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Presents numerical algorithms which easily solve both optimal distributed and optimal boundary control problems in a space‐time domain. Analyses two simple cases of continuous systems. These are the vibrating string and the axially vibrating rod. Using finite difference recurrence schemes, gives numerical results which compare the behaviour of the controlled and uncontrolled systems. Compares the results for special cases in which analytical solutions are obtainable are compared with the results using the general numerical schemes.

The optimal thickness distribution of a two‐span continuous beam is determined with the objectives of minimizing the maximum stress, maximizing the fundamental frequency and frequency separation between adjacent frequencies. The self‐weight of the beam is included in the computations. The multiobjective design problem is solved by using the concept of Pareto optimality. The beam thickness is approximated by constant splines. The stress distribution and the frequencies are determined by the finite element method. The optimization of the beam is carried out by the feasible direction method and by employing a quadratic approximation of the thickness function. Numerical results are given for two‐objective design problems. Optimal trade‐off curves, thickness distributions and stress distributions of optimally designed beams are presented in graphical form. The effects of self‐weight and different design objectives on the thickness distribution are investigated.

Distributed control is an effective method for controlling and suppressing excessive vibrations of continuous systems. Optimal distributed control for a plate problem is solved utilizing a maximum principle after the introduction of a quadratic index of performance in terms of displacement, velocity and a control force as well as an adjoint variable. The problem is reduced to solving a system of partial differential equations for the state variable and the adjoint variable subjected to boundary, initial and terminal conditions. A numerical algorithm is presented to solve the optimal distributed control problem in the space‐time domain which reduces the computational effort required to solve the initial‐terminal‐boundary value problem. Results obtained for a simply supported, rectangular, thin plate are also presented.

This paper aims to present a summary of the performance measurement and evaluation plan of the Wyoming connected vehicle (CV) Pilot Deployment Program (WYDOT Pilot).

This paper identified 21 specific performance measures as well as approaches to measure the benefits of the WYDOT Pilot. An overview of the expected challenges that might introduce confounding factors to the evaluation effort was outlined in the performance management plan to guide the collection of system performance data.

This paper presented the data collection approaches and analytical methods that have been established for the real-life deployment of the WYDOT CV applications. Five methodologies for assessing 21 specific performance measures contained within eight performance categories for the operational and safety-related aspects. Analyses were conducted on data collected during the baseline period, and pre-deployment conditions were established for 1 performance measures. Additionally, microsimulation modeling was recommended to aid in evaluating the mobility and safety benefits of the WYDOT CV system, particularly when evaluating system performance under various CV penetration rates and/or CV strategies.

The proposed performance evaluation framework can guide other researchers and practitioners identifying the best performance measures and evaluation methodologies when conducting similar research activities.

To the best of the authors’ knowledge, this is the first research that develops performance measures and evaluation plan for low-volume rural freeway CV system under adverse weather conditions. This paper raised some early insights into how CV technology might achieve the goal of improving safety and mobility and has the potential to guide similar research activities conducted by other agencies.

The purpose of this paper is to propose an optimization method by combining artificial immune algorithm and finite element analysis to find the optimal exciting electrode of a piezoceramic plate type ultrasonic motor vibrator.

The artificial immune algorithm is selected as optimizer for its merit of fast convergence to global optimal solution. The finite element analysis is used to calculate the motion trajectory of contact point. The objective function is the work that the vibrator does to rotor. The design variables are the boundaries of exciting electrode on piezoceramic plate vibrator surface.

The calculated results and the experimental results show that using this method, both the position and the size of optimal exciting electrode of this ultrasonic motor can be quickly and accurately determined.

In order to successfully design an ultrasonic motor, both the position and the size of the exciting electrode must be investigated, so as to change more electric energy into mechanical energy. In this paper, an optimization method by combining artificial immune algorithm and finite element analysis is proposed for the exciting location optimization of a piezoceramic plate type ultrasonic motor to obtain large power output.

The purpose of this paper is to make a lean assessment of a chemical analyst training laboratory in a higher education institution and identify the main types of waste on a daily basis and understand the lean maturity of the laboratory and establish priority areas of intervention to make the laboratory leanest.

A single descriptive case study methodology was used to carry out the lean laboratory evaluation. The lean manufacturing waste terminology was adapted to a lean analytical laboratory environment, and a lean waste assessment step-by-step procedure was developed to reach the study goal.

Three types of waste (i.e. transport, waiting and defects) were the main contributors of the problem. The Pareto analysis results showed that 37.5% of the different types of waste contributed to almost 51.4% of the problems. The case study allowed on diagnosing wastes, understanding the lean maturity in a teaching laboratory setting and priority areas of intervention

Some data collection methods were used, and tools were developed to answer the research questions. A waste measurement instrument was created to evaluate lean waste in a chemical analytical laboratory, and a lean classification scheme was built to understand the lean maturity of the laboratory. The lessons learnt of the lean assessment in a teaching laboratory and the developed tools will be helpful for future research and for practitioners in a teaching chemical analytical laboratory setting.

