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Flywheel Energy Storage Systems (FESSs) are a rather competitive short-term energy storage candidate due to its long lifetime, high power density, high cycle efficiency, and more significantly, high reliability and fast dynamic response. They are very suitable for applications with numerous charge and discharge cycles (up to hundreds of thousands) and medium to high power (kW to MW) during short periods (seconds to minutes), which contributes to their wide application prospects in the fields of uninterruptible power supplies, micro-grid regulations, wind power plants, rail transits, hybrid vehicles etc. High-speed Permanent Magnet Synchronous Motors/Generators (PMSMs/Gs) are one of the most commonly used electric machines in an FESS thanks to their high power density, low operating loss and flexible bidirectional power flow. However, when operating periodically in fast charge/discharge cycles, the performance of the universally used proportional-integral (PI) control theory based methods cannot fully meet the requirements of an FESS at a high electrical frequency within a wide speed range. Therefore, this study is focused on the control strategy improvement of high-speed PMSM/G in an FESS by taking the PMSM/G and its converter system as a combined control object. The detailed contents include:The dynamic model of the combined system of PMSM/G and converter is established, and the specific operation requirements of the FESS are discussed. The major drawbacks of the current control techniques of high-speed PMSMs/Gs and three-phase PWM converters are concluded and the possible research focus is pointed out. The working principle of the high-speed PMSM/G is analyzed in charging and discharging mode, respectively. The available operation range of the FESS within voltage, current and load boundary conditions is derived through voltage and current limit circle and equipower curve analysis methods, based on which a FESS prototype with rated power of 2.5 kW and rated speed of 12000rpm is built.A robust DC-link voltage control strategy with load power and speed compensation is proposed for wide speed range operation of an FESS. Wide speed range operation in discharging mode is essential for ensuring discharge depth and energy storage capacity of a FESS. However, for a PMSM/G-based FESS, the wide-range speed variation in a short discharging period causes consecutive decreases in ac voltage frequency and amplitude. As a result, the operating point shift leads to performance deterioration of the conventional local linearization based DC-link voltage control strategies. Therefore, a robust control strategy that incorporates the speed variation to the DC-link voltage controller is proposed to realize a consistent performance within the entire available operation range of the FESS. The nonlinear DC-link voltage loop model is globally linearized by treating the square of DC-link voltage as the state variable, and lumping the nonlinear and uncertain terms proportional to the load power and parameter errors in the power balance equation as the total disturbance. A speed adaptive feedback control law is designed to ensure consistent dynamic performance within the entire available operation range.A fast single loop DC-link voltage direct control strategy for high-speed PMSM/G of an FESS is proposed to improve its dynamic performance. Instead of the conventional strategy with cascaded outer DC-link voltage loop and inner current loop, the proposed strategy is a single loop direct voltage control strategy without an intermediate current loop. The DC-link voltage loop and q-axis current loop are integrated together to a 3rd-order extended system. A linear extended state observer (ESO) is designed to observe the 3rd-order extended system and derive the differential of the square of DC-link voltage; a control law that incorporates proportional and differential feedback, as well as speed variation and total disturbance compensation is proposed. The inner dynamics of the linear ESO are analyzed through bode diagrams, and the tracking performance and anti-disturbance capability of the proposed strategy is hereby derived.The delay compensation and cross-coupling problem of a discrete current controller for high-speed PMSM/G is studied. The high-speed PMSM/G in a FESS is faced with higher cross-coupling voltages and lower switching-to-fundamental frequency ratios. High cross-coupling voltage leads to transient error in the current tracking. If the current controller design does not properly incorporate the delays in a digital control system, the lower switching-to-fundamental-frequency ratio may result in oscillatory or unstable behaviors. Instead of discretizing a continuous controller with approximate methods such as the Euler difference and the Tustin transformation, an accurate discrete current controller is proposed based on an accurate discrete model. The model takes the phase and magnitude errors produced during the sampling period into consideration, and an Extended State Observer (ESO) applied to estimate and compensate the back EMF error. The cross-coupling problem between d-q axis current loops is well solved, and the dynamic performance of the current loop at lower switching-to-fundamental frequency ratios is improved. The dynamic performance and robustness of the three controllers proposed and designed in this thesis are validated by simulations and experiments on the 12000 rpm FESS prototype. Results at different speeds prove the efficiency and improvement at wide speed range operation and low switching-to-fundamental-frequency ratios. Doctorat en Sciences de l'ingénieur et technologie info:eu-repo/semantics/nonPublished

An Electric Boat works similar to an electric car. It has an electric motor , a controller and a battery pack for power to run it . It also has a charging controller so the batteries can be recharged . The motor size depends on the boat size as does the battery pack. The operating principle of electric boats that are driven by electric energy stored in the batteries and also it’s propellor operated by using the DC motor or INDUCTION motor. we have implementation of our project is renewable energy run in e-boat Motor and battery management system. By using various sensors we have to measure the voltage in the battery system and show the measurements in the LCD display and calculations are implemented in the back end embedded C programming.

