最新刊期
卷 39 ， 期 4 ， 2007
- 摘要：Abstract:A new kind of FRP screw anchor has been trial produced, which can be turned into soil to a designed length with less disturbance and its rod is flexible and not prone to corrosion. The application of FRP screw anchor, geogrid and geofoam slab in repairing of canal slope of expansive soils has been introduced in this paper. The geofoam slab was used to reduce the expansive force under the concrete slab. The geogrid improved the factor of safety against complete sliding surface. And the FRP screw anchor was designed to anchor the concrete frame girder above the berm and concrete slab below the berm. The paper presents a design method and a monitoring plan for this project. The technical and economical comparisons with other schemes such as non swelling soil replacement method, anti-slide pile and reinforcement of geogrid in layers prove that this scheme has remarkable advantages.关键词：FRP;screw anchor;geofoam;geogrid;repair;canal slope;expansive soil
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发布时间：2023-11-28 - 摘要：Abstract:In order to mitigate the loss of live and property in a municipal region due to a dyke break or dam break or extremely large flood, it is very important to accurately simulate the movements and distributions of flood in both the temporal and the spatial domains. However, irregular structures and complex inner and outer boundaries within a municipal region can make the simulation complicated. Therefore, a 2D FVM flood simulation model based on arbitrary polygonal mesh system to discretize the 2D shallow water equations is proposed. The numerical simulation model is validated through its application in the Fuji River basin of the central Japan. Results indicate that the simulation model is stable, accurate and easy to capture the properties of flooding waves, and that the model is also suitable for the assessment of flood risks and losses in municipal regions,for the development of hazard maps, flood warning systems and emergency plans.关键词：shallow water equations;flood;inundated area;inundated waterdepth
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发布时间：2023-11-28 - 摘要：Abstract:sing wavelet transform, the characteristics of periodicity SMP time series have been probed. According to the characteristics of SMP, this paper presents combined forecast method based on wavelet transform. The non stationary time series of SMP is decompo sed into several detailed stationary time series and a smoothed non stationary time series according to the principle of wavelet decomposition. The stationary time series is simulated by using AR(p) method and the non stationary series is simulated by using artificial neural network model. The comparison shows that the error of the simulation adopting this method is smaller than that by using auto-regressive method.关键词：SMP;forecast;wavelet transform;ANN
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发布时间：2023-11-28 - 摘要：Abstract:High pressure hydraulic pulse is effective to deal with some engineering problems such as hydraulic breaking rock and cutting metals. This paper advances a novel rotary ball pulsing nozzle based on whistle principle in daily life. The mechanism of pulse activated by this novel rotary ball pulsing nozzle is pretty complex. In order to check up its effect, a high-pressure pump with 50 m3/s flow is used to experiment on the pulsing nozzle, and the results are compared with the high pressure efflux produced by general nozzles. Experiment indicates that the novel rotary ball pulsing nozzle can produce high frequency pulse, while the efflux produced by general nozzles is common turbulent flow with no obvious pulse; the fluctuating pressure produced by this novel rotary ball pulsing nozzle is far higher than the high pressure efflux by general nozzle, thus it is in favor of breaking rocks or metals. The experimental study has considerable reference value in engineering design.关键词：hydraulic pulse;nozzle;hydraulic breaking rock;jet;pulse pressure
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发布时间：2023-11-28 - 摘要：Abstract:Experiments are carried out for the evolution of the hydraulic characteristics of the flow in the flip bucket and the scour downstream river. Measures are progressed for analyzing the feature of hydraulic characteristics and scour. Basic problems are evaluated with original design shape of flip bucket. Experimental data are obtained in different geometry of flip bucket and the general characteristics of the nappe and the scour are analyzed. On the base of experimental investigation, an optimum geometry is provided for the shape of flip bucket with the elliptic curve floor. These researches can be of help for the design in practical project and can be adopted by other projects.关键词：tunnel;jumping nappe;flip bucket optimum;elliptic curve floor
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发布时间：2023-11-28 - 摘要：Abstract:A formula of Froude number at the section of starting flare is deduced in this paper.It is shown that the relationship exists among the location of the flaring gate piers,the Froude number at the section of starting flare,the weir head, the head loss and the gate width.Collection of several local water plants’data is carried out and the Froude numbers are calculated by the formula.The result shows that these Froude numbers distributes between 1.7~2.3 and the average value is 2.042. Based on actual projects, the influence of the flaring gate piers location to the Froude number is discussed. The calculated results agree well with those of the numerical stimulations.关键词：hydraulic structures;flaring gate pier;Froude number at the section of starting flare;the weir head
