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Analytic Estimation of Two-Dimensional Electron Gas Density and Current-Voltage Characteristic in AlGaN/GaN HEMT’s
No full textThis paper is mainly dedicated to understanding the phenomena governing the formation of two-dimensional electron gas confined in the quantum well which hold the role of the channel in the high electron density transistors (HEMT) based on AlGaN / GaN heterojunction. The theory takes into account: the crystal structure, the spontaneous and piezoelectric polarization concept, the formation mechanism of two-dimensional electron gas at the AlGaN / GaN interface, the approximate resolution of the Poisson and Schrödinger equations to determine the density of Two-dimensional electron gas after the analytical formula of the current-voltage characteristic is established. Our study is also concerned with the dependence of the two-dimensional electron gas density on the following technological parameters: Aluminum molare fraction, AlGaN layer thickness and AlGaN layer doping, In order to control the influence of these parameters on the device performance. Finally, the current-voltage characteristic which reflects the variation of the drain-source current as a function of the modulation of the gate voltage has been discussed
Fairness Comparison of TCP Variants over Proactive and Reactive Routing Protocol in MANET
No full textMobile ad hoc networks (MANETs) are applicable in an infrastructureless environment where the mobile devices act as routers and intermediate nodes are used to transfer segments to their final destination. As Transmission control protocol (TCP) was originated for Internet with fundamentally different properties, faces serious challenges when used in mobile ad hoc networks. TCP functionality degrades, due to special properties of MANET such as route failure because of significant change of network topology and link errors. TCP uses Congestion Control Algorithms; TCP Vegas is one of them which claim to have better throughput comparing with other TCP variants in a wired network. Fairness issues of TCP Variants in MANET including existing routing protocol are still unsolved. To determine the best TCP Variants in MANET environment over renowned routing protocol is the main objective of this paper. A Study on the throughput fairness of TCP Variants namely, Vegas, Reno, New Reno, SACK, FACK, and Cubic are performed via simulation experiment using network simulator (ns-2) over existing routing protocol, named, AODV, AOMDV, DSDV, and DSR. This fairness evaluation of TCP flows arranged a contrast medium for the TCP Variants using stated routing protocol in MANET. However, TCP Vegas obtain unfair throughput in MANET. The simulation results show that TCP Reno outperforms other TCP variants under DSDV routing protocol
Exploiting 2-Dimensional Source Correlation in Channel Decoding with Parameter Estimation
No full textTraditionally, it is assumed that source coding is perfect and therefore, the redundancy of the source encoded bit-stream is zero. However, in reality, this is not the case as the existing source encoders are imperfect and yield residual redundancy at the output. The residual redundancy can be exploited by using Joint Source Channel Coding (JSCC) with Markov chain as the source. In several studies, the statistical knowledge of the sources has been assumed to be perfectly available at the receiver. Although the result was better in terms of the BER performance, practically, the source correlation knowledge were not always available at the receiver and thus, this could affect the reliability of the outcome. The source correlation on all rows and columns of the 2D sources were well exploited by using a modified Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm in the decoder. A parameter estimation technique was used jointly with the decoder to estimate the source correlation knowledge. Hence, this research aims to investigate the parameter estimation for 2D JSCC system which reflects a practical scenario where the source correlation knowledge are not always available. We compare the performance of the proposed joint decoding and estimation technique with the ideal 2D JSCC system with perfect knowledge of the source correlation knowledge. Simulation results reveal that our proposed coding scheme performs very close to the ideal 2D JSCC system
An Energy Aware Resource Utilization Framework to Control Traffic in Cloud Network and Overloads
No full textEnergy consumption in cloud computing occur due to the unreasonable way in which tasks are scheduled. So energy aware task scheduling is a major concern in cloud computing as energy consumption results into significant waste of energy, reduce the profit margin and also high carbon emissions which is not environmentally sustainable. Hence, energy efficient task scheduling solutions are required to attain variable resource management, live migration, minimal virtual machine design, overall system efficiency, reduction in operating costs, increasing system reliability, and prompting environmental protection with minimal performance overhead. This paper provides a comprehensive overview of the energy efficient techniques and approaches and proposes the energy aware resource utilization framework to control traffic in cloud networks and overloads
Investigation and Study of Vital Factors in Selection, Implementation and Satisfaction of ERP in Small and Medium Scale Industries
