874 resultados para image and information
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Transmission electron microscopy is a proven technique in the field of cell biology and a very useful tool in biomedical research. Innovation and improvements in equipment together with the introduction of new technology have allowed us to improve our knowledge of biological tissues, to visualizestructures better and both to identify and to locate molecules. Of all the types ofmicroscopy exploited to date, electron microscopy is the one with the mostadvantageous resolution limit and therefore it is a very efficient technique fordeciphering the cell architecture and relating it to function. This chapter aims toprovide an overview of the most important techniques that we can apply to abiological sample, tissue or cells, to observe it with an electron microscope, fromthe most conventional to the latest generation. Processes and concepts aredefined, and the advantages and disadvantages of each technique are assessedalong with the image and information that we can obtain by using each one ofthem.
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Large area hydrogenated amorphous silicon single and stacked p-i-n structures with low conductivity doped layers are proposed as monochrome and color image sensors. The layers of the structures are based on amorphous silicon alloys (a-Si(x)C(1-x):H). The current-voltage characteristics and the spectral sensitivity under different bias conditions are analyzed. The output characteristics are evaluated under different read-out voltages and scanner wavelengths. To extract information on image shape, intensity and color, a modulated light beam scans the sensor active area at three appropriate bias voltages and the photoresponse in each scanning position ("sub-pixel") is recorded. The investigation of the sensor output under different scanner wavelengths and varying electrical bias reveals that the response can be tuned, thus enabling color separation. The operation of the sensor is exemplified and supported by a numerical simulation.
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Classical treatments of problems of sequential mate choice assume that the distribution of the quality of potential mates is known a priori. This assumption, made for analytical purposes, may seem unrealistic, opposing empirical data as well as evolutionary arguments. Using stochastic dynamic programming, we develop a model that includes the possibility for searching individuals to learn about the distribution and in particular to update mean and variance during the search. In a constant environment, a priori knowledge of the parameter values brings strong benefits in both time needed to make a decision and average value of mate obtained. Knowing the variance yields more benefits than knowing the mean, and benefits increase with variance. However, the costs of learning become progressively lower as more time is available for choice. When parameter values differ between demes and/or searching periods, a strategy relying on fixed a priori information might lead to erroneous decisions, which confers advantages on the learning strategy. However, time for choice plays an important role as well: if a decision must be made rapidly, a fixed strategy may do better even when the fixed image does not coincide with the local parameter values. These results help in delineating the ecological-behavior context in which learning strategies may spread.
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Naive scale invariance is not a true property of natural images. Natural monochrome images possess a much richer geometrical structure, which is particularly well described in terms of multiscaling relations. This means that the pixels of a given image can be decomposed into sets, the fractal components of the image, with well-defined scaling exponents [Turiel and Parga, Neural Comput. 12, 763 (2000)]. Here it is shown that hyperspectral representations of natural scenes also exhibit multiscaling properties, observing the same kind of behavior. A precise measure of the informational relevance of the fractal components is also given, and it is shown that there are important differences between the intrinsically redundant red-green-blue system and the decorrelated one defined in Ruderman, Cronin, and Chiao [J. Opt. Soc. Am. A 15, 2036 (1998)].
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TUTKIMUKSEN TAVOITTEET Tutkielman tavoitteena oli luoda ensin yleiskäsitys tuotemerkkimarkkinoinnin roolista teollisilla markkinoilla, sekä suhdemarkkinoinnin merkityksestä teollisessa merkkituotemarkkinoinnissa. Toisena oleellisena tavoitteena oli kuvata teoreettisesti merkkituoteidentiteetin rakenne teollisessa yrityksessä ja sen vaikutukset myyntihenkilöstöön, ja lisäksi haluttiin tutkia tuotemerkkien lisäarvoa sekä asiakkaalle että myyjälle. Identiteetti ja sen vaikutukset, erityisesti imago haluttiin tutkia myös empiirisesti. LÄHDEAINEISTO JA TUTKIMUSMENETELMÄT Tämän tutkielman teoreettinen osuus perustuu kirjallisuuteen, akateemisiin julkaisuihin ja aikaisempiin tutkimuksiin; keskittyen merkkituotteiden markkinointiin, identiteettiin ja imagoon, sekä suhdemarkkinointiin osana merkkituotemarkkinointia. Tutkimuksen lähestymistapa on kuvaileva eli deskriptiivinen ja sekä kvalitatiivinen että kvantitatiivinen. Tutkimus on tapaustutkimus, jossa caseyritykseksi valittiin kansainvälinen pakkauskartonki-teollisuuden yritys. Empiirisen osuuden toteuttamiseen käytettiin www-pohjaista surveytä, jonka avulla tietoja kerättiin myyntihenkilöstöltä case-yrityksessä. Lisäksi empiiristä osuutta laajennettiin tutkimalla sekundäärilähteitä kuten yrityksen sisäisiä kirjallisia dokumentteja ja tutkimuksia. TULOKSET. Teoreettisen ja empiirisen tutkimuksen tuloksena luotiin malli jota voidaan hyödyntää merkkituotemarkkinoinnin päätöksenteon tukena pakkauskartonki-teollisuudessa. Teollisen brandinhallinnan tulee keskittyä erityisesti asiakas-suhteiden brandaukseen – tätä voisi kutsua teolliseksi suhdebrandaukseksi. Tuote-elementit ja –arvot, differointi ja positiointi, sisäinen yrityskuva ja viestintä ovat teollisen brandi-identiteetin peruskiviä, jotka luovat brandi-imagon. Case-yrityksen myyntihenkilöstön tuote- ja yritysmielikuvat osoittautuivat kokonaisuudessaan hyviksi. Paras imago on CKB tuotteilla, kun taas heikoin on WLC tuotteilla. Teolliset brandit voivat luoda monenlaisia lisäarvoja sekä asiakas- että myyjäyritykselle.
