CONSTRUCTION OF OPTIMAL BLOCKING SCHEMES FOR ROBUST PARAMETER DESIGNS

Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the correspondence relation between fractional factorial RPDs and the blocking schemes for full factorial RPDs. In addition, we provide a construction of optimal blocking schemes that make all main effects and control-by-noise two-factor interactions estimable.

The Method for Optimum Design of Water Rocket Flight Stability Performance Conditions Using CAE with T Method and Robust Parameter Design

A water rocket is a rocket system that obtains thrust by injecting water with compressed air of up to about 8 atmospheres. It is usually manufactured using a pressure-resistant PET bottle. The mechanical elements and principles contained in the water rocket have much in common with the actual small rocket system, and are suitable as educational and research teaching materials in the field of mechanics. Especially in the field of disaster prevention and mitigation, the use of water rockets is being researched and developed as a rescue tool in the event of a flood or earthquake as a disaster countermeasure. However, since the water rocket is a flying object based on the mechanical principle, it is important to ensure the accuracy and stability of the flight path. In this paper, a mechanical simulator is developed with a numerical calculation program based on the mechanical consideration of water rocket flight performance. In addition, the correlation between the flight distance obtained in the simulation and the estimated flight distance is analyzed by applying a multivariate analysis method and verifying the validity of the flight distance calculated from the result. Based on the verification results, we will apply a statistical optimization method to approach the optimization of flight stability performance conditions for water rockets.

A new Rsslor hyperchaotic system and its realization with systematic circuit parameter design

Based on two modified Rosslor hyperchaotic systems, which are derived from the chaotic Rosslor system by introducing a state feedback controller, this paper proposes a new switched Rosslor hyperchaotic system. The switched system contains two different hyperchaotic systems and can change its behaviour continuously from one to another via a switching function. On the other hand, it presents a systematic method for designing the circuit of realizing the proposed hyperchaotic system. In this design, circuit state equations are written in normalized dimensionless form by rescaling the time variable. Furthermore, an analogous circuit is designed by using the proposed method and built for verifying the new hyperchaos and the design method. Experimental results show a good agreement between numerical simulations and experimental results.

拮抗细菌DNA的CpG-N ODN筛选

目的在抑制性CpG寡核苷酸(CpG-NODN)分子设计的基础上,选择部分序列加以合成并对其生物学活性进行鉴定,筛选出能够拮抗细菌DNA的CpG-NODN。方法对合成的10条CpGODN进行生物学活性的初筛和复筛,观察其自身的刺激性及其对CpG-SODN诱导的TNF-α释放的抑制作用。使用RNAstructureversion3.71预测CpGODN的二级结构及自由能,根据10条CpGODN构效关系分析结果,对CpG-NODN分子进行再设计,并从中选择11个序列进行生物活性的筛选。结果首次合成的10条CpGODN仅1条是对细菌DNA拮抗作用较弱的CpG-NODN。通过对其构效关系进行分析,推测CpGODN的生物活性可能与自由能相关。在此基础上对CpG-NODN分子进行了再设计,合成的11条CpGODN中有5条是拮抗作用较强的CpG-NODN。结论获得了6条CpG-NODN。CpGODN的生物活性可能与自由能密切相关。

Enumeration of Strength Three Orthogonal Arrays and Their Implementation in Parameter Design

This paper describes the construction and enumeration of mixed orthogonal arrays (MOA) to produce optimal experimental designs. A MOA is a multiset whose rows are the different combinations of factor levels, discrete values of the variable under study, having very well defined features such as symmetry and strength three (all main interactions are taken in consideration). The applied methodology blends the fields of combinatorics and group theory by applying the ideas of orbits, stabilizers and isomorphisms to array generation and enumeration. Integer linear programming was used in order to exploit the symmetry property of the arrays under study. The backtrack search algorithm was used to find suitable arrays in the underlying space of possible solutions. To test the performance of the MOAs, an engineered system was used as a case study within the stage of parameter design. The analysis showed how the MOAs were capable of meeting the fundamental engineering design axioms and principles, creating optimal experimental designs within the desired context.

