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排序方式: 共有459条查询结果,搜索用时 15 毫秒
31.
Carlos A. Montoya Jean-Paul Lallès Stephen Beebe Pascal Leterme 《Food research international (Ottawa, Ont.)》2010,43(2):443-449
This article proposes a new way to improve the protein quality of the common bean (Phaseolus vulgaris). It is based on the natural variability found in the different types of phaseolin, its main storage protein (40–50% of the total protein). Despite the fact that it is deficient in methionine content, phaseolin still represents the main source of that amino acid in the seed. More than 40 genetic variants, differing in subunit number (2–6) and molecular weight (40–54 kDa) have been analyzed. The similarity of the amino acid composition among phaseolins, suggests that a nutritional improvement cannot be expected from that side. Conversely, important variation in phaseolin susceptibility to proteolysis (ranging from 57% to 96% after cooking) has been observed, increasing the theoretical availability of methionine by up to 37%. Therefore, breeding programs based on highly-digestible phaseolin types could lead to the production of beans with higher protein quality. 相似文献
32.
Kouamé D Girault JM Remenieras JP Chemla JP Lethiecq M 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(3):267-278
For pt.I see ibid., vol.50, no.3, p.267-78 (2003). This paper presents an application of continuous wave ultrasound Doppler velocity measurements to two-phase flow in pipes. In many petroleum wells, the multiphase flow is separated into two phases: the first is a liquid phase and the second is a gas phase with small scatterers. The problem of multiphase velocity profile measurements has not been satisfactorily solved by classical approaches due to the multiphase nature of the fluid and the presence of colored noise, which introduces a significant bias in classical frequency estimators. We propose the use of resolution frequency techniques to overcome the classical limitations. Direct estimation of Doppler frequency then obtained using either time frequency maximum frequency or arguments of poles of the parametric model that identifies the Doppler part of the signal is discussed. The tests made with synthetic Doppler signals and two-phase flow have demonstrated the excellent performance of the high resolution techniques based on reassignment and parametric techniques. 相似文献
33.
In this paper we recall general methodologies we developed for observation and identification in non-linear systems theory, and we show how they can be applied to real practical problems. In a previous paper, we introduced a filter which is intermediate between the extended Kalman filter in its standard version and its high-gain version, and we applied it to certain observation problems. But we were missing some important cases. Here, we show how to treat these cases. We also apply the same technique in the context of our identifiability theory. As non-academic illustrations, we treat a problem of observation and a problem of identification, for a fluid catalytic cracker (FCC). This FCC unit is one of the most crucial from an economic point of view for the petroleum industry. 相似文献
34.
功率因数校正(PFC)电路嵌在交流线路与主电源之间,从交流线路汲入正弦电流,从而提供恒定直流电压。这中间段一般是升压转换器,电感是系统中体积最大且昂贵的元器件之一。在对成本和尺寸敏感的应用中,必须将电感的尺寸和成本降至最低。 相似文献
35.
The purpose of this paper is to present inverse optimal control as a promising approach to transfer biological motions to
robots. Inverse optimal control helps (a) to understand and identify the underlying optimality criteria of biological motions
based on measurements, and (b) to establish optimal control models that can be used to control robot motion. The aim of inverse
optimal control problems is to determine—for a given dynamic process and an observed solution—the optimization criterion that
has produced the solution. Inverse optimal control problems are difficult from a mathematical point of view, since they require
to solve a parameter identification problem inside an optimal control problem. We propose a pragmatic new bilevel approach
to solve inverse optimal control problems which rests on two pillars: an efficient direct multiple shooting technique to handle
optimal control problems, and a state-of-the art derivative free trust region optimization technique to guarantee a match
between optimal control problem solution and measurements. In this paper, we apply inverse optimal control to establish a
model of human overall locomotion path generation to given target positions and orientations, based on newly collected motion
capture data. It is shown how the optimal control model can be implemented on the humanoid robot HRP-2 and thus enable it
to autonomously generate natural locomotion paths. 相似文献
36.
37.
通过与其它传感技术的对比,简要分析了激光视觉在焊接生产中得到成功应用的原因。分析了早期激光视觉系统的特征和当时面临的挑战。介绍了Servo-Robot激光视觉的关键技术和已取得的显著进步,阐述了集成激光视觉的移动式便携焊接机器人和激光视觉在焊缝质量检测中的应用。展望了激光视觉系统的未来和智能视觉在提高机器人性能方面发展的显著进步,包括改进机器人人工示教、离线编程及视觉辅助机器人示教。 相似文献
38.
39.
Michèle Marcotte Cuiren R. Chen Stefan Grabowski Hosahalli S. Ramaswamy & Jean-Paul Gabriel Piette 《International Journal of Food Science & Technology》2008,43(4):673-684
Traditional cooking‐cooling of processed meat and poultry products is industrially carried out in smokehouses or autoclaves. A mathematical model was developed to simulate these operations. Equations, describing heat transfer and thermal destruction of micro‐organisms and quality characteristics, were solved numerically. The model was validated experimentally for heat transfer and energy consumption and was used to perform a sensitivity analysis. Input variables were: process time (PT), smokehouse temperature (TSH), bologna size (diameter, D and height, H), surface heat transfer coefficients (hheat and hcool), product thermal diffusivity (αheat and αcool). Output variables were: product core temperature (Tc), core and volume‐average lethality (Pcm and Pvm) and cook (Cc and Cv) values as well as surface (Qs) and volume‐average (Qv) quality retention, total specific energy consumption (En) and energy efficiency (Ce). Multiple linear regression models were developed to predict Cc and Cv from five inputs and used to obtain acceptable deviation ranges. 相似文献
40.
Jean-Paul Mazellier Olivier Faynot Sorin Cristoloveanu Simon Deleonibus Philippe Bergonzo 《Diamond and Related Materials》2008,17(7-10):1248-1251
We examine here by electro-thermal simulation tools (SILVACO's Atlas) a configuration of Silicon-On-Insulator substrate for Fully-Depleted MOSFET architectures, incorporating diamond as buried insulator, and compare it with traditional silicon dioxide BOX for the future technological nodes of the ITRS (90 nm and below). Our aim is to give major trends to be followed in order to optimize diamond integration from electrical and thermal points of view, constraints that must be kept in mind in parallel with the technological work on thin diamond films. In this theoretical study, we perform a benchmarking between SiO2 and diamond BOX. We first point out that the BOX thickness should not be more than few hundred nanometers to maintain electrical performances. From thermal point of view, we demonstrate that the replacement of 100 nm thick buried oxide by a 100 nm thick diamond layer can lead to about 50% reduction of the temperature when only 33% decrease can be obtained with Ultra Thin SiO2 BOX (20 nm). Furthermore, thick diamond BOX avoids the parasitic capacitances issue that reduces Ultra Thin BOX devices working frequency. 相似文献