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31.
This paper introduces a compositional semantics of locativeprepositional phrases which is based on a vector space ontology.Model-theoretic properties of prepositions like monotonicity andconservativity are defined in this system in a straightforward way.These notions are shown to describe central inferences with spatialexpressions and to account for the grammaticality of prepositionmodification. Model-theoretic constraints on the set of possibleprepositions in natural language are specified, similar to the semanticuniversals of Generalized Quantifier Theory. 相似文献
32.
Electricity can be produced directly with reverse electrodialysis (RED) from the reversible mixing of two solutions of different salinity, for example, sea and river water. The literature published so far on RED was based on experiments with relatively small stacks with cell dimensions less than 10 × 10 cm(2). For the implementation of the RED technique, it is necessary to know the challenges associated with a larger system. In the present study we show the performance of a scaled-up RED stack, equipped with 50 cells, each measuring 25 × 75 cm(2). A single cell consists of an AEM (anion exchange membrane) and a CEM (cation exchange membrane) and therefore, the total active membrane area in the stack is 18.75 m(2). This is the largest dimension of a reverse electrodialysis stack published so far. By comparing the performance of this stack with a small stack (10 × 10 cm(2), 50 cells) it was found that the key performance parameter to maximal power density is the hydrodynamic design of the stack. The power densities of the different stacks depend on the residence time of the fluids in the stack. For the large stack this was negatively affected by the increased hydrodynamic losses due to the longer flow path. It was also found that the large stack generated more power when the sea and river water were flowing in co-current operation. Co-current flow has other advantages, the local pressure differences between sea and river water compartments are low, hence preventing leakage around the internal manifolds and through pinholes in the membranes. Low pressure differences also enable the use of very thin membranes (with low electrical resistance) as well as very open spacers (with low hydrodynamic losses) in the future. Moreover, we showed that the use of segmented electrodes increase the power output by 11%. 相似文献
33.
Robert Baggen José Pedro Correia Katrin Schill Joost Visser 《Software Quality Journal》2012,20(2):287-307
We provide an overview of the approach developed by the Software Improvement Group for code analysis and quality consulting
focused on software maintainability. The approach uses a standardized measurement model based on the ISO/IEC 9126 definition
of maintainability and source code metrics. Procedural standardization in evaluation projects further enhances the comparability
of results. Individual assessments are stored in a repository that allows any system at hand to be compared to the industry-wide
state of the art in code quality and maintainability. When a minimum level of software maintainability is reached, the certification
body of TüV Informationstechnik GmbH issues a Trusted Product Maintainability certificate for the software product. 相似文献
34.
Parameter-study on the influence of steel fibers and coarse aggregate content on the fresh properties of self-compacting concrete 总被引:7,自引:0,他引:7
Self-compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers bridge cracks, retard their propagation, and improve several characteristics and properties of the concrete. Fibers are known to significantly affect the workability of concrete. Therefore, an investigation was performed to compare the properties of plain SCC and SCC reinforced with steel fibers. Two mixtures of SCC with different aggregate contents were used as reference. Each of the concretes was tested with four types of steel fibers at different contents in order to answer the question to what extent the workability of SCC is influenced. The slump flow, a fiber funnel and the J-ring test were used to evaluate the material characteristics of the fresh concrete. This paper discusses the suitability of the applied test methods and the effect of the coarse aggregate content, the content and type of steel fibers on the workability of SCC. 相似文献
35.
K. Reichling M. Raupach J. Broomfield J. Gulikers P. V. Nygaard U. Schneck G. Sergi 《工业材料与腐蚀》2013,64(2):128-134
Full surface surveys which are likely to include e.g. a deterioration and potential mapping as well as a cover depth survey, should be the base to identify critical areas which are suspect to be suffering from reinforcement corrosion 1 . Localised assessment in these areas should give further information about the type and extent of deterioration. It should include the determination of the chloride profile beyond the cover depth, the depth of carbonation and a direct visual assessment of the steel reinforcement by breaking away the cover concrete at selected locations. Further valuable information may be collected by determining the water content of the concrete or performing corrosion rate measurements. Within this publication the essential methods for local detailed inspections are discussed regarding the application and interpretation of the results. An overview of the survey procedure is given in ref. 2 . 相似文献
36.
