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71.
72.
Gregor P. Henze 《Canadian Metallurgical Quarterly》2002,8(4):133-141
This paper describes an investigation of the economic performance of a central chiller plant with thermal energy storage (TES) operating in a hotel in California and an office building in Wisconsin for the following three conventional control strategies: chiller-priority, constant-proportion, and storage-priority control. Since all control strategies depend on properly selected design parameters, the storage and chiller capacities as the primary design parameters were varied over a wide range, and the life-cycle economic feasibility of each possible design was assessed over a 20-year economic life using the net present value method. Measured cooling and weather data for both buildings were used in annual calculations to determine annual utility cost savings on the basis of one of four artificial rate structures. Trends in the life-cycle economic performance of TES systems as a function of chiller and storage capacities were revealed, and design guidelines were developed. 相似文献
73.
Dr. Matthew A. B. Baker Dr. Nejc Rojko Dr. Bríd Cronin Prof. Gregor Anderluh Prof. Mark I. Wallace 《Chembiochem : a European journal of chemical biology》2014,15(14):2139-2145
Equinatoxin II (EqtII), a sea anemone cytolysin, is known to oligomerize to form pores that spontaneously insert into membranes. Crystallographic and cryo‐EM studies of structurally similar cytolysins offer contradictory evidence for pore stoichiometry. Here we used single‐molecule photobleaching of fluorescently labeled EqtII to determine the stoichiometry of EqtII oligomers in supported lipid bilayers. A frequency analysis of photobleaching steps revealed a log‐normal distribution of stoichiometries with a mean of 3.4±2.3 standard deviations. Comparison of our experimental data with simulations of fixed stoichiometries supports our observation of a heterogeneous distribution of EqtII oligomerization. These data are consistent with a model of EqtII stoichiometry where pores are on average tetrameric, but with large variation in the number of subunits in individual pores. 相似文献
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75.
In this note we show how the theory of one-sided coupled operator matrices developed by K.-J. Engel [6-8] can be applied to boundary control problems. We illustrate the abstract results by considering the one-dimensional heat equation with dynamic boundary conditions and boundary control. 相似文献
76.
Magnetic maghemite nanoparticles in the form of nanosheets were prepared by a topotactic transformation during the dehydroxylation of a γ-FeO(OH) precursor. The precursor was synthesized from tetrapyridin Fe(II) chloride (Fe(py)4Cl2). The nanosheets are several hundreds of nanometers wide, and less than 5 nm thick; they frequently bend and curl at the edges; they are nanocrystalline; and they are composed of smaller maghemite nanostructured domains, from a few nanometers up to several tens of nanometers wide. 相似文献
77.
This study aimed at characterising 606 crossbred pigs of three commercially available breed types in terms of their carcass and meat quality. Breed G and H were German Large White (LW) × German Landrace (LR) sows sired with Pietrain (PI) boars, i.e. PI × (LW × LR). Breed S was 25% Duroc (DU), i.e. PI × (DU × LR). Most of the parameters were affected by breed and/or date of slaughter. The meat of crossbred pigs with 25% Duroc proportion appeared most favourable because of higher intramuscular fat content, lower drip loss and higher sensory liking scores. Conductivity is closely related to drip loss while the data suggests that the relationship is dependent on breed and carcass weight. The application of conductivity and lean meat yield thresholds to select carcasses with uniform and superior meat quality effectively decreased drip loss and increased intramuscular fat content as well as sensory liking scores. The variation of meat quality traits remains high, though. 相似文献
78.
Gregor Snelting 《Acta Informatica》1991,28(5):411-445
We present the theory of context relations. Context relations are a method for incremental semantic analysis in language-specific editors, which is able to handle incomplete program fragments. The algorithm is generated from the definition of a language's static semantics and is based on inference rules and order-sorted unification. The paper presents the underlying mathematical theory, optimal incremental analysis algorithms, handling of user-defined polymorphism and overloading, and implementation issues. It is intended as the concluding report on a by now mature concept, which has successfully been used to generate efficient incremental type inferencers for languages like ADA and Fortran 8x. 相似文献
79.
Summary. A complete communication system is broken down into a number of protocol layers each of which provides services to the layer
above it and uses services provided by its underlying layer. A service specification defines a particular ordering of the
operations that a given layer provides to the layer above it. The active elements in each layer are called entities and they
use a protocol in order to implement their service definition. On the basis of this relation between the service and protocol
concepts we have developed algorithms for deriving protocol entity specifications from a formal service specification. The
derived protocol entities ensure the correct ordering of the service primitives by exchanging synchronization messages through
an underlying communication medium. This paper presents an extended version of our earlier derivation algorithms. This version
of the algorithm can handle all operators and unrestricted process invocation and recursion as defined by basis LOTOS. The
correctness of this derivation algorithm is formally proved.
Received: January 1992 / Accepted: February 1996 相似文献
80.