Investition bei Unsicherheit als Erklärung für hohe implizite Diskontraten bei Energiesparinvestitionen

Zusammenfassung Die Tatsache, daß Konsumenten (und auch Unternehmen) hohe implizite Diskontraten bei der Entscheidung über Energiesparinvestitionen verwenden, wird häufig beobachtet. Dies wird fast einhellig als Marktversagen angesehen und hat viele Analytiker dazu veranlaßt, entweder für öffentliche oder bezuschußte Energiesparinvestitionen zu plädieren. In dieser Arbeit wird die Theorie der Realoptionen auf ein bekanntes Beispiel angewandt: der Wahl zwischen konventioneller Glühbirne und Sparlampe bei unterstellter Risikoneutralität des Entscheidungsträgers. Es zeigt sich, daß die dem Wert der Option des Abwartens und Aufschiebens der Investition Rechnung tragenden impliziten Diskontraten nahe den beobachteten Werten liegen. Deshalb bedarf die Schlußfolgerung eines Marktversagens aus hohen impliziten Diskontraten einer sorgfältigeren und feineren Analyse. Dies trifft a fortiori auf due Empfehlung von Energiesparprogrammen zu.Die Autoren sind zwei anonymen Gutachtern zu Dank für ihre konstruktiven Vorschläge verpflichtet     

Observation ofd-wave interference pattern:Short junction is crucial

The properties of a one-dimensional 0--Josephson junction, consiting of ans-d junction or selected boundaries between three suitably orientedd-wave superconductors, are studied. It is shown that ad-wave type interference pattern can only be observed in the field-modulated critical current if the junction is short compared to the Josephson penetration depth. However, the behavior of a 0- junction is found to be indistinguishable from that of a 0-junction betweens-wave superconductors in the long junction limit, due to the formation of a -vortex.     

Microstructure Development and Property Improvement in Mill Products Produced from Ingot Metallurgy and Powder Metallurgy Ni-Based Superalloys of the Same Chemical Composition

Despite projected inroads from competing materials Ni-based superalloys remain the material of choice in the hot sections of advanced gas turbine engines. In this paper microstructural development and improvement of mechanical properties in mill products produced by ingot metallurgy (IM) and powder metallurgy (PM) techniques are discussed. Particular attention is given to approaches to improvement in ingot ductility. Thermomechanical treatment schemes used during forging of a complex-alloyed Ni-based superalloy are recommended. It is demonstrated that the PM technique used for production of this complex-alloyed superalloy is a promising approach. On the basis of the studies carried out the salient features of the structure of material produced both by both IM and PM techniques have been defined. The mechanical properties of two versions of an advanced Ni-base superalloy produced by IM and PM techniques are discussed. The best combination of mechanical properties are exhibited by a PM material with a necklace structure; and this latter structure is superior to a fine grained structure for IM product also.     

New high-pressure Sr-Ca-Cu-O compounds and their superconducting properties

It is shown for (Sr, Ca)_1–y CuO_2.00+z (nominal composition) superconductors fabricated under a high pressure of 5 GPa and at 930°C that, as z increases, the Meissner fraction increases from a few percent to 20% and then starts to decrease. In the X-ray powder diffraction pattern for the sample with the maximum Meissner fraction, it is obvious that the infinite-layer structure has been decomposed and a new structure becomes the major phase. It appears that the new structure is the 0223 structure which consists of rock-salt and the infinite-layer type blocks. This material is likely to be a new superconducting cuprate.     

(Pre)kernel catchers for cooperative games

The paper provides a new (pre)kernel catcher in that the relevant set always contains the (pre)kernel. This new (pre)kernel catcher gives rise to a better lower bound _*** such that the kernel is included in strong -cores for all real numbers not smaller than the relevant bound _***.The research for this paper was done under the sponsorship of both the Dutch Organization for the Advancement of Scientific Research (NWO) and the National Science Council (NSC) of Taiwan during a stay of Dr. Chih Chang at the University of Twente, Enschede, The Netherlands.     

