International temporary mobility of researchers: a cross-discipline study

The increasing literature addressing international mobility of researchers has repeatedly pointed out the lack of empirical data compiled over the last two decades, jeopardizing progress in the understanding of the characteristics and impacts of such human flows. This paper makes a contribution to the field by exploring the extent to which information obtained from researchers’ electronic curriculum vitae (CV) may be used to study temporary geographical mobility. We exploit a new type of data set—a comprehensive database of electronic CVs—developing a broad set of cross-discipline mobility indicators to assess the dimensions and characteristics of international research visits among a population of over 10,000 researchers. The sample population is made up of PhD holders working in the regional research system of Andalusia, Spain. Information regarding their international research visits over the last four decades is downloaded from CVs contained in the electronic scientific information system of the region. We assess mobility rates and the characteristics of the temporary mobile population. The analysis of visiting patterns shows significant differences in mobility profiles in terms of frequency, duration and destination of visits, across disciplines, career stages and time periods. The study also shows how different definitions of international mobility lead to substantial variations in cross-discipline mobility rates.     

A computer analysis of orientation devices for vibratory bowl feeders

Currently, vibratory bowl feeders are widely used in industry to feed small parts in assembly processes. The actual orientation of parts is achieved by various devices used in these feeders. However, each type of device performs only a limited function. The objective of this project was to develop a systematic approach which both analyses the geometrical and topological properties of parts designed in a CAD system and selects appropriate orientation devices to feed the designed parts.     

International publication patterns in social sciences: A quantitative analysis of theIBSS file

A scientometric analysis of social science literature is tried by using the machine-readable files of theIBSS 1981–1985. This is a comprehensive international bibliography in social sciences including cultural anthropology, economics, political science and sociology. Data used were 40,313 monograph records in theIBSS files. First, the number of scholarly monographs was examined by country. As a result, it is shown that a large number of monographs was published by only a very small number of countries. Second, the number of monographs was examined by language. A similar pattern as that of countries was observed. Third, the relationship between the publishing country and the language used is discussed. It is clarified that some languages, such as English, French and Spanish, are used in many countries because of their historical background such as colonization. Finally, we examined the correlation among the number of published monographs, GDP, population and the number of people attaining a university education. A regression model that incorporates GDP as explanatory variables explains well the variation of the number of monographs by countries (R²=0.77).     

Pattern recognition,image processing and computer vision in fifth generation computer systems

It is well-known that one of the goals of research for the last two decades or so in pattern recognition and its sub-areas, such as processing, analysis and understanding of image, speech and natural language, and computer vision techniques etc., has always been to develop fundamental techniques for flexible interactive intelligent man-machine interfaces for computers. In this paper, the author tries to argue that for the evolution of fifth generation computer systems (FGCS) as defined by Japanese scientists, some of the things required are realisation and implementation of the advances in pattern recognition and its sub-areas, not only to achieve the man-machine interface with a natural mode of communication, but also for the realisation of the basic mechanisms of inference, association and learning, which are inherent both in pattern recognition and in the core functions of FGCS. The next generation computers will be knowledge-based systems, which form a subdomain of artificial intelligence (a1) techniques, and soa1 provides the essential link between pattern recognition domains and different application systems. No attempt is made to discuss other essential conceptual building blocks, such as software engineering, computer architecture and very large scale integration technology unless these become very relevant in the discussions of concerned topics of the paper. A section on limitations of perception, learning and knowledge for computing machines is also included. This work was funded by the Knowledge-based Computer Systems Project of the Department of Electronics, Government of India.     

International cooperation of polish researchers with partners from abroad: A scientometric study

Publications resulting from international cooperation and included in seven SCI annual files 1987–1989 and 1992–1995 were analyzed. It was observed that after the political changes of the turn of 1980s considerable increase in the number of publications was accompanied by the geographic development of co-authorship. Information coming from SCI 1992–1995, elaborated, completed and encoded were entered into an own database designed for analytical purposes. During these four years above 9600 papers were published in over 1600 prestige journals, of which almost 2200 publications resulted from multilateral cooperation. Altogether the foreign coauthors came from 102 countries, but over 80% of international papers were published in cooperation with the partners from 11 countries. The domestic participants came from over 200 research and educational organizations. It was found that the biggest share of papers within this multidisciplinary file represented physics (≈40%), chemistry (≈21%), and biomedical research (≈11%).     

