| Abstract: | A technique for improving the coupling between a feed horn and reflector by using corrugated metallic flanges is presented. Experimental data for flanges of varying parameters are given and theoretical explanation is supplemented |
| URI: | http://dyuthi.cusat.ac.in/purl/1430 |
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| Corrugated flan ... araboloidal reflectors.PDF | (1.323Mb) |
| Abstract: | The need for improved feed systems for large reflector antennas employed in Radio Astronomy and Satellite tracking spurred the interest in horn antenna research in the 1960's. The major requirements were to reduce spill over, cross-polarisation losses,and to enhance the aperture efficiency to the order of about 75-8O%L The search for such a feed culminated in the corrugated horn. The corrugat1e 1 horn triggered widespread interest and enthusiasm, and a large amount of work(32’34’49’5O’52’53’58’65’75’79)has already been done on this type of antennas. The properties of corrugated surfaces has been investigated in detail. It was strongly felt that the flange technique and the use of corrugated surfaces could be merged together to obtain the advantages of both. This is the idea behind the present work. Corrugations are made on the surface of flange elements. The effect of various corrugation parameters are studied. By varying the flange parameters, a good amount of data is collected and analysed to ascertain the effects of corrugated flanges. The measurements are repeated at various frequencies, in the X— and S-bands. The following parameters of the system were studied: (a) beam shaping (b) gain (c) variation of V.S.U.R. (d) possibility of obtaining circularly polarised radiation from the flanged horn. A theoretical explanation to the effects of corrugated flanges is attempted on the basis of the line-source theory. Even though this theory utilises a simplified model for the calculation of radiation patterns, fairly good agreement between the computed pattern and experimental results are observed. |
| Description: | Department of physics, Cochin University of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3323 |
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| Dyuthi-T1293.pdf | (10.84Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1082 |
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| Zachariah E J 1982.pdf | (169.4Kb) |
| Abstract: | It is a fact that there now exists a sound framework of accounting theory to ascertain the working results and the investment status of hospitals. Yet, there is no system of accounting in practice to conduct its activities with utmost efficiency. No attempts have hitherto been made for the continuous improvement in the servics rendered by hospitals. Personal investments in hospitals have made the interaction of business to some extent.Planning, decision making and control assume increasing importance as hospitals grow in size and complexity. Moreover, wise and effective utilisation of resources should be ensured. The importance of cost cannot be overlooked in this context. Cost is the most effective factor in the determination of the prices of hospital services rendered. The important managerial functions have to rely heavily on accurate and timely cost information. More people can be provided with services if no services cost more than what is a must to provide the necessary level of care. The price paid for high cost technology for a few is no technology at all for the many. Hence no pains must be spared in ascertaining, presenting, controlling and reducing costs. An effective system of Cost Accountancy and Cost Control is imperative for the survival of hospitals in the intensely competitive conditions of today. The valuable objective of "better patient care" can be attained only if the management can make use of the various tools and techniques to ascertain, control and reduce each item of cost in hospitals. Constant efforts must be made by the management to continuously improve their services and bring down costs and prices of all hospital services. Cost Accountancy has made its impresssive impact on almost all the spheres of human activities. It is high time a comprehensive Cost Accountancy and Cost Control system be implemented in hospitals. The problem under study thus is the designing of a sound and full-fledged Cost Accountancy and Cost Control system that suits the requirements of hospitals. It is for the first time in India during the evolution of Cost Accountancy that a comprehensive cost system is tried in hospitals. |
| Description: | school of management studies, Cochin University of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3484 |
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| Dyuthi-T1476.pdf | (4.110Mb) |
| Abstract: | The creation of three-dimensionally engineered nanoporous architectures via covalently interconnected nanoscale building blocks remains one of the fundamental challenges in nanotechnology. Here we report the synthesis of ordered, stacked macroscopic three-dimensional (3D) solid scaffolds of graphene oxide (GO) fabricated via chemical cross-linking of two-dimensional GO building blocks. The resulting 3D GO network solids form highly porous interconnected structures, and the controlled reduction of these structures leads to formation of 3D conductive graphene scaffolds. These 3D architectures show promise for potential applications such as gas storage; CO2 gas adsorption measurements carried out under ambient conditions show high sorption capacity, demonstrating the possibility of creating new functional carbon solids starting with two-dimensional carbon layers |
| Description: | ACS nano,VOL 7,issue 8,pp 7034-7040 |
| URI: | http://dyuthi.cusat.ac.in/purl/4385 |
