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Substantial efforts have been made to improve R&D project termination decisions. One major stream of research has demonstrated that discriminant functions can distinguish between successful and unsuccessful projects. It is of considerable importance to test the validity of discriminant functions. In the present study the authors show the applicability of a discriminant function that was originally developed by Balachandra for US R&D projects to data from British and German R&D projects. The results are mixed. It is encouraging that a very high percentage of projects can be correctly classified as successes or failures. But the discriminant functions vary between countries. Thus, the results reveal different management perceptions of project success factors in these countries 相似文献
3.
Anders Bruun Dimitrios Raptis Jesper Kjeldskov Mikael B. Skov 《Behaviour & Information Technology》2016,35(3):233-249
Coolness has recently started to be explored as a design goal for interactive products from practitioners as well as researchers within human–computer interaction (HCI), but there is still a need to further operationalise the concept and explore how we can measure it. Our contribution in this paper is the COOL questionnaire. We based the creation of the questionnaire on literature suggesting that perceived coolness is decomposed to outer cool (the style of a product) and inner cool (the personality characteristics assigned to it). In this paper, we focused on inner cool, and we identified 11 inner cool characteristics. These were used to create an initial pool of question items and 2236 participants were asked to assess 16 mobile devices. By performing exploratory and confirmatory factor analyses, we identified three factors that can measure the perceived inner coolness of interactive products: desirability, rebelliousness and usability. These factors and their underlying 16 question items comprise the COOL questionnaire. The whole process of creating the questionnaire is presented in detail in this paper and we conclude by discussing our work against related work on coolness and HCI. 相似文献
4.
Affective and analytical same-different discrimination tests for assessing the ability of consumers to discriminate between milks with subtle differences were designed by applying familiarization procedures to induce an affective/synthetic and analytical/synthetic perceptual strategy. The tests were then administered to 100 milk consumers and compared. In both same-different discriminations, consumers adopted a cognitive decision rule that used a β-strategy rather than a τ-strategy. Discrimination tests employing an affective/synthetic perceptual approach (which is the normal consumer perceptual process) resulted in higher discriminability than tests that employed an analytical/synthetic approach. Inter-individual differences in the consumer criteria (boundaries) used for same-different ratings were studied by examining the response distributions over the given response categories for the same pairs. According to the similarity of such response distributions, two different consumer segments were classified and their group discriminabilities differed significantly, with only the more sensitive group showing interactions between the affective/hedonic state and perceptual discriminability. 相似文献
5.
Wind resource assessment from C-band SAR 总被引:1,自引:0,他引:1
Merete Bruun Christiansen Wolfgang Koch Charlotte Bay Hasager 《Remote sensing of environment》2006,105(1):68-81
Using accurate inputs of wind speed is crucial in wind resource assessment, as predicted power is proportional to the wind speed cubed. First, wind speeds retrieved from a series of 91 ERS-2 SAR and Envisat ASAR images, at moderate wind speeds (2-15 m s− 1), were validated against in situ measurements from an offshore mast in the North Sea. The wind direction input, necessary for SAR wind speed retrievals, was obtained from the meteorological mast and from a local gradient analysis of wind streaks in the SAR images. A wind speed standard deviation of ∼ 1.1 m s− 1 was found when in situ wind directions were used. The use of local gradient wind directions yielded a standard deviation of ∼ 1.3 m s− 1. Wind speeds retrieved from three geophysical model functions (CMOD-IFR2, CMOD4, and CMOD5) were compared. The best approximation to the in situ measurements of wind speed was found for CMOD-IFR2, despite a bias on the order of − 0.3 m s− 1. CMOD4 retrievals also underestimated the wind speed, whereas the bias on CMOD5 retrievals was negligible. Then, wind resource assessments were made from the SAR-based wind observations to show how errors in wind speed from the different SAR wind retrievals were reflected in the wind statistics. The mean wind speed, obtained for all of the 91 SAR scenes, was linked closely to the bias of SAR wind retrievals. Agreement to ± 15% of the in situ measurements was found for all the wind retrieval methods tested. The accuracy of power density estimates for the entire data set was evaluated by the standard deviation of SAR wind retrievals relative to the in situ measurements. SAR wind fields retrieved with CMOD-IFR2, using in situ wind direction inputs, exactly yielded the power density predicted from in situ measurements alone. The SAR-based wind resource assessment also corresponded well to predictions from longer time series of in situ measurements. This indicates that a reliable wind resource assessment may be achieved from a series of randomly selected SAR images. The findings presented here could be useful in future wind resource assessment based on SAR images. 相似文献
6.
