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1.
We have designed, developed, and tested a very promising thermal image analysis method for polygraph testing. The method achieved a correct classification rate of CCR= 84% on the test population to our avail. This method, once refined, can serve as an additional channel for increasing the reliability and accuracy of traditional polygraph examination. We extract subtle facial temperature fluctuation patterns through nonlinear heat transfer modeling. The modeling transforms raw thermal data to blood flow rate information. Then, we use the slope of the average periorbital blood flow rate as the feature of a binary classification scheme. The results come to support our previous laboratory findings about the importance of periorbital blood flow in anxious states. 相似文献
2.
A total of 126 patients (63 female, 63 male) underwent microsurgical removal of their cerebral arteriovenous malformations (AVMs) by the same surgeon. The mean age at surgery was 34.7 (6-72) years. The symptoms were intracerebral hemorrhage (37.3%), seizure disorder (34.9%) or focal neurological deficits and minor symptoms. According to the Spetzler/Martin scale, 20.6% of the AVMs were grade I, 28.6% grade II, 32.5% grade III, 14.3% grade IV and 4% grade V. In all, 78 AVMs (61.9%) were located in functionally important brain regions. The series was split into three different groups: small AVMs under 3 cm in diameter (n = 62/49.2%), medium-sized AVMs (n = 58/46%) and large AVMs (n = 6/4.8%). Seventeen patients had preoperative embolization of their AVM. All patients had postoperative angiographic control and 3- and 6-month follow-up. One patient died (0.8%), and another one (0.8%), in whom the AVM was incompletely resected, suffered a secondary hemorrhage. Seventeen (27.4%) of the patients with small AVMs developed transient neurological worsening post-operatively, which remained permanently significant in 3.2%. The respective numbers for the patients with medium-sized AVMs were 48.3% and 10.3% and for the large AVMs 83.3% and 33.3%. The results of microsurgical removal of cerebral AVMs can still be considered superior to the results of stereotactic radiosurgical treatment available from the literature-even for small AVMs. This is due to immediate exclusion of the AVM under direct local control of the angioarchitecture and thereby a reduced risk of secondary hemorrhaging and a decreasing morbidity rate with increasing time after the operation. Radiosurgical treatment requires a 2-year latency period for obliteration and carries a mortality rate of up to 12.5% and a rate of unexpected side effects of up to 20%. This treatment should be reserved for small, deep, surgically inaccessible AVMs or used as part of a multimodality treatment regimen consisting of partial embolization, partial excision and consecutive radiation of the residual nidus in initially very large AVMs. Embolization therapy-such as radiosurgery-carries a significant risk of morbidity (8%) and a mortality rate of up to 6%. It should only be considered for AVMs that are expected to be fully obliterated afterwards, or for primary inoperable AVMs that are to be changed into operable ones by embolization. Size reduction of otherwise operable AVMs does not justify the additional risk of embolization. Close collaboration of the specialties involved is desirable. 相似文献
3.
Function plotting using conic splines 总被引:1,自引:0,他引:1
4.
Ng G.I. Pavlidis D. Tutt M. Oh J.-E. Bhattacharya P.K. 《Electron Device Letters, IEEE》1989,10(3):114-116
The DC and microwave properties of strained In0.65Ga 0.35As/In052Al0.48As HEMTs (high electron-mobility transistors) with double-heterojunction design are presented. The high sheet carrier density and good carrier confinement give rise to excellent device performance with very low output conductance. For 1×150-μm2 long-gate HEMTs, the measured cutoff frequency f T and maximum frequency of oscillation f max are as high as 37 and 66 GHz, respectively 相似文献
5.
On the recognition of printed characters of any font and size 总被引:2,自引:0,他引:2
Kahan S Pavlidis T Baird HS 《IEEE transactions on pattern analysis and machine intelligence》1987,(2):274-288
We describe the current state of a system that recognizes printed text of various fonts and sizes for the Roman alphabet. The system combines several techniques in order to improve the overall recognition rate. Thinning and shape extraction are performed directly on a graph of the run-length encoding of a binary image. The resulting strokes and other shapes are mapped, using a shape-clustering approach, into binary features which are then fed into a statistical Bayesian classifier. Large-scale trials have shown better than 97 percent top choice correct performance on mixtures of six dissimilar fonts, and over 99 percent on most single fonts, over a range of point sizes. Certain remaining confusion classes are disambiguated through contour analysis, and characters suspected of being merged are broken and reclassified. Finally, layout and linguistic context are applied. The results are illustrated by sample pages. 相似文献
6.
