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Dynamic Fluidic Sprinkler and Intelligent Sprinkler Irrigation Technologies (Smart Agriculture #3)
by Xingye Zhu Alexander Fordjour Junping Liu Shouqi YuanThis book presents a newly designed dynamic fluidic sprinkler (DFS) to improve hydraulic performance of the existing complete fluidic sprinkler (CFS) under low-pressure conditions. Sprinkler irrigation has high prospects for improving water management in crop production. In recent years, low-pressure water-saving has become an important research content in the field of sprinkler irrigation. It introduces the effect of riser height on rotation uniformity and application rate of the dynamic fluidic sprinkler. It also discusses the intelligent sprinkler irrigation technologies for autonomous and remote sensing system. This book will be a useful reference for researchers and professionals in the field of agriculture and irrigation.
Proceedings of UASG 2019: Unmanned Aerial System in Geomatics (Lecture Notes in Civil Engineering #51)
by Xuan Zhu Kamal Jain Kourosh Khoshelham Anuj TiwariThis volume gathers the latest advances, innovations, and applications in the field of geographic information systems and unmanned aerial vehicle (UAV) technologies, as presented by leading researchers and engineers at the 1st International Conference on Unmanned Aerial System in Geomatics (UASG), held in Roorkee, India on April 6-7, 2019. It covers highly diverse topics, including photogrammetry and remote sensing, surveying, UAV manufacturing, geospatial data sensing, UAV processing, visualization, and management, UAV applications and regulations, geo-informatics and geomatics. The contributions, which were selected by means of a rigorous international peer-review process, highlight numerous exciting ideas that will spur novel research directions and foster multidisciplinary collaboration among different specialists.
Education and Mobilities: Ideas, People and Technologies. Proceedings of the 6th BNU/UCL IOE International Conference in Education (Perspectives on Rethinking and Reforming Education)
by Xudong Zhu Mang Li Qiang Liu Hugh Starkey Jiayong LiThis book gathers selected original papers presented at the Sixth Beijing Normal University - University College London, Institute of Education International Conference in Education, a biennial event organised in partnership between this two universities. Readers will find a wealth of papers and reports on research involving schools and the initial and professional development of teachers, revealing links between research, policy and practice, while also analyzing key themes in education, including public goals and policies, pedagogy, curricula, organisation, resources and technologies, and institutional effectiveness. An essential guide for anyone who wishes to understand the main issues involved in mobilities of ideas, people and technology in the field of education, the book offers an extensive introduction, and can also be used as a resource for empirical and conceptual research into related issues.
Mixed Conducting Ceramic Membranes
by Xuefeng Zhu Weishen YangThis book is intended to bring together into a single book all aspects of mixed conducting ceramic membranes. It provides a comprehensive description of the fundamentals of mixed ionic-electronic conducting (MIEC) membranes from the basic theories and materials to fabrication and characterization technologies. It also covers the potential applications of MIEC membrane technology in industry. This book offers a valuable resource for all scientists and engineers involved in R&D on mixed conducting ceramic membrane technology, as well as other readers who are interested in catalysis in membrane reactor, solid state electrochemistry, solid oxide fuel cells, and related topics. Xuefeng Zhu, PhD, is a Professor at State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, China. Weishen Yang, PhD, is the team leader for Membrane Catalysis and New Catalytic Materials and a DICP Chair Professor at State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, China.
Embedded Systems With Arm (register Mark) Cortex-m Microcontrollers In Assembly Language And C
by Yifeng ZhuSignificant changes in the third edition include updated serial communication description (UART, SPI, and I2C), new serial communication examples, incorporation of GNU gcc compiler, low power modes, modification of example programs from STM32L1 (Cortex-M3) to STM32L4 (Cortex-M4). The book introduces basic programming of ARM Cortex-M cores in assembly and C at the register level, and the fundamentals of embedded system design. It presents basic concepts such as data representations (integer, fixed-point, floating-point), assembly instructions, stack, and implementing basic controls and functions of C language at the assembly level. It covers advanced topics such as interrupts, mixing C and assembly, direct memory access (DMA), system timers (SysTick), multi-tasking, SIMD instructions for digital signal processing (DSP), and instruction encoding/decoding. The book also gives detailed examples of interfacing peripherals, such as general purpose I/O (GPIO), LCD driver, keypad interaction, stepper motor control, PWM output, timer input capture, DAC, ADC, real-time clock (RTC), and serial communication (USART, I2C, SPI, and USB).
Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming
by Yi-Guo Zhu Li-Zhong Liu Ning Ma Ping HuOver the last 15 years, the application of innovative steel concepts in the automotive industry has increased steadily. Numerical simulation technology of hot forming of high-strength steel allows engineers to modify the formability of hot forming steel metals and to optimize die design schemes. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming focuses on hot and cold forming theories, numerical methods, relative simulation and experiment techniques for high-strength steel forming and die design in the automobile industry. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming introduces the general theories of cold forming, then expands upon advanced hot forming theories and simulation methods, including: the forming process, constitutive equations, hot boundary constraint treatment, and hot forming equipment and experiments. Various calculation methods of cold and hot forming, based on the authors' experience in commercial CAE software for sheet metal forming, are provided, as well as a discussion of key issues, such as hot formability with quenching process, die design and cooling channel design in die, and formability experiments. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming will enable readers to develop an advanced knowledge of hot forming, as well as to apply hot forming theories, calculation methods and key techniques to direct their die design. It is therefore a useful reference for students and researchers, as well as automotive engineers.
Phase Behavior of Two-Dimensional Water Confined in Graphene Nanocapillaries (Springer Theses)
by YinBo ZhuIn this book, the authors use molecular dynamics simulations to conduct a comprehensive study of the compression/superheating limit and phase transition of 2D (monolayer, bilayer, and trilayer) water/ice constrained in graphene nanocapillaries. When subjected to nanoscale confinement and under ultrahigh pressure, water and ice behave quite differently than their bulk counterparts, partly because the van der Waals pressure can spark a water-to-ice transformation, known as the metastability limit of two-dimensional (2D) liquids. From a mechanical standpoint, this liquid-to-solid transformation characterizes the compression limit (or metastability limit) of 2D water. The findings presented here could help us to better understand the phase behavior of 2D confined water/ice.
Fire-Resistant Paper: Materials, Technologies, and Applications (Emerging Materials and Technologies)
by Ying-Jie ZhuEven in today's electronic information age, traditional paper is a multi-purpose product that continues to be indispensable to people’s daily work and lives. While paper is a valued product, the paper industry contributes to environmental pollution and consumption of natural resources, and the organic substances out of which traditional paper is made render it highly flammable and easy to burn. This book introduces a new technology to develop environmentally friendly fire-resistant paper using highly flexible ultralong hydroxyapatite nanowires and discusses applications and potential for commercialization. Discusses characterization, properties, and synthesis of ultralong hydroxyapatite nanowires and compares them with cellulose fibers Describes steps to design and create fire-resistant paper Covers a variety of function-based fire-resistant paper, including antibacterial, magnetic, photoluminescent, among others Examines a host of applications, such as paper for anti-counterfeiting, encryption and decryption, environmental, energy, and biomedical uses Considers commercialization potential and future prospects This book is aimed at materials scientists, chemical engineers, industrial chemists, and other researchers from across the scientific and engineering disciplines interested in the development of this exciting alternative to traditional paper.
Micro and Nano Machined Electrometers
by Yong ZhuThis book reviews advances in cutting-edge micro-/nano-electrometers, and discusses the technological challenges involved in their practical implementation. The detection of electrostatic charge has a wide range of applications in ionization chambers, bio-analyte and aerosol particle instruments, mass spectrometers, scanning tunneling microscopes, and even quantum computers. Designing micro-/nano-electrometers (also known as charge sensors) for electrometry is considered vital because of the charge sensitivity and resolution issues at micro-/nano-scales. The remarkably dynamic microelectromechanical systems (MEMSs)/nanoelectromechanical systems (NEMSs), and advances in solid-state electronics, hold considerable potential for the design and fabrication of extremely sensitive charge sensors.
Communication, Computation and Perception Technologies for Internet of Vehicles
by Yongdong Zhu Yue Cao Wei Hua Lexi XuThis book focuses on the design, management, and cybersecurity of connected and autonomous vehicles under the umbrella of the Internet of Vehicles. Both principles and engineering practice are covered, from the design perspectives of communication, computing, and perception to ITS management. An in-depth study of a range of topics such as microscopic traffic behavior modeling and simulation, localization, V2X communication, cooperative cloud-edge computing, and multi-sensor fusion for perception has been presented, while novel enabling technologies such as RIS and blockchain are introduced. The book benefits researchers, engineers, and graduate students in the fields of intelligent transport systems, telecommunications, cybersecurity, and autonomous driving.
