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This paper presents a new algorithm to retrieve 3D model on distance classification histogram. First, we select the certain number of random points on the model surface and compute the distance between two random points. Secondly, we sort the distance into two types which is based on the different geometry properties of these distance and construct the distance classification histogram. Finally, we measure the similarity of 3D models by comparing distance classification histogram. The experimental results on PSB show that our method has a good performance in precision and computational complication.

The numerical simulation of cavitation flow field in a Francis turbine runner with attached blades was conducted based on the no-slip mixture model in the Euler approach and the Singhal cavitation model. The RNG model after correcting viscosity and the pressure correction algorithm (SIMPLE) were supplemented. The distributions of the water-vapor volume fraction under non-design conditions were obtained. The results show that the method based on two-phase mixture model can be used to simulate the position and degree of cavitation flow in Francis turbine.

To study the effects of the nonhomogeneous material properties on the stress in an induction quenched crankshaft, the FEM model considering the nonhomogeneous material properties was established to simulate the stress in the crankshaft under the explosion pressure. Results showed that the nonhomogeneous properties almost didn’t vary the Mises stress distribution rule in the crankshaft. The maximum Mises stress, the ratio of the elastic modulus of the surface layer and the matrix followed a linear rule nearly. Moreover, the maximum Mises stress increased with the ratio. Besides, effect of elastic modulus distribution in the transition layer on the maximum stress could be ignored. To simplify the establishment of the FEM model, the elastic modulus could be set to either equal to the surface layer’s or the matrix’s.

Super-resolution image restoration technique can certainly increase the resolution of the obtained images without altering the system hardware conditions, which has become a research hotspot in the fields of remote sensing, military surveillance, public safety and medical imaging. The spatial domain algorithm has been studied widely and deeply, but it still has shortcomings and limitations. This paper studies the image degradation mechanism, establishes a precise image degradation process model, proposes an improved hybrid MAP-POCS restoration algorithm with using the Huber-Markov random field model as the priori probability model, which adds the convex sets constraints to the MAP estimation process and uses the peak signal to noise ratio (PSNR) to evaluate the recovery image quality. The simulation results show that the improved hybrid algorithm combines the only solution solving feature and noise reduction ability of the MAP method and strong prior knowledge utilized feature and flexibility of the POCS method, effectively ensures the convergence stability of the restoration and maintains the edge details of the restored image, enhances the effect of the super-resolution restoration.

Successfully developed of high-speed SCARA robot provides the possibility for fast handling. After analyzed the mechanical structure of SCARA robot, the kinematics equations were built to analyze forward and inverse kinematics problems based on modified D-H coordinate system theory. The trajectory planning was achieved by using the cubic polynomial interpolation method in joint space over the path points combined with motion parameters, the kinematics and trajectory planning were simulated by using matlab simulation platform. Simulation results show that robot parameter design is reasonable and the trajectory planning by interpolation calculation in joint space is feasible.

International Civil Aviation Organization (ICAO) is building a carbon dioxide standard for aircraft emissions. The CO2 standard is planning to be carried out by 2016 as the aviation emissions airworthiness standards, which will immediately influences the aircraft airworthiness certification. In this paper, the main context of the carbon dioxide standard for aircraft, basis for the establishment and metrics were studied. In addition, the metric system, the key point of CO2 emissions standards, has also been explained. Moreover, the implementation and criteria of the metric system was presented through computing and analyzing of the active-duty models. As a result, the CO2 emissions standard is aiming at improve the fuel efficiency and operational efficiency, which effectively reduce carbon emissions.

Looking for photonic crystals with wide absolute bandgaps is always a challenging, attractive and significant task for optics scientists and optics engineers. In this paper, a new square-lattice photonic crystal structure is proposed based on a unit cell with a hollow cylinder and cross connecting plates. It is demonstrated through plane wave expansion method to have wider absolute photonic bandgaps compared with others reported.