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发布时间：2023-11-28 - 摘要：Abstract:In order to design an arch structure with good nonlinear dynamic characteristics, the nonlinear dynamic behaviors under a long time external force have to be investigated. The chaotic behaviors of the parabolic elastic arch with two hinge supports subjected to a transverse distributed varying periodic excitation are investigated in this paper. Based on the geometric equation of deformable body and the equilibrium equations of an arch element, the nonlinear dynamic model which dominates the transverse vibration of the elastic arch is established first,and then the nonlinear differential dynamic system is obtained by using Galerkin’s method, thus the fixed points and the homoclinic orbits are found out. The critical condition of chaotic vibration of the elastic arch is obtained through the Melnikov's method. Finally the dynamic characteristics (such as Lyapunov exponents and Lyapunov dimension and the phase trajectories and also the Poincare map etc.) which can be used to explain the dynamic behaviors of the differential dynamic system of the elastic arch are calculated by using numerical simulation for different parameters. It is found that the motion of the parabolic elastic arch with two hinge supports subjected to a transverse periodic excitation may be stationary or chaotic motion. The stationary motion occurs if the amplitude of the transverse periodic excitation is small, but the chaotic motion occurs if the amplitude is large.关键词：elastic arch;Melnikov function;chaos;differential dynamic system
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发布时间：2023-11-28 - 摘要：Abstract:Per Bak，the introducer of Self-organized Criticality, thought that power-law distribution was the evidence for Self organized Criticality, and the non-characteristic scale phenomenon which was presented in extended dissipative power systems in the self-organized critical state. Per Bak’s theoretical evidence was the sand pile model in the self-organized critical state. So the real sand pile experiment and sand pile experiment simulated by computer have been carried out in our research. It can be put forward that many small scale avalanches take place in the sub critical state in sand pile，and the closer to the critical state, the stronger the system fluctuates, then large-scale avalanches emerge now and then. So the occurrence of the large scale avalanches is less often than the small scale avalanches when sub-critical state approaches to the critical state. The scale of avalanches presents power-law distribution. This kind of situation is regarded to be more universal than former theories from Per Bak.关键词：power law distribution;sand pile model;Self-organized Criticality
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发布时间：2023-11-28 - 摘要：Abstract:It needed do a lot of computation in order to study the self-organized critical of large-scale sandpile. Parallel programming was introduced to overcome the shortcoming that serial program wastes a great deal of time. The parallel algorithm of sandpile model was realized by using master-slave mode through message passing interface (MPI) and C. The simulation result showed that the advantage of parallel computation couldn’t exhibit when model scale was small. The parallel computation time would shorten and got good acceleration ratio when model scale was larger than 200.The application of parallel technique to two-dimension sandpile model usually shortens computation time and increases efficiency. It would provide experience to study whether self-organized critical had scale effect further .关键词：cellular automata;sand pile model;self-organized critical;parallel computation;MPI
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发布时间：2023-11-28 - 摘要：Abstract:To investigate the biomechanical effects of intersegmental stability due to laminectomy, a three dimensional nonlinear intact C2-C7 FE model was developed. Then the modified FE model was set up to simulate laminectomy for intersegmental stability analysis. The inferior surface of C7 vertebra was constrained in all directions as boundary condition. Pure moment of 1.5 Nm was applied over the top surface of C2 vertebra to simulate the movements of cervical spine under flexion, extension, lateral bending and axial rotation respectively. Results showed that there are apparent effects on intersegmental stability of cervical spine models due to one, two and three level laminectomy. A conclusion can be drawn that the intersegmental stability under all loading models(flexion extension, later bending, axial rotation) due to surgical procedure must be considered to making a biomechanical evaluation on multilevel laminectomy.关键词：cervical spine;laminectomy;intersegmental stability;finite element method
