iosr-JECE   Volume-7 ~ Issue-1

Abstract: We present a new algorithm, called the soft-tissue filter that can make both soft and bone tissue clearly visible in digital cephalic radiographies under a wide range of exposures. It uses a mixture model made up of two Gaussian distributions and one inverted lognormal distribution to analyze the image histogram. The image is clustered in three parts: background, soft tissue, and bone using this model. Improvement in the visibility of both structures is achieved through a local transformation based on gamma correction, stretching, and saturation, which is applied using different parameters for bone and soft-tissue pixels. A processing time of 1 s for 5 M pixel images allows the filter to operate in real time. Although the default value of the filter parameters is adequate for most images, real-time operation allows adjustment to recover under- and overexposed images or to obtain the best quality subjectively. The filter was extensively clinically tested: quantitative and qualitative results are reported here

Index Terms: Digital radiography, histogram-based clustering, image enhancement, local gamma correction,

[1] R. E. Moyers, Handbook of Orthodontics.Chicago, IL: Year Book,1988

[2] Y. Chen, K. Cheng, and J. Lin, "Feature subimage extraction for cephalogramlandmarking," in Proc. IEEE EMBS, 1998, pp. 1414–1417.

[3] B. Chanda and D. D. Majumder, Digital Image Processing and Analisys.New Delhi, India: Prentice-Hall of India Ptv. Ltd., 2000.

[4] T.-H. Lin and T. Kao, "Adaptive local contrast enhancement method formedical images diplayed on a video monitor," Med. Eng. Phys., vol. 22,pp. 79–87, Mar. 2000.

[5] D.-C. Chang and W.-R. Wu, "Image contrast enhancement based on ahistogram transformation of local standard deviation," IEEE Trans. Med.Imag., vol. 17, no. 8, pp. 518–531, Aug. 1998.

Abstract: OFDM is a modulation as well as multiplexing technique which is widely used in various high speed mobile and wireless communication systems because of its capacity of ensuring high level robustness against interference. In this paper the design and implementation of OFDM system along with SLM implementation to reduce PAPR[6]is illustrated and a detailed simulation of the OFDM system with 16-QAM. OFDM transceiver is implemented using FPGA Spartan6 kit. The hardware results show a detailed study of RTL schematics and Test Bench. In this paper, the software simulation results show 2dB reduction in the peaks.

Keywords - Field Programmable Gate Array, Matlab Simulink, Orthogonal Frequency Division Multiplexing , Peak-to-Average Power Ratio, Selective level Mapping and Xilinx

[1] Mathuran Athan "Simulation of OFDM system in Matlab – BER Vs Eb/N0 for OFDM in AWGN channel" Gaussian Waves, http://www.gaussianwaves.com 2011/07/simulation-of-ofdm-system-in-matlab-ber-vs-ebn0-for-ofdm-in-awgn-channel/

[2] Zoha Pajoudi and Sied Hamidreza Jamali "Hardware Implementation of a 802.11n MIMO OFDM Transceiver", International Symposium on Telecommunications, 2008, pp. 414-419

[3] Yu Wei Lin and Chen Yi Lin, "Design of FFT/IFFT Processor for MIMO OFDM Systems", IEEE Transaction on circuit and system, vol. 54, no. 4, pp. 807-815, 2007

[4] Ashok Jhunjhunwala, "Next Generation wireless for rural areas", Indian Journal of Radio and Space Physics, vol. 36, pp. 165-167, 2007

[5] K. C. Chang and Gerald E. Sobelman "FPGA Based Design of a Pulsed-OFDM system," IEEE APCCAS ,2006, pp. 1128-1131

[6] N.V Irukrulapati,V.K Chakka and A. Jain "SLM based PAPR reduction of OFDM signal using new phase sequence",electronic letters, vol45 No24, 2009.

[7] V.Vijayarangam,R.Kalidoss, Dr.(Mrs)R.Sukanesh "LCM for PAPR Reduction in OFDM systems", ICWMMN Proceedings, 2006.

[8] N.V Irukulapati, V.KChakka and A.Jain "SLM based PAPR reduction of OFDM signal using new phase sequence" electronic letters, vol 45 No.24.

