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Book Description
Sous l'effet d'une insolation lumineuse (en général ultraviolette), l'indice de réfraction de la plupart des verres de silice se modifie de façon permanente. Cet effet est désigné sous le nom de photosensibilité. Le phénomène se révèle intéressant pour les télécommunications optiques dans la mesure où il permet l'inscription de composants optiques passifs dans le coeur des fibres optiques ou dans des films planaires. Dans le cadre de ce travail de doctorat, nous avons réalisé un ensemble d'études sur la photosensibilité de verres germanosilicates sous l'action d'insolations réalisées à l'aide d'un laser à ArF ([lambda]p=193nm)ou d'un laser à KrF ([lambda]p=248nm). Nous avons étudié trois différentes méthodes de sensibilisation des verres germanosilicates : l'hydrogénation à haute pression et à température ambiante, l'hypersensibilisation UV (hydrogénation, insolation unifor:me et dégazage) ainsi que la méthode de chargement en hydroxyles (élévation thermique à 1000ʿC durant un court instant puis dégazage). D'une part, il s'agissait de comparer les trois méthodes de sensibilisation des fibres optiques germanosilicates en terme d'efficacité, de 'stabilité des procédés et des variations d'indice ainsi que des pertes créées vers 1,5 micron. D'autre part, une étude destinée à préciser les mécanismes de la sensibilisation et les origines des changements d'indice a été présentée dans ce mémoire. A cet effet, nous avons enregistré les spectres d'excès de pertes induits dans l'infrarouge et l'ultraviolet lors de l'insolation UV de lames de préforme ou de fibres germanosilicates sensibilisées.
Book Description
Sous l'effet d'une insolation lumineuse (en général ultraviolette), l'indice de réfraction de la plupart des verres de silice se modifie de façon permanente. Cet effet est désigné sous le nom de photosensibilité. Le phénomène se révèle intéressant pour les télécommunications optiques dans la mesure où il permet l'inscription de composants optiques passifs dans le coeur des fibres optiques ou dans des films planaires. Dans le cadre de ce travail de doctorat, nous avons réalisé un ensemble d'études sur la photosensibilité de verres germanosilicates sous l'action d'insolations réalisées à l'aide d'un laser à ArF ([lambda]p=193nm)ou d'un laser à KrF ([lambda]p=248nm). Nous avons étudié trois différentes méthodes de sensibilisation des verres germanosilicates : l'hydrogénation à haute pression et à température ambiante, l'hypersensibilisation UV (hydrogénation, insolation unifor:me et dégazage) ainsi que la méthode de chargement en hydroxyles (élévation thermique à 1000ʿC durant un court instant puis dégazage). D'une part, il s'agissait de comparer les trois méthodes de sensibilisation des fibres optiques germanosilicates en terme d'efficacité, de 'stabilité des procédés et des variations d'indice ainsi que des pertes créées vers 1,5 micron. D'autre part, une étude destinée à préciser les mécanismes de la sensibilisation et les origines des changements d'indice a été présentée dans ce mémoire. A cet effet, nous avons enregistré les spectres d'excès de pertes induits dans l'infrarouge et l'ultraviolet lors de l'insolation UV de lames de préforme ou de fibres germanosilicates sensibilisées.
Book Description
Earthen architecture constitutes one of the most diverse forms of cultural heritage and one of the most challenging to preserve. It dates from all periods and is found on all continents but is particularly prevalent in Africa, where it has been a building tradition for centuries. Sites range from ancestral cities in Mali to the palaces of Abomey in Benin, from monuments and mosques in Iran and Buddhist temples on the Silk Road to Spanish missions in California. This volume's sixty-four papers address such themes as earthen architecture in Mali, the conservation of living sites, local knowledge systems and intangible aspects, seismic and other natural forces, the conservation and management of archaeological sites, research advances, and training.
Author: Publisher: Allied Publishers ISBN: 9780821344620 Category : Juvenile Nonfiction Languages : en Pages : 168
Book Description
South Asia Rural Development Series. India's economic policies are aimed at increasing economic growth, improving market efficiency and competitiveness, and integrating the Indian economy with global markets. Much of the population and industrial growth is expected to occur in urban centers. Consequently, the demands on the Urban Water Supply and Sanitation sector (UWSS), will be great. Urban Water Supply and Sanitation states the UWSS sector needs urgent attention both to meet these new demands and to ensure that all city-dwellers have access to basic services at reasonable costs. This book outlines the way forward which includes a discussion on institutional reform and financial reform as well an action plan.
