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1.
This paper proposes a model for the parametric representation of linguistic hedges in Zadeh’s fuzzy logic. In this model each linguistic truth-value, which is generated from a primary term of the linguistic truth variable, is identified by a real number r depending on the primary term. It is shown that the model yields a method of efficiently computing linguistic truth expressions accompanied with a rich algebraic structure of the linguistic truth domain, namely De Morgan algebra. Also, a fuzzy logic based on the parametric representation of linguistic truth-values is introduced.  相似文献   
2.
This paper newly designs the recursive least-squares (RLS) fixed-lag smoother and filter using the covariance information in linear continuous-time stochastic systems. It is assumed that the signal is observed with additive white observation noise and the signal is uncorrelated with the observation noise. The estimators require the covariance information of the signal and the variance of the observation noise. The auto-covariance function of the signal is expressed in the semi-degenerate kernel form.  相似文献   
3.
Effectiveness of taurine in protecting biomembrane against oxidant   总被引:3,自引:0,他引:3  
The effect of taurine in protecting biomembrane attacked by hypochlorous acid (HOCl) was examined using canine erythrocytes which had been pre-treated with HOCl. In the treatment, most of the HOCl was consumed as a result of its reaction with a number of electrophilic substances, such as free amino groups (-NH2) in the membrane, whereas hemoglobin inside the cells was not oxidized. The lysis of HOCl-treated erythrocytes was dependent on the concentration of HOCl and on the incubation time at 37 degrees C. Taurine inhibited the lysis at 37 degrees C in a dose dependent manner. During the incubation of HOCl-treated erythrocytes with taurine, an appreciable amount of monochlorotaurine (TauNHCl) was detected in the supernate. This suggests that taurine might remove the oxidized chlorine from HOCl-treated erythrocytes, resulting in the production of TauNHCl. The effect of taurine on the removal of Cl+ moiety was further examined using Sepharose gel with free amino groups. Taurine removed Cl+ moiety from HOCl-treated Sepharose gel, and the yield of TauNHCl depended on the concentration of taurine and the incubation time. These results indicate that taurine might inhibit the hemolysis by scavenging the oxidized chlorine moiety from the HOCl-treated erythrocytes. Inhibition of the HOCl-induced hemolysis was also observed with other amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
The resistance of a novel silica-based N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide (TODGA) polymeric adsorption material (TODGA/SiO2-P) against nitric acid, temperature and γ-irradiation had been investigated. The adsorption property of the treated TODGA/SiO2-P was evaluated by a 3 M HNO3 solution containing 0.01 M Nd(III). It was found that both 3 and 0.01 M HNO3 concentrations did not decrease the stability of TODGA/SiO2-P at 25°C. The quantity of TODGA leaked from TODGA/SiO2-P was equivalent to its solubility in the corresponding HNO3 aqueous solution. The effect of 3 M HNO3 on the leakage of TODGA at 80°C was significantly higher than that in 0.01 M HNO3 as well as in all cases at 25°C. The amount of Nd(III) adsorbed towards the treated TODGA/SiO2-P was determined in the range of 0.143–0.148 mmol/g for the HNO3 concentration effect and 0.142–0.0506 mmol/g for the temperature effect. γ-Irradiation showed a more noticeable destruction effect on TODGA/SiO2-P. The content of TODGA leaked increased with an increase in the γ-irradiation dose (ID) from 1.06 to 3.72 MGy in terms of the linear equation [TODGA]=794.5ID+84.0. The amount of Nd(III) adsorbed onto the irradiated TODGA/SiO2-P decreased rapidly from 0.134 to 0.0438 mmol/g, which was lower than 0.153 mmol/g, the adsorption of fresh TODGA/SiO2-P for Nd(III), according to the equation QNd(III)=−0.0301ID+0.160, showing that a large quantity of TODGA leaked from TODGA/SiO2-P. The adsorbed amount of Nd(III) decreased obviously in this order: the HNO3 concentration effect, temperature effect and γ-irradiation.  相似文献   
5.
In this paper, we propose a new design for the recursive least-squares (RLS) Wiener fixed-lag smoother and filter in linear discrete-time wide-sense stationary stochastic systems. It is assumed that the signal is observed with additive white observation noise. The signal is uncorrelated with the observation noise. The estimators require knowledge of the system matrix, the observation matrix and the variance of the state vector. These quantities can be obtained from the auto-covariance function of the signal. In the estimation algorithms, moreover, the variance of the observation noise is assumed to be known, as a priori information.  相似文献   
6.
This paper discusses the issue of how to use fuzzy targets in the target-based model for decision making under uncertainty. After introducing a target-based interpretation of the expected value on which it is shown that this model implicitly assumes a neutral behavior on attitude about the target, we examine the issue of using fuzzy targets considering different attitudes about the target selection of the decision maker. We also discuss the problem for situations on which the decision maker’s attitude about target may change according to different states of nature. Especially, it is shown that the target-based approach can provide an unified way for solving the problem of fuzzy decision making with uncertainty about the state of nature and imprecision about payoffs. Several numerical examples are given for illustration of the discussed issues.  相似文献   
7.
Combination of LiBH4 and LiNH2 by ball milling forms the series of novel complex hydrides Li2BNH6, Li3BN2H8 and Li4BN3H10, depending on the combination ratios. The crystal structure of Li4BN3H10 analyzed by synchrotron X-raydiffraction measurements is determined to be a cubic system (space group: I213) with the lattice constant of a=10.673(2)Å. It should be emphasized that Li4BN3H10 is an ionic crystal which is composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]-. These anions are located in the vertex and face-center of the cubic sub-lattice, and the lithium cation Li+ in the interstitial site between the anions, respectively. The other series of complex hydrides, Li2BNH6 and Li3BN2H8, are also predicted to possess similar structures composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]-.  相似文献   
8.
The Capitanian (Late Guadalupian) Maokou Formation at Chaotian in northern Sichuan, South China, is composed mainly of shallow marine shelf carbonates deposited on the Tethyan side of South China. By detailed field mapping and scientific drilling, we newly found out unique fossil assemblages and a sharp lithologic change in the upper part of the Maokou Formation. The main part of the Maokou Formation (over 130 m thick) is composed of algal packstone with Wordian-Capitanian large-tested fusulines, rugose corals and other sessile benthos, whereas the Uppermost Member (13 m thick) is composed of black limy mudstone/chert with Capitanian offshore biota (ammonoids, radiolarians, and conodonts). The topmost Capitanian conodont zones are missing; however, the Maokou Formation is disconformably overlain by 260+/-4 Ma volcanic ash (Wangpo bed) and the Early Lopingian Wujiaping Formation with plant-bearing coaly mudstone and shallow marine carbonates (packstone). The newly identified facies change indicates that northern Sichuan has experienced rapid sea-level changes in the late Guadalupian, i.e., first a transgression in the mid-Capitanian and then a regression across the Guadalupian-Lopingian boundary. As the end-Guadalupian is characterized by a global regression, such a volatile sea-level fluctuation, in particular the sea-level rise, is unique to the Tethyan side of South China. The newly recognized relatively deep-water late Guadalupian sequence adds new paleo-environmental information and further provides a paleotectonic interpretation of the low-latitude eastern Tethyan margin immediately before the end-Guadalupian mass extinction.  相似文献   
9.