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The main objective of this Master’s Thesis was to examine the perceived city brand image of tourists and residents. It was aimed to accomplish by examining first the contribution of city attributes and marketing communications on forming brand attitudes, and then discover how the brand attitudes influence on city brand image. The impact of brand attitudes and city brand image on behavioral intention was also reviewed. The empirical part of the thesis was conducted with a quantitative method through online-based survey. The sample (n = 492) consisted of tourists and residents of the case city. The data was analyzed with statistical analyses by SPSS program. Brand attitudes, based on the main attributes, were calculated through multi-attribute attitude model. The results confirmed exposure to marketing communications has direct and positive influence on brand attitudes, especially the offline marketing communications. The findings revealed brand attitudes impact directly on city brand image perception. Brand attitudes and brand image dimensions had direct impact on tourists and residents’ behavioral intention. The findings provide important information for the city marketers. They increase marketers understanding on how target population perceives the city brand image and how it impacts on their future behavior. This thesis reveals the perception of current city brand image and gives guidance on what to emphasize in city branding to increase city’s attractiveness in conjunction with its economic development. Furthermore, the created framework can be utilized also in the future researches.
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A new proposal to have secure communications in a system is reported. The basis is the use of a synchronized digital chaotic systems, sending the information signal added to an initial chaos. The received signal is analyzed by another chaos generator located at the receiver and, by a logic boolean function of the chaotic and the received signals, the original information is recovered. One of the most important facts of this system is that the bandwidth needed by the system remain the same with and without chaos.
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Background: Minimally invasive surgery creates two technological opportunities: (1) the development of better training and objective evaluation environments, and (2) the creation of image guided surgical systems.
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Concern has been expressed in the professional literature - borne out by professional experience and observation - that the supply and demand relationship existing between the 13 English and Welsh Library and Information Studies (LIS) Schools (as providers of `First Professional' staff) and the Higher Education Library and Information Services (HE LIS) sector of England and Wales (as one group of employers of such staff) is unsatisfactory and needs attention. An appropriate methodology to investigate this problem was devised. A basic content analysis of Schools' curricular and recruitment material intended for public consumption was undertaken to establish an overview of the LIS initial professional education system in England and Wales, and to identify and analyse any covert messages imparted to readers. This was followed by a mix of Main Questionnaires and Semi-Structured Interviews with appropriate populations. The investigation revealed some serious areas of dissatisfaction by the HE LIS Chiefs with the role and function of the Schools. Considerable divergence of views emerged on the state of the working relationships between the two sectors and on the Schools' successes in meeting the needs of the HE LIS sector and on CPD provision. There were, however, areas of substantial and consistent agreement between the two sectors. The main implications of the findings were that those areas encompassing divergence of views were worrying and needed addressing by both sides. Possible ways forward included recommendations on improving the image of the profession purveyed by the Schools; the forming of closer and more effective inter-sectoral relationships; recognising fully the importance of `practicum' and increasing and sustaining the network of `practicum' providers.
