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A Sagnac loop liquid refractive index sensor is proposed based on SMF-Tapered TCF-SMF (STS) and FBG. In the refractive index range of 1.333-1.3465 and 1.3515-1.363, the sensitivity is 5521.6nm/RIU and 7173.8nm/RIU, respectively. By cascading FBG, the random fluctuation of wavelength is reduced from±0.862nm to 0.004nm. It can effectively filter out part of the cladding mode and improve the stability of the sensor.

To improve the accuracy of wind speed forecasting, a new-type hybrid optimization algorithm, called CWPSO that integrates spiral updating mechanism of whale optimization algorithm (WOA) and chaos theory into particle swarm optimization (PSO), is put forward to optimize the weights and bias of BPNN. CWPSO can ameliorate the shortcoming of dropping in part optimization. Moreover, to reduce the negative impact of original data on prediction accuracy, adaptive singular spectrum analysis (ISSA) is used to remove the noise to put up the quality of the data. Finally, the performance of prediction model, which is ISSA-CWPSO-BPNN, is analyzed based on two cases. By comparing BPNN optimized with different algorithms, the effectiveness of CWPSO algorithm in improving the precision of wind speed forecasting is demonstrated.

An air pressure sensor is demonstrated based on a closed micro-cavity F-P (Fabry-Perot) optical fiber interferent sensing structure. The interferent wavelengths present red-shift with the air pressure increase. Its sensing sensitivity can get 1.271nm/MPa for the linear fitting of the experiment results.

In this paper, a kind of theoretical method of how to find out the dominant cladding modes in the all in-fiber interferometer is proposed. The relationship between the cladding modes spatial frequency and its modal order and sensing optical fiber length are simulated. It can be found that the fiber length increasing can make the value of the dominant cladding spatial frequency linearly increase. The order of the dominant cladding modes are increasing with fiber length. With the sensing optical fiber length increasing, some higher order cladding modes are excited and participate in the interference spectrum of the interferometer, which makes the fringe spacing of the interference spectrum finer.

According to the environment of Chinese deep sea mining area, the influence from the ship and the miner on the sea bed is analyzed, and the coordinated working mode of the ship and the miner is proposed. Meanwhile, the working path of the miner is determined. Considering the safe areas of the ship, miner and the buffer, the relative distance between the ship and the miner, that is 240 meters, is presented as the coordinated control target. Also, the saddle shape of the flexible hose, which ensure the productivity of the transportation, can be guaranteed. A simple PID control strategy is put forward and the model of control system is ascertained. Through along and adverse current simulations, the efficiency and accuracy of the presented coordinated control strategy is proved.

A droplet based microfluidic system encapsulating PCR reagent into alginate beads as a new digital PCR solution has been developed, which avoided droplet coalescence and enabled efficient DNA amplification and high-throughput fluorescent imaging. We also compared two trapping methods using hydrodynamic traps and micro-sieves, and indicated the advantages of latter for higher trapping rate and no droplet clogging. These results provide new insights and tools for on-chip digital PCR and are expected to attract broad interest for applications in droplet microfluidics.

Action recognition has been one of the most popular fields of computer vision. This paper presents a novel approach to action recognition problem using the dimension reduction method, local fisher discriminant analysis, to reduce the dimension of feature descriptors as the preprocessing step after feature extraction. We propose to use sparse matrix and randomized kd-tree to modify and accelerate the standard local fisher discriminant analysis and propose the modified local fisher discriminant analysis. We also propose an effective feature encoding called mix encoding to combine fisher vector encoding and locality-constrained linear coding to obtain video representations. The experiments show the methods clearly improve the recognition accuracy. Experimental results show our method outperforms our baseline method and can be the state of the art in the KTH dataset.

Thermally induced motion of flexible solar panel have significant impact on attitude dynamics and control when the spacecraft experience eclipse transitions. Based on angular momentum theorem thermally induced attitude dynamics of rigid hub with a flexible solar panel is developed. The principle of thermally induced vibration is explained. Thermally induced disturbance toque which initiates attitude error of control system is obtained. Flexible modal response is analyzed with different position of solar panel when satellite enter or exit eclipse. Numerical simulations illustrate that thermally induced disturbance toque mainly distort yaw and roll axis attitude of spacecraft.

