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Missouri University of Science and Technology

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Articles 1561 - 1590 of 2222

Full-Text Articles in Mechanical Engineering

An Optimal Control Based Treatment Strategy For Parturient Paresis Using Neural Networks, Radhakant Padhi, S. N. Balakrishnan Jan 2001

An Optimal Control Based Treatment Strategy For Parturient Paresis Using Neural Networks, Radhakant Padhi, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An optimal online feedback treatment strategy is developed for the parturient paresis of cows, based on nonlinear optimal control theory. A limitation in the development of an existing mathematical model for calcium homeostasis is addressed and the model is extended to incorporate control inputs. An optimal feedback controller is synthesized for the nonlinear system using neural networks. Though the main aim of this paper is to solve the biomedical control problem, the methodology presented in this paper is a general computational tool, which can be applied to solve a fairly general class nonlinear optimal control problems.

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Robust State Dependent Riccati Equation Based Robot Manipulator Control, Ming Xin, S. N. Balakrishnan, Zhongwu Huang Jan 2001

Robust State Dependent Riccati Equation Based Robot Manipulator Control, Ming Xin, S. N. Balakrishnan, Zhongwu Huang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We present a new optimal control approach to robust control of robot manipulators in the framework of state dependent Riccati equation (SDRE) technique. To treat this highly nonlinear control system, we formulate it as a nonlinear optimal regulator problem. SDRE technique was used to synthesize an optimal controller to this class of robot control problem. We also synthesize a neural network based extra controller to achieve the robustness in the presence of the parameter uncertainties. A typical two-link robot position control problem was studied to show the effectiveness of SDRE approach and robust extra control design to robotic application.

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Re-Examination Of The Crypto-Steady Pressure-Exchanger (Virtual Turbomachine), T. Scott, David W. Riggins Jan 2001

Re-Examination Of The Crypto-Steady Pressure-Exchanger (Virtual Turbomachine), T. Scott, David W. Riggins

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A crypto-steady pressure-exchanger (rotating center body ejecting fluid in a supersonic flow field) is investigated based on fundamental fluid dynamic principles. The results are then compared to computational fluid dynamic (CFD) simulations of a simplified device. On the basis of this comparison the device studied is correctly classified as an unsteady ejector instead of a type of turbomachinery. Entropy gains (total pressure losses) associated with the complex fluid-fluid and fluid-center body interactions are shown to be greater than total pressure gains due to work addition. Compared to a steady ejector, the virtual turbomachine shows increased entrainment (mixing) of the main …

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A Numerical Study Of Automotive Gas Tank Filler Pipe Two Phase Flow, R. Banerjee, Kakkattukuzhy M. Isaac, L. Oliver, W. Breig Jan 2001

A Numerical Study Of Automotive Gas Tank Filler Pipe Two Phase Flow, R. Banerjee, Kakkattukuzhy M. Isaac, L. Oliver, W. Breig

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Automotive refueling is gaining greater importance because fuel vapors released during refueling are believed to increase ozone levels in urban areas. As a step towards On-Board Refueling Vapor Recovery (ORVR) designs, vapor generation and transport during refueling needs to be understood to develop recovery techniques. The objective of the present study is to understand the fluid flow inside the automotive gas tank filler pipe using commercially available Computational Fluid Dynamics (CFD) software. This effort is expected to yield detailed flow field information, including air entrainment. The phenomena of well-back, the process of fuel flooding the filler pipe and flowing backwards …

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Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker Jan 2001

Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, several states including Missouri, Wyoming, California, and Texas experienced fracture failures of traffic signal mast arms. Almost all the failures are associated with the propagation of defects or cracks. It is therefore imperative to evaluate existing mast arms using a simple yet accurate procedure. A statistical methodology is proposed to predict the fatigue life of signal mast arm structures on the basis of field-measured strain data. The annual occurrence of various stress levels is determined using the historical wind speed data in the vicinity of a mast arm structure and the strain readings of the structure under …

