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排序方式: 共有1335条查询结果,搜索用时 15 毫秒
101.
Yuan Miao Zhi-Qiang Liu Chee Kheong Siew Chun Yan Miao 《Fuzzy Systems, IEEE Transactions on》2001,9(5):760-770
We present the dynamic cognitive network (DCN) which is an extension of the fuzzy cognitive map (FCM). Each concept in the DCNs can have its own value set, depending on how precisely it needs to be described in the network. This enables the DCN to describe the strength of causes and the degree of effects that are crucial to conducting meaningful inferences. The arcs in the DCN define dynamic, causal relationships between concepts. Structurally, DNCs are scalable and more flexible as compared to FCMs. A DCN can be as simple as a cognitive map and FCM, or as complex as a nonlinear dynamic system. To demonstrate the potential applications of DCNs, we present some simulation results. This paper represents our first attempt to develop a dynamic fuzzy inference system using causal relationships. There are many interesting and challenging theoretical and practical issues in DCNs open to further research 相似文献
102.
The effect of organic salt, tetrabutylammonium hexafluorophosphate (TBAPF6) doping on the performance of single layer bulk heterojunction organic solar cell with ITO/MEHPPV:PCBM/Al structure was investigated where indium tin oxide (ITO) was used as anode, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEHPPV) as donor, (6,6)-phenyl-C61 butyric acid methyl ester (PCBM) as acceptor and aluminium (Al) as cathode. In contrast to the undoped device, the electric field-treated device doped with TBAPF6 exhibited better solar cell performance under illumination with a halogen projector lamp at 100 mW/cm2. The short circuit current density and the open circuit voltage of the doped device increased from 0.54 μA/cm2 to 6.41 μA/cm2 and from 0.24 V to 0.50 V, respectively as compared to those of the undoped device. The significant improvement was attributed to the increase of built-in electric field caused by accumulation of ionic species at the active layer/electrode interfaces. 相似文献
103.
Md Zainul Abedin Alias A Karim Faiyaz Ahmed Aishah A Latiff Chee‐Yuen Gan Farid Che Ghazali Md Zaidul Islam Sarker 《Journal of the science of food and agriculture》2013,93(5):1083-1088
BACKGROUND: Sea cucumber (Stichopus vastus) is considered an underutilized resource, since only its stomach and intestines are eaten raw as salad in a few countries and the remaining parts, especially the integument rich in collagen, is discarded. Hence a valuable by‐product having potential nutraceutical and pharmaceutical applications is wasted. In the present investigation, pepsin‐solubilized collagen (PSC) from the integument of S. vastus was isolated, purified and characterized. RESULTS: Sodium dodecyl sulfate–polyacrylamide gel electrophoretic analysis showed that the purified collagen was of type I, consisting of three α1 chains of approximately 122 kDa each. The peptide map of PSC digested by V8 protease was different from that of calf skin type I collagen. Fourier transform infrared spectroscopy revealed that the triple helical structure was well preserved in isolated collagen. The denaturation temperature of PSC was 21.23 °C and showed good gel‐forming capability at pH 6.5 and 300 mmol L?1 NaCl. CONCLUSION: It is inferred that the collagen isolated from S. vastus integument has potential for use as an alternative to land‐based mammalian collagen in food, nutraceuticals and pharmaceutical industries. © 2012 Society of Chemical Industry 相似文献
104.
The study investigates the effect of inherent structural properties of liquid substrates on physical vapor-deposited metallic condensates. Due to the limitations in characterizing the atomic structure of different kinds of liquids, quantitative analysis of all the influencing parameters of the liquid substrate is difficult. Real time considered computing simulation is called for to realize the effects of such properties, which gives direct analyzable results. As representatives of physical and chemical properties of substrates, the molecular frequency and adsorption probability (~binding energy) are utilized as the key simulation parameters. Nucleation kinetics represented by conventional equations and an adapted time algorithm are employed to guarantee a correct, comparable and efficient simulation technique. The results show the substrates’ influence on the ‘morphology’ and ‘formation time’ of the film. In particular, the non-uniform morphology and low coverage observed under ‘liquid-substrate conditions’ are in agreement with experimental observations. The method can also be applied for predicting the condensate morphology for various vapor/substrate systems with known conditions. 相似文献
105.
