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1.
The paper argues that an effective solution to information and knowledge management (KM) needs of practitioners in the construction industry can be found in the provision of an adapted knowledge environment that makes use of user profiling and document summarization techniques based on information retrieval sciences. The conceptualization of the domain through ontology takes a pivotal role in the proposed knowledge environment and provides a semantic referential to ensure relevance, accuracy, and completeness of information. A set of KM services articulated around the selected ontology have been developed, using the Web services model, tested, and validated in real organizational settings. This provided the basis for formulating recommendations and key success factors for any KM project development.  相似文献   
2.
Measures of interestingness play a crucial role in association rule mining. An important methodological problem, on which several papers appeared in the literature, is to provide a reasonable classification of the measures. In this paper, we explore Boolean factor analysis, which uses formal concepts corresponding to classes of measures as factors, for the purpose of clustering of the measures. Unlike the existing studies, our method reveals overlapping clusters of interestingness measures. We argue that the overlap between clusters is a desired feature of natural groupings of measures and that because formal concepts are used as factors in Boolean factor analysis, the resulting clusters have a clear meaning and are easy to interpret. We conduct three case studies on clustering of measures, provide interpretations of the resulting clusters and compare the results to those of the previous approaches reported in the literature.  相似文献   
3.
The present study investigated the fabrication and characterization of bio-based sustainable films composed of a terrestrial plant raw material, namely Opuntia ficus-indica (OFI) cladodes powder (CP) and a marine seaweed derivative, namely agar (A). The effect of glycerol concentration on the properties of the casted films was evaluated at four different contents, namely 30, 40, 50 and 60 wt%. The films present UV-blocking properties, as well as moderate mechanical performance, thermal stability, and water vapor transmission rate (WVTR). The results point to an increase in thickness, elongation at break, moisture content, water solubility, and WVTR with increasing glycerol content. On the contrary, Young's modulus, tensile strength, and water contact angle decreased as glycerol concentration increased. The best combination is obtained for the film with 30% glycerol, based on an intermediate compromise between physical, mechanical, thermal, and barrier properties. All these outcomes express the potentiality of the powder obtained from grinding the OFI cladodes as raw material to produce low-cost films for the development of sustainable packaging materials.  相似文献   
4.
Fe- and Mn-promoted sulfated zirconia was used to catalyze the conversion ofn-pentane in a flow reactor at temperatures in the range of –25 to 40C andn-pentane partial pressures in the range of 0.005 to 0.01 atm. The rates of reaction increased with time on stream during an induction period and then decreased rapidly. The predominant reaction at –25C and short times on stream was isomerization to give isopentane; no dibranched products were observed. The selectivity for isomerization decreased and that for disproportionation increased with increasing temperature, with disproportionation becoming predominant at 40C; the principal product was then isobutane. The product distribution data are consistent with acid-base catalysis and carbocation intermediates. However, there appears to be more to the reaction mechanism than acid-base chemistry, and the roles of the iron and manganese promoters are not yet explained.  相似文献   
5.
In this paper, we propose a new approach that guarantees the stability and robustness of an adaptive control law of a nonlinear system.The control diagram proposed contains a Takagi–Sugeno–Kang fuzzy controller (TSK-FC) and a training block allowing the online adaptation of the FC parameters. The adaptation algorithm used is based on the gradient with minimization of the quadratic error between the system output and that desired by using the direct method of Lyapunov. However, our approach considers the gradient step of each adaptive FC parameter to be bound. This approach was applied to the control of an inverted pendulum. The results obtained confirm well the validity of such an adaptation especially the guarantee of the pendulum stability and the robustness of its control with respect to the disturbances introduced on the FC parameters and the pendulum itself.  相似文献   
6.
7.
The biosorption characteristics of copper(II) ions using Posidonia oceanica biomass were investigated. Experimental parameters affecting the biosorption process such as pH level, contact time, biosorbent dosage and temperature were studied. The equilibrium data were applied to the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models. The Langmuir model fitted very well the equilibrium data, and the maximum uptake of Cu(II) by Posidonia oceanica was found to be 76.92 mg/g. The mean free energy E (10.78 kJ/mol) from the D-R isotherm indicated a chemical ion-exchange mechanism. Kinetic results showed that the pseudo-second-order kinetic model was well fitted to the experimental data. Thermodynamic parameters depicted the exothermic nature of biosorption and the process was feasible and spontaneous. The results of FTIR (Fourier-transform infrared spectroscopy) revealed that carboxyl, amine, and hydroxyl groups on the biomass surface were involved in the biosorption of Cu(II) ions.  相似文献   
8.
The International Journal of Advanced Manufacturing Technology - The paper discusses a generic procedure for the parameter design of product and process development using planned and non-planned...  相似文献   
9.
After looking for a convenient definition of accuracy for finite-volume schemes on structured meshes, a high-order accurate scheme is constructed for the Euler equations. Thanks to suitably weighted discretization operators, the proposed scheme is third-order on mildly deformed grids and second-order on highly deformed grids. The influence of mesh deformations on the scheme accuracy is studied theoretically and numerically. Numerical results are shown for a Lamb vortex, subsonic flow past a cylinder and transonic flow past a NACA0012 airfoil.  相似文献   
10.
The characterization of virgin olive oils from six Tunisian cultivars, namely Chétoui, Ain Jarboua, Jarboui, Regregui, Rekhami and Neb Jmel, grown in Nebeur (a region of the Kef) was carried out. These cultivars dominate their natural habitats, but with the exception of the Chétoui cultivar they are only scattered throughout the nation. Several analytical parameters were evaluated; these include quality index, fatty acid composition, chlorophylls, carotenoids, sterols, α‐tocopherol and phenolic compounds. Their relationship with oxidative stability was also tested. The main phenols found were tyrosol, hydroxytyrosol, the dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol, oleuropein aglycon and pinoresinol. These phenolic compounds, the colorimetric total phenol content and o‐diphenols showed significant correlations with oxidative stability. Furthermore, most of the analytical parameters of the oils that were determined in this study were greatly influenced by genetic factors (cultivar).  相似文献   
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