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Lithium niobate (LN), first synthesized 70 years ago, has been widely used in diverse applications ranging from communications to quantum optics. These high-volume commercial applications have provided the economic means to establish a mature manufacturing and processing industry for high-quality LN crystals and wafers. Breakthrough science demonstrations to commercial products have been achieved owing to the ability of LN to generate and manipulate electromagnetic waves across a broad spectrum, from microwave to ultraviolet frequencies. Here, we provide a high-level Review of the history of LN as an optical material, its different photonic platforms, engineering concepts, spectral coverage, and essential applications before providing an outlook for the future of LN.
Purpose Artificial intelligence (AI) chatbots, such as ChatGPT and GPT-4, developed by OpenAI, have the potential to revolutionize education. This study explores the potential benefits and challenges of using ChatGPT in education (or “educative AI”). Design/Approach/Methods This paper proposes a theoretical framework called “IDEE” for educative AI such as using ChatGPT and other generative AI in education, which includes identifying the desired outcomes, determining the appropriate level of automation, ensuring ethical considerations, and evaluating effectiveness. Findings The benefits of using ChatGPT in education or more generally, educative AI, include a more personalized and efficient learning experience for students as well as easier and faster feedback for teachers. However, challenges such as the untested effectiveness of the technology, limitations in the quality of data, and ethical and safety concerns must also be considered. Originality/Value This study explored the opportunities and challenges of using ChatGPT in education within the proposed theoretical framework.
Artificial Intelligence (AI)-based ChatGPT developed by OpenAI is now widely accepted in several fields, including education. Students can learn about ideas and theories by using this technology while generating content with it. ChatGPT is built on State of the Art (SOA), like Deep Learning (DL), Natural Language Processing (NLP), and Machine Learning (ML), an extrapolation of a class of ML-NLP models known as Large Language Model (LLMs). It may be used to automate test and assignment grading, giving instructors more time to concentrate on instruction. This technology can be utilised to customise learning for kids, enabling them to focus more intently on the subject matter and critical thinking ChatGPT is an excellent tool for language lessons since it can translate text from one language to another. It may provide lists of vocabulary terms and meanings, assisting students in developing their language proficiency with resources. Personalised learning opportunities are one of ChatGPT’s significant applications in the classroom. This might include creating educational resources and content tailored to a student’s unique interests, skills, and learning goals. This paper discusses the need for ChatGPT and the significant features of ChatGPT in the education system. Further, it identifies and discusses the significant applications of ChatGPT in education. Using ChatGPT, educators may design lessons and instructional materials specific to each student’s requirements and skills based on current trends. Students may work at their speed and concentrate on the areas where they need the most support, resulting in a more effective and efficient learning environment. Both instructors and students may profit significantly from using ChatGPT in the classroom. Instructors may save time on numerous duties by using this technology. In future, ChatGPT will become a powerful tool for enhancing students’ and teachers’ experience.
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New normal linear modeling strategies are presented for analyzing read counts from RNA-seq experiments. The voom method estimates the mean-variance relationship of the log-counts, generates a precision weight for each observation and enters these into the limma empirical Bayes analysis pipeline. This opens access for RNA-seq analysts to a large body of methodology developed for microarrays. Simulation studies show that voom performs as well or better than count-based RNA-seq methods even when the data are generated according to the assumptions of the earlier methods. Two case studies illustrate the use of linear modeling and gene set testing methods.
Nearly a century has been spent collecting and preserving genetic diversity in plants. Germplasm banks-living seed collections that serve as repositories of genetic variation-have been established as a source of genes for improving agricultural crops. Genetic linkage maps have made it possible to study the chromosomal locations of genes for improving yield and other complex traits important to agriculture. The tools of genome research may finally unleash the genetic potential of our wild and cultivated germplasm resources for the benefit of society.
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We recount some of the most significant and colorful findings of our four-year study of gender issues in the undergraduate computer science program at Carnegie Mellon. We also discuss the subsequent dramatic increase in the number of women in the program. We conclude with recommendations for the most generally useful and effective actions departments can take to attract and retain female students.
In irons bound: Linear diamine and formylpyridine subcomponents form a tetrahedral cage with iron(II) in water (see scheme). This cage traps hydrophobic guests with high specificity within a rigid cavity, isolating them from the aqueous environment. The cage may be broken, releasing the guest, upon the addition of a triamine. It may also be unlocked by adding acid, allowing the guest to be reversibly released until base is added, relocking it within.