基于CPG的仿生机器鳕鱼运动控制研究

针对仿生机器鱼运动控制中的鲁棒性问题,以胸/尾鳍协同推进的仿生机器鳕鱼为研究对象,基于Hopf振荡器建立各自由度的CPG控制器,并运用双向邻近耦合方法构建CPG控制网络.通过改变CPG控制器的频率、幅值、相位差以及偏置量等参数,利用仿真和实验研究相结合的方法,确定机器鱼直游、转弯、倒游等基本行为的条件.仿真与实验结果表明,在此CPG网络控制下,机器鱼在不同游动行为或同一游动行为加减速过程中游动状态均能实现平滑过渡,验证了所建CPG网络的鲁棒性.

一种基于CPG的两足机器人步态生成方法

提出一种基于中枢模式发生器(central pattern generator,CPG)的双足机器人步态生成方法。应用Matsuoka振荡器设计了CPG控制器,其输出控制踝关节角度,膝关节和髋关节角度通过轨迹规划得到。通过将CPG输出与"引导曲线"叠加,实现了机器人的连续稳定行走。该方法避免了CPG繁杂的参数优化过程,是CPG应用的一大进步。MATLAB仿真结果证明了所提方法的可行性。

基于遗传算法的蛇形机器人CPG模型参数优化

针对蛇形机器人采用的循环抑制CPG模型,为解决CPG控制模型中参数整定效率低、不稳定的问题,阐述基于CPG模型的蛇形搜救机器人控制系统总体方案的设计,提出一种基于遗传算法的CPG控制模型参数优化方法,实现链式CPG网络的节律输出。仿真实现蛇形搜救机器人各关节控制信号的有效输出,仿真结果表明,该方法具有高效、准确、稳定等优点,可有效应用于蛇形搜救机器人的步态控制。

基于PSO蛇形机器人CPG控制模型参数的优化

针对蛇形机器人链式CPG(central pattern generator)复杂模型,提出了采用粒子群算法(particle swarm optimization)优化CPG控制模型参数,用来解决CPG参数整定效率低、效果不理想的问题,然后结合Webots机器人仿真软件,实现了PSO算法优化蛇形机器人CPG控制模型参数。最后利用Webots仿真软件,通过实验仿真与遗传算法的结果相对比,证实了PSO算法的优越性,为蛇形机器人的运动步态转换提供好的基础。

印记基因H19和SNRPN CpG位点甲基化状态与精液参数的关联研究

目的:分析印记基因H19和SNRPN印记控制区的各Cp G位点甲基化状态与男性精液参数的关联。方法:选取2014年4至9月于空军总医院男科就诊的符合纳入排除标准的205例男性为研究对象,采用焦磷酸测序法定量分析H19和SNRPN基因的各Cp G位点的甲基化状态,采用典型相关分析印记基因H19和SNRPN的各Cp G位点的甲基化水平与精液参数两组变量的整体相关性。结果:H19基因的Cp G2和Cp G3甲基化水平与精子密度和精子活动力的相关性具统计学意义;SNRPN基因的Cp G5、Cp G6、Cp G7甲基化水平与精子正常形态率的相关性具统计学意义。结论:印记基因H19和SNRPN印记控制区特定Cp G位点甲基化状态与精液参数有关联。

基于CPG控制模型的仿生鳐鱼运动系统研究

随着现代科技的不断进步以及陆上资源的有限性,人们对于水下探测的需求日益增加,用于水下资源勘探以及水质监测的水下机器人也越来越多。近年来,仿生鱼水下机器人以其高机动、低扰动、运动灵活等优点成为人们主要的研究对象。仿生鳐鱼水下机器人采用独特的扑翼滑翔式推进运动方式,不仅能大大提高运动时的机动性,还能在滑翔推进的过程中节省能耗,从而延长水下作业的时间。基于此,笔者提出一种基于中枢模式发生器(Central Pattern Generator,CPG)运动控制模型的仿生鳐鱼水下机器人的运动控制系统。该系统可以根据不同的游动姿态分析耦合关系及连接权重,结合强化学习进一步调整参数,从而提高仿生鱼的机动性能。

PROCESSING PARAMETER OPTIMIZATION OF FDM BASED ON ROBUST DESIGN

The influence of processing parameters on the precision of parts fabricated by fused deposition modeling （FDM） technology is studied based on a series of performed experiments. Processing parameters of FDM in terms of wire-width compensation, extrusion velocity, filing velocity, and layer thickness are chosen as the control fac- tors. Robust design analysis and multi-index fuzzy comprehensive assessment method are used to obtain the opti- mal parameters. Results show that the influencing degrees of these four factors on the precision of as-processed parts are different. The optimizations of individual parameters and their combined effects are of the same impor- tance for a high precision manufacturing.

