964 resultados para Photographic reproduction of plans, drawings, etc.


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The thesis mainly focuses on material characterization in different environments: freely available samples taken in planar fonn, biological samples available in small quantities and buried objects.Free space method, finds many applications in the fields of industry, medicine and communication. As it is a non-contact method, it can be employed for monitoring the electrical properties of materials moving through a conveyor belt in real time. Also, measurement on such systems at high temperature is possible. NID theory can be applied to the characterization of thin films. Dielectric properties of thin films deposited on any dielectric substrate can be determined. ln chemical industry, the stages of a chemical reaction can be monitored online. Online monitoring will be more efficient as it saves time and avoids risk of sample collection.Dielectric contrast is one of the main factors, which decides the detectability of a system. lt could be noted that the two dielectric objects of same dielectric constant 3.2 (s, of plastic mine) placed in a medium of dielectric constant 2.56 (er of sand) could even be detected employing the time domain analysis of the reflected signal. This type of detection finds strategic importance as it provides solution to the problem of clearance of non-metallic mines. The demining of these mines using the conventional techniques had been proved futile. The studies on the detection of voids and leakage in pipes find many applications.The determined electrical properties of tissues can be used for numerical modeling of cells, microwave imaging, SAR test etc. All these techniques need the accurate determination of dielectric constant. ln the modem world, the use of cellular and other wireless communication systems is booming up. At the same time people are concemed about the hazardous effects of microwaves on living cells. The effect is usually studied on human phantom models. The construction of the models requires the knowledge of the dielectric parameters of the various body tissues. lt is in this context that the present study gains significance. The case study on biological samples shows that the properties of normal and infected body tissues are different. Even though the change in the dielectric properties of infected samples from that of normal one may not be a clear evidence of an ailment, it is an indication of some disorder.ln medical field, the free space method may be adapted for imaging the biological samples. This method can also be used in wireless technology. Evaluation of electrical properties and attenuation of obstacles in the path of RF waves can be done using free waves. An intelligent system for controlling the power output or frequency depending on the feed back values of the attenuation may be developed.The simulation employed in GPR can be extended for the exploration of the effects due to the factors such as the different proportion of water content in the soil, the level and roughness of the soil etc on the reflected signal. This may find applications in geological explorations. ln the detection of mines, a state-of-the art technique for scanning and imaging an active mine field can be developed using GPR. The probing antenna can be attached to a robotic arm capable of three degrees of rotation and the whole detecting system can be housed in a military vehicle. In industry, a system based on the GPR principle can be developed for monitoring liquid or gas through a pipe, as pipe with and without the sample gives different reflection responses. lt may also be implemented for the online monitoring of different stages of extraction and purification of crude petroleum in a plant.Since biological samples show fluctuation in the dielectric nature with time and other physiological conditions, more investigation in this direction should be done. The infected cells at various stages of advancement and the normal cells should be analysed. The results from these comparative studies can be utilized for the detection of the onset of such diseases. Studying the properties of infected tissues at different stages, the threshold of detectability of infected cells can be determined.

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The Indian edible oyster Crassostrea madrasensis (Preston) is known to be a highly suitable candidate species for culture. Though Q, madrasensis has been subjected to intensive research, there has been no significant attempt to culture this oyster commercially. One major reason for the lack of interest in oyster culture could be the disparity in growth, survival and production reported by earlier workersf from different regions along the Indian coast. Greater predictability of production can create confidence and encourage entrepreneurs interested in oyster culture. The present study, which is a detailed investigation on the influence of various environmental variables on growth and reproduction of Q, madrasensis, is not confined to the impact of only hydrological parameters but is also extended to study the effect of different degrees of aerial exposure on growth and survival. The main objective of the study is to develop a background for subsequent development of a site suitability index for culture of Q, madrasensis along the Indian coast. Two sets of experiments were conducted during the present study. Details of the experiments are presented in the thesis under two major chapters comprising four sections each. Each chapter has a separate introduction, materials and methods, results and discussion. .

