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91.
Fontoura Filho R.N. Schilling M.T. Mello J.C.O. Pereira J.L.R. 《Power Systems, IEEE Transactions on》1995,10(2):739-744
This paper describes a practical methodology to obtain adequacy equivalents which can be used in a large variety of power systems transmission analysis problems. The suggested technique is very simple and has characteristics of high flexibility and favourable accuracy. The procedure is thoroughly described and illustrated by an application to a small test system 相似文献
92.
R Erttmann T Tafese F Berthold R Kerbl J Mann L Parker F Schilling P Ambros H Christiansen M Favrot H Kabisch B Hero T Philip 《Canadian Metallurgical Quarterly》1998,34(9):1391-1397
Between January 1986 and May 1996, 870,313 children were tested in European neuroblastoma (NB) screening programmes. Among these children, 82 cases of NB (age range 4-24 months, median 11 months) were detected by screening. 83% of the patients had localised NB and 17% were diagnosed with generalised NB (stage 4, 10%; stage 4s, 7%). Unfavourable biological markers (MYCN amplification, loss of heterozygosity (LOH) 1p36, DNA di/tetraploidy) were observed in 14% of 76 biologically examined cases. The median follow-up time of all the patients was 21.5 months (range 1-101 months). To date, 69 patients are in complete remission (CR) and 2 patients have died due to therapy (stage 4, 1 patient; stage 3, 1 patient with unfavourable markers). Apart from screened patients, 16 other patients with NB were found who had previously had a normal screening test, i.e. 'false negative' patients (age range 10-41 months, median 31.5 months). The median interval between screening and diagnosis was 24.5 months (range 6-35 months). 11 of the 'false negative' patients suffered from generalised NB (stage 4) and 5 had localised NB at diagnosis. Unfavourable biological markers were observed in 7/12 patients. 5 patients have died, 2 achieved partial remission and 9 CR. 9 of the 11 patients with unfavourable biological markers diagnosed due to NB screening are currently in CR. It is very likely that, among the patients without unfavourable biological markers, we detected tumours which may have regressed spontaneously. These children may have undergone 'unnecessary,' but unavoidable, diagnostic procedures and therapy. To reduce the number of 'false negative' patients, a later screening could be helpful and should be evaluated. 相似文献
93.
The authors investigated implications of agonistic onset for anxiety and dispersive motivation in maturing wild house mouse males (Mus domesticus). Laboratory-kept fraternal pairs either developed agonistic dominance or stayed amicable during their first 2 months of life, when the authors assessed open-field behavior and dispersal propensity. State anxiety was lower in amicable than agonistic males and higher in subordinate than dominant ones. During subsequent dispersal trials, 1 dominant and 1 amicable male from 2 fraternal pairs were concomitantly introduced into seminatural enclosures containing 3 females. One male invariably became territorial. The defeated males, if previously dominant, dispersed at significantly higher rates than if previously amicable. The authors conclude that agonistic onset during development represents an adaptive behavioral switch from a submissive-philopatric to agonistic-dispersive coping strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Milstein L.B. Schilling D.L. Pickholtz R.L. Erceg V. Kullback M. Kanterakis E.G. Fishman D.S. Biederman W.H. Salerno D.C. 《Selected Areas in Communications, IEEE Journal on》1992,10(4):655-668
Because of the continually increasing demand for mobile communications, it has been suggested that personal communication networks (PCNs) be established in the 1850-1990 MHz range. However, that band of frequencies is currently occupied by various microwave signals transmitted by users ranging from utility companies to state and local agencies. In order to allow both sets of users to occupy these frequencies as well as improve the spectral efficiency of this band, a spread-spectrum overlay is proposed, whereby a code-division multiple-access (CDMA) PCN would share the spectral band with the existing narrowband microwave traffic. The results of several field tests which have been designed to demonstrate the feasibility of an overlay of this type are discussed 相似文献
95.
