Additive manufacturing processes take the information from a computer-aided design (CAD) file that is later converted to a stereolithography (STL) file. In this process, the drawing made in the CAD software is approximated by triangles and sliced containing the information of each layer that is going to be printed. There is a discussion of the relevant additive manufacturing processes and their applications. The aerospace industry employs them because of the possibility of manufacturing lighter structures to reduce weight. Additive manufacturing is transforming the practice of medicine and making work easier for architects. In 2004, the Society of Manufacturing Engineers did a classification of the various technologies and there are at least four additional significant technologies in 2012. Studies are reviewed which were about the strength of products made in additive manufacturing processes. However, there is still a lot of work and research to be accomplished before additive manufacturing technologies become standard in the manufacturing industry because not every commonly used manufacturing material can be handled. The accuracy needs improvement to eliminate the necessity of a finishing process. The continuous and increasing growth experienced since the early days and the successful results up to the present time allow for optimism that additive manufacturing has a significant place in the future of manufacturing.

Nanofluids are suspensions of nanoparticles in fluids that show significant enhancement of their properties at modest nanoparticle concentrations. Many of the publications on nanofluids are about understanding their behavior so that they can be utilized where straight heat transfer enhancement is paramount as in many industrial applications, nuclear reactors, transportation, electronics as well as biomedicine and food. Nanofluid as a smart fluid, where heat transfer can be reduced or enhanced at will, has also been reported. This paper focuses on presenting the broad range of current and future applications that involve nanofluids, emphasizing their improved heat transfer properties that are controllable and the specific characteristics that these nanofluids possess that make them suitable for such applications.

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Review of World Urban Heat Islands: Many Linked to Increased MortalityMedical and health researchers have shown that fatalities during heat waves are most commonly due to respiratory and cardiovascular diseases, primarily from heat's negative effect on the cardiovascular system. In an attempt to control one's internal temperature, the body's natural instinct is to circulate large quantities of blood to the skin. However, to peiform this protective measure against overheating actually harms the body by inducing extra strain on the heart. This excess strain has the potential to trigger a cardiac event in those with chronic health problems, such as the elderly, Cui et al. Frumkin showed that the relationship of mortality and temperature creates a J-shaped function, showing a steeper slope at higher temperatures. Records show that more casualties have resulted from heat waves than hurricanes, floods, and tornadoes together. This statistic's significance is that extreme heat events (EHEs) are becoming more frequent, as shown by Stone et al. Their analysis shows a growth trend of EHEs by 0.20 days/year in U.S. cities between 1956 and 2005, with a 95% confidence inten-al and uncertainty of ±0.6. This means that there were 10 more days of extreme heat conditions in 2005 than in 1956. Studies held from 1989 to 2000 in 50 U.S. cities recorded a rise of 5.7% in mortality during heat waves. The research of Schifano et al. revealed that Rome's elderly population endures a higher mortality rate during heat waves, at 8% excess for the 65-74 age group and 15% for above 74. Even more staggering is findings ofDousset et al. on French cities during the 2003 heat wave. Small towns saw an average excess mortality rate of 40%, while Paris witnessed an increase of 141%. During this period, a 0.5 °C increase above the average minimum nighttime temperature doubled the risk of death in the elderly. Heat-related illnesses and mortality rates have slightly decreased since 1980, regardless of the increase in temperatures. Statistics from the U.S. Census state that the U.S. population without air conditioning saw a drop of 32% from 1978 to 2005, resting at 15%. Despite the increase in air conditioning use, a study done by Kalkstein through 2007 proved that the shielding effects of air conditioning reached their terminal effect in the mid-1990s. Kan et al. hypothesize in their study of Shanghai that the significant difference in fatalities from the 1998 and 2003 heat waves was due to the increase in use of air conditioning. Protective factors have mitigated the danger of heat on those vulnerable to it, however projecting foi-ward the heat increment related to sprawl may exceed physiologic adaptation thresholds. It has been studied and reported that urban heat islands (UHI) exist in the following world cities and their countries and/or states: and Delhi, India. The strongest being Shanghai, Bangkok, Beijing,10, and 12 °C, respectively. Of the above world cities. Hong Kong, Bangkok, Delhi, Bangladesh, London, Kyoto, Osaka, and Berlin have be...

A new approach to determine aquifer parameter values from aquifer‐test data has been developed that uses the pattern‐matching capability of a neural network. The network is trained to recognize patterns of normalized drawdown data as input and the corresponding aquifer parameters as output. The Theis and Hantush‐Jacob solutions for confined and leaky‐confined aquifer conditions are used to derive the input patterns based on the parameter values selected from predetermined ranges. The trained network produces output of aquifer parameter values when it receives the aquifer‐test data as the input patterns. The results obtained from this new approach are in good agreement with published results using other techniques. The advantages of the present approach are the automated process of obtaining aquifer parameter values and the ability of the network to associate drawdown to the corresponding Theis and Hantush‐Jacob solutions.

