The sub-threshold and gate leakage power consumption in deep submicron CMOS systems are projected to become a significant part of the total power dissipation. This paper presents several dual-threshold voltage techniques for reducing standby power dissipation while still maintaining high performance. A dual-mode logic gate, for selectable operation in either of static and dynamic modes, includes: a static gate which includes at least one logic input and a logic output; a mode selector, configured for outputting a turn-off signal to select static mode operation and for outputting a dynamic clock signal to select dynamic mode operation and a switching element associated with the mode selector static gate, comprising a first input connected to a constant voltage, a second input for inputting the mode selection signal from the mode selector, and an output connected to a logic output of the static gate. The switching elements switches the logic gate operation from static to dynamic mode, by applying the appropriate signal to the switching element. As transistor sizes scale down and levels of integration increase, leakage power has become a critical problem in VLSI designs. In this paper, an industry-standard technique known as power-gating is explored, whereby transistors are used to disconnect the power from idle portions of a chip.This paper discusses the evolution of full adder circuits in terms of lesser power consumption high speed. The power gating techniques are implemented to design a full adder by reducing the number of transistors which also leads to the reduction of chip size.

 

Keywords: Dual Mode Logic, Sub-threshold, Power Gating

[1] B. H. Calhoun, A. Wang, and A. Chandrakasan, "Modeling and sizing for minimum energy operation in subthreshold circuits," IEEE J. Solid-State Circuits, vol. 40, no. 9, pp. 1778–1786, Sep.2005.

[2] N. Geetha Rani, N. Praveen Kumar, Dr. B. Dr. B. Stephen Charles, Dr. P. Chandrasekhar Reddy S.Md.Imran Ali , "Design of Near-Threshold CMOS Logic Gates", IJVLSICS Vol.3, No.2, April 2012.

[3] Branko L. Dokić, "A Review on Energy Efficient CMOS Digital Logic," ETASR - Engineering, Technology & Applied Science Research, Vol. 3, o. 6, 2013, 552-561.

[4] PriyaGupta, AnuGupta, AbhijitAsati, "A Review on Ultra Low Power Design Technique :Subthreshold Logic," IJCST Vol. 4, Issue Spl - 2, April - June 2013.

[5] JagannathSamanta, MousamHalder, Bishnu Prasad De, "Performance Analysis of High Speed Low Power Carry Look-Ahead Adder Using Different Logic Styles" International Journal of Soft Computing and Engineering (IJSCE) ISSN:2231-2307, Volume-2, Issue-6, Jan-2013.

This paper concerned with basic concepts and some results on (idempotent) semigroup satisfying the identities of three variables. The motivation of taking three for the number of variables has come from the fact that many important identities on idempotent semigroups are written by three or fewer independent variables. We consider the semigroup satisfying the property abc = ac and prove that it is left semi- normal and right quasi-normal. Again an idempotent semigroup with an identity aba = ab and aba = ba (ab = a, ab = b) is always a semilattices and normal. An idempotent semigroup is normal if and only if it is both left quasi-normal and right quasi-normal. If a semigroup is rectangular then it is left and right semi-regular.

[1]. A.H.Clifford and G.B.Preston :"The algebraic theory of semigroups" Math.surveys7; vol .I Amer.math. soc 1961.
[2]. David.McLean "idempotent semigroups" Amer.math.monthly; 61;110-113.
[3]. J.M.Howie " An introduction to semigroup theory" Academic Press (1976).
[4]. Miyuki Yamada and Naoki Kimura " Note on idempotent semigroups.II" Proc.Japan Acad. 34;110 (1958).
[5]. Naoki.Kimura "The structure of idempotent semigroups(1) Proc.Japan.Acad., 33,(1957) P.642.