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| Covalently Inte ... Graphene Oxide Solids.pdf | (1.180Mb) |
| Abstract: | Attempts have been made to attain satisfactory network structures in each of the phases of a rubber blend by minimising the cure rate imbalance by employing methods such as grafting of accelerators to the slow curing rubber, chemically bonding the crosslinking agents to the rubber in which it has lower solubility, functionalisation of the slow curing rubber, masterbatching of the curing agents to the slow curing rubber etc. Functionalisation of the slow curing constituents of NR/IIR and NR/EIPDM blends is tried using novel reagents as the first part of this study. However, the crux of the present study is a more direct approach to attaining a covulcanized state in NR/IIR and NR/EPDM blends: Precuring the slow curing rubber (IIR or EPDM) to a low level when it can still blend with NR and then to ck) the final curing after blending with NR. TNM3 precuring is also likely to minimise the viscosity mismatch. Since a low level of resmmal crosslink density is likely to be present lJ1 reclaimed rubbers, blending heat resistant reclaimed rubber such as butyl reclaim with NR may also have the same effect of precuring IIR, and then blending with NR. Hence use of IIR reclaim for developing blends with NR is also proposed to be investigated in this study |
| Description: | Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3635 |
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| Dyuthi-T1614.pdf | (9.855Mb) |
| Abstract: | This paper presents the design and development of a compact CPW fed quad band antenna. This low profile antenna has a dimension of 32mmx31mm when printed on a substrate of dielectric constant 4.4 and height 1.6mm. The antenna covers GSM 900, DCS 1800, IEEE802.11.a, IEEE802.11.b and HiperLAN2 bands. The antenna exhibits good radiation characteristics with moderate gain |
| Description: | Applied Electromagnetics Conference (AEMC), 2009 |
| URI: | http://dyuthi.cusat.ac.in/purl/4344 |
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| CPW-Fed Quad-Ba ... t Wireless Application.pdf | (2.805Mb) |
| Abstract: | A new geometry (semiannular) for Josephson junction has been proposed and theoretical studies have shown that the new geometry is useful for electronic applications [1, 2]. In this work we study the voltage‐current response of the junction with a periodic modulation. The fluxon experiences an oscillating potential in the presence of the ac‐bias which increases the depinning current value. We show that in a system with periodic boundary conditions, average progressive motion of fluxon commences after the amplitude of the ac drive exceeds a certain threshold value. The analytic studies are justified by simulating the equation using finite‐difference method. We observe creation and annihilation of fluxons in semiannular Josephson junction with an ac‐bias in the presence of an external magnetic field. |
| URI: | http://dyuthi.cusat.ac.in/purl/2908 |
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| Dyuthi-P00407.pdf | (881.0Kb) |
| Abstract: | Hindi |
| Description: | DEPARTMENT OF HINDI Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/4897 |
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| Dyuthi-T1992.pdf | (5.717Mb) |
| Abstract: | The Union Territory of Pondicherry prior to its merger with the Indian Union was a French Colony. The erstwhile territory of Pondicherry along with its hamlets, namely, KARAIKKAL, MAHE and YANAM was administered by the French Regime. Before it was established by French in 1 6 74 A.D. it was part of Vijayanagara Empire. Prior to this, Pondicherry was a part of the Kingdom of Chola and Pallava Kings. During French Regime, the laws which were in force in France in relation to administration of civil and criminal justice were extended to the erstwhile Territory of Pondicherry. Thus while Pondicherry stood influenced by the Inquisitorial system since the beginning of the 18th century, the neighboring states forming part of the Indian Union since Independence came under the Influence of the British system, viz. accusatorial system. The territory of Pondicherry, for administrative reasons, came to be merged with the Indian Union in the early 60's. Following the merger, the Indian administration sought to extent its own laws from time to time replacing erstwhile French Laws, however, subject to certain savings. Thus the transitional period witnessed consequential changes in the administration of the territory, including the sphere of judicial system. Since I 963, the Union Territory of Pondicherry was brought under the spell of the Indian Legal System The people in Pondicherry ' thus have had the benefit of experiencing both the svstems. Their experiences will be of much help to those who undertake comparative studies in law. The plus and minus points of the respective systems help one to develop a detachment that helps independent evaluation of the svstents. The result of these studies could be relevant in revitalising our criminal systems.The present system is evaluated in the light of the past system. New dimensions are added by way' of an empirical study also. |
| Description: | School of Legal Studies, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3276 |
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| Dyuthi-T1250.pdf | (31.96Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1340 |
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| Paulson Chunkapura 1988.PDF | (907.7Kb) |
