最新刊期
卷 45 ， 期 6 ， 2013
- 摘要：Abstract:Orthomorphism plays an important role in the design of symmetric cryptography. To analyze its construction, counting and properties further, a problem in a conclusion about linear orthomorphism was pointed out and corrected. Then, with the corrected conclusion, a non-redundant construction method to generate all maximal linear orthomorphisms was presented, while the previous method would produce repeatable results. The number of orthomorphism was proved to be a multiple of 2 to the power (n+1) based on the relationship between affine orthomorphism and complementary permutation. At last, a definition of algebraic immunity was proposed and proved to be CCZ-equivalence-invariant. The algebraic immunity of a non-affine orthomorphism was also proved to be equal to that of complementary permutation of this orthomorphism.Same is the case with some other cryptographic properties,such as difference uniformity, nonlinearity and algebraic degree.
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发布时间：2023-11-14 - 摘要：Abstract:A 3-dimensional meet-in-the-middle (3D-MITM) attack on block cipher KTANTAN32 was proposed, which divided the algorithm to three segments by guessing two certain intermediate states and applied meet-in-the-middle attack on each segment respectively.This attack worked with a time complexity 267.63in terms of full round encryptions and used only 3 plaintext/ciphertext pairs. Furthermore, KTANTAN32 could be broken with a time complexity of 265.17 if combining 3D-MITM attack with data preprocessing and caching techniques, which avoided the repetition calculation. The results provided a general method for analyzing the security of other block ciphers by 3D-MITM attack.关键词：cryptanalysis;meet-in-the-middle;block cipher;KTANTAN;splice-and-cut;indirect partial matching
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发布时间：2023-11-14 - 摘要：Abstract:To solve problems of trust evaluation for a commodity without rating or few ratings in e-commerce system, a trust bootstrapping model employed to recommend new commodities was presented. Attribute comparison was applied to obtain trust value through comparing the attribute value declared of the commodity to the attributes of other commodities whose rating trust values could be computed. Trust transitivity was used to obtain trust value through aggregating the rating trust values of other commodities in the same shop. The evaluation of the credible degree of rates reduced the damage of malicious rates and promoted the accuracy of trust values. Analysis and experimental results showed that the proposed trust bootstrapping model could achieve the forecast target and the proposed method has obvious advantages compared to other methods.关键词：rating;security systems;e-commerce;trust;reputation
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发布时间：2023-11-14 - 摘要：Abstract:By analyzing existing ciphertext-policy attribute-based encryption scheme, ciphertext-policy weighted attribute-based encryption scheme was proposed. To solve the existing scheme without considering the attribute with weight, the concept of weight was adopted into ciphertext-policy attribute-based encryption scheme. Meanwhile, the security of ciphertext-policy weighted attribute-based encryption scheme was proved under the selective-weighted attribute model. Moreover, the ciphertext-policy weighted attribute-based encryption scheme was given which has effective application in secure cloud computing environment. Analysis showed that the present scheme is more appropriate for the cloud computing environment than the existing schemes.关键词：cloud computing;access control;public key cryptography
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发布时间：2023-11-14 - 摘要：Abstract:Attribute-based signcryption provides not only the chance that the participants access the cipher texts by their attributes instead of identities, but also the combined security of confidentiality and unforgeability. An attribute-based signcryption scheme from multi-linear maps was proposed. The circuits presented by Sahai et.al was used as the access structure to support the arbitrary fanout, and the outsourcing computing was employed to reduce the receivers’ computational cost. The security was evaluated in the standard model under the k-decision multi-linear problem assumption. Compared with the existed schemes, the decryptor saved the key communication cost up to 66.7%. Furthermore, the constant cipher texts were kept after being outsourcing computed. The computational cost of the receiver was 8p+(n+3)e.Additionally, this scheme could be verified publicly and gives the foundation of performing secure communication in social networks and others.关键词：public key cryptography;network security;attribute-based signcryption
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发布时间：2023-11-14 - 摘要：Abstract:Broadcast signcryption can make the sender send multi messages to recipients by one operation. In order to efficiently solve the problems of low efficiency, large overhead and privacy security in “one-to-many” communication model, an ID-based broadcast signcryption scheme (IBBSC) with user anonymity was proposed. Using bilinear pairings and the Lagrange interpolating function, the signcryption scheme was constructed. And the security of the algorithms was proven based on decisional bilinear Diffie-Hellman problem and computational Diffie-Hellman problem. The public verifiablity and user anonymity were also achieved in addition to the confidentiality and unforgeability in the IBBSC. Analysis showed that the signcryption algorithm operates only in(t+3)s+p, smaller than the amount of computation of similar schemes, and it significantly improved the efficiency of computations.关键词：broadcast signcryption;Lagrange interpolation;public verifiability;user anonymity