Massive Online Open Course which based on Open Educational Resource might be the most effective method to large-scale quality education, which can realize passive learning to active learning. Analyzing the status and shortages of Intelligent Answering System, propose and design an intelligent question answering system based on agent-model. System use software agents to implement and improve MOOC system’s Intelligent Answering System performance, which has capacity of natural language processing, and good versatility. It can provide an efficient online problem answer environment for thousands of learners, and can effectively promote students' autonomous learning and self-development.

A new type of two-dimensional square-lattice photonic crystal structure made of rotated square cylinders and cross thin plates is presented and numerically investigated using the plane-wave expansion method. The largest absolute photonic bandgap (APBG) reaches 14.3%. The proposed structure can have promising application for its large APBG and convenience in designing optical circuits.

Development of low-sulfur and Pb-free free cutting steel is significant because the use of S or Pb free-cutting steel can result in serious pollution. The hypoeutectoid graphitized free cutting steel was proposed. The graphitizaion is difficult due to slow graphitization process, so it is curcial to accelerate the graphitization process. The results show that, through appropriate composition design and technology, the C atom can quickly transform to grahite within 4 hours. The microstructure of the graphitized free cutting steel consists of ferrite, graphite and carbide. Moreover, the grain size of grapite is fine and the distribution is uniform, and the carbide mainly locate the ferrtie grain boundary or in the ferrite. In addition, the nuleation of graphite not only can take place on the second-pahse particles, but also spontaneous nuleation and growth.Key words: free cutting steel, hypoeutectoed steel, graphite, carbide, nucleation

The pre-processing method of blind source separation based on multifactor analysis is proposed to solve the blind source with noise. Firstly, the shortcomings of existing methods of blind source separation are point out after analyzing their principles. The multifactor analysis is introduced in blind source separation and the maximum likelihood estimate based on expectation maximum is used to estimate the common factor and random error. Finally the FastICA algorithm is used to separate BSS result. The validity and the advantage of this method are illustrated by an example.

Currently, the development of flood control system of Nanjing City has been entering a new critical phase, facing some great challenging problems that never experienced before. To meet these challenges, this research initially reviewed the developing process of flood control system of Nanjing City after China's reform and opening up. Based on the analysis of current flood control situation, four major challenge of was summarized. To solve these problems, this research provided some productive suggestions for future development of flood control system of Nanjing City from six perspectives, namely principle of flood control, layout of flood control system, drainage system improvement, flood management, technology application and supporting measures.

Additive Manufacturing (AM) is the digital manufacturing technology by which products are fabricated directly from computer models by selectively curing, depositing or consolidating materials in successive layers. The technology has provided an opportunity to rethink the methods of product design to maximize the product performance through the synthesis of material compositions, structure, and sizes. This overview is created to relate the unique capabilities of AM technologies and discuss the methods of product design. Finally, the current problems and difficulties in this field are discussed in this paper, and this paper proposes the development direction of the product design for additive manufacturing in the future.

The quantitative classification of transformer supervision can improve the quality of transformer supervision. For the contents of transformer supervision, this paper establishes an index system of transformer supervision. Example results show that the extension matter-element theory which is applied to transformer supervision quantitative evaluation is more reasonable. According to the categories of transformer supervision, this paper quantifies the uncertainty and builds the evaluation system of transformer supervision. It realizes the evaluation of transformer supervision and gets the key factors which influence the transformer supervision. This evaluation system is conducive to guide the transformer supervision to be more scientific and effective.

Making assessment of risk factors of power transformer life cycle cost modeling is an important mean of improving the scientificity of transformer life cycle cost management. Considering the risk factors of transformer life cycle cost, this paper presents risk assessment index system of transformer life cycle cost, applying matter-element model and extension analysis theory to quantify the qualitative indexes in order to assess the risk. Combined with an example, the paper quantifies the uncertain factors of power transformer life cycle cost management in order to build the life cycle cost risk assessment system. It realizes the risk rating of the transformer cost assessment, getting the key risk factors which affect transformer cost so that we can put forward targeted control strategies according to various risk factors in practical engineering.