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Robust Adaptive Critic Based Neurocontrollers For Missiles With Model Uncertainties, Zhongwu Huang, S. N. Balakrishnan Jan 2001

Robust Adaptive Critic Based Neurocontrollers For Missiles With Model Uncertainties, Zhongwu Huang, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Lyapunov theory-based controller is proposed in this paper for robustness against model uncertainties in the control of a missile. The controller design consists of two parts; in the first phase, an optimal nonlinear controller is designed with neural networks for tracking. This is based on the adaptive critic method that consists of one neural network called the supervisor or critic and a second network called an action network or a controller. Each network is trained through the output of the other network and equations related to optimal control. When their outputs are mutually consistent, the controller network output is …

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Amplitude Modulated Droplet Formation In High Precision Solder Droplet Printing, Qingbin Liu, M. Orme, Ming-Chuan Leu Jan 2001

Amplitude Modulated Droplet Formation In High Precision Solder Droplet Printing, Qingbin Liu, M. Orme, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

There are many methods used at present to apply solder to wafers, ceramics, laminate and flex circuit boards, and other substrates. Among these, high-precision solder droplet printing technology, which is noncontact, data driven, flexible and environmentally friendly, is a key enabling technology. This technology selectively deposits solder droplets only where required, and therefore needs no mask or secondary resist removal, uses materials more efficiently and creates less waste than other methods. Currently, continuous droplet formation from capillary streams is mainly achieved by application of the well-known Rayleigh instability in which a sinusoidal disturbance is applied to the stream, resulting in …

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Adaptive Critic Based Neuro-Observer, Xin Liu, S. N. Balakrishnan Jan 2001

Adaptive Critic Based Neuro-Observer, Xin Liu, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A new Neural Network (NN) based observer design method for nonlinear systems represented by nonlinear dynamics and linear/nonlinear measurement is proposed in this paper. In this new approach, as the first step, the observer design problem is changed into a "controller" design problem by establishing the error dynamics, and then the Adaptive Critic (AC) based approach is applied on this error dynamics to design a 'controller', such that the errors are driven to zero. The resulting observer has inherent robustness from the AC based design approach. Some simulations are presented to illustrate the effectiveness of this approach.

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Detection And Classification Of Impact-Induced Damage In Composite Plates Using Neural Networks, Rohit Dua, Steve Eugene Watkins, Donald C. Wunsch, K. Chandrashekhara, Farhad Akhavan Jan 2001

Detection And Classification Of Impact-Induced Damage In Composite Plates Using Neural Networks, Rohit Dua, Steve Eugene Watkins, Donald C. Wunsch, K. Chandrashekhara, Farhad Akhavan

Electrical and Computer Engineering Faculty Research & Creative Works

Artificial neutral networks (ANN) can be used as an online health monitoring systems (involving damage assessment, fatigue monitoring and delamination detection) for composite structures owing to their inherent fast computing speeds, parallel processing and ability to learn and adapt to the experimental data. The amount of impact-induced strain on a composite structure can be found using strain sensors attached to composite structures. Prior work has shown that strain-based ANN can characterize impact energy on composite plates and that strain signatures can be associated with damage types and severity. This paper reports the extension of this approach for damage classification using …

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High Precision Solder Droplet Printing Technology: Principle And Applications, Qingbin Liu, M. Orme, Ming-Chuan Leu Jan 2001

High Precision Solder Droplet Printing Technology: Principle And Applications, Qingbin Liu, M. Orme, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Solder droplet printing technology, which is low-cost, noncontact, flexible, data-driven, and environmentally friendly, has emerged as an enabling technology for precisely placing fine solder deposits on a variety of small substrates. It is suitable for a variety of applications including direct chip attach site preparation, 3D substrates, fine line interconnect, substrate via fill, optoelectronics and many others. It enables manufacturing techniques that are impossible or unfeasible with current technology, such as localized replacement of solder on board, depositing solder in different thicknesses on the same board, or using more than one type of solder on the same board. This makes …

