Advanced Materials Research Vols. 622-623

Abstract: This brief communication proposes reasons for why larger β-sheet nanocrystals in spider silk exhibit lowered toughness as a function of increasing lateral size, but higher toughness as the β-strands are lengthened. Herein, this phenomenon is understood to be due to β-sheet stacking and the non-linear decreases in the electrostatic forces of attraction between β-sheets as more sheets are conjoined to form the crystal. Lengthening the β-strands raises the crystal toughness as a result of heightened electrostatic forces of attraction between the sheets. The extent of β-sheet nanocrystal toughness is a fractional balance between inter- and intramolecular bond strengths.

Abstract: The application of microgrippers for handling and assembling micro parts in the field of robotics attracts more attention by the growth in micro electro mechanical systems. In this paper an electrostatic microgripper using comb drive is designed and analyzed using IntelliSuite. The use of modified fingers in the combdrive amplifies the output displacement of microgripper for given supply voltage. It also provides a linear force displacement behavior over a range of displacement. To show this amplification, finite element simulations are performed on the proposed design of microgripper models. It was found that displacement of about 7 µm has been obtained at a voltage of 14 volts with 28 fingers only with one of the proposed designs of microgripper against 25 volts for rectangular finger microgripper with 28 fingers. The simulation results have been verified by analytical results. The results of analytical and simulation are found to be in good agreement.

Abstract: Dynamic production scheduling (DPS) is usually trigged by uncertain disturbances such as emergency orders, machine breakdown and rolling planning horizon etc. DPS is a challenging problem in real-life industry manufacturing field due to its bulky problem scalability, which is more significant in discrete manufacturing industry. This industry features multi-specifications, small batch and customization production pattern in terms of its production characteristics and workshop scheduling algorithm whose multi-product series are subject to complexity, multi- various constrains, multi-dynamic objectives and uncertainties. In order to card this research direction, this paper reviews it given different disturbances including emergency orders, machine breakdown, tardiness of job, and engineering changes. Moreover, currently common advantages and disadvantages of dynamic scheduling algorithm are laid stress on. Accordingly, characteristics and future research direction of it are presented. For different disturbances, corresponding algorithm solutions are categorized and reviewed. It aims at guiding the academics and practitioners to choose the efficient and effective solutions when facing different situations.

Abstract: This paper presents the effect of squeeze motion to elastohydrodynamic lubrication (EHL) in piston pin of air compressor with non-Newtonian lubricants based on a Carreau viscosity model. The time dependent modified Reynolds equation and elasticity with initial conditions were formulated and solved numerically using a multigrid multilevel with full approximation technique for a piston pin. Effects of bearing materials and liquid properties were examined. The results show that minimum film thickness and friction coefficient increases when lubricant viscosity increases. At the same time, for increasing of elastic modulus of bearing bushing the friction coefficient decreases.

Abstract: We theoretically investigate the nonequilibrium density of states (DOS) of a Kondo dot weakly coupled to Luttinger liquid leads by using the equation-of-motion technique of non-equilibrium Green functions. The joint effects of large bias voltage and moderately strong intralead interactions results in nontrivial modifications of the Kondo peak in the DOS. The DOS exhibits a two-channel Kondo physics for moderately strong interaction in the leads at zero temperature.

Abstract: Power quality has become an increasingly important topic in the performance of many industrial applications. One of the major issues in improving power quality in distribution networks is the mitigation of voltage sags. Voltage sag can be mitigated by voltage and power injections into the distribution system using Dynamic Voltage Restorer (DVR). The DVR is a powerful controller that is commonly used for voltage sags mitigation at the point of connection. This paper describes of modeling and analysis of DVR. Different types of faults are applied for DVR in distribution network and the responses of the system for these disturbances are examined. Simulation results obtained in PSCAD/EMTDC also prove that the DVR can mitigate voltage sag and protect bus bar voltage from various types of faults.

Abstract: The improvement of the energy efficiency of buildings calls for the availability of tools for evaluating and simulating the thermal behaviour of buildings, needing as input climatic databases. These databases contain a very large amount of data, resulting in long computational time analysis. Therefore, simple aggregation methods are used, among which the test reference year (TRY). In this paper, a comparison between two statistical methodologies for compiling a TRY, the Belgian and the Sandia methods, is presented. Then, the two methods have been utilized for compiling the TRY for the town of Palermo, Italy, and compared both statistically and by means of two simple applications, obtaining quite different results. Thus, a particular caution in the choice of the method for generating such reduced sets of data is suggested.

Abstract: Currently, battery management system is one of the attraction research topics in the battery management technologies. This paper researches a battery management system based on RS232 and Ethernet, which provides the managers manage the remote batteries in the comfortable and large office. It greatly betters the workers working environment and lights the labor strength. Arm as the kernel of the management system, which is programmed by the real-time operate system uc/os. Through analyzing the requirement of the battery management, hardware system and software system are designed by the thought of layering. The layering thought builds the management system, which can be amended to adapt to the other management. It provides the flexible for the battery management system.

Abstract: Nowadays the market is increasingly demanding more customized products, thus making the manufacturers under the pressure of cost reduction, to survive in the highly competitive market. Working on this, Robert Bosch INdia (RBIN) Limited, Bangalore Plant (BanP) designs and produces Diesel systems which make vehicles more cleaner and economical. To be the world’s leading manufacturer of diesel injection systems, Bosch has to manufacture its very own design to fulfill the requirements for every customers, economically. Fuel Injection Equipment in diesel engine is the “Heart of the Engine” and plays a major role in its performance, emissions and reliability. Hot Forged Rail (HFR) finds its application in common rail fuel injection system, which stores the fuel at high pressure (1600bar). And at the same time, the pressure oscillation, which is generated due to the high pressure pump delivery and the injection of fuel are damped by the rail volume. Its design varies according to customer requirement and engine design. Therefore, BanP has to produce different types of rails to complete diesel market in India. In order to be customer centric and productive, BOSCH follows Bosch Production Systems (BPS), the elements of BPS in Lean manufacturing are Value Stream Mapping (VSM), Value Stream Design (VSD) and Value Stream Planning (VSP). The Single Minute Exchange of Die (SMED) is one important lean manufacturing tool to reduce waste and improve production flexibility, allowing lot size reduction and manufacturing flow improvements. Quick Change Over (QCO) is a set of activities (preparation, changing and adjustment) which are being carried out in between the production of two varieties to reduce changeover time and to reach the optimum production running. The proposed SMED approach was tested for injection machines changeovers in the automotive industry and the implementation had enabled reduction in setup time, through company’s internal resources reorganizations without the need for significant investment. The objective of the present study is to implement the SMED/QCO tool approach in RBIN, BanP, HFR production line to reduce the changeover time by >65% and improve availability by 15%, thereby eliminating the possibility of investing on new production line to meet customer demand.

Abstract: Combined with the characteristics of the power grid construction projects, based on the fishbone diagram theory, the paper gradually identifies the cost risk factors in power grid construction projects according to the project construction process of project decision-making and feasibility study phase, design and bidding phase, construction phase,and completion of final accounts and summary evaluation phase. The study provides a certain amount of reference for power grid construction project risk management and controlling grid construction costs.