The development of multi-core processors has provided a good solution to applications that require real-time processing and a large number of calculations. However, simply exploiting parallelism in software is hard to make full use of the hardware performance. This paper studies the parallel programming and optimization techniques on TMS320C6678 multicore digital signal processors. We firstly illustrate an implementation of a selected parallel image convolution algorithm by OpenMP. Then several optimization techniques such as compiler intrinsics, cache, DMA are used to further enhance the application performance and achieve a good execution time according to the test results.

To assure the safety of large power equipment during transportation, we developed the vibration model of large power equipment in transport process, derived the prediction model of allowed values of vibration before and during transportation. An online management and control system for large power equipment transportation with real time monitoring function was developed, in which the back-off algorithm based on warning priority was introduced in data transportation of wireless sensing network. The system changes the current offline recording of vibrations and other factors to online monitoring. Combined with prediction model, the system effectively prevents the damage of large power equipment during transportation.

Softwares is becoming increasingly important causes for failures of safety programmable electronic (PE) systems,PRA and CSRM both take it as an important risk contributor and respectively access risk of systems and software in system level.However they partly identify software-related risk scenarios ,and can’t tell what a software must do about all safety-critical conditions,i.e.,safety functions,especially warning functions for conditions software can’t control but must alarm operators to action immediately.Here we give a method to find all software-related safety-critical scenarios,through it all safety-critical conditions and the corresponding functions can be identified.

Aircraft noise is the chief source of the airport and its peripheral areas. CCAR imposes restriction on specific categories of aircraft and requires more strict measurements of the noise. More scientific measurement method is required to meet the progressively tighter certification standards. Test noise procedures for transport category and turbojet airplanes are analyzed in this paper. The main aspects involved are: test sit requirements, aircraft flight path guidance, aircraft position determination, take off tests, lateral tests and approach tests.

In this paper we use parallel computation to improve computer action detection and recognition system, use of VC programming control to realize parallel calculation algorithm, use Step 7 software to establish data interface of parallel communication, which realizes the data parallel exchange. Finally we design the computer system of human action recognition and optimization, and introduce the system into the design and development of free combat movement. In order to verify the effectiveness and stability of the system, we carry on debugging on the program, and obtain the test results curve of VC++ debugging. At the end of this paper, we use visual visualization function of VC program to achieve the visualization display of free combat movement. According to the visual display we can guide physical teaching. It provides a new computer method for research on free combat sports curriculum.

A FPEG (flexible piezoelectric generator) composed of PVDF (polyvinylidene fluoride) piezoelectric film, conducting resin and titanium alloy substrate, which occupies less room and produces electrical energy while the axial wind flows through the oscillator surface. When the axial wind flows through the generator surface, generator begins to vibrate and produce electrical energy, as the wind speed reaches a critical value, generator yields resonance phenomenon. In this paper, more work was placed on how the substrate structure parameters such as length, width and thickness affected the power generation capacity in resonance mode.

This paper investigates the interlaminar stress distributions of notched angle-ply thermoplastic laminate under tension numerically. The representative AS4/PEEK laminate with configuration of was studied by finite element code ANSYS. Computation results show: The interlaminar stress concentrations are evident and localized in the vicinity of the hole and the two free sides, and the maximum values always appear near the hole. Meanwhile, at interfaces of-45/+45 and +45/0, the concentration of peel stress is evident, while at interfaces of 90/-45 and 0/90, the concentration of shear stress is evident. Further analysis demonstrates interlaminar shearing stress is the dominating stress and may be the leading cause of laminate delamination.

The traditional method for detecting speech signal needs the help of microphone, which must be placed closely to the body of human beings. To some extent, this method would bring several inconveniences. Non-contact speech detection method breaks through the limitation of the traditional method, this new kind of speech obtaining method can detect speech signal quite well even in strong noisy background. However, this non-contact speech detecting system also produces some electromagnetic noise and circuit noise, which reduced the quality of radar speech signal. Therefore, based on the good time-frequency analyze performance, the lifting scheme was also proposed in this paper to remove noise from radar speech. Comparing to classical enhancement algorithm, such as spectral subtraction and Wiener filter, the proposed algorithm can remove the component of noise availably and reserve the original pure speech signal in a promising way.

