Computerized facility layout design

The paper describes a computerized facility layout designer, COMLAD II, for plant layout development. Besides developing an efficient layout, COMLAD II has useful features which allow fixing the departments, changing the shape of the departments and changing the length and width dimensions of the overall layout.     

Purification and renaturation of recombinant human lymphotoxin (tumour necrosis factor beta) expressed in Escherichia coli as inclusion bodies

High level expression of recombinant human tumour necrosis factor β (rh TNF-β) in Escherichia coli results in the formation of two portions of protein, namely soluble active protein and insoluble protein which is inactive and aggregates in the form of inclusion bodies (IBs). In this study, a procedure for purification and renaturation of rh TNF-β from inclusion bodies has been designed and verified experimentally with a product purity of more than 90% and a recovery of about 30%. The procedure includes washing of IBs with specific wash buffer (Triton X-100/EDTA/lysozyme/PMSF), their solubilization with 8 mol dm^?3 alkaline urea, purification with ion-exchange columns, refolding with renaturation buffer and finally concentration and desalination with an ultrafiltration membrane. The characteristics of the renatured protein were identical with those of purified protein from the soluble fraction as demonstrated by (1) SDS-PAGE, (2) cytotoxic activity on mouse L929 cells, (3) N-terminal amino acid sequence, and (4) gel filtration chromatography.     

Electronic transport behavior of 4,6-bis(4-nitrophenyl)-2-phenyl-3,5-diaza-bicyclo[3.1.0]hex-2-ene (a bicyclic aziridine) as optical molecular switch: a first-principles approach

Journal of Computational Electronics - In this study, the electronic transport properties of 4,6-bis(4-nitrophenyl)-2-phenyl-3,5-diaza-bicyclo[3.1.0]hex-2-ene (as a bicyclic aziridine) have been...     

Super-Streaming: A New Object Delivery Paradigm for Continuous Media Servers

A number of studies have focused on the design of continuous media, CM, (e.g., video and audio) servers to support the real-time delivery of CM objects. These systems have been deployed in local environments such as hotels, hospitals and cruise ships to support media-on-demand applications. They typically stream CM objects to the clients with the objective of minimizing the buffer space required at the client site. This objective can now be relaxed due to the availability of inexpensive storage devices at the client side. Therefore, we propose a Super-streaming paradigm that can utilize the client side resources in order to improve the utilization of the CM server. To support super-streaming, we propose a technique to enable the CM servers to deliver CM objects at a rate higher than their display bandwidth requirement. We also propose alternative admission control policies to downgrade super-streams in favor of regular streams when the resources are scarce. We demonstrate the superiority of our paradigm over streaming with both analytical and simulation models.Moreover, new distributed applications such as distant-learning, digital libraries, and home entertainment require the delivery of CM objects to geographically disbursed clients. For quality purposes, recently many studies proposed dedicated distributed architectures to support these types of applications. We extend our super-streaming paradigm to be applicable in such distributed architectures. We propose a sophisticated resource management policy to support super-streaming in the presence of multiple servers, network links and clients. Due to the complexity involved in modeling these architectures, we only evaluate the performance of super-streaming by a simulation study.     

Selection of the optimum decomposition level using the discrete wavelet transform for automobile suspension system

Journal of Mechanical Science and Technology - This paper discusses the determination of the optimum decomposition level by using the discrete wavelet transform (DWT) method for an automobile...     

Stability preservation analysis in direct discretization of fractional order transfer functions

In this paper, a class of the direct methods for discretization of fractional order transfer functions is studied in the sense of stability preservation. The stability boundary curve is exactly determined for these discretization methods. Having this boundary helps us to recognize whether the original system and its discretized model are the same in the sense of stability. Finally, some illustrative examples are presented to evaluate achievements of the paper.     

Compact eight-channel wavelength demultiplexer using modified photonic crystal ring resonators for CWDM applications

An eight-channel wavelength demultiplexer by cascading of ring resonators (RRs) in photonic crystal (PhC) structure is proposed in this paper. In designing of this demultiplexer, we used eight square-shaped PhC RRs with different refractive index (RI) of defect rods to generate a distinctive resonance wavelength. Each PhC RR has a specific resonance wavelength with tuning a variety of design parameters such as RI of a whole, defect and inner rods and radius of defect rods. In operating wavelength of λ₀?=?1497 nm, the transmission power and quality factor (Q) of single RR are discovered as 96% and 1000, respectively. The average power transmission, channel spacing, crosstalk and full width at half maximum are found by finite difference time domain method to be about 96?±?1%, 2.25 nm, ??35 dB and 1.5 nm, respectively. Simulation outcomes demonstrate that the designed demultiplexer has a proper operation. The footprint of the designed device is about?~?115 μm², which makes this device a promising for future photonic integrated circuits.