983 resultados para capability data


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This research reports liquid liquid equilibrium data for the system lard (swine fat), cis-9-octadecenoic acid (oleic acid), ethanol, and water at 318.2 K, as well as their correlation with the nonrandom two-liquid (NRTL) and universal quasichemical activity coefficient (UNIQUAC) thermodynamic equations, which have provided global deviations of 0.41 % and 0.53 %, respectively. Additional equilibrium experiments were also performed to obtain cholesterol partition (or distribution) coefficients to verify the availability of the use of ethanol plus water to reduce the cholesterol content in lard. The partition experiments were performed with concentrations of free fatty acids (commercial oleic acid) that varied from (0 to 20) mass % and of water in the solvent that varied from (0 to 18) mass %. The percentage of free fatty acids initially present in lard had a slight effect on the distribution of cholesterol between the phases. Furthermore, the distribution coefficients decreased by adding water in the ethanol; specifically, it resulted in a diminution of the capability of the solvent to remove the cholesterol.

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The main aim of this Ph.D. dissertation is the study of clustering dependent data by means of copula functions with particular emphasis on microarray data. Copula functions are a popular multivariate modeling tool in each field where the multivariate dependence is of great interest and their use in clustering has not been still investigated. The first part of this work contains the review of the literature of clustering methods, copula functions and microarray experiments. The attention focuses on the K–means (Hartigan, 1975; Hartigan and Wong, 1979), the hierarchical (Everitt, 1974) and the model–based (Fraley and Raftery, 1998, 1999, 2000, 2007) clustering techniques because their performance is compared. Then, the probabilistic interpretation of the Sklar’s theorem (Sklar’s, 1959), the estimation methods for copulas like the Inference for Margins (Joe and Xu, 1996) and the Archimedean and Elliptical copula families are presented. In the end, applications of clustering methods and copulas to the genetic and microarray experiments are highlighted. The second part contains the original contribution proposed. A simulation study is performed in order to evaluate the performance of the K–means and the hierarchical bottom–up clustering methods in identifying clusters according to the dependence structure of the data generating process. Different simulations are performed by varying different conditions (e.g., the kind of margins (distinct, overlapping and nested) and the value of the dependence parameter ) and the results are evaluated by means of different measures of performance. In light of the simulation results and of the limits of the two investigated clustering methods, a new clustering algorithm based on copula functions (‘CoClust’ in brief) is proposed. The basic idea, the iterative procedure of the CoClust and the description of the written R functions with their output are given. The CoClust algorithm is tested on simulated data (by varying the number of clusters, the copula models, the dependence parameter value and the degree of overlap of margins) and is compared with the performance of model–based clustering by using different measures of performance, like the percentage of well–identified number of clusters and the not rejection percentage of H0 on . It is shown that the CoClust algorithm allows to overcome all observed limits of the other investigated clustering techniques and is able to identify clusters according to the dependence structure of the data independently of the degree of overlap of margins and the strength of the dependence. The CoClust uses a criterion based on the maximized log–likelihood function of the copula and can virtually account for any possible dependence relationship between observations. Many peculiar characteristics are shown for the CoClust, e.g. its capability of identifying the true number of clusters and the fact that it does not require a starting classification. Finally, the CoClust algorithm is applied to the real microarray data of Hedenfalk et al. (2001) both to the gene expressions observed in three different cancer samples and to the columns (tumor samples) of the whole data matrix.

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The present research aims at shedding light on the demanding puzzle characterizing the issue of child undernutrition in India. Indeed, the so called ‘Indian development paradox’ identifies the phenomenon according to which higher level of income per capita is recorded alongside a lethargic reduction in the proportion of underweight children aged below three years. Thus, in the time period occurring from 2000 to 2005, real Gross Domestic Production per capita has annually grown at 5.4%, whereas the proportion of children who are underweight has declined from 47% to 46%, a mere one point percent. Such trend opens up the space for discussing the traditionally assumed linkage between income-poverty and undernutrition as well as food intervention as the main focus of policies designed to fight child hunger. Also, it unlocks doors for evaluating the role of an alternative economic approach aiming at explaining undernutrition, such as the Capability Approach. The Capability Approach argues for widening the informational basis to account not only for resources, but also for variables related to liberties, opportunities and autonomy in pursuing what individuals value.The econometric analysis highlights the relevance of including behavioral factors when explaining child undernutrition. In particular, the ability of the mother to move freely in the community without the need of asking permission to her husband or mother-in-law is statistically significant when included in the model, which accounts also for confounding traditional variables, such as economic wealth and food security. Also, focusing on agency, results indicates the necessity of measuring autonomy in different domains and the need of improving the measurement scale for agency data, especially with regards the domain of household duties. Finally, future research is required to investigate policy venues for increasing agency in women and in the communities they live in as viable strategy for reducing the plague of child undernutrition in India.