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发布时间：2023-11-28 - 摘要：Abstract:A shaking table test of 1/15 scale model of a high rise building was carried out in the Shaking Table Division of State Key Laboratory for Disaster Reduction in Civil Engineering at Tongji University. The model’s dynamic characteristics and responses of acceleration, deformation, strain and torsion under different level earthquake were investigated. Then the seismic response of the prototype structure were deduced and analyzed. The dynamic behavior, failure mechanism and the cracking pattern of the prototype structure was studied. The test and analytical results show that the periods of the first three modes of the prototype are 1.975 seconds(Y translation), 1.72 seconds(X translation) and 1.423 seconds (rotation) in turn, thus the ratio of the period of the first rotation mode to the first translation mode is 0.79. The maximum story drift angle of the prototype structure under frequent and rare earthquake is 1/798 and 1/163 respectively, which meet the earthquake resistance requirement. But the torsion of the prototype structure does not satisfy the codes specification. Finally, some suggestions for the engineering design of the structure are put forward.关键词：high rise building;model test;shaking table test;dynamic characteristics;seismic response
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发布时间：2023-11-28 - 摘要：Abstract:In order to overcome the problems on numerical simulation of structures with thin coating layers on its surfaces,a three dimensional analytical solution was presented for free and forced vibrations of simply supported rectangular thick plates with thick orthotropic coating layers on the top and bottom surfaces. In the absence of body forces, the elastic dynamic equations of the coated plate the constitutive description of the anisotropic coating layers, and the isotropic plate were given first.Then the suitable displacement functions that identically satisfy boundary conditions on the top and the bottom surface and the interface conditions between the plate and the coating layers were used to reduce equations to a set of coupled ordinary differential equations, which were then solved by the power series method. Finally by the comparison of the analytical natural frequencies, displacements and stresses of a rectangular coated plate applied a sinusoidal spatial pressure on its top surface with those given by the finite element method (FEM), the validity of the analytical solution given in this paper is testified关键词：orthotropic coating layer;rectangular plate;vibration
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发布时间：2023-11-28 - 摘要：Abstract:The flue gas desulfurization with pyrolusite pulp can produce the byproduct of manganese sulfate from the corresponding chemical reaction between MnO2 in pyrolusite and SO2 in flue gas, and moreover, Jet bubbling reactor（JBR）is the reactor that fits this technique very well. However, it is difficult to achieve the goal to obtain high enough SO2 absorption efficiency and Mn2+ extraction rate simultaneously in a single JBR. Thereafter, some research work about the effect of additive percentage of pH value buffer solution and oxygen concentration in flue gas on this system of flue gas desulfurization with pyrolusite pulp in a single JBR was carried out, and it was illustrated that the optimized additive percentage of pH value buffer was 30% and 10% when oxygen concentration in flue gas is 21% and 7% respectively. Based on the experiment results, it was proved that under the conditions of simulated flue gas from real flaming coal, if the additive percentage of pH buffer value was 10%, the SO2 absorption efficiency and Mn2+ extraction rate could both reach above 80% in a single JBR. Wherefore, it could be concluded that this technique of flue gas desulfurization is not only operationally but also commercially feasible, and also, promising in industrial application in the future.关键词：pyrolusite pulp;flue gas desulfurization;pH value buffer;oxygen concentration of flue gas
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发布时间：2023-11-28 - 摘要：Abstract:To obtain recombinant human insulin(rhI), (His)6-Arg-Arg-human proinsulin (RRhPI) was expressed by Escherichia coli(E.coli). In the optimum medium of 5 g/L tryptone，2 g/L glutamic acid，7 g/L yeast extract，0.5 g/L ammonium sulfate，2.5 g/L glucose，2.7 g/L glycerol,100 mg/L ampicillin,50 mg/L kanamycin，and pH 7.2, and with the addition of 0.5 mmol/L IPTG at intermediate exponential phase and induction for 4 h , 51.2 g wet E.coli and 16.2 g inclusion body were harvested from 1 L medium in fermenter. The results showed that certain concentration of β-mercaptoethanol in inclusion body solution and oxidized glutathione in refolding solution were helpful to RRhPI refolding. With the well optimized technology, 74 mg rhI was obtained from 1 L culture medium.关键词：(His)6-Arg-Arg-human proinsulin;recombinant human insulin;E.coli
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发布时间：2023-11-28 - 摘要：Abstract:Water soluble fluorocopolymers composed of 2,2,3,3-tetrafluoropropyl methacrylate (TFPMA) and methacrylic acid, and water soluble methacrylate copolymers composed of butyl methacrylate and methacrylic acid were synthesized by solution polymerization. Photopolymers for holographic recording with these copolymers as the binders were prepared and studied in terms of photosensitivity, reflective efficiency and space resolution. The experiment data in comparison indicate that the photosensitivity of the photopolymers containing TFPMA was lower and the reflection efficiency were increased when recording at lower frequency, but decreased at higher frequency. The change of F/O atomic ratio on the fluoro photopolymer surface, as determined by XPS, indicated that oxygen in air participated in the photopolymerization in photorecording. The differences of reflective indices caused by the laser initiated photopolymerization are not the only factors affecting the holographic recording. Compatibility among the components in the final material is also important.关键词：fluoro-containing copolymer;photopolymer;holographic recording;reflective efficiency
