Measuring matrix-based cell formation with alternative routings

A good measure is necessary to evaluate the goodness of grouping in cellular manufacturing. For simple group technology (GT) problems, there are some grouping measures available, the most cited ones are grouping efficiency and grouping efficacy. A grouping measure, which considers alternative routings, is not available for the generalised GT problems. In this paper a new measure called alternative routing grouping (ARG) efficiency is proposed and its desirable properties are derived. Not only can this alternative routing grouping efficiency be used in the generalised GT problems, but it can also be used in the simple GT problems. The computation of the alternative routing grouping efficiency is illustrated with examples, and results of empirical tests on a set of known problems are also reported in this paper. The alternative routing grouping efficiency is extended to the simple GT measures. Grouping efficiency suffers from a weak discriminating capability and grouping efficacy has relatively a better discriminating capability. It is proved that the ARG efficiency has better discriminating capability than the existing measures, and this measure can evaluate the effectiveness of grouping in both simple and generalised cell formation problems with alternative process plans.     

Isolation, Structure Elucidation, and Biological Activity of Flavone 6-C-Glycosides from Alliaria petiolata

Preparative reversed-phase HPLC analysis of a methanol extract of the seeds of Alliaria petiolata afforded fourflavone 6-C-glycosides: isoorientin, swertiajaponin, swertisin and isoscoparin-2--D-glucopyranoside. The molecular structures were elucidated by UV, ESIMS and comprehensive 1D (¹H and ¹³ C) and 2D (gradient multiple quantum filtered ¹H-¹H COSY, ¹H-¹³C HSQC and ¹H-¹³C HMBC) NMR analyses. The antibacterial and free radical scavenging activity, and general toxicity of these compounds were assessed. While none of these glycosides showed any significant antibacterial activities at test concentrations, all these compounds showed prominent free radical scavenging activity (IC₅₀ values: 1.25×10^-2 to 7.69×10^-3 mg/mL) in DPPH assay. In the brine shrimp lethality assay very low levels of general toxicity (LD₅₀ >1.00 mg/mL) were displayed.     

Reaction of oxalyl and malonyl chloride with 1,1-dimethyl-2-substituted hydrazides

Recently we reported the reaction of 1,1-dimethyl-4-substituted semicarbazides with phosgene to occur with formation of several new heterocyclic ring systems. Here we report the reaction of several semicarbazides, thiosemicarbazides and related acyl substituted hydrazides with oxalyl chloride and malonyl chloride. These reactions occur with the formation of heterocyclic products which are oxadiazolinones, imidazolidinetriones, 2-thioxoimidazolindine-4,5-diones, and 2-thioxo-1,3-diazine-4,6-diones (2-thioxopyrimidine-4,6-diones).     

Cyclic Scheduling for a Multi-product,Single-facility Production System Operating Under a Just-in-time Delivery Policy

Sarker and Parija have developed a model for obtaining the optimal batch size for a single-product manufacturing system operating under a fixed-quantity, periodic delivery policy. In this work, the model is extended to a multi-product situation and a single-facility scheduling scheme is developed for the system. Two situations are considered—one with fixed setup cost and the other with variable setup cost. It is observed that setup cost variability is beneficial to the system under certain conditions.     

Syntheses of new poly (arylene vinylene) analogues: Poly (4,7-benzofuran vinylene) and poly (4,7-benzothiophene vinylene)

The reaction of bis(4,7-tetrahydrothiopheniomethyl) benzofuran dibromide with aqueous tetramethylammonium hydroxide leads to a water-soluble polyelectrolyte which can be film cast and thermolytically eliminated to give poly(4,7-benzofuran vinylene) (PBFV). Subjection of bis(4,7-tetrahydrothiopheniomethyl) benzothiophene dibromide to the same reaction sequence gives poly(4,7-benzothiophene vinylene) (PBTV). UV-VIS studies show that PBFV has a band gap of 2.76 eV, while PBTV has a band gap of 2.92 eV. These polymers are members of a new class of conjugated poly (arylene vinylene)s, in which heterocyclic pseudoaromatic rings are fused onto a poly(1,4-phenylene vinylene) backbone. © 1994 John Wiley & Sons, Inc.     

Cluster structure of <Superscript>16</Superscript>O

A folding potential describing the -scattering on ¹⁶O over a broad energy range 25.8-146.0 MeV is constructed on the basis of -like cluster and unclustered-nucleon configurations of ¹⁶O. The resulting potential does not need any renormalization to fit the angular distribution of elastic cross-sections. The effects of the repulsive part of - and -nucleon interactions are investigated. The analysis suggests that both the - repulsive potential and the unclustered nucleonic configuration in the target are important to describe the scattering data over a broad range of incident energies. The root-mean-square radius for the ¹⁶O nucleus is deduced.Received: 5 December 2002, Published online: 9 October 2003PACS: 25.55.Ci Elastic and inelastic scattering - 24.10.Ht Optical and diffraction models - 21.60.Gx Cluster models     

A macromonomer approach to the synthesis of poly(1,1‐bis(ethoxycarbonyl)‐2‐vinyl cyclopropane‐graft‐dimethyl siloxane)

Poly(1,1‐bis(ethoxycarbonyl)‐2‐vinyl cyclopropane (ECVP)‐graft‐dimethyl siloxane) copolymers were prepared using a macromonomer approach. Poly(dimethyl siloxane) (PDMS) macromonomers were prepared by living anionic polymerization of cyclosiloxanes followed by sequential chain‐end capping with allyl chloroformate. These macromonomers were then copolymerized with ECVP. MALDI‐ToF mass spectrometry and ¹H NMR spectroscopy were used to show that the macromonomers had approximately 80% of the end groups functionalized with allyl carbonate groups. Gradient polymer elution chromatography showed that high yields of the graft copolymers were obtained, along with only small fractions of the PECVP and PDMS homopolymers. Differential scanning calorimetry showed that the low glass transition temperature (T_g) of the PDMS component could be maintained in the graft copolymers. However, the T_g was a function of polymer composition and the polymers produced had T_gs that ranged from ?50 to ?120 °C. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

A comprehensive study of optimization algorithm for wireless coverage in indoor area

Coverage optimization using minimum number of transmitters is critical to service providers and vendors that need to control the coverage as well as the huge costs involved. In this regards, an existing coverage algorithm for determining the minimum number of transmitting antennas as well as their appropriate locations to provide the optimized wireless coverage for indoor environment is studied in this paper. The algorithm uses ray-tracing to predict the signal distribution from the transmitter to the sampling points (receivers) and genetic algorithm to determine the minimum number of transmitters and their corresponding locations to achieve the optimum wireless coverage. The complexity and performance of the algorithm are also analyzed and it is found that it has exponentially increasing complexity of $2^{n}$ and the change of computation time is greater with small change of the number of receiving points. Moreover, under the multi-transmitter scenario (real case), the accuracy achieved by fading, coverage ability, and signal to noise ratio is in the range of 96–99 %.