Uncertain Optimal Control (Springer Uncertainty Research Ser.)
by Yuanguo ZhuThis book introduces the theory and applications of uncertain optimal control, and establishes two types of models including expected value uncertain optimal control and optimistic value uncertain optimal control. These models, which have continuous-time forms and discrete-time forms, make use of dynamic programming. The uncertain optimal control theory relates to equations of optimality, uncertain bang-bang optimal control, optimal control with switched uncertain system, and optimal control for uncertain system with time-delay. Uncertain optimal control has applications in portfolio selection, engineering, and games. The book is a useful resource for researchers, engineers, and students in the fields of mathematics, cybernetics, operations research, industrial engineering, artificial intelligence, economics, and management science.
Power System Loads and Power System Stability (Springer Theses)
by Yue ZhuThis thesis develops a pioneering methodology and a concept for identifying critical loads and load model parameters in large power networks based on their influence on power system stability. The research described in the thesis first develops an automatic load modelling tool (ALMT) that can be used to automatically build load model from actual measured power system data without human intervention and the benefits of the ALMY are explored. Secondly, it develops a pioneering framework based on Morris screening method for ranking power system load model parameters based on their influence on overall power system stability (voltage, frequency, transient and small disturbance stability) considering different load models and loading conditions. Thirdly, a novel probabilistic methodology for determining the accuracy levels of critical load model parameters has been developed. This book will be of interest to students and researchers within the field of electrical engineering, as well as industry professionals.
The Key Technologies for Powertrain System of Intelligent Vehicles Based on Switched Reluctance Motors (Recent Advancements in Connected Autonomous Vehicle Technologies #1)
by Yueying ZhuThis book is intended for engineer’s in automotive industry and in research community of electrical machines. This book systematically focus on all the major aspects of switched reluctance motor for intelligent electric vehicle applications, including optimization design, drive system control, regenerative braking control, and motor-suspension system control, which is particularly suited for readers who are interested to learn the theory of the motor used for intelligent electric vehicles.The comprehensive and systematic treatment of practical issues around switched reluctance motor considering vehicle requirments is one of the major features of the book. The book can benefit researchers, engineers, and graduate students in fields of switched reluctance motor, electric vehicle drive system, regenerative braking system, motor-suspension system, etc.
Networked Multisensor Decision and Estimation Fusion: Based on Advanced Mathematical Methods
by Yunmin Zhu Jie Zhou Xiaojing Shen Enbin Song Yingting LuoDue to the increased capability, reliability, robustness, and survivability of systems with multiple distributed sensors, multi-source information fusion has become a crucial technique in a growing number of areas-including sensor networks, space technology, air traffic control, military engineering, agriculture and environmental engineering, and i
Analysis and Design of Nonlinear Systems in the Frequency Domain (Springer Theses)
by Yunpeng ZhuThis book focuses on the development of three novel approaches to build up a framework for the frequency domain analysis and design of nonlinear systems. The concepts are derived from Volterra series representation of nonlinear systems which are described by nonlinear difference or differential equations. Occupying the middle ground between traditional linear approaches and more complex nonlinear system theories, the book will help readers to have a good start to analyse and exploit the nonlinearities. Analysis and Design of Nonlinear Systems in the Frequency Domain provides clear illustrations and examples at the beginning and the end of each chapter, respectively, making it of interest to both academics and practicing engineers.
