Surface topography of machined fibre reinforced plastics obtained by stylus instruments and optical profilometers

1998 ◽  
Vol 212 (6) ◽  
pp. 479-488
Author(s):  
E Eriksen ◽  
H N Hansen
Keyword(s):  
Manufacturing Industry ◽  
Control Parameters ◽  
Reinforced Plastics ◽  
Optical Instruments ◽  
The Matrix ◽  
Working Principle ◽  
Reinforced Thermoplastics ◽  
And Control ◽  
Short Glass

In the manufacturing industry it is important to be able to specify and control the surface quality of the components produced. This is often done with stylus profilometers, by which standardized roughness parameters are found. In recent years instruments based on laser autofocusing have been introduced. They use another working principle to obtain the same parameters, but the settings of most of the measuring variables are not standardized. The present study has investigated aspects that have to be taken into account when the roughness of short fibre reinforced thermoplastics is measured by stylus instruments and by optical profilometers. The measurements were performed on machined surfaces with three distinct different roughness levels. The materials were two thermoplastics, polyoxymethylene and polypropylene, reinforced with short glass fibres. The two stylus instruments gave almost identical values, whereas significantly higher roughnesses were measured with one of the two optical instruments. The optical instruments were identical but with different settings of the control parameters, which resulted in large deviations between the values measured. Some of the differences between the two types of instrument are supposed to relate to the different properties of the fibres and the matrix, whereas others seem to relate to the instruments.

Research on Network Control Based on QoS of the Network

2014 ◽  
Vol 989-994 ◽  
pp. 4265-4268
Author(s):  
Yang Zhou
Keyword(s):  
Quality Of Service ◽  
Networked Control Systems ◽  
Network Control ◽  
Control Parameters ◽  
Network Parameters ◽  
Model Combining ◽  
Technology Improvement ◽  
Network Quality ◽  
And Control

With the technology improvement of computer communication and multimedia coding, real time communication such as audio and video is introduced to networks and become a dominant way of communication.In the control of network, the optimization problem of the network controller based on network Quality of service (QoS) is a very important problem in the research of network control. Considering the influence of network quality—of service (QoS) on the control performance,a system model combining the network parameters and the control parameters is established for networked control systems (NCSs). Based on this, the condition dependent on the network parameters and control parameters is presented for the existence of guaranteed cost controllers.LMI).Within the scope of QoS perturbation,the designed controller can not only make the system as hypnotically stable but also guarantee that the system performance index is not greater than the upper bound.

scholarly journals An Overview of Impregnation Methods for Carbon Fibre Reinforced Thermoplastics

2017 ◽  
Vol 742 ◽  
pp. 473-481 ◽  
Author(s):  
Thomas Köhler ◽  
Tim Röding ◽  
Thomas Gries ◽  
Gunnar Seide
Keyword(s):  
Carbon Fibre ◽  
High Performance ◽  
Fibre Production ◽  
Matrix Composites ◽  
Carbon Fibres ◽  
Reinforced Plastics ◽  
Thermoplastic Matrix ◽  
Economic Production ◽  
The Matrix ◽  
Reinforced Thermoplastics

Carbon fibre reinforced plastics (CFRPs) can be classified according to whether the matrix is a thermoset or a thermoplastic. Thermoset-matrix composites are by tradition far more common, but thermoplastic-matrix composites are gaining in importance. There are several techniques for combining carbon fibres with a thermoplastic-matrix system. The composite’s characteristics as well as its manufacturing costs are dependent on the impregnation technique of the carbon fibre and the textile structure respectively. Carbon fibre reinforced thermoplastics (CFRTPs) are suitable for fast and economic production of high-performance components. Despite the higher material costs thermoplastic-matrix systems show cost benefits in comparison to thermoset-matrix due to substantial time savings in the production process. Moreover CFRTPs can be manufactured in large production runs. The commingling of reinforcement fibres with matrix fibres is a well-established process. Another approach is the coating of the carbon fibre with a thermoplastic subsequent to the carbon fibre production (carbonization, activation and deposition of sizing). The latter point is currently subject of research and is a promising method for further increasing the production speed. This paper presents the different possibilities of impregnating carbon fibres with a thermoplastic matrix. Diverse technologies along the process chain of the CFRTP production will be discussed.

