Web-based product and process data modelling in concurrent “design for X”

This paper is concerned with employing the web technology for concurrent modelling of product and process data on the Internet. This is one of the essential tasks of an attempt to develop a generic web-based Design for X (DFX) shell which can be tailored or extended to develop and apply a variety of DFX tools easily, quickly and consistently. The emphasis is placed on the use of a number of formal but pragmatic constructs. Bills of materials are used to describe and analyse the overall product structure and characteristics. Flow process charts are used to describe and analyse the overall process structure and characteristics. Standard operation process charts are modified to describe and analyse the interactions between the overall product and process structures. These concepts have already been widely used by practitioners or at least are familiar to various personnel involved in product development. They are coded as reusable ActiveX components that can be easily deployed in the DFX shell.     

High speed and low loss, bulk electroabsorption waveguide modulators at 1.3 mu m

Bulk InGaAsP electroabsorption waveguide modulators based on a novel multiquaternary layer design which have a tapered-fiber-modulator-tapered-fiber insertion loss as low as 4.5 dB and a small-signal frequency response in excess of 11 GHz at lambda =1.33 mu m are described. This design allows one to decouple somewhat the electrical and optical properties of the device. By choosing the appropriate quaternary composition of the core and the cladding layers, the coupling to a tapered fiber can be optimized, while the position and thickness of the p-i-n junction can be varied independently to meet operating voltage and speed requirements without affecting the waveguide mode. A -3 dB small-signal modulation bandwidth in excess of 11 GHz was measured.<>     

The influence of linoleic acid intake on the kinetics of adenine nucleotide translocase

Dietary enrichment of mitochondrial polyenoic fatty acid content was associated with increased respiratory activity (Abuirmeileh and Elson). The influence of the membrane lipid composition on the adenine nucleotide translocase (AdNT) was studied in rats that were fed diets formulated with beef tallow (BT) to provide low or safflower oil (SO) to provide high contents of linoleic acid. The phosphatidylcholine/phosphatidylethanolamine ratio was 40% higher in the SO mitochondria due primarily to an increase in phosphatidylcholine. SO mitochondria exhibited 25% higher state 3 respiration, 50% higher state 4 respiration and 13% higher net ADP-dependent respiration than did the BT mitochondria. The relative RCR and ADP/O values of the SO mitochondria were slightly but significantly (p<0.01) lower. The kinetics of the AdNT were determined by the back exchange method (Pfaff and Klingenberg). At all assay temperatures, SO mitochondria exhibited a higher K_m for ADP. However, addition of 5 mM carnitine to the assay mixture increased the affinity of the SO-AdNT giving K_m values similar to that of the BT-AdNT. Washing the mitochondria with fat-free BSA had a similar, but lesser, effect. At 25 C and 37 C, the V_max of the SO-AdNT were increased by 11–15% (p<0.05) which was independent of either BSA-wash or the presence of carnitine. According to Dixon plot studies, the SO-AdNT had a comparable K_i for atractylate but a slightly lower K_i for palmitoyl-CoA inhibition. The accumulation of acyl-CoA esters in the SO mitochondria was not ruled out. The overall results suggest that changes in mitochondrial membrane lipids accommodated an increased V_max of the SO-AdNT, which in turn accounted for that part of the increased state 3 respiration dependent on ADP translocation.     

Molecular beam epitaxy-grown PbSnTe-PbEuSeTe buried heterostructurediode lasers

Buried heterostructure (BH) PbSnTe-PbEuSeTe lasers with a PbSnTe active layer were fabricated for the first time using a two-stage molecular beam epitaxy (MBE) growth procedure. Lasers with 4-μm-wide and 0.65-μm-thick buried Pb_0.961Sn_Sn0.039Te active layer and Pb_0.985Eu_0.015Se_0.02Te _0.98 cladding layers were grown. Continuous wave (CW) operating temperature of 175 K was measured with CW threshold currents of 1.6 mA (20 K), 13.6 mA (80 K), and 195 mA (160 K). Single-mode operation with 3.0-cm^-1-mode tuning was measured at 1639.8 cm ^-1 emission     

Brokering the customer-supplier partnership in product design and realization over the World Wide Web