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Though of recent origin, commercial poultry farming has achieved momentum in Kerala because of its wide and varied potentials capability of employment creation, low investment, quick returns, lesser combination of various factors of production, enhanced productivity per unit of agricultural land, maintenance of soil fertility etc. Despite all the ancillary attributes characteristic of a thriving venture, the performance of poultry farming in Kerala was not comforting, especially in the case of small and medium size farms. This study has aimed at detailing the various components of cost and revenue in the business of poultry farming, and the adducing of empirical evidences on the nature of relationship of different variables as the gross income, current rate of productivity, extent of capacity utilisation and size of farms in terms of number of birds reared and the farms’ overall financial performance. Alongwith this a descriptive approach was made to highlight the challenges and opportunity poultry farming in Kerala, with special emphasis on its economic and financial aspects.

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The main challenges in the deposition of cathode materials in thin film form are the reproduction of stoichiometry close to the bulk material and attaining higher rates of deposition and excellent crystallinity at comparatively lower annealing temperatures. There are several methods available to develop stoichiometric thin film cathode materials including pulsed laser deposition; plasma enhanced chemical vapor deposition, electron beam evaporation, electrostatic spray deposition and RF magnetron sputtering. Among them the most versatile method is the sputtering technique, owing to its suitability for micro-fabricating the thin film batteries directly on chips in any shape or size, and on flexible substrates, with good capacity and cycle life. The main drawback of the conventional sputtering technique using RF frequency of 13.56MHz is its lower rate of deposition, compared to other deposition techniques A typical cathode layer for a thin film battery requires a thickness around one micron. To deposit such thick layers using convention RF sputtering, longer time of deposition is required, since the deposition rate is very low, which is typically 10-20 Å/min. This makes the conventional RF sputtering technique a less viable option for mass production in an economical way. There exists a host of theoretical and experimental evidences and results that higher excitation frequency can be efficiently used to deposit good quality films at higher deposition rates with glow discharge plasma. The effect of frequencies higher than the conventional one (13.56MHz) on the RF magnetron sputtering process has not been subjected to detailed investigations. Attempts have been made in the present work, to sputter deposit spinel oxide cathode films, using high frequency RF excitation source. Most importantly, the major challenge faced by the thin film battery based on the LiMn2O4 cathode material is the poor capacity retention during charge discharge cycling. The major causes for the capacity fading reported in LiMn2O4cathode materials are due to, Jahn-Teller distortion, Mn2+ dissolution into the electrolyte and oxygen loss in cathode material during cycling. The work discussed in this thesis is an attempt on overcoming the above said challenges and developing a high capacity thin film cathode material.

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Frozen storage characteristics and shelflife vary considerably among species as well as within the species (Powrie, 1973; Fennema. 1973). This can be attributed to the variation in the composition of fish among various species. In certain species like sardines and mackerel. wide seasonal variation in chemical composition occur within the species. These variations affect the quality and shelflife. The nutritional level of water. spawning, method of catching, struggling etc. are found to have profound influence on the condition of the fresh fish. Soon after death the deteriorative changes in fish start due to autolysis and bacterial growth. The rate of these changes depends mainly on temperature. The handling methods have great influence on bacterial contamination. Thus the type oi'handling. temperature control. period of chill storage. processing methods. type of freezing, condition of frozen storage and period of storage affect the quality and shelflife Of the fisho In the present study extensive investigations were carried out on various factors affecting the quality of fish as well as their effect on the physical. chemical and sensory qualities of fish during frozen storage and the shelflife

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The study is intended to estimate the existing rate of participation of women beneficiaries in the development programmes of different organisations in Kerala. It would enable one to understand whether participation is at the satisfactory level or not. Given the rate of participation, the major thrust of the analysis is on the impact of governmental and non-governmental organisations on the rate of participation. This is undertaken under the assumption that NGOs, due to their proximity to people and their needs, ensure better participation rates. Besides the organisational differences, the other major determinants of women participation such as their socio-economic characteristics, psychological make up, the nature of the programme etc. are also highlighted. 0 Since the ascribed status of women in society is inferior, the role of organisers, development personnel and local leaders is also pointed out. Thus the basic objective of the study is women participation and its determinants in the development programmes

