Optical wireless based on high brightness visible LEDs

This paper is on a novel use of lighting or signaling devices constructed by light-emitting diodes (LEDs). The idea is on their concurrent use for simultaneous signaling and communications. The visible light from LEDs can be modulated and encoded with audio or data signal. Hence, an LED indicator lamp or traffic light can become an information broadcasting device. Such a system made up of high brightness visible LEDs can provide the function of open space, wireless broadcasting of audio or data signal. An implemented system with experimental results is shown. A portable receiver is designed to demodulate the optically transmitted information. The distance for audio transmission of an LED traffic light can reach over 20m. The optical link employs intensity modulation with direct detection. The system is limited to line-of-sight communications. However, this concurrent use of LEDs will open up many new applications.published_or_final_versio

LED wireless

High-brightness light-emitting diodes (LEDs) are getting more popular and are opening up a number of new applications. In this paper, the novel idea based on the fast switching of LEDs and the modulation of visible light is developed into a new kind of information system. A visible-LED audio system that makes use of visual-light rays to transmit audio messages to a remotely located receiver is described. Such a system made up of high-brightness visible LEDs can provide the function of open space, wireless broadcasting of audio signals. It can be used as an information beacon for short-distance communication.published_or_final_versio

City Tells:

City Tells. Guidelines to an Emotional Wayfinding System were developed to provide wayfinding information to visitors walking through historic environments and to ensure that unknown urban places become more welcoming, easier to navigate and more enjoyable for both visitors and tourists

Infrared Image Enhancement Using Wavelet Transform

In Infrared Image Enhancement using Wavelet Transform, two enhancement algorithms namely spatial and spatiotemporal homomorphic filtering (SHF and STHF) have been given for enhancement of the far infrared images based upon a far infrared imaging model. Although spatiotemporal homomorphic filtering may reduce the number of iterations greatly in comparison to spatial one for a similar degree of convergence by making explicit use of the additional information provided temporally, the enhanced results from SHF are in general better than those from STHF. In this dissertation work an additive wavelet transform will be proposed for enhancement and filtration of homomorphic infrared images. Keywords: Infrard Images, Additive Wavelet transform, Homomorphic Image Enhancement

Remote monitoring and security of covered bridges in the United States

The design, construction and use of covered timber bridges is all but a lost art in these days of prestressed concrete, high performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places and/or the diligent maintenance and care of the owners of these structures. Of the covered timber bridges that remain in the United States, only a small percentage still stand today due to arson, vandalism, neglect, and other factors. The objective of this work is to provide covered timber bridge owners with the ability to quickly and efficiently design and implement a security system to protect these important historical landmarks. This goal was obtained with an in-depth analysis of equipment selected by the design team based on the practicality in a covered bridge application. Other major considerations that are required for all equipment to work efficiently within a security system are also fully discussed, including, but not limited to, maintenance, power requirements, and general set-up of an integrated security system. To further guide bridge owners and engineers, a decision making tool is presented to expedite the selection process based on financial abilities and security expectations of the covered bridge owner. Possible sources of funding for security projects are discussed including the requirements and benefits of a bridge being placed on the National Register of Historic Places. A comprehensive case study is presented involving monitoring systems placed on five of the six covered bridges in Madison County, Iowa at the end of this thesis to showcase the abilities of an integrated system and all the decisions that must be made throughout the process for the entire system to work as intended. The creative component portion of this thesis is satisfied with the installation of the monitoring system in Madison County, Iowa, with emphasis on the renewable energ