The simulation of aging appearance is essential in the realistic modeling, We propose a method using existing aging image to simulate aging appearance, We establish the classification library, extract the texture feature of different types aging and save them, set the weight of the texture feature and synthesis texture according to the environment. In addition, user can specify the constrained texture mapping position optionally. This method can simulate various rusty phenomenon simultaneously. It can also be combined with physically-based method and ton spreading-based method to implement rendering of realistic 3D model rapidly.

A novel mutiscale and directionally adaptive image transform called contour based directionlet tansform is presented. Directionlet transform (DT) has shown its charming performance in image processing, but it has scrambled frequencies. Laplacian Pyramid is employed here to separate the low frequencies before applying DT for avoiding the drawback. And an adaptive threshold algorithm is proposed for denoising. Numerical experiments are performed to assess the applicability of the proposed method. The obtained results show that the proposed scheme outperforms Wavelet and Directionlet transforms in terms of numerical and perceptual quality.

Based on the velocity contrast of rocks, the seismic logging is to study the relationship of the velocity-depth by using the seismic wave data acquired in borehole. The concept of average velocity used in conventional method of seismic logging data may lead to a wrong interpretation. With help of the raytracing technique, This paper deals with the seismic logging data by Fast Reconstruction (FR) technique to obtain a fine velocity structure in borehole. The results from numerical modeling show that the method can be used in complicated structure with a fast computation and high accuracy.

Recently, to keep the network unblocked becomes more and more important, because that the urban traffic has the serious congestion. The model of network capacity is demonstrated with the concept unblocked reliability and reserve capacity. The simulation results shows that actual network capacity is less than its structural capacity constrained by the network control, which gives a new perspective for the future urban network planning.

The growing demand for accurate performance simulations of high-power Li-ion traction batteries requires a fast and effective method. In this paper, an advanced estimation model is proposed to evaluate Li-ion traction battery performance in pure electric vehicle (PEV) applications. The estimation model, which combines road load simulation and lumped parameter analysis, can predict vehicle traction power requirements and entire battery performance parameters both for charge (regenerative braking or grid charging) and discharge (traction power) processes. The model is validated for a battery pack in aPEVoperating over three representative driving cycles: (i) the new European driving cycle (NEDC), (ii) 60km/h constant speed driving cycle, and (iii) 30min maximum speed driving cycle. The results show that the combined performance model output corresponds well with measured data. Thus, this new proposed model can be used to validate battery pack performance during in-vehicle use with reasonable accuracy.

Based on analyzing the characteristics of engineering design enterprises, through investigating 30 Chinese design enterprises ,the present main engineering design service modes are summarized and analyzed, furthermore the backward management philosophy, lack of the efficient information feed back mechanism ,and no enough attention to the accumulation of knowledge are uncovered as the root causes of low innovation ability, the design defects, and extensive management in Chinese design enterprises. Under the great changes taking place in modern market environment, the Chinese engineering design enterprises are required to transform for complying with market demands and the world trend, so the life cycle design service mode is put up with the development strategies for the development of the engineering enterprises.

Model tests of the squeezed and branch pile with or without vertical load are carried out and the horizontal load bearing capacity are studied in this paper. Based on the model test results, the influence of vertical load to squeezed and branch pile horizontal load bearing capacity and the influence of horizontal load to squeezed and branch pile vertical bearing capacity are analyzed with FEM. The analysis results show that the vertical load may increase the lateral bearing capacity of pile, and the horizontal load may decrease the vertical settlement, but horizontal load may increase the horizontal displacement and moment of the pile body and lead to instability and cracking failure. This should be pay more attention in the practical engineering.