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A theoretical study of the physicochemical properties of elements 104, 105, and 106 and their compounds in the gas phase and aqueous solutions has been undertaken using relativistic atomic and molecular codes. Trends in properties such as bonding, ionization potentials, electron affinities, energies of electronic transitions, stabilities of oxidation states etc. have been defined within the corresponding chemical groups and within the transactinides. These trends are shown to be determined by increasing relativistic effects within the groups. The behaviour of some gas phase compounds and complexes in solutions is predicted for the gas chromatography and solvent extraction experiments. Redox potentials in aqueous solutions of these elements are estimated.

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The theoretical model and underlying physics described in this thesis are about the interaction of femtosecond-laser and XUV pulses with solids. The key to understand the basics of such interaction is to study the structural response of the materials after laser interaction. Depending on the laser characteristics, laser-solid interaction can result in a wide range of structural responses such as solid-solid phase transitions, vacuum phonon squeezing, ultrafast melting, generation of coherent phonons, etc. During my research work, I have modeled the systems irradiated by low-, medium- and high-laser intensities, and studied different types of structural dynamics of solids at various laser fluences.

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Computational theories of action have generally understood the organized nature of human activity through the construction and execution of plans. By consigning the phenomena of contingency and improvisation to peripheral roles, this view has led to impractical technical proposals. As an alternative, I suggest that contingency is a central feature of everyday activity and that improvisation is the central kind of human activity. I also offer a computational model of certain aspects of everyday routine activity based on an account of improvised activity called running arguments and an account of representation for situated agents called deictic representation .

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In this paper we search the concept of nonviolent resistance inquiring a rural experience from Rio Negro´s steppe. The initiative highlights the need to recognize  the context of the resistance exercise and the consideration of three aspects: the evaluation and interpretation of space, the dispute to public policy and the  restructuring of the family order. These three elements, which overlap material  and symbolic aspects, are discussed from an organization of trade domestic craft production. The notion of “development” is discovered on the basis of the  frameworks of values from which the reproduction of subordination is associated  with this idea, and even the challenge of change is the basis of the proposal which reviews that development idea, and illuminates from this complexity the notion  of “nonviolent resistance”.

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Este artículo es una versión reducida del original publicado en la Revista Current History, Vol. 105, No. 688, febrero, 2006, pp. 79-86. La revista Desafíos ha decidido publicar apartes por considerarlo de interés para la discusión sobre los efectos y resultados de la política de erradicación de cultivos ilícitos en Colombia. – This article is an abbreviated reproduction of the article published in the Current History Journal, Vol. 105, Nr. 688, Februrary, 2006, pp. 79-86. Desafíos Journal decided to publish parts of it due to the consideration of its interest for the discussion on consequences and results of the eradication policy of ilegal crops in Colombia.An anti-narcotics policy that ignores the social consequences of drug crops eradication only manages to further radicalize and isolate the population in areas in which lawlessness and potential terrorist activity thrive. It also strengthens the bond between disaffected social groups and guerrilla organizations in these areas. Washington cannot continue to be blind to the fact that the three current US policies on counterterrorism, anti-narcotics, and democratization in Peru and elsewhere in Latin America, are not working in harmony. Paradoxically, the eradication of drug crops —the core of Peru’s US-sponsored anti-narcotics policy— enlarges pockets of poverty and fuels anger against the government. It also perpetuates the proverbial quagmire of alienation in which terrorism breeds. Instead of strengthening the State, drug eradication, particularly in the way it is currently carried out in the Andean countries, increases the risk of State failure.-----El efecto de una política antinarcóticos que ignora las consecuencias de la erradicación de cultivos de coca es radicalizar y aislar aún más la población en aquellas zonas donde prosperan la anarquía y el terrorismo. Además, fortalece los lazos entre los descontentos sociales y los grupos guerrilleros en esas mismas áreas. Washington no puede seguir ciega al hecho de que las tres políticas actuales de Estados Unidos —antiterrorismo, antinarcóticos y democratización en el Perú y otras regiones en América Latina— no están funcionando armónicamente. Resulta paradójico que la erradicación de cultivos de coca -eje de la política antinarcóticos peruana respaldada por Estados Unidos- ensanche las bolsas de miseria y aliente la ira contra el gobierno, además de perpetuar los proverbiales miasmas de marginación en las que se engendra el terrorismo. En vez de fortalecer al Estado, la erradicación de cultivos de coca, tal y como se está llevando a cabo en los países andinos, incrementa las posibilidades de su fracaso.

