Quantum Bayesian implementation and revelation principle

Bayesian implementation concerns decision making problems when agents have incomplete information. This paper proposes that the traditional sufficient conditions for Bayesian implementation shall be amended by virtue of a quantum Bayesian mechanism. In addition, by using an algorithmic Bayesian mechanism, this amendment holds in the macro world. More importantly, we find that the revelation principle is not always right by using the quantum and algorithmic Bayesian mechanisms.

A "double coincidence" search model of money

According to Engineer and Shi (1998, 2001) and Berentsen and Rocheteau (2003), the double coincidence of wants problem seems to be not essential to rationalize the use of money in a search theoretic framework. This paper analyzes an endogenous price search model of money where there is universal double coincidence of wants. The existence of a monetary equilibrium depends, essentially, on the asymmetry in the role played by economic agents in the exchange and production processes. In particular, entrepreneurs are assumed to produce a fixed amount of a divisible consumption good by means of labour services provided by workers. Entrepreneurs can offer a co-operative (barter) contract or a monetary contract to workers. Under the co-operative contract real wages are determined in the labour exchange sector, while in the monetary regime real wages are determined in the commodity exchange sector. The monetary contract is proved to be an equilibrium strategy provided that: (i) the workers' labour disutility is sufficiently high and/or (ii) the entrepreneurs' bargaining power in the commodity market is sufficiently large relative to their bargaining power in the labour market. The rationale for money comes from the fact that entrepreneurs use it as an instrument to maximize their output share.

External debt management in Romania

This paper approaches the evolution of Romania’s foreign debt in three periods of time: during Nicolae Ceausescu regime, in the transition period and the one which followed the adhesion to European Union. For all three periods the external debt management had to deal with different circumstances: the sharp increase of real interest rates from the 1980s, the lack of credibility on international financial markets from the 1990s or the recent global crisis. We conclude that political regime, the efficiency of the allocation of the borrowed funds or the international context played major roles in the external debt management.

Intertemporal substitution and durable goods: long-run data

In this paper, we use long-run annual data to estimate the intertemporal elasticity of substitution while accounting for the intra-temporal substitution between nondurable consumption goods and durable consumption goods. We apply a two-step procedure that combines a cointegration approach to preference parameter estimation with Generalized Method of Moments.

The Ontological Basis of Strong Artificial Life

This article concerns the claim that it is possible to create living organisms, not merely models that represent organisms, simply by programming computers ("virtual" strong alife). I ask what sort of things these computer-generated organisms are supposed to be (where are they, and what are they made of?). I consider four possible answers to this question: (a) The organisms are abstract complexes of pure information; (b) they are material objects made of bits of computer hardware; (c) they are physical processes going on inside the computer; and (d) they are denizens of an entire artificial world, different from our own, that the programmer creates. I argue that (a) could not be right, that (c) collapses into (b), and that (d) would make strong alife either absurd or uninteresting. Thus, "virtual" strong alife amounts to the claim that, by programming a computer, one can literally bring bits of its hardware to life

Mobile consultant: Combining total mobility with constant access

Minimizing the time required for a medical consultant to offer his/her expert opinion, can be viewed as a life-saving procedure. We have designed and tested an integrated system that will allow a medical consultant to freely move either within, or outside the hospital, while still maintaining constant contact with the patients via videoconferencing and high-resolution imaging. The above system is explained in this paper, along with its advantages and its potential limitations. Conclusively, we demonstrate that such a system further increases the mobility of the medical consultant, while improving the healthcare service

Expression, purification, crystallization and preliminary X-ray diffraction analysis of conjugated bile salt hydrolase from Bifidobacterium longum

Conjugated bile salt hydrolase (BSH) catalyses the hydrolysis of the amide bond that conjugates bile acids to glycine and to taurine. The BSH enzyme from Bifidobacterium longum was overexpressed in Escherichia coli BL21(DE3), purified and crystallized. Crystallization conditions were screened using the hanging-drop vapour-diffusion method. Crystal growth, with two distinct morphologies, was optimal in experiments carried out at 303 K. The crystals belong to the hexagonal system, space group P622 with unit-cell parameters a = b = 124.86, c = 219.03 Angstrom, and the trigonal space group P321, with unit-cell parameters a = b = 125.24, c = 117.03 Angstrom. The crystals diffracted X-rays to 2.5 Angstrom spacing. Structure determination using the multiple isomorphous replacement method is in progress

Simulation study of the localization of a near-surface crack using an air-coupled ultrasonic sensor array

The importance of Non-Destructive Testing (NDT) to check the integrity of materials in different fields of industry has increased significantly in recent years. Actually, industry demands NDT methods that allow fast (preferably non-contact) detection and localization of early-stage defects with easy-to-interpret results, so that even a non-expert field worker can carry out the testing. The main challenge is to combine as many of these requirements in one single technique. The concept of acoustic cameras, developed for low frequency NDT, meets most of the above mentioned requirements. These cameras make use of an array of microphones to visualize noise sources by estimating the Direction Of Arrival (DOA) of the impinging sound waves. Until now, however, because of limitations in frequency range and lack of integrated nonlinear post-processing, acoustic camera systems have never been used for the localization of incipient damage. The goal of the current paper is to numerically investigate the capabilities of locating incipient damage by measuring the nonlinear airborne emission of the defect using a non-contact ultrasonic sensor array. We will consider a simple case of a sample with a single near-surface crack and prove that after efficient excitation of the defect sample, the nonlinear defect responses can be detected by a uniform linear sensor array. These responses are then used to determine the location of the defect by means of three different DOA algorithms. The results obtained in this study can be considered as a first step towards the development of a nonlinear ultrasonic camera system, comprising the ultrasonic sensor array as hardware and nonlinear post-processing and source localization software.status: publishe

Vetenskaplig expertis och nordområdets naturresurser

The essay reflects on political pressures exerted by and on scientists and technologists acting as advisors on political and economic matters of the high north.It uses two case studies to do this. One consists in the group of scientists from several nations who engaged as advisors to their foreign offices in the process leading up tothe ratification of the Spitsbergen/Svalbard treaty in 1920. The focus is on the discourse regarding hunting, mining and nature protections on these islands. The second case is the way technologists and geological scientists were engaged in the industrialisation of the USSR. These contexts of course differ in scale and in many other ways but are similar in certain respects. The discussion is centred on the problems of technocracy which is commented based on the Frankfurt school's elaborations on the open society and differing interpretations of technological determinism. This is related further to contemporary contentions over the balance between scientific based environmental stewardship and technological management in northern raw material extraction

On the Estimation of Supply and Demand Elasticities of Agricultural Commodites

The report provides a literature review on the topic of estimation of demand and supply elasticities. To this end, it starts the discussion by summarizing the main facets of production theory and consumer theory to introduce the concept of elasticities, with examples of different types of elasticities most utilized in the literature. Next, it discusses the identification problem in estimating elasticities, i.e. the issue of having to solve for unique values of the parameters of the structural model from the values of the parameters of the reduced form of the model. It summarizes various methodologies employed in the literature to solve this problem and gives practical examples. These solutions include, but are not limited to, using instrumental variables, adopting a recursive structure, holding demand constant, and imposing inequality constraints in order to restrict the domain of estimates.