Finding correspondences between pair of images of the same scene is a key problem in computer vision. When matching images undergo viewpoint change, partial occlusion, clutters and illumination change, there will be a lot of mismatches due to the limited repeatability and discriminative power of features. In this paper, we propose a robust matching algorithm that can remove false matches and propagate the correct ones to obtain more matches, thus improve the matching accuracy. Firstly, extract SURF (Speeded Up Robust Features) descriptors from the input two images, which can be used to build the proximity matrix. Then perform SVD(Singular Value Decomposition) on the proximity matrix to obtain the initial matches. Thirdly, refine the initial matches by the unique property of Delaunay triangulation that can produce the maximum clique of the two Delaunay graph. Finally, recover the lost matches with the constraint of dual graph of Voronoi. Experimental results on Oxford datasets indicate that our algorithm can improve the match performance compared to the RANSAC-based method.

We propose a novel, facile and low-cost method to prepare rewritable coatings with nanoparticles buried in gelatin-alginate hydrogel layer using water as the ink. Firstly, polystyrene-co-acrylic acid (PS-co-AA) nanoparticles mixed with gelatin were coated on various substrates such as microscope slides, plastics or black paper, and appeared white after water sprayed. The transmittance from transparency to opaqueness was irreversible in the inked regions even after the complete water evaporation. It was believed that PS nanoparticles immigrated from the bulk of gelatin network to its surfaces due to the Brownian motion. When the gelatin was swollen by water, the nanoparticles stuck to the surfaces after water evaporation. Secondly, to testify the principle, we further coated additional gelatin-alginate hydrogel layer on the top to prevent the immigration of nanoparticles to outer surfaces. It was found that ink marks can be erased after water evaporation, and such write-and-erase process can be repeated multiple times with excellent performances. These results showed the potentials of the rewritable hydrogel coatings in anti-counterfeiting and biosensing applications.

This paper presents a hand gesture recognition system as a part of our virtual reality system called non-contact flight auxiliary (NCFAC) system. The system is developed using Bayesian neural network to translate hand gestures to corresponding commands and utilizes one hand gesture to prepare for collision detection. Cyberglove sensory glove and Flock of Birds motion tracker are applied to this system to extract hand features. The Bayesian neural network model is trained and tested with different sample groups. Experiment shows that our system is able to recognize 16 kinds of hand gestures with the accuracy of 95.6% and greater generalization capability. The system can also be extended and use other algorithms for future works.

Thermally induced motion of flexible solar panel have significant impact on attitude dynamics and control when the spacecraft experience eclipse transitions. Based on two analyses methods thermally induced attitude dynamics of a rigid hub with flexible beam is developed. The principle of thermally induced vibration is explained. Thermally induced disturbance toque which initiates attitude error of control system is obtained. The effects of key structural parameters on thermally induced attitude disturbance are investigated. A stability criterion of thermally induced motion including the effect of the spacecraft is established related to structural damping, solar incident angle, and the ratio of structural and thermal response times. Numerical simulations illustrate that thermally induced disturbance distort the attitude of spacecraft and larger value of structural damping; larger difference between structural and thermal response times are likely to voiding thermal flutter and unstable motion of the spacecraft.

Release control plays an important role on the performance of a semiconductor wafer fabrication facility. Comparing to common release control strategies (such as FIFO, EDD, SA, CONWIP, WR, and WIPCTRL), a new workload regulating policy (abbreviated as WRELM), with a dynamic critical value on the bottleneck obtained by an extreme learning machine, is proposed. WRELM is validated and verified by a simulation model from a real 6 inch fab. The simulation results show that WRELM improves the throughput by 4.02% and decrease the mean cycle time by 15.40% comparing to those of common WR.

To the question of the carrier synchronization based on third-order phase-locked loops in the high dynamic environment. First, the paper verifies that the loop-filter with the overlap zeros tructure has the best performance through simulation, which increases about 2.5 to 1dB in noise compared with the other two kinds of structures. Then, in consideration of a long pull-in time to track high dynamic signals for the PLL, the paper proposes a fast phase lock algorithm based on third-order PLL with the overlap zero structure. Finally, The result shows that the algorithm significantly reduced the pull-in time about 40%~70%.