scholarly journals Influence of Input and Control Parameters on the Process of Pelleting Powdered Biomass

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4104
Author(s):  
Iuliana Gageanu ◽  
Dan Cujbescu ◽  
Catalin Persu ◽  
Paula Tudor ◽  
Petru Cardei ◽  
...  
Keyword(s):  
Initial Density ◽  
Raw Material ◽  
Control Parameters ◽  
Compression Pressure ◽  
Compression Process ◽  
Influence Of Process Parameters ◽  
Single Pellet ◽  
And Control ◽  
Moisture Increase

This paper presents theoretical and experimental research studying the influence of process parameters on the quality of biomass pellets. A validated mathematical model was developed, expressing the density of biomass pellets as determined by moisture content, compression pressure, process heat, the initial density of the material, pelleting speed and initial volume of the material. The experiments for determining the influence of these parameters on the compression of biomass into pellets and optimizing the process were conducted on a heated single pellet compression device, using fir sawdust as raw material. To describe and study the process, four input and control parameters were varied—raw material moisture, pelleting speed, maximum force applied and pelleting die temperature. From the experiments, it was noticed that overall, moisture and pressure have the most important effect on the compression process and pelleting speed, and heat applied also affected the process. Pellet density decreased when pelleting speed and material moisture increase and the density increased with a higher compression pressure and higher heat during the process.

scholarly journals Μελέτη της επίδρασης της κόπωσης στη διεπιφάνεια ίνας/μήτρας σύνθετων υλικών οργανικής μήτρας και της επίδρασης του φαινομένου στους μηχανισμούς μεταφοράς φορτίων σε μικροσκοπικό επίπεδο, με τη μέθοδο laser Raman spectroscopy

2003 ◽  
Author(s):  
Χρήστος Κοϊμτζόγλου
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Response ◽  
Fatigue Loading ◽  
Laser Raman Spectroscopy ◽  
Interfacial Bond ◽  
Reinforced Plastics ◽  
Laser Raman ◽  
The Matrix ◽  
Reinforcing Material

One of the most important parameters that affect the mechanical response of composites is the quality of the interfacial bond between the matrix and the reinforcing material. Therefore, the aim of the present work is to investigate the effect of fatigue loading on the integrity of the interfacial bond in fibre-reinforced plastics in microscopic level using the laser Raman spectroscopy technique.

Time Delay Modeling and Sample Time Selection for Networked Control Systems

2001 ◽  
Author(s):  
Feng-Li Lian ◽  
James Moyne ◽  
Dawn Tilbury
Keyword(s):  
Time Delay ◽  
Control Systems ◽  
Networked Control Systems ◽  
Network Control ◽  
Performance Characteristics ◽  
Networked Control ◽  
Control Parameters ◽  
And Control ◽  
The Impact

Abstract This paper discusses the impact of network architecture on control performance in a class of distributed control systems called Networked Control Systems (NCS), and provides design considerations related to control quality of performance (QoP) as well as network quality of service (QoS). The integrated network-control system changes the characteristics of time delays between application devices. This study first identifies several key components of the time delay through an analysis of network protocols and control dynamics. The analysis of network and control parameters is used to determine an acceptable working range of sampling periods in an NCS. A network-control simulator and an experimental networked machine tool have been developed to help validate and demonstrate the performance analysis results, and identify the special performance characteristics in an NCS. These performance characteristics are useful guidelines for choosing the network and control parameters when designing an NCS.

Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

1976 ◽  
Vol 34 ◽  
pp. 572-573
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley
Keyword(s):  
Electronic Device ◽  
Point Sources ◽  
High Contrast ◽  
Variable Resistor ◽  
Quality Of Results ◽  
Low Contrast ◽  
Evaporation Source ◽  
And Control ◽  
At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

Probability model for control parameters in the aircraft's information and control systems

2018 ◽  
Vol 2 ◽  
pp. 9-16
Author(s):  
A. Al-Ammouri ◽  
◽  
H.A. Al-Ammori ◽  
A.E. Klochan ◽  
A.M. Al-Akhmad ◽  
...  
Keyword(s):  
Control Systems ◽  
Probability Model ◽  
Control Parameters ◽  
And Control