[9] Xiaowen Gu, Seungmin Baek, Suwon Park ,"PAPR Reduction of OFDM Signal Using an Efficient SLM Technique, 2007, LTE Solution Department, Shanghai Huawei Technologies Co., Ltd, Shanghai, China

[10] R. van Nee and A. deWild, "Reducing the peak to average power ratio of OFDM," in Proceedings of the 48th IEEE Semiannual Vehicular Technology Conference, May 1998, vol. 3, pp. 2072–2076.

Abstract: This paper presents an area-time efficient Coordinate Rotation Digital Computer (CORDIC) algorithm that completely eliminates the scale-factor. Besides we have proposed an algorithm to reduce the number of CORDIC iterations by increasing the number of stages. The efficient scale factor compensation techniques are proposed which adversely effect the latency/throughput of computation. The proposed CORDIC algorithm provides the flexibility to manipulate the number of iterations depending on the accuracy, area and latency requirements. The CORDIC is an iterative arithmetic algorithm for computing generalized vector rotations without performing multiplications.

Index Terms: coordinate rotation digital computer (CORDIC), cosine/sine, field-programmable gate array (FPGA), most-significant-1, recursive architecture, Discrete Fourier Transform (DFT), Discrete Cosine transform (DCT), Iterative CORDIC, Pipelined CORDIC.

[1] J. E. Volder, "The CORDIC trigonometric computing technique," IRE Trans. Electron. Comput. vol. EC-8, pp. 330–334, Sep. 1959.
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Process., vol. 81, pp. 1813–1822, 2001.
[3] P. K. Meher, J.Walls, T.-B.Juang, K. Sridharan, and K. Maharatna, "50 years of CORDIC: Algorithms, architectures and
applications," IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 56, no. 9, pp. 1893–1907, Sep. 2009.
[4] C. S. Wu and A. Y. Wu, "Modified vector rotational CORDIC (MVRCORDIC) algorithm and architecture," IEEE Trans. Circuits
Syst. II, Exp. Briefs, vol. 48, no. 6, pp. 548–561, Jun. 2001.
[5] C.-S.Wu, A.-Y.Wu, and C.-H. Lin, "A high-performance/low-latency vector rotational CORDIC architecture based on extended
elementary angle set and trellis-based searching schemes," IEEE Trans. Circuits Syst. II, Analog Digit. Signal Process, vol. 50, no.
9, pp. 589 601, Sep.2003.
[6] Y. H. Hu and S. Naganathan, "An angle recoding method for CORDIC algorithm implementation," IEEE Trans. Compute., vol. 42,
no. 1, pp. 99–102, Jan. 1993.
[7] M. G. B. Sumanasena, "A scale factor correction scheme for the CORDIC algorithm," IEEE Trans. Compute., vol. 57, no. 8, pp.
1148–1152, Aug. 2008.
[8] J. Villalba, T. Lang, and E. L. Zapata, "Parallel compensation of scale factor for the CORDIC algorithm," J. VLSI Signal Process.
Syst., vol. 19, no. 3, pp. 227–241, Aug. 1998.
[9] L. Vachhani, K. Sridharan, and P. K. Meher, "Efficient CORDIC algorithms and architectures for low area and high throughput
implementation," IEEE Trans. Circuit Syst. II, Exp. Briefs, vol. 56, no. 1, pp. 61–65,Jan. 2009.
[10] K. Maharatna, S. Banerjee, E. Grass, M. Krstic, and A. Troya, "Modified virtually scaling-free adaptive CORDIC rotator algorithm
and architecture,"IEEE Trans. Circuits Syst. Video Technol., vol. 11, no. 11,pp. 1463–1474, Nov. 2005.

Abstract: Inertial sensors, such as accelerometers and gyro-scopes, are rarely used by themselves to compute velocity and position as each requires the integration of very noisy data. The variance and bias in the resulting position and velocity estimates grow un-bounded in time. This paper proposes a solution to provide a de-biased and de-noised estimation of position and velocity of moving vehicle actions from accelerometer measurements. The method uses a continuous wavelet transform applied to the measurements recursively to provide reliable action trajectory reconstruction. The results are presented from experiments performed with a MEMS accelerometer and gyroscope.

Keywords: Action trajectory, continuous wavelet transform, inertial measurement unit.

[1] Kevin King, S.W. Yoon, N.C. Perkins, K. Najafi, "Wireless MEMS inertial sensor system for golf swing dynamics", Sensors and Actuators A: Physical, vol.141,2,2008.