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发布时间：2023-11-28 - 摘要：Abstract:In order to describe quantitatively the fatigue characteristic of the alloy Zr-4’s low-cycle fatigue fracture (Zircaloy-4), based on wavelet decomposition technology, the change of fracture energy in 3D space and the effect of sample state and loading direction to fatigue life were studied. The obvious stages of energy curve were discovered along the crack expanding direction in the propagation zone. There were large changes in the 3D appearance of fatigue fracture along the crack expanding direction. The most roughness segment is in the primary stage, and then the 3D appearance of fatigue fracture was becoming smoother. The energy of crack was far larger than that of the ambient body in vertical direction of the crack propagation. It was showed that the 3D appearance of crack is steeper than that of ambient areas. The energy curve of hydrogenation is above the curve of hydrogen free in the same loading direction. Therefore, hydrogen can improve the fatigue characteristic of Zircaloy-4. According to energy curve, low cycle fatigue life of R sample is larger than that of T sample. However, the result of experiment isn’t coincident. It showed that there is a definite localization to differentiate the fracture life only using energy curve.关键词：Zircaloy-4;energy curve;hydrogenation;loading direction
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发布时间：2023-11-28 - 摘要：Abstract:The stacking fault probability and damping capacity of Fe-19Mn,Fe-17Mn-2Cr and Fe-19Mn-1.5Si alloys were studied. The damping capacity was measured using reversal torsion pendulum. The stacking fault probability and volume fraction of ε-martensite were determined using XRD. The result indicated that the damping capacity of three alloys increases almost linearly with the increasing of strain amplitude. This can be explained using the breakaway model of Shockley partial dislocations. Si increases the stacking fault probability and the number of Shockley partial dislocations of Fe-Mn alloy, but decreases the damping capacity because it introduces much distortions of lattice which pin the moving of Shcokley partial dislocations. Cr also decreases the damping capacity of Fe-Mn alloy, but its effect is not heavier than Si because the distortion of lattice after adding Cr is not more serious than adding Si.关键词：damping alloy;damping capacity;Fe-Mn;Shockley partial dislocation;stacking fault probability
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发布时间：2023-11-28 - 摘要：Abstract:Forming a low resistance contact to CdTe thin films is a key issue for successful improvement of the performance of CdTe solar cells. The CdTe thin films were etched with nitric-acetic (NA) acid and a Cu back contact layer was deposited onto the etched CdTe surface, then the CdTe solar cells were fabricated. The results indicated that the nitric acetic acid pretreatment forms a highly conductive Te layer on the back surface of the CdTe thin films and it is an isotropic etching. An efficiency of 11.75% for CdTe solar cells was obtained when the back contact layer was annealed under optimum conditions.关键词：etch;back contact;CdTe solar cells
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发布时间：2023-11-28 - 摘要：Abstract:In order to rule the users’ behaviors in an intranet and prevent them from using the intranet resources maliciously to destroy the order of the communication or steal the sensitive information, deregulation operation of the subject in an intranet was analyzed, and an intranet monitor system was designed and implemented by real time monitoring usage resources of terminal in an intranet. The prototype system’s module structure and the application in practice environment were specified, and the key technique adopted in the system was specially analyzed. The practical application showed that the monitor system could monitor usage resources of terminal and control operation of the object.关键词：intranet;terminal resources;API HOOK;DDK;reverse connection
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发布时间：2023-11-28 - 摘要：Abstract:Traditional Multiobjective Optimization Algorithms are inefficiency in high dimensional decision space. To solve this problem, a novel method named Multiobjective Optimization based on Gene Expression Programming (GEPMO) was proposed. The main contributions of this study include: proposing a new coding method for chromosome,designing some operators for the new coding,analyzing the size of coding space, and presenting the framework of GEPMO. Extensive experiment results on enhanced standard test functions showed that, GEPMO is feasible and effective. In high dimensional decision space，the result set of SPEA is covered by GEPMO at least 87.5%, inversely at most 5%.关键词：multiobjective optimization;Evolutionary Algorithm;high dimension;gene expression programming
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发布时间：2023-11-28 - 摘要：Abstract:In order to implement a reliable data sync sub system based on IP network and provide transparent mirror storage for up level applications, an IP based remote data sync method was presented. This method simulated a SCSI disk device which supports standard SCSI disk device instructions. The SCSI disk device was composed of two disks, one is the native disk in the local server and the other is the remote disk in the remote server. When a writing operation is issued to the SCSI disk device, the data is written to the native disk, and at the same time, the data is sent to the remote server, where the same writing operation is performed to the remote disk. This method provided real time data sync without affecting the business continuity of working systems, supported inexpensive two site storage and enhanced the reliability of the application system.关键词：IP network;data sync;storage;fault tolerance
