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1.
Morten Hertzum Rolf Molich Niels Ebbe Jacobsen 《Behaviour & Information Technology》2014,33(2):144-162
Usability evaluation is essential to user-centred design; yet, evaluators who analyse the same usability test sessions have been found to identify substantially different sets of usability problems. We revisit this evaluator effect by having 19 experienced usability professionals analyse video-recorded test sessions with five users. Nine participants analysed moderated sessions; 10 participants analysed unmoderated sessions. For the moderated sessions, participants reported an average of 33% of the problems reported by all nine of these participants and 50% of the subset of problems reported as critical or serious by at least one participant. For the unmoderated sessions, the percentages were 32% and 40%. Thus, the evaluator effect was similar for moderated and unmoderated sessions, and it was substantial for the full set of problems and still present for the most severe problems. In addition, participants disagreed in their severity ratings. As much as 24% (moderated) and 30% (unmoderated) of the problems reported by multiple participants were rated as critical by one participant and minor by another. The majority of the participants perceived an evaluator effect when merging their individual findings into group evaluations. We discuss reasons for the evaluator effect and recommend ways of managing it. 相似文献
2.
Jesper Andersen Ebbe Elsborg Fritz Henglein Jakob Grue Simonsen Christian Stefansen 《International Journal on Software Tools for Technology Transfer (STTT)》2006,8(6):485-516
We present a declarative language for compositional specification of contracts governing the exchange of resources. It extends
Eber and Peyton Jones’s declarative language for specifying financial contracts (Jones et al. in The Fun of Programming. 2003)
to the exchange of money, goods and services amongst multiple parties and complements McCarthy’s Resources, Events and Agents
(REA) accounting model (McCarthy in Account Rev. LVII(3), 554–578, 1982) with a view- independent formal contract model that supports definition of user-defined contracts, automatic
monitoring under execution and user-definable analysis of their state before, during and after execution. We provide several
realistic examples of commercial contracts and their analyses. A variety of (real) contracts can be expressed in such a fashion
as to support their integration, management and analysis in an operational environment that registers events. The language
design is driven by both domain considerations and semantic language design methods: a contract denotes a set of traces of
events, each of which is an alternative way of concluding the contract successfully, which gives rise to a CSP-style (Brooker
et al. in J.ACM 31(3), 560–599, 1984; Hoare in Communicating Sequential Processes, 1985) denotational semantics. The denotational semantics
drives the development of a sound and complete small-step operational semantics, where a partially executed contract is represented
as a (full) contract that represents the remaining contractual commitments. This operational semantics is then systematically
refined in two stages to an instrumented operational semantics that reflects the bookkeeping practice of identifying the specific
contractual commitment a particular event matches at the time the event occurs, as opposed to delaying this matching until
the contract is concluded. 相似文献
3.
Frido E. Smulders Harry Boer Poul H.K. Hansen Ebbe Gubi Kees Dorst 《Creativity & Innovation Management》2002,11(1):62-73
This paper describes and illustrates different configurations of the interface between new product development and production processes, including both intra–firm and inter–firm interfaces. These configurations are partly based on a process view of product innovation and partly on a structural view of product innovation. In addition to this typology of interfaces some integration mechanisms are described. The typology will serve as a basis for further research aimed at identifying consistent configurations of the different types of integration mechanisms that are available for industry to increase the effectiveness and efficiency of product innovation processes. 相似文献
4.
Martin Jarenmark Håkan Carlsson Vladimir M. Trukhan Matti Haukka Sophie E. Canton Monica Walczak Wilfred Fullagar Villy Sundström Ebbe Nordlander 《Inorganic chemistry communications》2010,13(3):334-337
The heterodinuclear complexes [FeZn(L)(CH3CO2)2]+ (L = ICIMP or IPCPMP) are structural models for the dinuclear active sites of plant purple acid phosphatases. They can be systematically synthesized from mononuclear iron complexes and enhance the rate of transesterification of 2-hydroxypropyl p-nitrophenyl phosphate, an assay for the catalytic hydrolysis performed by purple acid phosphatases. 相似文献
5.
Realization of the cloud computing infrastructure requires access to data anywhere, anytime at any device at a sufficient
perceived quality of service. Many Western European countries, such as Denmark, have a high percentage of individuals (inhabitants
and companies) that has access to broadband internet via cable, satellite and mobile. This gives a unique position in roll-out
and deploying intelligent cloud based services that can be applied for a number of purposes, but where lack of sufficient
capacity/quality and IT readiness will be barriers in realization of the “Global Information Multimedia Communication Village
(GIMCV)”. Broadband is here defined as more than 2 Mbps. In this paper, the combination of e-commerce, cloud computing and
broadband infrastructure has our focus, and its unique possibilities for the overall IT society. However, it is also about
a significant number of Small and Medium sized Enterprises (SMEs) that today applies manual billing systems or Excel like
systems in combination with severe lacks of sufficient IT skills. This means that the most commonly used systems are the ones
requiring the most of our time. Therefore, the move for the SME towards e-commerce and electronic processes has a significant
economical potential for the SMEs. E-commerce and other internet based services will simplify their business, and hence allow
the SMEs to focus on their core business which was their raison d’être. In addition to this can be added other fundamental
IT systems that will help their business, but that is outside the scope of this paper. Furthermore, this paper focuses on
infrastructural barriers and cloud computing; not only focusing on bandwidth, but also the entire issue of service offering.
