摘要：
Phosphorus doped graphitic carbon nitride (g-C3N4) was easily synthesized using ammonium hexafluorophosphate (NH4PF6) as phosphorus source, and ammonium thiocyanate (NH4SCN) as g-C3N4 precutsor, through a direct thermal co-polycondensation procedure. The obtained phosphorus doped g-C3N4 was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FTIR), UV-vis diffuse reflectance absorption spectra (UV-DRS), photoelectrochemical measurement and photoluminescence spectra (PL). The photocatalytic activities of phosphorus doped g-C3N4 samples were evaluated by degradation of Rhodamine B (RhB) solution under visible light irradiation. The results showed that the phosphorus doped g-C3N4 had a superior photocatalytic activity than that of pristine g-C3N4, attributing to the phosphorus atoms substituting carbon atoms of g-C3N4 frameworks to result in light harvesting enhancement and delocalized IT-conjugated system of this copolymer, beneficial for the increase of photocatalytic performance. The photoelectrochemical measurements also verified that the charge carrier separation efficiency was promoted by phosphorus doping g-C3N4. Moreover, the tests of radical scavengers demonstrated that the holes (h(+)) and superoxide radicals (O-center dot(2)-) were the main active species for the degradation of RhB. (C) 2016 Elsevier B.V. All rights reserved.
摘要：
The catalytic steam gasification of municipal solid waste (MSW) for hydrogen-rich fuel gas production was experimentally investigated in a combined fixed bed reactor using the newly developed tri-metallic catalyst. The results indicated that the supported tri-metallic catalyst had a high activity of cracking tar and hydrocarbons, upgrading the gas quality, as well as yielding a high hydrogen production in catalytic steam gasification of municipal solid waste. A series of experiments have been performed to explore the effects of catalyst presence, catalyst to MSW mass ratio (C/M), catalytic temperature, steam to MSW ratio (S/M) and MSW particle size on the composition and yield of gasification gases. The experiments demonstrated that temperature was the most important factor in this process; higher temperature contributed to more hydrogen production and gas yield. Varying catalyst to MSW mass ratio (C/M) demonstrated complex effects on gas yield and composition of MSW gasification and an optimal value of 0.5 was found in the present study. Comparing with MSW catalytic gasification, the introduction of steam improved gas quality and yield, the optimal value of S/M was found to be 1.33 under the present operating condition. It was also shown that a smaller particle size was more favorable for gas quality and yield. (C) 2012 Elsevier Ltd. All rights reserved.
摘要：
The MoS2/CdS composites with layered MoS2 loaded on uniform CdS nanospheres were synthesized by a two-step process combination hydrothermal and solvothermal treatments, and then applied in photocatalytic hydrogen evolution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, UV-vis diffuse reflectance absorption spectra (UV-DRS), nitrogen adsorption-desorption measurement, photoluminescence spectra (PL) and photoelectrochemical tests. The effects of loading contents of MoS2 in the composites on the photocatalytic H-2 evolution activity were comparatively investigated with 0.45 mol L-1 Na2S and 0.55 mol L-1 Na2SO3 as sacrificial agents. The results showed that the 5 wt% MoS2/CdS composite could achieve the highest photocatalytic H-2 evolution rate of 372 mu mol h(-1) and apparent quantum efficiency (AQE) about 7.31% under 420 nm monochromatic light irradiation. The remarkably enhanced photocatalytic activity of MoS2/CdS composite could be attributed to the effective transfer and separation of photogenerated charge carriers, and MoS2 being as a cocatalyst to facilitating photocatalytic H-2 evolution reaction. A tentative mechanism of MoS2/CdS composites as photocatalysts for H-2 evolution was proposed. (C) 2017 Published by Elsevier B.V.
