泥,采用国家规定的 4 X 4 X 16CC的试模,首先设法找出影响1.5…     

基于灰色聚类的多指标稳健性设计研究

随着市场竞争的日趋激烈,迫切地需要将产品的质量、成本、效益和顾客的满意度等市场竞争要素一起综合考虑进行稳健性设计.采用灰色聚类多指标综合评价对定性、定量指标用灰数的白化权函数加以聚类,对试验方案进行初步筛选,然后在备选方案中对同属于"优"类别的方案进行综合分析,得到一组最佳可控因子组合,并进行验证性分析.最后利用此方法对一款洗衣机用串激电机从成本、效益和顾客满意度方面综合进行考虑,进行了稳健性设计,得到真正意义上的低成本、高质量、高可靠性和高效益的产品,从而最终为解决这种带有模糊性因素的多指标优化问题开创了一种稳健性设计新思路.     

D-最优试验设计在低标号砌筑水泥研制中的应用

本研究是在Ｄ－最优试验设计的基本理论指导下进行的，在砌筑砂浆胶结料的研制过程中，发现得到的８个指标的数学模型与实测试验结果拟合的精度非常高．并且胶结料的性能与１２５＃砌筑水泥非常相近，只是２８天抗压强度指标稍差，鉴于胶结料单一产品尚无国家标准，为使生产厂家便于控制质量，故以此模型为基础，在约束条件下经模型外推直接找出了１２５＃砌筑水泥的优化配比，经验证，全部指标都符合国家标准的要求．     

水泥强度快速测定方法的研究

一、问题的提出 通常对挤压成型的水泥强度进行测定 时,总是先将成型的水泥浸泡在水中,经 二十八个昼夜后,再取出测量.这样时间 过长,浪费人力、物力,对于施工单位, 问题就更加严重,常常是水泥用完了,而 其强度还未测出. 为了减少试验时间,采用一种新方 法,将成型水泥放在60℃的油中泡一小 时,取出后再在100℃的沸水中泡五小时, 然后测定其强度,或在沸水中泡六个小 时,然后取出测定其强度.这样就大大缩 短了水泥强度测试的时间.从二十八个昼 夜缩短至六个小时,提高工效一百十二 倍.这种方法称水泥强度快速测定法. 问题是用快速法测定的水泥…     

均匀设计优化烧伤油一号的制备条件

采用均匀设计以及拟水平法 ,对可能影响烧伤油一号质量的 3个因素进行试验考察。并对试验结果运用偏最小二乘法与残差分析进行回归分析。分析结果表明 :烧伤油一号最佳工艺条件是 :紫草种类 :紫草 ;油温 :175℃ ;浸渍时间 :19小时。采用优选制备条件实验表明 ,优选工艺是可信的。     

考虑绕行特征的电动汽车快速充电站选址问题及自适应遗传算法

快速充电站选址是电动汽车运营的重要内容之一。本文考虑电动汽车用户会通过绕行一定距离对车辆进行充电这一特征,建立了一个以电动汽车快速充电站建站成本和旅客整体绕行成本之和最小的双层整数规划模型。本文首先给出了用于生成绕行路径集合的A^*算法,然后设计了一种包含局部迭代搜索的自适应遗传算法对该模型进行求解。为了测试算法性能,通过两个不同规模的算例图与已有求解FPLM问题的遗传算法进行了比较,数值试验部分证明了算法的正确性和有效性。最后引入浙江省的高速路网图,从建站成本和截流量两方面对电池续航里程带来的影响进行了相关的灵敏度分析。     

拟因子试验设计在生产中的应用

根据生产实际,综合利用并列、赋闲列和拟水平试验设计,运用多重比较进行方差分析,寻找水泥熟料的最佳工艺.不仅解决了不同水平多因素试验问题,同时还可考虑交互作用,大大减少了试验次数,从而提高经济效益.     

DMAIC流程在自动焊接质量改进中的应用

本文按照六西格玛DMIAC流程对A企业自动焊接质量进行改进.按照DMAIC流程对问题进行定义,明确改进目标。然后测定导致自动焊质量问题的可能原因,并对相关测量系统的能力进行评定和改进.在此基础上进一步分析导致质量问题的根本原因,并设计了一个2~((-2))试验方案,找出影响焊接缺陷的显著因素并进行优化,使得自动焊过程的缺陷水平降为DPHU低于0.05,超过了预期目标,成本节省显著。最后,为了保持改进成果,对过程建立了适当的在控制方法.     

