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排序方式: 共有169条查询结果,搜索用时 15 毫秒
81.
Alexander Berler Sotiris Pavlopoulos Dimitris Koutsouris 《IEEE transactions on information technology in biomedicine》2005,9(2):184-192
The advantages of the introduction of information and communication technologies in the complex health-care sector are already well-known and well-stated in the past. It is, nevertheless, paradoxical that although the medical community has embraced with satisfaction most of the technological discoveries allowing the improvement in patient care, this has not happened when talking about health-care informatics. Taking the above issue of concern, our work proposes an information model for knowledge management (KM) based upon the use of key performance indicators (KPIs) in health-care systems. Based upon the use of the balanced scorecard (BSC) framework (Kaplan/Norton) and quality assurance techniques in health care (Donabedian), this paper is proposing a patient journey centered approach that drives information flow at all levels of the day-to-day process of delivering effective and managed care, toward information assessment and knowledge discovery. In order to persuade health-care decision-makers to assess the added value of KM tools, those should be used to propose new performance measurement and performance management techniques at all levels of a health-care system. The proposed KPIs are forming a complete set of metrics that enable the performance management of a regional health-care system. In addition, the performance framework established is technically applied by the use of state-of-the-art KM tools such as data warehouses and business intelligence information systems. In that sense, the proposed infrastructure is, technologically speaking, an important KM tool that enables knowledge sharing amongst various health-care stakeholders and between different health-care groups. The use of BSC is an enabling framework toward a KM strategy in health care. 相似文献
82.
纤维缠绕环形容器可充分利用空间,节省结构质量和消除系统质心漂移,目前在很多工业领域中发挥着日益重要的作用。本文基于复合材料层合理论和测地线缠绕原理,提出了纤维缠绕环形压力容器的线型优化设计方法。应用微分几何,导出了圆环面上测地缠绕轨迹和纤维不架空判据。以初始缠绕角和缠绕层厚度为变量,对结构重量进行最小化设计,得到了对应于不同管径比的优化缠绕线型。对优化线型进行了计算机缠绕仿真,并给出了缠绕铺层的各向正轴应力分布。结果表明,优化设计的缠绕线型模式精确可靠,满足纤维缠绕的基本要求。纤维缠绕角度大小更趋于合理,从而能充分发挥缠绕结构的力学性能,减经系统重量,使优化得到的环形容器结构性能比传统测地线缠绕环形容器有很大提高。本文的设计计算方法可直接用于复合材料环形气瓶的初步设计。 相似文献
83.
Takao Tani Naoyoshi Watanabe Kazumasa Takatori Sotiris E. Pratsinis 《Journal of the American Ceramic Society》2003,86(6):898-904
Various oxide powders were prepared by the emulsion combustion method (ECM) using metal precursors, kerosene, and a surfactant. The product particles were characterized by transmission electron microscopy (TEM), nitrogen adsorption, and X-ray diffraction. Hollow γ-Al2 O3 particles were produced from aluminum nitrate or chloride precursors dispersed in air, whereas dispersion of the precursor emulsion in oxygen resulted in solid α-Al2 O3 particles. Hollow spheres were obtained also for TiO2 , ZrO2 , and Y2 O3 by ECM of TiCl4 , zirconium oxynitrate, and yttrium nitrate in aqueous solution. A simple method was developed to predict the thickness and diameter of hollow particles using the nitrogen adsorption data and initial droplet concentration of the ECM spray. The TEM diameter and shell thickness of hollow particles were consistent with those predicted. In contrast, solid particles were formed by ECM for ZnO, Fe2 O3 , CeO2 , and MgO from aqueous solutions of their corresponding nitrates. 相似文献
84.
Jinsoo Kim Oliver Wilhelm Sotiris E. Pratsinis 《Journal of the American Ceramic Society》2001,84(12):2802-2808
Porous titania granules (1–20 μm) were made by spray drying titania solutions with and without peptization. An unpeptized titania slurry was prepared by hydrolyzing titanium tetraisopropoxide, while a peptized sol was prepared by adding nitric acid to the slurry. The characteristics of the granules depended on the feed solution properties. In particular, granules from the unpeptized slurry showed a bimodal pore size distribution (PSD), with a rough surface attributed to hard aggregates; granules from the peptized sol showed a monomodal PSD, with a smooth surface of well-packed nanoparticles. The effect of dopants (alumina and zirconia) also was investigated. Doping slowed the crystallite growth of the titania granules, as well as the anatase-to-rutile phase transformation. All of the peptized granules exhibited a monomodal PSD of intraparticle pores, from 2 to 15 nm. However, the PSD of the pure titania granules collapsed at 600°C, mainly by phase transformation. 相似文献
85.
86.