A comparative study of research performance in computer science

The paper compares the research performance in computer science of four major Western countries, India and China, based on the data abstracted from INSPEC database during the period 1993–2002. A total of 9,632 computer science papers recorded in INSPEC database were used for the comparison. The findings indicate that, on the one hand, the number of papers produced in China has considerably increased in the past few years. Particularly, in recent years, China occupies a remarkable high position in terms of counts of papers indexed by the INSPEC database. On the other hand, Chinese scientists preferred to publish in domestic journals and proceedings and shares of SCI-papers to the total journal papers for China have still remained the lowest. This indicates that the research activities of Chinese scientists in computer science are still rather “local” and suffer from a low international visibility. Various scientometric indicators, such as Normalized Impact Factor, ratio of papers in high quality journals are further adopted to analyze research performance and diverse finding are obtained. Nevertheless, for these surrogate indicators, China has optimistically achieved great progress, characterized with “low level of beginning and high speed of developing”. The policy implication of the findings lies in that China, as well as other less developed countries in science, can earn relative competitive advantages in some new emerging or younger disciplines such as computer science by properly using catch-up strategy. This revised version was published online in June 2006 with corrections to the Cover Date.     

The impact of conference ranking systems in computer science: a comparative regression analysis

Nowadays, conference publications have gained importance both quantitatively and qualitatively. People are seeking ways to distinguish the quality and impact of different conferences. Some bibliometrics like conference impact factor have been proposed to assess them. Meanwhile, associations in some countries have implemented several projects to build conference ranking systems that classify conferences based on certain quality measures. The Computing Research and Education Association of Australasia and China Computer Federation lists are two such well-known and widely used conference rating systems. They can serve as a guide when researchers need to publish their work. At the same time, they can influence researchers’ publication decisions. In this paper, we try to find out how publication patterns in different countries have been influenced by these two lists as well as by some other factors. A random-effect Negative Binominal Regression Model is used to identify the level of the impact caused by different factors.     

DNA甲基化定量测量国际比对CCQM P94.2

建立基因组DNA基质中CDKN2A基因甲基化含量的液相色谱同位素稀释质谱法和Sanger序列测定法两种定量方法,应用于国际物质量咨询委员会(consultative committee for amount of substance,CCQM)开展的DNA甲基化定量测量国际比对(CCQM P94.2)研究。考察DNA甲基化效率、酶解条件、色谱分离条件等对测定结果的影响,评定测量结果的不确定度。液相色谱同位素稀释质谱定量两个比对未知样的结果分别为未知样1:64.5%±6.1%;未知样2:46.7%±8.0%。Sanger序列测定法测定两个比对未知样的结果分别为未知样1:48.9%±1.0%;未知样2:48.9%±1.1%。与主导实验室标准值未知样1:51%±5.9%,未知样2:46.9%±4.9%十分符合,为我国DNA甲基化定量测量标准物质的研制奠定坚实的基础。     

Chinese researchers returning home: Impacts of international mobility on research collaboration and scientific productivity

The aim of this study is to contribute to the debate on the relationship between scientific mobility and international collaboration. This case study deals with leading Chinese researchers in the field of plant molecular life sciences who returned to their home country. A correlation analysis of their mobility history, publication output, and international co-publication data, shows the relationship between scientific output, levels of international collaboration and various individual characteristics of returned researchers. The outcome of the analysis suggests that while host countries may loose human capital when Chinese scientists return home, the so-called “return brain drain”, they may also gain in terms of scientific linkages within this rapidly emerging and globalizing research field.     

Surface transverse waves: properties, devices, and analysis

Surface transverse waves represent a new generation of the surface acoustic wave (SAW) family that offers advantageous properties without further demand for new materials or improved design and technology. The most effective activity in the surface transverse wave (STW) area has been realized during the last decade with high-performance devices achieved and analytical methods developed. The present paper reviews the basic achievements in historical and factual order. A state-of-the-art introduction is combined with discussion on the development tendencies with specific emphasis on sensor technology.     