By measuring the transient photocurrents we study the charge carrier dynamics in regioregular poly(3-hexylthiophene) (P3HT): 6,6-phenyl-C61-butyric acid methyl ester (PCBM), and poly(3-hexylthiophene) thiophene thienopyrazine (P3HTT-TP):PCBM bulk heterojunction (BHJ) solar cells. The latter is based on a novel “semi-random” copolymer and exhibits broad spectral absorption. We observe that the charge carrier transport in P3HTT-TP:PCBM is more imbalanced than that of P3HT:PCBM. Voltage dependent photocurrent transients indicate that P3HT:PCBM has longer carrier lifetimes than P3HTT-TP:PCBM. Light intensity dependent open-circuit voltage measurements show stronger monomolecular recombination in P3HTT-TP:PCBM. The unfavorable charge carrier transport may be one of the reasons for the low power conversion efficiency of P3HTT-TP:PCBM BHJ solar cells.

This paper presents a systematic study of key physical mechanisms in organic polymer/fullerene solar cells that determine the power conversion efficiency. The carrier loss at each step is calculated or measured. We compare poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly(3-hexylthiophene)-thiophene-thienopyrazine (P3HTT-TP)/PCBM solar cells. The latter polymer, P3HTT-TP, is a novel low-bandgap “semi-random” alkythiophene-based copolymer with a broader absorption spectrum than P3HT. Absorption, a significant loss factor for all polymer/fullerene solar cells, was studied using external quantum efficiency and absorption spectroscopy measurements and modeled with a multi-layer transfer-matrix theory. In addition, hole traps inside the polymers play an important role in polaron pair dissociation and free charge transport. It was found that this is particularly deleterious for P3HTT-TP/PCBM.

The purpose of this paper is to study the problem about financial risk early-warning of listed companies in the supply chain environment. Based on a comprehensive overview of the issue of listed companies' financial risk early warning, it tries to build a warning model of the core enterprise's financial risk in the supply chain environment, and does a case study to test its practicality. The model, which integrates a number of mature theories and early-warning models, uses the method of modern technology, statistical tools and financial risk management theory. This paper studies the financial early-warning methods of listed companies in supply chain environment, and provides a comprehensive early-warning program, which can identify the potential risks. The improved traditional early-warning model is introduced into a new area. The system of financial indexes and non-financial indexes are re-established, considering the particularity of financial risks in supply chain environment, indexes related are reselected.

In this paper, we present a novel computing paradigm using a non-equilibrium electronic ratchet which is capable of driving current in the absence of an applied drain bias. By using a time varying, spatially asymmetric potential, we demonstrate that it is possible to create a net current from drift-diffusion processes of charge carriers. This is especially useful in reducing static dissipation encountered in conventional logic circuits. In addition, since the electronic ratchet acts as voltage-controlled current source, we find that the dynamic dissipation associated with charging/discharging of load capacitors is also decreased. Furthermore, we show that the ratchet device is naturally amenable to a dissipation reduction technique known as adiabatic clocking. Because of the unique charging mechanism of the ratchet, timing constraints on logic inputs—an important drawback of conventional adiabatic circuits—are not needed to achieve adiabatic computation.

Through further analysis of free cash flow and over-investment and from the point of Corporate Governance, this paper establishes the model of shareholder, director board and supervisory board to the over-investment of manager. The relationship among Corporate Governance, free cash flow and over-investment is examined. The results of this study has findings that shareholder, director board and supervisory board not effective restrict the over-investment of manager.

Models of pricing based on Bertrand competition between manufacturer and distributor are discussed under Dual-channel Environment. A system consisting of a manufacturer, a distributor and customers is considered, in which the manufacturer can sell products to the distributor, who, in turn, sells the products to customers through traditional channel, or the manufacturer can transact directly with the customers in an electronic manner. In the Bertrand game setting, the manufacturer and the retailer decide simultaneously the prices of products.The manufacturer and the retailer establish models with the respective objection of maximizing expected profit, and transaction cost is considered in these models. The manufacturer regards the price of products sold to retailer through traditional and online channels as decision variables, while the retailer's decision variable is the price of products sold to customers. At last, the numerical examples are given to show application of pricing model based on Bertrand game.

