| Title | An approach to reduce complexity in non-linear multiuser detection for DS-CDMA systems |
| Authors | Rekha Agarwal, Prof.B.V.R.Reddy and Prof. K.K.Aggarwal |
| Category | IT and Computing |
| Abstract | We present a method to reduced complexity using switching with existing Parallel Interference Cancellation (PIC) detector based on channel characteristics. The main criterion of taking PIC detector is that it has less Bit Error Rate (BER) and less processing delay than other nonlinear multiuser detectors. This proposed detector reduces overall complexity while maintaining the same performance as PIC detector. The switching mechanism is exploited by performance complexity tradeoff between matched filter detector and PIC detector. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part6/p4/ |
| email | rarun96@rediffmail.com |
| Address | School of IT,
GGSIP University, Kashmere Gate
New Delhi |
| |
| Title | Fast Recursive DCT-LMS Speech enhancement For Performance Enhancement Of Digital Hearing Aid |
| Authors | Sunitha S L, Dr. V. Udayashankara |
| Category | Electronics, Electrotechnics |
| Abstract | Hearing impairment is the number one chronic disability-affecting people in the world. Background noise is particularly damaging to speech intelligibility for people with hearing loss especially for sensorineural loss patients. Several investigations on speech intelligibility have demonstrated that sensorineural loss patients need 5-15 dB higher Signal to Noise Ratio (SNR) than the normal hearing subjects. This paper describes Fast Recursive Discrete Cosine Transform Power Normalized Least Mean Square (simply DCT-LMS) algorithm to improve the SNR and to reduce the convergence rate of the Least Means Square (LMS) for sensorineural loss patients. The Discrete Cosine Transform (DCT) has good ortho-normal, separable, and energy compaction property. Although the DCT does not separate frequencies, it is a powerful signal decorrelator. It is a real valued function and thus can be effectively used in real-time operation. The advantages of DCT-LMS as compared to standard LMS algorithm are shown via SNR and eigenvalue ratio computations. The computer simulations results show superior convergence characteristics of the proposed algorithm and faster convergence speed and better time and frequency characteristics. In this work we have used fast recursive DCT to reduce the number of multiplications and additions. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part1/p1/fastrecursive.pdf |
| email | Sunithanov27@yahoo.co.in |
| Address | JSS Research Foundation SJCE Campus Mysore-570006 |
| |
| Title | FOURIER TRANSFORM OF THE SEQUENCES OF THE PRIMITIVE ROOTS OF THE PRIME NUMBERS |
| Authors | H. K. Terzidis, P. Tzekis |
| Category | Mathematics |
| Abstract | First we study the energy spectra of the sequences corresponding to the primitive roots of the prime numbers. Finally, we study the general case of DFT of the sequences corresponding to the primitive roots of the prime numbers. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part3/p2/ |
| email | tzekis@math.auth.gr |
| Address | Technological Educational Institution of Thessaloniki
School of Sciences - Department of Mathematics
P.O. Box 14561, GR-541 01
Thessaloniki , Greece |
| |
| Title | Growth and Characterization of ZnCdS thin films
By Chemical Bath Deposition Technique |
| Authors | Okoli D. N, A. J. Ekpunobi and C. E. Okeke |
| Category | Physics, Astronomy |
| Abstract | In this paper we report the study of ZnCdS thin films grown on the
microscope glass slide by Chemical Bath Deposition Technique (CBDT). The ‘asdeposited’
ZnCdS thin films were characterized using camspec M501 single beam
scanning UV/VIS Spectrophotometer at normal incidence of light in the
wavelength range of 300-1000nm.
The films have 80.82% absorbance |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part5/p1/chemistry combined all.pdf |
| email | donfadino@yahoo.com |
| Address | Department of Physics and Industrial Physics
Nnamdi Azikiwe University, Akwa.
