The Internet as an enabler for dynamic pricing of goods

The Internet offers the potential for dynamic pricing for a wide range of products across the supply chain. Dynamic pricing can be formally defined as the buying and selling of goods in markets where prices move quickly in response to supply and demand fluctuations. Unlike physical markets where change occurs slowly because of information delays, change occurs very rapidly on the Internet. In the marketplace, the Internet is a powerful tool for almost instantaneous consumer feedback. For example, prices can be changed dynamically to meet demand because the cost of changing a price may be lower on the Internet than in physical markets. The success of dynamic pricing is helping in the growth of new businesses, including broad-based e-commerce portals new interactive networks. This paper has several objectives. The first objective is to look at factors that affected the use of dynamic pricing in the past. The second objective is to summarize the notion of dynamic pricing over the Internet. The third objective is to examine the different methods for collecting dynamic demand data over the Internet. The final objective is to present two models to optimize the revenue obtained for build-to-forecast and build-to-order environments.     

Manufacturing systems simulated

Manufacturing system simulations performed at the IBM Electronic Card Assembly and Test (ECAT) facility are examined to show how this approach works to improve cycle time and customer service. Simulation was used to determine what could be done in the short run to improve the throughput of a line for manufacturing high-volume token ring adaptor cards used in PCs and workstations. Sophisticated simulation models that focused on the inventory and service level performance of the ECAT plant rather than its production performance were also developed. The benefits gained from these simulations are described     

Elevated IL-10 mRNA expression and downregulation of Th1-type cytokines in microfilaraemic individuals with Wuchereria bancrofti infection

In the present study, we removed the whole area marginalis, Rauber's sickle and the peripheral part of the area centralis from unincubated chicken blastoderms (st IV, Vakaet, 1962a). By placing a fragment of a quail Rauber's sickle (functioning as early gastrulation organizer: Callebaut and Van Nueten, 1994) at different places and oriented in different directions on the remaining central part of the area centralis, we observed, after in vitro culture, a normal embryonic development. This indicates that the area marginalis itself is not indispensable for gastrulation and neurulation. Our study also indicates that none of the three elementary tissues (Rauber's sickle, endophyll and upper layer) of the avian unincubated blastoderm present an irreversible functional polarity.     

Bamboo fabric reinforced polypropylene and poly(lactic acid) for packaging applications: Impact,thermal, and physical properties

The main objective of this study is to explore the potential of using totally green composites made from renewable resources in packaging applications as compared to conventional thermoplastics. In this work, we undertook a comparative study of the functional properties related to the packaging applications of bamboo fabric–Polypropylene (PP) and bamboo fabric–Poly(lactic acid) (PLA) composites. Results indicate that Charpy impact strength was increased from 37.5 to 126 J/m for bamboo fabric–PLA composites and 204 to 278 J/m for bamboo fabric–PP composites compared to the pure polymers. Drop weight impact tests were also performed and the same trend was observed. Results of thermogravimetric analysis, differential scanning calorimetry, and heat deflection temperature analysis have shown that the addition of bamboo fabric improved the thermal resistance of these composites. Results indicate that bamboo fabric is a potential reinforcement for PLA composites, but possible packaging applications should avoid high humidity environment. POLYM. COMPOS., 35:1888–1899, 2014. © 2014 Society of Plastics Engineers     

Influences of process parameters on tensile strength of friction stir welded cast A319 aluminium alloy joints

Fusion welding of cast A319 (Al-Si-Cu) alloy will lead to many problems including porosity, micro-fissuring, and hot cracking. Friction Stir Welding (FSW) can be used to weld A319 alloy without these defects. In this investigation, an attempt has been made to study the effect of FSW process parameters on the tensile strength of A319 alloy welded joints. Joints were made using different combinations of tool rotation speed, welding speed, and axial force, each at four levels. The quality of weld zone was analyzed using macrostructure and microstructure analysis. Tensile strength of the joints were evaluated and correlated with the weld zone microstructure. The joint fabricated with a 1200 rpm tool rotation speed, 40 mm/min welding speed, and 4 kN axial force showed superior tensile strength compared with the other joints.     

Mixing in reactive extrusion of low-density polyethylene melts: Linear vs. branched

The melt flows of linear low-density polyethylene (LLDPE) and branched low-density polyethylene (LDPE) have been compared in a fully intermeshing co-rotating twin-screw extruder. The polyethylene melts were selected in order to investigate the effects of the melt rheology on the mixing. Their shear vicosity curves are quite similar, but the LDPE has a markedly higher apparent extensional viscosity over a wide range of stretch rates. The stagger of the paddles in the mixing zone of the extruder creates axial pressure-driven axial flow can have significant extensional strain components. Residence time distributions obtained in the melt zones of the extruder with tracer dye reveal that the LDPE has a narrower residence time distribution than the LLDPE over a wide range of operating conditions. The axial dispersion for the LDPE is significantly lower than the axial dispersion for the LLDPE. This is attributed to the greater extensional viscosity of the LDPE. During the reactive extrusion process, solid maleic anhydride and polyethylene were added at the feed port but the peroxide provides better control of the crosslinking reaction. Residence time distributions measured for the chemically more reactive LLDPE melt indicate reduced levels of axial mixing with reaction. The reduction in mixing is due to a crosslinking reaction that occurs in parallel to the grafting reaction. This change in mixing is smaller than the difference in mixing between LDPE and LLDPE.     

Junction reinforced pressurized spherical shell with a conical nozzle

In this paper, an analytical solution to the problem of a junction reinforced spherical shell with a conical nozzle under internal pressure is presented. The stresses are determined using Reissner's shallow spherical shell equations together with the solutions corresponding to the conical nozzle in terms of Bessel functions. The reinforcement and the conical nozzle are considered as an elastic discontinuity in the spherical shell causing perturbations in the undisturbed membrane state of stress in the spherical shell. After checking many limiting cases for which analytical or other solutions are available, the computer software developed is applied to a wide range of discontinuity parameters to assess their influence on the stress concentrations. Outside reinforcement is found to be more beneficial compared to inside reinforcement. The method presented is applicable to a wide range of discontinuity dimensions including those for which Esslinger's or Geckler's approximation is not applicable.