Environmental issues become the current urgent problems to be solved. This paper summarizes the concept and theoretical development of the natural capital, and advocacy to establish the concepts which are that facing up to natural capital, respecting the natural capital, protection of natural capital. On this basis, it is proposed that the environmental capacity is considered as an essential production factor for enterprise, and environmental production factor theory is deemed as the point to achieve green accounting.

The electrocorticogram (ECoG) is a kind of signal source that can be classified for making use of a human brain computer interface (BCI) field. The feature extraction is crucial for increasing classification accuracy rate. In this paper, Power Spectral Density is used for the selection of the optimal electrodes. Common spatial pattern (CSP) algorithm is used for feature extraction, and the nonlinear classification of motor imagery with support vector machines (SVM).The classification accuracy rate of 83% is achieved on Data set I of BCI Competition III.

Since the concept of environment production factor proposed, it has been widely concerned. However, it is lacking for the study on its supply, demand curve and price setting model. Several questions have been discussed in this paper. First, we analyze the supply curve without considering reserved self-using. Second, according to its concept and characteristics, we get its “vertical ladle” supply curve in practice. Finally, combine the demand curve of environment production factor; we get its equilibrium price under condition of perfect competition.

The throughput and reliability indexes of broadcasting protocol is related to contention windows valve and contending nodes in vehicular ad networks. To find suitable contention window value which can optimize the throughput and reliability of broadcasting protocol, this paper propose theoretical analytic model to analysis the relationship between the throughput and the reliability. So, the analysis results show that the proposed analytic model and optimization contention windows value can enhance the system throughput and ensure reliability of information broadcasting.

Present day CMOS transistors operate by thermionic emission of electrons over a gate tunable barrier. The fundamental switching energy for each such switching event can be derived from equilibrium thermodynamic considerations. While clever ways can sometimes mitigate the power budget, more often than not, this involves trade-offs with short channel effects (variability), on-off ratio (reliability) and mobility (switching speed). We discuss switching paradigms that venture beyond the near-equilibrium operation of transistors involving the absence or presence of charges as the digital switching bits. To this end, a few case studies are presented. Dipolar switching is invoked as an example to show how gating non-electronic degrees of freedom can reduce the subthreshold swing below the textbook limit by acting as an added cut-off filter on the current. We discuss how new state variables may be engineered into a CMOS platform to enable such non-electronic switching. Another, completely different direction involves non-equilibrium switching, such as a ratchet that allows us to move charges unidirectionally without a drain bias, by using instead an always present AC clock signal adiabatically coupled with the gate.

The problem how a manager motivate producers to reduce product costs under asymmetric information is discussed on a basis of principal-agent theory. Under asymmetric information, manager can not monitor producers' effort to reduce costs; therefore, manager needs to motivate producers. The manager determines a contractual basic cost according to his own requirement and producers'self-reported cost, and establishes a model to maximize manager's expected utility under the conditions of producers' individual rationality constraint and incentive compatibility constraint. The model uses incentive and punishment coefficient as decision variables and the evolutionary programming algorithm is used to do the simulation.

In order to simulate the real multi-layer plate structure, a DOF coupling algorithm of nodes and inner points of element based on constraint equation is proposed in this paper. The main idea of the proposed algorithm is let the DOF of the nodes on the constraint surface coupling with the DOF of the inner point of the element on the objective surface which can be expressed by the nodes DOF. By this way, the coupling formula is a multi-nodes constraint equation in fact. It can be seen that the von-mises stress distribution is more reasonable and reliable and meet the analysis needs comparing with the computed results by using the method of direct coupling nodes and the element type of MPC 184???

Before a synchronous generator puts into operation, it may be suddenly connected to the grid by accident and led to be an asynchronous operation under high-slip condition, that can cause serious damage to the rotor. This paper analyzes the rotor wedge temperature under above condition, calculation results show that the temperature will increase rapidly, and then the mechanical strength of the rotor wedge will lose, finally, the rotor wedge may escape from the rotor for centrifugal force.