- 3005
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发布时间：2023-11-14 - 摘要：Abstract:Because of the traditional medium-and long-term prediction method used to select parameters without reasonable basis when modeling, and the slow convergence speed,complex structure and parameter optimization process of the models we commonly used, an stochastic medium-and long-term prediction method was put forward based on WA and GRNN.The main idea of this model was as follows:First,the multi-time scale characters of hydrologic time series were analyzed with WA method.Then GRNN was used to predict the deterministic component and periodic component, respectively. Finally the two components were stacked as final prediction results. The proposed method was used to predict the data of annual runoff series for Tuojiang River.The results showed that the model was of higher accuracy and better qualified rate than traditional prediction models which indicated the validity and applicability for analyzing and modeling hydrological series.关键词：GRNN neural network;wavelet analysis;annual runoff;medium-and long-term hydrologic forecasting;hydrologic time series
- 2095
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发布时间：2023-11-14 - 摘要：Abstract:Autogenous deformation of dam concrete still brings influence to crack resistance performance.With test results from full-graded and wet-screened samples,autogenous deformation model of Jinping I arch dam was presented. Dam concrete’s initial deformation is not related with temperature stress and final deformation is from concrete’s drying shrinkage.It showed that autogenous deformation maximum of Jinping I arch dam is to -29.8×10-6,autogenous deformation values from full-graded tests of 120 d age is below those from wet-screened samples.But,in 150 d age,deformation values of full-graded tests are above those from wet-screened samples. Expansion admixture is introduced into concrete on construction period and could prevent shrinkage deformation.关键词：autogenous deformation;wet-screened tests;full-graded tests;Jinping I arch dam
- 2119
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发布时间：2023-11-14 - 摘要：Abstract:In order to treat the problem of low efficiency of the inversion of mechanical parameters of surrounding rock, an asynchronous particle swarm optimization method with high efficiency was proposed to the parameters inversion of surrounding rock, and a mathematical inversion model was established. Based on the file partition, information grouping and sequence encoding, the parametric auto-generation and update of FEM calculation file were realized. Then the realization process of inversion of mechanical parameters and advanced prediction of mechanical response of surrounding rock was given, and automatic system was developed. The example results showed that the proposed method and the developed system are feasible and practical.关键词：underground cavern;inversion of mechanical parameters;advanced prediction;aynchronous particle swarm optimization method;ABAQUS
- 1973
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发布时间：2023-11-14 - 摘要：Abstract:In order to resolve the difficulty of the quantitative simulation and integrated assessment of rural non-point sources pollution(RNPSP) in regions with sparse data,a simple and practical RNPSP assessment method was developed by combining the export coefficient model(ECM) and source strength coefficient method(SSCM).The corresponding coefficients were selected based on the analysis of the literatures and field survey data.This method and the coefficients were applied to the RNPSP assessment for the Laixi River basin(the part within the Lu county,Sichuan,China),a region with sparse data for coefficient calibration,and the assessments of the dominant pollution source type,key pollutants and key pollution sources of the study area,key towns for pollution treatment,and key pollution sources for each town were obtained.Finally,reasonable and practical suggestions were proposed for the water pollution treatment according to the assessment results.The results showed that the proposed method can be applied to the RNPSP assessment for the regions with sparse data.关键词：rural non-point sources pollution assessment;export coefficient model;source strength coefficient method;treatment countermeasures;the Laixi River basin
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发布时间：2023-11-14 - 摘要：Abstract:To explore velocity distribution of turbulent flow in rectangular channel under the influence of sidewall, the comparison and analysis of the main formula of velocity distribution which are applicable to rectangular channel in current were presented and the advantages and disadvantages were listed.The parabolic distribution was selected which reflects vertical velocity distribution near sidewall well.According to the three-dimensional Reynolds equation,a model of mathematical physics on turbulence was created. Cross-sectional velocity distribution formula and average velocity transverse distribution formula under the influence of side-wall were deduced.Ify/h>0.2,the relative error between measured value and calculated value is less than or equal to 3% in channel central region,and the relative error is at about 6% in side-wall region.If y/h<0.2,the maximal error between measured value and calculated value is about 10%.The formula can reflect velocity distribution along the vertical and horizontal well,which has important theoretical significance and practical value.关键词：velocity profile;rectangular channel;turbulent flow;reynolds equation;parabola
