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41.
42.
The analysis of mechanisms which affect the formation of agglomerates and determine the granulation process in a broad sense encounters difficulties related to the many ways of the formation of granules. The aim of the study was to perform a qualitative and quantitative analysis of granulation mechanisms with special reference to agglomerates’ disintegration in the disc granulation process. This paper contains an analysis of disintegration mechanisms (abrasion and crushing) of agglomerates during the disc granulation of dolomite. The analysis of the mechanisms taking place during the process concerns the granulation stage after wetting. During the research, each time after the wetting stage, the size fraction 10–12.5 mm was substituted with an analogous fraction wetted by means of an aqueous solution of a coloring agent and the process was continued. After the specified time of granulation, the obtained product was sieved through laboratory sieves and then the content of the provided coloring agent in different size fractions was analyzed by means of a spectrophotometer. Measuring the absorbance of the analyzed samples and granulometric composition of the bed, the level and cause of the migration of material of the tested fraction into other size classes were determined, and at the same time, the occurring granulation mechanisms were analyzed. The proposed model and measurement method consisting of determining the absorbance of the tested granulometric fraction enable the qualitative and quantitative analysis of granulation mechanisms are encountered during the carrying-out of the process after wetting the bed. 相似文献
43.
A. Gawęcki 《Acta Mechanica》1996,116(1-4):111-122
Summary Convexity of elastic response regions in external load space for inelastic structures has been analyzed. Theoretical considerations have been carried out using the discrete matrix notation and piece-wise linear approximation proposed by Maier (cf. [10]). A necessary condition for the non-convexity of the elastic surface has been derived. Several examples including nonlinear elastic-plastic materials, linear elastic-plastic structures with unilateral constraints, and also slackened-linear elastic-plastic structures are presented and discussed. 相似文献
44.
A problem of allocating resources of a grid to workflow applications is considered. The problem consists, generally, in allocating
distributed grid resources to tasks of a workflow in such a way that the resource demands of each task are satisfied. Grid
resources are divided into computational resources and network resources. Computational tasks and transmission tasks of a
workflow are distinguished. We present a model of the problem, and an algorithm for finding feasible resource allocations.
A numerical example is included, showing the importance of the resource allocation phase on a grid. Some conclusions and directions
for future research are given. 相似文献
45.
46.
Katarzyna TyszczukAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):899-905
The properties of the lead film electrode designed for adsorptive stripping voltammetric measurements of organic compounds were examined by electrochemical and microscopic techniques. The effect of Pb(II) concentration, the influence of deposition potential and time of the lead film formation on the determination of bleomycin at an in situ lead-coated glassy carbon electrode have been studied. Atomic force microscopy (AFM) was used to characterize the Pb crystallite growth on the glassy carbon surface. The morphology of the deposits was evaluated and its influence on the bleomycin responses was discussed. 相似文献
47.
Tristan Roussillon Hervé Piégay Isabelle Sivignon Laure Tougne Franck Lavigne 《Computers & Geosciences》2009,35(10):1992-2000
The shape of sedimentary particles is an important property, from which geographical hypotheses related to abrasion, distance of transport, river behavior, etc. can be formulated. In this paper, we use digital image analysis, especially discrete geometry, to automatically compute some shape parameters such as roundness, i.e. a measure of how much the corners and edges of a particle have been worn away.In contrast to previous work in which traditional digital images analysis techniques, such as Fourier transform, are used, we opted for a discrete geometry approach that allowed us to implement Wadell's original index, which is known to be more accurate, but more time consuming to implement in the field.Our implementation of Wadell's original index is highly correlated (92%) with the roundness classes of Krumbein's chart, used as a ground-truth. In addition, we show that other geometrical parameters, which are easier to compute, can be used to provide good approximations of roundness.We also used our shape parameters to study a set of pebbles digital images taken from the Progo basin river network (Indonesia). The results we obtained are in agreement with previous work and open new possibilities for geomorphologists thanks to automatic computation. 相似文献
48.
Bartosz Więckowski 《Journal of Logic, Language and Information》2016,25(2):215-268
A first-order language with a defined identity predicate is proposed whose apparatus for atomic predication is sensitive to grammatical categories of natural language (e.g., common nouns, verbs, adjectives, adverbs, modifiers). Subatomic natural deduction systems are defined for this naturalistic first-order language. These systems contain subatomic systems which govern the inferential relations which obtain between naturalistic atomic sentences and between their possibly composite components. As a main result it is shown that normal derivations in the defined systems enjoy the subexpression property which subsumes the subformula property with respect to atomic and identity formulae as a special case. The systems admit a proof-theoretic semantics which does not only apply to logically compound but also to atomic and identity formulae—as well as to their components. The potential of the defined systems for a meticulous first-order analysis of natural inferences whose validity crucially depends on expressions of some of the aforementioned categories is demonstrated. 相似文献
49.
NFMDB数据库管理系统是在 RDBMS的基础上扩充而成的 ,它支持非第一范式 NF2 (Nonfirst normal form)及多媒体数据类型。首先 ,分析了集中式和分离式字典系统的特点 ,并阐述了主动 DD和被动 DD的区别 ;其次 ,讨论了 NFMDB系统为处理 NF2问题而引入的关系字典、属性字典等字典的构造 ,并给出了部分结构描述 ;然后 ,用 create语句描述了一个关于 NF2 存储模式实例 ,同时以 select语句为例讨论了用关系字典和属性字典为基础转换多维 NF2 问题为平滑关系的算法 ,所有这些操作均在关系字典和属性字典中给出了相应的存储描述 ;最后 ,探讨了以关系方式存储 DD的优点以及 DD与 DBMS的关系。由此得出以扩充 DD系统为基础处理 NF2 问题是可行的。 相似文献
50.
Krzysztof Kurowski Jarek Nabrzyski Ariel Oleksiak Jan Węglarz 《Journal of Scheduling》2008,11(5):371-379
In this paper we address a multicriteria scheduling problem for computational Grid systems. We focus on the two-level hierarchical
Grid scheduling problem, in which at the first level (the Grid level) a Grid broker makes scheduling decisions and allocates
jobs to Grid nodes. Jobs are then sent to the Grid nodes, where local schedulers generate local schedules for each node accordingly.
A general approach is presented taking into account preferences of all the stakeholders of Grid scheduling (end-users, Grid
administrators, and local resource providers) and assuming a lack of knowledge about job time characteristics. A single-stakeholder,
single-criterion version of the approach has been compared experimentally with the existing approaches. 相似文献