In this paper direct-coupled solar energy powered multicore architectures that provide direct power supply between photovoltaic (PV) generation and the load without the adoption of battery. We present Solar-Tune, a real-time scheduling technique with load tuning for sporadic tasks on solar energy powered multicore systems. The objective is to fully utilize the available solar energy while meeting the deadlines of tasks. Scheduling and power management method for multicore real-time embedded systems. This work mathematically proves that by allocating the new task to the core with the lowest utilization, we can achieve the lowest overall energy dissipation. This method, combined with a new integer linear programming (ILP) algorithm with forms the heuristic algorithm to dynamically refine the task scheduling based on the predictions of the availability of solar energy. With periodical tasks in a multi-core platform, this partitioned scheduling method is optimal for energy dissipation if the proposed utilization based scheduling and ILP algorithm is applied on each core. Experimental results show that new algorithm achieves better performance in terms of deadline miss rate, comparing to the best of existing algorithm. When applied on a multi-core platform, the heuristic algorithm achieves better efficiency.

 

Keywords: Photo Voltaic, ILP, Solar Tune, MPPT

[1] Yi Wang, Renhai Chen, Zili Shao, Tao Li."Solar tune: Real-time Scheduling With Load Tuning For Solar Energy Powered Multicore Systems".IEEE International Conference OnEmbedded And Real-time Systems And Applications,2013.

[2] A. Abbas, E. Grolleau, M. LOUDINI, And D. Mehdi. "A Real-time Feedback Scheduler For Environmental Energy Harvesting". International Conference On Systems And Control,Algiers, Algeria, October 29-31, 2013.

[3] ManishBhardwaj, SubharmanyaBharathi, BilalAkin."Controlling And Monitoring Solar Energy Production In The Smart Grid Using Heterogeneous Dual Core MCU". 978-1-4577-1216-6/2012 IEEE.

[4] A.Kassem (IEEE Member)And M. Hamad (IEEE Member). "A Microcontroller-based Multi-function Solar Tracking System", 2011 IEEE.

[5] CesareAlippi, Fellow, IEEE, AndCristianGalperti."An Adaptive System ForOptimal Solar Energy Harvesting In Wireless Sensor Network Nodes", IEEETransactions On Circuits AndSystems—i: Regular Papers, Vol. 55, No. 6, July 2008

In order to measure the core porosity quickly and accurately, the article from the principle to the experimental procedure describes two simple measurement methods: gas measurement method and weighing method. Gas measurement method to measure the core porosity is by checking the gas pressure changes before and after the gas into the core to determine the core porosity; weighing method to measure the core porosity is by measuring the core dry weight, wet weight, and buoyant weight to calculate the porosity. Comparative analysis of the advantages and disadvantages of the two methods, and obtained data is compared with the core porosity data as standard values PE-02 nuclear magnetic resonance core analyzer have measured, final conclusion: gas measurement method and weighing method to measure the core porosity, experimental operation convenient, measurement error is small, in the porosity measurement process integrate the two ways to obtain accurate porosity values.

 

Key Words: porosity; gas measurement method; weighing method

[1] Zhenggang Pu. Measurement of Core Porosity and Error Analysis [J]. Chemical Engineering of Oil and Gas, 1996, 03:153-155+181.

[2] Shijun Zhao, Rongting Ren, Shaoguo Ma. Study on Measurement of Core Porosity Based on Linear Fitting [J]. PETROLEUM INSTRUMENTS, 1997, 04:10-11+62.

[3] Zhenbao Ling, Debao Zou, Kun Zhang, Min Xu, Jun Wang. Investigation on Measuring Methodology of Rock and Ore Sample Porosity [J]. Journal of Jilin University (Earth Science Edition), 2011, 03:921-924.

[4] Xiaowen Wang, Lizhi Xiao, Ranhong xie, Yuanzhong Zhang. Chinese terrestrial formation NMR porosity study [J]. Science in China (Series G: Physics, Mechanics & Astronomy), 2006, 04:366-374.

[5] Zhongdong Wang, Hao Wang, Nenggen Li, Longhai Qiao. Analysis of Core NMR Data from Laboratory Measurements [J]. Well Logging Technology, 2001, 03:170-174.

Though there exists a variety of amplifier specifications for various purposes, most of the amplifiers are designed to work in a lower frequency band, and those that work in higher frequencies are optimized for higher efficiency and not for linearity. This paper describes the approach to design and simulate a Class A small signal Linear Amplifier that works in C Band. The bias network, matching network and the cascaded amplifier stages of the system are designed and simulated. The simulation yields the values of the S parameters and the resulting gain. The system is expected to provide a gain of 30dB and work in a frequency range of 5-6 GHz of the C band.