摘要：
To be able to predict tribological properties of new lubricant additives as well as clarify lubricating mechanisms, one needs to study the relationship between structures of lubricant additives and their lubricating properties. With a focus on estimating antiwear properties of some heterocyclic additives, we use the quantitative structure tribo-ability relationship (QSTR) model to predict tribological data, which introduces the idea of computer-aided design into tribology. This is combined with back propagation neural network (BPNN), a machine-learning method that offers simplicity and robustness. This study determined the feasibility and predictability of developing the BPNN QSTR model to estimate lubricant additive antiwear properties. For 36 additives, 90 structural descriptors, such as octanol-water partition coefficient, quantum indices, 2D topological indices, and 3D Jurs descriptors, were included as BPNN inputs. Antiwear parameters include wear-scar diameters under three loads. Leave-one-out cross-validation was performed to evaluate accuracy and robustness of this BPNN QSTR model. We also evaluate the descriptor sensitivities, from which we can determine the effects of each descriptor and clarify wearing mechanisms. Given a positive assessment, this method warrants further development and validated integration with other tribological properties. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.
会议名称：
IEEE International Conference on Security, Pattern Analysis, and Cybernetics (SPAC)
会议时间：
OCT 18-19, 2014
会议地点：
Huazhong Univ Sci & Technol, Wuhan, PEOPLES R CHINA
会议主办单位：
[Li, Linyu;Zeng, Wu;Zhou, Long] Wuhan Polytech Univ, Sch Elect & Elect Engn, Wuhan 430023, Peoples R China.^[Hong, Zhiguo] Commun Univ China, Fac Sci & Engn, Beijing 100024, Peoples R China.^[Hong, Zhiguo] Minist Culture, Key Lab Acoust Visual Technol & Intelligent Contr, Beijing 100024, Peoples R China.^[Hong, Zhiguo] Beijing Key Lab Modern Entertainment Technol, Beijing 100024, Peoples R China.
关键词：
Social network;Petri Nets;Performance evaluation;ON/OFF model;Traffic
摘要：
A social network is a social structure made up of a set of social actors (such as individuals or organizations) and a set of the dyadic ties between these actors. By contrast, for the fixed time duration the size of digital video would be much bigger than that of digital sound. Consequently, providers of social network services can offer real-time chatting among users which could offer satisfactory experiences for users. As one of the most popular content-based social network services (SNS), chatting service plays an important role in current big data era. Also average data packets' transmission via networks is another significant traffic. So how to offer satisfactory Quality of Service (QoS) for users is the key problem which will be solved for SNS provider. For real time communication among users, end-to-end time delay seems to be critical in user's experience. Therefore modeling and evaluating social network systems is an important and urgent issue which offers quantitative basis of SNS with high quality for users. For social network system, the scalability and robust are important for both service provider and users under the circumstance of a large number of users. On the basis of performance evaluation of social network system of one user case, we construct the SPN model and conduct numerical analysis to discover and report the performance with the addition of users. By taking hybrid traffic containing voice and data into account, this paper constructed a Stochastic Petri Net (SPN) model for data and ON/OFF voice traffic for social network system. Then, average time delay of the system was analyzed and model-based simulation is conducted with Stochastic Petri Net Package (SPNP) 6.0. Furthermore, for different parameters of burst rate, idle rate, number of data packets, traffic load and buffer size, variation trends on average time delay are derived thereby. On the basis of the work in this paper, further research on heterogeneous objects of social network systems can be carried on. (C) 2016 Elsevier B.V. All rights reserved.
关键词：
Cybernetics;Groups;Decision making;Group decision support systems
摘要：
This paper was supported by the Sub‐project of the national “985 Project” (Grant No. 985 hust‐13011) and Sub‐project of the National Natural Science Foundation of China (Grant No. 79970025(S1)). Purpose – The purpose of this paper is to propose a new group decision‐making approach, which can only use simple mathematical calculations to perform a group decision‐making task. Design/methodology/approach – The large column and large row (LCLR) method is designed and applied. Findings – The paper finds four propositions to support LCLR methods to be a simple and effectual means for group decision making. Research limitations/implications – The aggregated matrix constructed in LCLR methods should be generated from non‐contradictory circles. Practical implications – Effective group decision‐making results can be obtained by easily used methods, not necessarily by using complex mathematics technology to conduct the task. Originality/value – The new approach based on LCLR methods proposed in this paper may be one of the most easily used and effective means for group decision making.