Author: Food and Agriculture Organization of the United Nations Publisher: Food & Agriculture Org. ISBN: 9251305536 Category : Business & Economics Languages : en Pages : 435
Book Description
According to the report, the conference focused on the main challenges for the sustainable development of small-scale fisheries, including promoting political commitment and tailored strategies, raising awareness, and sharing knowledge.
Author: Bihini won wa Musiti Publisher: IUCN ISBN: 2831706904 Category : Conservation of natural resources Languages : ru Pages : 344
Book Description
This bilingual publication results from a four-day symposium aimed at capturing the general directions and analytical issues that characterize approaches to sustainable use in Africa. The papers included in this work are organized under four major headings: modes of use, devolution, scale issues and external issues. Authors explore these themes through the use of case studies and the description of specific regional experiences. External issues are further explored in a series of commissioned policy papers which have also been included.
Author: Martin Lindstrom Publisher: Currency ISBN: 0385523890 Category : Business & Economics Languages : en Pages : 274
Book Description
NEW YORK TIMES BESTSELLER • “A fascinating look at how consumers perceive logos, ads, commercials, brands, and products.”—Time How much do we know about why we buy? What truly influences our decisions in today’s message-cluttered world? In Buyology, Martin Lindstrom presents the astonishing findings from his groundbreaking three-year, seven-million-dollar neuromarketing study—a cutting-edge experiment that peered inside the brains of 2,000 volunteers from all around the world as they encountered various ads, logos, commercials, brands, and products. His startling results shatter much of what we have long believed about what captures our interest—and drives us to buy. Among the questions he explores: • Does sex actually sell? • Does subliminal advertising still surround us? • Can “cool” brands trigger our mating instincts? • Can our other senses—smell, touch, and sound—be aroused when we see a product? Buyology is a fascinating and shocking journey into the mind of today's consumer that will captivate anyone who's been seduced—or turned off—by marketers' relentless attempts to win our loyalty, our money, and our minds.
Author: Linda Strande Publisher: IWA Publishing ISBN: 1780404735 Category : Technology & Engineering Languages : en Pages : 428
Book Description
It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.
Author: Danielle R. Bouchard Publisher: Human Kinetics ISBN: 1492592161 Category : Medical Languages : en Pages : 354
Book Description
Go beyond aging theories and examine the physiological and physical impacts of aging. Exercise and Physical Activity for Older Adults takes a close look at the physical implications of the aging process and how health, physical activity, and exercise interact in aging adults. With an international team of contributors composed of leading experts from across the field of gerontology, Exercise and Physical Activity for Older Adults delivers comprehensive, interdisciplinary coverage of the physical aging process and its effects on movement and exercise. Research on the physiological and physical implications of aging is presented, focusing on study outcomes and their practical application in optimizing healthy aging. Presented in an integrated and cohesive manner, this text is organized into four parts. Part I covers the theoretical foundations of biological aging, the implications of aging theories on medical research, and the social and economic impacts of demographic shifts due to population aging and global population size. Part II addresses age-related changes to the musculoskeletal, cardiovascular, pulmonary, and endocrine systems. Part III covers the physical effects of aging on other dimensions of life, including balance, motor control, and physical functions. Part IV focuses on exercise and older adults, taking an in-depth look at exercise measurements and the main barriers to regular exercise. One full chapter is devoted to recommendations for optimizing health for the general public, while another chapter is focused on performance by elite older athletes who exercise beyond functional fitness. Chapter objectives, end-of-chapter summaries, and review questions highlight key concepts and promote learning retention. Behavior Check sidebars look at the impacts of aging on behavior, how behavior affects physical health and activity, and how changes in behavior can improve everyday living. Functional Fitness Checkup sidebars focus on the performance of daily movements that are vital for older adults who want to maintain their physical independence. Putting It Into Practice elements provide examples of real-life application of the concepts presented, facilitating a practical understanding of how to use the content to benefit clients. A definitive resource for students and health care professionals who study physical aging, conduct clinical research, or work with older adults as clients and patients, Exercise and Physical Activity for Older Adults helps readers understand the aging process and its effects on movement, exercise, and other dimensions of life.
Author: Matthieu Lancry
Author: Matthieu Lancry
Author: Leslie Rainer
Author: 
Author: Food and Agriculture Organization of the United Nations
Author: Bihini won wa Musiti
Author: Martin Lindstrom
Author: Linda Strande
Author: Stuart Hill
Author: Danielle R. Bouchard
Author: Canada. Industry Canada