Stefano Alcaro Prof. Anna Artese Dr. James N. Iley Prof. Sotiris Missailidis Prof. Francesco Ortuso Dr. Lucia Parrotta Dr. Raffaele Pasceri Dr. Francesco Paduano Dr. Claudia Sissi Prof. Francesco Trapasso Dr. Maria Gabriella Vigorita Prof. 《ChemMedChem》2010,5(4):575-583
Molecular modeling studies carried out with experimental DNA models with the sequence d[AG3(T2AG3)3] suggest that the introduction of a net positive charge onto the side chain of a series of fluorenone carboxamides can improve G‐quadruplex binding. The terminal morpholino moiety was replaced with a novel N‐methylmorpholinium cation starting from two 4‐carboxamide compounds. A different substitution on the fluorenone ring was also investigated and submitted to the same quaternarization process. All compounds were analyzed for their DNA binding properties by competition dialysis methods. In vitro antiproliferative tests were carried out against two different tumor cell lines. Docking experiments were conducted by including all four known human repeat unit G‐quadruplex DNA sequences (27 experimentally determined conformations) against the most active fluorenone derivatives. The results of theoretical, biophysical, and in vitro experiments indicate two novel derivatives as lead compounds for the development of a new generation of G‐quadruplex ligands with greater potency and selectivity. 相似文献
87.
Yun Xiong Shirley W Lyons Toivo T. Kodas Sotiris E. Pratsinis 《Journal of the American Ceramic Society》1995,78(9):2490-2496
The role of particle evaporation during synthesis of volatile metal oxide powders (Bi2 O3 , MoO3 , PbO, and V2 O5 ) by aerosol decomposition (spray pyrolysis) in a heated flow reactor was investigated. Solid particles (0.1–0.6 (Am) of predominantly β-Bi2 O3 were formed with smooth spherical shape at all reactor temperatures (673–1173 K) employed. Solid MoO3 particles (0.1–1.2 μm) produced at low temperatures (673–773 K) had a roughly spherical or faceted morphology and at high temperatures (873 K) had a platelike or layered structure. Solid V2 O5 particles produced at low temperatures (573–673 K) were spherical and at high temperatures (973–1073 K) were platelike. The PbO particles were solid and spherical for all temperatures studied (773°–1073°C). Evaporative losses of up to 100% to the reactor walls were observed for all the metal oxides, due to their substantial vapor pressures. The evaporative losses were modeled by considering simultaneous particle evaporation and mass transfer of the metal oxide vapor to the reactor walls. The calculations indicated that, for most of these volatile metal oxides, evaporative losses were limited by diffusional transport of the vapor to the reactor walls and that evaporative losses occur when the vapor pressure of the oxides in the reactor is above 10-5 -10-3 mm Hg. 相似文献
88.
M. Kamal Akhtar Sotiris E. Pratsinis Sebastian V. R. Mastrangelo 《Journal of the American Ceramic Society》1992,75(12):3408-3416
Gas-phase synthesis of titania by TiCl4 oxidation in the presence of dopants (SiCl4 , POCl3 , and BCl3 ) was investigated in an aerosol reactor as a function of temperature (1300–1700 K) and dopant concentration (0–25 mol% of TiCl4 ). The addition of dopants, most notably silicon and phosphorus, drastically altered the morphology of titania particles from polyhedral to spheroidal, increased the extent of aggregation, increased the specific surface area, reduced the primary particle size, and decreased the rutile content. The observed morphology/crystallinity changes were explained in terms of ionic radii and valence of the dopant element. 相似文献
89.
90.
Ioannis Chatzigiannakis Athanasios Kinalis Sotiris Nikoletseas 《Theory of Computing Systems》2008,42(1):42-72
We introduce a new modelling assumption for wireless sensor networks, that of node redeployment (addition of sensor devices during protocol evolution) and we extend the modelling assumption of heterogeneity (having sensor devices of various types). These two features further increase the highly dynamic nature of such networks
and adaptation becomes a powerful technique for protocol design. Under these modelling assumptions, we design, implement and evaluate a
new power conservation scheme for efficient data propagation. Our scheme is adaptive: it locally monitors the network conditions (density, energy) and accordingly adjusts the sleep-awake schedules of the nodes
towards improved operation choices. The scheme is simple, distributed and does not require exchange of control messages between
nodes.
Implementing our protocol in software we combine it with two well-known data propagation protocols and evaluate the achieved
performance through a detailed simulation study using our extended version of the network simulator ns-2. We focus on highly dynamic scenarios with respect to network density, traffic conditions and sensor node resources. We propose
a new general and parameterized metric capturing the trade-offs between delivery rate, energy efficiency and latency. The
simulation findings demonstrate significant gains (such as more than doubling the success rate of the well-known
propagation protocol) and good trade-offs achieved. Furthermore, the redeployment of additional sensors during network evolution
and/or the heterogeneous deployment of sensors, drastically improve (when compared to “equal total power” simultaneous deployment
of identical sensors at the start) the protocol performance (i.e. the success rate increases up to four times while reducing energy dissipation and, interestingly, keeping latency low).
This work has been partially supported by the IST Programme of the European Union under contract number IST-2005-15964 (
), the Programme
under the European Social Fund (ESF) and Operational Program for Educational and Vocational Training II (EPEAEK II) and the
Programme
of GSRT under contract number 03ED568. A preliminary version of this work has appeared in
[13]. 相似文献