[2] Tapus, Tapus, Mataric, " Userrobot personality matching and assistive robot behavior adaptation for poststroke rehabilitation therapy", Intelligent Service Robotics, vol. 1, issue.2, 2008.

3] Kelly, Saripalli, Sukhatme, "Combined Visual and Inertial Navigation for an Unmanned Aerial Vehicle," Field and Service Robotics, vol.42,2008 @

Abstract: The computer networks have evolved themselves into an altogether new generation with Mobile Ad-Hoc networks. The Mobile Ad-Hoc Networks are increasingly becoming more sophisticated and complex in terms of topology, routing and security[1][2][3]The new age MANETs incorporate routing of heavier traffic classes like audio, video and multimedia. It has become important to study the performance characteristics of the multimedia traffic class in MANETS [10] that includes packet loss rate and throughput. In this paper we will discuss these performance parameter throughput under different scenarios like varying Bandwidth, channel error rate, delay and fragment size.

Keywords: MANET, Packet loss rate, Throughput, Bandwidth, Fragment size

[1] S. P. Alampalayam, A. Kumar, and S. Srinivasan, ―Mobile ad hoc networks Security – a taxonomy,‖ in Proceedings of ICACT Conference, 2005, pp. 839-844.
[2] Naruephiphat, W, ―Routing Algorithm for Balancing Network Lifetime and Reliable Packet Delivery in Mobile Ad hoc Networks,‖ in ubiquitous, Autonomic and Trusted Computing, conference publications, 2009
[3] Nipun Sharma, ―ANALYSIS OF SECURITY REQUIREMENTS IN WIRELESS NETWORKS AND MOBILE AD-HOC NETWORKS‖ in GESJ: Computer Science and Telecommunications 2010| Vol No.5 (28) [4] Pankaj Rohal, Ruchika Dahiya, Prashant Dahiya, ― Study and Analysis of Throughput, Delay and Packet Delivery Ratio in MANET for Topology Based Routing Protocols (AODV, DSR and DSDV)‖ in international journal for advance research in engineering and technology Vol. 1, Issue II, Mar. 2013 ISSN 2320-6802
[5] http://en.wikipedia.org/wiki/Packet_loss
[6] Yi Lu Yuhui Zhong , ―Packet Loss in Mobile AdHoc Networks‖ Bharat Bhargava Purdue University, bb@cs.purdue.edu
[7] http://csie.nqu.edu.tw/smallko/ns2/measure.htm
[8] Network Simulator 2 — http://www.isi.edu/nsnam/ns/

[9] Dr. Nipun Sharma,Ms. Jasdeep Kaur , Ms. Jasmine Yadav , ― Implementation and Analysis of Fragmentation of MPEG-4 Traffic in NS-2 integrated with Evalvid‖ Oeconomics of Knowledge, Volume 5, Issue 2, Spring 2013.

[10] Vasos Vassiliou, Pavlos Antoniou, Iraklis Giannakos, and Andreas Pitsillides, "Requirements for the Transmission of Streaming Video in Mobile Wireless Networks‖

Abstract: The AMBA-AHB Multilayer Bus matrix Self-Motivated Arbitration scheme proposed three methods for data transmiting from master to slave for on chip communication. Multilayer advanced high-performance bus (ML-AHB) busmatrix employs slave-side arbitration. Slave-side arbitration is different from master-side arbitration in terms of request and grant signals since, in the former, the master merely starts a burst transaction and waits for the slave response to proceed to the next transfer. Therefore, in the former, the unit of arbitration can be a transaction or a transfer. However, the ML-AHB busmatrix of ARM offers only transfer-based fixed-pri-ority and round-robin arbitration schemes. In this paper, we propose the design and implementation of a flexible arbiter for the ML-AHB busmatrix to support three priority policies fixed priority, round robin, and dynamic priority and three data multiplexing modes transfer, transaction, and desired transfer length. In total, there are nine possible arbitration schemes. The proposed arbiter, which is self-motivated (SM), selects one of the nine possible arbitration schemes based upon the priority-level notifications and the desired transfer length from the masters so that arbitration leads to the maximum performance. Experimental results show that, although the area overhead of the proposed SM arbitration scheme is 9%–25% larger than those of the other arbitration schemes, our arbiter improves the throughput by 14%–62% compared to other schemes.

