An automated coding and classification system with supporting database for effective design of manufacturing systems

The philosophy of group technology (GT) is an important concept in the design of flexible manufacturing systems and manufacturing cells. Group technology is a manufacturing philosophy that identifies similar parts and groups them into families. Beside assigning unique codes to these parts, group technology developers intend to take advantage of part similarities during design and manufacturing processes. GT is not the answer to all manufacturing problems, but it is a good management technique with which to standardize efforts and eliminate duplication. Group technology classifies parts by assigning them to different families based on their similarities in: (1) design attributes (physical shape and size), and/or (2) manufacturing attributes (processing sequence). The manufacturing industry today is process focused; departments and sub units are no longer independent but are interdependent. If the product development process is to be optimized, engineering and manufacturing cannot remain independent any more: they must be coordinated. Each sub-system is a critical component within an integrated manufacturing framework. The coding and classification system is the basis of CAPP and the functioning and reliability of CAPP depends on the robustness of the coding system. The proposed coding system is considered superior to the previously proposed coding systems, in that it has the capability to migrate into multiple manufacturing environments. This article presents the design of a coding and classification system and the supporting database for manufacturing processes based on both design and manufacturing attributes of parts. An interface with the spreadsheet will calculate the machine operation costs for various processes. This menu-driven interactive package is implemented using dBASE-IV. Part Family formation is achieved using a KAMCELL package developed in TURBO Pascal.     

Iodine-loaded poly(silicic acid) gellan nanocomposite mucoadhesive film for antibacterial application

Iodine-loaded poly(silicic acid) gellan nanocomposite film was fabricated and evaluated for antibacterial properties. Poly(silicic acid) nanoparticles were synthesized by condensation of silicic acid under alkaline conditions in the presence of polyvinyl pyrrolidone, phosphate ions, and molecular iodine. The nanoparticles were incorporated into gellan dispersion to prepare gellan nanocomposite film using the solvent casting method. The nanocomposite films were characterized by Fourier transformed infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction studies. The results of characterization studies indicated improved thermal stability and an increase in the degree of crystallinity. The scanning electron micrographs and energy dispersive X-ray spectrum confirmed the uniform dispersion of silica and iodine in the nanocomposite films. The analysis of physical and mechanical properties revealed the enhanced tensile strength, moisture resistance, and higher folding endurance of poly(silicic acid) gellan nanocomposite films as compared to gellan film. Further, the iodine-loaded poly(silicic acid) gellan nanocomposite films showed good antibacterial activity against Staphylococcus aureus and Escherichia coli and effective mucoadhesive strength. The results indicate that iodine-loaded poly(silicic acid) gellan nanocomposite mucoadhesive film can be used for potential antibacterial applications in pharmaceuticals.     

Cuckoo Search Based Optimization of Multiuser Cognitive Radio System Under the Effect of Shadowing

Shadow fading is one of the least investigated factors of received signal power in a typical wireless communication system. Variations in the received power caused by shadowing events can impose some serious changes in the communication. This paper, proposes a new multiuser cognitive radio system in shadowing environment and its design optimization using cuckoo search algorithm. The transmission parameters of multiple secondary users in the purposed CR model are considered on the basis of IEEE 802.22 WRAN standard. An attempt to optimize these parameters in shadowing environment to achieve multiple objectives for desired quality of service have been made using a relatively newer and simpler cuckoo search algorithm. The optimization results have been compared with another efficient biogeography based optimization technique and the traditional simulated annealing.     

Whale Optimization Algorithm Approach for Performance Optimization of Novel Xmas Tree-Shaped FinFET

Silicon - Today, Fin shaped Field Effect Transistors (FinFETs) are the framework of the sub-nanometer technology node. The leading semiconductor industry deploys it in low-power (LP) and...     

Subthreshold Current Modeling of Stacked Dielectric Triple Material Cylindrical Gate All Around (SD-TM-CGAA) Junctionless MOSFET for Low Power Applications

Silicon - Stacked Dielectric Triple Material Cylindrical Gate All Around (SD-TM-CGAA) Junctionless MOSFET has been explored for low power applications. This paper presents an analytical model of...     

