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71.
A general model is proposed to optimize the shading interaction between an awning and an external wall that project shadows on the facade of a construction. The original method was presented by the authors in Renewable Energy 28 (2003): 111, for a particular shading proposal. They emphasize the advantage of a one-dimensional approach to solve the problem of this interaction, analyzing the shadows projected by these elements from a side view. The generalized method, presented in this paper, is useful for architects to design shelter projects with more alternatives in the use of such shading devices. The general model also permits study and evaluation of any strategy chosen by the builder to shadow a facade, with an emphasis on windowpane shading, through graphical outputs of the solar performance. 相似文献
72.
This paper describes a new algorithm for visual control of an uncalibrated 3 DOF joint system, using two weakly calibrated fixed cameras. The algorithm estimates on-line the Image Jacobian, a matrix which linearly relates joint velocity and image feature velocity. In our experiments we prove that by using the fundamental matrix, robustness of the estimation in the presence of noise is significantly increased with respect to already existing algorithms in specialized literature. 相似文献
73.
74.
This paper deals with the scheduling of operations on a multiprocessor machine in the context of shoe manufacturing. Multiprocessor machines are composed of several parallel processors. Unlike parallel machines, the entire machine needs to be stopped whenever a single processor needs a setup. Our industrial partner, one of the major winter-shoe manufacturers in Canada, offers a relatively large variety of models. For each of these models, all the sizes proposed by this manufacturer must be produced in various quantities. Our objective is to schedule the production of the required sizes on the machine's different processors in order to minimize the global makespan, which includes both the production time and the set up time. We first present a mathematical formulation of the problem. Then, we introduce a decomposition procedure based on the mathematical model, and we demonstrate that this procedure is very efficient for small- and medium-size instances. We also propose two construction heuristics and two improvement heuristics for larger problems, and we report the results of our extensive computational experiments to demonstrate the quality of the proposed heuristics in terms of reducing production time and computational effort. 相似文献
75.
Angel Kuri-Morales Fátima Rodríguez-Erazo 《Engineering Applications of Artificial Intelligence》2009,22(1):57-65
Given the present need for Customer Relationship and the increased growth of the size of databases, many new approaches to large database clustering and processing have been attempted. In this work, we propose a methodology based on the idea that statistically proven search space reduction is possible in practice. Two clustering models are generated: one corresponding to the full data set and another pertaining to the sampled data set. The resulting empirical distributions were mathematically tested to verify a tight non-linear significant approximation. 相似文献
76.
D. Iordachescu M. Iordachescu B. Georgescu R.M. Miranda J. Ruiz-Hervias J.L. Ocaña 《Journal of Materials Processing Technology》2010,210(6-7):951-960
This paper presents the performances of an original longitudinal magnetization system, designed to assure the magnetic flux concentration on the tube wall. This magnetization system is made of several small peripheral solenoids disposed around each tube, parallel to the tube axis, and was used to investigate the interaction between the arc and the magnetic field in case of MIAB (Magnetically Impelled Arc Butt) welding of low carbon steel thin-walled tubes. The main research objective was the development of process parametrical windows for assuring qualitative joint achievement. Macro- and micro-structural analysis accompanies the hardness tests made on corresponding welded samples, demonstrating the operational process maps in producing sound MIAB joints. The paper also discusses the process main stages based on corresponding images resulting from process monitoring, from arc initiation to the emergence of molten metal when upsetting starts and the weld is formed. 相似文献
77.
Commercial refrigerated or frozen flatfish fillets are sometimes mislabeled, and identification of these mislabeled products is necessary to prevent fraudulent substitution. Identification of nine commercial flatfish species (order Pleuronectiformes), Hippoglossus hippoglossus (halibut), Lepidorhombus boscii (four-spotted scaldfish), Lepidorhombus whiffiagonis (megrin), Platichthys flesus (flounder), Pleuronectes platessa (European plaice), Reinhardtius hippoglossoides (Greenland halibut), Scophthalmus maximus (turbot), Scophthalmus rhombus (brill), and Solea vulgaris (=Solea solea) (sole), was carried out on the basis of the amplification of a 486-bp segment of the mitochondrial genome (tRNA(Glu)/cytochrome b) by using the polymerase chain reaction (PCR) and universal primers. Sequences of PCR-amplified DNA from the flatfish species were used to select eight restriction enzymes (REs). The PCR products were cut with each RE, resulting in species-specific restriction fragment length polymorphism. Seven species groups could be identified by application of the single RE DdeI and six species groups by using HaeIII, HinfI, MaeI, or MboI. Different combinations of only a couple of these REs could unambiguously identify the nine flatfish species. Genetic polymorphisms of the target sequence were examined by comparison with previously published DNA sequences, and the results of this comparison confirmed the usefulness of this technique in distinguishing and genetically characterizing refrigerated or frozen pieces of these nine flatfish species. 相似文献
78.
Luciano Boquete Rafael Barea Ricardo García Manuel Mazo M. Angel Sotelo 《Autonomous Robots》2005,18(1):5-20
This paper describes an adaptive neural control system for governing the movements of a robotic wheelchair. It presents a new model of recurrent neural network based on a RBF architecture and combining in its architecture local recurrence and synaptic connections with FIR filters. This model is used in two different control architectures to command the movements of a robotic wheelchair. The training equations and the stability conditions of the control system are obtained. Practical tests show that the results achieved using the proposed method are better than those obtained using PID controllers or other recurrent neural networks models 相似文献
79.
80.
A study was made of the diurnal changes in liver microsomal desaturation of labeled stearic, linoleic and α-linolenic acids
to oleic, γ-linolenic and octadeca-6,9,12,15-tetraenoic acids, respectively. C3H-S mice were used and were exposed to light-dark
cycles. A circadian rhythm was observed for stearic acid desaturation, and a different one for linoleic acid. Linoleic and
α-linolenic desaturation had similar responses in the day cycle. This would indicate that different mechanisms control the
oxidative desaturations of the fatty acids in the 9 and 6 carbons. The fatty acid composition of the whole liver and liver
microsomes also showed variations. Remarkable oscillations were observed for stearic and oleic acids. Neither the total protein
synthesis nor the free fatty acid concentration in the microsomes followed a rhythm parallel to the desaturation of the studied
fatty acids. The injection of cycloheximide 4 hr before measuring the desaturation modified the circadian variation of both
the 9 and 6 desaturations. The modification induced by cycloheximide was considered to indicate that both variations are related
to the synthesis of specific proteins but not to that of a degradative or inhibitory protein. 相似文献