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The thesis objectives are to develop new methodologies for study of the space and time variability of Italian upper ocean ecosystem through the combined use of multi-sensors satellite data and in situ observations and to identify the capability and limits of remote sensing observations to monitor the marine state at short and long time scales. Three oceanographic basins have been selected and subjected to different types of analyses. The first region is the Tyrrhenian Sea where a comparative analysis of altimetry and lagrangian measurements was carried out to study the surface circulation. The results allowed to deepen the knowledge of the Tyrrhenian Sea surface dynamics and its variability and to defined the limitations of satellite altimetry measurements to detect small scale marine circulation features. Channel of Sicily study aimed to identify the spatial-temporal variability of phytoplankton biomass and to understand the impact of the upper ocean circulation on the marine ecosystem. An combined analysis of the satellite of long term time series of chlorophyll, Sea Surface Temperature and Sea Level field data was applied. The results allowed to identify the key role of the Atlantic water inflow in modulating the seasonal variability of the phytoplankton biomass in the region. Finally, Italian coastal marine system was studied with the objective to explore the potential capability of Ocean Color data in detecting chlorophyll trend in coastal areas. The most appropriated methodology to detect long term environmental changes was defined through intercomparison of chlorophyll trends detected by in situ and satellite. Then, Italian coastal areas subject to eutrophication problems were identified. This work has demonstrated that satellites data constitute an unique opportunity to define the features and forcing influencing the upper ocean ecosystems dynamics and can be used also to monitor environmental variables capable of influencing phytoplankton productivity.

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In the era of the Internet of Everything, a user with a handheld or wearable device equipped with sensing capability has become a producer as well as a consumer of information and services. The more powerful these devices get, the more likely it is that they will generate and share content locally, leading to the presence of distributed information sources and the diminishing role of centralized servers. As of current practice, we rely on infrastructure acting as an intermediary, providing access to the data. However, infrastructure-based connectivity might not always be available or the best alternative. Moreover, it is often the case where the data and the processes acting upon them are of local scopus. Answers to a query about a nearby object, an information source, a process, an experience, an ability, etc. could be answered locally without reliance on infrastructure-based platforms. The data might have temporal validity limited to or bounded to a geographical area and/or the social context where the user is immersed in. In this envisioned scenario users could interact locally without the need for a central authority, hence, the claim of an infrastructure-less, provider-less platform. The data is owned by the users and consulted locally as opposed to the current approach of making them available globally and stay on forever. From a technical viewpoint, this network resembles a Delay/Disruption Tolerant Network where consumers and producers might be spatially and temporally decoupled exchanging information with each other in an adhoc fashion. To this end, we propose some novel data gathering and dissemination strategies for use in urban-wide environments which do not rely on strict infrastructure mediation. While preserving the general aspects of our study and without loss of generality, we focus our attention toward practical applicative scenarios which help us capture the characteristics of opportunistic communication networks.

