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Book
Ultra-Broadly Tunable Light Sources Based on the Nonlinear Effects in Photonic Crystal Fibers
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ISBN: 3662483599 3662483602 Year: 2016 Publisher: Berlin, Heidelberg : Springer Berlin Heidelberg : Imprint: Springer,

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This thesis examines laser generation from the ultraviolet to the short edge of the mid-infrared band by exploiting the nonlinear effects in photonic crystal fibers (PCFs). Several different physical mechanisms are investigated by using homemade PCFs with elaborately customized dispersion profiles. A particular focus is on the development of fiber optical parametric amplifiers (FOPAs) and oscillators (FOPOs) based on the PCFs with a zero-dispersion wavelength of ca. 1.06 μm. In particular, several schemes are proposed for solving the key problems involved in the application of FOPOs. These oscillators can be made more convenient to use by optimizing the wavelength-tuning mechanisms, and made more energy-efficient with the help of specially designed cavity structures. Today’s oscillators are more reliable, powerful and maneuverable than ever. This thesis provides a systematic road map in connection with the study of nonlinear wavelength generation in PCFs, from their fiber design and technical fabrication, to their physical mechanism and experimental investigation.


Digital
Ultra-Broadly Tunable Light Sources Based on the Nonlinear Effects in Photonic Crystal Fibers
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ISBN: 9783662483602 Year: 2016 Publisher: Berlin, Heidelberg Springer

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Abstract

This thesis examines laser generation from the ultraviolet to the short edge of the mid-infrared band by exploiting the nonlinear effects in photonic crystal fibers (PCFs). Several different physical mechanisms are investigated by using homemade PCFs with elaborately customized dispersion profiles. A particular focus is on the development of fiber optical parametric amplifiers (FOPAs) and oscillators (FOPOs) based on the PCFs with a zero-dispersion wavelength of ca. 1.06 μm. In particular, several schemes are proposed for solving the key problems involved in the application of FOPOs. These oscillators can be made more convenient to use by optimizing the wavelength-tuning mechanisms, and made more energy-efficient with the help of specially designed cavity structures. Today’s oscillators are more reliable, powerful and maneuverable than ever. This thesis provides a systematic road map in connection with the study of nonlinear wavelength generation in PCFs, from their fiber design and technical fabrication, to their physical mechanism and experimental investigation.


Article
Economic development and land-use conversion in the main course area of the Yangtse river basin
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Book
Sub-Kelvin scanning tunneling microscopy on magnetic molecules
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Year: 2019 Publisher: Karlsruhe : KIT Scientific Publishing,

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Magnetic molecules have attracted lots of interest. In this work, an ultra-stable and low noise scanning tunneling microscopy operating at 400 mK using He-3 (930 mK using He-4) has been developed. The magnetic behavior of different magnetic molecules on substrates, especially the exchange interaction between the magnetic ions, the magnetic anisotropy on the surface, the magnetic excitations as well as the Kondo effect, were studied by using STM.


Book
Affect, emotion and rhetorical persuasion in mass communication
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ISBN: 9780815374381 0815374380 9780815374398 0815374399 9781351242363 1351242369 9781351242370 9781351242356 1351242350 9781351242349 1351242342 1351242377 Year: 2019 Publisher: New York, N.Y.: Routledge,

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"This volume examines the interplay between affect theory and rhetorical persuasion in mass media communication. It is divided into three sections--affect theory, general case studies, and case studies on the 2016 U.S. Presidential Election--and offers perspectives from authors around the world. With chapter-by-chapter discussion questions, as well as links to further research online, this text offers both a theoretical overview and the latest research in the field. Interdisciplinary in approach, it will be of use to advanced undergraduate and graduate students in communication, rhetoric, political science, social psychology, sociology, and cultural studies"--


Book
A Chinese perspective on WTO reform
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ISBN: 9811982309 9811982295 Year: 2023 Publisher: Singapore : Springer,

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This book discusses the most recent developments in the WTO regime. Issues such as E-commerce, security exception clause, China's compliance with the WTO obligations, sustainability development, IP protection in FTZs, trade controls and etc., are at the forefront of WTO studies. These issues strongly influence people's understanding of the current role of WTO and provides possible way to revitalize the function of WTO. Meanwhile, as the world's second largest economy, the world's largest trading nation and the holder of the world's largest foreign exchange reserves, China is apparently a powerful figure in leading these issues. Therefore, this book explores extensively these issues from a Chinese perspective to see what China could do to reboost the world trade.