Lambda-Calculus with Director Strings

We present a name free -calculus with explicit substitutions, based on a generalised notion of director strings. Terms are annotated with information – directors – that indicate how substitutions should be propagated. We first present a calculus where we can simulate arbitrary -reduction steps, and then simplify the rules to model the evaluation of functional programs (reduction to weak head normal form). We also show that we can define the closed reduction strategy. This is a weak strategy which, in contrast with standard weak strategies, allows certain reductions to take place inside -abstractions thus offering more sharing. Our experimental results confirm that, for large combinator-based terms, our weak evaluation strategies out-perform standard evaluators. Moreover, we derive two abstract machines for strong reduction which inherit the efficiency of the weak evaluators.Projet Logical, Pôle Commun de Recherche en Informatique du plateau de Saclay, CNRS, École Polytechnique, INRIA, Université Paris-Sud.     

Maximizing pseudoconvex transportation problem: a special type

The paper discusses a non-concave fractional programming problem aiming at maximization of a pseudoconvex function under standard transportation conditions. The pseudoconvex function considered here is the product of two linear functions contrasted with a positive valued linear function. It has been established that optimal solution of the problem is attainable at an extreme point of the convex feasible region. The problem is shown to be related to indefinite quadratic programming which deals with maximization of a convex function over the given feasible region. It has been further established that the local maximum point of this quadratic programming problem is the global maximum point under certain conditions, and its optimal solution provides an upper bound on the optimal value of the main problem. The extreme point solutions of the indefinite quadratic program are ranked to tighten the bounds on the optimal value of the main problem and a convergent algorithm is developed to obtain the optimal solution.     

Phonon Raman scattering of R2CuO4 (R = Pr, Nd, Sm, and Gd)

For Gd₂CuO₄, a new symmetry-forbidden phonon for the tetragonal T structure is observed. This implies that oxygen in the CuO₂ plane is locally distorted along the CuO₂ plane. Such distortion has never been observed for other T-type superconductors, which show superconductivity by Ce doping. The disappearance of superconductivity for Gd can be correlated with the appearance of the distortion due to oxygen in the CuO₂ plane.     

Evolution of the Electronic Structure of Y-Bi-2212 from the Antiferromagnetic to the Superconducting Regime

The phase diagram of the cuprate superconductors at low doping and low temperatures in the non-superconducting state is dominated by magnetic correlations. When increasing the hole concentration in the CuO₂-planes from zero an antiferromagnetic (AF) insulating phase is followed for hole concentrations greater than approximately 0.08 by the superconducting phase. For the range of doping in between the situation is less clear and several models exist. For Bi₂Sr₂Y _x Ca_1–xCu₂O₈ in the range of Y-concentrations 0.9 < x < 0.0 the evolution of the electronic structure starting from the AF phase at x = 0.9, which in this respect can be regarded as the parent compound of the superconducting phase, and its gradual development into the superconducting range can be studied on one system. In this series the CuO₂-planes are kept embedded in a nearly identical environment for each hole concentration. Especially the results from the AF phase deviate from former reports attained mainly from oxychlorides.     

Detecting Explosions with Ionizing-Radiation Measurement of Scattered 137Cs γ-Rays

Measurements have been made on the spectra of the rays scattered by trotyl and by substances similar to it in density and composition placed behind various shielding materials. The experiments check the scope for implementing -tomography for observing and identifying explosives.     

Density of α-pinene, Β-pinene,limonene, and essence of turpentine

Densities of ga-pinene, -pinene, limonene, and essence of turpentine have been measured at 293.15, 298.15, 303.15, 308.15, and 313.15 K, at atmospheric pressure, with a mechanical oscillator densimeter. Benzene and cyclohexane were used as calibration fluids. The precision is of the order of 0.01 kg · m^–3, while the accuracy is estimated to be 0.1%. A linear representation of the variation of the density with temperature reproduces the experimental data within 0.2%.     

Effects of measurement errors on sample monitoring reliability

Results are presented on the effects of measurement errors on items in routine production as regards the reliability of results on sampling inspection obtained by Monte Carlo simulation. The customers and the makers risks are examined in relation to the distributions of the measurement errors and the values of them.Translated from Izmeritelnaya Tekhnika, No. 12, pp. 8–11, December, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Thermophysical Properties of the Zr–0.01Nb Alloy at Various Heating Rates and Repeated Cycles of Heating–Cooling

The results of an experimental study of the heat capacity, enthalpy, electrical resistivity, and spectral emissivity (for the wavelength of 0.65 m) of the Zr–0.01Nb alloy in the temperature range from 900 to 2000 K are presented. The study was carried out using subsecond pulse heating of the samples by passing electrical current through them. Experiments were conducted at different heating rates (10³ to 10⁴K·s^–1), and a series of experiments consisted of several cycles of pulse heating and subsequent cooling. The effect of these parameters on the temperature dependence of thermophysical properties in the region of the –transition was studied. With an increase in the heating rate, the temperature of the – transition, and the maximum in the heat capacity shifted to higher temperatures. There are significant differences in properties over the temperature range of the – transition for the various heating cycles.     

