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A directionally based bandwidth reservation scheme for call admission control
This paper proposes a new advanced Call Admission Control(CAC) strategy involving for the first time, a bandwidth reservation scheme that is influenced by the direction attribute of a mobile terminal (MT). Aside from the Quality-of-Service (QoS) parameters, the direction attribute plays a key role in efficiently reserving resources for MTs supporting multimedia communications for different QoS classes. The framework for a direction-based CAC system is entirely distributed and may be viewed as a message passing system, where MTs inform their neighbouring base stations (BS) not only of their QoS requirements, but also of their mobility parameters. The base stations then predict future demand and reserve resources accordingly, only admitting those terminals that can be adequately supported. The bandwidth reservation scheme proposed in this paper, integrates the direction attribute into the conventional Guard Channel (GC) scheme. Simulation results prove that this new scheme offers significant improvements in both Call Blocking Probability (CBP) and bandwidth utilization, under a variety of differing traffic conditions
Hierarchical Design Based Intrusion Detection System For Wireless Ad hoc Network
In recent years, wireless ad hoc sensor network becomes popular both in civil
and military jobs. However, security is one of the significant challenges for
sensor network because of their deployment in open and unprotected environment.
As cryptographic mechanism is not enough to protect sensor network from
external attacks, intrusion detection system needs to be introduced. Though
intrusion prevention mechanism is one of the major and efficient methods
against attacks, but there might be some attacks for which prevention method is
not known. Besides preventing the system from some known attacks, intrusion
detection system gather necessary information related to attack technique and
help in the development of intrusion prevention system. In addition to
reviewing the present attacks available in wireless sensor network this paper
examines the current efforts to intrusion detection system against wireless
sensor network. In this paper we propose a hierarchical architectural design
based intrusion detection system that fits the current demands and restrictions
of wireless ad hoc sensor network. In this proposed intrusion detection system
architecture we followed clustering mechanism to build a four level
hierarchical network which enhances network scalability to large geographical
area and use both anomaly and misuse detection techniques for intrusion
detection. We introduce policy based detection mechanism as well as intrusion
response together with GSM cell concept for intrusion detection architecture.Comment: 16 pages, International Journal of Network Security & Its
Applications (IJNSA), Vol.2, No.3, July 2010. arXiv admin note: text overlap
with arXiv:1111.1933 by other author
Development of a Device for Remote Monitoring of Heart Rate and Body Temperature
We present a new integrated, portable device to provide a convenient solution
for remote monitoring heart rate at the fingertip and body temperature using
Ethernet technology and widely spreading internet. Now a days, heart related
disease is rising. Most of the times in these cases, patients may not realize
their actual conditions and even it is a common fact that there are no doctors
by their side, especially in rural areas, but now a days most of the diseases
are curable if detected in time.
We have tried to make a system which may give information about one's
physical condition and help him or her to detect these deadly but curable
diseases. The system gives information of heart rate and body temperature
simultaneously acquired on the portable side in real time and transmits results
to web. In this system, the condition of heart and body temperature can be
monitored from remote places. Eventually, this device provides a low cost,
easily accessible human health monitor solution bridging the gaps between
patients and doctors
Low loss topas based porous core single mode photonic crystal fiber for THz communications
In this paper, an extremely low loss hybrid hexagonal porous core and octagonally structured circular cladding photonic crystal fiber (PCF) for low loss terahertz (THz) wave propagation has been designed and proposed. We have analyzed ultralow effective material loss (EML), high core power fraction and ultra-flattened dispersion in our proposed design. To investigate the transmission characteristics, perfectly matched layer (PML) is used in the outer boundary of the PCF. At an operating frequency of 1 THz, this design exhibits a low effective material loss of 0.045 cm-1 at a high core power fraction of 58.2% with 88% porosity. The proposed PCF shows dispersion variation of 0.225 ps/THz/cm. Also, this designed PCF can operate in single-mode condition successfully. It is anticipated that designed PCF can be employed in applications such as fiber optics communications, sensing and spectroscopy
Topas based high birefringent and low loss single mode hybrid-core porous fiber for broadband application
We present a through numerical analysis of a low loss and highly birefringent hybrid porous core with octagonal cladding structure for terahertz (THz) wave guidance. The proposed photonic crystal fiber (PCF) offers simultaneously low effective material loss (EML) as well as high birefringence in the frequency range of 0.8-1.05 THz with single mode operation. To attain high birefringence we introduce asymmetry in the core using both elliptical and circular air holes (hybrid). The numerical results obtained from the finite element method (FEM) which confirms low EML of 0.044 cm–1 as well as a high birefringence of ~0.043 at 0.73 THz operating frequency. Therefore, the fiber is likely to be useful in different THz polarization maintaining applications
Inter-organizational supply chain performance: How the relationship factors influence the Australian beef industry?
This study examines supply chain structures and inter-organizational relationship factors that influence the supply chain performance in the Australian beef industry. It investigated the extent to which aggregated relationship strength is a source of supply chain performance for the industry. The effect of antecedent factors such as vertical coordination, negotiation power and the use of IOS in the relationship strength were also investigated. Data were collected through a telephone survey in 315 firms including input suppliers, producers, processors and retailers in the beef industry of Western Australia and Queensland. The results support both the direction of theoretical underpinnings from RBV and TCE in the beef industry, that durable buyer-supplier relationships in the supply chain are developed from the level of commitment and trust, interdependence and mutual investment and can be a strategic economic resource to by-pass the cost of traditional market transactions. Results suggest the following key success factors for the beef industry in Australia: (a) the operational adoption of a lean supply chain between producer and processors or processors and retailers; (b) a transparent interdependent relationship with a strong consolidation/integration of business activities; and (c) synchronized information flows for greater compliance with carcass specifications in the supply chain
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