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91.
92.
Martín-Guerrero JD Camps-Valls G Soria-Olivas E Serrano-López AJ Pérez-Ruixo JJ Jiménez-Torres NV 《IEEE transactions on bio-medical engineering》2003,50(10):1136-1142
The external administration of recombinant human erythropoietin is the chosen treatment for those patients with secondary anemia due to chronic renal failure in periodic hemodialysis. The objective of this paper is to carry out an individualized prediction of the EPO dosage to be administered to those patients. The high cost of this medication, its side-effects and the phenomenon of potential resistance which some individuals suffer all justify the need for a model which is capable of optimizing dosage individualization. A group of 110 patients and several patient factors were used to develop the models. The support vector regressor (SVR) is benchmarked with the classical multilayer perceptron (MLP) and the Autoregressive Conditional Heteroskedasticity (ARCH) model. We introduce a priori knowledge by relaxing or tightening the epsilon-insensitive region and the penalization parameter depending on the time period of the patients' follow-up. The so-called profile-dependent SVR (PD-SVR) improves results of the standard SVR method and the MLP. We perform sensitivity analysis on the MLP and inspect the distribution of the support vectors in the input and feature spaces in order to gain knowledge about the problem. 相似文献
93.
José R. Sendra Javier del Pino Antonio Hernández Benito González Javier García Andrés García-Alonso Antonio Nunez 《Analog Integrated Circuits and Signal Processing》2003,35(2-3):121-132
In this work we propose a modification to the conventional lumped equivalent circuit model for integrated inductors. Also the widely used parametric model is modified. The proposed models expand the frequency range where the integrated inductor behavior is accurately predicted. They are useful in developing automatic tools to assist the designers in selecting and automatically laying-out integrated inductors [1]. This work is based on measurements from integrated inductors fabricated in a standard silicon process. 相似文献
94.
PbS/CdS/ZnS Quantum Dots: A Multifunctional Platform for In Vivo Near‐Infrared Low‐Dose Fluorescence Imaging 下载免费PDF全文
Antonio Benayas Fuqiang Ren Elisa Carrasco Vicente Marzal Blanca del Rosal Belete A. Gonfa Ángeles Juarranz Francisco Sanz‐Rodríguez Daniel Jaque José García‐Solé Dongling Ma Fiorenzo Vetrone 《Advanced functional materials》2015,25(42):6650-6659
Over the past decade, near‐infrared (NIR)‐emitting nanoparticles have increasingly been investigated in biomedical research for use as fluorescent imaging probes. Here, high‐quality water‐dispersible core/shell/shell PbS/CdS/ZnS quantum dots (hereafter QDs) as NIR imaging probes fabricated through a rapid, cost‐effective microwave‐assisted cation exchange procedure are reported. These QDs have proven to be water dispersible, stable, and are expected to be nontoxic, resulting from the growth of an outer ZnS shell and the simultaneous surface functionalization with mercaptopropionic acid ligands. Care is taken to design the emission wavelength of the QDs probe lying within the second biological window (1000–1350 nm), which leads to higher penetration depths because of the low extinction coefficient of biological tissues in this spectral range. Furthermore, their intense fluorescence emission enables to follow the real‐time evolution of QD biodistribution among different organs of living mice, after low‐dose intravenous administration. In this paper, QD platform has proven to be capable (ex vivo and in vitro) of high‐resolution thermal sensing in the physiological temperature range. The investigation, together with the lack of noticeable toxicity from these PbS/CdS/ZnS QDs after preliminary studies, paves the way for their use as outstanding multifunctional probes both for in vitro and in vivo applications in biomedicine. 相似文献
95.
Isaac Seoane Gerson Rodríguez de los Santos José Alberto Hernández Manuel Urueña Ricardo Romeral Ángel Cuevas David Larrabeiti 《Photonic Network Communications》2011,21(3):278-287
In Tunable-Transmitter Fixed-Receiver (TT-FR)-based Wavelength Division Multiplexed (WDM) ring topologies, each node is provided
with a dedicated wavelength (home channel) for reception, which must be shared by the upstream nodes willing to communicate
with it. Thus, to avoid channel collisions, it is necessary to define a Medium Access Control (MAC) mechanism that arbitrates
access to a given destination wavelength. This work proposes and analyses a simple MAC mechanism that avoids channel collisions
by recirculating traffic on the upstream ring segment where congestion was detected. Essentially, whenever a given node has
got any traffic to transmit, it must first block access to in-transit traffic, which is reflected back to the upstream node
over a second optical fibre. Such blocked traffic is given a second chance to pass through the congested node after a round
segment delay, thus making use of the ring topology as buffering units. This work analyses the performance operation of such
a MAC protocol under two policies applied to recirculated traffic: (1) recirculation bypass and (2) recirculation store-and-forward. 相似文献
96.
