Theoretical review in optical materials used in Concentrating Dissertation

Theoretical review in optical materials used in Concentrating Photovoltanic (CPV) Technology - Dissertation Example Photovoltaic cells have been widely in use for the production of electricity from solar energy. However, they have high production costs because of which the cost of photovoltaic electricity is high, causing difficulties in their widespread use and market penetration (Swanson, 2000). One approach through which this drawback can be minimized is the use of solar concentrators that can increase solar irradiation per unit area of the solar cells, thereby resulting in increased electricity production per unit area of the receiver (Abdul-Rahman & Wang, 2010). Apart from increasing the electricity efficiency of the photovoltaic solar cells, the use of solar concentrators can also help in decreasing the area required for a given amount of output. Concentrating photovoltaic (CPV) technology uses optical components as solar concentrators. This technology is economically advantageous as it helps in decreasing the cost of solar electricity by using optical material that is less expensive than ph otovoltaic cells, resulting in the need for lesser number of solar cells for the same electrical output. Thus, in simpler words, the goal of CPV technology is to â€Å"reduce the cost of electricity generated by replacing expensive PV converter area with less expensive optical material† (Swanson, 2003, p. 449). ... ectric Fresnel lenses, other types of solar concentrators include dish concentrators, compound parabolic concentrators, and reflectors (Brogren, 2004). As the present study aims at modeling optical parameters for optimum collection of concentrated solar radiation for photovoltaic devices, this theoretical review will focus on the different types of optical materials used in CPV technology. Apart from providing a brief overview of the types of solar concentrators, their optics, and the types of optical materials used, this review will also elaborate the optical and physical properties of optical materials, especially glass and polymeric materials such as poly (methyl methacrylate) (PMMA), which are relevant to the present study. 2.2. Solar Concentrators & Their Types Solar concentrators are of various types depending on the type of optics employed, the concentration ratio, the number of axes for tracking the sun, etc. Fig. 2.2. Schematic representation of solar concentrator, radiation intercepted by the aperture area, A1, falls on the receiver area, A2 (Brogren, 2004, p. 41). The figure 2.2 above shows the diagrammatic representation of a solar concentrator that concentrates solar radiation spread over a wider aperture area, A1, over a smaller receiver area, A2. 2.2.1. Concentration Ratio The geometric concentration ratio of a given concentrating system is the ratio of the concentrator aperture area and area over which the radiation is concentrated. It is given by the following equation: Cg = A1/A2, where, Cg = geometric concentration ratio, A1 = â€Å"aperture area of concentrator†, and A2= â€Å"area onto which the radiation is concentrated† (Brogren, 2004). For solar concentrators, the geometric concentration ratio is defined as â€Å"the area of the primary lens or

Nursing Practice in Context 4 Assignment Example | Topics and Well Written Essays - 2000 words

Nursing Practice in Context 4 - Assignment Example When the body digests proteins, there is usually the generation of waste products. These wastes become part of urine. Diabetes destroys the tiny blood vessels and holes, which act as filters when they are overburdened (Bruce & Paxton, 2008). After some years, the filters will stop functioning properly and some of the important proteins will leak into urine causing a condition called micro albunuria (American Diabetes Association, 2006). The initial symptom of the chronic diseases is the buildup of fluids at various body parts. Other signs entail insomnia, loss of appetite, and lack of concentration (American Diabetes Association, 2012).Chronic kidney disease (CKD) leads to premature mortality, low quality of life, and high life expenditures. Different diseases such as diabetes, hypertension and obesity have played greater roles in the increase of chronic kidney diseases (Bruce & Paxton, 2008). The research indicated that obesity relates with diabetes and hypertension and the three ar e the major leading causes of chronic kidney diseases. In U.S, the numbers of adults with obesity have been doubling for the past three-decade (Bruce & Paxton, 2008). ... It will not rely on whether an individual looses weight through maintaining diet, exercising or undergoing bariatric surgery. The conducted studies reveals that weight loss reduces the rates of hypertension, type 2 diabetes and obesity. People should ensure that they maintain their diet and exercise in order to lose weight as it will help them in reducing the rates of obesity, hypertension, and diabetes (McBride & Korczak, 2007). Question 2 (B) The paper highlights the nursing care of Mrs. Mrs. Douglas Douglas who is 74 years old. She is a diabetic with many complications and she is admitted for surgery tomorrow. The two nursing problems that Mrs. Douglas has are nutritional deficit and electrolyte imbalance. She also has impaired skin integrity. The two nursing interventions explained in the paper are the acute and community care focus. Two evaluation criteria for each intervention will also be explained Priority Problem 1 Nutritional deficit and fruit imbalance One of the identifie d medical problems entails nutritional deficit and fluid imbalance. Mrs. Douglas is experiencing these problems because of her poor nutritional habits and she does not know about the illness processes. The assessment data used to support this diagnosis is the subjective data of the patients’ nutritional habits. Mrs. Douglas stated that she takes 1-2 glasses of juice and water per day, lack of knowledge of what to eat or drink, and sometimes she lacks appetite because of the bad taste in her mouth. The objective data that supports the diagnosis entail obesity and kidney disease. These are caused by taking food with high cholesterol, not doing enough exercises, and failure to take enough