With the development of modern mechanics methods and computer technology, some practical commercial finite element analysis software was introduced to the ultrasonic cleaner design. ANSYS software is a financial structure, fluid, electric field, magnetic field, the sound field analysis in one large general-purpose finite element analysis software can be used in many industrial fields. The basic operation of ANSYS was introduced. The simulation based on the ANSYS was applied in the design of ultrasonic cleaner successfully, which can improve work efficiency and shorten development period of ultrasonic cleaner.

Analyzing the problem of the existed chaotic masking secure communication, given a new chaotic communication method with the separation between chaos synchronization control signal and chaos modulated signal. A chaotic pilot signal is used independently to synchronize the chaos of the communication transceiver, it is a better solution for the original chaotic communication systems in which the information signal is much smaller than the chaotic modulation signal and anti-noise performance is poor. The circuit simulation based on Sprott system I was built to verify the new method of chaotic communication. Simulation results show that it is more flexible to achieve synchronization between communication terminals, more accurate for chaos synchronization, high performance of anti-noise, and the strength of the information signal is no affected by the chaotic signal.

This study took mung bean sprout as test materials to measure the variation of gas concentration in the film over time. This study measured the permeability coefficient of the selected LDPE film under 8°C,13°C,18°C,23°C and 28°C and calculated the respiratory rate of mung bean sprout under temperature ranges from 8°C to 28°C by the method of Osmosis system using C language. The chemical kinetics model equation was fitted to the respiration rate of bean sprouts. Experimental results: 1. Permeability coefficient of film increased with the temperature, the relationship between the permeability coefficient of the film and the temperature fitted with the Arrhenius equation. 2. With the temperature increasing, the respiratory rate of mung bean sprouts increased. By fitting chemical kinetics equation of model to the respiration rate, the results showed that the variation of respiration rate conformed to the chemical kinetics equations. The relationship between temperature and the respiration rate constantkof the chemical kinetics equations were found following of Arrhenius equation.

Grape juice drinks processed from Muscat grapes as raw material was filled in glass bottle, PP plastic bottle and PE plastic bottle respectively after high temperature sterilizing. Original grape juice acted as control, and then all kinds of nutrients, color and aromatic substances were determined to evaluate the effect of different packaging materials on grape drink quality. The results showed that the content of total acid, reducing sugar and soluble solids of three packaging samples were decreased to some extent, and the color changed significantly. To be more specific, PP plastic packaging samples had the greatest nutrients loss and the most obvious color change. The sample packaging with glass had the most aroma types, the best preservation of the linalool and the maximum content of Terpenoids Chemicals compared to the other two packaging materials. Altogether, the glass was the best package materials compared with the other two materials.

In allusion to the system that there is but only severe time-varying and non-flexible coupling between the two hydraulic channels, the daul-cylinder hydraulic synchronous movement servo control system is designed for large die casting equipment, and its control model is establish. By guiding thought of self-learning control strategy, two levels of speed control scheme is adopted in the hydraulic system, namely the level adjustment and secondary servo compensation adjustment. On the basis, adaptive learning control scheme is established. Thus, its control strategy algorithm of incremental form is presented. Finally, through MATLAB(R2010a), the simulation analysis has been carried on to the system, the emulational results show that the control scheme can make the system to achieve excellent performances of synchronous movement.

The cascade development of river basin has important implication on the society, economy and ecological environment. To carry out optimal control and operation of hydro power stations can obtain a more significant overall efficiency, and provide basic support and guarantee to energy conservation and construction of ecological civilization. Taking into account the complexity and multi-objective property of operation of hydro power stations, as well as increasingly severe eco-environmental problems, this paper presents an optimal operation model of hydro power stations considering ecological environment water demand, and proposes an improved multi-objective immune genetic algorithm (MOIGA) to solve the model for better control of hydro power stations. This model is applied to the Xinan-Fuchun hydro power stations, and result shows that MOIGA is feasible for the control and optimal operation of hydro power stations.

