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Objective To summarize the performance and implementation status of various randomization methods, and to provide clinical researchers with a guide for choosing an appropriate randomization method and executing it in a standardized manner. Methods The review elucidated the conceptual and implementation integrity of randomization, and illuminated the developmental history and application of major randomization methods, as well as their performance in the two competitive dimensions of group allocation randomness and group sample balance. Results Restricted randomization was frequently used to maintain an appropriate treatment balance in practice. Block randomization was the most widely used, but its allocation sequence lacked sufficient randomness and could be predicted, elevating the risk of selection bias, especially in open-label trials. Methods offering a superior trade-off between randomness and balance included MTI restricted randomization methods like the big stick design and maximal procedure, as well as combinations of multiple randomization methods such as the block urn design and sandwich mixed randomization. Many clinical researchers still had misconceptions about the randomization concept itself and often overlooked its critical methodological rigor and standardized implementation. Conclusion Researchers should meticulously choose a suitable randomization method and report implementation details in a standardized manner, allowing peer researchers to evaluate the internal validity and evidence strength of the study. Due to its high predictability, the widely used block randomization method should be substituted by alternative methods with better performance. Future randomization procedures can be explored and developed based on the MTI restrictive methods and the combinations of existing methods. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Signal Processing is the property of Journal of Signal Processing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to achieve better test performance, researches on the randomness test strategies based on deep learning were conducted, including the batch average strategy proposed by EUROCRYPT 2021 and the selection strategy for data unit size.By introducing the randomness statistical test model based on deep learning methods, the statistical distribution and test power expression of two test strategies were theoretically derived, and it was pointed out that: (i) the batch average strategy could amplify the prediction accuracy of the model, but it was prone to an increase in the probability of the second type of error in statistics, instead reducing the statistical test power; (ii) the smaller data units of the deep model generally obtained the more powerful statistical tests.Based on the above understanding, a new bit-level deep learning model was proposed for randomness statistical tests, which gained the advantage of prediction with 80 times fewer parameters and 50% samples, compared with the previous work on linear congruent generator (LCG) algorithm, and achieved significant prediction advantages with 10～20 times fewer parameters by extending the model to apply to 5～7 rounds of Speck, compared with the model proposed by Gohr.

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The differential frequency hopping (DFH) overcomes the limitation of frequency hopping and improves the ability to resist tracking interference.The G function determines the DFH sequence and directly affects the performance of DFH communication systems.However,with the complication of wireless communication system such as large capacity DFH network,which poses huge challenges to the use of the number theory based and chaos theory assisted sequence.As a result,in order to improve the security of the system,the novel G function construction was proposed with the aid of hybrid encryption algorithm and the security of hybrid algorithm was analyzed.Moreover,the equivalence principle of G function algorithm and the encryption algorithm was proved.The simulation results show that the DFH sequence generated by the new G function has excellent performance and the performance of the DFH systems is improved greatly.

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The collapsed and landslide deposits on the bank of the gully in mountain areas are significant material sources for the formation and supply of debris flow. After the earthquake, this replenishment role has been increasingly crucial over time. For studying the lateral erosion failure process and law of these accumulations under the action of flow in debris flow gully, the lateral erosion failure process of the deposits with different bed slope, upstream flow, and fine particle content was studied by laboratory flume experiment. This paper mainly analyzes and summarizes the phenomenon and randomness law in the process of lateral erosion failure of side-shore deposits in the experiments. The results show that the erosion process of the deposits mainly includes the erosion stage of slope toe and the instability stage. The slope toe erosion stage is continuous and stable, and the main dynamic condition is hydraulic erosion; the prime driving force in the instability stage is gravity erosion, and the soil failure in this stage shows paroxysmal and fluctuation. The interval time and the scale of soil failure can be regarded as random sequences, and the interval time fit Poisson distribution, and its magnitude fit Pareto distribution. The influence of different experimental conditions on soil failure activities is mainly reflected in the instability frequency. The frequency of soil failure increases with the increase of the slope gradient and flow. Under the small bed slope gradient ( 3 °), the frequency of soil failure increases with the increase of fine particle content. With the increase of bed slope gradient ( 7°), the frequency of soil failure increases first and then decreases with the increase of fine particle content. When the bed surface is in a steeper slope condition ( 11 °), the frequency of soil failure decreases with the increase of fine particle content. The research results can provide a reference for the analysis of the formation mechanism of debris flow. [ABSTRACT FROM AUTHOR]

Software-defined network is based on flexible and open standards,which manages network functions and services by the control layer.And it has the unique advantages of control-separation and centralized control.The moving target defense technology is dedicated to build an ever-changing environment to increase the uncertainty of the network system,which requires a flexible and customizable,centralized and controllable network architecture to implement it.Therefore,the combination of moving target defense and software-defined network have become a more valuable research hotspot.Firstly,the basic concepts of software-defined network and moving target defense were introduced,the security threats of software-defined network was summarized,and the realization model of moving target defense for SDN network was described.Secondly,the technical methods for moving target defense were summarized respectively form the data layer,control layer and application layer of the SDN.Finally,summing up the challenges of existing SDN dynamic defense,and looking forward to the development direction of moving target defense technologies for the SDN.