We studied publication bias in the social sciences by analyzing a known population of conducted studies--221 in total--in which there is a full accounting of what is published and unpublished. We leveraged Time-sharing Experiments in the Social Sciences (TESS), a National Science Foundation-sponsored program in which researchers propose survey-based experiments to be run on representative samples of American adults. Because TESS proposals undergo rigorous peer review, the studies in the sample all exceed a substantial quality threshold. Strong results are 40 percentage points more likely to be published than are null results and 60 percentage points more likely to be written up. We provide direct evidence of publication bias and identify the stage of research production at which publication bias occurs: Authors do not write up and submit null findings.
Abstract New transportation fuels are badly needed to reduce our heavy dependence on imported oil and to reduce the release of greenhouse gases that cause global climate change; cellulosic biomass is the only inexpensive resource that can be used for sustainable production of the large volumes of liquid fuels that our transportation sector has historically favored. Furthermore, biological conversion of cellulosic biomass can take advantage of the power of biotechnology to take huge strides toward making biofuels cost competitive. Ethanol production is particularly well suited to marrying this combination of need, resource, and technology. In fact, major advances have already been realized to competitively position cellulosic ethanol with corn ethanol. However, although biotechnology presents important opportunities to achieve very low costs, pretreatment of naturally resistant cellulosic materials is essential if we are to achieve high yields from biological operations; this operation is projected to be the single, most expensive processing step, representing about 20% of the total cost. In addition, pretreatment has pervasive impacts on all other major operations in the overall conversion scheme from choice of feedstock through to size reduction, hydrolysis, and fermentation, and on to product recovery, residue processing, and co‐product potential. A number of different pretreatments involving biological, chemical, physical, and thermal approaches have been investigated over the years, but only those that employ chemicals currently offer the high yields and low costs vital to economic success. Among the most promising are pretreatments using dilute acid, sulfur dioxide, near‐neutral pH control, ammonia expansion, aqueous ammonia, and lime, with significant differences among the sugar‐release patterns. Although projected costs for these options are similar when applied to corn stover, a key need now is to dramatically improve our knowledge of these systems with the goal of advancing pretreatment to substantially reduce costs and to accelerate commercial applications. © 2007 Society of Chemical Industry and John Wiley & Sons, Ltd
When The Knowledge-Creating Company (OUP; nearly 40,000 copies sold) appeared, it was hailed as a landmark work in the field of management. Now, Enabling Knowledge Creation ventures even further into this all-important territory, showing how firms can generate and nurture ideas by using the concepts introduced in the first book. Weaving together lessons from such international leaders as Siemens, Unilever, Skandia, and Sony, along with their own first-hand consulting experiences, the authors introduce enabling-the overall set of organizational activities that promote creation-and demonstrate its power to transform an organization's into value-creating actions. They describe the five key enablers and outline what it takes to instill a vision, manage conversations, mobilize activists, create the right context for creation, and globalize local knowledge. The authors stress that creation must be more than the exclusive purview of one individual-or designated knowledge officer. Indeed, it demands new roles and responsibilities for everyone in the organization-from the elite in the executive suite to the frontline workers on the shop floor. Whether an activist, a caring expert, or a corporate epistemologist who focuses on the theory of itself, everyone in an organization has a vital role to play in making care an integral part of the everyday experience; in supporting, nurturing, and encouraging microcommunities of innovation and fun; and in creating a shared space where is created, exchanged, and used for sustained, competitive advantage. This much-anticipated sequel puts practical tools into the hands of managers and executives who are struggling to unleash the power of in their organization.
This study introduces and validates a measure of country institutional profile for entrepreneurship consisting of regulatory, cognitive, and normative dimensions. Subscales based on data from six c...
Nearly all high-energy density cathodes for rechargeable lithium batteries are well-ordered materials in which lithium and other cations occupy distinct sites. Cation-disordered materials are generally disregarded as cathodes because lithium diffusion tends to be limited by their structures. The performance of Li1.211Mo0.467Cr0.3O2 shows that lithium diffusion can be facile in disordered materials. Using ab initio computations, we demonstrate that this unexpected behavior is due to percolation of a certain type of active diffusion channels in disordered Li-excess materials. A unified understanding of high performance in both layered and Li-excess materials may enable the design of disordered-electrode materials with high capacity and high energy density.