Casper Bruun Jensen 《Computer Supported Cooperative Work (CSCW)》2006,15(5-6):419-441
This paper discusses a research project in which social scientists were involved both as analysts and supporters during a
pilot with a new wireless nursing call system. The case thus exemplifies an attempt to participate in developing dependable
health care systems and offers insight into the challenges of developing and supporting such systems. The analysis proposes
that while dependability is not simply a technical issue, neither is it something, which can be improved merely by adding
a social dimension. Instead, it argues that dependability is a relative concept, which may mean different things conditional
on how it is specified in practice and who gets to do this. This relativity makes it important to relate the question of how
to support dependable health care systems to an analysis of both the politics of technology within specific projects and to
the politics of discourse, through which the researcher becomes involved in such projects. 相似文献
7.
Gunnar Gudnason Erik Bruun Morten Haugland 《Analog Integrated Circuits and Signal Processing》2000,22(1):81-89
This paper describes a chip for a multichannel neural stimulator for functional electrical stimulation (FES). The purpose of FES is to restore muscular control in disabled patients. The chip performs all the signal processing required in an implanted neural stimulator. The power and digital data transmission to the stimulator passes through a 5 MHz inductive link. From the signals transmitted to the stimulator, the chip is able to generate charge-balanced current pulses with a controllable length up to 256 s and an amplitude up to 2 mA, for stimulation of nerve fibers. The quiescent current consumption of the chip is approx. 650 A at supply voltages of 6–12 V, and its size is 3.9×3.5 mm2. It has 4 output channels for use in a multipolar cuff electrode. 相似文献
8.
Myocardial dynamic effects and pharmacokinetics of amlodipine were studied in the isolated retrogradely perfused and spontaneously beating guinea-pig heart. Pharmacokinetic analysis of drug accumulation showed one-compartment characteristics with an half-life of 76 min. Whereas disposition exhibited two-compartment characteristics with phasic half-lives of 25 and 174 min., respectively. Myocardial drug accumulation was increased by 600 times at steady-state compared to the perfusion liquid. Dynamic effect parameters were studied during increasing amlodipine concentrations from 0.16 to 220 nM. Dynamic steady-states developed within 20 min. Coronary flow-rate increased with an Emax of 119% and an EC50 of 1.2 x 10(-8) M. Amlodipine produced inhibitory effects on contraction amplitude and velocities of contraction and relaxation. Observed Emax-values and curve-fitted EC50-values were: 97, 97 and 94% and 1.10(-8), 7.7 x 10(-9) and 2.1 x 10(-8) M, respectively. Heart frequency was not changed. Oxygen consumption increased markedly to a maximum of 44% at 3 x 10(-8) M amlodipine and then decreased to nearly initial values. The frequency-corrected QT-interval decreased to a maximal extent of 20% at the three highest concentrations. Myocardial efficiency expressed as the ratio of contraction velocity times frequency to oxygen consumption exhibited a progressive decline to about 2% of initial values. The PQ-interval was not changed and the QRS-interval showed only a small but significant decrease at the highest amlodipine concentration. No arrythmogenic effects were observed. The study demonstrated a very slow accumulation and disposition of amlodipine in the guinea-pig heart with a steady-state myocardial drug concentrating accumulation of 600 times. Marked increase in coronary flow-rate and oxygen consumption accompanied by a progressive negative inotropic effect were observed. 相似文献
9.
JA Hejna PL Johnstone SL Kohler DA Bruun CA Reifsteck SB Olson RE Moses 《Canadian Metallurgical Quarterly》1998,26(4):1124-1125
Bacterial Artificial Chromosomes (BACs) have been used to complement a metabolic defect and to transfer a drug resistance marker into mammalian cells by electroporation. The selectable markers are stable and the recipient cells have BAC DNA integrated into the chromosomes as shown by fluorescent in situ hybridization, PCR and Southern hybridization. 相似文献
10.
A GaAs field-effect-transistor structure has been used as a detector for acoustic surface waves in the frequency range 65?200 MHz. The conversion loss is shown to be strongly dependent on the source-gate and source-drain voltages. The minimum value obtained is 26 dB for frequencies between 80 and 150 MHz. 相似文献