Purpose

The purposes of this study were to evaluate the reproducibility for measuring the cold pressor test (CPT)-induced myocardial blood flow (MBF) alteration using phase-contrast (PC) cine MRI, and to determine if this approach could detect altered MBF response to CPT in smokers.

Materials and methods

After obtaining informed consent, ten healthy male non-smokers (mean age: 28 ± 5 years) and ten age-matched male smokers (smoking duration ≥ 5 years, mean age: 28 ± 3 years) were examined in this institutional review board approved study. Breath-hold PC cine MR images of the coronary sinus were obtained with a 3 T MR imager with 32 channel coils at rest and during a CPT performed after immersing one foot in ice water. MBF was calculated as coronary sinus flow divided by the left ventricular (LV) mass which was given as a total LV myocardial volume measured on cine MRI multiplied by the specific gravity (1.05 g/mL).

Results

In non-smokers, MBF was 0.86 ± 0.25 mL/min/g at rest, with a significant increase to 1.20 ± 0.36 mL/min/g seen during CPT (percentage change of MBF (?MBF (%)); 39.2% ± 14.4%, p < 0.001). Inter-study reproducibility for ?MBF (%) measurements by different MR technologist was good, as indicated by the intraclass correlation coefficient of 0.93 and reproducibility coefficient of 10.5%. There was no significant difference between smokers and non-smokers for resting MBF (0.85 ± 0.32 mL/min/g, p = 0.91). However, ?MBF (%) in smokers was significantly reduced (-4.0 ± 32.2% vs. 39.2 ± 14.4%, p = 0.011).

Conclusion

PC cine MRI can be used to reproducibly quantify MBF response to CPT and to detect impaired flow response in smokers. This MR approach may be useful for monitoring the sequential change of coronary blood flow in various potentially pathologic conditions and for investigating its relationship with cardiovascular risk.  相似文献   
10.
A low-speed screen/film system was used to investigate structure mottle, i.e., the density fluctuation of an x-ray film due to inhomogeneous screen structure. The tube voltage dependence of the Wiener spectra of the structure mottle was separately determined for front and back film emulsions. The Wiener spectral values of the structure mottle of the front emulsion were greater than those of the back emulsion at lower tube voltages. The spectral values of the structure mottle of the front emulsion decreased with tube voltage, while those of the back emulsion increased. We explain these phenomena by the behavior of the Wiener spectra of the relative spatial fluctuation of fluorescence intensity due to following reasons: (1) spatial thickness fluctuation of the screen produces a relative spatial fluctuation of x-ray energy absorbed in the screen, and (2) as the distance between the emulsion of the film and the average position of the x-ray absorption in the screen lengthens, the number of random scattering and absorption of light photons increase.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994.  相似文献   
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