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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jebo.2004.07.013 Byline: A. Ponzi (a), A. Yasutomi (b), K. Kaneko (a) Keywords: Economic production network; von Neumann's static model; Production process Abstract: A dynamical model of an economic production network is proposed as an extension of von Neumann's static model. Sets of input commodities are jointly converted into sets of output commodities by production processes. The rate of production of a given production process is limited by the minimum quantity of its set of input commodities. It is shown that economic production is autonomously sustained, without price divergence, even without the imposition of any external constraints on price determination. This is accomplished through switching between different choices of the minimum input commodity, which leads to the appearance of complex cyclic behaviour. The mechanism and origin of this oscillation is analysed in depth. The generation of complex oscillations with multiple timescales is also shown when several processes are combined to form a chain or a network. Author Affiliation: (a) Department of Pure and Applied Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo 153, Japan (b) Interfaculty Initiative in Information Studies, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan Article History: Received 26 October 2003; Accepted 21 July 2004

A new technique of superwide pressure range adsorption (SWPA) isotherm measurement of N2 from P/P0=10 super -9 to 1 at 77 K is developed and the SWPA isotherms of N2 on activated carbon fiber, molecular sieve carbon, and carbon black is compared with those of their ordinary pressure range isotherms and the simulated isotherms calculated with grand canonical Monte Carlo technique. The new SWPA method can elucidate the presence of ultramicroporosity as per the conclusion.

The objective of this paper is to report the effects of Reynolds number and hub-to-tip ratio on the performance of the impulse turbine for wave energy conversion. The turbine was investigated experimentally under steady and sinusoidally oscillating flow conditions by model testing. As a result, it was found that the critical value of Reynolds number and the optimum hub-to-tip ratio am approximately 4.0 X [10.sup.4] and O. 7, respectively: Furthermore, their effect on starting characteristics have been clarified.

A Wells turbine for wave power conversion has hysteretic characteristics in a reciprocating flow. The counterclockwise hysteretic loop of the Wells turbine is opposite to the clockwise one of the well-known dynamic stall of an airfoil. In this paper, the mechanism of the hysteretic behavior was elucidated by an unsteady three-dimensional Navier-Stokes numerical simulation. It was found that the hysteretic behavior was associated with a streamwise vortical flow appearing near the blade suction surface. In the accelerating process of axial flow velocity, the vortex is intensified to enlarge the flow separation area on the blade suction surface. In the decelerating flow process, the flow separation area is reduced because of the weakened vortex. Therefore, the aerodynamic performance in the accelerating flow process is lower than in the decelerating flow process, unlike the dynamic stall. Based on the vortex theorem, the mechanism to vary the intensity of the vortex can be explained by the trailing vortices associated with the change in the blade circulation.

Lactococcus lactis has been reported unable to directly incorporate mononucleotides but instead requires their external dephosphorylation by nucleotidases to the corresponding nucleosides prior to their incorporation. Although Lactobacillus gasseri PA-3 (PA-3), a strain of lactic acid bacteria, has been found to incorporate purine mononucleotides such as adenosine 5'-monophosphate (AMP), it remains unclear whether these bacteria directly incorporate these mononucleotides or incorporate them after dephosphorylation to the corresponding nucleosides. This study evaluated whether PA-3 incorporated radioactively-labeled mononucleotides in the presence or absence of the 5'-nucleotidase inhibitor α,β-methylene ADP (APCP). PA-3 took up 14C-AMP in the presence of APCP, as well as incorporating 32P-AMP. Furthermore, radioactivity was detected in the RNA/DNA of bacterial cells cultured in the presence of 32P-AMP. Taken together, these findings indicated that PA-3 incorporated purine mononucleotides directly rather than after their dephosphorylation to purine nucleosides and that PA-3 utilizes these purine mononucleotides in the synthesis of RNA and DNA. Although additional studies are required to identify purine mononucleotide transporters in PA-3, this study is the first to show that some lactic acid bacteria directly incorporate purine mononucleotides and use them for growth. [ABSTRACT FROM AUTHOR]

This work investigated an air turbine with self-pitch-controlled blades operating in the airflow generated by an oscillating water column (OWC) under irregular wave conditions to determine turbine performance and identify the optimum blade pitch angle setting. Rotor models with fixed blades were tested under steady flow conditions. The running and starting characteristics of the turbine under irregular wave conditions were determined from a computer simulation that modeled both the turbine and the air chamber The performance of the air turbine was evaluated and the optimum rotor blade limit was found to be about 10 [degrees] . [DOI: 10.1115/1.1408306] Keywords: Fluid Machinery, Wave Power Conversion, Air Turbine, Self-Pitch-Controlled Blade, Ocean Wave