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Study On Water Deposit In Rapid Freeze Prototyping Process, Guanghua Sui, Weihan Zhang, Ming-Chuan Leu Aug 2000

Study On Water Deposit In Rapid Freeze Prototyping Process, Guanghua Sui, Weihan Zhang, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Rapid Freeze Prototyping (RFP) builds a three-dimensional ice part according to its CAD model by depositing and rapidly freezing water in a layer-by-layer manner. To study the water deposit in RFP, assumptions are made based on the deformation of water droplet impinging on a flat substrate, the thermal analysis of a new layer of water deposit, and the characteristics of solidification of a water drop. The equations governing the cross-sectional profile of the water deposit are then established. A model of water deposit is proposed by simplifying the equations under our experimental conditions in RFP. By using this model, equations …

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Investment Casting With Ice Patterns Made By Rapid Freeze Prototyping, Wei Zhang, Ming-Chuan Leu, Chao Feng, Rong Ren, Renjie Zhang, Qingping Lu, Jubu Jiang, Yongnian Yan Aug 2000

Investment Casting With Ice Patterns Made By Rapid Freeze Prototyping, Wei Zhang, Ming-Chuan Leu, Chao Feng, Rong Ren, Renjie Zhang, Qingping Lu, Jubu Jiang, Yongnian Yan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the most promising applications of rapid freeze prototyping (RFP) is making metal parts by investment casting with the built ice parts. The integration of RFP and investment casting allows fast creation of complex net-shape metal parts directly from their CAD models. The advantages of doing so include no part geometric complexity limitation, no experience of parting line design and assembling needed, clean and low-cost of process operation, and good performance. In this paper, we will present our recent study on binder selection, slurry making, ceramic shell making, and the casting results of the metal parts.

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Determination And Improvement Of Building Speed In Rapid Freeze Prototyping, Wei Zhang, Guanghua Sui, Ming-Chuan Leu Aug 2000

Determination And Improvement Of Building Speed In Rapid Freeze Prototyping, Wei Zhang, Guanghua Sui, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Rapid freeze prototyping (RFP) is a solid freeform fabrication process that builds an ice part by rapidly freezing water in a layer by layer manner. One advantage of this process is the ability to build ice parts faster than other SFF processes. The factors that affect the speed of contour building and interior filling in RFP are identified. The influence of these factors is analyzed through heat transfer and material flow analyses. A model based on heat transfer analysis is proposed to determine the maximum achievable speed of contour building under stable conditions. Experiments are conducted to validate the performance …

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Laser Additive Manufacturing Process Planning And Automation, Jun Zhang, Jianzhong Ruan, Frank W. Liou Aug 2000

Laser Additive Manufacturing Process Planning And Automation, Jun Zhang, Jianzhong Ruan, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents a Laser Additive Manufacturing Process Planning (LAMPP) being developed at the University of Missouri-Rolla. The off-line planning recognizes difficult-to-build features from an STL file, selects optimal part orientation and building directions based on the skeleton information of the object geometry, and optimizes the sub-process sequences for deposition and machining. During the optimization of the subpart building processes, collaboration between the deposition process planner and the machining process planner is needed to check the deposition availability and machinability. As a result, tool paths for both the laser head and the machining head are automatically generated.