This research is concerned with the application of the World Wide Web (WWW or web) technology to facilitate the early supplier involvement in new product development. The paper focuses on two parts of the resulting web-based system. The first part is the Bid Explorer underpinned by a bid model which is based on design specification. The bid model consists of inquiries which in turn have values of different types. Inquiries are represented in a hierarchical tree. The bid model is collaboratively established by, and thereafter commonly shared between, the customer and all the interested suppliers. From the point of view of the customer, the inquiries are their requirements. In contrast, from the supplier's viewpoint the inquiries are their capabilities. The second part of the system is the Partnership Explorer which is underpinned by a partnership model. This partnership model uses four types of numeric partnership indices, namely satisfaction index (SI), flexibility index (FI), risk index (RI), and confidence index (CI). The SI is based on the overlap between the customer requirements and supplier capabilities. The FI is based on the surplus of the supplier capabilities in relation to the customer requirements. The RI is evaluated through the shortage of the supplier capabilities with reference to the customer requirements. The CI is based on the past performance records of a supplier.     

A novel mitochondrial DNA point mutation associated with mitochondrial encephalocardiomyopathy

A novel mitochondrial DNA (mtDNA) mutation at position nt 4320 in the tRNA(Ile) gene was associated with severe encephalopathy in a 7-month-old infant, who died of intractable hypertrophic cardiomyopathy. The mutation was present in heteroplasmic fashion (88%) in muscle and fulfills accepted criteria for pathogenicity. This is the fourth pathogenic mutation identified in this gene, which appears to be a "hotspot" for deleterious mutations affecting the heart. This report adds to the evidence of genetic heterogeneity in hypertrophic cardiomyopathies.     

Immunohistological evidences of Ginkgo biloba extract altering Bax to Bcl-2 expression ratio in the hippocampus and motor cortex of senescence accelerated mice

Ginkgo biloba extract 761 appears to display neuroprotective effect in many nervous diseases and aging. Deterioration of mental functions during aging is always accompanied by loss of neurons, presumably through apoptosis. Here, we studied the effect of G. biloba extract in the expression of Bax/Bcl-2 ratio, an important apoptotic index, in the hippocampus and motor cortex of the aging brain. Bax and Bcl-2 expressions were examined with immunohistochemical methods. Senescence Accelerated Mice Prone Strain 8 was used because the aging process was accelerated with neuropathological alterations similar to those found in the aging human brain. The mice were fed with either G. biloba extract or sucrose from the age of 3 weeks until sacrifice at 3 or 9 months old. In the hippocampus of G. biloba fed 9-month-old mice, the ratio of Bax positive cell to Bcl-2 positive cell (Bax/Bcl-2 expression ratio) was 11.43 +/- 3.11 (mean +/- SD); significantly lower (P < 0.05) than the Bax/Bcl-2 expression ratio of 20.99 +/- 5.34 in the sucrose fed mice. The Bax/Bcl-2 expression cell ratios, however, in the motor cortex were not significantly different between the two groups (2.22 +/- 1.35 versus 2.27 +/- 2.02 for the G. biloba and the sucrose fed mice, respectively). The decrease in the Bax/Bcl-2 expression cell ratio following G. biloba treatment might hence be able to protect the aging hippocampus from moving further down the apoptotic pathway. Western blotting confirmed the decrease of Bax in the brain even after a short term and high dose Ginkgo treatment. It is speculated that the G. biloba extract may be a potential neuroprotective agent against apoptosis through the differential expressions of the Bax and Bcl-2 in the hippocampus.     

Estimation of elliptical basis function parameters by the EMalgorithm with application to speaker verification

This paper proposes to incorporate full covariance matrices into the radial basis function (RBF) networks and to use the expectation-maximization (EM) algorithm to estimate the basis function parameters. The resulting networks, referred to as elliptical basis function (EBF) networks, are evaluated through a series of text-independent speaker verification experiments involving 258 speakers from a phonetically balanced, continuous speech corpus (TIMIT). We propose a verification procedure using RBF and EBF networks as speaker models and show that the networks are readily applicable to verifying speakers using LP-derived cepstral coefficients as features. Experimental results show that small EBF networks with basis function parameters estimated by the EM algorithm outperform the large RBF networks trained in the conventional approach. The results also show that the equal error rate achieved by the EBF networks is about two-third of that achieved by the vector quantization-based speaker models.