Schokker Marike C.; Keers Joost C.; Bouma Jelte; Links Thera P.; Sanderman Robbert; Wolffenbuttel Bruce H. R.; Hagedoorn Mari?t 《Canadian Metallurgical Quarterly》2010,29(4):438
Objective: Our aim was to determine whether the impact of upward and downward social comparison information on individuals' motivation to manage their diabetes is dependent on their regulatory focus (promotion or prevention focus) and self-efficacy. Design: The hypotheses were examined in a cross-sectional study. Patients with diabetes (N = 234) read a fictitious interview with a fellow patient, either an upward or a downward target, and they filled out questionnaires. Main Outcome Measures: Motivation to work on diabetes regulation. Results: High promotion-focused patients reported more motivation than low promotion-focused patients when confronted with the upward target (positive role model). High prevention-focused patients reported more motivation than low prevention-focused patients when confronted with the downward target (negative role model). This latter finding was qualified by patients' self-efficacy, as it applied only to patients with relatively high levels of self-efficacy. Conclusion: The current study highlights the importance of considering individual differences when using role models to encourage self-care activities in persons with diabetes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Coupled transformations occur in software evolution when multiple artifacts must be modified in such a way that they remain consistent with each other. An important example involves the coupled transformation of a data type, its instances, and the programs that consume or produce it. Previously, we have provided a formal treatment of transformation of the first two: data types and instances. The treatment involved the construction of type-safe, type-changing strategic rewrite systems. In this paper, we extend our treatment to the transformation of corresponding data processing programs.The key insight underlying the extension is that both data migration functions and data processors can be represented type-safely by a generalized abstract data type (GADT). These representations are then subjected to program calculation rules, harnessed in type-safe, type-preserving strategic rewrite systems. For ease of calculation, we use point-free representations and corresponding calculation rules.Thus, coupled transformations are carried out in two steps. First, a type-changing rewrite system is applied to a source type to obtain a target type together with (representations of) migration functions between source and target. Then, a type-preserving rewrite system is applied to the composition of a migration function and a data processor on the source (or target) type to obtain a data processor on the target (or source) type. All rewrites are type-safe. 相似文献
38.
Jeroen J.L.M. Cornelissen Matthias Fischer Rieko van Heerbeek Joost N.H. Reek Roeland J.M. Nolte 《Polymer》2004,45(22):7417-7430
Following up on previous preliminary communications the synthesis of a series of block copolymers by applying amine end-capped polymers as initiators for the nickel(II) catalyzed polymerization of isocyanides is reported. Using a polystyrene derivative as the initiator, superamphiphiles containing a hydrophobic polystyrene tail and a charged helical polyisocyanide headgroup were prepared. Under proper conditions these superamphiphiles self-assembled in water to give a variety of aggregate morphologies, among which are superhelical architectures. Initiators derived from carbosilane dendritic wedges gave block copolymers with a unique combination of structural elements, i.e. a flexible dendritic block and a rigid polyisocyanide block. Block copolymers derived from the 3rd generation dendrimers form well-defined micellar aggregates in the presence of Ag+ ions. These aggregates have been used to construct nanoarrays of metallic silver. 相似文献
39.
Hierarchical Zeolite: Catalyst Design by NH4OH Treatment of USY Zeolite (Adv. Funct. Mater. 46/2015) 下载免费PDF全文
Joost Van Aelst Danny Verboekend An Philippaerts Nicolas Nuttens Mert Kurttepeli Elena Gobechiya Mohamed Haouas Sreeprasanth P. Sree Joeri F. M. Denayer Johan A. Martens Christine E. A. Kirschhock Francis Taulelle Sara Bals Gino V. Baron Pierre A. Jacobs Bert F. Sels 《Advanced functional materials》2015,25(46):7244-7244
40.
Joost Van Aelst Danny Verboekend An Philippaerts Nicolas Nuttens Mert Kurttepeli Elena Gobechiya Mohamed Haouas Sreeprasanth P. Sree Joeri F. M. Denayer Johan A. Martens Christine E. A. Kirschhock Francis Taulelle Sara Bals Gino V. Baron Pierre A. Jacobs Bert F. Sels 《Advanced functional materials》2015,25(46):7130-7144
Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra‐Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH (0.02 m ) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2–6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid‐catalyzed isomerization of α‐pinene and the metal‐catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties. 相似文献