Dr. Qingyun Tang Assist. Prof. Dr. Ioannis V. Pavlidis Dr. Christoffel P. S. Badenhorst Prof. Dr. Uwe T. Bornscheuer 《Chembiochem : a European journal of chemical biology》2021,22(16):2584-2590
Halide methyltransferases (HMTs) enable the enzymatic synthesis of S-adenosyl-l -methionine (SAM) from S-adenosyl-l -homocysteine (SAH) and methyl iodide. Characterisation of a range of naturally occurring HMTs and subsequent protein engineering led to HMT variants capable of synthesising ethyl, propyl, and allyl analogues of SAM. Notably, HMTs do not depend on chemical synthesis of methionine analogues, as required by methionine adenosyltransferases (MATs). However, at the moment MATs have a much broader substrate scope than the HMTs. Herein we provide an overview of the discovery and engineering of promiscuous HMTs and how these strategies will pave the way towards a toolbox of HMT variants for versatile chemo- and regioselective biocatalytic alkylations. 相似文献
7.
Bjorklund CM Pavlidis T 《IEEE transactions on pattern analysis and machine intelligence》1981,(2):144-155
The k-syntactic similarity approach is couched in graphical representation terms and its ability to provide global recognition capability while retaining a low time complexity is explored. One potential application domain, that of composite shape decomposition into approximately convex subshapes, is described. This is shown to be equivalent to finding cycles within a particular graph. The approach yields valid decompositions in many cases of interest, and is capable of identifying those cases where additional semantic considerations are necessary for proper analysis. The permissible graph structures representing composite shapes given a reasonable set of relations are determined. Experimental results on nonideal data are given. 相似文献
8.
A hybrid optoelectronic measurement system is constructed and used to obtain the large-signal characteristics of AlGaAs/GaAs heterojunction bipolar transistors. The measurement system utilizes a terahertz-bandwidth electrooptic transducer gated by 100-fs laser pulses to interrogate the time-domain waveforms at the device input and output nodes. A microwave signal phase-locked to the laser pulse-train is used to synchronously excite the device in both small-signal and large-signal regimes. The measurement system is capable of 50-GHz bandwidth and provides time-domain voltage waveforms that can be used directly to verify the time-domain results of the large-signal analysis 相似文献
9.
A method for large-signal transistor analysis is presented. The method is based on the harmonic-balance approach but makes use of input data from measured S-parameters instead of DC or pulsed DC characteristics and a large-signal equivalent circuit with harmonic elements. The topology of this circuit is nearly identical to commonly used small-signal equivalent circuits; its application allows a detailed interpretation of the computed results, which are very precise due to the use of small-signal S-parameters. The large-signal model is applied to HEMTs and MESFETs. Their saturation mechanisms are investigated and the operational difference is discussed. The importance of including higher harmonic signal components in the large-signal analysis is also shown 相似文献
10.
MA Dimopoulos M Papadopoulou E Andreopoulou C Papadimitriou N Pavlidis G Aravantinos A Aspropotamitis A Anagnostopoulos G Fountzilas S Michalas D Pectacides 《Canadian Metallurgical Quarterly》1998,70(1):70-74
The effect of pretreatment of human polymorphonuclear leukocites (PMNs), for 30 min with fluconazole (0.1, 1, 5 and 50 microgram/ml) and itraconazole (0.05, 0.5 and 5 microgram/ml) on phagocytosis and generation of free radicals (superoxide anion and hydrogen peroxide) was studied in vitro. Phorbol miristate acetate (200 nM) was used as a stimulant. The mean amount of superoxide anion generated by 2.5 x 10(5) PMNs per hour was 4.39 +/- 1.13 nmol for fluconazole-treated PMNs and 4.56 +/- 1.2 nmol for itraconazole, and that of hydrogen peroxide was 11.19 +/- 2.18 and 11.28 +/- 3.61 nmol, respectively. The phagocytosis percentages were 83.8% for the control group and 88. 7% in antifungal agent- treated PMNs; the phagocytosis index was 3.0 yeasts per PMN for both groups. The differences between the control and treated PMNs were not statistically significant at any of the tested concentrations. 相似文献