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Because the deterioration rate of bridge decks is higher than that of other bridge components, intermittent replacement of bridge decks stands to be a viable approach to extending bridge service life without replacing entire bridge components. A lack of understanding of the effects of concrete removal on the horizontal shear capacity of existing shear connectors led to a question being raised about the necessity of removing all of the concrete during a deck replacement. The purpose of this study is to investigate the influence of the remaining concrete around the shear connectors on the horizontal shear capacity of the shear connection. An experimental program consisting of push-out testing was implemented. Twenty-seven small-scale specimens were fabricated using three different concrete removal levels (50%, 75%, and 100% concrete removal) and three types of shear connectors (shear stud, channel, and angle plus bar). Push-out testing was conducted for all the fabricated specimens until the specime...

Nine simply supported circular steel concrete-filled tubes (CFTs), two circular steel posttensioned concrete-filled tubes (PTCFTs), and one circular steel fiber–reinforced concrete-filled tube (FRCFT) have been tested in an instrumented drop-weight impact facility. The weight and the height of the drop-weight were varied to cause failure in some test specimens. The failure modes and local damages in those specimens have been investigated extensively. Failure in the steel tubes was commonly tensile facture or rupture along the circumference. Concrete core in the impact area commonly crushed under compression and cracked under tension. The use of prestressing strands and steel fibers significantly restrained the concrete tension cracks in the PTCFT and FRCFT specimens, respectively. The experimental results are analyzed in the context of principles of energy and momentum conservation.

Concrete-filled circular steel tubes (CFT) have recently gained significant attention for their enhanced strength and ductility over the conventional steel and reinforced concrete construction. The concrete compressive strength is significantly increased by the lateral confinement provided by the steel tube and local buckling of the steel tube is restrained by the concrete infill. This paper investigates the further enhancement of these composite actions due to post-tensioning the concrete cores inside circular steel tubes. The flexural behavior of a post-tensioned CFT as well as a non-post-tensioned CFT was studied experimentally and analytically. A numerical algorithm for predicting the moment capacities of circular CFT, with or without the post-tensioning effects, has been validated against the test results by the authors as well as those published in the literature.

The properties of the self-similar parabolic pulses interaction in a dispersion-decreasing optical fiber with normal group-velocity dispersion are firstly investigated in our paper. We find that two parabolic pulses separated by a time-delay create oscillation with a sinusoidal fit at the beginning of their overlap, and then further evolve into a train of asymptotic dark solitons. Additionally, outside the overlap regime, the evolution is equal to a single pulse’ propagating behavior. The chirp after interaction in the parabolic pulses still allows for efficient and high-quality pulse compression.

With the development of multimedia computer technology , interactive projection is becoming an interactive display system and entertainment in people's daily life.Interactive projector based on actual needs, design gesture based feature extraction algorithm Hu moments, identified by SVM classification shot type, and ultimately through experiments verify the effectiveness and practicality of the system.

This paper discusses the calculation problems of bending deformation of FWP processing. Take three axis CNC machining as an example, to establish mechanics model of flexible workpiece processing process. The flexible workpiece balance equation is a two-dimensional partial differential equation, to solve the problem of flexible workpiece bending deformation using Rayleigh-Ritz method and designing the test function of bending deformation of flexible workpiece. By satisfying the minimum potential energy condition of FWP processing to work out the approximate solution of bending deformation of flexible workpiece, find out the relationship between material properties of flexible piece, acting forceFz, and deformation value. Finally, the rectangle flexible workpiece which is made up of polyurethane sponge is selected as an experiment subject. The results show that the average relative deviation between theoretical value and observed value is only 5.51%. It is proved that the bending deformation test function satisfies the actual deformation calculation requirements.

In this paper, one experiment teaching case design for photoelectric sensor signal processing is proposed, by using the filtering of contact image sensor (CIS) as a example. The signal with the noise of CIS the scanning output signal will affect the authenticity of the image, so based on the analysis of the CIS output signal noise, the design of two-dimensional wavelet transform for the reconstruction of the image by the CIS output signal of the filter which is based on Xilinx FPGA dsp48 structurally and realized the accelerated calculation through the FIR IPCore, will be introduced in this paper. From the experiment, this algorithm can reduce most of the noise in reconstructed image to ensure reconstructed image can be complete and clear.

A good photoelectric experimental teaching platform plays a very important role in the course of sensor, photoelectric engineering and photoelectric detection. With the development of information technology, it adds more and more new function for photoelectric teaching platform, which will bring great convenience to teaching undoubtedly. In view of this situation, in order to achieve a better teaching effect, the design of multi-function photoelectric teaching experimental platform will be put forward in this paper by taking the ARM as basic module, designing a new type of photoelectric teaching experimental platform with voice recognition and touch screen. Keyword-Photoelectric detection; Photoelectric experimental teaching platform; Touch screen

Infrastructures and key members are potentially exposed to accidental loads due to extreme situations such as collisions, impacts, and terrorist bombings. Consequently, the current design concept requires that the structures or key members possess adequate capacities to resist accidental loads. To understand the mechanical response of concrete-filled steel tube (CFT) beams subjected to impact loads, this paper presents numerical simulations on the CFT beam tests in an instrumented drop-weight impact facility using finite element code LS-DYNA. The adequacy of finite element modeling (FEM) has been validated against drop-hammer impact tests in the literature. Based on the dynamic increase factors (DIFs) derived from FEM, an algorithm based on theoretical sectional analysis (TSA) is introduced to evaluate the dynamic plastic moment capacity of CFT beams. A linear relationship between initial impact energies and absorbed energies by CFT beams is found using either FEM or TSA. To assist engineers in designing simply supported circular CFT beams subjected to lateral impact, an energy design procedure using TSA is proposed, along with the ranges of key parameters, and an example is presented to illustrate the design procedure.