—Object reconstruction is one of the most important topics in computer vision due to its wide field of application. Reverse engineering has an increasing need for reconstruction of stereo parts. A system for reconstruction three dimensional (3-D) object’s surface from its 2-D views using a coded structured light combining with the epipolar geometry that exists between the stereo image pair is presented. A set of multiple gray coded patterns and a set of sine wave patterns are combined to form a single "Gray Code Composite Pattern" and a single "Phase Shift Composite Pattern" respectively. These two structured light patterns are projected onto the target object through a DLP projector and the distorted strips patterns produced by its surface are captured by two CCD cameras. By demodulating the distorted patterns and adding epipolar constraints the match points between the image pair are found out and then the target object’s 3-D point’s coordinates on the surface are obtained. The system shows excellent linearity and the results shows good resolution.

The process, to model a garment design system using object-oriented technology based on UML, is introduced in this paper. A new method is applied in developing garment design system, which is called object-oriented UML, different from the traditional flow-based C language method. From core to edge, a screw tape method is used to design the functions of the system with a clear hierarchy, providing a new and recommendable method for garment design. Garment design platform is mainly composed by two modules: the garment selecting module which is based on different human body size and shape; the geometric designing module which is used to design the garments? concrete shape.

We describe, in this paper, a multiway partitioning algorithm for parallel gate level Verilog simulation. The algorithm is an extension of a multi-level algorithm which only creates two partitions. Like its predecessor, it takes advantage of the design hierarchy present in a Verilog circuit design. The information it makes use of is contained in the modules and their instances. The algorithm makes use of a hypergraph model of the Verilog design in which a vertex in the hypergraph represents a module instance. Our new algorithm relies upon a metric whose function is to balance the load and the communications between the modules of the Verilog design. pre-simulation is used to to evaluate the partitioning metric. When compared to hMetis, a well known multilevel partitioning algorithm, our algorithm produces a superior speedup and a reduced cut-size.

With the rapid development of information technology, urban planning visualization is more and more concerned. This paper describes 3D technologies associated with urban planning, analysis the feasibility of urban planning visualization, and some core techniques of 3D urban planning system based on virtual reality (VR) and geographic information system (GIS). 3D model generation, communication methods between GIS and 3D scene and system integration are also discussed in this paper. The example system shows that it is helpful for designers to achieve 2D and 3D urban information and make decisions of urban planning schemes.

This paper presents a novel non-rigid registration method for augmented reality applications using AAM and factorization method. The method can be divided into two stages: offline construction of 3D shape basis and online estimation of the 3D pose parameters together with the 3D shape coefficients. In offline stage, we get the training data with the use of the AAM algorithm, then we use factorization method to obtain the object 3D shape basis set from image sequences. In online stage, given an initial 3D shape coefficients and the rotation matrix, we can get the non-rigid object coordinates under the world coordinate systems by projecting the 3D points which are the linear combination of the 3D shape basis to the 2D image. Then we use Levenberg-Marquardt algorithm to optimize the 3D shape coefficients and the 3D pose parameters simultaneously. Some experimental results demonstrate this method is effective and useful for augmented reality applications.

Visibility culling is a fundamental problem in computer graphics. By combining object-space coherence with image-space coherence, this paper presents a novel algorithm for speeding up complex models rendering. The algorithm is based on the new concept of occupancy proportion (OP), which offers a simple, fast and efficient approach to visibility culling. We exploit the hardware accelerator character, and proposed an asynchronous occlusion queries method which significantly alleviates the affection caused by occlusion queries latency. The algorithm utilizes a hierarchy tree structure containing objects in the scene. The method in the paper can be easily integrated into majority visibility culling algorithms. The algorithm benefits for estimating object visibility and improves the efficiency of object visibility determination. Methodology and implementation details are provided, and experimental results demonstrate that the algorithm can obtain higher rendering efficiency than conservative object bounding box occlusion query method. The algorithm is suited for arbitrary structure scenes especially for slender scenes.

VANETs (vehicular ad hoc networks) are emerging as a new network environment for intelligent transportation systems. Many of the applications built for VANETs will depend on the communications technology that vehicles exchange the information by using wireless LAN without any base stations. So, it is important to provide strict delay guarantees and high throughput performance on wireless vehicular mobility environments. However, legacy IEEE802.11 DCF protocol lacks support for quality of service differentiation and degraded channel utilization. This paper presents a cross layer sheme of fragmentation and priority scheduling, which is approach focusing on time varying property of the wireless channel and networks load condition. Simulation results show that our cross layer scheme may provide timely delivery guarantees to different classed of real time date traffic, and increase the vehicular ad hoc networks throughput.