| Abstract: | This paper discusses the properties of rice husk ash samples produced from different types of field ovens to compare the performance of the ovens and to identify the most feasible method to produce a reactive pozzolana as an alternative to cement for building applications requiring lower strengths. Different types of ashes are produced and long-term strength of rice husk ash pozzolanas with lime or cement is investigated to suggest a sustainable affordable option in rural building applications, especially for rural housing in Kerala, a southern state of India |
| Description: | Cement and Concrete Research 36 (2006) 1062–1071 |
| URI: | http://dyuthi.cusat.ac.in/purl/4642 |
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| Reactive pozzol ... ment for rural housing.pdf | (331.9Kb) |
| Abstract: | This study examines the behavioral factors that influence the Indian Investors to invest in the Real Estate Market. Among the various factors that affect the tendency of investors to invest in the real market, certain factors are greatly influenced the investors at greatest extend while others at least level. From this study it is revealed that motivation from the real estate developers and brokers (mean value- 3.46) is most influencing factor and happening of uncertain events (mean value- 1.75) is the least factor that influences the investors’ investment behavior. In this study, the behavioral factor like over confidence and the hypotheses regarding education, religion were analyzed and found that religious factor influences the Indian investors to invest in the real estate |
| Description: | SSIJEM VOLUME 3, ISSUE 2 [MARCH 2013] |
| URI: | http://dyuthi.cusat.ac.in/purl/4585 |
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| Real Estate Dev ... mpirical Investigation.pdf | (450.3Kb) |
| Abstract: | This paper introduces a simple and efficient method and its implementation in an FPGA for reducing the odometric localization errors caused by over count readings of an optical encoder based odometric system in a mobile robot due to wheel-slippage and terrain irregularities. The detection and correction is based on redundant encoder measurements. The method suggested relies on the fact that the wheel slippage or terrain irregularities cause more count readings from the encoder than what corresponds to the actual distance travelled by the vehicle. The standard quadrature technique is used to obtain four counts in each encoder period. In this work a three-wheeled mobile robot vehicle with one driving-steering wheel and two-fixed rear wheels in-axis, fitted with incremental optical encoders is considered. The CORDIC algorithm has been used for the computation of sine and cosine terms in the update equations. The results presented demonstrate the effectiveness of the technique |
| Description: | Journal of Automation, Mobile Robotics & Intelligent Systems VOLUME 3, No 3 2009 |
| URI: | http://dyuthi.cusat.ac.in/purl/4474 |
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| A Realization O ... Wheeled Mobile Robots.pdf | (1.110Mb) |
| Abstract: | A sensitive method based on the principle of photothermal phenomena to realize optical logic gates is presented. A dual beam thermal lens method using low power cw lasers in a dye-doped polymer can be very effectively used as an alternate technique to perform the logical function such as NAND, AND and OR. |
| URI: | http://dyuthi.cusat.ac.in/purl/2412 |
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| Dyuthi-P0241.pdf | (99.53Kb) |
| Abstract: | The greatest damage inflicted by the recent recession has not necessarily been financial but emotional and psychological. There are a lot of direct and indirect societal challenges ,changes and oppurtunuties that were brought by recession everywhere including in India. In this paper an attempt is made to analyse such societal changes challenges and oppurtunities. |
| Description: | Holy Grace Management Review vol.3 no.1 Dec 2011 |
| URI: | http://dyuthi.cusat.ac.in/purl/4293 |
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| Recession-induc ... nges and Opportunities.pdf | (391.2Kb) |
| Abstract: | A novel reconfigurable, single feed, dual frequency, dualpolarized operation of a hexagonal slot-loaded square mwrostrip antenna is presented in this paper. A pin diode incorporated in the slot is used to switch the two operating frequencies considerably, without significantly affecting the radiation characteristics and gain. The proposed antenna provides a size reduction up to 61% and 26% Jor the two resonating frequencies, compared to standard rectangular patches. This design also gives considerable bandwidth up to 3.3% and 4.27%, for the two frequencies with a low operating frequency ratio |
| URI: | http://dyuthi.cusat.ac.in/purl/1420 |
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| A reconfigurati ... ntrolled by pin diodes.PDF | (1.097Mb) |