Innovation and entrepreneurship for college students cultivate a new era of higher education is an important content, technology innovation and entrepreneurship competition is the main vehicle for capacity building and platforms. Universities to carry out scientific and technological competition can stimulate innovation and entrepreneurial potential college students, the majority of young students to cultivate innovation and entrepreneurship skills and teamwork spirit, improve the quality of students' scientific and technological innovation, scientific and cultural prosperity of the campus, and to promote research with the close integration between, can play positive role in promoting, is to train high-level, high-quality, all-round development of innovative talents and effective way.

Deformation decisions knowledge extraction based on RS and entropy reduction is proposed for FWP processing which processing deformation factors is complex and difficult to extract. Decision table of processing deformation which takes FWP processing deformation factors as conditional attribute and processing deformation level as decision attribute. Changes in the level of mutual information as a condition attribute importance to the decision attribute evaluation, when the greater the change in the conditions the more important attribute for decision attribute. In Application examples, there are 13 conditional attribute in decision table, in accordance with Pawlak reduction methods and genetic reduction algorithm to extract 5 highest impact factors, 4 highest impact factors for FWP processing deformation decision are extracted using entropy reduction method. Prediction error of Entropy Reduction Method is 32.58% less than Pawlak’s reduction method, and 21.45% less than Genetic reduction algorithm.

Data migration refers to the process of moving the data from one database environment to another. This article describes the general methods and procedures of the data migration between heterogeneous databases and the implementation of data migration from Oracle to MySQL. It also analyzes the causes of heterogeneity between different databases, the principle of data migration and establishes a general model of heterogeneous data migration platform.

In this paper we prove that the Berezin transform is of type of weak (1,1) and bounded on the Orlicz space L φ(D,dA) if its Young function φ satisfies the -condition. Also we show that the dual of the Bergman space is the Besov space and its predual is the little Besov space if the Young function φ satisfies the Δ2-condition (here φ and ψ are a pair of complementary Young functions).

In this paper, we experiment the capabilities of continuous density Hidden Markov Model (CHMM) to model the offline diagram sketch signals such as the electrical circuit diagram and the flowchart diagram . We attempt to imitate the online signals by extracting the offline diagram data as the time-varying coordinate sequence based on the Gradient Sharpening and Freeman code, considering that is generated by a two-level stochastic process. The underlying process governs the stroke production from a neuron-motor control point of view: go straight line, change direction line, produce a curve. A second stochastic process delivers the continuous density observed signal, which is the sequence of offline extracted points. A stroke segmentation technique based on CHMM architecture and geometric features is proposed. On a dataset of 180 hand-drawn sketches, the proposed method allows to classify correctly more than 90% of the points with respect to the connector and symbol classes.

A method of measuring the two-dimension and nano-width of wafer with fast speed and high precision level of sub-pixel width is offered in this paper. This method takes two steps: Firstly, utilizing the standard ruler to fast measure the pending size with per-pixel level of precision; secondly, utilizing the technology of spatial moment pixel subdivision to precisely locate the edge pixels of pending graph, achieving sub-pixel level of precision. We apply this method to measure and validate one welding-plate among the wafers. The result indicates that the measuring precision has been improved significantly and it can satisfy the requirement of the wafer's CD measurement and calibration.

The defect exhibited a great variety of kinds have a direct impact in the yield of IC wafer in the lithography process. The missing material defect is an important factor of reducing the yield of IC, it mainly causes circuits to be disconnection failure, so it is important to recognize the missing material defect and ascertain the circuit's failure style. In this paper, a recognition method for disconnection failure of the missing material defect based on skeleton character is presented. The thinning algorithm is used to extract the skeleton of image. The principle of deleting redundant points and branches is introduced to get the skeleton of single pixel and single direction. Then, the method of neighborhood field tracking is used to recognizing the disconnection circuits.

The singular integral equations with Cauchy kernels a ( t ) φ ( t ) + b ( t ) x i ∫ Γ φ ( τ ) τ - t d τ + ( T φ ) ( t ) = f ( t ) have studied in Lp(Γ), ∀p >l, in detail. Here Γ stands for the set of a finite number of closed Liapunoff's curves which have no common points and T denotes the completely continuous operator in the space sunder consideration. In this paper, we consider the equations mentioned above in Orlicz spaces LMcr). It is proved that the N6ether theorem and the index formula are hold true in the case of reflexive Orlicz spaces.