| Abstract: | Chapter 1 presents a brief note on the state at which the construction industry stands at present, bringing into focus the significance of the critical study. Relevance of the study, area of investigation and objectives of the study are outlined in this chapter. The 2nd chapter presents a review of the literature on the relevant areas. In the third chapter an analysis on time and cost overrun in construction highlighting the major factors responsible for it has been done. A couple of case studies to estimate loss to the nation on account of delay in construction have been presented in the chapter. The need for an appropriate estimate and a competent contractor has been emphasised for improving effectiveness in the project implementation. Certain useful equations and thoughts have been formulated on this area in this chapter that can be followed in State PWD and other Govt. organisations. Case studies on project implementation of major projects undertaken by Government sponsored/supported organizations in Kerala have been dealt with in Chapter 4. A detailed description of the project of Kerala Legislature Complex with a critical analysis has been given in this chapter. A detailed account of the investigations carried out on the construction of International Stadium, a sports project of Greater Cochin Development Authority is included here. The project details of Cochin International Airport at Nedumbassery, its promoters and contractors are also discussed in Chapter 4. Various aspects of implementation which led the above projects successful have been discussed in chapter 5. The data collected were analysed through discussion and perceptions to arrive at certain conclusions. The emergence of front-loaded contract and its impact on economics of the project execution are dealt with in this chapter. Analysis of delays in respect of the various project narrated in chapter 3 has been done here. The root causes of the project time and overrun and its remedial measures are also enlisted in this chapter. Study of cost and time overrun of any construction project IS a part of construction management. Under the present environment of heavy investment on construction activities in India, the consequences of mismanagement many a time lead to excessive expenditure which are not be avoidable. Cost consciousness, therefore has to be keener than ever before. Optimization in investment can be achieved by improved dynamism in construction management. The successful completion of coristruction projects within the specified programme, optimizing three major attributes of the process - quality, schedule and costs - has become the most valuable and challenging task for the engineer - managers to perform. So, the various aspects of construction management such as cost control, schedule control, quality assurance, management techniques etc. have also been discussed in this fifth chapter. Chapter 6 summarises the conclusions drawn from the above criticalr1 of rhajor construction projects in Kerala. |
| Description: | School of Engineering,Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3255 |
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| Dyuthi-T1229.pdf | (9.291Mb) |
| Abstract: | Hindi |
| Description: | Department of hindi,CUSAT |
| URI: | http://dyuthi.cusat.ac.in/purl/4776 |
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| Dyuthi-T1873.pdf | (25.50Mb) |
| Abstract: | HINDI |
| Description: | Department of Hindi, Cochin University of science & Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/4809 |
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| Dyuthi-T1906.pdf | (11.65Mb) |
| Abstract: | Cryptosystem using linear codes was developed in 1978 by Mc-Eliece. Later in 1985 Niederreiter and others developed a modified version of cryptosystem using concepts of linear codes. But these systems were not used frequently because of its larger key size. In this study we were designing a cryptosystem using the concepts of algebraic geometric codes with smaller key size. Error detection and correction can be done efficiently by simple decoding methods using the cryptosystem developed. Approach: Algebraic geometric codes are codes, generated using curves. The cryptosystem use basic concepts of elliptic curves cryptography and generator matrix. Decrypted information takes the form of a repetition code. Due to this complexity of decoding procedure is reduced. Error detection and correction can be carried out efficiently by solving a simple system of linear equations, there by imposing the concepts of security along with error detection and correction. Results: Implementation of the algorithm is done on MATLAB and comparative analysis is also done on various parameters of the system. Attacks are common to all cryptosystems. But by securely choosing curve, field and representation of elements in field, we can overcome the attacks and a stable system can be generated. Conclusion: The algorithm defined here protects the information from an intruder and also from the error in communication channel by efficient error correction methods. |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/2007 |
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| A Cryptosystem using....pdf | (93.25Kb) |
