The Slow Pace of Rapid Technological Change: Gradualism and Punctuation in Technological Change

Discussions of technological change have offered sharply contrastingperspectives of technological change as gradual or incrementaland the image of technological change as being rapid, even discontinuous.These alternative perspectives are bridged using the punctuatedequilibrium framework of evolutionary biology. Using this framework,it is argued that the critical event is not a transformationof the technology, but speciation—the application of existingtechnology to a new domain of application. As a result of thedistinct selection criteria and the degree of resource abundancein the new domain, a new technological form may emerge. Thenew technological form may be able to penetrate other nichesand, in particular, may precipitate a process of ‘creativedestruction’ and out-compete prior technologies. Thisframework is applied to an historical study of wireless communicationfrom the early experimental efforts of Hertz to the modern developmentof wireless telephony.     

Characteristics of Frozen Desserts Sweetened with Fructose and Lactose

Combinations of fructose and lactose were used as the major sweetening agents in ice cream-type frozen dessert formulations. In addition to the sweeteners, variable amounts of caseinate were subjected to a 2³ factorial experimental design in order to evaluate the most suitable combinations of lactose (4.5% or 5.5%), fructose (7.5% or 8.5%) and sodium caseinate (2% or 3%). Comparative chemical, physical and sensory analyses indicated that a formulation using 5.5% lactose, 8.5% fructose and 2% sodium caseinate gave product acceptability similar to that of an ice cream of standard ingredient array and composition.     

Heats of Solution, Density, and Refractive Index Changes in Sodium Borate Glasses Subjected to High Pressure

The densification produced in sodium borate glasses by pressures to 40 kbars at 25° and 250°C was measured. At a constant temperature and pressure, the densification decreased with increasing alkali content. For specimens pressed at 40 kbars and 250°C, the densification ranged from 14.2% for B₂O₃ to 6.3% for the 33.3 mole % Na₂O composition. Under the same conditions, the refractive index increase ranged from 4.8 to 1.1%, and the decrease of the molar refraction of the oxygen ions ranged from 2.5 to 1.5%. The heats of solution of the pressed glasses were more negative than those of the corresponding unpressed glasses. The heats of solution of both the pressed and unpressed glasses pass through a minimum near 20 mole % Na₂O. A decrease in density was observed at room temperature for all pressed specimens. Electron micrographs were made of two of the pressed specimens. The results could be explained on the basis of a repacking of structural units.     

Sport And Downtown Development Strategy If You Build It,Will Jobs Come?

ABSTRACT: Many policy analysts have cautioned against public spending for professional and amateur sports. Within the last year, numerous cities have received demands from major and minor league teams for investments. These investments by the public sector can involve hundreds of millions of dollars and are usually defended by the economic impact of the facilities or teams and the economic development and revitalization which will follow. Indianapolis formulated an economic development strategy which relied substantially on sports. In addition, its development policies did not involve one team or facility, but a series of investments. As a result, the policies followed in Indianapolis afford an opportunity to measure the ability of sport facilities to encourage other investments and enhance economic development. The results reported here indicate that a sports strategy, even one as pronounced and as articulated as that of Indianapolis, is likely to have an inconsequential impact on development and economic growth.     

The GLRT for statistical process control of autocorrelated processes

This paper presents an on-line Statistical Process Control (SPC) technique, based on a Generalized Likelihood Ratio Test (GLRT), for detecting and estimating mean shifts in autocorrelated processes that follow a normally distributed Autoregressive Integrated Moving Average (ARIMA) model. The GLRT is applied to the uncorrelated residuals of the appropriate time-series model. The performance of the GLRT is compared to two other commonly applied residual-based tests - a Shewhart individuals chart and a CUSUM test. A wide range of ARIMA models are considered, with the conclusion that the best residual-based test to use depends on the particular ARIMA model used to describe the autocorrelation. For many models, the GLRT performance is far superior to either a CUSUM or Shewhart test, while for others the difference is negligible or the CUSUM test performs slightly better. Simple, intuitive guidelines are provided for determining which residual-based test to use. Additional advantages of the GLRT are that it directly provides estimates of the magnitude and time of occurrence of the mean shift, and can be used to distinguish different types of faults, e.g., a sustained mean shift versus a temporary spike.     

Shape control of multi-cellular inflatable panels

Multi-cellular inflatable structures are ultra-light and robust against membrane damage such as pinholes caused by space debris. Due to their robustness, inflatable structures supported by inner gases can be applied as space structures. In the present study, shape control for a simple multi-cellular inflatable panel was achieved via a novel diaphragm mechanism. When the bending actuator in a center membrane bends, the inner pressures of sub-cells become different, and the diaphragm mechanism bends as a whole. Because a sliding component is not included, this deformable system is a reliable mechanism. In addition, the proposed mechanism has higher rigidity than that of a bending actuator used alone. In the present paper, we investigate the feasibility of a novel diaphragm mechanism and its characteristics using experimental and numerical results.     

ASSESSMENT OF SODIUM DICHLOROISOCYANURATE IN THE CONTROL OF MICROBIOLOGICAL CROSS-CONTAMINATION IN BROILER CARCASS IMMERSION CHILLING SYSTEMS

Commercial immersion chilling systems used in poultry processing are a major source in the cross-contamination of carcasses with pathogenic microorganisms. In the current study, the efficacy of a chlorine based bactericidal compound, sodium dichloroisocyanurate (NADCC), to control contamination between carcasses was compared to the more traditional sodium hypochlorite solutions in a simulated carcass immersion chilling system. The addition of either sodium dichloroisocyanurate or sodium hypochlorite to the immersion chill tank water at concentrations of 50 ppm or more significantly reduced total aerobic mesophilic (37C) and psychrophilic (22C) counts when compared to corresponding untreated water samples in which dressed broiler carcasses had been immersed ( P < 0.01). Both compounds significantly reduced the numbers of fecal coliforms and thermophilic campylobacters in the immersion water samples compared to corresponding control samples ( P < 0.01). In contrast to the control water samples, salmonellae were not detected in immersion water samples treated with either of the chlorine based compounds.     

COMPOSITION OF WASHED MECHANICALLY SEPARATED AND HAND BONED BEEF

Washed mechanically separated (MS) beef and washed hand boned (HB) beef samples were prepared with an emulsifier or silent cutter. Higher yields of washed beef were obtained with the silent cutter, but differences in composition were small. Bone particle size in MS beef was reduced with the emulsifier and the silent cutter. Washed MS beef contained more iron, fat and cholesterol than washed HB beef. Collagen content of washed MS beef was about twice as high (P < 0.05) as that of washed HB beef. The major proteins in all washed beef lots were myosin and actin. Minor differences in amino acids and fatty acids between MS beef and HP beef existed. Binding properties of washed beef and fish surimi in restructured beef steaks were similar. Overall, washed MS and HB beef are low in fat and high in protein quality and have the potential to replace much of the salt in restructured beef products.     

The effect of varying the calcium-sequestering salt cation on the hydration behaviour of rennet caseins in a simple model system

Di potassium orthophosphate and di-ammonium orthophosphate were used to replace di-sodium orthophosphate in a simple model of cheese analogue manufacture. Rheological changes that occurred as eight rennet caseins, possessing widely differing hydration behaviour, were dispersed in solutions of the different calcium-sequestering salts were determined. Dispersion in the potassium salt resulted in minor differences in hydration behaviour of rennet caseins when compared to the behaviour in di-sodium orthophosphate solution, while dispersion in the ammonium salt resulted in considerably modified hydration behaviours and rheological profiles.