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Future broadband wireless access systems are expected to integrate various classes of mobile terminals (MTs), each class with a different type of quality of service (QoS) requirement. When the load on a wireless network is high, the guarantee of QoS for each class of MTs is a challenging task. This study considers two classes of MTs—profiled MTs and nonprofiled or regular MTs. It is assumed that profiled users require a guaranteed QoS. The measure of QoS is the probability of forced termination of a call that was allowed to access the network. Two previous handoff prioritization schemes—(i) prerequest scheme and (ii) guard channel scheme—decrease handoff failure (and hence forced termination). In this work, we compare and contrast both the schemes through extensive simulation and we find that neither guard channel nor channel prerequest scheme can guarantee a desired level of QoS for the profiled MTs. We then propose a novel call-admission control (CAC) algorithm that can maintain any desired level of QoS, while the successful call completion rate is very high. In the proposed algorithm, the new call arrival rate is estimated continuously, and when the estimated arrival rate is higher than a predetermined level, some new calls are blocked irrespective of the availability of channels. The objective of this new call preblocking is to maintain a cell's observed new call arrival rate at no more than the predetermined rate. We show that the proposed method can guarantee any desired level of QoS for profiled users.  相似文献   
34.
In this paper, we propose a shrinkage testimator for the shape parameter λ of an Inverse Gaussian distribution when the estimated value of λ is available in such a way that either λ = λ1 or λ = λ2(>;λ1) is expected. The (α + β)min test for testing the hypothesis H0: λ = λ1 against H1: λ = λ2 is derived. The shrinkage factors are chosen to be the function of the (α + β)min test. The shrinkage testimator is found to be more efficient (in the sense of the MSE) than the UMVUE in certain parametric space.  相似文献   
35.

The most significant issue in the government registry department is the duplicate registry of land in the current scenario. These kinds of problems are increasing day by day by day, which necessitates the advancement of the existing registry process system. It is a manual process that a typical stamp-based or newly not secure online process (only a few places). Use of a manual process, there are many issues in the duplicate registry of a particular land. The final registry, where the landlord has a stamp paper copy and sale deed or a specific number of the property. One receipt copy at the land registry department for their record. Blockchain has emerged as a new technology to resolve or handle the above-said issue of the current system, a distributed ledger that is a timestamp and immutable. Being immutable, forgeries related to the particular land during the registry are not allowed. This concept provides trust and consensus among all entities in the network or system. In this paper, we propose a framework for automated maintains a record of registry papers. This framework will also resolve the most effort to loan clearance operations and provide transparency in government e-governance. The system handled by the blockchain network, instead of existing typical manual processor online registry record maintain the process, it includes: An authentication scheme at multiple levels to make the blockchain-based framework secure, a quick verification for all the stack holders (bank, registry department, buyer, and seller), and apply Smart Contract to automate check the loan process as government norms and facilitate buyer and seller selling and purchase. The obtained consequences are examined against the latest approaches to indicate the supremacy of the proposed framework and provide transparent, accountable, incoherent data with the different government departments.

  相似文献   
36.
A wireless sensor network (WSN) is a prominent technology that could assist in the fourth industrial revolution. Sensor nodes present in the WSNs are functioned by a battery. It is impossible to recharge or replace the battery, hence energy is the most important resource of WSNs. Many techniques have been devised and used over the years to conserve this scarce resource of WSNs. Clustering has turned out to be one of the most efficient methods for this purpose. This paper intends to propose an efficient technique for election of cluster heads in WSNs to increase the network lifespan. For the achievement of this task, grey wolf optimizer (GWO) has been employed. In this paper, the general GWO has been modified to cater to the specific purpose of cluster head selection in WSNs. The objective function for the proposed formulation considers average intra‐cluster distance, sink distance, residual energy, and CH balancing factor. The simulations are carried out in diverse conditions. On comparison of the proposed protocol, ie, GWO‐C protocol with some well‐known clustering protocols, the obtained results prove that the proposed protocol outperforms with respect to the consumption of the energy, throughput, and the lifespan of the network. The proposed protocol forms energy‐efficient and scalable clusters.  相似文献   
37.
In this paper we have designed a Split-radix type FFT unit without using multipliers. All the complex multiplications required for this type of FFT are implemented using Distributed Arithmetic (DA) technique. A method is incorporated to overcome the result overflow problem introduced by DA method. Proposed FFT architecture is implemented in 180 nm CMOS technology at a supply voltage of 1.8 V.  相似文献   
38.
A novel architecture of a pipelined redundant-signed-digit analog to digital converter(RSD-ADC) is presented featuring a high signal to noise ratio(SNR), spurious free dynamic range(SFDR) and signal to noise plus distortion(SNDR) with efficient background correction logic. The proposed ADC architecture shows high accuracy with a high speed circuit and efficient utilization of the hardware. This paper demonstrates the functionality of the digital correction logic of 14-bit pipelined ADC at each 1.5 bit/stage. This prototype of ADC architecture accounts for capacitor mismatch, comparator offset and finite Op-Amp gain error in the MDAC(residue amplification circuit) stages. With the proposed architecture of ADC, SNDR obtained is 85.89 dB, SNR is 85.9 dB and SFDR obtained is 102.8 dB at the sample rate of 100 MHz. This novel architecture of digital correction logic is transparent to the overall system, which is demonstrated by using 14-bit pipelined ADC. After a latency of 14 clocks, digital output will be available at every clock pulse. To describe the circuit behavior of the ADC, VHDL and MATLAB programs are used. The proposed architecture is also capable of reducing the digital hardware. Silicon area is also the complexity of the design.  相似文献   
39.
The non quantized nature of user rate wastes the code capacity in Orthogonal Variable Spreading Factor Codes (OVSF) based Code Division Multiple Access (CDMA) systems. The code sharing scheme in multi code CDMA is proposed to minimize the code rate wastage. The scheme combines the unused (wastage) capacity of already occupied codes to reduce the code blocking problem. Simulation results are presented to show the superiority of the proposed code assignment scheme as compared to existing schemes.
Sunil V. BhooshanEmail:
  相似文献   
40.
In life testing, the failure-time distributions are often specified by choosing an appropriate hazard-rate function. The class of life-time distribution characterized by a linear hazard-rate includes the one-parameter exponential and Rayleigh distributions. Usually the parameters of the linear hazard-rate model are estimated by the method of least squares. This work is concerned with Bayes estimation of the two-parameters from a type-2 censored sample. Monte Carlo simulation is used to compare the Bayes risk of the regression estimator with the minimum Bayes risk. Discrete mixtures of decreasing failure rate distributions are known to have decreasing failure rates. The authors prove that the result holds for continuous mixtures as well  相似文献   
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