[1] M. Drinic, D. Kirovski, S. Megerian, and M. Potkonjak, "Latencyguided on-chip bus-network design," IEEE Trans. Comput.-Aided Design Integr. Circuits Syst., vol. 25, no. 12, pp. 2663–2673, Dec. 2006.

[2] S. Y. Hwang, K. S. Jhang, H. J. Park, Y. H. Bae, and H. J. Cho, "An ameliorated design method of ML-AHB busmatrix," ETRI J., vol. 28, no. 3, pp. 397–400, Jun. 2006.

[3] ARM, "AHB Example AMBA System," 2001 [Online]. Available: http://www.arm.com/products/solutions/AMBA_Spec.html

[4] IBM, New York, "32-bit Processor Local Bus Architecture Specification," 2001.
[5] R. Usselmann, "WISHBONE interconnect matrix IP core," Open- Cores, 2002. [Online]. Available: http://www.opencores.org/ ?do=project=wb_conmax

[6] N.-J. Kim and H.-J. Lee, "Design of AMBA wrappers for multipleclock operations," in Proc. Int. Conf. ICCCAS, Jun. 2004, vol. 2, pp. 1438–1442.

[7] D. Flynn, "AMBA: Enabling reusable on-chip designs," IEEE Micro, vol. 17, no. 4, pp. 20–27, Jul./Aug. 1997.slave-side arbitration schemes for the multi-layer AHB busmatrix," J. KISS, Comput. Syst. Theory, vol. 34, no. 5, pp. 257–266, Jun. 2007.

[9] S. S. Kallakuri and A. Doboli, "Customization of arbitration policies and buffer space distribution using continuous-time Markov decision processes," IEEE Trans. Very Large Scale Integr. (VLSI) Syst., vol. 15, no. 2, pp. 240–245, Feb. 2007.

[10] D. Seo and M. Thottethodi, "Table-lookup based crossbar arbitration for minimal-routed, 2D mesh and torus networks," in Proc. Int. Conf. IPDPS, Mar. 2007, pp. 1–10.

Abstract: In this thesis, we study the joint problems of cooperative link and diversity in A Mobile Ad-Hoc Network (MANET) with variable wireless channels. In MANET the wireless nodes are in group and infrastructure less in nature. The major problems faced by wireless communication in real time environment are that of interference and un-reliable communication links. Much research work has been done to overcome this by using various techniques. Cooperative communication and transmission side diversity in the network are the two of the techniques that help in reducing interference and communication link failures. We have also proposed a new technique to find the optimum route as a joint problem of the transmission power at the physical layer and the link selection at the network layer that incurs the minimum cost in terms of energy, no. of hops, available bandwidth and link quality (SNR), outage probability. Analytical results show that our cooperative transmission schemes (OMCTSP) achieves average energy saving of more than 80% than direct transmission.

Keywords: cooperative transmission, , channel gain, diversity, , linkcost minimum energy routing, outage diversity, Variable wireless channels.

[1] L. M. Feeney and M. Nilsson, "Investigating the energy consumption of a wireless network interface in an ad hoc networking environment," in Proc. INFOCOM 2001, Anchorage, AK, vol. 3, 2007, pp. 1548– 1557.

[2] J. H. Chang and L. Tassiulas, "Maximum lifetime routing in wireless sensor networks," IEEE/ACM Transactions on Networking, vol. 12, August 2004.

[3] C. K. Toh, "Maximum battery life routing to support ubiquitous mobile Computing in wireless ad hoc networks," IEEE Communications Magazine, 2001.

[4] J. Laneman and G. Wornell, "Distributed space-time coded protocols for exploiting cooperative diversity in wireless networks," IEEE Trans. Inform. Theory, vol. 49, no. 10, pp. 2415-2425, Oct. 2003.

[5] A. Nosratinia, T. Hunter, and A. Hedayat, "Cooperative communication in wireless networks," IEEE Communications Magazine, vol. 42, no. 10, pp. 74–80, Oct. 2004.

[6] A. Scaglione, D. L. Goeckel, and J. N. Laneman, "Cooperative communications in mobile ad-hoc networks: Rethinking the link abstraction,"

[7] J. N. Laneman, D. N. Tse, and G. W. Wornell, "Cooperative diversity in wireless networks: Efficient protocols and outage behavior," IEEE Trans. On Information Theory, vol. 50(12), Dec. 2004. IEEE Signal Processing Magazine, vol. 23, no. 5, pp. 15–19, Sep. 2006.

