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1.
The link between science and technology represents a major strategic stake, so the relation between scientific bibliographic
references and technical bibliographic references can be of very important documentary interest. To set up this link, International
Patent Classification catchwords have been used as a switching language. A previous feasibility study had shown the possibilities
of such a full automatic correspondence and its obvious inadequacies. We present here the most important modifications brought
to this correspondence, in particular the consideration of multilingual indexes which allow to link several indexation fields
with one of the most complete representation of patent classification. The major evolution of our project affects the correspondence
mechanism which now generates a global reindexation of bibliographic reference with classification codes. We also discuss
the concept of correspondence itself which must be interpreted as a simple presumption of the link. There are some consequences
due to these developments: first, insofar as there is not an univocal relation, end users do not have to select switching
keywords which generate concordances. They can directly use codes which symbolize the industrial property classification.
Next, main documentary indicators do not seem to be adapted to measure the performance evaluation of this new field. It has
the single role of suggesting trails that can be explored. Lastly, it seems that only end users should be able to supply a
complete validation and we show that a documentary validation is not sufficient. 相似文献
2.
Dynamic analogues of von Karman-Donnell type shell equations for doubly curved, thin isotropic shells in rectangular planform
are formulated and expressed in displacement components. These nonlinear partial differential equations of motion are linearized
by using a quadratic extrapolation technique. The spatial and temporal discretization of differential equations have been
carried out by finite-degree Chebyshev polynomials and implicit Houbolt timemarching techniques respectively. Multiple regression
based on the least square error norm is employed to eliminate the incompatability generated due to spatial discretization
(equations>unknowns). Spatial convergence study revealed that nine term expansion of each displacement inx andy respectively, is sufficient to yield fairly accurate results. Clamped and simply supported immovable doubly curved shallow
shells are analysed. Results have been compared with those obtained by other numerical methods. Considering uniformly distributed
normal loading, the results of static and dynamic analyses are presented.
A list of symbols is given at the end of the paper 相似文献
3.
This review article discusses PDMS (polydimethylsiloxane) microfluidic devices and their biological applications. First, the already developed devices are classified from the viewpoints of underlying technology within a common logical framework comprising single-layer, multilayer, and integrated devices, as well as surface chemistry modifications of PDMS. Combinatorial techniques are applied to re-derive existing devices within this framework. Next, the relevant scales of both microfluidics and biology are compared, obtaining the promise and limitations of PDMS microfluidics. Finally, the body of work is reclassified in terms of addressed biological applications and compared to the standard methods in cellular and molecular biology, to offer insights for future devices and applications. 相似文献
4.
Alberto Carpinteri Marco Paggi Nicola Pugno 《International Journal of Fracture》2006,141(3-4):535-547
The problem of brittle crack propagation and fatigue crack growth in functionally graded materials (FGMs) is addressed. The proposed analytical approach can be used to estimate the variation of the stress-intensity factor as a function of the crack length in FGMs. Furthermore, according to the Paris’ law, the fatigue life and the crack-tip velocity of crack propagation can be predicted in the case of fatigue crack growth. A comparison with numerical results obtained according to the Finite Element method will show the effectiveness of the proposed approach. Detailed examples are provided in the case of three-point bending beam problems with either a FGM interlayer, or a FGM external coating. A comparison is presented between two types of grading in the elastic modulus: a continuous linear variation in the FGM layer and a discrete approximation with a multi-layered beam and a constant Young’s modulus in each layer. 相似文献
5.
The US has emerged as the world leader in science and technology research and development in the 60 years following World War II. This status is due, in part, to a successful public–private partnership in research and higher education fostered after the war, and to the fiercely competitive and innovative nature of US industry. This paper provides some background to the complexities of US federal funding of research and development, as well as a brief history of US science and technology policy following World War II. The paper describes how research is managed and funded in the US; outlines how the US federal government interacts with universities and private industry; remarks on the nature of international cooperation; and comments on the future direction of US science and technology policy, including growing challenges to its position of leadership. 相似文献
6.
High volume, highly automated, information intensive, short cycle manufacturing systems severely tax most conventional statistical process control techniques. To meet this new manufacturing domain's control requirements, a new approach is needed. This paper presents such a process control procedure, sufficient statistics process control (SSPC). By drawing on empirical Bayes techniques, SSPC models the time sequence of the process while simultaneously reducing to a few sufficient statistics the large volume of incoming data. As a result, it provides real time, on-line quality control. The paper discusses the conceptual and mathematical foundations for SSPC. Its operation is illustrated through an example. Finally, the paper concludes with a discussion of the limitations of SSPC. 相似文献
7.