Department of Physics and Astronomy
University of Nigeria, Nsukka |
| |
| Title | OPTICAL PROPERTIES OF AgAlS2 THIN FILMS PREPARED BY
CHEMICAL BATH DEPOSITION TECHNIQUE (CBDT) |
| Authors | OKOLI D. N , A. J. EKPUNOBI AND C. E. OKEKE |
| Category | Physics, Astronomy |
| Abstract | Thin films of AgAlS2 have been prepared by chemical bath deposition
technique form aqueous solutions of AgNO3.5H2O, Al2 (S04) 3.14H2O, (NH2) 2CS and in which sodium hydroxide solution was used as pH adjuster and EDTA as complexing agents. The films were studied for its optical properties using Camspec M501 single beam scanning UV/VIS Spectrophotometer. The plot of absorption coefficient squared against photon energy showed direct band gap energy of 2.30eV. The films showed refractive index range of 2.47 – 2.61 and average absorbance of 47.55% in the Vis-region. The averaged percentage
transmittance of 33.55% in the Vis-region, and 18.90% reflectance in the same region. Also, the films exhibit average extinction coefficients of 3.8x10-2 and optical conductivity of 5.87x1013 S-1. All these optical properties made this ternary semiconductor to be a potential material for fabrication of solar cells and optoelectronic devices. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part5/p2/AgAlS2.pdf |
| email | donfadino@yahoo.com |
| Address | Department of Physics and Industrial Physics
Nnamdi Azikiwe University,
Awka
Department of Physics and Astronomy
University of Nigeria
Nsukka |
| |
| Title | Reliable MULTI Agent System for E-Business Applications |
| Authors | A. Kannammal, V. Ramachandran, N.Ch.S.N. Iyengar |
| Category | IT and Computing |
| Abstract | Mobile agent technology has become a new paradigm for distributed real-time systems because of their inherent advantages. In any distributed system, along with other issues, survivability and fault tolerance are vital issues for deploying mobile-agent systems. E-business becoming a prominent domain for deploying agent technology, it also faces reliability problems due to the failure of agent platform and communication link etc. The reliability is a factor that may affect the performance, availability, and strategy of mobile agent systems. In this paper, reliability issues of mobile agents, particularly in an e-business environment, are discussed. Models for mobile agent reliability have been developed, and a Shopping Consultant Agent System (SCAS) is built as an experimental mobile agent based e-business application. Reliability problems of the system have been identified, and two simple solutions namely periodic scan and forward echo are implemented. The reliability improvement gained by the solutions is evaluated according to the reliability model developed in this paper. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part6/p2/ |
| email | kannaphd@yahoo.co.in |
| Address | Dept of Computer Technology & Applications
Coimbatore Institute of Tech. Coimbatore |
| |
| Title | Secure Service Management using mobile Devices |
| Authors | Gayatri Mohankrishna , N.Ch.S.N.Iyengar & A. Kannammal |
| Category | IT and Computing |
| Abstract | The wireless link is sensitive from a security point of view because, unlike wired connections, wireless signals can propagate to places well beyond the intended coverage area. A lost or stolen device may not only expose much sensitive and private information stored on the device, but the connectivity options on the mobile may allow unrestricted access to the corporate network. Hence there is a need for a clear and strictly enforced security policy. This paper is a new emerging application in mobiles, which provides information about Next Service request, Encryption and Decryption System on move on their mobile. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part6/p3/ |
| email | nchsniyr@yahoo.com |
| Address | School of Computing Sciences
Vellore Institute of Technology,Deemed University
Vellore-632014,Tamilnadu,India |
| |
| Title | Service Quality Gaps: A Retro Analysis |
| Authors | Mr J. CLEMENT and Dr M. SELVAM |
| Category | Economics |
| Abstract | Some of the most influential models in the service management literature (Gronroos, 1990; Parasuraman et al., 1985) focus on the concept of service quality gap (SQG). Parasuraman at al. (1985) define a pioneering model with five SQGs, the concepts of which are amplified in Brogowicz at al.’s (1990) model. The latter has five types of encompassing gaps: information and feedback-related gaps; design-related gaps; implementation-related gaps; communication-related gaps; and customers’ perceptions and expectations-related gaps. Additionally to this model amplification, other authors (e.g. Brown & Swartz, 1989) have pointed to relevant SQGs that have not been considered previously.