José M. del Álamo Antonio M. Fernández Rubén Trapero Juan C. Yelmo Miguel A. Monjas 《Mobile Networks and Applications》2011,16(4):446-459
The subscribers’ personal information and services that mobile operators are able to provide to Web developers offer new and
exciting possibilities in numerous domains. However, bringing mobile information services to the Web to enable a new generation
of mobile Web services presents several research challenges on identity and privacy management. In this paper, we describe
a framework for identity management in mobile services that empowers users to govern the use and release of their personal
information. Our framework is based on a brokering approach that intermediates between the mobile operator’s information services
and the Web service providers. By leveraging on Web services, identity management infrastructure and privacy enhancing technologies,
our framework provides an effective, privacy-considerate delivery of services over the mobile Web environment. This paper
describes the design principles and architecture of the framework as well as the feasibility, applicability and user-experience
evaluation we have carried out. 相似文献
97.
Laslo Babinszky Jos M Van Der Meer Hugh Boer Leo A Den Hartog 《Journal of the science of food and agriculture》1990,50(2):173-178
An in-vitro method using commercially available enzymes for the prediction of the in-vivo digestible crude protein content was developed and tested on seven feedstuffs and 16 diets for pigs. Fat-extracted feed samples were consecutively incubated with pepsin at pH 1 and pancreatin at pH 6.8. From the nitrogen content of the feed sample and of the residue after incubation the in-vitro digestibility of the crude protein was calculated. Using the linear regression of in-vitro on in-vivo digestible crude protein of samples obtained in feeding trials, the in-vivo digestible crude protein content (DXPp) in g kg?1 dry matter could be predicted. For feedstuffs and diets the correlation was 0.99 and 0.95 and the residual standard deviation 17 and 6 g kg?1 dry matter, respectively. In a similar procedure the nitrogen solubilised during incubation with enzymes was analysed. The regression value was similar to that of the original procedure. However, this procedure was abandoned because it was more laborious. 相似文献
98.
José Craveirinha João Clímaco Lúcia Martins Carlos G. da Silva Nuno Ferreira 《Telecommunication Systems》2013,52(1):203-215
The MPLS platform enables the implementation of advanced multipath and multicast routing schemes. This work develops and analyses the performance of a new bi-criteria minimum spanning tree model intended for routing broadcast messages in MPLS networks or constructing tree-based overlay networks. The aim of the model is to obtain spanning trees which are compromise solutions with respect to two important traffic engineering metrics: load balancing cost and average delay bound. An exact solution to the formulated bi-criteria optimization problem is presented, which is based on an algorithm that enables the computation of the set of supported non-dominated spanning trees. An application model and a set of experiments on randomly generated Internet type topologies will also be presented. Finally a network performance analysis of the model considering three network performance metrics will be shown. 相似文献
99.
A Complete Separation of Hexane Isomers by a Functionalized Flexible Metal Organic Framework 下载免费PDF全文
Patricia A. P. Mendes Patricia Horcajada Sébastien Rives Hong Ren Alírio E. Rodrigues Thomas Devic Emmanuel Magnier Philippe Trens Hervé Jobic Jacques Ollivier Guillaume Maurin Christian Serre José A. C. Silva 《Advanced functional materials》2014,24(48):7666-7673
The separation ability of branched alkane isomers (nHEX, 3MP, 22DMB) of the flexible and functionalized microporous iron(III) dicarboxylate MIL‐53(Fe)‐(CF3)2 solid is evaluated through a combination of breakthrough experiments (binary or ternary mixtures), adsorption isotherms, X‐ray diffraction temperature analysis, quasi‐elastic neutron scattering measurements and molecular dynamics simulations. A kinetically controlled molecular sieve separation between the di‐branched isomer of hexane 22DMB from a mixture of paraffins is achieved. The reported total separation between mono‐ and di‐branched alkanes which was neither predicted nor observed so far in any class of porous solids is spectacular and paves the way towards a potential unprecedented upgrading of the RON of gasoline. 相似文献
100.
Manel Guerrero-Zapata Ruken Zilan José M. Barceló-Ordinas Kemal Bicakci Bulent Tavli 《Telecommunication Systems》2010,45(1):77-91
This is a position paper on our views on security aspects of Wireless Multimedia Sensor Networks (Secure WMSNs). It is meant
to serve as a brief survey. But, more importantly, it gives a perspective on how we foresee the future of this research area,
its main challenges, and its future trends. We believe that this paper will spur new discussions and research ideas among
the researchers from both the industry and the academic world. 相似文献