Recent Patents on Engineering - Volume 1, Issue 3, 2007

Many organizations purchase connectionless Virtual Private Network (VPN) services from a telecommunications service provider, who deploys a network of routers, interconnected by high bandwidth trunks, which serve thousands of customers. The nodes in a service provider network are Provider Edge routers (PEs), which store forwarding tables which dictate on which outgoing link to send an incoming packet addressed to a particular destination. In practice, router capacity may be limited by memory, bandwidth, or processing capacity for BGP (Border Gateway Protocol) sessions used to advertise addresses. We describe three techniques that help a service provider deploy a large-scale VPN service. The first technique shows how a service provider can deploy sets of routers, called “route reflector planes,” to advertise addresses when the number of addresses in the service provider network grows. The second technique, applicable when the number of BGP sessions is the limiting resource, is a method to enhance the network reliability at no additional cost, by having each customer's forwarding table stored on only a small number of PEs. The third technique is a way to estimate the number of VPNs that can be handled by a PE, when memory is the limiting resource.

The explosion of both academic and industrial interest in inorganic/organic hybrid materials and membranes over the past decade primarily arised from their practical and potential applications in such fields as chemical separation, electrochemical sensing, and fuel cells. In view of their significance to the academia and industry, this review gave a brief summary on the recent patents reporting the preparation and application of hybrid materials and membranes. The focus was on the novel synthetic methodologies and potential applications of hybrid materials and the corresponding hybrid charged membranes. The current and future developments were also discussed.

This article presents a patent review on recent development of dense ceramic membranes for gas separation and catalytic chemical reaction. After a basic introduction of membrane materials including their composition, structure and property, a short discussion on the correlation between material structure and property as well as strategies for new material development and screening is presented. The main part of this patent review provides an intensive discussion on the progress achieved up to early 2007. Both oxygen and hydrogen separation together with some examples related catalytic chemical reactions are summarized. Current problems of dense ceramic membranes and membrane reactors are addressed and future technology challenges are also outlined.

This article reviews dozens of recently published patents, patent applications and journal papers for the recent developments in wire bonding for advanced microelectronics interconnections. The problems or challenges related to popular topics such as low-k devices, ultra-fine-pitch wire bonding, insulated wire bonding, low wire loops and copper wire bonding are briefly explained, and a number of new solutions to the problems and recent findings/developments are summarized.

Bioabsorbable polymeric stent has been considered to be a possible remedy for occluded vessels since the long-term complications of bare metal and drug eluting stent have surfaced the water. To make the bioabsorbable polymeric stent a competitive product, polymeric stents must have equivalent mechanical and pharmaceutical functionality to metal ones. Therefore, the bioabsorbable polymeric stents need to have sufficient radial strength and axial flexibility. Stents need to be easily deployed and resistant to recoil. Stents need to be capable of carrying anti-proliferation drugs without sacrificing the mechanical properties. Seventeen patents covering the topics of the shape memory polymer, the design of self-expandable bioabsorbable and slide-and-lock polymeric stents, the design of coil fiber stents, the method to enhance the mechanical strength of stents and method to load drugs into of stents are reported in this review. Three bioabsorbable stents have been or start to be tested in small scale human clinical trials. The 9-month to 4-year follow up results revealed the feasibility and clinical safety of using bioabsorbable polymeric stents. It is foreseeable that more effort will be involved in the future stent commercialization.

Over the past 20 - 30 years, there has been a tremendous increase in the number of bone replacement procedures annually, and there now have an estimated total cost of US$140 billion worldwide. The conventional engineering approach of repairing bone fracture is to implant a synthetic metallic prosthesis. However, bone healing often or sometimes fails and this result leads to substantial levels of disability and consequent long-term worldwide healthcare costs. Therefore, recently, attention has been focused on applying a bioactive coating on the surface of a prosthetic implant to enhance biocompatibility and bioactivity. This article will consider the most relevant developments in this emerging field, addressing three main coating techniques namely plasma spraying, magnetron sputtering and biomimetic deposition.

This review deals with electrochemical methods for water, wastewater, wastes and soils treatment. The electrochemical technique combines both physical chemistry and electronic science and has widely proved to be a clean, flexible and powerful tool for the development of new methods for waste and water treatment. Likewise, electrochemical treatment is generally characterized by simple equipment, ease of operation, short retention time and negligible equipments for adding chemicals. Besides, electrolytic cells can be easily automated and coupled with other processes including, biological, chemical and physical processes to enhance the efficiency of the treatment. A particular focus is given to electrocoagulation (EC), electrodeposition (ED), electroflotation (EF), electrokinetic (EK) and electrooxidation (EO) processes. These technologies are effective in improving the treatment quality of industrial wastes, wastewaters and drinking water on integration into a treatment plant or replacement of conventional processes that are found to be less effective to eliminate specific organic and inorganic pollutants. EC can be used for clarifying water or to eliminate organic, inorganic and microbial pollutants from wastewater. The technology delivers in situ coagulant by anodic dissolution of sacrificial electrodes (aluminium or iron) and is finding wider applications with the possible improvements in the reduction of energy consumption and metallic sludge production. ED is a well-established process for toxic metal removal whose effectiveness can be greatly improved by selecting suitable electrode material (type and geometry of the electrode). EF technology is effective in removing suspended solids, colloidal particles and oil & grease suspension. EK technology is a promising method to remove toxic metals from the matter with low hydraulic permeability or to enhance dewaterability of wastes including soils and sludge. The development of new, more stable and active catalytic electrodes has led to a renewed interest in EO for degrading refractory organic pollutants. This paper covers both established and recent developments in the field of electrochemical technologies for waste, water and wastewater treatment based on more than 158 patents and publications cited or analyzed.

The study of the properties of the materials used in the several fields of the mechanical industry requires an analysis of their mechanical characteristics and behaviour under load, or under a combination of loads, which produce multiaxial stress states on the machine components. The analysis of the behaviour under axial and torsional combined loads, either static or time-variable, proves particularly interesting. During combined loads tests, the test machine should not transmit any parasitic action to the specimen, such as shear and bending moment, in order to consider only the reaction to torsion and axial load. Furthermore, it should allow to apply the torsional and axial actions separately (the application of axial loads must not be influenced by the applied torque and vice-versa). The test machine must also be designed to apply a high torsional moment without producing any non-allowable deformation. This paper reports the results of a survey of universal multiaxial test machines frames for performing torsion, static or fatigue tests on cylindrical specimens, with the simultaneous application of axial, tensile or compression loads, either static or time-variable. A preliminary survey showed that traditional test machines are equipped with a plane frame that cannot withstand a high torsion. A new machine was therefore developed based on a study to provide the most suitable frame structure to withstand a high torsion. The machine was patented.

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