Frequency-domain approach to robust PI control     

Wieslaw Krajewski  Stefano Miani  Umberto Viaro 《Journal of The Franklin Institute》2005,342(6):674-687

The paper considers the problem of designing PI controllers for industrial processes approximated by a first-order time-delayed model. The suggested frequency-domain approach is based on a normalized open-loop transfer function and makes use of the loci of constant stability margins and other performance indices in the parameter space. In this way, it is possible to evaluate the effects of uncertainties in the process parameters and, thus, control system robustness. Some examples show how the procedure operates.  相似文献   

An international comparison of sectoral knowledge bases: persistence and integration in the pharmaceutical industry   总被引：1，自引：0，他引：1  

Stefano Brusoni  AldoGeuna   《Research Policy》2003,32(10):1897-1912

This paper builds upon and extends existing studies of scientific and technological specialisation by proposing an analytical framework to compare sectoral knowledge bases across countries. It develops the concepts of knowledge persistence and knowledge integration as the relevant dimensions along which knowledge bases can be compared. Persistence is studied by analysing the evolution of specialisation over time. It hints at the cumulative, path dependent nature of learning processes. Integration is studied by analysing the evolution of specialisation across different typologies of research. It hints at the complex, non-linear interdependencies that link the scientific and technological domains. On the strength of an original database encompassing 630,000 peer-reviewed papers published between 1989 and 1996 in 11 chemistry and pharmacology-related fields across three types of research (i.e. basic, applied and development), it is argued that countries with high degrees of both persistence and integration (e.g. the US in pharmacology) are the most likely sources of useful research results for EU firms’ innovative efforts in the pharmaceutical sector. Also, some doubts are cast on the existence of a European paradox in pharmaceuticals.  相似文献   

Changes in University Governance in France and in Italy     

Boffo  Stefano  Dubois  Pierre  Moscati  Roberto 《Tertiary Education and Management》2008,14(1):13-26

Tertiary Education and Management - The transformation of higher education systems under the pressure of new needs required by the “society of knowledge” in France and Italy has had a...  相似文献   

NO在赤铁矿(0001)表面吸附的第一性原理计算（英文）     

吴翠霞  孙涛  FABRIS Stefano  杜林 《中国科学院大学学报》2022,39(2):193-200

氮氧化物NO_x（NO,NO₂）是对人类健康有严重危害的大气污染物。近年来研究表明赤铁矿（α-Fe₂O₃）可作为高效光催化剂去除大气中NO_x,但NO_x气体在赤铁矿表面的吸附特性还未明确,阻碍了对其催化机理的进一步认识。基于密度泛函理论,采用包括电子强关联效应的PBE+U以及色散力修正的方法,对NO气体分子在α-Fe₂O₃ （0001）晶面的吸附行为进行深入研究,发现基于PBE+U方法获得的吸附能（E_ad=-0.64eV）比PBE获得的E_ad（-1.31eV）低近50%。这是由于电子强关联项U的引入降低了表面铁原子d轨道对价带顶的贡献,抑制了其化学活性,而NO具有一个未成对的π^*轨道电子,使得其对吸附基体的电子结构格外敏感。与+U不同,色散力修正不会显著改变体系的电子结构,只是使E_ad略有增加（-0.18 eV）。采用统计力学的Langmuir公式计算NO在α-Fe₂O₃ （0001）表面的热力学平衡占据数,发现基于+U的吸附能得到的平衡占据数与实验观测更为一致。这些结果揭示了电子强关联效应在α-Fe₂O₃表面化学中的重要作用,并为进一步研究NO_x在α-Fe₂O₃表面的光催化反应机理奠定了基础。  相似文献   

The impact of virtual technologies on knowledge-based processes: An empirical study   总被引：1，自引：0，他引：1  

Antonino Vaccaro  Francisco Veloso  Stefano Brusoni   《Research Policy》2009,38(8):1278-1287

