As distance learning and computer based training become more popular, it is of great interest to measure if students are attentive to prerecorded lessons. This research was motivated by this interest, as well as recent advances in the use of biometric signal analysis for the detection of affective (emotional) response. This research extends these advances by creating a system which automatically and continuously measures attentiveness using light, dry, single electrode EEG. The results are promising. Using 56 participant individual cross validation, the method yielded 85% accuracy in identifying whether the person is watching a segment of video from a boring scene or lecture, versus a segment of video from an attentiveness inducing one. In addition, the final system produces an ensemble average of attentiveness across many participants, pinpointing areas in the training videos that induce peak attentiveness. Qualitative analysis of the results of this research are also very promising. The attentiveness graphs produced for individual participants correlate with the thoughts and feelings those participants had during different parts of the videos, as described in their own words.
This book answers the fundamental question of how to characterize and overcome the drawbacks associated with optical communication links that suffer from various types of fading when optical signals with information traverse these wireless (atmospheric) or wired (fiber optic) channels. The authors present material to help the reader predict the capacity, data rate, spectral efficiency, and bit-error-rate (BER) associated with a channel that experiences fading. It also presents modulation techniques and methods of coding and decoding that are useful when implementing communications systems. The book discusses how to model the channels, including treating distortion due to the various fading phenomena. Light waves and their similarity to radio waves are described, and the way light propagates through the atmosphere, through materials, and through the boundary between two materials is explained. This book also presents modulation techniques and methods of coding and decoding that are useful when implementing communications systems.
Solarzellen sind gefragt wie nie. Marktführer ist nach wie vor die Solarzelle aus kristalinem Silizium. Der Rohstoff Silizium wird jedoch aufgrund der großen Nachfrage immer teurer. Eine gute Alternative dazu sind Dünnschichtsolarzellen aus CIGS (CuInGaSe2) wegen des geringen Rohstoffgebrauchs und der hohen erzielten Wirkungsgrade. Neben einer hohen Effizienz werden an Solarzellen hohe Anforderungen an die Langzeitstabilität gestellt. Testverfahren, die Aussagen über das Langzeitverhalten liefern, müssen die Besonderheiten der verwendeten Materialien berücksichtigen. Im Folgenden werden deshalb automatisierte Testverfahren und Möglichkeiten der elektrischen Charakterisierung von CIS-Dünnschichtsolarzellen vorgestellt. Die Diplomarbeit besteht aus dem Erstellen eines geeigneten Testaufbaus, der Entwicklung von bestimmten Testverfahren zur Qualifikation der Solarzellen und der Auswertung dieser Tests. Schwerpunkte sind: Automatisierung, Lebensdauer bzw. Langzeitverhalten, Light soaking, Durchbruchverhalten, Elektrische Simulation eines Moduls
This book outlines the underlying principles on which interior lighting should be based, provides detailed information on the lighting hardware available today and gives guidance for the design of interior lighting installations resulting in good visual performance and comfort, alertness and health. The book is divided into three parts. Part One discusses the fundamentals of the visual and non-visual mechanisms and the practical consequences for visual performance and comfort, for sleep, daytime alertness and performance, and includes chapters on age effects, therapeutic effects and hazardous effects of lighting. Part Two deals with the lighting hardware: lamps (with emphasis on LEDs), gear, drivers and luminaires including chapters about lighting controls and LEDs beyond lighting. Part Three is the application part, providing the link between theory and practice and supplying the reader with the knowledge needed for lighting design. It describes the relevant lighting criteria for good and efficient interior lighting and discusses the International, European and North American standards and recommendations for interior lighting. A particular focus is on solid state light sources (LEDs) and the possibility to design innovative, truly-sustainable lighting installations that are adaptable to changing circumstances. The design of such installations is difficult and the book offers details of the typical characteristics of the many different solid state light sources, and of the aspects determining the final quality of interior lighting. Essential reading for interior lighting designers, lighting engineers and architects, the book will also be a useful reference for researchers and students. Reviews of Road Lighting by the same author: ´´If you are going to design streetlighting, you must read this book....a solid, comprehensive textbook written by an acknowledged expert in the field - if you have a query about any aspect of streetlighting design, you will find the answer here.´´ - LUX, August 2015 ´´...a realy comprehensive book dealing with every aspect of the subject well...essential text for reference on this subject´´ - Lighting Journal, March 2015
Want to learn even more about electronics in a fun, hands-on way? If you finished the projects in Make: Electronics, or if you´re already familiar with the material in that book, you´re ready for Make: More Electronics. Right away, you´ll start working on real projects, and you´ll explore all the key components and essential principles through the book´s collection of experiments. You´ll build the circuits first, then learn the theory behind them! This book picks up where Make: Electronics left off: you´ll work with components like comparators, light sensors, higher-level logic chips, multiplexers, shift registers, encoders, decoders, and magnetic sensors. You´ll also learn about topics like audio amplification, randomicity, as well as positive and negative feedback. With step-by-step instructions, and hundreds of color photographs and illustrations, this book will help you use -- and understand -- intermediate to advanced electronics concepts and techniques.
Want to know how to use an electronic component? This first book of a three-volume set includes key information on electronics parts for your projects - complete with photographs, schematics, and diagrams. You´ll learn what each one does, how it works, why it´s useful, and what variants exist. No matter how much you know about electronics, you´ll find fascinating details you´ve never come across before. Convenient, concise, well-organized, and precise Perfect for teachers, hobbyists, engineers, and students of all ages, this reference puts reliable, fact-checked information right at your fingertips - whether you´re refreshing your memory or exploring a component for the first time. Beginners will quickly grasp important concepts, and more experienced users will find the specific details their projects require. Unique: the first and only encyclopedia set on electronic components, distilled into three separate volumes Incredibly detailed: includes information distilled from hundreds of sources Easy to browse: parts are clearly organized by component type Authoritative: fact-checked by expert advisors to ensure that the information is both current and accurate Reliable: a more consistent source of information than online sources, product datasheets, and manufacturer´s tutorials Instructive: each component description provides details about substitutions, common problems, and workarounds Comprehensive: Volume 1 covers power, electromagnetism, and discrete semi-conductors; Volume 2 includes integrated circuits, and light and sound sources; Volume 3 covers a range of sensing devices.
Design custom printed circuit boards with EAGLE Learn how to make double-sided professional-quality PCBs from the ground up using EAGLE--the powerful, flexible design software. In this step-by-step guide, electronics guru Simon Monk leads you through the process of designing a schematic, transforming it into a PCB layout, and submitting standard Gerber files to a manufacturing service to create your finished board. Filled with detailed illustrations, photos, and screenshots, Make Your Own PCBs with EAGLE features downloadable example projects so you can get started right away. Install EAGLE Light Edition and discover the views and screens that make up an EAGLE project Create the schematic and board files for a simple LED project Find the right components and libraries for your projects Work with the Schematic Editor Lay out PCBs with through-hole components and with surface mount technology Build a sound level meter with a small amplifier and ten LEDs Generate Gerber design files to submit for fabrication Solder through-hole PCBs and SMD boards Design a plug-in Arduino shield Build a Raspberry Pi expansion board Automate repetitive tasks using scripts and User Language Programs Create your own libraries and parts and modify existingcomponents