Book
Principles and practices of transportation planning and engineering : a foundational reference for professionals and textbook for students focusing on civil et transportation engineering, planning, environmental science, and project management
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ISBN: 1003145175 1003145175 1000366324 1000366367 Year: 2021 Publisher: Boca Raton, FL ; London ; New York : CRC Press, Taylor & Francis Group,

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Connie Kelly Tang and Lei Zhang have provided a holistic coverage of the entire surface transportation project and program development process from the beginning of planning though environmental approval, design, right-of way acquisition, construction to operations and maintenance.-- Neil Pedersen, Executive Director, Transportation Research Board, National Academies of Sciences, Engineering, and Medicine, Washington, DC Transportation program and project development is complex. The process spans over planning, programming, environment, design, right of way, construction, operations, and maintenance. Professionals from civil engineering, planning, social and environmental sciences, business and project management, and data science, work together in a relay team to transform an idea into a highway, a transit hub, an airport or a water facility. It is challenging for any one person to master all the knowledge and skills needed to perform every relevant task. However, it is critical for all involved to understand how this relay works and how the societal, environmental, governmental, and regulatory contexts influence the process and the technical solution. Professionals who understand the process and see the big picture are those who rise to the top as leaders. Transportation Project and Program Development provides holistic coverage on the technical subject matter, processes and procedures, and policy and guidance associated with transportation project and program development, which can help professionals become program leaders. For each phase of the process, key products delivered, processes used, governing principles, foundations of applicable science and engineering, technologies deployed, and knowledge required are discussed. While all coverages reflect the practices of the United States, the logic, principles, science, and engineering are applicable to all countries of the world. The book can also serve as an introductory textbook for undergraduate students and as a textbook or reference for a graduate-level course in civil engineering, transportation engineering, planning, and project management.


Book
Cloud data center network architectures and technologies
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ISBN: 1003143180 1003143180 1000375595 Year: 2021 Publisher: Boca Raton, Florida ; London ; New York : CRC Press,

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"This book has been written with the support of Huawei's large accumulation of technical knowledge and experience in the data center network (DCN) field, as well as its understanding of customer service requirements. This book describes in detail the architecture design, technical implementation, planning and design, and deployment suggestions for cloud DCNs based on the service challenges faced by cloud DCNs. This book starts by describing the overall architecture and technical evolution of DCNs, with the aim of helping readers understand the development of DCNs. It then proceeds to explain the design and implementation of cloud DCNs, including the service model of a single data center (DC), construction of physical and logical networks of DCs, construction of multiple DCNs, and security solutions of DCs. Next, this book dives deep into practices of cloud DCN deployment based on real-world cases to help readers better understand how to build cloud DCNs. Finally, this book introduces DCN openness and some of the hottest forward-looking technologies. In summary, you can use this book as a reference to help you to build secure, reliable, efficient, and open cloud DCNs. It is intended for technical professionals of enterprises, research institutes, information departments, and DCs, as well as teachers and students of computer network-related majors in colleges and universities"--

Keywords

Cloud computing.


Dissertation
Prediction of feed efficiency based on test-day liveweight of dairy cows estimated using animal characteristics and milk mid-infrared spectra
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Year: 2021

