To signal or not to signal: That should not be the question

The purpose of the present research was to examine rates of turn signal use, a positive and potentially valuable means by which drivers can communicate. A second purpose was to explore factors that might impact these rates, including the modeling influence of other drivers. A series of observations involving more than 5600 vehicles making turns were recorded at a variety of intersections in British Columbia, Canada. Though the occurrence of signal use varied widely, ranging from a low of 54% to a high of 95%, the overall rate was 76%. Drivers used turn signals significantly less often when making right as compared with left turns, when traffic volume was higher, and when a designated turning lane was provided. In addition, compared with drivers following another vehicle not using signals, those following a vehicle with turn signals on were significantly more likely to activate their turn signals, suggesting a possible modeling effect. Both internal and external influences on turn signal use by drivers were considered. External factors explored in this research included direction of turn, traffic volume, intersection configuration, and the example of other drivers. It was concluded that the practice of signaling turns merits more research attention, since consistent use of signals is a potential contributor to enhanced safety for all road users.     

美容院的可为与不可为

近日,桂林市174家生活美容院被限期整改。这是桂林市卫生监督所公布的3·15保障健康权益卫生监督执法周专项行动中的检测和查处结果。这些美容院出了什么问题?违规开展医疗美容宣传。这样大的一个数字后面反映的是,目前生活美容场所普遍存在着违法宣传诱导消费者接受医疗美容现象。美容院:违规开展医疗美容宣传很普遍据悉,桂林市卫生监督所为做好此次专项监督工作,事前认真梳理和排查了有关投诉,针对桂林的实际情况进行了前期抽样监测取证。3月8日     

Citations as a measure of technological impact: A review of forward citation-based measures

The number of forward citations a patent receives accumulates over time and appears to be correlated to the patent‘s (i.e. invention's) technological impact. A dominant theory suggests that highly cited patents contain an important technological advance. However, a variety of citation based measures have been proposed by different authors. This study, via a narrative literature review, identified nine forward citation-based measures that appear of particular relevance. We describe each measure and present them in a comparative format.The measures are divided into two broad categories: firstly the ones that are particularly relevant to the patent level (citation index, forward citation frequency, generality, influence), and secondly the ones that are relevant to the patent portfolio level (current impact index, herfindal-hirschman index, hindrance index, relative patent position, technology strength).We hope research scholars and industrial users find this review helpful for citation analysis and intellectual property analytics, especially when wanting to employ forward citation-based measures to assess technological impact.     

To beat or not to beat: the history and development of heartpacemakers

The use of electrically-generated impulses to stimulate the contraction of the chambers of the heart began over sixty years ago and implanted pacemakers, in which a pulse generator complete with its power source is is surgically placed inside the body, were first used in the late 1950s. Since that time pacing has become a therapy used worldwide with over 250,000 implants undertaken per year. This paper introduces the operation of the cardiac conducting system-the body natural pacemaker-and indicates some of the problems which can arise within it. It goes on to trace the evolution of pacing systems from their origins to the `physiological' devices used today and gives an indication of some current lines of research     

To cite or not to cite: author self-citations and the impact factor

Author self-citations are another factor that affects the impact factor of a journal. Typically these self-citations are just counted as such. But to be more meaningful I suggest that when examining the contribution of authors?? self-citations to impact factors one should first count the number of citations in the text rather than in the reference list, and then discriminate between different kinds of author self-citations??from those that are informative to those that are self-enhancing??if these data are to be more credible.     

High field RF superconductivity: To pulse or not to pulse?

Experimental data on the behavior of superconductors under the application of RF fields of amplitude comparable to their critical fields are sporadic and not always consistent. In many cases the field level at which breakdown in superconducting RF cavities should be expected has not been clearly established. Tests conducted with very short (sim1mus) RF pulses indicate that in this mode of operation fields close to the critical values can be consistently reached in superconducting cavities without breakdown. The advantages and disadvantages of the pulsed method are discussed compared to those of the more standard continuous wave (cw) systems.     

To be or not to be: predicting soluble SecAs as membrane proteins

SecA is an important component of protein translocation in bacteria, and exists in soluble and membrane-integrated forms. Most membrane prediction programs predict SecA as being a soluble protein, with the exception of TMpred and Top-Pred. However, the membrane associated predicted segments by TMpred and TopPred are inconsistent across bacterial species in spite of high sequence homology. In this paper we describe a new method for membrane protein prediction, PSSM_SVM, which provides consistent results for integral membrane domains of SecAs across bacterial species. This PSSM encoding scheme demonstrates the highest accuracy in terms of Q2 among the common prediction methods, and produces consistent results on blind test data. None of the previously described methods showed this kind of consistency when tested against the same blind test set. This scheme predicts traditional transmembrane segments and most of the soluble proteins accurately. The PSSM scheme applied to the membrane-associated protein SecA shows characteristic features. In the set of 223 known SecA sequences, the PSSM_SVM prediction scheme predicts eight to nine residue embedded membrane segments. This predicted region is part of a 12 residue helix from known X-ray crystal structures of SecAs. This information could be important for determining the structure of SecA proteins in the membrane which have different conformational properties from other transmembrane proteins, as well as other soluble proteins that may similarly integrate into lipid bi-layers.     

