Improvement Detecting Method of Optical Axes Parallelism of Shipboard Photoelectrical Theodolite Based on Image Processing

An improvement detecting method was proposed according to the disadvantages of testing method of optical axes parallelism of shipboard photoelectrical theodolite (short for theodolite) based on image processing. Pointolite replaced 0.2'' collimator to reduce the errors of crosshair images processing and improve the quality of image. What’s more, the high quality images could help to optimize the image processing method and the testing accuracy. The errors between the trial results interpreted by software and the results tested in dock were less than 10'', which indicated the improve method had some actual application values.

Operation safety risk analysis method of hydropower project considering time-dependent effect

In order to consider the time-dependent characteristic of risk factors of hydropower project,the method of stochastic process simulating structure resistance and load effect is adopted.On the basis of analyzing the structure characteristics and mode of operation,the operation safety risk rate assessment model of hydropower project is established on the comprehensive application of the improved analytic hierarchy process,the time-dependent reliability theory and the risk rate threshold.A scheme to demonstrate the time-dependent risk rate assessment method for an example of the earth-rock dam is particularly implemented by the proposed approach.The example shows that operation safety risk rate is closely related to both the service period and design standard;considering the effect of time-dependent,the risk rate increases with time and the intersection of them reflects the technical service life of structures.It could provide scientific basis for the operation safety and risk decision of the hydropower project by predicting the trend of risk rate via this model.

The Objective Function Value Optimization of Cloud Computing Resources Security Allocation of Artificial Firefly Algorithm

Based on the current cloud computing resources security distribution model’s problem that the optimization effect is not high and the convergence is not good, this paper puts forward a cloud computing resources security distribution model based on improved artificial firefly algorithm. First of all, according to characteristics of the artificial fireflies swarm algorithm and the complex method, it incorporates the ideas of complex method into the artificial firefly algorithm, uses the complex method to guide the search of artificial fireflies in population, and then introduces local search operator in the firefly mobile mechanism, in order to improve the searching efficiency and convergence precision of algorithm. Simulation results show that, the cloud computing resources security distribution model based on improved artificial firefly algorithm proposed in this paper has good convergence effect and optimum efficiency.

Deep Learning Applied to Computational Mechanics:A Comprehensive Review,State of the Art,and the Classics

Three recent breakthroughs due to AI in arts and science serve as motivation:An award winning digital image,protein folding,fast matrix multiplication.Many recent developments in artificial neural networks,particularly deep learning(DL),applied and relevant to computational mechanics(solid,fluids,finite-element technology)are reviewed in detail.Both hybrid and pure machine learning(ML)methods are discussed.Hybrid methods combine traditional PDE discretizations with ML methods either(1)to help model complex nonlinear constitutive relations,(2)to nonlinearly reduce the model order for efficient simulation(turbulence),or(3)to accelerate the simulation by predicting certain components in the traditional integration methods.Here,methods(1)and(2)relied on Long-Short-Term Memory(LSTM)architecture,with method(3)relying on convolutional neural networks.Pure ML methods to solve(nonlinear)PDEs are represented by Physics-Informed Neural network(PINN)methods,which could be combined with attention mechanism to address discontinuous solutions.Both LSTM and attention architectures,together with modern and generalized classic optimizers to include stochasticity for DL networks,are extensively reviewed.Kernel machines,including Gaussian processes,are provided to sufficient depth for more advanced works such as shallow networks with infinite width.Not only addressing experts,readers are assumed familiar with computational mechanics,but not with DL,whose concepts and applications are built up from the basics,aiming at bringing first-time learners quickly to the forefront of research.History and limitations of AI are recounted and discussed,with particular attention at pointing out misstatements or misconceptions of the classics,even in well-known references.Positioning and pointing control of a large-deformable beam is given as an example.

Mathematical Apparatus for Selection of Optimal Parameters of Technical, Technological Systems and Materials Based on Vector Optimization

We presented Mathematical apparatus of the choice of optimum parameters of technical, technological systems and materials on the basis of vector optimization. We have considered the formulation and solution of three types of tasks presented below. First, the problem of selecting the optimal parameters of technical systems depending on the functional characteristics of the system. Secondly, the problem of selecting the optimal parameters of the process depending on the technological characteristics of the process. Third, the problem of choosing the optimal structure of the material depending on the functional characteristics of this material. The statement of all problems is made in the form of vector problems of mathematical (nonlinear) programming. The theory and the principle of optimality of the solution of vector tasks it is explained in work of https://rdcu.be/bhZ8i. The implementation of the methodology is shown on a numerical example of the choice of optimum parameters of the technical, technological systems and materials. On the basis of mathematical methods of solution of vector problems we developed the software in the MATLAB system. The numerical example includes: input data (requirement specification) for modeling;transformation of mathematical models with uncertainty to the model under certainty;acceptance of an optimal solution with equivalent criteria (the solution of numerical model);acceptance of an optimal solution with the given priority of criterion.

