The base matrix of hermitian operator order n<4

At this article we give a brief review about the additives effects for cast polyamide 6engineering plastics. The natural grade Magnesium catalyzed polyamide 6 has unique mechanicalproperties. Our target is to keep the mechanical and tribological properties with the development ofantistatic and ESD composite version. High conductive very effective to improve the electricalconductivity of magnezium catalized cast PA 6. Only few amount, 0,5% can result good antistaticproperty for the base matrix. Over 3% of additive the surface resistance of the material – performing107 Ω - can reach the ESD (Electrostatic Dissipative) category.

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Physical, mechanical properties and wear resistance of iron-base matrix materials for sintered diamond tools fabricated by HP and SPS

Mechanik ◽

10.17814/mechanik.2018.10.140 ◽

2018 ◽

Vol 91 (10) ◽

pp. 846-849

Author(s):

Elżbieta Bączek

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Metal Matrix ◽

Physical And Mechanical Properties ◽

Full Density ◽

Matrix Composites ◽

Plasma Sintering ◽

Base Matrix ◽

Spark Plasma ◽

Sintered Diamond

Metal matrix composites were prepared by hot pressing (HP) and spark plasma sintering (SPS) techniques. Ball-milled ironbase powders were consolidated to near full density by these methods at 900°C. The physical and mechanical properties of the resulting composites were investigated. The specimens were tested for resistance to both 3-body and 2-body abrasion. The composites obtained by HP method (at 900°C/35 MPa) had higher density, hardness and resistance to abrasion than those obtained by SPS method.

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A Fuzzy Control Heuristic Applied to Non-linear Dynamic System Using a Fuzzy Knowledge Representation

International Journal of Computers Communications & Control ◽

10.15837/ijccc.2010.5.2222 ◽

2010 ◽

Vol 5 (5) ◽

pp. 664 ◽

Cited By ~ 4

Author(s):

Felisa M. Cordova ◽

Guillermo Leyton

Keyword(s):

Knowledge Representation ◽

Fuzzy Control ◽

Dynamic Systems ◽

Nonlinear Dynamic ◽

Nonlinear Dynamic Systems ◽

System State ◽

Specific Level ◽

Base Matrix ◽

Different Levels ◽

Fuzzy Knowledge

This paper presents the design of a fuzzy control heuristic that can be applied for modeling nonlinear dynamic systems using a fuzzy knowledge representation. Nonlinear dynamic systems have been modeled traditionally on the basis of connections between the subsystems that compose it. Nevertheless, this model design does not consider some of the following problems: existing dynamics between the subsystems; order and priority of the connection between subsystems; degrees of influence or causality between subsystems; particular state of each subsystem and state of the system on the basis of the combination of the diverse states of the subsystems; positive or negative influences between subsystems. In this context, the main objective of this proposal is to manage the whole system state by managing the state combination of the subsystems involved. In the proposed design the diverse states of subsystems at different levels are represented by a knowledge base matrix of fuzzy intervals (KBMFI). This type of structure is a fuzzy hypercube that provides facilities operations like: insert, delete, and switching. It also allows Boolean operations between different KBMFI and inferences. Each subsystem in a specific level and its connectors are characterized by factors with fuzzy attributes represented by membership functions. Existing measures the degree of influence among the different levels are obtained (negatives, positives). In addition, the system state is determined based on the combination of the statements of the subsystems (stable, oscillatory, attractor, chaos). It allows introducing the dynamic effects in the calculation of each output level. The control and search of knowledge patterns are made by means of a fuzzy control heuristic. Finally, an application to the co-ordination of the activities among different levels of the operation of an underground mine is developed and discussed.

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Pest Resistant and Low CTE MoSi2-Matrix for High Temperature Structural Applications

MRS Proceedings ◽

10.1557/proc-350-177 ◽

1994 ◽

Vol 350 ◽

Cited By ~ 8

Author(s):

M. G. Hebsur

Keyword(s):

High Temperature ◽

Low Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Matrix Composition ◽

Temperature Oxidation ◽

Accelerated Oxidation ◽

Structural Applications ◽

Base Matrix ◽

Sic Reinforcement

AbstractThe objective of this investigation was to identify a pest resistant MoSi2-base matrix composition having properties suitable for SiC reinforcement. A 30 vol.% addition of fine Si3N4 particulates to MoSi2 significantly improved the low temperature accelerated oxidation resistance and thereby eliminated pest failure. Addition of Si3N4 also improved the high temperature oxidation resistance, strength and more importantly lowered the CTE of MoSi2 such that cracking was eliminated in a hybrid composite consisting of 30 vol.% Si3N4 and 30 vol. % SCS-6 fibers.