Comparison of a citation-based indicator and peer review for absolute and specific measures of research-group excellence

Many different measures are used to assess academic research excellence and these are subject to ongoing discussion and debate within the scientometric, university-management and policy-making communities internationally. One topic of continued importance is the extent to which citation-based indicators compare with peer-review-based evaluation. Here we analyse the correlations between values of a particular citation-based impact indicator and peer-review scores in several academic disciplines, from natural to social sciences and humanities. We perform the comparison for research groups rather than for individuals. We make comparisons on two levels. At an absolute level, we compare total impact and overall strength of the group as a whole. At a specific level, we compare academic impact and quality, normalised by the size of the group. We find very high correlations at the former level for some disciplines and poor correlations at the latter level for all disciplines. This means that, although the citation-based scores could help to describe research-group strength, in particular for the so-called hard sciences, they should not be used as a proxy for ranking or comparison of research groups. Moreover, the correlation between peer-evaluated and citation-based scores is weaker for soft sciences.     

To publish or not to publish? On the aggregation and drivers of research performance

This paper presents a methodology to aggregate multidimensional research output. Using a tailored version of the non-parametric Data Envelopment Analysis model, we account for the large heterogeneity in research output and the individual researcher preferences by endogenously weighting the various output dimensions. The approach offers three important advantages compared to the traditional approaches: (1) flexibility in the aggregation of different research outputs into an overall evaluation score; (2) a reduction of the impact of measurement errors and a-typical observations; and (3) a correction for the influences of a wide variety of factors outside the evaluated researcher's control. As a result, research evaluations are more effective representations of actual research performance. The methodology is illustrated on a data set of all faculty members at a large polytechnic university in Belgium. The sample includes questionnaire items on the motivation and perception of the researcher. This allows us to explore whether motivation and background characteristics (such as age, gender, retention, etc.,) of the researchers explain variations in measured research performance.     

Assessing the quality of scholarly journals in Linguistics:An alternative to citation-based journal impact factors

Methods were developed to allow quality assessment of academic research in linguistics in allsub-disciplines. Data were obtained from samples of respondents from Flanders, the Netherlands,as well as a world-wide sample, evaluated journals, publishers, and scholars. Journals andpublishers were ranked by several methods. First, we weighted the number of times journals orpublishers were ranked as 'outstanding', 'good', or 'occasionally/not at all good'. To reduce theinfluence of unduly positive or negative biases of respondents, the most extreme ratings weretrimmed. A second weight reflects the (international) visibility of journals and publishers. Here,journals or publishers nominated by respondents from various countries or samples received agreater weight than journals or publishers nominated by respondents from one country or onesample only. Thirdly, a combined index reflects both quality and international visibility. Its use isillustrated on the output of scholars in linguistics. Limitations and potentials for application ofbibliometric methods in output assessments are discussed.     

To shrink or not to shrink: Hotelling's T2 chart based on shrunken covariance estimates

Several authors have studied the effect of parameter estimation on the performance of Phase II control charts and shown that large in‐control reference samples are necessary for the Phase II control charts to perform as desired. For higher dimensional data, even larger reference samples are required to achieve stable estimation of the in‐control parameters. Shrinkage estimation has been widely studied as a method to achieve stable estimation of the covariance matrix for high‐dimensional data. We investigate the average run length (ARL) distribution of the Hotelling T² chart when using a shrunken covariance matrix. Specifically, we explore the following questions: (1) Does the use of a shrinkage estimator of the covariance matrix result in reduced variability in the ARL performance of the T² chart? (2) Does the use of a shrinkage estimator of the covariance matrix result in a reduced occurrence of “strictly multivariate” false alarms on the T²chart? (3) How does shrinkage of the covariance matrix affect the out‐of‐control performance of the T² chart? We use a simulation study to investigate the use of shrinkage estimation with the Hotelling T² chart in Phase II. Our results indicate that, while shrinkage estimation affects the ARL performance of the T² chart, the benefits are small and occur in fairly specific circumstances. The benefits of shrinking may not justify the use of more advanced techniques.     

To illuminate or not to illuminate: Roadway lighting as it affects traffic safety at intersections

A two-pronged effort to quantify the impact of lighting on traffic safety is presented. In the statistical approach, the effects of lighting on crash frequency for different intersection types in Minnesota were assessed using count regression models. The models included many geometric and traffic control variables to estimate the association between lighting and nighttime and daytime crashes and the resulting night-to-day crash ratios. Overall, the presence of roadway intersection lighting was found to be associated with an approximately 12% lower night-to-day crash ratio than unlighted intersections. In the parallel analytical approach, visual performance analyses based on roadway intersection lighting practices in Minnesota were made for the same intersection types investigated in the statistical approach. The results of both approaches were convergent, suggesting that visual performance improvements from roadway lighting could serve as input for predicting improvements in crash frequency. A provisional transfer function allows transportation engineers to evaluate alternative lighting systems in the design phase so selections based on expected benefits and costs can be made.     

Impact factors, scientometrics and the history of citation-based research

Few contemporary inventions have influenced academic publishing as much as journal impact factors. On the other hand, debates and discussion on the potential limitations of, and appropriate uses for, journal performance indicators are almost as long as the history of the measures themselves. Given that scientometrics is often undertaken using bibliometric techniques, the history of the former is inextricably linked to the latter. As with any controversy it is difficult to separate an invention from its history, and for these reasons, the current article provides an overview of some key historical events of relevance to the impact factor. When he first proposed the concept over half a century ago, Garfield did not realise that impact factors would one day become the subject of such widespread controversy. As the current Special Issue of Scientometrics suggests, this debate continues today.