Forming teams: an analytical approach 总被引:10,自引:0,他引:10
The selection of multi-functional teams is a key issue in problem solving. Currently there are no papers in the literature that discuss analytical approaches to forming teams. Furthermore, no comprehensive model exists to prioritize team membership based on customer requirements or product characteristics. To deal with the underlying complexities of the team selection process, a methodology for team formation is developed. The methodology is based on the Analytical Hierarchy Process (AHP) approach and the Quality Function Deployment (QFD) method. A QFD planning matrix is used to organize the factors considered in the team selection. The importance measure for each team member is determined with the AHP approach. A mathematical programming model is developed to determine the composition of a team. The methodology developed in this paper is tested by the selection of teams in concurrent engineering. A detailed discussion of the model implementation and hov/ to reduce the number of comparisons in the AHP process is presented. Possible modifications of the model to include “soft factors”, i.e., leadership, morale, personalities of group members, group values and so on are also discussed. 相似文献
8.
Although the number of older adults with access to landline and mobile phones has grown in recent years, little research exists that investigates how older adults use and potentially combine the two technologies for communication with the members of their social support networks. Therefore, this study explored how the composition of older adults' social companionship networks is related to the frequency of landline and mobile phone communication with their network members. In addition, the study examined the association between landline and mobile phone communication as well as their relationship with in-person communication in such networks. The survey data were gathered using an ego-centered social support approach in a nationwide representative sample of retired older adults in Slovenia. The results of multiple regression analyses revealed that the composition of a social companionship network better predicts the frequency of landline rather than mobile phone communication of older adults with their network members. The non-significant relationship between the frequency of landline and mobile phone communication suggested that the two technologies very likely have a different role in the maintenance of social companionship networks. The study also found a difference between the importance of control variables related to the socio-demographic characteristics of older adults for the frequency of landline and mobile phone communication. While age, education, and living alone significantly predicted the frequency of mobile communication with older adults' network members, significant predictors of their landline communication included gender and health impairments. 相似文献
9.
Scientometrics - The purpose of the present paper is to investigate the formation mechanism of big data technology cooperation networks by considering the combined effect of three key factors,... 相似文献
10.
This paper examines the effect of different types of collaboration on the level of Postharvest Food Losses (PHFL) and the proportion of low-quality peaches produced using a unique data-set of Greek peach producers. Quantile regression techniques are adopted to estimate the effects at different points of the conditional distribution of our variables of interest. The findings of this study suggest that high levels of collaboration between producers and cooperatives are associated with both low levels of PHFL and a low proportion of low-quality peaches. We also find that specific types of collaboration, such as ‘goal congruence’, can play a significant role in reducing PHFL and improving the quality of peach production at the extremes of the distribution. Important policy implications regarding collaborative practices and systems that can be implemented to reduce PHFL and boost a producer’s performance together with sustainability credentials are drawn from this study. 相似文献
11.
The paper presents the large deformation flexural response of composite laminated skew plates subjected to uniform transverse pressure. Third order shear deformation theory (TSDT) and von-Karman’s nonlinearity is used for the analysis. Skew domain is mapped into a square domain and finite degree double Chebyshev series is used to discretize the space domain. No grid generation is required in the present solution technique. The nonlinear equations are linearized using quadratic extrapolation technique and the behavior of moderately thick laminated composite skew plates is studied. The effects of geometric nonlinearity, transverse shear, boundary conditions, aspect ratio and modular ratio on the behavior of laminated composite skew plates are discussed in detail. 相似文献
12.
Analytical science has gone through several turning points, one of the most decisive of which was signaled by the development and massive use of instruments for analytical purposes. One other pivotal turning point was the inception of computer science, which not only enabled the automatic control of analytical systems but also facilitated the acquisition of vast amounts of data and their processing with the aid of chemometrics. Following the growing significance of automation and miniaturization in recent times, the early 21st century is witnessing the rise of nanotechnology as a new, increasingly important, revolutionary trend in science in general and analytical science in particular. The ability to exploit molecular interactions between analytes and nanoparticles has opened up new, challenging prospects in this area. Good proof of the interest aroused by nanoparticles is the large number of papers on their use in quantum dots, fullerene, aurum nanoparticles, or carbon nanotubes published in recent years. 相似文献
13.
We argue in favour of artificial neural networks for exploratory data analysis, clustering andmapping. We propose the Kohonen self-organizing map (SOM) for clustering and mappingaccording to a multi-maps extension. It is consequently called Multi-SOM. Firstly the KohonenSOM algorithm is presented. Then the following improvements are detailed: the way of namingthe clusters, the map division into logical areas, and the map generalization mechanism. Themulti-map display founded on the inter-maps communication mechanism is exposed, and thenotion of the viewpoint is introduced. The interest of Multi-SOM is presented for visualization,exploration or browsing, and moreover for scientific and technical information analysis. A casestudy in patent analysis on transgenic plants illustrates the use of the Multi-SOM. We also showthat the inter-map communication mechanism provides support for watching the plants on whichpatented genetic technology works. It is the first map. The other four related maps provideinformation about the plant parts that are concerned, the target pathology, the transgenictechniques used for making these plants resistant, and finally the firms involved in geneticengineering and patenting. A method of analysis is also proposed in the use of this computerbasedmulti-maps environment. Finally, we discuss some critical remarks about the proposedapproach at its current state. And we conclude about the advantages that it provides for aknowledge-oriented watching analysis on science and technology. In relation with this remark weintroduce in conclusion the notion of knowledge indicators. 相似文献
14.