| Abstract: | Plane-wave transmission gratings were stored in the same location of silver- doped photopolymer ¯lm using peristrophic multiplexing techniques. Constant and vari- able exposure scheduling methods were adopted for storing gratings in the ¯lm using He{Ne laser (632.8 nm). The role of recording geometry on the dynamic range of the ma- terial was studied by comparing the results obtained from both techniques. Peristrophic multiplexing with rotation of the ¯lm in a plane normal to the bisector of the incident beams resulted in better homogenization of di®raction e±ciencies and larger M/# value. |
| Description: | Pramana { J. Phys., Vol. 75, No. 6, December 2010 |
| URI: | http://dyuthi.cusat.ac.in/purl/4013 |
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| Recording multi ... istrophic multiplexing.pdf | (389.8Kb) |
| Abstract: | Experimental investigations on Microstrip line excited Dielectric Resonator Antenna configurations suitable for Mobile Communication applications are reported. High permittivity (εrd = 48) resonator samples with different aspect ratios are employed for the study. Theoretical analysis performed using FDTD method is also presented. |
| Description: | XXVIII URSI GA New Delhi |
| URI: | http://dyuthi.cusat.ac.in/purl/4327 |
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| Rectangular Die ... unication Applications.pdf | (440.1Kb) |
| Abstract: | In this paper, we present an effective excitation of a reelangular dielectric resonator antennas (DRA) with a conductor-hacked coplanar waveguide (CB-CPW). The radiation and resonance characteristics are found to van,, depending on the orientation of the DR on doe coplanar feed line. The effect of finite and infinite ground planes of CB-CPIV on the radiation characteristics of the rectangular DRA is studied. The orientation and position of the DR are optimized for maximum gain and bandwidth. The optimized antenna ,geometry offers --10.46 dBi gain and 7.5% bandwidth with low cross-polar radiation characteristics |
| URI: | http://dyuthi.cusat.ac.in/purl/1426 |
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| Rectangular die ... uctor-backed co-planar.PDF | (1.069Mb) |
| Abstract: | It is observed that reclamation of natural rubber latex based rubber using 2,2'-dibenzamidodiphenvldisulphide as reclaiming agent is an optional methodology for recycling of waste latex rubber (WLR). For progressive replacement of virgin natural rubber by the reclaim, two alternatives curing system were investigated: adjustment or reduction of the curing system with increasing reclaim content, to compensate for the extra amount of curatives brought along by the reclaim. For fixed curing system, as if the reclaim were equivalent to virgin NR. The cure behavior, final crosslink density and distribution, mechanical properties, and dynamic viscoelastic properties of the blends with reclaimed WLR are measured and compared with the virgin compound. The morphology of the blends, sulfur migration, and final distribution are analyzed.The mechanical and dynamic viscoelastic properties deteriorate for both curing systems, but to a lesser extent for fixed curing system compared to adjusted curing system. With the fixed cure system, many properties like tensile strength and compression set do still deteriorate, but tan 6 and Mrrr„/Murxr, representative for the rolling resistance of tires are improved. On the other hand, with the adjusted cure system both mechanical and dynamic properties still deteriorate. |
| URI: | http://dyuthi.cusat.ac.in/purl/820 |
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| V V Rajan and o ... cling of NR...,Feb2006.PDF | (9.335Mb) |
| Abstract: | A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first 10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure indicat- ing their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles are carbon and oxygen. Strangely, a test for DNA using Ethidium Bromide dye fluorescence technique indicates absence of DNA in these cells. In the context of a suspected link between a meteor airburst event and the red rain, the possibility for the extraterrestrial origin of these particles from cometary fragments is discussed. |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/1976 |
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| Red rain phenomenon of Kerala.pdf | (412.3Kb) |
| Abstract: | We propose antimicrobial photodynamic therapy (aPDT) as an alternative strategy to reduce the use of antibiotics in shrimp larviculture systems. The growth of a multiple antibiotic resistant Vibrio harveyi strain was effectively controlled by treating the cells with Rose Bengal and photosensitizing for 30 min using a halogen lamp. This resulted in the death of > 50% of the cells within the first 10 min of exposure and the 50% reduction in the cell wall integrity after 30 min could be attributed to the destruction of outer membrane protein of V. harveyi by reactive oxygen intermediates produced during the photosensitization. Further, mesocosm experiments with V. harveyi and Artemia nauplii demonstrated that in 30 min, the aPDT could kill 78.9% and 91.2% of heterotrophic bacterial and Vibrio population respectively. In conclusion, the study demonstrated that aPDT with its rapid action and as yet unreported resistance development possibilities could be a propitious strategy to reduce the use of antibiotics in shrimp larviculture systems and thereby, avoid their hazardous effects on human health and the ecosystem at large. |