Recent studies have showed that nanofluids have significantly greater thermal conductivity compared to their base fluids. Large surface area to volume ratio and certain effects of Brownian motion of nanoparticles are believed to be the main factors for the significant increase in the thermal conductivity of nanofluids. In this paper all three transport properties, namely thermal conductivity, electrical conductivity and viscosity, were studied for alumina nanofluid (aluminum oxide nanoparticles in water). Experiments were performed both as a function of volumetric concentration (3-8%) and temperature (2-50 °C). Alumina nanoparticles with a mean diameter of 36 nm were dispersed in water. The effect of particle size was not studied. The transient hot wire method as described by Nagaska and Nagashima for electrically conducting fluids was used to test the thermal conductivity. In this work, an insulated platinum wire of 0.003 inch diameter was used. Initial calibration was performed using de-ionized water and the resulting data was within 2.5% of standard thermal conductivity values for water. The thermal conductivity of alumina nanofluid increased with both increase in temperature and concentration. A maximum thermal conductivity of 0.7351 W m(-1) K(-1) was recorded for an 8.47% volume concentration of alumina nanoparticles at 46.6 °C. The effective thermal conductivity at this concentration and temperature was observed to be 1.1501, which translates to an increase in thermal conductivity by 22% when compared to water at room temperature. Alumina being a good conductor of electricity, alumina nanofluid displays an increasing trend in electrical conductivity as volumetric concentration increases. A microprocessor-based conductivity/TDS meter was used to perform the electrical conductivity experiments. After carefully calibrating the conductivity meter's glass probe with platinum tip, using a standard potassium chloride solution, readings were taken at various volumetric concentrations. A 3457.1% increase in the electrical conductivity was measured for a small 1.44% volumetric concentration of alumina nanoparticles in water. The highest value of electrical conductivity, 314 µS cm(-1), was recorded for a volumetric concentration of 8.47%. In the determination of the kinematic viscosity of alumina nanofluid, a standard kinematic viscometer with constant temperature bath was used. Calibrated capillary viscometers were used to measure flow under gravity at precisely controlled temperatures. The capillary viscometers were calibrated with de-ionized water at different temperatures, and the resulting kinematic viscosity values were found to be within 3% of the standard published values. An increase of 35.5% in the kinematic viscosity was observed for an 8.47% volumetric concentration of alumina nanoparticles in water. The maximum kinematic viscosity of alumina nanofluid, 2.901 42 mm(2) s(-1), was obtained at 0 °C for an 8.47% volumetric concentration of alumina nanoparticles. The experimental results of the present work wil...

Smart glass is such that its properties may he changed by application of a potential across it. The change in properties may be engineered to alter the amount of heat energy that can penetrate the glass which provides heating and cooling design options. Therein lies its potential in energy savings. Smart glass may be classified into three types: electrochromic, suspended particle, and polymer dispersed liquid crystal (PDLC). Each of these types has their own mechanisms, advantages, and disadvantages. Electrochromic smart glass is the most popular, currently it utilizes an electrochromic film with an ion storage layer and ion conductor placed between two transparent plates. The electrochromic film is usually made of tungsten oxide, owing to the electrochromic nature of transition metals. An electric potential initiates a redox reaction of the electrochromic film transitioning the color and the transparency of the smart glass. Suspended particle smart glass has needle shaped particles suspended within an organic gel placed between two electrodes. In its off state, the particles are randomly dispersed and have a low light transmittance. Once a voltage is applied, the needle particles will orient themselves to allow for light to pass through. PDLC smart glass works similarly to the suspended particle variety. However, in PDLC smart glass, the central layer is a liquid crystal placed within a polymer matrix between electrodes. Similar in behavior to the suspended particles, in the off position the liquid crystals are randomly dispersed and have low transmittance. With the application of a voltage, the liquid crystals orient themselves, thereby allowing for the transmittance of light. These different smart glasses have many different applications, but with one hindrance. The requirement of a voltage source is a major disadvantage which greatly complicates the overall installation and manufacturing processes. However, the integration of photovoltaic (PV) devices into smart glass technology has provided one solution. Photovoltaic films attached in the smart glass will provide the necessary voltage source. The photovoltaic film may even be designed to produce more voltage than needed. The use a photovoltaic smart glass system provides significant cost savings in regards to heating, cooling, lighting, and overall energy bills. Smart glass represents a technology with a great deal of potential to reduce energy demand. Action steps have been identified to propagate the popular use of smart glass.

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