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发布时间：2023-11-28 - 摘要：Abstract:A concept of dependence evaluation function and MMDE (Multidimensional Medicine Dependence Evaluation) algorithm were proposed to determine the dependence relationship of multidimensional medicines aiming at mining the compatibility law of multidimensional medicines. The difference function was used to determine the divergence degree of the distribution of medicines, and a new method based on the modified difference function was proposed to compute the dosage of imperfect medicines based on the modified difference function. Experiments showed that the new method for mining the dependence relationship of medicines has accuracy greater than 80%.关键词：data mining;compatibility law;dependence evaluation;difference function
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发布时间：2023-11-28 - 摘要：Abstract:To test the reachability of the program statements, it is necessary to find out test cases that can result in corresponding control flow path execution. It is equivalent to the resolving of Path Constraint-Satisfaction-Problems, and the resolution is the test cases that can meet the reachability-testing requirement. Based on Forward Checking Algorithm, R_BinSearchFC algorithm was proposed for better searching performance. Boundary test data selecting technique and binary tree searching method were employed in the algorithm for real type data set computation and the resolution time could be efficiently reduced. Experiment results showed good effect for automatic testing statement reachability.关键词：automatic software testing;constraint satisfaction problems;forward checking;heuristic study
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发布时间：2023-11-28 - 摘要：Abstract:Fast and accurately extracting the centre line of light stripe of image is one of the most important problems of 3D measurement based on line-structure light. A new centre extracted method that combined the alterable direction template with barycenter method was proposed for the implementation of real-time image processing. First, the threshold of laser stripe was computed by the host computer and laser stripe was determined in real time by the neighbor attribute of grey level of pixel. Second, the sketch was obtained by thinning the light of stripe and pruning the branch. Third, the normal direction of the point on the sketch line was computed by using the alterable direction template. Finally, the centre-line of light was detected by using barycenter method. It has been proved by examination that this method can efficiently extracted the centre-line of light stripe.关键词：3D measurement;line-structure light;direction template;barycenter method
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发布时间：2023-11-28 - 摘要：Abstract:HHT(Hilbert Huang Transform) is a new and self adaptable time serials analysis method based on mode decomposition. Heart sound signal (HSS) is a typical non stationary signal, and it is difficult to be processed by traditional signal processing methods. In order to have deep insight of the heart dynamic characteristics, HHT algorithm was applied to analyze the HSS. Firstly, an improved HHT algorithm was proposed; then, the feasibility of the improved algorithm on a non stationary simulated signal was tested; finally, the algorithm was applied to analyze a healthy HSS. The result showed that the algorithm can efficiently decompose the HSS into IMFs with different time scales, which corresponding to different intrinsic characteristics of the signal. The energy distribution can be clearly shown in the Frequency-Energy spectrum. It was concluded that the improved HHT algorithm is available to analysis HSS.关键词：HHT(Hilbert-Huang Transform);EMD(Empirical Mode Decomposition);IMF (Intrinsic Mode Function);HSS(Heart Sound Signal);Hilbert Spectrum
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发布时间：2023-11-28 - 摘要：Abstract:Knowledge plays a key role in knowledge management, while no adequate attention has been paid on how to construct knowledge repository by means of the existing resource. On the basis of analysis multiplex characteristics of process knowledge of complex product under collaborative design between enterprises, a representation and building method of domain ontology and service ontology is proposed for process knowledge of complex product in the semantic environment. Structure architecture is presented to build process knowledge ontology by protégé modeling tool, and process knowledge is formalize described based on description logic language OWL. As the association among different ontologies in the semantic hierarchy, the similar and relative degree among product process ontology concept was analyzed in semantic evaluation method, then an ontology concept set of relationship measurement was designed. According to these methods, many meaningful tasks of searching and clustering of process knowledge under semanteme ontology description were achieved, and so effective integration and sharing among process resources were guaranteed as a result.关键词：process knowledge;ontology;ontology measurement
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发布时间：2023-11-28
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