Sensorless Control of Permanent Magnet Synchronous Machine Drives (IEEE Press Series on Control Systems Theory and Applications)
by Zi Qiang Zhu Xi Meng WuSensorless Control of Permanent Magnet Synchronous Machine Drives A comprehensive resource providing basic principles and state-of-the art developments in sensorless control technologies for permanent magnet synchronous machine drives Sensorless Control of Permanent Magnet Synchronous Machine Drives highlights the global research achievements over the last three decades and the sensorless techniques developed by the authors and their colleagues, and covers sensorless control techniques of permanent magnet machines, discussing issues and solutions. Many worked application examples are included to aid in practical understanding of concepts. Written by pioneering authors in the field, Sensorless Control of Permanent Magnet Synchronous Machine Drives covers topics such as: Permanent magnet brushless AC and DC drives Single three-phase, dual three-phase, and open winding machines Modern control theory based sensorless methods, covering model reference adaptive system, sliding mode observer, extended Kalman filter, and model predictive control Flux-linkage and back-EMF based methods for non-salient machines, and active flux-linkage and extended back-EMF methods for salient machines Pulsating and rotating high frequency sinusoidal and square wave signal injection methods with current or voltage response, at different reference frames, and selection of amplitude and frequency for injection signal Sensorless control techniques based on detecting third harmonic or zero-crossings of back-EMF waveforms Parasitic effects in fundamental and high frequency models, impacts on position estimation and compensation schemes, covering cross-coupling magnetic saturation, load effect, machine saliency and multiple saliencies Describing basic principles, examples, challenges, and practical solutions, Sensorless Control of Permanent Magnet Synchronous Machine Drives is a highly comprehensive resource on the subject for professionals working on electrical machines and drives, particularly permanent magnet machines, and researchers working on electric vehicles, wind power generators, household appliances, and industrial automation.
Third Harmonic Utilization in Permanent Magnet Machines
by Zi-Qiang Zhu Kai WangThis book investigates the utilization of harmonics in the permanent magnet (PM) or rotor shape to improve the torque density of PM brushless AC machines including three-phase inner rotor and outer rotor machines, five-phase machines, dual three-phase machines, linear machines, by means of analytical, finite element analyses, and as well as experimental validation. The torque density can be improved while the torque ripple remains low in PM shaping utilizing the 3rd harmonic. In this book, the analytical expression of output torque is derived for PM machines with rotor shape using the 3rd harmonic, and then the optimal 3rd harmonic for maximizing torque is analytically obtained. The book compares the PM shape in surface-mounted PM (SPM) machines and the rotor lamination shape in interior PM (IPM) machines utilizing the 3rd harmonic, and it becomes clear that their shaping methods and amount of torque improvement are different. In a five-phase PM machine, the 3rd harmonic can be utilized in both the current waveform and PM shapes to further improve the output torque. For the dual three-phase SPM machines without deteriorating the torque more than 30% when the optimal 3rd harmonic into both the current and PM shape are injected.The harmonics in airgap flux density have significant influence on the cogging torque, stator iron flux distribution, and radial force between the rotor and stator. These effects has been investigated as well in this book.
Solid-Liquid Two-Phase Flow in Centrifugal Pump (Fluid Mechanics and Its Applications #136)
by Zuchao Zhu Yi Li Zhe LinThis book conducts a systematic study on internal flow characteristics and performance of centrifugal pump for solid–liquid mixed transportation. First, the applicability of the computational model for two-phase flow is analyzed. Then the relationship between the two-phase flow characteristics and wall wear in the pipeline is revealed. And the flow characteristics in centrifugal pumps are analyzed in relation to conveying performance and wall wear. Finally, the engineering application calculation of the mixed transportation pump with different impeller structures is carried out. The target audience of this book is researchers who perform calculations and engineering applications of solid–liquid two-phase pumps.This book considers the influence of the particle size on the force magnitude of the particles and analyzes the applicability of different solid–liquid two-phase calculation models. Considering the different motion trajectories of particles colliding with dry wall, wet wall, stationary wall, and moving wall, visual experiments are used to study the collision rebound model of different walls. The collision rebound model is applied to the numerical simulation of solid–liquid mixed transport.