 

Index Terms: - C Band, Linear Amplifier, S parameters

[1] Muhammad Faheem Siddique, Syed Haider Abbas, HussnainHaider, and Ali Bin Tahir,"Design and Simulation of Cascaded Class-A Microwave Power Amplifier", International Journal of Electrical and Computer Engineering (IJECE), Vol. 3, No. 5, pp. 635~639, October 2013.
[2] P.Raj Kumar, "Design of L-Band Low noise Amplifier", Study phase report, unpublished.
[3] Chen Yifeng, QuanJinhai, Liu Yungang, Hu Liulin , "A 6–18 GHz broadband power amplifier MMIC with excellent efficiency", Journal of Semiconductors, Vol. 35, No. 1, January 2014 Sanggeun Jeon, , Yu-Jiu Wang, Hua Wang,Florian Bohn, IEEE, Arun Natarajan, Aydin Babakhani, Ali Hajimiri, ,"A Scalable 6-to-18 GHz Concurrent Dual-Band Quad-Beam Phased-Array Receiver in CMOS",IEEE Journal of Solid State Circuits , Vol. 43, No. 12, December 2008.
[4] Agilent Technologies. (2011). Advanced Design System (ADS) 2011.10 with Momentum planar EM simulator, Santa Clara, CA. [Online]. Available: http://www.agilent.com

[5] A. Raghunathan, P. Raj kumar, N. Udayashankar, and K.J. Vinoy, "Ultra wide band low noise amplifier for low frequency applications in radio astronomy", Accepted for URSI General Meeting, Chicago, IL USA August 7-16, 2008

Conventional resources of energy are limited & are non-renewable & looking at today's rate of consumption these resources are going to get exhausted in some years. This possibility of exhaustion is called energy crisis. The world is clearly running out of oil and gas, yet most people ignore the coming crisis. Food production and distribution in the industrialized world have become so dependent on petroleum use it's hard to imagine how Agriculture will function without this fuel. Solar energy could supply all the present and future energy needs of the world on a continuing basis. This makes it one of the most promising of the unconventional energy sources. Hence a Solar powered robot for agriculture means simple eco-friendly Agricultural Robot.

 

Keywords: - AT89c51, Tracking &Trapping,L293D, Wireless, Trace & Retrace, sensors, DC motors.

[1] Texas Instruments – RFID support http://www.ti.com/tiris/default.htm
[2] RFID Forum http://www.rfidtalk.com/
[3] All data sheet - Datasheet search site for Electronic Components http://www.alldatasheet.com/
[4] AT89S51 MCUs overview http://www.atmel.com/dyn/general/tech_doc.asp?doc_id=7190
[5] Voice module: APR9600http://www.intec-group.co.uk/Datasheet/APR9600.PDF
[6] Sirit Technologies http://www.sirit.com/default.asp?sectionID=2&action=open&pageID=7

This section deals with the applications of semigroups in general and regular semigroups in particular. The theory of semigroups attracts many algebraists due to their applications to automata theory, formal languages, network analogy etc. In section 2 we have seen different areas of applications of semigroups. We identified some examples in biology, sociology etc. whose semigroup structures are nothing but regular, E-inversive and inverse semigroup etc.

[1] Arbib,M.A. "Algebraic theory of machines, Languages and Semigroups" New york (1968), Academic Press.
[2] Arbib,M.A. "Theories of Abstract Automata", Englewood Cliffs, N.J.: Prentice Hall.(1969)
[3] Boorman, S.A. and White, H.C. "Social structures from multiple networks-II: role Structures." Amer.J.Sociol.81(1976), 1384-1466.
[4] Boyd, J.P., Haehl,J.H. and Sailer,L.D. "Kinship Systems and Inverse semigroups", J.Math.Sociol.76,(1972), 37-61.
[5] Clifford, A.H. and Preston, G.B. "The algebraic theory of semigroups", Math.Surveys No.7,Amer.math.soc., Vol. I, (1967).