Operations Improvement Function and Organisational Adaptability of Petroleum Tank Farms in South-South, Nigeria

The study examined the nexus between operations improvement function (dimensioned by contingency planning, benchmarking and continuous improvement processes) and organisational adaptability of Petroleum tank farms in South-South, Nigeria. The contingency theory and the theory of routine dynamics underpinned the study, and positivism was the underlying philosophy. The study adopted the cross-sectional survey through the use of questionnaire. 820 middle and top-level managers constituted the elements of the population, and the Krejcie & Morgan’s formula was used to determine the sample size of 262 respondents. Structural Equation Modeling was deployed to test the hypotheses at a 0.05 significance level. The results showed that contingency planning;benchmarking and continuous improvement processes all have a significant positive relationship with organisational adaptability of Petroleum tank farms in South-South, Nigeria. The study concludes that Petroleum tank farms’ operations should focus on the adoption of contingency planning, benchmarking and continuous improvement processes to enhance organisational adaptability. Therefore, it is recommended that the management of Petroleum tank farms should put in place mechanisms to advance continuous improvement processes by allocating the necessary amount of resources, such as energy, time and money, in order to promote the continuous development of the continuous improvement systems. Furthermore, managers of Petroleum tank farms should make better the adoption of contingency planning, ensuring that there is as much necessary training and information for employees on how to act during a crises situation, in order to evaluate safety and prepare in advance for recovery from disasters.

基于三维质量结构模型构建手术室环境卫生质量评价指标体系

目的:构建手术室环境卫生质量评价体系,为手术室环境卫生质量监测与管理提供科学、有效、可行的质量管理依据。方法:基于三维质量结构理论模型,采用文献回顾、现场调研、半结构式访谈法,从结构、过程、结果三维度拟定指标体系,通过德尔菲法对15名专家进行两轮函询,确立评价指标条目及指标权重。结果:手术室环境卫生质量评价指标体系包括3个一级指标、13个二级指标和50个三级指标,两轮函询问卷回收率均为100%,专家权威系数分别为0.953和0.959,肯德尔协调系数分别为0.376,0.365(P均<0.001)。结论:本研究构建的手术室环境卫生质量评价指标体系具有科学性、专科性、全面性,为手术室环境卫生质量评价提供了有力的参考依据。

基于IAHP的山岭隧道内已建设施适宜性评价方法

准确评估山岭隧道内已建设施适宜性是利旧原有隧道敷设新管道的核心。针对目前国内缺乏山岭隧道内已建设施适宜性评价方法的问题,将改进层次分析法(IAHP)引入评价过程中,综合考虑利旧前、利旧后2个方面的因素,构建了山岭隧道内已建设施适宜性评价指标体系;针对九分位标度法和三分位标度法的不足,采用指数标度法确定各指标权重,并结合各指标定量或定性评价方法,建立了山岭隧道内已建设施适宜性评价方法,并将该方法运用到实际工程山岭隧道利旧评价中。研究结果表明:评价结果与实际工程情况的结论一致,验证了评价模型的可行性。

集束化管理联合过程导向型教学法在手术室规培教学中的应用

目的探究集束化管理联合过程导向型教学法在手术室规培护士教学中的应用效果。方法采用便利抽样法选取117名手术室规培护士为研究对象,对照组采用传统教学法,观察组采用集束化管理联合过程导向型教学法。结果观察组出科考核成绩、综合素质测评得分、评教得分、临床护理教员教学质量评分满分率均高于对照组(P<0.05)。结论集束化管理联合过程导向型教学法应用于手术室规培护士教学有显著优势,提高了规培护士理论、操作考核成绩及综合能力,激发了学习积极性及主动性,增强了学习效果。

