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The ample systems-orientated rhetoric of sustainable tourism has not triggered much practical change because it is directed at the wrong level and the relevance of the discourse eludes local agents in tourism systems. Practical movement towards sustainable tourism hinges on finding tools that can aid practical moves by local tourism enterprises and, as the local contexts vary, a flexible approach

Despite of a crucial role of microclimate inside clothing in thermal comfort, air velocity inside clothing has been hardly reported, ever since Lewis et al (1969) demonstrated that air velocity of the still air layer on the naked human body was 0.25 m/s using colour schlieren cinephotography. This study was aimed to investigate the air velocity of microenvironment inside clothing and the bellows e

Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to rep

Migratory animals provide a multitude of services and disservices-with benefits or costs in the order of billions of dollars annually. Monitoring, quantifying, and forecasting migrations across continents could assist diverse stakeholders in utilizing migrant services, reducing disservices, or mitigating human-wildlife conflicts. Radars are powerful tools for such monitoring as they can assess dir

American political theorist Robert Dahl's 1961 work of political theory exhibits deep levels of creative thinking. When Dahl wrote, the American system of liberal democracy was generally considered to be shaped by a small group of powerful individuals who dominate because they are wealthy and influential. But by connecting the evidence in a new way in Who Governs? Dahl argued convincingly against

A multi-variable PI (proportional integrating) controller is proved to be optimal for an important class of control problems where performance is specified in terms of frequency weighted H-infinity norms. The problem class includes networked systems with a subsystem in each node and control action along each edge. For such systems, the optimal PI controller is decentralized in the sense that contr

This paper develops a novel framework for power system stability analysis, that allows for the decentralised design of inverter based controllers. The method requires that each individual inverter satisfies a standard H∞ design requirement. Critically each requirement depends only on the dynamics of the components and inverters at each individual bus, and the aggregate susceptance of the transmiss

Modeling of robot motion as dynamical movement primitives (DMPs) has becomean important framework within robot learning and control. The ability of DMPs to adapt online with respect to the surroundings, e.g., to moving targets, has been used and developed by several researchers. In this work, a method for handling perturbations during execution of DMPs on robots was developed. Two-degree-of-freedo

We show how to minimize the energy required to build up the electromagnetic field in radio-frequency cavities, which will allow power savings for pulsed particle accelerators. By formulating an optimal control problem for a first-order system we obtain a solution on state-feedback form. We numerically compare the optimal solution to previous approaches.

This paper presents an algorithm for Model Predictive Control of SISO systems. Based on a quadratic objective in addition to (hard) input constraints it features soft upper as well as lower constraints on the output and an input rate-of-change penalty term. It keeps the deterministic and stochastic model parts separate. The controller is designed based on the deterministic model, while the Kalman

The fast-increasing demand and relatively slow growth of infrastructure capacity are providing a strong motivation for research in real-time urban traffic controls that make the best use of novel sensing in order to increase efficiency and resilience of the transportation system. In our contribution, we focus on a class of dynamic feedback traffic signal control policies that are based on a genera

This paper studies the properties of the zeros of sampled-data systems. Since the basic study by Åström et al. that showed there can exist unstable zeros that have no relevance to the original continuous-time plant, there have been various studies that circumvent this effect by introducing various techniques. The present paper studies zeros of sampled-data systems from the standpoint of lifting. W

Relay autotuning has proven very successful for single-input single-output systems. This paper proposes an identification method for relay autotuning of systems with two inputs and two outputs (TITO systems). The combination of asymmetric relay feedback and output error identification admits short tuning time, without the need for limit cycle convergence. The method is successfully demonstrated on

Control and scheduling co-design becomes an issue when several controller tasks share the same execution platform and disrupt the ideal sampling and actuation patterns. In co-design the objective is to optimize the combined performance of all the controllers on the platform, subject to schedulability constraints. In the paper four LQG-based co-design methods are reviewed and evaluated: delay-aware

The paper presents conditions for the stability of a dynamical network described by a directed graph, whose nodes represent dynamical systems characterised by the same transfer function F(s) and whose edges account for the interactions between pairs of nodes. In turn, these interactions depend via a transference G(s) on the outputs of the subsystems associated with the connected nodes. The stabili

This paper presents new simple tuning rules for the gain in feedforward compensators. When the ideal feedforward controller is not possible to implement, a negative effect is introduced in the closed-loop response. So, the closed-loop transfer function from the disturbance to the error is analyzed and tuning rules for the feedforward gain are proposed. Two feedforward structures are used, a lead-l