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951.
952.
Labels in spreadsheets can be exploited for finding formula errors in two principally different ways. First, the spatial relationships between labels and other cells express simple constraints on the cells usage in formulas. Second, labels can be interpreted as units of measurements to provide semantic information about the data being combined in formulas, which results in different kinds of constraints.In this paper we demonstrate how both approaches can be combined into an integrated analysis, which is able to find significantly more errors in spreadsheets than each of the individual approaches. In particular, the integrated system is able to detect errors that cannot be found by either of the individual approaches alone, which shows that the integrated system provides an added value beyond the mere combination of its parts. We also compare the effectiveness of this combined approach with several other conceivable combinations of the involved components and identify a system that seems most effective to find spreadsheet formula errors based on label and unit-of-measurement information.  相似文献   
953.
The perception of duration is crucial when we make choices between immediate and delayed rewards. Immediate rewards are valued more than the same rewards if they are delayed. Preferences for earlier rewards become even stronger when the reward can be received within a subjectively proximate time frame. A “rational” decision to wait for a delayed reward may be overruled by an “impulsive” choice when the option for the closer reward falls within this proximate time range. Based on findings on circadian and circannual physiological rhythms, we suggest that there are 2 time units that are both biologically and culturally determined and have an impact on human experience and behavior: the day and the year. We highlight results of a neuroimaging study showing that rewards with delays up to 1 year are discounted differently than reward delays longer than 1 year. This duration-dependent discounting is associated with specific brain activation in the striatum. We present various conceptualizations of subjective time incorporated in parametric models of intertemporal decisions that may lead to a better understanding of human choice behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
954.
With the growth of competition between nations in our knowledge-based world economy, excellence programs are becoming a national agenda item in developing as well as developed Asian countries. The main purpose of this paper is to compare the goals, funding policies and selection criteria of excellence programs in China, Japan, Korea and Taiwan and to analyze the academic achievement of their top ranked universities in three areas: research output, internationalization, and excellence, by using data from the Shanghai Jiao Tong, QS, and HEEACT rankings. The effectiveness of Taiwan??s ??Development Plan for World Class Universities and Research Centers of Excellence?? was assessed as a case study in the paper via a survey targeting on 138 top administrators from 11 Taiwan??s universities and 30 reviewers. The study found that more funding nations had, the more outputs and outcomes they would gain, for example China. The Taiwan case demonstrates that world-class universities and research centers are needed in Asian nations despite the concerns for inequality which they raise.  相似文献   
955.
By triangulating analyses of content and reception with a focus on production, this article attempts to understand the dynamics of and underlying reasons for the media stigmatisation of place. The research described contributes to a body of work examining how mass media and other social forces factor in the creation of negative stereotypes that damage the reputations of the places in which the poor reside. The overarching framework of understanding, provided by Goffman’s theory of stigma, is complemented by two further inter-related theoretical approaches, namely Social Exclusion and Political Economy. Combining analyses of media production (practices), media content (discourses) and audience reception (beliefs, attitudes), we analyse the representation of one of Ireland’s most deprived public housing estates in the print and broadcast media. Having established the stigmatising character and impact of national and local media content via this tripartite methodology, we focus on identifying and explaining the media practices that serve to (re)produce the estate’s ‘spoiled identity’. Our analysis of journalists’ explanations for these practices identifies the commercial realities, which progressively influence media production, as directly impacting media producers’ relationships with, and depictions of, poor places. We conclude by examining debates regarding the potential for rehabilitating a spoiled identity.  相似文献   
956.
We present a new epoxy-based negative-tone dry film photoresist (DFR) for fabricating multilayer microfluidic devices using a lamination process combined with a standard photolithography technology. As proof-of-concept, a complex 3D-hydrodynamic focusing device was produced via a six-layer lamination process of 33 µm-thick DFR layers. The bonding strength of the new DFR was tested on silicon, glass, and titanium substrates, respectively. A maximum bonding strength of 37 MPa was obtained for the dry film photoresist laminated on glass. No leakage was found, and burst tests proved excellent robustness and sealing reliability of the microchannels.  相似文献   
957.
Polyurethane–siloxane thermoset copolymers were obtained from Isophorone diisocyanate trimer, Polycaprolactone triol and 10% of hydroxy terminated Polydimethyl siloxane. The copolymers showed a phase separated structure that depended on the conversion of the reaction and casting temperature. The different samples obtained had water contact angles higher than 90°. Moreover the contact angle values presented a maximum at intermediate reaction conversion. Although FTIR measurements showed that siloxane concentration at the surface increased with reaction time, the maximum contact angle value was related to the higher roughness calculated from AFM images. DMTA results confirmed that the phase separation was higher at intermediate conversions.  相似文献   
958.
A method to print two materials of different functionality during the same printing step is presented. In printed electronics, devices are built layer by layer and conventionally only one type of material is deposited in one pass. Here, the challenges involving printing of two emissive materials to form polymer light‐emitting diodes (PLEDs) that emit light of different wavelengths without any significant changes in the device characteristics are described. The surface‐energy‐patterning technique is utilized to print materials in regions of interest. This technique proves beneficial in reducing the amount of ink used during blade coating and improving the reproducibility of printed films. A variety of colors (green, red, and near‐infrared) are demonstrated and characterized. This is the first known attempt to print multiple materials by blade coating. These devices are further used in conjunction with a commercially available photodiode to perform blood oxygenation measurements on the wrist, where common accessories are worn. Prior to actual application, the threshold conditions for each color are discussed, in order to acquire a stable and reproducible photoplethysmogram (PPG) signal. Finally, based on the conditions, PPG and oxygenation measurements are successfully performed on the wrist with green and red PLEDs.  相似文献   
959.
The wireless industry is currently undergoing a major transition from second generation (2G) to third generation (3G) wireless technologies. The paper attempts to assess wireless technology migration options using the real options approach (ROA) to support the wireless network operators’ strategic decisions: to migrate or not, if so, which migration path to take. The preliminary result shows that the evolution of wireless network technologies between generations is desirable, but not within generations. Finally, from a strategic perspective, we should consider the possible challenges that may hinder migration. By identifying these challenges, we can be more watchful of transition pitfalls and can choose a better alternative.  相似文献   
960.
The fire-safe design of concrete structures, which incorporate post-tensioned prestressing tendons, has recently been the subject of debate within the structural engineering community, particularly when unbonded post-tensioned (UPT) prestressing tendons are used. Despite several studies aimed at furthering our understanding of the response of UPT concrete structures in fire, many aspects of their response in real fires remain poorly understood. An exhaustive summary of available test data, which have been used over the past five decades to generate fire design guidance for UPT concrete structures is given. Case studies showing the response of real UPT structures in severe building fires are also discussed. In both cases, the intent is to highlight inadequacies in the current state of knowledge for UPT buildings in fire and to prioritize areas for future research.  相似文献   
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