Citation networks in information science 总被引:3,自引:0,他引:3
Irina V. Marshakova 《Scientometrics》1981,3(1):13-25
The method of co-citation analysis is used to build citation networks in information science. As data base the first 13 volumes (1961–1973) of the leading Soviet journal in the field (Nauchno-tekhnicheskaya Informatsiya) were used. The results reveal the topical structure of information science, the communities of authors and the names of single leading scientists. The evaluation of scientists' work is based on two measures: productivity (with or without co-authorship) and popularity (popularity of authors and popularity of papers). 相似文献
15.
Electrochromism (EC) is a unique property of certain materials that undergo an electrochemical-induced change in colouration. During the last decades, electrochromic materials (ECMs) have been applied in a variety of technologies ranging from smart windows to information displays and energy storage devices. More recently, ECMs have attracted the attention of the (bio)sensing community thanks to their ability to combine the sensitivity of electrochemical methods with the intuitive readout of optical sensors. Although still a nascent technology, EC-based sensors are on the rise with several targets (e.g. cancer biomarkers, bacteria, metabolites and pesticides), which have already been detected by (bio)sensors using ECMs as transducers. In this review, we provide the reader with all the information to understand EC and its use in the development of EC-based biosensors. 相似文献
16.
F. Arsac D. Bianchi J.M. Chovelon P. Conchon C. Ferronato A. Lair M. Sleiman 《Materials science & engineering. C, Materials for biological applications》2008,28(5-6):722-725
This paper reports on the development of three specific methods allowing to better understand the mechanism of the photocatalytic degradation of organic pollutants both in air and in gas phases. The first method uses a home made IR cell to study the TiO2 surface during the photocatalytic degradation. The second method uses an ATD/GC/MS system to study the gas phase at a ppbv level during the degradation while the third one uses an HPLC/NMR system to discriminate between different positional isomers. 相似文献
17.
Igor Beli? 《Vacuum》2006,80(10):1107-1122
The paper is an attempt to describe how neural networks may be used as an approximation-modelling tool. A brief survey of the evolution of the approximation theory and neural networks is presented. Practical applications are based on modelling of vacuum science problems, especially the modelling of a cold cathode pressure gauge. The problem of approximation of wide range functions, that are one of the characteristics of vacuum science problems, is introduced. Parameters such as pressure or cathode current span over several decades and neural networks are not suitable for any approximation of such functions; therefore, two strategies need to be introduced, and these are described. The approximation made by the neural network is obtained by the training process. The models obtained by several independent repetitions of training processes performed on the same training set lead to slightly different results. Therefore the definition of training stability is introduced and described. Finally, some practical hints regarding the neural network synthesis (design) are given. 相似文献
18.
Dr. G. Marinoschi 《Acta Mechanica》1996,114(1-4):71-81
Summary In the first part of the paper the equations of a nonadiabatic motion produced by a perturbation in an electrically conducting radiative gas, moving in a magnetic field are given. In the second part an analytical approach of the solution is considered by the Fourier transform. The dispersion equation is found in some particular cases of propagation and a qualitative study of the time behaviour of the solution is given, too. 相似文献
19.
University professors face numerous challenges, especially when teaching issues related to political behavior. Recent studies in Brazil have shown that technology, clarity of information and impartial debates in the classroom have led to the development of more frequent political behaviors among Brazilian students. However, this research subject remains poorly addressed in Brazil. We investigated the development of political attitudes and political behavior of undergraduate students in Brasília, Brazil. We applied questionnaires to students (N = 349) in undergraduate courses (social, exact and health sciences) of a public university in Brasília (Federal District), capital of Brazil. Principal Components Analysis was used and three dimensions of political attitudes were created: (i) Degree of political knowledge Factor (PK), (ii) Positive Feelings about Politics Factor (PFP) and (ii) Negative Feelings about Politics Factor (NFP). The results suggest that students from social sciences undergraduate courses have a higher PK average in comparison to other student groups. Moreover, a linear regression model was developed for PFP factor. For PFP and NFP, the students from the social sciences areas were statistically significant (p < 0.05). Based on the outcomes of this study, we argue that it is essential for teachers to be aware of the importance of introducing themes related to political behavior in the classroom, considering the influence that political attitudes have on political behavior. It is the professor's role to stimulate impartial debate, free of personal preferences while presenting arguments from the students' arguments, in order to promote the scientific understanding of these subjects. 相似文献
20.