The matrix properties of minimum-time discrete linear regulator control

Although the abrasive reinforcement in MMCs primarily controls their machining behavior, the properties of the matrix also exert an influence. A 1200 W diode laser was used, due to the large footprint (5×0.3 mm) and the short wavelength (0.94 μm) to pre-treat a 2618 (18% SiC) alloy. The laser heating and self-quenching of the material modified the matrix properties. Machining performance was then assessed by measuring tool wear and edge condition, cutting forces, surface finish, and sub-surface damage. Results indicated that pre-treatment gave less wear, lower forces, and less sub-surface damage although abrasion remained the primary wear mechanism.

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Cyanate Ester Resin/Silica subnanocomposites and their superiority over nanocomposites due to fundamental role of constrained interfacial dynamics

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012100 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012100

Author(s):

V A Bershtein ◽

A M Fainleib ◽

D A Kirilenko ◽

P N Yakushev

Keyword(s):

Positive Impact ◽

Sol Gel ◽

Cyanate Ester ◽

Interfacial Dynamics ◽

Cyanate Ester Resin ◽

Sol Gel Process ◽

Matrix Properties ◽

Interfacial Areas ◽

The Matrix

Abstract The study of nanostructure, thermal and relaxation properties (by HAADF-STEM, EDXS, DMA and DSC), combined with the calculations of interparticle distances and interfacial areas, has been performed for a series of the hybrid Cyanate Ester Resin (CER)/Si02 polymer composites with 0.01 to 10 wt.% Si02 units introduced via a sol-gel process. The absence of clusterization, arising only subnanometric Si02 nodes and their quasi-regular distribution within the amorphous matrix, with the shortest distances between nodes, provided their exceptional positive impact on the matrix properties at ultra-low Si02 contents of 0.03-0.1 wt.%. The superiority of these subnanocomposites over the nanocomposites was determined by the role of constrained interfacial dynamics over the whole matrix.

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On the theory of constructive construction of a linear controller

Vestnik of Saint Petersburg University Applied Mathematics Computer Science Control Processes ◽

10.21638/11701/spbu10.2020.309 ◽

2020 ◽

Vol 16 (3) ◽

pp. 326-344

Author(s):

Alexander M. Kamachkin ◽

◽

Nikolai A. Stepenko ◽

Gennady M. Chitrov ◽

◽

...

Keyword(s):

Classical Problem ◽

Original System ◽

Diagonal Form ◽

Linear Controller ◽

Controlled Systems ◽

Linear Regulator ◽

The Matrix ◽

Zubov’S Method ◽

Block Diagonal Form ◽

Stationary Stabilization

The classical problem of stationary stabilization with respect to the state of a linear stationary control system is investigated. Efficient, easily algorithmic methods for constructing controllers of controlled systems are considered: the method of V. I. Zubov and the method of P. Brunovsky. The most successful modifications are indicated to facilitate the construction of a linear controller. A new modification of the construction of a linear regulator is proposed using the transformation of the matrix of the original system into a block-diagonal form. This modification contains all the advantages of both V. I. Zubov’s method and P. Brunovsky’s method, and allows one to reduce the problem with multidimensional control to the problem of stabilizing a set of independent subsystems with scalar control for each subsystem.

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Effect of laser deweighting on properties of ZL205A aluminum alloy

Journal of Physics Conference Series ◽

10.1088/1742-6596/2137/1/012033 ◽

2021 ◽

Vol 2137 (1) ◽

pp. 012033

Author(s):

Guang Li ◽

Zhipeng Wei ◽

Junlong Wang ◽

Yangyang Zhang ◽

Chen Wang ◽

...

Keyword(s):

Experimental Study ◽

Surface Roughness ◽

Aluminum Alloy ◽

Surface Morphology ◽

Pulse Laser ◽

Process Parameters ◽

Experimental Results ◽

Matrix Properties ◽

Before And After ◽

The Matrix

Abstract In this paper, a nanosecond fiber pulse laser is used to carry out the experimental study on laser weight removal of ZL205A aluminum alloy gyro rotor. By optimizing the process parameters of laser weight removal, better surface morphology was obtained. The effects of surface roughness, metallographic structure and hardness of samples before and after laser deweighting were analyzed. The experimental results show that the laser weight removal does not affect the matrix properties of ZL205A aluminum alloy. The laser de-weight technology is suitable for the balance of ZL205A aluminum alloy gyro rotor.

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Can exercise modulate the maturation of functionally different immature tendons in the horse?

Journal of Applied Physiology ◽

10.1152/japplphysiol.00379.2007 ◽

2008 ◽

Vol 104 (2) ◽

pp. 416-422 ◽

Cited By ~ 9

Author(s):

Y. Kasashima ◽

T. Takahashi ◽

H. L. Birch ◽

R. K. W. Smith ◽

A. E. Goodship

Keyword(s):

Mechanical Properties ◽

Athletic Training ◽

High Frequency ◽

Matrix Protein ◽

High Strain ◽

Exercise Program ◽

Functional Adaptation ◽

Matrix Properties ◽

The Matrix ◽

Young Horses

Tendons can be considered in two functional groups, those contributing to energetics of locomotion and those acting solely to position the limb. The energy-storing tendons in both human and equine athletes have a high frequency of injury with similar pathophysiology. In previous studies, high-intensity exercise appears to induce a disruption of the matrix rather than functional adaptation in adults. Here we explore the hypothesis that the introduction of controlled exercise during growth would result in an adaptive response without deleterious effects. Young horses were given a controlled exercise program similar to that previously shown to induce matrix changes in energy-storing tendons of skeletally mature animals. The tendons were assessed in relation to mechanical properties, molecular composition, and morphology. Results showed a significant increase in cartilage oligomeric matrix protein (COMP) in the positional tendon but not in the energy-storing tendon. Other matrix properties and mechanical properties were not significantly changed. While the imposition of high-strain-rate exercise in immature horses failed to augment the development of the energy-storing tendon over and above that induced by normal pasture exercise, it did not induce deleterious changes, supporting an earlier introduction of athletic training in horses.