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Due to the increasing world population, the consumption of milk and dairy products is raising. Optimizing the production of milk under the economic and environmental constraints is a challenge. In this context, knowing the feed efficiency (FE) of dairy cow is a key issue. Unfortunately, the acquisition of such records at individual and large scales is unfeasible. So, the current thesis aims to fill this gap by developing a FE predictive tool for dairy sector available at large and individual scales. To achieve this objective, the FE was assessed by calculating the ratio of fat and protein corrected milk (FPCM) to dry matter intake (DMI). Although FPCM is already routinely available, this is not the case for DMI. However, a literature equation exists to predict DMI from FCM, live bodyweight (BW) and the number of weeks of lactation. Recently, a methodology using the milk mid-infrared (MIR) spectrometry combined with the animal characteristics was developed to predict test-day BW records, leading to open new perspectives about the use of FE related traits for management and breeding purposes. So, the final achievement of this thesis is the development and the implementation of a FE prediction tool from traits easily recorded by dairy herd improvement (DHI) organizations, including namely the BW estimation. To achieve this objective, 3 main research activities were conducted in this thesis.The first research aimed to increase the calibration set and to apply feature selection algorithms during the modeling in order to improve the BW models' robustness and accuracy. Indeed, the presence of less informative variables in a prediction equation could impact negatively its robustness. Three feature selection algorithms were applied on 280 predictors to select the most informative ones from a dataset containing 5,920 records: partial least squares regression (PLS) combined with sum of ranking difference (SRD), PLS combined with uninformative variables elimination (UVE), and the output of Elastic net regression (EN). Parity, days in milk (DIM), milk yield (MY), and two MIR spectral points were selected as the most relevant variables to predict BW. Validation root mean square errors (RMSEp) of 60 kg were obtained for both PLS and EN regressions employing these 5 predictors, suggesting a better robustness of these models compared to the ones without MIR or using all 277 MIR variables. The RMSE values of validation set coming from another brand of spectrometer were around 64 kg.The second research work focused on the implementation of a BW equation in practice. Indeed, some poor quality BW predictions can be obtained using poor quality spectral data or by applying the model on samples for which the variability was not included in the calibration set. So, the objective of this work was to develop data cleaning methods easy to implement by DHI to ensure the quality of BW predictions. So, 3 data cleaning procedures and their combinations were tested on a DHI dataset containing 346,818 records: the deletion of 1% of extreme high and low predicted values (M1), the deletion of records when the global-H (GH) distance was greater than 5 (M2), and the deletion of records if the absolute fat residual value was higher than 0.30 g/dL of milk (M3). The interest of those procedures was assessed by estimating the root mean square differences (RMSD) between fat, protein, and fatty acids traits predicted by the MIR spectrometry internally and externally. All methods allowed to decrease RMSD, the gain ranged from 0.32% to 41.39%. Based on the obtained results, the "M1 and M2" combination should be preferred to be more parsimonious in the data loss as it had the higher ratio of RMSD gain to data loss. However, to ensure the lowest RMSD, the "M2 or M3" combination was the most relevant.Based on these 2 first works, FE records were easily obtained at large and individual scales and cleaned appropriately. Then, in order to assess the relevancy of the FE tool, the final work of this thesis consisted to study the behaviors of BW and FE predictions obtained from the 5 developed equations within and between lactations as well as per test month and compared them to the ones observed in the literature using reference values. Subsets of Hebei (N=288,607) and Walloon (N=379,472) DHI datasets were used. Even if the BW equations did not differ a lot based on the prediction performances, differences were observed on the DHI datasets and clustered the equations within 2 groups: the ones including 5 predictors and the one using the parity, DIM, MY, and the full MIR spectral data. The final one depicted a more expected evolution within lactation with a drop of BW around 30-50 days in milk and then an increase. This was not observed for the other equations suggesting a lack of MIR information to take into account sufficiently the individual variability of BW. The annual trend observed for this equation was also more expected with a BW drop during the grazing period. However, the differences in FE predictions obtained using BW estimated from different equations were less marked, suggesting a low sensibility of FE predictions to a moderate variation of BW. The validation RMSE reached 0.05 suggesting a good accuracy for this FE indicator.In conclusion, the FE tool developed in this thesis can be implemented by DHI organizations based on the BW equation including milk, parity, DIM, and the 277 MIR spectral points. However, some additional investigations are still needed before the use of a such tool by DHI. Indeed, even if preliminary results obtained in this thesis suggested a moderate heritability of FE trait, a study with the newly developed BW equations could be done as we have observed that the past BW equation tended to overestimate BW. Moreover, knowing the relationships between FE predictions with other traits having economic interest is required before any use. A reflection about the best way to communicate the results to the farmers must be also started. Finally, the FE tool was based on an equation predicting DMI. For the future, it could be also of interest to measure the relevancy of this equation by using DMI reference data.

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Dissertation
Silicon micro-pillar array columns for liquid chromatography of DNA
Authors: ---
ISBN: 9789460187087 Year: 2013 Publisher: Leuven Katholieke Universiteit Leuven

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The miniaturization of clinical analyses of human biological samples in a simple handheld device has long been sought after for clinical medicine and patient care. Such a miniaturized device is referred to as micro Total Analysis Systems (&#956;TAS). Since its inception in 1990, the concept of &#956;TAS has relied on the use of micromachining technologies to fabricate fluidic components such as pumps, thermal reactors and mixers. One of the essential components of a &#956;TAS is a microfluidic device which separates a mixture of molecules in a biological sample for detection or further analyses by other components of the &#956;TAS. This Ph.D. thesis has developed a silicon-based microfabricated separation device that can perform size-dependent double stranded deoxyribonucleic acid (dsDNA) separation such that it is also viable for integration into a &#956;TAS platform.The separation method used in this thesis is ion-pair reversed-phase (IP-RP) chromatography. Using this method, shorter dsDNA fragments are less retained by the stationary phase than longer ones and thus migrate faster. This results in a truly size-dependent separation, in terms of the number of base pairs (bp). The microfabricated separation device developed in this thesis is a silicon-based microfabricated chromatography column, which is called a micro-pillar array column. This column format is not only suitable for µTAS but is also promising for great separation performance because of its highly ordered pillar structures.Silicon micro-pillar array columns have been fabricated using Deep-UV (DUV) lithography and the Bosch etch process. IP-RP chromatography has separated dsDNA fragments in a length range from 10 to 500bp in the Si micro-pillar array columns. Two separation modes, namely isocratic and gradient, have been studied in the thesis. In the isocratic mode, the separation time was very short, from several minutes down to a few seconds and separation of up to seven dsDNA fragments was achieved. In the gradient mode, up to 11 dsDNA fragments were separated and the analysis times ranged from less than 10 minutes to 1 hour. The resolution was very high as fragments differing of 8% of their lengths could be separated. These separations had a high reproducibility and a typical standard deviation of elution time among identical runs was only 2–3%. A systematic and extensive study on dsDNA retention behavior was successfully performed in the gradient mode. A theoretical model was established for describing dsDNA retention behavior based on the fragment length and the mobile phase gradient. By applying the modeling results in practice, controlling dsDNA retention time and determining dsDNA length on chip have been demonstrated.

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