Camera-Aided Robot Calibration
by Hangi Zhuang Zvi S. RothRobot calibration is the process of enhancing the accuracy of a robot by modifying its control software. This book provides a comprehensive treatment of the theory and implementation of robot calibration using computer vision technology. It is the only book to cover the entire process of vision-based robot calibration, including kinematic modeling, camera calibration, pose measurement, error parameter identification, and compensation.The book starts with an overview of available techniques for robot calibration, with an emphasis on vision-based techniques. It then describes various robot-camera systems. Since cameras are used as major measuring devices, camera calibration techniques are reviewed.Camera-Aided Robot Calibration studies the properties of kinematic modeling techniques that are suitable for robot calibration. It summarizes the well-known Denavit-Hartenberg (D-H) modeling convention and indicates the drawbacks of the D-H model for robot calibration. The book develops the Complete and Parametrically Continuous (CPC) model and the modified CPC model, that overcome the D-H model singularities. The error models based on these robot kinematic modeling conventions are presented.No other book available addresses the important, practical issue of hand/eye calibration. This book summarizes current research developments and demonstrates the pros and cons of various approaches in this area. The book discusses in detail the final stage of robot calibration - accuracy compensation - using the identified kinematic error parameters. It offers accuracy compensation algorithms, including the intuitive task-point redefinition and inverse-Jacobian algorithms and more advanced algorithms based on optimal control theory, which are particularly attractive for highly redundant manipulators. Camera-Aided Robot Calibration defines performance indices that are designed for off-line, optimal selection of measurement configurations. It then describes three approaches: closed-form, gradient-based, and statistical optimization. The included case study presents experimental results that were obtained by calibrating common industrial robots. Different stages of operation are detailed, illustrating the applicability of the suggested techniques for robot calibration. Appendices provide readers with preliminary materials for easier comprehension of the subject matter. Camera-Aided Robot Calibration is a must-have reference for researchers and practicing engineers-the only one with all the information!
From Coal to Hydrogen: A Long Journey of Energy Transition (Synthesis Lectures on Chemical Engineering and Biochemical Engineering)
by Qianlin ZhuangThe book tells the story of the coal gasification technology from its early days 230 years ago to the present. Before the end of WWII, gasification had been extensively used to produce both fuel gas and gaseous feedstock from coal. But things have changed when natural gas became readily available, and coal gasification received little attention, especially in recent years when the trend is to move away from fossil energy. Compared to conventional coal combustion, gasification-based processes for power production typically result in much lower emissions of pollutants. So, coal gasification technology became relevant again during the transition of energy production to cleaner sources, in an effort to fight climate change. Taking another look at gasification technology to better understand its potential benefits including carbon capture and management and use the process, seems to make sense during the challenging time of the transition of energy production. Professionalsand policy makers in the energy field will benefit from this writing.
Robotic Micromanipulation of Zebrafish Larva (Synthesis Lectures on Biomedical Engineering)
by Songlin Zhuang Gefei Zhang Dongxu Lei Xinghu Yu Mingsi Tong Weiyang Lin Yang Shi Huijun GaoThis book offers readers a series of robotic methods for manipulating zebrafish larva, one of the most popular model vertebrates widely used in biomedical research and clinical applications. The authors leverage advanced control theories, image processing algorithms, and artificial intelligence to establish a robot-assisted automated or semi-automated zebrafish larva-targeted micromanipulation system for different experimental purposes. The methods presented are generic and can be translated to manipulate other types of biological objects, such as embryos or cells. Coverage includes topics that span the procedures of manipulating zebrafish larva, such as in-plane positioning, three-dimensional orientation, deformation-controllable immobilization, organ-targeted microinjection, whole-organism imaging, and high-throughput trajectory tracking of zebrafish larvae group movement.Robotic Micromanipulation of Zebrafish Larva is written in a simple, clear, and easy-to-read style. It is an ideal reference for academic researchers and biomedical operators. It is also a valuable resource for students learning robotics, control and system theories, image processing, artificial intelligence, and biomedical engineering.
Design, Synthesis and Applications of One-Dimensional Chalcogenide Hetero-Nanostructures
by Tao-Tao ZhuangThis thesis focuses on the design and synthesis of novel one-dimensional colloidal chalcogenide hetero-nanostructures for enhancing solar energy conversion applications. Semiconducting nanomaterials are particular attractive for energy conversion due to the quantum confinement effects dictating their unique optical and electronic properties. Steering the photo-induced charge-flow based on unique bandgap alignment in semiconductor heterojunctions is critical for photo-electric/chemical conversion.The author presents the controllable preparation strategies to synthesize 1D chalcogenide hetero-nanostructures with various fine structures, further been used as excellent template materials for preparing other novel and complex hybrid architectures through a series of chemical transformations. The heterogeneous growth mechanisms of novel hetero-nanostructures is studied for developing a facile and general method to prepare more novel heterostructures. The band gap structure simulations, detailed charge carrier behaviour and unique solar energy conversion properties of the prepared hybrid nanostructures are deeply investigated. This work would open a new door to rationally designing hybrid systems for photo-induced applications.