A global solution for robust parameter design of aeronautical electrical apparatus based on interactions analysis and polynomial fitting

Robust Parameter Design(RPD) has been widely applied for improving quality and reliability of products.One of the key drawbacks of applying RPD using Taguchi method is that the stable factors may not be independent of the adjustment factors, resulting in unsatisfactory design.Moreover, the Taguchi method cannot guarantee global optimality since the levels set in the experiment are usually discrete to ensure orthogonal design.In this paper, robust solutions of the stable factors are obtained via a nonlinear model based on polynomial fitting;while the adjustment factors are obtained via interactions analysis so that they are independent of the stable factors.In particular, the values of the adjustment factors are determined by output offset compensation so as to achieve robustness of the design scheme.An example on the design of an aeronautical electrical apparatus is presented to illustrate the procedure.The results show that the proposed method can take full advantage of the nonlinearity in the response and achieve the desired outcome.

Review of Design of Process Parameters for Squeeze Casting

Squeeze casting(SC)is an advanced net manufacturing process with many advantages for which the quality and properties of the manufactured parts depend strongly on the process parameters.Unfortunately,a universal efficient method for the determination of optimal process parameters is still unavailable.In view of the shortcomings and development needs of the current research methods for the setting of SC process parameters,by consulting and analyzing the recent research literature on SC process parameters and using the CiteSpace literature analysis software,manual reading and statistical analysis,the current state and characteristics of the research methods used for the determination of SC process parameters are summarized.The literature data show that the number of pub-lications in the literature related to the design of SC process parameters generally trends upward albeit with signifi-cant fluctuations.Analysis of the research focus shows that both“mechanical properties”and“microstructure”are the two main subjects in the studies of SC process parameters.With regard to materials,aluminum alloys have been extensively studied.Five methods have been used to obtain SC process parameters:Physical experiments,numeri-cal simulation,modeling optimization,formula calculation,and the use of empirical values.Physical experiments are the main research methods.The main methods for designing SC process parameters are divided into three categories:Fully experimental methods,optimization methods that involve modeling based on experimental data,and theoreti-cal calculation methods that involve establishing an analytical formula.The research characteristics and shortcomings of each method were analyzed.Numerical simulations and model-based optimization have become the new required methods.Considering the development needs and data-driven trends of the SC process,suggestions for the develop-ment of SC process parameter research have been proposed.

Reliability-based Robust Optimization Design of Automobile Components with Non-normal Distribution Parameters

In the reliability designing procedure of the vehicle components, when the distribution styles of the random variables are unknown or non-normal distribution, the result evaluated contains great error or even is wrong if the reliability value R is larger than 1 by using the existent method, in which case the formula is necessary to be revised. This is obviously inconvenient for programming. Combining reliability-based optimization theory, robust designing method and reliability based sensitivity analysis, a new method for reliability robust designing is proposed. Therefore the influence level of the designing parameters’ changing to the reliability of vehicle components can be obtained. The reliability sensitivity with respect to design parameters is viewed as a sub-objective function in the multi-objective optimization problem satisfying reliability constraints. Given the first four moments of basic random variables, a fourth-moment technique and the proposed optimization procedure can obtain reliability-based robust design of automobile components with non-normal distribution parameters accurately and quickly. By using the proposed method, the distribution style of the random parameters is relaxed. Therefore it is much closer to the actual reliability problems. The numerical examples indicate the following: (1) The reliability value obtained by the robust method proposed increases (】0.04%) comparing to the value obtained by the ordinary optimization algorithm; (2) The absolute value of reliability-based sensitivity decreases (】0.01%), and the robustness of the products’ quality is improved accordingly. Utilizing the reliability-based optimization and robust design method in the reliability designing procedure reduces the manufacture cost and provides the theoretical basis for the reliability and robust design of the vehicle components.