Services offered via cloud computing solutions will minimize the SMEs investment in own hardware (HW), software (SW) and maintenance.
The focus is also the upgrade to a superior infrastructure that provides the platform for efficient cloud computing, for e-commerce,
and beyond. 相似文献
6.
Ebbe Toftgaard Poulsen Agnete Larsen Alen Zollo Arne L. J?rgensen Kristian W. Sanggaard Jan J. Enghild Carmela Matrone 《International journal of molecular sciences》2015,16(12):29446-29453
The Amyloid Precursor Protein (APP) has been extensively studied for its role as the precursor of the β-amyloid protein (Aβ) in Alzheimer’s disease (AD). However, our understanding of the normal function of APP is still patchy. Emerging evidence indicates that a dysfunction in APP trafficking and degradation can be responsible for neuronal deficits and progressive degeneration in humans. We recently reported that the Y682 mutation in the 682YENPTY687 domain of APP affects its binding to specific adaptor proteins and leads to its anomalous trafficking, to defects in the autophagy machinery and to neuronal degeneration. In order to identify adaptors that influence APP function, we performed pull-down experiments followed by quantitative mass spectrometry (MS) on hippocampal tissue extracts of three month-old mice incubated with either the 682YENPTY687 peptide, its mutated form, 682GENPTY687 or its phosphorylated form, 682pYENPTY687. Our experiments resulted in the identification of two proteins involved in APP internalization and trafficking: Clathrin heavy chain (hc) and its Adaptor Protein 2 (AP-2). Overall our results consolidate and refine the importance of Y682 in APP normal functions from an animal model of premature aging and dementia. Additionally, they open the perspective to consider Clathrin hc and AP-2 as potential targets for the design and development of new therapeutic strategies. 相似文献
7.
We addressed the question of whether felony case dispositions are associated with eyewitness identification evidence. Toward this end, 725 felony cases (rape, robbery, and assault) were randomly sampled from the archives of a District Attorney's Office in a large south-western city in the United States. A positive identification was present more often in accepted compared to rejected cases, although the association was significant in acquaintance cases (i.e., cases in which one or more of the eyewitnesses was familiar with the defendant), not stranger cases. Additionally, suspect and crime incident factors were associated with case issuing outcomes to a larger extent than eyewitness identification evidence. Analyses further indicated that eyewitness identification evidence was stronger in prosecuted compared to rejected cases in which eyewitness testimony was the sole evidence against the defendant. Neither the presence of multiple identifications nor nonidentifications of the suspect varied across issuing outcomes. The findings are discussed in relation to additional research that is needed at the police and prosecution stages to advance public policy development with respect to the evaluation of eyewitness identification evidence by prosecutors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
8.
基于SQL Server 2000的数据挖掘实现 总被引:1,自引:0,他引:1
大型数据库中的可升级数据挖掘是当今数据库研究领域的难题之一。SQL Server 是当今最流行的数据库管理软件之一,所以很容易想到在SQL Server 2000上研究在数据挖掘实现方面的主要方法。讨论了通过使用像SQL Server Analysis Service这样的典型工具来如何实现数据挖掘,且为商业组织的决定挖掘出必要的数据。 相似文献
9.
Igarashi B Christensen T Larsen EH Olsen NB Pedersen IH Rasmussen T Dyre JC 《The Review of scientific instruments》2008,79(4):045106
An electronics system has been assembled to measure frequency-dependent response functions of glass-forming liquids in the extremely viscous state approaching the glass transition. We determine response functions such as dielectric permittivity and shear and bulk moduli by measuring electrical impedances of liquid-filled transducers, and this technique requires frequency generators capable of producing signals that are reproducible over the span of several days or even several weeks. To this end, we have constructed a frequency generator that produces low-frequency (1 mHz-100 Hz) sinusoidal signals with voltages that are reproducible within 10 ppm. Two factors that partly account for this precision are that signals originate from voltages stored in a look-up table and that only coil-less filters are used in this unit, which significantly reduces fluctuations of output caused by changes of temperatures of circuits. This generator also includes a special triggering facility that makes it possible to measure up to 512 voltages per cycle that are spaced apart at uniform phase intervals. Fourier transformations of such data yield precise determinations of complex amplitudes of voltages and currents applied to a transducer, which ultimately allows us to determine electrical impedances of transducers with a reproducibility error that is only a few parts per hundred thousand. This equipment is used in tandem with a commercial LCR meter and/or impedance analyzer that give(s) impedance measurements at higher frequencies, up to 1 MHz. The experimental setup allows measurements of the transducer impedance over nine decades of frequency within a single run. 相似文献
10.
Chapell Mark S.; Blanding Z. Benjamin; Silverstein Michael E.; Takahashi Masami; Newman Brian; Gubi Aaron; McCann Nicole 《Canadian Metallurgical Quarterly》2005,97(2):268
This study investigated the relationship between test anxiety and academic performance in 4,000 undergraduate and 1,414 graduate students and found a significant but small inverse relationship between test anxiety and grade point average (GPA) in both groups. Low-test-anxious undergraduates averaged a B+, whereas high-test-anxious students averaged a B. Low-test-anxious female graduate students had significantly higher GPAs than high-test-anxious female graduate students, but there were no significant GPA differences between low- and high-test-anxious male graduate students. Female undergraduates had significantly higher test anxiety and higher GPAs than male undergraduates, and female graduate students had significantly higher test anxiety and higher GPAs than male graduate students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献