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Finite element methods (FEM) are commonly used to analyze the behavior of various dynamic systems. Several model updating techniques are available that can be used for linear or nonlinear dynamic systems and help reduce discrepancies between characteristics obtained from the FE models and their experimental counterparts. Linear model updating techniques employ eigen solutions or the frequency response functions (FRF) to reduce errors between the discretized mass [M], damping [C], and stiffness [K] terms or FRF terms directly. However, model updating of structures exhibiting nonlinear behavior is seldom straightforward and requires special consideration of various terms contributing to the nonlinear responses when modeling the system. This paper investigates a hybrid static and dynamic model updating technique for structures exhibiting geometric nonlinearity. The static model updating minimizes errors in stiffness modeling and the dynamic model updating minimizes errors in modeling non-stiffness terms of the FE model.

Nickel slag can be recycled as one of excellent secondary sources due to valuable iron resource. A static model of recycling nickel slag by aluminum dross was established based on material balance and non-isothermal thermodynamic calculations. Discussions had been carried out under different basicities of the modified slags and the reduction degree of ‘FeO,’ and the results showed that the dosage of nickel slag, aluminum dross, and modifier is 55.60%, 28.82%, and 15.58%, respectively, at the basicity of modified slag of 1.0. The non-isothermal thermodynamic model indicated that an increment of slag temperature from 114.3 to 430.2 K could be obtained with the reduction process, which not only signified the superiority of aluminothermy, but also laid a foundation for the industrial practice.

Thanks to new technologies, it is possible to make an automatic robotic treatment of plants for the mildew in greenhouses. The optimization of the scheduling of this robotic treatment presents a real challenge due to the continue evolution of disease level. The conventional optimization methods can not provide an accurate scheduling capable to eliminate the disease from the greenhouse. This paper proposes a solution to provide a dynamic scheduling problem of evolutionary tasks in horticulture. We first developed a genetic algorithm (GA) for a static model. Then we improved it for the dynamic case where a dynamic genetic algorithm (DGA) based on the prediction of the task amount is developed. To test the performance of the designed algorithms, especially for the dynamic case, we integrated our algorithms in a simulator.

This paper presents a method for type synthesis of gripper mechanisms using Baranov chains and Davies’ method. First, a novel concept called Reshetov virtual joints, i.e. joints without freedoms, is introduced and applied to create a seed mechanism with redundant constraints. Next, Davies’ method is used to create a matrix representation of the static model of the seed mechanism. The number of constraints is analysed, and redundant constraints of the seed mechanism are discussed. Based on the number of redundant constraints, a removal of a set of columns from the matrix created from Davies’ method is applied and discussed. New gripper mechanisms, derived from the seed mechanisms, can thus be created by removing a set of columns from the static model matrix. As a result, new gripper mechanisms based on Baranov chains, are obtained.

Accuracy of the workpiece geometry is negatively affected by several sources of errors during milling operation, the most important one is tool deflection which will result in the deviation of the tool path and cutting force is the most significant factor responsible for this error.

This chapter discusses how the test drive method alleviates the disruptions that arise when businesses implement critical decisions that produce major internal changes. Section 13.1 offers a primer on organizational change. Section 13.2 presents a static conceptual model for responding effectively to imminent change. Section 13.3 describes our solution for test driving decisions to enable smooth change, which extends and animates the static model. Section 13.4 reviews test drive results from a pilot project to craft a change strategy for a highly disruptive decision to switch compensation methods. Section 13.5 summarizes the benefits of using a test drive model to help design, test, and execute change strategies. A video is available that explains and demonstrates this test drive solution.

This chapter illustrates the efficiency of parametric control based on the dynamic computable general equilibrium (CGE) model that was developed from the static model Globe 1 [43].

Supplier selection problem in dynamic context faces different challenges, such as fuzzy information, missing evaluation values, alternatives, attributes, the importance of attributes may vary with time, and the inconsistency of rankings caused by high static values and low dynamic values of newly added alternatives. Firstly, interval bipolar 2-tuple linguistic terms are used to deal with the problem of fuzzy information and missing evaluation values. Secondly, a linear programming (LP) model is used to dynamically allocate attribute weights to solve the problem that alternatives, attributes, and the importance of attributes may vary with time. Furthermore, dynamic time weights are proposed to solve the inconsistency problem of rankings caused by high static values and low dynamic values of newly added alternatives. Finally, a practical supplier selection case to illustrate the efficiency and feasibility of the proposed model is presented together with a comparison against the static model.

