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In this work, aluminum/titanium carbide (Al/TiC) surface composite has been fabricated by friction stir processing using a novel modular Direct Particle Injection Tool (DPI–FSP). The tool has a unique feature wherein the TiC particles have been transferred from the tool itself by spring adjusted plunger movement into the matrix. The microstructural observations from optical and scanning electron microscope (SEM)-EDS results revealed the homogeneous distribution of particles in the stirred zone (SZ) and the thickness of the formed surface composite layer (SCL) is approximately 0.34mm. X-ray diffraction results confirmed that the particles are reinforced in the aluminum matrix, and no intermetallics have been formed in the composite. The microhardness of composite was increased from 68 to 135Hv, and the impact test results showed that the toughness was almost comparable to that of the base metal.

The controlling method for high-voltage pulse form or pulse parameter is extremely important in high speed switching technique. Function generation can repeatedly make various forms and widths of pulse waves such as low-voltage sine wave, square wave, and sawtooth wave. Waveform control is not easy when voltage exceeds a certain amount of kVs. Pulse forming network (PFN) or pulse forming line (PFL) has been used so far along with trigger gap, rail gap, semiconductor switch, ignitron, cyratron, and autocompression switch, which are used as switching device. For PFN, multistep LC circuit is introduced to widen the pulse width, and for PFL, a method to lengthen the charging line is adopted. These methods are difficult to control because a large number of devices are used, and the devices are getting bigger in terms of size. In order to compensate this weakness, the researchers of this study made self-stimulating pulse forms with various pulse widths by actively engrafting the low-voltage two-step or four-step circuits with the AVR one-chip microprocessor technology, which is widely used for two-step or four-step electric network recently with low price.

This chapter discusses some key themes and issues in relation to IT offshore outsourcing. In particular it provides an analysis of four U.K. based companies undertaking IT offshore outsourcing projects. Each company represents an example of different approaches to outsourcing. These approaches are argued to represent more than just approaches and that they are in fact significantly different business models. The four different models are: (i) direct offshore outsourcing, (ii) third party offshore outsourcing, (iii) joint venture offshore outsourcing, and (iv) wholly owned subsidiary. These approaches highlight the heterogeneous nature of the offshore outsourcing phenomenon. A framework is then proposed based on the literature and the study which provides four important elements and related subfactors of interest and importance. This framework is then used to analyze the cases, highlighting some of the drivers and risk factors of the models for decision making from the customer’s perspective.

The traditional direct cooling refrigerators are widely used because of its low power consumption, low noise, low price, refrigerated food freshness higher advantages. But direct cooling refrigerators have a fatal problem, that is, evaporator frosting problem. Direct cooling refrigerator evaporator frosting will seriously affect the refrigeration efficiency and the service life of the refrigerator. With an accumulation of frost refrigerator, refrigerating efficiency can reduce 20%-30%, which leads to the great waste of electricity. This design is put forward by using mechanical reciprocating defrosting method realization to periodic direct cooling refrigerator evaporator in the intelligent control of the automatic defrosting work, to improve the refrigeration efficiency of the refrigerator and the use of performance, prolong the service life are of great significance. Direct cooling refrigerator evaporator automatic defrosting device conforms to China's energy-saving low requirements.