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发布时间：2023-11-14 - 摘要：Abstract:Microscopic damage mechanism has an important impact on the macroscopic mechanical properties of concrete materials. Based on the statistical damage theory and the experimental phenomena,a statistical damage constitutive model for concrete under biaxial compression was proposed, in which two microscopic damage modes, rupture and yield,were considered.The whole damage evolution process was driven by the principal compressive strain. The concept of “equivalent transfer tensile damage strain” was introduced, and the compressive damage in press direction was controlled by the lateral tensile damage strain. By this model, the envelope composed of the stress-strain curves under biaxial compressive proportional load path was predicted. Furthermore, the strength envelope was obtained. The damage mechanism of concrete under biaxial compression was discussed from the view points of biaxial strength, deformation properties and the envelope shape. The results showed that it can accurately reflect and predict the constitutive behavior of concrete under biaxial compression, and reveal the microscopic mechanism of damage evolution. The yield damage mode plays a critical role, by which the whole deformation and failure process can be divided into the statistical uniform damage phase and the local failure phase. The two characteristic states，the peak nominal stress state and the critical state when macro-crack appears,were distinguished,and the latter was proposed as the final failure point in the constitutive model.关键词：concrete;biaxial compression;statistical damage;constitutive model;stress-strain curve
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发布时间：2023-11-14 - 摘要：Abstract:CBR value which reflects the capacity of partial soil resisting shear failure is an important testing standard of embankment filling quality. Based on the background of improving project scheme of high limit liquid soil,a series of indoor tests was carried out to study bearing ratio influencing factors of the obvious regional characteristics of high liquid limit soil mixed with soil,and the influence rule of water content, swelling rate,dehydration rate of the high liquid limit soil in different sand content and different wet and dry cycles on CBR value was obtained.The results showed that water is the main reason of expansion shrinkage and differences of CBR value.The action of sand and fracture dominates at the earlier stage and the later stage of dry-wet circulation, respectively.The high liquid limit soil should be filling in the deep 93 area,but after improved by sand,it can fill in the relatively lower 94 area.关键词：high liquid limit soil;sand;CBR;drying and wetting test;stress analysis
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发布时间：2023-11-14 - 摘要：Abstract:For simulating high Reynolds flows around bridge decks effectively, as well as expanding the application of the lattice Boltzmann method (LBM) in bridge wind resistance, dynamic Smagorinsky sub-grid-scale model was embedded into the multiple relaxation times (MRT) formulation of LBM. The subgrid eddy viscosity can be obtained from performing discrete filtering operations at lattice grid and test-filter levels. Grid filter was locally calculated by means of non-equilibrium moments of the MRT-LBM, while test filter was computed by finite difference method at a larger scale. A MRT-LBM-DSM method, which can simulate high Reynolds flows effectively, was constructed through modifying the kinematic viscosity of the MRT-LBM by incorporating subgrid eddy viscosity. As an example, the Sutong bridge was investigated to calculate its static force coefficients and aerodynamic derivatives. The comparison between simulation and experimental results showed that the present method gives much better prediction of turbulent flows, and can be used for simulating high Reynolds flows around bridge decks and calculating aerodynamic parameters.关键词：lattice Boltzmann method;large eddy simulation;test filter;dynamic Smagorinsky model;aerodynamic parameters
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发布时间：2023-11-14 - 摘要：Abstract:An approach to analyze data field was proposed to compute the data field potential in the setting of big data based on the enzymatic numerical P system(ENPS) which is a novel membrane computing device. At first, this approach employed the transition P system to improve the ENPS so as to enhance the controllability of processes. Then, the improved ENPS was taken into account to design a P system for calculating the potential of big data field. The maximum parallelism of the P system resulted in the accomplishment of calculation on the potential of big data field only in three steps. The running time within each step was constant and independent to the data scale. Experimental results on real data field from face images verified the effectiveness of the proposed method.关键词：data field;big data;membrane computing;enzymatic numerical P system