Community based tourism (CBT) focuses on the protection of socio-cultural values and economic benefits of stakeholder host communities of tourism destinations. It is increasingly being promoted as an avenue of sustainable tourism development. But for achieving economic sustainability in long run for CBT initiatives it is imperative to ensure revenue generation through regular tourist footfall and productive use of available resources. The purpose of the study is to examine the tourists’ awareness level about CBT initiatives. The paper also seeks to analyze how far the aware tourist is able to contribute to economic sustainability of CBT destinations. It also aims to identify popular tourist information dissemination sources so that a policy prescription can be suggested for effective marketing and promotion strategy of CBT. The study used questionnaire based survey method and collected primary data of 100 domestic tourists focusing on the CBT destinations of Northern part of west Bengal region. Statistical analysis is used to develop a framework to explain the theoretical relationship of CBT awareness level and tourists’ visit possibility. The findings will lead to policy prescriptions for CBT developers to achieve sustainability in long run by developing unique promotional strategy to increase tourist visit.

The impact of empty-bed contact time and temperature on the efficiency of biological GAC filtration has been studied on pilot filters at the Neuilly-sur-Marne treatment plant. Fixed bacterial biomass was investigated using a method of potential respiration of labelled glucose and the filtration efficiency was characterized by the removal of biodegradable dissolved organic carbon (BDOC). With a fixed bacterial carbon biomass of c. 2 mg/l, pilots with empty-bed contact times of 10 min removed around 60% of BDOC. The net exportation of bacterial biomass was very low when compared to the removal of BDOC achieved by the filtration. BDOC removal increased with increasing empty-bed contact times in the tested range of filtration velocities (6-18 m/h). Data showed that it was necessary to double the empty-bed contact time when temperature decreased from 20 degree C to 8 degree C to keep a similar BDOC removal efficiency, although the average bacterial biomass was the same at both temperatures. info:eu-repo/semantics/published

This article presents a set of measures for evaluating a social development programme such as the non-conventional energy programme. The specific case discussed and evaluated here is that of the solar cooker programme. Subsequently, the attempt is to identify key decision areas and raise some questions which may help focus better on the marketing problems confronting the programme.

Sustainable agriculture leads today to important questions about the diversification of agricultural production and sources of income for farmers, the use of rural and arable land for food and non-food crops, the contribution of agriculture to climate change fighting and the supply of renewable energy. Bioenergy from agriculture is at the heart of these concerns, integrating sustainable development key components: environment and climate change, energy economics and energy supply, agriculture, rural and social development. The lack of primary and reliable data on bioenergy externalities from agriculture and the lack of decision-making tools are important non-technological barriers to the development of bioenergy from agriculture on a large scale, and, consequently, to the achievement of the national and regional objectives of sustainable development with respect to greenhouse gas mitigation, secure and diversified energy supply, rural development and employment and the future of agriculture. Furthermore, the recent worldwide controversies about transport biofuels, food shortages and increasing prices have demonstrated the urgent need for sustainability criteria applied to biofuels and bioenergy. Within this current sustainable development framework, a project entitled TEXBIAG integrating experts from 4 research institutions is financed by the Belgian Science Policy. The final objective of this project is to lead to an actual and significant contribution of bioenergy from agriculture to the mitigation of greenhouse gas emissions, to a secure and diversified energy supply and to farmers' incomes and rural development. To reach this final objective, the project develops three specific tools: (1) a database of primary quantitative data related to environmental and socio-economic impacts of bioenergy from agriculture integrating biomass logistics; (2) a mathematical model monetizing bioenergy externalities from agriculture; and (3) a