Oxygen isotope records and glaciomarine sediments indicate at least an intermittent presence of large continental ice sheets on Antarctica since the earliest Oligocene (circa 35 Ma). The growth and decay of ice sheets during the Oligocene to modern “ice house world” caused glacioeustatic sea level changes. The early Eocene was an ice‐free “greenhouse world,” but it is not clear if ice sheets existed during the middle to late Eocene “doubt house world.” Benthic foraminiferal δ 18 O records place limits on the history of glaciation, suggesting the presence of ice sheets at least intermittently since the earliest Oligocene. The best indicator of ice growth is a coeval increase in global benthic and western equatorial planktonic δ 18 O records. Although planktonic isotope records from the western equatorial regions are limited, subtropical planktonic foraminifera may also record such ice volume changes. It is difficult to apply these established principles to the Cenozoic δ 18 O record because of the lack of adequate data and problems in stratigraphic correlations that obscure isotope events. We improved Oligocene to Miocene correlations of δ 18 O records and erected eight oxygen isotope zones (Oi1‐Oi2, Mi1‐Mi6). Benthic foraminiferal δ 18 O increases which are associated with the bases of Zones Oil (circa 35.8 Ma), Oi2 (circa 32.5 Ma), and Mil (circa 23.5 Ma) can be linked with δ 18 O increases in subtropical planktonic foraminifera and with intervals of glacial sedimentation on or near Antarctica. Our new correlations of middle Miocene benthic and western equatorial planktonic δ 18 O records show remarkable agreement in timing and amplitude. We interpret benthic‐planktonic covariance to reflect substantial ice volume increases near the bases of Zones Mi2 (circa 16.1 Ma), Mi3 (circa 13.6 Ma), and possibly Mi5 (circa 11.3 Ma). Possible glacioeustatic lowerings are associated with the δ 18 O increases which culminated with the bases of Zone Mi4 (circa 12.6 Ma) and Mi6 (circa 9.6 Ma), although low‐latitude planktonic δ 18 O records are required to test this. These inferred glacioeustatic lowerings can be linked to seismic and rock disconformities. For example, we link 12 Oligocene‐early late Miocene inferred glacioeustatic lowerings with 12 of the sequence boundaries (= inferred eustatic lowerings) of Haq et al. (1987).
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Mastering Bitcoin is essential reading for everyone interested in learning about bitcoin basics, the technical operation of bitcoin, or if you're building the next great bitcoin killer app or business. From using a bitcoin wallet to buy a cup of coffee, to running a bitcoin marketplace with hundreds of thousands of transactions, or collaboratively building new financial innovations that will transform our understanding of currency and credit, this book will help you engineer money. You're about to unlock the API to a new economy. This book is your key. This book will help you learn everything you need to know about decentralized digital money, which is one of the most exciting technical revolutions in decades. Just as the Internet has transformed dozens of industries - from media and entertainment to retailing, travel and many more - decentralized digital money, in the form of crypto-currencies, has the ability to transform the foundations of money, credit and financial services. It also has the power to transform other social activities and institutions that we don't usually associate directly with money, such as corporations, governance, voting and the law. As the first successful digital currency, bitcoin is the natural starting point for anyone interested in decentralized digital money, its implications and applications. Mastering Bitcoin describes the technical foundations of bitcoin and other cryptographic currencies, from cryptography basics, such as keys and addresses, to the data structures, network protocols and the consensus mechanism (mining) that underpin bitcoin. Each technical topic is explained with user stories, elegant analogies and examples, and code snippets illustrating the key concepts. The first two chapters offer a broad and accessible introduction to bitcoin that is intended for all audiences, from new non-technical users to investors and business executives seeking to better understand bitcoin. The remainder of the book dives into the technical details of bitcoin's operation and is aimed at professional developers, engineers, software and systems architects, systems administrators and technically-minded people interested in the inner workings of bitcoin and comparable crypto-currencies. Mastering Bitcoin is intended to be used as a reference book for technical professionals, as a self-study guide for bitcoin entrepreneurs, and as a textbook for university courses on bitcoin and digital currencies. Bitcoin is still in its infancy, and yet it has already spawned a multi-billion dollar, global economy that is growing exponentially. Both new and established companies are adding bitcoin as a payment method, and investors are funding a flurry of new bitcoin and related startups. Mastering Bitcoin can help you become part of this vibrant new economy. The time to get started is now.
From the last several years, in serious consideration of the worldwide economic and environmental pollution issues there has been increasing research interest in the value of bio-sourced lignocellulosic biomass. Agro-industrial biomass comprised on lignocellulosic waste is an inexpensive, renewable, abundant and provides a unique natural resource for large-scale and cost-effective bio-energy collection. To expand the range of natural bio-resources the rapidly evolving tools of biotechnology can lower the conversion costs and also enhance target yield of the product of interest. In this background green biotechnology presents a promising approach to convert most of the solid agricultural wastes particularly lignocellulosic materials into liquid bio based energy-fuels. In fact, major advances have already been achieved to competitively position cellulosic ethanol with corn ethanol. The present summarized review work begins with an overview on the physico-chemical features and composition of agro-industrial biomass. The information is also given on the multi-step processing technologies of agro-industrial biomass to fuel ethanol followed by a brief summary of future considerations.