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发布时间：2023-11-14 - 摘要：Abstract:In order to realize the stereo vision navigation of the autonomous robot, the accuracy and rapidity of image matching become the hotspot and difficulty of the research. From the study of the work environment of the mobile robot, the relative position invariance of image matching was put forward, and based on this principle, the matching algorithm based on the nearest neighbor and the second-nearest neighbor SIFT feature point was improved. All features of the pair matching images (the before and after frame images) were sorted by pixel coordinate value of the Yaxis. Then, the SIFT feature points were searched from the local area of corresponding relation. If the ratio of the nearest and second nearest neighbor meets certain threshold T, the point is the pair matching point. Finally, the error matching points were eliminated by the relative position invariance. The improved algorithm avoids searching the nearest neighbor and the second-nearest neighbor SIFT within the global area, so the real-time performance is improved greatly and the error matching points are eliminated mainly. The experiment result showed that the matching speed and accuracy of the present matching algorithm are greatly improved.关键词：image matching;stereo vision;SIFT;relative position invariant
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发布时间：2023-11-14 - 摘要：Abstract:To solve the problem of low precision in traditional RSSI location estimation schemes in WSN，the virtual anchor RSSI（VA-RSSI）localization algorithm with RSSI valid threshold was presented. The proposed algorithm has three improvements，including update of virtual anchor nodes，the conception and formulation of confidence levels of virtual anchor node，and coordinate calculation of blind nodes by using weighted least square estimates. Simulation results demonstrated that the VA-RSSI algorithm reduces the distance estimation error effectively and achieves better precision at the same network environment.关键词：wireless sensor networks;virtual anchor nodes;confidence levels;RSSI valid threshold;weighted least square estimates
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发布时间：2023-11-14 - 摘要：Abstract:In cognitive radio system, it was still a problem for a secondary user that how the delay and the number of spectrum handoff could be reduced so as to realize transmitting information of numerous data by utilizing spectrum aggregation when the primary user returned. A proactive handoff strategy was proposed and applied to the spectrum aggregation to solve this problem. According to the transition probability of the secondary user and the constraint of span, the strategy formulated a new regulation for proactive handoff of the secondary user to ensure smoothing handoff and to avoid the collision. Meanwhile,a backup channel selection method based on handoff probability was advised to cut down spectrum handoff delay and handoff number. Simulation results showed that when the average interval of PUs’ arrivals was higher than 50 slots and average holding time in a sub-channel of the SU was less than 100 slots, the handoff strategy of spectrum aggregation could keep the number of handoff below 5 times and shorten the delay below 30 slots. The strategy not only guaranteed the real-time of handoff but also reduced the cost of handoff as much as possible to promote the efficiency of system.关键词：spectrum aggregation;spectrum handoff;delay of handoff;number of handoff
- 2078
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发布时间：2023-11-14 - 摘要：Abstract:A novel de-coherence algorithm,called cross-correlation vector reconstruction by changing the reference element(CVRCRE) algorithm, was proposed to estimate the DOA of coherent signals. Using cross-correlation information of received data between the whole array and the reference element, an equivalent covariance matrix which had excellent de-coherence performance was reconstruted. Combined with the subspace algorithms, such as MUSIC and ESPRIT, the DOA of coherent signals could be estimated. The proposed algorithm avoides the loss of array physical aperture. Computer simulation confirmed that the CVRCRE algorithm achieves better performance than Toeplitz algorithm and FBSS algorithm under scenarios of low SNR and deficient snapshots.关键词：array antenna;direction of arrival;vector reconstruction;coherent
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发布时间：2023-11-14 - 摘要：Abstract:In order to study the voltage interaction and the multi-infeed interaction factor of the AC/DC parallel power system and multi-infeed HVDC, the solving method for the voltage interaction and multi-infeed interaction factor was proposed by analyzing the impedance characteristic of asynchronous motor, characteristic equations of converter stations and the increment of node power on the basis of the incremental form of power flow equation. It was pointed out that the equivalent impedance of asynchronous motor is a function of voltage, the voltage interaction relationship among nodes is related to the structure and operating state of the whole system and control mode of the DC system, and the ratio between increments of node voltage is a constant approximately. Finally, the effectiveness and accuracy of the voltage interaction formula were verified by a specific case.关键词：voltage of commutation bus;interaction;multi-infeed interaction factor;control mode;dynamic load;AC/DC system
- 1837