摘要：
Because of the low tensile strength of brittle materials, the tensile fracture simulation is of great importance to the numerical study of the failure procedure of these materials. A simple element-splitting model is proposed in this paper to simulate the tensile fracture procedure based on finite element method (FEM). As an application of this model, the fracture procedure of a doughnut-shaped specimen is simulated and the numerical results are compared with the deformation fields' evolution from an experiment on a granite specimen with the same geometry and same loading process. Results from the experiment verified the validation of the simulation model. (C) 2009 Elsevier B.V. All rights reserved.
会议名称：
International Workshop on Modeling and Simulation of Food Processing and Operations held during the Modeling and Applied Simulation (MAS) Conference
关键词：
non-fried instant noodles;mathematical modeling;convective air drying characteristics;rehydration attributes;microstructure
摘要：
Convective air drying characteristics and qualities of non-fried instant noodles at five temperatures from 80 to 120 degrees C and velocities of 1.0, 2.0 and 3.0 m/s were investigated. Different mathematical models were fitted to study the drying behaviors and the Logarithmic model was the most adequate in describing the drying tests. Results showed that the drying process occurred in a falling rate periods and the effective moisture diffusivity increased with temperature and velocity, ranging from 4.41 x 10(-8) to 1.75 x 10(-7) m(2)/s with an activation energy of 16.73 kJ/mol. The rehydration attributes changed with both velocity and temperature. Increasing temperature and velocity decreased hardness, increased cohesiveness and resilience generally while had no impact on springiness. Drying temperature greatly influenced the color of noodles, whereas velocity displayed no significant effect. Microstructural analysis indicated that noodle presented hollow and porous structure with numerous and small voids, which might partly explain their distinct behaviors.
摘要：
This paper presents an electrocardiographic signal classification method. This method first uses a revised locally linear embedding (LLE) algorithm to perform dimension reduction to the Electrocardiography (ECG) data. This manifold distance measurement-based LLE was proposed to solve the defect of conventional LLE that, due to the use of Euclidean distance, it could not properly measure the distance between high-dimensional samples. Using this revised LLE algorithm for the dimension reduction of data, more original data information could be retained, and the features of high-dimensional ECG data could be more effectively extracted, thereby improving the classification accuracy. The method then adopts kernel-based fuzzy C-means clustering algorithm to perform ECG signal classification. Classification tests on four common types of ECG signals-from the MIT-BIN database showed that the proposed method reached an overall accuracy of 99%.
关键词：
DIRECT DIGITAL FREQUENCY SYNTHESIZER;MEMS;QUARTZ CRYSTAL;RESONANCE FREQUENCY;RESONANCE IMPEDANCE;VACUUM DEGREE;VACUUM PACKAGING
摘要：
A platform is proposed in this paper for fundamental study of the miniaturized MEMS packaging on its long term performance such as actual vacuum level maintaining inside the packaging cavity, and durability of the packaging shell subjected to cycling thermal loading. In particular, a sensor composed of quartz crystal is introduced for vacuum measurement. The quartz crystal is placed in the internal cavity of the MEMS packaging and is excited by an exciting source which is formed by Direct Digital Synthesizer (DDS). The voltage signal from both ends of the quartz crystal is outputed to comparison circuits to compare the phase and amplitude of the signal. Then it is transmitted to the SCM after AD conversion for measuring and monitoring the vacuum degree of internal cavity of the MEMS package after processing and calibration. It has been found that the actual vacuum level within the cavity is much lower than the applied vacuum level in the packaging chamber. The proposed vacuum packaging shell with double walls has been found to provide perfect structure to help maintain long life when the packaging is subjected to the cycling thermal loading.
会议主办单位：
[Sano, Y.;Nakayama, A.] Shizuoka Univ, Naka Ku, Hamamatsu, Shizuoka 4328561, Japan.^[Horibe, A.;Haruki, N.] Okayama Univ, Kita Ku, Okayama 7008530, Japan.^[Nakayama, A.] Wuhan Polytech Univ, Wuhan 430023, Hubei, Peoples R China.