This paper presents the results of a study to develop a fast calculation routine which enables the prediction of the frost layer growth and the deposition velocity in terms of the surface temperature of the cold body, the rate of flow of the humid air and the rate of flow heat transfer and mass transfer equation for the flow of wet air around a circular cylinder are formulated and solved and the results are presented in function of the surface temperature, mass flow rate of the humid air and the mass flow rate of the working fluid. In order to validate the model and the numerical predictions, an experimental rig is constructed and adequately instrumented. Experiments were realized and the results were composed with the numerical predictions to confirm the validity of the model.

 

Keywords- Frost; Frost predictions, Frost thickness; modeling of frost; measurements of frost

[1] Stoecker WF. How the formation on coils affects refrigeration systems. Refrigerating Engineering 1957; 65 (2):42-46.

[2] Niederer DH. Defrosting of air units in central systems. ASHRAE Transactions. (1976)

[3] Chung PM, Algren AB. Frost formation and heat transfer on a cylinder surface in humid air cross flow. Heating piping and air conditioning 1958: (1) 171-178.

[4] Yonko JD, Sepsy CF. An investigation of the thermal conductivity of frost while forming on a fiat horizontal plate. ASHRAE Transaction 1967; 73: 1-10.

[5] Shah YT. Theory of frost formation. Ph.D. thesis, MIT 1969.

Gas Turbine power plants are widely applied for power generation in Nigeria. Due to the geographical location of Nigeria, the international organization for standardization, ISO conditions of 15oC and relative humidity of 60% for an ideal GT operation rarely occur. This variance of the environmental temperature results to drop in thermal efficiency and power output of the power plants. One of the most important ways of improving the performance of GT is the application of GT inlet cooling technology where the temperature of the air entering the compressor is brought lower than the prevailing ambient temperature. This paper, therefore, presents the results of the study of the thermal analysis and the economic benefits derived from the incorporation of an evaporative cooling technique in a Rolls Royce, Industrial Olympus-SK 30 GT plant located at Imiringi, Southern Nigeria. Data generated from the power station were used for both the thermal and economic analysis. The analysis shows that reducing the plant inlet temperature by 2oC could lead to power gain of 2.02MW and increase of plant efficiency from 21.76% to 21.90%. The economic analysis also indicates that the total saving resulting from the application of the evaporative cooling depends on the power gained which is evident in the years 2004 when the power gain was 2.02MW with total saving resulting from cooling of US$21136.76 . However, in terms of the net profit and the fuel saving per annum, the plant seems to show a loss in profit owing to the low power being generated by it but the economic viability would be seen in the long run with the fact that the higher the power output, the greater the fuel saving per annum.

 

Keywords: Power Gained, Thermal Efficiency, Dry Bulb Temperature, Evaporative Cooling, Net Profit, Total Saving, Gas Turbine, Psychometric Chart

[1] Agba, A.M.O, Ikoh, M.U. and Usie, E.M. (2013). Developing the Niger Delta Region of Nigeria Through Community Development Committees (CDCs): A Critical Assessment. International Journal of Public Administration and Management Research (IJPAMR), Vol. 2, No. I, pp. 130-142 [2] Odjugo, P. A. O. (2011). Perception of Climate Change in the Niger Delta Area of Nigeria. In A. G. Onorkerhoraye (Ed.), Centre for Population and Environmental Development Policy Paper Series (pp. 1-14). Benin: Centre for Population and Environmental Development.
[3] Oyedepo, S.O, Fagbenle, R.O., Adefila, S. S. and Adavbiele, S. A. (2014). Performance Evaluation and Economic Analysis of a Gas Turbine Power plant in Nigeria. Retrieved 25 July, 2014 from the World Wide Web: www.elsevier.com/locate/enconman
[4] Omidvar, B. (2001). Gas Turbine inlet Cooling System. Retrieved 7 January, 2014 from the World Wide Web: http://www.albadronline.com/oldsite/books/49_GasTurbineInlet.pdf

[5] Ogbonnaya, E. A. (2004). Thermodynamics of Steam and Gas Turbine, Oru's Press Ltd, Port Harcourt, pp. 68-71.