，人們提出了“服務(wù)質(zhì)量”（Quality of Service，簡稱Q o S）
的概念。Q o S實際是一系列組件，允許對網(wǎng)上的數(shù)據(jù)進(jìn)行不同處理，并可為其分配不同的優(yōu)
先級。若一個網(wǎng)絡(luò)具備Q o S功能，便可根據(jù)實際需要，對其進(jìn)行配置
sim 文件系統(tǒng)In addition, its quality of service reduces because of reliance on traditional circuit-switched network elements. At that former time, people hoped to build a based system, which could access a centralized server network, would always have access to the latest traffic information and could provide web links. What this trend is a momentous request for mobile services based on high-speed packet data transfer. Hence, a new standard, GPRS, came into being in order to fill people’s bill.
This thesis is about wireless communication in shared radio spectrum. Its origin and
motivation is ideally represented by the two quotations from above. In this thesis, the
support of Quality-of-Service (QoS) in cognitive radio networks is analyzed. New
approaches to distributed coordination of cognitive radios are developed in different
spectrum sharing scenarios. The Wireless Local Area Network (WLAN) 802.11 proto-
col of the Institute of Electrical and Electronics Engineers (IEEE) (IEEE, 2003) with
its enhancement for QoS support (IEEE, 2005d) is taken as basis. The Medium Access
Control (MAC) of 801.11(e) is modified to realize flexible and dynamic spectrum
assignment within a liberalized regulation framework.
The Personal Software Process (PSP) shows engineers how to:
1)manage the quality of their projects
2)make commitments they can meet
3)improve estimating and planning
4)reduce defects in their products
After the successful global introduction during the past decade of the second generation (2G) digital
mobile communications systems, it seems that the third generation (3G) Universal Mobile Communication
System (UMTS) has finally taken off, at least in some regions. The plethora of new services that
are expected to be offered by this system requires the development of new paradigms in the way scarce
radio resources should be managed. The Quality of Service (QoS) concept, which introduces in a natural
way the service differentiation and the possibility of adapting the resource consumption to the specific
service requirements, will open the door for the provision of advanced wireless services to the mass
market.
This paper presents a novel technique to increase
the quality of medical images based on Histogram
Equalization. In the proposed method first we have
applied a noise reduction method and then we apply
some suitable preprocessing on histogram of the
medical images and after that histogram equalization
has been applied on the new histogram. Our proposed
method in despite of its simplicity has better results in
compare to other usual methods based on histogram
equalization. The quality of resulted images after
applying our proposed methods has been tested on a
database (medical images) with a confirmed criterion
by viewer. Also we have considered a mathematical
criterion for comparing our proposed algorithm with
other available methods for contrast enhancement.
Results show the better efficiency of the proposed
method.
