Synchronous and Sequential Strategies in the Process Design of Cascade Equipment

Cascade or multistage equipment is characterized by the repetition of similar equipment elements in series. Process design, resulting into the main geometric and kinematic dimensions of the equipment, makes use of different strategies. These strategies, based on a process description, the (equality- and inequality) constraints and the number of degrees of freedom of the mathematical system, which describes the process, can be divided in synchronous- and sequential procedures. In a synchronous strategy no a priori requirements are made as to the distribution of a given process variable over the stages, so that the equipment dimensions are obtained simultaneously. In contrast to this a sequential strategy makes use of a priori statements resulting into stage-to-stage calculations and a decreasing number of degrees of freedom. The general theory presented with detailed information on process description, constraints and degrees of freedom, has been applied to the process design of a multi-stage centrifugal compressor

On Further Generalization of the Rigidity Theorem for Spacetimes with a Stationary Event Horizon or a Compact Cauchy Horizon

A rigidity theorem that applies to smooth electrovac spacetimes which represent either (A) an asymptotically flat stationary black hole or (B) a cosmological spacetime with a compact Cauchy horizon ruled by closed null geodesics was given in a recent work \cite{frw}. Here we enlarge the framework of the corresponding investigations by allowing the presence of other type of matter fields. In the first part the matter fields are involved merely implicitly via the assumption that the dominant energy condition is satisfied. In the second part Einstein-Klein-Gordon (EKG), Einstein-[non-Abelian] Higgs (E[nA]H), Einstein-[Maxwell]-Yang-Mills-dilaton (E[M]YMd) and Einstein-Yang-Mills-Higgs (EYMH) systems are studied. The black hole event horizon or, respectively, the compact Cauchy horizon of the considered spacetimes is assumed to be a smooth non-degenerate null hypersurface. It is proven that there exists a Killing vector field in a one-sided neighborhood of the horizon in EKG, E[nA]H, E[M]YMd and EYMH spacetimes. This Killing vector field is normal to the horizon, moreover, the associated matter fields are also shown to be invariant with respect to it. The presented results provide generalizations of the rigidity theorems of Hawking (for case A) and of Moncrief and Isenberg (for case B) and, in turn, they strengthen the validity of both the black hole rigidity scenario and the strong cosmic censor conjecture of classical general relativity.Comment: 25 pages, LaTex, a shortened version, including a new proof for lemma 5.1, the additional case of Einstein-Yang-Mills-Higgs systems is also covered, to appear in Class. Quant. Gra

PORTABILITY-BASED SOFTWARE TECHNOLOGY FOR PROGRAMMING MICROPROCESSORS AND PDP-11 COMPUTERS

The reasons of developing the software technological system applied at the Department of Instrumentation and Metrology, Technical University, Budapest, will be surveyed, as well as the problems in solving thereof the system gives support. The system essentially relies on the CDL language and program portability based techniques. The main purpose of the system is to support the programming process of microprocessor equipments. The efficiency of the programs developed has proved that, with appropriate technological background, reliable, quick, and small memory programs can be produced even in high level language

The effect of sustainability on the information search behaviour of Hungarian consumers through the practice of food purchasing

In the study we aim to model the information search behaviour of Hungarian consumers committed to sustainable consumption through the practice of food purchasing. To reach our goal we examined the logic of Grunert-Wills information search model.In our research the information search behaviour of “Trend followers” was investigated. To reach the mentioned group, data collection was carried out by the method of quota sampling, where quotas were defined according to characteristics of value system based lifestyle segments discovered in a 2011 national representative research by us. Through the analysis one-variable statistics and contingency table analysis were carried out.Our results prove the followings: (i) the logic of Grunert-Wills model is suitable for describing the information search behaviour of conscious consumers. (ii) Lifestyle has a highlighted effect on information search behaviour

Dynamic Scaling of Width Distribution in Edwards--Wilkinson Type Models of Interface Dynamics

Edwards--Wilkinson type models are studied in 1+1 dimensions and the time-dependent distribution, P_L(w^2,t), of the square of the width of an interface, w^2, is calculated for systems of size L. We find that, using a flat interface as an initial condition, P_L(w^2,t) can be calculated exactly and it obeys scaling in the form _\infty P_L(w^2,t) = Phi(w^2 / _\infty, t/L^2) where _\infty is the stationary value of w^2. For more complicated initial states, scaling is observed only in the large- time limit and the scaling function depends on the initial amplitude of the longest wavelength mode. The short-time limit is also interesting since P_L(w^2,t) is found to closely approximate the log-normal distribution. These results are confirmed by Monte Carlo simulations on a `roof-top' model of surface evolution.Comment: 5 pages, latex, 3 ps figures in a separate files, submitted to Phys.Rev.

A Note on Hartle-Hawking Vacua

The purpose of this note is to establish the basic properties--- regularity at the horizon, time independence, and thermality--- of the generalized Hartle-Hawking vacua defined in static spacetimes with bifurcate Killing horizon admitting a regular Euclidean section. These states, for free or interacting fields, are defined by a path integral on half the Euclidean section. The emphasis is on generality and the arguments are simple but formal.Comment: 5 pages, LaTe