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In the current market system, power systems are operated at higher loads for economic reasons. Power system stability becomes a genuine concern in such operating conditions. In case of failure of any larger component, the system may become stressed. These events may start cascading failures, which may lead to blackouts. One of the main reasons of the major recorded blackout events has been the unavailability of system-wide information. Synchrophasor technology has the capability to provide system-wide real time information. Phasor Measurement Units (PMUs) are the basic building block of this technology, which provide the Global Positioning System (GPS) time-stamped voltage and current phasor values along with the frequency. It is being assumed that synchrophasor data of all the buses is available and thus the whole system is fully observable. This information can be used to initiate islanding or system separation to avoid blackouts. A system separation strategy using synchrophasor data has been developed to answer the three main aspects of system separation: (1) When to separate: One class support machines (OC-SVM) is primarily used for the anomaly detection. Here OC-SVM was used to detect wide area instability. OC-SVM has been tested on different stable and unstable cases and it is found that OC-SVM has the capability to detect the wide area instability and thus is capable to answer the question of “when the system should be separated”. (2) Where to separate: The agglomerative clustering technique was used to find the groups of coherent buses. The lines connecting different groups of coherent buses form the separation surface. The rate of change of the bus voltage phase angles has been used as the input to this technique. This technique has the potential to exactly identify the lines to be tripped for the system separation. (3) What to do after separation: Load shedding was performed approximately equal to the sum of power flows along the candidate system separation lines should be initiated before tripping these lines. Therefore it is recommended that load shedding should be initiated before tripping the lines for system separation.

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In this paper we present the results from the coverage and the orbit determination accuracy simulations performed within the recently completed ESA study “Assessment Study for Space Based Space Surveillance (SBSS) Demonstration System” (Airbus Defence and Space consortium). This study consisted in investigating the capability of a space based optical sensor (SBSS) orbiting in low Earth orbit (LEO) to detect and track objects in GEO (geosynchronous orbit), MEO (medium Earth orbit) and LEO and to determinate and improve initial orbits from such observations. Space based systems may achieve better observation conditions than ground based sensors in terms of astrometric accuracy, detection coverage, and timeliness. The primary observation mode of the proposed SBSS demonstrator is GEO surveillance, i.e. the systematic search and detection of unknown and known objects. GEO orbits are specific and unique orbits from dynamical point of view. A space-based sensor may scan the whole GEO ring within one sidereal day if the orbit and pointing directions are chosen properly. For an efficient survey, our goal was to develop a leak-proof GEO fence strategy. Collaterally, we show that also MEO, LEO and other (GTO,Molniya, etc.) objects would be possible to observe by the system and for a considerable number of LEO objects to down to size of 1 cm we can obtain meaningful statistical data for improvement and validation of space debris environment models