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Consumer awareness and willingness to purchase probiotic food and beverage products: a study of Sonipat district, Haryana

British Food Journal ◽

10.1108/bfj-06-2020-0469 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Sapna Arora ◽

Krishna Prabha ◽

Vijay Singh Sharanagat ◽

Vijendra Mishra

Keyword(s):

Functional Food ◽

High Energy ◽

Content Type ◽

Face To Face ◽

Food And Beverage ◽

National Capital ◽

Base Matrix ◽

Market Opportunities ◽

Probiotic Food ◽

Willingness To Purchase

PurposeIn a developing country like India, consumers are shifting from high-energy diet to balanced nutritional diet, which enhances the metabolic, physiological, functional and health benefits of consumers. The growing self-care and health-embracing population made the probiotic sector as lucrative market for functional food manufacturers and suppliers. Therefore, an analysis is required to understand consumers’ knowledge and buying behavior regarding probiotic products for product innovation and development.Design/methodology/approachAwareness, knowledge and consumption patterns of probiotic products were investigated among randomly selected 306 consumers in the Sonipat city of Haryana, which comes in the proximity of national capital, i.e. Delhi, India. A structured questionnaire with exploratory characteristics was developed and face-to-face interviews were conducted as a part of data collection.FindingsThe inference is that there is immense potential for the probiotic fruit beverage market as a higher proportion of the population was interested in probiotic products delivered with fruits as a base matrix followed by dairy products. Further, government’s initiation and support are required not only for manufacturing such health-beneficial products having therapeutic value but also to spread awareness regarding the necessity of including such products in the meals of the growing children.Originality/valueThe study shows changing customer attitudes toward probiotic products and sheds light on consumers’ preference on the medium (food matrix) of probiotic delivery, thereby exploring market opportunities in the area of the functional food sector.

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Research of SWNMF with New Iteration Rules for Facial Feature Extraction and Recognition

Symmetry ◽

10.3390/sym11030354 ◽

2019 ◽

Vol 11 (3) ◽

pp. 354

Author(s):

Jing Zhou

Keyword(s):

Feature Extraction ◽

Matrix Factorization ◽

Nonnegative Matrix Factorization ◽

Recognition Rate ◽

Nonnegative Matrix ◽

Facial Feature ◽

Face Database ◽

Base Matrix ◽

Sparse Nonnegative Matrix Factorization ◽

Pca Method

Weighted nonnegative matrix factorization (WNMF) is a technology for feature extraction, which can extract the feature of face dataset, and then the feature can be recognized by the classifier. To improve the performance of WNMF for feature extraction, a new iteration rule is proposed in this paper. Meanwhile, the base matrix U is sparse based on the threshold, and the new method is named sparse weighted nonnegative matrix factorization (SWNMF). The new iteration rules are based on the smaller iteration steps, thus, the search is more precise, therefore, the recognition rate can be improved. In addition, the sparse method based on the threshold is adopted to update the base matrix U, which can make the extracted feature more sparse and concentrate, and then easier to recognize. The SWNMF method is applied on the ORL and JAFEE datasets, and from the experiment results we can find that the recognition rates are improved extensively based on the new iteration rules proposed in this paper. The recognition rate of new SWNMF method reached 98% for ORL face database and 100% for JAFEE face database, respectively, which are higher than the PCA method, the sparse nonnegative matrix factorization (SNMF) method, the convex non-negative matrix factorization (CNMF) method and multi-layer NMF method.

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A counterexample in the theory of Hermitian liftings

Proceedings of the Edinburgh Mathematical Society ◽

10.1017/s001309150001662x ◽

1982 ◽

Vol 25 (2) ◽

pp. 141-144 ◽

Cited By ~ 1

Author(s):

D. A. Legg

Keyword(s):

Sequence Space ◽

Hermitian Operator ◽

Compact Perturbation ◽

Orlicz Sequence Space

In [3], [8], and [2], it was shown that if is an essentially Hermitian operator on l P, 1≦ p<∞, or on Lp[0,1], 1< p<∞, then T is a compact perturbation of a Hermitian operator. In [1], this result was established for operators on Orlicz sequence space l M, where 2∉[α M,β M] (the associated interval for M). In that same paper, it was conjectured that this result does not in general hold if 2∈[α M,β M]. In this paper, we show that this conjecture is correct by exhibiting an Orlicz sequence space l M and an essentially Hermitian operator on l M which is not a compact perturbation of a Hermitian operator.