关键词：
porous media;mass transfer and drying;reverse osmosis;spiral-wound module
摘要：
A mathematical model for spiral-wound reverse osmosis systems has been established using a porous media approach. Transport processes through membranes were investigated, fully taking account of concentration polarization associated with spiral-wound reverse osmosis desalination systems. A set of the governing equations, namely, the continuity, momentum, and concentration equations, have been derived for three distinctive phases, namely, brine, permeate, and membrane phases, following the procedure previously proposed by Nakayama and Sano for the analysis of hollow-fiber desalination modules. The first-order differential equations in terms of the average velocity, pressure, and salt concentration for the brine phase are integrated with an algebraic equation for the permeate flow rate per unit volume in order to estimate the permeate salinity, flow rate, and pressure drop in spiral-wound reverse osmosis modules. The present analytical results agree fairly well with available experiment data reported by Avlonitis et al. [Desalination, 81: 191, 1991; 86: 273, 1992; 89: 227, 1993; 203: 218, 2007; Sep. Sci. Technol., 40: 2663, 2005], substantiating the validity of the governing equations based on the porous media approach for spiral-wound reverse osmosis systems. The present analysis reveals that there exists an optimal brine pressure for attaining the maximum permeate flow rate for a given pumping power. The present model can be used to design spiral-wound reverse osmosis desalination systems without resorting to extensive finite difference calculations.
摘要：
From the generalized constitutive law of geo-material elastic-plastic model, the problem of model identification among one model type is transformed to a problem of parameter identification. So, using the new bionics algoritlun-Immune Evolutionary Programming (IEP) proposed by author recently, the elastic-plastic model identification among one model type is studied, and a new model identification method is proposed. At last, this method is verified by a numerical example. The results show that, this method can get the suitable geo-material model when only displacements are known.
摘要：
This paper proposes a kind of wavelet domain image digital watermarking technique using two-dimensional chaotic stream encryption and human visual model. A stream encryption algorithm based on two-dimensional Logistic chaotic map is researched and realized for meaningful grayscale watermarking image. The block embedding intensity is calculated and combined with the human visual model, so that the embedding and detection steps of encrypted binary watermark can be adaptively fulfilled in the wavelet coefficients of the host image. The experimental results have shown that this watermarking technique can endure regular digital image processing and have preferable performance.
关键词：
spectrophotometry;vanadium;5‐Br‐PADAP;stone coal ores;spectrophotométrie;vanadium;5‐Br‐PADAP;minerais rocheux de charbon
摘要：
A selective and sensitive spectrophotometric method has been developed for determining the total amount of vanadium in carbonaceous shales (stone coal ores). The method is based on the reaction of vanadium(V) with the chromophore reagent 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol (5‐Br‐PADAP) in the presence of hydrogen peroxide. In a 0.072 mol l−1 sulfuric acid medium, 5‐Br‐PADAP reacts with vanadium(V) to form a red‐violet complex with a maximum absorption peak at 596 nm with an apparent molar absorption coefficient of the complex of 8.45 × 104 l mol−1 cm−1. Beer's law was obeyed in the range 0–25 μg vanadium in 25 ml of solution, with a correlation coefficient of 0.9995. Interferences due to various non‐target ions were also investigated and high quantities of other common inorganic ions were tolerable. The method involved the dissolution of the ore sample by Na2O2 fusion, followed by filtering of the alkali solution after which Fe(III), Cu(II), Ni(II) and Co(II) etc. were effectively separated from the solution by precipitation in a NaOH solution. Selectivity was increased with the use of EDTA as a masking agent. The vanadium in ore samples was determined with a relative deviation (RSD) between 0.20 and 0.76%, and has been successfully applied to the determination of vanadium‐bearing stone coal ores. The results indicated that the accuracy of 5‐Br‐PADAP spectrophotometry is comparable with the ICP‐AES method. The characteristics of the method, i.e., simplicity, selectivity, sensitivity and rapid calibration, make it specially suitable for routine analysis. Une méthode spectrophotométrique sélective et sensible a