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Process Modeling, Monitoring And Control Of Laser Metal Forming, N. Munjuluri, Sanjeev Agarwal, Frank W. Liou Aug 2000

Process Modeling, Monitoring And Control Of Laser Metal Forming, N. Munjuluri, Sanjeev Agarwal, Frank W. Liou

Electrical and Computer Engineering Faculty Research & Creative Works

Laser Metal Forming (LMF) process is one of the prominent Rapid Prototyping (RP) process that can be used to develop functional and fully dense metal parts. This paper addresses process modeling, monitoring and control of a laser metal forming system currently under development at Laser Aided Manufacturing Processes (LAMP) laboratory at University of Missouri--Rolla. This LMF system is based on a 2.5kW Nd:YAG laser as energy source and integrates five axis metal deposition and five axis machining. The current paper is aimed at characterization of effects of operating parameters such as traverse speed, mass flow-rate and laser power on the …

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High-Temperature Characteristics Of 1.3 Μm Ingaasn:Sb/Gaas Multiple-Quantum-Well Lasers Grown By Molecular-Beam Epitaxy, Xiaodong Yang, J. B. Heroux, M. J. Jurkovic, W. I. Wang Feb 2000

High-Temperature Characteristics Of 1.3 Μm Ingaasn:Sb/Gaas Multiple-Quantum-Well Lasers Grown By Molecular-Beam Epitaxy, Xiaodong Yang, J. B. Heroux, M. J. Jurkovic, W. I. Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

1.3 μm InGaAsN:Sb/GaAs multiple-quantum-well laser diodes have been grown by solid-source molecular-beam epitaxy using Sb as a surfactant. A low threshold of 1.1 kA/cm² was achieved for broad-area laser diodes under pulsed operation at room temperature. High-temperature device characterization revealed characteristic temperatures (T₀) of 92 and 54 K for operating temperatures below and above 75°C, respectively, as well as a lasing-wavelength temperature dependence of 0.36 nm/°C.

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Convergence Analysis Of Adaptive Critic Based Optimal Control, S. N. Balakrishnan, Xin Liu Jan 2000

Convergence Analysis Of Adaptive Critic Based Optimal Control, S. N. Balakrishnan, Xin Liu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Adaptive critic based neural networks have been found to be powerful tools in solving various optimal control problems. The adaptive critic approach consists of two neural networks which output the control values and the Lagrangian multipliers associated with optimal control. These networks are trained successively and when the outputs of the two networks are mutually consistent and satisfy the differential constraints, the controller network output produces optimal control. In this paper, we analyze the mechanics of convergence of the network solutions. We establish the necessary conditions for the network solutions to converge and show that the converged solution is optimal.

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Lifecycle Analysis For Environmentally Conscious Solid Freeform Manufacturing, Yanchun Luo, Ji Zhiming, Ming-Chuan Leu, R. J. Caudill Jan 2000

Lifecycle Analysis For Environmentally Conscious Solid Freeform Manufacturing, Yanchun Luo, Ji Zhiming, Ming-Chuan Leu, R. J. Caudill

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A lifecycle based process model for analyzing the environmental performance of SFM processes and SFM based rapid tooling processes is presented in this paper. The process environmental performance assessment model considers material, energy and disposal scenarios. The material use, process parameters (e.g. scanning speed) and power use can affect the environmental consequence of a process when material resource, energy, human health and environmental damage are taken into account. The presented method is applied to the SLA process and two SLA based rapid tooling processes. The method can be used to compare different rapid prototyping (RP) and RT processes in terms …

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Robust Adaptive Critic Based Neurocontrollers For Systems With Input Uncertainties, S. N. Balakrishnan, Zhongwu Huang Jan 2000

Robust Adaptive Critic Based Neurocontrollers For Systems With Input Uncertainties, S. N. Balakrishnan, Zhongwu Huang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A two-neural network approach to solving optimal control problems is described in this study. This approach called the adaptive critic method consists of two neural networks: one is called the supervisor or critic, and the other is called an action network or controller. The inputs to both these networks are the current states of the system to be controlled. Each network is trained through an output of the other network and the conditions for optimal control. When their outputs are mutually consistent, the controller network output is optimal. The optimality is limited to the underlying model. Hence, we develop a …

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Midcourse Guidance Law With Neural Networks, Dongchen Han, S. N. Balakrishnan Jan 2000