Cooperative Networking in a Heterogeneous Wireless Medium (SpringerBriefs in Computer Science)
by Weihua Zhuang Muhammad IsmailThis brief focuses on radio resource allocation in a heterogeneous wireless medium. It presents radio resource allocation algorithms with decentralized implementation, which support both single-network and multi-homing services. The brief provides a set of cooperative networking algorithms, which rely on the concepts of short-term call traffic load prediction, network cooperation, convex optimization, and decomposition theory. In the proposed solutions, mobile terminals play an active role in the resource allocation operation, instead of their traditional role as passive service recipients in the networking environment.
Dynamic Resource Management in Service-Oriented Core Networks (Wireless Networks)
by Weihua Zhuang Kaige QuThis book provides a timely and comprehensive study of dynamic resource management for network slicing in service-oriented fifth-generation (5G) and beyond core networks. This includes the perspective of developing efficient computation resource provisioning and scheduling solutions to guarantee consistent service performance in terms of end-to-end (E2E) data delivery delay. Network slicing is enabled by the software defined networking (SDN) and network function virtualization (NFV) paradigms. For a network slice with a target traffic load, the E2E service delivery is enabled by virtual network function (VNF) placement and traffic routing with static resource allocations. When data traffic enters the network, the traffic load is dynamic and can deviate from the target value, potentially leading to QoS performance degradation and network congestion. Data traffic has dynamics in different time granularities. For example, the traffic statistics (e.g., mean and variance) can be non-stationary and experience significant changes in a coarse time granularity, which are usually predictable. Within a long time duration with stationary traffic statistics, there are traffic dynamics in small timescales, which are usually highly bursty and unpredictable. To provide continuous QoS performance guarantee and ensure efficient and fair operation of the network slices over time, it is essential to develop dynamic resource management schemes for the embedded services in the presence of traffic dynamics during virtual network operation. Queueing theory is used in system modeling, and different techniques including optimization and machine learning are applied to solving the dynamic resource management problems.Based on a simplified M/M/1 queueing model with Poisson traffic arrivals, an optimization model for flow migration is presented to accommodate the large-timescale changes in the average traffic rates with average E2E delay guarantee, while addressing a trade-off between load balancing and flow migration overhead. To overcome the limitations of Poisson traffic model, the authors present a machine learning approach for dynamic VNF resource scaling and migration. The new solution captures the inherent traffic patterns in a real-world traffic trace with non-stationary traffic statistics in large timescale, predicts resource demands for VNF resource scaling, and triggers adaptive VNF migration decision making, to achieve load balancing, migration cost reduction, and resource overloading penalty suppression in the long run. Both supervised and unsupervised machine learning tools are investigated for dynamic resource management. To accommodate the traffic dynamics in small time granularities, the authors present a dynamic VNF scheduling scheme to coordinate the scheduling among VNFs of multiple services, which achieves network utility maximization with delay guarantee for each service. Researchers and graduate students working in the areas of electrical engineering, computing engineering and computer science will find this book useful as a reference or secondary text. Professionals in industry seeking solutions to dynamic resource management for 5G and beyond networks will also want to purchase this book.
Distributed Medium Access Control in Wireless Networks
by Weihua Zhuang Ping WangThis brief investigates distributed medium access control (MAC) with QoS provisioning for both single- and multi-hop wireless networks including wireless local area networks (WLANs), wireless ad hoc networks, and wireless mesh networks. For WLANs, an efficient MAC scheme and a call admission control algorithm are presented to provide guaranteed QoS for voice traffic and, at the same time, increase the voice capacity significantly compared with the current WLAN standard. In addition, a novel token-based scheduling scheme is proposed to provide great flexibility and facility to the network service provider for service class management. Also proposed is a novel busy-tone based distributed MAC scheme for wireless ad hoc networks and a collision-free MAC scheme for wireless mesh networks, respectively, taking the different network characteristics into consideration. The proposed schemes enhance the QoS provisioning capability to real-time traffic and, at the same time, significantly improve the system throughput and fairness performance for data traffic, as compared with the most popular IEEE 802.11 MAC scheme.