été développée pour déterminer la concentration totale de vanadium dans les minerais rocheux de charbon. La méthode est basée sur la réaction du vanadium (V) avec l'agent coloré 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol (5‐Br‐PADAP) en présence de peroxyde d'hydrogéne. Dans une solution d'acide sulfurique, le 5‐Br‐PADAP réagit avec le vanadium pour former un complexe rouge violacé qui a son pic maximum d'absorption à 596 nm et un coefficient d'absorption molaire apparent de 8.45 × 104 l mol−1 cm−1. La loi de Beer est vérifiée entre 0 et 25 μg de vanadium dans 25 ml de solution, avec un coefficient de corrélation de 0.9995. Les interférences dues à différents ions parasites ont aussi été recherchées et d'importantes quantités des autres ions inorganiques communément trouvés se sont révélées tolérables. La méthode comprenait la mise en solution de l'échantillon de minerai par fusion avec Na2O2, suivie d'une filtration de la solution alcaline ensuite de quoi Fe(III), Cu(II), Ni(II) et Co(II) etc. ont étééliminés de la solution par précipitation dans une solution de NaOH. La sélectivité a été augmentée par l'utilisation de EDTA comme agent masquant. Le vanadium dans les minerais a été déterminé avec une déviation relative standard (RSD) comprise entre 0.20 et 0.76% et la méthode a été appliquée avec succés à la détermination du vanadium dans des minerais rocheux de charbon. Les résultats montrent que la précision de la spectrophotométrie de 5‐Br‐PADAP est comparable à celle obtenue avec l'ICP‐AES. Les caractéristiques de cette méthode, à savoir sa simplicité, sa sélectivité, sa sensibilité et sa calibration rapide en font une méthode particuliérement adaptée aux analyses de routine.
摘要：
The effect of impact damage is tightly relevant to structure survivability, experimental study on impact damage of structures is one of the most important measures that supply data for the evaluation of structure survivability. In this paper, some experimental studies on the damage of typical aircraft structure subjected to discrete low velocity impact are performed. Plexiglas (MDYB-3) is a typical material usually used in aeronautical engineering structures such as aircraft canopy windshield. For this aeronautical structure, preliminary studies on the relations among impact energy, impact damage and remaining strength of structure subjected to impact loading are conducted experimentally. In the impact experiments, free-fall dropping dart device with four different kinds of dart heads are used for the plate specimen of MDYB-3, the impact damages produced by different dart heads are figured by damage depth and damage area. Remaining tensile strength and fatigue life tests are implemented and the relationship between remaining strength of structures and impact damage is studied and discussed. Results obtained from these experiments are basic to further analysis and evaluation on structure survivability.
会议论文集名称：
Modelling and Simulation-World Academic Union
关键词：
signals separation;adaptive line enhancer;colored noise;fault diagnosis
摘要：
The rub failures between rotating and stationary parts in rotating machinery may contribute to vibration signals measured on the machine as the colored noise component. But, for the colored noise mixed in vibration signals, ordinary FFT or autoregressive (AR) spectrum analysis methods can't provide sufficient and reasonable spectra estimates. In this paper, we exploited Adaptive Line Enhancer (ALE) technique to separate the colored noise from vibration signals in the time domain. The capability of the technique was evaluated using Simulink for some simulated vibration signals composed of three sinusoids and an additive colored noise. The results show that the technique is capable of separating accurately colored noise even at a lower level of colored noise, and tracking the level variation of colored noise in simulated signals. Further experimental tests for actual complex vibration signals will be conducted to validate the technique.
摘要：
At the present time, the mechanics of seepage in fracture-cavity carbonate reservoir is not very clear. Fracture-cavity carbonate reservoir was simplified as regular fracture-cavity net model and rules of seepage in it were studied by numerical simulation based on Navier-Stokes equation (N-S equation). Results showed that flux exponentially increased along with the increase of fracture width but flux and diameter of cavity had linear relationship; the seepage in fracture-cavity also obeyed the Darcy's law, but the permeability was bigger than the fracture model's, which represented different performance of flow; fracture width had more impact to seepage than diameter of cavity.