No full textSmall and Medium Scale Enterprises in India are the most productive job designers and forerunners in developing new ideas in the field of business. SMEs not only play a vital role in providing large scale employment openings at reasonably lower capital than large businesses but also help in industrialization of rural areas in India. SMEs are complementary to large industries as subsidiary units and this sector contributes immensely to the socio-economic development of the country. Small and Medium scale industries have grown tremendously in the last 5 decades. In spite of high enthusiasm and intrinsic capabilities to grow, there are a number of problems faced by SME’s; one of them is the ‘technological obsolescence’. The SME sector in order to outcome this challenge must make advances in the field of engineering and technology. Adoption of Information Communication Technology in their business process can enhance their productivity and global competency.in the market. In this connection Enterprise Resource Planning plays a vital role in the SME’s business process strategy. Hence there is a need for the motivation to implement ERP and find whether the current ICT solution the industries using are adequate for their strategy. In this paper we try to find out which ERP vendors does the SME sectors prefer, are the features of the ERP system and the implementation methodology selected have met the business goals and user satisfaction
Performance Analysis of Antenna Selection Techniques in MIMOOFDM System with Hardware Impairments: Energy Efficiency Perspective
No full textIn this paper we propose a new MIMO-OFDM model in which we consider various antenna selection techniques like Bulk selection and Per-subcarrier selection etc. with hardware impairments such as non-linearties of amplifiers, quantization noise, phase noise and I-Q imbalance etc. As we know that the transceiver hardware impairments limit the channel capacity and the energy efficiency of MIMO-OFDM system, so we can not neglect the fundamental impacts of these hardware impairments {Kappa ∈ (0.05 0.1)} on the energy efficiency in the high SNR domain. Therefore we analyze the Energy Efficiency of Bulk and Per-subcarrier antenna selection techniques with or without hardware impairments. It has been observed that the energy efficiency decreases as the value of these hardware impairments increases. As we compared the Bulk antenna selection with the Per-subcarrier antenna selection scheme, the Per-subcarrier antenna selection requires more number of RF (radio frequency) chains and transmits power in comparison to the Bulk selection. Due to this, the Bulk antenna selection technique is more energy efficient than Per-subcarrier antenna selection
BB84 with Both Several Cloning and Intercept-resend Attacks
No full textThe goal of the protocol QKD BB84 is to allow a transmitter and a receiver which uses a quantum channel to exchange their keys and to detect the presence of eavesdropping attacks. In the present research, we investigate the effect of several eavesdroppers with both intercept-resend and cloning attacks. We will propose the different possible cases of the positioning of the eavesdroppers and their strategies of attacks; also we will calculate the mutual information for each case. The explicit expressions of the mutual information and quantum error clearly show that the security of the exchanged information depends on the numbers of the eavesdroppers and their attacks parameters on the quantum channel
The Indonesia Public Information Disclosure Act (UU-KIP): Its Challenges and Responses
No full textInformation Public Disclosure is one of the regulation that has purposes to encourage good governance for public service and citizen participation in national development. The enactment of Act No.14/2008 (UU KIP) has been strengthen the mandate to enforce the necessity of information disclosure in actualizing transparency and accountability in resource management and budget uses. It also become the primary instrument to prevent corruption, monopolistic competition and information disputes. However, there are certain provinces has not yet established information committee nor when it will be as entrusted by the regulation. Meanwhile, the remedies in term of jail duration and fines, arguably, it could not create deterrent effect to the perpetrator. Furthermore, the concern from ministry and public institution also in question in regard their roles of responsibility, lack of cooperation and continuous support. Thus, human resource, technology infrastructure, public participation, supervision and socialization become crucial factor to increase the awareness and satisfaction towards this regulatory compliance. This study is a qualitative research to evaluate the implementation of this Act by observing its consideration, background, principles and relevant article verses as primary sources through content analysis based on number of legal experts
Mixed Linearity Improvement Techniques for Ultra-wideband Low Noise Amplifier
No full textWe present the linearization of an ultra-wideband low noise amplifier (UWB-LNA) operating from 2GHz to 11GHz through combining two linearization methods. The used linearization techniques are the combination of post-distortion cancellation and derivative-superposition linearization methods. The linearized UWB-LNA shows an improved linearity (IIP3) of +12dBm, a minimum noise figure (NFmin.) of 3.6dB, input and output insertion losses (S11 and S22) below -9dB over the entire working bandwidth, midband gain of 6dB at 5.8GHz, and overall circuit power consumption of 24mW supplied from a 1.5V voltage source. Both UWB-LNA and linearized UWB-LNA designs are verified and simulated with ADS2016.01 software using BSIM3v3 TSMC 180nm CMOS model files. In addition, the linearized UWB-LNA performance is compared with other recent state-of-the-art LNAs
Experimental Prototype Model of IDVR for Bidirectional Voltage Compensation
No full textInterline Dynamic Voltage Restorer (IDVR) is an optimum solution to compensate voltage sag in multiple lines. The IDVR consisting of two or more DVRs connected to different feeders in a power system sharing a common DC link energy. This paper presents the hardware implementation of novel bidirectional voltage sag compensation by the IDVR in multiple feeders at same instance. A two line feeder power system with IDVR installed is considered. The IDVR is implemented using two VSI with filter. The control system of IDVR is developed using DSPACE 1103.