Midcourse Guidance Law With Neural Networks, Dongchen Han, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A neural network-based synthesis of an optimal midcourse guidance law is presented in this study. We use a set of two-neural networks; the first network called 'a critic' outputs the Lagrange's multipliers arising in an optimal control formulation and second network called 'an action network' outputs the optimal guidance/control. In this so-called 'adaptive critic' approach, the inputs to the networks are the current values of the states. This approach needs no external training. System equations, optimality conditions and the costate equations are used in conjunction with the network outputs to provide the targets for the neural networks. When the critic …

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Editorial, Ahmed Noor, Victor Birman Jan 2000

Editorial, Ahmed Noor, Victor Birman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

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Experimental Characterization Of Hygrothermal And Aging Effects In Textile Composites, Lokeswarappa R. Dharani, Samit Roy, V. Gupta, Weiqun Xu, N. Dixon Jan 2000

Experimental Characterization Of Hygrothermal And Aging Effects In Textile Composites, Lokeswarappa R. Dharani, Samit Roy, V. Gupta, Weiqun Xu, N. Dixon

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper summarizes the hygrothermal and physical aging tests that were conducted on AS4/PR500 5HS textile composite laminates. The objectives of the hygrothermal tests were to determine the diffusivity and maximum moisture content of the laminate. Three temperatures and three relative humidity levels (RH) were used in combination to create seven test conditions. In addition, three stress levels and three damage levels were imposed to examine the combined effects of stress and damage on moisture absorption. Short-term creep tests were performed on neat resin at different test temperatures to characterize physical aging of the resin matrix. In addition, creep and …

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Development Of A Functional Basis For Design, Robert B. Stone, Kristin L. Wood Jan 2000

Development Of A Functional Basis For Design, Robert B. Stone, Kristin L. Wood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Functional models represent a form independent blueprint of a product. As with any blueprint or schematic, a consistent language or coding system is required to ensure others can read it. This paper introduces such a design language, called a functional basis, where product function is characterized in a verb-object (function-flow) format. The set of functions and flows is intended to comprehensively describe the mechanical design space. Clear definitions are provided for each function and flow. The functional basis is compared to previous functional representations and is shown to subsume these attempts as well as offer a more consistent classification scheme. …

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A Neural Network Methodology For Path Planning And Coordination Of Car-Like Robots, Prasanna Venkatesan Sadagopan Jan 2000

A Neural Network Methodology For Path Planning And Coordination Of Car-Like Robots, Prasanna Venkatesan Sadagopan

Masters Theses

"A car-like indoor mobile robot is a kinematically constrained robot that can be modeled as a 2D object translating and rotating in the horizontal plane among well- defined obstacles. The kinematic constraints impose that the linear velocity of the robot is along its main axis (no sideways motion is possible) and restrict the range of admissible values for the steering angle. The goal of this study is to combine neural network techniques and motion planning algorithms to create a new methodology for coordinating the motion of multiple car-like robots avoiding collision with polygonal obstacles in a work environment. An incremental …

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Carryover For Hypersonic '+' And 'X' Configuration Delta Fin Missiles, Harlan F. Nelson Jan 2000

Carryover For Hypersonic '+' And 'X' Configuration Delta Fin Missiles, Harlan F. Nelson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Zonal Euler Solver code (ZEUS) is used to predict hypersonic missile flow fields and to determine the carryover factors for the effect of the body on wing lift, Kw(B), and for the effect of the wing on body lift, KB(w). Results are presented for Mach 4, 6, 8, and 10 at an angle of attack of 2 deg. The missile has a conical nose and a cylindrical fuselage with a 1-degree flair angle. Both 'x' and '+' fin configurations are considered. Results are given for 20 and 30 deg semi vertex angles as a function of fur span to …

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Tuning Parameter Tolerance Design: Foundations, Methods, And Measures, Daniel A. Mcadams, Kristin L. Wood Jan 2000

