Two views on security software liability. Let the legal system decide

Rather than use the product liability screwdriver as a chisel, why not consider a package of more effective tools. Corporations and individuals that market software despite knowledge of software security flaws should face criminal prosecution as well as civil lawsuits with punitive damages. Perhaps bounties should be available for the first to discover and establish the existence of a security flaw. Publishers should be required to post to the Web and otherwise publicize promptly patch availability. The software equivalent of an Underwriters Laboratories should establish and constantly improve security-related standards and testing protocols. It should be made readily apparent whether a program has passed and at what level. Prospective customers should be educated and encouraged to insist on software that has passed. Stronger software security is important. Software developers and publishers must do better. But product liability is not the right legal tool for the job.     

Improved practical support for large-scale requirements prioritising

An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments. This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed. A support tool for the improved process has been developed to make the process more practical in commercial developments. The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is an important step in that direction.     

Control topology options for single-phase UPS inverters

Four control topologies for single-phase uninterruptible power system (UPS) inverters are presented and compared, with the common objective of providing a dynamically stiff, low total harmonic distortion (THD), sinusoidal output voltage. Full-state feedback, full-state command controllers are shown, utilizing both filter inductor current and filter capacitor current feedback to augment output voltage control. All controllers presented include output voltage decoupling in a manner analogous to “back EMF” decoupling in DC motor drives. Disturbance input decoupling of the load current and its derivative is presented. An observer-based controller is additionally considered and is shown to be a technically viable, economically attractive option. The accuracy transfer function of the observer estimate is used to evaluate its measurement performance. Comparative disturbance rejection is evaluated by overlaying the dynamic stiffness (inverse of output impedance) frequency response of each controller on a single plot. Experimental results for one controller are presented     

A review of modeling approaches for oriented semi-crystalline polymers

Modeling changes in the physical properties of oriented semi-crystalline polymer films is beneficial for understanding the fundamentals associated with structure property relationships and could be used for developing new polymer films with significantly enhanced physical properties. Relating the molecular changes observed in oriented polymer films to inherent polymer characteristics provides valuable insight for the development of new polymers which exhibit enhanced physical properties upon orientation. Modeling efforts will be reviewed that have attempted to use fiber composite theory to explain the transitions seen during the orientation process.     

A comparative evaluation of dental luting cements by fracture toughness tests and fractography

In recent years there has been a shift from traditional methods of investigating dental materials to a fracture mechanics approach. Fracture toughness (KIC) is an intrinsic material property which can be considered to be a measure of a material's resistance to crack propagation. Glass-ionomer cements are biocompatible and bioactive dental restorative materials, but they suffer from poor fracture toughness and are extremely susceptible to dehydration. The main objective of this study was to evaluate the fracture toughness of three types of commercially available dental cements (polyacid-modified composite resin, resin-modified and conventional glass ionomer) using a short-rod chevron-notch test and to investigate and interpret the results by means of fractography using scanning electron microscopy. Ten specimens of each cement were fabricated according to manufacturers' instructions, coated in varnish, and stored at ambient laboratory humidity, 100 per cent relative humidity, or in water at 37 degrees C for 7 days prior to preparation for testing. Results indicated that significant differences existed between each group of materials and that the fracture toughness ranged from 0.27 to 0.72 MN/m3/2. It was concluded that the resin-modified glass-ionomer cement demonstrated the highest resistance to crack propagation. Fractographs clearly showed areas of stable and unstable crack growth along the fractured surfaces for the three materials examined.     

Magnetic multipole line-cusp plasma generator for neutral beam injectors

The magnetic multipole line-cusp device developed by MacKenzie and associates has been adapted for use as a neutral beam ion source. It has produced high-density, large volume, quiescent, uniform hydrogen plasmas, which makes it a potential candidate for use as a plasma generator for neutral beam injectors. The device is a water-cooled cylindrical copper discharge chamber (25 cm in diameter by 36 cm long) with one end enclosed by a set of extraction grids with a 15-cm-diam multi-aperture pattern. The chamber wall serves as an anode and is surrounded by an external system of rare-earth cobalt magnets arranged in a line-cusp geometry of 12 cusps; plasma is produced by electron emission from a hot cathode assembly. This source has achieved extracted beam currents of 12 A at 18.5 kV, radial plasma density uniformities of +/-5% over a 15-cm diameter, noise levels of less than +/-0.5%, and arc efficiencies (beam current/arc power) of 0.6 A/kW.     

The Diffusible Signal Factor Family of Bacterial Cell?Cell Signals

Bacterial cell-to-cell signals of the diffusible signal factor (DSF) family are cis-2-unsaturated fatty acids that differ in their chain length and branching patterns. Signaling involving DSF family members occurs in diverse bacteria to include plant and human pathogens. In the majority of these organisms, the perception of DSF is linked to turnover of the second messenger cyclic di-GMP by one of two “core” pathways. Additional “accessory” signal transduction pathways can also be found, but are not widely conserved. DSF signaling acts to regulate diverse functions to include biofilm formation and architecture, antibiotic resistance, and the production of virulence factors in pathogens. DSF family signals can also participate in interspecies signaling with other bacteria and interkingdom signaling with the yeast Candida albicans. Such interactions may have importance in modifying microbial behavior during polymicrobial infections.     

LOSING CLARITY Data,Information, and Knowledge Administration

Abstract

Learning to live with, and then take advantage of, changing roles and responsibilities may be one of the greatest challenges a mature information systems specialist faces today.     

Examining spatial patterns in affordable housing: the case of California density bonus implementation

California State Density Bonus Law §65915–18 financially incentivizes housing developers to produce affordable housing by granting density bonuses to those who designate a percentage of the total units for residence by low or moderate income households. By incorporating affordable housing units alongside market-rate units, state density bonus law fosters opportunities to enhance neighborhood level socio-economic diversity. This paper investigates the effectiveness of density bonus policy at promoting socio-economic diversity within the City of San Diego by examining locational patterns of density bonus implementation and neighborhood demographic characteristics. This study utilizes spatial and non-spatial statistical analyses to identify trends and correlations in density bonus usage, housing stock, and racial and economic characteristics. The results indicate that density bonus usage in San Diego has not fostered socio-economic integration; rather its usage is clustered in neighborhoods characterized by high concentrations of Hispanics, Blacks, and multi-family housing units. The findings underscore the need to refine supply-side affordable housing tools so that they are effective in a range of land markets, and not only in the traditionally lower value land markets where minority households tend to reside.     

A nitric oxide sensor fabricated through e-jet printing towards use in bioelectronics interfaces

Journal of Applied Electrochemistry - We have developed a methodology for electrohydrodynamic printing of a nitric oxide (NO) sensor. The primary features of this amperometric methodology include...