A digraph approach to TQM evaluation of an industry

Different total quality management (TQM) environments may be suggested to an organization for improving the quality of products, customer satisfaction, competitiveness and profitability by TQM experts. This paper identifies factors responsible for the TQM environment. All these factors are interacting with each other by different amounts. An attempt has been made to develop a mathematical model of the TQM environment from these interacting factors using a graph theoretic approach. In the graph theoretic model, a directed graph or digraph is used to represent abstract information of the system using directed edges, which is useful for visual analysis. The matrix model developed from the digraph is useful for computer processing. A permanent value of multinomial developed from the matrix represents the environment uniquely by a single number/index, which is useful for comparison, ranking and optimum selection. The method is quite flexible to accommodate new factors and market dynamics in global business in a bid to go for continuous improvement and breakthrough improvement in the environment, product, process and intellectual property rights (IPR).     

Percolation dominated electron transport in Tetracyanoquinodimethane mixed 4,7-diphenyl-1,10-phenanthroline thin films

Highly conducting and electron transporting organic semiconductor tetracyano-quinodimethane (TCNQ) has been added to the well known electron transporting material 4,7-diphenyl-1,10-phenanthroline (BPhen) in various mixing percentages. Electron only devices exhibited a distinctive transition from low to high conductivity. The results have been found to be in good agreement with classical percolation theory with a percolation threshold of 3.8 wt.% and a critical exponent value of 1.3. This demonstrates the formation of a morphologically stable 2D percolating network that has been supported by AFM analysis. The composition thus formed indicates a promising electron injecting material for optoelectronic devices.     

Selective interfacial localization in conducting polycaprolactam/ethylene vinyl acetate/carbon black composites

Unusual electrical conductivity was demonstrated by ethylene vinyl acetate/polycaprolactam/carbon black (CB) composites. The critical exponent value was 1.2 ± 0.2 for ternary composites and was greater than 2.0 for the binary composites, indicating two‐dimensional electrical conduction in ternary composites. The ternary composites also showed inverted U‐shaped conductivity curves when CB weight fraction was greater than 10 wt%. However, at 10 wt% CB, a discontinuous conductivity curve showing conductivity only when polycaprolactam content was greater than 50% was observed, suggesting substantial variation in the interfacial characteristics with the change in the blend composition. Small‐angle X‐ray scattering studies pointed out that ternary composites can be viewed as a two‐phase system with sharp boundaries, and that interface layer in the composites does not exist. Differential scanning calorimetry studies suggested composition dependent variation in the crystallinity of polycaprolactam phase, partially contributing to the increase in the composites' conductivity at higher polycaprolactam fractions. POLYM. COMPOS., 34:912–919, 2013. © 2013 Society of Plastics Engineers     

Molecular Cloning and Sequence Analysis of Bile Salt Hydrolase Gene (bsh) from Lactobacillus plantarum MBUL90 Strain of Human Origin

This study provided genetic information on a bile salt hydrolase (bsh) of a Lactobacillus plantarum strain of Indian origin, MBUL90. L. plantarum strains were screened by PCR for the determination of the bsh locus in their genome using specific primers. None of the lactobacilli strains produced the expected size of amplicon (～ 1.0 kb) except L. plantarum strains, which proved the specificity of the primers. The bsh amplicon of L. plantarum MBUL90 was cloned into pDrive vector, and nucleotide sequences were determined. Sequence analysis of bsh genes revealed a high level of similarity within the species of L. plantarum as well as with other species of Lactobacillus. The resulting nucleotide sequence of an ORF of 975 bp encoded a predicted protein of 324 amino acids representing a theoretical molecular mass of 37 kDa with a pI of 4.92. The protein deduced from the complete ORF had high similarity with other Bsh proteins, and four highly conserved amino acid motifs (YFGRNXD, NEXGLXXAGLNF, VXVLTNNPXF, and SXSRFVRXAF) were located around the active site. Genetic data presented in this paper provide a sound foundation for better understanding the genetic diversity of bsh in Lactobacillus genus and may provide a new genetic marker for phylogenetic study.     