Boilerplate

2012 ◽  
Author(s):  
Margaret Jane Radin
Keyword(s):  
Economic Efficiency ◽  
Analytical Framework ◽  
Daily Basis ◽  
Regulatory Agencies ◽  
Jury Trial ◽  
Comprehensive Treatment ◽  
New Methods ◽  
And Control ◽  
Fine Print

Boilerplate—the fine-print terms and conditions that we become subject to when we click “I agree” online, rent an apartment, or enter an employment contract, for example—pervades all aspects of our modern lives. On a daily basis, most of us accept boilerplate provisions without realizing that should a dispute arise about a purchased good or service, the nonnegotiable boilerplate terms can deprive us of our right to jury trial and relieve providers of responsibility for harm. Boilerplate is the first comprehensive treatment of the problems posed by the increasing use of these terms, demonstrating how their use has degraded traditional notions of consent, agreement, and contract, and sacrificed core rights whose loss threatens the democratic order. This book examines attempts to justify the use of boilerplate provisions by claiming either that recipients freely consent to them or that economic efficiency demands them, and it finds these justifications wanting. It argues that our courts, legislatures, and regulatory agencies have fallen short in their evaluation and oversight of the use of boilerplate clauses. To improve legal evaluation of boilerplate, the book offers a new analytical framework, one that takes into account the nature of the rights affected, the quality of the recipient's consent, and the extent of the use of these terms. It goes on to offer possibilities for new methods of boilerplate evaluation and control, and concludes by discussing positive steps that NGOs, legislators, regulators, courts, and scholars could take to bring about better practices.

Management and engineering solutions to improve processing stock quality and reduce resource-intensity of mining

2018 ◽  
pp. 56-68
Author(s):  
V. V. Agafonov ◽  
V. Yu. Zalyadinov ◽  
M. E. Yusupov ◽  
N. S. Bikteeva
Keyword(s):  
Development Strategy ◽  
Open Pit ◽  
Mining Operations ◽  
High Concern ◽  
General Production ◽  
Resource Intensity ◽  
Product Output ◽  
And Control ◽  
A Company

Sustainability of mining companies is of of high concern. The problem is specifically acute at companies that are monotownor monosettlement-forming. Sustainability of a mine depends in many ways on product quality and production resource-intensity. This article discusses formation of mineral quality indexes in terms of an open pit chrysotile mine. The studies took into account specific features of operation procedures implemented by each structural division of the mine. The analysis has found managerial and technological inconsistencies which affect quality and marketable product output, as well as efficiency of the mine in whole. The background for efficiency enhancement at a company is, by the authors’ opinion, consolidation of personnel subject to the single development strategy, namely: improvement of production and control efficiency, as well as use of available reserves and resources by means of better setup for production. The proposed approaches to planning mining operations and forming mineral quality allow higher quality of processing stock. In addition, a new model proposed for interaction between structural divisions of a mining company ensures improvement of general production indexes.

EFFICIENT MANAGEMENT SYSTEM OF TEACHING TECHNICAL MEANS AT CENTRAL KINDERGARTEN PEDAGOGY COLLEGE IN INDUSTRIAL REVOLUTION 4.0

2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Vũ Xuân Hùng
Keyword(s):  
Intellectual Development ◽  
Industrial Revolution ◽  
Current Period ◽  
Efficient Management ◽  
Urgent Task ◽  
Creative Learning ◽  
Cognitive Activities ◽  
And Control ◽  
Technical Teaching

In the process of teaching, technical teaching facilities are both a content and a means of conveying information, they help the lecturer organize and control the students' cognitive activities, in addition, they also help students be interested in learning, practice practical skills from which to form active and creative learning methods. Teaching technology is one of the necessary conditions to help teachers carry out their related work of educating, teaching and bringing up, and intellectual development, arouse the inherent intelligence qualities of students. Currently, the management of technical teaching facilities at the Central Kindergartens College has been carried out on a regular basis and achieved certain results, but in fact, there are still many inadequacies. Finding a number of limitations in the management of teaching technical facilities, thereby proposing solutions to overcome those limitations, improve the efficiency of investment, preservation and use of teaching technical facilities in the trend of Industry Revolution 4.0, improving the quality of teaching at Central Kindergarten Pedagogy colleges in the current period is a very important and urgent task.

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