Tuning Parameter Tolerance Design: Foundations, Methods, And Measures, Daniel A. Mcadams, Kristin L. Wood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, a novel technique is presented to solve tolerance design problems. To achieve the desired performance tolerance, the technique uses a subtle, but significant, change in the design: the addition of a tuning parameter in place of an increase in component precision. Statistical models are used to develop a framework for the tuning parameter design method. Also developed is a new, dimensionless design metric which ranks candidate tuning parameters. A step-by-step method is developed for the application of tuning parameters using this metric. The step-by-step tuning parameter design method is applied to a heavy-duty manual stapler as a …

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A Heuristic Method For Identifying Modules For Product Architectures, Robert B. Stone, Kristin L. Wood, Richard H. Crawford Jan 2000

A Heuristic Method For Identifying Modules For Product Architectures, Robert B. Stone, Kristin L. Wood, Richard H. Crawford

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Developing product architectures is a key phase in design and development processes. It encompasses the transformation of product function to alternative product layouts. In this paper, we describe a new approach for identifying modules for product architectures. We begin by reviewing the terminology and motivation for modular products. The new concepts of a functional basis and time ordered function chains are used to formally derive functional models of products. Then, three heuristic methods for identifying modules from functional models are presented. Using the formal functional decomposition and heuristic methods, modular design can be executed earlier in the product development process, …

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Using Quantitative Functional Models To Develop Product Architectures, Robert B. Stone, Kristin L. Wood, Richard H. Crawford Jan 2000

Using Quantitative Functional Models To Develop Product Architectures, Robert B. Stone, Kristin L. Wood, Richard H. Crawford

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Developing product architectures is a key phase in design and development processes. It encompasses the transformation from functional model to alternative product layouts. In this paper, we introduce a methodology for representing a functional model of a product in a quantitative manner. In addition to describing product functionality, the quantitative functional model also incorporates customer need ratings. Product design knowledge can be archived and transmitted in databases using this novel representation. Numerical manipulations of such a database assist in developing product architectures. In particular, product families and customer need ratings for modules are easily computed. Prior to the methodology, a …

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Infinite Time Optimal Neuro Control For Distributed Parameter Systems, S. N. Balakrishnan, Radhakant Padhi Jan 2000

Infinite Time Optimal Neuro Control For Distributed Parameter Systems, S. N. Balakrishnan, Radhakant Padhi

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The conventional dynamic programming methodology for the solution of optimal control, despite having many desirable features, is severely restricted by its computational requirements. However, in recent times, an alternate formulation, known as the adaptive-critic synthesis, has given it a new perspective. In this paper, we have attempted to use the philosophy of adaptive-critic design to the optimal control of distributed parameter systems. An important contribution of this study is the derivation of the necessary conditions of optimality for distributed parameter systems, described in discrete domain, following the principle of approximate dynamic programming. Then the derived necessary conditions of optimality are …

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Effect Of Interfacial Mobility On Flexural Strength And Fracture Toughness Of Glass/Epoxy Laminates, T. W. H. Wang, Frank D. Blum, Lokeswarappa R. Dharani Oct 1999

Effect Of Interfacial Mobility On Flexural Strength And Fracture Toughness Of Glass/Epoxy Laminates, T. W. H. Wang, Frank D. Blum, Lokeswarappa R. Dharani

Chemistry Faculty Research & Creative Works

Mechanical testing and surface fractography were used to characterize the fracture of E-glass fiber reinforced epoxy composites as a function of the silane coupling agent used. gamma-Aminopropyltriethoxysilane (APS) and delta-aminobutyltriethoxysilane (ABS) were used because these have been shown to have different interfacial mobilities at multilayer coverage. The values of the properties studied generally increased from untreated c, as determined from a Mode I translaminar fracture toughness tests, for the untreated composites (10.5 ± 0.4 kJ/m2) was lower than that for the ABS-treated composites (14.3 ± 2.1 kJ/m2) which was lower than that for the APS-treated composites (17.1 ± 2.4 kJ/m2). …

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