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81.
82.
As the sensitivity of the new in vitro cancer detection techniques increases, a larger number of "false positive" results can be expected from control populations apparently free from malignant disease at the time of the test. An attempt is made to predict the number of unexplained positives, together with the expected age and sex distribution, using published cancer registration statistics. The predicted numbers are compared with the observed numbers of unexplained positives in two clinical trials of the MEM test.  相似文献   
83.
Witnessing in merging biological, social and algorithmic realities is crucial to trust, as modelled in the YUTPA framework. Being witness and bearing witness is fundamental to human interaction. System participation in human communities of practice challenges the notion of witnessing and therefore the ability to build trust. Nevertheless, through trial and error, people in a variety of practices have found ways to establish the presence and develop trust in merging realities. This paper presents the results of 20 in-depth interviews with professionals from a variety of disciplines and nations. The conclusion of cumulative analysis is that systems do not witness themselves, but their output deeply affects the mental maps that human beings make of each other, the world around them and their own self. Essential qualities human beings seek when being involved with other beings are defined by granularity and reciprocity in the design of time (duration of engagement, synchronizing performance, integrating rhythms and moments to signify), place (body sense, material interaction, emotional space and situated agency), relation (shared meaning, engagement, reputation and use) and action (tuning, reciprocity, negotiation and quality of deeds). By designing granular interaction in 4 dimensions, reciprocity in witnessing obtains significance and the basis for establishing trust in a variety of presences emerges while human agency acquires potential.  相似文献   
84.
This correspondence describes a microcomputer system, called ?BE (for microprocessor-based English), for processing natural languages. Its techniques and facilities, however, should be extendible to other languages. By using the microprocessor as special purpose hardware for several functions of a natural language processor (in particular, hashing and parsing), the system aids computational linguists by increasing the computational power available for natural language investigations. An overview of ?BE is given followed by a more detailed discussion of the hasher and parser. The paper concludes with specific applications of the microprocessor system to computational linguistics. ?BE is not based on a particular theory of language so that the system's user may define his own theory and investigate its consequences. ?BE contains facilities and capabilities to assist such investigations.  相似文献   
85.
A national survey was carried out in Great Britain in 1978/79 to determine the weight loss occurring in pig carcasses between slaughter and 24 hours post mortem. A total of 20,600 carcasses were measured over a 12-month period, the sample covering forty-eight slaughtering plants and the main market weights of pig. At 24 hours post mortem, the overall mean weight loss was estimated to be 2·27% of the hot weight. The figure differed little between market weights or between times of the year, but there were important differences between slaughtering plants.  相似文献   
86.
A simple iterative dual algorithm for maximum entropy image restoration is presented. The dual algorithm involves fewer parameters than conventional minimization in the image space. Mini-computer test results for Fourier synthesis with inadequate phantom data are given.  相似文献   
87.
MINET in K.C     
Byrd GD  Smith MK  McDonald N 《Library Journal》1979,104(17):2044-2047
  相似文献   
88.
We have developed and tested a portable device that analyzes the electroencephalogram (EEG) to determine if petit mal epilepsy waveforms are present. Clinicians should rimd it useful in diagnosing seizure activity of their patients. The micropower, battery-operated, portable device indicates a seizure has occurred if three criteria are satisfied: 1) frequencies of 2.5-7 Hz, 2) large amplitude waves, and 3) minimum number of waves per second. Levels and counts are adjustable, thus insuring high reliability against noise artifacts and permitting each subject to be individually fitted. The device has shown promise in giving the patient a possible mechanism of seizure control or suppression.  相似文献   
89.
The main features of a passive thin film display cell based on the electrochemically reversible formation of a tungsten bronze according to the reaction
(colourless) WO3 + xM+ + xe? ? MxWO3(blue)
where 0 < x < 1 are considered. Chemical analysis of an electrochemically coloured WO3 film has confirmed the presence of M. It is shown that a critical requirement of these cells is that Dτ(qCm/Q)2 ≈ 1, where the symbols are, in order, the M+ diffusion coefficient, the required device response time, the electronic charge, the maximum practical volume concentration of M in the WO3 film and lastly the area colouring charge. Typical energy requirements might be about 10 mJ cm?2 per complete cycle in a favourable case.Ionic injection overpotentials and ionic diffusion both appear to play a significant role in determining cell currents. Preliminary diffusion coefficient results for Li+ in r.f. sputtered WO3 films are reported, and their predicted dependence of film structure is discussed. The optical absorption of coloured WO3 films is presented, and it is interpreted as being predominantly due to free-electron intraband transitions.  相似文献   
90.
This paper describes a study on the solidification of the pseudo binary eutectic system, consisting of unfractionated linear polyethylene and the faceted growing diluent 1, 2, 4, 5-tetrachlorobenzene. Crystallization under eutectic conditions resulted in very fine-grained structures, which were found to depend on the growth rate. This rate of solidification was varied by pulling the polymer solutions through a fixed temperature gradient of 3° C mm–1 at different speeds ranging from 1 to 216 mm h–1. Fibrillar polymer crystals with lateral dimensions of about 0.5 m remained after removal of the solid diluent. At rates of solidification in the region of 2 to 20 mm h–1, the fibrils appeared to be aggregated in domains of well oriented structures, closely resembling the complex regular structures of the eutectic Sn-Bi system. At higher speeds the fibrillar crystals formed an irregular three-dimensional network. The polymeric structures grown from more dilute mixtures were characterized by rectangular holes originating from the growth of faceted primary diluent crystals. Despite the complexity of the crystallization of the highly entangled polymer solutions there appears to be quite some similarities between the eutectic polymeric system investigated and faceted/non-faceted atomic or small molecular eutectics.  相似文献   
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