基于改进层次分析法的配网初始规划设计评价方法

配网初始规划设计评价结果的准确性容易受到指标权重计算结果的影响。研究一种基于改进层次分析法的配网初始规划设计评价方法。通过计算累计贡献率选出大于85%的评价指标,构成三层指标体系。引入均衡因子,对层次分析法计算的指标权重进行改进。结合指标权重,利用加权秩和比法计算概率单位值,即配网初始规划效果评分。对照档次划分标准,确定配网初始规划效果档次。结果表明:方案1和方案4的效果达到优秀水平,设计最为合理,可以采纳。

基于层次分析法和作业条件危险性评价法的电力有限空间作业安全风险评估

为了提前预知电力有限空间的作业安全风险,考虑作业中人员、工器具、环境和管理4种重要风险来源,通过层次分析法获取不同风险因素在安全评估中所占的权重。结合作业过程中风险因素实际状态的主观评分,对初始作业条件危险性评价进行适应性调整作为最终评估结果。此外,综合评估了环境风险中多种有毒有害气体的耦合风险。案例分析显示,该方法可操作性强,能较为准确地定量给出作业危险等级。

Multiple Objectives under Uncertainty:IRGSD-FD Method

This paper is devoted to study the multiobjective system programming under the assumption that some of the problem parameters are random variables. A method called Interactive Reference Goal Satisfied Degree and Feasible Degree (IRGSD-FD) is developed to solve stochastic multiobjective problems. It is an interactive method providing a so-called `dialogue' between the user and the model, the decision maker having the option conducting the search process for the (α, β)-efficient solutions by modifying the initial conditions according to the partial results obtained. During the iterations, the decision maker can improve upon the reference goal or called aspiration level already attained by one objective function as well as upon the probability of reaching the corresponding objective or called satisfied degree (or both), or/and the probability of satisfying the constraint or called feasible degree already attained by the constraint. Finally, the application of IRGSD-FD method in the resource allocation problem is discussed with a case study for project investment management.

Layout Design-Based Research on Optimization and Assessment Method for Shipbuilding Workshop

The research study proposes to examine a three-dimensional visualization program, emphasizing on improving genetic algorithms through the optimization of a layout design-based standard and discrete shipbuilding workshop. By utilizing a steel processing workshop as an example, the principle of minimum logistic costs will be implemented to obtain an ideological equipment layout, and a mathematical model. The objectiveness is to minimize the total necessary distance traveled between machines. An improved control operator is implemented to improve the iterative efficiency of the genetic algorithm, and yield relevant parameters. The Computer Aided Tri-Dimensional Interface Application （CATIA） software is applied to establish the manufacturing resource base and parametric model of the steel processing workshop. Based on the results of optimized planar logistics, a visual parametric model of the steel processing workshop is constructed, and qualitative and quantitative adjustments then are applied to the model. The method for evaluating the results of the layout is subsequently established through the utilization of AHP. In order to provide a mode of reference to the optimization and layout of the digitalized production workshop, the optimized discrete production workshop will possess a certain level of practical significance.

基于改进络合铁法的含硫化氢尾气处理工艺模拟与优化

目的有效处理含硫尾气,确保装置“安、稳、长、满、优”运行。方法采用Aspen Plus V11软件基于Peng-Robinson热力学模型对改进络合铁装置的H_(2)S处理过程进行了全流程模拟,并根据Box-Behnken Design对其进行了响应面设计,得到了最佳H_(2)S脱除率及其对应的优化操作参数。结果此模拟流程能够较好地反映改进络合铁装置的实际运行情况,可以作为后续优化研究的基础模型。当循环溶液温度为47.2℃、循环溶液中Fe^(3+)质量分数为8.4100%、循环溶液体积流量为3.12 m^(3)/h、电解槽电压为0.64 V时,改进络合铁装置的H_(2)S脱除率高达99.999988%。此时,外排气中H_(2)S质量浓度为9.5 mg/m^(3),完全可以满足外排气中H_(2)S质量浓度不大于10 mg/m^(3)的约束条件;t检验结果表明,采用响应面法优化得到的预测值和验证值之间不存在显著差异,其准确度一致。结论该研究结果可为进一步提升含H_(2)S尾气处理水平提供准确、可靠的理论支撑和数据来源。

Reliability Measure of a Relay Parallel System under Dependence Conditions

In a relay system of dependent components, the failure to close reliability measure is given as a Girsanov transform of the failure to open reliability measure.