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Este proyecto fue galardonado con el 1er Premio de Innovación Educativa 2009.

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The work developed in LUDA’s project has clearly showed that, in a European economic and cultural diversified frame, crossed by recent and not so recent historical challenging processes, the issues of the urban affairs certainly have different layouts, but, as a matter of fact, we can assume that in their essence they are common to all regions. Identifying a set of common problems is not difficult: the Luda’s; the disadjustment between people and goods mobility, the difficult articulation between space and development sustainability the fragile features of the urban space in its complexity, the responsible social management of current migrations etc.

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The point of departure for these reflections is life, since its protection is the central purpose encouraging the defense of human rights and of public health. Life in the Andes has an exceptional diversity. Particularly in Ecuador, my country, this diversity constitutes a characteristic sign that is expressed in two main forms: natural megadiversity and multiculturalism. Indeed, Ecuador’s small territory synthesizes practically all types of lifezones that exist on Earth, having received the gift of high average rates of solar energy and abundant nutritional sources, which have facilitated the natural reproduction of countless species that show their beautiful vitality in the variety of ecosystems that compose the Andean mountain range, the tropical plains, the Amazon humid forests, and the Galapagos Islands. But besides being a highly biodiverse country, it is also a plurinational and multi-cultural society, in which the activity of human beings, organized into social conglomerates of different historical and cultural backgrounds, have formed more than a dozen nations and peoples. Regrettably this natural and human wealth has not been able to bear its best fruits due to the violent operation of a deep social inequity – unfortunately also one of the highest in the Americas—which conspires against life and is reproduced in national and international inequitable relations. This structural inequity has changed its form throughout the centuries and currently has reached its highest and most perverse level of development.

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Ecological risk assessments must increasingly consider the effects of chemical mixtures on the environment as anthropogenic pollution continues to grow in complexity. Yet testing every possible mixture combination is impractical and unfeasible; thus, there is an urgent need for models that can accurately predict mixture toxicity from single-compound data. Currently, two models are frequently used to predict mixture toxicity from single-compound data: Concentration addition and independent action (IA). The accuracy of the predictions generated by these models is currently debated and needs to be resolved before their use in risk assessments can be fully justified. The present study addresses this issue by determining whether the IA model adequately described the toxicity of binary mixtures of five pesticides and other environmental contaminants (cadmium, chlorpyrifos, diuron, nickel, and prochloraz) each with dissimilar modes of action on the reproduction of the nematode Caenorhabditis elegans. In three out of 10 cases, the IA model failed to describe mixture toxicity adequately with significant or antagonism being observed. In a further three cases, there was an indication of synergy, antagonism, and effect-level-dependent deviations, respectively, but these were not statistically significant. The extent of the significant deviations that were found varied, but all were such that the predicted percentage effect seen on reproductive output would have been wrong by 18 to 35% (i.e., the effect concentration expected to cause a 50% effect led to an 85% effect). The presence of such a high number and variety of deviations has important implications for the use of existing mixture toxicity models for risk assessments, especially where all or part of the deviation is synergistic.