prediction tool assessing the impacts of political decisions made in the framework ofthe development of bioenergy from agriculture on different economic sectors (energy, agriculture, industry, and environment). An integrated interface tool will be programmed where access to and update of the three tools will be prepared. The project methodology will be conducted for a given number of scenarios with sensitivity analysis wherever possible. The three main target groups that will benefit from the project are: the government officials and policy makers in the field of agriculture, energy and environment in Belgium and its two main regions, the small, medium and large energy companies and the agricultural sector

> Les pays riches doivent faire beaucoup plus, beaucoup plus vite. L'Assemblée générale des Nations Unies en septembre 2021 réunira les pays à un moment critique pour organiser une action collective pour faire face à la crise environnementale mondiale. Ils se réuniront à nouveau lors du sommet sur la biodiversité à Kunming, en Chine, et de la conférence sur le climat (Conférence des Parties (COP)26) à Glasgow, au Royaume-Uni. Avant ces réunions cruciales, nous - les rédacteurs en chef des revues de santé du monde entier - appelons à une action urgente pour maintenir les augmentations moyennes de la température mondiale en dessous de 1,5 ° C, arrêter la destruction de la nature et protéger la santé. La santé est déjà affectée par l'augmentation de la température mondiale et la destruction du monde naturel, un état de fait sur lequel les professionnels de la santé attirent l'attention depuis des décennies.1 La science est sans équivoque ; une augmentation mondiale de 1,5 ° C au-dessus de la moyenne préindustrielle et la perte continue de la biodiversité risquent de causer des dommages catastrophiques à la santé qu'il sera impossible d'inverser.2 3 Malgré la préoccupation nécessaire du monde concernant la COVID-19, nous ne pouvons pas attendre que la pandémie passe pour réduire rapidement les émissions. Reflétant la gravité du moment, cet éditorial apparaît dans des revues de santé à travers le monde. Nous sommes unis pour reconnaître que seuls des changements fondamentaux et équitables dans les sociétés inverseront notre trajectoire actuelle. Les risques pour la santé des augmentations supérieures à 1,5 °C sont maintenant bien établis.2 En effet, aucune augmentation de température n'est « sûre ». Au cours des 20 dernières années, la mortalité liée à la chaleur chez les personnes âgées de plus de 65 ans a augmenté de plus de 50 %.4 Des températures plus élevées ont entraîné une augmentation de la déshydratation et de la perte de la fonction rénale, des tumeurs malignes dermatologiques, des infections tropicales, des problèmes de santé mentale, des complications de grossesse, des allergies et une morbidité et une mortalité cardiovasculaires et pulmonaires.5 6 Les préjudices affectent de manière disproportionnée les plus vulnérables, notamment les enfants, les populations plus âgées, les minorités ethniques, les communautés les plus pauvres et les personnes ayant des problèmes de santé sous-jacents.2 4 Le réchauffement climatique contribue également à la baisse de ... > Las naciones ricas deben hacer mucho más, mucho más rápido. La Asamblea General de las Naciones Unidas en septiembre de 2021 reunirá a los países en un momento crítico para organizar la acción colectiva para abordar la crisis ambiental mundial. Se reunirán nuevamente en la cumbre de biodiversidad en Kunming, China, y en la conferencia climática (Conferencia de las Partes (COP)26) en Glasgow, Reino Unido. Antes de estas reuniones fundamentales, nosotros, los editores de revistas de salud de todo el mundo, pedimos medidas urgentes para mantener el aumento promedio de la temperatura global por debajo de 1,5 ° C, detener la destrucción de la naturaleza y proteger la salud. La salud ya se está viendo perjudicada por el aumento de la temperatura global y la destrucción del mundo natural, una situación a la que los profesionales de la salud han estado prestando atención durante décadas.1 La ciencia es inequívoca; un aumento global de 1,5 ° C por encima del promedio preindustrial y la continua pérdida de biodiversidad corren el riesgo de causar daños catastróficos a la salud que serán imposibles de revertir.2 3 A pesar de la preocupación necesaria del mundo por el COVID-19, no podemos esperar a que la pandemia pase para reducir rápidamente las emisiones. Como reflejo de la gravedad del momento, este editorial aparece en revistas de salud de todo el mundo. Estamos unidos en el reconocimiento de que solo los cambios fundamentales y equitativos en las sociedades revertirán