Manjeevan Seera Chee Peng Lim Dahaman Ishak Harapajan Singh 《Applied Soft Computing》2013,13(12):4493-4507
In this paper, a hybrid soft computing model comprising the Fuzzy Min-Max (FMM) neural network and the Classification and Regression Tree (CART) for motor fault detection and diagnosis is described. Specifically, the hybrid model, known as FMM-CART, is used to detect and classify fault conditions of induction motors in both offline and online environments. A series of experiments is conducted, whereby the Motor Current Signature Analysis (MCSA) method is applied to form a database containing stator current signatures under different motor conditions. The signal harmonics from the power spectral density (PSD) are extracted, and used as the discriminative input features for fault classification with FMM-CART. Three main induction motor conditions, viz. broken rotor bars, stator winding faults, and unbalanced supply, are used to evaluate the effectiveness of FMM-CART. The results indicate that FMM-CART is able to detect motor faults in the early stage, in order to avoid further damage to the induction motor as well as the overall machine or system that uses the motor in its operations. 相似文献
106.
This article deals with performance evaluation of the discrete ordinates method in terms of its capacity to provide accurate results in solving radiation mode problems with different complexities. The problem formulation is done keeping in view the heat transfer process in an evaporator used in a coal-based thermal power station. The hot gas mass in the evaporator is assumed to be a heat source with two different shapes, spherical and conical. The evaporator walls that are covered with a water cooling jacket are modeled with a convective boundary condition. The gas is assumed to be gray and absorbing–emitting. The solution of the radiative transport equation is carried out using the discrete ordinates method. Parametric studies are performed for a wide range of aspect ratio, extinction coefficient, and convective heat transfer coefficient. The code is validated by comparing the result of discrete ordinates method with the exact and the discrete transfer method for nonradiative as well as radiative equilibrium conditions. 相似文献
107.
108.
Chee Sun Won 《Multidimensional Systems and Signal Processing》2013,24(2):221-233
As a transition stage from a conventional 2D TV to a full stereoscopic 3D TV system, a frame-compatible format of fitting stereoscopic left and right images to a single frame of the existing 2D TV is required to utilize existing codec and transmission infrastructure. To meet this requirement, a frame-compatible top-bottom packing with a horizontal line offset is proposed, where the vertical resolutions of the stereoscopic left and right images are reduced by half. Then, the optimal interpolation mode for each line segment of the sub-sampled horizontal line is determined by exploiting parallax-compensated data as well as undeleted neighboring upper and lower horizontal lines. At the receiver, the discarded horizontal lines for the left and right images are reconstructed by the interpolation modes provided by the sender. Experimental results show that the proposed algorithm improves the PSNR as much as 1.5–3dB comparing to conventional interpolation filters. 相似文献
109.
BACKGROUND: Whether or not tumor response to chemotherapy-sensitized radiation therapy (CTRT) for head and neck cancer leads to an improved outcome is unknown. METHODS: Forty patients who received preoperative cisplatin plus simultaneous radiotherapy for operable stage III and IV head and neck cancer were reviewed retrospectively regarding clinical demographics, staging, and survival status. RESULTS: Twenty-one (57%) patients had a histologic complete response (HCR) and 16 (43%) had a partial (PR) (9) or clinical complete (7) response (CCR). Tumor response of N1 versus N2-3 nodal disease showed 6 (75%) HCR and 4 (25%). Five-year disease-free survival overall was 82% for HCR versus 38% for PR/CCR (P <0.05). Disease-specific 5-year survival was 100% for HCR versus 27% for PR/CCR (P <0.002). CONCLUSIONS: Histologic complete response to CTRT for head and neck cancer is associated with increased survival and encouraging disease-free status. Response to CTRT is inversely proportional to lymphatic tumor load. 相似文献
110.
This paper presented design concepts to improve stroke magnification and to retain high torsional frequencies for piezoelectrically actuated suspension. Flexural rotation is employed to enhance stroke magnification at the dimple point of a load beam. As such, the two piezoelectric push-pull elements can be placed apart to make room for stiffening base portion of the load beam while attaining an adequate level of stroke. As a stiffening structure, an extended base plate is deployed to raise the torsional frequency of the actuated suspensions. The improved performances were verified numerically and experimentally. Also, prototypes in accordance to the present design concepts were fabricated and tested. 相似文献