IP layer restoration and network planning based on virtual protection cycles

We describe a novel restoration strategy called virtual protection cycles (p-cycles, patents pending) for extremely fast restoration in IP networks. Originally conceived for use in WDM and Sonet transport networks, we outline the adaption of the p-cycle concept to an IP environment. In an IP router-based network, p-cycles are implemented with virtual circuits techniques (such as an MPLS label switched path, or other means) to form closed logical loops that protect a number of IP links, or a node. In the event of failure, packets which would normally have been lost are encapsulated with a p-cycle IP address and reenter the routing table, which diverts them onto a protection cycle. They travel by normal forwarding or label switching along the p-cycle until they reach a node where the continuing route cost to the original destination is lower than that at the p-cycle entry node. Diverted packets are deencapsulated (dropped from the p-cycle) at that node and follow a normal (existing) route from there to their destination. Conventional routing protocols such as OSPF remain in place and operate as they do today, to develop a longer term global update to routing tables. Diversionary flows on the p-cycle inherently cease when the global routing update takes effect in response to the failed link or node. The p-cycle thus provides an immediate real-time detour, preventing packet loss, until conventional global routing reconvergence occurs. The aim of the paper is to explain the basic p-cycle concept and its adaptation to both link and node restoration in the IP transport layer, and to outline certain initial results on the problem of optimized design of p-cycle based IP networks.     

Strategies to maximize carried traffic in dual-mode cellularsystems

Dual-mode cellular systems based on the EIA/TIA IS-54 standard offer the eventual prospect of carrying up to six digital calls in the same bandwidth as a single analog call. During the transition from analog to digital service, however, the call-carrying capacity of such systems will be limited by the presence of existing analog users. In this situation, it is reasonable to ask if there are call-handling strategies that could increase the total traffic carried by providing preferential treatment to digital users. We consider four such strategies for maximizing the total traffic carried by a dual-mode cellular system. For two of these strategies, including the baseline “no-control” strategy we develop closed-form solutions for carried traffic and other related service statistics. The closed-form solution for the no-control case is then extended to provide a tight upper bound on carried traffic for any control strategy. We also present a method for finding the optimal control strategy by applying linear programming (LP) techniques. The strategies are compared for various proportions of analog and digital users and offered traffic levels. The findings show that it is actually quite difficult to obtain gains using strategies that exploit the difference in spectral efficiency between analog and digital calls, even with formally optimal strategies. While this is an unexpected finding, we feel the conclusion has been well validated and is now understood and explained in the paper     

Characterization of wavelength-selective fiber-optic devices usinga modified phase-shift method

We present a novel measurement setup that can be used for the complete characterization of fiber Bragg gratings and wavelength selective fiber-optic devices. Our setup is based on the phase-shift method (PSM), which we have modified to include the measurement of polarization-induced effects such as polarization-dependant loss (PDL) and polarization-mode dispersion (PMD). We measure the spectral response of devices used in transmission and in reflection, the wavelength dependency of the group delays due to chromatic and polarization-mode dispersion, and the wavelength dependency of the polarization-dependent loss. Experimental results are presented and sources of error are discussed. Comparisons with the Jones matrix eigenanalysis method for the measurement of PDL and differential group delay due to PMD have been carried out     

Laterally coupled InP-based single-mode microracetrack notch filter

We demonstrate an InP-based microracetrack notch filter with >25-dB extinction and 19-nm free-spectral range at 1550 nm. The curved section of the resonator has a radius of 2.25 /spl mu/m. To our knowledge, this represents the best extinction and the smallest radius of curvature for such a device to date.     

Brazing of hot isostatically pressed-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> to stainless steel (AlSl 304L) by Mo-Mn route using 72Ag-28Cu braze

Joining of stainless steel (AISI 304L) to hot isostatically pressed alumina (HIP-Al₂O₃) using the brazing alloy 72Ag-28Cu was investigated. The microstructural characterization at various stages of joining, including metallization, annealing of overlaid Ni coating, and brazing, was comprehensively evaluated. The interface structure and the growth of phases were analyzed with optical microscope, scanning electron microscope, and electron probe microanalyzer (EPMA). Additionally, the leak tightness of these joints was assessed using a He-leak detector. Experimental results indicated the development of the manganese aluminate spinel (MnAl₂O₄) layer at the metallizing stage, which penetrated into HIP-Al₂O₃. The Ni overlaid coating further resulted in the formation of the Ni(Mo) solid solution layer followed by the Mo-rich phase. During the solid-state reaction and subsequent brazing cycle, the growth of the spinel layer close to HIP-Al₂O₃ was not adversely affected. The microstructure of the brazed joint was complex. It showed a eutectic structure within the brazed zone and a thin layer of Mo-rich, Ni-rich phases close to HIP-Al₂O₃. Increasing the brazing time resulted in the excessive growth of the thin layer that seriously affected the leak tightness of the joint.