The number of lean assessment studies in teaching laboratories is not very significant, and this work contributes to overcome this gap illustrating the lean waste assessment foundation with a step-by-step procedure and tools used in a teaching laboratory to perform a lean assessment and identify opportunities for improvement. A generic roadmap to lean laboratory waste assessment and continuous improvement is proposed with the key elements to take into consideration.

The purpose of this paper is to provide a case study on endorsing process improvement in maritime operations by implementing design of experiments on Lean Six Sigma performance responses. It is demonstrated how process efficiency and environmental muda may be dealt with simultaneously in a lean‐and‐green project driven by hardcore Six Sigma tools.

A 16‐run Taguchi‐type orthogonal design was employed to gather data for vessel speed (VS), exhaust gas temperature (EGT) and fuel consumption (FC) as modulated by a total of 15 controlling parameters synchronously. Active dependencies were inferred based on the desirability analysis method on direct process data from a performance log. This log was maintained for a long‐term monitoring during sea voyages of a double skin bulk carrier of 55,000 DWT while in sea service.

A high composite desirability value was achieved eclipsing the 0.90 mark. Values well over the 0.9 level were also obtained for the three examined individual desirability values of VS, EGT and FC. Leading controlling parameters were discovered to be compressor pressure, fuel pump index, slip, governor index and MIP.

A Lean Six Sigma project is carried out to improve performance characteristics in ordinary maritime operations. While the company in the case study outlined in this article no longer relies on periodic inspections to determine machinery conditions, improvement on key process characteristics were nevertheless deemed worthy of ameliorating. Information retrieval from computerized continuous monitoring systems assisted in conducting experimental designs in order to obtain optimal performance. Specifically, the tuning of vessel main engine running mode was examined aiming at increasing the quality levels of output power to the shaft along with a reduction of NOx emissions.

This work adds an interesting paradigm in the critical field of maritime activities for processes in full gear while operating at sea. Maritime operations are an imperative necessity when expediting international trading transactions. It is the first time that such a case study has emanated from a real pilot Lean Six Sigma project which interlaces process efficiency enhancement with concurrent environmental muda reduction.

In this paper, the authors study the nonlinear matrix equation Xp=Q±A(X-1+B)-1AT, that occurs in many applications such as in filtering, network systems, optimal control and control theory.

The authors present some theoretical results for the existence of the solution of this nonlinear matrix equation. Then the authors propose two iterative schemes without inversion to find the solution to the nonlinear matrix equation based on Newton's method and fixed-point iteration. Also the authors show that the proposed iterative schemes converge to the solution of the nonlinear matrix equation, under situations.

The efficiency indices of the proposed schemes are presented, and since the initial guesses of the proposed iterative schemes have a high cost, the authors reduce their cost by changing them. Therefore, compared to the previous scheme, the proposed schemes have superior efficiency indices.

Finally, the accuracy and effectiveness of the proposed schemes in comparison to an existing scheme are demonstrated by various numerical examples. Moreover, as an application, by using the proposed schemes, the authors can get the optimal controller state feedback of $x(t+1) = A x(t) + C v(t)$.

The aim of this study is to determine the effect of the application of the lean methodoloy in the pathology laboratory and to evaluate the results on the turnaround time.

This study was a prospective intervention study formed of the three stages of pre-intervention, determination of problem areas and the application of lean techniques and quality improvement. The study was conducted between February 2019 and August 2020. In the first stage, research was made through interviews, observations, questionnaires and seminars; in the second stage, observations, brain-storming, process flowcharts and fishbone diagram were used; and in the third stage, Kaizen, A3 method and spaghetti diagram were applied.

Following the application of lean techniques, turnaround time in the pathology laboratory was decreased, and the changes made in the working methods and placement of the units in the laboratory were found to have prevented unnecessary steps. The lean method was also determined to have had positive effects on the workplace satisfaction of the laboratory employees and of the physicians working with the laboratory.

The results showed that applying lean techniques could reduce waste and increase participation in processes. This article demonstrates its originality and relevance by proving that the lean techniques can be applied in the hospital laboratory. Actions to improve turnaround time are also crucial for the efficient use of resources.

This paper aims to address a need for improving the structural resilience to multi-hazard threats including fire and progressive collapse caused by the loss of a column.

The focus is on a steel moment frame that uses welded-unreinforced flange-bolted web connections between the beams and columns. A three-dimensional finite element (FE) model was created in ABAQUS with temperature-dependent properties for steel based on the Eurocode. The model was validated against experimental data at ambient and elevated temperature.

The failure mechanisms in the FE model were consistent with experimental observations. Two scenarios were considered: fixed load with increasing temperature (i.e. simulating column failure prior to fire) and fixed temperature with increasing load (i.e. simulating column failure during fire).

A macro element (or component-based) model was also introduced and validated against the FE model and the experimental data, offering the possibility of analyzing large-scale structural systems with reasonable accuracy and improved computational efficiency.