This study examines the organizational knowledge creation processes in two highly virtual teams involved in new product development projects in the automotive industry. Using Nonaka's model of knowledge creation, we explore how the virtualization of knowledge-based processes, i.e. the intensive exploitation of information and communication technologies (ICTs), has led to new forms of knowledge creation at both the individual and organizational levels. In contrast to previous studies that identify knowledge codification as the main contribution of ICTs, this study provides detailed micro-level evidence about the ability of virtual technologies to support the transfer and the creation of new knowledge – both explicit and tacit – and offers some implications for scholars and practitioners.  相似文献   

Touching epistemologies: meanings of average and variation in nursing practice     

Richard Noss  Stefano Pozzi  Celia Hoyles 《Educational Studies in Mathematics》1999,40(1):25-51

We present a study of the meanings of average and variation displayed by paediatric nurses. We trace how these meanings shape, and are shaped by, nurses' interpretations of trends in patient and population data. We suggest a theoretical framework for making sense of the data which compares and contrasts nurses' epistemology with that of official mathematics. Finally, we outline some provisional didactical implications.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   

Universities’ attractiveness to students: The Darwinism effect     

Mattia Cattaneo  Hugo Horta  Paolo Malighetti  Michele Meoli  Stefano Paleari 《Higher Education Quarterly》2019,73(1):85-99

Due to significant government cuts to Higher Education funding in Southern European systems, their already underfunded universities were forced to increasingly compete for students as sources of additional revenue. Concurrently, families and students that continued to afford participation in Higher Education became more selective when choosing a university, realising the riskier investment that Higher Education participation had become. Through a competing destinations model and relying on all Italian private and public universities, this study finds that the competition forces characterising universities’ attractiveness over the last decade have changed since the financial crisis of 2008. In a context of lower demand for Higher Education, the competition for students grew and universities in close proximity were better prepared to face the new challenges, leading to the growth of Higher Education clusters.  相似文献   

Teacher training by alternating classroom work and work analysis: from the perspective of a social conception of meaning and action     

Stefano Bertone  Sébastien Chaliès  Eric Flavier 《Teachers and Teaching》2013,19(6):653-667

This article explores teacher training by the alternation of classroom work and work analysis using an approach based on a social conception of meaning and action. The advantage of this approach is that it allows the development of professional activity in preservice teachers (PTs) to be assessed by tracking how the reflective tools acquired in training evolve in work and/or work analysis situations. The concepts of ‘meaning’ and ‘expectation’ are helpful in discussing the empirical data from a research program designed to evaluate the potential for PTs’ professional development offered by the alternating work/analysis programs of French University Institutes of Teacher Training. The main conclusions concern the need to organize PTs’ professional experiences within a training network so that PTs are not left on their own to face the diverse and complex situations of daily professional exercise. The effective procedures are those that allow PTs to construct concrete and circumstance‐based expectations that the professional rules they have learned are still operational. These expectations help PTs to efficiently calibrate and interpret the meaning of their work experience, while also allowing them to prepare to act differently.  相似文献   

Soccer,religion, authority: notes on the early evolution of association football in Italy     

Stefano Pivato 《国际体育史杂志》2013,30(3):426-428

  相似文献   

Unravelling the dynamics of knowledge creation in communities of practice though complexity theory lenses     

Stefano?BorzilloEmail author  Renata?Kaminska-Labbé 《知识管理研究与实践》2011,9(4):353-366

Drawing on a longitudinal case study of Alpha Chemicals, we use four complexity theory constructs – adaptive tension, enabling leadership, enhanced cooperation, and boundary spanning – to explain the continuous knowledge creation dynamics in Communities of practice (CoPs). Our findings show that the virtual cycle of knowledge creation results from CoPs oscillating between guided and self-directed modes. In a guided mode, adaptive tension and enabling leadership prevail, resulting in knowledge expansion. In a self-directed mode, enhancing cooperation and boundary spanning are the most significant, resulting in knowledge probing. This research uncovers the value of conceptualizing CoPs as complex adaptive systems with emergent and intentional processes coexisting to create a virtual knowledge creation cycle. Our findings complement the dominant theory on CoPs’ insights by moving beyond the control/autonomy debate and highlighting that knowledge creation dynamics results from a flexible combination and recombination of the different top-down and bottom-up forces.  相似文献