877 resultados para system selection and implementation


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The advancements in medical science and technology have proved to be a boon to mankind. At the same time they have raised numerous challenges before the legal systems of the world. One such advancement is that of assisted human reproductive technologies and particularly surrogacy, which have given a new meaning to the concept of procreation. These technologies have made it possible for individuals to beget a genetically related child with the help of a third party and without sexual intercourse. Among all the assisted human reproductive technologies, the practice of surrogacy, in which women agree to have their bodies used to undergo a pregnancy and give birth to a baby for another, has raised various legal and human right controversies and diverse legal responses all over the world. India has particularly become a top destination for individuals who wish to beget a child through surrogacy and hence it is imperative for the Indian government to address the challenges posed by surrogacy. This study is an attempt to examine the need and importance of surrogacy practices and the conflicting legal and human rights issues raised by surrogacy in contemporary times. It also examines the adequacy of existing legal framework in India and attempts to provide pragmatic solutions for regulating surrogacy and protecting the interests of various stakeholders involved in surrogacy.

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1. Genomewide association studies (GWAS) enable detailed dissections of the genetic basis for organisms' ability to adapt to a changing environment. In long-term studies of natural populations, individuals are often marked at one point in their life and then repeatedly recaptured. It is therefore essential that a method for GWAS includes the process of repeated sampling. In a GWAS, the effects of thousands of single-nucleotide polymorphisms (SNPs) need to be fitted and any model development is constrained by the computational requirements. A method is therefore required that can fit a highly hierarchical model and at the same time is computationally fast enough to be useful. 2. Our method fits fixed SNP effects in a linear mixed model that can include both random polygenic effects and permanent environmental effects. In this way, the model can correct for population structure and model repeated measures. The covariance structure of the linear mixed model is first estimated and subsequently used in a generalized least squares setting to fit the SNP effects. The method was evaluated in a simulation study based on observed genotypes from a long-term study of collared flycatchers in Sweden. 3. The method we present here was successful in estimating permanent environmental effects from simulated repeated measures data. Additionally, we found that especially for variable phenotypes having large variation between years, the repeated measurements model has a substantial increase in power compared to a model using average phenotypes as a response. 4. The method is available in the R package RepeatABEL. It increases the power in GWAS having repeated measures, especially for long-term studies of natural populations, and the R implementation is expected to facilitate modelling of longitudinal data for studies of both animal and human populations.

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Natural selection mediated by pollinators has influenced the evolution of floral diversity of the flowering plants (angiosperms). The scope of this thesis was to study: 1) phenotypic selection, 2) mating systems, and 3) floral shifts involved in plant speciation. Model plant species were Platanthera bifolia and P. chlorantha (Orchidaceae). These orchids are moth-pollinated, strictly co-sexual (bisexual flowers), and produce a spike that displays 10-20 white flowers. I explored the influence of characters on plant fitness by using multiple linear regressions. Pollen removal (male fitness) and fruit set (female fitness) increased with more flowers per plant in three P. bifolia populations. There was selection towards longer spurs in a dry year when average spur length was shorter than in normal-wet years. Female function was sensitive to drought, which enabled an application of the male function hypothesis of floral evolution (Bateman's principle). The results show that selection may vary between populations, years, and sex-functions. I examined inbreeding by estimating levels of geitonogamy (self-pollination between flowers of an individual) with an emasculation method in two P. bifolia populations. Geitonogamy did not vary with inflorescence size. Levels of geitonogamy was 20-40% in the smaller, but non-significant in the larger population. This may relate to lower number of possible mates and pollinator activity in the smaller population. Platanthera bifolia exhibits the ancestral character state of tongue-attachment of pollinia on the pollinator. Its close relative P. chlorantha attaches its pollinia onto the pollinator's eyes. To explore the mechanism of a floral shift, pollination efficiency and speed was compared between the two species. The results showed no differences in pollination efficiency, but P. chlorantha had faster pollen export and import. Efficiency of pollination in terms of speed may cause floral shifts, and thus speciation.

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In this paper, we examine the on-the-ground realities of upstream-downstream negotiations and transactions over ecosystem services. We explore the engagement, negotiation, implementation, and postimplementation phases of a “reciprocal water access” (RWA) agreement between village communities and municipal water users at Palampur, Himachal Pradesh, India. We aim to highlight how external actors drove the payments for ecosystem services agenda through a series of facilitation and research engagements, which were pivotal to the RWA’s adoption, and how the agreement fared once external agents withdrew. In the postimplementation period, the RWA agreement continues to be upheld by upstream communities amidst evolving, competing land-use changes and claims. The introduction of cash payments for environmental services for forest-water relationships has given rise to multifaceted difficulties for the upstream hamlets, which has impeded the functionality of their forest management committee. Upstream communities’ formal rights and abilities to control and manage their resources are dynamic and need strengthening and assurance; these developments result in fluctuating transaction and opportunity costs not originally envisaged by the RWA agreement. The paper demonstrates the importance of an explicit understanding of the local politics of negotiation and implementation to determine the effectiveness of compensation-based mechanisms for the supply of ecosystem services.