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Corrosion behavioral studies on AA7075 surface hybrid composites tailored through friction stir processing

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-11-2019-2215 ◽

2020 ◽

Vol 67 (4) ◽

pp. 345-355

Author(s):

Suganeswaran Kandasamy ◽

Parameshwaran Rathinasamy ◽

Nithyavathy Nagarajan ◽

Karthik Arumugam ◽

Rajasekar Rathanasamy ◽

...

Keyword(s):

Corrosion Rate ◽

Friction Stir Processing ◽

Hybrid Composites ◽

Film Formation ◽

Content Type ◽

Rotating Speed ◽

Friction Stir ◽

Behavioral Studies ◽

Base Matrix ◽

Sem Micrograph

Purpose This paper aims to overcome the corrosion in AA7075 by incorporating the dual-reinforcements like Al2O3 and SiC through friction stir processing (FSP). In recent days, an automotive monocoque structure undergoes corrosion because of changes in environmental conditions. Design/methodology/approach Surface hybrid composites (SHCs) of AA7075 with different weight ratios of Al2O3 and SiC were fabricated at a rotating speed of 1000 rpm, traveling speed of 56 mm/min and tool tilt angle of 2º with two passes. Surface regions were observed using optical microscopy, and the potentiodynamic corrosion test was performed under a 3.5 per cent NaCl environment at room temperature. Then, the surface morphology analysis of corroded samples and their structural properties were also investigated through scanning electron microscopy (SEM), X-ray diffraction (XRD) and electron dispersive spectroscopy (EDS). Findings Through FSP, an improved interface between the reinforced particles and the AA7075 base matrix was observed because of the severe plastic deformation. Potentiodynamic polarization tests confirmed that the AA7075 matrix with a higher concentration of Al2O3 and a lower concentration of SiC (Al2O3 – 75 per cent and SiC – 25 per cent) possesses a lower corrosion rate than other specimens. This result is because of the combined effect of stable passive film formation and the resistance produced by hard SiC particles. In addition, the formation of a stronger interface between the reinforcements and the base matrix impedes the NaCl solution attack. The SEM micrograph depicts the film crystallinity variations with an increase in Al2O3 content. Debonding between the layers was observed on increasing the SiC content in the base matrix. XRD shows the peaks of reinforcing elements that influence the corrosion behavior. These observations suggest that the AA7075 reinforced with a higher concentration of Al2O3 and a lower concentration of SiC through FSP affords a suitable solution for automotive monocoque applications. Originality/value The corrosion rate has been identified for AA7075 SHCs with various concentrations of Al2O3 and SiC and has been compared with that of the base metal and the friction stir processed specimen without reinforcement.

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Microstructural Characteristics and Mechanical Behaviour of AA7075/TiB2 Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.979.40 ◽

2020 ◽

Vol 979 ◽

pp. 40-46 ◽

Cited By ~ 1

Author(s):

P. Loganathan ◽

A. Gnanavelbabu ◽

K. Rajkumar ◽

S. Ayyanar

Keyword(s):

Mechanical Properties ◽

Matrix Material ◽

Titanium Boride ◽

Stir Casting ◽

Phase Identification ◽

X Ray Diffraction ◽

Microstructural Characteristics ◽

Xrd Pattern ◽

Base Matrix ◽

Aa 7075

Titanium Boride (TiB2) particles reinforced with aluminum alloy (AA 7075) composites were developed using the two-step stir casting method. TiB2 with aluminium alloy was varied in 5, 10, 15 weight percentages (wt.%) . The mechanical properties of the composites were assessed through density, hardness, tensile and impact. Factography observations were also evaluated with Scanning Electron Microscopy (SEM) and phase identification of the composite was carried out through X-ray diffraction technique (XRD). The XRD pattern of alloy and composites revealed peaks of Al and TiB2 particles and the intensity of TiB2 particles increased with increase in wt. %. Compared to the base matrix, the density and hardness of composites increased with the wt. % of TiB2. Addition of TiB2 particles exhibited grain refinement, thereby improving the mechanical properties. Composite materials exhibited high load bearing capacity due to the strong bonding of TiB2 and matrix material resulting in increased impact energy. The tensile strength of the composite increased with increasing wt. % of reinforcement. The failure in the composites observed were dimpled structure and ridges, voids, and cracks.

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