A quantitative and automatic echographic method for real-time localization of endovascular devices

Current imaging methods for catheter position monitoring during minimally invasive surgery do not provide an effective support to surgeons, often resulting in the choice of more invasive procedures. This study was conducted to demonstrate the feasibility of non-ionizing monitoring of endovascular devices through embedded quantitative ultrasound (QUS) methods, providing catheter self-localization with respect to selected anatomical structures. QUS-based algorithms for real-time automatic tracking of device position were developed and validated on in vitro and ex vivo phantoms. A trans-esophageal ultrasound probe was adapted to simulate an endovascular device equipped with an intravascular ultrasound probe. B-mode images were acquired and processed in real time by means of a new algorithm for accurate measurement of device position. After off-line verification, automatic position calculation was found to be correct in 96% and 94% of computed frames in the in vitro and ex vivo phantoms, respectively. The average errors of distance measurements (bias ± 2SD) in a 41-step 10-cm-long parabolic pathway were 0.76 ± 3.75 mm or 0.52 ± 3.20 mm, depending on algorithm implementations. Our results showed the effectiveness of QUS-based tracking algorithms for real-time automatic calculation and display of endovascular system position. The method, validated for the case of an endoclamp balloon catheter, can be easily extended to most endovascular surgical systems.     

Band-like transport, high electron mobility and high photoconductivity in all-inorganic nanocrystal arrays

Flexible, thin-film electronic and optoelectronic devices typically involve a trade-off between performance and fabrication cost. For example, solution-based deposition allows semiconductors to be patterned onto large-area substrates to make solar cells and displays, but the electron mobility in solution-deposited semiconductor layers is much lower than in semiconductors grown at high temperatures from the gas phase. Here, we report band-like electron transport in arrays of colloidal cadmium selenide nanocrystals capped with the molecular metal chalcogenide complex In(2)Se(4)(2-), and measure electron mobilities as high as 16 cm(2) V(-1) s(-1), which is about an order of magnitude higher than in the best solution-processed organic and nanocrystal devices so far. We also use CdSe/CdS core-shell nanoparticles with In(2)Se(4)(2-) ligands to build photodetectors with normalized detectivity D* > 1 × 10(13) Jones (I Jones = 1 cm Hz(1/2) W(-1)), which is a record for II-VI nanocrystals. Our approach does not require high processing temperatures, and can be extended to different nanocrystals and inorganic surface ligands.     

A study on green organic light-emitting diodes with high electron mobility in hole block and electron transport layers

The electron mobility and hole blocking ability of BPhen, BCP, and ET137 were investigated by fabricating an electron only device and hole only device, respectively. Although it was observed that ET137 has the highest electron mobility, the device with ET137 as electron transporting layer was unable to obtain high efficiency alone and it was necessary to use a hole blocking layer because of the poor hole blocking ability due to the high-lying HOMO energy level. We fabricated green-emitting phosphorescent devices with various hole blocking layers and electron transporting layers. It was demonstrated that the high electron mobility of the electron transporting layer and hole blocking layer leads to high efficiency in organic light-emitting diodes. The device with BPhen and ET137 as hole blocking layer and electron transporting layer, respectively, showed the best efficiency properties. The maximum values of luminous efficiency, power efficiency, and quantum efficiency were 41.1 cd/A, 26.9 Im/W and 12.4%, respectively.     

Theory and practice of ubiquitous quantitative chemical analysis using conventional computer optical disk drives

We demonstrate a new attractive approach for ubiquitous quantitative chemical or biological sensing when analog signals are acquired from conventional optical disk drives, and these signals are used for quantitative detection of optical changes of sensing films deposited on conventional CD and DVD optical disks. Our developed analytical model of the operation of this Lab-on-DVD system describes the optical response of sensing films deposited onto the read surface of optical disks by taking into account the practical aspects of system performance that include possible reagent leaching effects, water sampling (delivering) efficiency, and possible changes of the film morphology after water removal. By applying a screen-printing process, we demonstrated a laboratory-scale automated production of sensing films with an average thickness of approximately 10 microm and a thickness relative standard deviation of <3% across multiple films. Finally, we developed a system for delivery of water-sample volumes to sensing films on the disk that utilized a multifunctional jewel case assembly.     

