'Hear Israel:' The involvement of Jews in education of the deaf

During the last two centuries there has been a methodological struggle over teaching the deaf. Do deaf people learn to communicate by means of gestures and signs (the "manual method") or is it important for them to learn speech and lip-reading (the "oral method")? In the second half of the nineteenth century, many schools for the deaf made the transition from the manual to the oral method, which the Milan conference of teachers of the deaf decided to promote in 1880. In this conversion, Jews played an important role. Yet there appears to be a clear link between their efforts and Jewish tradition, including its perception of the deaf. © 2008 The Author(s)

Kwaliteitsimpuls groenblauwe dooradering voor natuurlijke plaagonderdrukking in de Hoeksche Waard

Dit schetsboek geeft inzicht in de voorwaarden voor natuurlijke plaagonderdrukking in de akkerbouw. Het uiteindelijke doel is een bijdrage te leveren aan de ontwikkeling van een duurzame landbouw die minder afhankelijk is van chemische bestrijdingsmiddelen. Het focust op de kwalitatieve randvoorwaarden waar de groenblauwe dooradering aan moet voldoen om natuurlijke plaagonderdrukking mogelijk te maken. Daarbij gaat het om soorten, structuur en beheer van vegetaties in de groenblauwe dooradering. In de Hoeksche Waard is geanalyseerd in hoeverre de huidige situatie voldoet aan de randvoorwaarden. Samen met diverse actoren uit het gebied is gekeken welke strategieën te volgen zijn en welke stappen nodig zijn om een kwaliteitsimpuls in het gebied te realiseren. Het blijkt dat zowel op individueel bedrijfsniveau als op het niveau van het hele gebied maatregelen nodig zijn die bijdragen aan een duurzame landbouw

Dynamic wind farm flow control using free-vortex wake models

A novel dynamic economic model-predictive control strategy is presented that improves wind farm power production and reduces the additional demands of wake steering on yaw actuation when compared to an industry state-of-the-art reference controller. The novel controller takes a distributed approach to yaw control optimisation using a free-vortex wake model. An actuator-disc representation of the wind turbine is employed and adapted to the wind-farm scale by modelling secondary effects of wake steering and connecting individual turbines through a directed graph network. The economic model-predictive control problem is solved on a receding horizon using gradient-based optimisation, demonstrating sufficient performance for realising real-time control. The novel controller is tested in a large-eddy simulation environment and compared against a state-of-the-art look-up table approach based on steady-state model optimisation. Under realistic variations in wind direction and wind speed, the novel controller yields additional gains in power production during transients as well as a reduction in yaw actuator usage

The potential of wave feedforward control for floating wind turbines: a wave tank experiment

Floating wind energy has attracted substantial interest since it enables the deployment of renewable wind energy in deeper waters. Compared to the bottom-fixed turbines, floating wind turbines are subjected to more disturbances, predominantly from waves acting on the platform. Wave disturbances cause undesired oscillations in rotor speed and increase structural loading. This paper focuses on investigating the potential of using wave preview measurement in the control system labeled as wave feedforward to mitigate the effects of the wave disturbances. Two wave feedforward controllers were designed: one to reduce generator power oscillations and the other one to minimize the platform pitch motion. In this study, a software-in-the-loop wave tank experiment is presented for the purpose of investigating the potential of these wave feedforward controllers. In the experiment, a 1:40 scaled model of the DTU 10 MW reference wind turbine is used on top of a spar platform, with the baseline feedback control functionalities. Different environmental conditions, including wind speed, significant wave height, turbulence intensity, and wave spreading, were applied during the experiments to test the feedforward control performance and their effect on the turbine dynamics in general. It was found that the feedforward controller for the generator power reduces the power fluctuations properly with a fair control effort, while the one for platform pitch motion requires almost double the actuation duty for the same percentage reduction. Furthermore, the feedforward controller was able to counteract the wave disturbance at different wave heights and directions. However, it could not do much with increasing turbulence intensity as wind turbulence was found to have more dominance on the global dynamic response than waves.</p

Expert Elicitation on Wind Farm Control

Wind farm control is an active and growing field of research in which the control actions of individual turbines in a farm are coordinated, accounting for inter-turbine aerodynamic interaction, to improve the overall performance of the wind farm and to reduce costs. The primary objectives of wind farm control include increasing power production, reducing turbine loads, and providing electricity grid support services. Additional objectives include improving reliability or reducing external impacts to the environment and communities. In 2019, a European research project (FarmConners) was started with the main goal of providing an overview of the state-of-the-art in wind farm control, identifying consensus of research findings, data sets, and best practices, providing a summary of the main research challenges, and establishing a roadmap on how to address these challenges. Complementary to the FarmConners project, an IEA Wind Topical Expert Meeting (TEM) and two rounds of surveys among experts were performed. From these events we can clearly identify an interest in more public validation campaigns. Additionally, a deeper understanding of the mechanical loads and the uncertainties concerning the effectiveness of wind farm control are considered two major research gaps

Long-term research challenges in wind energy – a research agenda by the European Academy of Wind Energy

The European Academy of Wind Energy (eawe), representing universities and institutes with a significant wind energy programme in 14 countries, has discussed the long-term research challenges in wind energy. In contrast to research agendas addressing short- to medium-term research activities, this eawe document takes a longer-term perspective, addressing the scientific knowledge base that is required to develop wind energy beyond the applications of today and tomorrow. In other words, this long-term research agenda is driven by problems and curiosity, addressing basic research and fundamental knowledge in 11 research areas, ranging from physics and design to environmental and societal aspects. Because of the very nature of this initiative, this document does not intend to be permanent or complete. It shows the vision of the experts of the eawe, but other views may be possible. We sincerely hope that it will spur an even more intensive discussion worldwide within the wind energy community

Course and prognosis of recovery for chronic non-specific low back pain: design, therapy program and baseline data of a prospective cohort study

Background: There has been increasing focus on factors predicting the development of chronic musculoskeletal disorders. For patients already experiencing chronic non-specific low back pain it is also relevant to investigate which prognostic factors predict recovery. We present the design of a cohort study that aims to determine the course and prognostic factors for recovery in patients with chronic non-specific low back pain. Methods/Design. All participating patients were recruited (Jan 2003-Dec 2008) from the same rehabilitation centre and were evaluated by means of (postal) questionnaires and physical examinations at baseline, during the 2-month therapy program, and at 5 and 12 months after start of therapy. The therapy protocol at the rehabilitation centre used a bio-psychosocial approach to stimulate patients to adopt adequate (movement) behaviour aimed at physical and functional recovery. The program is part of regular care and consists of 16 sessions of 3 hours each, over an 8-week period (in total 48 hours), followed by a 3-month self-management program. The primary outcomes are low back pain intensity, disability, quality of life, patient's global perceived effect of recovery, and participation in work. Baseline characteristics include information on socio-demographics, low back pain, employment status, and additional clinical items status such as fatigue, duration of activities, and fear of kinesiophobia. Prognostic variables are determined for recovery at short-term (5 months) and long-term (12 months) follow-up after start of therapy. Discussion. In a routine clinical setting it is important to provide patients suffering from chronic non-specific low back pain with adequate information about the prognosis of their complaint

Passive movement therapy in patients with moderate to severe paratonia; study protocol of a randomised clinical trial (ISRCTN43069940)

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