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1.
2.
Galli R. Tenca A.F. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2004,12(1):52-66
The use of online arithmetic was often proposed for hardware implementations of complex digital-signal processing (DSP) algorithms. However, several important issues in the design process of such algorithms using online arithmetic are rarely discussed in the literature. This paper presents these issues and provides a methodology to analyze the behavior of networks of online arithmetic modules performing serial computation over fixed-point numbers. The methodology is presented, applied in several examples, and finally used to design an efficient field programmable gate arrays implementation of the Levinson-Durbin algorithm in an application of the Yule-Walker power spectrum estimation. The methodology can be applied to other algorithms as well and it simplifies the task of designing and verifying a network of online modules. The experimental results show the advantages of online arithmetic in the design of complex DSP algorithms. 相似文献
3.
Alvaro E. Gil Author Vitae Author Vitae 《Automatica》2006,42(2):245-250
Resource allocation involves deciding how to divide a resource of limited availability among multiple demands in a way that optimizes current objectives. In this brief paper we focus on one type of distributed resource allocation problem where via an imperfect communication network multiple processors can share the load presented by multiple task types. We introduce asynchronous “cooperative” resource allocation strategies, and show that they lead to a bounded cumulative demand. 相似文献
4.
5.
Examined the relationship between aphasia type and lesion site in 80 subcortical stroke patients. Ss were classified as affected by aphasia, dysarthria, and nonaphasia, nondysarthria. Sites of lesions were identified by means of computerized tomography (CT) scan. No correlation between site of lesions and category group was found. Lesions of the same subcortical structures yielded different neurolinguistic impairment, whereas comparable linguistic patterns were observed with lesions of different deep areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Alvaro Realpe 《Powder Technology》2006,169(2):108-113
A large part of pharmaceutical manufacturing involves the use of particulate materials. It is well known that both particle size and shape affect the physical characteristics of tablets. An image processing and analysis algorithm based on the invariant image moment technique was developed in this work to determine the particle shape by comparing features (moments) extracted from templates to those extracted from each of the objects in the image. First it determines the particle shape (rectangle, circle, etc.) and then calculates its specific dimensions (diameter, aspect ratio).The statistical validation of the vision system obtained a repeatability of 0.0012 in and 0.5% relative standard deviation and accuracy within 0.1 to 0.9% of the average value considered as true value. Also the pattern recognition technique indicated high precision and accuracy for images containing particles with some level of contact between them. The shape recognition of microcrystalline cellulose (MCC) indicated that particles of equant and acicular shape as defined by USP are predominant. The results suggest that image processing and analysis would be a suitable tool for pharmaceutical process analytical technologies (PAT) and process optimization. 相似文献
7.
Juan Chirinos Jose Arévalo Tamara Rajmankina Angel Morillo Darmenia Ibarra Ali Bahsas Alvaro Parada 《Polymer Bulletin》2004,51(5-6):381-387
Summary The complex
5-(C5H5)2Ti
(1-OC(O)C6H5)2
was synthesized and activated with MA0 for ethylene
polymerization. The resultant polymer is UHMW-PE with a
viscosimetric molecular weight of Mv = 6.8 x
106 to 0.7 x
106 g/mol dependent on the
temperature of the reaction. The effects of the Al/Ti molar
ratio and temperature of the reaction on the catalytic activity
and polymer properties were studied. 相似文献
8.
Alvaro Chacon 《新世纪水泥导报》2007,13(Z1):45-47
随着能源成本的增加,水泥行业不断寻求利用石油焦炭等替代燃料,但这些替代燃料的使用增加了物料在预热器、窑、冷却机中的阻塞和堆积。对物料的堵塞和堆积,常用的清除方法会带来许多弊端。利用空气炮防止物料的阻塞和堆积比较有效,可以从熟料质量、熟料产量、耐火材料寿命、能源、安全性等方面达到降低成本的目的。马丁公司在预热器和冷却器的改造方面与水泥行业有非常紧密的合作,墨西哥水泥厂是这种合作关系成功的典范。从1996年至今,墨西哥水泥厂已经安装了大约2900个马丁公司的BIG BLASTER空气炮,每年因为安装空气炮带来的收益达27万美元。基于此,UCC万吨熟料生产线也不例外地选用于马丁公司的空气炮。 相似文献
9.
Josianne Lefebvre Federico Galli Claudia L. Bianchi Gregory S. Patience Daria C. Boffito 《加拿大化工杂志》2019,97(10):2588-2593
X‐ray photoelectron spectroscopy (XPS) is a quantitative surface analysis technique used to identify the elemental composition, empirical formula, chemical state, and electronic state of an element. The kinetic energy of the electrons escaping from the material surface irradiated by an x‐ray beam produces a spectrum. XPS identifies chemical species and quantifies their content and the interactions between surface species. It is minimally destructive and is sensitive to a depth between 1–10nm. The elemental sensitivity is in the order of 0.1 atomic %. It requires ultra high vacuum ( Pa) in the analysis chamber and measurement time varies from minutes to hours per sample depending on the analyte. XPS dates back 50 years ago. New spectrometers, detectors, and variable size photon beams, reduce analysis time and increase spatial resolution. An XPS bibliometric map of the 10 000 articles indexed by Web of Science[1] identifies five research clusters: (i) nanoparticles, thin films, and surfaces; (ii) catalysis, oxidation, reduction, stability, and oxides; (iii) nanocomposites, graphene, graphite, and electro‐chemistry; (iv) photocatalysis, water, visible light, and ; and (v) adsorption, aqueous solutions, and waste water. 相似文献
10.
So far, most of the applications of robotic technology to education have mainly focused on supporting the teaching of subjects
that are closely related to the Robotics field, such as robot programming, robot construction, or mechatronics. Moreover,
most of the applications have used the robot as an end or a passive tool of the learning activity, where the robot has been
constructed or programmed. In this paper, we present a novel application of robotic technologies to education, where we use
the real world situatedness of a robot to teach non-robotic related subjects, such as math and physics. Furthermore, we also
provide the robot with a suitable degree of autonomy to actively guide and mediate in the development of the educational activity.
We present our approach as an educational framework based on a collaborative and constructivist learning environment, where
the robot is able to act as an interaction mediator capable of managing the interactions occurring among the working students.
We illustrate the use of this framework by a 4-step methodology that is used to implement two educational activities. These
activities were tested at local schools with encouraging results. Accordingly, the main contributions of this work are: i) A
novel use of a mobile robot to illustrate and teach relevant concepts and properties of the real world; ii) A novel use of
robots as mediators that autonomously guide an educational activity using a collaborative and constructivist learning approach;
iii) The implementation and testing of these ideas in a real scenario, working with students at local schools.
相似文献
Alvaro Soto (Corresponding author)Email: |