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Adaptive management has been defined and redefined in the context of natural resource management, yet there are few examples of its successful application in ecological restoration. Although the 2009 Delta Reform Act now legally requires adaptive management for all restoration efforts in the Sacramento-San Joaquin Delta, in California, USA, projects in this region still encounter problems with implementation. We used a comparative case study analysis to examine adaptive management planning and implementation both in and around the Delta, assessing not only why adaptive management is not yet well implemented, but also what changes can be made to facilitate the adaptive management approach without sacrificing scientific rigor. Adaptive management seems to be directly and indirectly affected by a variety of challenges and convoluted by ambiguity in both planning documents and practitioner’s interpretations of the concept. Addressing these challenges and ambiguities at the project level may facilitate the adaptive management process and help make it more accessible to practitioners.

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The work presented in my thesis addresses the two cornerstones of modern astronomy: Observation and Instrumentation. Part I deals with the observation of two nearby active galaxies, the Seyfert 2 galaxy NGC 1433 and the Seyfert 1 galaxy NGC 1566, both at a distance of $\sim10$ Mpc, which are part of the Nuclei of Galaxies (NUGA) sample. It is well established that every galaxy harbors a super massive black hole (SMBH) at its center. Furthermore, there seems to be a fundamental correlation between the stellar bulge and SMBH masses. Simulations show that massive feedback, e.g., powerful outflows, in Quasi Stellar Objects (QSOs) has an impact on the mutual growth of bulge and SMBH. Nearby galaxies follow this relation but accrete mass at much lower rates. This gives rise to the following questions: Which mechanisms allow feeding of nearby Active Galactic Nuclei (AGN)? Is this feeding triggered by events, e.g., star formation, nuclear spirals, outflows, on $\sim500$ pc scales around the AGN? Does feedback on these scales play a role in quenching the feeding process? Does it have an effect on the star formation close to the nucleus? To answer these questions I have carried out observations with the Spectrograph for INtegral Field Observation in the Near Infrared (SINFONI) at the Very Large Telescope (VLT) situated on Cerro Paranal in Chile. I have reduced and analyzed the recorded data, which contain spatial and spectral information in the H-band ($1.45 \mic-1.85 \mic$) and K-band ($1.95 \mic-2.45 \mic$) on the central $10\arcsec\times10\arcsec$ of the observed galaxies. Additionally, Atacama Large Millimeter/Sub-millimeter Array (ALMA) data at $350$ GHz ($\sim0.87$ mm) as well as optical high resolution Hubble Space Telescope (HST) images are used for the analysis. For NGC 1433 I deduce from comparison of the distributions of gas, dust, and intensity of highly ionized emission lines that the galaxy center lies $\sim70$ pc north-northwest of the prior estimate. A velocity gradient is observed at the new center, which I interpret as a bipolar outflow, a circum nuclear disk, or a combination of both. At least one dust and gas arm leads from a $r\sim200$ pc ring towards the nucleus and might feed the SMBH. Two bright warm H$_2$ gas spots are detected that indicate hidden star formation or a spiral arm-arm interaction. From the stellar velocity dispersion (SVD) I estimate a SMBH mass of $\sim1.74\times10^7$ \msol. For NGC 1566 I observe a nuclear gas disk of $\sim150$ pc in radius with a spiral structure. I estimate the total mass of this disk to be $\sim5.4\times10^7$ \msol. What mechanisms excite the gas in the disk is not clear. Neither can the existence of outflows be proven nor is star formation detected over the whole disk. On one side of the spiral structure I detect a star forming region with an estimated star formation rate of $\sim2.6\times10^{-3}$ \msol\ yr$^{-1}$. From broad Br$\gamma$ emission and SVD I estimate a mean SMBH mass of $\sim5.3\times10^6$ \msol\ with an Eddington ratio of $\sim2\times10^{-3}$. Part II deals with the final tests of the Fringe and Flexure Tracker (FFTS) for LBT INterferometric Camera and the NIR/Visible Adaptive iNterferometer for Astronomy (LINC-NIRVANA) at the Large Binocular Telescope (LBT) in Arizona, USA, which I conducted. The FFTS is the subsystem that combines the two separate beams of the LBT and enables near-infrared interferometry with a significantly large field of view. The FFTS has a cryogenic system and an ambient temperature system which are separated by the baffle system. I redesigned this baffle to guarantee the functionality of the system after the final tests in the Cologne cryostat. The redesign did not affect any scientific performance of LINC-NIRVANA. I show in the final cooldown tests that the baffle fulfills the temperature requirement and stays $<110$ K whereas the moving stages in the ambient system stay $>273$ K, which was not given for the old baffle design. Additionally, I test the tilting flexure of the whole FFTS and show that accurate positioning of the detector and the tracking during observation can be guaranteed.