nuestra trayectoria actual. Los riesgos para la salud de aumentos superiores a 1,5 °C están ahora bien establecidos.2 De hecho, ningún aumento de temperatura es "seguro". En los últimos 20 años, la mortalidad relacionada con el calor entre las personas mayores de 65 años ha aumentado en más del 50%.4 Las temperaturas más altas han provocado un aumento de la deshidratación y la pérdida de la función renal, neoplasias malignas dermatológicas, infecciones tropicales, resultados adversos para la salud mental, complicaciones del embarazo, alergias y morbilidad y mortalidad cardiovascular y pulmonar.5 6 Los daños afectan de manera desproporcionada a los más vulnerables, incluidos los niños, las poblaciones mayores, las minorías étnicas, las comunidades más pobres y las personas con problemas de salud subyacentes.2 4 El calentamiento global también está contribuyendo a la disminución de ... > Wealthy nations must do much more, much faster. The United Nations General Assembly in September 2021 will bring countries together at a critical time for marshalling collective action to tackle the global environmental crisis. They will meet again at the biodiversity summit in Kunming, China, and the climate conference (Conference of the Parties (COP)26) in Glasgow, UK. Ahead of these pivotal meetings, we—the editors of health journals worldwide—call for urgent action to keep average global temperature increases below 1.5°C, halt the destruction of nature and protect health. Health is already being harmed by global temperature increases and the destruction of the natural world, a state of affairs health professionals have been bringing attention to for decades.1 The science is unequivocal; a global increase of 1.5°C above the preindustrial average and the continued loss of biodiversity risk catastrophic harm to health that will be impossible to reverse.2 3 Despite the world's necessary preoccupation with COVID-19, we cannot wait for the pandemic to pass to rapidly reduce emissions. Reflecting the severity of the moment, this editorial appears in health journals across the world. We are united in recognising that only fundamental and equitable changes to societies will reverse our current trajectory. The risks to health of increases above 1.5°C are now well established.2 Indeed, no temperature rise is 'safe'. In the past 20 years, heat-related mortality among people aged over 65 has increased by more than 50%.4 Higher temperatures have brought increased dehydration and renal function loss, dermatological malignancies, tropical infections, adverse mental health outcomes, pregnancy complications, allergies, and cardiovascular and pulmonary morbidity and mortality.5 6 Harms disproportionately affect the most vulnerable, including children, older populations, ethnic minorities, poorer communities and those with underlying health problems.2 4 Global heating is also contributing to the decline in … > يجب على الدول الغنية أن تفعل أكثر من ذلك بكثير، وأسرع بكثير. ستجمع الجمعية العامة للأمم المتحدة في سبتمبر 2021 البلدان في وقت حرج لحشد العمل الجماعي لمعالجة الأزمة البيئية العالمية. وسيجتمعون مرة أخرى في قمة التنوع البيولوجي في كونمينغ، الصين، ومؤتمر المناخ (مؤتمر الأطراف 26) في غلاسكو، المملكة المتحدة. قبل هذه الاجتماعات المحورية، ندعو - نحن محرري المجلات الصحية في جميع أنحاء العالم - إلى اتخاذ إجراءات عاجلة للحفاظ على متوسط الزيادات في درجات الحرارة العالمية أقل من 1.5 درجة مئوية، ووقف تدمير الطبيعة وحماية الصحة. الصحة تتضرر بالفعل من ارتفاع درجات الحرارة العالمية وتدمير العالم الطبيعي، وهو وضع يلفت الانتباه إليه المهنيون الصحيون منذ عقود. 1 العلم لا لبس فيه ؛ زيادة عالمية قدرها 1.5 درجة مئوية فوق متوسط ما قبل الصناعة واستمرار فقدان التنوع البيولوجي خطر ضرر كارثي على الصحة سيكون من المستحيل عكسه. 2 3 على الرغم من الانشغال العالمي الضروري بـ COVID -19، لا يمكننا الانتظار حتى ينتقل الوباء لتقليل الانبعاثات بسرعة. مما يعكس شدة اللحظة، تظهر هذه الافتتاحية في المجلات الصحية في جميع أنحاء العالم. نحن متحدون في الاعتراف بأن التغييرات الأساسية والعادلة في المجتمعات هي وحدها التي ستعكس مسارنا الحالي. أصبحت المخاطر الصحية للزيادات التي تزيد عن 1.5 درجة مئوية ثابتة الآن. 2 في الواقع، لا يوجد ارتفاع في درجة الحرارة "آمن". في السنوات العشرين الماضية، زادت الوفيات المرتبطة بالحرارة بين الأشخاص الذين تزيد أعمارهم عن 65 عامًا بأكثر من 50 ٪.4 وقد أدت درجات الحرارة المرتفعة إلى زيادة الجفاف وفقدان وظائف الكلى، والأورام الخبيثة الجلدية، والالتهابات الاستوائية، والنتائج السلبية للصحة العقلية، ومضاعفات الحمل، والحساسية، واعتلال القلب والأوعية الدموية والرئوية والوفيات .5 6 تؤثر الأضرار بشكل غير متناسب على الفئات الأكثر ضعفًا، بما في ذلك الأطفال وكبار السن والأقليات العرقية والمجتمعات الفقيرة وأولئك الذين يعانون من مشاكل صحية كامنة .2 4 يساهم التدفئة العالمية أيضًا في انخفاض...