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211.
212.
Danny De Schreye Bern Martens Gunther Sablon Maurice Bruynooghe 《Journal of Automated Reasoning》1991,7(3):337-358
We present a technique for the compilation of bottom-up and mixed logic derivations into PROLOG-programs. It is obtained as an extension of a program transformation technique called Compiling Control. We illustrate its applications in three different domains: solving numerical problems, integrity checking in deductive databases and theorem proving. The aim is to obtain efficient PROLOG programs for problems in which a non-top-down control is most appropriate.Work partly supported by ESPRIT BRA COMPULOG (project 3012).Supported by the Belgian I.W.O.N.L.-I.R.S.I.A. under contract number 5203. Author for correspondence.Supported by the Belgian National Fund for Scientific Research. 相似文献
213.
以尿素为前驱体,550℃热聚合反应5 h,制备了块状g-C_3N_4。然后将块状g-C_3N_4超声剥离得到片状g-C_3N_4,在g-C_3N_4纳米片上原位生长Cd S(直径约130 nm),从而制备了g-C_3N_4-Cd S异质结。g-C_3N_4-Cd S异质结的吸收边约505 nm处,与g-C_3N_4(约460 nm)相比具有明显的红移,可吸收更多的可见光。此外,g-C_3N_4-Cd S异质结可降解99%的罗丹明B,具有较高的光催化活性。 相似文献
214.
Bart Bogaerts Joachim Jansen Broes de Cat Gerda Janssens Maurice Bruynooghe Marc Denecker 《New Generation Computing》2016,34(3):193-220
Declarative systems aim at solving tasks by running inference engines on a specification, to free their users from having to specify how a task should be tackled. In order to provide such functionality, declarative systems themselves apply complex reasoning techniques, and, as a consequence, the development of such systems can be laborious work. In this paper, we demonstrate that the declarative approach can be applied to develop such systems, by tackling the tasks solved inside a declarative system declaratively. In order to do this, a meta-level representation of those specifications is often required. Furthermore, by using the language of the system for the meta-level representation, it opens the door to bootstrapping: an inference engine can be improved using the inference it performs itself.One such declarative system is the IDP knowledge base system, based on the language \(\rm FO(\cdot)^{\rm IDP}\), a rich extension of first-order logic. In this paper, we discuss how \(\rm FO(\cdot)^{\rm IDP}\) can support meta-level representations in general and which language constructs make those representations even more natural. Afterwards, we show how meta-\(\rm FO(\cdot)^{\rm IDP}\) can be applied to bootstrap its model expansion inference engine. We discuss the advantages of this approach: the resulting program is easier to understand, easier to maintain, and more flexible. 相似文献
215.
Maurice Margenstern 《International Journal of Parallel, Emergent and Distributed Systems》2017,32(4):309-330
In this paper, we prove that there is a weakly universal cellular automaton on the pentagrid with two states. This paper improves in some sense a previous result with three states. Both results make use of a la Moore neighbourhood. However, the result with three states is rotation invariant while the result of the present paper is not. In both cases, at each step of the computation, the set of non quiescent states has always infinitely many cycles. 相似文献
216.
The mathematical models and associated computer programs for analyzing a number of designs of overhead equipment such as simple catenary, compound catenary, stitched catenary, tunel equipment, and single-wire system, together with many possible variations are described. The programs are able to deal with up to four pantographs, and the initial conditions assumed are that the wires have their static equilibrium configurations and that the front pantograph is at the beginning of the first span touching the contact wire (or trolley wire) and moving tangentially to it. Any subsequent pantographs reach the beginning of the equipment after the start of the run and are then dealt with appropriately. The output of the programs list the input data, the total percentage contact loss between the panhead and contact wire in each span and the pantograph heights and contact forces at appropriate intervals of time. Graph plots of the pantograph heights and contact forces are also produced. The results of these programs are shown to give satisfactory agreement with previously published results obtained on a scaled model. 相似文献
217.
The expansion and extraction of rice bran 总被引:2,自引:0,他引:2
Expansion of rice bran as a pretreatment for solvent extraction was studied. It was found that the expanded bran showed no
rise in free fatty acid (FFA) even when stored at room temp, in open containers, for a period of three months, and a slight
rise after one year storage; and that the bran was agglomerated into large particles which eliminated the “fines” and channeling
problems characteristic of rice bran; and that the retention time for good extraction was on the order of 45 min; and that
the percolation rate for a four ft depth of expanded bran was on the order of 35 gpm/ft2. 相似文献
218.
Solid circulation patterns were determined by measuring collisions between tracer particles and cylindrical probes in liquid—solid and gas—liquid—solid fluidized beds. Special probes were used to obtain two‐ and three‐dimensional views of particle motion. Circulation patterns for 3 and 5 mm glass beads were studied. Mixing cells, which had been formed at low liquid velocities, grew in size and eventually merged as the liquid velocity increased. The flow patterns of smaller particles having the same density as bed particles and particles lighter than bed particles (graphite particles) with the same size were also measured. 相似文献
219.
Inculet Ion I. Bergougnou Maurice A. Bauer Stanley 《Industry Applications, IEEE Transactions on》1972,(6):744-748
The paper presents a new apparatus for electrostatic beneficiation of fluidized ores. The apparatus comprises a fluidized bed, an optional metallic screen electrode located above the bed, and a series of collecting U-or V-shaped troughs. The troughs are moving horizontally below the screen. The vertical electric field traversing the fluid bed was produced by applying high voltage to a porous metallic plate on the floor of the bed and grounding the troughs and screen. 相似文献
220.
Nicolas Frémy Vincent Maurice Philippe Marcus 《Journal of the American Ceramic Society》2003,86(4):669-75
The initial stages of growth of ordered layers of Al2 O3 on NiAl(001) single-crystal surfaces at 1025 K and 10−7 mbar (10−5 Pa) in O2 have been studied using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). The STM results evidence the formation of elongated strips (26 Å wide and 11 Å high) of Al2 O3 oriented along the [100] and [010] directions of the substrate. With longer oxidation, the substrate is increasingly covered by rectangular and striped islands resulting from the vicinal and parallel growth of the strips. On the ultrathin oxide film formed after 500 L (1 L = 10−6 torr·s (∼1.33 × 10−4 Pa·s)) of exposure, STM atomic resolution images have been obtained for the first time. They evidence the [001] orientation of the oxygen sublattice in Bain epitaxy on the substrate. The observation of one-dimensional atomic trenches together with the strips observed on the nanometer scale is consistent with the growth of θ-Al2 O3 . The STS local measurements evidence the insulating behavior of the oxide layer formed with a gap value ranging from 7 and 8 eV for amorphous and ordered domains, respectively. 相似文献