In the present study the distribution of tenascin in cholesteatoma was immunohistochemically investigated. The results were compared with those in external auditory meatal skin and in retroauricular skin of healthy controls. The staining pattern was additionally correlated to the degree of cell proliferation as detected by the monoclonal antibody MIB-1 (Ki-67 antigen). Retroauricular skin showed a limited distribution of tenascin in the papillary dermis and a sparse reactivity of MIB-1 in only a few epithelial cells. External auditory meatal skin revealed a more pronounced reaction for tenascin and MIB-1. In contrast, cholesteatoma tissue exhibited an abundant and continuous expression of tenascin covering the whole stroma compartment. This coincided with a significant increase of MIB-1-positive cells in the basal and suprabasal epithelial layers. Doublestaining experiments revealed most prominent stromal tenascin-expression in areas with marked signs for epithelial proliferation. This suggests that tenascin is selectively increased in response to epidermal hyperproliferation. This matrix protein thus shows a quantitatively and qualitatively enhanced expression under pathological conditions. Moreover, the abundant reactivity for tenascin in the cholesteatoma provides evidence of a deregulated cell-matrix interaction involved in the hyperproliferative process of cholesteatoma formation. 相似文献
96.
The operation of the projection code is introduced, and the error rate performance is determined. A new combinatorial generating function technique is used to compute the weight distribution of a cylindrical projection code, which is then employed to obtain upper and lower bounds of the bit error rate of the code. We then apply a state equation technique to compute the generating function of a convolutional projection code. This new generating function technique is needed since the standard state-diagram technique cannot realistically be used to obtain the generating function of a typical convolutional projection code which can have a constraint length of 56 相似文献
97.
Clinical vs quantitative evaluation of cutaneous sensation 总被引:1,自引:0,他引:1
PJ Dyck PC O''Brien W Bushek KF Oviatt K Schilling JC Stevens 《Canadian Metallurgical Quarterly》1976,33(9):651-655
A comparison of the evaluation of cutaneous sensation by neurologic examination and by quantitative assessment in 107 patients with various neuromuscular disease has shown that there is a reasonably good correlation between the recognition of abnormalities of cutaneous sensation by clinical and by quantitative methods. Clinical neurologists tend to underestimate abnormalities of touch-pressure sensation. The quantitative evaluation of cutaneous sensation is useful in quality control of the clinical examination, in correlating the nature of sensation loss with the compound action potential and morphometry of biopsied nerve, in providing a score of sensation to follow the course and the effect of treatment protocols, and in monitoring for an adverse effect on sensation by an environmental or industrial poison. There is a good correlation between abnormality of touch-pressure sensation and loss of large myelinated fibers of sural nerve in neuropathy. 相似文献
98.
The purpose of this paper is to show that signals which are adaptive delta modulation (ADM) encoded can be arithmetically processed directly, without first decoding or converting to pulse code modulation (PCM) format. By operating on the serial DM bit streams, the sum, difference and product can be obtained in PCM and ADM format. Employing a four-term, non-recursive, averaging filter after the processors, we show that, for constant inputs, the signal-to-noise ratio (SNR) of the DM devices is exactly the same as that of their PCM counterparts. Although we have used the Song audio mode ADM [1] in the realization of our arithmetic processors, the designs are general enough to be applied to a large class of digital ADMs. To keep all systems practically realizable, we only employ operations which can be constructed with standard digital hardware, that is, adder, delays, hard-wired scalars and common logic circuits. Consequently, all our ADM devices can be manufactured with large scale integration where the distinct advantage is low cost and high reliability. 相似文献
99.
K Sedlarik H Eger J Wilde F Vollmar G Reimann B Schilling G Seelig H Fiehring 《Canadian Metallurgical Quarterly》1976,9(5):302-315
Coronary thrombosis was induced in 14 miniature pigs by means of direct current. The induction electrode was introduced via the common carotid artery into the coronary artery. The intensity of current (1 mA) and the duration of current flow (60 min) were kept constant in all the experimental animals. 6 miniature pigs survived the period of observation (48 h). In all instances, an injury to the intima was the morphopathological location factor. With the exception of one animal, which died after an induction time of 60 min, coronary thrombosis was stated in all the miniature pigs. The experimental arrangement which produces closed-thorax coronary thrombosis is suited for cardiosurgical, physiopathological and pharmacological experiments, especially because the anatomy and the degree of development of the porcine heart are most similar to those of the human heart. 相似文献
100.
The mathematical foundation for a linear lumped transistor model is developed from the nonlinear regional model proposed by Schilling. A one-dimensional model is described with simple analytic equations representing carrier density and electric field profiles and stored charge across the base and collector regions of a bipolar transistor. The regional boundaries are derived as simple functions of the device parameters, e.g., impurity profile, and operating conditions at its terminals. A one-to-one correspondence between these physical device parameters and lumped model elements is provided by the model. The linear regional model is demonstrated to be equivalent to its nonlinear counterpart, consequently to Gummel's charge control model. 相似文献