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71.
Pablo Cortés Luis Onieva Jesús Muñuzuri José Guadix 《Computers & Industrial Engineering》2013,64(1):403-411
Nowadays is very common the presence of tall buildings in the business centres of the main cities of the world. Such buildings require the installation of numerous lifts that are coordinated and managed under a unique control system. Population working in the buildings follows a similar traffic pattern generating situations of traffic congestion. The problem arises when a passenger makes a hall call wishing to travel to another floor of the building. The dispatching of the most suitable car is the optimization problem we are tackling in this paper. We develop a viral system algorithm which is based on a bio-inspired virus infection analogy to deal with it. The viral system algorithm is compared to genetic algorithms, and tabu search approaches that have proven efficiency in the vertical transportation literature. The experiments undertaken in tall buildings from 10 to 24 floors, and several car configurations from 2 to 6 cars, provide valuable results and show how viral system outperforms such soft computing algorithms. 相似文献
72.
73.
Proteases occupy the most relevant position among industrial enzymes. Plant proteases have been used in medicine, detergent manufacturing, and food science for many years, but their production is diminishing in favor of those of microbial origin because lower production costs. Papain, bromelain, and ficin are the most frequently employed plant proteases, although new proteases with new and more appealing physicochemical properties for industry are still emerging. DNA technology and genetic engineering shall play, without a doubt, an important role for the production of these proteases at the industrial level. The present review focuses on the applications of traditional plant proteases as well as new proteases discovered during the last 20 years, some of which have already been genetically engineered either to increase production or to strengthen some of their physicochemical properties. The review also refers to the protease classification, action pattern, and main characteristics. 相似文献
74.
José R. Sendra Javier del Pino Antonio Hernández Benito González Javier García Andrés García-Alonso Antonio Nunez 《Analog Integrated Circuits and Signal Processing》2003,35(2-3):121-132
In this work we propose a modification to the conventional lumped equivalent circuit model for integrated inductors. Also the widely used parametric model is modified. The proposed models expand the frequency range where the integrated inductor behavior is accurately predicted. They are useful in developing automatic tools to assist the designers in selecting and automatically laying-out integrated inductors [1]. This work is based on measurements from integrated inductors fabricated in a standard silicon process. 相似文献
75.
Eva Pellicer Moisés Cabo Emma Rossinyol Pau Solsona Santiago Suriñach Maria Dolors Baró Jordi Sort 《Advanced functional materials》2013,23(7):900-911
Transition metal (Co, Fe, Mn)‐doped In2O3?y mesoporous oxides are synthesized by nanocasting using mesoporous silica as hard templates. 3D ordered mesoporous replicas are obtained after silica removal in the case of the In‐Co and In‐Fe oxide powders. During the conversion of metal nitrates into the target mixed oxides, Co, Fe, and Mn ions enter the lattice of the In2O3 bixbyite phase via isovalent or heterovalent cation substitution, leading to a reduction in the cell parameter. In turn, non‐negligible amounts of oxygen vacancies are also present, as evidenced from Rietveld refinements of the X‐ray diffraction patterns. In addition to (In1?xTMx)2O3?y, minor amounts of Co3O4, α‐Fe2O3, and MnxOy phases are also detected, which originate from the remaining TM cations not forming part of the bixbyite lattice. The resulting TM‐doped In2O3?y mesoporous materials show a ferromagnetic response at room temperature, superimposed on a paramagnetic background. Conversely, undoped In2O3?y exhibits a mixed diamagnetic‐ferromagnetic behavior with much smaller magnetization. The influence of the oxygen vacancies and the doping elements on the magnetic properties of these materials is discussed. Due to their 3D mesostructural geometrical arrangement and their room‐temperature ferromagnetic behavior, mesoporous oxide‐diluted magnetic semiconductors may become smart materials for the implementation of advanced components in spintronic nanodevices. 相似文献
76.
77.
El Mostapha Aboulhamid Younès Karkouri Eduard Cerny 《Journal of Electronic Testing》1993,4(3):237-253
This article presents a new method to generate test patterns for multiple stuck-at faults in combinational circuits. We assume the presence of all multiple faults of all multiplicities and we do not resort to their explicit enumeration: the target fault is a single component of possibly several multiple faults. New line and gate models are introduced to handle multiple fault effect propagation through the circuits. The method tries to generate test conditions that propagate the effect of the target fault to primary outputs. When these conditions are fulfilled, the input vector is a test for the target fault and it is guaranteed that all multiple faults of all multiplicities containing the target fault as component are also detected. The method uses similar techniques to those in FAN and SOCRATES algorithms to guide the search part of the algorithm, and includes several new heuristics to enhance the performance and fault detection capability. Experiments performed on the ISCAS'85 benchmark circuits show that test sets for multiple faults can be generated with high fault coverage and a reasonable increase in cost over test generation for single stuck-at faults. 相似文献
78.
Beatriz Marcotegui Ferran MarquÉs Joseph Ramon Morros Montse PardÀs Philippe Salembier 《电信纪事》1997,52(7-8):380-387
This paper deals with the relation between segmentation for coding and rate control. The efficiency of a segmentation-based coding scheme heavily relies on this step that defines how many and which regions have to be segmented. In this paper, we show that this problem can be formulated as a rate/distortion problem. The proposed solution not only controls the segmentation, but also defines the coding strategy to be used in each region. Together with the general approach, several simplified versions of the segmentation control are proposed and discussed. 相似文献
79.
Ronan Hinchet Sangmin Lee Gustavo Ardila Laurent Montès Mireille Mouis Zhong Lin Wang 《Advanced functional materials》2014,24(7):971-977
The integrated nanogenerator (NG) based on vertical nanowire (NW) arrays is one of the dominant designs developed to harvest mechanical energy using piezoelectric nanostructures. Finite element method (FEM) simulations of such a NG are developed using ZnO NWs in compression mode to evaluate its performances in term of piezoelectric potential generated, capacitance, induced mechanical energy, output electrical energy, and efficiency. This evaluation is essential to correctly understand NG operation. Three main issues are highlighted. The mechanical and electrical structures of the NG as an integrated system are optimized, and strategies for concentrating the mechanical strain field in the NWs and increasing the force sensitivity are developed. In addition, the influence of NWs length and diameter on NG performances is investigated. The optimization results in a piezoelectric nano composite material where global performances are improved by mean of long and thin NWs. 相似文献
80.
Clara Guglieri Eva Céspedes Ana Espinosa María Ángeles Laguna‐Marco Noemi Carmona Yukiharu Takeda Tetsuo Okane Tetsuya Nakamura Mar García‐Hernández Miguel Ángel García Jesús Chaboy 《Advanced functional materials》2014,24(14):2094-2100
Discoveries of room‐temperature ferromagnetism (RTFM) in semiconductors hold great promise in future spintronics technologies. Unfortunately, this ferromagnetism remains poorly understood and the debate concerning the nature, carrier‐mediated versus defect‐mediated, of this ferromagnetism in semiconducting oxides is still open. Here, by using X‐ray absorption (XAS) and X‐ray magnetic circular dichroism (XMCD), it is demonstrated that the oxygen ions have a ferromagnetic response in different ZnO‐based compounds showing RTFM behavior: ZnO nanoparticles capped with organic molecules and ZnO/ZnS heterostructures. These results demonstrate the intrinsic occurrence of RTFM in these systems, and point out that it is not related to the metallic cation but it relays on the conduction band of the semiconductor. 相似文献