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Effects of preparation methods on the mechanical and thermal properties of graphene-modified HNBR composites

e-Polymers ◽

10.1515/epoly-2017-0074 ◽

2018 ◽

Vol 18 (1) ◽

pp. 57-65 ◽

Cited By ~ 1

Author(s):

Dejiang Yang ◽

Chun Wei ◽

Yongyang Gong ◽

Tianxi Liu ◽

Jian Lv

Keyword(s):

Mechanical And Thermal Properties ◽

Butadiene Rubber ◽

Mechanical Mixing ◽

Graphene Nanosheet ◽

Preparation Methods ◽

Reinforcing Effect ◽

Final Performance ◽

Matrix Properties ◽

The Matrix ◽

Mixing Method

AbstractPolymers modified by graphene have become an attractive method to enhance the matrix properties, wherein the dispersion of graphene in the matrix and the interfacial interactions between graphene and matrix are critical to influence the final performance. In the present work, graphene nanosheet (GNS)-modified hydrogenated nitrile butadiene rubber (GNS/HNBR) composites were prepared via solution-mixing and mechanical-blending methods. The curing performance, mechanical properties and heat resistance of the prepared composites were studied. The results showed that when the content was 0.2 wt%, the tensile strength and modulus at 300% elongation of the GNS/HNBR composite prepared via solution-mixing method reached 19.36 and 3.62 MPa, which increased by 32% and 18% compared with those of pure HNBR, respectively. In addition, the swelling index of the composite in cyclohexane was decreased from 413% to 337%. On the other hand, the tensile property of GNS/HNBR composite prepared by mechanical-mixing method became poor. SEM observation showed that GNS was well dispersed and incorporated into HNBR via the solution-mixing method, resulting in a significant reinforcing effect.

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Rheological Study of Composite Materials Based on Thermosetting Matrix and Fillers Mineral

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.550.79 ◽

2013 ◽

Vol 550 ◽

pp. 79-84

Author(s):

Amar Irekti ◽

B. Bezzazi

Keyword(s):

Shear Stress ◽

Composite Materials ◽

Rheological Behavior ◽

Rheological Parameters ◽

Mineral Filler ◽

Composites Materials ◽

Matrix Properties ◽

The Matrix ◽

The Cost ◽

Mineral Fillers

In the development of composites materials, the matrix acts as a binder of different reinforcements can distribute the stress, provide good resistance to chemical structure and the desired shape to the final product. But there are still some drawbacks that arise in the physicochemical and mechanical properties of thermosetting matrices. Our job is to synthesize composite materials with news formulations of thermosetting matrices (Granitex products) by the incorporation of 40% of local mineral fillers. The latter give the matrix properties which it does not have, first, to reduce the cost of composite materials, and secondly, to improve implementation by increasing the viscosity and reducing the withdrawal to its minimum value. Rheological testing of mixtures prepared is made on the cone-plate viscometer, or the sample undergoes a shear in the conical space between the plane and the cone. The geometry of the cone - package ensures constant velocity gradient throughout the volume. The rheograms obtained, represents the evolution of the shear stress as a function of shear rate of resin mixtures containing 35% of mineral filler (pozzolan). The mineral filler increases significantly in rheological parameters, whatever the nature of the mineral filler. Compared to the control without charges, an increase of 60% of the shear stress and that of plastic viscosity were recorded for the epoxy resin. The software Rheowine viscometer, enabled us to model and identified the rheological behavior of these mixed with resin. The results obtained in this modeling, confirmed that the resin mixtures have shear-thinning rheological behavior and their behavior follows the model of the Ostwald of Waele.

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Advanced thermoplastics and their composites

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1987.0064 ◽

1987 ◽

Vol 322 (1567) ◽

pp. 451-464 ◽

Cited By ~ 18

Keyword(s):

High Performance ◽

Molecular Structures ◽

Particulate Composites ◽

Structural Composites ◽

Chemical Attack ◽

Working Environments ◽

Matrix Properties ◽

The Matrix ◽

The One ◽

Fibre Matrix

Composite materials, be they highly oriented continous-fibre structural materials or short-fibre and even particulate composites, remain critically dependent upon matrix properties. Interest in the use of thermoplastic matrices has spread from conventional injection moulding composites into collimated continuous fibre materials. As the critical applications of such materials have been explored, so the demands on matrix properties have become clearer, and potentially more stringent. The demand for advanced properties is set primarily by response of the matrix, and fibre matrix interface to hostile working environments involving temperature, chemical attack, and physical abuse. Such properties are a reflection of molecular structures and their resulting morphology, but the achievement of desirable properties is bounded also by synthesis on the one hand and component fabrication on the other. By definition, such highly engineered materials and their related processes must exhibit ‘reliability’. The paper attempts to relate the interaction between structure and properties for such materials concentrating on high-performance structural composites and a view of the broad requirements if such materials are to have use.

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