Solid-liquid phase equilibria of (α-methylnaphthalene + β-methylnaphthalene) and (chlorobenzene + bromobenzene) systems under high Pressures

Solid-liquid phase equilibria of the (-methylnaphthalene + -methylnaphthalene) and the (chlorobenzene + bromobenzene) systems have been investigated at temperatures from 278 to 343 K and pressures up to 500 MPa using a high-pressure optical vessel. The uncertainties of the measurements of temperature, pressure, and composition were within ±0.1 K, ±0.5 MPa, and ±0.001 mole fraction, respectively. In both systems, the freezing and melting pressures at a constant composition increase almost linearly with increasing temperatures. In the former system, where the two components can form a solid solution with one another to a limit extent, the eutectic point shifts to a higher temperature and to a -methylnaphthalene-rich composition with increasing pressures. In the latter system, where the two components are completely soluble in each other in the solid phase, the freezing points of all mixtures lie between those of the pure components at each pressure. It is found that the coexistence curves obtained can be expressed by a quadratic equation in pressure.     

Effective Łojasiewicz inequalities in semialgebraic geometry

The main result of this paper can be stated as follows: letV ⁿ be a compact semialgebraic set given by a boolean combination of inequalities involving only polynomials whose number and degrees are bounded by someD > 1. LetF, G[X₁,, X_n] be polynomials with degF, degG D inducing onV continuous semialgebraic functionsf, g:VR. Assume that the zeros off are contained in the zeros ofg. Then the following effective ojasiewicz inequality is true: there exists an universal constantc ₁ and a positive constantc ₂ (depending onV, f,g) such that for allxV. This result is generalized to arbitrary given compact semialgebraic setsV and arbitrary continuous functionsf,g:V . An effective global ojasiewicz inequality on the minimal distance of solutions of polynomial inequalities systems and an effective Finiteness Theorem (with admissible complexity bounds) for open and closed semialgebraic sets are derived.     

The dependence of stress intensity factors and weight functions on elastic constants

We investigate the dependence of stress intensity factors (SIFs) on elastic constants in two-dimensional elastic isotropic bodies. Bueckners weight function theory is used for the derivation of the dependence of SIFs on elastic constants. The dependence of SIFs on Poissons ratio shows up when the resultant tractions on each of the contours L _k separately is not zero in multiply connected bodies. As an example we calculate K ₁ for Griffith crack under concentrated loading applied on the upper crack face.     

Chemical Durability of Waste Fluorescent Glass and Shell–Derived Glass-Ceramics

In order to obtain glass-ceramics reinforced by -wollastonite, pressed specimens prepared by powdered waste fluorescent glass and refuse shell dumped in the seashore were heat-treated at 800°C, 900°C, and 1000°C. Chemical stability of the heat-treated specimens was analyzed by weight changes and by observation of surface morphology and composition, by field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy. Chemical durability of the samples, especially at the glass-matrix area, was decreased with an increase in the heat-treatment temperature from 800°C to 1000°C.     

Novel methodology to investigate superconducting dielectric resonators

An analytical method is presented for investigating the resonant behavior of a c-axis oriented YBa₂Cu₂O_7–(0) thin film on a resonator composed of LaAlO₃ (001). The concept of the negative dielectric medium for a superconductor is introduced within the framework of the two-fluid model, which permits us to treat a superconductor as any other penetrable materials so that only its electromagnetics are concerned. A conformai transformation is further suggested to map the original open boundary-value problem to a closed one. This not only makes the original problem readily solvable by using the variational technique, but is also a powerful tool for analyzing some kinds of problems such as the propagation characteristics of the superconducting microstripe and coplanar waveguide structures.