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AbstractThe United Nations aim to perform a transition toward a sustainable environment where people can live by decoupling economic growth from resource use. Through the definition of the Agenda 2030 and the corresponding sustainable development goals, this transition asks for a lower dependence on non-renewable resources and for the use of recycled materials in a finite term perspective. In this respect, we provide an optimal control model which searches for an efficient allocation of labor between non-recycling and recycling sectors exploiting a given non-renewable resource. The optimization process is carried out over a finite time horizon in accordance with the need of rapidly achieving the targets imposed by the ecological transition. By employing the classical tools of optimal control theory, a complete theoretical analysis of the model well-posedness is developed under the assumption of linear production in both sectors. The approach is applied in order to simulate a hypothetical test case.

Objective: The objective was to study the performance of a manual tracking task with system flexibility and time delays in the input channel and to examine the effects of input shaping the human operator's commands. Background: It has long been known that low-frequency, lightly damped vibration hinders performance of a manually controlled system. Recently, input shaping has been shown to improve the performance of such systems in a compensatory-display tracking task. It is unknown if similar improvements are seen with pursuit-display tasks, or how the improvement changes when time delays are added to the system. Method: A total of 18 novice participants performed a pursuit-view tracking experiment with a spring-centered joystick. Controlled elements included an integrator, an integrator with a lightly damped flexible mode, and an input-shaped integrator with a flexible mode. The input to these controlled elements was delayed between 0 and 1 s. Tracking performance was quantified by root mean square tracking error, and subjective difficulty was quantified by ratings on a Cooper–Harper scale. Results: Performance was best with the undelayed integrator. Both time delay and flexibility degraded performance. Input shaping improved control of the flexible element, with a diminishing benefit as the time delay increased. Tracking error and subjective rating were significantly related. Some operators used a pulsive control strategy. Conclusion: Input shaping can improve the performance of a manually controlled system with flexibility, even when time delays are present. Application: This study is useful to designers of human-controlled systems, especially those with problematic flexibility and/or time delays.

This paper was published in SAE Technical Papers and the definitive published version is available at https://doi.org/10.4271/2017-01-0600. ; This paper surveys publications on automotive powertrain control, relating to modern GTDI (Gasoline Turbocharged Direct Injection) engines. The requirements for gasoline engines are optimising the airpath but future legislation suggests not only a finely controlled airpath but also some level of electrification. Fundamentals of controls modelling are revisited and advancements are highlighted. In particular, a modern GTDI airpath is presented based on basic building blocks (volumes, turbocharger, throttle, valves and variable cam timing or VCT) with an example of a system interaction, based on boost pressure and lambda control. Further, an advanced airpath could be considered with applications to downsizing and fuel economy. A further electrification step is reviewed which involves interactions with the airpath and requires a robust energy management strategy. Examples are taken of energy recovery and e-machine placement. Control-oriented models of gasoline engines are reviewed, and challenging control problems for conventional engines and hybrid vehicle powertrains are discussed, in particular relating to consideration of the complex interactions. A systems approach is needed to understand the attribute trade-off, with fuel consumption, emissions, as well as energy storage on a particular drive cycle. This necessitates an optimisation methodology and appropriate problem formulation of objective, states and constraints. A discussion of optimisation techniques is considered. Finally, a comprehensive list of references is provided.

Speed squirrel cage motor control is an area of research that has been in evidence for some time. In this paper, a nonlinear controller is presented for the squirrel cage motor drives, based on a combination between input-output feedback linearization control (IOLC) technique and sliding mode control (SMC) to create a new control which is sliding input-output linearization (SIOLC) control of squirrel cage motors, where the sliding mode control is used for controlling the speed of squirrel cage motor and the input-output linearization control applied for two input witch are flux and current. To test the robustness and performance of sliding input-output linearization control (SIOLC) we created a variety of internal and external parameters of the motor. The simulation results are done using Matlab/Simulink, which shows the robustness of the sliding input-output linearization control of squirrel cage motor responses.

This article belongs to the Section Physical Sensors. ; Many of the current research works are focused on the development of different control systems for commercial vehicles in order to reduce the incidence of risky driving situations, while also improving stability and comfort. Some works are focused on developing low-cost embedded systems with enough accuracy, reliability, and processing time. Previous research works have analyzed the integration of low-cost sensors in vehicles. These works demonstrated the feasibility of using these systems, although they indicate that this type of low-cost kit could present relevant delays and noise that must be compensated to improve the performance of the device. For this purpose, it is necessary design controllers for systems with input and output delays. The novelty of this work is the development of an LMI-Based H∞ output-feedback controller that takes into account the effect of delays in the network, both on the sensor side and the actuator side, on RSC (Roll Stability Control) systems. The controller is based on an active suspension with input and output delays, where the anti-roll moment is used as a control input and the roll rate as measured data, both with delays. This controller was compared with a controller system with a no-delay consideration that was experiencing similar delays. The comparison was made through simulation tests with a validated vehicle on the TruckSim® software. ; This work was supported by the FEDER/Ministry of Science and Innovation-Agencia Estatal de Investigacion (AEI) of the Government of Spain through the project [RTI2018-095143-B-C21].

Abstract
The present study compared the effects of reading input flooding and listening input flooding techniques on the accuracy and complexity of Iranian EFL learners' speaking skill. Participants were 66 homogeneous intermediate EFL learners who were randomly divided into three groups of 22: Reading input flooding group, listening input flooding group, and control group. The reading flooded input group was exposed to the numerous examples of the target structures through reading. In the same phase, the listening group was given relatively the same task, through listening. The participants' monologues in the posttest were separately recorded, and later transcribed and coded in terms of accuracy and complexity through Bygate's (2001) standard coding system. The results of ANCOVA indicated the outperformance of reading input flooding group. The study also supported the trade-off effects (Skehan, 1998, 2009) between accuracy and complexity.

"The upcoming Economic Partnership Agreements (EPAs) between the European Union and African, Caribbean and Pacific (ACP) countries and regions are extremely challenging. Conceived as a follow-up to the non-reciprocal trade preferences granted to the ACP since 1975, the aim of the EPAs is sustainable development and poverty reduction through the establishment of a Free Trade Area. Many challenges and opportunities arise from this ambitious trade and development partnership between some of the world's poorest and richest countries. Throughout the negotiations, several stakeholders have expressed concerns about the possible negative effects in ACP countries that risk jeopardizing the developmental impacts of EPAs. The ambition, as well as the uncertainties around EPAs make a results-oriented monitoring of the agreements imperative. This study, commissioned by the German Ministry for Economic Cooperation and Development, addresses the possible goals of EPA monitoring, drawing conclusions on what broad areas need to be monitored, which principles should be followed and which stakeholders involved. The study then outlines the challenges involved in implementing a results-oriented monitoring system: which steps need to be taken, how best to derive indicators, which characteristics the latter should have and how they may be identified. The study also presents a number of recommendations on how to ensure that monitoring is given due consideration in the EPA legal texts." (author's abstract)