This paper integrates current models and a group of SQGs dispersed through the literature in a new comprehensive model. It draws a link between the model and the stages of a strategy process, emphasizing the SQGs’ impact on the process and raising relevant research questions. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part7/p1/ |
| email | clemns@rediffmail.com |
| Address | Karunya Deemed University, Coimbatore INDIA,School of Commerce and Economics, Bharathidasan University, Trichy INDIA |
| |
| Title | Stochastic behavior and Failure analysis of an automotive assembly process having Human errors using biorhythm approach |
| Authors | Prof. Wg Cdr. S.P. Kaushik, Dr. Sapna Jain & A. K. Singhal |
| Category | Mathematics |
| Abstract | This paper deals with stochastic analysis of an automotive assembly process having N-non identical units arranged in series and these N units have been divided into the three main units viz, Body shop, Paint shop and Assembly shop to understand the logical sequence of the process. Preventive maintenance and corrective measures are simulated with waiting concept in this analysis for four types of failures viz, hardware failures, system’s failures, human error based on various factors like cognitive mapping, behavioral impediments, psychological factors etc. and environmental failure. Hardware failure and human error cause the system to work in reduced efficiency state due to minor failure but it is converted to major failure when the system is to wait for repair. The system will also fail either any ith unit does not function or due to environmental failure (like fire, electricity) and it will have to wait for repair. This mathematical modeling for a car assembly system is made by using supplementary variable technique to obtain the reliability and mean time to failure and then a graphical representation is illustrated to show the importance of various factors of human errors and environmental failure with respect to reliability of the automotive assembly process. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part3/p1/ |
| email | jain_sapna76@rediffmail.com |
| Address | Dr. K.N. Modi Institute of Engg. & Technology, Modinagar, India |
| |
| Title | Study on the Propagation Characteristics of Pulses in Optical Fiber Communication Systems |
| Authors | Ambalam venkatachalapathy Ramprasad and Meenakshi Murugappan |
| Category | Electronics, Electrotechnics |
| Abstract | The one dimensional Nonlinear Schrödinger Equation (NLSE) have wide range of applications in nonlinear optical and Laser physics. The design of new optical systems can be carried out by analyzing the propagation characteristics of the pulses in the fiber media. In this paper we believe that for the first time the NLSE equation was solved by both the scalar and vector approach considering with and without the polarization concepts respectively. Various nonlinear effects like Self phase modulations, Stimulated Raman Scattering and Self steepening effects are considered while solving the equation. As conclusion the propagation characteristic of the pulses in the fiber media is analyzed and verified by simulation. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part1/p2/ |
| email | avramprasad2002@yahoo.co.in.meena67@yahoo.com |
| Address | Department of Electronics and communications Engineering
college of Engineering Anna university ,Guindy –Chennai- 600 015 INDIA |
| |
| Title | TRACEBACKING AND BLOCKING THE SPOOFED PACKETS IN A ISP DOMAIN |
| Authors | V. Murali Bhaskaran, A. M. Natarajan, S. N. Sivanandam |
| Category | IT and Computing |
| Abstract | Internet Protocol (IP) packet traceback system is to identify the origin of sequences of IP packets when the sources IP packet address of these packets are spoofed. IP packet traceback is usually performed at the network layer, with the help of routers and gateways. Several approaches have been proposed to trace IP packets to their origin. The packet marking approach enables routers to probabilistically mark packets with partial path information and tries to reconstruct the complete path from the marked packets. In the most of these approaches, routers and victims (affected systems) are considerably overloaded for marking the packet and reconstructing trace path and also more marked packets are required. This paper focuses on tracing the approximate source of attack with a single packet, with the spoofed source address, without computation by victim. Also, the method helps to identify and eliminate the malicious traffic from bad source. In addition, it also provides more bandwidth for effective traffic from the poor sources to the victim in a single Internet Service Provider (ISP) domain. It is implemented using NS-2 simulator. |
| Issue | 18 |
| Date_posted | 8/20/2006 |
| URL (full text) | http://www.acadjournal.com/2006/v18/part6/p1/ |
| email | vmb@kongu.ac.in |
| Address | Department of Computer Science and Engineering, Kongu Engineering College, Perundurai,Erode-638052, Tamil Nadu, India |
| |