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A circumpolar representative and consistent wetland map is required for a range of applications ranging from upscaling of carbon fluxes and pools to climate modelling and wildlife habitat assessment. Currently available data sets lack sufficient accuracy and/or thematic detail in many regions of the Arctic. Synthetic aperture radar (SAR) data from satellites have already been shown to be suitable for wetland mapping. Envisat Advanced SAR (ASAR) provides global medium-resolution data which are examined with particular focus on spatial wetness patterns in this study. It was found that winter minimum backscatter values as well as their differences to summer minimum values reflect vegetation physiognomy units of certain wetness regimes. Low winter backscatter values are mostly found in areas vegetated by plant communities typically for wet regions in the tundra biome, due to low roughness and low volume scattering caused by the predominant vegetation. Summer to winter difference backscatter values, which in contrast to the winter values depend almost solely on soil moisture content, show expected higher values for wet regions. While the approach using difference values would seem more reasonable in order to delineate wetness patterns considering its direct link to soil moisture, it was found that a classification of winter minimum backscatter values is more applicable in tundra regions due to its better separability into wetness classes. Previous approaches for wetland detection have investigated the impact of liquid water in the soil on backscatter conditions. In this study the absence of liquid water is utilized. Owing to a lack of comparable regional to circumpolar data with respect to thematic detail, a potential wetland map cannot directly be validated; however, one might claim the validity of such a product by comparison with vegetation maps, which hold some information on the wetness status of certain classes. It was shown that the Envisat ASAR-derived classes are related to wetland classes of conventional vegetation maps, indicating its applicability; 30% of the land area north of the treeline was identified as wetland while conventional maps recorded 1-7%.
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Inverse problems are at the core of many challenging applications. Variational and learning models provide estimated solutions of inverse problems as the outcome of specific reconstruction maps. In the variational approach, the result of the reconstruction map is the solution of a regularized minimization problem encoding information on the acquisition process and prior knowledge on the solution. In the learning approach, the reconstruction map is a parametric function whose parameters are identified by solving a minimization problem depending on a large set of data. In this thesis, we go beyond this apparent dichotomy between variational and learning models and we show they can be harmoniously merged in unified hybrid frameworks preserving their main advantages. We develop several highly efficient methods based on both these model-driven and data-driven strategies, for which we provide a detailed convergence analysis. The arising algorithms are applied to solve inverse problems involving images and time series. For each task, we show the proposed schemes improve the performances of many other existing methods in terms of both computational burden and quality of the solution. In the first part, we focus on gradient-based regularized variational models which are shown to be effective for segmentation purposes and thermal and medical image enhancement. We consider gradient sparsity-promoting regularized models for which we develop different strategies to estimate the regularization strength. Furthermore, we introduce a novel gradient-based Plug-and-Play convergent scheme considering a deep learning based denoiser trained on the gradient domain. In the second part, we address the tasks of natural image deblurring, image and video super resolution microscopy and positioning time series prediction, through deep learning based methods. We boost the performances of supervised, such as trained convolutional and recurrent networks, and unsupervised deep learning strategies, such as Deep Image Prior, by penalizing the losses with handcrafted regularization terms.
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The parallel mutation-selection evolutionary dynamics, in which mutation and replication are independent events, is solved exactly in the case that the Malthusian fitnesses associated to the genomes are described by the random energy model (REM) and by a ferromagnetic version of the REM. The solution method uses the mapping of the evolutionary dynamics into a quantum Ising chain in a transverse field and the Suzuki-Trotter formalism to calculate the transition probabilities between configurations at different times. We find that in the case of the REM landscape the dynamics can exhibit three distinct regimes: pure diffusion or stasis for short times, depending on the fitness of the initial configuration, and a spin-glass regime for large times. The dynamic transition between these dynamical regimes is marked by discontinuities in the mean-fitness as well as in the overlap with the initial reference sequence. The relaxation to equilibrium is described by an inverse time decay. In the ferromagnetic REM, we find in addition to these three regimes, a ferromagnetic regime where the overlap and the mean-fitness are frozen. In this case, the system relaxes to equilibrium in a finite time. The relevance of our results to information processing aspects of evolution is discussed.
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This text aims to approach museums` role in the production of knowledge and how objects are transformed into documents when museums incorporate them. On accepting the effects of such transformation, museums start working not only with material goods, but also symbolic goods. The collection manager or exhibition curator communicate through documents rather than bringing into light its intrinsic content. In this sense, every process involving museum documents, from the selection of collections to exhibitions, has a rhetoric and ideological nature which is given. Museums must search for meanings through correlations established in the process of producing information. Exhibitions should present objects in multiple contexts, giving visitors the opportunity to participate and attribute their own meanings to them.
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A great deal of attention in the supply chain management literature is devoted to study material and demand information flows and their coordination. But in many situations, supply chains may convey information from different nature, they may be an important channel companies have to deliver knowledge, or specifically, technical information to the market. This paper studies the technical flow and highlights its particular requirements. Drawing upon a qualitative field research, it studies pharmaceutical companies, since those companies face a very specific challenge: consumers do not have discretion over their choices, ethical drugs must be prescribed by physicians to be bought and used by final consumers. Technical information flow is rich, and must be redundant and early delivered at multiple points. Thus, apart from the regular material channel where products and order information flow, those companies build a specialized information channel, developed to communicate to those who need it to create demand. Conclusions can be extended to supply chains where products and services are complex and decision makers must be clearly informed about technology-related information. (C) 2009 Elsevier B.V. All rights reserved.