Estimation of greenhouse gas emissions from municipal wastewater treatment systems in India

Greenhouse gas (GHG) emissions generated from municipal wastewater treatment plants in India is estimated in this study. The emissions from the wastewater treatment process as well as from the electricity used during the treatment process are estimated by using the methodology of Intergovernmental Panel on Climate Change. The present treatment plants of capacity 15 997 million litres per day (MLD) contributes towards GHG emissions of 7.3 Mt of CO₂‐eq/year. The future GHG emissions would depend upon the treatment technology used for treating 34 109 MLD of untreated wastewater. The highest GHG emissions would occur if all new wastewater treatment plants are based on upflow anaerobic sludge blanket technology, 19.66 Mt CO₂‐eq/year and lowest if sequential batch reactor technology is adopted, 2.93 MtCO₂‐eq/year.     

Combined Effect of Turbulence,Load Orientation and Rotor Flexibility on the Performance of Three-Lobe Bearings

A three-lobe journal bearing is analytically investigated to determine its dynamic performance when three main parameters, i.e. turbulence, load orientation, and rotor flexibility are varied. Reynolds numbers up to 12000, rotor dimensionless flexibilities up to 4, and load orientations up to 30 degrees on either side of the vertical load line are considered. Thus, almost all cases of practical interest are studied. The stability of a three-lobe bearing improves due to turbulence at high Sommerfeld numbers (more than 0.6) for a rigid rotor, while it is virtually the same for flexible rotors. Conversely, the load orientation has a pronounced effect on stability for both rigid and flexible rotors.     

Demonstration of cellular aging and senescence in serially passaged long-term cultures of human trabecular osteoblasts

The proliferative capacity and cellular and biochemical characteristics of human trabecular bone osteoblasts were analysed throughout their replicative lifespan in vitro. Like several other cell types, human osteoblasts demonstrated a typical Hayflick phenomenon of cellular aging comprising a period of rapid proliferation until cumulative population doubling level (CPDL) 22 to 24, followed by a phase of slow growth and the final cessation of cell division at CPDL 32 to 34. Comparing young cells (less than 20% lifespan completed) and old cells (more than 90% lifespan completed) revealed a progressive increase in population doubling (PD) time, a decrease in attachment frequency, a decrease in the number of S-phase positive cells, a decrease in the rates of DNA, RNA and protein synthesis, an increase in the protein content per cell and an increased proportion of senescence-specific beta-galactosidase positive cells. While osteoblastic production of collagen type I decreased progressively during aging, alkaline phosphatase activity dropped rapidly after the first few passages and then remained constant during the rest of the proliferative lifespan, Significant morphological changes from thin and spindle-shaped early passage young cells to large, flattened and irregularly shaped late passage old cells full of intracellular debris were observed. In comparison, osteoblasts established from an osteoporotic bone sample showed a maximum CPDL of less than 5, had a longer PD time and exhibited abnormal senescent morphology. Thus, we have demonstrated for the first time that human osteoblasts, like several other diploid cell types, have a limited proliferative capacity in vitro and undergo aging and senescence as measured by various cellular and biochemical markers. In addition, preliminary studies show that cells from osteoporotic bone have a severely reduced proliferative capacity. This model of bone cell aging facilitates study of the molecular mechanisms of osteoblast senescence as well as factors related to osteoblast dysfunction in patients with osteoporosis.     

Synthesis and evaluation of ciprofloxacin-loaded carboxymethyl tamarind kernel polysaccharide nanoparticles

Nanotechnology is currently employed as a tool to fight more efficiently against human pathogens. Nanoparticles can be prepared from a variety of materials such as protein, biodegradable polymers and synthetic polymers. Tamarindus indica Linn. or tamarind is one of the most important biodegradable polymer. In the present study, chemically modified polymer of tamarind ‘carboxymethyl tamarind kernel polysaccharide’ (CMTKP) is used for the synthesis of nanoparticulate formulation. Antibacterial activity of CMTKP was analysed which was then enhanced by incorporating a flouroquinolone antibiotic, ciprofloxacin to it. Ciprofloxacin-loaded CMTKP nanoparticles were synthesised via ionotropic gelation technique. Nanosuspension so formed was lyophilised by addition of a cryoprotectant. Nanoparticles obtained were characterised for its particle size, morphology and stability. Interaction studies were confirmed by Fourier transform infrared spectroscopy (FT-IR). Antibacterial activities of ciprofloxacin, CMTKP and ciprofloxacin-loaded CMTKP nanoparticles were tested against two Gram negative and positive bacteria. The antibacterial assay results revealed greatest zone of inhibition by ciprofloxacin-loaded CMTKP nanoparticles in Micrococcus luteus. Toxicity analysis of the prepared formulation was carried out on vero cell lines via resazurin assay which revealed its minimum toxicity.