In large continuous rolling process, that the roller can be accurately control have an important impact on production. In allusion to the characteristics of variable and nonlinear of hydraulic servo system parameters for controlling roller position, fuzzy PI control and adjusting the parameters in on-line are used, in order to realize the three cylinder synchronous control. The research results indicate: for system with external force disturbance, the fuzzy adaptive control has a strong anti-interference ability, and improve the robustness of the control system of multi-cylinder synchronization, as a result, to obtain the satisfactory control effect. To be carried out simulation with Matlab, the results show that the fuzzy PI control scheme is a high precision, efficient and feasible method, and can obtain the satisfactory results.

The grading speed limit programs were simulated under different traffic conditions by using traffic simulation software VISSIM, the applicability of grading speed limit programs in the highway construction work zone were studied, the value of each applicability assessment indicators was drawn, and the values were evaluated and compared comprehensively by a weighted addition ratings method. The results indicate that the degree of the applicability of each grading speed limit programs is different, and they have different impact on safety and traffic efficiency of highway construction work zone.

The Dempster-Shafer (D-S) evidence theory is an effective method for uncertain information fusion. Because multiple evidences from different sources of different importance or reliability in the reassembling fractured 3D objects are not equally important when they are combined. This paper presents a social cognitive optimization algorithm (SCO) to generate optimal evidence weight values based on historical training data. In the algorithm, a constrained nonlinear optimized model is established, which is solved by SCO. Compared with the two methods, optimization weight D-S proves more effective than the traditional D-S.

This research aimed to separate the signals of respiration and heartbeat effectively from the biological radar echo signals of vital signs detecting platform. Therefore the characteristics parameters of the respiration and heartbeat could be extracted to provide the basis for clinical diagnosis and disease prevention. This paper put forward a separation algorithm of heartbeat and respiration based on LMS adaptive harmonic cancellation, the combined harmonics of the breathing signal was regarded as a reference input signal of the adaptive filter to improve the algorithm. Related experiments were designed to conduct filter processing. Results show that the algorithm proposed proved to be more effective in the signals separation of respiration and heartbeat.

In view of the asymmetric reverse synchronization control problem of two hydraulic cylinders, several kinds of synchronous control scheme are put forward,that are total feedback and synchronization error correction,main/auxiliary control feedback and unilateral correction,respective feedback correction and total feedback and total correction.Through research and analysis, we reach the conclusion to make the system to achieve better dynamic and static performance, total feedback synchronization error correction or main/auxiliary control unilateral correction synchronous control scheme is better solution.

With the development of governing the Yellow River by the technology,it is inevitable to research the construction equipment to adapt to flood-prevention work. The cluthing and casting excavator for flood-prevention is produced under such kind of background. This equipment based on the working device of backhoe track hydraulic excavator was improved, the computer technology is introduced in the design of working device which can be for three-dimensional modeling,assembly and motion simulation analysis. The virtual design by Pro/E for the structural and motion of produces can short the design and manufacture time and cut down the cost, thus it can save the massive funds.The completive power of society is strengthen.

A new class of three-armed star-shaped liquid crystals 5a-5d were synthesized, they used 1,3,5-trihydroxybenzene as a core, ω-[4-(p-ethoxybenzoloxy) phenoxycarbonyalkyl acid (3a, 3b) and ω-[4-(p-nitrobenzoloxy) phenoxycarbonyalkyl acid (3c, 3d) as mesogenic arms. Their chemical structures were confirmed by FTIR and 1H NMR spectra. The mesomorphic properties and phase behavior were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and thermogravimetric analyzer (TG) measurements. The results showed that the three-armed star-shaped liquid crystals exhibited a broad range of liquid crystalline phases at moderate temperature. The mesogenic arm structures obviously affected the phase behavior. As the intermedius alkyl chain of the star-shaped compounds lengthened (from n=4 to n=8), their melting points decreased but mesomorphic temperature ranges increased. The temperatures when 5% weight loss occurred (td) were higher than 300°C, which revealed that the synthesized three-armed liquid crystals had a high thermal stability. Threadlike, droplet and schlieren texture, typical of nematic phase can be observed in the liquid crystalline state during heating or cooling process.