橡胶输送带复盖胶配方的优化

橡胶配方的优化是一个多因素多指标的复杂课题,运用正交试验设计方法进行配方设计,将通过试验获得的数据藉助微机进行回归分析和优化计算,从而取得最优配方,是橡胶企业提高经济效益的一种较有效的方法. 浙江省某橡胶厂生产的橡胶输送带,年产量在100万平方米以上.在生胶与各种化工原料竞相提价,产品市场竞争激烈的环境中,企业只有加强质量管理,不断提高产品质量并降低成本,才能得以生存和发展.橡胶输送带中耗生胶量最多的部件是复盖胶层,占产品总耗胶量的55%,而该部件胶料质量要求高,成本也较大. 为了获得配方中各成份的改变对复盖胶各项物理…     

兼顾效率和成本的ARMA控制图多目标优化设计

ARMA控制图是一种有效的自相关过程质量监控方法,为了能够同时对ARMA控制图监控方案的效率和成本进行优化,本文分别研究了ARMA控制图的平均运行长度和质量成本的计算方法,并由此建立了ARMA控制图的多目标优化设计模型。采用NSGA-Ш智能优化算法,通过一个具体的算例对该模型的计算方法进行了说明,针对不同程度的过程偏移给出了多目标优化设计的非劣解解集。然后通过灵敏度分析的方法研究了模型中的主要设计参数对监控方案的效率和成本的影响程度。最后,通过与其它几种ARMA控制图优化设计方案的比较分析,说明了本文提出的设计方法的优势。     

我国水泥工业的市场统计分析与预测

本通过建国后水泥每年总产量及其相关数据的统计分析,找出了水泥需求制约和影响的主要因素,对水泥产量进行短期预测,并参照世界发达国家的水泥生产发展过程,结合我国实际,对我国的水泥总产量建立数学模型,进行中长期预测。     

A theoretical evaluation method for mechanical sealing integrity of cementing sheath

The sealing integrity of cement sheath directly affects the service life of oil and gas wells, and plays an important role in oil well operation and production. In this paper, the evaluation of sealing integrity of cement sheath was divided into two parts: the integrity of formation and cement sheath, and the integrity of cement sheath and casing. Based on the convergence-constraint theory, the effect of convergence stress generated by formation on cement slurry during the hardening process was considered. And the evaluation method for casing-cement-formation sealing integrity was established. In addition, a quantitative relationship between compressive strength of cement sheath and formation characteristic parameters was proposed to determine the cement-formation sealing integrity. Besides, the integrity evaluation method of casing-cement-formation combination was verified by tensile strength, compressive strength and plastic zone of cement. The field application analysis showed that this method is valid to predict the cement failure. During the cementing operation, the integrity of casing-cement-formation interface can be controlled by adjusting the properties of the cement sheath.     

低密度和高密度水化硅酸钙的纳米压痕数值模拟

水化硅酸钙(C-S-H)是决定以硅酸盐水泥为主要组分的水泥基材料性能的关键组分,水化硅酸钙(C-S-H)是存在于水化产物中连续的固体物质,占水化水泥浆体体积的50%～60%,是水泥浆体中决定硬化水泥浆体物理结构和性能的主要成分,同时水化硅酸钙(C-S-H)也是混凝土结构宏观尺度的凝聚性和耐久性的重要影响因素．模型的建立对于预测水泥的体积性能如收缩、蠕变、渗透率和裂缝等方面越来越重要．通过将水化硅酸钙(C-S-H)分为低密度和高密度两种数值模型,并且将水化硅酸钙(C-S-H)视为在纳米尺度上具有实际微观粒子性能的离散颗粒的集合,运用分子动力学方法,通过控制水化硅酸钙(C-S-H)的紧密堆积体积分数和保持颗粒级别的其他材料属性不变来进行纳米压痕实验模拟,进而验证了压痕模量和硬度符合纳米压痕实验数据的规律．     

Evaluating the strategic behavior of cement producers: An equilibrium problem with equilibrium constraints

This paper investigates the equilibria reached by a number of strategic producers in the cement sector through a technological representation of the market. We present a bilevel model for each producer that characterizes its profit maximizing behavior. In the bilevel model, the upper-level problem of each producer is constrained by a lower-level market clearing problem representing cement trading and whose objective function corresponds to social welfare. Replacing the lower level problem by its optimality condition yields a Mathematical Program with Equilibrium Constraints (MPEC). Then, all strategic producers are jointly considered. Representing their interaction requires solving jointly the interrelated MPECs of all producers, which results in an Equilibrium Problem with Equilibrium Constraints (EPEC).A parametric analysis concerning cost, capacity and demand fluctuations has been conducted. Our analysis shows that the European cement sector is mature and has lost its competitiveness; African cement market can assume a prominent role in international markets in the coming future if investments in new and efficient capacity are carried out. Finally, the Far East will remain the reference exporter of cement at worldwide level.     