Rapid separation and quantitative analysis of peptides using a new nanoelectrospray- differential mobility spectrometer-mass spectrometer system

Differential mobility spectrometry (DMS) (see Buryakov, I. A.; Krylov, E. V.; Nazarov, E. G.; Rasulev, U. Kh. Int. J. Mass Spectrom. Ion Processes 1993, 128, 143-148), also commonly referred to as high-field asymmetric waveform ion mobility spectrometry (FAIMS) (see Purves, R. W.; Guevremont, R.; Day, S.; Pipich, C. W.; Matyjaszcyk, M. S. Rev. Sci. Instrum. 1998, 69, 4094-4105), is a rapidly advancing technology for gas-phase ion separation. The interfacing of DMS with mass spectrometry (MS) offers potential advantages over the use of mass spectrometry alone. Such advantages include improvements to mass spectral signal-to-noise, orthogonal/complementary ion separation to mass spectrometry, enhanced ion and complexation structural analysis, and the potential for rapid analyte quantitation. In this report, we investigate the use of our nanoESI-DMS-MS system to demonstrate differential mobility separation of peptides. The formation of higher order peptide aggregate ions (ion complexes) via electrospray ionization and the negative impact this has on DMS peptide separation are examined. The successful use of differential mobility drift gas modifiers (dopants) to reduce aggregate ion size and improve DMS peptide ion separation is presented. Following optimization of DMS peptide separation conditions, we examined next the feasibility of a new analytical platform which uses direct sample infusion with nanoESI-DMS-MS for ultrarapid analyte quantitation. Quantitation of a selected peptide from a semicomplex peptide mixture is presented. Initial feasibility results with this new approach demonstrate good accuracy and reproducibility, as well as an absolute mass sensitivity of 6.8 amol and a minimum dynamic range of 2500 for the peptide of interest. This report offers a first look at utilizing nanoESI-DMS-MS to create an ultrarapid (under 5 s) quantitative analysis platform and its potential in the high-throughput arena. Each ion separation technique, DMS and MS, offers orthogonal ion separation to one another, enhancing the overall specificity for this quantitative approach.     

Some aspects of citation indexes in Spain: A comparative analysis

This paper studies the main characteristics of the citation indexes currently developed in Spain. The paper compares the impact factors offered by Spanish citation indexes with the impact factor of Spanish journals also collected by the JCRs of the ISI (SCI and SSCI) over a five-year period (2001–2005). Spanish journals published in English have higher impact factor scores in the JCR databases of the ISI than in Spanish citation indexes.     

A bibliometric analysis of publications in computer networking research

Scientometrics - Computer networking is a major research discipline in computer science, electrical engineering, and computer engineering. The field has been actively growing, in terms of both...     

NPUA: A new approach for the analysis of computer experiments

An important problem in the analysis of computer experiments is the specification of the uncertainty of the prediction according to a meta-model. The Bayesian approach, developed for the uncertainty analysis of deterministic computer models, expresses uncertainty by the use of a Gaussian process. There are several versions of the Bayesian approach, which are different in many regards but all of them lead to time consuming computations for large data sets.In the present paper we introduce a new approach in which the distribution of uncertainty is obtained in a general nonparametric form. The proposed approach is called non-parametric uncertainty analysis (NPUA), which is computationally simple since it combines generic sampling and regression techniques. We compare NPUA with the Bayesian and Kriging approaches and show the advantages of NPUA for finding points for the next runs by reanalyzing the ASET model.     

Review and analysis of publications on scientific mobility: assessment of influence,motivation, and trends

Scientometrics - The phenomenon of scientific mobility, actively developing in recent decades, attracts increasing attention of researchers in view of its importance for the development of science,...