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AIM OF PAPER AND RESEARCH QUESTIONS The primary aim of this investigation was to examine, if tourism in Switzerland can be stimulated by focusing on e-bike offers. Switzerland is an attractive and manifold country for bike tourism. However, there are plenty of hilly and steep areas, where the topography is quite demanding and cycling is predestined to ambitious sportsperson. Less performance-oriented bike tourists are possibly discouraged by the challenges of the landscape. E-bikes seem to be a reasonable alterna-tive to enable less trained person to attend bike tours in steeper regions as well as to keep heterogeneous groups together. E-bikes are already popular in Switzerland for daily routes as the journey to work, but they are not very common in the tour-istic context. The presented investigation evaluates the current standing of supply and demand for e-bike tourism and asks for opportunities and threats in the future development. LITERTURE REVIEW The existing frameworks to analyse capability in the field of sport tourism are limited, because of the broad variation of sports and tourism types. Still several conceptions are valuable to evaluate the opportunities of e-bike tourism in Switzer-land. According to Higham and Hinch (2009) the potential of touristic products and destinations always depends on the interaction among the factors place, people and activity. Standeven and de Knop (1999) support this position by identify-ing the experience of place as a key component of the sport tourism experience. Bull (2005) assumes that place not only affects experience. In his opinion, the specific spatially located resources are even crucial for the existence of nature sports. He identifies four factors determining the attraction of touristic products or destination, as physical characteristics, accessibility and infrastructural arrangements, political and economic resources as well as cultural and perceptual aspects. Concerning the demand side (people) the contemporary research is guided by an individual psychological focus delivering mainly results about motives and the decision making process (e.g. Görtz & Hürten, 2011). RESEARCH DESIGN AND DATA ANALYSIS The presented study is based on a between method triangulation, consisting of qualitative interviews with important stake-holders on the supply side and a cross sectional survey on the demand side. Qualitative interviews were conducted with the first provider of touristic e-bike routes and with the manager of the leading e-bike rental company in Switzerland. The interviews were evaluated by qualitative content analysis according to Mayring (2008). The survey covered a randomized sample of 748 adult persons and focused on interests and needs of potential consumers. The concluding potentials analy-sis combined the results of the interviews and the survey with the findings of literature research. As central outcome the strengths, weaknesses, opportunities and threats were evaluated and presented by SWOT-analysis. RESULTS Results showed that the development of e-bike tourism in Switzerland was not initiated by tourism promoter, but by an innovative e-bike producer. However, also for the manufacturer the fit between landscape (place), product (activity) and visitors (people) was the crucial criterion. The first e-bike tours were offered in a demanding and rural region, in order that the experience of place was able to promote a positive overall experience. Due to the success of the first touristic e-bike products, several tourism regions started to extend their portfolio with e-bike offers. To date a nationwide network for signalised e-bike tours, rental stations and changing stations for rechargeable batteries is established. Despite the attractive offer, the demand is only moderate. The obtained results of the consumer survey pointed at a certain barrier to use e-bikes for tourism activities. The most substantial barrier is the missing affinity for bike tourism in general. Another notable group considering themselves as “fit enough for normal bike tourism”. Nevertheless 55% of the respondent are interested in tour-istic e-bike products. Looking only at people with e-bike tourism experience, even 92% are interested in further activities. DISCUSSION AN CONCLUSION The current study findings are encouraging because they suggest a superior suitability and an attractive level of e-bike tourism products in Switzerland. The results of the consumer survey indicate an increasing demand for e-bike tourism. The investigation also points at some risks, as the rivalry for bike tourism or the raised safety hazard because of the increased driving speed. Summing up, the results support the conclusion, that e-bike tourism will become more important in the com-ing years. However, to reach the goal relevant trends as the requirement for customised offers must be considered and marketing activities are supposed to be extended. REFERENCES Bull, C. (2005). Sport tourism resource analysis. In J. Higham (Ed.), Sport tourism destination: Issues, opportunities and analysis (pp. 25-38). Amsterdam: Elsevier Butterworth-Heinemann. Görtz, M., & D. Hürten (2011). Motive der Radurlauber, psychografische Merkmale und Reiseverhalten. In A. Dreyer, E. Miglbauer & R. Mühlnickel (Hrsg.), Radtourismus. Entwicklungen, Potenziale, Perspektiven (S. 36-43). München: Olden-bourg. Higham, J., & Hinch, T. (2009). Sport and Tourism. Globalization, Mobility and Identity. Amsterdam: Butterworth-Heinemann. Mayring, P. (2008). Qualitative Inhaltsanalyse. Grundlagen und Techniken (10. Aufl.). Weinheim: Beltz Verlag. Standeven, J., & De Knop, P. (1999). Sport Tourism. Campaign: Human Kinetics.

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Every x-ray attenuation curve inherently contains all the information necessary to extract the complete energy spectrum of a beam. To date, attempts to obtain accurate spectral information from attenuation data have been inadequate.^ This investigation presents a mathematical pair model, grounded in physical reality by the Laplace Transformation, to describe the attenuation of a photon beam and the corresponding bremsstrahlung spectral distribution. In addition the Laplace model has been mathematically extended to include characteristic radiation in a physically meaningful way. A method to determine the fraction of characteristic radiation in any diagnostic x-ray beam was introduced for use with the extended model.^ This work has examined the reconstructive capability of the Laplace pair model for a photon beam range of from 50 kVp to 25 MV, using both theoretical and experimental methods.^ In the diagnostic region, excellent agreement between a wide variety of experimental spectra and those reconstructed with the Laplace model was obtained when the atomic composition of the attenuators was accurately known. The model successfully reproduced a 2 MV spectrum but demonstrated difficulty in accurately reconstructing orthovoltage and 6 MV spectra. The 25 MV spectrum was successfully reconstructed although poor agreement with the spectrum obtained by Levy was found.^ The analysis of errors, performed with diagnostic energy data, demonstrated the relative insensitivity of the model to typical experimental errors and confirmed that the model can be successfully used to theoretically derive accurate spectral information from experimental attenuation data. ^