[8] J. E. Wieselthier, G. D. Nguyen, and A. Ephremides, "Algorithms for energy-efficient multicasting in ad hoc wireless networks," Mobile Netw. Appl., vol. 6, no. 3, pp. 251–263, Jun. 2001.

[9] S. M. Alamouti, "A simple transmit diversity technique for wireless communications," IEEE J. Sel. Areas Commun., vol. 16, no. 8, pp. 1451–1458, Oct. 1998.

[10] R. T. Derryberry, S. D. Gray, D. M. Ionescu, G. Mandyam, and B. Raghothaman, "Transmit diversity in 3G CDMA systems," IEEE Commun. Mag., vol. 40, no. 4, pp. 68–75, Apr. 2002

Abstract: With rapid growth in wireless Ad Hoc networks, Quality of service factor has drawn a great attention of researchers. Whereas network topology of wireless networks constantly changes, resources like bandwidth and energy are also limited. As power is very important factor for the proper working of Ad Hoc networks, need of the time is to research about efficient utilization of power. In the paper, we improve LAR (Location-Aided Routing), one of the most famous location based routing methods, which uses GPS technique to get information about the location of mobile node. Our new protocol considers both areas of routing and power. At first, propose a more efficient routing method which finds more stable paths .Secondly, a power aware method is proposed to have a prior knowledge about the remaining battery backups of all the intermediate nodes so that the nodes with battery backups equal to or greater than the minimum threshold power are the part of path between source and destination. This work presents an efficient approach for providing QOS in power aware scenario.

Keywords: Ad hoc networks, Average power, Expected Zone, Requested Zone, Threshold power

[1] D. D. Perkins and H. D. Hughes, "A survey on quality-of-service support for mobile ad hoc networks," Wireless Communications and Mobile Computing, 2002

[2] G. Dommety and R. Jain. "Potential Networking Applications of Global Positioning System (GPS)," Technical Report TR-24, Computer Science Department, The Ohio State University, April 1999

[3] Jangsu Lee, Seunghwan Y00, and Sungchun Kim," Energy aware Routing in Location based Ad-hoc Networks", Proceedings of the 4th International Symposium on Communications, Control and Signal Processing, ISCCSP 2010, Limassol, Cyprus, 3-5 March 2010

[4] Mohammad A. Mikki," Energy Efficient Location Aided Routing Protocol for Wireless MANETs", (IJCSIS) International Journal of Computer Science and Information Security Vol. 4, No. 1 & 2, 2009

[5] P.K.Suri Dr. M. K. Soni, Mrs. Parul Tomar" Location Based Power Aware Routing"

[6] Pramita M, Christian P and Shivajit M" Stability Aware Routing: Exploiting Transient Route Availability in MANETs Proceeding HPCC'07 Proceedings of the Third international conference on High Performance Computing and Communications Pages 508-520, Springer-Verlag Berlin, Heidelberg ©2007

[7] Tzay-Farn Shih , Hsu-Chun Yen, "Location-aware routing protocol with dynamic adaptation of request zone for mobile ad hoc networks", Springer Wireless Netw (2008) 14:321–333,DOI 10.1007/s11276-006-9955-y

[8] Wenzhu Zhang, Jiandong Li and Xuan Wang, "Cost-Efficient QoS Routing Protocol for Mobile Ad Hoc Networks", Proceedings of the 19th International Conference on Advanced Information Networking and Applications (AINA'05).

[9] Y.B. Ko and N. H. Vaidya, "Location-Aided Routing in Mobile Ad Hoc-Scale for Ad Hoc Networks," Proceedings of the second ACM international symposium on Mobile ad hoc networking & computing, Long Beach, CA, USA, pp. 22-32, October 2001

Abstract: An audio mixer amplifier is a device that translates a signal of one frequency band to another. It will accept many inputs at different frequencies and generate an output of the combination or sum of the frequencies. The mixer circuit provides good gain to weak audio signals. It can be used in front of an R.F. oscillator to make an R.F. receiver that is very sensitive to sound. Each input can be independently controlled by a variable resistor. There is also a provision for a balance control to fade out signal while simultaneously fading in the other.

Key Words: Audio Mixer, Frequency, Signal, Circuit.

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[4]. Marki F. andMarki C., (2010): Mixer Basics Primer, A Tutorial for RF& Microwave Mixers,Marki Microwave, Inc.
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