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Työssä arvioidaan ja verifioidaan puheluiden luokitteluun suunniteltu Call Sequence Analysing Algorithm (CSA-algoritmi). Algoritmin tavoitteena on luokitella riittävän samankaltaiset puhelut ryhmiksi tarkempaa vika-analyysia varten. Työssä esitellään eri koneoppimisalgoritmien pääluokitukset ja niiden tyypilliset eroavaisuudet, eri luokitteluprosesseille ominaiset datatyypit, sekä toimintaympäristöt, joissa kyseinen toteutus on suunniteltu toimivaksi. CSA-algoritmille syötetään verkon ylläpitoviesteistä koostuvia viestisarjoja, joiden sisällön perusteella samankaltaiset sarjat ryhmitellään kokonaisuuksiksi. Algoritmin suorituskykyä arvioidaan 94 käsin luokitellun verrokkisarjan avulla. Sarjat on kerätty toimivasta 3G-verkon kontrollerista. Kahta sarjaa vertailemalla sarjaparille muodostetaan keskinäinen tunnusluku: sarjojen samanlaisuutta kuvaava etäisyys. Tässä työssä keskitytään erityisesti Hamming-etäisyyteen. Etäisyyden avulla sarjat koostetaan ryhmiksi. Muuttamalla hyväksyttävää maksimietäisyyttä, jonka perusteella kaksi sarjaa lasketaan kuuluvaksi samaan ryhmään, saadaan aikaiseksi alaryhmiä, joihin kuuluu ainoastaan samankaltaisia sarjoja. Hyväksyttävän etäisyyden kasvaessa, myös virheluokitusten määrä kasvaa. Oikeiden lajittelutulosten vertailukohteena toimii käsin luokiteltu ryhmittely. CSA-algoritmin luokittelutuloksen tarkkuus esitetään prosentuaalisena osuutena tavoiteryhmittelystä maksimietäisyyden funktiona. Työssä osoitetaan, miten etäisyysattribuutiksi valittu Hamming-etäisyys ei sovellu tämän datan luokitteluun. Työn lopussa ehdotetaan menetelmää ja työkalua, joiden avulla useampaa eri lajittelija-algoritmia voidaan testata nopealla kehityssyklillä.

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Scientific applications rely heavily on floating point data types. Floating point operations are complex and require complicated hardware that is both area and power intensive. The emergence of massively parallel architectures like Rigel creates new challenges and poses new questions with respect to floating point support. The massively parallel aspect of Rigel places great emphasis on area efficient, low power designs. At the same time, Rigel is a general purpose accelerator and must provide high performance for a wide class of applications. This thesis presents an analysis of various floating point unit (FPU) components with respect to Rigel, and attempts to present a candidate design of an FPU that balances performance, area, and power and is suitable for massively parallel architectures like Rigel.

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This thesis intends to analyse the performance and the efficiency of companies and to identify the key factors that may explain it. A comprehensive analysis based on a set of economic and financial ratios was studied as an instrument which provides information on enterprise performance and its efficiency. It was selected a sample with 15 enterprises: 7 Portuguese and 8 Ukrainian ones, belonging to several industries. Financial and non-financial data was collected for 6 years, during the period of 2009 to 2014. Research questions that guided this work were: Are the enterprises efficient/profitable? What factors influence enterprises’ efficiency/performance? Is there any difference between Ukrainian and Portuguese enterprises’ efficiency/performance, which factors have more influence? Which industrial sector is represented by more efficient/profitable enterprises? The main results showed that in average enterprises were efficient; comparing by states Ukrainian enterprises are more efficient; industries have similar level of efficiency. Among factors that influence ATR positively are fixed and current assets turnover ratios, ROA; negatively influencing are EBITDA margin and liquidity ratio. There is no significant difference between models by country. Concerning profitability, enterprises have low performance level but in comparison of countries Ukrainian enterprises have better profitability in average. Regarding the industry sector, paper industry is the most profitable. Among factors influencing ROA are profit margin, fixed asset turnover ratio, EBITDA margin, Debt to equity ratio and the country. In case of profitability both countries have different models. For Ukrainian enterprises is suggested to pay attention on factors of Short-term debt to total debt, ROA, Interest coverage ratio in order to be more efficient; Profit margin and EBITDA margin to make their performance better. For Portuguese enterprises for improving efficiency the observation and improvement of fixed assets turnover ratio, current assets turnover ratio, Short-term financial debt to total debt, Leverage Ratio, EBITDA margin is suggested; for improving higher profitability track fixed assets turnover ratio, current assets turnover ratio, Debt to equity ratio, Profit margin and Interest coverage ratio is suggested.