Parameter design for a vibration absorber with time-delayed feedback control

Traditional passive vibration absorbers are effective only when their natural frequencies are close to those of the excitations. To solve this problem, a vibration absorber with time-delayed feedback control is proposed to suppress vibration of the primary system under excitation with changing frequency. Firstly, the mechanical model of the delay coupled system is established. Then, the displacement transfer ratio of the system is obtained. The stability of the system is analyzed since delay may result in destabilization. Next, in order to design the control parameters, the vibration absorption performances of the proposed time-delayed vibration absorber are studied. The vibration absorption region is shown. The results show that time-delayed feedback control is able to change the response of the system. The effective vibration absorption frequency band is adjustable by tuning the control gain and time delay. The effective frequency band can be widened when choosing appropriate control parameters. The vibration absorption performances can be greatly improved by the time-delayed absorber. In addition, the optimum control parameters are obtained. Finally, the experimental prototype is constructed. Several tests with different control parameters are taken. The experimental and analytical results match quite well.

Optimal Design of Bicycle Frame Parameters Considering Biomechanics

With the development of technology and the change of market demands,the trend in middle and high grade bicycle manufacturing is developed toward small-volume,multi-species,and customer-oriented production.Therefore,human element should be fully considered in design so that the bicycle has the best cycling performance for the specific rider.Currently,customized design is difficult to achieve since feature parameters of the rider are not included in the design.The design of bicycle frame is the most important in bicycle design.The relative positions among the saddle,handlebar and central axis are defined as the bicycle three-pivot,they are the main parameters in bicycle frame design.In conventional bicycle design,frame parameters are merely relevant to bicycle types.On the basis of the principles of biomechanics and ergonomics knowledge,this paper presents a design method for bicycle three-pivot considering feature parameters of the rider by dynamic simulation.Firstly,a dynamic model of rider-bicycle system is built for a special rider,and a serial of simulation experiments is designed by uniform test method.Then,a mathematical model is built between the three-pivot position and the square of lower limb muscle stress by using simulation and regression analysis of the rider-bicycle system.The optimal three-pivot position parameters are obtained by setting the minimal of the square of the lower limb muscle stress as the objective.Therefore,the optimal parameters are gained for the specific rider.Finally,various results are gained for different riders based on the same design process.The function between feature parameters of the rider and the optimum three-pivot position parameters is built by regression.Bicycle design considering biomechanics can be divided into three main steps：calculating the three-pivot position,designing the geometrical structure of the bicycle frame and analyzing frame strength,and selecting appropriate parts and assembling the bicycle.Bicycle design considering biomechanics changes the conventional bicycle design and realizes customized design by considering human element in the design process.

Modeling Approach and Analysis of the Structural Parameters of an Inductively Coupled Plasma Etcher Based on a Regression Orthogonal Design

The geometry of an inductively coupled plasma （ICP） etcher is usually considered to be an important factor for determining both plasma and process uniformity over a large wafer. During the past few decades, these parameters were determined by the ＂trial and error＂ method, resulting in wastes of time and funds. In this paper, a new approach of regression orthogonal design with plasma simulation experiments is proposed to investigate the sensitivity of the structural parameters on the uniformity of plasma characteristics. The tool for simulating plasma is CFD-ACE＋, which is commercial multi-physical modeling software that has been proven to be accurate for plasma simulation. The simulated experimental results are analyzed to get a regression equation on three structural parameters. Through this equation, engineers can compute the uniformity of the electron number density rapidly without modeling by CFD-ACE＋. An optimization performed at the end produces good results.

Application of Uniform Experimental Design in Optimizing Excitation Parameters for Magnetic Frequency Mixing Measurements

Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensive model is established for evaluating the e ect of magnetic frequency mixing.A polynomial is selected as the regression function to express explicitly the correlation between the excitation parameters and the frequency-mixing e ect.The excitation parameters were then optimized using genetic algorithm.Magnetic frequency mixing experiments were conducted to measure the surface hardness of some ferromagnetic materials.Frequency mixing is further enhanced under the optimal settings,resulting in an improvement in the measurement sensitivity.The results of this study support the application of the magnetic frequency mixing technique in non-destructive testing.

Application Strategies of Modular Design in Assembled Teaching Buildings

As an efficient,environmentally friendly,energy-saving construction method,assembled buildings are now widely used in campus building construction.Modular design thinking is system-based design thinking,and its application to the design of an assembled teaching building project will comprehensively improve the rationality of the teaching building and component design.The paper focuses on the application of modular design thinking in assembled teaching building design,aiming to provide references for China’s architectural design units,giving full play to the advantages of modular design thinking in future teaching building design projects,and enhancing the level of design,for the construction of the teaching building and the basis of the technical guarantee.