Applications of optimization methods to production and inventory problems date back at least to the classical EOQ (Economic Order Quantity) model or the lot size formula of Harris (1913) . The EOQ is essentially a static model in the sense that the demand is constant and only a stationary solution is sought. A dynamic version of the lot size model was analyzed by Wagner and Whitin (1958) . The solution methodology used there was dynamic programming.

Quality of Service (QoS) is an important factor which should be considered in service matching. There are two problems in most existing solutions. Firstly, most QoS models are static model described by determinate values or probability distributions, ignoring the impact of time factor. However, most QoS attributes are time-dependent, such as response time and reliability. Secondly, the service selection criteria of most QoS-driven service matching algorithms are based on service performance, but user requirements and the load of services are not considered. In this paper, we propose a Time-Segmented QoS Model (TSQM) to dynamically model QoS. Based on this model, a Service Matching algorithm based user QoS request and Priority (QPSM) is proposed. The priority of user requests is used to control the load of the services. Simulation results show that the algorithm can achieve a higher response rate and a better effect of load balancing.

In this paper, we created a conceptual model UML (unified modelling language) showing interactions between animals, mosquitoes, environment, and climate factors. The UML static model was used to build an agent-based model that helps to study the impact of rainfall variability on the number of infected hosts after the outbreak of Rift valley fever. Several simulations were done on the multi-agent CORMAS platform. The different results showed continued growth in infections during the rainy season. A sensitivity analysis taking into account the delayed rains and dry spells have allowed us to know a clear vision about the rate of infected animals due to the rainfall variability. This work defines a framework for studying the impact of climatic changes on vector-borne diseases.

This paper shows how different working modes in a symmetrical 3RRR planar parallel manipulator can influence its maximum isotropic force capability maps. Herein, a new method to obtain analytically the maximum isotropic force with a prescribed moment is proposed. The proposed method is obtained from a general static model of the studied manipulator obtained by employing the screw theory and the Davies method as primary mathematical tools. Finally, some maximum isotropic force capability maps are obtained for different working modes in the studied manipulator in order to analyse their influence.

In this paper, a model is presented for the elasto-static problem of planar point mass robots suspended by m-cables . In particular, each cable configuration is described by an elastic catenary and static equations and compatibility conditions for the system are given, thus the 2m force reaction unknowns can be evaluated. The proposed formulation has been used to solve the direct problem and it is suitable for investigating the influence of elastic catenary on the end-effector exact positioning. The model allows evaluating the relation between end-effector position and the involvement of each cable in sustaining the payload.

The paper presents a method of control of an oxygen flow in the PEM fuel cell without recirculation. The proposed procedure of finding an optimal value of the oxygen flow basis on comparing a current voltage of the cell with a reference one obtained from a static model of the PEM fuel cell. Simulation results show that such value of the flow is obtained for a limited number of steps. It allows to reduce the oxygen usage assuring safe operation of the fuel cell.

In today’s competitive business environment, it has become increasingly important to reduce manufacturing and raw materials costs. For this purpose, an innovative process of design and manufacturing railway axles is developed. It is based on forging hollow axle which allows a significant reduction in steel consumption. In this work, we tried to analyse how these modifications induced by this new process and design impact on the residual stress field. For this particular study, a numerical chain has been developed going from the simulation of the hot upsetting manufacturing process of the railway axle with the explicit method, to the analysis of the cutting and the press fitting assembly operation. This study consists in modelling the forging process with the dynamic FEM in order to take into account the dynamic phenomena and predict the residual stress field and the initial plastic strain. Then the evaluation of the cutting operation of the upper axle surface and finally the simulation of assembling the wheel on the axle with a static model, to better estimate the stress relaxation and redistribution.

Recently, a static model of the knee featuring a spherical approximation of the contact surfaces has been defined by a sequential approach, in order to generalize a kinematic model of the joint passive motion. The aim of this study is to define a more sophisticated static knee model with articular surfaces which accurately reproduce the anatomical ones. The motion of the new model is compared, under several loading conditions, with the motion of the knee when the same loads are applied and with the motion of the previous static model. Although some improvements could be achieved by a proper optimization of the model parameters, the model is able to replicate the behavior of the human knee under both passive and loaded conditions.

Converter steelmaking by using limestone instead of lime is studied in this paper. The theoretical feasibility of using limestone is analyzed. A partition model for carbon dioxide reacting with [C], [Si], [Mn] and [Fe] is established based on thermodynamic analysis. According to the mass and heat balance calculation, materials consumptions under different limestone substituting proportions are obtained. The results show that limestone can be used in converter steelmaking and the largest limestone substitution proportion is about 70%. With the increase of the limestone substitution, hot metal consumption, CO percentage and volume, CO2 output and the converter gas volume increase, while scrap consumption, CO2 percentage and the steelmaking cost decrease.