| Description: | Microbial Biotechnology (2012) 5(1), 59–68 |
| URI: | http://dyuthi.cusat.ac.in/purl/4072 |
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| Reducing Vibrio ... in shrimp larviculture.pdf | (1.392Mb) |
| Abstract: | The Towed Array electronics is a multi-channel simultaneous real time high speed data acquisition system. Since its assembly is highly manpower intensive, the costs of arrays are prohibitive and therefore any attempt to reduce the manufacturing, assembly, testing and maintenance costs is a welcome proposition. The Network Based Towed Array is an innovative concept and its implementation has remarkably simplified the fabrication, assembly and testing and revolutionised the Towed Array scenario. The focus of this paper is to give a good insight into the Reliability aspects of Network Based Towed Array. A case study of the comparison between the conventional array and the network based towed array is also dealt with |
| Description: | Ocean Electronics (SYMPOL), 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/4497 |
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| Re-Engineering ... work Based Towed Array.pdf | (639.1Kb) |
| Abstract: | Regional climate models are becoming increasingly popular to provide high resolution climate change information for impacts assessments to inform adaptation options. Many countries and provinces requiring these assessments are as small as 200,000 km2 in size, significantly smaller than an ideal domain needed for successful applications of one-way nested regional climate models. Therefore assessments on sub-regional scales (e.g., river basins) are generally carried out using climate change simulations performed for relatively larger regions. Here we show that the seasonal mean hydrological cycle and the day-to-day precipitation variations of a sub-region within the model domain are sensitive to the domain size, even though the large scale circulation features over the region are largely insensitive. On seasonal timescales, the relatively smaller domains intensify the hydrological cycle by increasing the net transport of moisture into the study region and thereby enhancing the precipitation and local recycling of moisture. On daily timescales, the simulations run over smaller domains produce higher number of moderate precipitation days in the sub-region relative to the corresponding larger domain simulations. An assessment of daily variations of water vapor and the vertical velocity within the sub-region indicates that the smaller domains may favor more frequent moderate uplifting and subsequent precipitation in the region. The results remained largely insensitive to the horizontal resolution of the model, indicating the robustness of the domain size influence on the regional model solutions. These domain size dependent precipitation characteristics have the potential to add one more level of uncertainty to the downscaled projections. |
| Description: | JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, D10113, doi:10.1029/2012JD017956, 2012 |
| URI: | http://dyuthi.cusat.ac.in/purl/4119 |
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| Regional climat ... ownscaling uncertainty.pdf | (1.497Mb) |
| Abstract: | Reinforcement Learning (RL) refers to a class of learning algorithms in which learning system learns which action to take in different situations by using a scalar evaluation received from the environment on performing an action. RL has been successfully applied to many multi stage decision making problem (MDP) where in each stage the learning systems decides which action has to be taken. Economic Dispatch (ED) problem is an important scheduling problem in power systems, which decides the amount of generation to be allocated to each generating unit so that the total cost of generation is minimized without violating system constraints. In this paper we formulate economic dispatch problem as a multi stage decision making problem. In this paper, we also develop RL based algorithm to solve the ED problem. The performance of our algorithm is compared with other recent methods. The main advantage of our method is it can learn the schedule for all possible demands simultaneously. |
| Description: | TENCON 2008-2008 IEEE Region 10 Conference |
| URI: | http://dyuthi.cusat.ac.in/purl/4480 |
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| A Reinforcement ... ng Transmission Losses.pdf | (265.1Kb) |
| Abstract: | This paper presents Reinforcement Learning (RL) approaches to Economic Dispatch problem. In this paper, formulation of Economic Dispatch as a multi stage decision making problem is carried out, then two variants of RL algorithms are presented. A third algorithm which takes into consideration the transmission losses is also explained. Efficiency and flexibility of the proposed algorithms are demonstrated through different representative systems: a three generator system with given generation cost table, IEEE 30 bus system with quadratic cost functions, 10 generator system having piecewise quadratic cost functions and a 20 generator system considering transmission losses. A comparison of the computation times of different algorithms is also carried out. |