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to the characteristics of uncertainty, including fuzziness and randomness in natural disaster risk assessment, uncertainty analysis was synthetically considered through the new method of natural disaster risk assessment based on cloud model and risk matrix. The numerical characteristics of cloud of each factor on different risk levels was generated based on the grading standard of evaluation indexes, considering positive Gauss cloud algorithm and composite risk matrices between each two evaluation indexes and the comprehensive risk level in certain region was finally specified. By comparing the assessment results from the proposed cloud model with those of a practical example and other methods, it can be concluded that the proposed cloud model is reliable and simple and its feasibility and effectiveness are verified. It may provide a new research method for uncertainty analysis of other similar issues. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the randomness problem of rock dynamic response parameters, the experimental system of dynamic response characteristics of sandstone under random shock perturbation is adopted, and the dimensionless quantity-relative mean value deviation factor is introduced to quantitatively study the dynamic response frequency of fine sandstone sample under random disturbance force. The results show that different dynamic response parameters have different discrete degree to sandstone sample under random excitation; the randomness of acceleration amplitude spectrum parameters is stronger than that of the power spectral density parameters; the average of relative mean value deviation factor of power transmission coefficient is less than that of corresponding excitation, and the power transmission coefficient of acceleration amplitude spectrum parameters is the opposite. The randomness of the rock dynamic response parameters randomness is inevitable, and quantitative analysis of discrete degree of different dynamics parameters is helpful to improve the prediction reliability of the dynamic disaster in underground mining engineering. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Image & Graphics is the property of Editorial Office of Journal of Image & Graphics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The latin hypercube sampling technique was used to obtain sample points of structure parameters for angular contact ball bearings. A combination method of the Powell algorithm and Newton-Raphson method was proposed for solving nonlinear equations and then the as-obtained the bearings stiffness were applied on fitting response surface functions based on the Kriging model. The influence of the mean and variation of structure parameters for angular contact ball bearings on its stiffness sensitivity was simulated using the Monte Carlo method. The results show that the mean and variation of structure parameters for angular contact ball bearings have an adverse effect on the sensitivity of the axial and radial stiffness. Bearings stiffness is most sensitive to the variation of ball diameters， then curvature radius of the inner and outer raceway groove takes the second place， and the outer raceway diameter is the least. This research may bring forward the theoretical basis for selecting the design parameters and machining accuracy of bearings as well as separation of parts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The nonlinear behavior of concrete structure under dynamic loadings is strongly influenced by loading rates. To investigate the strain rate effect of concrete and its corresponding influence on the stochastic property of concrete, a total of 418 prismatic specimens with strength grade ranges from C30 to C60 subjected to uniaxial compression were tested, involving eight different strain rates between 10-5/s and 10-1/s. The experiments were conducted on the MTS815 testing system and about 16 specimens designed and casted on the same condition were tested for every set of case. The mean and standard variation values of the uniaxial compressive stress-strain curves, as well as the statistical characteristic values of compressive stress and peak strain of concrete with different strength under different strain rates, were obtained through the experiments. Experiment results indicate that the strain rate has a significant influence on the stress-strain mean value curves while other properties rarely change with strain rate. [ABSTRACT FROM AUTHOR]

The probability density evolution method and the advanced nonlinear analysis technique adopting damage constitutive law of concrete are incorporated，whereby the stochastic response analysis of structures based on traditional simplified component-structure two-level models is improved to the level of refined analysis involving stochastic constitutive law of material-structure coupling. Probability density evolution analysis of stochastic nonlinear response of multi-story concrete frame structures with random structural parameters is then implemented. Further, the randomness involved in concrete and steel materials and damping parameter is taken into account，and the properties of stochastic evolution of major responses are examined，showing that due to the effects of stochastic damage of concrete. Compared to the responses of linear structures，the variability of the axial force of column and the inter-story shear force changes a lot, whereas the probability density evolution surfaces of inter-story shear and inter-story drift tends to be more irregular. [ABSTRACT FROM AUTHOR]

To avoid the disadvantages of traditional sequence ciphers algorithm with highly coincident code rate and easily falling into local optimal,this paper proposed a sequence encryption generating method based on multi-objective differential evolutionary algorithm (DEMOSEP). The presented algorithm used three indicators as the optimized objective functions,namely frequency-test, sequence-test and runs-test to evaluate the randomness of sequence. In addition, it used the efficient operators of differential evolution, and combined the fast non-dominated sorting with the crowded distance selection mechanism to evolve sequence ciphers which could meet these three indicators. The experimental results show that the sequence encryption generating method has high randomness and security,and also has some practicality. [ABSTRACT FROM AUTHOR]

Starting from the material randomness and nonlinear performance of concrete, the stochastic damage mechanics of concrete was systematically investigated. It is found that the mechanical behavior of concrete relies on the coupling between randomness and nonlinearity. And the fluctuation of randomness in different scales should be carefully considered to handle the failure of structures. Moreover, the randomness of concrete in the material level changes the nonlinear behaviors of structures subjected to disastrous excitations. The stochastic damage mechanics of concrete lays a solid foundation for the reliability based design and control of concrete structures. [ABSTRACT FROM AUTHOR]

In order to analyze and evaluate the risk of network security more reasonably, a cloudmodel based method for network security analysis was proposed. The main ideas, key technical and implementation steps of the method were given. The standard clouds were generated using improved backward cloud algorithm with unknown certainty. The improved algorithm with smaller deviation was also proved. Finally, Kddcup99data set was used to simulate. The experimental results show that the proposed method retains the uncertainty of risk analysis. It provides a strong reference to adopt appropriate preventive measures. [ABSTRACT FROM AUTHOR]