Many people just take for granted that something is just going to work, and in many cases assume that it will work forever. One such device that does not get enough attention is the Ground Fault Circuit Interrupter (GFCI). Simply put, a GFCI is a protective device that compares the current flowing on the hot and neutral wires of the circuit and will "trip" to disconnect power to the circuit if a small imbalance of current is detected. The imbalance of current is an indication of a dangerous alternate path for the current to flow from a damaged line cord or a fault inside an appliance and constitutes a shock hazard to a person.
The feasibility of two-beam speckle interferometry for the study of time-varying mechanical deformation of diffusely reflecting bodies is demonstrated. A sequence of speckle patterns produced by a vibrating cantilever beam was recorded photographically by means of a high-speed camera. These speckle photographs were subsequently digitized using a CCD camera for input into an image processing computer. By gray-level subtraction of carefully registered pairs of speckle images, fringes corresponding to the relative surface displacements were obtained. A sequence of these fringe patterns was reconstructed to obtain the time-history of deformation. These are compared with time-frozen (strobed) patterns for the same body.
A gray level transformation is presented to simulate the interferometric process. The transformation uses properties of sinusoidal functions to produce rapidly varying intensities from those with nearly zero gradients. The transformation when used in conjunction with optical techniques, such as holographic interferometry, has the effect of increasing the optical sensitivity and producing a large number of fringes where otherwise only a fraction of a fringe would be observed. This technique is ideal for holographic analysis of deformations in microscopic regions.
An In-Vehicle Data Acquisition/Monitoring Device (Data Logger) has been developed to be used for evaluating the performance of alternators during vehicle operation. It can be linked to other controllers and electronic devices for exchange of information through the use of a serial communication port. By utilizing a microcontroller, eight analog and three TTL level signals are measured and recorded in non-volatile EEPROM memory devices. The system measures temperatures of critical components, system voltage and rotational speed.
When I was a boy, playing in the sandbox or building with blocks, I dreamed of building cities. I feel fortunate to be in a profession which allows me to fulfill that dream. To enjoy your job is a more important measure of success than the amount of money in your bank account. My favorite definition of success is borrowed from Ann Landers:
The nursery rhyme involving Humpty Dumpty is a child's first lesson in safety. What would keep Humpty Dumpty safe as he is sitting on the wall? A warning or a railing?
Too frequently an attorney will begin to seek a potential expert witness only after having done considerable initial work. Often there is a last minute rush to locate and select specialized technical assistance. These approaches can have expensive consequences. Alternatively, securing a suitable expert early in the litigation process offers the following advantages for the retaining attorney:
Many negative consequences can result from failures of a range of different products that often lead to property & casualty insurance disputes or product liability legal actions. The products may include consumer or industrial goods. Typically the private user or worker is injured or a business incurs significant financial loss. The injured individual, insurance carrier, attorney(s) or industrial manufacturer and user are all interested to confirm what went wrong – and who is liable. Resolution often depends on engineering analysis.
Hand washing with soap is a practice that has long been recognized as a major barrier to the spread of disease in food production, preparation, and service and in health care settings, including hospitals, child care centers, and elder care facilities. Many of these settings present multiple opportunities for spread of pathogens within at-risk populations, and extra vigilance must be applied. Unfortunately, hand hygiene is not always carried out effectively, and both enteric and respiratory diseases are easily spread in these environments. Where water is limited or frequent hand hygiene is required on a daily basis, such as for many patients in hospitals and astronauts in space travel, instant sanitizers or sanitary wipes are thought to be an effective way of preventing contamination and spread of organisms among coworkers and others. Most concerns regarding compliance are associated with the health care field, but the food industry also must be considered.
A licensed professional engineer (P.E.) is required to adhere to a Code of Ethics for Engineers in all work he undertakes. However, there are some special criteria when employed as an expert witness.