| Abstract: | The current scenario of coordination chemistry is witnessing the exploitation of coordination bonds and noncovalent interactions to generate self-assemblies of various dimensions having not only aesthetic values but also countless applications and that paved way for supramolecular chemistry/crystal engineering. Most of such fascinating work employs Schiff bases obtained by the condenzation of an amine and a carbonyl compound. The use of diamines in the synthesis of highnuclearity complexes utilizes the bridging capacity of phenoxo atoms. Whereas in the case of N2O donor tridentate Schiff bases (N-substituted diamines with salicylaldehyde or its derivatives), coligands are employed to generate structures of variable composition apart from satisfying the coordination number. Among the various coligands known, pseudohalides (azido, cyanato, thiocyanato, dicyanamido) deserve special attention on account of its versatile modes of binding. In addition to the structural variety, such Schiff base complexes have its signature in the field of catalysis, luminescence, gas adsorption and magnetic materials which make the arena conspicuous. The recognition of plasticity of copper(II) metal with respect to its coordination number and its ubiquitous nature as active sites in many metalloenzymes fuelled us to work with this metal. The results of our efforts to explore the role of various interaction forces constitute the subject matter of the thesis entitled “Crystalline architectures of copper(II) complexes derived from halogen substituted carbonyl compounds: Interplay of covalent and non-covalent forces”. The work embodied in this thesis was carried out by the author in the Department of Applied Chemistry, CUSAT, Kochi, during the period 2011-2016 and is divided into eight chapters. |
| URI: | http://dyuthi.cusat.ac.in/purl/5137 |
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| Dyuthi-T2171.pdf | (24.08Mb) |
| Abstract: | Thiosemicarbazones have emerged as an important class of ligands over a period of time, for a variety of reasons, such as variable donor properties, structural diversity and biological applications. Interesting as the coordination chemistry may be, the driving force for the study of these ligands has undoubtedly been their biological properties and the majority of the 3000 or so publications on thiosemicarbazones since 2000 have alluded to this feature. Thiosemicarbazones with potential donor atoms in their structural skeleton fascinate coordination chemists with their versatile chelating behavior. The thiosemicarbazones of aromatic aldehydes and ketones form stable chelates with transition metal cations by utilizing both their sulfur and azomethine nitrogen as donor atoms. They have been shown to possess a diverse range of biological activities including anticancer, antitumor, antibacterial, antiviral, antimalarial and antifungal properties owing to their ability to diffuse through the semipermeable membrane of the cell lines. The enhanced effect may be attributed to the increased lipophilicity of the metal complexes compared to the ligand alone. |
| Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3747 |
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| Dyuthi-T1709.pdf | (5.286Mb) |
| Abstract: | Supra molecular architectures of coordination complexes of liydrazones through non covalent interactions have been explored. Molecular self—assernbly driven by weak interactions such as hydrogen— bonding, K '”T[, C-1-I‘ "TE, van der Waals interactions, and so forth are currently of tremendous research interest in the fields of molecule based materials. The directional properties of the hydrogembonding interaction associate discrete molecules into aggregate structures that are sufficiently stable to be considered as independent chemical species. Chemistry can borrow nature’s strategy to utilize hydrogen-bonding as Well as other noncovalent interactions as found in secondary and tertiary structures of proteins such as the double helix folding of DNA, hydrophobic selflorganization of phospholipids in cell membrane etc. In supramolecular chemistry hydrogen bonding plays an important role in forming a variety of architectures. Thus, the wise modulation and tuning of the complementary sites responsible for hydrogen—bond formation have led to its application in supramolecular electronics, host-guest chemistry, self-assembly of molecular capsules, nanotubes etc. The work presented in this thesis describes the synthesis and characterization of metal complexes derived from some substituted aroylhydrazones. The thesis is divided into seven chapters. |
| Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3491 |
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| Dyuthi-T1430.pdf | (3.011Mb) |
| Abstract: | A new electronically reconfigurable dual frequency microstrip patch antenna with highly simplified varactor tuning circuitry is presented. The proposed design allows relatively independent selection of the two operating frequencies. Tuning ranges of 7.1 and 4.1% are realised for the two resonant frequencies without the use of any matching circuits. |
| URI: | http://dyuthi.cusat.ac.in/purl/2758 |
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| Dyuthi-P00377.pdf | (94.62Kb) |
| Abstract: | Thin film solar cells having structure CuInS2/In2S3 were fabricated using chemical spray pyrolysis (CSP) technique over ITO coated glass. Top electrode was silver film (area 0.05 cm2). Cu/In ratio and S/Cu in the precursor solution for CuInS2 were fixed as 1.2 and 5 respectively. In/S ratio in the precursor solution for In2S3 was fixed as 1.2/8. An efficiency of 0.6% (fill factor -37.6%) was obtained. Cu diffusion to the In2S3 layer, which deteriorates junction properties, is inevitable in CuInS2/In2S3 cell. So to decrease this effect and to ensure a Cu-free In2S3 layer at the top of the cell, Cu/In ratio was reduced to 1. Then a remarkable increase in short circuit current density was occurred from 3 mA/cm2 to 14.8 mA/cm2 and an efficiency of 2.13% was achieved. Also when In/S ratio was altered to 1.2/12, the short circuit current density increased to 17.8 mA/cm2 with an improved fill factor of 32% and efficiency remaining as 2%. Thus Cu/In and In/S ratios in the precursor solutions play a crucial role in determining the cell parameters |
| Description: | Energy Procedia 15 ( 2012 ) 283 – 290 |
| URI: | http://dyuthi.cusat.ac.in/purl/4722 |
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| CuInS2In2S3 Cel ... ios on Cell Parameters.pdf | (1.060Mb) |
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