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发布时间：2023-11-14 - 摘要：Abstract:The space-time distribution features of frequency responses were proposed to analyze varieties between the disturbing source generator and generators in the same/different areas in power system forced oscillations．The oscillating components of various frequency increments had different initial phases which resulted in different time of the first oscillating extreme value for the frequency increments in forced oscillation．The frequency increments of the disturbing source generator always achieved its first oscillating extreme value earlier than which of other generators．The delays of other generators in the same area with the disturbing source generator were determined by the value and initial phase of intra-area oscillating frequency, meanwhile, the delays of other generators in another area with the disturbing source generator were determined by the value and initial phase of inter-area oscillating frequency．Both the theoretical and practical case study showed that utilizing space-time distribution features of variational frequency responses could analyze forced oscillation effectively and locate disturbing source generator.关键词：forced oscillation;space-time variation;the first extreme value;disturbing source location
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发布时间：2023-11-14 - 摘要：Abstract:In oder to effectively control the output power in three-phase wireless power transfer system, taking the voltage-fed three-phase series resonance inverter as an example, based on traditional 180° control mode, a new control mode named switch on-off mixed symmetric control mode was proposed by adding a short cutoff pulse in the 180° conduction process of the switch, and adding a short setup pulse in the 180° block process symmetrically. The equivalent output line voltage and phase voltage of the resonance compensating network would be varied, which can effectively control the output power of the inverter system. By mathematical modeling, the functional relationship between the power transmission capacity and the pulse electrical angle was derived, which provids a theoretical basis for system design and analysis. From the simulation and the experimental results, it could be concluded that the output power of system could be controlled by this new control scheme, meanwhile, the theoretical analysis was verified.关键词：three-phase inverter;series resonance;mixed symmetric control;wireless power transfer
- 2051
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发布时间：2023-11-14 - 摘要：Abstract:The dynamic fracture toughness of Magnesium alloy is the basic data for the design of the anti-impact magnesium alloy component and safety assessment of magnesium alloy structure under dynamic load.The combining method of experimental and numerical was improved to obtain the dynamic fracture toughness of magnesium alloy AZ91.The dynamic load for the three point bending specimen was supplied by the Hopkinson pressure bar,and the dispersion and inertia effect were considered and corrected by numerical method, simultaneously,based on the FFT and the VC++ object-oriented programming method.Then the response of dynamic stress intensity factor vs. time was calculated with visual crack close technique method based FEM.Finally,the crack initiation time was computed from the strain gauge message,and the corresponding value on the response of dynamic stress intensity factor vs. time was obtained as the dynamic fracture toughness.Considering that,the actual three-point bending condition,which is guaranteed by the monitoring message during the process,was acquired through the adjusting of specimen span.The results showed that the dynamic fracture toughness of magnesium alloy AZ91 is (6.7±1.8) MPa·m1/2.In addition,the method mentioned extends the application of Hopkinson pressure bar for measurement of dynamic fracture toughness.关键词：magnesium alloy;Hopkinson pressure bar;dynamic fracture toughness
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发布时间：2023-11-14 - 摘要：Abstract:The MW wind turbine casting was prepared by metal mold gravity casting process. In order to improve the mechanical properties of the MW wind turbine via modifying the casting technology, the impact toughness of the MW wind turbine was studied under different sampling directions, impacting ways, and shocking temperatures. The results showed that the impact toughness of the MW wind turbine has significant differences under different sampling directions and impacting conditions. Moreover, it is worth mentioning that the impact toughness taken along the direction of metallic fiber is distinctly higher than the ones of other directions.关键词：wind turbine;impact toughness;sampling directions;casting instead of forging
- 1968
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发布时间：2023-11-14 - 摘要：Abstract:A method for linear distance measurement based on reference plane was proposed according to the vanishing point principle.The spatial relationship between camera and reference plane was established with the known dimension rectangular calibration objects on the premise of the known camera internal parameters.Keeping the camera position and focal length unchanged and shooting a digital image,the linear distance between two feature points in reference plane was calculated.This method has the characteristics of calibration and high precision.关键词：digital image;reference plane;calibration objects;vanishing point
- 2006
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发布时间：2023-11-14 - 摘要：Abstract:The traditional methods have used graphics to treat the problem of the overlap or outside testing and layout estimating of 2-D irregular nesting.In the present work,new methods based on image and color statistics were proposed,which included a method based on area and histogram,and a method based on edge.Time performance test and complexity analysis were carried for all these methods.The results showed that in small image the performance of the method based area is barely OK,but in large image the consuming time is long,being square level of the image dimension.The method based on edge has better performance,especially in large image,which time being linear level of image dimension.关键词：nesting;irregular polygons;estimate;overlap testing;image