Recently, the amount of blogs on the Internet rises sharply. Hence, mining valuable information in blogs possesses realistic significance for improving user experience, network services, etc. This paper proposes a mining algorithm with blog authors' interests based on classification techniques, which introduces an evaluation standard of non-empty intersection. This algorithm can also improve the hit ratio of recommendation service based on blog authors' interests by means of the interest collection from expanding prediction; therefore, it can reach a higher degree of satisfaction. In addition, this paper performs experiments with the data set from Sina Blog and NetEase Blog, whose result illustrates the higher accuracy of our algorithm. Keywords: Blog mining; Interest mining; Classification algorithm; Non-empty intersection.

The media access control (MAC) protocol based on fixed slot allocation has low throughput and high delay in high load wireless mesh network. In order to improve the performance of wireless mesh network, we propose a scalable adaptive time division multiple access (TDMA) slot allocation algorithm based on the existing fixed TDMA. The algorithm uses the network structure of clustering and builds a more optimized frame structure, cluster head dynamically allocates time slot according to the packet number of the cluster member sent and the priority level, at the same time taking into account the situation of nodes joining and leaving to improve the scalability of the network The simulation results on OPNET network simulation platform show that the algorithm is superior to fixed TDMA algorithm in both throughput and delay.

The hydraulic control system of the dual-cylinder synchronous motion is designed, and the basic operating principle of the dual-cylinder synchronous motion system is discussed.The self-learning control algorithm of dual-cylinder synchronous motion is introduce, the synchronous control circuit is discussed .Dynamic simulation of dual-cylinder synchronous motion control system is presented, and factors affecting synchronous performance are analyzed.

A direct, efficient method for the problem of epipolar rectification in the uncalibrated casewas proposed. The method was based on minimizing a measure ofdistortion, by introducing anepipolar distance transform. The transform converted image intensity values to a relative locationinside a planar segment along the epipolar line, so it was robust to noises. The ratio of the distancesbetween two matching points in the epipolar lines was theoretically proved invariant to an affinetransformation for planar surfaces. To calculate the relative rotation between both cameras, thealgorithm was decomposed into three-steps to limit the distortion. Results show that the new measureis more appropriate for image rectification, and the three-step algorithm has obtained an accuracycomparable result both in estimation error and visual effect, especially when the initial epipolar linesare far from horizontal.

Top-and-seat angle connection is a type of semi-rigid connection, usually used in steel frame. The initial stiffness of top-and-seat angle connection is an important index for steel frame design. The article studied the initial stiffness of the connection considering the influence of column flange. The deformation and mechanical characteristics of top-and-seat angle connection were analyzed using ANSYS. According to the results of FEM analysis, theoretical models of the connection and the initial stiffness formula of connection were proposed. For verifying the correction of the formula, 8 FEM models were built and initial stiffnesses were calculated correspondingly. The formula proposed by the article agreed well with the results of the FEM analysis. And it proves that, the initial stiffness formula of top-and-seat angle connection proposed herein can be used in the design.

To improve the global convergence speed of classical social cognitive optimization (SCO) algorithm, a novel hybrid social cognitive optimization algorithm based on quantum behavior (QSCO) is proposed. In the proposed algorithm, learning agents learn in a quantum multi-dimensional space and establish a quantum delta potential well model. A quantum search process is incorporated into local searching operation so as to enhance the local searching efficiency in the neighboring areas of the feasible solutions. Simulation results on a set of benchmark problems show that the proposed algorithm has high optimization efficiency and good global performance.

In this paper, we present a new nonlinear ternary interpolatory subdivision scheme which has the properties of convexity-preserving, circle-preserving and the limit curve iscontinuous. In each subdivision step, the newly generating points will be on the circle determined by the interpolatory point and its adjacent points. Numerical examples show that this algorithm is simple and curves generated by this subdivision scheme are fair curves.