| Description: | Electrical Power and Energy Systems 33 (2011) 836–845 |
| URI: | http://dyuthi.cusat.ac.in/purl/4484 |
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| Reinforcement L ... nomic Dispatch problem.pdf | (311.8Kb) |
| Abstract: | This paper presents a Reinforcement Learning (RL) approach to economic dispatch (ED) using Radial Basis Function neural network. We formulate the ED as an N stage decision making problem. We propose a novel architecture to store Qvalues and present a learning algorithm to learn the weights of the neural network. Even though many stochastic search techniques like simulated annealing, genetic algorithm and evolutionary programming have been applied to ED, they require searching for the optimal solution for each load demand. Also they find limitation in handling stochastic cost functions. In our approach once we learn the Q-values, we can find the dispatch for any load demand. We have recently proposed a RL approach to ED. In that approach, we could find only the optimum dispatch for a set of specified discrete values of power demand. The performance of the proposed algorithm is validated by taking IEEE 6 bus system, considering transmission losses |
| Description: | Fifteenth National Power Systems Conference (NPSC), IIT Bombay, December 2008 |
| URI: | http://dyuthi.cusat.ac.in/purl/4490 |
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| A Reinforcement ... using Neural Networks.pdf | (165.9Kb) |
| Abstract: | Unit Commitment Problem (UCP) in power system refers to the problem of determining the on/ off status of generating units that minimize the operating cost during a given time horizon. Since various system and generation constraints are to be satisfied while finding the optimum schedule, UCP turns to be a constrained optimization problem in power system scheduling. Numerical solutions developed are limited for small systems and heuristic methodologies find difficulty in handling stochastic cost functions associated with practical systems. This paper models Unit Commitment as a multi stage decision making task and an efficient Reinforcement Learning solution is formulated considering minimum up time /down time constraints. The correctness and efficiency of the developed solutions are verified for standard test systems |
| Description: | International J. of Recent Trends in Engineering and Technology, Vol. 3, No. 3, May 2010 |
| URI: | http://dyuthi.cusat.ac.in/purl/4489 |
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| Reinforcement L ... through pursuit method.pdf | (568.2Kb) |
| Abstract: | Unit commitment is an optimization task in electric power generation control sector. It involves scheduling the ON/OFF status of the generating units to meet the load demand with minimum generation cost satisfying the different constraints existing in the system. Numerical solutions developed are limited for small systems and heuristic methodologies find difficulty in handling stochastic cost functions associated with practical systems. This paper models Unit Commitment as a multi stage decision task and Reinforcement Learning solution is formulated through one efficient exploration strategy: Pursuit method. The correctness and efficiency of the developed solutions are verified for standard test systems |
| Description: | Advances in Computing, Control, & Telecommunication Technologies, 2009. ACT'09. International Conference on |
| URI: | http://dyuthi.cusat.ac.in/purl/4494 |
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| Reinforcement L ... through pursuit method.pdf | (300.8Kb) |
| Abstract: | Microcosm studies have been carried out to find out the relative survival of Escherichia coli and Salmonella typhimurium in a tropical estuary. Survival has been assessed in relation to the important self-purifying parameters such as biotic factors contained in the estuarine water, toxicity due to the dissolved organic and antibiotic substances in the water and the sunlight. The results revealed that sunlight is the most important inactivating factor on the survival of E. coli and S. typhimurium in the estuarine water. While the biological factors contained in the estuarine water such as protozoans and bacteriophages also exerted considerable inactivation of these organisms, the composition of the water with all its dissolved organic and inorganic substances was not damaging to the test organisms. Results also indicated better survival capacity of E. coli cells under all test conditions when compared to S. typhimurium |
| Description: | Water Research |
| URI: | http://dyuthi.cusat.ac.in/purl/3961 |
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| Relative surviv ... in a tropical estuary.pdf | (221.5Kb) |
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