- 1889
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发布时间：2023-11-14 - 摘要：Abstract:The onboard hydraulic oil source system has some fault-free behaviors with normal distributed periods and some faulty ones with exponentially distributed periods. The model of the onboard hydraulic oil source system was built by normal-stochastic PNs which combined firing periods with normal and exponential distribution. A method was proposed for the the firing periods parameters identification, which was the mean value mand the periods standard deviation σfor normal distribution or the exponential distribution mean value μ. The simulation results showed that the computing operating periods parameters were consistent with the real operating periods parameters.关键词：stochastic Petri Nets;non-Markovian;modeling;parameter identification
- 1887
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发布时间：2023-11-14 - 摘要：Abstract:Product development activity always involves the innovative thinking of various participants. The cognitive thinking process is complicated. Based on the characteristics of cognitive thinking,a collaborative innovation process of cognitive thinking was summarized,and an innovative strategy of multi-method and design process was proposed. Combined with the design process, the aspects of collaborative innovation personnel, process operation and decision making were explored. The design activities and thinking operations of various participants were organized and standardized to maximize the collective creativity and promote the innovation activities. Finally, an example of nailing machine was taken to show the collaborative process and demonstrate the effectiveness of its application.关键词：multi-participant;collaborative innovative thinking;cognitive thinking process;collective creativity cognition
- 2018
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发布时间：2023-11-14 - 摘要：Abstract:In order to solve the problem that the API-579 can only assess the residual strength and safety of the metal pressure pipeline under one of the given eight modes, the concept of area occupation ratio of pitting was proposed. The corresponding relationship between area occupation ratio of pitting and remaining strength factor and ratio of the remaining wall thickness to the future wall thickness was built respectively. Furthermore, a non-discrete characterization model of residual strength was proposed. The model could be used not only to assess the residual strength but also the safety of the pipeline with pitting corrosion under the eight modes given in API-579 standard. The model made it possible to predict the dynamic remaining life of the pipeline with pitting corrosion.关键词：metal pressure pipeline;non-discrete characterization model;pitting;remaining life
- 1903
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- 8
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发布时间：2023-11-14 - 摘要：Abstract:In order to increase the removal efficiency of fluoride ion aqueous solution, using humic acid(HA) as raw materials,a composite gel of metal ion and humic acid (abbreviated as SPMA) was synthesized by gel polymerization method.The structures and appearances of adsorption materials were analyzed by SEM,XRD,IR and N2 adsorption-desorption isotherms technique as well.The batch adsorption experiments were carried out.The results indicated that the adsorption isotherm behavior of SPMA followed the Langmuir equations,and the maximum adsorption capacity was 147.28 mg/g.The adsorption kinetics followed the pseudo-second-order rate model. The adsorption of F- for SPMA was due to the liquid film diffusion and the intra-particle diffusion. Maximum fluoride adsorption of SPMA from the contaminated water was reaches at pH 5~9,and the SO42-,NO3-and Cl- has no effect on removal efficiency of F-,SPMA removed F- at the removal efficiency of 80% in dilute solution even when the HCO3- and PO43- at the same concentration.Therefore,the SPMA could be used for the selective adsorption for F- in dilute solutions.关键词：humic acid;metal ion;gel;adsorption;fluoride
- 1858
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发布时间：2023-11-14 - 摘要：Abstract:The stress corrosion cracking (SCC) behavior and its mechanism of N80 steel under different H2S partial pressure in the environment of CO2 were studied using electrochemical technology and U-bent specimen immersing test. The results showed that the CO2-H2S environment generates the SCC of N80 oil casing steel.The corrosion current and susceptibility of N80 oil casing steel increases,then decreases with the increase of H2S partial pressure.When the H2S partial pressure exceeds 0.2 MPa,the N80 oil casing steel exhibits a high susceptibility to SCCThe typical intergranular fracture morphologies are observed in the first,but then stress corrosion cracking becomes transgranular and intergranular fracture morphologies.The SCC mechanism is mixed-controlled by both anodic dissolution (AD) and hydrogen-induced (HE).关键词：N80 steel;H;S;CO;2;electrochemical;stress corrosion cracking
- 2514
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发布时间：2023-11-14
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