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Problems due to the lack of data standardization and data management have lead to work inefficiencies for the staff working with the vision data for the Lifetime Surveillance of Astronaut Health. Data has been collected over 50 years in a variety of manners and then entered into a software. The lack of communication between the electronic health record (EHR) form designer, epidemiologists, and optometrists has led to some level to confusion on the capability of the EHR system and how its forms can be designed to fit all the needs of the relevant parties. EHR form customizations or form redesigns were found to be critical for using NASA's EHR system in the most beneficial way for its patients, optometrists, and epidemiologists. In order to implement a protocol, data being collected was examined to find the differences in data collection methods. Changes were implemented through the establishment of a process improvement team (PIT). Based on the findings of the PIT, suggestions have been made to improve the current EHR system. If the suggestions are implemented correctly, this will not only improve efficiency of the staff at NASA and its contractors, but set guidelines for changes in other forms such as the vision exam forms. Because NASA is at the forefront of such research and health surveillance the impact of this management change could have a drastic improvement on the collection of and adaptability of the EHR. Accurate data collection from this 50+ year study is ongoing and is going to help current and future generations understand the implications of space flight on human health. It is imperative that the vast amount of information is documented correctly.^

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For a reliable simulation of the time and space dependent CO2 redistribution between ocean and atmosphere an appropriate time dependent simulation of particle dynamics processes is essential but has not been carried out so far. The major difficulties were the lack of suitable modules for particle dynamics and early diagenesis (in order to close the carbon and nutrient budget) in ocean general circulation models, and the lack of an understanding of biogeochemical processes, such as the partial dissolution of calcareous particles in oversaturated water. The main target of ORFOIS was to fill in this gap in our knowledge and prediction capability infrastructure. This goal has been achieved step by step. At first comprehensive data bases (already existing data) of observations of relevance for the three major types of biogenic particles, organic carbon (POC), calcium carbonate (CaCO3), and biogenic silica (BSi or opal), as well as for refractory particles of terrestrial origin were collated and made publicly available.

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Sexual segregation in habitat use occurs in a number of animal species, including southern elephant seals, where differences in migration localities and dive behaviour between sexes have been recorded. Due to the extreme sexual size dimorphism exhibited by southern elephant seals, it is unclear whether observed differences in dive behaviour are due to increased physiological capacity of males, compared to females, or differences in activity budgets and foraging behaviour. Here we use a mixed-effects modelling approach to investigate the effects of sex, size, age and individual variation on a number of dive parameters measured on southern elephant seals from Marion Island. Although individual variation accounted for substantial portions of total model variance for many response variables, differences in maximum and targeted dive depths were always influenced by sex, and only partly by body length. Conversely, dive durations were always influenced by body length, while sex was not identified as a significant influence. These results support hypotheses that physiological capability associated with body size is a limiting factor on dive durations. However, differences in vertical depth use appear to be the result of differences in forage selection between sexes, rather than a by-product of the size dimorphism displayed by this species. This provides further support for resource partitioning and possible avoidance of inter-sexual competition in southern elephant seals.

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In 2008, the 50th anniversary of the IGY (International Geophysical Year), WDCMARE presents with this CD publication 3632 data sets in Open Access as part of the most important results from 73 cruises of the research vessel METEOR between 1964 and 1985. The archive is a coherent organized collection of published and unpublished data sets produced by scientists of all marine research disciplines who participated in Meteor expeditions, measured environmental parameters during cruises and investigated sample material post cruise in the labs of the participating institutions. In most cases, the data was gathered from the Meteor Forschungsergebnisse, published by the Deutsche Forschungsgemeinschaft (DFG). A second important data source are time series and radiosonde ascensions of more than 20 years of ships weather observations, which were provided by the Deutscher Wetterdienst, Hamburg. The final inclusion of all data into the PANGAEA information system ensures secure archiving, future updates, widespread distribution in electronic, machine-readable form with longterm access via the Internet. To produce this publication, all data sets with metadata were extracted from PANGAEA and organized in a directory structure on a CD together with a search capability.

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We are investigating the performances of a data acquisition system for Time of Flight PET, based on LYSO crystal slabs and 64 channels Silicon Photomultipliers matrices (1.2 cm2 of active area each). Measurements have been performed to test the timing capability of the detection system (SiPM matices coupled to a LYSO slab and the read-out electronics) with both test signal and radioactive source.