基于密切值决策方法的伊阿铁路走向规划研究

铁路线路方案比选是复杂的多目标决策问题,科学合理的开展线路方案比选对合理确定线路走向极其重要。采用改进密切值决策方法作为铁路线路方案比选的理论支撑,选取建筑长度、桥隧总长、伊阿铁路投资、路网中区域3条铁路的总投资、覆盖经济据点、运量吸引及路网布局等7个因子作为评价指标,利用层次分析法计算评价因子的权重,引入欧氏距离概念得到各方案与最优点和最劣点的“距离”,并计算相应的密切值,进而对线路方案排序择优。以新建伊宁至阿克苏铁路线路走向方案比选为例,结合上述理论方法进行实例研究。研究表明,采用层次分析法计算评价因子权重,采用改进密切值决策方法对方案进行排序择优具有逻辑严谨、形象客观等特点,该方法是适用于铁路线路方案比选的理论方法。

基于改进方法的承德地表水环境质量评价

为客观反映地表水水质状况,采用层次分析法和熵权法组合赋权以及加权平均综合评价原则改进模糊综合评价法,并与单因子评价法、内梅罗指数法、传统模糊综合评价法进行比较,评价承德地区地表水环境质量。结果表明:2021年承德地区地表水水质有明显的时空差异性,除7—9月的部分断面水质为较差外,其余断面水质均在Ⅰ~Ⅲ类;影响承德地区地表水水质的主要因子为COD_(Mn)和TP;单因子评价法和内梅罗指数法无法反映整体水质状况,改进的模糊综合评价法相较于传统模糊综合评价法兼顾了各污染因子间相互作用,并弱化了个别水质指标对评价结果的影响,且能够对同一类别水质进行排序,更适用于承德地区地表水环境质量评价。

AHP-改进物元法在整体钢平台顶升模架体系安全风险评估中的应用

针对整体钢平台顶升模架体系施工安全性的灰色特征,经实地调研及专家评审,建立了整体钢平台顶升模架体系的安全风险评估模型。首先,考虑人员、设备、环境、管理及技术5个方面,选取19个指标构建安全风险评估指标体系;其次,采用层次分析法计算各指标权重,基于改进物元法确定各指标的风险等级,然后将两者向量相乘,以最大隶属度原则确定整体钢平台顶升模架体系的安全风险等级;最后,将所建立的基于层次分析法(Analytic Hierarchy Process, AHP)-改进物元法的安全风险评估模型应用到某超高层工程实例中,并将评估结果与实际施工情况对比分析。研究表明,该评估模型的计算结果合理且准确可靠,可为超高层整体钢平台顶升模架体系的安全管理提供参考。

成捆圆钢端面点云处理与标牌焊接点定位方法研究

为了实现标牌焊接机器人作业准确定位,提出了一种成捆圆钢端面点云处理及焊接点定位方法。首先,在搜索规则、参数调整等方面对传统点云数据滤波方法进行了改进;其次,提出了融合欧式聚类、AABB(axis-aligned bounding box)算法和RKNN(reverse K-nearest neighbor)搜索算法的点云分割算法;再次,考虑焊牌要求制定了焊接点位选取策略,通过法向量估计进行点云姿态校正,采用RANSAC算法对选定圆钢端面点云进行拟合,得到焊接中心点位;最后,进行了焊牌实验。结果表明:该方法有效去除了无关点云的影响,缩短了滤波时间,大大减少了点云数量,有效地对粘连点云进行分割,得到了每根圆钢端面点云,确定了满足焊牌条件的圆钢,并准确得到了焊接点的坐标;焊牌实验表明,相对定位误差小于8%,满足实际生产需求。所提方法有利于提高焊牌机器人系统的焊牌定位准确度和工作效率,可为类似工业机器人系统定位提供参考。

土石坝运行安全评价的改进组合赋权-云模型

针对土石坝运行安全评价中指标间相互影响、主客观权重赋值不够合理以及隶属区间模糊性等问题,提出了一种土石坝运行安全评价的改进组合赋权-云模型。以运行期土石坝为对象,构建了土石坝安全评价指标体系,分别采用G1法和改进熵权法对评价指标进行主客观赋权,融合博弈论思想求解最优权重组合系数,并引入云模型理论降低评价过程中隶属区间的模糊性。对某土石坝安全状态进行评价并与两种传统组合赋权法进行了对比,结果表明,3种评价方法的评价结果相近且与实际情况相符,但改进组合赋权-云模型考虑了评价指标间的关联性,运用博弈论思想使主客观权重赋值更加合理,能更客观地反映土石坝的真实运行状态。