Maritime inventory routing with multiple products: A case study from the cement industry

This paper considers a maritime inventory routing problem faced by a major cement producer. A heterogeneous fleet of bulk ships transport multiple non-mixable cement products from producing factories to regional silo stations along the coast of Norway. Inventory constraints are present both at the factories and the silos, and there are upper and lower limits for all inventories. The ship fleet capacity is limited, and in peak periods the demand for cement products at the silos exceeds the fleet capacity. In addition, constraints regarding the capacity of the ships’ cargo holds, the depth of the ports and the fact that different cement products cannot be mixed must be taken into consideration. A construction heuristic embedded in a genetic algorithmic framework is developed. The approach adopted is used to solve real instances of the problem within reasonable solution time and with good quality solutions.     

Numerical investigations on autogenous shrinkage of cement paste and mortar

Autogenous shrinkage of cement paste and concrete is defined as the macroscopic length change occurring with no moisture transferred to the exterior surrounding environment. It is a result of chemical shrinkage affiliated with the hydration of cement particles and the ongoing process of self-desiccation. The process of self-desiccation can be modeled starting from the formation of the capillary pore space during hydration in the cement paste. In this proposal a working model will be introduced explaining the difficulties to obtain the autogenous shrinkage strains directly from a simulated or measured microstructure of cement paste. In a second step the autogenous shrinkage of a hardening cement mortar was described on a mesoscopic level. It based on measurements on cement paste. The mortar simply consists of cement paste and a defined fraction of spherical aggregates with a known modulus of elasticity. Furthermore the influence of the interfacial transition zone (ITZ) is studied in numerical simulations. The results of these finite-element-calculations are introduced and compared with testing results of the autogenous shrinkage of hardening mortar samples. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

水泥强度的模糊预测模型研究

本文根据水泥强度的模糊性 ,运用模糊模式识别理论 ,建立了预测水泥强度的模糊贴近度模型 .通过对上海水泥厂提供的实测数据进行模糊计算 ,得到了令人满意的结果 ,为水泥强度的快速预测提供了一种新方法 ,有较好的实用价值 .     

Repairing force for deformed casing shaping with spinning casing swage and damage behaviour of cement sheath

In oil and gas fields, the repairing force (bit weight) is generally determined by experience when the deformed casing is repaired using the spinning casing swage. However, unreasonable repairing force easily damages the cement sheath around the deformed casing and causes pipe sticking, which results in failure of the wellbore integrity. Hence, based on the Hertz contact theory, the present study established a mechanical model to calculate the repairing force required to repair the deformed casing without a cement sheath by spinning casing swage, and the reshaping force was determined by combining the structural features of the spinning casing swage with the method of mechanics and kinetics analysis regarding axial loading and circumferential deformation of the deformed casing. Finally, a mechanical model was presented that could calculate the repairing force of the deformation casing with cement sheath using the inversion method. Repairing experiments involving three types of deformed casings (casing without cement sheath, casing with undamaged cement sheath and casing with damaged cement sheath) were performed, from which the accuracy and reliability of the mechanical model was validated. The damage behaviour of the cement sheath after casing repair was investigated based on the experimental results and the damage mechanism was analysed based on Saint-Venant's deformation compatibility principle. Analysis results showed that three types of damage, including micro-annulus, transverse fracture and longitudinal fracture, were caused by high contact pressure between the steel ball on the spinning casing swage and the internal wall of the deformed casing and pressure fluctuation during repairing. The research results provide important guidance and decision making for practical repairing measures.     

水泥产品结构的综合智能优化及应用研究

根据水泥市场需求信息,运用自适应模糊推理系统对水泥产品结构需求进行系统建模,应用并行遗传算法对模型求解,得到了来年的最优水泥产品结构需求计划,为水泥企业的生产规划及其经济效益的提高提供了重要的参考价值.     

Elastic characteristics of a cement-based composite reinforced with steel grid ribbons

A method is proposed for the estimation of elastic characteristics of a cement mortar orthogonally reinforced with punched steel grid ribbons. The method proposed takes into account the geometry of grids, the distance between ribbons, and the elastic properties of cement mortar and steel.