The heart of any system that simulates the physical interaction between objects is collision detection-the ability to detect when two objects have come into contact. This system is also one of the most difficult aspects of a physical simulation to implement correctly, and invariably it is the main consumer of CPU cycles. Practitioners, new to the field or otherwise, quickly discover that the attempt to build a fast, accurate, and robust collision detection system takes them down a long path fraught with perils and pitfalls unlike most they have ever encountered.
When station has frame, it sends
Station listens (for max round trip time)plus small increment
If ACK, fine. If not, retransmit
If no ACK after repeated transmissions, give up
Frame check sequence (as in HDLC)
If frame OK and address matches receiver, send ACK
Frame may be damaged by noise or by another station transmitting at the same time (collision)
Any overlap of frames causes collision
Max utilization 18%
Scope of the Book
For some years, commentators have been predicting the ‘convergence’ of the Internet and mobile industries. But what does convergence mean? Is it just about mobile phones providing Internet access? Will the coming together of two huge industries actually be much more about collision than convergence? In truth, there are lots of possibilities about what convergence might mean, such as: † † † † Internet providers also supply mobile phones – or vice versa, of course.
Abstract The work presented in this paper deals with the problem of the navigation of a mobile robot either in unknown indoor environment or in a partially known one. A navigation method in an unknown environment based on the combination of elementary behaviors has been developed. Most of these behaviors are achieved by means of fuzzy inference systems. The proposed navigator combines two types of obstacle avoidance behaviors, one for the convex obstacles and one for the concave ones.
Of course, biomass and food brought this key trade-off
biomass use: the controversial food or fuel. With two primary uses of biomass
appropriate resolution of this balance is essential for biomass acceptable and beneficial
use in the future. Obvious example of biomass for energy is ethanol misuse
produced from corn, a conversion process is relatively inefficient as well as a direct
Collision course with the way corn as food.
In this book chapter a comparative assessment of modelling and control of mechanical
manipulator is considered. First, kinematic and dynamic modelling of wide range
mechanical manipulators comprising flexible link, flexible joint and mobile manipulators
considered. Then, open-loop optimal control problem is formulated to control of
obtained system. Finally, some applications of method including motion planning
maximum payload determination are illustrated through the computer simulations.
The number of different applications for RFID systems is increasing each year and various research directions have been developed to improve the performance of these systems. With this book InTech continues a series of publications dedicated to the latest research results in the RFID field, supporting the further development of RFID. One of the best ways of documenting within the domain of RFID technology is to analyze and learn from those who have trodden the RFID path.
The second volume of the book concerns the characterization approach of photonic crystals, photonic crystal lasers, photonic crystal waveguides and plasmonics including the introduction of innovative systems and materials. Photonic crystal materials promises to enable all-optical computer circuits and could also be used to make ultra low-power light sources.
The word soliton was coined in 1965 to describe the particle-like properties of pulses propagating in a nonlinear medium . The pulse envelope for solitons not only propagates undistorted but also survives collisions just as particles do. The existence of solitons in optical ﬁbers and their use for optical communications were suggested in 1973 , and by 1980 solitons had been observed experimentally .
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Uniﬁed Approach to Optimal Opportunistic Spectrum Access under Collision Probability Constraint in Cognitive Radio Systems
Magnenat Thalmann and Thalmann 
propose a new classification of computer animation
scenes involving synthetic actors both according to the method of controlling motion and according
to the kinds of interactions the actors have. A motion control method specifies how an actor is
animated and may be characterized according to the type of information to which it is privileged in
animating the synthetic actor. For example, in a keyframe system for an articulated body, the
privileged information to be manipulated is joint angles.
Nobody yet invented the universal formula that govern the provision of air navigation
services for any given combination of air traffic flow, its variability and complexity,
airspace configuration and operational environment. It is only certain that the magic
formula should in order to fit snugly in any case, simultaneously consider variables of
people, procedures, systems and environment. The authors of this book are proving
the statement as their contributions focus on developments in the field of air
navigation services from a wealth of particular different aspects....
Chapter summary: Bridges selectively relay packets between network segments, depending on their data-link layer destination addresses; bridges maintain a single broadcast domain and create separate collision domains; switches improve on the function of bridges by forwarding packets only to their destination systems; switches reduce the collisions on a network and increase the bandwidth available to each computer;...
Chapter summary: Supports multiple cable types and speeds, uses the CSMA/CD MAC mechanism to detect collisions, uses a logical ring topology, uses the token passing MAC mechanism, uses a double ring or star topology, uses the token passing MAC mechanism, runs at speeds up to 11 Mbps, uses the CSMA/CA MAC mechanism.
Chapter summary: Bridges selectively relay packets between network segments, depending on their data-link layer destination addresses; bridges maintain a single broadcast domain and create separate collision domains; switches improve on the function of bridges by forwarding packets only to their destination systems;...and other contents.