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Mechanical Engineering. 2012;134(01):30-33. doi:10.1115/1.2012-JAN-2.
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This article explains how teardowns can help a company in arriving at a right manufacturing decision. Most poor decisions occur when people are starved for useful information. An understanding how lack of knowledge about product design and accounting undermines domestic-based production can help companies achieve globally competitive manufacturing sourced in home markets. Comparative teardowns have been performed for generations. The issue that prevents teardowns from reaching their full potential is that they are not performed with rigorous standardization. To compare teardowns efficiently, companies need a consistent methodology to capture, measure, and then communicate information effectively. Too often people tend to tear something apart, look at the pieces, and extract just a limited amount of the data. High-powered teardowns that consistently deliver results are carefully controlled. Moreover, the data is collected from such teardowns so that it can be easily accessed and analyzed, from the shop floor to the boardroom.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(01):36-39. doi:10.1115/1.2012-JAN-3.
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This article describes the design of steamboats during the first generation. The first generation of steamboat mechanics and engineers stuck to what they believed they could manage: low-steam engines with pressure gauges properly installed and monitored; single cylinders and moving parts that were kept continuously lubricated with tallow; boilers that were kept as air-tight as possible; and on the insides of those boilers, a periodic scraping and cleaning of any salt build-up, which became a bigger and bigger problem as steamboats ventured into saltier waters along the East Coast. As this wonderful new technology continued to expand into new territories, its true believers concluded that more powerful engines were needed. In the early 1820s, there was increased experimentation with two-cylinder engines and high-pressure boilers, both of which served to give steam-powered vessels the strength and stamina they needed to push a larger hull over greater distances. With their increasing adoption through the 1820s, multi-cylinder high-pressure steam engines marked the end of the first family of steam vessels, and the beginning of the next generation.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(01):40-43. doi:10.1115/1.2012-JAN-4.
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This article presents an overview of a turbine that uses supercritical carbon dioxide (CO2) to deliver great power. At around 73 atmospheres and roughly room temperature, CO2 makes a strange transition from a gas to a state known as a supercritical fluid. A supercritical fluid is dense, like a liquid, but it expands to fill a volume the way a gas does. These properties make supercritical CO2 an incredibly tantalizing working fluid for Brayton cycle gas turbines. Such gas turbine systems promise an increased thermal-to-electric conversion efficiency of 50% over conventional gas turbines. The system is also very small and simple, meaning that capital costs should be relatively low. The plant uses standard materials like chrome-based steel alloys, stainless steels, or nickel-based alloys at high temperatures (up to 800°C). It can also be used with all heat sources, opening up a wide array of previously unavailable markets for power production. For these reasons, the technology is quite promising.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(01):44-47. doi:10.1115/1.2012-JAN-5.
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This article discusses the advancement in bioprinting technology that would enable three-dimensional printing of living organs for transplant. Today, artificial or replacement tissue is commonly grown on collagen scaffolds that contain biological starter cells. The goal here is the growing of a biocompatible piece of tissue to repair or replace a patient’s own damaged body part, such as bone, cartilage, blood vessels, or skin. In future, bioprinting technology will allow making living organs for transplant. The method is much the same as additive manufacturing, in which a printer deposits a material, layer by layer, until a three-dimensional object is made. For bioprinting, the material used is likely to be living cells taken directly from the patient’s body and infused into an ink or gel to keep them alive. After printing, the material is incubated in a cell culture that mimics human body conditions until it fuses or becomes otherwise usable for implant.

Commentary by Dr. Valentin Fuster

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